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11,036,687 | ACCEPTED | Inductively powered apparatus | An inductive power supply system for providing power to one or more inductively powered devices. The system includes a mechanism for varying the physical distance or the respective orientation between the primary coil and secondary coil to control the amount of power supplied to the inductively powered device. In another aspect, the present invention is directed to an inductive power supply system having a primary coil and a receptacle disposed within the magnetic field generated by the primary coil. One or more inductively powered devices are placed randomly within the receptacle to receive power inductively from the primary coil. The power supply circuit includes circuitry for adjusting the power supplied to the primary coil to optimize operation based on the position and cumulative characteristics of the inductively powered device(s) disposed within the receptacle. | 1-82. (canceled) 83. An inductive adapter for use in a conventional lamp socket comprising: an adapter base including: a screw base to be fitted within a conventional threaded lamp socket, a power supply circuit electrically connected to said screw based to receive power through the conventional threaded lamp socket, a primary electrically connected to and receiving power from said power supply circuit, and a lamp assembly receptacle; and a lamp assembly fitted within said lamp assembly receptacle, said lamp assembly having a secondary electrically connected to a light source, said secondary receiving power inductive from said primary to provide power to said light source. 84. The inductive adapter of claim 83 further comprising a mechanical dimmer for varying a position of said lamp assembly within said receptacle. 85. The inductive adapter of claim 84 wherein said mechanical dimmer include a cam disposed on at least one of said adapter and said lamp assembly. 86. The inductive adapter of claim 84 wherein said mechanical dimmer include a thread disposed on at least one of said adapter and said lamp assembly. 87. The inductive adapter of claim 84 wherein said lamp assembly receptacle defines a void, said lamp assembly including a secondary housing fitted closely within said void. 88. The inductive adapter of claim 87 wherein at least one of said lamp assembly receptacle and said secondary housing includes a resilient member engaging the other of said lamp assembly receptacle and said secondary housing. 89-96. (canceled) | The present invention is a continuation-in-part of U.S. application Ser. No. 10/133,860 entitled “Inductively Powered Lamp Assembly,” which was filed on Apr. 26, 2002 and is a continuation-in-part of U.S. Application Serial No. 90/592,194 entitled “Fluid Treatment System,” which was filed on Jun. 12, 2000. The present application is also a continuation-in-part of U.S. application Ser. No. 10/246,155 entitled “Inductively Coupled Ballast Circuit,” which was filed on Sep. 18, 2002 and is a continuation-in-part of U.S. patent application Ser. No. 10/175,095 entitled “Fluid Treatment System,” which was filed on Jun. 18, 2002, which is a continuation-in-part of U.S. patent application Ser. No. 09/592,194 entitled “Fluid Treatment System,” which was filed on Jun. 12, 2000. U.S. patent application Serial No. 90/592,194 claims the benefit under 35 U.S.C. §119(e) of U.S. provisional patent application Ser. No. 60/140,159 entitled “Water Treatment System with an Inductively Coupled Ballast,” which was filed on Jun. 21, 1999, and U.S. provisional patent application Ser. No. 60/140,090 entitled “Point-of-Use Water Treatment System,” which was filed on Jun. 21, 1999. The present application is a continuation-in-part of U.S. application Ser. No. 29/165,043 entitled “Bulb,” which was filed on Aug. 2, 2002; U.S. application Ser. No. 29/165,008 entitled “Bowl Lamp,” which was filed on Aug. 2, 2002; U.S. application Ser. No. 29/165,012 entitled “Bulb,” which was filed on Aug. 2, 2002; U.S. application Ser. No. 29/165,005 entitled “Lamp,” which was filed on Aug. 2, 2002; U.S. application Ser. No. 29/165,009 entitled “Bulb,” which was filed on Aug. 2, 2002; and U.S. application Ser. No. 29/165,011 entitled “Chime,” which was filed on Aug. 2, 2002. BACKGROUND OF THE INVENTION The present invention relates to wireless power supplies, and more particularly to inductively powered devices. The principles of inductive power transfer have been known for many years. As a result of mutual inductance, power is wirelessly transferred from a primary coil (or simply “primary”) in a power supply circuit to a secondary coil (or simply “secondary”) in a secondary circuit. The secondary circuit is electrically coupled with a device, such as a lamp, a motor, a battery charger or any other device powered by electricity. The wireless connection provides a number of advantages over conventional hardwired connections. A wireless connection can reduce the chance of shock and can provide a relatively high level of electrical isolation between the power supply circuit and the secondary circuit. Inductive couplings can also make it easier for a consumer to replace limited-life components. For example, in the context of lighting devices, an inductively powered lamp assembly can be easily replaced without the need to make direct electrical connections. This not only makes the process easier to perform, but also limits the risk of exposure to electric shock. The use of inductive power transfer has, however, for the most part been limited to niche applications, such as for connections in wet environments. The limited use of inductive power transfer has been largely the result of power transfer efficiency concerns. To improve the efficiency of the inductive coupling, it is conventional to carefully design the configuration and layout of the primary and secondary coils. The primary and the secondary are conventionally disposed within closely mating components with minimal gap between the primary and the secondary. For example, the primary is often disposed within a base defining a central opening and the secondary is often disposed within a cylindrical component that fits closely within the central opening of the base. This and other conventional constructions are design to provide close coaxial and radial alignment between the primary coil and the secondary coil. Several specific examples of patents that reflect the conventional approach of providing a fixed, predetermined physical relationship between the primary and secondary coils include: U.S. Pat. No. 5,264,997 to Hutchisson et al, which discloses an inductive lamp with coaxial and closely interfitting primary and secondary coils; U.S. Pat. No. 5,536,979 to McEachern et al, which discloses an inductive charging device in which the device to be charged is fitted closely within a cradle to position the coils in a fixed, predetermined relationship; U.S. Pat. No. 5,949,155 to Tamura et al, which discloses a shaver with adjacent inductive coils set in a fixed relationship; U.S. Pat. No. 5,952,814 to Van Lerberghe, which discloses an inductive charger for a telephone wherein the physical relationship between the primary and secondary coils is fixed; and U.S. Pat. No. 6,028,413 to Brockman, which discloses a charging device having a mechanical guide for ensuring precise, predetermined alignment between the inductive coils. The conventional practice of providing precise alignment between the primary and secondary coil has placed significant limitation on the overall design and adaptability of inductively powered devices. Further, in conventional inductive systems, the power supply circuit, which drives the primary coil, and the secondary circuit, which inductively receives power from the primary, are designed and carefully tuned to match with one another to maximize the efficiency of the inductive coupling. This too has placed significant limitations on the overall design and adaptability of inductively powered devices. SUMMARY OF THE INVENTION The aforementioned problems are overcome by the present invention wherein an inductively powered device is provided with a mechanism for varying the relative position between the primary and the secondary to control the amount of power supplied to the load. In one embodiment, the present invention is incorporated into a dimmable lamp assembly in which a primary is mounted to the lamp base and the secondary is mounted to the lamp assembly. The brightness of the lamp is controlled by adjusting the distance between the lamp assembly and the lamp base. In a second embodiment, the present invention is incorporated into a dimmable lamp assembly in which the lamp brightness is controlled by varying the relative angular orientation of the primary and the secondary. In this embodiment, the primary is generally ring-shaped and the secondary is pivotally mounted within the ring. The lamp assembly includes a mechanical dimmer that rotates either the primary or the secondary so that their relative angular orientation varies. The variation in relative orientation varies the amount of power transferred to the secondary, thereby varying the brightness of the lamp. In another embodiment, the present invention is incorporated into a wind chime having one or more lamps that vary in brightness based on the movement of the chimes. In this embodiment, a plurality of chime assemblies is suspended within a primary coil, with each chime assembly being individually movable. Each chime assembly includes a secondary disposed at its upper end within the magnetic field of the primary. As the wind blows, the chime assemblies swing with respect to the primary, thereby varying the locations and orientation of the secondary coils within the magnetic field of the primary. This causes the brightness of the wind chimes to vary in respond to the wind. In yet another embodiment, the present invention provides an infinitely adjustable power supply for use with electrically powered devices where it is desirable to adjust the magnitude of power supplied to the device. The power supply includes an inductive coupling disposed between the power supply and the load. The inductive coupling includes a primary and a secondary. The infinitely adjustable power supply also includes an adjustment mechanism for selectively varying the relative position between the primary and the secondary, such as distance or angular orientation. The adjustment mechanism permits adjustment of the coupling coefficient and consequently the magnitude of power induced in the secondary and supplied to the load. In a second aspect, the present invention is directed to an inductive power supply station that is capable of providing power to a plurality of inductive powered devices placed at random location and at random orientations with respect to the primary. The inductive power supply station generally includes a single primary arranged about a receptacle that is capable of receiving randomly placed inductively powered devices. The power supply circuit includes circuitry for adjusting the power supplied to the primary as a function of the inductively powered devices present in the receptacle. In one embodiment, the receptacle is a dish, bowl or similar structure in which one or more lamp assemblies can be placed to provide light. Each lamp assembly includes a secondary that inductively receives power from the primary. The brightness of the light can be controlled by varying the number of lamp assemblies placed in the receptacle and by moving the lamp assemblies within the receptacle. In a third aspect, the present invention provides a secondary with a plurality of coils that are arranged at different orientations. The multiple coils permit the secondary to efficiently receive power when disposed at different orientations with respect to the primary. In one embodiment, a secondary with multiple coils is incorporated into an inductively powered lamp. The lamp assembly can receive maximum induced power when placed at different orientations within the magnetic field of the primary. In another embodiment, the lamp assembly includes a plurality of coils, each being electrically connected to a different light sources, for example, light sources of different colors. By adjusting the orientation of the lamp assembly, the color of emitted light can be varied by altering the respective brightness of the separate light sources. These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a desk lamp in accordance with an embodiment of the present invention. FIG. 2 is a side elevational of the desk lamp of FIG. 1. FIG. 3 is a partially sectional side elevational view of a portion of the desk lamp of FIG. 1. FIG. 4 is an exploded view of a lamp assembly in accordance with one embodiment of the present invention. FIG. 5 is a schematic of a secondary circuit. FIG. 6 is a perspective view of a rack-and-worm mechanical dimmer. FIG. 7 is a perspective view of the base of a desk lamp showing a dial. FIG. 8 is a perspective view of the base of a desk lamp showing a slider. FIG. 9 is a perspective view of the base of a desk lamp showing a rotating top. FIG. 10 is a perspective view of an alternative mechanical dimmer. FIG. 11a is a side elevational view of an alternative desk lamp. FIG. 11b is an enlarged side elevational view of a portion of the alternative desk lamp of FIG. 11a. FIG. 12 is an enlarged perspective view of a portion of the alternative desk lamp of FIG. 11a showing the mechanical dimmer. FIG. 13 is a side elevational view of a second alternative desk lamp. FIG. 14 is an enlarged side elevational view of a portion of the second alternative desk lamp of FIG. 13. FIG. 15 is a sectional view of a portion of the second alternative desk lamp of FIG. 13 showing the binding tab in the locked position. FIG. 16 is a sectional view of a portion of the second alternative desk lamp of FIG. 13 showing the binding tab in the open position. FIG. 17 is a perspective view of a third alternative desk lamp. FIG. 18 is a perspective view of the mechanical dimmer of the third alternative desk lamp of FIG. 17. FIG. 19 is a sectional view of a portion of the mechanical dimmer of the third embodiment. FIG. 20 is a perspective view of a fourth alternative desk lamp. FIG. 21 is a partially exploded perspective view of the third alternative desk lamp with portions removed to show the arm. FIG. 22 is a partially exploded perspective view of the third alternative desk lamp with portions removed to show the primary housing. FIG. 23 is a partially sectional side elevational view of a variable speed fan incorporating an infinitely adjustable power supply in accordance with an embodiment of the present invention. FIG. 24 is a perspective view of a fifth alternative desk lamp. FIG. 25 is a partially exploded perspective view of the fifth alternative desk lamp of FIG. 24. FIG. 26 is a partially exploded side elevational view of replacement lamp base in accordance with an embodiment of the present invention. FIG. 27 is a partially exploded side elevational view of an alternative replacement lamp base. FIG. 28 is a perspective view of a portion of the alternative replacement lamp base of FIG. 27. FIG. 29 is a perspective view of a wind chime in accordance with an embodiment of the present invention. FIG. 30 is a partially exploded perspective view of a portion of the wind chime. FIG. 31 is a partially exploded perspective view of a chime assembly. FIG. 32 is a perspective view of a power supply station in accordance with an embodiment of the present invention. FIG. 33 is a partially exploded perspective view of the primary assembly of the power supply station. FIG. 34 is a partially exploded perspective view of the base of the power supply station. FIG. 35 is a partially exploded perspective view of a lamp assembly in accordance with an embodiment of the present invention. FIG. 36 is a perspective view of a secondary having multiple coils in accordance with an embodiment of the present invention. FIG. 37 is a perspective view of an assembly having multiple secondaries in accordance with an embodiment of the present invention. FIG. 38a is a schematic diagram of a secondary circuit for use with a secondary having multiple coils. FIG. 38b is a schematic diagram of an alternative secondary circuit for use with a secondary having multiple coils. FIG. 38c is a schematic diagram of a second alternative secondary circuit for use with a secondary having multiple coils. FIG. 39a is a schematic diagram of a circuit for use with an assembly having multiple secondaries. FIG. 39b is a schematic diagram of an alternative circuit for use with an assembly having multiple secondaries. FIG. 39c is a schematic diagram of a second alternative circuit for use with an assembly having multiple secondaries. FIG. 39d is a schematic diagram of a third alternative circuit for use with an assembly having multiple secondaries. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is directed to improvements in inductively powered devices. In a first aspect, the present invention provides a inductive coupling in which the relative position between the primary coil (“primary”) and the secondary coil (“secondary”) is selectively varied to permit control over the amount of power transferred to the secondary and consequently to the inductively powered device. This aspect of the invention is described in connection with various lamp configurations, for example, to permit control over the brightness of the light source. This aspect of the invention is also described in connection with other electrically powered devices where control over the amount of power supplied to the inductively powered device is desired. In a second aspect, the present invention is directed to an inductive power supply station. In this aspect, the present invention provides a receptacle for receiving one or more inductively powered devices at random locations and at random orientations. In one embodiment of this aspect, the secondary includes multiple coils arranged at different orientations so that power can be more efficiently induced in the secondary without precise alignment between the primary and secondary. In one embodiment, the secondary includes three coils oriented along the x, y and z axis of a Cartesian coordinate system so that power can be induced in the secondary regardless of the angular orientation of the secondary with respect to the primary. An inductively powered desk lamp 10 in accordance with an embodiment of the present invention is shown in FIG. 1. The lamp 10 generally includes a base 12, a lamp assembly 14 and a mechanical dimmer 16 (See FIG. 3). The base 12 includes a ballast and power supply circuit 18 that drives a primary 20. The lamp assembly 14 includes a secondary circuit 22 having a secondary 24 that is inductively powered by the primary 20 and that applies power to the light source 26. The mechanical dimmer 16 includes a movable arm 28 that is movably attached to the lamp base 12. The primary 20 is mounted to the arm 28 so that movement of the arm 28 results in movement of the primary 20. The lamp assembly 14 is suspended from the lamp base 12 with the secondary 24 positioned within the electromagnetic field created by the primary 20. The arm 28 is mechanically movable to vary the position of the primary 20 with respect to the lamp assembly 14 (and consequently the secondary 24), thereby varying the coupling coefficient between the primary 20 and secondary 24. Changes in the coupling coefficient result in variation in the power transferred to the lamp assembly 14 and ultimately in the brightness of the light source 26. This aspect of the present invention is described in connection with a dimmable lamp 10. The present invention is, however, well-suited for use in virtually any application where variation in the amount of power transferred to the secondary circuit 20 is desired. For example, as described in more detail below, the present invention may be used to provide infinitely adjustable control over the amount of power supplied to a device up to the capacity of the power supply circuit. As noted above, the desk lamp 10 of the illustrated embodiment generally includes a base 12, a lamp assembly 14 and a mechanical dimmer 16. The lamp base 12 generally includes a pedestal 30, a shaft 32 and a primary housing 34. The pedestal 20 of the illustrated embodiment is generally disc-shaped having a diameter of sufficient size to provide a stable support for the shaft 32 and lamp assembly 14, an internal void 31 adapted to house the power supply circuit 18 and portions of the mechanical dimmer 16. The shaft 32 extends upwardly from the pedestal to receive the lamp assembly 14. In the illustrated embodiment, the shaft 32 is somewhat “?”-shaped, providing an aesthetically pleasing visual appearance. The shaft 32 terminates at its upper end in a hook 36 or other connection element configured to receive the ring 38 of the lamp assembly 14. The primary housing 34 is generally ring-shaped and is hollow to provide a shell or housing for the primary 20. The primary housing 34 is mounted to the arm 28 to support the primary 20 in a position generally encircling the secondary housing 25 of the lamp assembly 14. The illustrated pedestal 30 and shaft 32 are provided with a desired aesthetic appearance. The present invention is easily adapted for use with lamps of a wide variety of designs. Accordingly, the design and configuration of the illustrated base 12 should not be interpreted as a limitation on the present invention. The power supply circuit 18 may be a conventional inductive power supply circuit, however, in one embodiment, the power supply circuit 18 includes a resonance seeking ballast, such as the ballast disclosed in U.S. application Ser. No. 10/246,155 entitled “Inductively Coupled Ballast Circuit,” which was filed on Sep. 18, 2002, and is incorporated herein by reference. In the illustrated embodiment, the principle components of the power supply circuit 18 are housed within the void 31 in pedestal 30, for example, as shown in FIG. 3. The location of the components of the power supply circuit 18 may, however, vary from application to application depending primarily on the lamp design and desired aesthetics. For example, the principle components of the power supply circuit 18 can alternatively be disposed at other locations in or on the pedestal 30 or may be disposed in or on the shaft 32. As a further alternative, some or all of the components of the power supply circuit 18 can be integrated into a wall plug (not shown) for the lamp 10. In the illustrated embodiment, the primary 20 is generally ring-shaped and is mounted within a generally ring-shaped primary housing 34. The primary housing 34 defines a central opening 35 that is of sufficient dimension to receive at least a portion of the lamp assembly 14. The size, shape and orientation of the primary 20 (and primary housing 34) can vary from application to application depending in part on the specific design characteristics of the lamp or other inductive device. In the described embodiment, the primary 20 has an inner diameter of 1.25 inches and includes 50 turns of wire 63 wrapped circumferentially around a generally conventional plastic bobbin 33. The wire 63 may be straight 26-gauge wire. Additionally, in this particular embodiment, the values of capacitors 271 and 272 in the above-referenced patent application are 66 nF. The lamp assembly 14 generally includes a light source 26, such as an incandescent bulb, that is powered by a secondary circuit 22 (See FIGS. 4 and 5). In this embodiment, the light source 26 is custom formed to provide the desired aesthetic appearance. The upper end of the light source 26 is shaped to define a small ring 28 that permits the light source 26 to be hung from a hook 36 defined at the end of shaft 32. The custom-formed lamp of the illustrated embodiment is merely exemplary, and the light source 26 may vary from application to application as desired. As an alternative to the custom-formed lamp 26, the lamp assembly 14 may include a conventional lamp (not shown) that is contained within a housing (not shown) designed to provide the desired aesthetic appearance. For example, the custom-shaped light source 26 can be replaced by a standard incandescent light source that is installed within an ornate and aesthetically pleasing housing. In this alternative embodiment, the secondary circuit 22 may also be enclosed within the housing. As noted above, the lamp assembly 14 includes a secondary circuit 22 that provides power to the lamp 26. The secondary circuit 22 includes a secondary 24 that is inductively driven by the primary 20. A schematic diagram of the secondary circuit is shown in FIG. 5. In this embodiment, the light source 26 is a custom-formed incandescent 30-watt bulb. The light source 26 is electrically connected in series with the secondary 24 and, if desired, a capacitor 60. In this embodiment, the secondary 24 has a diameter of 0.25 inches and includes 24 turns of wire 64 wrapped circumferentially around a generally conventional plastic bobbin 62. The wire 64 may be straight 26-gauge wire. The optional capacitor 60 is intended to improve the power factor of the secondary circuit 22 by offsetting the inductance of the secondary 24, as described in more detail in U.S. application Ser. No. 10/133,860 entitled “Inductively Powered Lamp Assembly,” which was filed on Apr. 26, 2002 and is incorporated herein by reference. In this embodiment, the capacitor 60 includes a capacitance of 33 nF. The characteristics of the secondary circuit 22, including the secondary 24 and the capacitor 60, may vary from application to application depending primarily on the characteristics of the light source and the power supply. In fact, as noted above, the capacitor 60 is optional and may be eliminated altogether in some applications. Although this embodiment includes an incandescent light source 26, the present invention can alternatively include essentially any other electromagnetic radiation emitting device, such as a gas discharge bulb or a light emitting diode. As described above, the desk lamp 10 is provided with a mechanical dimmer 16 for controlling the brightness of the light source 26. In the illustrated embodiment, the mechanical dimmer 16 is incorporated into the base 12 and shaft 32 to provide vertical movement of the primary housing 34 (and consequently the primary 20) and vary the physical distance between the primary 20 and the secondary 24. As shown, the primary housing 34 is mounted on movable arm 28. In this embodiment, the arm 28 extends through a vertical slot 50 in the shaft 32 and is connected to the rack 72 of a rack-and-worm assembly 70. In this embodiment, the lamp base 12 may include a dial 66a (See FIG. 7), a slider 66b (See FIG. 8) or a rotating top 66c (See FIG. 9) for controlling movement of the mechanical dimmer 16. The rack-and-worm assembly 70 translates rotational movement of the dial 66a, slider 66b or rotating top 66c into vertical movement of the primary 20 in accordance with conventional mechanical principles. More specifically, movement of dial 66a, slider 66b or rotating top 66c causes rotation of worm gear 74, which is rotatably fixed within the lamp base 12 or shaft 32. In the illustrated embodiment, dial 66a is connected to worm gear 74 by spur gear 68. As a result, rotational movement of dial 66a causes rotational movement of spur gear 68 and ultimately worm gear 74. Movement of worm gear 74 in turn causes vertical linear movement of the rack 72 and consequently the primary 20. As perhaps best shown in FIG. 6, the rack 72 includes longitudinal slots 73 that are interfitted with corresponding ribs (not shown) on the interior of the shaft 32. This interface permits vertical movement of the rack 72 within the shaft 32. Because of the non-reversible nature of a worm gear assembly (i.e. the worm 74 can move the rack 72, but the rack 72 cannot rotate the worm gear 74), it provides a “self-locking” mechanical dimmer 16. The electrical leads (not shown) running from the power supply circuit 18 to the primary housing 34 are provided with sufficient slack to permit the desired range of motion. Alternatively, sliding contacts (not shown) can be provided to maintain an electrical connection between the power supply circuit 18 and the primary 20 throughout the entire range of motion of the mechanical dimmer 16. An alternative mechanical dimmer 80 is shown in FIG. 10. In this alternative embodiment, the inner end of the arm 82 includes a nut 84 that is movable mounted over a threaded rod 86. The height of the arm 82 is adjusted by rotating the threaded rod 86, which causes the nut 84 to move up and down the shaft of the rod 86. The rod 86 may be rotated using essentially any type of control, such as dial 66a, slider 66b or rotating top 66c. As with the rack-and-worm embodiment described above, slack electrical leads, sliding contacts or other similar mechanisms can be provided to maintain electrical connection throughout the desired range of motion of the arm 82. The mechanical dimmer may alternatively be configured to provide movement of the lamp assembly 14 with respect to the primary 20. This alternative may be preferable in some applications because it may simplify the electrical configuration of the system. More specifically, because there is no relative movement between the power supply circuit 18 and the primary 20, wires or other electrical connections can be run directly from the power supply circuit 18 to the primary 20 without any accommodation for relative movement (e.g. slack electrical leads or sliding contacts). Further, because the lamp assembly 14 is self contained, there is no need to run electrical connections to the lamp assembly 14. In one embodiment of the desk lamp 10′ manufactured in accordance with this alternative, the shaft 32′ includes a plurality of notches 40a-c′ capable of receiving the lamp assembly 14′ (See FIGS. 11a-b and 12). In this embodiment, the upper end of the lamp assembly 14′ is provided with an enlarged ring 38′ capable of being fitted into the notches 40a-c′. As illustrated, the lamp assembly 14′ can be suspended from different notches 40a-c′ to vary the position of the secondary housing 25′ with respect to the primary housing 34′. This in turn varies the brightness of the lamp assembly 14′. In a second embodiment of an alternative desk lamp 10″, the shaft 32″ is manufactured from a flexible material that is capable of bending to vary the position of the lamp assembly 14″ with respect to the primary housing 34″, and consequently the position of the secondary with respect to the primary. In some applications, the flexible shaft 32″ may have little or no resiliency so that it remains in whatever position it is bent into under acted on. In other applications, the flexible shaft 32″ may be resilient so that a mechanism is required to hold the shaft 32″ in the desired position. In one embodiment of this type of application shown in FIGS. 13-16, a weight 42″ is fitted over and movable along the shaft 32″ to set and maintain the shaft 32″ at the desired bend (See FIGS. 13 and 16). In one embodiment, the weight 42″ is fitted over the shaft 32″ and includes a generally conventional, spring-loaded binding clip 50″ that selectively locks the weight in place on the shaft 32″. In operation, spring 52″ biases the binding clip 50″ into a binding position on the shaft 32″. To move the weight, the binding clip 50″ is pushed against the bias of spring 52″ into a released position in which the binding clip 50″ is free to slide along the shaft 32″. In a third embodiment of the desk lamp 10′″, a counterbalance assembly 44′″ is used to set the position of the lamp assembly 14′″. In this embodiment, the shaft 32′″ is preferably hollow, defining an internal space (not shown) to contain the counterbalance assembly 44′″. The lamp assembly 14′″ is suspended from the shaft 32′″ by a cable 48′″. The cable 48′″ extends through the internal space in the shaft 32′ and is fixed to the counterbalance assembly 44′″. A ring 40′″ is mounted to the free end of the cable 48′″ to interconnect with the lamp assembly ring 38′″. As best shown in FIG. 18, the counterbalance assembly 44 generally includes a spring 50′″ (or other biasing mechanism) with a tension that offsets the weight of the lamp assembly 14′″. The counterbalance assembly 44 also includes a pair of rollers 52a-b′″ that firmly entrap the cable 48′″. The rollers 52a-b′″ are fitted with Beilville washers 54a-b′″ to provide a limiting brake that retains the cable 48′″ in a given position (See FIG. 19). By offsetting the weight of the lamp assembly 14″, the counterbalance assembly 44 holds the lamp assembly 14′″ in the position selected by the user. This allows the user to set the brightness of the lamp assembly 14′″ simply by raising or lowering the lamp assembly 14′″. Alternatively, the spring 50′″ can be replaced by a counterbalance weight (not shown) having approximately the same weight as the lamp assembly 14′″. In a further alternative embodiment (not shown), the mechanical dimmer may include a mechanism for moving the secondary within the lamp assembly rather than moving the entire lamp assembly. For example, the lamp assembly may include a secondary that is slidably movably mounted along a fixed shaft so that the user can slide the secondary up or down the shaft to control the brightness of the lamp assembly (not shown). Alternatively, the secondary may be rotatably mounted within the secondary housing to permit changes to the angular orientation of the secondary, for example, by mounting the secondary on a ball joint (not shown). Knobs or handles (not shown) may protrude through slots in the secondary housing to facilitate the linear or angular movement. The mechanical dimmer may alternatively include a similar mechanism (not shown) for moving the primary within the primary housing. An alternative inductively powered lamp 100 is shown in FIGS. 20-22. In this embodiment, the amount of power supplied to the secondary component is controlled by varying the relative angular orientation of the secondary 124 with respect to the primary 120. The lamp 110 generally includes a pedestal 130, a shaft 132 mounted to the pedestal 130 and an arm 133 pivotally mounted to the shaft 132. In one embodiment, light source 126 is located toward one end of arm 133, and a counterbalance 150 is located toward the opposite end. The power supply circuit is preferably contained primarily in the pedestal 130 and the shaft 132, and includes a primary 120 that is mounted toward the top of the shaft 132 in a ring-shaped primary housing 134. The primary housing 134 may be assembled from injection molded halves 134a-b. A support 140 extends upwardly from the shaft 132 into the central opening defined by the primary housing 134. The support 140 defines a concave cradle 142 adapted to receive the arm 133. The arm 133 includes a sphere 146 disposed at the center of gravity of the arm 133. The sphere 146 may be assembled from injection molded halves 146a and 146b, and includes an outer diameter that corresponds with the inner diameter of the cradle 142. Accordingly, the arm 133 is mounted to the shaft 132 by resting it upon the support 140 with sphere 146 received in cradle 142. If desired, the stability of the arm 133 may be improved by heavily weighting the sphere 146. The illustrated connection permits pivotal movement of the arm 133 in essentially all directions. A variety of alternative joints can be used to connect the arm 133 to the shaft 132. For example, a standard ball and socket or a standard universal joint can replace the illustrated connection. If desired, a connection providing only limited movement of the arm 133, such as only vertical or only horizontal movement, may be used. In operation, the arm 133 is pivotally moved with respect to the shaft 132 causing a rolling action of sphere 146 within cradle 142. As the arm 133 is moved, the secondary 124 pivots within the magnetic field generated by the primary 120. This varies the coupling coefficient and the brightness of the light source 126. The secondary 124 and primary 120 can be oriented to provide the brightest light at the desired position of the arm 133. For example, the light source 126 may be its brightest when the arm 133 is substantially horizontal and increasingly dim as the arm 133 is moved up or down out of the horizontal position. Alternatively, the light source 126 may become brighter as the arm 133 is moved downward below horizontal. Counterbalance 150 is provided to counter the weight of light source 126, thereby maintaining the relative position of arm 133 unless acted upon. The previously described embodiments are directed to lighting applications in which the brightness of the light source is controlled by mechanisms that vary the relative position of primary and secondary. The present invention is not, however, limited to lighting application. Rather, the present invention is well suited for use in essentially any application when control over the amount of power supplied to a device is desired. In this aspect, the present invention provides an infinitely adjustable inductive power supply. By providing a mechanism for controlling the position of the secondary with respect to the primary, the amount of power supplied through the inductive coupling can be controlled. More specifically, by adjusting the distance between the primary and the secondary or the angular orientation between the primary and the secondary, the coupling coefficient of the inductive coupling can be infinitely adjusted within the range of the inductive power supply. In this aspect, the present invention not only provides an infinitely adjustable power source, but it also provides isolation between the power supply and the inductively powered device, thereby providing safety benefits. An adjustable power supply in accordance with the present invention is described in more detail in connection with the variable speed fan 200 shown in FIG. 23. In the illustrated embodiment, the fan 200 includes a conventional electric motor 280 that is housing within a generally conventional fan housing 282. The fan 200 includes a plurality of fan blades 284a-c that are mounted to the rotor (not shown) of the electric motor 280. The electric motor 280 receives power from a power supply circuit 218 having a primary 220 and a secondary 224. The secondary 224 is movably mounted adjacent to the primary 220 so that movement of the secondary 224 can be used to selectively vary the coupling coefficient of the inductive coupling and, in turn, vary the power supplied to the motor 280. For example, in the illustrated embodiment, the secondary 224 is mounted to adjustment rod 290. The adjustment rod 290 is movable inwardly and outwardly with respect to the fan housing, as indicated by arrow A, to move the secondary 224 with respect to the primary 220. As a result, adjustment of the secondary 224 can be used to selectively control the speed of the fan 200. Although this embodiment includes a mechanism for moving the secondary 224, the coupling coefficient can alternatively be adjusted by providing a mechanism for moving the primary 220 or for moving both the primary 220 and the secondary 224. As noted above, adjustment of the coupling coefficient can be achieved by varying the physical distance between the primary and the secondary and/or by varying the relative angular orientation between the primary and the secondary. Although described in connection with a variable speed fan, the infinitely adjustable power supply of the present invention is well suited for use in other applications where an adjustable power supply is desired. For example, the power supply may be incorporated into a battery charger (not shown), where the magnitude of the charging power is controlled by adjusting the relative position of the primary and the secondary. As a further example, the power supply may be incorporated into an electric drill (not shown) or other electric power tool, where the power supplied to the electric motor is adjusted by selectively varying the relative position between the primary and the secondary. In another embodiment, a desk lamp 300 is provided with a lamp assembly 314 that can be positioned in different orientations to vary the characteristics of the light output. In the embodiment illustrated in FIGS. 24 and 25, the desk lamp 300 includes a lamp assembly 314 that can be positioned in either an upright or inverted position with the two positions creating different lighting effects. As shown, the desk lamp 300 includes a base 312 having a pedestal 330, a shaft 332 and a primary housing 334. The primary housing 334 encloses the primary 320 and provides an annular structure for supporting the lamp assembly 314. In the illustrated embodiment, a transparent plate 340 is mounted within the primary housing 334 to receive the lamp assembly 314. The plate 340 defines a central opening 342 to nest the lamp assembly 314. In this embodiment, the lamp assembly 314 is generally “egg-shaped” having a pair of light transmissive housing components disposed on opposite sides of a support ring 360. More specifically, the lamp assembly 314 includes a transparent housing portion 362 and a translucent housing portion 364. A separate light source, such as incandescent bulbs, may be positioned within each housing portion 362 and 364 or a single light source may be provided to cast light through both housing portions 362 and 364. The housing portions 362 and 364 each have an external diameter that is smaller than the internal diameter of the central opening 342 in the plate 340. The external diameter of the support ring 360 is, however, greater than the internal diameter of the central opening 342. As a result, the lamp assembly 314 can be suspended within the central opening 342 upon the support ring 360. In use, the character of the light emitted by the lamp 300 can be varied by placing the lamp assembly 314 into the central opening 342 in different orientations. In particular, placing the lamp assembly 314 with the transparent housing portion 362 facing downwardly causes the desk lamp 300 to cast bright, clear light onto the surface below, while casting soft, diffuse light upwardly away from the surface. Inverting the lamp assembly 314 and placing it with the translucent housing portion 364 facing downwardly causes the desk lamp 300 to cast soft, diffuse light downwardly onto the surface below, and bright, clear light upwardly away from the surface. Variations in the light cast by the lamp 300 can also be achieved by providing the housing portions 362 and 364 with different physical and optical characteristics. For example, the two housing portions 362 and 364 can be manufactured from different color materials, have different sizes or shapes or be formed with different lens characteristics, such as variations in focus, magnification and diffusion. Alternatively, differences in the light cast by the lamp 300 can be achieved by providing different light sources within housing 362 and 364. For example, the two light sources may have different wattage or be of different lamp types. In one embodiment, housing 362 is manufactured from clear glass or polymer, and contains a white incandescent bulb, while housing 364 is manufactured from a translucent glass or polymer, and contains a blue LED. If desired, the physical distance between the primary and secondary can also be varied by placing the lamp assembly 314 into the central opening 342 in different positions. If the secondary 324 is axially aligned with the support ring 360, then the secondary 324 will be in substantially the same position with respect to the primary 320 regardless of whether the transparent portion 362 or the translucent portion 364 is facing upwardly. On the other hand, if the secondary coil 324 is axially offset from the support ring 360, the physical distance between the primary 320 and the secondary 324 will vary depending on the orientation of the lamp assembly 314. The secondary 324 can be offset from the support ring 360 in either direction depending on the position in which more light output is desired. In yet another aspect, the present invention is incorporated into a replacement lamp base 400 intended to work in existing screw-base lamps. As shown in FIG. 26, the lamp base 400 includes a housing 402 containing a power supply circuit 418 that drives a primary 420. In the illustrated embodiment, the housing 402 is manufactured from two injection-molded halves that close about the power supply circuit 418 and the primary 420. The housing 402 also includes a screw base 404 that is generally identical to the existing screw-base of conventional incandescent lamps. The screw base 404 is fitted over a lower portion of the housing 402 so that it can be easily screwed into a conventional lamp socket (not shown). Electrical leads (not shown) extend from the screw base 404 to the power supply circuit 418 through corresponding openings in the housing 402. The housing 402 defines a lamp receptacle 408 adapted to receive an inductive lamp assembly 414. The receptacle 408 may include a mechanical dimmer that permits the user to mechanically vary the respective position between the primary and the secondary (See FIGS. 27 and 28). A mechanical dimmer is not, however, necessary, and the receptacle 408 may include a bayonet fitting or other conventional fitting to secure the lamp assembly 414 within the receptacle 408 in a fixed position. In the alternative embodiment shown in FIGS. 27 and 28, the receptacle 408′ includes cams 410a-b′ that permit the position of the lamp assembly 414′ to be mechanically varied. The cams 410a-b′ interact with corresponding cams 412a-b′ on the undersurface of the secondary housing 403′, as described in more detail below. The cams 410a-b′ and 412a-b′ may be replaced by threads or other similar mechanisms (not shown) for mechanically selectively varying the depth of the lamp assembly 414′ within the receptacle 408′. To help to retain the lamp assembly 414 in the desired position within the receptacle 408, the receptacle 408 and the secondary housing 403 are configured to be frictionally interfitted with one another. In this embodiment, a resilient o-ring 440 may be fitted around the secondary housing 403 to provide a firm frictional interface. The o-ring 440 is preferably seating within an annular recess (not shown) to help prevent it from sliding up or down the housing 403. Alternatively, the o-ring 440 may be fitted within an annular recess (not shown) in the receptacle 408. As a further alternative, the mechanical dimmer may include a mechanism for moving the primary 420 within the housing 402 or the secondary 424 within the secondary housing 403. For example, either coil may be slidably movable along its axis within its corresponding housing to vary the distance between the primary and the secondary, or either coil may be pivotally movable within its housing to vary the angular orientation between the primary and the secondary. The power supply circuit 418 may be generally identical to the power supply circuit 18 described above, with component values selected to match the desired light source or range of light sources. Referring now to FIG. 26, the lamp assembly 414 generally includes a secondary housing 403 that is adapted to be fitted within the lamp receptacle 408, a secondary circuit (not shown) contained within the secondary housing 425, and a light source 426 protruding from the secondary housing 425. The secondary housing 425 generally includes two injection molded halves that are closed around the secondary 424 and the remainder of the secondary circuit (not shown). As noted above, the secondary housing 403′ of the alternative embodiment shown in FIG. 27 includes cams 412a-b′ on its undersurface to interact with the cams 410a-b′ of the receptacle 408. The cams 412a-b′ may be eliminated or replaced with other mechanical dimming mechanisms. The secondary circuit is preferably generally identical to the secondary circuit 22 described above, with its component values selected to correspond with the desired light source 426. In an alternative embodiment, the present invention is incorporated into inductively powered wind chimes 500 that provide both and audible and visual response to the wind (See FIGS. 29-31). In general, the wind chime 500 includes a primary housing 512 that is suspended from a hanging ring 504 and a plurality of chime assemblies 514a-d that are suspended from the hanging ring 504 within the center of the primary housing 512. The primary housing 512 is suspended from the hanging ring 504 by wires 502a-d or other similar components. The hanging ring 504 is configured to permit the wind chimes 500 to be hung in a wide variety of locations. In the illustrated embodiment, the primary housing 512 includes two injection molded halves 512a-b that house the primary 520 (See FIG. 30). The power supply circuit (not shown) is contained within the wall plug (not shown). The power supply circuit 518 may be generally identical to the power supply circuit 18 described above, with component values selected to match the desired light source or range of light sources. Each chime assembly 514a-d is suspended within the center of the primary housing 512 by a corresponding wire 506a-d. The separate wires 506a-d permit each chime assembly 514a-d to move freely in response to the wind. Each chime assembly 514a-d generally includes a chime housing 530, a light source 526, a secondary circuit 522 and a chime 532. The chime housing 530 of the illustrated embodiment includes an opaque upper housing portion 530a that is suspended from the corresponding wire 506a-d and a transparent lower housing portion 530b that is mounted to the undersurface of the upper housing portion 530a. The chime housing 530 defines an internal space for containing the secondary circuit 522, including the secondary 524, the light source 526 and any desired capacitor 528. The secondary circuit 522 is housed within the upper portion 530a where it is largely hidden from sight. The light source 526 extends from the upper housing portion 530a down into the lower housing portion 530b. The chime 532 is a generally conventional chime and is mounted to the lower end of each chime housing 530. As a result, as the chime assemblies 514a-d move in the wind, the chimes 532 collide with one another to create sound. At the same time, as each chime assembly 514a-d moves, its secondary 524 moves toward and away from the primary 520. The movement of the secondary 524 within the magnetic field generated by the primary 520 varies the amount of power supplied to the light source 526, and consequently the brightness of the light source 526. More specifically, as a chime assembly 514a-d moves closer to the primary 520, the amount of power transferred by the primary 520 to the secondary 524 increases and the light source 526 becomes brighter. Conversely, as a chime assembly 514a-d moves away from the primary 520, the amount of power transferred to the secondary 524 decreases and the light source 526 becomes dimmer. As a result, increased wind causes increased movement of the chime assembly 514a-d and increased undulations in the brightness of the light sources 526. In a further aspect, the present invention relates to an inductive power supply station having a primary that inductively provides power to one or more inductively powered devices, each having its own secondary coil. In the embodiment illustrated in FIGS. 32-35, the inductive power supply station 600 generally includes a power receptacle 602 and a storage receptacle 608 that are supported by a plurality of legs 606a-c. A primary 620 is disposed around the power receptacle 602 to generate a magnetic field that provides inductive power to any inductive devices 650a-c placed within the power receptacle 602. In the described embodiment, the primary 620 has a diameter of 6.5 inches and includes 50 turns of wire 663 wrapped circumferentially around a generally conventional plastic bobbin 633. The wire 663 may be litz wire consisting of eight strands of 32-gauge insulated wire wrapped 1 turn per inch, which may provide the primary 620 with improved efficiency. The primary 620 is contained within primary housing 634. Referring now to FIG. 33, the primary housing 634 includes two annular halves 634a and 634b that enclose the primary 620. The power receptacle 602 is intended to receive a plurality of inductive devices, such as lamp assemblies 614a-b, at random locations and random orientations. In the illustrated embodiment, the power receptacle 602 is bowl-shaped and is manufactured from a transparent or translucent material, such as glass or plastic. The bowl-shaped power receptacle 602 is fitted within and supported by the primary housing 634. Although the illustrated power receptacle 602 is bowl-shaped, the receptacle may have a variety of alternative constructions. For example, the bowl-shaped receptacle 602 may be replaced by horizontal surface (not shown) upon which inductively powered devices can be placed or it may be replaced by one or more rings from which inductively powered devices can be suspended. As a further example, the receptacle may be a vertical surface adjacent to which various inductive devices can be suspended, such as an inductively powered wall lamp or an inductively powered clock. As noted above, the illustrated power supply station 600 also includes a storage receptacle 608 mounted to legs 606a-c, for example, by screws or other fasteners. The storage receptacle 608 provides a place for storing lamp assemblies, such as lamp assembly 614c, and other inductively powered devices when they are not in use. In this embodiment, the storage receptacle 608 is bowl-shaped, to complement the shape of the power receptacle 602, and is mounted between the legs 606a-c of the station 600 below the power receptacle 602 and above the base 612. The size, shape, configurations and location of the storage receptacle may vary from application to application as desired. Alternatively, the storage receptacle 608 may be eliminated. The power supply station 600 also includes a power supply circuit 618 that supplies power to a primary 620. In the illustrated embodiment, the power supply circuit 618 is disposed within lamp base 612. Referring now to FIG. 34, the lamp base 612 generally includes an upper housing 612a and a lower housing 612b that enclose the power supply circuit 618. The power supply circuit 618 includes a power switch 690 that is actuated by button 692. The button 692 extends down through a corresponding aperture 694 in the upper housing 612a to engage the switch 690. The button 692 may be translucent and the power supply circuit 618 may include a pair of power-indicating LEDs 696a-b that illuminate the button 692 when the power is on. In this embodiment, a power supply cord 698 penetrates the lower housing 612b and is electrically connected to power-in socket 699 to provide AC power to the power supply circuit 618. Electrical leads (not shown) extend from the power supply circuit 618 to the primary 620 through a wiring channel (not shown) in one of the legs 606a-c. The power supply circuit 618 is preferably identical to power supply circuit 18 described above. This power supply circuit 618 has the ability to monitor the power supplied to the primary 620 to determine certain characteristics of the cumulative load (e.g. the inductively powered devices placed in the power receptacle 602), and then to adjust the characteristics of the power supplied to the primary 620 as a function of the monitored values. In one embodiment, the power supply circuit 618 monitors the current supplied to the primary 620 and adjusts the frequency of the power supplied to the primary 610 based on the value of the current. In the illustrated embodiment, the inductively powered devices are a plurality of lamp assemblies 614a-c. As perhaps best shown in FIG. 35, each of the lamp assemblies 614a-c generally includes a lamp housing 604 that encloses a light source 626a-d and a secondary circuit 622. In this embodiment, the lamp housing 604 is assembled from two glass or injection-molded plastic halves 604a-b, at least one of which is manufactured from a transparent or translucent material. The halves 604a-b are interconnected by cover ring 640, for example, by adhesives or threads. A separate o-ring 642a-b may be fitted between the cover ring 640 and each half 604a-b. The secondary circuit 622 is enclosed within the lamp housing 604, and generally includes a secondary 624 and an optional capacitor 630 that are connected in series with light source 626a-d. In the illustrated embodiment, the light source includes a plurality of LEDs 626a-d. In this embodiment, the secondary 624 has a diameter of 2 inches and includes 27 turns of 26-gauge straight wire 664 wrapped circumferentially around a generally conventional plastic bobbin 662. The characteristics of the secondary 624 (e.g. number of turns, diameter of coil, type of wire) and optional capacitor 630 (e.g. capacitance value) are selected to correspond with the light source 626a-d and the power supplied by the primary 620. To improve the flexibility of the inductive power supply station, an inductive device may include a secondary having a plurality of coils that are arranged at different orientations. In applications where only a single coil is used, it is possible that a device randomly placed within a power receptacle will be located with the coil oriented substantially parallel to the magnetic field. In such situations, the secondary may not receive sufficient power to power the device from the primary. The use of multiple coils addresses this problem by providing a secondary coil arrangement that significantly increases the likelihood that at least one coil will at least substantially intersect the flux lines of the magnetic field generated by the primary. For example, an inductive device may include a secondary with two coils that are oriented at 90 degrees to one another. With this configuration, at least one of the two coils is likely to extend across the flux lines of the magnetic field and receive power from the primary. The number of separate coils may vary from application to application, for example, the inductive device may include 3, 4, 6 or 8 coils at different orientations to provide improved efficiency in a wide variety of orientations. By providing a sufficient number of coils at different orientations, the inductive device can be configured to receive power from the primary regardless of the orientation of the inductive device. In one embodiment, the inductively power device includes a secondary 670 having three separate coils 672a-c; one oriented along each of the x, y and z axes of a Cartesian three-dimensional coordinate system. As shown in FIG. 36, an arrangement of three bobbins 660a-c is provided to receive the three coils 672a-c. The diameters of the three bobbins 660a-c vary so that the bobbins 660a-c can be fitted one within the other. Given that the power induced in a secondary is proportional to the diameter of the secondary, the use of differently sized bobbins may result in an imbalance in the power supplied to each secondary. In applications where it is desirable to balance the power induced in the different coils 672a-c, additional turns of wire can be added to the smaller bobbins 660b-c, with the precise number of additional turns added to each smaller bobbin depending primarily on its size. For example, if the outermost secondary 672a includes seven turns, it may be desirable to include eight turns on the middle secondary 672b and nine turns on the innermost secondary 672c. Alternatively, a spherical bobbin (not shown) can be provided, with each coil being wrapped about the spherical bobbin at the desired location and in the desired orientation, for example, about the x, y and z axes. This embodiment reduces the differences in the diameters of the three secondaries, thereby improving the balance of the coils. Although the secondary with multiple coils is described in connection with the inductively powered lamp assembly 614, a secondary with multiple coils can be incorporated into essentially any inductively power device to maximize power transfer in various orientations of the device within the magnetic field. For example, a cell phone (not shown) or personal digital assistant (not shown) can be provided with an inductively powered battery charger having a secondary with a single coil, such as secondary 622 above, or with multiple coils, such as secondary 670. In this example, a cell phone or personal digital assistant having a secondary with multiple coils can be placed randomly within the power receptacle 602 without concern for its orientation because the secondary 670 will be able to obtain sufficient power to charge the device in any orientation. FIGS. 38a-c show circuit diagrams for three embodiments of the three-coil secondary 670. FIG. 38a illustrates a circuit 680 that provides DC power from three separate coils 672a-c. As shown, the three coils 672a-c are connected in parallel to the load, a capacitor 674a-c is connected in series between each coil 672a-c and the load. In this embodiment, the value of each capacitor 674a-c and each diode 676a-c is selected to provide a resonant circuit for the load-side of the circuit. This circuit 680 combines the power induced within each of the coils using the capacitors to provide resonance with the load, and diodes 674a-c rectifying the voltage output from circuit 680. Alternatively, diodes 676a-c can be eliminated from the circuit 680 to provide AC power to the load. FIG. 38b illustrates a half wave rectifier circuit 680′ that provides DC power from three separate coils 672a-c′. As shown, the three coils 672a-c′ are connected in parallel to the load through an arrangement of diodes 676a-f′ is connected in series between each coil 672a-c′ and the load. In this embodiment, the value of each diode 676a-f′ is determined based primarily on the characteristics of the load. Additionally, a capacitor 674a-c′ is connected in series between one side of the coil 672a-c′ and the corresponding diodes 676a-f′. The value of each capacitor 674a-c′ is also determined based primarily on the characteristics of the load. This circuit 680′ combines the power induced within each of the coils using the capacitors to provide resonance with the load, and diodes 676a-c rectifying the voltage output from the circuit 680′. FIG. 38c illustrates a full wave rectifier circuit 680″ that provides DC power from three separate coils 672a-c″. As shown, the three coils 672a-c″ are connected in parallel to the load through an arrangement of diodes 676a-l″ is connected in series between each coil 672a-c″ and the load. In this embodiment, the value of each diode 676a-l″ is determined based primarily on the characteristics of the load. Additionally, a capacitor 674a-c″ is connected in series between one side of the coil 672a-c″ and the corresponding diodes 676a-l″. The value of each capacitor 674a-c″ is determined based primarily on the characteristics of the load. All three of these circuit 680, 680′ and 680″ perform the function of providing DC power. Circuit 680 is likely the least expensive design, while circuit 680″ provides the best control over the DC output, for example, circuit 680″ likely provide less fluctuation in the output compared to the other two embodiments. In use, the illustrated inductive power supply station 600 and accompanying light assemblies 614a-c provide a distinctive and aesthetically pleasing light source. The amount and character of light cast by the system can be adjusted by varying the number of lamp assemblies 614a-c placed within the receptacle 602, by varying the position of each lamp assembly 614a-c and by varying the orientation of each lamp assembly 614a-c within the receptacle. For example, additional lamp assemblies 614a-c can be added to the receptacle to increase the brightness of light cast by the system. Similarly, the location or orientation of a given lamp assembly 614a-c can be varied to control the light output of that particular lamp assembly 614a-c. In an alternative embodiment, the lamp assembly 614 includes two light sources 626a-b that are connected to separate secondaries 624a-b (See FIG. 37). In this embodiment, the two light sources 626a-b are preferably light emitting diodes, each generating light of a different color. The secondaries 624a-b are oriented 90 degrees from each other so that the power supplied to one secondary is inversely proportional to the power supplied to the other secondary. For example, by rotating the lamp assembly 614 with the power receptacle 602, one secondary is moved into a position that more directly intersects the magnetic field generated by the primary 620 while the other is moved to a position that less directly intersects the magnetic field. As a result, the lamp assembly 614 can be rotated within the power receptacle 602 to selectively control the color of the lamp assembly 614 by adjusting the amount of power supplied to each light source 626a-b. For example, with red and blue light sources, the lamp assembly 614 can be rotated to cast light ranging from pure red through purple to pure blue. If desired, a device can be provided with 3 separate secondaries, each oriented 90 degrees from one another, such as along each of the x, y and z axes of a Cartesian three-dimensional coordinate system. In accordance with this alternative, each secondary can drive a separate light source or power a separate electrical device. It should also be noted that the 3 axis configuration can be used to calculate the orientation of the device by comparing the voltages from each secondary. In some applications, it may be desired to provide an inductively powered device with two sets of coils, a first to set to provide power to one or more devices and a second to provide position information. FIGS. 39a-d illustrate circuit diagrams for various multiple secondary circuits. FIG. 39a illustrates a simple three secondary circuit 700 in which each coil 702a-c is connected to a separate load, such as a light source, a single channel of a three-channel position calculating circuit or other inductively powered device. FIG. 39b illustrates an alternative circuit 710 in which a capacitor 714a-c is connected in series between each secondary 712a-c and its corresponding load. In this embodiment, the capacitance value of each capacitor 714a-c is selected primarily as a function of the corresponding load and the inductance of the corresponding secondary to tune the power within each secondary circuit. FIG. 39c illustrates an alternative circuit 720 in which a capacitor 724a-c and a diode 726a-c are connected in series between each secondary 722a-c and its corresponding load. This circuit 720 provides limited rectification to provide a separate source of DC power to each load. In this embodiment, the capacitance value of each capacitor 724a-c and diode 726a-c is selected primarily as a function of the corresponding load and the inductance of the corresponding secondary. FIG. 39d illustrates an alternative circuit 730 in which a capacitor 734a-c and a pair of diodes 736a-f are connected in series between each secondary 732a-c and its corresponding load. This circuit 730 provides half wave rectification to provide a separate source of DC power to each load. In this embodiment, the capacitance value of each capacitor 724a-c and diode 726a-c is selected primarily as a function of the corresponding load and the inductance of the corresponding secondary. Although not illustrated, each secondary may alternatively include a full wave rectification circuit to provide a separate source of DC power to each load. Although the inductive power supply station 600 is illustrated in connection with a unique lamp construction, the inductive devices may include other types of inductively powered devices. For example, a cell phone, personal digital assistant or other similar device may include an inductively powered battery charger that is configured to receive power from the inductive power supply station. In such applications, the inductively powered devices can be charged simply by placing it within the power receptacle. The inductively powered device may use the power supplied by the secondary to directly power, rather than simple recharge, the device. For example, a miniature radio, MP3 music player or other media player can be provided with inductive secondary circuits, permitting them to be powered by the power supply station. The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to wireless power supplies, and more particularly to inductively powered devices. The principles of inductive power transfer have been known for many years. As a result of mutual inductance, power is wirelessly transferred from a primary coil (or simply “primary”) in a power supply circuit to a secondary coil (or simply “secondary”) in a secondary circuit. The secondary circuit is electrically coupled with a device, such as a lamp, a motor, a battery charger or any other device powered by electricity. The wireless connection provides a number of advantages over conventional hardwired connections. A wireless connection can reduce the chance of shock and can provide a relatively high level of electrical isolation between the power supply circuit and the secondary circuit. Inductive couplings can also make it easier for a consumer to replace limited-life components. For example, in the context of lighting devices, an inductively powered lamp assembly can be easily replaced without the need to make direct electrical connections. This not only makes the process easier to perform, but also limits the risk of exposure to electric shock. The use of inductive power transfer has, however, for the most part been limited to niche applications, such as for connections in wet environments. The limited use of inductive power transfer has been largely the result of power transfer efficiency concerns. To improve the efficiency of the inductive coupling, it is conventional to carefully design the configuration and layout of the primary and secondary coils. The primary and the secondary are conventionally disposed within closely mating components with minimal gap between the primary and the secondary. For example, the primary is often disposed within a base defining a central opening and the secondary is often disposed within a cylindrical component that fits closely within the central opening of the base. This and other conventional constructions are design to provide close coaxial and radial alignment between the primary coil and the secondary coil. Several specific examples of patents that reflect the conventional approach of providing a fixed, predetermined physical relationship between the primary and secondary coils include: U.S. Pat. No. 5,264,997 to Hutchisson et al, which discloses an inductive lamp with coaxial and closely interfitting primary and secondary coils; U.S. Pat. No. 5,536,979 to McEachern et al, which discloses an inductive charging device in which the device to be charged is fitted closely within a cradle to position the coils in a fixed, predetermined relationship; U.S. Pat. No. 5,949,155 to Tamura et al, which discloses a shaver with adjacent inductive coils set in a fixed relationship; U.S. Pat. No. 5,952,814 to Van Lerberghe, which discloses an inductive charger for a telephone wherein the physical relationship between the primary and secondary coils is fixed; and U.S. Pat. No. 6,028,413 to Brockman, which discloses a charging device having a mechanical guide for ensuring precise, predetermined alignment between the inductive coils. The conventional practice of providing precise alignment between the primary and secondary coil has placed significant limitation on the overall design and adaptability of inductively powered devices. Further, in conventional inductive systems, the power supply circuit, which drives the primary coil, and the secondary circuit, which inductively receives power from the primary, are designed and carefully tuned to match with one another to maximize the efficiency of the inductive coupling. This too has placed significant limitations on the overall design and adaptability of inductively powered devices. | <SOH> SUMMARY OF THE INVENTION <EOH>The aforementioned problems are overcome by the present invention wherein an inductively powered device is provided with a mechanism for varying the relative position between the primary and the secondary to control the amount of power supplied to the load. In one embodiment, the present invention is incorporated into a dimmable lamp assembly in which a primary is mounted to the lamp base and the secondary is mounted to the lamp assembly. The brightness of the lamp is controlled by adjusting the distance between the lamp assembly and the lamp base. In a second embodiment, the present invention is incorporated into a dimmable lamp assembly in which the lamp brightness is controlled by varying the relative angular orientation of the primary and the secondary. In this embodiment, the primary is generally ring-shaped and the secondary is pivotally mounted within the ring. The lamp assembly includes a mechanical dimmer that rotates either the primary or the secondary so that their relative angular orientation varies. The variation in relative orientation varies the amount of power transferred to the secondary, thereby varying the brightness of the lamp. In another embodiment, the present invention is incorporated into a wind chime having one or more lamps that vary in brightness based on the movement of the chimes. In this embodiment, a plurality of chime assemblies is suspended within a primary coil, with each chime assembly being individually movable. Each chime assembly includes a secondary disposed at its upper end within the magnetic field of the primary. As the wind blows, the chime assemblies swing with respect to the primary, thereby varying the locations and orientation of the secondary coils within the magnetic field of the primary. This causes the brightness of the wind chimes to vary in respond to the wind. In yet another embodiment, the present invention provides an infinitely adjustable power supply for use with electrically powered devices where it is desirable to adjust the magnitude of power supplied to the device. The power supply includes an inductive coupling disposed between the power supply and the load. The inductive coupling includes a primary and a secondary. The infinitely adjustable power supply also includes an adjustment mechanism for selectively varying the relative position between the primary and the secondary, such as distance or angular orientation. The adjustment mechanism permits adjustment of the coupling coefficient and consequently the magnitude of power induced in the secondary and supplied to the load. In a second aspect, the present invention is directed to an inductive power supply station that is capable of providing power to a plurality of inductive powered devices placed at random location and at random orientations with respect to the primary. The inductive power supply station generally includes a single primary arranged about a receptacle that is capable of receiving randomly placed inductively powered devices. The power supply circuit includes circuitry for adjusting the power supplied to the primary as a function of the inductively powered devices present in the receptacle. In one embodiment, the receptacle is a dish, bowl or similar structure in which one or more lamp assemblies can be placed to provide light. Each lamp assembly includes a secondary that inductively receives power from the primary. The brightness of the light can be controlled by varying the number of lamp assemblies placed in the receptacle and by moving the lamp assemblies within the receptacle. In a third aspect, the present invention provides a secondary with a plurality of coils that are arranged at different orientations. The multiple coils permit the secondary to efficiently receive power when disposed at different orientations with respect to the primary. In one embodiment, a secondary with multiple coils is incorporated into an inductively powered lamp. The lamp assembly can receive maximum induced power when placed at different orientations within the magnetic field of the primary. In another embodiment, the lamp assembly includes a plurality of coils, each being electrically connected to a different light sources, for example, light sources of different colors. By adjusting the orientation of the lamp assembly, the color of emitted light can be varied by altering the respective brightness of the separate light sources. These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings. | 20050114 | 20080923 | 20050616 | 73146.0 | 0 | VU, DAVID HUNG | INDUCTIVELY POWERED APPARATUS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,036,727 | ACCEPTED | Magnetic resonance system and operating method for RF pulse optimization | In a magnetic resonance system and an operating method therefor, a B1 field distribution of a radio-frequency antenna is measured in at least one part of a examination volume of the magnetic resonance system, and then the RF pulses emitted by the radio-frequency antenna are optimized, based on the determined B1 field distribution, for homogenization in a specific volume. An effective volume within the examination volume is determined beforehand for each applied RF pulse and, based on the determined B1 field distribution, the appertaining RF pulse is individually adjusted such that the B1 field is homogenized within the effective volume of the RF pulse. | 1. A method for operating a magnetic resonance system, comprising the steps of: prior to acquiring diagnostic magnetic resonance data from an examination volume of a subject with a pulse sequence including a plurality of RF pulses emitted from an RF antenna, determining an effective volume within said examination volume for each of said RF pulses, and measuring a B1 field distribution of said RF antenna in said examination volume; and acquiring said magnetic resonance diagnostic data by applying said pulse sequence to said subject and, in said pulse sequence, optimizing each of said RF pulses within the effective volume thereof to homogenize said B1 field in said effective volume thereof. 2. A method as claimed in claim 1 wherein measuring said B1 field distribution has measurement parameters associated therewith, and wherein applying said pulse sequence to said subject has control parameters associated therewith for emitting the respective RF pulses in said pulse sequence, and wherein the step of determining said effective volume comprises automatically determining said effective volume for each of said RF pulses dependent on at least one of said measurement parameters and the respective control parameters for that RF pulse. 3. A method as claimed in claim 1 wherein at least one of said RF pulses is a slice-selective RF pulse, and comprising, for said slice-selective RF pulse, determining said effective volume to substantially correspond to the selected slice produced by said slice-selective RF pulse. 4. A method as claimed in claim 1 wherein said pulse sequence is designed to obtain said magnetic resonance data from a plurality of slices in said examination volume, and includes a preparation RF pulse, and comprising determining the effective volume for said preparation RF pulse based on a set union of said plurality of slices. 5. A method as claimed in claim 1 wherein said pulse sequence includes a regional preparation RF pulse effective in a region of the examination subject, and comprising determining said effective volume as being substantially equal to said region. 6. A method as claimed in claim 1 comprising, for each of said RF pulses, determining one optimization volume within the effective volume for that RF pulse, dependent on a predetermined region of interest, and optimizing each of said RF pulses to homogenize said B1 field within said optimization volume thereof. 7. A method as claimed in claim 1 wherein said radio frequency antenna comprises a plurality of antenna elements, and comprising emitting each of said RF pulses from said antenna elements by activating the respective antenna elements with a respective phase and a respective amplitude, and comprising optimizing said RF pulses by selectively adjusting the respective phase and the respective amplitude used to emit the respective RF pulse, to optimize said B1 field in said effective volume. 8. A method as claimed in claim 7 wherein the step of determining said B1 field distribution comprises separately determining a B1 field distribution for each of said antenna elements. 9. A method as claimed in claim 1 comprising, upon optimization of each of said RF pulses, storing optimized control parameters associated with the emission of said RF pulses that produce the optimization of the respective RF pulses, and operating said RF antenna with the stored control parameters, when applying said pulse sequence to said subject, to emit said optimized RF pulses. 10. A magnetic resonance system comprising: a magnetic resonance scanner adapted to interact with an examination subject to acquire diagnostic magnetic resonance data from the subject, said magnetic resonance scanner including an RF antenna that emits RF pulses exhibiting a B1 field distribution in an examination volume of the subject, and a measuring unit that measures said B1 field distribution; and a control unit connected to said magnetic resonance scanner for operating said magnetic resonance scanner with a pulse sequence, including a plurality of RF pulses emitted by said RF antenna, to acquire said diagnostic magnetic resonance data from said examination volume of the subject, said control unit, prior to initiating said pulse sequence, determining an effective volume within said examination volume for each of said RF pulses and, in said pulse sequence, optimizing each of said RF pulses within the effective volume thereof to homogenize said B1 field distribution in said effective volume thereof. 11. A magnetic resonance system as claimed in claim 10 comprising a user interface allowing a user to enter a designation of a region of interest within said examination volume, and wherein said control device, for each of said RF pulses, determines an optimization volume for that RF pulse within said effective volume thereof, dependent on said region of interest, and optimizes said RF pulses to homogenize said B1 field distribution within said optimization volume. 12. A magnetic resonance system as claimed in claim 10 wherein said radio frequency antenna comprises a plurality of antenna elements, and wherein said control unit operates the respective antenna elements with respective phases and respective amplitudes for each of said RF pulses to optimize said RF pulses to homogenize said B1 field distribution in the respective effective volumes thereof. 13. A computer program product loadable into a programmable control device of a magnetic resonance system, said magnetic resonance system having an RF antenna that emits RF pulses having a B1 field distribution associated therewith, said computer program causing said control unit to operate said magnetic resonance scanner to: prior to acquiring diagnostic magnetic resonance data from an examination volume of a subject with a pulse sequence including a plurality of said RF pulses, determine an effective volume within said examination volume for each of said RF pulses, and to measure the B1 field distribution in said examination volume; and to apply said pulse sequence to said subject to acquire said magnetic resonance diagnostic data from said examination volume and, in said pulse sequence, to optimize each of said RF pulses within the effective volume thereof to homogenize said B1 field distribution in said effective volume thereof. | BACKGROUND OF THE INVENTION 1. Field of the Invention The invention concerns a method for operation of a magnetic resonance system of the type wherein, in which a B1 field distribution of the radio-frequency pulses (“RF pulses”) radiated into an examination volume by a radio-frequency antenna of the magnetic resonance examination system is determined, and then the RF pulses emitted by the radio-frequency antenna are optimized, based on the determined B1 field distribution, for homogenization in a specific volume. Moreover, the invention concerns a magnetic resonance system of the type having a radio-frequency antenna for emission of RF pulses into an examination volume, with a measuring unit to measure a B1 field distribution of the RF pulses radiated into the examination volume by the radio-frequency antenna, and with a control device which, based on the determined B1 field distribution, optimizes the RF pulses emitted by the radio-frequency antenna for homogenization in a specific volume. 2. Description of the Prior Art Magnetic resonance tomography (MR tomography) has become a widespread technique for acquisition of images of the inside of the body of a living examination subject. In order to acquire an image with this modality, the body or body part of the patient is initially exposed to an optimally homogenous static basic magnetic field (generally designated as a B0 field) that is generated by a basic field magnet of the magnetic resonance measurement device. During the acquisition of the magnetic resonance images, rapidly switched gradient fields that are generated by gradient coils are superimposed on this basic magnetic field for spatial coding. Moreover, with a radio-frequency antenna, RF pulses of a defined field strength are radiated into the examination volume in which the examination subject is located. The pulse-shaped radio-frequency field is generated thereby generally called a B1 field. By means of these RF pulses, the nuclear spins of the atoms in the examination subject are excited such that they are moved from their state of equilibrium, which runs parallel to the basic magnetic field B0, by what is known as an “excitation flip angle (or “flip angle”). The nuclear spin then processes in the direction of the basic magnetic field B0. The magnetic resonance signals thereby generated are acquired by radio-frequency receiving antennas. The receiving antennas can be either the same antennas with which the RF pulses were radiated or separate receiving antennas. The magnetic resonance images of the examination subject are ultimately generated based on the received magnetic resonance signals. Every image point in the magnetic resonance image is associated with a small body volume, what is known as a “voxel’, and every brightness or intensity value of the image points is linked with the signal amplitude of the magnetic resonance signal received from this voxel. The association between a resonant radiated RF pulse with the field strength B1 and the flip angle α achieved therewith is given by the equation α = ∫ t = 0 τ γ · B 1 ( t ) · ⅆ t ( 1 ) wherein γ is the gyromagnetic ratio (which can be viewed as a fixed material constant for most of the nuclear magnetic resonance examinations) and τ is the effective duration of the RF pulse. The flip angle achieved by an emitted RF pulse, and thus the strength of the magnetic resonance signal, consequently depends on (aside from the duration of the RF pulse) the strength of the radiated B1 field. Spatial fluctuations in the field strength of the excited B1 field therefore lead to unwanted variations in the received magnetic resonance signal that can adulterate the measurement result. For high magnetic field strengths—that are inevitable given due necessary magnetic basic field B0 in a magnetic resonance tomography scanner—the RF pulses disadvantageously exhibit an inhomogeneous penetration behavior in conductive and dielectric media such as, for example, tissue. This leads to the B1 field significantly varying within the measurement volume. In particular in examinations known as ultra-intense field magnetic resonance examinations, in which modern magnetic resonance systems are used with a basic magnetic field of three Tesla or more, special measures must be taken in order to achieve an optimally homogenous distribution of the transmitted RF field of the radio-frequency antenna in the entire volume. In United States Application Publication 2003/0184293, the function and an application of a multi-channel transmission array is specified for this purpose. The radio-frequency signal emitted by a radio-frequency transmission amplifier is apportioned via an output splitter and a phase shifter among the individual segments of the array. In this document, however, it is only very generally mentioned that a field homogenization can be achieved with this technique. A further promising approach for this purpose is specified in German OS 101 24 465, corresponding to United States Application Publication 2004/0155656. In this document, a transmission and reception coil for MR apparatuses is specified that has a number of individual antenna elements (resonator segments) that are arranged around the examination volume within a gradient tube. These antenna elements are interconnected into a large-area volume antenna similar to what is known as a birdcage antenna. The individual antenna elements are electromagnetically decoupled from one another via interconnected capacitors. A separate transmission channel via which the radio frequency feed ensues is associated with each antenna element. Phase and amplitude thereby can be individually predetermined for each antenna element. In principle, this enables a complete control of the radio-frequency field distribution in the examination volume (known as “RF shimming”). It is proposed to improve the homogeneity of the RF field in the entire examination volume in this manner. Since, however, in a magnetic scan, every RF pulse acts in general in a different manner both with regard to its function and with regard to the relevant volumes, this optimization strategy is too restrictive. SUMMARY OF THE INVENTION An object of the present invention to provide a method for operation of a magnetic resonance system and a magnetic resonance system, with which a better optimization of the RF pulses with regard to the homogeneity of the B1 field can be achieved. This object is achieved by a method according to the invention wherein, for each applied RF pulse, an effective volume within the examination volume is determined beforehand and individually adjusted, based on the determined field distribution of the appertaining RF pulse, such that the B1 field is homogenized within the effective volume of the RF pulse. The best possible functionality of each applied RF pulse is thereby achieved. The consequence of this is an image quality optimized with regard to all radio-frequency-sensitive dependencies. For this purpose, the inventive magnetic resonance system must have a control device and a radio-frequency antenna that are fashioned such that, for each applied RF pulse, an effective volume within the examination volume can be determined beforehand and individually adjusted, based on the determined field distribution of the appertaining RF pulse, such that the B1 field is homogenized within the effective volume of the RF pulse. In order to individually optimize the “RF shim” for each individually applied RF pulse, such that an optical homogenization is achieved in the effective volume of the RF pulse, it is absolutely necessary to know the B1 distribution within the appertaining effective volume. This means that the B1 field distribution must be measured in the examination volume with spatial resolution. One possibility for implementation of such a measurement is known as a “double echo radio-frequency pulse sequence”, in which a first excitation pulse and two refocusing pulses for generation of a first echo and a second echo, is emitted via the radio-frequency antenna. This means that initially a first radio-frequency excitation pulse is emitted which tips the nuclear spins by, for example, a flip angle α1. After a specific time, a second pulse (known as a “refocusing pulse”) is emitted that leads to a further tipping by 2−α1. After measurement of a first echo (known as the spin echo), a further α1 refocusing pulse is then emitted and a second echo (known as the stimulated echo) is measured. For the amplitudes of the measured spin echo signal ASE and of the measured stimulated echo signal ASTE, the following dependencies on the flip angle α1 apply: ASE=eiφ sin3(α1) (2a) ASTE=eiφ sin3(α1)cos(α1) (2b) wherein φ designates the phase position of the echo signal. The flip angle α1 achieved with such a pulse sequence consequently can be determined from the ratio of the amplitudes of both echo signals by the relation cos α 1 = A STE A SE ( 3 ) This flip angle α1 can be converted into the radiated B1 field using equation (1). In order to be able to measure with spatial resolution, in this method at least the excitation pulse is slice-selectively radiated. Preferably only the excitation pulse but not the refocusing pulses is slice-selectively radiated. In the excitation slice established by means of the excitation pulse data for, a first echo image and a second echo image are then measured with spatial resolution via the radiation of the matching gradient pulses. Such a “spatially resolved” measurement of the echo images is possible with a method in which initially both echoes are measured by the application of a readout gradient by sampling the time curve with m data points multiple times with n different amplitudes of the phase coding gradient. The result of this measurement is then a data matrix with m columns and n rows for each of the echoes (i.e. the spin echo and the stimulated echo) in the time domain (also called “k-space”). This matrix is two-dimensionally Fourier-transformed for each echo. For each echo a real two-dimensional image with k pixels is thereby obtained, in general with m=n=k=1 being set. Using the ratio of the amplitudes of the first and second echo image at the various locations, i.e. for each individual image pixel, the local flip angles are then measured at the appertaining locations. By such a measurement, the flip angle, i.e. a flip angle distribution, can be measured with spatial resolution within the slice. The flip angle measured at a specific location is in turn representative for the B1 field radiated at the appertaining location, with the dependency given by equation (1). This means that, using this equation (given knowledge of the pulse used), it can be arbitrarily converted from a flip angle distribution into a B1 field distribution and vice versa. Thus herein a determination of a flip angle distribution is equated with a determination of the corresponding B1 field distribution. As an alternative to this technique, any other suitable method for spatially-resolved measurement of the B1 field distribution can be used. In principle, it is possible for a user to individually predetermine the effective volume for every pulse, for example via suitable functions of a user interface of the magnetic resonance system. However, for an RF pulse to be radiated, the effective volume preferably is automatically determined on the basis of the control parameters for radiation of the appertaining RF pulse. This means that the effective volume is automatically determined for the individual types of pulses in an “intelligent measurement sequence”. The system thereby recognizes, for example, whether slice-selective excitation and refocusing pulses are being used. This means that the slice in which the RF pulse acts in the examination volume is, for example, determined using the control parameters—for example, using the slice gradient to be set and the frequency of the RF pulse to be radiated. The measurement parameters coming directly from the user interface or from a planning program, which measurement parameters contain immediate information about the slice position and type of the acquisition, preferably can be used. The effective volume is then particularly suitably selected, substantially corresponding to the selected slice, for a slice-selective RF pulse to be radiated. The term “slice” as used herein encompasses a thicker slice of the type used for a 3D volume acquisition, known as a “slab”. The system can likewise automatically recognize whether a preparation pulse (for example a saturation pulse or magnetization transfer pulse) without spatial selectivity or with spatial selectivity (with or without spectral selectivity) is employed and, if so, in which region the preparation pulse should act. For a preparation pulse to be radiated without spatial selectivity, the effective volume is determined based on the set union of a specific number of slices, preferably based on the set union of all slices or slab volumes acquired in the examination. Fat saturation pulses lend themselves best to this, since fat saturation pulses generally are applied without spatial selectivity. For a preparation pulse acting only regionally, the effective volume preferably is selected such that it substantially corresponds to the appertaining region. In a preferred embodiment of the method, the user can additionally predetermine a region of interest to the user, for example the user can already set what is known as the “region of interest” in the planning. A optimization value is then respectively, automatically determined within the appertaining effective volume dependent on this region of interest. For example, the optimization volume can be established as a slice quantity from the (preferably automatically) determined effective volume and the region of interest predetermined by the user. The RF pulse is then individually adjusted such that the B1 field is optimally homogenous within the optimization volume. For this purpose, the magnetic resonance system must have a corresponding user interface for input of a region of interest within the examination volume, and the control unit must be fashioned in order to determine the optimization volume based on the region of interest within the effective volume, and then to individually adjust the RF pulses such that the B1 field is homogenized within the optimization volume. In order to achieve a corresponding homogenization of the RF pulses in the desired effective volume or optimization volume, the magnetic resonance system preferably has a radio-frequency antenna formed as an antenna arrangement with a number of antenna elements. Moreover, this magnetic resonance system has an activation unit in order to respectively activate the antenna elements with a specific phase and a specific amplitude for each RF pulse. One possibility for the design of such an antenna arrangement is described in German OS 101 24 465 (cited above), the teachings of which are incorporated herein by reference. Given the use of a radio-frequency antenna composed of multiple antenna elements, the B1 field distribution preferably is separately determined for each antenna element in order to determine the effect of that individual antenna element within the examination volume. This means that, for example, the “double-echo radio-frequency pulse sequence” cited above for spatially-resolved measurement of the B1 field is radiated by each individual antenna element in succession. Since the automatic calculation of the effective volume, and in particular also the calculation of the optimized control parameters for activation of the radio-frequency antenna, is relatively calculation-intensive and thus time-consuming, a complete calculation of the acquisition sequence preferably ensues beforehand for all optimized RF pulses to be radiated during the diagnostic data acquisition sequence. This means that all effective volumes and/or optimization volumes are determined in a planning cycle for the individual RF pulses, and the optimized control parameters, for example the individual phases and amplitudes for the various antenna elements, are calculated and stored in a measurement protocol. In the actual measurement, only the activation of the radio-frequency antenna then ensues according to the pre-calculated measurement protocol, with the matching amplitude and phase activation of the individual antenna elements being adjusted immediately prior to radiation of the RF pulse. The realization of the control device of the inventive magnetic resonance system preferably ensues using software components. Typical control devices of existing magnetic resonance systems normally include a programmable processor anyway, such that an upgrade of these magnetic resonance systems is possible in a simple manner with a corresponding software update. It is then only necessary for the magnetic resonance system have a suitable radio-frequency antenna, for example with a number of separately activatable antenna elements, in order to be able to arbitrarily influence the radiated B1 field of the individual RF pulses. DESCRIPTION OF THE DRAWINGS FIG. 1 schematically illustrates the establishment of an effective volume within a larger examination volume in an MR scan. FIG. 2a is the first part of a flow chart of an embodiment for automatic establishment of the effective volumes and the calculation of the optimized activation parameters for the radiation of optimized RF pulses in accordance with the invention. FIG. 2b is the second part of the flow chart of FIG. 2a. FIG. 3 schematically illustrates an exemplary sequence for a simple gradient echo experiment with three shown slices. FIG. 4 is a schematic illustration of an inventive magnetic resonance system. DESCRIPTION OF THE PREFERRED EMBODIMENTS A patient P lying on a patient bed 5 within an examination volume U of the magnetic resonance system is shown in FIG. 1. In the MR examination, exposures (scans) are generated in various slices S, S1, S2, S3 perpendicular to the longitudinal axis of the patient P. For clarity, here only three slices S1, S2, S3 are shown, significantly enlarged. The optimization of the radiated RF pulses inventively ensues, for each individual RF pulse, with regard to the slice in which the appertaining RF pulse should act. As an example, in FIG. 1 the slice S1 is determined as an effective volume W, with regard to which an optimal homogenization of the RF pulse radiated for excitation of the appertaining slice S1 should ensue. Additionally, in FIG. 1 the possibility of an operator of the MR system determining a “region of interest” ROI is schematically shown. In this case, the optimization of the RF pulse optionally ensues predominantly with regard to the slice quantity made up of effective volume W and region of interest ROI, i.e. in a limited sub-region of the effective volume W, the “optimization volume” O. A possible measurement workflow is shown in the flow chart in FIGS. 2a and 2b. Shown here is a method in which the effective volume is fully-automatically established—for example by the control device of the magnetic resonance system—dependent on the exposures to be produced. Such a measurement workflow begins with an adjustment measurement in which the B1 field distribution in the examination volume U of a radio-frequency antenna 3 is measured. In the present case, the radio-frequency antenna 3 has a number of individual antenna elements 4. In the adjustment measurement, the B1 field therefore is respectively, separately measured for all antenna elements 4 in order to determine the effect of the individual antenna elements 4 within the examination volume. This adjustment measurement ensues immediately prior to the actual measurement, whereby the patient is already located within the examination volume and the influences given by the special measurement arrangement are taken into account. An acquisition of overview images (what are known as “localizers”) that are used as orientation and planning images for the planning of the further measurement workflow subsequently ensues in a typical manner. In a third step, the measurement parameters for the examination are then established by the operator of the apparatus. This can ensue, for example, using the overview images with the aid of a graphical user interface. For example, the slices are determined, or it is established in which regional regions saturation slices are to be placed, etc. The actual calculation of the sequence workflow then ensues in the subsequent step. The shapes, the amplitudes and frequencies of the RF pulses necessary for the measurement i=1, . . . N are calculated, which RF pulses must be radiated in the course of the subsequent examination in order to implement the desired acquisitions. An automatic determination of the effective volume W(i) of the appertaining RF pulse subsequently ensues in a process loop for each individual RF pulse i=1, . . . , N, and a subsequent calculation of the optimized amplitude and phase activation parameters A(i,j), P(i,j) subsequently ensues for each individual antenna element in order to achieve overall an optimal “overall RF pulse” with optimally homogenous B1 field distribution in the determined effective volume W(i) by the superimposition of the RF pulses radiated by the individual antenna elements. The loop initially begins with an inquiry chain in order to establish whether, for example, it concerns a slice-selective pulse, a regional saturation pulse or a non-spatially-selective pulse. The steps represented here as individual inquiries alternatively can be formed of a number of individual query steps of various measurement parameters or control parameters, using which it can be established which type of pulse is concerned in which region of the examination volume the pulse should act. It is thus clear that a “normal” excitation pulse or refocusing pulse, for example, in a typical measurement pulse sequence is a slice-selective pulse. In this case, the established slice is recognized and established as a working volume W(i) using the set gradients and the selected frequency of the pulse. Likewise, given radiation of a regional saturation pulse, the effective volume W(i) can be set corresponding to the region in which the saturation pulse should act. If applicable, after further queries it is established that the pulse is not spatially selective at all. Thus, for example, it can be a general fat saturation pulse. In such cases, the entire imaging volume or, respectively, the entire examination volume is determined as an effective volume W(i) for the appertaining pulse. In a similar form, it can also be automatically tested whether it concerns a different regionally acting or non-regionally acting preparation pulse, however, for clarity this is not shown in FIG. 2b. After the determination of the effective volume W(i) for each individual RF pulse to be radiated, in the next step the optimal amplitude activation parameters A(i,j) and phase activation parameters P(i,j) for activation of each individual transmission element j=1, . . . , M are then determined for the appertaining pulse 1. FIG. 3 shows an exemplary sequence workflow for an emission of three successive RF pulses for three different slices S1, S2, S3. The RF pulses emitted in a typical manner on parallel time axes by the radio-frequency antenna—here by the individual antenna elements 1, . . . , M—and the matching switched, different gradients temporally dependent on the RF pulses are shown in this pulse frequency schema. The RF pulses emitted by the radio-frequency antenna elements j=1, 2, . . . , M are thereby respectively described by an amplitude modulation A(1), A(2), . . . , A(M) and a phase modulation P(1), P(2), . . . , P(M) shown directly on the axis beneath it, whereby the parameters specified in the parentheses specify the individual antenna elements j=1, 2, . . . , M. Under the axes for representation of the RF pulses emitted by the individual antenna elements j=1, 2, . . . , M, the slice selection gradient system is shown, which is applied in the z-direction and is used for the selection of a specific slice given excitation of the spins. Located below this is the phase coding gradient Gp, which provides for a phase coding. This phase coding gradient Gr is very rapidly switched to various values during a measurement. The third gradient Gr is the readout or frequency encoding gradient, which is applied in order to read out signals frequency-coded in a specific slice. The actual signal measured by the ADC (analog-digital converter) is shown on the lowermost time axis. Overall, a spatially-resolved measurement of signals within the slice determined by the slice-selection gradient together with the frequency of the excitation pulse ensues by suitable switching of the phase coding gradient Gp and the readout gradient Gr. The precise workflow of the phase coding and frequency coding for spatially-resolved measurement within a slice, as well as the representation in such a sequence schema, are known to those skilled in the art and therefore need not be explained further. The shown example concerns a simple gradient echo experiment with three shown slices S1, S2, S3. The selection of the slices S1, S2, S3 ensues as explained above, by the application of the selection gradients Gs and radiation of a radio-frequency pulse with respectively varying frequency. The different frequency of the RF pulses is shown here within the phase activation axes P(1), P(2), . . . , P(M) by a temporally linear phase response (which is, however, limited to +/−n). This means that, in a typical manner, the carrier frequency remains the same and the displacement of the radiated frequency of the excitation pulse ensues via the superimposition of the linear phase response. The frequency of the radio-frequency pulse can thus be shifted relative to the carrier frequency, dependent on the slope of the phase response. As can be seen in FIG. 3, the individual antenna elements j=1, 2, . . . , M are respectively activated with different amplitudes A(1), A(2), . . . , A(M) and phases P(1), P(2), . . . , P(M) for emission of the RF pulses for each of the three slices S1, S2, S3, in order to achieve overall an “overall RF pulse” with optimally good homogenization in the selected slice via the superimposition of all RF pulses emitted by the individual antenna elements j=1, 2, . . . , M. After the individual control parameters, i.e. the amplitude activation parameters and phase activation parameters for each transmission element j=1, . . . , M have been calculated for the appertaining pulse i, it is subsequently checked whether still further RF pulses must be optimized. For this, it is checked whether the control variable i has already achieved the value N of the number of the RF pulses to be emitted. If this is not the case, the control variable i is increased by 1 and the loop begins again from the start, i.e. for the next pulse (i+1) the effective volume W(i+1) is determined and the optimal amplitude and phase activation parameters are calculated for each antenna element. After these calculations for all pulses i=1, . . . , N have been implemented, in a later method step the measurement workflow is controlled in a typical manner, whereby the previously calculated amplitude and phase activation parameters A(i,j), P(i,j) is [sic] set for each individual antenna element j immediately prior to each RF pulse. In FIGS. 2a and 2b—for clarity—the case is not shown in which the user establishes the optimization volume, or in which the user establishes a region of interest ROI and the optimization volumes result as intersections from the region of interest ROI determined by the user and the automatically calculated effective volumes W(i) of the radio-frequency pulses. It is clear that it is possible without anything further to integrate these options in the planning, calculation and measurement process. FIG. 4 shows an exemplary embodiment of a magnetic resonance system 1 with which an automatic measurement according to the method shown in FIGS. 2a and 2b is possible. The core of this magnetic resonance system 1 is a scanner 2 in which a patient on a bed 5 is positioned in an annular basic field magnet. A radio-frequency antenna 3 for emission of the RF pulses is located within the basic field magnet. This radio-frequency antenna 3 has a number of antenna elements 4 that can be individually activated via separate transmission channels. The design can, for example, correspond to the design cited in German OS 101 24 465. Apart from the special design of the antenna 3 and the necessary components for separate activation of the individual antenna elements 4, it can be a standard tomography apparatus. The scanner 2 is operated by a control device 6, which is shown separately here. A terminal 14 is connected to the control device 6; this terminal 14 including, in a typical manner, a monitor 15, a keyboard 16 and a pointing device 17 for a graphical user interface, for example a mouse 17. The terminal 14 services as, among other things, a user interface via which an operator operates the control device 6 and therewith the scanner 2. The control device 6 is here connected with the scanner 2 via the interfaces 9, 10. Both the control device 6 and the terminal 14 can, however, likewise also be integral components of the scanner 2. The overall magnetic resonance system moreover also exhibits all further typical components or, respectively, features such as, for example, interfaces for connection to a communication network, for example an image information system. These components are not shown in FIG. 3 for clarity. Via the terminal 14, the operator can communicate with the activation unit 12, which activates the scanner 2 via the interface 9 and, for example, provides for an emission of the desired radio-frequency pulse sequences by the antennas 3 and switches the gradients in a suitable manner in order to implement the desired measurements. Via the interface 10, the measurement data coming from the scanner 2 is acquired and from this the images are reconstructed in a signal evaluation unit 13, which images then can be shown, for example, on the monitor 15 of the terminal 14 and/or be stored in a storage 8 of the control device 6. The activation unit 12 and the signal evaluation unit 13 can preferably be software modules which are realized on a programmable processor 7 of the control device 6. The storage 8 can also be an external mass storage to which the control device 6 has access, for example over a network. In the shown magnetic resonance system 1, the control device 6 moreover has a measuring unit 11 (likewise in the form of a software module) that serves for measurement of a B1 field distribution of the RF pulses radiated in the examination volume by the radio-frequency antenna 3 or by the individual antenna elements 4. For this, the measuring unit 11 prompts, for example, the activation unit 12 to transfer corresponding control commands to the tomograph 2, such that this emits the previously-described double-echo radio-frequency pulse sequences or similar sequences for measurement of the B1 field distribution. The raw data thereby measured are transferred from the signal evaluation unit 13 to the measuring unit 11. There, based on these data, the spatially-resolved B1 field distribution is determined for each individual antenna element 4. The information about the B1 field distribution is then transferred to an optimization unit—here again realized in the form of a software module—which determines, using the measurement parameters (predetermined by the user via the terminal 14 or automatically by the magnetic resonance system within a measurement protocol) for the RF pulses to be emitted in the following examination, the associated effective volumes or, respectively, optimization volumes and implements the optimization shown in FIG. 2b within the loop. This means that, in this optimization unit 18, the optimized amplitude activation parameter A(i,j) and the phase activation parameter P(i,j) are determined for the individual antenna elements 4 for each individual RF pulse. This information can then be initially buffered in the storage 8, for example in the form of an optimized measurement protocol. If the measurement is subsequently started, this measurement protocol with the optimized activation parameters is transferred from the storage 8 to the activation unit 12, and from there the scanner 2 is correspondingly activated in order to implement the optimized measurement. In conclusion, it is again noted that the method workflow specified in detail in the preceding as well as the shown magnetic resonance system are only exemplary embodiments which can be modified in the most varied manners by the average man skilled in the art without leaving the scope of the invention. In particular, instead of the described pulse sequence, other pulse sequences can be used. It is likewise also possible to design the antenna in another form other than that specified in German OS 101 24 465. It is significant that only one possibility is given to spatially adjust the B1 field distribution of the emitted radio-frequency pulses with optimal precision. Although the invention was previously described in an example of magnetic resonance apparatuses, the usage possibilities of the invention are not limited to this area; rather, the invention can likewise also be used in scientific and/or industrially-used magnetic resonance apparatuses. Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The invention concerns a method for operation of a magnetic resonance system of the type wherein, in which a B 1 field distribution of the radio-frequency pulses (“RF pulses”) radiated into an examination volume by a radio-frequency antenna of the magnetic resonance examination system is determined, and then the RF pulses emitted by the radio-frequency antenna are optimized, based on the determined B 1 field distribution, for homogenization in a specific volume. Moreover, the invention concerns a magnetic resonance system of the type having a radio-frequency antenna for emission of RF pulses into an examination volume, with a measuring unit to measure a B 1 field distribution of the RF pulses radiated into the examination volume by the radio-frequency antenna, and with a control device which, based on the determined B 1 field distribution, optimizes the RF pulses emitted by the radio-frequency antenna for homogenization in a specific volume. 2. Description of the Prior Art Magnetic resonance tomography (MR tomography) has become a widespread technique for acquisition of images of the inside of the body of a living examination subject. In order to acquire an image with this modality, the body or body part of the patient is initially exposed to an optimally homogenous static basic magnetic field (generally designated as a B 0 field) that is generated by a basic field magnet of the magnetic resonance measurement device. During the acquisition of the magnetic resonance images, rapidly switched gradient fields that are generated by gradient coils are superimposed on this basic magnetic field for spatial coding. Moreover, with a radio-frequency antenna, RF pulses of a defined field strength are radiated into the examination volume in which the examination subject is located. The pulse-shaped radio-frequency field is generated thereby generally called a B 1 field. By means of these RF pulses, the nuclear spins of the atoms in the examination subject are excited such that they are moved from their state of equilibrium, which runs parallel to the basic magnetic field B 0 , by what is known as an “excitation flip angle (or “flip angle”). The nuclear spin then processes in the direction of the basic magnetic field B 0 . The magnetic resonance signals thereby generated are acquired by radio-frequency receiving antennas. The receiving antennas can be either the same antennas with which the RF pulses were radiated or separate receiving antennas. The magnetic resonance images of the examination subject are ultimately generated based on the received magnetic resonance signals. Every image point in the magnetic resonance image is associated with a small body volume, what is known as a “voxel’, and every brightness or intensity value of the image points is linked with the signal amplitude of the magnetic resonance signal received from this voxel. The association between a resonant radiated RF pulse with the field strength B 1 and the flip angle α achieved therewith is given by the equation α = ∫ t = 0 τ γ · B 1 ( t ) · ⅆ t ( 1 ) wherein γ is the gyromagnetic ratio (which can be viewed as a fixed material constant for most of the nuclear magnetic resonance examinations) and τ is the effective duration of the RF pulse. The flip angle achieved by an emitted RF pulse, and thus the strength of the magnetic resonance signal, consequently depends on (aside from the duration of the RF pulse) the strength of the radiated B 1 field. Spatial fluctuations in the field strength of the excited B 1 field therefore lead to unwanted variations in the received magnetic resonance signal that can adulterate the measurement result. For high magnetic field strengths—that are inevitable given due necessary magnetic basic field B 0 in a magnetic resonance tomography scanner—the RF pulses disadvantageously exhibit an inhomogeneous penetration behavior in conductive and dielectric media such as, for example, tissue. This leads to the B 1 field significantly varying within the measurement volume. In particular in examinations known as ultra-intense field magnetic resonance examinations, in which modern magnetic resonance systems are used with a basic magnetic field of three Tesla or more, special measures must be taken in order to achieve an optimally homogenous distribution of the transmitted RF field of the radio-frequency antenna in the entire volume. In United States Application Publication 2003/0184293, the function and an application of a multi-channel transmission array is specified for this purpose. The radio-frequency signal emitted by a radio-frequency transmission amplifier is apportioned via an output splitter and a phase shifter among the individual segments of the array. In this document, however, it is only very generally mentioned that a field homogenization can be achieved with this technique. A further promising approach for this purpose is specified in German OS 101 24 465, corresponding to United States Application Publication 2004/0155656. In this document, a transmission and reception coil for MR apparatuses is specified that has a number of individual antenna elements (resonator segments) that are arranged around the examination volume within a gradient tube. These antenna elements are interconnected into a large-area volume antenna similar to what is known as a birdcage antenna. The individual antenna elements are electromagnetically decoupled from one another via interconnected capacitors. A separate transmission channel via which the radio frequency feed ensues is associated with each antenna element. Phase and amplitude thereby can be individually predetermined for each antenna element. In principle, this enables a complete control of the radio-frequency field distribution in the examination volume (known as “RF shimming”). It is proposed to improve the homogeneity of the RF field in the entire examination volume in this manner. Since, however, in a magnetic scan, every RF pulse acts in general in a different manner both with regard to its function and with regard to the relevant volumes, this optimization strategy is too restrictive. | <SOH> SUMMARY OF THE INVENTION <EOH>An object of the present invention to provide a method for operation of a magnetic resonance system and a magnetic resonance system, with which a better optimization of the RF pulses with regard to the homogeneity of the B 1 field can be achieved. This object is achieved by a method according to the invention wherein, for each applied RF pulse, an effective volume within the examination volume is determined beforehand and individually adjusted, based on the determined field distribution of the appertaining RF pulse, such that the B 1 field is homogenized within the effective volume of the RF pulse. The best possible functionality of each applied RF pulse is thereby achieved. The consequence of this is an image quality optimized with regard to all radio-frequency-sensitive dependencies. For this purpose, the inventive magnetic resonance system must have a control device and a radio-frequency antenna that are fashioned such that, for each applied RF pulse, an effective volume within the examination volume can be determined beforehand and individually adjusted, based on the determined field distribution of the appertaining RF pulse, such that the B 1 field is homogenized within the effective volume of the RF pulse. In order to individually optimize the “RF shim” for each individually applied RF pulse, such that an optical homogenization is achieved in the effective volume of the RF pulse, it is absolutely necessary to know the B 1 distribution within the appertaining effective volume. This means that the B 1 field distribution must be measured in the examination volume with spatial resolution. One possibility for implementation of such a measurement is known as a “double echo radio-frequency pulse sequence”, in which a first excitation pulse and two refocusing pulses for generation of a first echo and a second echo, is emitted via the radio-frequency antenna. This means that initially a first radio-frequency excitation pulse is emitted which tips the nuclear spins by, for example, a flip angle α 1 . After a specific time, a second pulse (known as a “refocusing pulse”) is emitted that leads to a further tipping by 2−α 1 . After measurement of a first echo (known as the spin echo), a further α 1 refocusing pulse is then emitted and a second echo (known as the stimulated echo) is measured. For the amplitudes of the measured spin echo signal ASE and of the measured stimulated echo signal A STE , the following dependencies on the flip angle α 1 apply: in-line-formulae description="In-line Formulae" end="lead"? A SE =e iφ sin 3 (α 1 ) (2a) in-line-formulae description="In-line Formulae" end="tail"? in-line-formulae description="In-line Formulae" end="lead"? A STE =e iφ sin 3 (α 1 )cos(α 1 ) (2b) in-line-formulae description="In-line Formulae" end="tail"? wherein φ designates the phase position of the echo signal. The flip angle α 1 achieved with such a pulse sequence consequently can be determined from the ratio of the amplitudes of both echo signals by the relation cos α 1 = A STE A SE ( 3 ) This flip angle α 1 can be converted into the radiated B 1 field using equation (1). In order to be able to measure with spatial resolution, in this method at least the excitation pulse is slice-selectively radiated. Preferably only the excitation pulse but not the refocusing pulses is slice-selectively radiated. In the excitation slice established by means of the excitation pulse data for, a first echo image and a second echo image are then measured with spatial resolution via the radiation of the matching gradient pulses. Such a “spatially resolved” measurement of the echo images is possible with a method in which initially both echoes are measured by the application of a readout gradient by sampling the time curve with m data points multiple times with n different amplitudes of the phase coding gradient. The result of this measurement is then a data matrix with m columns and n rows for each of the echoes (i.e. the spin echo and the stimulated echo) in the time domain (also called “k-space”). This matrix is two-dimensionally Fourier-transformed for each echo. For each echo a real two-dimensional image with k pixels is thereby obtained, in general with m=n=k=1 being set. Using the ratio of the amplitudes of the first and second echo image at the various locations, i.e. for each individual image pixel, the local flip angles are then measured at the appertaining locations. By such a measurement, the flip angle, i.e. a flip angle distribution, can be measured with spatial resolution within the slice. The flip angle measured at a specific location is in turn representative for the B 1 field radiated at the appertaining location, with the dependency given by equation (1). This means that, using this equation (given knowledge of the pulse used), it can be arbitrarily converted from a flip angle distribution into a B 1 field distribution and vice versa. Thus herein a determination of a flip angle distribution is equated with a determination of the corresponding B 1 field distribution. As an alternative to this technique, any other suitable method for spatially-resolved measurement of the B 1 field distribution can be used. In principle, it is possible for a user to individually predetermine the effective volume for every pulse, for example via suitable functions of a user interface of the magnetic resonance system. However, for an RF pulse to be radiated, the effective volume preferably is automatically determined on the basis of the control parameters for radiation of the appertaining RF pulse. This means that the effective volume is automatically determined for the individual types of pulses in an “intelligent measurement sequence”. The system thereby recognizes, for example, whether slice-selective excitation and refocusing pulses are being used. This means that the slice in which the RF pulse acts in the examination volume is, for example, determined using the control parameters—for example, using the slice gradient to be set and the frequency of the RF pulse to be radiated. The measurement parameters coming directly from the user interface or from a planning program, which measurement parameters contain immediate information about the slice position and type of the acquisition, preferably can be used. The effective volume is then particularly suitably selected, substantially corresponding to the selected slice, for a slice-selective RF pulse to be radiated. The term “slice” as used herein encompasses a thicker slice of the type used for a 3D volume acquisition, known as a “slab”. The system can likewise automatically recognize whether a preparation pulse (for example a saturation pulse or magnetization transfer pulse) without spatial selectivity or with spatial selectivity (with or without spectral selectivity) is employed and, if so, in which region the preparation pulse should act. For a preparation pulse to be radiated without spatial selectivity, the effective volume is determined based on the set union of a specific number of slices, preferably based on the set union of all slices or slab volumes acquired in the examination. Fat saturation pulses lend themselves best to this, since fat saturation pulses generally are applied without spatial selectivity. For a preparation pulse acting only regionally, the effective volume preferably is selected such that it substantially corresponds to the appertaining region. In a preferred embodiment of the method, the user can additionally predetermine a region of interest to the user, for example the user can already set what is known as the “region of interest” in the planning. A optimization value is then respectively, automatically determined within the appertaining effective volume dependent on this region of interest. For example, the optimization volume can be established as a slice quantity from the (preferably automatically) determined effective volume and the region of interest predetermined by the user. The RF pulse is then individually adjusted such that the B 1 field is optimally homogenous within the optimization volume. For this purpose, the magnetic resonance system must have a corresponding user interface for input of a region of interest within the examination volume, and the control unit must be fashioned in order to determine the optimization volume based on the region of interest within the effective volume, and then to individually adjust the RF pulses such that the B 1 field is homogenized within the optimization volume. In order to achieve a corresponding homogenization of the RF pulses in the desired effective volume or optimization volume, the magnetic resonance system preferably has a radio-frequency antenna formed as an antenna arrangement with a number of antenna elements. Moreover, this magnetic resonance system has an activation unit in order to respectively activate the antenna elements with a specific phase and a specific amplitude for each RF pulse. One possibility for the design of such an antenna arrangement is described in German OS 101 24 465 (cited above), the teachings of which are incorporated herein by reference. Given the use of a radio-frequency antenna composed of multiple antenna elements, the B 1 field distribution preferably is separately determined for each antenna element in order to determine the effect of that individual antenna element within the examination volume. This means that, for example, the “double-echo radio-frequency pulse sequence” cited above for spatially-resolved measurement of the B 1 field is radiated by each individual antenna element in succession. Since the automatic calculation of the effective volume, and in particular also the calculation of the optimized control parameters for activation of the radio-frequency antenna, is relatively calculation-intensive and thus time-consuming, a complete calculation of the acquisition sequence preferably ensues beforehand for all optimized RF pulses to be radiated during the diagnostic data acquisition sequence. This means that all effective volumes and/or optimization volumes are determined in a planning cycle for the individual RF pulses, and the optimized control parameters, for example the individual phases and amplitudes for the various antenna elements, are calculated and stored in a measurement protocol. In the actual measurement, only the activation of the radio-frequency antenna then ensues according to the pre-calculated measurement protocol, with the matching amplitude and phase activation of the individual antenna elements being adjusted immediately prior to radiation of the RF pulse. The realization of the control device of the inventive magnetic resonance system preferably ensues using software components. Typical control devices of existing magnetic resonance systems normally include a programmable processor anyway, such that an upgrade of these magnetic resonance systems is possible in a simple manner with a corresponding software update. It is then only necessary for the magnetic resonance system have a suitable radio-frequency antenna, for example with a number of separately activatable antenna elements, in order to be able to arbitrarily influence the radiated B 1 field of the individual RF pulses. | 20050114 | 20070515 | 20050901 | 66605.0 | 0 | FETZNER, TIFFANY A | MAGNETIC RESONANCE SYSTEM AND OPERATING METHOD FOR RF PULSE OPTIMIZATION | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,036,837 | ACCEPTED | Smart lock-in circuit for phase-locked loops | The smart lock-in circuits basically include a sensor, two stacked PMOS transistors, two stacked NMOS transistors, and a feedback line. If the sensing voltage does not reach the expected voltage compared to the midpoint voltage of the sensor, the output voltage of the sensor turns on the corresponding transistor, which provides a current to its output until the voltage at feedback reaches the midpoint voltage. The time to reach the midpoint voltage at a filter is simply equal to the charge stored at the filter divided by the current, which can be scaled by a device aspect ratio of the transistor. Consequently, all smart lock-in circuits provide an initial loop condition closer to the expected loop condition according to schedule. | 1. A smart lock-in circuit for enabling any phase-locked loop to become locked according to schedule, comprising: a feedback line connected with the output and input of the smart lock-in circuit and also coupled to the output of a filter; a sensor for sensing a voltage at the output, comparing with the midpoint voltage of the sensor, and providing its output; two stacked PMOS transistors connected between power supply and the output; and two stacked NMOS transistors connected between the output and ground. 2. The circuit as recited in claim 1 wherein the sensor is a low-voltage sensor. 3. The circuit as recited in claim 2 wherein the low-voltage sensor's output is coupled to the gate terminal of the upper PMOS transistor. 4. The circuit as recited in claim 1 wherein the sensor is a high-voltage sensor. 5. The circuit as recited in claim 4 wherein the high-voltage sensor's output is coupled to the gate terminal of the lower NMOS transistor. 6. The circuit as recited in claim 1 wherein the sensor is both a low-voltage sensor and a high-voltage sensor. 7. The circuit as recited in claim 6 wherein the low-voltage sensor's output is coupled to the gate terminal of the upper PMOS transistor and the high-voltage sensor's output is coupled to the gate terminal of the lower NMOS transistor. 8. The circuit as recited in claim 1 wherein the sensor is an even number of inverters 9. The circuit as recited in claim 1 wherein the sensor is comparator. 10. The circuit as recited in claim 1 wherein the sensor is operational amplifier. 11. The circuit as recited in claim 1 wherein the sensor is an even number of NAND gates since the two-input CMOS NAND gate can be used as an enabling inverter with one input serving as an active high enable input and the other used as the logical input. 12. The circuit as recited in claim 1 wherein the sensor is an even number of NOR gates since the two-input CMOS NOR gate can be used as an enabling inverter with one input serving as an active low enable input and the other used as the logical input. 13. The circuit as recited in claim 1 further comprising a power-down NMOS transistor so that no current flows into the circuit during power-down mode. 14. The circuit as recited in claim 13 wherein the output of the smart lock-in circuit is coupled to the output of the filter connected between the output and ground. 15. The circuit as recited in claim 13 wherein the output of the smart lock-in circuit is at ground when the power-down input is at the power supply. 16. The circuit as recited in claim 1 further comprising a power-down PMOS transistor and a power-down inverter so that no current flows into the circuit during power-down mode. 17. The circuit as recited in claim 16 wherein the output of the smart lock-in circuit is coupled to the output of the filter connected between the output and power supply. 18. The circuit as recited in claim 16 wherein the output of the smart lock-in circuit is at power supply when the power-down input is at the power supply. 19. The circuit as recited in claim 16 wherein a power-down inverter is an odd number of inverters. 20. The circuit as recited in claim 1 wherein the smart lock-in circuit is applied to all phase-locked loops without regard to architectures, topologies, and schematics. | FIELD OF THE INVENTION The present invention relates to the field of fast-locking phase-locked loops and more particularly to smart lock-in circuit for phase-locked loops. BACKGROUND ART Phase-looked loop is a vitally important device. Phase-looked loop is analog and mixed signal building block used extensively in communication, networks, digital systems, consumer electronics, computers, and any other fields that require frequency synthesizing, clock recovery, and synchronization. Prior Art FIG. 1 illustrates a block diagram of a basic architecture of two types of conventional phase-locked loops, which are a conventional phase-locked loop 110 and a conventional fast-locking phase-locked loop 120. The conventional phase-locked loop 110 typically consists of a phase-frequency detector (or phase detector), a charge-pump, a low-pass filter, and a voltage-controlled oscillator in a loop. Phase-locked loops without any frequency divider in a loop are considered here for simplicity. The phase-frequency detector (or phase detector) is a block that has an output voltage with an average value proportional to the phase difference between the input signal and the output signal of the voltage-controlled oscillator. The charge-pump either injects the charge into the low-pass filter or subtracts the charge from the low-pass filter, depending on the outputs of the phase-frequency detector (or phase detector). Therefore, change in the low-pass filter's output voltage drives the voltage-controlled oscillator. The negative feedback of the loop results in the output of the voltage-controlled oscillator being synchronized with the input signal. As a result, the phase-locked loop is in lock. In the conventional phase-locked loop 110 of Prior Art FIG. 1, lock-in time is defined as the time that is required to attain lock from an initial loop condition. Assuming that the phase-locked loop bandwidth is fixed, the lock-in time is proportional to the difference between the input signal frequency and the initial voltage-controlled oscillator's frequency as follows: ( ω in - ω osc ) 2 ω 0 3 where ωin is the input signal frequency, ωasc is the initial voltage-controlled oscillator's frequency, and ω0 is the loop bandwidth. The loop bandwidth must be wide enough to obtain a fast lock-in time. But most systems require a fast lock-in time without regard to the input signal frequency, bandwidth, and output phase jitter due to external noise. However, the conventional phase-locked loop 110 shown in Prior Art FIG. 1 has suffered from slow locking and harmonic locking. Thus, time and power are unnecessarily consumed until the phase-locked loops become locked. In addition, it has taken a vast amount of time to simulate and verify the conventional phase-locked loop 110 before fabrication since the simulation time of phase-locked loop circuits is absolutely proportional to time that is required the phase-locked loops to be locked. This long simulation adds additional cost and serious bottleneck to better design time to market. For these reasons, the conventional phase-locked locked loop 110 of Prior Art FIG. 1 is very inefficient to implement in an integrated circuit (IC) or system-on-chip (SOC). To overcome the drawbacks of the conventional phase-locked loop 110 of Prior Art FIG. 1, a conventional fast-locking phase-locked loop 120 of Prior Art FIG. 1 is illustrated. The conventional fast-locking phase-locked loop 120 consists of a digital phase-frequency detector, a proportional-integral controller 122, a 10-bit digital-to-analog converter 124, and a voltage-controlled oscillator. Unfortunately, the conventional fast-locking phase-locked loop is costly, complicated, and inefficient to implement in system-on-chip (SOC) or integrated circuit (IC) because additional proportional-integral controller 122 and the 10-bit digital-to-analog converter 124 take much more chip area, consume much more power, and make the stability analysis very difficult. The complexity increases the number of blocks that need to be designed and verified. The conventional fast-locking phase-locked loop 120 might improve the lock-in time, but definitely results in bad time-to-market, higher cost, larger chip area, much more power consumption, and longer design time. Thus, what is desperately needed is a highly cost-effective fast-locking phase-locked loop that can be highly efficiently implemented with a drastic improvement in a very fast lock-in time, lock-in time controllability, performance, cost, chip area, power consumption, stand-by time, and fast design time for much better time-to-market. At the same time, serious harmonic locking problem has to be resolved. The present invention satisfies these needs by providing smart lock-in circuits. SUMMARY OF THE INVENTION The present invention provides five types of the smart lock-in circuits for phase-locked loops. The smart lock-in circuits simultaneously enable any phase-locked loop to be locked according to schedule. The basic architecture of the smart lock-in circuits consists of a sensor, two stacked PMOS transistors, two stacked NMOS transistors, and a feedback line. The sensor senses a voltage at its input. If the sensing voltage does not reach the expected voltage compared to the midpoint voltage of the sensor, the output voltage of the sensor turns on the corresponding transistor, which provides a current to its output until the output voltage reaches the midpoint voltage. The time to reach the midpoint voltage at the filter is simply equal to the charge stored at the filter divided by the current, which can be scaled. Consequently, all smart lock-in circuits provide a significant reduction in the difference between the initial loop condition and the locked condition in order to overcome serious drawbacks simultaneously. The lock-in time controllability enables all of the phase-locked loops on the chip to be locked according to schedule. In addition, the present invention has five different embodiments which achieve a drastic improvement in a very fast lock-in time, lock-in time controllability, performance, cost, chip area, power consumption, stand-by time, and design time. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and form a part of this specification, illustrate five embodiments of the invention and, together with the description, serve to explain the principles of the invention: Prior Art FIG. 1 illustrates a block diagram of two types of conventional phase-locked loops. FIG. 2 illustrates a block diagram of two types of smart lock-in circuits for phase-locked loops in accordance with the present invention. FIG. 3 illustrates a circuit diagram of a basic smart lock-in circuit according to the present invention. FIG. 4 illustrates a circuit diagram of a smart lock-in circuit in accordance with the present invention. FIG. 5 illustrates a circuit diagram of a dual smart lock-in circuit according to the present invention. FIG. 6 illustrates a circuit diagram of a p-type smart lock-in circuit in accordance with the present invention. FIG. 7 illustrates a circuit diagram of a p-type dual smart lock-in circuit according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following detailed description of the present invention, five types of the smart lock-in circuits, numerous specific details are set forth in order to provide a through understanding of the present invention. However, it will be obvious to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, CMOS digital gates, components, and metal-oxide-semiconductor field-effect transistor (MOSFET) device physics have not been described in detail so as not to unnecessarily obscure aspects of the present invention. FIG. 2 illustrates a block diagram of two types of the smart lock-in circuits for phase-locked loops in accordance with the present invention. One type of the smart lock-in circuit is applied for phase-locked loops including a filter 216 connected between VC and ground, as seen in the phase-locked loop 210 shown in FIG. 2. The other type of the smart lock-in circuit called “p-type smart lock-in circuit” is applied for phase-locked loops including a filter 226 connected between VDD and VC, as seen in the phase-locked loop 220 shown in FIG. 2. To reduce the difference between the initial loop condition and the locked condition, the outputs of the smart lock-in circuit 214 and the p-type smart lock-in circuit 224 are coupled to the outputs of the filter 216 and the filter 226, respectively, as shown in FIG. 2. The phase-locked loop 210 excluding the smart lock-in circuit 214 represents all types of phase-locked loops including a filter 216 connected between VC and ground without regard to the types of phase-locked loops because the applications of the smart lock-in circuit 214 is independent of architectures and types of phase-locked loops. The phase-locked loop 220 excluding the p-type smart lock-in circuit 224 represents all types of phase-locked loops including a filter 226 connected between VDD and VC without regard to the types of phase-locked loops because the applications of the p-type smart lock-in circuit 224 is independent of architectures and types of phase-locked loops. The filters 216 and 226 are low-pass filters. If these filters are multiple-order low-pass filters, then they will be approximated to the first-order filter with neglecting resistor in the filter for simplicity. FIG. 3 illustrates a basic smart lock-in circuit according to the present invention. This basic smart lock-in circuit 300 does not have power-down mode in order to show the fundamental concept of the invention clearly. The basic smart lock-in circuit 300 is a feedback circuit that consists of lower-voltage sensing inverters 302 and 312 (i.e., an even number of inverters), higher-voltage sensing inverters 304 and 324 (i.e., an even number of inverters), two stacked PMOS transistors 306 and 308, two stacked NMOS transistors 326 and 328, and a feedback line 310. The gate terminal of a PMOS transistor 308 is connected to a proper fixed-bias voltage (not shown) or ground (e.g., “0”, low, etc.). The gate terminal of a NMOS transistor 326 is connected to a proper fixed-bias voltage (not shown) or power supply voltage (e.g., VDD, “1”, high, etc.). It is assumed that the output of the basic smart lock-in circuit 300 is at ground. Since the first lower-voltage sensing inverter 302 initially senses a voltage less than the lower midpoint voltage of the first lower-voltage sensing inverter 302, the output voltage of the second lower-voltage sensing inverter 312 is low enough to turn on the PMOS transistor 306. At the same time, the output voltage of the second higher-voltage sensing inverter 324 is low enough to turn off the NMOS transistor 328. Thus, the PMOS transistor 306 provides a current (i.e., IP) to the output until the output voltage (i.e., VC) goes up to the lower midpoint voltage of the first lower-voltage sensing inverter 302. The time to reach the lower midpoint voltage at the filter connected between VC and ground is as follows: Δ t = V M C P I P where VM is the lower midpoint voltage determined by the device aspect ratios of the first lower-voltage sensing inverter 302 and CP is the value of the capacitor in the filter. Thus, the lock-in time of the phase-locked loops including the filter connected between VC and ground is approximately given by ( ω in - ω M ) 2 ω 0 3 + V M C P I P where ωin is the input signal frequency, ωM is the voltage-controlled oscillator's frequency for VC=VM, and ω0 is the loop bandwidth. This lock-in time is varied by the current IP depending on the size of the PMOS transistor 306. It is assumed that the output of the basic smart lock-in circuit 300 is at power supply. Since the first higher-voltage sensing inverter 304 initially senses a voltage greater than the higher midpoint voltage of the first higher-voltage sensing inverter 304, the output voltage of the second higher-voltage sensing inverter 324 is high enough to turn on the NMOS transistor 328. At the same time, the output voltage of the second lower-voltage sensing inverter 312 is high enough to turn off the PMOS transistor 306. Thus, the NMOS transistor 328 provides a current (i.e., IN) to the output until the output voltage (i.e., VC) goes down to the higher midpoint voltage of the first higher-voltage sensing inverter 304. The time to reach the higher midpoint voltage at the filter connected between VC and power supply is as follows: Δ t = ( V DD - V M ( H ) ) C P I N where VM(H) is the higher midpoint voltage determined by the device aspect ratios of the first higher-voltage sensing inverter 304 and CP is the value of the capacitor in the filter. Thus, the lock-in time of the phase-locked loops including the filter connected between VC and power supply is approximately given by ( ω in - ω M ( H ) ) 2 ω 0 3 + ( V DD - V M ( H ) ) C P I N where ωin is the input signal frequency, ωM(H) is the voltage-controlled oscillator's frequency for VC=VM(H), and ω0 is the loop bandwidth. This lock-in time is varied by the current IN depending on the size of the NMOS transistor 328. The midpoint voltage is a voltage where the input voltage and the output voltage of the inverter are equal in the voltage transfer characteristic. At the midpoint voltage, the transistors of the inverter operate in the saturation mode. This midpoint voltage of inverter is expressed as V DD - V T n - V T p 1 + K n K p + V T n where K n K p = μ n C OX ( W L ) n μ p C OX ( W L ) p In design of the basic smart lock-in circuit of FIG. 3, it is also desirable to use a value for the lower midpoint voltage, VM, less than VC′ and a value for the higher midpoint voltage, VM(H), greater than VC′. VC′ is the voltage that makes the frequency of the voltage-controlled oscillator equal to the input signal's frequency. FIG. 4 illustrates a smart lock-in circuit 400 according to the present invention. A power-down input voltage, VPD, is defined as the input voltage for power-down mode. The power-down enable system is in power-down mode when VPD is VDD and it is in normal mode when VPD is zero. The smart lock-in circuit 400 is a feedback circuit that consists of lower-voltage sensing inverters 402 and 412 (i.e., an even number of inverters), two stacked PMOS transistors 406 and 408, two stacked NMOS transistors 426 and 428, a feedback line 410, and a power-down NMOS transistor 442. In addition, the gate terminal of a PMOS transistor 408 is connected to a proper fixed-bias voltage (not shown) or ground (e.g., “0”, low, etc.). The gate terminal of a NMOS transistor 426 is connected to a proper fixed-bias voltage (not shown) or power supply voltage (e.g., VDD, “1”, high, etc.). Furthermore, the gate terminal of a NMOS transistor 428 is shorted and thus no current flows into the drains of the NMOS transistors 426 and 428. The circuit mode changes from power-down mode to normal mode in FIG. 4. Since the first lower-voltage sensing inverter 402 initially senses a voltage less than the lower midpoint voltage of the first lower-voltage sensing inverter 402, the output voltage of the second lower-voltage sensing inverter 412 is low enough to turn on the PMOS transistor 406. The PMOS transistor 406 generates a current (i.e., IP) to the output until the output voltage (i.e., VC) goes up to the lower midpoint voltage of the first lower-voltage sensing inverter 402. Furthermore, the lock-in time of the phase-locked loops including the filter connected between VC and ground is approximately given by ( ω in - ω M ) 2 ω 0 3 + V M C P I P where ωin is the input signal frequency, ωM is the voltage-controlled oscillator's frequency for VC=VM, and ω0 is the loop bandwidth. Also, VM is the lower midpoint voltage determined by the device aspect ratios of the first lower-voltage sensing inverter 402 and CP is the value of the capacitor in the filter. The lock-in time is varied by the current IP depending on the size of the PMOS transistor 406. In design of the smart lock-in circuit of FIG. 4, it is also desirable to use a value for the lower midpoint voltage, VM, less than VC′. VC′ is the voltage that makes the frequency of the voltage-controlled oscillator equal to the input signal's frequency. The smart lock-in circuit 400 is used for all types of phase-locked loops including the filter connected between VC and ground. Since the power-down NMOS transistor 442 is on during power-down mode, it provides an output pull-down path to ground. Thus, VC of the smart lock-in circuit 400 is zero so that no current flows into the circuits during power-down mode. FIG. 5 illustrates a dual smart lock-in circuit 500 in accordance with the present invention. The dual smart lock-in circuit 500 is a modification of the circuit described in FIG. 4. The gate terminal of a PMOS transistor 508 is connected to a proper fixed-bias voltage (not shown) or ground (e.g., “0”, low, etc.). The gate terminal of a NMOS transistor 526 is connected to a proper fixed-bias voltage (not shown) or power supply voltage (e.g., VDD, “1”, high, etc.). Furthermore, compared to FIG. 4, the first difference to note is that the higher-voltage sensing inverters 504 and 524 (i.e., an even number of inverters) are added into FIG. 5 in order to provide the higher-voltage sensing function. The second difference to note is that the output of the second higher-voltage sensing inverter 524 is connected to the gate terminal of a NMOS transistor 528. Therefore, the dual smart lock-in circuit 500 is able to sense the lower-voltage as well as the higher-voltage while the smart lock-in circuit 400 is able to sense only the lower-voltage. No current flows into the drains of the NMOS transistors 526 and 528 assuming VC<VM(H) where VM(H) is the higher midpoint voltage decided by the device aspect ratios of the first higher-voltage sensing inverter 504. If VC is greater than VM(H), the gate voltage of the NMOS transistor 528 is VDD. As a result, a current flows into the drains of the NMOS transistors 526 and 528 until VC goes down to VM(H). In design of the dual smart lock-in circuit of FIG. 5, it is also desirable to use a value for the midpoint voltage, VM, less than VC and a value for the higher midpoint voltage, VM(H), greater than V′C. V′C is the voltage that makes the frequency of the voltage-controlled oscillator equal to the input signal's frequency. VM is the midpoint voltage decided by the device aspect ratios of the first lower-voltage sensing inverter 502. The dual smart lock-in circuit 500 is used for all types of phase-locked loops including the filter connected between VC and ground. Zero dc volt at VC ensures that no current flows into the circuits during power-down mode. FIG. 6 illustrates a p-type smart lock-in circuit 600 according to the present invention. The power-down input voltage, VPD, is defined as the input voltage for the p-type power-down mode as well as for the power-down mode. The p-type power-down enable system is in power-down mode when VPD is VDD and it is in normal mode when VPD is zero. The p-type smart lock-in circuit 600 is a feedback circuit that consists of a higher-voltage sensing inverters 604 and 624 (i.e., an even number of inverters), two stacked PMOS transistors 606 and 608, two stacked NMOS transistors 626 and 628, a feedback line 610, a power-down inverter 614, and a power-down PMOS transistor 642. In addition, the gate terminal of a PMOS transistor 608 is connected to a proper fixed-bias voltage (not shown) or ground (e.g., “0”, low, etc.). The gate terminal of a NMOS transistor 626 is connected to a proper fixed-bias voltage (not shown) or power supply voltage (e.g., VDD, “1”, high, etc.). Furthermore, since the PMOS transistor 606 is turned off, no current flows out of the drains of the PMOS transistors 606 and 608. Also, VM(H) is the higher midpoint voltage decided by the device aspect ratios of the first higher-voltage sensing inverter 604. The circuit mode changes from p-type power-down mode to normal mode in FIG. 6. Since the first higher-voltage sensing inverter 604 initially senses a voltage greater than VM(H), the output voltage of the second higher-voltage sensing inverter 624 is high enough to turn on the NMOS transistor 628. The NMOS transistor 628 generates a current (i.e., IN) to the output until the output voltage, VC, goes down to VM(H). Thus, the lock-in time of the phase-locked loops including the filter connected between VC and power supply is approximately given by ( ω in - ω M ( H ) ) 2 ω 0 3 + ( V DD - V M ( H ) ) C P I N where ωin is the input signal frequency, ωM(H) is the voltage-controlled oscillator's frequency for VC=VM(H), and ω0 is the loop bandwidth. Also, CP is the value of the capacitor in the filter and VM(H)is the higher midpoint voltage determined by the device aspect ratios of the first higher-voltage sensing inverter 604. The lock-in time is varied by the current IN depending on the size of the NMOS transistor 628. In design of the p-type smart lock-in circuit of FIG. 6, it is also desirable to use a value for the higher midpoint voltage, VM(H), greater than VC′. VC′ is the voltage that makes the frequency of the voltage-controlled oscillator equal to the input signal's frequency. The p-type smart lock-in circuit 600 is used for all types of phase-locked loops including the filter connected between VC and power supply. The output voltage of the power-down inverter 614, VPDB, is zero during power-down mode. As a result, the power-down PMOS transistor 642 is turned on and thus provides an output pull-up path to VDD. Therefore, VC of the p-type smart lock-in circuit 600 is VDD so that no current flows into the circuits during power-down mode. On the contrary, it was stated earlier that VC must be zero when power-down mode occurs in FIG. 4 and FIG. 5. FIG. 7 illustrates a p-type dual smart lock-in circuit 700 in accordance with the present invention. The p-type dual smart lock-in circuit 700 is a modification of the circuit described in FIG. 6. The gate terminal of a PMOS transistor 708 is connected to a proper fixed-bias voltage (not shown) or ground (e.g., “0”, low, etc.). The gate terminal of a NMOS transistor 726 is connected to a proper fixed-bias voltage (not shown) or power supply voltage (e.g., VDD, “1”, high, etc.). Compared to FIG. 6, the first difference to note here is that the lower-voltage sensing inverters 702 and 712 (i.e., an even number of inverters) are added into FIG. 7 in order to sense the lower-voltage. The second difference to note here is that the output of the second lower-voltage sensing inverter 712 is connected to the gate terminal of the PMOS transistor 706. The p-type dual smart lock-in circuit 700 is able to sense the lower-voltage as well as the higher voltage while the p-type smart lock-in circuit 600 is able to sense only the higher voltage. No current flows out of the drains of the PMOS transistors 706 and 708 if VC is greater than VM. VM is the lower midpoint voltage decided by the device aspect ratios of the first lower-voltage sensing inverter 702. If VC is less than VM, the PMOS transistor 706 is turned on until VC goes up to VM. In design of the p-type dual smart lock-in circuit of FIG. 7, it is also desirable to use a value for the higher midpoint voltage, VM(H), greater than V′C and a value for the lower midpoint voltage, VM, less than V′C. V′C is the voltage that makes the frequency of the voltage-controlled oscillator equal to the input signal's frequency. The p-type dual smart lock-in circuit 700 is used for all types of phase-locked loops including the filter connected between VC and power supply. VC=VDD in the p-type dual smart lock-in circuit 700 ensures that no current flows into the circuits during power-down mode. In summary, the five smart lock-in circuits of the present invention simply control how fast the phase-locked loops become locked from an initial condition. Also, they provide a solution for harmonic locking problem. Furthermore, three smart lock-in circuits 300, 500, and 700 are highly effective for LC oscillator which has a very narrow tuning range. The balance between PMOS output resistance and NMOS output resistance is important to obtain high output resistance. Furthermore, the CMOS process variations usually must be considered so that the proper value of the midpoint voltage is chosen for all the smart lock-in circuits 300, 400, 500, 600, and 700. Each bulk of two stacked PMOS transistors can be connected to its own N-well to obtain better immunity from substrate noise in all smart lock-in circuits 300, 400, 500, 600, and 700. The smart lock-in circuit 214 shown in FIG. 2 represents the basic smart lock-in circuit 300, the smart lock-in circuit 400, and the dual smart lock-in circuit 500, as shown in FIG. 3, FIG. 4, and FIG. 5, respectively. Also, the p-type smart lock-in circuit 224 shown in FIG. 2 represents the basic smart lock-in circuit 300, the p-type smart lock-in circuit 600 and the p-type dual smart lock-in circuit 700, as shown in FIG. 3, FIG. 6, and FIG. 7, respectively. It is noted that SPICE is used for the simulation of phase-locked loops. The conventional phase-locked loop 110 and the phase-locked loop 210 including the basic smart lock-in circuit 300 of the invention are simulated using the same components. As a result, the total simulation time of the conventional phase-locked loop 110 is 20 hours and that of the phase-locked loop 210 is 1.9 hours. This improvement can be accomplished by simply inserting a proper one of the five smart lock-in circuits into any conventional phase-locked loop, and the simulation time can be reduced by a factor of 10. So far, it should be noted that the same time step has been used for the SPICE simulation in order to accurately measure and compare the simulation time of all circuits. All the smart lock-in circuits of the present invention are very efficient to implement in system-on-chip (SOC) or integrated circuit (IC). The present invention provides five different embodiments which achieve a drastic improvement in a very fast lock-in time, lock-in time controllability, performance, time-to-market, power consumption, stand-by time, cost, chip area, and design time. While the present invention has been described in particular embodiments, it should be appreciated that the present invention should not be construed as being limited by such embodiments, but rather construed according to the claims below. | <SOH> BACKGROUND ART <EOH>Phase-looked loop is a vitally important device. Phase-looked loop is analog and mixed signal building block used extensively in communication, networks, digital systems, consumer electronics, computers, and any other fields that require frequency synthesizing, clock recovery, and synchronization. Prior Art FIG. 1 illustrates a block diagram of a basic architecture of two types of conventional phase-locked loops, which are a conventional phase-locked loop 110 and a conventional fast-locking phase-locked loop 120 . The conventional phase-locked loop 110 typically consists of a phase-frequency detector (or phase detector), a charge-pump, a low-pass filter, and a voltage-controlled oscillator in a loop. Phase-locked loops without any frequency divider in a loop are considered here for simplicity. The phase-frequency detector (or phase detector) is a block that has an output voltage with an average value proportional to the phase difference between the input signal and the output signal of the voltage-controlled oscillator. The charge-pump either injects the charge into the low-pass filter or subtracts the charge from the low-pass filter, depending on the outputs of the phase-frequency detector (or phase detector). Therefore, change in the low-pass filter's output voltage drives the voltage-controlled oscillator. The negative feedback of the loop results in the output of the voltage-controlled oscillator being synchronized with the input signal. As a result, the phase-locked loop is in lock. In the conventional phase-locked loop 110 of Prior Art FIG. 1 , lock-in time is defined as the time that is required to attain lock from an initial loop condition. Assuming that the phase-locked loop bandwidth is fixed, the lock-in time is proportional to the difference between the input signal frequency and the initial voltage-controlled oscillator's frequency as follows: ( ω in - ω osc ) 2 ω 0 3 where ω in is the input signal frequency, ω asc is the initial voltage-controlled oscillator's frequency, and ω 0 is the loop bandwidth. The loop bandwidth must be wide enough to obtain a fast lock-in time. But most systems require a fast lock-in time without regard to the input signal frequency, bandwidth, and output phase jitter due to external noise. However, the conventional phase-locked loop 110 shown in Prior Art FIG. 1 has suffered from slow locking and harmonic locking. Thus, time and power are unnecessarily consumed until the phase-locked loops become locked. In addition, it has taken a vast amount of time to simulate and verify the conventional phase-locked loop 110 before fabrication since the simulation time of phase-locked loop circuits is absolutely proportional to time that is required the phase-locked loops to be locked. This long simulation adds additional cost and serious bottleneck to better design time to market. For these reasons, the conventional phase-locked locked loop 110 of Prior Art FIG. 1 is very inefficient to implement in an integrated circuit (IC) or system-on-chip (SOC). To overcome the drawbacks of the conventional phase-locked loop 110 of Prior Art FIG. 1 , a conventional fast-locking phase-locked loop 120 of Prior Art FIG. 1 is illustrated. The conventional fast-locking phase-locked loop 120 consists of a digital phase-frequency detector, a proportional-integral controller 122 , a 10-bit digital-to-analog converter 124 , and a voltage-controlled oscillator. Unfortunately, the conventional fast-locking phase-locked loop is costly, complicated, and inefficient to implement in system-on-chip (SOC) or integrated circuit (IC) because additional proportional-integral controller 122 and the 10-bit digital-to-analog converter 124 take much more chip area, consume much more power, and make the stability analysis very difficult. The complexity increases the number of blocks that need to be designed and verified. The conventional fast-locking phase-locked loop 120 might improve the lock-in time, but definitely results in bad time-to-market, higher cost, larger chip area, much more power consumption, and longer design time. Thus, what is desperately needed is a highly cost-effective fast-locking phase-locked loop that can be highly efficiently implemented with a drastic improvement in a very fast lock-in time, lock-in time controllability, performance, cost, chip area, power consumption, stand-by time, and fast design time for much better time-to-market. At the same time, serious harmonic locking problem has to be resolved. The present invention satisfies these needs by providing smart lock-in circuits. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention provides five types of the smart lock-in circuits for phase-locked loops. The smart lock-in circuits simultaneously enable any phase-locked loop to be locked according to schedule. The basic architecture of the smart lock-in circuits consists of a sensor, two stacked PMOS transistors, two stacked NMOS transistors, and a feedback line. The sensor senses a voltage at its input. If the sensing voltage does not reach the expected voltage compared to the midpoint voltage of the sensor, the output voltage of the sensor turns on the corresponding transistor, which provides a current to its output until the output voltage reaches the midpoint voltage. The time to reach the midpoint voltage at the filter is simply equal to the charge stored at the filter divided by the current, which can be scaled. Consequently, all smart lock-in circuits provide a significant reduction in the difference between the initial loop condition and the locked condition in order to overcome serious drawbacks simultaneously. The lock-in time controllability enables all of the phase-locked loops on the chip to be locked according to schedule. In addition, the present invention has five different embodiments which achieve a drastic improvement in a very fast lock-in time, lock-in time controllability, performance, cost, chip area, power consumption, stand-by time, and design time. | 20050115 | 20070529 | 20060720 | 98274.0 | H03L700 | 4 | GANNON, LEVI | SMART LOCK-IN CIRCUIT FOR PHASE-LOCKED LOOPS | SMALL | 0 | ACCEPTED | H03L | 2,005 |
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11,036,850 | ACCEPTED | Over-voltage test for automatic test equipment | Automatic test equipment including a digital test instrument that may test for and respond to over-voltage conditions. Information on over-voltage conditions may be used in detecting or diagnosing fault conditions within a system under test. Over-voltage conditions may be monitored as part of a test to determine the time and the channels on which they occur. A test may fail if an over-voltage condition is detected and the results of the test may indicate when and where the over-voltage condition occurred. Alternatively, indications of over-voltage conditions may be used to alter the test environment. In response to an over-voltage condition, units under test may be disconnected from the test environment to avoid exposing circuitry within those units to voltage levels that may damage or stress components. Alternatively, indications of an over-voltage condition may be used to disconnect from the test environment equipment that may be generating the over-voltage conditions. Over-voltage conditions are detected in a digital test instrument by additional comparators included in the channel electronic circuits of the test instrument. | 1. Automatic test equipment adapted to execute a user program, the test equipment: comprising a channel circuit having a signal connection point adapted to be coupled to a signal line of a unit under test to receive an input signal having a value, the channel circuit comprising: a) at least two comparison sub-circuits, each comparison sub-circuit having a signal input coupled to the signal connection point, a threshold input adapted to receive a threshold input signal having a value and a comparison output, and wherein each of the comparison sub-circuits is adapted to produce a comparison output signal at the comparison output having a value indicating the value of the input signal relative to the value of the threshold input signal; and b) control circuitry having at least two measured value inputs, each measured value input coupled to the comparison output of one of the at least two comparison sub-circuits, a test output and an over-voltage output, the control circuitry adapted to generate a test output from a first subset of the comparison output signals produced by the at least two comparison sub-circuits and to generate the over-voltage output from a second subset of the comparison output signals produced by the at least two comparison sub-circuits; and c) wherein the automatic test equipment is adapted to independently set the value of the threshold input signal for each of the at least two comparison sub-circuits based on the user program. 2. The automatic test equipment of claim 1 comprising a plurality of channel circuits, each channel circuit comprising: a) at least two comparison sub-circuits, each comparison sub-circuit having a signal input coupled to the signal connection point, a threshold input adapted to receive a threshold input signal having a value and a comparison output, and wherein each of the comparison sub-circuits is adapted to produce a comparison output signal at the comparison output having a value indicating the value of the input signal relative to the value of the threshold input signal; and b) control circuitry having at least two measured value inputs, each measured value input coupled to the comparison output of one of the at least two comparison sub-circuits, a test output and an over-voltage output, the control circuitry adapted to generate a test output from a first subset of the comparison output signals produced by the at least two comparison sub-circuits and to generate the over-voltage output from a second subset of the comparison output signals produced by the at least two comparison sub-circuits. 3. The automatic test equipment of claim 1 wherein the control circuitry comprises at least two threshold outputs, each coupled to the threshold input of one of the at least two comparison sub-circuits, and wherein the control circuitry is adapted to provide a signal having a programmable value at each of the threshold outputs. 4. The automatic test equipment of claim 1 wherein the test output of the control indicates the state of the comparison output signal of at least one of the at least two comparison sub-circuits relative to an expected state and the over-voltage output indicates the state of the comparison output signal of at least one of the at least two comparison sub-circuits. 5. The automatic test equipment of claim 4 wherein the state of the over-voltage output is based on whether the signal at the signal input has a value between the values of the signals at the threshold inputs of two of the at least two comparison sub-circuits. 6. The automatic test equipment of claim 5 additionally comprising a driver coupled to the signal connection point and disconnect circuitry connected between the output of the driver and the signal connection point, the disconnect circuitry having a control input coupled to the over-voltage output of the control circuitry. 7. The automatic test equipment of claim 6 wherein the control circuitry comprises at least one low pass filter and/or delay element coupled between the over-voltage output and the comparison outputs of the two of the at least two comparison sub-circuits. 8. The automatic test equipment of claim 2 wherein the at least two comparison sub-circuits in each of the plurality of channel circuits comprises four comparison sub-circuits and each channel circuit additionally comprises a driver. 9. Automatic test equipment of the type having a plurality of signal connection points, the automatic test equipment comprising a plurality of circuits, each of the circuits having a signal input coupled to a respective one of the signal connection points and adapted to receive as an input signal a signal at the signal connection point, the input signal having a value, with the test equipment adapted to compare the value of the input signal to at least one expected value to generate a test result, and wherein each of the circuits comprising: a) a threshold input adapted to receive at least one threshold input signal having a value; b) a comparison sub-circuit coupled to the threshold input and the signal input, the comparison sub-circuit having a comparison output indicating the value of the input signal relative to the value of the threshold input signal; and c) control circuitry having a measured value input coupled to the comparison output of the comparison sub-circuit to receive a measured value signal having a value, the control circuitry adapted to generate an output based on the value of the measured value signal, with the output being a test result and/or being an over-voltage indication. 10. The automatic test equipment of claim 9 additionally comprising a host computer operatively coupled to the control circuit to receive a value representative of the over-voltage indication. 11. The automatic test equipment of claim 10 wherein the automatic test equipment is installed in a test environment comprising a unit under test having an input coupled to the automatic test equipment and a switch coupled between the automatic test equipment and the unit under test wherein, and the host computer is programmed to actuate the switch selectively in response to the value of the over-voltage indication. 12. The automatic test equipment of claim 9 wherein each of the plurality of circuits comprises a switch having a control input, the switch coupled between the respective input signal connection point and the comparison sub-circuit, wherein the over-voltage indication is coupled to the control input of the switch. 13. The automatic test equipment of claim 9 wherein the control circuitry additionally comprises a plurality of threshold outputs coupled to the threshold input. 14. A method of operating automatic test equipment comprising: a) sensing with the automatic test equipment the signal on each of a plurality of lines; b) determining the level on each of the plurality of lines relative to an expected level; and c) determining the level on each of the plurality of lines relative to an over-voltage level. 15. The method of claim 14 additionally comprising interrupting a test in response to the level on at least one of the plurality of lines having a magnitude exceeding the over-voltage level. 16. The method of claim 14 additionally comprising opening a switch in response to the level on at least one of the plurality of lines having a magnitude exceeding the over-voltage level. 17. The method of claim 14 additionally comprising recording, for each of a plurality of cycles, an indication if the level on at least one of the plurality of lines has a magnitude exceeding the over-voltage level. 18. The method of claim 14 wherein the act of recording comprises recording an indication if the level on at least one plurality of lines has, during a programmable time interval, a magnitude exceeding the over-voltage level. 19. The method of claim 14 additionally comprising producing a failure indication during a cycle when the level on at least one of the plurality of lines either does match the expected level or exceeds the over-voltage level. 20. The method of claim 14, additionally comprising programming the time at which the test equipment determines the level on each of the plurality of lines relative to the over-voltage level. | This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Serial No. not yet assigned, entitled “OVER-VOLTAGE TEST FOR AUTOMATIC TEST EQUIPMENT,” filed on Dec. 30, 2004, which is herein incorporated by reference in its entirety. BACKGROUND OF INVENTION 1. Field of Invention This invention relates to generally to electronic systems and more specifically to test systems. 2. Discussion of Related Art Test systems are often used to verify the performance of electronic devices. An electronic device (sometimes referred to as a Unit Under Test) may be tested as a stand alone unit or may be integrated into a test environment that simulates the operating conditions of the device. The test environment may include a digital test instrument that generates and measures digital signals provided to the unit under test. The test environment may also include power supplies and instruments that generate and measure analog signals to be able to fully simulate the intended operating environment of the unit under test. The Unit Under Test (UUT) typically goes through a testing phase performed by Automatic Test Equipment (ATE). ATE operates under the control of test software, often running on a host computer. The ATE is programmed to provide stimulus to a particular circuit or component in the UUT and then measure the output to determine if the UUT has performed to its specifications. ATE may include a digital test instrument that has multiple digital channels. Each digital channel may include a driver and a detector to generate and/or measure a digital signal. The driver output and detector input may be connected together to allow for bi-directional operation. The driver circuit usually has two or more user programmable levels. Programmable drive levels allow the tester to emulate the logic family of any device they are testing. Most logic families require only two drive levels to account for a logic high and a logic low. An additional drive level can be used as an idle state or a termination level when receiving a signal. The detector circuit usually has two user programmable thresholds. Although a single threshold can be used to specify the logic state that the UUT is driving, dual-threshold detection is often used in digital channels of test equipment to verify that the UUT is driving or receiving voltages above the specified high voltage or below the specified low voltage. Conformance to these voltage specifications is required to reliably test the UUT. Some test instruments include protective circuitry that isolates circuitry in the test instrument from an input when the voltage and/or current applied at the input exceeds a rated value. Traditional and solid state fuses are used for this purpose. Also, switches have been used along with a voltage sensing circuit that activates the switch to disconnect the test instrument from an input when the voltage or current at the input exceeds a specific value. It would be desirable to have an improved test system. SUMMARY OF INVENTION In one aspect, the invention relates to automatic test equipment adapted to execute a user program. The test equipment comprises a channel circuit having a signal connection point adapted to be coupled to a signal line of a unit under test to receive an input signal having a value. The channel circuit comprises at least two comparison sub-circuits, each comparison sub-circuit having a signal input coupled to the signal connection point, a threshold input adapted to receive a threshold input signal having a value and a comparison output, and wherein each of the comparison sub-circuits is adapted to produce a comparison output signal at the comparison output having a value indicating the value of the input signal relative to the value of the threshold input signal; and control circuitry having at least two measured value inputs, each measured value input coupled to the comparison output of one of the at least two comparison sub-circuits, a test output and an over-voltage output, the control circuitry adapted to generate a test output from a first subset of the comparison output signals produced by the at least two comparison sub-circuits and to generate the over-voltage output from a second subset of the comparison output signals produced by the at least two comparison sub-circuits. The automatic test equipment is adapted to independently set the value of the threshold input signal for each of the at least two comparison sub-circuits based on the user program. In another aspect, the invention relates to automatic test equipment of the type having a plurality of signal connection points. The automatic test equipment comprises a plurality of circuits, each of the circuits having a signal input coupled to a respective one of the signal connection points and adapted to receive as an input signal a signal at the signal connection point. The test equipment is adapted to compare the value of the input signal to at least one expected value to generate a test result. Each of the circuits comprises: a threshold input adapted to receive at least one threshold input signal having a value; a comparison sub-circuit coupled to the threshold input and the signal input, the comparison sub-circuit having a comparison output indicating the value of the input signal relative to the value of the threshold input signal; and control circuitry having a measured value input coupled to the comparison output of the comparison sub-circuit to receive a measured value signal having a value, the control circuitry adapted to generate an output based on the value of the measured value signal, with the output being a test result and/or being an over-voltage indication. In a further aspect, the invention relates to a method of operating automatic test equipment comprising: sensing with the automatic test equipment the signal on each of a plurality of lines; determining the level on each of the plurality of lines relative to an expected level; and determining the level on each of the plurality of lines relative to an over-voltage level. Other aspects of the invention, as well as specific embodiments, are described below. BRIEF DESCRIPTION OF DRAWINGS The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings: FIG. 1 is a simplified block diagram of a testing environment; FIG. 2A is a circuit diagram of a portion of a digital test instrument according to one embodiment of the invention connected to a UUT; FIG. 2B is a circuit diagram of a portion of a digital test instrument according to an alternative embodiment of the invention; FIGS. 3A-3H are sketches illustrating waveforms that may be processed by a digital test system illustrated in FIG. 2A; and FIG. 4 is a simplified schematic of circuitry that may be included in digital controls 201 of FIG. 2. DETAILED DESCRIPTION This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. FIG. 1 shows a test environment 100. The test environment 100 includes automatic test equipment 139 and a system under test 189. Test environment 100 is constructed to allow verification of proper operation of a UUT within its intended operating environment. Here, system under test 189 is illustrated as containing electronic device 107, electronic device 109 and a particular unit under test, UUT 111. The configuration of the system under test 189 is not critical to the invention. But, as a specific example, electronic device 107, electronic device 109 and UUT 111 may be printed circuit cards installed in a card cage. Some or all of the cards may be connected through a digital bus 131. ATE 139 includes multiple instruments that may generate and measure signals. A host computer 120 executes a software program that controls operation of each of the instruments and receives outputs from each of the instruments. Host computer 120 may be programmed to analyze these outputs to determine whether the system under test 189 is operating properly. Such programming is traditionally a part of a user program and drives programmed values and compares measured values to expected values on one or more signal lines connected to the UUT. These steps may be programmed for multiple lines for multiple test cycles. As described in greater detail below, ATE 139 may also be programmed to specify an over-voltage threshold and use measurements indicating whether, at times which may also be programmable, an over-voltage condition has occurred. These measurements may be used to protect the test equipment, the UUT, or other components of the system. These measurements of over-voltage conditions may also be evaluated by the user program to determine whether the UUT is working properly. In the example of FIG. 1, ATE 139 includes power supply 101, digital test instrument 103 and analog test instrument 105. The numbers and types of test instruments included in ATE 139 depends on the specific system under test. The specific configuration shown should not be construed as a limitation on the invention. In FIG. 1, power supply 101 provides a relatively high current and high voltage dc signal that may be used to power electronic devices within the system under test 189. Here, power connection 133 is shown to provide a supply and return connection between power supply 101 and system under test 189. Within system under test 189, power may be distributed to the electronic devices 107, 109 and UUT 111. Digital test instrument 103 contains multiple digital channels, 211A, 211, . . . 211D. A digital channel is a circuit that interfaces to a signal connection point of the test instrument so that it can drive and receive test signals at a test point in system under test 189. For the example used herein, each test point is a line of a digital bus 131. The number of digital channels included in a digital test instrument 103 may depend on the specifics of the system under test 189. Also, in the example of FIG. 1 each of the digital channels 211A . . . 211D is illustrated to be identical. In the embodiment described herein, each digital channel is programmable such that each digital channel may perform a different function even though all digital channels have the same construction. A digital test instrument 103 may alternatively include digital channels of different designs to provide signals with different voltage levels, slew rates or other electrical characteristics. Accordingly, the specific configuration of digital test instrument 103 is not critical to the invention. In the example of FIG. 1, digital test instrument 103 is configured to interface to UUT 111 through a digital bus 131. UUT 111 includes an interface 187 to bus 131. Digital bus 131 includes multiple signal lines. In this configuration, each digital channel 211A . . . 211D may generate or measure a signal on one line of digital bus 131. Other devices, such as device 107, also may be connected to bus 131 through a similar interface, such as interface 187A. ATE 139 also includes an analog test instrument 105. Analog test instrument 105 includes multiple analog channels, here illustrated as analog channels 121 and 122. Each analog channel may generate and measure an analog test signal. Here analog channels 121 and 122 are shown connected to electronic devices 107 and 109, respectively. The specific connections are here used to illustrate principals of the invention and are not considered a limitation. In operation, host computer 120 may run a software program that causes power supply 101, digital test instrument 103 and analog test instrument 105 to generate and measure signals on lines connected to system under test 189. Based on the measured values, host computer 120 may diagnose faults in system under test 189. FIG. 1 also illustrates a problem that can arise in a test environment such as test environment 100. Power supply 101 is connected through connection 133A to digital bus 131. The output of power supply 101 may be a relatively high voltage. In contrast, the bus interface circuit 187 in UUT 111 may be designed to operate on relatively low voltage signals. For example, bus interface 187 may operate on signals having voltages less than 2.5 volts, but power supply 101 may output a voltage of 5 volts or more. A conventional test system may detect a faulty power connection such as 133A. If power supply 101 generates a positive voltage, connection 133A will cause one line of bus 131 to always have a voltage that represents a logical one. Alternatively, if power supply 101 generates a negative voltage, connection 133A would cause one of the lines in digital bus 131 to always have a voltage representing a logical zero. Such a connection would create a “stuck at zero” fault. Stuck at one and stuck at zero faults may arise in other ways. For example, a faulty output of a device connected to digital bus 131 could also create a stuck at one or a stuck at zero fault. Traditional test instruments are designed to detect stuck at one and stuck at zero faults. Even though traditional test systems may detect incorrect interconnections or operation of devices, the test system could be improved if additional information beyond merely detecting the fault could be provided. A stuck at one fault or a stuck at zero fault indicates some portion of the system under test 189 is not operating properly or is not programmed correctly. However, there is often no urgency in detecting such a fault. Circuitry within the system under test and the test instrument are designed to process signals having values that represent a logical one or a logical zero. Accordingly, no damage to the system or test instrument necessarily results even if a particular line stays at logical one or logical zero for a long time. In contrast, where a relatively high powered input is incorrectly provided to a low voltage digital device, damage to the device may occur. The damage may occur relatively quickly in a catastrophic fashion. Accordingly, it may be desirable to quickly disconnect from the test environment equipment that could be damaged by application of an over-voltage. Even when damage does not occur suddenly in a catastrophic fashion, damage from application of an over-voltage may become manifest as a premature failure of interface 187 after the electronic system is put into operation. It is not, however, necessary that a voltage be so large as to cause physical damage in order to be considered over-voltage. Any voltage that is out of bounds or otherwise outside of the specified operating range may be considered “over voltage.” Over-voltage conditions may be created in other ways. For example, an over-voltage condition may be created by improper connection of an analog channel to digital bus 131. As another example, a digital channel may be programmed to drive a voltage level that exceeds the rated voltage of a digital line. Regardless of the source of the over-voltage condition, it would be desirable to detect the over-voltage condition and react to it or record that the condition occurred for fault identification or other purposes. Test equipment according to the invention is designed to detect over-voltage situations, particularly on digital channels that are intended to receive low voltage signals. The ATE may be designed to respond to an over-voltage situation in one of multiple ways. ATE 139 may indicate to a user that a test failed when an over-voltage condition is detected. Upon failure of the test because of an over-voltage condition, ATE 139 may immediately terminate the test or continue to perform the test. If a test fails because of an over-voltage condition, information traditionally captured as a result of a test failure may be captured. For example, captured information may indicate when and where the over-voltage occurred. If the test continues after detection of an over-voltage condition, information about the number of times over-voltage conditions occur on each of the lines of the unit under test may be collected. Such information may be used for subsequent analysis to locate or correct defects in the electronic system under test 189 or the test environment 100. FIG. 2A shows a digital channel 211 that may be used to detect over voltage conditions on a line 215, which may be a portion of digital bus 131. Digital channel 211 may include circuitry that is similar to prior art digital channels. Digital channel 211 includes a driver 210 that may output a programmable signal on line 215. Driver 210 may be a driver as used in a conventional digital test instruments, whether currently known or hereafter developed. Driver 210 is coupled to line 215 through resistor 260. Resistor 260 may be used to match the output impedance of driver 210 to the impedance of line 215, but other structures for impedance matching may be used or impedance matching may be omitted. Driver 210 receives a data input 229, specifying whether driver 210 should drive a high or a low voltage on line 215. Control input 225 specifies the voltage level of the signal produced by driver 210 when it is driving a low level output. Control input 227 specifies the voltage level of the signal driven by driver 210 when it is driving a high level output. Control input 223 specifies the slew rate for the driver 210 as it transitions between a low level and high level output state. Control input 221 is an enable input. When control input 221 is disabled, driver 210 is “tri-stated,” meaning it does not source or sink current on line 215. The control inputs to driver 210 are provided by digital controls 201. Digital controls 201 may be any suitable control circuit. In one embodiment, digital controls 201 are implemented as a field programmable gate array (FPGA). However, any suitable circuit may be used to implement digital controls 201. Further, where an FPGA chip is used to implement digital controls 201, one chip may contain circuitry to control more than one digital channel. Regardless of specific implementation, digital controls 201 generate the values on control inputs 221, 223, 225, 227 and 229 for driver 210. The specific values asserted on each of the control inputs, and the times at which those values are asserted, may be derived from a test program executing on host computer 120 or in any other suitable way. Typically, a test program is executed in cycles and each digital channel may generate or measure a different value during each cycle. Digital channel 211 also includes two comparators 207 and 209 to sense the logical level of the signal on line 215. Comparators 207 and 209 may also be as in a conventional digital test instrument, whether currently known or hereafter developed. Each of the comparators 207 and 209 is coupled to the same signal connection point of digital test instrument 103 as driver 210 so that they may receive as an input the signal on line 215. Comparator 209 receives a low threshold control input 231. Low threshold control input 231 specifies the maximum value at which channel electronics 211 will indicate that a low voltage is on line 215. When the value on line 215 is less than the value specified by low threshold control input 231, the output of comparator 209 is asserted. Comparator 207 receives a high threshold control input 233. The value of high threshold control input 233 indicates the minimum value which channel electronics 211 will indicate that there is a high voltage on line 215. When the value on line 215 exceeds the high threshold control input specified on line 233, the output of comparator 207 is asserted. Both the low threshold control input 231 and the high threshold control input 233 are generated by digital controls 201. As with the controls for driver 210, the controls for comparators 207 and 209 are generated by digital control circuit 201 based on programming of a test program within host computer 120. In operation, digital control circuit 201 is programmed with the expected value on line 215. Digital control circuit 201 compares the outputs of comparators 207 and 209 to the programmed expected value. Based on the comparison, digital control circuit 201 places a value on pass/fail output 219. If the comparators 207 and 209 indicate that the value on line 215 has the expected value, the value on 219 will indicate that the comparison passed. Conversely, if the comparators 207 and 209 do not indicate that the value on line 215 has the expected value, pass/fail output 219 will have a value indicating the comparison failed. In operation, the signal on line 215 may be sensed during every cycle of operation of digital test instrument 103. The specific time during the cycle at which the value is sensed is sometimes called the “measurement window.” The time of the measurement window may also be programmed. The value on pass/fail output 219 may be recorded for each cycle of operation of channel electronics 211. The recorded pass/fail values may be analyzed to determine whether there are faults within system under test 189. Comparators 207 and 209 indicate whether the level of the signal on line 215 is above or below certain threshold levels that characterize normal operating conditions. They do not indicate the extent to which the signal is above or below the threshold. Accordingly, they do not indicate whether the voltage on line 215 is above the rated operating voltage or below the rated operating voltage of components connected to line 215. Either condition could cause damage to the components and both are referred to generically as an over-voltage condition. Comparators 203 and 205 are incorporated into digital channel 211 to detect over-voltage conditions. Comparators 203 and 205 may be of the same construction as comparators 207 and 209. However, any suitable construction for comparators 203 and 205 may be used. Comparator 205 receives a low over-voltage control input 235. Comparator 203 receives a high over-voltage control input 237. When the value on line 215 falls below the voltage specified by low over-voltage control input 235, comparator 205 asserts its output. Similarly, when the voltage on line 215 exceeds the value specified by high over voltage controlled input 237, comparator 203 asserts its output. In operation, the value of low over-voltage control input 235 and high over-voltage control input 237 are set based on the voltage levels that may cause damage to either the system under test 189 or test system 139. In a particular test environment, damage to test instrument 103 caused from unexpected signals from the UUT or other components within the test environment may be of concern. In other scenarios, damage to UUT 111 caused by unexpected signals from test system 189 or shorts within UUT 111 may be of concern. In other scenarios, damage to system 189 from improper operation of UUT may be of concern. In other scenarios, some or all of the above may be of concern. Regardless of the specific concerns, the control inputs may be set accordingly. The outputs of comparators 203 and 205 are provided to digital control circuit 201. Digital control circuit 201 includes logic that sets the value on safe/alarm output 217 based on the values output by comparators 203 and 205. If the output of either comparator 203 or 205 indicates an over-voltage condition, digital control circuit 201 sets the value on safe/alarm output 217 to indicate an over-voltage condition has occurred. Conversely, when neither the output of comparator 203 nor 205 is asserted, digital control circuit 201 sets the output on safe/alarm output 217 to indicate that no over-voltage condition occurred. The value at safe/alarm output 217 may be captured during each cycle of operation of digital channel 211 in the same way that pass/fail output 219 is captured. This information may be passed to host computer 120 to analyze the operation of the system under test 189. For example, the values on safe/alarm output 217 may be used to determine whether bus interface circuit 187 is being stressed by over-voltages. Such information may be used to predict premature failure of unit under test 111. It may also be used to diagnose unintended operating conditions that could represent either a design or manufacturing defect in system under test 189 or improper construction of test environment 100. Because the output of driver 210 and the inputs of comparators 203 and 205 are both connected to line 215, the value of safe/alarm output 217 can even indicate incorrect operation or programming of driver 210. The information at safe/alarm output 217 may be captured in a failure capture memory or other suitable circuit in the same way that information at the pass/fail output 219 is captured. It may be captured by circuitry within digital test instrument 103. It may alternatively be captured in other circuitry, such as in circuitry within host computer 120. Information from safe/alarm output 217, once captured, may be used to detect and/or diagnose the cause of over-voltage conditions. For example, the pattern of cycles in which the over-voltage condition occurs may be examined to identify a correlation between the over-voltage condition and a particular action within the test environment. For example, a correlation between an over-voltage condition on a line and electronic device 107 driving that line may indicate a fault within electronic device 107. Alternatively, it is not necessary that information from safe/alarm output 217 be captured for later processing. Safe/alarm output 217 may be used to trigger protective action. For example, host computer 120 may receive an indication from digital test instrument 103 that an over-voltage condition has occurred on a line of digital bus 131. Host computer 120 may then send control signals to switch matrix 123 that opens a switch to disconnect that line from unit under test 111. In this way, the interface circuit 187 is protected from damage from an over-voltage condition. Other immediate actions may be taken. As another alternative, a value of safe/alarm output 217 indicating an over-voltage condition may trigger termination of a test. Terminating the test may, for example, result in the device causing the over-voltage condition to be disabled. In some scenarios, it is possible that digital test instrument 103 may be the source of the failure. Terminating the test may cause digital test instrument 103 to disable control input 221 so that driver 210 is tri-stated, thereby removing the over-voltage condition. In one embodiment, comparators 203 and 205, which detect over-voltage conditions, may operate at times that are independent of the operation of comparators 207 and 209, which measure whether the signal on line 215 is a logical high or low. In this embodiment, comparators 207 and 209 may detect an over-voltage condition even when comparators 203 and 205 are not in operation, such as when driver 210 is driving a signal on line 215. In this way, comparators 203 and 205 may be controlled to detect an over-voltage condition on line 215, even an over-voltage condition caused by driver 210. FIG. 2B illustrates an alternative embodiment in which the detection of an over-voltage condition triggers an action. In the embodiment of FIG. 2B, the outputs of comparators 203 and 205 are provided to monitoring circuit 241. Monitoring circuit 241 may initiate a defined action in response to the output of either comparator 203 or 205 indicating that an over-voltage condition has occurred. In the illustration of FIG. 2B, control line 243 from monitoring circuit 241 controls switch 229. Switch 229 is a normally closed switch. It may be implemented as a solid state switch, a mechanical switch, such as a relay, or in any other suitable way. Upon detection of an over-voltage condition, monitoring circuit 241 asserts control line 243, opening switch 229. With switch 229 open, channel 211 is disconnected from line 215. If driver 210 is causing the over-voltage condition, other electronic components connected to line 215 will be protected from the over-voltage condition. Alternatively, if a device external to the digital test instrument 103 is causing the over-voltage condition, opening the switch may protect circuitry within digital test instrument 103 from damage. The output of monitoring circuit 241 may be latched so that the switch 229 stays open until it is reset. Alternatively, the output may stay asserted only for so long as one of the comparators 203 and 205 indicates an over-voltage condition exists. The output of monitoring circuit 241 may control other actions in response to an over-voltage condition. The output may alternatively or additionally be connected to one or more switches located in other positions within test environment 100. A similar protective switch may be connected to the input of each device on line 215 such that all devices are disconnected from the line if an over-voltage condition occurs. Or, similar switches may be connected across all digital lines, such that all low-voltage digital devices are disconnected in the event of an over-voltage condition, even if the condition is not detected on all lines. Turning now to FIGS. 3A to 3H, operating conditions on line 215 are shown. Here four threshold values are shown. THRESHOLD_V1 represents the value on low threshold control input 231. THRESHOLD_V2 represents the value on high threshold control input 233. THRESHOLD_V3 represents the value on low over-voltage control input 235. THRESHOLD_V4 represents the value on high over-voltage control input 237. FIG. 3A shows one cycle of a signal on line 215. In a sample window 310A, the signal has a value above THRESHOLD_V2 and below THRESHOLD_V4. When channel 211 is programmed to expect a HI signal, this signal level matches the expected result. Accordingly, pass/fail output 219 has a value indicative of a “pass” result, which is represented by the legend of FIG. 3A stating “RESULT=PASS.” The signal level is below THRESHOLD_V4 and above THRESHOLD_V3. This voltage does not correspond to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is no over-voltage condition, which is represented by the legend of FIG. 3A stating “ALERT=NONE.” FIG. 3B shows a subsequent cycle of the signal on line 215. In a sample window 310B, the signal has a value that is above THRESHOLD_V1 but below THRESHOLD_V2. This value corresponds to neither a HI nor a LO, and will result in no match with the expected value. Accordingly, pass/fail output 219 has a value indicative of a “fail” result. The signal level is below THRESHOLD_V4 and above THRESHOLD_V3. This voltage does not correspond to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is no over-voltage condition. FIG. 3C shows a further cycle of the signal on line 215. In a sample window 310C, the signal has a value above both THRESHOLD_V2 and THRESHOLD_V4. When channel 211 is programmed to expect a HI signal, this signal level matches the expected result. Accordingly, pass/fail output 219 has a value indicative of a “pass” result. The signal level is above the high over-voltage control input. This voltage corresponds to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is an over-voltage condition. In the example of FIG. 3C, digital test instrument 103 is programmed so that the value on the pass/fail output 219 is independent of the value on safe/alarm output 217. FIG. 3D shows a further cycle of the signal on line 215. In sample window 310D, the signal has a value above THRESHOLD_V2 and below THRESHOLD_V4. When channel 211 is programmed to expect a HI signal, this signal level matches the expected result. Accordingly, pass/fail output 219 has a value indicative of a “pass” result. The signal level is below the high over-voltage control input and above the low over-voltage control input. This voltage does not correspond to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is no over-voltage condition. FIG. 3D shows a transient 320D that momentarily exceeds THRESHOLD_V4. However, in the example illustrated, digital test instrument 103 is configured to ignore switching transients by only using the outputs of comparators 203 and 205 during a sample window 310D to set the value of safe alarm output 217. As in conventional digital test instrument, the timing of the sample window may be programmed. In this example, the time of sample window 310D is selected to be after switching transients at the start of a cycles have died away. FIG. 3E shows a further cycle of the signal on line 215. In a sample window 310E, the signal has a value below THRESHOLD_V1. When channel 211 is programmed to expect a LO signal, this signal level matches the expected result. Accordingly, pass/fail output 219 has a value indicative of a “pass” result. The signal level is above THRESHOLD_V3 and below THRESHOLD_V4. This voltage does not correspond to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is no over-voltage condition. FIG. 3F shows a further cycle of the signal on line 215. In a sample window 310F, the signal has a value above THRESHOLD_V1 and below THRESHOLD_V2. This value corresponds to neither a HI nor a LO, and will result in no match with the expected value. Accordingly, pass/fail output 219 has a value indicative of a “fail” result. The signal level is below THRESHOLD_V4 and above THRESHOLD_V3. This voltage does not correspond to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is no over-voltage condition. FIG. 3G shows a further cycle of the signal on line 215. In a sample window 310G, the signal has a value below both THRESHOLD_V1 and THRESHOLD_V3. When channel 211 is programmed to expect a LO signal, this signal level matches the expected result. However, in this example, digital test instrument 103 is programmed to issue a “fail” test result in any over-voltage situation. In this example, the signal level is below the low over-voltage control input. This voltage corresponds to an over-voltage condition. Accordingly, the value on safe/alarm output 217 indicates that there is an over-voltage condition and the value on pass/fail output 219 indicates a “fail.” FIG. 3H shows a further cycle of the signal on line 215. In sample window 310H, the signal has a value below THRESHOLD_V1. When channel 211 is programmed to expect a LO signal, this signal level matches the expected result. Accordingly, pass/fail output 219 has a value indicative of a “pass” result. In the sample window 310H, the signal level is below the high over-voltage control input and above the low over-voltage control input. This voltage does not correspond to an over-voltage condition. However, in the cycle illustrated in FIG. 3H, the signal undergoes a transient 320H. Transient 320H has a peak that is below THRESHOLD_V3. In this embodiment, digital test instrument 103 is constructed to be sensitive to any over-voltage condition during a cycle of duration 312H, and not just during a sample window. Accordingly, the value on safe/alarm output 217 indicates that there is an over-voltage condition. FIGS. 3A . . . 3H illustrate various possible methods of operation of digital test instrument 103. The over-voltage indication may be based on signal levels at a programmed time or may reflect a signal level exceeding a threshold at any time. The pass/fail output may indicate a fail result, regardless of expected value if an over-voltage condition occurs or the pass/fail output may be set independently of the over-voltage condition. In one embodiment, digital test instrument 103 is programmable such that digital controls 201 will produce the desired operating characteristics. Digital controls 201 may be implemented in any suitable way to provide the desired programmable control. For example, FIG. 4 shows circuitry that may be included in digital controls 201 to provide the desired programmability. A programmed expect value gates the outputs of comparators 207 and 209. The output of comparator 207 is applied as an input to AND gate 410. The output of AND gate 410 is a logical high when the expected value is a logical high and the output of comparator 207 indicates the signal in 215 has a value exceeding the high threshold control input. The output of comparator 209 is applied as an input to AND gate 412. The second input to AND gate 412 is an inverting input, which receives the expected value signal. The output of AND gate 412 is a logical high when the expected value is a logical low and the output of comparator 209 is a logical high, indicating that the signal on line 215 is below the low threshold controlled input. The outputs of AND gate 410 and 412 are combined at NOR gate 414 to produce a signal indicating that a failure has occurred. The output of NOR gate 414 is a logical high when neither AND gate 410 nor 412 indicates that the programmed expected value was detected. The output of NOR gate 414 is gated through AND gate 415 and captured in flip-flop 416. The second input to AND gate 415 is a TW control signal. The TW control signal is a programmable signal. The timing of the TW control signal may be programmed to specify a sample window. If a failure occurs while the TW signal is asserted, the output of NOR gate 414 will be asserted. The output of NOR gate 414 will be gated through AND gate 415, causing the set input of flip-flop 416 to be asserted. The output of flip-flop 416 will stay asserted until the RESET signal is applied, which in this example, is applied after the sample window. If the output of NOR gate 414 indicates an unexpected operating condition at any time other than when the TW control signal is asserted, it is not gated through AND gate 415 and has no impact on the output of flip-flop 416. The output of comparators 203 and 205 are provided to OR gate 450. The output of OR gate 450 indicates that the signal on line 215 has a voltage level that exceeds the high over-voltage control input or is below the low over-voltage control input. In this embodiment either condition is regarded as an over-voltage condition. The output OR gate 450 is gated through AND gate 451 and captured in flip-flop 452. The second input to AND gate 451 is the TW control signal. If an over-voltage condition occurs while the TW signal is asserted, the output of OR gate 450 will be asserted. The output of OR gate 450 will be gated through AND gate 451, causing the set input of flip-flop 452 to be asserted. The output of flip-flop 452 will stay asserted until the RESET signal is applied, which in this example, is applied after the sample window. If the output of OR gate 450 indicates an over-voltage condition at any time other than when the TW control signal is asserted, it will not be gated through AND gate 451 and has no impact on the output of flip-flop 452. In the example of FIG. 4, flip-flop 452 is controlled by the same control input as flip-flop 416. However, the flip-flops may be independently controlled. The output of OR gate 450 is also provided in a parallel path to the set input of flip-flop 454. If the set input to flip-flop 454 becomes a logical high at any time that flip-flop 454 is enabled, the output of flip-flop 454 will latch in a logical high state. The output of flip-flop 454 will stay in a logical high state until flip-flop 454 receives a reset input. The reset input to flip-flop 454 is also a programmable signal. Flip-flop 454 may, for example, be reset once per cycle of digital test instrument. In this scenario, flip-flop 454 indicates whether an over-voltage condition occurred at any time during the cycle. Alternatively, flip-flop 454 may be reset once per test. In this scenario, the output of flip-flop 454 indicates that an over-voltage condition occurred during the test. The outputs of flip-flop 450 and flip-flop 454 are provided to a multiplexer 456. Multiplexer 456 has a programmable control input S2. The value of S2 may be set to select with multiplexer 456 either the output of flip-flop 452 or the output of flip-flop 454. When multiplexer 456 selects the output of flip-flop 452, safe/alarm output 217 indicates whether an over-voltage condition occurred during the sample window specified by the TW control signal. Alternatively, when multiplexer 456 selects the output of flip-flop 454, safe/alarm output 217 indicates that an over-voltage condition occurred, regardless of whether the over voltage condition occurred during the sample window. The circuit of FIG. 4 also includes a multiplexer 418 that allows pass/fail output 219 to be programmed to reflect the results of safe/alarm output 217 or to be independent of the value of safe/alarm output 217. When control input S1 to multiplexer 418 selects the output of flip-flop 416, the value of pass/fail output 219 is independent of the value of safe/alarm output 217. The second input to multiplexer 418 is generated by combining at OR gate 462 the output of flip-flop 416 with the safe/alarm output 217. If either safe/alarm output 217 indicates that an over-voltage condition has been detected or the output of flip-flip 416 indicates a test failure occurred because the measured value did not match the expected value, the output of OR gate 462 will indicate a failure. Conversely, when safe/alarm output 217 indicates no over-voltage condition has occurred and the output of flip-flop 416 indicates no failure was detected, the output of OR gate 462 will take on a value indicating a pass. Having thus described several aspects of at least one embodiment of this invention, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. For example, it is described that operating conditions in which the voltage on a line is higher than a specified level or lower than a specified level are both over-voltage conditions. It is not necessary that conditions in which the voltage is too low and conditions in which the voltage is too high be represented the same way. The conditions could be represented as an over-voltage and an under-voltage condition and a test program may record or respond to an over-voltage and an under-voltage condition differently. As another example, drivers and comparators are shown connected directly to a signal line 215. A channel may include impedance matching elements, buffer amplifiers, signal dividers, switches and/or other circuit elements through which the drivers and comparators may be coupled to the signal connection point of the test instrument. Other circuit elements may be connected to the signal connection point, such as an active load. As a further example, signals may be coupled to any or all of the comparators through circuitry that processes differential input signals, to allow the test system as described above to operate on either single ended or differential signals. The processing may result in either the differential or common mode components of a differential signal being applied to one or more comparators. As a result, the test equipment may determine whether a differential signal has an expected value of its differential and/or common mode component and whether or not the differential and/or common mode component is out of bounds. Where the test instrument operates on differential signals, and it is determined that the signal is out of bounds, a connection in the system may be interrupted. The connection could be to the test instrument, the UUT or to another component of the test environment that is believed to be creating the out of bounds condition. When breaking a connection carrying a differential signal, it may be preferable to disconnect both legs of the differential signal. As a further example of the embodiments that are possible, FIG. 2B shows a switch 229 controlled by a hardware component, in this example, a monitoring circuit 241. In contrast, FIG. 1 shows a switch matrix 123. Switch matrix 123 is controlled by signals from host computer 121. The control signals from host computer 121 may be generated by software executing on host computer 121 or may be generated by special hardware installed in host computer 121. Regardless of the specifics of implementation, a switch may be opened in response to over-voltage values sensed. Further, protective switches are shown to be normally closed switches that open to break a connection when activated. As an alternative, switches could be normally open and close to create a path to ground in the event of an over-voltage condition. A further example, digital test instrument 103 may include other circuitry to process the outputs of comparators 203 and 205. For example, monitoring circuit 241 (FIG. 2B) may be designed to avoid triggering on a transient over-voltage condition, such as shown in FIG. 3D or 3H. Monitoring circuit 241 may contain a circuit that has a low pass filter characteristics and therefore acts as a low pass filter. The circuit could perform other signal processing functions or could perform only the low pass filter function. The low pass filter may be a digital low pass filter. Alternatively, the low pass filter could be implemented in whole or in part with analog signal processing techniques. Filtering the output of comparators 203 and 205 reduces the effect of transient portions of the signal output by comparators 203 and 205. A low pass filter or delay element is therefore desirable in circumstances where it is desirable not to trigger an alarm output when the voltage on line 215 momentarily exceeds a set level. Furthermore, drivers and comparators are shown connected to the same signal lead to allow bidirectional operation of each channel. The invention could be employed where separate channels are used to drive and receive a signal connection point. Likewise, separate comparators are shown to measure expected values during a test and to detect over-voltage conditions. It is not necessary that separate comparators be present. The same comparator circuit could be used to make a test measurement and an over-voltage measurement. For example, the comparator could be programmed with different threshold values to, at one time, be a test comparator and, at other times, be an over-voltage comparator. In a similar fashion, the outputs of digital control circuit 201 could be multiplexed. For example, one output could, at one time, be a line representing whether the value on line 215 has an expected value and at other times could be a line representing whether the value on line 215 is in an over-voltage state. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawings are by way of example only. | <SOH> BACKGROUND OF INVENTION <EOH>1. Field of Invention This invention relates to generally to electronic systems and more specifically to test systems. 2. Discussion of Related Art Test systems are often used to verify the performance of electronic devices. An electronic device (sometimes referred to as a Unit Under Test) may be tested as a stand alone unit or may be integrated into a test environment that simulates the operating conditions of the device. The test environment may include a digital test instrument that generates and measures digital signals provided to the unit under test. The test environment may also include power supplies and instruments that generate and measure analog signals to be able to fully simulate the intended operating environment of the unit under test. The Unit Under Test (UUT) typically goes through a testing phase performed by Automatic Test Equipment (ATE). ATE operates under the control of test software, often running on a host computer. The ATE is programmed to provide stimulus to a particular circuit or component in the UUT and then measure the output to determine if the UUT has performed to its specifications. ATE may include a digital test instrument that has multiple digital channels. Each digital channel may include a driver and a detector to generate and/or measure a digital signal. The driver output and detector input may be connected together to allow for bi-directional operation. The driver circuit usually has two or more user programmable levels. Programmable drive levels allow the tester to emulate the logic family of any device they are testing. Most logic families require only two drive levels to account for a logic high and a logic low. An additional drive level can be used as an idle state or a termination level when receiving a signal. The detector circuit usually has two user programmable thresholds. Although a single threshold can be used to specify the logic state that the UUT is driving, dual-threshold detection is often used in digital channels of test equipment to verify that the UUT is driving or receiving voltages above the specified high voltage or below the specified low voltage. Conformance to these voltage specifications is required to reliably test the UUT. Some test instruments include protective circuitry that isolates circuitry in the test instrument from an input when the voltage and/or current applied at the input exceeds a rated value. Traditional and solid state fuses are used for this purpose. Also, switches have been used along with a voltage sensing circuit that activates the switch to disconnect the test instrument from an input when the voltage or current at the input exceeds a specific value. It would be desirable to have an improved test system. | <SOH> SUMMARY OF INVENTION <EOH>In one aspect, the invention relates to automatic test equipment adapted to execute a user program. The test equipment comprises a channel circuit having a signal connection point adapted to be coupled to a signal line of a unit under test to receive an input signal having a value. The channel circuit comprises at least two comparison sub-circuits, each comparison sub-circuit having a signal input coupled to the signal connection point, a threshold input adapted to receive a threshold input signal having a value and a comparison output, and wherein each of the comparison sub-circuits is adapted to produce a comparison output signal at the comparison output having a value indicating the value of the input signal relative to the value of the threshold input signal; and control circuitry having at least two measured value inputs, each measured value input coupled to the comparison output of one of the at least two comparison sub-circuits, a test output and an over-voltage output, the control circuitry adapted to generate a test output from a first subset of the comparison output signals produced by the at least two comparison sub-circuits and to generate the over-voltage output from a second subset of the comparison output signals produced by the at least two comparison sub-circuits. The automatic test equipment is adapted to independently set the value of the threshold input signal for each of the at least two comparison sub-circuits based on the user program. In another aspect, the invention relates to automatic test equipment of the type having a plurality of signal connection points. The automatic test equipment comprises a plurality of circuits, each of the circuits having a signal input coupled to a respective one of the signal connection points and adapted to receive as an input signal a signal at the signal connection point. The test equipment is adapted to compare the value of the input signal to at least one expected value to generate a test result. Each of the circuits comprises: a threshold input adapted to receive at least one threshold input signal having a value; a comparison sub-circuit coupled to the threshold input and the signal input, the comparison sub-circuit having a comparison output indicating the value of the input signal relative to the value of the threshold input signal; and control circuitry having a measured value input coupled to the comparison output of the comparison sub-circuit to receive a measured value signal having a value, the control circuitry adapted to generate an output based on the value of the measured value signal, with the output being a test result and/or being an over-voltage indication. In a further aspect, the invention relates to a method of operating automatic test equipment comprising: sensing with the automatic test equipment the signal on each of a plurality of lines; determining the level on each of the plurality of lines relative to an expected level; and determining the level on each of the plurality of lines relative to an over-voltage level. Other aspects of the invention, as well as specific embodiments, are described below. | 20050114 | 20080701 | 20060720 | 77980.0 | G06F1100 | 1 | CHUNG, PHUNG M | OVER-VOLTAGE TEST FOR AUTOMATIC TEST EQUIPMENT | UNDISCOUNTED | 0 | ACCEPTED | G06F | 2,005 |
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11,036,956 | ACCEPTED | Ad hoc networking of terminals aided by a cellular network | A fast and secure ad hoc communication system is established between terminals with the aid of a network. Terminals equipped with a non-cellular interface may establish a high data rate peer-to-peer or multi-hop ad hoc connection with the support of a cellular network. The cellular network may provide signaling for user authentication, peer identification, key distribution for a secure non-cellular connection set-up, radio resources management messages, routing assistance information, as well as charging and billing for the service. A non-cellular link may be used for fast and secure ad hoc communication between the terminals. Signaling may be transported either over a non-cellular access network or, using dual-mode terminals, over the cellular RAN. A combination of the signaling transports is also possible. | 1. A method for ad hoc networking of terminals over a non-cellular interface aided by a cellular network, comprising: determining the identities of the terminals desiring to establish an ad hoc link; determining a network associated with the terminals; choosing a signaling transport for the terminals; and. establishing a secure connection in an ad hoc manner between the terminals with the aid of the cellular network. 2. The method of claim 1, further comprising enforcing rules relating to the ad hoc link. 3. The method of claim 1, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises using a cellular infrastructure. 4. The method of claim 1, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises receiving an identifier from the terminal. 5. The method of claim 1, wherein determining the network associated with the terminals, further comprises determining when a terminal is coupled to a non-cellular network and determining when the terminal is coupled to a cellular network. 6. The method of claim 1, further comprising receiving update information relating to the terminals. 7. The method of claim 6, further comprising determining when a terminal desires to communicate, and when: the terminal asking assistance from a central register; and providing the terminal with an answer optimized for the terminal. 8. The method of claim 7, wherein providing the terminal with the answer optimized for the terminal, further comprises providing a route to the terminal. 9. The method of claim 8, wherein the route may be a single hop connection route or a multi-hop connection route or a recommendation to use the cellular network. 10. The method of claim 7, further comprising charging for the aid of the cellular network. 11. The method of claim 5, wherein the cellular network associated with the terminal is contacted over multi-hop signaling. 12. The method of claim 5, wherein choosing the signaling transport media for the terminals, further comprises choosing a non-cellular access network to carry the signaling for non-cellular-only terminals. 13. The method of claim 5, wherein the signaling for the terminals may be carried across a cellular radio access network. 14. A system for ad hoc networking of terminals aided by a cellular network, comprising: terminals, wherein the terminals include an interface unit arranged to communicate with a cellular network, wherein the cellular network is configured to: communicate with terminals; determine the identity of the terminals that desire to establish an ad hoc link; determine a network associated with the terminals; choose a signaling transport for the terminals; and establish a secure link in an ad hoc manner with the terminals. 15. The system of claim 14, wherein communication with terminals may be selected from a direct communication link and an indirect communication link. 16. The system of claim 14, further comprising a means operative to enforce rules associated with the secure link. 17. The system of claim 14, further comprising a central register that is configured to receive update information relating to the terminals. 18. The system of claim 17, wherein the central register is further configured to determine when a terminal desires to communicate by receiving a request from a terminal, and when: the terminal configured to ask assistance from the central register; and the central register configured to provide the terminal with an answer optimized for the terminal relating to the communication. 19. The system of claim 18, wherein providing the terminal with the answer, further comprises the central register configured to provide route information to the terminal. 20. The system of claim 19, wherein the route information may be a single hop connection route or a multi-hop connection route or a recommendation to use the cellular network. 21. The system of claim 17, wherein the central register is further configured to charge for the aid of the cellular network. 22. The system of claim 14, wherein the signaling transport may be over a noncellular access network and a cellular radio access network. 23. The system of claim 22, wherein the cellular network is configured to determine the identity of the terminals that desire to establish an ad hoc link further comprises receiving an identifier from the terminals. 24. The system of claim 23, wherein the identifier may be selected from a group including a user name, a user address, an IMSI code, an ISDN telephone number and an NAI. 25. The system of claim 23, wherein the identifier is communicated over a written note, a verbal communication, an RF tag, and a bar code. 26. The system of claim 14, wherein the cellular network is further configured to authenticate the terminal and deliver at least one encryption key for a secure link establishment. 27. The system of claim 14, wherein the cellular network is further configured to deliver at least one security association token. 28. The system of claim 14, wherein the cellular network is further configured to charge for services provided. 29. A system for ad hoc networking of terminals over a non-cellular interface aided by a cellular network, comprising: means for determining the identities of the terminals desiring to establish an ad hoc link; means for determining a network associated with the terminals; means for choosing a signaling transport for the terminals; means for establishing a secure connection in an ad hoc manner between the terminals with the aid of the cellular network; and means for enforcing rules relating to the ad hoc networking. 30. A method for ad hoc networking of terminals aided by a cellular network, wherein the terminals include an interface unit arranged to communicate with a cellular network, and an interface unit arranged to communicate with an ad hoc network, wherein the method comprises: sending an identifier from the terminal to the cellular network; asking assistance from the cellular network for establishing a communication link; receiving an answer from the cellular network optimized for the terminal relating to the communication; and establishing a communication link in an ad hoc manner with the other terminal based on the received answer. 31. The method of claim 30, wherein establishing a communication link with the other terminal further comprises utilizing security and authentication information. 32. The method of claim 31, wherein the security and authentication information is received from the cellular network. 33. The method of claim 31, wherein establishing the communication link further comprises establishing an ad hoc link. 34. A terminal enabled for ad hoc networking aided by a cellular network, comprising: a cellular network interface unit arranged to communicate with a cellular network; and an ad hoc interface unit arranged to communicate with an ad hoc network; wherein the terminal is arranged to: send an identifier to the cellular network; ask assistance from the cellular network for establishing a communication link; receive an answer from the cellular network optimized for the terminal relating to the communication link; and establish the communication link in an ad hoc manner with another terminal based on the received answer. 35. The terminal of claim 34, wherein the terminal is further arranged to utilize security and authentication information received from the cellular network to establish the communication link. 36. A network node associated with a cellular network for providing services associated with an ad hoc network, the network node comprising: means for forming a description of an ad hoc network of terminals, wherein the ad hoc network is formed over a non-cellular interface; means associated with the cellular network for receiving from a terminal a request for assistance in relation to establishing a communication link to another terminal over the ad hoc network using the non-cellular interface; and means for providing an optimized answer to the terminal in response to the request for assistance. 37. The network node of claim 36, wherein the means for forming the description of the ad hoc network further comprises receiving information regarding status updates from terminals associated with ad hoc networking. 38. The network node of claim 37, wherein providing the terminal with the optimized answer to the terminal, further comprises providing a route to the terminal. 39. The network node of claim 38, wherein the route may be a single hop connection route or a multi-hop connection route. 40. The network node of claim 39, wherein the route may be a recommendation to use the cellular network. 41. The network node of claim 37, wherein the optimized answer further comprises authentication and security information for a secure link establishment. 42. An apparatus associated with a cellular network for providing services associated with an ad hoc network, the apparatus comprising: means for forming a description of an ad hoc network for terminals associated with the ad hoc network, wherein the ad hoc network is formed over a non-cellular interface; means associated with the cellular network for receiving from a terminal a request for assistance in relation to establishing a communication link to another terminal over the ad hoc network using the non-cellular interface; and means for providing an optimized answer to the terminal in response to the request for assistance. 43. A cellular network comprising: a central register configured and arranged to determine identities of terminals desiring to establish an ad hoc link over a non-cellular interface; determine a network associated with the terminals; choose a signaling transport for the terminals; and assist in establishing the ad hoc link between the terminals over the non-cellular interface. 44. The cellular network of claim 43, wherein the central register comprises a server. 45. The cellular network of claim 43, wherein the ad hoc link is a WLAN ad hoc link. 46. The cellular network of claim 43, wherein the central register is configured and arranged to assist in establishing the ad hoc link between the terminals over a secure connection. 47. The cellular network of claim 43, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises using a cellular infrastructure. 48. The cellular network of claim 43, wherein the central register is configured and arranged to receive update information relating to the terminals and form a description of an ad hoc network in response to receiving the update information. 49. A computer-readable medium storing instructions causing a computer program to execute a computer process for ad hoc networking of terminals over a non-cellular interface aided by a cellular network, the instructions comprising: determining the identities of the terminals desiring to establish an ad hoc link; determining a network associated with the terminals; choosing a signaling transport for the terminals; and establishing an ad hoc connection over the non-cellular interface between the terminals with the aid of the cellular network. 50. The computer-readable medium of claim 49, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises using a cellular infrastructure. 51. The computer-readable medium of claim 49, wherein establishing an ad hoc connection comprises establishing a secure ad hoc connection between the terminals. 52. A modulated data signal for communicating content over a cellular network, the modulated data signal comprising: determining the identities of the terminals desiring to establish an ad hoc link; determining a network associated with the terminals; choosing a signaling transport for the terminals; and establishing an ad hoc connection over the non-cellular interface between the terminals with the aid of the cellular network. 53. The modulated data signal of claim 52, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises using a cellular infrastructure. 54. The modulated data signal of claim 52, wherein establishing an ad hoc connection comprises establishing a secure ad hoc connection between the terminals. 55. A method for ad hoc networking of terminals over a non-cellular interface aided by a cellular network, comprising: determining the identities of the terminals desiring to establish an ad hoc link; determining a network associated with the terminals; choosing a signaling transport for the terminals; and. aiding the establishment an ad hoc connection between the terminals using the cellular network. 56. The method of claim 55, wherein determining the identities of the terminals desiring to establish an ad hoc link further comprises using a cellular infrastructure. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation of co-pending U.S. patent application Ser. No. 10/179,397, filed Jun. 24, 2002, and which is incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to IP networks, and more particularly to establishing ad hoc networking among terminals aided by a cellular network. BACKGROUND OF THE INVENTION The development of mobile communication devices and mobile networks has advanced at a rapid rate. At first, analog mobile networks enabled voice communication and simple paging features. Later, digital mobile networks provided more advanced features for voice and data communication, such as encryption, caller identification and short message service (SMS) text messages. More recently, third generation (3G) mobile IP network technology is being developed to enable users to easily access content rich media, information and entertainment with mobile devices. As networks advance, WLAN cellular networking is becoming an intensely discussed issue. Many see WLAN as an important component in the 3G evolution. For example, 3GPP is currently conducting feasibility studies on WLAN/UMTS interworking. The interest is not limited to 3GPP only but has also drawn attention at 3GPP2 and the Mobile Wireless Internet Forum (MWIF). Other evolution paths for interworking between cellular networks and ad hoc capable networks can be seen in e.g. Bluetooth, Infrared and Wireless Routing (WR). Exchanging data between two mobile terminals may be costly if conducted over the cellular infrastructure or if the terminals are co-located. Using a WLAN, Bluetooth or Infrared, or any other peer-to-peer interface for keeping a high rate (and possibly also volume) traffic local is efficient from a cost, bandwidth and spectrum usage point of view. Current WLAN, infrared (IR) and emerging Bluetooth/IEEE 802.15 (BT) standards would allow for the interface, but it is very difficult and clumsy to achieve a desired trusted security level between the terminals. Typically the connection set-up has would be done manually. Additionally, cellular operator revenue is lost when only using a WLAN/BT/IR/WR, or other non-cellular connection. A problem, however, is that current solutions offer limited functionality and usability. Current connection setup is standardized, e.g., for WLAN in IEEE 802.11b. What is needed is a way to establish secure links using cellular operator-controlled devices and a way for an operator to be involved in local traffic exchange that bypasses the infrastructure and thus offers a tool for additional revenue that would otherwise escape the operator. It is with respect to these considerations and others that the present invention has been made. SUMMARY OF THE INVENTION The present invention is directed at addressing the above-mentioned shortcomings, disadvantages and problems, and will be understood by reading and studying the following specification. According to one aspect of the invention, mobile nodes equipped with a non-cellular wireless interface may establish a high data rate peer-to-peer ad hoc connection with the support of a cellular network. The cellular network may provide signaling for user authentication, peer identification, authentication key distribution for a secure non-cellular connection set-up, radio resources management messages, as well as charging and billing for the service. This is especially true, if one of the terminals is a server of music, games, streaming video, and the like. According to another aspect of the invention, the non-cellular link may be used for fast and secure ad hoc communication between the terminals. Signaling may be carried either over a non-cellular wireless access network or, using dual-mode terminals, over the cellular Radio Access Network (RAN). A combination of the signaling transport media is also possible. For example, one user may carry signaling over a WLAN RAN and the other user may carry signaling over a cellular system. According to yet another aspect of the invention, the cellular system is not limited to the Universal Mobile Telecommunications System (UMTS). Cellular network, as used in this application refers to any mobile network operated by an operator. For example, without limiting to these, the cellular network can be a GSM, GPRS, UMTS, using various radio access network technologies, such as CDMA2000, WCDMA and WLAN. Similarly, the non-cellular network and interface for the ad-hoc link may be any of the family of short range radios including BRAN Hiperlan, Hiperlan2, IEEE 802.11a, b, g, Multimedia Mobile Access Communication (MMAC) High-Speed Wireless Access (HISWA), Bluetooth, IEEE 802.15, and the like. The short range connection may even be a wired or infrared connection without departing from the spirit of this invention. According to a further aspect of the invention, a cellular infrastructure is used to identify and authenticate the mobile users, and deliver one or more encryption keys or tokens for a secure non-cellular link establishment. Number and kind of needed encryption keys or security association tokens is dependent on the security method(s) employed in the network, which is not a part of this invention. Any kind of suitable security method(s) can be employed in accordance to this invention. This eases the process and possibly generates additional revenue for an operator. For instance, the authentication and encryption (security) signaling services provided by the cellular network could be charged for. Another example for chargeable services can be routing assistance based on a dynamically updated register in the cellular network, which creates a description of the ad hoc network and provides optimized routing information for mobile nodes based on that description. Yet another example of such chargeable services is QoS (quality of service) support provided by the cellular infrastructure and supervised by the operator. In addition, if one of the terminals offers commercial services, this arrangement allows reusing the cellular billing infrastructure for charging for the service. According to still yet another aspect of the invention, a terminal is provided, which is able to communicate over ad hoc communication links with assistance provided from the cellular network for establishing the communication. The terminal receives information optimized for the terminal from the cellular network used in establishing communication links. According to a further aspect of the invention, a network node associated with cellular network for providing services associated with an ad hoc network can form descriptions of an ad hoc network for terminals associated with an ad hoc network. The network node receives requests for assistance from terminals for assistance in establishing a communication link. In response to the request, the network node provides an optimized answer to the terminal. The optimized answer may provide information relating to routing, quality enhancement, and security and authentication. According to one embodiment of the invention, the network node provides server or register functionality. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an exemplary cellular network in which the invention may operate; FIG. 2 shows a schematic diagram that illustrates an exemplary system overview in which local area networks and a wide area network are interconnected by routers; FIG. 3 shows exemplary ad hoc networking of terminals over a Non-Cellular interface aided by a cellular network; FIG. 4 shows exemplary ad hoc network in which some of the terminals employ a non-direct connection (i.e. a multi-hop connection) to the cellular network; FIG. 5 illustrates an operator controlled central register system; and FIG. 6 illustrates a process for ad hoc networking of terminals over a Non-cellular interface aided by a cellular network, in accordance with aspects of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanied drawings, which form a part hereof, and which is shown by way of illustration, specific exemplary embodiments of which the invention may be practiced. Each embodiment is described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims. Throughout the specification and claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise. The term “node” refers to a node on a network. The term “mobile node” and “terminal” refer to a node on the network that is mobile. The term “flow” means a flow of packets. The term “support node” refers to both “GGSN” and “SGSN” nodes. The term “user” refers to any person or customer such as a business or organization that employs a mobile device to communicate or access resources over a mobile network. The term “operator” refers to any technician or organization that maintains or services something, such as a network. The term “identifier” refers to a user address, an IMSI code, an MSISDN number, an IP address, or any other information that relates to the location or identity of the user or equipment. In an exemplary implementation described in this application, AAA (Authentication, Authorization and Accounting) device is referred. AAA is an IETF standard developed by the Authentication, Authorization and Accounting (AAA) Working Group. The work of this group is ongoing, and a reference is made to the proceedings of this working group, both existing and forthcoming, (http://www.ietf.org/html.charters/aaa-charter.html) in its entirety. Instead of AAA, any other existing or future system and method can be employed for authentication, authorization and accounting without departing from the spirit of this invention. The term “AAA device” refers to any device that offers the functionality of an AAA server generally associated with an IP network. Other nodes or systems of cellular networks may offer the AAA functionality. There include, but are not limited too, entities as charging centers, gateways, resource management entities, user profiles stored in location registers, etc. Referring to the drawings, like numbers indicate like parts throughout the views. Additionally, a reference to the singular includes a reference to the plural unless otherwise stated or is inconsistent with the disclosure herein. Illustrative Operating Environment With reference to FIG. 1, an exemplary cellular network coupled with data networks, in which the invention may operate is illustrated. As shown in the figure, network 100 includes mobile node (MN) 105, radio access network (RAN) 110, SGSN 115, core network 120, routers 125D-F, optional authentication, authorization, and accounting (AAA) server 300, GGSNs 135A-B, data network 140, and data network 145. The connections and operation for network 100 will now be described. MN 105 is coupled to radio access network (RAN) 110. Generally, MN 105 may include any device capable of connecting to a wireless network such as radio access network 110. Such devices include cellular telephones, smart phones, pagers, radio frequency (RF) devices, infrared (IR) devices, integrated devices combining one or more of the preceding devices, and the like. MN 105 may also include other devices that have a wireless interface such as Personal Digital Assistants (PDAs), handheld computers, personal computers, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, wearable computers, and the like. Radio Access Network (RAN) 110 manages the radio resources and provides the user with a mechanism to access core network 120. Radio access network 110 transports information to and from devices capable of wireless communication, such as MN 105. Radio access network 110 may include both wireless and wired components. For example, radio access network 110 may include a cellular tower that is linked to a wired network. Typically, the cellular tower carries communication to and from cell phones, pagers, and other wireless devices, and the wired network carries communication to regular phones, long-distance communication links, and the like. Some nodes may be General Packet Radio Service (GPRS) nodes. For example, Serving GPRS Support Node (SGSN) 115 may send and receive data from mobile nodes, such as MN 105, over RAN 110. SGSN 115 also maintains location information relating to MN 105. SGSN 115 communicates between MN 105 and Gateway GPRS Support Node (GGSN)s 135A-B through core network 120. According to one embodiment of the invention, AAA device 300 communicates with core network 120. Core network 120 may be an IP packet based backbone network that includes routers, such as routers 125D-F, to connect the support nodes in the network. Routers are intermediary devices on a communications network that expedite message delivery. On a single network linking many computers through a mesh of possible connections, a router receives transmitted messages and forwards them to their correct destinations over available routes. Routers may be a simple computing device or a complex computing device. For example, a router may be a computer including memory, processors, and network interface units. GGSNs 135A-B are coupled to core network 120 through routers 125A-C and act as wireless gateways to data networks, such as network 140 and network 145. Networks 140 and 145 may be the public Internet or a private data network. GGSNs 135A-B allow MN 105 to access network 140 and network 145. Briefly described, AAA device 300 may be used to monitor and aid in carrying out the operator's control for the communication through ad hoc networks. AAA device 300 may be coupled core network 120 through communication mediums. AAA device 300 may be programmed by an operator with instructions to manage the policies relating to mobile network 100. AAA device 300 is an optional element. The operator may set threshold levels to determine whether or not to accept a new flow based on different service classes for a particular user or group of users. The routers, or a dedicated network element, such as AAA device 300, may be used for this purpose. Utilizing an AAA device helps to enforce authentication, authorization, and accounting rules to help ensure end-to-end quality of service (QoS) for users. Operators have the flexibility to provide different AAA rules. For example, conversational traffic may be mapped into either the Expedited Forwarding (EF) class or Assured Forwarding (AF) class at the core network. The operator may employ a different charging structure for each class. Also, AAA rules may be established nodes using different signaling transports. Furthermore, computers, and other related electronic devices may be connected to network 140 and network 145. The public Internet itself may be formed from a vast number of such interconnected networks, computers, and routers. Mobile network 100 may include many more components than those shown in FIG. 1. However, the components shown are sufficient to disclose an illustrative embodiment for practicing the present invention. The media used to transmit information in the communication links as described above illustrate one type of computer-readable media, namely communication media. Generally, computer-readable media includes any media that can be accessed by a computing device. Communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, communication media includes wired media such as twisted pair, coaxial cable, fiber optics, wave guides, and other wired media and wireless media such as acoustic, RF, infrared, and other wireless media. FIG. 2 shows another exemplary system in which the invention operates in which a number of local area networks (“LANs”) 220a-d, wireless local area networks 250A-C, and wide area network (“WAN”) 230 interconnected by routers 210. Optionally, AAA device 300 may be coupled to various places within the system to provide AAA services. On an interconnected set of LANs and WLANs—including those based on differing architectures and protocols—, a router acts as a link between LANs, enabling messages to be sent from one to another. Communication links within LANs typically include twisted wire pair, fiber optics, or coaxial cable, wherein communication links within WLANs include wireless links, while communication links between networks may utilize analog telephone lines, full or fractional dedicated digital lines including T1, T2, T3, and T4, Integrated Services Digital Networks (ISDNs), Digital Subscriber Lines (DSLs), wireless links, or other communications links. Furthermore, computers, such as remote computer 240, and other related electronic devices can be remotely connected to either LANs 220a-d or WAN 230 via a modem and temporary telephone link. The number of WANs, LANs, and routers in FIG. 2 may be increased or decreased without departing from the spirit or scope of this invention. As such, the Internet itself may be formed from a vast number of such interconnected networks, computers, and routers and that an embodiment of the invention could be practiced over the Internet without departing from the spirit and scope of the invention. It should be noted that instead of a WLAN (as defined in IEEE 802.11 standards), the WLAN in this example may represent any kind of a wireless local area network, i.e. such as Bluetooth wireless network. AAA device 300 may include program code that maintains the rules to charge and authorize the user for the ad hoc non-cellular connections set-up between terminals. Ad Hoc Networking of Terminals over Non-Cellular Interface Aided by a Cellular Network FIG. 3 shows exemplary ad hoc networking of terminals over a Non-Cellular interface aided by a cellular network, in accordance with aspects of the invention. For purposes of this discussion the non-cellular interface will be a WLAN access network. Again, this non-cellular interface can be provided by any kind of non-cellular access network without departing from the spirit of this invention. As shown in the figure, network 300 includes four domains; Internet 315, Cellular Core Network 320, Cellular Access Network 330, and WLAN Access Network 325. Terminals T1 340, T2 345, T3 350, T4 355, T5 360, and T6 365. WLAN Access Network 325 can be attached to the cellular network at different levels. As shown in the figure, terminals (T1-T6) are paired together (T1 and T2, T3 and T4, and T5 and T6) and show exemplary WLAN ad hoc links established (375, 380, and 385, respectively). Terminals T1, T2, and T3 use WLAN access network 325 for signaling. Terminals T4, T5, and T6 use cellular access network 330 for signaling. The signaling for the purpose of secure and easy non-cellular ad hoc link establishment is transported to the cellular network. For WLAN-only terminals or dual mode terminals currently associated with WLAN access, the signaling is transported over the WLAN access network (T1-T2). For dual-mode, WLAN and cellular, the signaling for the terminals can be transported either over the WLAN link to WLAN access network or cellular link to cellular access network (T3-T4, T5-T6). Both terminals do not have to use the same access network for the signaling. For example, terminal T3 and terminal T4 use different access networks. Terminal T3 uses WLAN access network 425 and terminal T4 uses cellular access network 430. The information transferred over the signaling link may include many different types of information. For example, the information may include user authentication, user ID retrieval (e.g., WLAN interface MAC address), security parameters, encryption keys and/or authorization and security association tokens allowing for secure WLAN ad hoc link establishment, radio resource management messages, and the like. A multi-hop ad hoc network may also be implemented where users' connection is established locally aided by each user's control connection to the infrastructure as described above. (See FIG. 4 and related discussion). To allow for an easy WLAN ad hoc link establishment, the peer's identifier is passed to the cellular network. The identifier could be the International Mobile Station Identity (IMSI) code (or equivalent) in WLAN terminal or in dual-mode terminal also in the non-WLAN part, user name (and operator), ISDN telephone number, network access identifier (NAI) or anything that can easily be communicated between users (verbal exchange of identities) or terminals (e.g., RF tags, identity broadcast over any medium, bar code, etc.). FIG. 4 illustrates a multi-hop signaling system that may be used in accordance with aspects of the invention. As illustrated in the figure, multi-hop signaling system 400 includes cellular infrastructure 405, terminal T1 (410), terminal T2 (415), terminal T3 (420), access links to cellular infrastructure 425 and 430, and WLAN ad hoc links 435, and 440. In order for some terminals to access the services provided by the cellular network, multi-hop signaling may be used. Terminals may not have direct access to the services provided by cellular infrastructure 405 for many reasons. For example, some terminals may only include a radio interface that is configured for a non-cellular network. Additionally, other terminals which are dual-mode terminals may be outside of the cellular network coverage. These dual-mode terminals, however, may be capable of connecting to a non-cellular network. Using the multi-hop signaling allows the terminals to reach the services provided by the cellular network according to this invention. As illustrated in the figure, terminal T3 (420) does not have direct access to cellular infrastructure 405. Terminal T3 may reach the services provided by cellular infrastructure, however, through terminal T2. Terminal T3 communicates with terminal T2 through WLAN ad hoc link (440). At some points in time, terminals T1 (410) and T2 (415) are directly connected to the services provided by cellular infrastructure 405 through links 425 and 430. At other points in time, however, terminals may be outside of the cellular network coverage. In this situation, a terminal, such as terminal T2 (415) may still have an ad hoc link. According to this particular example, terminal T2 maintains a WLAN ad hoc link (435) with terminal T1. As can be seen, this multi-hop signaling allows terminals to reach the services provided by the cellular network. FIG. 5 illustrates an operator controlled central register system, in accordance with aspects of the invention. As illustrated in the figure, central register system 500 includes mobile nodes T1 515, T2 520, T3 525, T4 530, and T5 535 and central register 510. Terminals T1, T2, T3 and T4 are arranged such that they may communicate with each other using a non-cellular link. Terminal T5, however, uses a cellular link in its communication with terminals T1, T2, T3, and T4. Mobile nodes, such as cellular phones, or PDA's with cellular cards, may utilize central register 510 operated a by an operator for organizing the ad hoc network and for routing the packets to a destination node. According to one embodiment of the invention, the mobile nodes in the network have both cellular (e.g. GPRS, GSM, UMTS) radio and non-cellular radio interfaces (e.g. Bluetooth, IR or WLAN). This operator may be the cellular operator for the users of the mobile node or a third party operator. The nodes in the ad hoc network have an option to use the operator-assisting service over the cellular radio, or try to manage without the service. According to one embodiment of the invention, the optional use of assistance is included in a routing algorithm in the nodes. When using the operator-assisted service, the nodes send regular update information of themselves over the cellular connection. The assisting service utilizes a standardized signaling scheme between the assisting servers and the mobile nodes. The standardized signaling scheme allows the nodes to communicate amongst themselves and the common operator. An advantage of the service is that the use of the service improves the quality of the ad hoc connection. Some of the services the operators may provide for the mobile nodes in the ad hoc network include: ad hoc network topology to assist in routing, service discovery, servers for ad hoc network applications like gaming or authentication, authorization and security functions, location related information, and the like. The scope of the service may be either micro-mobility within an ad hoc network link layer, in which case the macro-mobility in IP layer would be taken care by the mobile-IP, or both micro and macro-mobility, in which case it would be an alternative to mobile IP (Central Home agent operated by the operator). As mentioned above, the mobile nodes send information about their neighborhood to central register 510. For example, nodes within a Bluetooth neighborhood may send update information to central register 510 when the nodes realize there has been a change in their neighborhood. This change information of the neighborhood may include e.g. information of new Bluetooth, WLAN or other ad hoc connections to new mobile phones or information of loosing a Bluetooth, WLAN or other ad hoc connection to certain mobile phones. Sending of information may be done via the cellular connection, which may be for example a GPRS, GSM or UMTS connection, or some other connection. Based on the information received from the nodes by central register 510, central register 510 forms the description, or “the image” of the network. This description may be of any format suitable for describing the status and the layout of the network, especially the ad hoc parts of the network, which can then be used for determining the optimal route for each requested connection. More than one server may be used by the operator to perform the role of central register 510. According to this particular example, central register 510 will form a description of all Bluetooth, WLAN or other ad hoc connection capable nodes and their connections received from the mobile nodes (515, 520, 525, and 530). When using the services provided by the cellular network, the nodes communicate by first asking assistance from the cellular network, i.e. a central register as in this example. Depending on the service and QoS of the node, the central register returns an answer optimized for the node, which can be either a single/multi hop connection route to the destination or a recommendation to use the cellular connection. This answer may comprise one or more messages, which may be signaling or data messages. The operator (or other third party organization) may charge for the operator controlled service. These operator controlled ad hoc communication services can be used for any local communication applications like local voice-, messaging-, file transfer- or other data services. As a specific example, Local Multimedia Messaging enables the use of non-cellular radio (such as Bluetooth) in a multimode cellular media phone for local multimedia messaging communications. When sending a multimedia message from a media phone, the client software contacts cellular network, in example a central register (such as a server) in the operator's network to check, whether the receiver is in a few hop environment in the non-cellular ad hoc network, and if so, sends the message over the non-cellular radio, instead of the cellular network. The operator may, with a minimum investment, offer to users “free local multimedia messaging”. This attracts users to the network and the users would familiarize with the multimedia messaging by sending them at first mainly locally. Users may also use the multimedia messaging over a cellular connection. This increased volume of normal multimedia messaging is a major benefit for the operator. According to one embodiment of the invention, the pricing of the service is based on the amount of assistance required by the cellular network. This operator-assisted service consumes a negligible part of cellular network capacity (<5% of the multimedia messaging traffic). FIG. 6 illustrates a process for ad hoc networking of terminals over a non-cellular interface aided by a cellular network, in accordance with aspects of the invention. After a start block, the process moves to block 605, at which point the process determines the identities of the terminals desiring to establish an ad hoc link. Transitioning to block 610, the process determines the networks associated with the terminals. For example, a terminal may be coupled to a non-cellular network, a cellular network, or both. Moving to block 620, a signaling method is chosen for the terminals. The signaling method is related to the networks the terminal is coupled too. For example, non-cellular only terminals, the signaling is transported over a non-cellular access network. For dual-mode terminals that may communicate over non-cellular and cellular networks, the signaling may be transported either over the non-cellular link to non-cellular access network or cellular link to cellular access network. Both terminals do not have to use the same access network for the signaling. For example, one terminal could use a non-cellular access network and another terminal may use a cellular access network. Flowing to block 630, a secure connection is established between the terminals with the aid of the cellular network. The information transferred over the signaling link to cellular network may include many different types of information. For example, the information may include user authentication, user ID retrieval and mapping (e.g., WLAN interface MAC address from MSISDN or RF Tag's address), security parameters allowing for secure non-cellular ad hoc link establishment, radio resource management messages, and the like. Transitioning to block 640, once the secure connection is established and the network is aware of the ad hoc non-cellular connection, the rules may be enforced. For example, the users of the terminals may be charged based on the flow of information and data between the terminals using the ad hoc non-cellular connection. The process then steps to an end block and returns to processing other actions. The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. | <SOH> BACKGROUND OF THE INVENTION <EOH>The development of mobile communication devices and mobile networks has advanced at a rapid rate. At first, analog mobile networks enabled voice communication and simple paging features. Later, digital mobile networks provided more advanced features for voice and data communication, such as encryption, caller identification and short message service (SMS) text messages. More recently, third generation (3G) mobile IP network technology is being developed to enable users to easily access content rich media, information and entertainment with mobile devices. As networks advance, WLAN cellular networking is becoming an intensely discussed issue. Many see WLAN as an important component in the 3G evolution. For example, 3GPP is currently conducting feasibility studies on WLAN/UMTS interworking. The interest is not limited to 3GPP only but has also drawn attention at 3GPP2 and the Mobile Wireless Internet Forum (MWIF). Other evolution paths for interworking between cellular networks and ad hoc capable networks can be seen in e.g. Bluetooth, Infrared and Wireless Routing (WR). Exchanging data between two mobile terminals may be costly if conducted over the cellular infrastructure or if the terminals are co-located. Using a WLAN, Bluetooth or Infrared, or any other peer-to-peer interface for keeping a high rate (and possibly also volume) traffic local is efficient from a cost, bandwidth and spectrum usage point of view. Current WLAN, infrared (IR) and emerging Bluetooth/IEEE 802.15 (BT) standards would allow for the interface, but it is very difficult and clumsy to achieve a desired trusted security level between the terminals. Typically the connection set-up has would be done manually. Additionally, cellular operator revenue is lost when only using a WLAN/BT/IR/WR, or other non-cellular connection. A problem, however, is that current solutions offer limited functionality and usability. Current connection setup is standardized, e.g., for WLAN in IEEE 802.11b. What is needed is a way to establish secure links using cellular operator-controlled devices and a way for an operator to be involved in local traffic exchange that bypasses the infrastructure and thus offers a tool for additional revenue that would otherwise escape the operator. It is with respect to these considerations and others that the present invention has been made. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention is directed at addressing the above-mentioned shortcomings, disadvantages and problems, and will be understood by reading and studying the following specification. According to one aspect of the invention, mobile nodes equipped with a non-cellular wireless interface may establish a high data rate peer-to-peer ad hoc connection with the support of a cellular network. The cellular network may provide signaling for user authentication, peer identification, authentication key distribution for a secure non-cellular connection set-up, radio resources management messages, as well as charging and billing for the service. This is especially true, if one of the terminals is a server of music, games, streaming video, and the like. According to another aspect of the invention, the non-cellular link may be used for fast and secure ad hoc communication between the terminals. Signaling may be carried either over a non-cellular wireless access network or, using dual-mode terminals, over the cellular Radio Access Network (RAN). A combination of the signaling transport media is also possible. For example, one user may carry signaling over a WLAN RAN and the other user may carry signaling over a cellular system. According to yet another aspect of the invention, the cellular system is not limited to the Universal Mobile Telecommunications System (UMTS). Cellular network, as used in this application refers to any mobile network operated by an operator. For example, without limiting to these, the cellular network can be a GSM, GPRS, UMTS, using various radio access network technologies, such as CDMA2000, WCDMA and WLAN. Similarly, the non-cellular network and interface for the ad-hoc link may be any of the family of short range radios including BRAN Hiperlan, Hiperlan2, IEEE 802.11a, b, g, Multimedia Mobile Access Communication (MMAC) High-Speed Wireless Access (HISWA), Bluetooth, IEEE 802.15, and the like. The short range connection may even be a wired or infrared connection without departing from the spirit of this invention. According to a further aspect of the invention, a cellular infrastructure is used to identify and authenticate the mobile users, and deliver one or more encryption keys or tokens for a secure non-cellular link establishment. Number and kind of needed encryption keys or security association tokens is dependent on the security method(s) employed in the network, which is not a part of this invention. Any kind of suitable security method(s) can be employed in accordance to this invention. This eases the process and possibly generates additional revenue for an operator. For instance, the authentication and encryption (security) signaling services provided by the cellular network could be charged for. Another example for chargeable services can be routing assistance based on a dynamically updated register in the cellular network, which creates a description of the ad hoc network and provides optimized routing information for mobile nodes based on that description. Yet another example of such chargeable services is QoS (quality of service) support provided by the cellular infrastructure and supervised by the operator. In addition, if one of the terminals offers commercial services, this arrangement allows reusing the cellular billing infrastructure for charging for the service. According to still yet another aspect of the invention, a terminal is provided, which is able to communicate over ad hoc communication links with assistance provided from the cellular network for establishing the communication. The terminal receives information optimized for the terminal from the cellular network used in establishing communication links. According to a further aspect of the invention, a network node associated with cellular network for providing services associated with an ad hoc network can form descriptions of an ad hoc network for terminals associated with an ad hoc network. The network node receives requests for assistance from terminals for assistance in establishing a communication link. In response to the request, the network node provides an optimized answer to the terminal. The optimized answer may provide information relating to routing, quality enhancement, and security and authentication. According to one embodiment of the invention, the network node provides server or register functionality. | 20050114 | 20090811 | 20050714 | 91842.0 | 0 | MILLS, DONALD L | AD HOC NETWORKING OF TERMINALS AIDED BY A CELLULAR NETWORK | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,036,979 | ACCEPTED | Optical system, image projection apparatus and method thereof | An image projection apparatus. The image projection apparatus comprises a light source and LCD panel. The LCD panel comprises a plurality of pixels and color filters thereon. Light from the light source is projected to the pixels along an irradiative path and the LCD panel selectively reflects the projected light in accordance with an image signal along a projective path, wherein an angle between the irradiative and projective paths exceeds 0°. | 1. An optical system comprising: a light source providing light; a polarizer converting the light into polarized light; and a reflective liquid crystal light valve with a color filter; wherein the polarized light is projected to the reflective liquid crystal light valve along an irradiative path and reflected by the reflective liquid crystal light valve along a reflective path wherein an angle between the irradiative path and the projective path exceeds 0°. 2. The optical system of claim 1, further comprising an analyzer for polarizing the light from the reflective liquid crystal light valve. 3. The optical system of claim 1, further comprising a projection lens for projecting an image formed by the reflective liquid crystal light valve. 4. The optical system of claim 3, further comprising a screen for allowing the projection lens to project the image formed by the reflective liquid crystal light valve onto the screen. 5. The optical system of claim 1, wherein the reflective liquid crystal light valve is a liquid crystal on silicon (LCOS) panel. 6. An image projection apparatus comprising: a light source; a liquid crystal on silicon (LCOS) panel with a color filter; and a hologram disposed between the light source and the LCOS panel; wherein light from the light source is irradiated to the hologram along an irradiative path and therethrough to the LCOS panel, the LCOS panel then selectively reflecting the light to the hologram in accordance with an image signal and the light passing the hologram projecting along a projective path, such that an angle between the irradiative path and the projective path exceeds 0°. 7. The image projection apparatus of claim 6, wherein the irradiative path is perpendicular to the hologram, and thereby light is irradiated to the hologram at a 90° angle. 8. The image projection apparatus of claim 6, wherein the projective path is perpendicular to the hologram, and thereby light is projected by the hologram at a 90° angle. 9. The image projection apparatus of claim 6, wherein the hologram is holographic front diffuser or holographic lens. 10. The image projection apparatus of claim 6, wherein the color filter is selected from the group consisting of red, green, and blue color filters. 11. The image projection apparatus of claim 6, wherein the color filter is in mosaic-type, delta-type or PenTile-type arrangement. 12. The image projection apparatus of claim 6, further comprising: a polarizer disposed in the irradiative path; and an analyzer disposed in the projective path 13. The image projection apparatus of claim 12, further comprising: a condensing lens disposed in the irradiative path and between the polarizer and the light source; and a projection lens disposed in the projective path. 14. The image projection apparatus of claim 13, further comprising a screen disposed in the projective path, wherein the projection lens is disposed between the analyzer and the screen. 15. An image projection method comprising: irradiating light to a hologram along a irradiative path; irradiating light passing the hologram to a reflective liquid crystal light valve including a color filter; reflecting light irradiated to the liquid crystal light valve selectively to the hologram in accordance with an image signal; and projecting the light passing the hologram along a projective path, wherein an angle between the irradiative path and the projective path exceeds 0°. 16. The image projection method of claim 15, wherein the irradiative path is perpendicular to the hologram, and thereby light is irradiated to the hologram at a 90° angle. 17. The image projection method of claim 15, wherein the projective path is perpendicular to the hologram, and thereby light is projected by the hologram at a 90° angle. 18. The image projection method of claim 15, wherein the color filter is selected from the group consisting of red, green, and blue color filters. 19. The image projection method of claim 15, further comprising: polarizing the light irradiated to the hologram; and polarizing the light projected by the hologram. 20. The image projection method of claim 19, further comprising; focusing the light along the irradiative path before polarization; and projecting the light onto a screen by a projection lens in the projective path after the light is polarized. | BACKGROUND The invention relates to an optical system, and more particularly to an off-axis liquid crystal projector using a single chip. Reflective liquid crystal display (LCD) panels have many advantages over conventional transmissive LCD panels in many aspects. As a result, there has been an increasing trend to adopt reflective LCD panels in liquid crystal projectors. For example, the aperture ratio (i.e. the ratio of area between the actual size area of a pixel and the area of that pixel that can transmit light) of a transmissive LCD panel is limited, and it is necessary to add isolating material between pixels, which can generate pixilated images. For transmissive LCD panels, it is difficult to enable display devices having high resolution and high brightness at a reasonable production cost. Reflective LCD panels achieve desired aperture ratio and adopt specular material characterized by high reflectivity. Consequently, the reflective LCD panel addresses many of the problems of the transmissive LCD panel. FIG. 1 shows a conventional on-axis reflective projection system 100 comprising a light source 102, a polarizing beam splitter (PBS) 104, a color separator 106, a plurality of LCD panels 108, such as red, blue and green panels, and a projection lens 110. The light source 102 emits white light to the PBS 104. The PBS 104 only allows light of certain polarization therethrough and reflects light of other polarization to the color separator 106, according to a system axis 112. The color separator 106 then separates the red, blue and green components in the light and allows them to progress toward the respective red, blue and green LCD panels 108. Each LCD panel 108 is controlled by a system, such as a computer or other image source (not shown) and the reflected light from the pixels is selectively modulated to generate a light forming color image which is then reflected to the color separator 106. The color separator 106 combines incident red, green and blue light into a whole-color light and outputs it to the PBS 104 along system axis 112. PBS 104 allows only modulated light to pass to the projection lens 110, whereby the light is focused and projected onto a screen (not shown). Another on-axis reflective projection system adopts a single chip having color filters. This type of on-axis single chip projector requires no color separator or combining unit for the single chip having color filters, but there is still a need for PBS. The on-axis single chip projector, however, still has many unsolved problems. Firstly, light reflection efficiency is reduced by the single chip having color filters and the PBS in the light path. Secondly, if the incident angle of lights to the PBS increases, there is a serious drop in transmissivity. Thirdly, skew ray caused by the PBS also reduces contrast ratio (CR). In view of the above, the object of the invention is to provide an off-axis liquid crystal projector which does not require a PBS, eliminating conventional problems accordingly. According to one aspect of the invention, an optical system comprises a light source, a polarizer, and a reflective liquid crystal light valve with a color filter. The light source provides light to the polarizer, whereby most of the light is converted to polarized light. The polarized light is then projected to the reflective liquid crystal light valve along an irradiative path and reflected by the reflective liquid crystal light valve along a reflective path, wherein an angle between the irradiative and projective paths exceeds 0°. According to another aspect of the invention, an image projection apparatus comprises a light source, a liquid crystal on silicon (LCOS) panel with a color filter, and a hologram disposed between the light source and the LCOS panel. Light from the light source is irradiated to the hologram along an irradiative path and therethrough to the LCOS panel. The LCOS panel then selectively reflects the light to the hologram in accordance with an image signal and the light passing through the hologram is projected along a projective path, wherein there is an angle exceeding 0° between the irradiative and projective paths. According to another aspect of the invention, an image projection method is disclosed. The image projection method comprises irradiating light to a hologram along a irradiative path; irradiating light passing the hologram to a reflective liquid crystal light valve including a color filter; reflecting light irradiated to the liquid crystal light valve selectively to the hologram in accordance with an image signal; and projecting the light passing the hologram along a projective path, wherein an angle between the irradiative path and the projective path exceeds 0°. DESCRIPTION OF THE DRAWINGS The present invention is described by way of exemplary embodiments, but not limitations, illustrated in the accompanying drawings in which like references denote similar elements, and in which: FIG. 1 is a block diagram illustrating a conventional on-axis reflective projection system. FIG. 2 is a block diagram illustrating an off-axis reflective projector using a single chip according to an embodiment of the invention. FIG. 3 is a block diagram illustrating an off-axis reflective projector using a single chip according to another embodiment of the invention. FIG. 4 is a block diagram illustrating an off-axis reflective projector using a single chip according to another embodiment of the invention. FIG. 5 is a flowchart illustrating an image projection method according to an embodiment of the invention. DETAILED DESCRIPTION FIG. 2 shows an off-axis reflective projector 200 using a single chip 218 according to an embodiment of the invention. The projector 200 comprises a light source 210 emitting light through an opening 212 along an irradiative path (dotted line), a condensing lens 214, and a polarizer 216. The polarizer 216 permits only P-polarized light or S-polarized light to be projected onto a reflective LCD panel 218. The reflective LCD panel 218 reflects the light along a projective path (solid line) comprising an analyzer 220 and a projection lens 234 therein. The projective path terminates at a surface 240, such as a wall or a screen with an image determined by the reflective LCD panel 218 thereon. The LCD panel 218 comprises an Indium Tin oxide (ITO) glass substrate, a pixel substrate and liquid crystal therebetween. A plurality of pixels is arranged in a matrix alignment on the pixel substrate with a plurality of color filters thereon. The color filters can be, for example, red, blue or green and the arrangement thereof is mosaic-type, delta-type, PenTile-type or other. The LCD panel 218 is a liquid crystal light valve, such as a liquid crystal on silicon (LCOS) panel. The LCD panel 218 selectively reflects light irradiated to the pixels in accordance with an image signal which determines the rotation angle of liquid crystal in each pixel. For example, when the LCD panel 218 is in normal black mode, the pixel therein becomes a light pixel by increased voltage level between the glass and pixel substrates while a dark pixel without increasing the voltage level. The light source 210 can be a Cermax 500W xenon bulb or the like. The opening 212 is an input unit typically having an aperture ratio corresponding to the LCD panel 218. The condensing lens 214 is an ordinary lens or lens system converting light from light source 210, progressing toward the LCD panel 218 via the polarizer 216. The condensing lens 214 has magnification such that the magnified area of the opening 212 is approximately equal to or greater than the area of the LCD panel 218. The characteristic of the condensing lens 214 adopted depends on different designs and should be familiar to those skilled in the art. The light from the condensing lens 214 is projected to the LCD panel 218 via the polarizer 216. The polarizer 216 and analyzer 220 both purify polarization of light projected to the LCD panel 218 and reflected by the LCD panel 218, thereby improving the contrast of images with reduced scattered light. The polarizer 216 and analyzer 220 can be made of HN42HE polarizer manufactured by the Polaroid Corporation. Those skilled in the art will be familiar with other polarizers and analyzers to implement the described object of filtering the polarization of the reflected light from the LCD panel 218. As shown in FIG. 2, the analyzer 220 and polarizer 216 are parallel and face the LCD panel 218. There is both an angle in the irradiative and projective paths between the hypothetical axis perpendicular to the LCD panel 218. In a preferred embodiment, a normal of the surface on which the irradiative and projective paths travel is parallel to the normal of the FIG. 2 sheet. The angles of the two paths between the hypothetical axis are both 12° such that the angle between the two paths is 24°. FIG. 3 shows an off-axis reflective projector 300 using a single chip 218 according to another embodiment of the invention, units herein using the same reference numerals as those in FIG. 2 performing the same functions, and thus not described in further detail. The difference between FIG. 2 and FIG. 3 is that the off-axis reflective projector 300 further comprises a hologram 319 between the polarizer 216 and the LCD panel 218 and parallel to the LCD panel 218. The incident light perpendicular to the hologram 319 is irradiated to the LCD panel 218 at a right angle, thereby reflecting to the hologram 319 and then being diffracted by the hologram 319 in an oblique direction. Thus, angles in the irradiative and projective paths between the hypothetical axis perpendicular to the LCD panel 218 are smaller than those in FIG. 2, thus reducing size. The hologram 319 is a holographic front diffuser manufactured by Dupont or holographic lens. The holographic lens is made of Polycarbonate (PC) or Polymethylmethacrylate (PMMA). If the hologram 319 is a holographic front diffuser, it can be attached to the LCD panel 218 directly. FIG. 4 shows an off-axis reflective projector 400 using a single chip 218 according to still another embodiment of the invention, units herein using the same reference numerals as those in FIG. 2 performing the same functions, and thus not described in further detail. The difference between FIG. 2 and FIG. 4 is that the off-axis reflective projector 400 further comprises a hologram 419 between the polarizer 216 and LCD panel 218, and parallel to LCD panel 218. Incident light irradiated to the hologram 419 at an oblique angle is diffracted by the hologram 419 to the LC) panel 218 at a right angle, thereby being reflected and then irradiated by the hologram 419 at a right angle. Thus, the angles in the irradiative and projective paths between the hypothetical axis perpendicular to the LCD panel 218 are smaller than those in FIG. 2 while exceeding 0°. Size requirements for projectors are reduced because of the hologram 419. The hologram 419 can be a holographic front diffuser manufactured by Dupont or holographic lens. The holographic lens is made of Polycarbonate (PC) or Polymethylmethacrylate (PMMA). If the hologram 419 is a holographic front diffuser, it can be directly attached to the LCD panel 218. The difference between hologram 319 and hologram 419 is that hologram 319 allows light to be irradiated at a right angle. After reflected by the LCD panel 218 and diffracted by the hologram 319, light is irradiated obliquely. The hologram 419, however, allows light to be irradiated at an oblique angle. After diffracted by the hologram 419 to the LCD panel 218 at a right angle and reflected by the LCD panel 218, the light is projected by the hologram 419 at a right angle. FIG. 5 is a flowchart of an image projection method according to an embodiment of the invention. In step S51, a light source emits light through an opening along an irradiative path. In step S52, the light from the light source passes through a condensing lens, whereby light is generated along the irradiative path. In step S53, the light from the condensing lens passes a polarizer in the irradiative path, thereby polarized, such that most of the P-polarized light or S-polarized light passes the polarizer. In step S54, the light after polarization is projected to pixels in a LCD panel, covered by color filters. The LCD panel can be a liquid crystal on silicon (LCOS) panel. In step S55, the light projected to the pixels in the LCD panel is selectively reflected along a projective path in accordance with an image signal, with a 24° angle between the irradiative and projective paths. In step S56, light reflected by the LCD panel is polarized by an analyzer in the projective path and projected by a projection lens onto a screen. Thus, the invention provides an off-axis liquid crystal projector using a single chip, wherein the projective and irradiative paths are separated by an angle. Consequently, there is no need for a PBS, eliminating problems incurred thereby. While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. | <SOH> BACKGROUND <EOH>The invention relates to an optical system, and more particularly to an off-axis liquid crystal projector using a single chip. Reflective liquid crystal display (LCD) panels have many advantages over conventional transmissive LCD panels in many aspects. As a result, there has been an increasing trend to adopt reflective LCD panels in liquid crystal projectors. For example, the aperture ratio (i.e. the ratio of area between the actual size area of a pixel and the area of that pixel that can transmit light) of a transmissive LCD panel is limited, and it is necessary to add isolating material between pixels, which can generate pixilated images. For transmissive LCD panels, it is difficult to enable display devices having high resolution and high brightness at a reasonable production cost. Reflective LCD panels achieve desired aperture ratio and adopt specular material characterized by high reflectivity. Consequently, the reflective LCD panel addresses many of the problems of the transmissive LCD panel. FIG. 1 shows a conventional on-axis reflective projection system 100 comprising a light source 102 , a polarizing beam splitter (PBS) 104 , a color separator 106 , a plurality of LCD panels 108 , such as red, blue and green panels, and a projection lens 110 . The light source 102 emits white light to the PBS 104 . The PBS 104 only allows light of certain polarization therethrough and reflects light of other polarization to the color separator 106 , according to a system axis 112 . The color separator 106 then separates the red, blue and green components in the light and allows them to progress toward the respective red, blue and green LCD panels 108 . Each LCD panel 108 is controlled by a system, such as a computer or other image source (not shown) and the reflected light from the pixels is selectively modulated to generate a light forming color image which is then reflected to the color separator 106 . The color separator 106 combines incident red, green and blue light into a whole-color light and outputs it to the PBS 104 along system axis 112 . PBS 104 allows only modulated light to pass to the projection lens 110 , whereby the light is focused and projected onto a screen (not shown). Another on-axis reflective projection system adopts a single chip having color filters. This type of on-axis single chip projector requires no color separator or combining unit for the single chip having color filters, but there is still a need for PBS. The on-axis single chip projector, however, still has many unsolved problems. Firstly, light reflection efficiency is reduced by the single chip having color filters and the PBS in the light path. Secondly, if the incident angle of lights to the PBS increases, there is a serious drop in transmissivity. Thirdly, skew ray caused by the PBS also reduces contrast ratio (CR). In view of the above, the object of the invention is to provide an off-axis liquid crystal projector which does not require a PBS, eliminating conventional problems accordingly. According to one aspect of the invention, an optical system comprises a light source, a polarizer, and a reflective liquid crystal light valve with a color filter. The light source provides light to the polarizer, whereby most of the light is converted to polarized light. The polarized light is then projected to the reflective liquid crystal light valve along an irradiative path and reflected by the reflective liquid crystal light valve along a reflective path, wherein an angle between the irradiative and projective paths exceeds 0°. According to another aspect of the invention, an image projection apparatus comprises a light source, a liquid crystal on silicon (LCOS) panel with a color filter, and a hologram disposed between the light source and the LCOS panel. Light from the light source is irradiated to the hologram along an irradiative path and therethrough to the LCOS panel. The LCOS panel then selectively reflects the light to the hologram in accordance with an image signal and the light passing through the hologram is projected along a projective path, wherein there is an angle exceeding 0° between the irradiative and projective paths. According to another aspect of the invention, an image projection method is disclosed. The image projection method comprises irradiating light to a hologram along a irradiative path; irradiating light passing the hologram to a reflective liquid crystal light valve including a color filter; reflecting light irradiated to the liquid crystal light valve selectively to the hologram in accordance with an image signal; and projecting the light passing the hologram along a projective path, wherein an angle between the irradiative path and the projective path exceeds 0°. | 20050119 | 20080708 | 20050721 | 66963.0 | 0 | BLACKMAN, ROCHELLE ANN J | OPTICAL SYSTEM, IMAGE PROJECTION APPARATUS AND METHOD THEREOF | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,032 | ACCEPTED | Vehicle body having a tailgate system operable in a plurality of modes | A tailgate system for a dump body of a vehicle capable of operation in a plurality of modes includes a tailgate pivotally connected to side walls along an upper tailgate end for operation in a first mode and pivotally connected to one of the side walls along a tailgate side for operation in a second mode. A control assembly including a latching member, arm and handle is at least partially protected by placement within a corner post of the dump body. | 1. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; a tailgate pivotally connected to said side walls for operation in a first mode and pivotally connected to one of said side walls for operation in a second mode; corner posts attached to said sidewalls adjacent said tailgate; a latching member for engaging a pivot pin in the first mode and disengaging said pivot pin in the second mode; and an actuator for moving said latching member extending within one of said corner posts. 2. The body of claim 1, wherein said actuator is substantially enclosed within said one of said corner posts. 3. The body of claim 2, wherein said actuator is an arm connected to and extending between a handle and said latching member. 4. The body of claim 1, wherein said actuator is enclosed within said one of said corner posts. 5. The body of claim 4, wherein said actuator is an arm connected to and extending between a handle and said latching member. 6. The body of claim 1 further comprising a ball and socket for forming a pivotal connection along said one of said side walls in the second mode. 7. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; a tailgate having sides and upper and lower ends, said tailgate being pivotally connected along said upper tailgate end for operation in a first mode and pivotally connected along one of said tailgate sides for operation in a second mode; corner posts attached to said sidewalls adjacent said tailgate; a latching member for engaging a pivot pin along said upper tailgate end in the first mode; and an actuator extending within one of said corner posts for moving said latching member for disengaging said pivot pin in the second mode. 8. The body of claim 7, wherein said actuator is substantially enclosed within said one of said corner posts. 9. The body of claim 8, wherein said actuator is an arm connected to and extending between a handle and said latching member. 10. The body of claim 7, wherein said actuator is enclosed within said one of said corner posts. 11. The body of claim 10, wherein said actuator is an arm connected to and extending between a handle and said latching member. 12. The body of claim 7 further comprising a ball and socket for forming a pivotal connection along said one of said side walls in the second mode. 13. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; a tailgate pivotally connected to said side walls for operation in a first mode and pivotally connected to one of said side walls for operation in a second mode; corner posts attached to said sidewalls adjacent said tailgate; and control means positioned at least partially within one of said corner posts for selectively engaging a pivot pin in the first mode and disengaging said pivot pin in the second mode. 14. The body of claim 13, wherein said control means includes a latching member for securing said pivot pin in the first mode. 15. The body of claim 14, wherein said control means further includes a handle; and an arm connected to and extending between said handle and said latching member. 16. The body of claim 15, wherein said arm is substantially enclosed within said one of said corner posts. 17. The body of claim 15, wherein said arm is enclosed within said one of said corner posts. 18. The body of claim 13 further comprising a ball and socket for forming a pivotal connection along said one of said side walls in the second mode. 19. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; a tailgate rotatable around upper pivot pins in a first mode and pivotally connected along a tailgate side and rotatable thereabout in a second mode; corner posts attached to said sidewalls near said tailgate; a latching member for engaging one of said upper pivot pins in the first mode and disengaging said one of said upper pivot pins in the second mode; an actuator extending within one of said corner posts for moving said latching member; and a handle connected to said actuator for moving said actuator. 20. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; corner posts attached to said sidewalls adjacent said tailgate; a tailgate having sides and upper and lower ends, said tailgate rotatable around upper pivot pins extending beyond said tailgate sides along said tailgate upper end, and above said corner posts in a first mode and pivotally connected to one of said side walls along one of said tailgate sides for operation in a second mode; a latching member for engaging one of said upper pivot pins in the first mode and disengaging said one of said upper pivot pins in the second mode; an actuator connected to said latching member and extending within one of said corner posts for moving said latching member; and a handle connected to said actuator for moving said actuator, wherein said handle is in a raised position in the first mode and is rotated downward in the second mode thereby raising said actuator and a lower portion of said latching member causing said latching member to pivot thereby disengaging said one of said upper pivot pins. 21. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; corner posts attached to the body near said tailgate; a tailgate pivotally connected near said corner posts for operation in a first mode and pivotally connected to one of said side walls for operation in a second mode; an actuator extending within one of said corner posts for moving a latching member dependent upon operation in the first mode or the second mode. 22. The body of claim 21 further comprising a handle connected to said actuator, and wherein said handle is in a raised position in the first mode and is rotated downward in the second mode thereby raising said actuator. 23. A body for a vehicle having a tailgate operable in a plurality of modes comprising: a floor having a front wall and side walls attached thereto; corner posts attached to said sidewalls near said tailgate; a tailgate having sides and upper and lower ends, said tailgate rotatable around upper pivot pins supported adjacent said corner posts and extending beyond said tailgate sides for operation in a first mode and pivotally connected to one of said side walls along one of said tailgate sides for operation in a second mode; a latching member for engaging one of said upper pivot pins in the first mode and disengaging said one of said upper pivot pins in the second mode; an actuator connected to said latching member and extending within one of said corner posts for moving said latching member; and a handle connected to said actuator for moving said actuator. 24. The body of claim 23 wherein said handle is locked in a raised position in the first mode and is rotated downward in the second mode thereby raising said actuator and a lower portion of said latching member causing said latching member to pivot thereby lowering a blocking bar of said latching member thereby disengaging said one of said upper pivot pins. 25. The body of claim 24 further comprising a ball and socket for forming a pivotal connection along said one of said side walls in the second mode. | This application is a continuation of U.S. patent application Ser. No. 10/387,691, the disclosure of which is incorporated herein by reference. TECHNICAL FIELD The present invention relates generally to vehicle bodies having a tailgate system for dump trucks and dump trailers or the like, and capable of operation in a plurality of modes, and more specifically, to a ground control assembly for use therewith. BACKGROUND OF THE INVENTION Tailgates are generally known in combination with dump truck or dump trailer bodies (hereinafter referred to collectively as dump bodies). Conventional dump body tailgates are supported for pivotal movement during operation around upper pivot pins. More specifically, the tailgates rotate around upper pivot pins generally aligned with an upper end or top rail of the tailgate allowing a lower end of the tailgate to freely swing open as hauled materials are dumped from the dump body. This first mode of operation is referred to as a conventional dumping mode. In addition, it is known to disengage at least one of the pivot pins along the upper end of the tailgate to allow for rotation of the tailgate around one side thereof. This second mode of operation is referred to as a swing gate mode in which the tailgate of the dump body opens much like a typical barn door. One such prior art dump body capable of operation in a conventional and a swing gate mode of operation is Manufactured by Bibeau Enterprises, Inc. In the conventional mode of operation, a tailgate pivots around upper pivot pins. To transition the Bibeau dump body to the swing gate mode of operation, an operator must manually disengage the upper pivot pins through operation of a ground control assembly shown in FIG. 1, and manually engage a ball and socket assembly shown in FIG. 2 to provide a pivot point around which the tailgate will rotate. The ground control assembly, generally designated reference numeral 10, includes a lever 11 attached to an upwardly extending arm 12 which are externally positioned adjacent a rear corner post 13 of a dump body 14. The upwardly extending arm 12 in turn is attached to and controls a latching member 15. Operation of the lever 11 raises the upwardly extending arm 12 which in turn raises the latching member 15 causing the member to pivot and release one of the upper pivot pins 16. Although this ground control assembly 10 is adequate to perform its intended function of disengaging the upper pivot pin 16, the assembly stands off from the dump body sidewall making it prone to damage thru contact with other heavy equipment, hauled materials, and even tree limbs for example. In addition, the assembly is rather unsightly in contrast to the generally sleek lines of a dump body. Accordingly, a need is identified to protect such a ground control assembly from such contact type damage while maintaining the overall aesthetic appeal of the dump body. As shown in FIG. 2, the ball and socket assembly 18 of the Bibeau dump body includes a ball 19 supported by a mounting head 20 and a socket 21. The socket 21, shown in phantom for clarity, is designed for manual rotation through an angle of approximately forty-five degrees for engaging and disengaging the ball. The mounting head 20 is welded to a lower end of the tailgate 22 adjacent a rear corner post 23 of the dump body 14. A mounting shank 24 supporting the ball extends through the mounting head 20 and a nut 25 secures the ball 19 to the mounting head for movement with the lower portion of the tailgate 22 when the socket is disengaged. A pair of stub arms 26 welded to the rear corner post 23 of the dump body support the socket 21 for pivotal movement. The socket 21 is secured in engagement with the ball 19 by a collar 27 rotatably supported generally by the mounting head 20, and a locking pin 28 attached to the socket. In the swing gate mode, the collar 27 that is also shown in phantom for clarity is rotated into position directly beneath the ball 19. As the socket 21 is lowered into engagement with the ball 19, a shaft of the locking pin 28 extends through an aperture defined by the collar 27 and is secured in place with a cotter pin or the like. Once secured, upward rotation of the socket assembly is prevented by the collar contacting the ball. Again, although this ball and socket assembly form a suitable pivot point around which the tailgate can pivot in the swing gate mode, the assembly includes numerous pieces making it cumbersome for a vehicle operator to manipulate, and making manufacturing difficult. Perhaps more importantly, the assembly is only manually operable from a position adjacent the rear of the dump body. Accordingly, a further need is identified for an assembly which is simpler to operate and manufacture, and preferably which is operable from alongside the vehicle or from a cab of the vehicle. SUMMARY OF THE INVENTION In accordance with a first aspect of the present invention, a body for a vehicle including a tailgate system capable of operation in a plurality of modes is disclosed. The body comprises a floor having a front wall and side walls attached thereto, and a tailgate having sides and upper and lower ends. The tailgate may be pivotally connected to the side walls along the upper tailgate end for operation in a first or conventional mode, and pivotally connected to one of the side walls along one of the tailgate sides for operation in a second or swing gate mode. A socket may be attached to the tailgate for receiving and engaging a ball in the second mode of operation to form one of the pivotal connections along the tailgate side, and an actuator for moving the ball between a first disengaged position in the first mode of operation and a second engaged position in the second mode of operation may be provided. In one embodiment, the actuator may be a lever which may be locked in the second engaged position in the second mode of operation by a locking mechanism. The lever may extend through a corner post attached to the sidewalls adjacent the tailgate sides for actuating movement of at least one of the ball and socket. Alternatively, the actuator may be fluid operated. More specifically, a valve may be operatively connected between the actuator and a fluid reservoir for selectively moving the actuator between the first and second positions. A controller may be provided for selectively opening and closing the valve and may be positioned in a cab of the vehicle supporting the tailgate system or otherwise for convenient operation. In accordance with a second aspect of the present invention, a latching member for engaging one of the pivot pins along the upper tailgate end in the first mode of operation and disengaging the pivot pin in the second mode of operation may be provided. The latching member is moved between engaged and disengaged positions by a latching member actuator. The latching member actuator may be fluid operated wherein a fluid reservoir and a valve operatively connected between the actuator and the reservoir are provided. Alternatively, the latching member actuator may include a handle connected to an arm extending between the handle and the latching member. In accordance with another aspect of the present invention, at least part of the actuator may be enclosed within a corner post of the vehicle to prevent contact type damage thereto while still maintaining the sleek lines and overall aesthetic appeal of the dump body. As indicated above, the body supporting the tailgate system may be a dump truck including a cab or a dump trailer including a tractor for pulling the trailer and tailgate system. In accordance with another aspect of the present invention, a controller for selectively opening and closing the valve connected between the actuator and the reservoir may be positioned within the cab or tractor. In an alternate embodiment of the present invention, a body comprises a floor having a front wall and side walls attached thereto, and a tailgate having sides and upper and lower ends. The tailgate may be pivotally connected to the side walls along the upper tailgate end for operation in a first or conventional mode, and pivotally connected to one of the side walls along one of the tailgate sides for operation in a second or swing gate mode. A socket or ball may be attached to the tailgate for receiving and engaging a ball or socket, respectively, in the second mode of operation to form one of the pivotal connections along the tailgate side, and an actuator for moving the ball or socket between a first disengaged position in the first mode of operation and a second engaged position in the second mode of operation may be provided. In accordance with still another aspect of the present invention, a control means may be substantially positioned within a corner post attached to the sidewall adjacent the tailgate for selectively disengaging one of upper pivot pins in support of operation in the second mode. The control means may include a latching member for engaging one of the pivot pins along the upper tailgate end in the first mode of operation and disengaging the pivot pin in the second mode of operation. The latching member is moved between engaged and disengaged positions by a latching member actuator. The latching member actuator may be fluid operated wherein a fluid reservoir and a valve operatively connected between the actuator and the reservoir are provided. Alternatively, the latching member actuator may include a handle connected to an arm extending between the handle and the latching member. As indicated above, at least part of the actuator, handle, and arm may be enclosed within the vehicle corner post to prevent contact type damage thereto while still maintaining the sleek lines and overall aesthetic appeal of the dump body. In accordance with a method of the present invention, a dump body tailgate may be converted from a first or conventional mode of operation wherein the tailgate is pivotally connected to side walls along an upper tailgate end to a second or swing gate mode of operation wherein the tailgate is pivotally connected to one of the side walls along one of the tailgate sides. The method may include the steps of moving a ball from a first disengaged position for operation in the first mode of operation to a second position in engagement with a socket attached to the tailgate, and disengaging a pivot pin along the upper tailgate end. The method of converting the dump body tailgate, may further include actuating a lever attached to the ball and locking the lever in position once the ball and socket are engaged. The actuating step may further include opening a valve operatively connected between an actuator and a fluid reservoir to move the ball into engagement with the socket. In accordance with still another aspect of the method, the step of opening the valve may be performed from a cab of a vehicle supporting the dump body tailgate. The disengaging step of the present invention may include transitioning a latching member from a first position in engagement with the pivot pin to a second disengaged position by contacting the latching member with an arm. As indicated above, the arm may be enclosed within a corner post of the dumb body for engaging and disengaging the latching member. In addition, the step of moving may include actuating a lever attached to the ball. The following description shows and describes a preferred embodiment of this invention simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments, and its several details are capable of modifications in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings incorporated in and forming a part of the specification, illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings: FIG. 1 is a partial side elevational view of a ground control mechanism for releasing a pivot pin of a prior art dump body; FIG. 2 is a perspective view of a ball and socket assembly for creating a pivot point of a prior art dump body; FIG. 3 is a perspective view of dump body including a tailgate system for operation in a plurality of modes; FIG. 4 is a perspective view of a body including a tailgate and ground control assembly used to disengage an upper pivot pin to allow operation of the tailgate in the second mode; FIG. 5 is a cross-sectional view of an alternate ground control assembly positioned inside a rear corner post of the dump body; FIG. 6 is a perspective view of a ball and socket assembly of the body; FIG. 7 is a perspective view of a rear portion of a dump body showing a manual lever to move or pivot a lifting arm about a bushing in order to raise a ball into engagement with a socket for swing mode operation; and FIG. 8 is a cross-sectional side view showing movement of an alternate ball assembly between a disengaged position for operation in a conventional mode, and an engaged position for operation in a swing mode. Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. DETAILED DESCRIPTION OF THE INVENTION With reference to the perspective view of FIG. 3, there is shown a dump body 30 for a vehicle, i.e, dump truck or dump trailer, including a tailgate that is capable of operation in a plurality of modes. The body 30 includes a front wall 31 and side walls 32 attached to a floor 33, and a tailgate 34. In a first or conventional mode of operation, the tailgate 34 rotates around upper pivot pins 35 generally aligned with an upper end of the tailgate, and in a second or swing gate mode of operation, the tailgate rotates around a side of the tailgate. As best shown in FIG. 4, one of the upper pivot pins 35a in the present embodiment is temporarily engaged by a blocking bar 36 and the remaining upper pivot pin 35b is permanently engaged. In this manner, the tailgate 34 is allowed to pivot generally around its upper end during unloading in the conventional mode of operation. Lower pivot pins 37 are similarly provided that secure the lower end of the tailgate 34 together with the upper pivot pins 35 in a closed position during loading and travel of the dump body 30. In order to accommodate conversion between modes of operation, the dump body 30 of the present invention further includes a ground control assembly 38 and a ball and socket assembly 39. In accordance with the broad teaching of the present invention, the ground control assembly 38 may be positioned adjacent a rear corner post 40 of the dump body 30 as shown in FIG. 4 or substantially within the rear corner post as shown in FIG. 5. Since the ground control assembly 38 is substantially the same whether positioned adjacent to or within the rear corner post 40 of the dump body 30, only the ground control assembly positioned within the rear corner post will be described in detail at this time. As best shown in FIG. 5, the ground control assembly 38 generally includes a hand lever 41 linked to an upwardly extending arm 42. The upwardly extending arm 42 is attached at an upper end 43 to a latching member 44 for securing one of the upper pivot pins 35a in position during operation in the conventional mode, or during loading and travel of the dump body. Operation of the lever 41 (shown by action arrow A) raises the upwardly extending arm 42 which in turn raises a lower portion of the latching member 45 causing the member to pivot about pivot point P1. The upward movement of the lower portion of the latching member 45 and pivotal movement lower a blocking bar 46 of the latching member thus releasing one of the upper pivot pins 35a and freeing one side of the tailgate 34 to swing open. Referring back to FIGS. 3 and 4, lower pivot pins 37 extend from each side of the lower end of the tailgate 34 which are similarly engaged by lower latching members 47 during loading and travel of the dump body 30. During operation in either the conventional or swing gate mode, the lower pivot pins 37 are disengaged through operation of an air tailgate switch (not shown) as is well known in the art. The air tailgate or V8S switch is typically positioned in a cab of the vehicle. When activated, air pressure from an air tank positioned on a chassis of the dump body 30 is applied to a pneumatic cylinder causing the cylinder to stoke outwardly. The outward stroke and movement of the linkage operate to move or pivot the latching members 47 which disengage the latching members from the pivot pins 37. The arrangement of the latching members 47 and pivot pins 37 is best illustrated in FIG. 5. Although a similar pneumatic cylinder and linkage assembly are shown in FIG. 6, the air tailgate switch, pneumatic cylinder and linkage assembly arrangement which actuate the latching members 47 are well known in the art and are not shown herein. As shown in FIG. 1 and perhaps best shown in the perspective view of FIG. 6, a ball and socket assembly 39 of the dump body 30 includes a ball assembly 50 and a socket assembly 51. The ball assembly 50 includes a pivot bracket 52 welded to a rear corner post 53 of the dump body 30 (see FIG. 1). A bushing 54 is welded to the bracket 52 and provides a pivot point for lift arm 55. A mounting plate 56 is formed on or otherwise attached to the lift arm 55 and supports a ball 57 for movement between a disengaged position in the conventional mode of operation and an engaged position in the swing gate mode of operation. A mounting shank 58 supporting the ball 57 extends through the mounting plate 56 and a nut (not shown) secures the ball thereto. The mounting plate 56, the mounting shank 58, ball 57 and nut are supported by the dump body 30 and do not move with the lower portion of the tailgate 34 but independently about bushing 54. As best shown in FIG. 1, the socket assembly 51 is mounted to and moves with the tailgate 34. Referring back to FIG. 6, the socket assembly 51 includes a hitch plate 60 which supports a socket 61. A gusset 62 in the present embodiment provides additional strength to the socket assembly 51. It should be understood that the ball assembly and socket assembly may be mounted to the tailgate 34 and dump body 30 and actuated in any known manner in accordance with the broad teaching of the present invention. In the present embodiment, for example, the ball assembly 50 is attached to a pneumatic cylinder 63 mounted to the sidewall 32 of the dump body 30. The pneumatic cylinder 63 is attached to the lift arm 55 of ball assembly 50 via an appropriate linkage (not shown) and clevis 64. During unloading in the swing gate mode of operation, the lift arm 55 and ball 57 are raised into engagement with socket 61 through operation of the pneumatic cylinder 63. A second air switch, or V8S switch, is positioned in the cab of the dump truck or dump trailer in the present embodiment for activating the cylinder 63. When activated, air pressure from an air tank (not shown) positioned on the chassis of the dump body 30, for example, is applied to the pneumatic cylinder 63 causing the cylinder to stroke outwardly. The outward stroke and movement of the linkage and clevis 64 operate to move or pivot the lifting arm 55 about bushing 54 which raises the ball 57 into engagement with the socket assembly 51 and more specifically, the socket 61. The ball 57 is secured in the socket 61 until the air switch is deactivated by the operator in the cab. In an alternate embodiment of the present invention shown in FIG. 7, a lever 66 may be used to manually move or pivot the lifting arm 55 about bushing 54. Movement of the lever 66 similarly raises the ball 57 into engagement with the socket 61. In the present embodiment, the lever 66 is mounted just forward of the rear corner post 40 along a lower portion of the sidewall 32 of the dump body 30. Of course, other positions for the lever may be used in accordance with the present invention. In addition, a locking mechanism 67 is utilized in the present embodiment to prevent accidental operation of the lever 66. In another alternate embodiment of the present invention shown in FIG. 8, perhaps a simpler ball assembly 68 is described. The ball assembly 68 includes a mounting plate 69 welded to a rear corner post 70 of a dump body. The mounting plate 69 includes a pair of ears 71 which support a bushing 72. The bushing 72 provides a pivot point for lift arm 73. A mounting plate 74 is formed on or otherwise attached to the lift arm 73 and supports a ball 75 for movement between a disengaged position (shown in phantom lines) in the conventional mode of operation and an engaged position (shown in solid lines) in the swing gate mode of operation. A mounting shank 76 supporting the ball 75 extends through the mounting plate 74 and a nut 77 secures the ball thereto. As in the earlier described embodiment, the mounting plate 74, the mounting shank 76, ball 75 and nut 77 are all supported by the dump body sidewall and do not move with the lower portion of the tailgate 78 but independently about bushing 72. The socket assembly 79, on the other hand, includes a hitch plate 80 which supports a socket 81 and is mounted to and moves with the tailgate 78. This alternate ball assembly 68 may also be manually operated utilizing a lever or operated utilizing a pneumatic cylinder or the like as are described in detail above. To transition from the conventional mode of operation to the swing mode of operation, the ball and socket must be engaged. In one embodiment of the present invention, the operator activates a pneumatic cylinder from the cab of the dump body forcing the ball upwards into engagement with the socket. Once engaged, the tailgate may be opened in the swing mode by releasing the lower pivot points of the tailgate through activation of another pneumatic cylinder from the cab of the dump body or manually, and finally by disengaging an upper pivot pin utilizing the ground control assembly. The foregoing description of the present embodiments of the invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. For example, the ball assembly 50 may be mounted to and move with the tailgate 34. In such an alternate embodiment, the socket assembly 51 is supported by lift arm 55 for pivotal movement about bushing 54 between a disengaged position in the conventional mode of operation and an engaged position in the swing gate mode of operation. The present embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. | <SOH> BACKGROUND OF THE INVENTION <EOH>Tailgates are generally known in combination with dump truck or dump trailer bodies (hereinafter referred to collectively as dump bodies). Conventional dump body tailgates are supported for pivotal movement during operation around upper pivot pins. More specifically, the tailgates rotate around upper pivot pins generally aligned with an upper end or top rail of the tailgate allowing a lower end of the tailgate to freely swing open as hauled materials are dumped from the dump body. This first mode of operation is referred to as a conventional dumping mode. In addition, it is known to disengage at least one of the pivot pins along the upper end of the tailgate to allow for rotation of the tailgate around one side thereof. This second mode of operation is referred to as a swing gate mode in which the tailgate of the dump body opens much like a typical barn door. One such prior art dump body capable of operation in a conventional and a swing gate mode of operation is Manufactured by Bibeau Enterprises, Inc. In the conventional mode of operation, a tailgate pivots around upper pivot pins. To transition the Bibeau dump body to the swing gate mode of operation, an operator must manually disengage the upper pivot pins through operation of a ground control assembly shown in FIG. 1 , and manually engage a ball and socket assembly shown in FIG. 2 to provide a pivot point around which the tailgate will rotate. The ground control assembly, generally designated reference numeral 10 , includes a lever 11 attached to an upwardly extending arm 12 which are externally positioned adjacent a rear corner post 13 of a dump body 14 . The upwardly extending arm 12 in turn is attached to and controls a latching member 15 . Operation of the lever 11 raises the upwardly extending arm 12 which in turn raises the latching member 15 causing the member to pivot and release one of the upper pivot pins 16 . Although this ground control assembly 10 is adequate to perform its intended function of disengaging the upper pivot pin 16 , the assembly stands off from the dump body sidewall making it prone to damage thru contact with other heavy equipment, hauled materials, and even tree limbs for example. In addition, the assembly is rather unsightly in contrast to the generally sleek lines of a dump body. Accordingly, a need is identified to protect such a ground control assembly from such contact type damage while maintaining the overall aesthetic appeal of the dump body. As shown in FIG. 2 , the ball and socket assembly 18 of the Bibeau dump body includes a ball 19 supported by a mounting head 20 and a socket 21 . The socket 21 , shown in phantom for clarity, is designed for manual rotation through an angle of approximately forty-five degrees for engaging and disengaging the ball. The mounting head 20 is welded to a lower end of the tailgate 22 adjacent a rear corner post 23 of the dump body 14 . A mounting shank 24 supporting the ball extends through the mounting head 20 and a nut 25 secures the ball 19 to the mounting head for movement with the lower portion of the tailgate 22 when the socket is disengaged. A pair of stub arms 26 welded to the rear corner post 23 of the dump body support the socket 21 for pivotal movement. The socket 21 is secured in engagement with the ball 19 by a collar 27 rotatably supported generally by the mounting head 20 , and a locking pin 28 attached to the socket. In the swing gate mode, the collar 27 that is also shown in phantom for clarity is rotated into position directly beneath the ball 19 . As the socket 21 is lowered into engagement with the ball 19 , a shaft of the locking pin 28 extends through an aperture defined by the collar 27 and is secured in place with a cotter pin or the like. Once secured, upward rotation of the socket assembly is prevented by the collar contacting the ball. Again, although this ball and socket assembly form a suitable pivot point around which the tailgate can pivot in the swing gate mode, the assembly includes numerous pieces making it cumbersome for a vehicle operator to manipulate, and making manufacturing difficult. Perhaps more importantly, the assembly is only manually operable from a position adjacent the rear of the dump body. Accordingly, a further need is identified for an assembly which is simpler to operate and manufacture, and preferably which is operable from alongside the vehicle or from a cab of the vehicle. | <SOH> SUMMARY OF THE INVENTION <EOH>In accordance with a first aspect of the present invention, a body for a vehicle including a tailgate system capable of operation in a plurality of modes is disclosed. The body comprises a floor having a front wall and side walls attached thereto, and a tailgate having sides and upper and lower ends. The tailgate may be pivotally connected to the side walls along the upper tailgate end for operation in a first or conventional mode, and pivotally connected to one of the side walls along one of the tailgate sides for operation in a second or swing gate mode. A socket may be attached to the tailgate for receiving and engaging a ball in the second mode of operation to form one of the pivotal connections along the tailgate side, and an actuator for moving the ball between a first disengaged position in the first mode of operation and a second engaged position in the second mode of operation may be provided. In one embodiment, the actuator may be a lever which may be locked in the second engaged position in the second mode of operation by a locking mechanism. The lever may extend through a corner post attached to the sidewalls adjacent the tailgate sides for actuating movement of at least one of the ball and socket. Alternatively, the actuator may be fluid operated. More specifically, a valve may be operatively connected between the actuator and a fluid reservoir for selectively moving the actuator between the first and second positions. A controller may be provided for selectively opening and closing the valve and may be positioned in a cab of the vehicle supporting the tailgate system or otherwise for convenient operation. In accordance with a second aspect of the present invention, a latching member for engaging one of the pivot pins along the upper tailgate end in the first mode of operation and disengaging the pivot pin in the second mode of operation may be provided. The latching member is moved between engaged and disengaged positions by a latching member actuator. The latching member actuator may be fluid operated wherein a fluid reservoir and a valve operatively connected between the actuator and the reservoir are provided. Alternatively, the latching member actuator may include a handle connected to an arm extending between the handle and the latching member. In accordance with another aspect of the present invention, at least part of the actuator may be enclosed within a corner post of the vehicle to prevent contact type damage thereto while still maintaining the sleek lines and overall aesthetic appeal of the dump body. As indicated above, the body supporting the tailgate system may be a dump truck including a cab or a dump trailer including a tractor for pulling the trailer and tailgate system. In accordance with another aspect of the present invention, a controller for selectively opening and closing the valve connected between the actuator and the reservoir may be positioned within the cab or tractor. In an alternate embodiment of the present invention, a body comprises a floor having a front wall and side walls attached thereto, and a tailgate having sides and upper and lower ends. The tailgate may be pivotally connected to the side walls along the upper tailgate end for operation in a first or conventional mode, and pivotally connected to one of the side walls along one of the tailgate sides for operation in a second or swing gate mode. A socket or ball may be attached to the tailgate for receiving and engaging a ball or socket, respectively, in the second mode of operation to form one of the pivotal connections along the tailgate side, and an actuator for moving the ball or socket between a first disengaged position in the first mode of operation and a second engaged position in the second mode of operation may be provided. In accordance with still another aspect of the present invention, a control means may be substantially positioned within a corner post attached to the sidewall adjacent the tailgate for selectively disengaging one of upper pivot pins in support of operation in the second mode. The control means may include a latching member for engaging one of the pivot pins along the upper tailgate end in the first mode of operation and disengaging the pivot pin in the second mode of operation. The latching member is moved between engaged and disengaged positions by a latching member actuator. The latching member actuator may be fluid operated wherein a fluid reservoir and a valve operatively connected between the actuator and the reservoir are provided. Alternatively, the latching member actuator may include a handle connected to an arm extending between the handle and the latching member. As indicated above, at least part of the actuator, handle, and arm may be enclosed within the vehicle corner post to prevent contact type damage thereto while still maintaining the sleek lines and overall aesthetic appeal of the dump body. In accordance with a method of the present invention, a dump body tailgate may be converted from a first or conventional mode of operation wherein the tailgate is pivotally connected to side walls along an upper tailgate end to a second or swing gate mode of operation wherein the tailgate is pivotally connected to one of the side walls along one of the tailgate sides. The method may include the steps of moving a ball from a first disengaged position for operation in the first mode of operation to a second position in engagement with a socket attached to the tailgate, and disengaging a pivot pin along the upper tailgate end. The method of converting the dump body tailgate, may further include actuating a lever attached to the ball and locking the lever in position once the ball and socket are engaged. The actuating step may further include opening a valve operatively connected between an actuator and a fluid reservoir to move the ball into engagement with the socket. In accordance with still another aspect of the method, the step of opening the valve may be performed from a cab of a vehicle supporting the dump body tailgate. The disengaging step of the present invention may include transitioning a latching member from a first position in engagement with the pivot pin to a second disengaged position by contacting the latching member with an arm. As indicated above, the arm may be enclosed within a corner post of the dumb body for engaging and disengaging the latching member. In addition, the step of moving may include actuating a lever attached to the ball. The following description shows and describes a preferred embodiment of this invention simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments, and its several details are capable of modifications in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive. | 20050117 | 20070710 | 20050519 | 94390.0 | 2 | GORDON, STEPHEN T | VEHICLE BODY HAVING A TAILGATE SYSTEM OPERABLE IN A PLURALITY OF MODES | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,037,034 | ACCEPTED | System and method for vaporizing a cryogenic liquid | A system is provided for vaporizing a cryogenic liquid. The system includes means for producing an exhaust gas by flameless thermal oxidation of a fuel. The system also includes means for transferring heat from the exhaust gas to the cryogenic liquid. The heat transferring means is coupled to receive the exhaust gas from the exhaust gas producing means. The means for producing an exhaust gas optionally includes an oxidizer having a matrix bed, a fuel/air mixture inlet positioned to deliver the fuel/air mixture to the matrix bed, and an exhaust outlet positioned to deliver the exhaust gas from the oxidizer to the heat transferring means. The means for transferring heat optionally includes a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into the receptacle, and a sparger positioned to deliver exhaust gas from the exhaust gas producing means to the receptacle. | 1. A system for vaporizing a cryogenic liquid, said system comprising: means for producing an exhaust gas by flameless thermal oxidation of a fuel; and means for transferring heat from the exhaust gas to the cryogenic liquid, said heat transferring means being coupled to receive the exhaust gas from the exhaust gas producing means. 2. The system of claim 1, said means for producing an exhaust gas comprising an oxidizer having a matrix bed, a fuel/air mixture inlet positioned to deliver the fuel/air mixture to said matrix bed, and an exhaust outlet positioned to deliver the exhaust gas from said oxidizer to said heat transferring means. 3. The system of claim 1, said means for transferring heat comprising a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into said receptacle, and a sparger positioned to deliver exhaust gas from said exhaust gas producing means to said receptacle. 4. A system for vaporizing a cryogenic liquid, said system comprising: a flameless thermal oxidizer configured to generate an exhaust gas; a heat exchanger coupled to receive the exhaust gas from said flameless thermal oxidizer, said heat exchanger being configured to transfer heat from the exhaust gas to the cryogenic liquid. 5. The system of claim 4, said flameless thermal oxidizer comprising a matrix bed, a fuel/air mixture inlet positioned to deliver a fuel/air mixture to said matrix bed, and an exhaust outlet positioned to deliver exhaust gas from said oxidizer to said heat exchanger. 6. The system of claim 4, said heat exchanger comprising a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into said receptacle, and a sparger positioned to deliver exhaust gas from said flameless thermal oxidizer to said receptacle. 7. A method for vaporizing a cryogenic liquid, said method comprising the steps of: oxidizing a fuel in a flameless thermal oxidizer to produce an exhaust gas; and transferring heat from the exhaust gas to the cryogenic liquid, thereby vaporizing the cryogenic liquid. 8. The method of claim 7, said oxidizing step comprising delivering a fuel/air mixture into a matrix bed. 9. The method of claim 7, said transferring step comprising introducing exhaust gas into a heat transfer medium. 10. A method for providing a heat source to a vaporizer of cryogenic liquid, the method comprising the steps of: coupling a flameless thermal oxidizer to the vaporizer, and configuring the flameless thermal oxidizer to deliver exhaust gas to the vaporizer. 11. The method of claim 10, said coupling step comprising coupling an exhaust outlet of the flameless oxidizer to a sparger of the vaporizer. 12. A method for vaporizing a cryogenic liquid with reduced NOx emissions, said method comprising the steps of: oxidizing fuel using a flameless thermal oxidizer; transferring heat from exhaust gases generated by said oxidizing step to a cryogenic liquid. 13. The method of claim 12, further comprising the step of emitting less than about 5 ppmvd NOx, corrected to 3 volume percent oxygen (dry basis). 14. The method of claim 12, further comprising the step of emitting about 4 ppmvd NOx or less, corrected to 3 volume percent oxygen (dry basis). 15. The method of claim 12, further comprising the step of emitting about 2 ppmvd NOx or less, corrected to 3 volume percent oxygen (dry basis). 16. The method of claim 13, said emitting step being performed without catalytic treatment. 17. A flameless thermal oxidizer comprising: a matrix bed containing media; and an inlet tube extending into said matrix bed and having an outlet positioned to deliver reacting gases into said matrix bed; said matrix bed defining a void proximal said outlet of said inlet tube. 18. The flameless thermal oxidizer of claim 17, further comprising a disc positioned adjacent said outlet of said inlet tube and configured to direct reacting gases away from said inlet tube. 19. The flameless thermal oxidizer of claim 17, said void being substantially cyclindrical. 20. A method of reducing pressure losses in a flameless thermal oxidizer comprising introducing reacting gases from an inlet tube into a void defined by a matrix bed. | FIELD OF THE INVENTION This invention relates to a system and method for vaporizing a cryogenic liquid and, more particularly, a system for providing heat for cryogenic liquid vaporization. BACKGROUND OF THE INVENTION It is often necessary or desirable to vaporize a cryogenic liquid (i.e., to bring about vaporization of a cryogenic liquid to a vaporized state). For example, and though a wide variety of applications exist for liquid vaporization, it is often necessary or desirable to vaporize liquid natural gas (LNG) so that it can be handled and distributed as a fuel source. Many vaporization systems operate with burners in order to produce the necessary vaporization heat. For example, evaporators of the submerged combustion type comprise a water bath in which a flue gas tube of a gas burner is installed as well as an exchanger tube bundle for the vaporization of the liquefied gas. The gas burner discharges the combustion flue gases into the water bath, which heat the water and provide the heat for the vaporization of a liquefied gas that flows through the tube bundle. Such vaporization systems are provided, for example, by T-Thermal Company, a division of Selas Fluid Processing Corporation, under the registered trademark SUB-X. Evaporators of this type are reliable and of compact size, but they may become expensive to operate. For example, in order to reduce emissions of nitrogen oxide (NOx) from such systems, a current practice utilizes a gaseous fuel burner in combination with water injection to reduce NOx emissions. In such systems, NOx emissions can be reduced to approximately 30 ppmvd, corrected to 3 volume percent oxygen (dry basis). Further reduction of NOx emissions may require post combustion catalytic treatment. For example, a catalytic treatment system may be located at the outlet of a submerged liquid bath. Such treatment utilizes a portion of the burner exhaust to reheat the gases that are exiting the liquid bath, so as to reduce the moisture content of the gases before they enter the post combustion catalytic system. The corresponding use of this portion of the burner exhaust can, however, reduce the energy efficiency of the system, since this portion of the burner gases are not used to heat the cryogenic fluid. Accordingly, there remains a need for an improved method and system for cryogenic liquid vaporization. SUMMARY OF THE INVENTION According to one aspect of this invention, a system is provided for vaporizing a cryogenic liquid. The system includes means for producing an exhaust gas by flameless thermal oxidation of a fuel. The system also includes means for transferring heat from the exhaust gas to the cryogenic liquid. The heat transferring means is coupled to receive the exhaust gas from the exhaust gas producing means. The means for producing an exhaust gas optionally includes an oxidizer having a matrix bed, a fuel/air mixture inlet positioned to deliver the fuel/air mixture to the matrix bed, and an exhaust outlet positioned to deliver the exhaust gas from the oxidizer to the heat transferring means. The means for transferring heat optionally includes a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into the receptacle, and a sparger positioned to deliver exhaust gas from the exhaust gas producing means to the receptacle. According to another aspect of this invention, a method is provided for vaporizing a cryogenic liquid. The method includes oxidizing a fuel in a flameless thermal oxidizer to produce an exhaust gas. Heat is then transferred from the exhaust gas to the cryogenic liquid, thereby vaporizing the cryogenic liquid. The oxidizing step optionally includes delivering fuel/air mixture into a matrix bed, and the transferring step optionally includes introducing exhaust gas into a heat transfer medium. According to yet another aspect of this invention, a method provides a heat source to a vaporizer of cryogenic liquid. The method includes coupling a flameless thermal oxidizer to the vaporizer, and configuring the flameless thermal oxidizer to deliver exhaust gas to the vaporizer. The coupling step optionally includes coupling an exhaust outlet of the flameless oxidizer to a sparger of the vaporizer. According to still another aspect of this invention, a method is provided for vaporizing a cryogenic liquid with reduced NOx emissions. The method includes oxidizing fuel using a flameless thermal oxidizer, and transferring heat from exhaust gases generated by said oxidizing step to a cryogenic liquid. The method optionally includes emitting less than about 5 ppmvd NOx, emitting about 4 ppmvd NOx or less, or emitting about 2 ppmvd NOx or less, corrected to 3 volume percent oxygen (dry basis). Also, the method is optionally performed without catalytic treatment. According to another aspect, this invention provides a flameless thermal oxidizer having a matrix bed containing media, an inlet tube extending into the matrix bed and having an outlet positioned to deliver reacting gases into the matrix bed. The matrix bed defines a void proximal the outlet of the inlet tube. In the oxidizer, a disc is optionally positioned adjacent the outlet of the inlet tube and configured to direct reacting gases away from the inlet tube. The void defined in the matrix bed is optionally substantially cylindrical. According to another aspect, this invention provides a method of reducing pressure losses in a flameless thermal oxidizer, the method including introducing reacting gases from an inlet tube into a void defined by a matrix bed. BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the invention will be described with reference to several embodiments selected for illustration in the drawing, of which: FIG. 1 is a schematic, block diagram of a vaporization system according to one exemplary embodiment of this invention; FIG. 2 is a schematic diagram of an embodiment of a flameless thermal oxidizer capable of use in the vaporization system illustrated in FIG. 1; FIG. 3 is a schematic diagram of another embodiment of a flameless thermal oxidizer capable of use in the vaporization system illustrated in FIG. 1; FIG. 4 is a perspective view of yet another embodiment of a flameless thermal oxidizer capable of use in the vaporization system illustrated in FIG. 1; FIG. 5 is a perspective view of still another embodiment of a flameless thermal oxidizer capable of use in the vaporization system illustrated in FIG. 1; FIG. 6A is an elevation view of another embodiment of a vaporization system according to this invention; FIG. 6B is a plan view of the vaporization system illustrated in FIG. 6A; FIG. 6C is an elevation view of the vaporization system shown in FIG. 6A, with portions removed to reveal internal details; FIG. 7A is an elevation view of an embodiment of a manifold and distributor assembly capable of use in the vaporization system illustrated in FIG. 6A; FIG. 7B is an end view of the manifold and distributor assembly illustrated in FIG. 7A; FIG. 7C is a cross-sectional, end view of the manifold and distributor assembly illustrated in FIG. 7A; FIG. 7D is a plan view of a portion of the manifold and distributor assembly illustrated in FIG. 7A; FIG. 8A is an elevation view of an embodiment of a tube bundle assembly capable of use in the vaporization system illustrated in FIG. 6A; and FIG. 8B is a cross-sectional end view of the tube bundle assembly illustrated in FIG. 8A. DETAILED DESCRIPTION OF THE INVENTION The invention will next be illustrated with reference to the Figures. Such Figures are intended to be illustrative rather than limiting and are included herewith to facilitate explanation of the present invention. The Figures are not to scale, and are not intended to serve as engineering drawings. A flameless thermal oxidizer (FTO) has been coupled with a cryogenic heat exchanger according to one aspect of this invention to vaporize a liquid such as liquefied natural gas prior to injection into a utility distribution system. The resulting vaporization system minimizes oxides of nitrogen (NOx) emissions to the environment normally associated with conventional combustion processes. The thermal reaction of commercial fuel gas with air in a matrix bed of porous inert media is accomplished using the flameless thermal oxidizer. The reaction is optionally conducted in an apparatus that is capable of establishing and maintaining a non-planar reaction wave within the matrix bed. Generally, and according to one exemplary embodiment, the vaporization system includes a vessel that contains a matrix bed; one or more feed tubes that extend into the matrix bed; a burner or other matrix bed preheat system; connecting ductwork to a heat exchanger (such as the Sub-X® heat exchanger provided by T-Thermal Company of Blue Bell, Pa.); process controls; and an exhaust outlet to the atmosphere. A non-planar reaction wave (such as the one formed by the oxidizer shown in FIG. 3, for example) is established by heating at least a portion of the matrix bed to the minimum reaction temperature of a commercial fuel gas/air mixture and feeding said mixture at controlled rates into the feed tube(s). Upon exiting the feed tube(s), the commercial fuel gas/air mixture is reacted in a non-planar reaction wave to produce heat and non-toxic combustion products. The heat generated in the non-planar reaction wave maintains the interior surfaces of the vessel at a temperature of at least 1600 degree F. but less than 2400 degree F. during the entire operation, which minimizes the formation of NOx emissions. The hot exhaust gases are directed from the vessel through ductwork to a specialized cryogenic heat exchanger submerged in a water bath. Cryogenic liquids are directed through tubes in the interior of the heat exchanger as the quenched exhaust gases contact the exterior surfaces of the tubes via the water bath. The cryogenic fluid inside the heat exchanger completes a phase change to a gaseous product resulting from the flow of heated gases within the water bath. Exhaust gases exit the water bath and are released to the atmosphere via a stack. The natural gas vaporization capacity of the system ranges from about 150 to 200 million cubic feet per day, dependent on operating pressure conditions. Heat release rate for the flameless thermal oxidizer is 120 MMBtu/hr, and the emission rate of nitrogen oxides is reduced. The emissions of nitrogen oxides from the flameless oxidation process are approximately 2 ppmvd (corrected to 3 volume percent oxygen (dry basis)), which is significantly lower than the nitrogen oxide emissions from the burner exhaust of the current practice. The use of the flameless oxidation eliminates the need for water injection, as well as the post combustion catalytic NOx reduction treatment system. This elimination of the catalytic treatment system in turn eliminates the reoccurring use of both the catalyst and associated reducing agent (such as ammonia). Catalyst has a limited operating lifetime and is expensive to replace. The elimination of the reducing agent may make the system safer to operate by eliminating the storage and handling of ammonia. The elimination of the post catalytic treatment system along with the necessary heat input required to reheat the exhaust gases will increase the system energy efficiency by utilizing all of the flameless oxidation exhaust to heat the cryogenic fluid. Referring to the Figures generally, and according to one aspect of this invention, a system 1, 100 is provided for vaporizing a cryogenic liquid. To heat or vaporize fluids such as cryogenic liquids, the system 1, 100 utilizes flameless oxidation to provide the heat input into a submerged heat exchanger coil. The system 1, 100 includes means for producing an exhaust gas by flameless thermal oxidation of a fuel/air mixture. For example, the means for producing an exhaust gas optionally includes an oxidizer 2, 10, 40, 70, 108 having a matrix bed 29, 42, 72,112; a fuel/air mixture inlet 4, 54 positioned to deliver the fuel/air mixture to the matrix bed 29, 42, 72,112; and an exhaust outlet 5, 45, 78A, 78B, 114 positioned to deliver the exhaust gas from the oxidizer 2, 10, 40, 70, 108. The system 1, 100 also includes means for transferring heat from the exhaust gas to the cryogenic liquid. For example, the means for transferring heat optionally includes a vaporizer 3 having a receptacle 122 configured to hold a heat transfer medium; a conduit 118, 144 for cryogenic liquid extending into the receptacle; and a sparger 138 positioned to deliver exhaust gas from the exhaust gas producing means to the receptacle 122. The heat transferring means of the system 1, 100 is coupled to receive the exhaust gas from the exhaust gas producing means. In this manner, the products of reaction or oxidation in the exhaust gas producing means are delivered to the heat transferring means. Such heat transfer brings about vaporization of a cryogenic liquid. In use of system 1, 100, a fuel/air mixture is oxidized in a flameless thermal oxidizer 2, 10, 40, 70, 108 to produce an exhaust gas. Heat is then transferred from the exhaust gas to the cryogenic liquid, thereby vaporizing the cryogenic liquid. The oxidizing step optionally includes delivering fuel/air mixture into a matrix bed 29, 42, 72,112, and the transferring step optionally includes introducing exhaust gas into a heat transfer medium such as water. To modify or retrofit a vaporizer of cryogenic liquid according to one aspect of this invention, a flameless thermal oxidizer 2, 10, 40, 70, 108 is coupled to the vaporizer 3, and the flameless thermal oxidizer 2, 10, 40, 70, 108 is configured to deliver exhaust gas to the vaporizer 3. The coupling step optionally includes coupling an exhaust outlet 5, 45, 78A, 78B, 114 of the flameless oxidizer 2, 10, 40, 70, 108 to a sparger 138 of the vaporizer 3. To reduce NOx emissions according to another aspect of the invention, a fuel/air mixture is oxidized using a flameless thermal oxidizer 2, 10, 40, 70, 108, and heat from exhaust gases generated by the oxidizing step is transferred to a cryogenic liquid. The NOx emissions can be reduced to less than about 5 ppmvd NOx, preferably about 4 ppmvd NOx or less, or more preferably about 2 ppmvd NOx or less, corrected to 3 volume percent oxygen (dry basis). The reduction of NOx emissions is optionally performed without catalytic treatment. According to another aspect of this invention, a flameless thermal oxidizer 70 has a matrix bed 72 containing media, an inlet tube 80 extending into the matrix bed 72 and having an outlet positioned to deliver reacting gases into the matrix bed 72. The matrix bed 72 defines a void 73 proximal the outlet of the inlet tube 80. A disc 82 is optionally positioned adjacent the outlet of the inlet tube 80 and configured to direct reacting gases away from the inlet tube 80. The void 73 is optionally substantially cylindrical. To reduce pressure losses in a flameless thermal oxidizer, reacting gases can therefore be introduced from an inlet tube 80 into a void 73 defined by a matrix bed 72. Also, plural exhaust outlets 78A, 78B can be provided to exhaust reacted gases from the oxidizer 70. It has been discovered that this invention provides an efficient vaporization technology with very low oxides of nitrogen emissions (NOx) resulting from the combustion of natural gas fuel. For example, a typical burner system may operate with up to 40 percent excess air in a LNG vaporizer as compared to approximately 175 percent excess air with a flameless thermal oxidizer. Such excess air is beneficial in that it limits the maximum adiabatic temperature achieved in the oxidizer to less than the Zeldovich reaction mechanism requirements for high levels of NOx production. Fuel consumption is unchanged when the burner and flameless thermal oxidizer technologies are compared, but the volume of gases handled by the equipment is significantly larger for a flameless thermal oxidizer system according to this invention. A LNG vaporizer burner system together with water injection can produce NOx emissions in the range from 35 to 50 ppmvd. A LNG vaporizer using a flameless thermal oxidizer as the heat source according to this invention can produce NOx emissions in the range from 2 to 4 ppmvd, though NOx emissions lower than 2 ppmvd and greater than 4 ppmvd are contemplated as well (the foregoing NOx emissions values being corrected to 3 volume percent oxygen on a dry basis). In order to reduce NOx emissions (e.g., to comply with NOx emission regulations), burner systems typically use post-combustion treatment processes involving a catalyst and injection of a reducing agent chemical. These post-combustion control systems tend to be expensive, difficult to maintain, and require periodic shutdowns for catalyst cleaning and replacement. Referring specifically to the embodiments selected for illustration in the figures, FIG. 1 provides a schematic illustration of an embodiment of a vaporization system, generally indicated by the numeral 1, according to one aspect of this invention. Vaporization system 1 includes a flameless thermal oxidizer 2 that is coupled to a vaporizer 3. The flameless thermal oxidizer 2 is configured to receive a fuel/air mixture 4 for reaction within the flameless thermal oxidizer 2. Flameless thermal oxidizer 2 is also configured to deliver exhaust gases 5 that are produced as a result of the oxidation or reaction of the fuel/air mixture 4. The vaporizer 3 is configured to receive the exhaust gases 5 from the flameless thermal oxidizer 2. The vaporizer 3 is also configured to receive a cryogenic liquid 6 and to deliver a vaporized gas 7. Vaporizer 3 is also configured to deliver emissions 8. The hot exhaust gases 5 delivered from the flameless thermal oxidizer 2 to the vaporizer 3 causes vaporization of the cryogenic liquid 6 into a vaporized gas 7. Accordingly, the heat from exhaust gases 5 provides a heat source for the vaporization of the cryogenic liquid 6, and the exhaust gases 5 received in the vaporizer 3 from the flameless thermal oxidizer 2 are discharged from the vaporizer 3 in the form of emissions 8 either for further treatment or discharge to the atmosphere. FIG. 2 illustrates an exemplary embodiment of a flameless matrix bed reactor, generally designated by the numeral 10, which can be used in the vaporization system 1 illustrated in FIG. 1 as a component of the flameless thermal oxidizer 2. Referring to FIG. 2, there is shown a schematic of the internal temperature zones in a flameless matrix bed reactor 10 that contains a planar reaction wave 22. Additional details of the flameless matrix bed reactor 10 can be found in U.S. Pat. No. 6,015,540, which is incorporated herein by reference in its entirety. The flameless reactor 10 includes a vessel 25, having a matrix bed of porous inert media 29. The vessel is lined with a refractory material. Prior to the planar reaction wave, there is typically a cool zone 27 that has a temperature below the uniform reaction temperature. After the planar reaction wave 22, there will be a hot region 26 that is typically at least above 1200 degree F. By using temperature sensors 20, the planar reaction wave 22 may be located within the matrix and moved to a desired point by controlling the output end of a process controller 28. While this planar reaction wave temperature profile is effective for oxidation, corrosive products or reactants (such as acid gases or their pre-cursors) can tend to condense in the cool zone 27 on the interior surfaces 23 of the vessel 25. This condensation can occur when the corrosive products or reactants migrate through the lining of refractory material 24 adjacent to the interior surfaces 23 of the vessel 25. Additionally, if the vessel is constructed of heat resistant metal alloys, and there is no internal lining of refractory material, corrosive products or reactants can still condense on the interior surfaces of the vessel in the cool zone 27. This condensation in turn can lead to corrosion of the interior surfaces of the vessel. Consequently, the life of the vessel can be reduced and/or more expensive materials of construction may be needed to improve corrosion resistance FIG. 3 shows another embodiment of a flameless matrix bed reactor 40, which can be used to oxidize one or more chemicals. Additional details of the flameless matrix bed reactor 40 can be found in U.S. Pat. No. 6,015,540. Referring to FIG. 3, a flameless matrix bed reactor, generally designated by the numeral 40, is capable of use in the vaporization system 1 illustrated in FIG. 1 as a component of the flameless thermal oxidizer 2. As shown in FIG. 3, the flameless matrix bed reactor includes a vessel 41, containing a matrix bed 42 of porous inert media; a vessel refractory lining 63, located adjacent to the vessel interior surfaces 64; a feed tube 43 for receiving a reactable process stream 44, where a portion of the feed tube 43 that passes through the vessel is insulated with a refractory lining 62; an exhaust outlet 45 for removing reacted process stream 46; and a void space 47 located above the matrix bed 42. The matrix bed 42 is heated by introducing a heated medium (flue gases generated by a conventional fuel gas burner) 48, such as air, through a heating inlet 49. The reactable process stream is formed by combining in a mixing device 50 a fume stream 51 containing an oxidizable material, an optional oxidizing agent stream 52 (such as air or oxygen), and an optional supplementary fuel gas stream 53. After the reactable process stream is formed, it is fed into a feed inlet 54 of the feed tube 43. The reactable process stream is then directed to the exit 55 of the feed tube 43. A non-planar reaction wave 56 is established in the matrix bed located in a region approximately around the exit 55 of the feed tube 43 and the bottom 57 of the vessel. The reactable process stream 44 is reacted (in this embodiment oxidized) in the non-planar reaction wave 56 to produce the reacted process stream 46. The reacted process stream 46 is directed through the matrix bed 42, through the void space 47, and out the exhaust outlet 45. The exhaust outlet 45 is positioned so that the reacted process stream 46 prior to exiting the vessel 41 flows countercurrent to the flow direction in the feed tube 43. The exhaust outlet 45 may be connected to either the void space 47 or matrix bed 42. However, it is preferred that the exhaust outlet be connected to the void space 47. Temperature sensors 58 may be used for monitoring the temperature in the flameless matrix bed reactor 40. A process controller 59 may be used for accepting input from the temperature sensors 58 and, in response thereto, controlling the flow rate of the reactable process stream 44, the fume stream 51, the optional oxidizing agent stream 52, the optional supplementary fuel gas stream 53, and/or the heated medium 48 (e.g., flue gases generated by a conventional fuel gas burner). FIG. 4 shows a schematic, perspective view of a flameless thermal oxidizer, generally indicated by the numeral 70, that can be used as a component of the flameless thermal oxidizer 2 of the vaporization system 1 illustrated in FIG. 1. Flameless thermal oxidizer 70 includes a matrix bed 72 that extends upwardly to a top surface 74. The top surface 74 of the matrix bed 72 at least partially defines an oxidizer head space 76. Dual, opposed exhaust ducts 78A and 78B are positioned to exhaust reacted gases from the oxidizer head space 76. Specifically, reacted gases that enter the oxidizer head space 76 from the matrix bed 72 are delivered from the flameless thermal oxidizer 70 via exhaust ducts 78A and 78B. The provision of dual, opposed exhaust ducts such as ducts 78A and 78B has been discovered to reduce the pressure losses encountered by the flameless thermal oxidizer 70. Flameless thermal oxidizer 70 also includes a premixed gas dip tube 80 that extends downwardly into the matrix bed 72 in order to deliver a premix of gas into the matrix bed 72 at a location below the top surface 74 of the matrix bed 72. The dip tube 80 has a dip tube outlet diverter disc 82 positioned adjacent the outlet of the premixed gas dip tube 80. The disc 82 helps to divert reaction gases away from the wall of the dip tube. Referring now to FIG. 5, a modification to the flameless thermal oxidizer 70 illustrated in FIG. 4 is shown. Specifically, as illustrated in FIG. 5, the flameless thermal oxidizer 70 is provided with a modification to its matrix bed 72 in order to improve the performance of the flameless thermal oxidizer 70. A void is created in the ceramic media bed or matrix bed 72 just beneath the dip tube outlet so that gases can flow with less restriction into the matrix bed 72 to lower pressure losses in the flameless thermal oxidizer 70. The void is provided in the form of a cylindrical voidage 73. In one exemplary embodiment, the voidage 73 has a diameter of about 8 feet (corresponding roughly to the diameter of the dip tube outlet diverter disc 82) and a depth of about 3 feet. While the embodiment of the voidage 73 illustrated in FIG. 5 is substantially cylindrical in shape, it is contemplated that the voidage may have a wide variety of geometric shapes (e.g., spherical or semi spherical, elliptical, rectangular, or other geometric configurations). Referring now to FIGS. 6A and 6B, another embodiment of a vaporization system, generally indicated by the numeral 100, is illustrated. Vaporization system 100 includes a blower 102 configured to urge air into the vaporization system 100. Downstream from the blower 102 is a start-up burner 104 used during start-up of the vaporizer system 100 to preheat the matrix bed (described later). Also downstream from the blower 102 is a fuel-air mixer 106 configured to mix fuel with the air introduced by the blower 102. The vaporization system 100 also includes a flameless thermal oxidizer vessel 108 configured to receive the fuel-air mix provided by the fuel-air mixer 106. The flameless thermal oxidizer vessel 108 generates the heat that is used to vaporize liquid in the vaporization system 100. Specifically, hot gas is delivered from the flameless thermal oxidizer vessel 108 via a hot gas duct 114. From hot gas duct 114, hot gas is introduced into an SCV tank 122. Gases are then delivered from the SCV tank 122 by means of an exhaust separator 124 and an exhaust stack 126. FIG. 6C is another elevation view of the vaporization system 100, with wall portions removed to reveal internal details of the flameless thermal oxidizer vessel 108 and the SCV tank 122. The illustration in FIG. 6C also indicates the flow pattern of flue gases, indicated by arrows, in the flameless thermal oxidation vessel 108. The flameless thermal oxidation vessel 108 includes a dip tube 110 that extends downwardly into a ceramic packing 112. A mix of fuel and air is delivered through the dip tube 110 into the ceramic packing 112 for oxidation or reaction within the ceramic packing 112. The flue gases resulting from the reaction oxidation of the mixture of fuel and air travels upwardly through the ceramic packing 112 into a space above the ceramic packing 112 within the flameless thermal oxidation vessel 108, as indicated by the arrows in FIG. 6C. The flue gases are then urged outwardly from the flameless thermal oxidation vessel 108 and into the hot gas duct 114 for delivery to the SCV tank 122. The hot gas duct 114 is preferably insulated in order to reduce loss of heat from the flue gases. The SCV tank 122 is at least partially filled with a heat transfer medium such as water or other suitable medium. In operation, hot flue gases from the flameless thermal oxidizer vessel 108 are introduced into the heat transfer medium such that it bubbles through the heat transfer medium, heats the heat transfer medium, and brings about heat transfer from the heat transfer medium to cryogenic liquid flowing through a tubing bundle situated in the heat transfer medium. More specifically, the SCV tank 122 includes a manifold and distributor system such as assembly 116 connected to receive hot flue gases from the hot gas duct 114. Details of the manifold and distributor assembly will be described later with reference to FIGS. 7A-7D. The SCV tank 122 also includes a tube bundle 118 through which cryogenic liquid is circulated for vaporization. Further details of the tube bundle 118 will be described later with reference to FIGS. 8A and 8B. Liquid natural gas inlet and natural gas outlet manifolds are provided in the SCV tank 122 as indicated by numeral 120. It is by means of the inlet and outlet manifolds 120 that liquid natural gas is introduced into the tube bundle and the resulting natural gas is discharged from the tube bundle. Referring now to FIGS. 7A through 7D, details of an embodiment of a manifold and distributor assembly are illustrated. The manifold and distributor assembly, such as assembly 116, is configured to receive hot gases from the hot gas duct 114 and to deliver those hot gases into the heat transfer medium (e.g., water) in the SCV tank 122. More specifically, the manifold and distributor assembly 116 receives a stream of heated gas and divides that gas for substantially even distribution into the SCV tank to encourage heat transfer between the hot gases, the heat transfer medium, and ultimately the cryogenic liquid such as liquid natural gas circulating within the tube bundle 118. Referring specifically to FIG. 7A, the manifold and distributor assembly 116 includes a shell 128 that is substantially cylindrical in shape, though other cross-sectional shapes are contemplated as well. Shell 128 is coupled to the hot gas duct 114 by means of a flange 130. The opposite end of the shell 128 is capped by a plate 132. Plural lifting lugs 134 are provided along a top surface of the shell 128 in order to facilitate the handling of the shell 128 during assembly, disassembly, modification and/or maintenance. Plural supports 136 are provided to support the shell 128 against a foundation of the SCV tank 122 (not shown). In order to facilitate the distribution of hot gases from within the shell 128 to the heat transfer medium, the manifold and distributor assembly 116 is provided with plural spargers 138. Each sparger 138 extends outwardly from the shell 128 and is connected to the shell 128 in order to receive hot gases from the shell 128 and to deliver the hot gases to the heat transfer medium within the SCV tank 122. Referring to FIG. 7B, which provides an end view of the manifold and distributor assembly 116, the relationship between the sparger 138 and the shell 128 of the manifold and distributor assembly 116 can be seen. Specifically, each sparger 138 extends outwardly from a lower portion of the shell 128 at an angle substantially transverse to the axis of the shell 128. Referring to FIG. 7C, which provides a cross-sectional end view of the manifold and distributor assembly 116, each sparger 138 is provided with a closed end 140 and a plurality of openings 142 (generally positioned along its upper surface) to permit the flow of hot gases from within the sparger 138 to the heat transfer medium in the SCV tank 122. FIG. 7D provides a plan view of a portion of a sparger 138. Each sparger 138 includes plural rows of openings 142 (two such row shown in FIG. 7D). By means of openings 142, hot gas flows from within each sparger 138 and into the heat transfer medium in the SCV tank 122. While a specific embodiment of a manifold and distributor assembly 116 is shown in the Figures for purposes of illustration, a wide variety of configurations can be used in order to deliver hot gases to a heat transfer medium. Depending on a particular application or size constraints for a vaporization system, the manifold and distributor assembly can have a wide variety of shapes, sizes, and configurations. Preferably, however, the assembly will be configured to distribute hot gases substantially evenly into heat transfer medium so that heat can be substantially evenly distributed for the vaporization of cryogenic liquid. Referring now to FIGS. 8A and 8B, an exemplary embodiment of a tube bundle configured for use in the SCV tank 122 is illustrated. The tube bundle 144 illustrated in FIG. 8A includes four (4) tubes, each extending from an inlet 146 for liquid natural gas (or other cryogenic liquid) to an outlet 148 for vaporized natural gas (or other gas). The inlet 146 and outlet 148 of tube bundle 144 correspond to the inlet and outlet manifolds 120 illustrated in FIG. 6C. As illustrated in FIG. 8B, which provides a cross-sectional end view of tube bundle 144 (with the tubes removed for clarification), the inlet 146 and outlet 148 are provided with a plurality of openings for connection to tube bundles such as tube bundle 144. Accordingly, a plurality of tube bundles 144 are positioned next to each other and are connected for fluid flow communication with the inlet 146 and outlet 148 in order to provide a dense population of flow passages through which a cryogenic fluid can be passed for vaporization. For example, inlet 146 and outlet 148 can accommodate up to fifteen (15) or more tube bundles 144, each tube bundle 144 including four (4) tubes. In such an embodiment, the tube bundle assembly will provide sixty (60) tubes for the flow of cryogenic liquid such as liquid natural gas (LNG). Each tube bundle 144 can also have fewer or more than four tubes, and the tube bundle assembly can have fewer or more than fifteen (15) rows of tube bundles. EXAMPLE According to one aspect of this invention, a flameless thermal oxidizer can be modified to create a cylindrical void at the diptube outlet. Also, a flat disc can be added to the end of the diptube to direct reacting gases away from the diptube walls. These modifications were run on a CFD model and resulted in a significant reduction in pressure losses and also changed the shape of the reaction wave to force improved containment of the reaction gases within the ceramic media bed. The flameless thermal oxidizer was setup in the CFD model with a 60 inch ID by 20 foot long diptube. The ceramic media was simulated as 1 inch saddles, such as those used in commercial applications, packed to a depth of 16 feet. The diptube was simulated as being immersed 8 feet into the ceramic media bed. Two rectangular exhaust ducts were simulated to be used to convey flue gases from the surface of the ceramic media bed. The ducts were simulated to be installed 180 degrees apart in the headspace above the ceramic media bed. Dimensions for the ducts were simulated to be 2.5 feet high by 15 feet wide by 10 feet in length. The outlet of the diptube was simulated to be fitted with an 8 foot diameter disc to divert reaction gases away from the diptube wall. A void was simulated to be created in the ceramic media bed directly beneath the diptube outlet so that gases could flow with less restriction in an attempt to lower pressure losses in the flameless thermal oxidizer. The void was simulated to be a cylindrical volume 8 feet in diameter and 3 feet in height. The LNG vaporizer was simulated to exert a 60 inch water column back pressure on the heat source due to pressure losses in the heat exchanger tube bundle and water bath. Addition of the disc to the diptube outlet and the void constructed in the ceramic medial bed significantly reduced the pressure losses in the flameless thermal oxidizer. The reduction in pressure losses was simulated to be approximately 45 inches WC, yielding a total pressure loss across the flameless thermal oxidizer of only 17 inches WC. According to the simulation, the velocity of the premixed gases traveling down the diptube is approximately 50 feet per second. The total mass flow rate is approximately 4400 lbs/min yielding a heat release of 122 MMBtu/hr HHV. Combustion air is supplied at the rate of 4311 lbs./min and fuel gas at the rate of 86.26 lbs/min and, according to the simulation, the composition of the flue gases in volume percent is as follows: Component Volume Percent Oxygen 13.38 Nitrogen 76.54 Carbon Dioxide 3.32 Water Vapor 6.77 The gas velocity profile has been discovered to be significantly different in the ceramic bed with the optional cylindrical voidage beneath the diptube outlet, which contributes to a significant reduction in static pressure losses. Specifically, the temperature profile within the flameless thermal oxidizer after having installed the diptube exit disc and the voidage beneath the diptube differs from that of a flameless thermal oxidizer having ceramic media packing at the diptube discharge point and no disc attached to the diptube outlet. Also, it has been discovered that less carbon monoxide is present in the headspace above the ceramic media surface as compared to the unmodified oxidizer model. Although carbon monoxide burnout is achieved prior to the exhaust ducts in both designs, this feature is an improvement and lends more operational flexibility to the process. The CFD modeling results for a flameless thermal oxidizer with a diverter disc mounted on the discharge of the diptube and a cylindrical voidage located beneath the diptube discharge have indicated a significant reduction in static pressure losses across the oxidizer. This improvement benefits the operating economics for the flameless thermal oxidizer in the LNG vaporizer application. Pressure losses across the flameless oxidizer now amount to only 17 inches WC. Assuming that the pressure loss across the LNG vaporizer heat exchanger is not impacted by the flameless thermal oxidizer flue gas flow rate, then the total system pressure loss has been reduced from 122 inches WC to 77 inches WC. This represents a 37 percent reduction in pressure losses with the flameless thermal oxidizer modifications presented here. The pressure loss reduction across the flameless thermal oxidizer alone is a significant 72.6 percent with the modified design. The temperature profile indicates that the reaction wave is better confined to the ceramic media bed with the modified design. While it has been generally considered acceptable for there to be some cold gas breakout into the headspace without a loss in performance, the reaction wave should remain within the ceramic media bed in order to increase the robustness of the flameless thermal oxidizer and reduce any perception of loss in performance associated with cold gas breakout. Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. For example, the specific structures of the vaporizer and the flameless thermal oxidizer are not critical to the invention and may be modified within the scope of this invention. A wide variety of heat sources and heat exchangers can be utilized according to aspects of this invention. Similarly, the orientation of a heat exchanger (such as a vaporizer) with respect to the heat source (such as a flameless thermal oxidizer) can be modified to meet specific operating parameters. While preferred embodiments of the invention have been shown and described herein, it will be understood that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>It is often necessary or desirable to vaporize a cryogenic liquid (i.e., to bring about vaporization of a cryogenic liquid to a vaporized state). For example, and though a wide variety of applications exist for liquid vaporization, it is often necessary or desirable to vaporize liquid natural gas (LNG) so that it can be handled and distributed as a fuel source. Many vaporization systems operate with burners in order to produce the necessary vaporization heat. For example, evaporators of the submerged combustion type comprise a water bath in which a flue gas tube of a gas burner is installed as well as an exchanger tube bundle for the vaporization of the liquefied gas. The gas burner discharges the combustion flue gases into the water bath, which heat the water and provide the heat for the vaporization of a liquefied gas that flows through the tube bundle. Such vaporization systems are provided, for example, by T-Thermal Company, a division of Selas Fluid Processing Corporation, under the registered trademark SUB-X. Evaporators of this type are reliable and of compact size, but they may become expensive to operate. For example, in order to reduce emissions of nitrogen oxide (NOx) from such systems, a current practice utilizes a gaseous fuel burner in combination with water injection to reduce NOx emissions. In such systems, NOx emissions can be reduced to approximately 30 ppmvd, corrected to 3 volume percent oxygen (dry basis). Further reduction of NOx emissions may require post combustion catalytic treatment. For example, a catalytic treatment system may be located at the outlet of a submerged liquid bath. Such treatment utilizes a portion of the burner exhaust to reheat the gases that are exiting the liquid bath, so as to reduce the moisture content of the gases before they enter the post combustion catalytic system. The corresponding use of this portion of the burner exhaust can, however, reduce the energy efficiency of the system, since this portion of the burner gases are not used to heat the cryogenic fluid. Accordingly, there remains a need for an improved method and system for cryogenic liquid vaporization. | <SOH> SUMMARY OF THE INVENTION <EOH>According to one aspect of this invention, a system is provided for vaporizing a cryogenic liquid. The system includes means for producing an exhaust gas by flameless thermal oxidation of a fuel. The system also includes means for transferring heat from the exhaust gas to the cryogenic liquid. The heat transferring means is coupled to receive the exhaust gas from the exhaust gas producing means. The means for producing an exhaust gas optionally includes an oxidizer having a matrix bed, a fuel/air mixture inlet positioned to deliver the fuel/air mixture to the matrix bed, and an exhaust outlet positioned to deliver the exhaust gas from the oxidizer to the heat transferring means. The means for transferring heat optionally includes a receptacle configured to hold a heat transfer medium, a conduit for cryogenic liquid extending into the receptacle, and a sparger positioned to deliver exhaust gas from the exhaust gas producing means to the receptacle. According to another aspect of this invention, a method is provided for vaporizing a cryogenic liquid. The method includes oxidizing a fuel in a flameless thermal oxidizer to produce an exhaust gas. Heat is then transferred from the exhaust gas to the cryogenic liquid, thereby vaporizing the cryogenic liquid. The oxidizing step optionally includes delivering fuel/air mixture into a matrix bed, and the transferring step optionally includes introducing exhaust gas into a heat transfer medium. According to yet another aspect of this invention, a method provides a heat source to a vaporizer of cryogenic liquid. The method includes coupling a flameless thermal oxidizer to the vaporizer, and configuring the flameless thermal oxidizer to deliver exhaust gas to the vaporizer. The coupling step optionally includes coupling an exhaust outlet of the flameless oxidizer to a sparger of the vaporizer. According to still another aspect of this invention, a method is provided for vaporizing a cryogenic liquid with reduced NOx emissions. The method includes oxidizing fuel using a flameless thermal oxidizer, and transferring heat from exhaust gases generated by said oxidizing step to a cryogenic liquid. The method optionally includes emitting less than about 5 ppmvd NOx, emitting about 4 ppmvd NOx or less, or emitting about 2 ppmvd NOx or less, corrected to 3 volume percent oxygen (dry basis). Also, the method is optionally performed without catalytic treatment. According to another aspect, this invention provides a flameless thermal oxidizer having a matrix bed containing media, an inlet tube extending into the matrix bed and having an outlet positioned to deliver reacting gases into the matrix bed. The matrix bed defines a void proximal the outlet of the inlet tube. In the oxidizer, a disc is optionally positioned adjacent the outlet of the inlet tube and configured to direct reacting gases away from the inlet tube. The void defined in the matrix bed is optionally substantially cylindrical. According to another aspect, this invention provides a method of reducing pressure losses in a flameless thermal oxidizer, the method including introducing reacting gases from an inlet tube into a void defined by a matrix bed. | 20050118 | 20090602 | 20060817 | 92097.0 | F23D340 | 0 | DOERRLER, WILLIAM CHARLES | SYSTEM AND METHOD FOR VAPORIZING A CRYOGENIC LIQUID | UNDISCOUNTED | 0 | ACCEPTED | F23D | 2,005 |
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11,037,060 | ACCEPTED | Magnetic recording medium | A magnetic recording medium including a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having an intrinsic viscosity of from 0.47 to 0.51 dL/g, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa, and a breaking strength in the transverse direction of from 370 to 450 MPa. | 1. A magnetic recording medium comprising: a polymer support; and at least one magnetic layer containing a binder and one of a ferromagnetic metal powder having an average major-axis length of from 20 to 100 nm and a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm, wherein the polymer support has an intrinsic viscosity of from 0.47 to 0.51 dL/g, a Young's modulus in a machine direction of from 7.0 to 8.6 GPa, a Young's modulus in a transverse direction of from 5.4 to 8.0 GPa, and a breaking strength in the transverse direction of from 370 to 450 MPa. 2. The magnetic recording medium according to claim 1, wherein: the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least a first layer and a second layer; the first layer is provided at one side where the magnetic layer is formed, and has a first contact stylus three-dimensional surface roughness of from 1 to 6 nm; the second layer is provided at opposite side, and has a second contact stylus three-dimensional surface roughness of 6 to 10 nm; and the first contact stylus three-dimensional surface is smaller than the second contact stylus three-dimensional surface roughness. 3. The magnetic recording medium according to claim 1, wherein the intrinsic viscosity is from 0.47 to 0.50 dL/g. 4. The magnetic recording medium according to claim 1, wherein the Young's modulus in a machine direction is from 7.0 to 8.5 GPa, and the Young's modulus in a transverse direction is 5.6 to 7.8 Gpa. 5. The magnetic recording medium according to claim 2, wherein the first contact stylus three-dimensional surface is from 1.5 to 5.5 nm, and the second contact stylus three-dimensional surface roughness is from 6.5 to 9.0. 6. The magnetic recording medium according to claim 2, wherein the first layer contains a fine grain having an average diameter of from 30 to 150 nm at a ratio of not more than 0.1% by weight. 7. The magnetic recording medium according to claim 6, wherein the fine grain is selected from at least one of silica, calcium carbonate, alumina, a polyacrylic grain, and a polystyrene grain. 8. A magnetic recording medium comprising: a polymer support; and at least one magnetic layer containing a binder and one of a ferromagnetic metal powder having an average major-axis length of from 20 to 100 nm and a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm, wherein the polymer support has a number average molecular weight of from 12,000 to 18,000, a weight average molecular weight of from 32,000 to 40,000, a Young's modulus in a machine direction of from 7.0 to 8.6 GPa, and a Young's modulus in a transverse direction of from 5.4 to 8.0 GPa. 9. The magnetic recording medium according to claim 8, wherein: the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least a first layer and a second layer; the first layer is provided at one side where the magnetic layer is formed, and has a first contact stylus three-dimensional surface roughness of from 1 to 6 nm; the second layer is provided at opposite side, and has a second contact stylus three-dimensional surface roughness of 6 to 10 nm; and the first contact stylus three-dimensional surface is smaller than the second contact stylus three-dimensional surface roughness. 10. The magnetic recording medium according to claim 8, wherein the number average molecular weight is from 14,000 to 17,000, and the weight average molecular weight is from 33,000 to 38,000. 11. The magnetic recording medium according to claim 8, wherein the Young's modulus in a machine direction is from 7.0 to 8.5 GPa, and the Young's modulus in a transverse direction is 5.6 to 7.8 Gpa. 12. The magnetic recording medium according to claim 9, wherein the first contact stylus three-dimensional surface is from 1.5 to 5.5 nm, and the second contact stylus three-dimensional surface roughness is from 6.5 to 9.0. 13. The magnetic recording medium according to claim 9, wherein the second layer contains a fine grain having an average diameter of from 80 to 800 nm at a ratio of from 0.08 to 0.8% by weight. 14. The magnetic recording medium according to claim 13, wherein the fine grain is selected from at least one of calcium carbonate, silica, alumina, a polystyrene grain, and a silicone resin grain. | This application is based on Japanese Patent application JP 2004-023667, filed Jan. 30, 2004, the entire content of which is hereby incorporated by reference. BACKGROUND OF THE INVENTION 1. Technical Field of the Invention The present invention relates to a magnetic recording medium comprising a polymer support having thereon a magnetic layer containing a ferromagnetic powder and a binder and further to a magnetic recording medium having an excellent electromagnetic conversion characteristic and reliability. 2. Description of the Related Art In the magnetic recording field, putting digital recording which is small in deterioration of recording to practical use is developing in place of the conventional analog recording. In recording and reproducing equipment and magnetic recording media which are used in digital recording, not only high image quality and high sound quality, but also miniaturization and space reduction are required. However, in general, since much signal recording is necessary in the digital recording as compared with the analog recording, the digital recording is required to realize recording with a higher density. In recent years, a reproducing head applying magnetic resistance (MR) as an actuation principle was proposed and began to be used in a hard disc, etc. Also, JP-A-8-227517 proposes to apply the reproducing head to a magnetic tape. In an MR head, since a reproducing output of several times as compared with an induction type magnetic head is obtained and an induction coil is not used, by largely lowering noises of instruments such as an impedance noise to lower a noise of a magnetic recording medium, it becomes possible to obtain a large SN ratio. In other words, if the noise of the magnetic recording medium hidden in a conventional instrument is made small, good recording and reproduction can be achieved, and a high-density recording characteristic can be greatly improved. So far, in magnetic recording media, ones comprising a support having thereon a magnetic layer having Co-modified iron oxide, CrO2, a ferromagnetic metal powder, or a hexagonal ferrite powder dispersed in a binder are widely used. For the sake of reducing the noise, various measures may be considered. In particular, it is effective to decrease the size of a grain of the ferromagnetic powder. In recent magnetic materials, ferromagnetic metal fine powders having an average major axis length of not more than 100 nm are used, thereby enhancing the effect. In order to achieve the foregoing high-density recording, it is necessary to realize shorter the wavelength of a recording signal or to make the recording tracks narrow. For achieving this, in addition to realization of fine division of a ferromagnetic powder, high packing and ultra-smoothening of the surface of a magnetic recording medium, it is required to make a magnetic recording medium thin for the purpose of improving the volume density. In general, a coating type magnetic recording medium has a structure in which a magnetic layer is provided on a support, or a non-magnetic layer and a magnetic layer are provided in this order on a support. For the sake of making the foregoing magnetic recording medium thin, it is required to make not only the magnetic layer but also the whole of layers constructing the magnetic recording medium thin. For the purpose of making the thickness of the magnetic recording medium thin, it has hitherto been carried out to make the support thin or to make the non-magnetic layer thin. However, if the support is made thin exceeding a certain range, the running durability is lowered; and if the non-magnetic layer is made thin, a lowering of the output, an increase of the error rate, and an increase of the dropout are introduced. That is, if thinning of the magnetic recording medium advances for the purpose of increasing the recording density, a sufficient leveling effect against the support is not obtained in the magnetic layer, and the surface state of the support provided beneath the magnetic layer largely influences the surface of the magnetic layer. It may be considered that the principal cause resides in very small protrusions (so-called fish eyes) scattered on the surface of the support; the fish eyes become an anti-blocking filler, thereby lifting up the surface of the magnetic layer to form protrusions; and the dropout is generated due to these protrusions. In particular, in a linear recording system, since a magnetic tape runs substantially in parallel to a magnetic head and comes into contact with the head, the dropout caused due to protrusions present on the surface of the magnetic layer is liable to be generated. In order to prevent the dropout caused by the foregoing protrusions on the magnetic layer, it is necessary to change the filler contained in the support and smoothen the surface of the support. However, if the filler contained in the support is changed, the film formation step of a support, the production step of a magnetic recording medium, and the running properties within a drive after forming a tape are greatly influenced, and therefore, it cannot be said that this is an effective method. For this reason, a support having two or more layers in which the surface properties are made different between the side of the support at which a magnetic layer is provided and the side of the back surface against the former. Further, it is known that even if the support, especially the surface of the magnetic layer is smoothened, a stain is accumulated on the head, resulting in the occurrence of dropout. This is caused by the matter that an edge debris formed when an end face of the support is shaven by a running system within the drive is accumulated, and this end face is generated by slitting. Now, for the purpose of preventing a poor pancake shape from the occurrence by preventing a high edge of an end portion generated in the slitting step, JP-A-8-45060 describes a magnetic recording medium using a support made of polyethylene naphthalate having a thickness of 4 μm or more and regulated so as to have a ratio of the Young's modulus in the machine direction to the Young's modulus in the transverse direction of from 0.4 to 1.5 and a viscosity of from 0.45 to 0.53. The foregoing definition of the physical properties of the support is extremely broad and unclear. Also, only the foregoing definition is insufficient as a support for the recent magnetic recording media having an improved recording density. Since this JP-A-8-45060 discloses neither unit nor measurement method regarding the density, its invention is obscure. Also, with respect to the raw material of the support to be used, only the polyethylene naphthalate is described, but no description regarding its layer construction and surface properties is given. As described above, according to the conventional supports, it is difficult to provide a magnetic recording medium adapted for the recent demand of high recording density. SUMMARY OF THE INVENTION An object of the invention is to provide a magnetic recording medium which does not form an edge debris and can effectively prevent an increase of the error rate while meeting stable running properties. The means for solving the foregoing problems are as follows. (1) A magnetic recording medium comprising a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having an intrinsic viscosity of from 0.47 to 0.51 dL/g, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa, and a breaking strength in the transverse direction of from 370 to 450 MPa. (2) The magnetic recording medium as set forth above in (1), wherein the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least two layers, in which a contact stylus three-dimensional surface roughness SRa(A) of the surface (A surface) in the side at which the magnetic layer is provided is from 1 to 6 nm, and a contact stylus three-dimensional surface roughness SRa(B) of the back surface (B surface) against the A surface is from 6 to 10 nm, with SRa(A) and SRa(B) being satisfied with the relationship of [SRa(A)<SRa(B)]. (3) A magnetic recording medium comprising a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having a number average molecular weight (Mn) of from 12,000 to 18,000, a weight average molecular weight (Mw) of from 32,000 to 40,000, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, and a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa. (4) The magnetic recording medium as set forth above in (3), wherein the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least two layers, in which a contact stylus three-dimensional surface roughness SRa(A) of the surface (A surface) in the side at which the magnetic layer is provided is from 1 to 6 nm, and a contact stylus three-dimensional surface roughness SRa(B) of the back surface (B surface) against the A surface is from 6 to 10 nm, with SRa(A) and SRa(B) being satisfied with the relationship of [SRa(A)<SRa(B)]. The invention can provide a magnetic recording medium capable of keeping a good error rate without forming an edge debris by controlling the physical properties of a polymer support, i.e., an intrinsic viscosity or Mn and Mw and Young's moduli in the machine direction and transverse direction. DETAILED DESCRIPTION OF THE INVENITON The invention has been made based on the finding that a cause of forming an edge debris resides in the matter that when a magnetic recording medium is slit, if the Young's modulus or breaking strength of a polymer support is too high, a slitting blade excessively comes into the polymer support, thereby expanding an end face of the support. The breaking strength of the polymer support changes by the molecular weight (intrinsic viscosity) of a polymer to be used in the support, the stretching condition (Young's modulus) at the time of film formation, etc. The magnetic recording medium according to the first embodiment of the invention can improve the end face shape by slitting, i.e., the slitting properties, in its turn control the formation of an edge debris, and keep a good error rate by controlling the polymer support with respect to the intrinsic viscosity, the Young's moduli in the machine direction and transverse direction and the breaking strength in the transverse direction. The intrinsic viscosity as referred to in the invention means an intrinsic viscosity of the whole of a polymer material constituting the polymer support and means one determined by plotting a concentration of the polymer support (provided that insoluble solids such as a powder are eliminated) upon dissolution in a mixed solvent of phenol and 1,1,2,2-tetrachloroethane (weight ratio: 60/40) on the abscissa and plotting one obtained by measuring a relative viscosity corresponding to the solution at 25° C. using a Ubbelohde's viscometer on the ordinate and then extrapolating the point at which the concentration is 0. In the first embodiment of the invention, the intrinsic viscosity of the polymer support is from 0.47 to 0.51 dL/g, and preferably from 0.47 to 0.50 dL/g. By making the intrinsic viscosity fall within the foregoing range, not only the film forming properties and the strength are ensured, but also the slitting properties in the slitting step are kept good. When the intrinsic viscosity is less than 0.47 dL/g, the degree of polymerization is low so that the film forming properties and the strength are not increased. On the other hand, when it exceeds 0.51 dL/g, the slitting properties in the slitting are lowered. Also, the Young's modulus of the polymer support changes by the molecular weight of a polymer to be used in the support, the stretching condition at the time of film formation, etc. The magnetic recording medium according to the second embodiment of the invention can improve the end face shape by slitting, i.e., the slitting properties, in its turn control the formation of an edge debris, and keep a good error rate by controlling the polymer support with respect to the Mn and Mw and the Young's moduli in the machine direction and transverse direction. The terms “Mn” and “Mw” as referred to in the invention each means one determined from a calibration curve prepared by dissolving the polymer support in hexafluoroisopropnaol (HFIP) (provided that insoluble solids such as a powder are eliminated), charging this solution in GPC, HLC-8220 manufactured by Tosoh Corporation (column construction: Super HM-M×2, column vessel temperature: 40° C.), using the same HFIP as an eluting solution, and using polymethyl methacrylate (PMMA) having a known molecular weight. Incidentally, a polymer material constituting the polymer support may be any of one comprising repeating units having the same structure (inclusive of copolymers) as described later or one comprising repeating units having a different structure from each other. Therefore, the terms “Mn” and “Mw” as referred to in the invention do not mean only Mn and Mw of a polymer material comprising repeating units having the specific identical structure but are a concept including of all of polymer species constituting the polymer support. In the second embodiment of the invention, the Mn of the polymer support is from 12,000 to 18,000, and preferably from 14,000 to 17,000; and the Mw of the polymer support is from 32,000 to 40,000, and preferably 33,000 to 38,000. By making the Mn and Mw of the polymer support fall within the foregoing ranges, not only the film forming properties and the strength are ensured, but also the slitting properties in the slitting step are kept good. When the Mn is less than 12,000 or the Mw is less than 32,000, the degree of polymerization is low so that the film forming properties and the strength are not increased. On the other hand, when the Mn exceeds 18,000 or the Mw exceeds 40,000, the slitting properties in the slitting are lowered. In the invention, the Young's modulus and breaking strength of the polymer support are values measured by cutting the polymer support into specimen length and width of 100 mm and 5 mm, respectively and drawing the specimen at a rate of 100 mm/min under the circumference at 25° C. and 50% RH according to the method defined in JIS K7113 (1995). Incidentally, in the case where the Young's modulus in the machine direction (MD) is measured, the polymer support is cut such that the machine direction of the specimen length is in parallel to the machine direction of the polymer support; and in the case where the Young's modulus or breaking strength in the transverse direction (TD) is measured, the polymer support is cut such that the machine direction of the specimen length is in parallel to the transverse direction of the polymer support. Also, in the case where a sample only made of the polymer support, which is provided for the measurement, is not obtained, a polymer support obtained by peeling a layer from the magnetic recording medium may be used. In this case, in the case of where the magnetic recording medium is a magnetic tape, MD of the polymer support is coincident with MD of the magnetic tape; and in the case where the magnetic recording medium is a magnetic disc, the machine direction of stripes or scratches generated on the surface of the magnetic layer at the time of coating or calender treatment as observed upon observation of the surface of the magnetic layer by, for example, a differential interference microscope (power: from 50 to 200 times) is defined as MD of the polymer support, and the direction perpendicular thereto is defined as TD of the polymer support. In the first embodiment of the invention, the breaking strength of the polymer support is from 370 to 450 MPa, and preferably from 375 to 450 MPa. By making the breaking strength fall within the foregoing range, not only the film forming properties and the strength are ensured, but also the slitting properties in the slitting step are kept good. In the invention, the Young's modulus in the machine direction of the polymer support is from 7.0 to 8.6 GPa, and preferably from 7.0 to 8.5 GPa; and the Young's modulus in the transverse direction of the polymer support is from 5.4 to 8.0 GPa, and preferably from 5.6 to 7.8 GPa. By making the Young's moduli in the machine direction and transverse direction fall within the foregoing ranges, respectively, not only touch with a head is ensured, but also tape folding caused by guide pins of regulating the tape pass during running of the tape is prevented. In particular, when the Young's modulus in the machine direction exceeds 8.6 GPa, the touch with a head becomes insufficient; and when the Young's modulus in the transverse direction is less than 5.4 GPa, the tape is liable to cause folding by guide pins. Examples of the polymer support to be used in the invention include biaxially stretched polyethylene naphthalate, polyethylene terephthalate, polyamides (including aromatic polyamides), polyimides, polyamide-imides, and polybenzoxazole. Of these, polyesters comprising a dicarboxylic acid and a diol, such as polyethylene terephthalate and polyethylene naphthalate, are preferable. Examples of the dicarboxylic acid component as the principal constitutional component in the polyesters include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfonedicarboylic acid, diphenyl ether dicarboxylic acid, diphenylethanedicarboxylic acid, cyclohexanedicarboxylic acid, diphenyldicarboxylic acid, diphenylthioether dicarboxylic acid, diphenyl ketone dicarboxylic acid, and phenylindanedicarboxylic acid. Also, examples of the diol component in the polyesters include ethylene glycol, propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyethoxyphenyl)propane, bis(4-hydroxyphenyl)sulfone, bisphenol fluorene dihydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone, and cyclohexanediol. Of the polyesters comprising these compounds as the principal constitutional components, polyesters comprising, as the principal constitutional components, terephthalic acid and/or 2,6-naphthalenedicarboxylic acid as the dicarboxylic acid component and ethylene glycol and/or 1,4-cyclohexanedimethanol as the diol component are preferable from the standpoints of transparency, mechanical strength, dimensional stability, etc. Above all, polyesters comprising polyethylene terephthalate or polyethylene-2,6-naphthalate as the principal constitutional component, copolymer polyesters comprising terephthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol, and polyesters comprising a mixture of two or more kinds of these polyesters as the principal constitutional components are preferable; and polyesters comprising polyethylene-2,6-naphthalate as the principal constitutional component are especially preferable. The polyester which constitutes the biaxially stretched polyester film to be used in the invention may further be copolymerized with other copolymerization component or may be mixed with other polyester so far as the effect of the invention is not hindered. Examples thereof include the dicarboxylic components and diol components enumerated previously and polyesters comprising the same. For the purpose of hardly causing delamination at the time of film formation, the polyester to be used in the invention may be copolymerized with an aromatic dicarboxylic acid having a sulfonate group or an ester forming derivative thereof, a dicarboxylic acid having a polyoxyalkylene group or an ester forming derivative thereof, a diol having a polyoxyalkylene group, etc. Of these, 5-sodium sulfoisophthalate, 2-sodium sulfoterephthalate, 4-sodium sulfophthalate, and 4-sodium sulfo-2,6-naphthalene dicarboxylate; compounds resulting from substitution of the sodium of these compounds with other metal (for example, potassium and lithium), an ammonium salt, a phosphonium salt, etc. or ester forming derivatives thereof; and polyethylene glycol, polytetramethylene glycol, a polyethylene glycol-polypropylene glycol copolymer, and compounds resulting from conversion of a hydroxyl group at the both ends into a carboxyl group by oxidation, etc. are preferable from the standpoints of polymerization reactivity of the polyester and transparency of the film. A copolymerization proportion for this purpose is preferably from 0.1 to 10% by mole based on the dicarboxylic acid which constitutes the polyester. Also, for the purpose of enhancing the heat resistance, it is possible to copolymerize the polyester with a bisphenol based compound or a compound having a naphthalene ring or a cyclohexane ring. The copolymerization proportion thereof is preferably from 1 to 20% by mole based on the dicarboxylic acid which constitutes the polyester. The synthesis method of the polyester to be used in the invention is not particularly limited, but conventionally known production methods of polyesters can be employed. For example, a direct esterification method of directly esterifying the dicarboxylic acid component and the diol component; and an ester exchange method in which a dialkyl ester is first used as the dicarboxylic acid component and then subjected to ester exchange reaction with the diol component, and the reaction mixture is heated in vacuo to remove the excessive diol component, thereby achieving polymerization can be employed. In this case, if desired, an ester exchange catalyst or a polymerization reaction catalyst may be used, or a heat resistant stabilizer may be added. Also, one or two or more kinds of various additives such as a coloration preventive agent, an antioxidant, a crystal nucleating agent, a slipping agent, a stabilizer, a blocking preventive agent, an ultraviolet light absorber, a viscosity modifier, a defoaming clarifier, an antistatic agent, a pH modifier, a dye, a pigment, and a reaction stopping agent may be added in each of the steps at the time of the synthesis. These compounds may be used for the production of a polymer support made of other material than the polyester. In the synthesis of the polymer as a raw material of the polymer support to be used in the invention, the method of adjusting its intrinsic viscosity is not particularly limited. For example, the intrinsic viscosity can be adjusted by controlling the reaction time, reaction temperature, reaction solvent, pressure, concentration of starting monomer, catalyst, etc. in polymerizing the starting monomers. Also, in the synthesis, there is employable a method in which the reaction mixture is collected and measured for the viscosity corresponding to the advance of the reaction, and when the viscosity reaches a desired value, the reaction is stopped. Also, for example, there is employable a method in which correspondence of the intrinsic viscosity to a torque to be applied to a stirrer of a polymerization vessel is previously examined, and when the torque reaches a prescribed value, the reaction is stopped. Also, in the case of polycondensation reaction of, e.g., a polyester, there can be employed a method in which correspondence of the intrinsic viscosity to the amount of water (at the time of direct polymerization) or an alcohol (at the time of ester exchange reaction) to be discharged from the system at the time of polymerization is previously examined, and the polymerization reaction is stopped at the stage when a prescribed amount of water or the alcohol has been discharged. Also, there may be employed a method in which the polymerization is once carried out to an intrinsic viscosity exceeding the prescribed range, correspondence of the intrinsic viscosity to the melt viscosity is previously examined at the time of film formation, and the residence time of a polymer before and/or after melting within an extruder such that the melt viscosity falls within a prescribed range. These methods are merely enumerated as one example, and it should not be construed that the invention is limited to these methods. Further, as the polymer support in the invention, a contact stylus three-dimensional surface roughness SRa(A) of the surface (A surface) in the side at which the magnetic layer is provided is preferably from 1 to 6 nm, and more preferably from 1.5 to 5.5 nm. By making the SRa(A) fall within this range, when formed into a magnetic recording medium, not only the running durability is ensured, but also the output is kept high. As the polymer support in the invention, a contact stylus three-dimensional surface roughness SRa(B) of the back surface (B surface) of the surface (A surface) in the side at which the magnetic layer is provided is preferably from 6 to 10 nm, and more preferably from 6.5 to 9.0 nm. By making the SRa(B) fall within this range, not only a coefficient of friction of the B surface is kept low such that the handling properties of the film are ensured, but also a phenomenon in which in winding up the film having at least a magnetic layer in the rolled state, offset or shape transfer of the roughness of the B surface into the side of the A surface takes place, thereby roughing the side of the A surface is suppressed. The B surface may be as it is, or may be provided with a back layer. In the invention, the SRa(A) and SRa(B) mean values measured using a contact stylus three-dimensional surface roughness analyzer according to JIS B0601. As the polymer material capable of forming the A surface of the polymer support in the invention, ones which usually contain a fine grain usually having a mean grain size of from 30 to 150 nm, and preferably from 40 to 100 nm in an amount of not more than 0.1% by weight, and preferably not more than 0.06% by weight are desirable. From the standpoint of durability of the magnetic layer, it is desirable that the polymer material contains the foregoing fine grain. As this fine grain, silica, calcium carbonate, alumina, a polyacrylic grain, and a polystyrene grain are preferably used. Further, in the polymer support in the invention, what the B surface is rougher than the A surface is preferable from the standpoints of the film formation of a polymer support, the production step of a magnetic recording medium, and the running properties of a tape. The method of roughing the B surface is not particularly limited, but a method of mutually laminating two kinds of polymer layers which are different from each other with respect to the type, mean grain size and/or content of a fine grain is preferable. As the method of laminating polymer layers, a co-extrusion method is preferably employed. In this case, it is preferable that the thickness of the polymer layer for forming the B layer is from ½ to 1/10 of the thickness of the whole film. Examples of the fine grain to be used in the polymer layer for forming the B surface include calcium carbonate, silica, alumina, a polystyrene grain, and a silicone resin grain. The mean grain size is preferably from 80 to 800 nm, and more preferably from 100 to 700 nm. The addition amount is preferably from 0.05 to 1.0% by weight, and more preferably from 0.08 to 0.8% by weight. The laminated polymer support in the invention is a laminated polyester film and can be produced according to conventionally known methods. For example, using a known extruders a polymer material for forming the A surface and a polymer material for forming the B surface are laminated within a die, the laminate is extruded into a sheet-like form from a nozzle at a temperature of the melting point (Tm) to (Tm+70° C.), and the extruded laminate is quenched for solidification at from 40 to 90° C. to obtain a laminated unstretched film. Thereafter, the unstretched film is stretched in the uniaxial direction at a stretching ratio of from 2.5 to 4.5 times, and preferably from 2.8 to 3.9 times at a temperature in the vicinity of from {[glass transition temperature (Tg)]−10} to (Tg+70)° C. and then stretched in the perpendicular direction to the former at a stretching ratio of from 4.5 to 8.0 times, and preferably from 4.5 to 6.0 times at a temperature in the vicinity of from Tg to (Tg+70)° C., and if desired, the stretched film is again stretched in the machine direction and/or the transverse direction to obtain a biaxially oriented film according to the customary manner. That is, the stretching may be carried out at two stages, three stages, four stages, or multiple stages. The total stretching ratio is usually 12 times or more, preferably from 12 to 32 times, and more preferably from 14 to 26 times in terms of area stretching ratio. Further, the biaxially oriented film is subsequently subjected to heat fixing and crystallization at a temperature of from (Tg+70) to (Tm−10)° C., for example, from 180 to 250° C., thereby imparting excellent dimensional stability. Incidentally, the heat fixing time is preferably from 1 to 60 seconds. It is preferred to adjust the rate of heat shrinkage by relaxation at a rate of not more than 3.0%, and preferably from 0.5 to 2.0% in the machine direction and/or the transverse direction by this heat fixing treatment. Even in the case where the polymer support in the invention is a single layer, it should be clear that the polymer support can be produced according to the foregoing production method of a laminated polymer support. In the magnetic recording medium in the invention, a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm is used as the ferromagnetic metal powder to be contained in the magnetic layer. It is known that this ferromagnetic metal powder is excellent with respect to the high-density magnetic recording characteristic, and a magnetic recording medium having an excellent electromagnetic conversion characteristic can be obtained. While the average major axis length of the ferromagnetic metal powder to be used in the magnetic layer of the magnetic recording medium of the invention is from 20 to 100 nm, it is preferably from 30 to 90 nm, and more preferably from 40 to 80 nm. When the average major axis length of the ferromagnetic metal powder is 20 nm or more, a lowering of the magnetic characteristic can be effectively suppressed due to thermal fluctuation. Also, when the average major axis length is not more than 100 nm, good C/N (S/N) can be obtained while keeping a low noise. The average major axis length of the ferromagnetic metal powder can be determined from a mean value of values measured by a combination of a method in which the ferromagnetic metal powder is photographed by transmission electron microscopic photography and a minor axis length and a major axis length of the ferromagnetic metal power are directly read from the photograph and a method in which the transmission electron microscopic photograph is traced and read by an image analyzer IBASSI, manufactured by Carl Zeiss AG. Next, the layer construction of the magnetic recording medium of the invention will be described below. So far as the magnetic recording medium of the invention has at least one magnetic layer on at least one surface of the polymer support, its layer construction is not particularly limited. For example, a non-magnetic layer may be provided between the polymer support and the magnetic layer. Also, if desired, a back layer may be provided on the surface opposite to the side of the polymer support. Also, the magnetic recording medium of the invention may be provided with a lubricant coating film or a variety of coating films for protecting the magnetic layer on the magnetic layer as the need arises. Also, it is possible to provide an undercoat layer (easily adhesive layer) between the polymer support and the magnetic layer or non-magnetic layer for the purposes of improving the adhesion between the coating film and the polymer support. In the magnetic recording medium of the invention, the magnetic layer may be provided on either one surface of the polymer support but can be provided on the both surfaces thereof. In the construction comprising the non-magnetic layer (lower layer) and the magnetic layer (upper layer), after coating the lower layer, the magnetic layer as the upper layer can be provided in any of the state wherein the lower layer is wet (W/W) or the state wherein the lower layer is dry (W/D). From the standpoint of productivity, simultaneous or sequential wet coating is preferable. In the multilayered construction of the invention, since the upper layer/lower layer can be simultaneously formed by simultaneous or sequential wet coating (W/W), a surface treatment step such as a calender step can be effectively applied, and even in an ultra-thin layer, the surface roughness of the magnetic layer as the upper layer can be improved. The constructional elements of the magnetic recording medium of the invention will be described below in more detail. [Magnetic Layer] <Ferromagnetic Metal Powder> The ferromagnetic metal powder to be used in the magnetic layer in the magnetic recording medium of the invention is not particularly limited so far it contains Fe as the major component (inclusive of alloys) but is preferably a ferromagnetic alloy powder containing α-Fe as the major component. Such a ferromagnetic metal powder may contain atoms such as Al, Si, S, Sc, Ca, Ti, V, Cr, Cu, Y, Mo, Rh, Pd, Ag, Sn, Sb, Te, Ba, Ta, X, Re, Au, Hg, Pb, Bi, La, Ce, Pr, Nd, P, Co, Mn, Zn, Ni, Sr, and B in addition to the prescribed atoms. Of these, ones containing at least one of Al, Si, Ca, Y, Ba, La, Nd, Co, Ni, and B in addition to α-Fe are preferable; and ones containing Co, Al and Y are especially preferable. More specifically, ones containing from 10 to 50 atomic % of Co, from 2 to 20 atomic % of Al, and from 1 to 15 atomic % of Y based on Fe are preferable. The foregoing ferromagnetic metal powder may be previously treated with a dispersant, a wetting agent, a surfactant, an antistatic agent, etc. as describe later. Also, the ferromagnetic metal powder may contain a small amount of water, a hydroxide or an oxide. The water content of the ferromagnetic metal powder is preferably from 0.01 to 2%. It is preferred to optimize the water content of the ferromagnetic metal powder depending upon the type of a binder. It is preferred to optimize the pH of the ferromagnetic metal powder depending upon a combination with a binder to be used. The pH range is usually from 6 to 12, and preferably from 7 to 11. Also, there is the case where the ferromagnetic powder contains inorganic ions such as soluble Na, Ca, Fe, Ni, Sr, NH4, SO4, Cl, NO2, and NO3. It is substantially preferable that the ferromagnetic powder does not contain such inorganic ions. When the total sum of the respective ions is approximately not more than 300 ppm, the characteristics are not affected. Also, it is preferable that the ferromagnetic powder to be used in the invention contains a small volume of voids. Its value is preferably not more than 20% by volume, and more preferably not more than 5% by volume. The crystallite size of the ferromagnetic metal powder is preferably from 8 to 20 nm, more preferably from 10 to 18 nm, and especially preferably 12 to 16 nm. This crystallite size is a mean value determined from half band widths of diffraction peaks using an X-ray diffraction analyzer (RINT2000 Series, manufactured by Rigaku Denki Co., Ltd.) under conditions of radiation source: CuKα1, X-ray tube voltage: 50 kV, and X-ray tube current: 300 mA according to the Scherrer method. The specific surface area (SBET) of the ferromagnetic metal powder according to the BET method is preferably 30 m2/g or more and less than 50 m2/g, and more preferably from 38 to 48 m2/g. Within this range, it is possible to cope with both good surface properties and low noises. It is preferred to optimize the pH of the ferromagnetic metal powder by a combination with a binder to be used. The pH range is from 4 to 12, and preferably from 7 to 10. If desired, the ferromagnetic metal powder may be subjected to a surface treatment with Al, Si, P, or oxides thereof. Its amount is from 0.1 to 10% based on the ferromagnetic metal powder. When the surface treatment is applied, the adsorption of a lubricant such as fatty acids becomes not more than 100 mg/m2, and hence, such is preferable. There is the case where the ferromagnetic metal powder contains inorganic ions such as soluble Na, Ca, Fe, Ni, and Sr. In this case, if the amount of the respective ions is approximately not more than 300 ppm, the characteristics are not particularly affected. Also, it is preferable that the ferromagnetic metal powder contains a small volume of voids. Its value is preferably not more than 20% by volume, and more preferably not more than 5% by volume. Also, so far as the foregoing characteristics regarding the grain size are met, the shape of the ferromagnetic metal powder may be in any of an acicular form, a granular form, a rice grain form, or a tabular form. Especially, it is preferred to use an acicular ferromagnetic metal powder. In the case of an acicular ferromagnetic metal powder, the acicular ratio is preferably from 4 to 12, and more preferably from 5 to 12. The coercive force (Hc) is preferably from 159.2 to 238.8 kA/m (from 2,000 to 3,000 Oe), and more preferably from 167.2 to 230.8 kA/m (from 2,100 to 2,900 Oe). Also, the saturation magnetic flux density is preferably from 150 to 300 mT (from 1,500 to 3,000 G), and more preferably from 160 to 290 mT (from 1,600 to 2,900 G). Also, the saturation magnetization (σs) is from 140 to 170 A-m2/kg (from 140 to 170 emu/g), and more preferably from 145 to 160 A-m2/kg (from 145 to 160 emu/g). It is preferable that SFD (switching field distribution) of the magnetic material itself is small, and the SFD is preferably not more than 0.8. When the SFD is not more than 0.8, the electromagnetic conversion characteristic is good, the output is high, and the reversal of magnetization is sharp so that the peak shift becomes small. Thus, such is suitable for high-density digital magnetic recording. In order to make the Hc distribution small, in the ferromagnetic metal powder, there are methods such as a method of improving the grain size distribution of goethite, a method of using monodispersed αFe2O3, and a method of preventing sintering among the grains. As the ferromagnetic metal powder, ones obtained by known production methods can be used, and the following methods can be enumerated. That is, examples include a method of reducing hydrous iron oxide having been subjected to a sintering preventing treatment or iron oxide with a reducing gas such as hydrogen to obtain an Fe or Fe—Co grain; a method of reducing a composite organic acid salt (mainly an oxalate) with a reducing gas such as hydrogen; a method of thermally decomposing a metallic carbonyl compound; a method of adding a reducing agent such as sodium borohydride, a hypophophite, and hydrazine to an aqueous solution of a ferromagnetic metal to reduce the ferromagnetic metal; and a method of evaporating a metal in a low-pressure inert gas to obtain a powder. The thus obtained ferromagnetic metal powder is subjected to a known gradual oxidation treatment. A method of reducing hydrous iron oxide or iron oxide with a reducing gas such as hydrogen and controlling the partial pressure of an oxygen-containing gas and an inert gas, the temperature and the time to form an oxide film on the surface is preferable because the demagnetization is small. <Ferromagnetic Hexagonal Ferrite Powder> Examples of the ferromagnetic hexagonal ferrite powder include barium ferrite, strontium ferrite, lead ferrite, calcium ferrite, and substituted bodies thereof with Co or the like. More specifically, there are enumerated magnetoplumbite type barium ferrite and strontium ferrite, magnetoplumbite type ferrite in which the grain surface is covered by spinel, and magnetoplumbite type barium ferrite and strontium ferrite containing partly a spinel phase. Besides, the ferromagnetic hexagonal ferrite powder may contain atoms such as Al, Si, S, Sc, Ti, V, Cr, Cu, Y, Mo, Rh, Pd, Ag, Sn, Sb, Te, Ba, Ta, W, Re, Au, Hg, Pb, Bi, La, Ce, Pr, Nd, P, Co, Mn, Zn, Ni, Sr, B, Ge, and Nb in addition to the prescribed atoms. In general, ones having added thereto elements such as Co—Zn, Co—Ti, Co—Ti—Zr, Co—Ti—Zn, Ni—Ti—Zn, Nb—Zn—Co, Sb—Zn—Co, and Nb—Zn can be used. Also, there are ones containing special impurities depending upon the raw material and production method. As described previously, the grain size of the ferromagnetic hexagonal ferrite powder has an average tabular diameter of from 5 to 40 nm, preferably from 10 to 38 nm, and more preferably from 15 to 36 nm. Also, the average tabular thickness is from 1 to 30 nm, preferably from 2 to 25 nm, and more preferably from 3 to 20 nm. An average tabular ratio {an average of [(tabular diameter)/(tabular thickness)]} is from 1 to 15, and preferably from 1 to 7. When the average tabular ratio falls within the range of from 1 to 15, not only sufficient orientation properties are obtained while keeping high packing properties in the magnetic layer, but also an increase of the noise can be suppressed by stacking among the grains. Also, the specific surface area according to the BET method within the foregoing grain size range is from 10 to 200 m2/g. This specific surface area generally coincides with a calculated value from the tabular diameter and tabular thickness of grain. In general, it is preferable that the distribution of the tabular diameter and tabular thickness of grain of the ferromagnetic hexagonal ferrite powder is narrow as far as possible. Digitalization of the tabular diameter and tabular thickness of grain can be compared by randomly measuring 500 grains from a grain TEM photograph. In many cases, the distribution of the tabular diameter and tabular thickness of grain is not a normal distribution. However, when the distribution of the tabular diameter and tabular thickness of grain is expressed in terms of a standard deviation against the average size upon calculation, σ/(average size) is from 0.1 to 2.0. In order to make the grain size distribution sharp, not only the grain forming reaction system is made uniform as far as possible, but also the formed grain is subjected to a distribution improving treatment. For example, there is known a method in which ultra-fine grains are selectively dissolved in an acid solution. Though the coercive force (Hc) of the hexagonal ferrite grain can be made to fall within the range of from 159.2 to 238.8 kA/m (from 2,000 to 3,000 Oe), the coercive force is preferably from 175.1 to 222.9 kA/m (from 2,200 to 2,800 Oe), and more preferably from 183.1 to 214.9 kA/m (from 2,300 to 2,700 Oe). However, in the case where the saturation magnetization (as) exceeds 1.4 T, the coercive force is preferably not more than 159.2 kA/m. The coercive force (Hc) can be controlled depending upon the grain size (tabular diameter and tabular thickness), the type and amount of an element to be contained, the substitution site of an element, the grain forming reaction condition, and so on. The saturation magnetization (σs) of the hexagonal ferrite grain is from 40 to 80 A·m2/kg (emu/g). Though it is preferable that the saturation magnetization (σs) is high, the saturation magnetization tends to become small as the grain becomes fine. For the sake of improving the saturation magnetization (σs), it is well known to make the magnetoplumbite ferrite composite with spinel ferrite and to select the type and addition amount of an element to be contained. Also, it is possible to use W-type hexagonal ferrite. In dispersing the magnetic material, it is also performed to treat the surface of the magnetic material grain with a substance adaptive to a dispersion medium and a polymer. As the surface treatment agent, inorganic compounds and organic compounds can be used. Representative examples thereof include oxides or hydroxides of Si, Al, P, etc., a variety of silane coupling agents, and a variety of titanium coupling agents. The addition amount of the surface treatment agent is from 0.1 to 10% by weight based on the weight of the magnetic material. The pH of the magnetic material is also important for the dispersion. The pH is usually from approximately 4 to 12 whiles its optimum value varies depending upon the dispersion medium and polymer. The pH is selected from the range of from approximately 6 to 11 in view of the chemical stability and preservability of the medium. The water content in the magnetic material affects the dispersion, too. The water content is usually selected from 0.01 to 2.0% while its optimum value varies depending upon the dispersion medium and polymer. Examples of the production method of the ferromagnetic hexagonal ferrite powder include (1) a glass crystallization method in which barium oxide, iron oxide and a metal oxide for substituting iron and boron oxide as a glass forming substance, and the like are mixed and molten so as to have a desired ferrite composition, the melt is quenched to form an amorphous body, and the amorphous body is again heated, washed and then pulverized to obtain a barium ferrite crystal powder; (2) a hydrothermal reaction method in which a barium ferrite composition metal salt solution is neutralized with an alkali, and after removing by-products, and the liquid phase is heated at 100° C. or higher, washed, dried and then pulverized to obtain a barium ferrite crystal powder; and (3) a coprecipitation method in which a barium ferrite composition metal salt solution is neutralized with an alkali, and after removing by-products, the residue is dried, treated at not higher than 1, 100° C. and then pulverized to obtain a barium ferrite crystal powder. The invention does not select the production method. If desired, the ferromagnetic hexagonal ferrite powder may be subjected to a surface treatment with Al, Si, P, or oxides thereof. Its amount is from 0.1 to 10% based on the ferromagnetic metal powder. When the surface treatment is applied, the adsorption of a lubricant such as fatty acids becomes not more than 100 mg/m2, and hence, such is preferable. There is the case where the ferromagnetic metal powder contains inorganic ions such as soluble Na, Ca, Fe, Ni, and Sr. While it is preferable that the ferromagnetic metal powder does not contain such an inorganic ion, if the content of the inorganic ion is not more than 200 ppm, the characteristics are not particularly affected. <Binder> The binder to be used in the magnetic layer of the invention includes conventionally known thermoplastic resins, thermosetting resins, reactive resins, and mixtures thereof. Examples of the thermoplastic resins include polymers or copolymers containing, as a constitutional unit, vinyl chloride, vinyl acetate, vinyl alcohol, maleic acid, acrylic acid, an acrylic ester, vinylidene chloride, acrylonitrile, methacrylic acid, a methacrylic ester, styrene, butadiene, ethylene, vinyl butyral, vinyl acetal, vinyl ether, etc., polyurethane resins, and a variety of rubber based resins. Also, examples of the thermosetting resins or reactive resins include phenol resins, epoxy resins, polyurethane hardening resins, urea resins, melamine resins, alkyd resins, acrylic reactive resins, formaldehyde resins, silicone resins, epoxy-polyamide resins, mixtures of a polyester resin and an isocyanate prepolymer, mixtures of a polyester polyol and a polyisocyanate, and mixtures of a polyurethane and a polyisocyanate. The thermoplastic resins, thermosetting resins and reactive resins are described in detail in Plastic Handbook, published by Asakura Shoten. Also, when an electron beam curable resin is used in the magnetic layer, not only the coating film strength is enhanced and the durability is improved, but also the surface is made smooth and the electromagnetic conversion characteristic is enhanced. Its examples and production method are described in detail in JP-A-62-256219. The foregoing resins can be used singly or in combinations thereof. Above all, it is preferred to use a polyurethane resin. Further, it is preferred to use a polyurethane resin obtained by reacting a cyclic structure (for example, hydrogenated bisphenol A and polypropylene oxide adducts of hydrogenated bisphenol A), a polyol having an alkylene oxide chain and having a molecular weight of from 500 to 5,000, a polyol having a cyclic structure and having a molecular weight of from 200 to 500 as a chain extender, and an organic diisocyanate; reacting with a polyurethane resin having a polar group introduced thereinto or an aliphatic dibasic acid (for example, succinic acid, adipic acid, and sebacic acid), a polyester polyol comprising a cyclic structure-free aliphatic diol having an alkyl branched side chain (for example, 2,2-dimethyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, and 2,2-diethyl-1,3-propanediol), an aliphatic diol having a branched alkyl side chain having 3 or more carbon atoms (for example, 2-ethyl-2-butyl-1,3-propanediol and 2,2-diethyl-1,3-propanediol) as a chain extender, and an organic diisocyanate compound; reacting with a polyurethane resin having a polar group introduced thereinto or a cyclic structure (for example, dimer diols), a polyol compound having a long chain alkyl chain, and an organic diisocyanate; and introducing a polar group. The mean molecular weight of the polar group-containing polyurethane based resin to be used in the invention is preferably from 5,000 to 100,000, and more preferably from 10,000 to 50,000. When the mean molecular weight is 5,000 or more, a lowering of the physical strength, such as the matter that the resulting magnetic coating film becomes brittle, does not take place so that the durability of the magnetic recording medium is not affected, and hence, such is preferable. Also, when the mean molecular weight is not more than 100,000, since the solubility in a solvent is not lowered, the dispersibility is good. Also, since the viscosity of the coating material does not increase in a prescribed concentration, the workability is good, and the handling is easy. Examples of the polar group to be contained in the foregoing polyurethane based resin include —COOM, —SO3M, —OSO3M, —P═O(OM)2, —O—P═O(OM)2 (wherein M represents a hydrogen atom or an alkali metal base), —OH, —NR2, —N+R3 (wherein R represents a hydrocarbon group), an epoxy group, —SH, and —CN. Ones into which at least one of these polar groups has been introduced by copolymerization or addition reaction can be used. Also, in the case where this polar group-containing polyurethane based resin has an OH group, it is preferred from the standpoints of curability and durability to have a branched OH group. The number of the branched OH group to be introduced is preferably from 2 to 40, and more preferably from 3 to 20 per molecule. The amount of the polar group is from 10−1 to 10−8 moles/g, and more preferably from 10−2 to 10−6 moles/g. Specific examples of the binder include VAGH, VYHH, VMCH, VAGF, VAGD, VROH, VYES, VYNC, VMCC, XYHL, XYSG, PKHH, PKHJ, PKHC and PKFE (all of which are manufactured by Union Carbide Corporation); MPR-TA, MPR-TA5, MPR-TAL, MPR-TSN, MPR-TMF, MPR-TS, MPR-TM and MPR-TAO (all of which are manufactured by Nissin Chemical Industry Co., Ltd.); 1000W, DX80, DX81, DX82, DX83 and 100FD (all of which are manufactured by Denki Kagaku Kogyo Kabushiki Kaisha); MR-104, MR-105, MR110, MR100, MR555 and 400X-110A (all of which are manufactured by Zeon Corporation); Nipporan N2301, Nipporan N2302 and Nipporan N2304 (all of which are manufactured by Nippon Polyurethane Industry Co., Ltd.); Pandex T-5105, Pandex T-R3080, Pandex T-5201, Burnock D-400, Burnock D-210-80, Crisvon 6109 and Crisvon 7209 (all of which are manufactured by Dainippon Ink and Chemicals, Incorporated); Vylon UR8200, Vylon UR8300, Vylon UR-8700, Vylon RV530 and Vylon RV280 (all of which are manufactured by Toyobo Co., Ltd.); Daiferamine 4020, Daiferamine 5020, Daiferamine 5100, Daiferamine 5300, Daiferamine 9020, Daiferamine 9022 and Daiferamine 7020 (all of which are manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.); MX5004 (manufactured by Mitsubishi Chemical Corporation); Sanprene SP-150 (manufactured by Sanyo Chemical Industries, Ltd.); and Saran F310 and Saran F210 (all of which are manufactured by Asahi Kasei Corporation). The addition amount of the binder which is used in the magnetic layer of the invention is in the range of from 5 to 50% by weight, and preferably in the range of from 10 to 30% by weight based on the weight of the ferromagnetic metal powder. In the case where a polyurethane resin is used, it is preferred to use a combination containing from 2 to 20% by weight of a polyurethane resin and from 2 to 20% by weight of a polyisocyanate. For example, in the case where a head is corroded due to dechlorination of a slight amount, it is possible to use only a polyurethane or only a polyurethane and a polyisocyanate. In the case where a vinyl chloride based resin is used as other resin, its amount is preferably in the range of from 5 to 30% by weight. In the invention, in the case where a polyurethane is used, it is preferable that the glass transition temperature is from −50 to 150° C., and preferably from 0 to 100°C.; the breaking elongation is from 100 to 2,000%; the breaking stress is from 0.49 to 98 MPa (from 0.05 to 10 kg/mm2); and the yield point is from 0.49 to 98 MPa (0.05 to 10 kg/mm2). The magnetic recording medium to be used in the invention can be constructed of two or more layers in one side of the polymer support. Accordingly, as a matter of course, it is possible to change the amount of the binder, the amount of the vinyl chloride based resin occupied in the binder, the polyurethane resin, the polyisocyanate, or other resin, the molecular weight and the amount of the polar group of each of the resins for forming the magnetic layer, or the physical characteristics of the resin as described previously depending upon the non-magnetic layer and the respective magnetic layers, as the need arises. However, these parameters should be optimized in each layer, and known technologies regarding multilayered magnetic layers can be applied. For example, in the case where the amount of the binder is changed in each layer, in order to reduce scratches on the surface of the magnetic layer, it is effective to increase the amount of the binder of the magnetic layer; and in order to make head touch against a head good, it is possible to impart flexibility by increasing the amount of the binder of the non-magnetic layer. Examples of the polyisocyanate which can be used in the invention include isocyanates (for example, tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, naphthylene-1,5-diisocyanate, o-toluidine diisocyanate, isophorone diisocyanate, and triphenylenemethane triisocyanate); products between such an isocyanate and a polyalcohol; and polyisocyanates formed by condensation of an isocyanate. Examples of trade names of commercially available isocyanates include Coronate L, Coronate HL, Coronate 2030, Coronate 2031, Millionate MR and Millionate MTL (all of which are manufactured by Nippon Polyurethane Industry Co., Ltd.); Takenate D-102, Takenate D-100N, Takenate D-200 and Takenate D-202 (all of which are manufactured by Takeda Pharmaceutical Company Limited); and Desmodule L, Desmodule IL, Desmodule N and Desmodule HL (all of which are manufactured by Sumitomo Bayer Urethane Co., Ltd.). In each layer, these materials can be used singly or in combinations of two or more thereof utilizing a difference in the curing reactivity. If desired, an additive can be added in the magnetic layer in the invention. As the additive, an abrasive, a wetting agent, a dispersant, a dispersing agent, an anti-mildew agent, an antistatic agent, an antioxidant, a solvent, carbon black, etc. can be enumerated. Examples of the additive include molybdenum disulfide; tungsten disulfide; graphite; boron nitride; fluorinated graphite; silicone oil; polar group-containing silicones; fatty acid-modified silicones; fluorine-containing silicones; fluorine-containing alcohols; fluorine-containing esters; polyolefins; polyglycols; polyphenyl ethers; aromatic ring-containing organic phosphonic acids (for example, phenylsulfonic acid, benzylphosphonic acid, phenethylphosphonic acid, α-methylbenzylphosphonic acid, 1-methyl-1-phenethylphosphonic acid, diphenylmethylphosphonic acid, biphenylphosphonic acid, benzylphenylphosphonic acid, α-cumylphosphonic acid, toluylphosphonic acid, xylylphosphonic acid, ethylphenylphosphonic acid, cumenylphosphonic acid, propylphenylphosphonic acid, butylphenylphosphonic acid, heptylphenylphosphonic acid, octylphenylphosphonic acid, and nonylphenylphosphonic acid) and alkali metal salts thereof; alkylphosphonic acids (for example, octylphosphonic acid, 2-ethylhexylphosphonic acid, isooctylphosphonic acid, isononylphosphonic acid, isodecylphosphonic acid, isoundecylphosphonic acid, isodecylphosphonic acid, isohexadecylphosphonic acid, isooctadecylphosphonic acid, and isoeicosylphosphonic acid) and alkali metal salts thereof; aromatic phosphoric esters (for example, phenyl phosphate, benzyl phosphate, phenethyl phosphate, α-methylbenzyl phosphate, 1-methyl-1-phenethyl phosphate, diphenylmethyl phosphate, biphenyl phosphate, benzylphenyl phosphate, α-cumyl phosphate; toluyl phosphate, xylyl phosphate, ethylphenyl phosphate, cumenyl phosphate, propylphenyl phosphate, butylphenyl phosphate, heptylphenyl phosphate, octylphenyl phosphate, and nonylphenyl phosphate) and alkali metal salts thereof; phosphoric acid alkyl esters (for example, octyl phosphate, 2-ethylhexyl phosphate, isooctyl phosphate, isononyl phosphate, isodecyl phosphate, isoundecyl phosphate, isodecyl phosphate, isohexadecyl phosphate, isooctadecyl phosphate, and isoeicosyl phosphate) and alkali metal salts thereof; alkylsulfonic esters and alkali metal salts thereof; monobasic fatty acids having from 10 to 24 carbon atoms, which may contain an unsaturated bond or may be branched (for example, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, butyl stearate, oleic acid, linolic acid, linoleic acid, elaidic acid, and erucic acid) and metal salts thereof; mono-fatty acid esters, di-fatty acid esters or polyhydric fatty acid esters comprising a monobasic fatty acid having from 10 to 24 carbon atoms, which may contain an unsaturated bond or may be branched, any one of a monohydric to hexahydric alcohol having from 2 to 22 carbon atom, which may contain an unsaturated bond or may be branched, an alkyl alcohol having from 12 to 22 carbon atoms, which may contain an unsaturated bond or may be branched, and a monoalkyl ether of an alkylene oxide adduct (for example, butyl stearate, octyl stearate, amyl stearate, isooctyl stearate, octyl myristate, butyl laurate, butoxyethyl stearate, anhydrosorbitan monostearate, and anhydrosorbitan tristearate); fatty acid amides having from 2 to 22 carbon atoms; and fatty acid amines having from 8 to 22 carbon atoms. Also, ones having an alkyl group, an aryl group, or an aralkyl group, in which a nitro group and a group other than hydrocarbon groups such as halogen-containing hydrocarbons, for example F, Cl, Br, CF3, CCl3, and CBr3, are substituted besides the foregoing hydrocarbon groups may be employed. Also, nonionic surfactants (for example, alkylene oxide based surfactants, glycerin based surfactants, glycidol based surfactants, and alkylphenol ethylene oxide adducts); cationic surfactants (for example, cyclic amines, ester amides, quaternary ammonium salts, hydantoin derivatives, heterocyclic compounds, phosphoniums, and sulfoniums); anionic surfactants containing an acid group such as a carboxyl group, a sulfonic group, and a sulfuric ester group; and ampholytic surfactants (for example, amino acids, aminosufonic acids, amino alcohol sulfuric or phosphoric esters, and alkyl betaine types) can be used. These surfactants are described in detail in Surfactant Handbook (published by Sangyo Tosho Publishing Co., Ltd.). The foregoing wetting agent and antistatic agent, and the like are not necessarily pure and may contain impurities such as isomers, unreacted compounds, by-products, decomposition products, and oxides in addition to the major components. The content of these impurities is preferably not more than 30% by weight, and more preferably not more than 10% by weight. Specific examples of these additives include NAA-102, castor oil hydrogenated fatty acids, NAA-42, Cation SA, Nymeen L-201, Nonion E-208, Anon BF and Anon LG (all of which are manufactured by NOF Corporation); FAL-205 and FAL-123 (all of which are manufactured by Takemoto Oil and Fat Co., Ltd.); Enujelub OL (manufactured by New Japan Chemical Co., Ltd.); TA-3 (manufactured by Shin-Etsu Chemical Co., Ltd.); Amide P (manufactured by Lion Armour Co., Ltd.); Duomeen TDO (manufactured by Lion Corporation); BA-41G (manufactured by Nisshin Oil Co., Ltd.); and Profan 2012E, Newpol PE61 and Ionet MS-400 (all of which are manufactured by Sanyo Chemical Industries, Ltd.). Also, if desired, carbon black can be added to the magnetic layer in the invention. Examples of the carbon black which can be used in the magnetic layer include furnace black for rubber, thermal black for rubber, carbon black for color, and acetylene black. It is preferable that the carbon black has a specific surface area of from 5 to 500 m2/g, a DBP oil absorption of from 10 to 400 mL/100 g, a grain size of from 5 to 300 mμ, a pH of from 2 to 10, a water content of from 0.1 to 10%, and a tap density of from 0.1 to 1 g/mL. Specific examples of the carbon black which is used in the invention include BLACKPEARLS 2000, 1300, 1000, 900, 905, 800 and 700 and VULCAN XC-72 (all of which are manufactured by Cabot Corporation); #80, #60, #55, #50 and #35 (all of which are manufactured by Asahi Carbon Co., Ltd.); #2400B, #2300, #900, #1000, #30, #40 and #10B (all of which are manufactured by Mitsubishi Chemical Corporation); CONDUCTEX SC, RAVEN 150, 50, 40 and 15 and RAVEN-MY-P (all of which are Columbia Carbon Co.); and Ketchen Black EC (manufactured by Nippon EC K.K.). The carbon black may be subjected to a surface treatment with a dispersant, grafting with a resin, or partial surface graphitization. Also, these carbon blacks can be used singly or in combinations. In the case where the carbon black is used, the carbon black is preferably used in an amount of from 0.1 to 30% by weight based on the weight of the magnetic material. The carbon black has functions to prevent the charging of the magnetic layer, to reduce the coefficient of friction, to impart the light shielding properties, and to enhance the film strength. Such functions vary depending upon the type of the carbon black to be used. Accordingly, as a matter of course, it is possible to properly choose and use the carbon black to be used in the invention by changing the type, the amount and the combination in the magnetic layer and the non-magnetic layer depending upon the purpose based on the various characteristics as defined previously such as the grain size, the oil absorption, the conductivity, and the pH. Rather, they should be optimized for the respective layers. With respect to the carbon black which is used in the magnetic layer of the invention, for example, Carbon Black Handbook, complied by the Carbon Black Association of Japan can be made hereof by reference. As the organic solvent to be used in the invention, known organic solvents can be used. The organic solvent to be used in the invention can be used in an arbitrary ratio, and examples thereof include ketones (for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, isophorone, and tetrahydrofuran); alcohols (for example, methanol, ethanol, propanol, butanol, isobutyl alcohol, isopropyl alcohol, and methylcyclohexanol); esters (for example, methyl acetate, butyl acetate, isobutyl acetate, isopropyl acetate, ethyl lactate, and glycol acetate); glycol ethers (for example, glycol dimethyl ether, glycol monoethyl ether, and dioxane); aromatic hydrocarbons (for example, benzene, toluene, xylene, cresol, and chlorobenzene); chlorinated hydrocarbons (for example, methylene chloride, ethylene chloride, carbon tetrachloride, chloroform, ethylene chlorohydrin, and dichlorobenzene); N,N-dimethylformamide; and hexane. These organic solvents are not necessarily completely pure and may contain impurities such as isomers, unreacted compounds, by-products, decomposition products, oxides, and moisture in addition to the major components. The content of these impurities is preferably not more than 30% by weight, and more preferably not more than 10% by weight. With respect to the organic solvent to be used in the invention, it is preferable that the type thereof is the same between the magnetic layer and the non-magnetic layer. The addition amount of the organic solvent may be varied. It is important to enhance the coating stability using a solvent having a high surface tension (for example, cyclohexanone and dioxane) in the non-magnetic layer. Specifically, the arithmetical average values of the solvent composition of the upper layer should not be lower than the arithmetical average values of the solvent composition of the non-magnetic layer. For the sake of improving the dispersibility, it is preferable that the polarity is strong to some extent. Among the solvent compositions, it is preferable that a solvent having a dielectric constant of 15 or more is contained in an amount of 50% or more. Also, the solubility parameter is preferably from 8 to 11. With respect to the dispersant, the wetting agent and the surfactant which are used in the invention, the type and amount thereof can be properly chosen and used in the magnetic layer and the non-magnetic layer as described later as the need arises. As a matter of course, it should not be construed that the invention is limited to the examples described herein. For example, the dispersant has such properties that it causes adsorption or binding at the polar group, and causes adsorption or binding at the polar group mainly on the surface of the ferromagnetic metal powder in the magnetic layer and mainly on the surface of non-magnetic powder in the non-magnetic layer, respectively. For example, it is estimated that an organophosphorus compound having been once adsorbed is hardly desorbed from the surface of the metal or metallic compound, etc. Accordingly, since the surface of the ferromagnetic metal power or the surface of the non-magnetic powder is in the state where it is covered by an alkyl group, an aromatic group, etc., the compatibility of the ferromagnetic metal powder or non-magnetic powder with the binder resin component is enhanced, and the dispersion stability of the ferromagnetic metal powder or non-magnetic powder is further improved. Also, since the wetting agent is present in the free state, there may be considered a method in which the bleed-through onto the surface is controlled by using a fatty acid having a different melting point in each of the non-magnetic layer and the magnetic layer; a method in which the bleed-through onto the surface is controlled by using an ester having a different boiling point or polarity; a method in which the coating stability is enhanced by adjusting the amount of the surfactant; and a method in which the lubricating effect is enhanced by making the addition amount of the lubricant higher in the non-magnetic layer. Also, all or a part of the additives which are used in the invention may be added in any of the steps at the time of producing a coating liquid for magnetic layer or non-magnetic layer. Examples thereof include the case of mixing with the ferromagnetic powder before the kneading step, the case of addition in the kneading step of the ferromagnetic powder, the binder and the solvent, the case of addition in the dispersion step, the case of addition after the dispersion, and the case of addition immediately before coating. [Non-Magnetic Layer] Next, the detailed contents of the non-magnetic layer will be described below. The magnetic recording medium of the invention can have a non-magnetic layer containing a binder and a non-magnetic powder on the polymer support. The non-magnetic powder which can be used in the non-magnetic layer may be an inorganic substance or an organic substance. Also, carbon black or the like can be used. Examples of the inorganic substance include metals, metal oxides, metal carbonates, metal sulfates, metal nitrides, metal carbides, and metal sulfides. Specifically, titanium oxides such as titanium dioxide, cerium oxide, tin oxide, tungsten oxide, ZnO, ZrO2, SiO2, Cr2O3, α-alumina having a rate of conversion to an α-form of from 90 to 100%, β-alumina, γ-alumina, α-iron oxide, goethite, corundum, silicon nitride, titanium carbide, magnesium oxide, boron nitride, molybdenum disulfide, copper oxide, MgCO3, CaCO3, BaCO3, SrCO3, BaSO4, silicon carbide, titanium carbide, and the like are used singly or in combinations of two or more kinds thereof. Of these, α-iron oxide and titanium oxide are preferable. The shape of the non-magnetic powder may be any of the acicular, spherical, polyhedral or tabular form. The crystallite size of the non-magnetic powder is preferably from 4 nm to 1 μm, and more preferably from 40 to 100 nm. When the crystallite size falls within the range of from 4 nm to 1 μm, not only the dispersion does not become difficult, but also a proper surface roughness is obtained, and therefore, such is preferable. The mean grain size of the non-magnetic powder is preferably from 5 nm to 2 μm. If desired, it is possible to bring the same effect by combining non-magnetic powders having a different mean grain size from each other or broadening the grain size distribution even in a single non-magnetic powder. The mean grain size of the non-magnetic powder is especially preferably from 10 to 200 nm. When the mean grain size falls within the range of from 5 nm to 2 μm, not only the dispersion is good, but also a suitable surface roughness is obtained, and therefore, such is preferable. The specific surface area of the non-magnetic powder is from 1 to 100 m2/g, preferably from 5 to 70 m2/g, and more preferably from 10 to 65 m2/g. When the specific surface area falls within the range of from 1 to 100 m2/g, not only a suitable surface roughness is obtained, but also the dispersion can be achieved in a desired amount of the binder, and therefore, such is preferable. The oil absorption using dibutyl phthalate (DBP) is from 5 to 100 mL/100 g, preferably from 10 to 80 mL/100 g, and more preferably from 20 to 60 mL/100 g. The specific gravity is from 1 to 12, and preferably from 3 to 6. The tap density is from 0.05 to 2 g/mL, and preferably from 0.2 to 1.5 g/mL. When the tap density falls within the range of from 0.05 to 2 g/mL, not only the grains are scattered a little so that the operation is easy. Also, the no-magnetic powder tends to hardly fix to the device. The pH of the non-magnetic powder is preferably from 2 to 11, and especially preferably from 6 to 9. When the pH falls within the range of from 2 to 11, the non-magnetic powder is free from an increase of the coefficient of friction caused at high temperature and high humidity conditions or due to the liberation of a fatty acid. The water content of the non-magnetic powder is from 0.1 to 5% by weight, preferably from 0.2 to 3% by weight, and more preferably from 0.3 to 1.5% by weight. When the water content falls within the range of from 0.1 to 5% by weight, not only the dispersion is good, but also the viscosity of the coating material after the dispersion is stable, and therefore, such is preferable. The ignition loss is preferably not more than 20% by weight, and it is preferable that the ignition loss is low. Also, in the case where the non-magnetic powder is an inorganic powder, ones having a Moh's hardness of from 4 to 10 are preferable. When the Moh's hardness falls within the range of from 4 to 10, it is possible to ensure the durability. The stearic acid adsorption of the non-magnetic powder is preferably from 1 to 20 μmoles/m2, and more preferably from 2 to 15 μmoles/m2. The heat of wetting of the non-magnetic powder to water at 25° C. is preferably in the range of from 200 to 600 erg/cm2 (from 200 to 600 mJ/m2). Also, it is possible to use a solvent whose heat of wetting falls within this range. The amount of the water molecule on the surface at from 100 to 400° C. is properly from 1 to 10 per 100 angstroms. The pH of the isoelectric point in water is preferably from 3 to 9. It is preferable that Al2O3, SiO2, TiO2, ZrO2, SnO2, Sb2O3, or ZnO is present on the surface of the non-magnetic powder through a surface treatment. In particular, in view of the dispersibility, Al2O3, SiO2, TiO2 and ZrO2 are preferable, and Al2O3, SiO2 and ZrO2 are more preferable. These compounds may be used in combinations. Also, these compounds can be used singly. Also, a surface-treated layer resulting from co-precipitation may be used depending upon the purpose. Also, a method in which the surface layer is first treated with alumina and then treated with silica, or its reversal method may be employed. The surface-treated layer may be a porous layer depending upon the purpose, but it is generally preferable that the surface-treated layer is uniform and dense. Specific examples of the non-magnetic powder which is used in the non-magnetic layer of the invention include Nanotite (manufactured by Showa Denko K.K.); HIT-100 and ZA-G1 (all of which are manufactured by Sumitomo Chemical Co., Ltd.); DPN-250, DPN-250BX, DPN-245, DPN-270BX, DPB-550BX and DPN-550RX (all of which are manufactured by Toda Kogyo Corp.); titanium oxide, for example, TTO-51B, TTO-55A, TTO-55B, TTO-55C, TTO-55S, TTO-55D, SN-100 and MJ-7 and α-iron oxide, for example, E270, E271 and E300 (all of which are manufactured by Ishihara Sangyo Kaisha, Ltd.); STT-4D, STT-30D, STT-30 and STT-65C (all of which are manufactured by Titan Kogyo Kabushiki Kaisha); MT-100S, MT-100T, MT-150W, MT-500B, T-600B, T-100F and T-500HD (all of which are manufactured by Tayca Corporation); FINEX-25, BF-1, BF-10, BF-20 and ST-M (all of which are manufactured by Sakai Chemical Industry Co., Ltd.); DEFIC-Y and DEFIC-R (all of which are manufactured by Dowa Mining Co., Ltd.); AS2BM and TiO2P25 (all of which are manufactured by Nippon Aerosil Co., Ltd.); 100A and 500A (all of which are manufactured by Ube Industries, Ltd.); and Y-LOP and calcination products thereof (all of which are manufactured by Titan Kogyo Kabushiki Kaisha). Particularly preferred non-magnetic powders are titanium dioxide and α-iron oxide. By mixing carbon black together with the non-magnetic powder in the non-magnetic layer, it is possible to lower the surface electrical resistance, to reduce the light transmittance and to obtain a desired micro Vickers hardness. The micro Vickers hardness of the non-magnetic layer is usually from 25 to 60 kg/mm2 (from 245 to 588 MPa), and preferably from 30 to 50 kg/mm2 (from 294 to 490 MPa) for the purpose of adjusting the touch with a head. The micro Vickers hardness can be measured using a hardness tester for thin film (HMA-400, manufactured by NEC Corporation) and using a diamond-made triangular pyramid stylus having a sharpness of 80° and a tip radius of 0.1 μm at the tip of an indenter. The light transmittance is generally regulated such that the absorption of infrared light having a wavelength of approximately 900 nm is not more than 3%, for example, in a magnetic tape for VHS, it is not more than 0.8%. For achieving this, furnace black for rubber, thermal black for rubber, carbon black for color, acetylene black, etc. can be used. The carbon black to be used in the non-magnetic layer of the invention has a specific surface area of from 100 to 500 m2/g, and preferably from 150 to 400 m2/g and a DBP oil absorption of from 20 to 400 mL/100 g, and preferably from 30 to 200 mL/100 g. The carbon black has a grain size of from to 80 nm, preferably from 10 to 50 nm, and more preferably from 10 to 40 nm. The carbon black preferably has a pH of from 2 to 10, a water content of from 0.1 to 10%, and a tap density of from 0.1 to 1 g/mL. Specific examples of the carbon black which can be used in the non-magnetic layer of the invention include BLACKPEARLS 2000, 1300, 1000, 900, 800, 880 and 700 and VULCAN XC-72 (all of which are manufactured by Cabot Corporation); #3050B, #3150B, #3250B, #3750B, #3950B, #950, #650B, #970B, #850B and MA-600 (all of which are manufactured by Mitsubishi Chemical Corporation); CONDUCTEX SC and RAVEN 8800, 8000, 7000, 5750, 5250, 3500, 2100, 2000, 1800, 1500, 1255 and 1250 (all of which are Columbia Carbon Co.); and Ketchen Black EC (manufactured by AKZONOBLE). Also, the carbon black may be subjected to a surface treatment with a dispersant, grafting with a resin, or partial surface graphitization. Also, the carbon black may be dispersed with a binder prior to the addition to the coating material. The carbon black can be used in an amount in the range not exceeding 50% by weight based on the foregoing inorganic powder and in the range not exceeding 40% based on the total weight of the non-magnetic layer. These carbon blacks can be used singly or in combinations. With respect to the carbon black which can be used in the non-magnetic layer of the invention, for example, Carbon Black Handbook, complied by the Carbon Black Association of Japan can be made hereof by reference. Also, an organic powder can be added to the non-magnetic layer depending upon the purpose. Examples of the organic powder include an acrylic-styrene based resin powder, a benzoguanamine resin powder, a melamine based resin powder, and a phthalocyanine based pigment. It is also possible to use a polyolefin based resin powder, a polyester based resin powder, a polyamide based resin powder, a polyimide based resin powder, or a polyethylene fluoride resin. Examples of the production method thereof include those described in JP-A-62-18564 and JP-A-60-255827. With respect to a binder resin, a lubricant, a dispersant, additives, a solvent, a dispersion method, and others of the non-magnetic layer, those in the magnetic layer can be applied. In particular, with respect to the amount and type of the binder resin and the addition amount and type of the dispersant, known technologies regarding the magnetic layer can be applied. [Back Layer and Undercoat Layer] In general, magnetic tapes for recording computer data are strongly required to have repeated running properties as compared with video tapes and audio tapes. For the purpose of keeping such high running durability, it is also possible to provide a back layer on the surface of the polymer support opposite to the surface thereof on which the non-magnetic layer and the magnetic layer are provided. The coating material for back layer is prepared by dispersing granular components such as an abrasive and an antistatic agent and a binder in an organic solvent. Examples of the granular components include a variety of inorganic pigments and carbon black. Also, examples of the binder include nitrocellulose, a phenoxy resin, a vinyl chloride based resin, and a polyurethane. They can be used singly or in admixture thereof. In the polymer support of the invention, an adhesive layer may be provided on the surface on which the coating material for magnetic layer or the coating material for back layer is coated. Also, the magnetic recording medium of the invention may be provided with an undercoat layer. By providing an undercoat layer, it is possible to enhance an adhesive force between the polymer support and the magnetic layer or the non-magnetic layer. A polyester resin which is soluble in a solvent is used as the undercoat layer. The thickness of the undercoat layer is not more than 0.5 sun. [Layer Construction] With respect to the thickness construction of the magnetic recording medium to be used in the invention, the thickness of the polymer support is preferably from 3 to 8 μm. As the polymer support of the magnetic tape, ones having a thickness in the range of from 3 to 7 μm (preferably from 3.5 to 7.5 μm) are used. In the case where the undercoat layer is provided between the polymer support and the non-magnetic layer or the magnetic layer, the thickness of the undercoat layer is from 0.01 to 0.8 μm, and preferably from 0.02 to 0.6 μm. Also, the thickness of the back layer to be provided on the surface of the polymer support opposite to the surface on which the non-magnetic layer and the magnetic layer are provided is from 0.1 to 1.0 μm, and preferably from 0.2 to 0.8 μm. The thickness of the magnetic layer is optimized depending upon the saturation magnetization of the magnetic head to be used, the head cap length, and the recording signal zone and is in general from 10 to 100 nm, preferably from 20 to 80 nm, and more preferably from 30 to 80 nm. Also, the coefficient of fluctuation in the thickness of the magnetic layer is preferably within ±50%, and more preferably within ±40%. The magnetic layer may comprise at least one layer and may be separated into two or more layers having a different magnetic characteristic from each other, and a known construction regarding the multilayered magnetic layer can be applied. The thickness of the non-magnetic layer of the invention is from 0.5 to 2.0 μm, preferably from 0.8 to 1.5 μm, and more preferably from 0.8 to 1.2 μm. Incidentally, the non-magnetic layer of the magnetic recording medium of the invention can reveal its effect so far as it is substantially non-magnetic. For example, even when a small amount of a magnetic material is intentionally contained as an impurity, the effect of the invention is revealed, and this construction can be considered substantially identical with that of the magnetic recording medium of the invention. Incidentally, what the construction is substantially identical means that the non-magnetic layer has a residual magnetic flux density of not more than 10 mT or a coercive force of not more than 7.96 kA/m (100 Oe), and preferably has neither residual magnetic flux density nor coercive force. [Production Method] The method of producing a coating liquid for magnetic layer of the magnetic recording medium to be used in the invention comprises at least a kneading step, a dispersion step, and a mixing step which is optionally provided prior to or after the foregoing steps. Each of these steps may be divided to two or more stages. All of the raw materials including the ferromagnetic metal powder, the non-magnetic powder, the binder, the carbon black, the abrasive, the antistatic agent, the lubricant, and the solvent may be added at the initial stage of or during any of the steps. Also, the addition of each raw material may be divided across two or more steps. For example, the polyurethane may be divided and added in the kneading step, the dispersion step, and the mixing step for adjusting the viscosity after the dispersion. In order to achieve the object of the invention, a conventionally known production technology can be employed as a part of the step. In the kneading step, it is preferred to use a powerful kneading machine such as an open kneader, a continuous kneader, a pressure kneader, and an extruder. In the case where a kneader is used, all or a part of the binder (preferably 30% or more of the entire binder) is kneaded with the magnetic powder or the non-magnetic powder in an amount in the range of from 15 to 500 parts by weight based on 100 parts by weight of the magnetic material. The details of these kneading treatments are described in JP-A-1-106338 and JP-A-1-79274. Also, for the purpose of dispersing the liquid for magnetic layer and the liquid for non-magnetic layer, glass beads can be used. As the glass beads, dispersion media having a high specific gravity, such as zirconia beads, titania beads, and steel beads, are suitable. These dispersion media are used upon optimization of the grain size and packing density. A known dispersing machine can be used. In the production method of the magnetic recording medium of the invention, for example, the magnetic layer is formed such that the magnetic coating liquid is coated in a prescribed thickness on the surface of the polymer support under running. Here, a plurality of coating liquids for magnetic layer may be sequentially or simultaneously laminated and coated, and the coating liquid for non-magnetic layer and the coating liquid for magnetic layer may be sequentially or simultaneously laminated and coated. As the coating machine for coating the foregoing coating liquid for magnetic layer or coating liquid for non-magnetic layer, an air doctor coater, a blade coater, a rod coater, an extrusion coater, an air knife coater, a squeeze coater, a dip coater, a reverse roll coater, a transfer roll coater, a gravure coater, a kiss coater, a cast coater, a spray coater, a spin coater, and the like can be utilized. With respect to these matters, Latest Coating Technologies, published by Sogo Gijutsu Center K.K. (Mary 31, 1983) can be made hereof by reference. In the case of a magnetic tape, with respect to the coating layer of the coating liquid for magnetic layer, the ferromagnetic metal powder contained in the coating layer of the coating liquid for magnetic layer is subjected to a magnetic orientation treatment with a cobalt magnet or a olenoid in the machine direction. In the case of a disc, although sufficient isotropic orientation properties may possibly be obtained without subjecting to orientation using an orientation device, it is preferred to alternately align cobalt magnets in the oblique direction or to use a known random orientation device involving, for example, applying an alternating magnetic field using a solenoid. In the case of the ferromagnetic metal powder, with respect to the isotropic orientation as referred to herein, in general, in-plane two-dimensional random is preferable, but three-dimensional random can be employed by imparting a vertical component. In the case of the hexagonal ferrite, in general, the orientation is liable to become three-dimensional random within the plane and in the vertical direction, but it is possible to employ in-plane two-dimensional random. Also, it is possible to impart an isotropic magnetic characteristic in the peripheral direction by vertical orientation according to a known method involving, for example, applying heteropolar facing magnets. In particular, in the case of carrying out high-density recording, the vertical orientation is preferable. Also, it is possible to carry out peripheral orientation using a spin coater. It is preferable that the drying position of the coating film can be controlled by controlling the temperature and volume of drying air and the coating rate. The coating rate is preferably from 20 m/min to 1,000 m/min; and the temperature of the drying air is preferably 60° C. or higher. Also, it is possible to carry out proper preliminary drying before entering the magnet zone. After drying, the coating layer is usually subjected to a surface smoothening treatment. For the surface smoothening treatment, for example, supercalender rolls and the like are utilized. By carrying out the surface smoothening treatment, voids generated by the removal of the solvent at the time of drying disappear, whereby the packing density of the ferromagnetic metal powder in the magnetic layer is enhanced. Accordingly, a magnetic recording medium having a high electromagnetic conversion characteristic can be obtained. As rolls for the calender treatment, heat resistant plastic rolls such as epoxy, polyimide, polyamide, or polyamideimide rolls are used. Also, the treatment can be carried out using metal rolls. It is preferable that the magnetic recording medium of the invention has a surface having extremely excellent smoothness such that the center plane average height of the surface is in the range of from 0.1 to 4 nm, and preferably from 1 to 3 nm in terms of the cut-off value. For example, its method is carried out by subjecting the magnetic layer which is formed by selecting the specific ferromagnetic metal powder and binder as described previously to the foregoing calender treatment. The calender treatment is carried out by actuating the rolls under conditions at a calender roll temperature in the range of from 60 to 100° C., preferably in the range of from 70 to 100° C., and especially preferably in the range of from 80 to 100° C. and under a pressure in the range of from 100 to 500 kg/cm (from 98 to 490 kN/m), preferably in the range of from 200 to 450 kg/cm (from 196 to 441 kN/m), and especially preferably in the range of from 300 to 400 kg/cm (from 294 to 392 kN/m). Examples of means for reducing the rate of heat shrinkage include a method of carrying out the heat treatment in the web form while handling at a low tension and a method of carrying out the heat treatment in the bulk state or the laminated state of a tape such as the built-in state in a cassette (thermo-treatment method), and the both can be utilized. The thermo-treatment method is preferable from the viewpoint of providing a magnetic recording medium having a high output and a low noise. The obtained magnetic recording medium can be cut into a desired size using a cutting machine, etc. and then provided for use. The cutting machine is not particularly limited. However, ones provided with a plurality of pairs of rotating upper blade (male blade) and lower blade (female blade) are preferable, and the slitting rate, the contact depth, the peripheral speed ratio of the upper blade (male blade) to the lower blade (female blade) (peripheral speed of upper blade/peripheral speed of lower blade), the continuous use time of the slit blades, and so on are adequately chosen. [Physical Characteristics] The saturation magnetic flux density of the magnetic layer of the magnetic recording medium to be used in the invention is preferably from 100 to 300 mT. Also, the coercive force (Hc) of the magnetic layer is from 143.3 to 318.4 kA/m (from 1,800 to 4,000 Oe), and more preferably from 159.2 to 278.6 kA/m (from 2,000 to 3,500 Oe). The distribution of the coercive force is preferably narrow. The SFD and SFDr are each preferably not more than 0.6, and more preferably not more than 0.2. The coefficient of friction of the magnetic recording medium to be used in the invention against the head is not more than 0.5, and preferably not more than 0.3 within the range wherein the temperature is from −10 to 40° C. and the humidity is from 0 to 95%. Also, the surface intrinsic resistance is preferably from 104 to 1012 Ω/sq on the magnetic surface; and the charge potential is preferably within the range of from −500 V to +500 V. The magnetic layer preferably has an elastic modulus at 0.5% elongation of from 0.98 to 19.6 GPa (from 100 to 2,000 kg/mm2) in the respective directions within the plane and a breaking strength of from 98 to 686 MPa (from 10 to 70 kg/mm2). The magnetic recording medium preferably has an elastic modulus of from 0.98 to 14.7 GPa (from 100 to 1,500 kg/mm2) in the respective directions within the plane, a residual elongation of not more than 0.5%, and a rate of heat shrinkage of not more than 1%, more preferably not more than 0.5%, and most preferably not more than 0.1% at any temperature of not more than 100° C. The glass transition temperature (the maximum point of a loss elastic modulus in the measurement of dynamic viscoelasticity at 110 Hz) is preferably from 50 to 180° C. for the magnetic layer and from 0 to 180° C. for the non-magnetic layer, respectively. The loss elastic modulus is preferably in the range of from 1×107 to 8×108 Pa (from 1×108 to 8×109 dyne/cm2), and the loss tangent is preferably not more than 0.2. When the loss tangent is too large, adhesive failure is liable to take place. It is preferable that these thermal characteristics or mechanical characteristics are substantially equal within 10% in the respective directions within the plane of the medium. The amount of the residual solvent contained in the magnetic layer is preferably not more than 100 mg/m2, and more preferably not more than 10 mg/m2. The porosity which the coating layer has is preferably not more than 30% by volume, and more preferably not more than 20% by volume in both the non-magnetic layer and the magnetic layer. For the sake of achieving a high output, the porosity is preferably high. However, there may be the case where it is better to ensure a certain value of the porosity depending upon the purpose. For example, in a disc medium in which the repeated application is considered important, a larger porosity is often preferable in view of the running durability. The magnetic layer preferably has a maximum height SRmax of not more than 0.5 μm, a ten-point average roughness SRz of not more than 0.3 μm, a center plane profile peak height SRp of not more than 0.3 μm, a center plane profile valley depth SRv of not more than 0.3 μm, a center plane area rate SSr of from 20 to 80%, an average wavelength Sλa of from 5 to 300 sum. These physical characteristics can be easily controlled by controlling the surface properties by the filler of the polymer support or by the roll surface shape of the calender treatment. The curl is preferably adjusted within ±3 mm. In the case where the magnetic recording medium of the invention is constructed of the non-magnetic layer and the magnetic layer, these physical characteristics can be changed by the non-magnetic layer and the magnetic layer depending upon the purpose. For example, it is possible to improve the tough with a head by making the elastic modulus of the magnetic layer high to enhance the running durability and simultaneously making the elastic modulus of the non-magnetic layer lower than that of the magnetic layer. EXAMPLES The invention will be more specifically described below with reference to the following Examples. Incidentally, the compositions, proportions, operations, orders, etc. as indicated herein can be changed so far as they do not fall outside the spirit of the invention. Also, it should be construed that the invention is never limited to the following Examples. Also, all “parts” used in the Examples mean a part by weight unless otherwise indicated. Examples of the First Embodiment Example 1 Preparation of coating material 1 for magnetic layer: Ferromagnetic acicular metal powder: 100 parts Composition: Fe/Co/Al/Y = 67/20/8/5 Surface treated layer: Al2O3, Y2O3 Coercive force (Hc): 183 kA/m Crystallite size: 12.5 nm Average major axis length: 45 nm Average acicular ratio: 6 BET specific surface area (SBET): 46 m2/g Saturation magnetization (σs): 140 A · m2/kg Polyurethane resin: 12 parts Branched chain-containing polyester polyol/ diphenylmethane diisocyanate based resin, polar group: —SO3Na = 70 eq/ton (content) Phenylphosphonic acid: 3 parts α-Al2O3 (mean grain size: 0.06 μm): 2 parts Carbon black (mean grain size: 20 nm): 2 parts Cyclohexanone: 110 parts Methyl ethyl ketone: 100 parts Toluene: 100 parts Butyl stearate: 2 parts Stearic acid: 1 part Preparation of coating material 1 for non-magnetic layer: Non-magnetic inorganic metal powder: 85 parts α-Iron oxide Surface treated layer: Al2O3, SiO2 Average major axis length: 0.15 nm Tap density: 0.8 g/mL Average acicular ratio: 7 SBET: 52 m2/g pH: 8 DBP oil absorption: 33 mL/100 g Carbon black: 20 parts DBP oil absorption: 120 mL/100 g pH: 8 SBET: 250 m2/g Volatile matter content: 1.5% Polyurethane resin: 12 parts Branched chain-containing polyester polyol/ diphenylmethane diisocyanate based resin, polar group: —SO3Na = 70 eq/ton (content) Acrylic resin: 6 parts Benzyl methacrylate/diacetone acrylamide based resin, polar group: —SO3Na = 60 eq/ton (content) Phenylphosphonic acid: 3 parts α-Al2O3 (mean grain size: 0.2 μm): 1 part Cyclohexanone: 140 parts Methyl ethyl ketone: 170 parts Butyl stearate: 2 parts Stearic acid: 1 part With respect to each of the foregoing coating material 1 for magnetic layer and coating material 1 for non-magnetic layer, the respective components were kneaded in an open kneader for 60 minutes and then dispersed in a sand mill for 120 minutes. To each of the resulting dispersion liquids, 6 parts of a trifunctional low-molecular weight polyisocyanate compound (Coronate 3041, manufactured by Nippon Polyurethane Industry Co., Ltd.) was added, and the mixture was further mixed with stirring for 20 minutes. The resulting mixture was filtered using a filter having a mean pore size of 1 μm to prepare a magnetic coating material 1 and a non-magnetic coating material 1. On a previously corona-treated polyethylene terephthalate support having a thickness of 7 μm and an intrinsic viscosity of 0.47 dL/g and composed of two layers, in which the magnetic layer coating surface (A surface) and the back surface (B surface) against the magnetic layer coating surface had a roughness (SRa) of 3.0 nm and 8.0 nm, respectively, the foregoing coating material liquid for non-magnetic layer was dried in a thickness after drying of 1.5 μm, and immediately thereafter, the coating material liquid for magnetic layer was subjected to simultaneous multilayer-coating in a thickness after drying of 0.1 μm. The sample was subjected to magnetic field orientation using a 300-mT magnet in the state where the magnetic layer and the non-magnetic layer were still wet. After drying, the sample was further subjected to a surface smoothening treatment using a 7-stage calender constructed only of a metal roll at a speed of 100 m/min, a linear pressure of 300 kg/cm (294 kN/m) and a temperature of 90° C. Thereafter, a back layer having a thickness of 0.5 μm (prepared by dispersing 100 parts of carbon black having a mean grain size of 17 nm, 80 parts of calcium carbonate having a mean grain size of 40 nm, and 5 parts of α-alumina having a mean grain size of 200 nm in a nitrocellulose resin, a polyurethane resin and a polyisocyanate) was coated. Thereafter, the sample was heat treated at 70° C. for 48 hours and slit into a width of ½ inch to prepare a magnetic tape. Examples 2 to 3 and 4 to 7 Respective magnetic tapes were prepared in the same manner as in Example 1, except for changing the polyethylene terephthalate support (polymer support) as shown in Table 1. Example 4 A magnetic tape was prepared in the same manner as in Example 3, except for using a coating material for forming a magnetic layer or a non-magnetic layer as prepared using the following coating material 2 for magnetic layer and coating material 2 for non-magnetic layer in place of the coating material 1 for magnetic layer and the coating material 1 for non-magnetic layer, respectively. Coating material 2 for magnetic layer (hexagonal ferrite): Barium ferrite magnetic powder (average tabular 100 parts diameter: 30 nm) Vinyl chloride based copolymer: 6 parts MR555 (manufactured by Zeon Corporation) polyurethane resin: 3 parts UR8200 (manufactured by Toyobo Co., Ltd.) α-Alumina (mean grain size: 0.3 μm): 2 parts HIT55 (manufactured by Sumitomo Chemical Co., Ltd.) Carbon black (mean grain size: 0.015 μm): 5 parts #55 (manufactured by Asahi Carbon Co., Ltd.) Butyl stearate: 1 part Stearic acid: 2 parts Methyl ethyl ketone: 125 parts Cyclohexanone: 125 parts Coating material 2 for non-magnetic layer: Non-magnetic powder, αFe2O3 (hematite): 80 parts (Average major axis length: 0.15 μm, specific surface area by the BET method: 52 m2/g, pH: 8, tap density: 0.8, DBP oil absorption: 27 to 38 mL/100 g, surface coating compound: Al2O3, SiO2) Carbon black: 20 parts (Mean grain size: 16 nm, DBP oil absorption: 80 mL/100 g, pH: 8.0, specific surface area by the BET method: 250 m2/g, volatile matter content: 1.5%) Vinyl chloride based copolymer: 12 parts (MR-110, manufactured by Zeon Corporation) Polyester polyurethane resin: 5 parts α-Al2O3 (mean grain size: 0.2 μm): 1 part Butyl stearate: 1 part Stearic acid: 1 part Methyl ethyl ketone: 100 parts Cyclohexanone: 50 parts Toluene: 50 parts With respect to each of the foregoing coating material 2 for magnetic layer and coating material 2 for non-magnetic layer, the respective components were kneaded in a kneader and then dispersed in a sand mill for 4 hours. To each of the resulting dispersion liquids, 3 parts of a polyisocyanate was added. Further, 40 parts of cyclohexanone was added to each of the mixture, followed by filtration using a filter having a mean pore size of 1 μm to prepare a coating liquid for forming the magnetic layer and a coating liquid for forming the non-magnetic layer. Comparative Examples 1 to 4 Magnetic tapes of Comparative Examples 1 to 4 were prepared in the same manner as in Example 1, except for changing the polyethylene terephthalate as shown in Table 1. The performance of the resulting samples was evaluated in the following manners. The results obtained are shown in Table 1. <Measurement Method> 1. Measurement of intrinsic viscosity of polymer support: The polymer support was dissolved in a mixed solvent of phenol/1,1,2,2-tetrachloroethane (weight ratio: 60/40), and its intrinsic viscosity was measured at 25° C. using an automatic viscometer having an Ubbelohde's viscometer set therein. 2. Measurement of tensile characteristics (Young's modulus and breaking strength) of polymer support: The Young's modulus and breaking strength were measured at a specimen length of 100 mm, a width of 5 mm and a drawing rate of 100 mm/min under the circumstance at 25° C. and 50% RH using a Strograph V1-C model tensile tester manufactured by Toyo Seiki Seisaku-sho, Ltd. according the method defined in JIS K7113 (1995). 3. Measurement of contact stylus three-dimensional surface roughness (SRa) of polymer support by contact stylus three-dimensional surface roughness analyzer: The SRa (of the A surface and the B surface) was measured using a contact stylus surface roughness measuring instrument manufactured by Kosaka Laboratory Ltd. according to JIS B06101. 4. Measurement of amount of edge debris: The resulting tape was run with 200 passes over the overall length under the circumstance at 5° C. and 80% RH, and after completion of running, the presence of a stain of the head was judged. The case where no stain was observed is defined as “◯”; the case where stains were slightly observed but did not affect the recording and reproducing head portions is defined as “Δ”; and the case where stains adhered even to the recording and reproducing head portions is defined as “x”. 5. Error rate (at the initial stage and after the preservation): Using a magnetic tape immediately after the production, a recording signal was recorded and reproduced at 25° C. and 50% RH in an 8-10 conversion PI equalization mode, thereby measuring the error rate (at the initial stage). Using a magnetic tape immediately after the production, a recording signal was recorded in the same manner as described previously, preserved in the circumstance at 25° C. and 50% RH for one week, and then reproduced, thereby measuring the error rate (after the preservation). TABLE 1 Polymer support Intrinsic Surface roughness (SRa) Young's modulus Breaking strength viscosity Thickness A surface B surface MD TD MD TD No. dL/g μm nm nm GPa GPa MPa Mpa Example 1 0.47 7.0 3.0 8.0 7.9 6.0 450 380 Example 2 0.49 7.0 3.0 8.0 7.8 6.2 469 406 Example 3 0.49 4.5 3.0 8.0 7.8 6.2 469 406 Example 4 0.49 4.5 3.0 8.0 7.8 6.2 469 406 Example 5 0.49 7.0 3.0 8.0 8.2 5.8 499 384 Example 6 0.49 7.0 3.0 8.0 7.0 7.0 429 450 Example 7 0.51 7.0 3.0 8.0 7.8 6.2 493 421 Comparative 0.45 7.0 3.0 8.0 6.7 7.0 366 419 Example 1 Comparative 0.50 7.0 3.0 8.0 6.8 7.1 431 463 Example 2 Comparative 0.50 7.0 3.0 8.0 5.4 13.4 361 560 Example 3 Comparative 0.52 7.0 3.0 8.0 8.8 5.9 547 367 Example 4 Ferromagnetic powder Evaluation results Average major axis length or Error rate average tabular diameter At the initial stage After the preservation No. Type Nm Edge debris ×10−5 ×10−5 Example 1 Fe alloy 45 ◯ 0.10 0.13 Example 2 Fe alloy 45 ◯ 0.11 0.15 Example 3 Fe alloy 45 ◯ 0.13 0.16 Example 4 BaFe 30 ◯ 0.12 0.15 Example 5 Fe alloy 45 ◯ 0.09 0.16 Example 6 Fe alloy 45 ◯ 0.15 0.19 Example 7 Fe alloy 45 ◯ 0.10 0.15 Comparative Fe alloy 45 Δ 0.18 1.58 Example 1 Comparative Fe alloy 45 X 0.17 1.43 Example 2 Comparative Fe alloy 45 X 0.24 3.56 Example 3 Comparative Fe alloy 45 X 0.16 1.56 Example 4 According to the Examples of the first embodiment of the invention, the Examples are extremely small in the amount of edge debris and low in the error rate at the initial stage and after the preservation. On the other hand, the Comparative Examples are large in the amount of edge debris and high in the error rate at the initial stage and after the preservation. Thus, the invention gives rise to marked effects as compared with the conventional method. Examples of the Second Embodiment Example 8 Preparation of coating material 1 for magnetic layer: Ferromagnetic acicular metal powder: 100 parts Composition: Fe/Co/Al/Y = 67/20/8/5 Surface treated layer: Al2O3, Y2O3 Coercive force (Hc): 183 kA/m Crystallite size: 12.5 nm Average major axis length: 45 nm Average acicular ratio: 6 BET specific surface area (SBET): 46 m2/g Saturation magnetization (σs): 140 A · m2/kg Polyurethane resin: 12 parts Branched chain-containing polyester polyol/ diphenylmethane diisocyanate based resin, polar group: —SO3Na = 70 eq/ton (content) Phenylphosphonic acid: 3 parts α-Al2O3 (mean grain size: 0.06 μm): 2 parts Carbon black (mean grain size: 20 nm): 2 parts Cyclohexanone: 110 parts Methyl ethyl ketone: 100 parts Toluene: 100 parts Butyl stearate: 2 parts Stearic acid: 1 part Preparation of coating material 1 for non-magnetic layer: Non-magnetic inorganic metal powder: 85 parts α-Iron oxide Surface treated layer: Al2O3, SiO2 Average major axis length: 0.15 nm Tap density: 0.8 g/mL Average acicular ratio: 7 SBET: 52 m2/g pH: 8 DBP oil absorption: 33 mL/100 g Carbon black: 20 parts DBP oil absorption: 120 mL/100 g pH: 8 SBET: 250 m2/g Volatile matter content: 1.5% Polyurethane resin: 12 parts Branched chain-containing polyester polyol/ diphenylmethane diisocyanate based resin, polar group: —SO3Na = 70 eq/ton (content) Acrylic resin: 6 parts Benzyl methacrylate/diacetone acrylamide based resin, polar group: —SO3Na = 60 eq/ton (content) Phenylphosphonic acid: 3 parts α-Al2O3 (mean grain size: 0.2 μm): 1 parts Cyclohexanone: 140 parts Methyl ethyl ketone: 170 parts Butyl stearate: 2 parts Stearic acid: 1 part With respect to each of the foregoing coating material 1 for magnetic layer and coating material 1 for non-magnetic layer, the respective components were kneaded, in an open kneader for 60 minutes and then dispersed in a sand mill for 120 minutes. To each of the resulting dispersion liquids, 6 parts of a trifunctional low-molecular weight polyisocyanate compound (Coronate 3041, manufactured by Nippon Polyurethane Industry Co., Ltd.) was added, and the mixture was further mixed with stirring for 20 minutes. The resulting mixture was filtered using a filter having a mean pore size of 1 μm to prepare a magnetic coating material 1 and a non-magnetic coating material 1. On a previously corona-treated polyethylene terephthalate support having a thickness of 6.9 μm, an Mn of 14,000 and an Mw of 33,000 and composed of two layers, in which the magnetic layer coating surface (A surface) and the back surface (B surface) against the magnetic layer coating surface had a roughness (SRa) of 3.2 nm and 7.6 nm, respectively, the foregoing coating material liquid for non-magnetic layer was dried in a thickness after drying of 1.5 μm, and immediately thereafter, the coating material liquid for magnetic layer was subjected to simultaneous multilayer-coating in a thickness after drying of 0.1 μm. The sample was subjected to magnetic field orientation using a 300-mT magnet in the state where the magnetic layer and the non-magnetic layer were still wet. After drying, the sample was further subjected to a surface smoothening treatment using a 7-stage calender constructed only of a metal roll at a speed of 100 m/min, a linear pressure of 300 kg/cm (294 kN/m) and a temperature of 90° C. Thereafter, a back layer having a thickness of 0.5 μm (prepared by dispersing 100 parts of carbon black having a mean grain size of 17 nm, 80 parts of calcium carbonate having a mean grain size of 40 nm, and 5 parts of α-alumina having a mean grain size of 200 nm in a nitrocellulose resin, a polyurethane resin and a polyisocyanate) was coated. Thereafter, the sample was heat treated at 70° C. for 48 hours and slit into a width of ½ inch to prepare a magnetic tape. Examples 9 to 11 Respective magnetic tapes were prepared in the same manner as in Example 8, except for changing the polyethylene terephthalate support (polymer support) as shown in Table 2. Example 10 A magnetic tape was prepared in the same manner as in Example 9, except for using a coating material for forming a magnetic layer or a non-magnetic layer as prepared using the following coating material 2 for magnetic layer and coating material 2 for non-magnetic layer in place of the coating material 1 for magnetic layer and the coating material 1 for non-magnetic layer, respectively. Coating material 2 for magnetic layer (hexagonal ferrite): Barium ferrite magnetic powder (average tabular 100 parts diameter: 30 nm): Vinyl chloride based copolymer: 6 parts MR555 (manufactured by Zeon Corporation) Polyurethane resin: 3 parts UR8200 (manufactured by Toyobo Co., Ltd.) α-Alumina (mean grain size: 0.3 μm): 2 parts HIT55 (manufactured by Sumitomo Chemical Co., Ltd.) Carbon black (mean grain size: 0.015 μm): 5 parts #55 (manufactured by Asahi Carbon Co., Ltd.) Butyl stearate: 1 part Stearic acid: 2 parts Methyl ethyl ketone: 125 parts Cyclohexanone: 125 parts Coating material 2 for non-magnetic layer: Non-magnetic powder, αFe2O3 (hematite): 80 parts (Average major axis length: 0.15 μm, specific surface area by the BET method: 52 m2/g, pH: 8, tap density: 0.8, DBP oil absorption: 27 to 38 Ml/100 g, surface coating compound: Al2O3, SiO2) Carbon black: 20 parts (Mean grain size: 16 nm, DBP oil absorption: 80 mL/100 g, pH: 8.0, specific surface area by the BET method: 250 m2/g, volatile matter content: 1.5%) Vinyl chloride based copolymer: 12 parts (MR-110, manufactured by Zeon Corporation) Polyester polyurethane resin: 5 parts α-Al2O3 (mean grain size: 0.2 μm): 1 part Butyl stearate: 1 part Stearic acid: 1 part Methyl ethyl ketone: 100 parts Cyclohexanone: 50 parts Toluene: 50 parts With respect to each of the foregoing coating material 2 for magnetic layer and coating material 2 for non-magnetic layer, the respective components were kneaded in a kneader and then dispersed in a sand mill for 4 hours. To each of the resulting dispersion liquids, 3 parts of a polyisocyanate was added. Further, 40 parts of cyclohexanone was added to each of the mixture, followed by filtration using a filter having a mean pore size of 1 μm to prepare a coating liquid for forming the magnetic layer and a coating liquid for forming the non-magnetic layer. Comparative Examples 5 to 8 Magnetic tapes of Comparative Examples 5 to 8 were prepared in the same manner as in Example 8, except for changing the polyethylene terephthalate as shown in Table 2. The performance of the resulting samples was evaluated in the following manners. The results obtained are shown in Table 2. <Measurement Method> 1. Measurement of Mn and Mw of polymer support: The polymer support was dissolved in hexafluoroisopropanol (HFIP), and the Mn and Mw of the polymer support were determined from a calibration curve prepared using polymethyl methacrylate (PMMA) having a known molecular weight in GPC, HLC-8220 manufactured by Tosoh Corporation (column construction: Super HM-M×2, column vessel temperature: 40° C.) while using the same HFIP as an eluting solution. 2. Measurement of tensile characteristics (Young's modulus and breaking strength) of polymer support: The Young's modulus and breaking strength were measured at a specimen length of 100 mm, a width of 5 mm and a drawing rate of 100 mm/min under the circumstance at 25° C. and 50% RH using a Strograph V1-C model tensile tester manufactured by Toyo Seiki Seisaku-sho, Ltd. according the method defined in JIS K7113 (1995). 3. Measurement of contact stylus three-dimensional surface roughness (SRa) of polymer support by contact stylus three-dimensional surface roughness analyzer: The SRa (of the A surface and the B surface) was measured using a contact stylus surface roughness measuring instrument manufactured by Kosaka Laboratory Ltd. according to JIS B06101. 4. Measurement of amount of edge debris: The resulting tape was run with 200 passes over the overall length under the circumstance at 5° C. and 80% RH, and after completion of running, the presence of a stain of the head was judged. The case where no stain was observed is defined as “◯”; the case where stains were slightly observed but did not affect the recording and reproducing head portions is defined as “Δ”; and the case where stains adhered even to the recording and reproducing head portions is defined as “x”. 5. Error rate (at the initial stage and after the preservation): Using a magnetic tape immediately after the production, a recording signal was recorded and reproduced at 25° C. and 50% RH in an 8-10 conversion PI equalization mode, thereby measuring the error rate (at the initial stage). Using a magnetic tape immediately after the production, a recording signal was recorded in the same manner as described previously, preserved in the circumstance at 25° C. and 50% RH for one week, and then reproduced, thereby measuring the error rate (after the preservation). TABLE 2 Polymer support Surface Molecular weight roughness (SRa) Young's modulus Number average Weight average Thickness A surface B surface MD TD No. Mn Mw μm nm nm GPa GPa Example 8 14000 33000 6.9 3.2 7.6 7.8 6.0 Example 9 16000 37000 6.9 3.2 7.6 7.9 6.2 Example 10 16000 37000 6.9 3.2 7.6 7.9 6.2 Example 11 18000 39000 6.9 3.2 7.6 8.0 6.4 Comparative 8000 20000 6.9 3.2 7.6 6.6 6.9 Example 5 Comparative 10000 25000 6.9 3.2 7.6 6.8 7.1 Example 6 Comparative 16000 37000 6.9 3.2 7.6 6.9 7.3 Example 7 Comparative 20000 42000 6.9 3.2 7.6 8.0 6.6 Example 8 Ferromagnetic powder Evaluation results Average major axis length or Error rate average tabular diameter At the initial stage At the preservation No. Type Nm Edge debris ×10−5 ×10−5 Example 8 Fe alloy 45 ◯ 0.09 0.12 Example 9 Fe alloy 45 ◯ 0.12 0.17 Example 10 BaFe 30 ◯ 0.11 0.16 Example 11 Fe alloy 45 ◯ 0.14 0.19 Comparative Fe alloy 45 X 0.25 2.59 Example 5 Comparative Fe alloy 45 X 0.28 3.83 Example 6 Comparative Fe alloy 45 X 0.23 3.66 Example 7 Comparative Fe alloy 45 Δ 0.22 1.56 Example 8 According to the Examples of the second embodiment of the invention, the Examples are extremely small in the amount of edge debris and low in the error rate at the initial stage and after the preservation. On the other hand, the Comparative Examples are large in the amount of edge debris and high in the error rate at the initial stage and after the preservation. Thus, the invention gives rise to marked effects as compared with the conventional method. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Technical Field of the Invention The present invention relates to a magnetic recording medium comprising a polymer support having thereon a magnetic layer containing a ferromagnetic powder and a binder and further to a magnetic recording medium having an excellent electromagnetic conversion characteristic and reliability. 2. Description of the Related Art In the magnetic recording field, putting digital recording which is small in deterioration of recording to practical use is developing in place of the conventional analog recording. In recording and reproducing equipment and magnetic recording media which are used in digital recording, not only high image quality and high sound quality, but also miniaturization and space reduction are required. However, in general, since much signal recording is necessary in the digital recording as compared with the analog recording, the digital recording is required to realize recording with a higher density. In recent years, a reproducing head applying magnetic resistance (MR) as an actuation principle was proposed and began to be used in a hard disc, etc. Also, JP-A-8-227517 proposes to apply the reproducing head to a magnetic tape. In an MR head, since a reproducing output of several times as compared with an induction type magnetic head is obtained and an induction coil is not used, by largely lowering noises of instruments such as an impedance noise to lower a noise of a magnetic recording medium, it becomes possible to obtain a large SN ratio. In other words, if the noise of the magnetic recording medium hidden in a conventional instrument is made small, good recording and reproduction can be achieved, and a high-density recording characteristic can be greatly improved. So far, in magnetic recording media, ones comprising a support having thereon a magnetic layer having Co-modified iron oxide, CrO 2 , a ferromagnetic metal powder, or a hexagonal ferrite powder dispersed in a binder are widely used. For the sake of reducing the noise, various measures may be considered. In particular, it is effective to decrease the size of a grain of the ferromagnetic powder. In recent magnetic materials, ferromagnetic metal fine powders having an average major axis length of not more than 100 nm are used, thereby enhancing the effect. In order to achieve the foregoing high-density recording, it is necessary to realize shorter the wavelength of a recording signal or to make the recording tracks narrow. For achieving this, in addition to realization of fine division of a ferromagnetic powder, high packing and ultra-smoothening of the surface of a magnetic recording medium, it is required to make a magnetic recording medium thin for the purpose of improving the volume density. In general, a coating type magnetic recording medium has a structure in which a magnetic layer is provided on a support, or a non-magnetic layer and a magnetic layer are provided in this order on a support. For the sake of making the foregoing magnetic recording medium thin, it is required to make not only the magnetic layer but also the whole of layers constructing the magnetic recording medium thin. For the purpose of making the thickness of the magnetic recording medium thin, it has hitherto been carried out to make the support thin or to make the non-magnetic layer thin. However, if the support is made thin exceeding a certain range, the running durability is lowered; and if the non-magnetic layer is made thin, a lowering of the output, an increase of the error rate, and an increase of the dropout are introduced. That is, if thinning of the magnetic recording medium advances for the purpose of increasing the recording density, a sufficient leveling effect against the support is not obtained in the magnetic layer, and the surface state of the support provided beneath the magnetic layer largely influences the surface of the magnetic layer. It may be considered that the principal cause resides in very small protrusions (so-called fish eyes) scattered on the surface of the support; the fish eyes become an anti-blocking filler, thereby lifting up the surface of the magnetic layer to form protrusions; and the dropout is generated due to these protrusions. In particular, in a linear recording system, since a magnetic tape runs substantially in parallel to a magnetic head and comes into contact with the head, the dropout caused due to protrusions present on the surface of the magnetic layer is liable to be generated. In order to prevent the dropout caused by the foregoing protrusions on the magnetic layer, it is necessary to change the filler contained in the support and smoothen the surface of the support. However, if the filler contained in the support is changed, the film formation step of a support, the production step of a magnetic recording medium, and the running properties within a drive after forming a tape are greatly influenced, and therefore, it cannot be said that this is an effective method. For this reason, a support having two or more layers in which the surface properties are made different between the side of the support at which a magnetic layer is provided and the side of the back surface against the former. Further, it is known that even if the support, especially the surface of the magnetic layer is smoothened, a stain is accumulated on the head, resulting in the occurrence of dropout. This is caused by the matter that an edge debris formed when an end face of the support is shaven by a running system within the drive is accumulated, and this end face is generated by slitting. Now, for the purpose of preventing a poor pancake shape from the occurrence by preventing a high edge of an end portion generated in the slitting step, JP-A-8-45060 describes a magnetic recording medium using a support made of polyethylene naphthalate having a thickness of 4 μm or more and regulated so as to have a ratio of the Young's modulus in the machine direction to the Young's modulus in the transverse direction of from 0.4 to 1.5 and a viscosity of from 0.45 to 0.53. The foregoing definition of the physical properties of the support is extremely broad and unclear. Also, only the foregoing definition is insufficient as a support for the recent magnetic recording media having an improved recording density. Since this JP-A-8-45060 discloses neither unit nor measurement method regarding the density, its invention is obscure. Also, with respect to the raw material of the support to be used, only the polyethylene naphthalate is described, but no description regarding its layer construction and surface properties is given. As described above, according to the conventional supports, it is difficult to provide a magnetic recording medium adapted for the recent demand of high recording density. | <SOH> SUMMARY OF THE INVENTION <EOH>An object of the invention is to provide a magnetic recording medium which does not form an edge debris and can effectively prevent an increase of the error rate while meeting stable running properties. The means for solving the foregoing problems are as follows. (1) A magnetic recording medium comprising a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having an intrinsic viscosity of from 0.47 to 0.51 dL/g, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa, and a breaking strength in the transverse direction of from 370 to 450 MPa. (2) The magnetic recording medium as set forth above in (1), wherein the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least two layers, in which a contact stylus three-dimensional surface roughness SRa(A) of the surface (A surface) in the side at which the magnetic layer is provided is from 1 to 6 nm, and a contact stylus three-dimensional surface roughness SRa(B) of the back surface (B surface) against the A surface is from 6 to 10 nm, with SRa(A) and SRa(B) being satisfied with the relationship of [SRa(A)<SRa(B)]. (3) A magnetic recording medium comprising a polymer support having thereon at least one magnetic layer containing a ferromagnetic metal powder having an average major axis length of from 20 to 100 nm or a ferromagnetic hexagonal ferrite powder having an average tabular diameter of from 5 to 40 nm and a binder, the polymer support having a number average molecular weight (Mn) of from 12,000 to 18,000, a weight average molecular weight (Mw) of from 32,000 to 40,000, a Young's modulus in the machine direction of from 7.0 to 8.6 GPa, and a Young's modulus in the transverse direction of from 5.4 to 8.0 GPa. (4) The magnetic recording medium as set forth above in (3), wherein the polymer support is a laminated polyester film having a thickness of not more than 8 μm and comprising at least two layers, in which a contact stylus three-dimensional surface roughness SRa(A) of the surface (A surface) in the side at which the magnetic layer is provided is from 1 to 6 nm, and a contact stylus three-dimensional surface roughness SRa(B) of the back surface (B surface) against the A surface is from 6 to 10 nm, with SRa(A) and SRa(B) being satisfied with the relationship of [SRa(A)<SRa(B)]. The invention can provide a magnetic recording medium capable of keeping a good error rate without forming an edge debris by controlling the physical properties of a polymer support, i.e., an intrinsic viscosity or Mn and Mw and Young's moduli in the machine direction and transverse direction. detailed-description description="Detailed Description" end="lead"? | 20050119 | 20080506 | 20050915 | 90046.0 | 0 | FALASCO, LOUIS V | MAGNETIC RECORDING MEDIUM | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,069 | ACCEPTED | Photographing apparatus, method and program | Processing for judging whether a face is included in a frame is performed, in a predetermined interval, on each of frames included in a moving image of a subject, displayed on a monitor, until the judgment becomes positive. If it is judged that a face is included in a frame, the facial position is detected in the frame, and stored. Then, judgment is made as to whether a face is included in the next frame after predetermined time. If the judgment is positive, the facial position is detected. The previously stored facial position is replaced by the newly detected facial position, and the newly detected facial position is stored. These processes are repeated until photographing operation is performed by operating a release unit. | 1. A photographing apparatus comprising: a photographing means for obtaining image data by taking a photograph of a subject; a display means for displaying various kinds of information including the image data; a release means for performing photographing operation; a storage means for storing various kinds of information including the image data; a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means; a face judgment means for performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; a face detection means for detecting a facial position in a frame, which is judged to include a face, if the face judgment means judges that the face is included in the frame; and a control means for controlling the photographing means, the face judgment means, the face detection means, and the storage means so that the detected facial position is stored in the storage means, judgment is made as to whether the face is included in the next frame after the predetermined time, and if the judgment is positive, the facial position is detected, the facial position, which is stored in the storage means, is replaced by the newly detected facial position and the newly detected facial position is stored in the storage means, and until the release means performs the photographing operation, judgment is made as to whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, the facial position is detected, and the newly detected facial position is stored in the storage means, and a frame obtained when the release means performs the photographing operation and/or a plurality of temporally precedent and/or subsequent frames of the obtained frame are stored in the storage means as the image data. 2. A photographing apparatus as defined in claim 1, further comprising: a variation judgment means for referring to the frame, which was judged to include the face, and its next frame, thereby judging whether the variation in an image between the two frames exceeds a predetermined value, wherein the control means is a means for controlling the face judgment means so that if the variation judgment means judges that the variation is less than or equal to the predetermined value, the face judgment means performs processing, only on the region, including the facial position stored in the storage means, and the vicinity of the facial position, to judge whether the face is included in the next frame, and if the variation judgment means judges that the variation exceeds the predetermined value, the face judgment means performs processing, on the whole region of the next frame, to judge whether the face is included in the next frame. 3. A photographing apparatus as defined in claim 2, wherein the variation is one of the absolute value of the difference in the average value of pixel values in an image between the two frames and the difference in the histogram shape of the image between the two frames. 4. A photographing apparatus as defined in claim 1, further comprising: an image processing means for performing predetermined image processing, related to a face, on the image data by referring to the facial position stored in the storage means after the photographing operation is performed. 5. A photographing apparatus as defined in claim 4, wherein the image processing means is a means for performing at least one of red-eye correction processing, noise suppression processing on the region of the image representing a face, density correction processing, and gradation correction processing as the predetermined image processing. 6. A photographing apparatus as defined in claim 4, wherein the image processing means is a means for performing processing for judging whether the eyes in the detected face are closed, and if the eyes are closed, selecting a frame including a face with open eyes from the temporally precedent and/or subsequent frames of the frame, which was obtained when the photographing operation was performed, as the predetermined image processing. 7. A photographing apparatus as defined in claim 4, wherein the image processing means is a means for performing processing for judging whether the detected face is a smiling face, and if it is not the smiling face, selecting a frame including a smiling face from the temporally precedent and/or subsequent frames of the frame, which was obtained when the photographing operation was performed, as the predetermined image processing. 8. A photographing apparatus as defined in claim 1, wherein the face judgment means is a means for performing the judgment by using reference data, obtained by learning by a machine learning technique. 9. A photographing apparatus as defined in claim 1, wherein the photographing apparatus is a digital camera. 10. A photographing method at a photographing apparatus including a photographing means for obtaining image data by taking a photograph of a subject, a display means for displaying various kinds of information including the image data, a release means for performing photographing operation, a storage means for storing various kinds of information including the image data, and a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means, the method comprising the steps of: performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; detecting a facial position in a frame, which is judged to include a face, if it is judged that the face is included in the frame; and storing the detected facial position in the storage means, judging whether the face is included in the next frame after the predetermined time, and if the judgment is positive, detecting the facial position, replacing the facial position, which is stored in the storage means, by the newly detected facial position and storing the newly detected facial position in the storage means, and until the release means performs the photographing operation, judging whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, detecting the facial position, and storing the newly detected facial position in the storage means, and storing a frame, which is obtained when the release means performs the photographing operation and a plurality of temporally precedent and/or subsequent frames of the obtained frame in the storage means as the image data. 11. A program for causing a computer to execute an image processing method at a photographing apparatus including a photographing means for obtaining image data by taking a photograph of a subject, a display means for displaying various kinds of information including the image data, a release means for performing photographing operation, a storage means for storing various kinds of information including the image data, and a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means, the program comprising the procedures for: performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; detecting a facial position in a frame, which is judged to include a face, if it is judged that the face is included in the frame; and storing the detected facial position in the storage means, judging whether the face is included in the next frame after the predetermined time, and if the judgment is positive, detecting the facial position, replacing the facial position, which is stored in the storage means, by the newly detected facial position and storing the newly detected facial position in the storage means, and until the release means performs the photographing operation, judging whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, detecting the facial position, and storing the newly detected facial position in the storage means, and storing a frame, which is obtained when the release means performs the photographing operation and/or a plurality of temporally precedent and/or subsequent frames of the obtained frame in the storage means as the image data. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographing apparatus, such as a digital camera, for obtaining image data by taking a photograph and storing the obtained image data in a storage means such as a memory card. The present invention also relates to a photographing method for the photographing apparatus and a program for causing a computer to execute the photographing method. 2. Description of the Related Art Conventionally, when a photograph of a person is taken using a strobe (an electronic flash), there is a problem that the person's eyes glow red or gold in the photograph. This is a so-called red-eye phenomenon. The red-eye phenomenon occurs when strobe light passes through the pupils of the eyes, is reflected at the retinas of the eyes, and the reflected light is captured in a film. Various systems for automatically detecting and correcting the red-eye as described above have been proposed. Particularly, various photographing apparatuses such as digital cameras have been proposed, which correct the red-eye in image data obtained with the digital cameras, by performing correction processing in the digital cameras, (for example, Japanese Unexamined Patent Publication No. 10(1998)-233929, Japanese Unexamined Patent Publication No. 11(1999)-127371, and Japanese Unexamined Patent Publication No. 2000-305141). However, red-eye correction processing requires detection of a human face in an image, represented by the image data, first, and further detection of the positions of the eyes in the detected face. The red-eye correction processing also requires correction processing for changing the color of the eyes from red to black. Since the digital cameras have much lower processing capacity than personal computers, a long time is required for the red-eye correction processing. Hence, there is a problem that the wait time becomes long until performing a next operation, such as displaying an obtained image on a liquid crystal monitor of a digital camera after photographing, or getting the digital camera ready to take a next photograph. SUMMARY OF THE INVENTION In view of the foregoing circumstances, it is an object of the present invention to reduce time for performing image processing on image data when predetermined image processing, such as red-eye correction processing, is performed on the image data in photographing apparatuses such as digital cameras. A photographing apparatus according to the present invention is a photographing apparatus comprising: a photographing means for obtaining image data by taking a photograph of a subject; a display means for displaying various kinds of information including the image data; a release means for performing photographing operation; a storage means for storing various kinds of information including the image data; a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means; a face judgment means for performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; a face detection means for detecting a facial position in a frame, which is judged to include a face, if the face judgment means judges that the face is included in the frame; and a control means for controlling the photographing means, the face judgment means, the face detection means, and the storage means so that the detected facial position is stored in the storage means, judgment is made as to whether the face is included in the next frame after the predetermined time, and if the judgment is positive, the facial position is detected, the facial position, which is stored in the storage means, is replaced by the newly detected facial position and the newly detected facial position is stored in the storage means, and until the release means performs the photographing operation, judgment is made as to whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, the facial position is detected, and the newly detected facial position is stored in the storage means, and a frame obtained when the release means performs the photographing operation and/or a plurality of temporally precedent and/or subsequent frames of the obtained frame are stored in the storage means as the image data. When the photograph is taken with the photographing apparatus such as the digital camera, the moving image of the subject is displayed on the display means until photographing operation is performed by using the release means. The moving image includes 15 to 30 frames per second. Therefore, the “predetermined time” may be set in advance by determining the number of frames included in the predetermined time. For example, the predetermined time may be a time between two temporally adjacent frames, or a time including 5 or 10 frames. The photographing apparatus according to the present invention may further include a variation judgment means for referring to the frame, which was judged to include the face, and its next frame, thereby judging whether the variation in an image between the two frames exceeds a predetermined value, and the control means may be a means for controlling the face judgment means so that if the variation judgment means judges that the variation is less than or equal to the predetermined value, the face judgment means performs processing, only on the region including the facial position stored in the storage means and the vicinity of the facial position, to judge whether the face is included in the next frame, and if the variation judgment means judges that the variation exceeds the predetermined value, the face judgment means performs processing on the whole region of the next frame, to judge whether the face is included in the next frame. The clause “variation in an image between the two frames” refers to the variation, by which whether a scene has been switched between the two frames can be judged. Specifically, the absolute value of the difference in the average value of the pixel values between the two frames, the difference in the shapes of the histograms, or the like may be used as the variation. Here, if a scene is switched between the two frames, the variation in the image between the two frames is relatively large. If a scene is not switched between the two frames, the variation in the image between the two frames is not so large. Therefore, a value, based on which whether the scene has been switched can be discriminated, may be used as the “predetermined value”. The “predetermined value” may be obtained experimentally by calculating the variation between two frames when the scene is actually switched between the two frames. The photographing apparatus according to the present invention may further include an image processing means for performing predetermined image processing, related to a face, on the image data by referring to the facial position, stored in the storage means, after the photographing operation is performed. The “predetermined image processing related to a face” may be any kind of processing as long as the processing is performed on a face, which has been detected in an image represented by image data. For example, the “predetermined image processing related a face” may be processing for improving the image quality of the face, such as at least one of red-eye correction processing, noise suppression processing on the face, density correction processing, and gradation correction processing. Alternatively, the “predetermined image processing related a face” may be processing for judging whether the eyes are closed in the detected face, and if the eyes are closed, selecting a frame including the face with open eyes from temporally preceding and/or subsequent frames of the frame, which was obtained when the photographing operation was performed. The “predetermined image processing related a face” may also be processing for judging whether the detected face is a smiling face, and if it is not a smiling face, selecting a frame including a smiling face from temporally preceding and/or subsequent frames of the frame, which was obtained when the photographing operation was performed. A photographing method according to the present invention is a photographing method for a photographing apparatus including a photographing means for obtaining image data by taking a photograph of a subject, a display means for displaying various kinds of information including the image data, a release means for performing photographing operation, a storage means for storing various kinds of information including the image data, and a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means, the method comprising the steps of: performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; detecting a facial position in a frame, which is judged to include a face, if it is judged that the face is included in the frame; and storing the detected facial position in the storage means, judging whether the face is included in the next frame after the predetermined time, and if the judgment is positive, detecting the facial position, replacing the facial position, which is stored in the storage means, by the newly detected facial position and storing the newly detected facial position in the storage means, and until the release means performs the photographing operation, judging whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, detecting the facial position, and storing the newly detected facial position in the storage means, and storing a frame, which is obtained when the release means performs the photographing operation, and a plurality of temporally precedent and/or subsequent frames of the obtained frame in the storage means as the image data. The photographing method according to the present invention may be provided as a program for causing a computer to execute the photographing method. According to the present invention, the moving image of the subject, which is obtained with the photographing apparatus, is displayed on the display means during photographing. Then, judgment is made, in a predetermined time interval, as to whether a human face is included in the frames forming the moving image until a positive result is obtained in the judgment. If it is judged that a face is included in a frame, the facial position is detected in the frame, which is judged to include the face, and the detected facial position is stored in the storage means. Next, judgment is made as to whether a face is included in a temporally subsequent frame after the predetermined time. If the judgment is YES, the facial position is detected. The facial position, which is stored in the storage means, is replaced by the newly detected facial position, and the newly detected facial position is stored in the storage means. Then, until the release means performs photographing operation, judgment is made as to whether a face is included in the next frame after a predetermined time, and if it is judged that the face is included, the facial position is detected and the newly detected facial position is stored in the storage means. When the release means performs the photographing operation, the frame obtained by photographing and/or a plurality of temporally preceding and/or subsequent frames of the obtained frame are stored in the storage means as image data. Here, when a photograph is taken, after the composition is determined, a few seconds are required before the release means is driven. In many cases, the subject does not move during the few seconds. Therefore, judgment is made, in a predetermined time interval, as to whether a face is included in the frame, and if it is judged that the face is included, the facial position is newly detected and stored in the storage means. Accordingly, the facial position, which is stored in the storage means, corresponds to the facial position included in the image represented by image data, which is obtained by the photographing operation. Hence, when predetermined image processing related to a face is performed on the image data obtained by photographing, face detection processing in the image, represented by the image data, is not required. Accordingly, time required for the image processing can be reduced. Further, the wait time until displaying the image data obtained by photographing on the display means, or time until getting the photographing apparatus ready to take a photograph of the next image can be reduced. Consequently, a photographer can be relieved from stress, which he/she will feel if the wait time is long. Further, the frame, which is judged to include a face, and its next frame are referred to, and judgment is made as to whether the variation in the image between the two frames exceeds a predetermined value. If the variation is less than or equal to the predetermined value, judgment is made as to whether a face is included in the next frame by performing processing only on the region of the next frame, including the facial position stored in the storage means and the vicinity of the facial position. Accordingly, if the scene is not switched between the two frames, it is not required to perform the judgment processing on the whole region of the next frame as to whether the face is included. Therefore, processing time for judging whether a face is included can be reduced. Note that the program of the present invention may be provided being recorded on a computer readable medium. Those who are skilled in the art would know that computer readable media are not limited to any specific type of device, and include, but are not limited to: floppy disks, CD's RAM'S, ROM's, hard disks, magnetic tapes, and internet downloads, in which computer instructions can be stored and/or transmitted. Transmission of the computer instructions through a network or through wireless transmission means is also within the scope of this invention. Additionally, computer instructions include, but are not limited to: source, object and executable code, and can be in any language including higher level languages, assembly language, and machine language. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram illustrating the configuration of a digital camera, which is an embodiment of a photographing apparatus according to the present invention; FIG. 2A is a diagram illustrating an edge detection filter in a horizontal direction; FIG. 2B is a diagram illustrating an edge detection filter in a vertical direction; FIG. 3 is a diagram for explaining calculation of gradient vectors; FIG. 4A is a diagram illustrating a human face; FIG. 4B is a diagram illustrating gradient vectors in the vicinity of the eyes and the mouth of the human face, which is illustrated in FIG. 4A; FIG. 5A is a histogram of the magnitude of the gradient vectors before normalization; FIG. 5B is a histogram of the magnitude of the gradient vectors after normalization; FIG. 5C is a histogram of the quinarized magnitude of the gradient vectors; FIG. 5D is a histogram of the quinarized magnitude of the gradient vectors after normalization; FIG. 6 shows a diagram illustrating examples of sample images, which are recognized as faces; FIG. 7A is a diagram for explaining rotation of a face; FIG. 7B is a diagram for explaining rotation of the face; FIG. 7C is a diagram for explaining rotation of the face; FIG. 8 is a flow chart illustrating learning method of reference data; FIG. 9 is a diagram illustrating a method for obtaining a discriminator; FIG. 10 is a diagram for explaining stepwide deformation of of a frame; FIG. 11 is a diagram for explaining regions, on which processing is performed to judge whether a face is included, when the variation is less than or equal to a threshold value; FIG. 12 is a flow chart (No. 1) illustrating processing in an embodiment of the present invention; FIG. 13 is a flow chart (No. 2) illustrating processing in an embodiment of the present invention; FIG. 14 is a flow chart illustrating processing for judging whether a face is included; FIG. 15A is a diagram for explaining processing for obtaining the difference in shape between histograms as the variation; FIG. 15B is a diagram for explaining processing for obtaining the difference in shape between histograms as the variation; FIG. 15C is a diagram for explaining processing for obtaining the difference in shape between histograms as the variation; and FIG. 16 is a diagram for explaining processing for obtaining temporally preceding and/or subsequent frames of a frame, obtained by photographing operation, as image data. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. FIG. 1 is a schematic block diagram illustrating the configuration of a digital camera, which is an embodiment of a photographing apparatus according to the present invention. As illustrated in FIG. 1, a digital camera 1 includes a photographing unit 10 for forming an image of a subject on a light receiving plane, performing photo-electric conversion on the image, and outputting the image as image data. The digital camera 1 also includes a CPU (central processing unit) 12 for controlling the whole digital camera 1 and performing various kinds of control such as image data sampling timing control, image data recording control, and image data display control. The digital camera 1 also includes an A/D converter 14 for converting analog image data into digital image data. The digital camera 1 also includes an image processing unit 16 for performing image processing such as image resizing, red-eye correction, sharpness correction, gamma correction, contrast correction, and white balance correction. The digital camera 1 also includes a strobe 18, and a strobe control unit 20 for controlling the operation of the strobe 18. The digital camera 1 also includes an input unit 22, used by a user, who is a photographer, when he/she inputs various kinds of information to the digital camera 1. The input unit 22 includes a release button for performing photographing operation and a mode switch for switching the mode of the digital camera 1, such as a photography mode. The digital camera 1 also includes an I/O 24, which is an interface for receiving various kinds of information input at the input unit 22. Further, the digital camera 1 also includes a compression/extraction unit 26 for compressing the image data by using a technique typified by JPEG (Joint Photographic Experts Group) or motion-JPEG compression, and extracting the compressed image data. The digital camera 1 also includes a card interface 32 for converting the image data so that the image data is recorded on a memory card 30, which is mounted in a memory card slot 28 in a detachable manner, and readout from the memory card 30. The memory card 30 is a detachable recording medium typified by a semiconductor memory medium, a magnetic recording medium and a photo recording medium. Further, the digital camera 1 includes a system memory 34 including a ROM (Read-Only Memory) and a RAM (Random Access Memory). Operation programs of the CPU 12, including programs for performing various kinds of processing, and each constant are stored in the ROM. The various kinds of processing are processing for judging whether a face is included in an image represented by image data as described later, and if the judgment is YES, processing for detecting the facial position, and processing for storing the facial position. The RAM is a storage means, which functions as a work area during execution of the programs. The digital camera 1 also includes a timer 36, which is driven during timer photography, and a calendar clock 38 for keeping current time. The digital camera 1 also includes an LCD (Liquid Crystal Display) 40 for displaying various kinds of information such as image data and an LCD control unit 42 for performing D/A conversion or the like for displaying the image data on the LCD 40. The digital camera 1 also includes a frame memory 44 including a VRAM (Video Random Access Memory) or the like, for temporarily storing the image data, which will be displayed by an instruction from the CPU 12. When a photography mode of taking a photograph of the subject by pressing the release button is set, image data of 30 frames per second is input to the frame memory 44. Accordingly, a moving image of the subject is displayed on the LCD 40 during photography. Further, if a user presses the release button to perform a photographing operation while the moving image is displayed on the LCD 40, the CPU 12 performs red-eye correction processing on image data, which was obtained when the photographing operation was performed, and displays the processed image data on the LCD 40. The CPU 12 also records the processed image data on the memory card 30. Then, the CPU 12 reads out the programs for executing processing for judging whether a face is included in the image, processing for detecting the facial position, or the like from the system memory 34, and executes the program. Accordingly, the CPU 12 functions as a photographing control means, a face judgment means, a face detection means, a control means, and a variation judgment means. When the photography mode is set, the CPU 12 executes a program for judging whether a face is included in the image by performing face discrimination processing on a single frame included in the moving image, as described below. Accordingly, the CPU 12 judges whether a face is included in the single frame. The CPU 12 calculates a first characteristic value C1, which is used for discriminating the face, from a single frame Fri. The CPU 12 also calculates a second characteristic value C2 from an image within a facial candidate, extracted from the frame Fri as described later. Specifically, the directions of gradient vectors in the frame Fri are calculated as the first characteristic value C1. Gradient vectors (namely directions and magnitudes) of the image within the facial candidate are calculated as the second characteristic value C2. The calculation of the gradient vectors will be described. First, the CPU 12 performs filtering processing on the frame Fri by using an edge detection filter in a horizontal direction, as illustrated in FIG. 2A, and detects an edge in the frame Fri in the horizontal direction. The CPU 12 also performs filtering processing on the frame Fri by using an edge detection filter in a vertical direction, as illustrated in FIG. 2B, and detects an edge in the frame Fri in the vertical direction. Then, the CPU 12 calculates a gradient vector K at each pixel based on the magnitude H of the edge in the horizontal direction and the magnitude V of the edge in the vertical direction at each pixel of the frame Fri, as illustrated in FIG. 3. Then, the direction of the vector K is obtained as the first characteristic value C1. Specifically, the first characteristic value C1 is represented by a value of 0 to 359 degrees with respect to a predetermined direction (x direction in FIG. 3, for example) of the gradient vector K. When the image is a human face as illustrated in FIG. 4A, in a dark area such as eyes and a mouth, the gradient vectors K calculated as described above are directed to the center of each of the eyes and the mouth, as illustrated in FIG. 4B. In a bright area such as a nose, the gradient vectors K are directed outside from the position of the nose, as illustrated in FIG. 4B. Further, since the density change at the eyes is larger than the density change at the mouth, the magnitudes of the gradient vectors K at the eyes are larger than the magnitudes of the gradient vectors K at the mouth. Here, the second characteristic value C2 is calculated only for the region within the facial candidate. Further, the magnitude of the gradient vector K of the second characteristic value C2 is normalized. This normalization is performed by obtaining a histogram of the magnitudes of the gradient vectors K at all pixels in the facial candidate. The histogram is smoothed so that the magnitudes of the gradient vectors K are evenly distributed to all the range of values, which may represent the magnitude of the gradient vector K at each pixel in the facial candidate (0 to 255 in the case of 8 bits). For example, when the magnitudes of the gradient vectors K are small, and the magnitudes of the gradient vectors K are concentrated in the lower value side of the histogram, as illustrated in FIG. 5A, the magnitudes of the gradient vectors K are normalized so that they are distributed over the whole range of 0 to 255. Accordingly, the magnitudes of the gradient vectors K become distributed in the histogram as illustrated in FIG. 5B. For reducing the operation amount, it is preferable that the distribution range of the histogram of the gradient vectors K is divided into five as illustrated in FIG. 5C, for example, and the frequency distribution is normalized so that the frequency distributions, which are divided into five, are spread to all the range of values from 0 to 255, which are divided into five, as illustrated in FIG. 5D. Here, when a photograph is taken by using the digital camera 1, the brightness of lighting and the direction of lighting differ according to photographing conditions. Therefore, the brightness and direction of lighting in each frame Fri is different. If the gradient vectors K in each of the frames Fri, which are obtained with different brightness and direction of lighting, are calculated in a same manner, even if the image in each of the frames Fri is a face, the calculated magnitudes of the gradient vectors at the positions of the eyes are different in each of the frames. Therefore, it is impossible to accurately discriminate whether the facial candidate is a face. In this case, the magnitudes of the gradient vectors K may be normalized for the whole region of the frame. However, since the operation amount of the normalization is large, normalization processing requires long time. Therefore, in the present embodiment, the second characteristic value is normalized by performing processing only on the facial candidate instead of the whole frame Fri. Accordingly, the operation amount is reduced, and the processing time is shortened. The CPU 12 calculates the first characteristic value C1 and the second characteristic value C2 at each stage of deformation of the frame Fri and the facial candidate, as described later. First reference data R1 and second reference data T2 for discriminating a face is stored in the system memory 34. The first reference data R1 defines a discrimination condition for the combination of the first characteristic value C1 at each pixel included in each of a plurality of kinds of pixel groups including a plurality of pixels, selected from a sample image as described later. The second reference data R2 defines a discrimination condition for the combination of the second characteristic value C2 at each pixel included in each of a plurality of kinds of pixel groups including a plurality of pixels, selected from a sample image. The combination of the first characteristic values C1 and the discrimination condition at each pixel, included in each pixel group, in the first second reference data R1 are determined in advance. The combination of the second characteristic values C2 and the discrimination condition at each pixel, included in each pixel group, in the second reference data R2 are also determined in advance. The combination of the characteristic values C1 and C2 and the discrimination conditions are obtained by learning using a sample image group, including a plurality of sample images, which are recognized as facial images, and a plurality of sample images, which are recognized as non-facial images. In the present embodiment, it is assumed that sample images, which have a size of 30×30 pixels, are used as the sample images, which are recognized as facial images. It is also assumed that the sample images as illustrated in FIG. 6 are used for a single facial image. In the sample images, the distances between the centers of both eyes are 10 pixels, 9 pixels and 11 pixels, and the face is rotated from a standard vertical position on a plane in 3 degree increments in a stepwise manner within the range of ±15 degrees (namely, the rotation angles are −15 degrees, −12 degrees, −9 degrees, −6 degrees, −3 degrees, 0 degrees, 3 degrees, 6 degrees, 9 degrees, 12 degrees, and 15 degrees). Therefore, 3×11=33 sample images are prepared for a single facial image. Here, the positions of the eyes in each of the sample images are the same in the vertical direction when the face is vertically positioned. In FIG. 6, only samples image, which are rotated −15 degrees, 0 degrees and +15 degrees, are illustrated. Further, the center of the rotation is the intersection of diagonal lines in the sample images. It is assumed that, arbitrary images, which have the size of 30×30 pixels, are used as the sample images, which are recognized as non-facial images. Here, if learning is performed by using only a sample image, in which the distance between the centers of both eyes is 10 pixels and the rotation angle on a plane is 0 degrees (namely, the face is vertical), as a sample image, which is recognized as a facial image, the face is discriminated as the facial candidate or the face with reference to the first reference data R1 and the second reference data R2 only in the case the distance between the centers of both eyes is 10 pixels and the face is not rotated at all. The sizes of faces, which may be included in the frame Fri, are not the same. Therefore, for discriminating whether a facial candidate is included in the frame Fri or whether the facial candidate is a face, the frame Fri is enlarged or reduced as described later so that a face, of which the size conforms to the size of the sample image, can be discriminated. However, for accurately changing the distance between the centers of both eyes to 10 pixels, the size of the frame Fri is required to be enlarged or reduced in a stepwise manner by changing the enlargement ratio of the size of the frame Fri in 1.1 units, for example, during discrimination. Therefore, the operation amount becomes huge. Further, the frame Fri may include rotated faces as illustrated in FIGS. 7B and 7C as well as a face, of which rotation angle on a plane is 0 degree, as illustrated in FIG. 7A. However, if only sample images, in which the distance between the centers of the eyes is 10 pixels and the rotation angle of the face is 0 degree, are used for learning, although rotated faces are faces, the rotated faces as illustrated in FIGS. 7B and 7C may not be discriminated. Therefore, in the present embodiment, the sample images as illustrated in FIG. 6 are used as the sample images, which are recognized as facial images. In FIG. 6, the distances between the centers of both eyes are 9 pixels, 10 pixels or 11 pixels, and the face is rotated on a plane in 3 degree increments in a stepwise manner within the range of +15 degrees for each of the distances between the centers of both eyes. Accordingly, the allowable range of the reference data R1 and R2, which are obtained by learning, becomes wide. Accordingly, the frame Fri may be enlarged or reduced in a stepwise manner by changing the enlargement ratio in 11/9 units. Therefore, the operation time can be reduced in comparison with the case of enlarging or reducing the size of the frame Fri in a stepwise manner by changing the enlargement ratio in 1.1 units, for example. Further, the rotated faces as illustrated in FIGS. 7B and 7C may also be discriminated. An example of a learning method by using a sample image group will be described below with reference to a flow chart illustrated in FIG. 8. Here, learning of the second reference data R2 will be described. The sample image group, which is a learning object, includes a plurality of sample images, which are recognized as facial images, and a plurality of sample images, which are recognized as non-facial images. For each sample image, which is recognized as the facial image, images, of which distances between the centers of both eyes are 9 pixels, 10 pixels or 11 pixels, are used. Further, the face in each of the images is rotated on a plane in 3 degree increments in a stepwise manner within the range of ±15 degrees. Weight, namely the degree of importance, is assigned to each of the sample images. First, an initial weight value is equally set to 1 for all of the sample images (step S1). Next, a discriminator is generated for each of a plurality of kinds of pixel groups in the sample images (step S2). Here, each discriminator provides criteria for discriminating a facial image from a non-facial image by using the combination of the second characteristic value C2 at each pixel, which forms a single pixel group. In the present embodiment, a histogram of the combination of the second characteristic value C2 at each pixel, which forms the single pixel group, is used as the discriminator. Generation of the discriminator will be described below with reference to FIG. 9. As illustrated in the sample images in the left side of FIG. 9, a pixel group for generating the discriminator includes a pixel P1 at the center of the right eye, a pixel P2 in the right cheek, a pixel P3 in the forehead and a pixel P4 in the left cheek in each of a plurality of sample images, which are recognized as facial images. Then, the combinations of the second characteristic values C2 at all of the pixels P1-P4 are obtained for all of the sample images, which are recognized as facial images, and a histogram of the combinations of the characteristic values is generated. Here, the second characteristic value C2 represents the direction and magnitude of the gradient vector K. The direction of the gradient vector K can be represented by 360 values of 0 to 359, and the magnitude of the gradient vector K can be represented by 256 values of 0 to 255. Therefore, if all the values, which represent the direction, and the values, which represent the magnitude, are used, the number of combinations is 360×256 for a pixel, and the number of combinations is (360×256)4 for the four pixels. Therefore, a huge number of samples, long time and a large memory are required for learning and detecting. Therefore, in the present embodiment, the values of the directions of the gradient vectors, which are from 0 to 359, are quarternarized. The values from 0 to 44 and from 315 to 359 (right direction) are represented by the value of 0, the values from 45 to 134 (upper direction) are represented by the value of 1, the values from 135 to 224 (left direction) are represented by the value of 2, and the values from 225 to 314 (lower direction) are represented by the value of 3. The values of the magnitudes of the gradient vectors are ternarized (values: 0 to 2). The value of combination is calculated by using the following equations: Value of Combination = 0 ( if Magnitude of Gradient Vector = 0 ) , Value of Combination = ( Direction of Gradient Vector + 1 ) × Magnitude of Gradient Vector ( if Magnitude of Gradient Vector > 0 ) . Accordingly, the number of combinations becomes 94 Therefore, the number of sets of data of the second characteristic values C0 can be reduced. A histogram about the plurality of sample images, which are recognized as non-facial images, is also generated in a similar manner. For generating the histogram about the sample images, which are recognized as non-facial images, pixels (similar reference numerals P1-P4 are used) corresponding to the positions of the pixels P1-P4 in the sample images, which are recognized as facial images, are used. The logarithmic value of the ratio between the frequency values represented by the two histograms is calculated. The calculated values are represented in a histogram illustrated in the extreme right side of FIG. 9. This histogram is used as the discriminator. Each value on the vertical axis of this histogram, which is the discriminator, is hereinafter referred to as a discrimination point. According to this discriminator, if the distribution of the second characteristic value C2 corresponds to positive discrimination points, the possibility that the image is a facial image is high. If the absolute value of the discrimination point is larger, the possibility is higher. In contrast, if the distribution of the characteristic value C2 of an image corresponds to negative discrimination points, the possibility that the image is a non-facial image is high. If the absolute value of the discrimination point is larger, the possibility is higher. In step S2, a plurality of discriminators, in the form of histograms as described above, is generated for the combination of the characteristic value C2 at each pixel included in a plurality of kinds of pixel groups, which may be used for discrimination. Then, the most effective discriminator for discriminating whether the image is a facial image is selected from the plurality of discriminators, which were generated in step S2. Weight of each sample image is considered to select the most effective discriminator. In this example, a weighted correct answer rate of each discriminator is compared with each other, and a discriminator, of which weighted correct answer rate is the highest, is selected as the most effective discriminator (step S3). Specifically, in the first step S3, the weight of each sample image is equally 1. Therefore, a discriminator, which can correctly discriminate whether an image is a facial image regarding a largest number of sample images, is simply selected as the most effective discriminator. Meanwhile, in the second step S3 after the weight of each sample image is updated in step S5, which will be described later, there are sample images, of which weight is 1, sample images, of which weight is larger than 1, and sample images, of which weight is smaller than 1. Therefore, when the correct answer rate is evaluated, the sample image, of which weight is larger than 1, is counted more heavily than the sample image, of which weight is 1. Accordingly, in the second or later step S3, processing is focused on correctly discriminating a sample image, of which weight is large, than correctly discriminating a sample image, of which weight is small. Next, processing is performed to check whether the correct answer rate of the combination of the discriminators, which have been selected so far, exceeds a predetermined threshold value (step S4). The correct answer rate of the combination of the discriminators is the rate that the discrimination result as to whether each sample image is a facial image by using the combination of the discriminators, which have been selected so far, is the same as the actual answer as to whether the image is a facial image. Here, either the present sample image group after weighting or an equally weighted sample image group may be used to evaluate the correct answer rate of the combination. If the rate exceeds the predetermined threshold value, the probability of discriminating whether the image is a facial image by using the discriminators, which have been selected so far, is sufficiently high. Therefore, learning ends. If the rate is not higher than the predetermined threshold value, processing goes to step S6 to select an additional discriminator, which will be used in combination with the discriminators, which have been selected so far. In step S6, the discriminator, which was selected in the most recent step S3, is excluded so as to avoid selecting the same discriminator again. Next, if a sample image is not correctly discriminated as to whether the image is a facial image by using the discriminator, which was selected in the most recent step S3, the weight of the sample image is increased. If a sample image is correctly discriminated as to whether the image is a facial image, the weight of the sample image is reduced (step S5). The weight is increased or reduced as described above to improve the effects of the combination of the discriminators. When the next discriminator is selected, the selection is focused on the images, which could not be correctly discriminated by using the discriminators, which have been already selected. A discriminator, which can correctly discriminate the images as to whether they are facial images, is selected as the next discriminator. Then, processing goes back to step S3, and the next most effective discriminator is selected based on the weighted correct answer rate as described above. Processing in steps S3-S6 as described above is repeated. When a discriminator, which corresponds to the combination of the characteristic value C2 at each pixel forming a specific pixel group, is selected as an appropriate discriminator for discriminating whether an image includes a face, if the correct answer rate of the combination, which is checked in step S4, exceeds a threshold value, the type of the discriminator, which will be used for discriminating whether a face is included, and the discrimination condition are determined (step S7). Accordingly, learning of the second reference data R2 ends. Then, learning of the first reference data R1 is performed by obtaining the type of the discriminator and the discrimination condition in a similar manner to the method as described above. When the learning method as described above is adopted, the discriminator is not limited to the discriminator of the histogram type as described above. The discriminator may be in any form as far as it can provide criteria for discriminating a facial image from a non-facial image by using the combination of the first characteristic value C1 and the second characteristic value C2 at each pixel, which forms a specific pixel group. For example, the discriminator may be binary data, a threshold value, a function, or the like. Further, other kinds of histograms such as a histogram showing the difference value between the two histograms, which are illustrated at the center of FIG. 9, may also be used. Further, the learning method is not limited to the method as described above. Other machine learning methods such as a neural network method may also be used. The first reference data R1 and the second reference data R2 may be data empirically determined by a skilled technician. The CPU 12 refers to the discrimination conditions, which were learned by the first reference data R1 about all of the combinations of the first characteristic value C1 at each pixel, which forms a plurality of kinds of pixel groups. Then, the CPU 12 obtains a discrimination point for the combination of the first characteristic value C1 at each pixel, which forms each pixel group. The CPU 12 discriminates whether a face is included in the frame Fri by using all of the discrimination points. At this time, the direction of the gradient vector K, which is a first characteristic value C1, is quaternarized, for example, in the same manner as learning of the first reference data R1. In the present embodiment, all the discrimination points are added, and discrimination is carried out based on whether the sum is a positive value or a negative value. For example, if the sum of the discrimination points is a positive value, it is judged that the frame Fri includes a facial candidate. If the sum of the discrimination points is a negative value, it is judged that the frame Fri does not include a facial candidate. The processing, which is performed by the CPU 12, for discriminating whether the frame Fri includes a facial candidate is referred to as first discrimination. Here, unlike the sample image, which has the size of 30×30 pixels, the frame Fri has various sizes. Further, when a face is included in the frame Fri, the rotation angle of the face on a plane is not always 0 degree. Therefore, the CPU 12 enlarges or reduces the frame Fri in a stepwise manner so that the size of the frame Fri in the longitudinal direction or the lateral direction becomes 30 pixels, as illustrated in FIG. 10. At the same time, the CPU 12 rotates the frame Fri on the plane 360 degrees in a stepwise manner. (FIG. 10 illustrates the reduction state.) A mask M, which has the size of 30×30 pixels, is set on the enlarged or reduced frame Fri at each stage of deformation. Further, the mask M is moved pixel by pixel on the enlarged or reduced frame Fri, and processing is performed to discriminate whether the image in the mask M is a facial image. Accordingly, the CPU 12 discriminates whether the frame Fri includes a facial candidate. During generation of the first reference data R1 and the second reference data R2, the sample images, in which the distance between the centers of both eyes is 9 pixels, 10 pixels or 11 pixels, were used for learning. Therefore, the enlargement rate during enlargement or reduction of the frame Fri and the facial candidate may be 11/9. Further, the sample images, which were used for learning during generation of the first and second reference data R1 and R2, are images, in which a face is rotated on a plane within the range of +15 degrees. Therefore, the frame Fri and the facial candidate may be rotated in 30 degree increments in a stepwise manner over 360 degrees. The CPU 12 calculates the first characteristic value C1 and the second characteristic value C2 at each stage of deformation such as enlargement or reduction and rotation of the frame Fri and the facial candidate. Then, the CPU 12 discriminates whether a facial candidate is included in the frame Fri at each stage of enlargement or reduction and rotation of the frame Fri. If it is judged even once that a facial candidate is included in the frame Fri, the CPU 12 judges that a facial candidate is included in the frame Fri. The CPU 12 extracts a region of 30×30 pixels, which corresponds to the position of the mask M, at which it was discriminated that a facial candidate was included in the mask M, as a facial candidate, from the frame Fri, which has the size and rotation angle at the stage when it was discriminated that the facial candidate was included. Further, the CPU 12 deforms the extracted facial candidate in a same manner with the deformation as described above by enlarging or reducing the facial candidate in a stepwise manner. The CPU 12 refers to the discrimination conditions, which were learned by the second reference data R2 about all of the combinations of the characteristic value C2 at each pixel, which forms a plurality of kinds of pixel groups in the extracted facial candidate. The CPU 12 obtains a discrimination point about the combination of the characteristic value C2 at each pixel, which forms each pixel group, at each stage of deformation. Then, the CPU 12 discriminates whether the facial candidate is a face by using all of the discrimination points. At this time, the direction of the gradient vector K, which is the second characteristic value C2, is quarternarized, and the magnitude of the gradient vector K, which is the second characteristic value C2, is ternarized. In the present embodiment, it is assumed that all the discrimination points are added, and discrimination is performed by judging whether the addition value is positive or negative. For example, if the summation of the discrimination points is a positive value, it is judged that the facial candidate is a face. If the summation of the discrimination points is a negative value, it is judged that the facial candidate is not a face. The processing for discriminating whether the facial candidate is a face is referred to as second discrimination. If it is judged that a facial candidate is not included in the frame Fri in the first discrimination, or even if it is judged that a facial candidate is included in the frame Fri in the first distinction, if it is judged that the facial candidate is not a face in the second discrimination, the CPU 12 judges that a face is not included in the frame Fri. In this case, the CPU 12 performs the first and second discrimination on a frame Fri+1 after predetermined time (for example after 10 frames) to judge whether a face is included in the frame Fri+1 in a similar manner to the discrimination as described above. If the facial candidate, which was discriminated in the first discrimination, is discriminated as a face in the second discrimination, it is judged that a face is included in the frame Fri. When it is judged that the face is included in the frame Fri, the coordinate values at four corners of the region of 30×30 pixels, which corresponds to the position of the mask M, at which it was discriminated that the face was included, are obtained. Here, since the frame Fri was enlarged or reduced during discrimination of the face, the facial position is detected by obtaining four coordinate values in the frame Fri of an original size, corresponding to the coordinate values at four corners of the region of 30×30 pixels. The obtained facial position is stored in the system memory 34 as information Pi, which represents the facial position. Therefore, in the present embodiment, the information Pi, which represents the facial position, is the coordinate values at four corners of a rectangle enclosing the face included in the frame Fri. The information Pi, which represents the facial position, is not limited the coordinate values as described above. The center position, which is the coordinate of the intersection of the diagonal lines of the mask M, and the length of the radius of a circle with its center at the center position may also be used as the information Pi, which represents the facial position. After the CPU 12 stores the information Pi, which represents the facial position, in the system memory 34, the CPU 12 also calculates the variation of the image from the frame Fri to the frame Fri+1 after predetermined time (after 10 frames, for example). Specifically, the CPU 12 adds the pixel values of all the pixels in each of the frame Fri and the frame Fri+1, and divides the obtained addition values with the total number of pixels in each of the frame Fri and the frame Fri+1, respectively. Accordingly, the average values (hereinafter referred to as Mi and Mi+1) of the pixel values are calculated for the frame Fri and the frame Fri+1, respectively. Then, the absolute value |ΔM| of the difference between the average value Mi and the average value Mi+1 is calculated as the variation. Then, the CPU 12 judges whether the variation |ΔM| has exceeded a predetermined threshold value Th1. Here, if a scene has been switched between the two frames of the frame Fri and the frame Fri+1, the variation |ΔM| of the image between the two frames is relatively large. If a scene has not been switched, the variation |ΔM| of the image between the two frames is not so large. Therefore, a value, which is sufficient for discriminating whether the scene has been switched, may be used as the threshold value Th1. The threshold value Th1 may be empirically obtained by calculating the variation between two frames when the scene is actually switched. If the variation |ΔM| is less than or equal to the threshold value Th1, it is judged that the scene is not switched between the two frames of the frame Fri and the frame Fri+1. Then, the CPU 12 reads out the information Pi about the facial position, stored in the system memory 34. Regarding the frame Fri+1, the CPU 12 performs judgment processing, only on the facial position detected in the frame Fri and the vicinity of the facial position, to judge whether a face is included in the frame Fri+1. Specifically, as illustrated in FIG. 11, since the information Pi about the facial position is the coordinate values at four corners of the rectangle enclosing the face included in the frame Fri, judgment is made as to whether a face is included in a rectangular region Ai+1, which has the size of approximately 1.2 times of the size of the rectangular region Ai, with the rectangular region Ai at the center of the rectangular region Ai+1. In the processing for judging whether a face is included in the frame Ai+1, both of the first distinction and the second distinction may be performed. Alternatively, only the second distinction may be performed. Then, when the CPU 12 judges that a face is included in the frame Fri+1, the CPU 12 obtains information Pi+1, which represents the facial position, in a similar manner to the obtainment of the information about the frame Fri. The information Pi, which represents the facial position, is replaced by the information Pi+1, and the information Pi+1 is stored in the system memory 34. If the variation |ΔM| exceeds the threshold value Th1, it is judged that the scene is switched between the two frames of the frame Fri and the frame Fri+1. Then, the CPU 12 performs judgment processing, on the whole frame Fri+1, to judge whether a face is included in the frame Fri+1 in a similar manner to the judgment as described above. Further, when the variation |ΔM| is less than or equal to the threshold value Th1, if it is not judged that a face is included, it is judged that the scene is switched between the two frames of the frame Fri and the frame Fri+1. The CPU 12 performs judgment processing, on the whole frame Fri+1, to judge whether a face is included in a similar manner to the judgment as described above. The CPU 12 repeatedly performs the processing for judging whether a face is included, and if it is judged that the face is included, processing for recording the information Pi+1, representing the newly detected facial position, in the system memory 34 until the user drives the release button to perform the photographing operation. Then, when the user performs the photographing operation by pressing the release button, the CPU 12 performs red-eye correction processing on the image data, which is obtained when the photographing operation is performed. The red-eye correction processing may be performed by using the technique disclosed in Japanese Unexamined Patent Publication No. 10(1998)-233929. Specifically, a human face is detected in an image represented by image data, and pixels, which have the pixel value of red, are detected in the detected facial region. The pixel value of red is changed to the pixel value of black. In the present embodiment, the facial position may be specified based on the information Pi about the facial position, which is stored in the system memory 34 when the photographing operation is performed. Therefore, the processing for detecting the human face from the image represented by the image data is not required. Hence, processing for detecting the pixels, which have the pixel value of red, and if the red pixel is detected, processing for changing the color of the pixel to black may be performed only on the image in the rectangular region Ai, represented by the information Pi about the facial position. Next, processing performed in the present embodiment will be described. FIGS. 12 and 13 are flow charts illustrating the processing performed in the present embodiment. Processing starts when the user switches the mode of the digital camera 1 to a photography mode. First, the CPU 12 sets a first frame Fri (i=1) as a frame, on which processing for judging whether a face is included is performed (step S11). Then, the CPU 12 performs processing for judging whether a face is included in the frame Fri (step S12). FIG. 14 is a flow chart illustrating processing for judging whether a face is included. First, the CPU 12 calculates the direction of the gradient vector K in the frame Fri at each stage of enlargement or reduction and rotation of the frame Fri as the first characteristic value C1 (step S31). Then, the CPU 12 reads out the first reference data R1 from the system memory 34 (step S32), and performs first discrimination for discriminating whether a facial candidate is included in the frame Fri (step S33). If step S33 is YES, the CPU 12 extracts the facial candidate from the frame Fri (step S34). Here, the CPU 12 may extract a plurality of facial candidates. Next, the CPU 12 calculates the second characteristic value C2 in the facial candidate at each stage of enlargement or reduction and rotation of the facial candidate (step S35). Then, the CPU 12 normalizes the second characteristic value C2 (step S36). The CPU 12 reads out the second reference data R2 from the system memory 34 (step 37), and performs the second discrimination for discriminating whether the facial candidate is a face (step S38). If step S38 is YES, the CPU 12 judges that the frame Fri includes a face (step S39), and processing ends. If steps S33 and S38 are NO, the CPU 12 judges that the frame Fri does not include a face (step S40), and processing ends. If it is judged that a face is not included, the CPU 12 changes the processing object to the next frame, which is a frame after predetermined time (i=i+1, step S13), and processing goes back to step S12. If it is judged that a face is included, the facial position is detected (step S14), and the information Pi, which represents the facial position, is stored in the system memory 34 (step S15). Then, the CPU 12 judges whether the user has performed the photographing operation by pressing the release button (step S16). If step S16 is NO, the CPU 12 changes the processing object to the next frame, which is a frame after predetermined time (step S17), and calculates the variation |ΔM| of the image between the frame Fri+1 and the frame Fri (step S18). The CPU 12 judges whether the variation |ΔM| exceeds the threshold value Th1 (step S19). If step S19 is YES, CPU 12 judges that the scene is switched between the two frames of the frame Fri and the frame Fri+1. Then, the processing returns to step S12 so that the processing for judging whether a face is included is performed on the whole frame Fri+1 in a similar manner to the processing as described above. If step S19 is NO, the CPU 12 judges that the scene is not switched between the two frames of the frame Fri and the frame Fri+1, and reads out the information Pi about the facial position, stored in the system memory 34 (step S20). Regarding the frame Fri+1, the CPU 12 performs judgment processing only on the facial position, detected in the frame Fri, and the vicinity of the facial position, to judge whether a face is included in the frame Fri+1 (step S21). If it is judged that a face is not included, processing goes back to step S13. If it is judged that a face is included, the processing goes back to step S14, and the facial position is detected. In step S15, the information Pi, which represents the facial position, is stored in the system memory 34. If step S16 is YES, red-eye correction processing is performed on the image data, which is obtained when the photographing operation is performed (step S22). Then, the image data after red-eye correction processing is displayed on the LCD (Liquid Crystal Display) 40 (step S23). Further, the image data is recorded on the memory card 30 (step S24), and photography processing ends. Here, when a photograph is taken with the digital camera 1, after composition is determined, a few seconds are required before the release means is driven. In many cases, the subject does not move during the few seconds. Therefore, judgment is made, in a predetermined time interval, as to whether a face is included in the frame, and if it is judged that the face is included, the facial position is newly detected and stored in the system memory 34. Accordingly, the facial position, which is stored in the system memory 34, corresponds to the position of a face included in the image represented by image data, which is obtained by the photographing operation. Hence, when red-eye correction processing is performed on the image data obtained by photographing, if the information Pi about the facial position is used, detection of the face in the image, which is represented by the image data, is not required. Accordingly, time required for the red-eye correction processing can be reduced in the present embodiment. Further, wait time till displaying the image data, obtained by photographing, on the LCD 40 or time till enabling the user to take a photograph of the next image can be reduced. Consequently, a photographer can be relieved from stress, which he/she will feel if the wait time is long. Further, processing may be performed to judge whether the variation |ΔM| of the image between the two frames of the frame Fri and the frame Fri+1 exceeds the threshold value Th1, and if the variation |ΔM| is less than or equal to the threshold value Th1, the processing for judging whether a face is included may be performed only on the facial position recorded in the system memory 34 and the region in the vicinity of the facial position in the frame Fri+1. Accordingly, if the scene is not switched between the two frames of the frame Fri and the frame Fri+1, it is not required to perform the processing, on the whole frame Fri+1, to judge whether a face is included. Therefore, processing time for judging whether a face is included may be reduced. In the embodiments as described above, the average values of the pixel values in each of the frame Fri and the frame Fri+1 are used for obtaining the variation |ΔM| of image between the frame Fri and the frame Fri+1. Alternatively, as illustrated in FIGS. 15A and 15B, histograms Hi and Hi+1, which show the relationships between the pixel values and the frequencies in each of the frame Fri and the frame Fri+1, may be obtained, and the difference (namely, the area of the shaded part in FIG. 15C) in the shapes of the histograms Hi and Hi+1 may be used as the variation. In this case, processing for judging whether the scene has been switched may be performed by judging whether the variation exceeds a predetermined threshold value (referred to as Th2). Further, in the embodiments as described above, the red-eye correction processing is performed on the image data, which is obtained by performing a photographing operation. However, a human face may be detected in an image, and processing for improving the image quality of the face, such as suppressing the noise and changing the density or gradation of the detected face, may be performed on the image data. In this case, if the information Pi, which represents the facial position, and which is stored in the system memory 34, is used, processing for detecting the face is not required. Therefore, the processing time may be reduced. In the embodiments as described above, only a set of image data is obtained by performing the photographing operation. However, a plurality of frames which are temporally precedent and subsequent frames of the image data, obtained by performing the photographing operation, may be obtained as a set of image data. For example, as illustrated in FIG. 16, when the photography mode is set, 30 frames are sequentially obtained per second. A plurality of frames (7 frames in this case), which are temporally precedent and/or subsequent frames of the frame (hereinafter referred to a standard frame Frs), which is obtained when the photographing operation is performed, may be obtained as a set of image data. Further, it is obvious that, only a plurality of temporally precedent frames or a plurality of temporally subsequent frames may be obtained as a set of image data. As described above, for obtaining a plurality of frames as image data, judgment may be made as to whether eyes in a face included in the standard frame Frs are closed. If the eyes are closed, a frame including a face with open eyes may be selected from the plurality of frames. Further, judgment may be made as to whether a face included in the standard frame Frs is a smiling face, and if the face is not a smiling face, a frame including a smiling face may be selected from the plurality of frames. Here, for judging whether the eyes are closed or whether the face is a smiling face, a face is required to be detected in an image. In the present embodiment, since the information Pi about the facial position, stored in the system memory 34, is used, processing for detecting the face is not required. Accordingly, processing time for judging whether the eyes are closed or whether the face is a smiling face may be reduced. Further, in the present embodiment, the processing for judging whether a face is included in the frame Fri is performed by using the reference data R1 and R2, which has been obtained by using a machine learning method. However, it is obvious that other methods, such as a method for judging whether a shape, which conforms to a facial template, is included in the frame Fri by using the facial template, may also be used. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a photographing apparatus, such as a digital camera, for obtaining image data by taking a photograph and storing the obtained image data in a storage means such as a memory card. The present invention also relates to a photographing method for the photographing apparatus and a program for causing a computer to execute the photographing method. 2. Description of the Related Art Conventionally, when a photograph of a person is taken using a strobe (an electronic flash), there is a problem that the person's eyes glow red or gold in the photograph. This is a so-called red-eye phenomenon. The red-eye phenomenon occurs when strobe light passes through the pupils of the eyes, is reflected at the retinas of the eyes, and the reflected light is captured in a film. Various systems for automatically detecting and correcting the red-eye as described above have been proposed. Particularly, various photographing apparatuses such as digital cameras have been proposed, which correct the red-eye in image data obtained with the digital cameras, by performing correction processing in the digital cameras, (for example, Japanese Unexamined Patent Publication No. 10(1998)-233929, Japanese Unexamined Patent Publication No. 11(1999)-127371, and Japanese Unexamined Patent Publication No. 2000-305141). However, red-eye correction processing requires detection of a human face in an image, represented by the image data, first, and further detection of the positions of the eyes in the detected face. The red-eye correction processing also requires correction processing for changing the color of the eyes from red to black. Since the digital cameras have much lower processing capacity than personal computers, a long time is required for the red-eye correction processing. Hence, there is a problem that the wait time becomes long until performing a next operation, such as displaying an obtained image on a liquid crystal monitor of a digital camera after photographing, or getting the digital camera ready to take a next photograph. | <SOH> SUMMARY OF THE INVENTION <EOH>In view of the foregoing circumstances, it is an object of the present invention to reduce time for performing image processing on image data when predetermined image processing, such as red-eye correction processing, is performed on the image data in photographing apparatuses such as digital cameras. A photographing apparatus according to the present invention is a photographing apparatus comprising: a photographing means for obtaining image data by taking a photograph of a subject; a display means for displaying various kinds of information including the image data; a release means for performing photographing operation; a storage means for storing various kinds of information including the image data; a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means; a face judgment means for performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; a face detection means for detecting a facial position in a frame, which is judged to include a face, if the face judgment means judges that the face is included in the frame; and a control means for controlling the photographing means, the face judgment means, the face detection means, and the storage means so that the detected facial position is stored in the storage means, judgment is made as to whether the face is included in the next frame after the predetermined time, and if the judgment is positive, the facial position is detected, the facial position, which is stored in the storage means, is replaced by the newly detected facial position and the newly detected facial position is stored in the storage means, and until the release means performs the photographing operation, judgment is made as to whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, the facial position is detected, and the newly detected facial position is stored in the storage means, and a frame obtained when the release means performs the photographing operation and/or a plurality of temporally precedent and/or subsequent frames of the obtained frame are stored in the storage means as the image data. When the photograph is taken with the photographing apparatus such as the digital camera, the moving image of the subject is displayed on the display means until photographing operation is performed by using the release means. The moving image includes 15 to 30 frames per second. Therefore, the “predetermined time” may be set in advance by determining the number of frames included in the predetermined time. For example, the predetermined time may be a time between two temporally adjacent frames, or a time including 5 or 10 frames. The photographing apparatus according to the present invention may further include a variation judgment means for referring to the frame, which was judged to include the face, and its next frame, thereby judging whether the variation in an image between the two frames exceeds a predetermined value, and the control means may be a means for controlling the face judgment means so that if the variation judgment means judges that the variation is less than or equal to the predetermined value, the face judgment means performs processing, only on the region including the facial position stored in the storage means and the vicinity of the facial position, to judge whether the face is included in the next frame, and if the variation judgment means judges that the variation exceeds the predetermined value, the face judgment means performs processing on the whole region of the next frame, to judge whether the face is included in the next frame. The clause “variation in an image between the two frames” refers to the variation, by which whether a scene has been switched between the two frames can be judged. Specifically, the absolute value of the difference in the average value of the pixel values between the two frames, the difference in the shapes of the histograms, or the like may be used as the variation. Here, if a scene is switched between the two frames, the variation in the image between the two frames is relatively large. If a scene is not switched between the two frames, the variation in the image between the two frames is not so large. Therefore, a value, based on which whether the scene has been switched can be discriminated, may be used as the “predetermined value”. The “predetermined value” may be obtained experimentally by calculating the variation between two frames when the scene is actually switched between the two frames. The photographing apparatus according to the present invention may further include an image processing means for performing predetermined image processing, related to a face, on the image data by referring to the facial position, stored in the storage means, after the photographing operation is performed. The “predetermined image processing related to a face” may be any kind of processing as long as the processing is performed on a face, which has been detected in an image represented by image data. For example, the “predetermined image processing related a face” may be processing for improving the image quality of the face, such as at least one of red-eye correction processing, noise suppression processing on the face, density correction processing, and gradation correction processing. Alternatively, the “predetermined image processing related a face” may be processing for judging whether the eyes are closed in the detected face, and if the eyes are closed, selecting a frame including the face with open eyes from temporally preceding and/or subsequent frames of the frame, which was obtained when the photographing operation was performed. The “predetermined image processing related a face” may also be processing for judging whether the detected face is a smiling face, and if it is not a smiling face, selecting a frame including a smiling face from temporally preceding and/or subsequent frames of the frame, which was obtained when the photographing operation was performed. A photographing method according to the present invention is a photographing method for a photographing apparatus including a photographing means for obtaining image data by taking a photograph of a subject, a display means for displaying various kinds of information including the image data, a release means for performing photographing operation, a storage means for storing various kinds of information including the image data, and a photographing control means for obtaining a moving image of the subject by continuously taking photographs with the photographing means and displaying the moving image on the display means, the method comprising the steps of: performing processing, in a predetermined time interval, for judging whether a human face is included in a frame included in the moving image until a positive result is obtained in the judgment; detecting a facial position in a frame, which is judged to include a face, if it is judged that the face is included in the frame; and storing the detected facial position in the storage means, judging whether the face is included in the next frame after the predetermined time, and if the judgment is positive, detecting the facial position, replacing the facial position, which is stored in the storage means, by the newly detected facial position and storing the newly detected facial position in the storage means, and until the release means performs the photographing operation, judging whether the face is included in the next frame further after the predetermined time, and if it is judged that the face is included in the frame, detecting the facial position, and storing the newly detected facial position in the storage means, and storing a frame, which is obtained when the release means performs the photographing operation, and a plurality of temporally precedent and/or subsequent frames of the obtained frame in the storage means as the image data. The photographing method according to the present invention may be provided as a program for causing a computer to execute the photographing method. According to the present invention, the moving image of the subject, which is obtained with the photographing apparatus, is displayed on the display means during photographing. Then, judgment is made, in a predetermined time interval, as to whether a human face is included in the frames forming the moving image until a positive result is obtained in the judgment. If it is judged that a face is included in a frame, the facial position is detected in the frame, which is judged to include the face, and the detected facial position is stored in the storage means. Next, judgment is made as to whether a face is included in a temporally subsequent frame after the predetermined time. If the judgment is YES, the facial position is detected. The facial position, which is stored in the storage means, is replaced by the newly detected facial position, and the newly detected facial position is stored in the storage means. Then, until the release means performs photographing operation, judgment is made as to whether a face is included in the next frame after a predetermined time, and if it is judged that the face is included, the facial position is detected and the newly detected facial position is stored in the storage means. When the release means performs the photographing operation, the frame obtained by photographing and/or a plurality of temporally preceding and/or subsequent frames of the obtained frame are stored in the storage means as image data. Here, when a photograph is taken, after the composition is determined, a few seconds are required before the release means is driven. In many cases, the subject does not move during the few seconds. Therefore, judgment is made, in a predetermined time interval, as to whether a face is included in the frame, and if it is judged that the face is included, the facial position is newly detected and stored in the storage means. Accordingly, the facial position, which is stored in the storage means, corresponds to the facial position included in the image represented by image data, which is obtained by the photographing operation. Hence, when predetermined image processing related to a face is performed on the image data obtained by photographing, face detection processing in the image, represented by the image data, is not required. Accordingly, time required for the image processing can be reduced. Further, the wait time until displaying the image data obtained by photographing on the display means, or time until getting the photographing apparatus ready to take a photograph of the next image can be reduced. Consequently, a photographer can be relieved from stress, which he/she will feel if the wait time is long. Further, the frame, which is judged to include a face, and its next frame are referred to, and judgment is made as to whether the variation in the image between the two frames exceeds a predetermined value. If the variation is less than or equal to the predetermined value, judgment is made as to whether a face is included in the next frame by performing processing only on the region of the next frame, including the facial position stored in the storage means and the vicinity of the facial position. Accordingly, if the scene is not switched between the two frames, it is not required to perform the judgment processing on the whole region of the next frame as to whether the face is included. Therefore, processing time for judging whether a face is included can be reduced. Note that the program of the present invention may be provided being recorded on a computer readable medium. Those who are skilled in the art would know that computer readable media are not limited to any specific type of device, and include, but are not limited to: floppy disks, CD's RAM'S, ROM's, hard disks, magnetic tapes, and internet downloads, in which computer instructions can be stored and/or transmitted. Transmission of the computer instructions through a network or through wireless transmission means is also within the scope of this invention. Additionally, computer instructions include, but are not limited to: source, object and executable code, and can be in any language including higher level languages, assembly language, and machine language. | 20050119 | 20080205 | 20050915 | 59002.0 | 2 | LE, BRIAN Q | PHOTOGRAPHING APPARATUS, METHOD AND PROGRAM | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,093 | ACCEPTED | Sample repairing apparatus, a sample repairing method and a device manufacturing method using the same method | An object of the present invention is to provide a sample repairing apparatus, a sample repairing method and a device manufacturing method using the same method, which can reduce an edge roughness in a repaired pattern and also can provide the repairing of a sample by applying an electron beam-assisted etching or an electron beam-assisted deposition. There is provided a sample repairing method comprising: (a) a step of focussing an electron beam by an objective lens to irradiate a sample: (b) a step of supplying a reactive gas onto an electron beam irradiated surface of said sample: (c) a step of selectively scanning a pattern to be repaired on said sample with the electron beam so as to repair said pattern by applying an etching or a deposition; and (d) a step of providing a continuous exhausting operation by means of a differential exhaust system arranged in said objective lens so as to prevent the reactive gas supplied onto said electron beam irradiated surface from flowing toward an electron gun side. | 1. A sample repairing method, comprising: (a) irradiating a sample with an electron beam focussed by an objective lens; (b) supplying a reactive gas onto a surface of said sample irradiated with the electron beam; (c) selectively scanning a pattern to be repaired on said sample with the electron beam so as to repair said pattern by etching or applying deposition; and (d) providing a continuous exhaust operation by means of a differential exhaust system arranged in said objective lens so as to prevent the reactive gas supplied onto said surface irradiated with the electron beam from flowing toward an electron gun side. 2. A sample repairing method in accordance with claim 1, in which said sample is applied with a negative voltage. 3. A sample repairing method in accordance with claim 1, in which a landing energy of said electron beam is equal to or less than 3 keV. 4. A sample repairing method in accordance with claim 1, in which said focussed electron beam Is a shaped beam that has been shaped Into a rectangle having parallel sides in the x-direction and in the y-direction, or a shaped beam that has been shaped into a rectangle having sides inclined at predetermined angles relative to the x-direction and the y-direction. 5. A sample repairing method, comprising the steps of: (a) irradiating a sample with an electron beam emitted from an electron gun through an objective lens; (b) obtaining an image of said sample surface; (c) searching for a region to be repaired on said sample from said image of said sample surface and scanning said region to be repaired by the electron beam; (d) increasing a pressure of a reactive gas in said region on said sample subject to the scanning with the electron beam; and (e) confirming the completion of said repairing of said sample, wherein a small aperture for limiting the pressure is disposed between said sample and said objective lens. 6. A sample repairing method in accordance with claim 5, in which said electron gun has a ZrO/W Schottky cathode or a TaC cathode, and an electron beam emitted in a direction away from an optical axis is used. 7. A sample repairing method in accordance with claim 5, in which said objective lens for focussing said electron beam to be finer comprises: a magnetic lens having a magnetic gap formed in the sample side thereof; and an axially symmetric electrode disposed in the sample side of said magnetic lens and having a potential higher than that of the sample. 8. A sample repairing method in accordance with claim 5, in which a beam separator is provided in the electron gun side of said objective lens or inside said objective lens, and said step of obtaining the image of said sample surface Includes a step of deflecting secondary electrons emitted from said sample, by said beam separator and detecting said secondary electrons by a detector to thereby obtain the image of said sample surface. 9. A device manufacturing method comprising: preparing wafers; preparing a mask or reticle; repairing said mask or reticle using a repairing method defined in claim 1; carrying out a lithography for said wafers by using said repaired mask or wafer; and assembling devices using said processed wafers. 10. A sample repairing apparatus for repairing a sample, comprising: an electron gun for emitting an electron beam; an objective lens for focussing the electron beam to irradiate a sample; a gas supply for supplying a reactive gas onto a surface of said sample irradiated with the electron beam; and a differential exhaust system disposed in said objective lens and operative to keep exhausting the reactive gas so as to inhibit the reactive gas supplied onto said surface irradiated with the electron beam by said gas supply from flowing toward an electron gun side, wherein a pattern to be repaired on said sample is selectively scanned with the electron beam so as to repair said pattern by etching or applying deposition. 11. A sample repairing apparatus in accordance with claim 10, in which said sample is applied with a negative voltage. 12. A sample repairing apparatus in accordance with claim 10, in which a landing energy of said electron beam is equal to or less than 3 keV. 13. A sample repairing apparatus in accordance with claim 10, further comprising a condenser lens located downstream to the electron gun and a shaping aperture plate located upstream or downstream to said condenser lens, in which said shaping aperture plate comprises: a first shaping aperture for shaping said electron beam that has been focussed by said condenser lens into a rectangle having parallel sides in the x-direction and in the y-direction: and a second shaping aperture for shaping said electron beam that has been focussed by said condenser lens into a rectangle having sides inclined at predetermined angles relative to the x-direction and the y-direction, wherein said first shaping aperture and said second shaping aperture are switchable from each other. 14. A sample repairing apparatus for repairing a sample, comprising: an electron gun for emitting an electron beam; an objective lens for focussing said electron beam emitted from said electron gun to irradiate a sample: an image obtaining means for obtaining an image of said sample surface; a gas supply for supplying a reactive gas onto an electron beam irradiated surface of said sample so as to increase a pressure of the reactive gas in the electron beam scanning region on the sample; and a small aperture disposed between said sample and said objective lens for limiting the pressure of said reactive gas, wherein a region to be repaired of said sample is searched for based on said image of said sample surface, which has been obtained by said image obtaining means, and also an orientation of the pattern to be repaired is measured, and then said region to be repaired is scanned with the electron beam in parallel with a side of said pattern to repair it by etching or applying deposition. 15. A sample repairing apparatus in accordance with claim 14, in which said electron gun has a ZrO/W Schottky cathode or a TaC cathode, and an electron beam emitted in a direction away from an optical axis is used. 16. A sample repairing apparatus in accordance with claim 14, in which said objective lens for focussing said electron beam to be finer comprises; a magnetic lens having a magnetic gap formed in a sample side thereof; and an axially symmetric electrode disposed in the sample side of said magnetic lens and having a potential higher than that of the sample. 17. A sample repairing apparatus in accordance with claim 14, in which a beam separator is provided in the electron gun side of said objective lens or inside said objective lens, and said image obtaining means for obtaining the image of said sample surface obtains the image of the sample surface through the steps of deflecting secondary electrons emitted from said sample, by said beam separator and detecting said secondary electrons by a detector. 18. A sample repairing method, comprising; (a) supplying a reactive gas onto a surface of a sample; (b) selectively scanning a pattern to be repaired on said sample with an electron beam focussed by an objective lens so as to repair said pattern by etching or applying deposition; and (c) providing a continuous exhaust operation by means of a differential exhaust system arranged in said objective lens so as to prevent the reactive gas supplied onto said surface from flowing toward an electron gun side. | BACKGROUND OF THE INVENTION The present invention relates to a sample repairing apparatus and a sample repairing method for repairing a defect with high accuracy in a sample, such as a mask, used in the production of a device or the like having a line width equal to or less than 0.1 μm, and further to a device manufacturing method using such a sample repairing method. There has been a known method in the prior art, in which a sample, such as a mask, is irradiated with a finely focussed electron beam and then a reactive gas is blown to the irradiated region thereof with a nozzle so as to carry out the etching of the sample. When the mask subject to the repairing has the minimum line width as narrow as about 90 nm, the edge roughness in the repaired pattern should be controlled to be of the order of some ten nm or less, which in turn requires to focus the beam to be half a size of the required roughness or smaller than that. On the other hand, from the reason that the electron beam, if having a higher landing energy, could cause a back scattering after an incidence upon the sample and the reflected beam thereof could emit secondary electrons to contribute to the etching, there is another problem that a precision of processing would be not greater than that limited by the extent of the back scattered electrons. Besides, it has been a main stream to use an ion beam for repairing the mask in the prior art. The repairing apparatus employing the focussed ion beam has a problem that an ion implantation to a mask substrate or a damage from an irradiation beam could deteriorate a transmittance in a silica substrate, substantially inhibiting the repair of opaque defect from being carried out, which is considered to be a serious problem especially in the F2 lithography. REFERENCE [Non-Patent Document] A set of advance copies from the NEXT GENERATION LITHOGRAPHY WORKSHOP (NGL2003), Jul. 10 and 11, 2003, National Museum of Emerging Science and Innovation, “Next generation Electron Beam mask repair tool”, Dr. Jayant Neogi, Johannes Bihr and Klaus Edinger, hosted by: Silicon Technology Subcommittee, Next Generation Lithography Technology Workshop, Japan Society of Applied Physics, co-hosted by: No. 132 committee, “Industrial Application of Charged Particle Beam”, Japan Society of the Promotion of Science. SUMMERY OF THE INVENTION The present invention has been made in the light of the above-pointed problems pertaining to the prior art, and an object thereof is to provide a sample repairing apparatus, a sample repairing method and a device manufacturing method using the same method, which can reduce an edge roughness in a repaired pattern and also can repair a sample by applying an electron beam-assisted etching or an electron beam-assisted deposition. The present invention provides a sample repairing method, comprising: (a) a step of focussing an electron beam by an objective lens to irradiate a sample; (b) a step of supplying a reactive gas onto an electron beam irradiated surface of said sample; (c) a step of selectively scanning a pattern to be repaired on said sample with the electron beam so as to repair said pattern by applying an etching or a deposition; and (d) a step of providing a continuous exhausting operation by means of a differential exhaust system arranged in said objective lens so as to prevent the reactive gas supplied onto said electron beam irradiated surface from flowing toward an electron gun side. Further, it is more preferred that said sample may be applied with a negative voltage. Further, preferably a landing energy of the electron beam may be equal to or less than 3 keV. Further, said focussed electron beam may define a shaped beam that has been shaped into a rectangle having parallel sides in the x-direction and in the y-direction, or a shaped beam that has been shaped into a rectangle having sides inclined at predetermined angles (e.g., 45 degrees) relative to the x-direction and the y-direction. The present invention provides another sample repairing method, comprising: (a) a step of transmitting an electron beam emitted from an electron gun through an objective lens to irradiate a sample; (b) a step of obtaining an image of said sample surface; (c) a step of searching for a region to be repaired on said sample from said image of said sample surface and scanning said region to be repaired by the electron beam: (d) a step of increasing a pressure of a reactive gas in said region on said sample subject to the scanning with the electron beam; and (e) a step of confirming the completion of said repairing of said sample, wherein a small aperture for limiting the pressure is disposed between said sample and said objective lens. Further, more preferably said electron gun has a Zro/W Schottky cathode or a TaC cathode, and an electron beam emitted in the direction having a certain angle with respect to an optical axis is used. Further, It is more preferred that said objective lens for focussing said electron beam to be finer comprises a magnetic lens having a magnetic gap formed in the sample side thereof and an axially symmetric electrode disposed in the sample side of said magnetic lens and having a potential higher than that of the sample. Yet further, an E×B separator may be provided in the electron gun side of said objective lens or inside said objective lens, and said step of obtaining the image of said sample surface may include a step of deflecting secondary electrons emitted from said sample, by said B×B separator and detecting said secondary electrons by a detector to thereby obtain the image of said sample surface. Further, the present invention provides a device manufacturing method for carrying out a lithography by using a mask which has been repaired in accordance with the sample repairing method defined in any one of claim 1 through 8. The present invention provides a sample repairing apparatus for repairing a sample, comprising: an objective lens for focussing an electron beam to Irradiate a sample; a gas supply for supplying a reactive gas onto an electron beam irradiated surface of said sample: and a differential exhaust system disposed in said objective lens and operative to keep exhausting the reactive gas so as to inhibit the reactive gas supplied onto said electron beam irradiated surface by said gas supply from flowing toward an electron gun side, wherein a pattern to be repaired on said sample is selectively scanned with an electron beam so as to repair said pattern by applying an etching or a deposition. Further, it is more preferred that said sample may be applied with a negative voltage. Further, preferably a landing energy of said electron beam may be equal to or less than 3 keV. In addition, the apparatus may further comprise a condenser lens located downstream to the electron gun and a shaping aperture plate located upstream or downstream to said condenser lens, in which said shaping aperture plate comprises: a first shaping aperture for shaping said electron beam that has been focussed by said condenser lens into a rectangle having parallel sides in the x-direction and in the y-direction; and a second shaping aperture for shaping said electron beam that has been focussed by said condenser lens into a rectangle having sides inclined at predetermined angles (e.g., 45 degrees) relative to the x-direction and the y-direction, wherein said first shaping aperture and said second shaping aperture are switchable from each other. The present invention provides another sample repairing apparatus for repairing a sample, comprising: an electron gun for emitting an electron beam; an objective lens for focussing said electron beam emitted from said electron gun to irradiate a sample; an image obtaining means for obtaining an Image of said sample surface: a gas supply for supplying a reactive gas onto an electron beam irradiated surface of said sample so as to increase a pressure of the reactive gas in the electron beam scanning region on said sample: and a small aperture disposed between said sample and said objective lens for limiting the pressure of said reactive gas, wherein a region to be repaired of said sample is searched for from said image of said sample surface, which has been obtained by said image obtaining means, and then said region to be repaired is scanned with the electron beam to repair it by applying an etching or a deposition. Further, preferably said electron gun has a ZrO/W Schottky cathode or a TaC cathode, and an electron beam emitted in the direction having a certain angle relative to the optical axis is used. Further, it is more preferred that said objective lens for focussing said electron beam to be finer comprises: a magnetic lens having a magnetic gap formed in a sample side thereof; and an axially symmetric electrode disposed in the sample side of said magnetic lens and having a potential higher than that of the sample. Furthermore, an E×B separator may be provided in the electron gun side of said objective lens or inside said objective lens, and said image obtaining means for obtaining the image of said sample surface obtains the image of the sample surface through the steps of deflecting secondary electrons emitted from said sample, by said E×B separator and detecting said secondary electrons by a detector. According to the invention as defined In claim 1 or claim 10, the edge roughness in the repaired pattern can be reduced. Further, owing to the objective lens with a structure for the differential exhaust system, an amount of a reactive gas flowing into the electron gun side is reduced, thus reducing the number of cleaning operations of the optical column. According to the invention as defined in claim 5 or claim 14, the repairing of the sample, such as a mask, can be carried out successfully by applying an electron beam-assisted etching or an electron beam-assisted deposition. Further, since the beam can be focussed to be finer even during use (introduction) of the reactive gas, a fine-controlled repairing can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of an exemplary electron beam apparatus (i.e., an electron beam optical column) to be used in a sample repairing method according to the present invention: FIG. 2 provides schematic diagrams, specifically illustrating how a mask is repaired in a sample repairing method according to the present invention; FIG. 3 is a schematic diagram illustrating another exemplary electron beam apparatus (i.e. an electron beam optical column) to be used in a sample repairing method according to the present invention: FIG. 4 shows an exemplary arrangement of apertures in a shaping aperture plate, which may be used in the above electron beam apparatus according to the present invention; FIG. 5 is a flow chart illustrating, by way of example, a semiconductor device manufacturing method; and FIG. 6 is a flow chart illustrating a lithography process in the semiconductor device manufacturing method of FIG. 5. Components in the attached drawings are designated as follows: 1 Zr—W tip 2 Schottky shield 3 Tip heating W filament 4 Condenser lens 5 Shaping aperture plate 6 Rectangular aperture 7 Rectangular aperture 8 NA aperture 9 Reduction lens 10 Objective lens system 11 High vacuum exhaust pipe 12 Low vacuum exhaust pipe 13 Gas Injection tube 14 Low vacuum exhaust pipe 15 Negative power supply 16 Mask 17 Cooling gas 18 B×B separator 19 Secondary electron detector (SE detector) 20 Deflector 21 Cr pattern 22 Opaque defect 23 Shaped beam 23′ Shaped beam 26 Clear defect 31 Cathode 32 Wehnelt or Schottky shield 33 Anode 34 Condenser lens 35 Shaping aperture plate 36 Reduction lens 37 Electrostatic deflector 38 E×B separating and scanning electrostatic deflector 39 E×B separating deflector (electromagnetic deflector) 40 Objective lens 41 O ring 42 Magnetic gap 43 Small aperture 44 Axially symmetric electrode 45 Pressure wall 46 Pressure bulkhead 47 Mask 48 Guard ring 49 Exhaust pipe 50 Gas introducing tube 51 Locus 52 Secondary electron locus 53 Secondary electron detector (SE detector) 54 Pivot deflection 56 Aperture DETAILED DESCRIPTION OF THE INVENTION A best mode for carrying out a sample repairing apparatus, a sample repairing method and a device manufacturing method using the same method according to the present invention will now be described with reference to the attached drawings. FIG. 1 shows schematically an electron beam apparatus (i.e., an electron beam optical column) used in a repairing method of a sample, such as a mask and the like, according to the present invention. As illustrated, an electron gun comprises a Zr—W tip 1, a Schottky shield 2 and a tip heating W filament 3, taking advantage of Schottky emission. An electron beam emitted from this electron gun is focussed with a condenser lens 4 to form a crossover image in an NA aperture 8. A shaping aperture plate 5 serving as a shaping aperture Is disposed in a sample (mask) side of a condenser lens 4. The shaping aperture plate 5 includes a rectangular aperture (a first shaping aperture) having sides extending in parallel in the x-direction and the y-direction and another rectangular aperture (a second shaping aperture) 7 having sides angled at a predetermined angle of 45 degrees relative to the x-direction and the y-direction, each formed through the plate 5, in which the rectangular aperture 6 and the rectangular aperture 7 are adapted to be switched from each other by sliding and thereby moving the shaping aperture plate 5 or by deflecting the irradiating beam. Thus, the electron beam that has passed through the rectangular aperture 6 of the shaping aperture plate 5 forms a rectangular-shaped beam having its sides extending in parallel in the x-direction and the y-direction, while on the other hand, the electron beam that has passed through the rectangular aperture 7 having its sides angled at 45 degrees relative to the x-direction and the y-direction forms a rectangular-shaped beam having its sides angled at 45 degrees relative to the x-direction and the y-direction. It is to be noted that the illustrated embodiment represents a case of the electron beam passing through the rectangular aperture 6. Although the rectangular aperture 7 is shown to be angled at 45 degrees relative to the x-direction and the y-direction, the sides are not necessarily angled at 45 degrees but it may have the sides angled at certain degrees proximal to the angles in conformity with patterned sides, for example, 30 or 60 degrees. The electron beam, once having passed through the rectangular aperture 6 or the rectangular aperture 7 to be shaped into a rectangular shape, is then reduced with a reduction lens 9 and an objective lens system 10 into an image on a mask 16 (A step of focussing the electron beam by the objective lens to irradiate the sample). The objective lens system 10 defines an uni-potential lens system having three electrodes designed to have a particularly small bore and a particularly large lens gap. Onto a back surface of the sample or the mask 16 has been blown a cooling gas 17 to prevent a temperature rise. Further, the mask 16 is applied with a negative voltage by a negative power supply 15. Since the cathode of the electron gun has a voltage of 4500V and the mask 16 is being applied with a voltage of −4000V, the sample is resultantly irradiated with 500 eV of energy. With 500 eV of energy, the extent of back scattered electrons in Cr of a light absorbing material of the mask 16 is limited to 50 nm or shorter, which allows a sufficiently precise processing of the mask to be carried out. The voltage of the cathode of the electron gun (acceleration voltage for the electron beam) is in a range of 0.5 to 10 kV, and the potential of the wafer could be variable in a range of 0 to −5 kV. An etching gas represented by halogen gases, such as chlorine or fluorine gases, is injected onto an electron beam Irradiated surface of the sample from a gas injection tube 13 serving as a gas supply (A step of supplying the reactive gas onto the electron beam irradiated surface of the sample). The gas used herein is not limited, but any types of gas may be used so far as it can provide etching process with the aid of the EB irradiation, including hydrogen and oxygen. A low vacuum exhaust pipe 12 is coupled to a vacuum pump (not shown) for low vacuum operation, which serves as an exhaust system, while on the other hand, a high vacuum exhaust pipe 11 is coupled to a turbo-molecular pump (not shown), so that a differential exhaust system can prevent the reactive gas filling up over the electron beam irradiated surface from flowing toward the electron gun side (A step of providing a continuous exhausting operation by means of a differential exhaust system arranged in the objective lens so as to prevent the reactive gas supplied onto the electron beam irradiated surface from flowing toward the electron gun side). The objective lens system 10, that has been designed to have the particularly small bore diameter and the particularly large lens gap as mentioned above, can provide for an effective differential exhausting operation. The low vacuum exhaust pipe 14 is also coupled to the exhaust system. Besides, in order to prevent the primary beam from being blurred and the beam current contained in the beam having fine beam diameter from being reduced, a pressure of the gas over the sample surface is controlled to be a certain pressure level which is just sufficient to meet a pressure requirement for the etching. It is to be noted that the differential exhaust system is provided in the objective lens system in the illustrated embodiment, but it may be provided at any locations in the vicinity of the sample so far as the reactive gas supplied onto the sample surface can be exhausted effectively. A deflector 20 and an E×B separator 18 allow scanning with the electron beam in any desired directions on the sample surface for providing the etching, and occasional SEM scanning can be applied to detect an end point of the etching (A step of selectively scanning the pattern to be repaired on the sample with the electron beam so as to repair the pattern by applying an etching or a deposition). At this time, the secondary electrons emanated from the sample surface pass through the objective lens system 10, deflected (toward the left in FIG. 1) by the E×B separator 18 and finally detected by a secondary electron detector 19 (SE detector). In this way, a SEM image can be obtained, and thus obtained SEM image can be monitored to see whether or not the Cr has been left in a region of the opaque defect. Further, upon detecting the end point of the etching, the gas supply from the gas injection tube 13 can be suspended immediately to thereby reduce the gas pressure in a short time to the pressure level for preventing the further etching process. Furthermore, the voltage applied to each of the electrodes of the objective lens system 10 is limited to a value of voltage that would not induce an electric discharge. Further, from the fact that the break down voltage depends on a surface condition of the electrode, the respective electrodes of the objective lens 10 have been coated with gold or platinum. FIG. 2 shows, by way of example, how to repair an opaque defect and a clear defect. FIG. 2(A) shows a case of an opaque defect 22 adhering to a Cr pattern 21 extending along the x-direction. In this case, the scanning operation is performed with such a shaped beam 23 having a size about one half of a minimum line width, which has been shaped through the rectangular aperture 6 of the shaping aperture plate 5 into a rectangle having the sides extending in parallel in the x-direction and the y-direction, to be driven In the x-direction (the direction designated by reference numeral 24 in FIG. 2(A)) so as to apply the etching to peel away (repair) the opaque defect 22. FIG. 2(B) shows a case containing an opaque defect 22 adhering to a pattern 21 extending along the y-direction. In this case also, the scanning operation is performed with such a shaped beam 23 having a size about one half of a minimum line width, which has been shaped through the rectangular aperture 6 of the shaping aperture plate 5 into a rectangle having the sides extending in parallel in the x-direction and the y-direction, to be driven in the y-direction (the direction designated by reference numeral 24′ in FIG. 2(B)) so as to apply the etching to peel away (repair) the opaque defect 22. FIG. 2(C) shows a case containing an opaque defect 22 adhering to a pattern 21 extending along the directions angled at 45 degrees relative to the x-direction and the y-direction. In this case, the scanning operation is performed with such a shaped beam 23′, which has been shaped through the rectangular aperture 7 of the shaping aperture plate 5 into a rectangle having the sides angled at 45 degrees relative to the x-direction and the y-direction, to be driven in the directions angled at 45 degrees relative to the x-direction and the y-direction (the directions designated by reference numeral 25 in FIG. 2(C)) so as to apply the etching to peel away (repair) the opaque defect 22. FIG. 2(D) shows, by way of example, a case for repairing a clear defect 26 in a pattern 21 extending along the x-direction, and in this case, the etching gas of halogens may be replaced with a gas capable of providing a deposition of tungsten metal. This gas may be such a gas that contains a metal and Is decomposed by the electron beam to form a deposition of metal, including carbonyls and methyls of metal, and the metal may be tungsten, copper, noble metals such as silver, aluminum or chrome. In case of FIG. 2(D), the scanning operation is performed with such a shaped beam 23, which has been shaped through the rectangular aperture 6 of the shaping aperture plate 5 into a rectangle having the parallel sides in the x-direction and the y-direction, to be driven in the x-direction (the direction designated by reference numeral 24 in FIG. 2(D)) so as to repair a clear defect 26. FIG. 2(E) shows a case for repairing a clear defect 26 in a pattern extending along the y-direction. In this case also, the scanning operation is performed with such a shaped beam 23, which has been shaped through the rectangular aperture 6 of the shaping aperture plate 5 into a rectangle having the sides extending in parallel in the x-direction and the y-direotion, to be driven in the y-direction (the direction designated by reference numeral 24′ in FIG. 2(E)) so as to repair the clear defect 26. FIG. 2(F) shows a case for repairing a clear defect 26 in a pattern 21 extending along the directions angled at 45 degrees relative to the x-direction and the y-direction. In this case, the scanning operation is performed with such a beam 23′, which has been shaped through the rectangular aperture 7 of the shaping aperture plate 5 into a rectangle having the sides angled at 45 degrees relative to the x-direction and the y-direction, to be driven in the direction angled at 45 degrees relative to the x-direction and the y-direction (the direction designated by reference numeral 25 in FIG. 2(F)) so as to repair the clear defect 26. Another embodiment of a sample repairing method according to the present invention will now be described. FIG. 3 shows schematically an electron beam apparatus (electron beam optical column) used in the repairing method for repairing defects in a mask, in which an electron beam that has been focussed to be finer by an objective lens is irradiated onto the mask so as to repair the defect therein. A cathode 31 has employed a Schottky cathode of Zr/O-W or a thermal field emission cathode of TaC. Reference numeral 32 designates a Wehnelt or Schottky shield, and reference numeral 33 designates an anode. An electron gun comprises the cathode 31, the Wehnelt or Schottky shield 32 and the anode 33, and is configured for emitting electron beams from the Zr—W Schottky cathode or the TaC cathode 31 to the directions away from the optical axis, for example, in four directions away from the optical axis, in which those electron beams emitted from the electron gun are focussed by the condenser lens 34. This condenser lens 34 is made of electromagnetic lens which is capable of not only focussing the electron beams but also adjusting a rotational displacement of each electron beam in the azimuthal direction. A shaping aperture plate 35 is disposed in the sample (mask) side of the condenser lens 34. An aperture 56 is formed In the shaping aperture plate 35. As shown in FIG. 4, at least one aperture 56 is formed in the shaping aperture plate 35 in a location offset from the optical axis so as to permit one of four beam 55 that have been emitted from the electron gun in four different directions away from the optical axis to pass through the aperture 56. Accordingly, an ion beam along the optical axis, which otherwise Is to flow toward the electron gun, can be blocked. The beam passes through either one of the apertures 56 in the shaping aperture plate 35 and is reduced by means of a reduction lens 36 and an objective lens (an electromagnetic lens for an objective lens) 40, and thereby the beam is irradiated onto the mask 47 (sample to be repaired) as a beam of small-diameter in the order of about 50 nm. That is, the electron beam that has been focussed to be finer by the objective lens 40 is irradiated onto the mask 47 (A step of focussing the electron beam emitted from the electron gun to be finer by means of at least the objective lens to irradiate the sample). Using a two-stage deflector system including an electrostatic deflector 37 and an E×B separating and scanning electrostatic deflector 38 disposed on the objective lens 40 defined in the electron gun side, the mask 47 is scanned in the two-dimensional manner to allow the secondary electrons emanating from the mask 47 surface (sample) to pass through a small aperture 43, then to be deflected toward the direction of the secondary electron locus 52 by the E×B separating and scanning electrostatic deflector 38 and the E×B separating deflector (electromagnetic deflector) 39 and finally to be detected by the secondary electron detector (SE detector) 53. Through those steps, a SEM image can be obtained (A step of obtaining the SEM image of the sample) and the obtained SEM image can be monitored to search for a region to be repaired. If the region to be repaired is located, the scanning is applied only to that region (A step of searching for the region to be repaired on the sample from the SEM image of the sample and scanning the region to be repaired by the electron beam) and an reactive gas is introduced from a gas introduction tube 50 serving as a gas supply (A step of increasing a pressure of the reactive gas in the region on the sample subject to the scanning with the electron beam) to apply an etching (electron beam-assisted etching) or a deposition (electron beam-assisted deposition) thereto. Further, after the repairing operation has been completed, the SEM image is obtained again and the checking operation Is performed over the SEM image to see whether or not the repairing has been accurately completed (A step of confirming the completion of the repairing of the sample). Since a small aperture (an aperture for NA and for limiting a pressure) 43 is disposed between the mask 47 and the objective lens and so the region defined in the electron gun side is kept in high vacuum with the aid of the small aperture 43, even when the gas is introduced, therefore the beam would not be blurred but can be focussed to be finer, thereby providing a precise repairing. Further, since a distance between the small aperture 43 and the mask 47 is short, a magnitude of blur of the beam, if any, could be limited to an extremely minute magnitude. The objective lens 40 for focussing said electron beam to be finer comprises a magnetic lens (electromagnetic lens) 40 including a magnetic gap 42 formed therein defined in the mask 47 side and an axially symmetric electrode 44 disposed in the mask 47 side with respect to the magnetic lens 40 and having a potential higher than that of the mask 47. Since the negative voltage in the order of −4000V is applied to the mask 47 and the positive high voltage is applied to the electrode 44, therefore even with the landing energy not higher than 1 keV, it will be still possible to focus the beam to be sufficiently finer. Further, since a locus 51 during the scanning defines a pivot point 54 of deflection in the electron gun side with respect to the small aperture 43, an aberration during the deflection can be reduced. A pressure wall 45 and a pressure bulkhead 46 define a partition wall for separating an exhaust pipe 49 coupled to a vacuum pump (not shown) and a gas introduction tube 50 from each other and are made of insulating material. A guard ring 48 is disposed below the pressure bulkhead 46 to reduce a space with respect to the pressure bulkhead 46, which also helps prevent a large amount of gas from flowing into a region defined in a sample chamber side. Further, an O-ring 41 is provided to separate a coil of the magnetic lens 40 from the vacuum environment. Since the system uses only one of four beams emitted from the Zr/O-W Schottky cathode of the electron gun in four different directions angled with respect to the optical axis is used, the beam of high intensity can be used, which means that even with the beam that has been focussed to 50 nm, a beam current equal to or more than 500 nA can be still obtained. Accordingly, the repairing operation can be carried out with high throughput, and also the observation of the SEM image can be carried out with good S/N ratio even with the beam focussed for detecting the end-point. Since it is not known that in which direction of the azimuthal angles θ of the beams emitted from the Zr—W Schottky cathode of the electron gun in four directions away from the optical axis the stronger beam 55 is shot, a plurality of apertures 56 (two in the illustrated embodiment) of the shaping aperture plate 35 can be disposed in the direction of the azimuthal angles θ of the beam, which are spaced from each other by a distance corresponding to a diameter of the beam on the shaping aperture plate 35, as shown in FIG. 4. With this arrangement, a rotational amount to be adjusted by the condenser lens (magnetic lens) 34 can be reduced, It is to be noted that although the Illustrated embodiment shows an example using an inspection apparatus of the SEM type (scanning electron microscope), the present invention is not limited thereto but is applicable to the inspection apparatus of projecting optical system using the principle of parallel image-taking and to the inspection apparatus by ion beam using ions (referred to as a charged particle beam including an electron beam) or by light beam using light. It is to be noted that although the description has been directed to the repairing operation applied to the mask in the above-Illustrated embodiments, the present invention is not limited to this but is applicable to a wafer in the course of fabrication of an advanced device (GaAs wafer in the course of fabrication of a discrete device). By using the mask repaired by the above-described sample repairing method, a well-performed lithography can be carried out in the device manufacturing method. With reference to FIGS. 5 and 6, the description will now be directed to an embodiment for carrying out a method for manufacturing a semiconductor device by using a mask repaired by the above-described sample repairing method. FIG. 5 is a flow chart showing an embodiment of a manufacturing method of a semiconductor device according to the present invention. The manufacturing process in this embodiment includes the following main processes. (1) A wafer manufacturing process for manufacturing a wafer (or wafer preparing process for preparing a wafer). (Step 100) (2) A mask manufacturing process for fabricating a mask to be used in the exposure (or a mask preparing process for preparing a mask). (Step 101) (3) A wafer processing process for performing any processing treatments necessary for the wafer. (Step 102) (4) A chip assembling process for cutting out those chips formed on the wafer one by one to make them operative. (Step 103) (5) A chip inspection process for inspecting an assembled chip. (Step 104) It is to be appreciated that each of those main processes further comprises several sub-processes. Among those main processes, one that gives a critical affection to the performance of the semiconductor device is (3) the wafer processing process. In this wafer processing process, the designed circuit patterns are deposited on the wafer one on another, thus to form many chips, which will function as memories or MPUs. This wafer processing process includes the following sub-processes. (A) A thin film deposition process for forming a dielectric thin film to be used as an insulation layer, a metallic thin film to be formed into a wiring section or an electrode section, and the like (by using the CVD process or the sputtering). (B) An oxidizing process for oxidizing the wafer substrate, which is another means to form those thin films. (C) A lithography process for forming a resist pattern by using a mask (reticle) in order to selectively process the thin film layers and/or the wafer substrate. (D) An etching process for processing the thin film layer and/or the wafer substrate in conformity to the resist pattern (by using, for example, the dry etching technology). (E) An ions/impurities implant and diffusion process. (F) A resist stripping process. (G) An inspection process for inspecting the processed wafer. It is to be noted that the wafer processing process must be performed repeatedly as desired depending on the number of layers contained in the wafer, thus to manufacture the device that will be able to operate as designed. A flow chart of FIG. 6 shows the lithography process included as a core process in said wafer processing process. The lithography process comprises the respective processes as described below. (a) A resist coating process for coating the wafer having a circuit pattern formed thereon in the preceding stage with the resist. (Step 200) (b). An exposing process for exposing the resist. (Step 201) (c) A developing process for developing the exposed resist to obtain the pattern of the resist. (Step 202) (d) An annealing process for stabilizing the developed pattern. (Step 203) All of the semiconductor device manufacturing process, the wafer processing process, and the lithography process described above are well-known, and so any further description on them should not be necessary. When a defect inspection method and a defect inspection apparatus according to the present invention is used in the above-described inspection process of (G), any defects can be detected with high throughput even on a semiconductor device having a fine pattern, enabling the 100-percent inspection and thus the improvement in yield of the products as well as the avoidance of shipping of any defective products to be achieved. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to a sample repairing apparatus and a sample repairing method for repairing a defect with high accuracy in a sample, such as a mask, used in the production of a device or the like having a line width equal to or less than 0.1 μm, and further to a device manufacturing method using such a sample repairing method. There has been a known method in the prior art, in which a sample, such as a mask, is irradiated with a finely focussed electron beam and then a reactive gas is blown to the irradiated region thereof with a nozzle so as to carry out the etching of the sample. When the mask subject to the repairing has the minimum line width as narrow as about 90 nm, the edge roughness in the repaired pattern should be controlled to be of the order of some ten nm or less, which in turn requires to focus the beam to be half a size of the required roughness or smaller than that. On the other hand, from the reason that the electron beam, if having a higher landing energy, could cause a back scattering after an incidence upon the sample and the reflected beam thereof could emit secondary electrons to contribute to the etching, there is another problem that a precision of processing would be not greater than that limited by the extent of the back scattered electrons. Besides, it has been a main stream to use an ion beam for repairing the mask in the prior art. The repairing apparatus employing the focussed ion beam has a problem that an ion implantation to a mask substrate or a damage from an irradiation beam could deteriorate a transmittance in a silica substrate, substantially inhibiting the repair of opaque defect from being carried out, which is considered to be a serious problem especially in the F 2 lithography. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>FIG. 1 is a schematic diagram of an exemplary electron beam apparatus (i.e., an electron beam optical column) to be used in a sample repairing method according to the present invention: FIG. 2 provides schematic diagrams, specifically illustrating how a mask is repaired in a sample repairing method according to the present invention; FIG. 3 is a schematic diagram illustrating another exemplary electron beam apparatus (i.e. an electron beam optical column) to be used in a sample repairing method according to the present invention: FIG. 4 shows an exemplary arrangement of apertures in a shaping aperture plate, which may be used in the above electron beam apparatus according to the present invention; FIG. 5 is a flow chart illustrating, by way of example, a semiconductor device manufacturing method; and FIG. 6 is a flow chart illustrating a lithography process in the semiconductor device manufacturing method of FIG. 5 . detailed-description description="Detailed Description" end="lead"? Components in the attached drawings are designated as follows: 1 Zr—W tip 2 Schottky shield 3 Tip heating W filament 4 Condenser lens 5 Shaping aperture plate 6 Rectangular aperture 7 Rectangular aperture 8 NA aperture 9 Reduction lens 10 Objective lens system 11 High vacuum exhaust pipe 12 Low vacuum exhaust pipe 13 Gas Injection tube 14 Low vacuum exhaust pipe 15 Negative power supply 16 Mask 17 Cooling gas 18 B×B separator 19 Secondary electron detector (SE detector) 20 Deflector 21 Cr pattern 22 Opaque defect 23 Shaped beam 23 ′ Shaped beam 26 Clear defect 31 Cathode 32 Wehnelt or Schottky shield 33 Anode 34 Condenser lens 35 Shaping aperture plate 36 Reduction lens 37 Electrostatic deflector 38 E×B separating and scanning electrostatic deflector 39 E×B separating deflector (electromagnetic deflector) 40 Objective lens 41 O ring 42 Magnetic gap 43 Small aperture 44 Axially symmetric electrode 45 Pressure wall 46 Pressure bulkhead 47 Mask 48 Guard ring 49 Exhaust pipe 50 Gas introducing tube 51 Locus 52 Secondary electron locus 53 Secondary electron detector (SE detector) 54 Pivot deflection 56 Aperture | 20050119 | 20070814 | 20050929 | 68745.0 | 0 | WELLS, NIKITA | SAMPLE REPAIRING APPARATUS, A SAMPLE REPAIRING METHOD AND A DEVICE MANUFACTURING METHOD USING THE SAME METHOD | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,194 | ACCEPTED | Lock release operator layout structure in vehicle | In a vehicle including a plurality of containing portions, namely, a front containing portion provided in an inner cover covering from the rear side a head pipe of a vehicle body frame at its front end and constituting a part of a vehicle body cover which can be locked in a fully closed condition, to facilitate the operation for releasing the lock conditions of the plurality of containing portions. A plurality of lock release operating buttons for respectively releasing the locked conditions of a plurality of containing portions inclusive of a front containing portion is disposed at an inner cover on a lateral side of the front containing portion. | 1. A lock release operator layout structure in a vehicle comprising: containing portions including a front containing portion provided in an inner cover for covering from a rear side a head pipe of a vehicle body frame at a front end and constituting a part of a vehicle body cover; a lock for selectively locking said containing portions in a fully closed condition; and lock release operators for releasing the locked condition of said containing portions, said lock release operators being disposed at said inner cover on a lateral side of said front containing portion. 2. The lock release operator layout structure in a vehicle as set forth in claim 1, wherein said lock release operators are disposed at positions set off to either the left or right side from the vehicle body center line. 3. The lock release operator layout structure in a vehicle as set forth in claim 1, wherein a plurality of said lock release operators formed to be horizontally elongated are arranged in a vertically aligned pattern. 4. The lock release operator layout structure in a vehicle as set forth in claim 2, wherein a plurality of said lock release operators formed to be horizontally elongated are arranged in a vertically aligned pattern. 5. The lock release operator layout structure in a vehicle as set forth in claim 1, wherein the lock release operator for releasing the lock condition of said front containing portion, a case lock mechanism of said front containing portion, and an electric actuator for exerting an unlocking force on said case lock mechanism are disposed at substantially the same height. 6. The lock release operator layout structure in a vehicle as set forth in claim 2, wherein the lock release operator for releasing the lock condition of said front containing portion, a case lock mechanism of said front containing portion, and an electric actuator for exerting an unlocking force on said case lock mechanism are disposed at substantially the same height. 7. The lock release operator layout structure in a vehicle as set forth in claim 3, wherein the lock release operator for releasing the lock condition of said front containing portion, a case lock mechanism of said front containing portion, and an electric actuator for exerting an unlocking force on said case lock mechanism are disposed at substantially the same height. 8. The lock release operator layout structure in a vehicle as set forth in claim 1, wherein a plurality of said lock release operators are arranged in a vertically aligned pattern. 9. The lock release operator layout structure in a vehicle as set forth in claim 2, wherein a plurality of said lock release operators are arranged in a vertically aligned pattern. 10. The lock release operator layout structure in a vehicle as set forth in claim 1, and further including a case lock mechanism having a pin-like striker attached to a lower surface of a case main body and a catcher turnably supported on the inner cover for catching the striker in accordance with a sliding of a containing case towards a closed position. 11. The lock release operator layout structure in a vehicle as set forth in claim 10, and further including an engaging member for engaging the catcher for holding the catcher in a state of catching the striker and a coil spring for biasing the engaging member in a direction for engagement with the catcher. 12. A containing structure for a vehicle, comprising: an inner cover for covering a rear side a head pipe of a vehicle body frame at a front end and for constituting a part of a vehicle body cover; and a containing case mounted to said inner cover in an openable and closable condition; wherein a holding mechanism for temporarily holding said containing case at an intermediate position between a fully closed position and a fully opened position of said containing case when said containing case is opened from said fully closed position is provided between said containing case and said inner cover so that its hold condition can be released. 13. The containing structure for a vehicle as set forth in claim 12, wherein said holding mechanism is capable of temporarily holding said containing case at a roughly central position between said fully closed position and said fully opened position. 14. The containing structure for a vehicle as set forth in claim 12, wherein said containing case is mounted to said inner cover so as to be slidable in the vehicle front-rear direction between said fully closed position where said containing case is contained in said inner cover and said fully opened position where said containing case projects from said inner cover, and a hold release operating member for releasing said hold condition of said holding mechanism is disposed at a lower surface of said containing case at a position near a vehicle body center line side and a vehicle body rear side. 15. The containing structure for a vehicle as set forth in claim 13, wherein said containing case is mounted to said inner cover so as to be slidable in the vehicle front-rear direction between said fully closed position where said containing case is contained in said inner cover and said fully opened position where said containing case projects from said inner cover, and a hold release operating member for releasing said hold condition of said holding mechanism is disposed at a lower surface of said containing case at a position near a vehicle body center line side and a vehicle body rear side. 16. The containing structure for a vehicle as set forth in claim 14, wherein a case lock mechanism for locking said containing case in said fully closed position according to the sliding of said containing case toward the closing side to said fully closed position and for releasing the lock condition according to the action of an unlocking force is provided between a support frame fixed to said inner cover and said containing case, and spring means for spring biasing said containing case in said fully closed position toward the opening side. 17. The containing structure for a vehicle as set forth in claim 15, wherein a case lock mechanism for locking said containing case in said fully closed position according to the sliding of said containing case toward the closing side to said fully closed position and for releasing the lock condition according to the action of an unlocking force is provided between a support frame fixed to said inner cover and said containing case, and spring means for spring biasing said containing case in said fully closed position toward the opening side. | BACKGROUND OF THE INVENTION CROSS-REFERENCE TO RELATED APPLICATIONS The present application is related to Japanese Patent Application Nos. 2004-012504 and 2004-012503 both filed on Jan. 20, 2004 the entire contents of which are hereby incorporated by reference. 1. Field of the Invention The present invention relates to a vehicle including a plurality of containing portions which include a front containing portion provided in an inner cover covering from the rear side a head pipe with a vehicle body frame at its front end and including a part of a vehicle body cover which can be locked in a fully closed condition. More particularly to a layout structure for a plurality of lock release operators for respectively releasing the lock conditions of the plurality of containing portions. The present invention also relates to a containing structure for a vehicle, including an inner cover for covering from the rear side a head pipe of a vehicle body frame at its front end and which constitutes a part of a vehicle body cover, and a containing case mounted to the inner cover in an openable and closable condition. 2. Description of Background Art A motor scooter type motorcycle wherein an inner cover includes a part of a vehicle body cover for covering a head pipe from the rear side that is provided with a containing portion is known, for example, in Japanese Patent Laid-open No. 2003-285692. In addition to the containing portion provided in the above-mentioned inner cover, a motorcycle generally includes other containing portion(s) such as, for example, a containing portion provided on the lower side of a rider's seat, and, in the conventional motorcycles, operating portions for releasing the lock conditions of the plurality of containing portions that are individually disposed respectively in the vicinity of the relevant containing portions. However, there are some cases where it is desired to release the lock conditions of the plurality of containing portions. In such cases, since the operating portions for releasing the lock conditions are apart from each other in the conventional motorcycle, the unlocking, lock releasing, operation is intricate to carry out. A structure wherein a containing case with its rear end along the vehicle body front-rear direction that can be opened is mounted to an inner cover constituting a part of a vehicle body cover for covering a head pipe from the rear side and in which a cover member is capable of closing a rear end opening portion of the containing case and mounted to the inner cover so as to be turnable between a full closure position and a full opening position is disclosed in Japanese Patent Laid-open No. 2001-260968. SUMMARY AND OBJECTS OF THE INVENTION The present invention has been made in consideration of the above circumstances. It is an object of the invention to provide a lock release operator layout structure in a vehicle by which an operation for releasing the lock conditions of a plurality of containing portions is facilitated. In order to attain the above object, the present invention sets forth a lock release operator layout structure in a vehicle including containing portions which include a front containing portion provided in an inner cover covering from the rear side a head pipe of a vehicle body frame at its front end and constituting a part of a vehicle body cover and which can be locked in a fully closed condition wherein the lock release operators for releasing the lock conditions of the containing portions are disposed at the inner cover on a lateral side of the front containing portion. The lock release operators correspond to lock release operating buttons 248a, 249a in an embodiment of the present invention which will be described later. In addition, the present invention provides the lock release operators that are disposed at positions set off to either the left or right side from the vehicle body center line. The present invention includes a plurality of the lock release operators formed to be horizontally elongate that are arranged in a vertically aligned pattern. Further, the present invention provides the lock release operator for releasing the lock condition of the front containing portion, a case lock mechanism possessed by the front containing portion, and an electric actuator for exerting an unlocking force on the case lock mechanism that are disposed at substantially the same height. The present invention includes a plurality of the lock releasing operators that are arranged in a vertically aligned pattern. According to the present invention, since the plurality of lock release operators for respectively releasing the lock conditions of the plurality of containing portions inclusive of the front containing portion are concentratedly disposed on a lateral side of the front containing portion, the operation for releasing the lock conditions of the plurality of containing portions is facilitated. According to the present invention, the unlocking, lock releasing, operation by the rider on the rider's seat is further facilitated. According to the present invention, the plurality of lock release operators can be disposed in a compact form so that the space in the vertical direction occupied by the lock release operators will not be large. According to the present invention, the wiring between the lock release operator for releasing the lock condition of the front containing portion as well as the power transmission system between the electric actuator and the case lock mechanism can be configured in a compact form. According to the present invention, the plurality of lock release operators can be so arranged that the space in the horizontal direction occupied by the lock release operations is narrowed. In addition, the above-mentioned structure according to the related art has a problem in that the cover member can be located only in either one of the fully closed position and the full opened position. Therefore, the containing case cannot be used in correspondence with various use conditions. The present invention has been made in consideration of the foregoing circumstances. It is an object of the present invention to provide a containing structure for a vehicle which makes it possible for a containing case to be used in correspondence with various use conditions. In order attain the above object, the present invention resides in a containing structure for a vehicle, including an inner cover for covering from the rear side a head pipe of a vehicle body frame at its front end and which constitutes a part of a vehicle body cover. A containing case is mounted to the inner cover in an openable and closable condition. A holding mechanism for temporarily holding the containing case at an intermediate position between a fully closed position and a fully opened position of the containing case when the containing case is opened from the fully closed position is provided between the containing case and the inner cover so that its hold condition can be released. The present invention provides a holding mechanism that is capable of temporarily holding the containing case at a roughly central position between the fully closed position and the fully opened position. The present invention provides a containing case that is mounted to the inner cover so as to be slidable in the vehicle front-rear direction between the fully closed position where the containing case is contained in the inner cover and the fully opened position where the containing case projects from the inner cover. A hold release operating member for releasing the hold condition of the holding mechanism is disposed at a lower surface of the containing case at a position near the vehicle body center line side and the vehicle body rear side. The present invention includes a case lock mechanism for locking the containing case in the fully closed position according to the sliding of the containing case towards the closing side to the fully closed position and for releasing the lock condition according to the action of an unlocking force is provided between a support frame fixed to the inner cover and the containing case, and spring means for spring biasing the containing case in the fully closed position toward the opening side is provided. According to the present invention, it is possible for momentarily holding the containing case at an intermediate position between the fully closed position and the fully opened position. Therefore, the containing cases can be used in correspondence with various use conditions. According to the present invention, things appropriate in size can be put into and taken out of the containing case while holding the containing case in the state of being opened to an appropriate degree. According to the present invention, the hold release operating member can be arranged at such a position wherein it can be easily operated at the time of releasing the condition where the containing case is temporarily held by the holding mechanism. Furthermore, according to the present invention, when an unlocking force is exerted to put the case lock mechanism into an unlocking operation, the containing case is slid from the fully closed position towards the opening side by the spring biasing force of the spring means, so that a part of the containing case projects from the inner cover. Therefore, it can easily be confirmed visually by the rider that the case lock mechanism has been put into the unlock condition. Moreover, the containing case can be drawn out with a small operating force. Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: FIG. 1 is a left side view of a motor scooter type motorcycle; FIG. 2 is a perspective view of a vehicle body frame in the condition where a fuel tank and a radiator are mounted; FIG. 3 is a left side view of an intermediate portion in the front-rear direction of the motor scooter type motorcycle in the condition where a rider's seat and a vehicle body cover are removed; FIG. 4 is a view along arrow 4 of FIG. 3 in the condition where a luggage box is removed; FIG. 5 is an enlarged vertically sectional side view of a rear portion of the motor scooter type motorcycle; FIG. 6 is a vertical sectional view of the surroundings of a rear portion of the luggage box; FIG. 7 is an enlarged view of an essential part of FIG. 5 in the condition where a front seat is opened; FIG. 8 is a view along arrow 8 of FIG. 7; FIG. 9 is an enlarged view along arrow 9 of FIG. 1; FIG. 10 is a general sectional view along line 10-10 of FIG. 9; FIG. 11 is a sectional view along line 11-11 of FIG. 9; FIG. 12 is a sectional view along line 12-12 of FIG. 11; FIG. 13 is a side view along arrow 13 of FIG. 10 of a containing case in a fully closed position; FIG. 14 is a view along arrow 14 of FIG. 13; FIG. 15 is a view of a case lock mechanism in the condition where the containing case is in the fully closed lock condition, as viewed in the same direction as FIG. 14; FIG. 16 is a view corresponding to FIG. 15, of the case lock mechanism in an unlocked condition; FIG. 17 is a side view corresponding to FIG. 13 in the condition where the containing case is temporarily held at a roughly central portion between the fully closed position and a fully opened position by a holding mechanism; FIG. 18 is a vertically sectional side view for showing the configuration of the holding mechanism; FIG. 19 is a sectional view along line 19-19 of FIG. 9; FIG. 20 is a sectional view along line 20-20 of FIG. 9; FIG. 21 is a diagram showing the configuration of a smart entry system; FIG. 22 is a sectional view along line 22-22 of FIG. 9; and FIG. 23 is an enlarged view of an essential part of FIG. 22. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Now, a mode for carrying out the present invention will be described below, based on one embodiment of the present invention shown in the accompanying drawings. As illustrated in FIG. 1, a vehicle body frame F of a motor scooter type vehicle includes, at the front end thereof, a front fork 25 for rotatably supporting a front wheel WF, and a head pipe 27 for steerably supporting a steering handle 26 connected to the front fork 25. A unit swing engine UE for supporting a rear wheel WR at the rear end thereof is vertically swingably supported on an intermediate portion in the front-rear direction of the vehicle body frame F. On the front side relative to the unit swing engine UE, a fuel tank 28 is a functional component part formed to be vertically elongated in a side view with a radiator 29 disposed on the rear side relative to the fuel tank 28 and mounted on the vehicle body frame F. In addition, a rider's seat 31, configured in a tandem form having a front seat 32 and a rear seat 33, is disposed at a rear portion of the vehicle body frame F. Further, a synthetic resin-made vehicle body cover 34 for covering the vehicle body frame F, a front portion of the unit swing engine UE, the fuel tank 28 and the radiator 29 is mounted on the vehicle body frame F. Referring to FIGS. 2 and 3, the vehicle body frame F includes the head pipe 27; a left-right pair of upper down frames 37 . . . connected to the head pipe 27 and extending rearwardly and downwardly with a left-right pair of lower down frames 38, 38 of which horizontal portions 38b . . . are integrally connected to the rear ends of inclined portions 38a . . . connected to the head pipe 27 on the lower side relative to the upper down frames 37 . . . and extending rearwardly and downwardly and of which the rear ends are welded to rear end portions of the upper down frames 37 . . . . A left-right pair of seat rails 39, 39 extend rearwardly and upwardly from intermediate portions of both the upper down frames 37 . . . with a left-right pair of rear frames 40, 40 for connection between rear portions of the upper down frames 37 . . . and rear portions of the seat rails 39 . . . ; and a left-right pair of support frames 41, 41 disposed on the outer sides of the lower down frames 38 . . . and the rear frames 40 . . . and extending in the front-rear direction. Both the support frames 41 . . . support, from the lower side, step floors 159 . . . possessed by the vehicle body cover 34 at left and right positions, the front ends of both the support frames 41 . . . are connected to lower portions of the inclined portions 38a . . . of the lower down frames 38 . . . , and the rear ends of both the support frames 41 . . . are connected to intermediate portions of the rear frames 40 . . . . Referring to FIGS. 4 and 5 also, the unit swing engine UE is composed of a water-cooled type engine E having a cylinder axis set substantially horizontal, and a belt-type continuously variable transmission M for transmitting the output of the engine E to the rear wheel WR through non-stage (stepless) speed change by a transmission belt and pulleys. The continuously variable transmission M is so configured so as to steplessly vary the speed change ratio by driving a movable pulley on the crankshaft side according to the operation of a speed change electric motor 42. A transmission case 43 of the continuously variable transmission M is provided in connection with the left side of a crankcase 44 of the engine E so as to bulge from the engine E to the left side, and extends to the left side of the rear wheel WR. In addition, a front end portion of a swing arm (not shown) is connected to the right side of the crankcase 44, and the rear wheel WR is rotatably supported between a rear end portion of the transmission case 43 and a rear end portion of the swing arm. Brackets 49, 49 are provided between intermediate portions of the seat rails 39 . . . and the rear frames 40 . . . in the vehicle body frame F, and a pair of support projecting portions 44a, 44a are provided on the upper surface of the crankcase 44 of the engine E. A link 50 includes a link tube portion 50a extending in the vehicle body width direction, and hollow cylindrical support tube portions 50b, 50b provided coaxially and integrally at both ends of the link tube portion 50a with both the support projecting portions 44a, 44a and the link tube portion 50a being connected by a connecting shaft 51. In addition, the support tube portions 50b, 50b at both ends of the link 50 are turnably supported on the bracket 49, 49 through support shafts 52, 52 parallel to the connecting shaft 51. In other words, the unit swing engine UE is supported on the vehicle body frame F so as to be swingable about the axis of both the support shafts 52, 52. Meanwhile, a tension rod 53 is provided between the engine E and the vehicle body frame F, and ring-like connection portions 53a, 53b are provided at both ends of the tension rod 53. The connection portion 53a at one end of the tension rod 53 is turnably connected to a mount portion 54 provided in the seat rail 39 and the rear frame 40 on the right side, of the vehicle body frame F, and the connection portion 53b at the other end of the tension rod 53 is turnably connected to the right end of the connecting shaft 51 connecting the crankcase 44 to the link 50. The mount portion 54 includes a support tube 55 extending rearwardly and downwardly from a front portion of the seat rail 39 on the right side with a bracket 56 being in a roughly U-shape opened toward the rear side and attached to the rear end of the support tube 55, and a connecting tube 57 for connection between the rear frame 40 on the right side and the bracket 56. The connection portion 53a at one end of the tension rod 53 is turnably supported on the mount portion 54 by a bolt 58 fixed to the vehicle body frame F in the state of being passed through the bracket 56 and the connecting tube 57. In addition, downwardly drooping support plates 61, 61 are attached to the rear ends of both the seat rails 39 . . . in the vehicle body frame F with upper end portions of shock absorbers 64, 64 being connected to a pair of brackets 63, 63 provided on a support pipe 62 bridgingly provided between both the support plates 61, 61. The lower end portions of both the shock absorbers 64, 64 are connected to a rear end portion of the transmission case 43 and a rear end portion of the swing arm. Brackets 65 . . . are attached to the rear ends, or the lower ends, of both the upper down frames 37 . . . with a main stand 66 being turnably supported by both the brackets 65 . . . . When the main stand 66 is erected, the motor scooter type motorcycle can be made to self-stand with the rear wheel WR off the ground as shown in FIG. 1, and the main stand 66 is stowed so that the rear wheel WR makes contact with the ground at the time of operating the motorcycle. The downstream end of a throttle body 68 is connected to the upper surface of a cylinder head 46 in the engine E through an intake pipe 67 curved toward the rear side from the cylinder head 46, and the upstream end of the throttle body 68 is connected to an air cleaner 69 disposed on the upper side of the continuously variable transmission M in the unit swing engine UE, through a connecting pipe 70 passing on the upper side of the link tube portion 50a of the link 50. A fuel injection valve 74 is attached to the intake pipe 67. In addition, a control box 76 containing a controller for controlling the ignition timing of the engine E and the fuel injection amount of the fuel injection valve 74 is attached to the throttle body 68. An exhaust pipe 77 is connected to the lower surface of the cylinder head 46, and the exhaust pipe 77 is connected to an exhaust muffler 78 disposed on the right side of the swing arm. The fuel injection valve 74 for injecting fuel toward the engine E is supplied with fuel from the fuel tank 28. The fuel tank 28 is disposed in a space surrounded by the left-right pair of upper down frames 37 . . . and the left-right pair of lower down frames 38 . . . in the vehicle body frame F and located immediately on the rear side of the front wheel WR, and is formed to vertically extend over the range from the rear side of a lower portion of the head pipe 27 to lower portions of both the lower down frames 38 . . . . Mount plates 95 . . . for fastening an upper portion of the fuel tank 28 are welded to the inclined portions 38a . . . of both the lower down frames 38 . . . with mount plates 96 . . . for fastening a lower portion of the fuel tank 28 being welded to the horizontal portions 38b . . . of both the lower down frames 38 . . . . A pump unit 97 is contained in a lower portion of the inside of the fuel tank 28. The pump unit 97 is mounted to the fuel tank 28 from the back side of the fuel tank 28 in such a manner so as to be inserted into the fuel tank 28 through a mount hole 98 provided in the back surface of a lower portion of the fuel tank 28. In addition, the pump unit 97 is mounted to the fuel tank 28 with its rotational axis inclined forwardly and downwardly with a fuel filter 99 annexed to the pump unit 97 so as to suck in the fuel present in the fuel tank 28 being disposed at a lowermost portion of the inside of the fuel tank 28. In addition, a float 101 that is moved up and down according to the amount of the fuel in the fuel tank 28 extends from the pump unit 97, and the residual fuel amount detected by the float 101 is sent to the controller 75 in the control box 76 attached to the throttle body 68. The radiator 29 includes a radiator fan 35 disposed at a position spaced rearwardly from the fuel tank 28. The radiator 29 is supported by a support frame 100, which is provided between rear portions of the horizontal portions 38b . . . of both the lower down frames 38 in the vehicle body frame F and rear portions of both upper down frames 37 . . . in the vehicle body frame F. The lower end of a hose 105 extends upwardly and is connected to a reservoir tank 104 connected to the radiator 29 with the upper end of the hose 105 being connected to a water supply port forming member 108 forming a water supply port 107 which can be opened and closed with a cap 106. In addition, the water supply port forming member 108 is supported by the mount portion 54, for mounting to the vehicle body frame F side, of the tension rod 53 provided between the vehicle body frame F and the unit swing engine UE swingably supported on the vehicle body frame F. In other words, the water supply port forming member 108 is supported on the support tube 55 extending rearwardly and downwardly from a front portion of the seat rail 39 on the right side and constituting a part of the mount portion 54. Referring to FIG. 6 also, the luggage box 30 as a luggage containing portion is disposed between rear portions of both the upper down frames 37 . . . in the vehicle body frame F, between both the seat rails 39 . . . , between both the rear frames 40 . . . and on the lower side of the rider's seat 31. The luggage box 30 includes a box main body 110 opened at the top end with a top cover 111 connected to the box main body 110 so as to cover a rear portion of the box main body 110 from the upper side. The luggage box 30 is disposed so as to extend from the lower side of the front end of the rider's seat 31 to the vicinity of upper portions of the rear shock absorbers 64 . . . . For supporting the luggage box 30 on the vehicle body frame F, front support members 112 . . . are welded respectively to intermediate portions of the pair of seat rails 39 . . . in the vehicle body frame F, and rear support members 113 . . . elongate in the front-rear direction are welded respectively to rear portions of both the seat rails 39 . . . . On the other hand, front mount portions 110a . . . mounted on the front support members 112 . . . and rear mount portions 110b . . . mounted on intermediate portions in the longitudinal direction of the rear support portions 113 . . . are provided at both side upper portions of the box main body 110 of the luggage box 30. The front mount portions 110a . . . are respectively fastened to the front support members 112 . . . by bolts 114 . . . , and the rear mount portions 110b . . . are respectively fastened to the rear support members 113 . . . by bolts 115 . . . . The bottom wall of the luggage box 30, i.e., the bottom wall of the box main body 110 is provided with a front helmet containing portion 119 disposed on the lower side of the front seat 32 so as to be capable of containing a helmet H1 therein. A rear helmet containing portion 120 is disposed on the lower side of the rear seat 33 so as to be capable of containing a helmet H2 therein. A substantially flat shallow portion 110c is disposed between the front helmet containing portion 119 and the rear helmet containing portion 120. The front and rear helmet containing portions 119, 120 are each formed in a downwardly bulging shape. In addition, the front edge of the top cover 111 of the luggage box 30 is formed in an arcuate shape bulging rearwardly in a top plan view for permitting the helmet H2 to be contained in the rear helmet containing portion 120. An illumination means 116 for illuminating the inside of the luggage box 30 is attached to the inside surface of the box main body 110, at a portion corresponding to a front portion of the top cover 111. On the lower side of the shallow portion 110c of the luggage box 30, the throttle body 68 and the fuel injection valve 74 are disposed, with their upper end positions being substantially the same. The water supply port 107 of the reservoir tank 104 is disposed adjacent thereto. A first maintenance lid 117 is openably and closably attached to the shallow portion 110c on the upper side of the water support port 107. A rear bulging portion 121 bulging to the rear side relative to the support pipe 62, which is the mount portion for mounting upper portions of the shock absorber 64 . . . to a rear portion of the vehicle body frame F, and the rear end of the rear seat 33 is provided at a rear portion of the luggage box 30. The rear bulging portion 121 bulges rearwardly to substantially the same position as the rear end of a grab rail 118 disposed around the rear seat 33. In addition, a small width portion 121a is provided at the center of a rear portion of the rear bulging portion 121, and tail light units 123 . . . are provided on both sides of the small width portion 121a. A lower portion of the rear bulging portion 121 is disposed on the lower side relative to the support pipe 62, which is the mount portion for mounting upper portions of the rear shock absorbers 64 . . . to a rear portion of the vehicle body frame F. Thus, a raised portion 110d corresponding to the mount portion for mounting the upper portions of the rear shock absorbers 64 to the vehicle body frame F is formed in a manner of partly raising the bottom wall of the luggage box 30, i.e., the bottom wall of the box main body 110. A containing portion 124 with the raised portion 110d between itself and the rear helmet containing portion 120 is formed in the rear bulging portion 121. The rear seat 33 of the rider's seat 31 is formed so as to cover the front portion side of the top cover 111 of the luggage box 30, and is detachably attached to the top cover 111. The upper surface of the top cover 111 is provided with a tetragonal first rib 127 connected endlessly, and a containing space 128 which can be utilized according to the attachment and detachment of the rear seat 33 that is formed on the upper surface of the top cover 111 so as to be surrounded by the first rib 127. In addition, a second rib 129 is connected endlessly while surrounding the first rib 127 and droops from a bottom plate 33a of the rear seat 33. A labyrinth structure surrounding the containing space 128 includes the first and second ribs 127, 129. The grab rail 118 is a metallic member integrally including grip portions 118a. . . disposed on both sides of the rear seat 33 and extending in the front-rear direction with a connection portion 118b for connection between the rear ends of the grip portions 118a . . . . Front portions of both the grip portions 118a are respectively fastened to the rear support members 113 . . . welded to rear portions of the seat rails 39 . . . in the vehicle body frame F, by bolts 134 . . . at two positions (each) on the front and rear sides of fastening portions for fastening the luggage box 30 to the rear support members 113 . . . . The connection portion 118 is integrally connected to the rear ends of both the grip portions 118a . . . so as to be located at a position spaced upwardly from an upper portion of the rear bulging portion 121 of the luggage box 30 and to be at substantially the same height as the upper surface of the rear seat 33. A backrest 135 for holding, from the rear side, a waist portion of the passenger seated on the rear seat 33 is detachably attached to the connection portion 118b. Specifically, a bottom plate 136 of the backrest 135 is integrally provided with a plurality of leg portions 136a . . . which abut on the connection portion 118b of the grab rail 118. Nuts 138 . . . are embedded in the leg portions 136a . . . , and bolts 137 . . . passed through the connection portion 118b of the grab rail 118 from the lower side are screw-engaged and fastened with the nuts 138 . . . , whereby the backrest 135 is detachably attached to the upper surface of a rear portion of the grab rail 118, i.e., the upper surface of the connection portion 118b. In addition, the backrest 135 is formed in a roughly streamline shape provided at its upper surface with a forwardly lowered front inclined surface 135a and a rearwardly lowered inclined surface 135b in side view, and is formed to become narrower in width toward the rear side in a top plan view. In the top plan view, the grab rail 118 and the backrest 135 overlap each other at substantially the entire part thereof. The front seat 32 of the rider's seat 31 is integrally provided at its rear portion with a backrest portion 32a raised upwardly so as to hold, from the rear side, a waist portion of the driver seated on the front seat, and is disposed on the luggage box 30 so as to cover, from the upper side, the front opening portion, not covered with the top cover 111, of the luggage box 30. A front end portion of the front seat 32 is connected to the front end of the luggage box 30 through a hinge pin 139. Namely, the front end portion of the front seat 32 is turnably supported on the luggage box 30 so as to be vertically openable and closable. A roughly U-shaped striker 141 is attached to a rear portion of the bottom plate 140 of the front seat 32. A seat lock mechanism 142, switchable between a seat lock condition for holding the front seat 32 in a closed state by gripping the striker 141 and a seat unlock condition for permitting opening and closing operations of the front seat 32 by releasing the grip on the striker 141, is disposed at a position corresponding to a central portion in the width direction of the rear seat 33 and at a portion of the top cover 111 of the luggage box 30 located between the front and rear seats 32, 33. The seat lock mechanism 142 is engaged with the striker 141, to come into the seat lock condition, when the front seat 32 in the state of being opened upwardly is lowered to close the front opening portion of the luggage box 30. The seat lock mechanism 142 is switched from the seat lock condition to the seat unlock condition by a pulling operation of a power transmission cable 143. The seat lock mechanism 142 is provided on a metallic bridge plate 144 provided between the front ends of both the grip portions 118a . . . of the grab rail 118. The bridge plate 144 is formed so as to come into the gap between the top cover 111 and the rear seat 33 from the front ends of both the grip portions 118a . . . and to extend along a front upper surface of the top cover 111. In addition, a cover 146, provided with a cutout 145 (see FIG. 8) for permitting the striker 141 to be inserted therein and drawn out therefrom, is attached to a front portion at the center in the width direction of the rear seat 33, so as to cover the seat lock mechanism 142 from the upper side in the opened condition of the front seat 32. Referring to FIGS. 7 and 8 also, the fuel tank 28 is disposed in the vicinity of a step floor 159 possessed by the vehicle body cover 34 and on the front side of the luggage box 30. A front bulging portion 122 bulging forwardly to the vicinity of a bottom portion of the fuel tank 28 is provided at a lower portion of the front end of the luggage box 30 so as to be disposed between the fuel tank 28 and the radiator 29. A battery 147 is contained in the front bulging portion 122. Namely, the battery 147 is disposed between the fuel tank 28 and the radiator 29. In addition, electrical equipment 148, 149, 150 and the like are contained in the front bulging portion 122, in addition to the battery 147. A second maintenance lid 151 for partitioning between the front bulging portion 122 and the front helmet containing portion 119 is openably and closably attached to the bottom wall of the box main body 110 of the luggage box 30, and maintenance of the battery 147 and the electrical equipment 148 to 150 in the front bulging portion 122 can be performed by opening the second maintenance lid 151 in the condition where the front seat 32 is opened. In addition, a damper rod 152 for assisting the opening and closing of the front seat 32 by permitting the front seat 32 to be opened with a light force and slowing the closing speed of the front seat 32 at the time of closing is provided between a front portion of the front seat 32 and a front portion of the luggage box 30. A lower portion of the damper rod 152 is contained in the front bulging portion 122, and the second maintenance lid 151 is provided with a slit 153 for passing the damper rod 152 therethrough so as to permit displacements of the damper rod 152 attendant on the opening and closing of the front seat 32. Again in FIG. 1, the vehicle body cover 34 includes a front cover 155 for covering a front portion of the head pipe 27 and an upper portion of the front wheel WF with a left-right pair of front side covers 156 . . . joined to both left and right sides of the front cover 155. An inner cover 157 is connected to the front side covers 156 . . . so as to cover the head pipe 27 from the rear side with leg shields 158 . . . joined to both the front side covers 156 . . . and the inner cover 157 so as to cover the front side of leg portions of the rider seated on the front seat 32. A left-right pair of floor center covers 160 . . . is connected to the leg shields 158 . . . , extending rearwardly and forming the step floors 159 . . . at lower end portions thereof with a left-right pair of floor side covers 161 . . . drooping downwardly from outer edges of the step floors 159 . . . . A left-right pair of passenger steps 162 . . . is provided respectively at rear portions of the step floors 159 . . . with a left-right pair of body side covers 163 . . . disposed on both lateral lower sides of the rider's seat 31, connected to the floor side covers 161 . . . and extending rearwardly. A rear lower cover 164 is connected to rear lower portions of the body side covers 163 . . . with a rear upper cover 165 disposed between the rear bulging portion 121 of the luggage box 30 and a rear portion of the grab rail 118. A rear center cover 166 is connected to the rear upper cover 165 so as to be located between the left-right pair of tail light units 123 . . . and to cover the small width portion 121a of the rear bulging portion 121 of the luggage box 30 from the rear side. By parts of the leg shields 158 . . . and the floor center covers 160 . . . , a floor tunnel portion 167 raised upwardly between both the step floors 159 . . . and is formed so as to be disposed in the range from the rear side of the head pipe 27 to the lower side of the front end of the rider's seat 31 and to be located on the upper side of the fuel tank 28 and the radiator 29. An oil supply lid 169 is openably and closably attached to the floor tunnel portion 167, so as to make it possible to supply oil into the fuel tank 28 by opening an oil supply cap 168 possessed by the fuel tank 28 at its upper end. A hinge cover 170 for covering the hinge portion for joining the front seat 32 to the luggage box 30 is joined to the rear end of the floor tunnel portion 167. Head lights 171 . . . are respectively disposed between both sides of a front portion of the front cover 155 and front portions of the left-right pair of front side covers 156 . . . . Blinkers 172 . . . are respectively disposed on the lower side of the head lights 171 . . . and at front portions of both the front side covers 156 . . . . In addition, a panel 173 for arranging meters is joined to the front cover 155, both the front side covers 156 . . . , the inner cover 157 and upper portions of the leg shields 158 . . . . A meter visor 173a is integrally provided at a front portion of the panel 173 so as to rise upwardly. Further, a windshield 174 is disposed on the front side of the meter visor 173a. A front fender 175 for covering the front wheel WF from the upper side is supported by the front fork 25. The steering handle 26 is fitted with a left-right pair of rearview mirrors 176 . . . , an audio operating switch case 177, a switch case 178 for operating lamps or the like. A plug maintenance lid 180 for performing maintenance of an ignition plug 179 of the engine E is openably and closably attached to the left floor center cover 160 of the left-right pair of the floor center covers 160 . . . , at a position on the front side of the passenger step 162. A license plate 182, a reflector 183 and a license light 184 are attached to a rear fender 181 for covering the rear wheel WR from the rear side. The rear fender 181 is mounted to the rear bulging portion 121 of the luggage box 30 together with the left-right pair of tail light units 123 . . . , the rear upper cover 165 and the rear center cover 166. In addition, a pair of ribs 110e . . . functioning as rear fender are projectingly provided on the lower surface of the box main body 110 of the luggage box 30 on the front side of the rear fender 181, so as to be disposed on both left and right sides of the rear wheel WR, as shown in FIG. 5. In FIGS. 9 to 12, the inner cover 157 is provided with a left front containing portion 191 and a right front containing portion 192 at an interval therebetween in the vehicle body width direction. The left front containing portion 191 is configured in a drawer type including a containing case 193 which can be drawn out of the inner cover 157 and removed. Referring to FIGS. 13 and 14 also, the containing case 193 is composed of a case main body 194 formed, for example, of a synthetic resin in a rectangular box-like shape opened at an upper portion. A decorative cover 195, as a cover member, is attached to the outer end of the case main body 194. In addition, the inner cover 157 is provided with a rectangular opening portion 196 for inserting the containing case 193 therein and drawing out the containing case 193 therefrom, and is integrally provided with a storing wall 197 formed in a rectangular tubular shape in connection with the opening portion 196. The inner end of the storing wall 197 is closed with an end wall 197a. Movable rails 198, 198 extending in the front-rear direction are respectively fixed to both side lower portions of the case main body 194 with support portions 198a, 198a formed in a roughly U-shape opened downwardly and being integrally formed at portions, exclusive of front portions along the vehicle body front-rear direction, of the upper ends of the movable rails 198 . . . . On the other hand, fixed rails 200, 200 extending in the front-rear direction in correspondence with the movable rails 198 . . . are fixed to both inside surfaces of the storing wall 197, and rollers 199, 199 for mounting the support portions 198a . . . of the movable rails 198 . . . are respectively rotatably supported on rear portions of the fixed rails 200 . . . along the vehicle body front-rear direction. On the other hand, sliders 190 for sliding contact with the lower surfaces of upper portions of both the fixed rails 200, 200 are fixed to front portions of the movable rails 198 . . . along the vehicle body front-rear direction. The containing case 193 is inserted via the opening portion 196 into the storing wall 197 so that the containing case 193 can be slid between a fully closed position where the decorative cover 195 of the containing case 193 is substantially flush with the back surface of the leg shield 158 and a fully opened position where the containing case 193 is mostly drawn out of the storing wall 197, and wherein the entire part of the containing case 193 can be drawn out of the inner cover 157. In addition, the containing case 193 covers the head pipe 27 from the left side when in the fully closed position. Meanwhile, the end wall 197a of the storing wall 197 is provided with a maintenance window 201 for permitting maintenance work for, for example, replacing a bulb 171a of the head light 171 located on the front side of the end wall 197 when the containing case 193 is drawn out from the leg shield 158. The window 201 is covered with a detachable lid 202. A projecting portion 193a projecting inwardly in the vehicle body width direction is provided on the outer end side of the containing case 193. The storing wall 197 is provided with a recessed portion 197b for containing the projecting portion 193a when the containing case 193 is stored in the fully closed position, so as to be opposed to the head pipe 27 from the rear side. Referring to FIG. 15, a case lock mechanism 208 for locking the containing case 193 in the fully closed position is provided between the containing case 193 and the inner cover 157. The case lock mechanism 208 includes a pin-like striker 209 attached to the lower surface of the case main body 194 of the containing case 193 with a catcher 210 turnably supported on the inner cover 157 side so as to catch the striker 209 according to the sliding of the containing case 193 toward the closing side to the fully closed position. An engaging member 211 is capable of being engaged with the catcher 210 so as to hold the catcher 210 in the state of catching the striker 209 with a coil spring 212 for biasing the engaging member 211 in the direction for engagement with the catcher 210. A support frame 214 having a guide recessed portion 213 for inserting the striker 209 therein according to the sliding of the containing case 193 toward the closing direction to the fully closed position is bridgingly disposed between the pair of fixed rails 200, 200 fixed to the inner cover 157, so as to be opposed to the lower surface of the case main body 194. The catcher 210 disposed on the lower side of the support frame 214 is turnably supported on the support frame 214 through a support pin 216. The catcher 210 is provided with an engaging recessed portion 216 for engaging therein the striker 209 inserted into the guide recessed portion 213. The engaging member 211 is disposed on the lower side of the support frame 214, on the opposite side of the catcher 210 with respect to the guide recessed portion 213, and is turnably supported on the support frame 214 through a support pin 217 parallel to the support pin 216. The coil spring 212 is disposed in a compressed state between the catcher 210 and the engaging member 211 so as to display a spring force for turningly biasing the catcher 210 counterclockwise in FIG. 15 and for turningly biasing the engaging member 211 clockwise in FIG. 15. The support frame 214 is provided with a stopper 218 for restricting the turning end of the counterclockwise turning of the catcher 210 under the spring force of the coil spring 212, and a stopper 219 for restricting the turning end of the clockwise turning of the engaging member 211 under the spring force of the coil spring 212. In the condition where the striker 209 is released from the guide recessed portion 213 as shown in FIG. 16, the catcher 210 has been turned to the turning restriction end for abutting the stopper 218 by the spring force of the coil spring 212. In this condition, the opening end of the engaging recessed portion 215 is at a position for fronting on the guide recessed portion 213. In addition, a locking step portion 210a fronting on the front side along the turningly biasing direction (counterclockwise direction in FIGS. 15 and 16) by the spring force of the coil spring 212 is provided at a portion, on the engaging member 211 side, of the catcher 210. On the other hand, the engaging member 211 is provided with an engaging projecting portion 211a for restricting the turning of the catcher 210 in the turningly biasing direction of the catcher 210 by engagement with the locking step portion 210a. When the striker 209 is released from the guide recessed portion 213 as shown in FIG. 16 in the condition where an unlocking force is not exerted on the engaging member 211, the engaging member 211 is in such a position that the engaging projected portion 211a is disengaged from the locking step portion 210a. When the striker 209 is moved from the position indicated in FIG. 16 to the position of coming into the guide recessed portion 213 as shown in FIG. 15, the catcher 210 abuts on the engaging projected portion 211a of the engaging member 211 to turn the engaging member 211 counterclockwise against the spring force of the coil spring 212, thereby riding over the engaging projected portion 211a. After the catcher 210 has ridden over the engaging projected portion 211a, the engaging member 211 is turned clockwise by the spring force of the coil spring 212 to the side for abutting on the stopper 219, and the engaging projected portion 211a is engaged with the locking step portion 210a of the catcher 210. In this condition, even if an external force in an opening direction is exerted on the containing case 193 in order to turn the catcher 210 counterclockwise through the striker 209, the clockwise turning of the engaging member 211 having the engaging projecting portion 211a engaged with the locking step portion 210a is hampered by the stopper 219. Thus, the catcher 210 is not be turned counterclockwise in FIG. 15 so as to release the striker 209 from the engaging recessed portion 215, and the fully closed condition of the containing case 193 is locked by the case lock mechanism 208. The lock condition of the case lock mechanism 208 can be released (unlocked) by exerting on the engaging member 211 an unlocking force for turning the engaging member 211 in the direction for releasing it from the stopper 219, i.e., in the counterclockwise direction. The unlocking force is exerted from a first electric actuator 221 through the power transmission cable 220 connected to the engaging member 211. The first electric actuator 221 displays the unlocking force in the direction of pulling the power transmission cable 220 when operated. When the power transmission cable 220 is pulled by the first electric actuator 221 in the lock condition of the case lock mechanism 208, the engaging member 211 is turned counterclockwise so as to cause the engaging projected portion 211a to ride over the locking step portion 210a while turning the catcher 210 clockwise against the spring force of the coil spring 212. When the engaging projected portion 211a has ridden over the locking step portion 210a, the spring force of the coil spring 212 acts so that the catcher 210 is turned counterclockwise to push out the striker 209 in the direction for releasing from the guide recessed portion 213 as shown in FIG. 16, and the catcher 210 abuts on the stopper 218. More specifically, when the first electric actuator 221 is operated in the lock condition of the case lock mechanism 208, an unlocking force is exerted on the case lock mechanism 208 to release the lock condition, whereby the striker 209, i.e., the containing case 193 is slightly pushed out toward the opening side from the fully closed position by the spring force of the coil spring 212 possessed by the case lock mechanism 208. In addition, a spring means 222 for providing a spring biasing of the containing case 193 in the direction of a fully opened position in the condition where the containing case 193 is in the fully closed position is provided between the containing case 193 and the inner cover 157. The spring means 222 includes a tube body 223 extending in the vehicle body front-rear direction, a rod 224 which is slidably fitted in the tube body 223 so as to permit relative movements in the axial direction within a limited range in the vehicle body front-rear direction and a part of which projects from the rear end of the tube body 223 along the vehicle body front-rear direction, and a spring (not shown) provided between the tube body 223 and the rod 224 for the purpose of biasing the rod 223 toward the rear side in the vehicle body front-rear direction. Between the pair of fixed rails 200, 200 on the front side relative to the support frame 214 along the vehicle body front-rear direction, a front support frame 225 is bridgingly disposed so as to be located on the lower side relative to the containing case 193 situated in the fully closed position. The front end of the tube body 223 is fixedly connected to the front support frame 225, and an intermediate portion in the axial direction of the tube body 223 is held by a holding member 227 mounted to the support frame 214. Further, a rear support frame 226 located on the lower side of the containing case 193 is bridgingly disposed between the pair of movable rails 198, 198 on the rear side relative to the support frame 214 along the vehicle body front-rear direction. The rear support frame 226 is provided with an abutting plate portion 226a so as to abut on the rear end of the rod 224 at a position near the fully closed position when the containing case 193 is moved toward the fully closed position side. With the spring means 222 as above, when the lock condition of the case lock means 208 is released (unlocked) in the condition where the containing case 193 is in the fully closed position, the spring force of the coil spring 212 of the case lock mechanism 208 and the spring biasing force by the spring means 222 are exerted on the containing case 193. The containing case 193 is slightly slid from the fully closed position toward the opening side, after which it suffices to draw out the containing case 193. In FIGS. 17 and 18, a holding mechanism 230, for temporarily holding the containing case 193 at an intermediate position between the fully closed position and the fully opened position, in this embodiment at a roughly central position between the fully closed position and the fully opened position, when the containing case 193 is opened from the fully closed position, is provided between the containing case 193 and the inner cover 157. The position where the containing case 193 is temporarily held by the holding mechanism 230 is set so that, in the condition where a person with a height of not more than 175 cm (a range covers 90% of the population of Japan) is seated on the front seat 32, a drivers' knees do not make contact with the containing case 193 (see the indication by chain lines in FIG. 1). The holding mechanism 230 includes a locking shaft 232 extending in the vehicle body width direction and supported by a support member 231 attached to the front end of the fixed rail 200 located on the right side (as seen from the rear side in the vehicle body front-rear direction) of the left-right pair of fixed rails 200, 200 fixed to the inner cover 157. A swingable engaging member 235 is swingably supported on a bracket 233 attached to the rear support frame 226 fixed to the containing case 193, through a support shaft 234 having an axis parallel to the locking shaft 232. A torsion spring 236 is provided between the bracket 233 and the swingable engaging member 235 so as to bias the swingable engaging member 235 counterclockwise in FIGS. 17 and 18. The locking shaft 232 is supported by the support member 231 so that its one end portion projects from the fixed rail 200 to the containing case 193 side. In addition, the swingable engaging member 235 is integrally provided with an engaging portion 235a projecting from the bracket 233 to the fixed rail 200 side, and is turnably supported on the bracket 233. The turning end of the swingable engaging member 235 turningly biased in the direction for upwardly turning the engaging portion 235a, i.e., in the counterclockwise direction in FIGS. 17 and 18 by the spring force of the torsion spring 236 is restricted by the abutment of the swingable engaging member 235 on the rear support frame 226. The engaging portion 235a is provided at its upside edge with an engaging recessed portion 238 for spring engagement with the locking shaft 232, a front guide surface 239 is disposed on the front side relative to the engaging recessed portion 238 along the vehicle body front-rear direction, and a rear guide surface 240 is disposed on the rear side relative to the engaging recessed portion 238 with the engaging recessed portion 238 between itself and the front guide surface 239. The front guide surface 239 is formed as an inclined surface inclined rearwardly and upwardly, while the rear guide surface 240 is formed as an inclined surface inclined rearwardly and downwardly at an inclination smaller than the inclination of the front inclined surface 239, in the condition where the swingable engaging member 235 is at the end of turningly being biasing by the torsion spring 236. In addition, of the engaging recessed portion 238, the inside surface on the rear inclined surface 240 side is formed so as to be inclined substantially in parallel to the front guide surface 239 in the condition where the swingable engaging member 235 is at the end of the turningly biasing by the torsion spring 236. With the holding mechanism 230 as above, when the containing case 193 present in the fully closed position is openingly operated, the locking shaft 232 present at the fixed position makes contact with the rear guide surface 240, whereby the swingable engaging member 235 is turingly driven in the direction for pressing down the engaging portion 235a against the spring force of the torsion spring 236, i.e., in the clockwise direction in FIG. 18. When the containing case 193 is further slid toward the fully opened position side while keeping the rear guide surface 240 in sliding contact, the locking shaft 232 drops from the rear guide surface 240 into the engaging recessed portion 232, whereby the swingable engaging member 235 is turned in the direction for pushing up the engaging portion 235a, i.e., in the counterclockwise direction in FIG. 18 by the spring force of the torsion spring 236, and the engaging recessed portion 238 is brought into spring engagement with the locking shaft 232, whereby the containing case 193 is temporarily held. Such a temporarily held condition can be released by forcibly turning the swingable engaging member 235 as indicated by chain lines in FIG. 18 against the spring force of the torsion spring 236. Upon this operation, the spring engagement of the locking shaft 232 with the engaging recessed portion 238 is released, resulting in that the containing case 193 being slidingly operated toward the fully opened position side. Upon an operation to push in the containing case 193 present at the fully opened position toward the fully closed position, the locking shaft 232 abuts on the front guide surface 239 in the course of the process. In this case, since the front guide surface 239 is an inclined surface inclined forwardly and downwardly, a further pushing-in of the containing case 193 turns the swingable engaging member 235 so as to push down the engaging portion 235a, whereby the locking shaft 232 is caused to drop into the engaging recessed portion 238. Since the inside surface of the engaging recessed portion 238 on the rear inclined surface 240 side is inclined substantially in parallel to the front guide surface 239, a further pushing-in of the containing case 193 causes the locking shaft 232 to turn the swingable engaging member 235 so as to further push down the engaging portion 235a, thereby making sliding contact with the rear guide surface 240, so that the containing case 193 can be pushed in to the fully closed position. Meanwhile, at the time of releasing the temporary holding of the containing case 193 by the holding mechanism 230, it suffices to turningly operate a synthetic resin-made hold release operating member 237 fastened to the swingable engaging member 235 in the direction indicated by an arrow in FIG. 18. The hold release operating member 237 is disposed on the lower surface of the containing case 193 at a position near the vehicle body center line C and near the vehicle body rear side. A steering handle lock module 241 capable of disabling the steering operation on the steering handle 26 is disposed in the vicinity of the head pipe 27 on the opposite side of the left front containing portion 191, and the right front containing portion 192 is disposed so that the steering handle lock module 241 is located between itself and the left front containing portion 191. In FIG. 19, the steering handle lock module 241 enables the steering operation on the steering handle 26 and enables the starting of the engine E, according to an operation, based on predetermined conditions, of a smart entry knob 242 disposed on the inner cover 157 between the left and right front containing portions 191 and 192. The above-mentioned first electric actuator 221 is disposed in the steering handle lock module 241. In FIG. 20, the right front containing portion 192 has a structure in which a containing recessed portion 244 formed in the inner cover 157 is openably and closably covered with a lid member 245 hinged to the inner cover 157. The containing recessed portion 244 is formed to be smaller than the containing case 193 of the left front containing portion 191 and to be slightly narrowed as the front end is approached. The lid member 245 is hinged to the inner cover 157 through a pivotal shaft 256 so as to be turnable between an opening position for opening the containing recessed portion 244 by being turned downwardly as indicated by chain lines in FIG. 20 and a closure position for closing the containing recessed portion 244 as indicated by solid lines in FIG. 20. A handle 247 for enabling turning operations is turnably attached to the lid member 215. A plurality of lock release operating buttons for respectively releasing the lock conditions of a plurality of containing portions inclusive of the left front containing portion 191, in this embodiment the left front containing portion 191 and the luggage box 30, are disposed on the inner cover 157 on the lower side of the smart entry knob 242, i.e., on a lateral side of the left front containing portion 191 and between the left front containing portion 191 and the right front containing portion 192. In this embodiment, a first lock release operating button 248a for the left front containing portion 191 and a second lock release operating button 249a for the luggage box 30 are arranged at positions set off to either the left or right side (in this embodiment, the right side) from the vehicle body center line C, in a vertically aligned pattern, with the first lock release operating button 248a at the lower position. The first and second lock release operating buttons 248a and 249a constitute parts of first and second lock release switches 248 and 249 for changing the switching modes by operating the operating buttons 248a and 249a. The first and second lock release switches 248, 249 are attached to the inner cover 157 with the first and second lock release operating buttons 248a, 249a fronting on the outside surface of the inner cover 157, and the first and second lock release operating buttons 248a, 249a are formed to be horizontally elongate. In addition, the first lock release operating button 248a for releasing the lock condition of the left front containing portion 191, the case lock mechanism 208, and the first electric actuator 221 for exerting an unlocking force on the case lock mechanism 208 are disposed at substantially the same height. In FIG. 21, the controller 75 contained in the control box 76 attached to the throttle body 68, the steering handle lock module 241, and the first and second lock release switches 248, 249 constitute parts of a smart entry system. The steering handle lock module 241 includes a cylinder lock 250 which can be turned by the knob 242 and which releases the locking of the steering handle 26 to the head pipe 27 when turned, a lock solenoid 251 capable of disabling the turning of the cylinder lock 250, and a main switch 252 switchingly operated according to the turning of the cylinder lock 250. The lock solenoid 251 is controlled by a control unit 253. The control unit 253 controls a transmission antenna 255 so as to transmit a signal for prompting the transmission of an ID signal from a normal portable transmitter 256 carried by the vehicle user. The result of the signal reception by a reception unit 257 for receiving a signal from the portable transmitter 256 is inputted to the control unit 253. When it is confirmed in the control unit 253 that the ID signal transmitted from the portable transmitter 256 is a predetermined signal, the control unit 253 operates the lock solenoid 251 so as to permit the cylinder lock 250 to be turned by use of the knob 242. In addition, when it is confirmed in the control unit 253 that the ID signal sent from the portable transmitter 256 is a predetermined signal, the control unit 253 enables a control of the operation of the engine E by the controller 75 according to the conduction of the main switch 252, operates the first electric actuator 221 according to a signal from the first lock release switch 248 in accordance with the operation of the first lock release operating button 248a in the conduction condition of the main switch 252, and operates a second electric actuator 258 according to a signal from the second lock release switch 249 in accordance with the operation of the second lock release operating button 249a in the conduction condition of the main switch 252. The second electric actuator 258 pulls the power transmission cable 143 (see FIGS. 5 and 6) according to the operation thereof, to thereby release the lock condition of the seat lock mechanism 142. Further, when it is confirmed in the control unit 253 that the ID signal transmitted from the portable transmitter 256 is a predetermined signal, the control unit 253 operates the lock release operating button 248a, whereby the case lock mechanism 208 for the containing case 193 is released, with the result that the containing case 193 can be drawn out to a position in the range from the fully closed position to an intermediate held position. Under the drawn-out condition, a lock release operating member 272 can be operated. The reception unit 257 is disposed in the luggage box 30 or in the rider's seat 31. In this embodiment, a reception unit containing portion 110f formed by recessing downwardly a part of the shallow portion 110c of the luggage box 30 is provided in the luggage box 30, and the reception unit 257 is contained in the reception unit containing portion 110f. In addition, the shallow portion 110c is provided with the first maintenance lid 117 for performing a maintenance concerning the engine E disposed on the lower side of the luggage box 30, in an openable and closable manner. The reception unit 257 is contained in the reception unit containing portion 110f so as to be covered with a part of the first maintenance lid 117. On the other hand, the transmission antenna 255 is disposed at a position remote from the steering handle lock module 241. In this embodiment, the transmission antenna 255 is disposed on the upper side of the steering handle lock module 211, for example, directly under the panel 173 constituting a part of the vehicle body cover 34. In FIG. 22, the oil supply lid 169 is fastened to a frame member 261 extending in the vehicle body front-rear direction by a plurality of screw members 262 . . . . A hinge arm 263 that is in connection with the rear end of the frame member 261 along the vehicle body front-rear direction is turnably supported to a support plate 264 fixed to the vehicle body frame F and to a bracket 265 fixed to the hinge cover 170, through a support shaft 266. A locking portion 267 is provided at a front end portion of the frame member 261 along the vehicle body front-rear direction with a lid lock mechanism 268 for locking the closed condition of the oil supply lid 169 being engaged with the locking portion 267, thereby holding the oil supply lid 169 in the locked state. The lid lock mechanism 268 includes a rod 270 extending in the vehicle body front-rear direction on the lower side of the floor tunnel portion 167 on the front side of the oil supply lid 169, and a spring 271 for biasing the rod 270 toward the rear side in the vehicle body front-rear direction. A synthetic resin-made cap 269 capable of engagement with the locking portion 267 is mounted to the rear end of the rod 270. The rod 270 receives a force in the direction for releasing the engagement of the cap 269 with the locking portion 267, i.e. in the direction toward the front side, against the spring force of the spring 271 by the operation of the lock release operating member 272. The lock release operating member 272 is disposed on the inner cover 157 at a position between the left and right front containing portions 191 and 192 and on either the left or right side (in this embodiment, the left side) from the vehicle body center line C, so as to be covered with the decorative cover 195 disposed on the inner cover 157 when the decorative cover 195 is in a closed condition. In this embodiment, the lock release operating member 272 is disposed on the inner cover 157 at a position set off from the containing case 193 of the left front containing portion 191 and at least partly overlapped with the head pipe 27, as viewed from the rear side in the vehicle body front-rear direction. The decorative cover 195 is attached to the containing case 193 so as to cover the lock release operating member 272 when the containing case 193 is in the fully closed position. More specifically, the projecting portion 193a projecting inwardly in the vehicle body width direction is provided on the outer end side of the containing case 193, and the decorative cover 195 is attached to the outer end of the containing case 193. Therefore, a support case 274 is attached to the inner cover 157 at such a position so as to be capable of being covered with the projecting portion 193a. An upper portion of the lock release operating member 272 is turnably supported on the support case 274. In addition, the rod 270 is integrally provided at its front portion with a bent portion 270a bent towards the lock release operating member 272 side, and the bent portion 270a is connected to a lower portion of the lock release operating member 272. Therefore, under the condition where the containing case 193 in the left front containing portion 191 is drawn out to an intermediate opened position (the chain-line position in FIG. 22) restricted by the holding mechanism 230 or to a further opened position, when the user pushes in the lock release operating member 272 by the rider's finger placed on the back side of the projecting portion 193a and thereby turns the lock release operating member 272 in the direction of an arrow in FIG. 22, the rod 270 can be operated in such a direction that the cap 269 is released from the locking portion 267. In FIG. 23, a rod support frame 278 is attached to the inside surface of the floor tunnel portion 167 on the front side relative to the oil supply lid 169, by a screw member 279. An intermediate portion of the rod 270 is held by the rod support frame 278 so as to be movable along the axial direction. In addition, a stop ring 275 is mounted to the rod 270 inside the support frame 278, and the above-mentioned coil-shaped spring 271 surrounding the rod 270 is disposed in a compressed state between an annular spring receiving member 276 capable of engaging with the stop ring 275 from the front side and capable of abutting on and engaging with the rear wall of the rod support frame 278 and an annular spring receiving member 277 capable of abutting on and engaging with the front wall of the rod support frame 278. Meanwhile, at the time of closing the oil supply lid 169 being in an opened state, it is necessary to push the rod 270 of the lid lock mechanism 268 forwards. In this case, since a pushing plate portion 267a for pushing the cap 269 at the rear end of the rod 270 towards the rear side according to the closing operation on the oil supply lid 169 is integrally provided in connection with the locking portion 267 on the oil supply lid 169 side, closing the oil supply lid 169 from the opened state causes the pushing plate portion 267a to push the rod 270 towards the front side through the cap 269. Wen the oil supply lid 169 is turned to the closed position, the rod 270 is moved rearwardly by the spring force of the spring 271, and the cap 269 is engaged with the locking portion 267, whereby the closed condition of the oil supply lid 169 is locked. Now, the functions of this embodiment will be described below. At a rear portion of the luggage box 30, which includes the front helmet containing portion 119 disposed on the lower side of the front seat 32 possessed by the tandem type rider's seat 31 and the rear helmet containing portion 120 disposed on the lower side of the rear seat 33 possessed by the rider's seat 31, there is provided the rear bulging portion 121 bulging to the rear side relative to the rear end of the rear seat 33 and the support pipe 62 which is the mount portion for mounting an upper portion of the rear shock absorber 64 to a rear portion of the vehicle body frame F. Therefore, the inside volume of the containing box 30 can be enlarged while ensuring that long things such as golf clubs extending to the rear side relative to the rear end of the rider's seat 31 can be contained in the luggage box 30. Moreover, small things other than the helmet can also be contained in the rear portion of the luggage box 30, so that things which are used less frequently, such as tools, can be suitably contained in the rear portion of the luggage box 30. In addition, since the rear bulging portion 121 bulges rearwardly to substantially the same position as the rear end of the grab rail 118 disposed around the rear seat 33, the inside volume of the luggage box 30 can be more enlarged, and the rear portion of the luggage box 30 can be protected by the grab rail 118. In addition, since the small width portion 121a entering between the left and right tail light units 123 . . . in the top plan view is provided at a rear portion of the rear bulging portion 121, the inside volume of the luggage box 30 can be enlarged by utilizing effectively the space generated between the left-right pair of tail light units 123 . . . . Thus, the formation of a space for replacement of bulbs of the tail light units 123 . . . is facilitated. Meanwhile, the luggage box 30 has the top cover 111 disposed on the lower side of the rear seat 33, and the containing space 128 capable of being utilized according to the attachment and detachment of the rear seat 33 is formed on the upper surface of the top cover 111. Therefore, a space for containing small things, other than the inside of the luggage box 30, can be secured while obviating an increase in the number of component parts and a complication of the structure. In addition, since the containing space 128 is formed inside the first rib 127 erected on the top cover 111 and connected endlessly and the second rib 129 connected endlessly so as to cooperate with the first rib 127 in forming a labyrinth structure droops down from the bottom plate 33a of the rear seat 33, penetration of rainwater, dust or the like into the containing space 128 from the surroundings can be prevented with a simple structure. Moreover, since the illumination means 116 for illuminating the inside of the luggage box 30 is attached to the inside surface of the luggage box 30 at a portion corresponding to a front portion of the top cover 111, the inside of a rear portion of the luggage box 30 which tends to be darkened due to the presence of the top cover 111 can be effectively illuminated without being obstructed by the things contained in the rear portion of the luggage box 30. Further, the inside surface of the luggage box 30 is easy to check visually, at the portion corresponding to the front portion of the top cover 111. Thus, it is possible to easily confirm the failure of a bulb of the illumination means 116 and similar problems. In addition, since the rear upper cover 165 and the rear center cover 166 for covering the rear bulging portion 121, the left-right pair of tail light units 123, and the rear fender 181 are attached to the rear bulging portion 121, a plurality of members disposed in the surroundings of a rear portion of the luggage box 30 can be removed at a stroke by simply detaching the wiring for the tail light units 123 . . . , leading to an excellent maintainability. The luggage box 30 includes the shallow portion 110c disposed between the front helmet containing portion 119 and the rear helmet containing portion 120. The throttle body 68 fitted with the control box 76 containing the controller 75 and the fuel injection valve 74 are disposed on the lower side of the shallow portion 110c so that their upper end positions are substantially the same. Therefore, by making a flat shallow portion 110c between the front and rear helmet containing portions 119 and 120, the shallow portion 110c can be effectively utilized as a containing portion, and a part of the intake system of the engine E can be effectively disposed in the space on the lower side of the shallow portion 110c. A lower portion of the rear bulging portion 121 is disposed on the lower side relative to the mount portion for mounting an upper portion of the shock absorber 64 to a rear portion of the vehicle body frame F for forming, in the rear bulging portion 121, the containing portion 124 so that raised portion 110d formed by partly raising the bottom wall of the luggage box 30 upwardly is located between the containing portion 124 and the rear helmet containing portion 120. In addition, the rear helmet containing portion 120 and the containing portion 124 on the rear side relative to the rear helmet containing portion 124 are partitioned from each other by the raised portion 110d, whereby enhanced convenience in use can be contrived, and movements of small things contained in the containing portion 124 on the rear side can be inhibited. In addition, since the fuel tank 28 formed to be elongated in the vertical direction in a side view is disposed on the front side of the luggage box 30 and the luggage box 30 is provided at a lower portion of its front end with the front bulging portion 122 bulging forwardly to the vicinity of a bottom portion of the fuel tank 28, a front portion of the luggage box 30 can be formed deep to facilitate containment of long things. Thus, the capacity of the luggage box 30 can be enlarged. Moreover, since the battery 147 and other electrical equipments 148 through 150 are contained in the front bulging portion 122, the battery 147 and the electrical equipments 148 through 150 can be contained in the luggage box 30 without obstructing the containment of the helmet H1 and the like. Further, the second maintenance lid 151 for partitioning the inside of the front bulging portion 122 and the front helmet containing portion 119 from each other is openably and closably attached to the luggage box 30, whereby the things contained in the front bulging portion 122 and the helmet H1 contained in the front helmet containing portion 119 can be prevented from being damaged through mutual contact. Further, since a lower portion of the damper rod 152, extending vertically so as to assist the opening and closing operations of the front seat 32, is contained in the front bulging portion 122, it is unnecessary to secure a space for disposing the damper rod 152 in the outside of the luggage box 30. Moreover, it is possible to prevent the damper rod 152 from obstructing the positioning of things into the luggage box 30 and to minimize the possibility of the exposure of the damper rod 152 to the exterior when the front seat 32 is opened, thereby enhancing the appearance quality. The fuel tank 28 and the radiator 29 are disposed on the lower side of the floor tunnel portion 167 formed by a part of the vehicle body cover 34 covering the vehicle body frame F. The vehicle body frame F includes the head pipe 27, the left-right pair of upper down frames 37 . . . extending rearwardly and downwardly from the head pipe 27, and the left-right pair of lower down frames 38 . . . having the inclined portion 38a extending rearwardly and downwardly from the head pipe 27 on the lower side relative to the connection portion for connection of the upper down frames 37 . . . to the head pipe 27. The fuel tank 38, extending vertically over the range from the rear side of a lower portion of the head pipe 27 to lower portions of both the lower down frames 38 . . . , is disposed in the space surrounded by both the upper down frames 37 . . . and both the lower down frames 38 . . . and being immediately on the rear side of the front wheel WF. Therefore, since the fuel tank 28, elongate vertically, is disposed immediately on the rear side of the front wheel WF, it is possible to prevent the portion corresponding to a lower portion of the head pipe 27 from becoming a dead space, and to dispose component parts by effectively utilizing the space on the lower side of the floor tunnel portion 167. In addition, since the fuel tank 28 having a comparatively large weight is disposed close to the front wheel WF, the distribution load of the front wheel WF can be enhanced, and enhanced steering performance can be contrived. In addition, the fuel tank 28 is elongate vertically and can provide a comparatively large residual amount of the height in the condition where the residual fuel amount is small, so that where the pump unit 97 is annexed to the fuel tank 28. In this embodiment, the structure is advantageous for suction into the pump. In addition, since the radiator 29 is disposed on the rear side of the fuel tank 28 and the battery 147 is disposed between the radiator 29 and the fuel tank 28, the vertically elongated shape of the fuel tank 28 permits the space on the rear side of the fuel tank 28 to be set comparatively wide. Thus, the battery 147 having a large weight can be disposed at the center in the vehicle body front-rear direction, which contributes to enhancement in the drivability. In addition, the arrangement of the battery 147 between the radiator 29 radiating heat and the fuel tank 28 prevents the heat coming from the radiator 29 from influencing the fuel tank 28. Since the pump unit 97 contained and disposed in a lower portion of the fuel tank 28 is attached to the fuel tank 28 from the back side of the fuel tank 28, the pump unit 97 can be attached to the fuel tank 28 so that it will not be influenced by bumps present in the road surface. Moreover, since the pump unit 97 is attached to the fuel tank 28 in the posture of having its rotational axis inclined forwardly and downwardly, a suction port of the pump unit 97 can be set as close as possible to a lower portion of the fuel tank 28. Thus, the dead residual amount of the fuel in the fuel tank 28 can be minimized. In addition, the water supply port 107 for the reservoir tank 104 of the radiator 29 is disposed on the lower side of the first maintenance lid 117 detachably attached to the bottom wall of the luggage box 30 disposed on the lower side of the rider's seat 31. Therefore, by disposing the radiator 29 on the rear side of the fuel tank 28, it is easy to set the water supply port 107 of the reservoir tank 104 to front on a bottom portion of the rider's seat 31, thereby disposing the water supply port 107 to be higher than in the case of fronting on the step floor 159 directly above the reservoir tank 104 or the like. Thus, it is possible to provide better operability in supplying water. Moreover, since the water supply port forming member 108 for forming the water supply port 107 is supported on the mount portion 54, for mounting to the vehicle body frame F side, of the tension rod 54 provided between the vehicle body frame F and the unit swing engine UE swingably supported on the vehicle body frame F, the need to apply a special contrivance for supporting the water supply forming member 108 can be eliminated. Thus, the water supply port forming member 108 can be supported by the vehicle body frame F. Furthermore, the fuel from the fuel tank 28 is supplied to the fuel injection valve 74, and the fuel in the fuel tank 28 can be effectively supplied to the fuel injection valve 74 by use of the pump unit 97 biased by the fuel tank 28 having such a structure that the residual amount of height in the condition where the residual fuel amount is small is comparatively high. The electric motor 42 for varying the speed change ratio of the continuously variable transmission M interposed between the engine E and the rear wheel WR is disposed on the lower side of the passenger step 162 provided at a rear portion of the step floor 159 of the vehicle body cover 34. The arrangement of the electric motor 42 at a comparatively low position contributes to the lowering of the center of gravity of the motorcycle. In addition, since the continuously variable transmission M is of the belt type for constituting the unit swing engine UE together with the engine E in which the axis of the cylinder 45 is substantially horizontal and the electric motor 42 is disposed on the front side relative to the continuously variable transmission M and on a lateral side of the cylinder 45, the electric motor 42 can be protected by the cylinder 45 of the engine E and the continuously variable transmission M. Moreover, since the vehicle body frame F is provided with the support frame 41 for supporting the step floor 159 from the lower side and the electric motor 42 is disposed on the lower side relative to the support frame 41, the electric motor 42 can be more effectively protected by the support frame 41 which is high in rigidity. The grab rail 118 is mounted to a rear portion of the vehicle body frame F, and the backrest 135 which is formed in a roughly streamline shape having at its upper surface the front inclined surface 135a inclined forwardly and downwardly in the side view and the rear inclined surface 135b inclined rearwardly and downwardly in the side view and which is mounted to the upper surface of a rear portion of the grab rail 118 is disposed on the rear side of the rear seat 33 possessed by the rider's seat 31. Therefore, the waist portion of the passenger on the rear seat 33 can be securely held by the front inclined surface 135a inclined forwardly and downwardly, of the upper surface of the backrest 135, and the roughly streamline shape in the side view enhances the appearance quality of the backrest 135 and promises an enhanced aerodynamic performance. In addition, since the rear inclined surface 135b that is inclined rearwardly and downwardly of the upper surface of the backrest 135 can be utilized, luggage projecting rearwardly from the rear seat 33 can be mounted on the backrest 135. In addition, since the backrest 135 is shaped to become gradually narrower in width towards the rear side in a top plan view, the backrest 135 can be made compact, the shape of the backrest 135 together with the shape of the vehicle body cover 34 provides a good harmony on a design basis, and dynamic performance can be more enhanced. Further, since the upper surface of a rear portion of the grab rail 118 is set at substantially the same height as the upper surface of the rear seat 33 and the backrest 135 is detachably attached to the upper surface of the rear portion of the grab rail 118, when it is desired to mount more luggage on the rear seat 33 it is possible to mount the luggage by effectively utilizing the upper surface of the rear portion of the grab rail 118 after the backrest 135 is detached. In addition, the oil supply lid 169 for closing the fuel tank 28 is disposed in the floor tunnel portion 167 of the vehicle body cover 34 and can be locked and is openably and closably attached to the floor tunnel portion 167 of the vehicle body cover 34 at a position corresponding to the fuel tank 28. In this case, the decorative cover 195 disposed at a position spaced from the oil supply lid 169 is openably and closably disposed on the inner cover 157 of the vehicle body cover 34, and the lock release operating member 272 for releasing the lock condition of the oil supply lid 169 is disposed on the inner cover 157 so as to be covered by the decorative cover 195 being in the closed condition. Therefore, the lock release operating member 272 is not be exposed as long as the decorative cover 195 is in the closed condition, whereby the possibility that the lock release operating member 272 might be trifled undesiredly can be minimized. Thus, the possibility of influences of disturbances such as weather on the lock release operating member 272 can be minimized. In addition, since the inner cover 157 constitutes a part of the vehicle body cover 34 while covering the head pipe 27 from the rear side and the decorative cover 195 and the lock release operating member 272 are disposed on the inner cover 157, the operations on the lock release operating member 272 can be facilitated by disposing the lock release operating member 272 at a position on the front side of and close to the rider. Further, since the decorative cover 195 is for covering the containing case 193 provided in the inner cover 157 from the vehicle body rear side and is not a member for exclusive use for covering the lock release operating member 272, the need for an exclusive-use member for covering the lock release operating member 272 can be eliminated. Thus, the number of component parts can be reduced. For example, when a wallet is put in the containing case 193, it is easy and convenient to pay the fuel charge at the time of supplying the fuel at a gas station, since the containing case 193 is opened whenever the oil supply lid 169 is opened. Moreover, the containing case 193 is provided in the inner cover 157 so as to be capable of being slid in the vehicle body front-rear direction between the fully closed position where it is contained in the inner cover 157 and the fully opened position where it projects from the inner cover 157. The lock release operating member 272 is disposed on the inner cover 157 at a position set off from the containing case 193 and at least partly overlapped with the head pipe as viewed from the rear side in the vehicle body front-rear direction. Thus, the decorative case 195 is attached to the containing case 193 so as to cover the lock release operating member 272 in the condition where the containing case 193 is in the fully closed position. Therefore, it is possible to dispose the lock release operating member 272 at a good spatial efficiency while securing the capacity of the containing case 193 by making the containing case 193 of the drawer type. In addition, since the left front containing portion 191 is provided with the case lock mechanism 208 for locking the containing case 193 in the fully closed position and it is necessary to release the lock condition of the containing case 193 in the fully closed position for opening the oil supply lid 169. Thus, the need for an exclusive-use lock mechanism for opening the oil supply lid 169 can be eliminated, and the locking structure can be simplified. Still further, since the left and right front containing portions 191 and 192 are provided in the inner cover 157 at an interval therebetween along the vehicle body width direction and the lock release operating member 272 is disposed between the left and right front containing portions 191 and 192, the arrangement of the lock release operating member 272 in the space generated between the left and right front containing portions 191 and 192 permits the lock release operating member 272 to be disposed at a good spatial efficiency. In addition, since the lock release operating member 272 is disposed at a position set off, for example to the left side, from the vehicle body center line C, the operations on the lock release operating member 272 can be facilitated by arranging the lock release operating member 272 at a position close to the left hand of the rider on the rider's seat 31. Moreover, the arrangement of the lock release operating member 272 as above is more effective, in relationship to the oil supply lid 169 covering the oil supply cap 168 which is used frequently. Further, in the left front containing portion 191, the holding mechanism 230 for temporarily holding the containing case 193 at an intermediate position between the fully closed position and the fully opened position when the containing case 193 is openingly operated from the fully closed position is provided between the containing case and the inner cover 157. Therefore, the containing case 193 can be temporarily held at the intermediate position between the fully closed position and the fully opened position, and the containing case 193 can be used in correspondence with various use conditions. Moreover, since the holding mechanism 230 is so configured that it can temporarily hold the containing case 193 at a roughly central position between the fully closed position and the fully opened position, things of appropriate sizes can be put into and taken out from the containing case 193 while holding the containing case 193 in the state of being opened to an appropriate extent. Further, the containing case 193 is mounted to the inner cover 157 so as to be capable of being slid in the vehicle body front-rear direction between the fully closed position where it is contained in the inner cover 157 and the fully opened position where it projects from the inner cover 157. The hold release operating member 237 for releasing the hold condition of the holding mechanism 230 is disposed on the lower surface of the containing case 193 at a position near the vehicle body center line C side and the vehicle body rear side. Therefore, the hold release operating member 237 can be disposed at such a position so as to be easy to operate in releasing the condition where the containing case 193 is temporarily held by the holding mechanism 230. In addition, the case lock mechanism 208 for locking the containing case 193 in the fully closed position according to a sliding operation of the containing case 193 towards the closing side to the fully closed position and for releasing the lock condition according to the action of an unlocking force is provided between the support frame 214 fixed to the inner cover 157 and the containing case 193. The containing case 193 present in the fully closed position is spring biased towards the opening side by the coil spring 212 and the spring means 222. Therefore, when an unlocking operation of the case lock mechanism 208 is effected by exerting an unlocking force, the containing case 193 is slid toward the opening side from the fully closed position by the spring biasing forces of the soil spring 212 and the spring means 222, and a part of the containing case 193 projecting from the inner cover 157. Thus, it is easy for the rider to visually confirm that the case lock mechanism 208 has been brought into the unlocked condition, and the containing case 193 can be drawn out with a small operating force. Further, the first and second lock release operating buttons 248a and 249a for respectively releasing the lock conditions of the left front containing portion 191 and the luggage box 30 are disposed on the inner cover 157 on a lateral side of the left front containing portion 191. Thus, the plurality of lock release operating buttons 248a, 249a are concentratedly disposed on the lateral side of the left front containing portion 191. Therefore, the operation of releasing the lock conditions of the left front containing portion 191 and the luggage box 30 are facilitated. In addition, since the first and second lock release operating buttons 248a, 249a are disposed at positions set off to the right side from the vehicle body center line C, the unlocking operations, the operations of releasing the lock conditions, by the rider on the rider's seat are further facilitated. Moreover, since the first and second lock release operating buttons 248a, 249a, formed to be horizontally elongated, are arranged in a vertically aligned pattern, the plurality of lock release operating buttons 248a, 249a can be arranged in a compact fashion such that the spaces in the vertical direction occupied by the lock release operating buttons 248a, 249a will not be large. Further, since the first lock release operating button 248a for releasing the lock condition of the left front containing portion 191, the case lock mechanism 208 possessed by the left front containing portion 191, and the first electric actuator 221 for exerting an unlocking force to the case lock mechanism 208 are disposed at substantially the same height, the wiring between the lock release operating button 248a for releasing the lock condition of the left front containing portion 191 and the first electric actuator 221 as well as the power transmission system between the first electric actuator 221 and the case lock mechanism 208 can be configured in a compact form. While one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various design modifications are possible without departure from the scope of the present invention as defined in the claims. For example, an embodiment of the present invention relating to the oil supply lid 169 has been described in the above. However, the present invention is also applicable in relation to the lid for covering the luggage box 30 on the lower side of the rider's seat 31, and is also applicable to a lid for maintenance of the vehicle body inside structure. Further, the lock release operating member 272 is not limited to an operating member for mechanically releasing the closed lock condition of a lid, but may be one for operating an electric actuator for releasing the lock condition, or may be one provided with an insertion hole for a key for releasing a lid lock mechanism. In addition, the present invention is also applicable to various vehicles such as motorcycle-type motorcycles, motor tricycles, buggy cars, etc. The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH> | <SOH> SUMMARY AND OBJECTS OF THE INVENTION <EOH>The present invention has been made in consideration of the above circumstances. It is an object of the invention to provide a lock release operator layout structure in a vehicle by which an operation for releasing the lock conditions of a plurality of containing portions is facilitated. In order to attain the above object, the present invention sets forth a lock release operator layout structure in a vehicle including containing portions which include a front containing portion provided in an inner cover covering from the rear side a head pipe of a vehicle body frame at its front end and constituting a part of a vehicle body cover and which can be locked in a fully closed condition wherein the lock release operators for releasing the lock conditions of the containing portions are disposed at the inner cover on a lateral side of the front containing portion. The lock release operators correspond to lock release operating buttons 248 a , 249 a in an embodiment of the present invention which will be described later. In addition, the present invention provides the lock release operators that are disposed at positions set off to either the left or right side from the vehicle body center line. The present invention includes a plurality of the lock release operators formed to be horizontally elongate that are arranged in a vertically aligned pattern. Further, the present invention provides the lock release operator for releasing the lock condition of the front containing portion, a case lock mechanism possessed by the front containing portion, and an electric actuator for exerting an unlocking force on the case lock mechanism that are disposed at substantially the same height. The present invention includes a plurality of the lock releasing operators that are arranged in a vertically aligned pattern. According to the present invention, since the plurality of lock release operators for respectively releasing the lock conditions of the plurality of containing portions inclusive of the front containing portion are concentratedly disposed on a lateral side of the front containing portion, the operation for releasing the lock conditions of the plurality of containing portions is facilitated. According to the present invention, the unlocking, lock releasing, operation by the rider on the rider's seat is further facilitated. According to the present invention, the plurality of lock release operators can be disposed in a compact form so that the space in the vertical direction occupied by the lock release operators will not be large. According to the present invention, the wiring between the lock release operator for releasing the lock condition of the front containing portion as well as the power transmission system between the electric actuator and the case lock mechanism can be configured in a compact form. According to the present invention, the plurality of lock release operators can be so arranged that the space in the horizontal direction occupied by the lock release operations is narrowed. In addition, the above-mentioned structure according to the related art has a problem in that the cover member can be located only in either one of the fully closed position and the full opened position. Therefore, the containing case cannot be used in correspondence with various use conditions. The present invention has been made in consideration of the foregoing circumstances. It is an object of the present invention to provide a containing structure for a vehicle which makes it possible for a containing case to be used in correspondence with various use conditions. In order attain the above object, the present invention resides in a containing structure for a vehicle, including an inner cover for covering from the rear side a head pipe of a vehicle body frame at its front end and which constitutes a part of a vehicle body cover. A containing case is mounted to the inner cover in an openable and closable condition. A holding mechanism for temporarily holding the containing case at an intermediate position between a fully closed position and a fully opened position of the containing case when the containing case is opened from the fully closed position is provided between the containing case and the inner cover so that its hold condition can be released. The present invention provides a holding mechanism that is capable of temporarily holding the containing case at a roughly central position between the fully closed position and the fully opened position. The present invention provides a containing case that is mounted to the inner cover so as to be slidable in the vehicle front-rear direction between the fully closed position where the containing case is contained in the inner cover and the fully opened position where the containing case projects from the inner cover. A hold release operating member for releasing the hold condition of the holding mechanism is disposed at a lower surface of the containing case at a position near the vehicle body center line side and the vehicle body rear side. The present invention includes a case lock mechanism for locking the containing case in the fully closed position according to the sliding of the containing case towards the closing side to the fully closed position and for releasing the lock condition according to the action of an unlocking force is provided between a support frame fixed to the inner cover and the containing case, and spring means for spring biasing the containing case in the fully closed position toward the opening side is provided. According to the present invention, it is possible for momentarily holding the containing case at an intermediate position between the fully closed position and the fully opened position. Therefore, the containing cases can be used in correspondence with various use conditions. According to the present invention, things appropriate in size can be put into and taken out of the containing case while holding the containing case in the state of being opened to an appropriate degree. According to the present invention, the hold release operating member can be arranged at such a position wherein it can be easily operated at the time of releasing the condition where the containing case is temporarily held by the holding mechanism. Furthermore, according to the present invention, when an unlocking force is exerted to put the case lock mechanism into an unlocking operation, the containing case is slid from the fully closed position towards the opening side by the spring biasing force of the spring means, so that a part of the containing case projects from the inner cover. Therefore, it can easily be confirmed visually by the rider that the case lock mechanism has been put into the unlock condition. Moreover, the containing case can be drawn out with a small operating force. Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. | 20050119 | 20070522 | 20050721 | 95799.0 | 0 | LYJAK, LORI LYNN | LOCK RELEASE OPERATOR LAYOUT STRUCTURE IN VEHICLE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,218 | ACCEPTED | Printing method, printing apparatus, and printing system | A printing method includes: printing, on a medium, a correction pattern made of lines, the lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction; measuring, for each line of the correction pattern, the darkness of pixels located on a same line of the correction pattern; obtaining, for each line of the correction pattern, a correction value for correcting a darkness, in the intersecting direction, of an image to be printed based on the darkness of the pixels that has been measured; setting, for each line of the image, the correction value obtained; and forming, in the dot forming operation, dots of a corresponding line for which the correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value. | 1. A printing method comprising the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, said plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying said medium in an intersecting direction that intersects said movement direction; measuring, for each line of said correction pattern, the darkness of a plurality of pixels located on a same line of said correction pattern; obtaining, for each line of said correction pattern, a correction value for correcting a darkness, in said intersecting direction, of an image to be printed based on the darkness of said plurality of pixels that has been measured; setting, for each line of said image, said correction value that has been obtained; and forming, in said dot forming operation, dots of a corresponding line for which said correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value. 2. A printing method according to claim 1, wherein there are provided a plurality of types of processing modes for executing print processing, in which at least one of said carrying operation and said dot forming operation is different from that in another print processing; and wherein in obtaining said correction value, at least two correction patterns each corresponding to a different one of said processing modes are each printed on said medium by the corresponding type of processing mode, of among the plurality of types of processing modes, and said correction value is obtained for each processing mode. 3. A printing method according to claim 1, wherein said correction value is obtained from an average value of the darkness of said plurality of pixels that has been measured. 4. A printing method according to claim 1, wherein an other correction value for correcting a darkness, in said movement direction, of said image is set for each pixel aligned in said movement direction; and wherein in said dot forming operation, dots of a corresponding line for which said correction value and said other correction value have been set are formed at a darkness that has been corrected based on said correction value and said other correction value. 5. A printing method according to claim 4, wherein said other correction value is obtained by: printing, on the medium, an other correction pattern; measuring the darkness of a plurality of pixels located at a same position, in said movement direction, of said other correction pattern; and obtaining said other correction value based on the darkness of said plurality of pixels that has been measured. 6. A printing method according to claim 5, wherein said other correction value is obtained from an average value of the darkness of said plurality of pixels that has been measured. 7. A printing method according to claim 4, wherein said other correction pattern is printed such that its darkness becomes the darkness corrected by said correction value, and said other correction value is obtained based on that other correction pattern. 8. A printing method according to claim 1, wherein said plurality of pixels whose darkness is to be measured are adjacent to one another. 9. A printing method according to claim 1, wherein said correction pattern has a plurality of types of patterns each having a different darkness. 10. A printing method according to claim 4, wherein said other correction pattern has a plurality of types of patterns each having a different darkness. 11. A printing method according to claim 1, wherein the darkness of said plurality of pixels is measured using a scanner device that is capable of reading an image that has been printed on said medium as data groups in units of pixels. 12. A printing method according to claim 11, wherein at least one of a movement-side reference ruled line extending in said movement direction and an intersecting-side reference ruled line extending in said intersecting direction is formed on said medium together with said correction pattern or said other correction pattern; wherein the data groups read by said scanner device are corrected based on said reference ruled line; and wherein the darkness of said plurality of pixels is measured for said data groups that have been corrected. 13. A printing method according to claim 1, wherein a plurality of said nozzles constitute a nozzle row aligned in said intersecting direction. 14. A printing method according to claim 13, wherein said nozzle row is provided for each color of said ink; wherein, by printing at least one of said correction pattern and said other correction pattern for each said color, at least one of said correction value and said other correction value is provided for each said color; and wherein the darkness of the image is corrected for each color based on at least one of the correction value and the other correction value for that color. 15. A printing method according to claim 13, wherein a line that is not formed is set between said lines that are formed in a single said dot forming operation; and wherein the lines are formed in a complementary manner through a plurality of the dot forming operations. 16. A printing method according to claim 2, wherein the print processing being different in said carrying operation is print processing in which a pattern of change in a carry amount of each said carrying operation is different from that in another print processing; and wherein the print processing being different in said dot forming operation is print processing in which a pattern of change in the nozzles that are used in each said dot forming operation is different from that in another print processing. 17. A printing method comprising the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, said plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying said medium in an intersecting direction that intersects said movement direction; measuring, for each line of said correction pattern, the darkness of a plurality of pixels located on a same line of said correction pattern; obtaining, for each line of said correction pattern, a correction value for correcting a darkness, in said intersecting direction, of an image to be printed based on the darkness of said plurality of pixels that has been measured; setting, for each line of said image, said correction value that has been obtained; and forming, in said dot forming operation, dots of a corresponding line for which said correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value; wherein there are provided a plurality of types of processing modes for executing print processing, in which at least one of said carrying operation and said dot forming operation is different from that in another print processing; wherein in obtaining said correction value, at least two correction patterns each corresponding to a different one of said processing modes are each printed on said medium by the corresponding type of processing mode, of among the plurality of types of processing modes, and said correction value is obtained for each processing mode; wherein said correction value is obtained from an average value of the darkness of said plurality of pixels that has been measured; wherein an other correction value for correcting a darkness, in said movement direction, of said image is set for each pixel aligned in said movement direction; wherein in said dot forming operation, dots of a corresponding line for which said correction value and said other correction value have been set are formed at a darkness that has been corrected based on said correction value and said other correction value; wherein said other correction value is obtained by: printing, on the medium, an other correction pattern; measuring the darkness of a plurality of pixels located at a same position, in said movement direction, of said other correction pattern; and obtaining said other correction value based on the darkness of said plurality of pixels that has been measured; wherein said other correction value is obtained from an average value of the darkness of said plurality of pixels that has been measured; wherein said other correction pattern is printed such that its darkness becomes the darkness corrected by said correction value, and said other correction value is obtained based on that other correction pattern; wherein said plurality of pixels whose darkness is to be measured are adjacent to one another; wherein said correction pattern has a plurality of types of patterns each having a different darkness; wherein said other correction pattern has a plurality of types of patterns each having a different darkness; wherein the darkness of said plurality of pixels is measured using a scanner device that is capable of reading an image that has been printed on said medium as data groups in units of pixels; wherein at least one of a movement-side reference ruled line extending in said movement direction and an intersecting-side reference ruled line extending in said intersecting direction is formed on said medium together with said correction pattern or said other correction pattern; wherein the data groups read by said scanner device are corrected based on said reference ruled line; wherein the darkness of said plurality of pixels is measured for said data groups that have been corrected; wherein a plurality of said nozzles constitute a nozzle row aligned in said intersecting direction; wherein said nozzle row is provided for each color of said ink; wherein, by printing at least one of said correction pattern and said other correction pattern for each said color, at least one of said correction value and said other correction value is provided for each said color; wherein the darkness of the image is corrected for each color based on at least one of the correction value and the other correction value for that color; wherein a line that is not formed is set between said lines that are formed in a single said dot forming operation; wherein the lines are formed in a complementary manner through a plurality of the dot forming operations; wherein the print processing being different in said carrying operation is print processing in which a pattern of change in a carry amount of each said carrying operation is different from that in another print processing; and wherein the print processing being different in said dot forming operation is print processing in which a pattern of change in the nozzles that are used in each said dot forming operation is different from that in another print processing. 18. A printing apparatus comprising: nozzles for ejecting ink; and a carrying unit for carrying a medium; wherein by repeating in alternation a dot forming operation of forming dots on said medium by ejecting ink from a plurality of said nozzles that move in a predetermined movement direction, and a carrying operation of carrying said medium in an intersecting direction that intersects said movement direction using said carrying unit, said printing apparatus forms, in said intersecting direction, a plurality of lines each made of a plurality of dots aligned in said movement direction to print an image; wherein a correction value for correcting a darkness, in said intersecting direction, of said image is set for each line; wherein in said dot forming operation, dots of a corresponding line for which said correction value has been set are formed such that the darkness of that line becomes a darkness that has been corrected based on said correction value; and wherein said correction value is obtained by: printing, on the medium, a correction pattern that is made of a plurality of the lines; measuring, for each line of said correction pattern, the darkness of a plurality of pixels located on a same line of said correction pattern; and obtaining, for each line of said correction pattern, said correction value based on the darkness of said plurality of pixels that has been measured. 19. A printing system comprising: a computer; and a printing apparatus that is communicably connected to said computer, and that is provided with nozzles for ejecting ink and a carrying unit for carrying a medium; wherein by repeating in alternation a dot forming operation of forming dots on said medium by ejecting ink from a plurality of said nozzles that move in a predetermined movement direction, and a carrying operation of carrying said medium in an intersecting direction that intersects said movement direction using said carrying unit, said printing system forms, in said intersecting direction, a plurality of lines each made of a plurality of dots aligned in said movement direction to print an image; wherein a correction value for correcting a darkness, in said intersecting direction, of said image is set for each line; wherein in said dot forming operation, dots of a corresponding line for which said correction value has been set are formed such that the darkness of that line becomes a darkness that has been corrected based on said correction value; and wherein said correction value is obtained by: printing, on the medium, a correction pattern that is made of a plurality of the lines; measuring, for each line of said correction pattern, the darkness of a plurality of pixels located on a same line of said correction pattern; and obtaining, for each line of said correction pattern, said correction value based on the darkness of said plurality of pixels that has been measured. | CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority upon Japanese Patent Application No. 2004-13607 filed on Jan. 21, 2004, which is herein incorporated by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to printing methods, printing apparatuses, and printing systems. 2. Description of the Related Art Inkjet printers (hereinafter referred to simply as “printers”) that eject ink onto a medium such as paper to form dots are known as printing apparatuses for printing images. These printers repeat in alternation a dot forming operation of forming dots on a paper by ejecting ink from a plurality of nozzles, which move in the movement direction of a carriage, and a carrying operation of carrying, using a carrying unit, the paper in an intersecting direction (hereinafter, also referred to as the “carrying direction”) that intersects the movement direction. By doing this, a plurality of raster lines made of a plurality of dots in the movement direction are formed in the intersecting direction, thereby printing an image. With this type of printer, there are discrepancies in the ink droplet ejection characteristics, such as the quantity of the ink droplet and the travel direction, among the nozzles. Discrepancies in the ejection characteristics are a cause of darkness nonuniformities in printed images, and thus are not preferable. Accordingly, a conventional method involves setting a correction value for each nozzle and adjusting the quantity of ink based on those correction values that are set. (See, for example, JP H06-166247A (pg. 4, 7, and 8).) With this conventional method, first, correction patterns are printed on the paper. Printing of these correction patterns is performed by moving a head, which is provided with the nozzles, in a scanning direction while intermittently ejecting ink from all of the nozzles. Then, the darkness of the correction patterns that are printed is measured for each pixel. This darkness measurement is performed in the carrying direction for one spot in the scanning direction of the correction patterns. However, with this conventional method, there is a possibility that the darkness that is obtained will change depending on the measurement position, even when measuring the same pixel. This is due to the fact that the dots that are formed are circular. In other words, with this type of printer, the dots that land on the paper spread out in a circular manner. The darkness thus differs between a case where the darkness is measured along a straight line that passes over the center of the dot and a case where the darkness is measured along a straight line that passes over the edge of the dot. That is, the darkness of the latter will be lower than the darkness of the former. Therefore, it is difficult to obtain an accurate darkness by measuring only one spot in the main-scanning direction. Further, with this method there is also a possibility that the quality of the printed image will drop if interlacing is adopted as the print mode. Interlacing is a print mode in which a raster line that is not formed is set between raster lines that are formed in a single dot forming operation, and through a plurality of dot forming operations all of the raster lines are formed in a complementary manner, and with this print mode, adjacent raster lines are not printed by the same nozzle. Also, with interlacing, the nozzle that forms an adjacent raster line will not always be the adjacent nozzle. That is to say, it is possible for the combination of nozzles that form adjacent raster lines in the printed image to be different from the combination in the correction patterns. Here, darkness nonuniformities caused by bending in the flight path of the ink occur due to the spacing between adjacent raster lines becoming small or large, and also occur due to the combination of the nozzles forming the adjacent raster lines. Therefore, it is difficult to correct darkness nonuniformities that result from the combination of raster lines and nozzles using a correction pattern that is printed by ejecting ink from all of the nozzles. SUMMARY OF THE INVENTION The present invention was arrived at in light of the foregoing issues, and it is an object thereof to achieve a printing method, a printing apparatus, and a printing system with which darkness nonuniformities can be effectively inhibited. An aspect of the present invention is a printing method comprising the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, the plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; obtaining, for each line of the correction pattern, a correction value for correcting a darkness, in the intersecting direction, of an image to be printed based on the darkness of the plurality of pixels that has been measured; setting, for each line of the image, the correction value that has been obtained; and forming, in the dot forming operation, dots of a corresponding line for which the correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value. Other features of the present invention will become clear through the accompanying drawings and the following description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of an overall configuration of a printing system; FIG. 2 is an explanatory diagram of the processing performed by the printer driver; FIG. 3 is a flowchart of halftone processing according to dithering; FIG. 4 is a diagram showing a dot creation ratio table; FIG. 5 is a diagram showing how dots are determined to be on or off according to dithering; FIG. 6A is a dither matrix used in determining large dots, and FIG. 6B is a dither matrix used in determined medium dots; FIG. 7 is an explanatory diagram of the user interface of the printer driver; FIG. 8 is a block diagram of the overall configuration of the printer; FIG. 9 is a schematic diagram of the overall configuration of the printer; FIG. 10 is a horizontal cross-section of the overall configuration of the printer; FIG. 11 is an explanatory diagram showing the arrangement of the nozzles; FIG. 12 is an explanatory diagram of the drive circuit of the head unit; FIG. 13 is a timing chart for describing the various signals; FIG. 14 is a flowchart of the operations during printing; FIG. 15A and FIG. 15B are explanatory diagrams of interlacing; FIG. 16 is a diagram showing the size relationship between the print region and the paper during bordered printing; FIG. 17 is a diagram showing the size relationship between the print region and the paper during borderless printing; FIG. 18A to FIG. 18C are diagrams showing the positional relationship between the grooves provided in the platen and the nozzles; FIG. 19 is a first reference table showing the print modes corresponding to the various combinations between the margin format mode and the image quality mode; FIG. 20 is a second reference table showing the processing modes corresponding to the various print modes.; FIG. 21A is a diagram for describing the various processing modes, and FIG. 21B is a diagram for describing the various processing modes; FIG. 22A is a diagram for describing the various processing modes, and FIG. 22B is a diagram for describing the various processing modes; FIG. 23A is a diagram for describing the various processing modes, and FIG. 23B is a diagram for describing the various processing modes; FIG. 24A is a diagram for describing the various processing modes, and FIG. 24B is a diagram for describing the various processing modes; FIG. 25A is a diagram for describing the darkness nonuniformities that occur, in an image printed in a single color, in the carrying direction of the paper, and FIG. 25B is a diagram for describing the darkness nonuniformities that occur in the carriage movement direction; FIG. 26 is a diagram schematically showing the relationship between the nozzles and the correction patterns printed according to a method of a reference example; FIG. 27A is a diagram schematically showing the measurement positions of the dots, and FIG. 27B is a diagram showing the measurement signal that is obtained by measuring the measurement position of FIG. 27A; FIG. 28A is a diagram describing how the darkness of a halftone correction pattern is measured, and FIG. 28B is a diagram describing the detection signals that are obtained through the darkness measurement of FIG. 28A; FIG. 29 is a flowchart showing the flow of the processing related to the method for printing the image; FIG. 30 is a block diagram describing equipments used for setting the correction values; FIG. 31 is a conceptual diagram of a recording table; FIG. 32 is a conceptual diagram of the correction value storage section; FIG. 33A is a vertical cross-section of the scanner device, and FIG. 33B is a plan view of that scanner device; FIG. 34 is a flowchart showing the procedure of step S120 in FIG. 29; FIG. 35 is a diagram describing an example of the correction pattern that is printed; FIG. 36 is a diagram describing how the correction pattern is read by the line sensor; FIG. 37A is a diagram schematically describing the positions where the dots are read by the light-receiving elements provided in the line sensor, FIG. 37B is a diagram describing the detection signals in the case of reading at the positions of FIG. 37A, and FIG. 37C is a diagram describing the difference in the recognized pixel darkness from the pulses of FIG. 37B; FIG. 38 is a diagram describing the darkness of the pixels read by the scanner device; FIG. 39 is a flowchart showing the specific procedure of the step S123 in FIG. 34; FIG. 40 is a diagram schematically describing the tilt correction that is performed in step S123a; FIG. 41A is a diagram showing the results of measuring the darkness of specific pixels along a line parallel to the carrying direction and at the same position in the carriage movement direction, and FIG. 41B is a diagram showing the measurement results obtained by changing the position of this line, and the average darkness that is obtained from these measurement results; FIG. 42 is a flowchart showing the specific procedure of step S124 in FIG. 34; FIG. 43 is a graph for describing primary interpolation, which is performed using three information pairs; FIG. 44 is a flowchart showing the specific procedure of step S140 in FIG. 29; FIG. 45 is a diagram that schematically shows the pixels that are formed on the paper; FIG. 46 is a conceptual diagram of the recording table that is used for obtaining the other correction values; FIG. 47 is a conceptual diagram of the correction value storage section, and shows a correction value table for storing the other correction values; FIG. 48 is a flowchart showing the specific procedure of step S120 in FIG. 29; FIG. 49 is a diagram describing an example of the other correction pattern CP; FIG. 50 is a diagram for describing the darkness of the pixels that is read by the scanner device; FIG. 51 is a flowchart showing the specific procedure of step S127 in FIG. 48; and FIG. 52 is a flowchart showing the specific procedure of step S128 in FIG. 48. DETAILED DESCRIPTION OF THE INVENTION At least the following matters will become clear by the explanation in the present specification and the description of the accompanying drawings. A printing method comprises the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, the plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; obtaining, for each line of the correction pattern, a correction value for correcting a darkness, in the intersecting direction, of an image to be printed based on the darkness of the plurality of pixels that has been measured; setting, for each line of the image, the correction value that has been obtained; and forming, in the dot forming operation, dots of a corresponding line for which the correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value. According to this printing method, the darkness of a plurality of pixels located on the same line of a correction pattern is measured, and a correction value is obtained based on the darkness of the pixels that is measured, the correction value is set for each line, and the dots of a corresponding line are formed such that the darkness becomes a darkness after correction based on this correction value. Therefore, darkness irregularities caused by differences in the measurement positions of the dots can be cancelled out. Thus, darkness nonuniformities in the image can be effectively inhibited. Further, it is preferable that there are provided a plurality of types of processing modes for executing print processing, in which at least one of the carrying operation and the dot forming operation is different from that in another print processing; and that in obtaining the correction value, at least two correction patterns each corresponding to a different one of the processing modes are each printed on the medium by the corresponding type of processing mode, of among the plurality of types of processing modes, and the correction value is obtained for each processing mode. According to this printing method, there is a darkness correction value for each line for at least two types of processing modes. Further, when printing an image using either one of the at least two types of processing modes, the darkness of the lines is corrected based on the correction value corresponding to that line of the image. Consequently, regardless of the processing mode that is used to print the image, the most appropriate correction value for that mode can be adopted for the lines of the image. Thus, darkness irregularities between lines can be effectively reduced, allowing darkness nonuniformities to be effectively inhibited. Further, it is preferable that the correction value is obtained from an average value of the darkness of the plurality of pixels that has been measured. According to this printing method, the correction value is obtained from an average value of the darkness of a plurality of pixels that has been measured, and thus darkness irregularities caused by differences in the measurement position of the dots can be cancelled out at a higher level, allowing darkness nonuniformities in the image to be effectively inhibited. Further, it is preferable that an other correction value for correcting a darkness, in the movement direction, of the image is set for each pixel aligned in the movement direction; and that in the dot forming operation, dots of a corresponding line for which the correction value and the other correction value have been set are formed at a darkness that has been corrected based on the correction value and the other correction value. According to this printing method, the darkness is corrected also taking into account an other correction value that is set for each pixel lined up in the movement direction, and thus the darkness of the entire line can be corrected by the correction value, and the darkness of each of the dots making up that line is corrected by the other correction value. As a result, darkness nonuniformities in the movement direction as well can be inhibited, allowing darkness nonuniformities in the image to be effectively inhibited. Further, it is preferable that the other correction value is obtained by: printing, on the medium, an other correction pattern; measuring the darkness of a plurality of pixels located at a same position, in the movement direction, of the other correction pattern; and obtaining the other correction value based on the darkness of the plurality of pixels that has been measured. According to this printing method, the other correction values are obtained based on the darkness of a plurality of pixels located at the same position in the movement direction, and the dots of the corresponding line are formed such that their darkness becomes the darkness after correction based on the correction value. Therefore, for darkness nonuniformities in the movement direction as well, the darkness irregularities caused by differences in the measurement position of the dots can be cancelled out. Thus, darkness nonuniformities in the image can be effectively inhibited. Further, it is preferable that the other correction value is obtained from an average value of the darkness of the plurality of pixels that has been measured. According to this printing method, the other correction value is obtained from an average value of the darkness of the plurality of pixels that is measured, and thus darkness irregularities caused by differences in the measurement position of the dots can be cancelled out. As a result, darkness nonuniformities in the image can be more effectively inhibited. Further, it is preferable that the other correction pattern is printed such that its darkness becomes the darkness corrected by the correction value, and the other correction value is obtained based on that other correction pattern. According to this printing method, the other correction pattern is printed in such a manner that its darkness becomes the darkness corrected by the correction value, thereby correcting darkness nonuniformities in the intersecting direction. Then, the pixel darkness of this other correction pattern in which darkness nonuniformities in the intersecting direction have been corrected is measured to obtain the other correction values, and thus irregularities in the darkness of the measured pixels can be suppressed. As a result, the reliability of the other correction values can be increased. Further, it is preferable that the plurality of pixels whose darkness is to be measured are adjacent to one another. According to this printing method, the problem of selectively measuring only spots where darkness nonuniformities have occurred, in a case where darkness nonuniformities appear in a periodic manner, can be reliably prevented. As a result, the reliability of the correction values and the other correction values can be increased. Further, it is preferable that the correction pattern has a plurality of types of patterns each having a different darkness. According to this printing method, the correction value of a target line is obtained based on the pixel darkness found using a plurality of types of patterns having different darkness, and thus the correction value can be found by performing processing such as primary interpolation with respect to the data obtained at the various darkness. As a result, the correction values can be obtained efficiently. Further, it is preferable that the other correction pattern has a plurality of types of patterns each having a different darkness. According to this printing method, the other correction value of a target pixel is obtained based on the pixel darkness found using a plurality of types of patterns having different darkness, and thus the other correction value can be found by performing processing such as primary interpolation with respect to the data obtained at the various darkness. As a result, the other correction value can be obtained efficiently. Further, it is preferable that the darkness of the plurality of pixels is measured using a scanner device that is capable of reading an image that has been printed on the medium as data groups in units of pixels. According to this printing method, data groups corresponding to the correction patterns or the other correction patterns can be handled together, allowing increased processing efficiency to be attained. Further, it is preferable that at least one of a movement-side reference ruled line extending in the movement direction and an intersecting-side reference ruled line extending in the intersecting direction is formed on the medium together with the correction pattern or the other correction pattern; that the data groups read by the scanner device are corrected based on the reference ruled line; and that the darkness of the plurality of pixels is measured for the data groups that have been corrected. According to this printing method, even if, when reading a correction pattern or an other correction pattern with the scanner device, that pattern is read shifted from the normal position, this shifting can be corrected using the movement-side reference ruled line or the intersecting-side reference ruled line. Further, because the pixel darkness is measured after this shifting has been corrected, the reliability of the correction value or the other correction value can be increased. Further, this shifting of the pattern can be automatically corrected through image processing. Thus, an increase in processing efficiency can be attained. Further, it is preferable that a plurality of the nozzles constitute a nozzle row aligned in the intersecting direction. According to this printing method, the nozzles are arranged in rows in the intersecting direction, thus widening the range over which dots are formed in a single dot forming operation and allowing the printing time to be shortened. Further, it is preferable that the nozzle row is provided for each color of the ink; that by printing at least one of the correction pattern and the other correction pattern for each color, at least one of the correction value and the other correction value is provided for each color; and that the darkness of the image is corrected for each color based on at least one of the correction value and the other correction value for that color. According to this printing method, a nozzle row is provided for each ink color, and thus multicolor printing can be performed. Further, because the darkness of the image is corrected for each color based on the correction values and the other correction values for each color, it is possible to effectively inhibit darkness nonuniformities in the image during multicolor printing. Further, it is preferable that a line that is not formed is set between the lines that are formed in a single dot forming operation; and that the lines are formed in a complementary manner through a plurality of the dot forming operations. According to this printing method, darkness nonuniformities in the image can be effectively inhibited even in a case where the relationship between the nozzles responsible for adjacent lines does not match the order in which the nozzles constituting the nozzle rows are arranged. Further, it is preferable that the print processing being different in the carrying operation is print processing in which a pattern of change in a carry amount of each carrying operation is different from that in another print processing; and that the print processing being different in the dot forming operation is print processing in which a pattern of change in the nozzles that are used in each dot forming operation is different from that in another print processing. According to this printing method, because the processing modes are different for each pattern of change in the carry amount, a correction pattern is printed for each change pattern and each change pattern is provided with a correction value. Consequently, it is possible to respond to a change in the combination of nozzles forming adjacent lines, which changes for each change pattern. As a result, each line can be corrected by the most suitable correction value. Further, because the processing modes are different for each pattern of change in the nozzles that are used, a correction pattern is printed for each change pattern and each change pattern is provided with a correction value. Consequently, it is possible to respond to a change in the combination of nozzles forming adjacent lines, which changes for each change pattern. As a result, each line can be corrected by the most suitable correction value. It is also possible to achieve a printing method comprising the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, the plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; obtaining, for each line of the correction pattern, a correction value for correcting a darkness, in the intersecting direction, of an image to be printed based on the darkness of the plurality of pixels that has been measured; setting, for each line of the image, the correction value that has been obtained; and forming, in the dot forming operation, dots of a corresponding line for which the correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value; wherein there are provided a plurality of types of processing modes for executing print processing, in which at least one of the carrying operation and the dot forming operation is different from that in another print processing; wherein in obtaining the correction value, at least two correction patterns each corresponding to a different one of the processing modes are each printed on the medium by the corresponding type of processing mode, of among the plurality of types of processing modes, and the correction value is obtained for each processing mode; wherein the correction value is obtained from an average value of the darkness of the plurality of pixels that has been measured; wherein an other correction value for correcting a darkness, in the movement direction, of the image is set for each pixel aligned in the movement direction; wherein in the dot forming operation, dots of a corresponding line for which the correction value and the other correction value have been set are formed at a darkness that has been corrected based on the correction value and the other correction value; wherein the other correction value is obtained by: printing, on the medium, an other correction pattern; measuring the darkness of a plurality of pixels located at a same position, in the movement direction, of the other correction pattern; and obtaining the other correction value based on the darkness of the plurality of pixels that has been measured; wherein the other correction value is obtained from an average value of the darkness of the plurality of pixels that has been measured; wherein the other correction pattern is printed such that its darkness becomes the darkness corrected by the correction value, and the other correction value is obtained based on that other correction pattern; wherein the plurality of pixels whose darkness is to be measured are adjacent to one another; wherein the correction pattern has a plurality of types of patterns each having a different darkness; wherein the other correction pattern has a plurality of types of patterns each having a different darkness; wherein the darkness of the plurality of pixels is measured using a scanner device that is capable of reading an image that has been printed on the medium as data groups in units of pixels; wherein at least one of a movement-side reference ruled line extending in the movement direction and an intersecting-side reference ruled line extending in the intersecting direction is formed on the medium together with the correction pattern or the other correction pattern; wherein the data groups read by the scanner device are corrected based on the reference ruled line; wherein the darkness of the plurality of pixels is measured for the data groups that have been corrected; wherein a plurality of the nozzles constitute a nozzle row aligned in the intersecting direction; wherein the nozzle row is provided for each color of the ink; wherein, by printing at least one of the correction pattern and the other correction pattern for each color, at least one of the correction value and the other correction value is provided for each color; wherein the darkness of the image is corrected for each color based on at least one of the correction value and the other correction value for that color; wherein a line that is not formed is set between the lines that are formed in a single dot forming operation; wherein the lines are formed in a complementary manner through a plurality of the dot forming operations; wherein the print processing being different in the carrying operation is print processing in which a pattern of change in a carry amount of each carrying operation is different from that in another print processing; and wherein the print processing being different in the dot forming operation is print processing in which a pattern of change in the nozzles that are used in each dot forming operation is different from that in another print processing. With this printing method, substantially all of the effects mentioned above are attained, and thus the object of the present invention is more effectively achieved. It is also possible to achieve a printing apparatus comprising: nozzles for ejecting ink; and a carrying unit for carrying a medium; wherein by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of the nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction using the carrying unit, the printing apparatus forms, in the intersecting direction, a plurality of lines each made of a plurality of dots aligned in the movement direction to print an image; wherein a correction value for correcting a darkness, in the intersecting direction, of the image is set for each line; wherein in the dot forming operation, dots of a corresponding line for which the correction value has been set are formed such that the darkness of that line becomes a darkness that has been corrected based on the correction value; and wherein the correction value is obtained by: printing, on the medium, a correction pattern that is made of a plurality of the lines; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; and obtaining, for each line of the correction pattern, the correction value based on the darkness of the plurality of pixels that has been measured. It is also possible to achieve a printing system comprising: a computer; and a printing apparatus that is communicably connected to the computer, and that is provided with nozzles for ejecting ink and a carrying unit for carrying a medium; wherein by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of the nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction using the carrying unit, the printing system forms, in the intersecting direction, a plurality of lines each made of a plurality of dots aligned in the movement direction to print an image; wherein a correction value for correcting a darkness, in the intersecting direction, of the image is set for each line; wherein in the dot forming operation, dots of a corresponding line for which the correction value has been set are formed such that the darkness of that line becomes a darkness that has been corrected based on the correction value; and wherein the correction value is obtained by: printing, on the medium, a correction pattern that is made of a plurality of the lines; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; and obtaining, for each line of the correction pattern, the correction value based on the darkness of the plurality of pixels that has been measured. ===Configuration of the Printing System=== An embodiment of a printing system is described next with reference to the drawings. FIG. 1 is an explanatory diagram showing the external structure of the printing system. This printing system is provided with an inkjet printer 1 (hereinafter, referred to simply as “printer 1”), a computer 1100, a display device 1200, an input device 1300, and a record/play device 1400. The printer 1 is a printing apparatus for printing images on a medium such as paper, cloth, or film. It should be noted that the following description is made using paper S (see FIG. 9), which is a representative medium, as an example of the medium. The computer 1100 is communicably connected to the printer 1, and outputs print data corresponding to an image to be printed to the printer 1 in order to print the image with the printer 1. The display device 1200 has a display, and displays a user interface such as an application program or a printer driver 1110 (see FIG. 2). The input device 1300 is for example a keyboard 1300A and a mouse 1300B, and is used to operate the application program or adjust the settings of the printer driver 1110, for example, through the user interface that is displayed on the display device 1200. A flexible disk drive device 1400A and a CD-ROM drive device 1400B, for example, are employed as the record/play device 1400. The printer driver 1110 is installed on the computer 1100. The printer driver 1110 is a program for achieving the function of displaying the user interface on the display device 1200, and in addition it also achieves the function of converting image data that have been output from the application program into print data. The printer driver 1110 is recorded on a storage medium (computer-readable storage medium) such as a flexible disk FD or a CD-ROM. Further, the printer driver 1110 can be downloaded onto the computer 1100 via the Internet. This program is made of codes for achieving various functions. It should be noted that “printing apparatus” in a narrow sense means the printer 1, but in a broader sense it means the system constituted by the printer 1 and the computer 1100. ===Printer Driver=== <Regarding the Printer Driver> FIG. 2 is a schematic explanatory diagram of the basic processes carried out by the printer driver 1110. It should be noted that structural elements that have already been described are assigned identical reference numerals and thus further description thereof is omitted. On the computer 1100, computer programs such as a video driver 1102, an application program 1104, and the printer driver 1110 operate under an operating system installed on the computer 1100. The video driver 1102 has a function of displaying, for example, the user interface on the display device 1200 in accordance with display commands from the application program 1104 and the printer driver 1110. The application program 1104 has, for example, the function of performing image editing, and creates data (image data) related to an image. A user can give an instruction to print an image edited by the application program 1104 via the user interface of the application program 1104. Upon receiving the print instruction, the application program 1104 outputs image data to the printer driver 1110. The printer driver 1110 receives the image data from the application program 1104, converts the image data into print data, and outputs the print data to the printer 1. The image data have pixel data as the data on the pixels of the image to be printed. The gradation values, for example, of the pixel data are then converted in accordance with the processing stage, which are described later, and ultimately, at the print data stage are converted into data on the dots to be formed on the paper (data such as the color and the size of the dots). It should be noted that “pixels” are the virtually determined square grids on the paper for defining the positions onto which ink lands to form dots. In other words, the pixels are regions on the paper on which dots can be formed, and can be thought of as “dot formation units.” Print data are data in a format that can be interpreted by the printer 1, and include various command data and pixel data. Here, “command data” refers to data for instructing the printer 1 to carry out a specific operation, and are data indicating the carry amount, for example. In order to convert the image data that are output from the application program 1104 into print data, the printer driver 1110 carries out processes such as resolution conversion, color conversion, halftone processing, and rasterization. The various processes carried out by the printer driver 1110 are described below. Resolution conversion is a process for converting image data (text data, image data, etc.) output from the application program 1104 to a resolution (the spacing between dots when printing; also referred to as “print resolution”) for when printing an image on the paper S. For example, when the print resolution is designated as 720±720 dpi, then the image data obtained from the application program 1104 are converted into image data having a resolution of 720±720 dpi. Pixel data interpolation and thinning-out are examples of this conversion method. For example, if the resolution of the image data is lower than the print resolution that has been designated, then linear interpolation or the like is performed to create new pixel data between adjacent pixel data. On the other hand, if the resolution of the image data is higher than the print resolution, then the pixel data are thinned out, for example, at a set ratio to make the image-data resolution match the print resolution. Further, in this resolution conversion processing, the size of the “print region” (which is the region to which ink is actually ejected) is adjusted based on the image data. This size adjustment is performed by trimming, for example, the pixel data that correspond to the ends of the paper S of the image data, in accordance with the margin format mode, the image quality mode, and the paper size mode, which are described later. It should be noted that the pixel data of the image data have a gradation value of many gradations (for example, 256 gradations) expressed by the RGB color space. The pixel data having this RGB gradation value are hereinafter referred to as “RGB pixel data,” and the image data made of these RGB pixel data are referred to as “RGB image data.” Color conversion processing is for converting each piece of RGB pixel data of the RGB image data into data having a gradation value of many gradations (for example, 256) expressed by the CMYK color space. CMYK are the ink colors of the printer 1. That is, C stands for cyan. Further, M stands for magenta, Y for yellow, and K for black. Hereinafter, the pixel data having CMYK gradation values are referred to as “CMYK pixel data”, and the image data made of these CMYK pixel data are referred to as “CMYK image data”. Color conversion processing is carried out by the printer driver 1110, with reference to a table (color conversion lookup table LUT) that correlates RGB gradation values and CMYK gradation values. Halftone processing is for converting CMYK pixel data having many gradation values into CMYK pixel data having fewer gradation values that can be expressed by the printer 1. For example, through halftone processing, CMYK pixel data having a gradation value of 256 gradations are converted into 2-bit CMYK pixel data having a gradation value of four gradations. For example, the 2-bit CMYK pixel data indicate, for each color, “no dot formation” (binary value “00”), “small dot formation” (binary value “01”), “medium dot formation” (binary value “10”), and “large dot formation” (binary value “11”). Dithering or the like is used for halftone processing to create 2-bit CMYK pixel data with which the printer 1 can form dispersed dots. It should be noted that halftone processing according to dithering is described later. Further, the method used for halftone processing is not limited to dithering, and it is also possible to use γ-correction or error diffusion. It should be noted that in halftone processing in this embodiment, darkness correction based on the correction value or on the other correction value is performed. Darkness correction will be described in detail later. Rasterization is for changing the CMYK pixel data that have been subjected to halftone processing into the data order in which they are to be transferred to the printer 1. Data that have been rasterized are output to the printer 1 as print data. <Halftone Processing According to Dithering> Here, halftone processing according to dithering is described. FIG. 3 is a flowchart of halftone processing according to dithering. The printer driver 1110 performs the following steps in accordance with this flowchart. First, in step S300, the printer driver 1110 obtains the CMYK image data. The CMYK image data are made of image data expressed by gradation values of 256 gradations for each ink color C, M, Y, and K. In other words, the CMYK image data include C image data for cyan (C), M image data for magenta (M), Y image data for yellow (Y), and K image data for black (K). These C, M, Y, and K image data are respectively made of C, M, Y, and K pixel data indicating the gradation values of that ink color. It should be noted that the following description can be applied to any of the C, M, Y, and K image data, and therefore, the K image data are described as a representative. The printer driver 1110 performs the processing of the steps S301 to S311 for all of the K pixel data of the K image data while successively changing the K pixel data to be processed. Through this processing, the K image data are converted into 2-bit data having a gradation value of the four gradations mentioned above for each K pixel data. This conversion processing is described in detail here. First, in step S301, the large dot level LVL is set in accordance with the gradation value of the K pixel data to be processed. This setting is performed through the following procedure, using for example a creation ratio table. FIG. 4 is a diagram showing a creation ratio table that is used for setting the level data for each of the large, medium, and small dots. In this diagram, the horizontal axis indicates gradation values (0-255), the vertical axis on the left is the dot creation ratio (%), and the vertical axis on right is the level data (0-255). Here, the level data refers to data whose dot creation ratio has been converted to one of 256 gradation values from 0 to 255. Further, the “dot creation ratio” is used to mean the proportion of pixels at which dots are formed among the pixels that exist within a uniform region reproduced according to a constant gradation value. For example, take a case where the dot creation ratio for a particular gradation value is large dot 65%, medium dot 25%, and small dot 10%, and at this dot creation ratio, a region of 100 pixels made of 10 pixels in the vertical direction by 10 pixels in the horizontal direction is printed. In this case, of the 100 pixels, 65 of the pixels will be formed by large dots, 25 of the pixels will be formed by medium dots, and 10 of the pixels will be formed by small dots. The profile SD shown by the thin solid line in FIG. 4 indicates the dot creation ratio of the small dots. Further, the profile MD shown by the thick solid line indicates the dot creation ratio of the medium dots, and the profile LD shown by the dotted line indicates the creation ratio of the large dots. Consequently, in step S301, the level data LVL corresponding to the gradation value are read from the profile LD for large dots. For example, as shown in FIG. 4, if the gradation value of the K pixel data to be processed is gr, then the level data LVL is determined to be id from the point of intersection with the profile LD. In practice, the profile LD is stored in the form of a one-dimensional table on a memory (not shown) such as a ROM within the computer 1100, and the printer driver 1110 finds the level data by referencing this table. In step S302, it is determined whether or not the level data LVL that has been set as above is larger than the threshold value THL. Here, determination of whether the dots are on or off is performed using dithering. The threshold value THL is set to a different value for each pixel block of the so-called dither matrix. This embodiment uses a dither matrix in which a value from 0 to 254 is expressed for each square of a 16×16 square pixel block. FIG. 5 is a diagram illustrating how dots are determined to be on or off according to dithering. For the convenience of illustration, FIG. 5 shows only some of the K pixel data. First, the level data LVL of each K pixel data is compared with the threshold value THL of the pixel block on the dither matrix that corresponds to that K pixel data. Then, if the level data LVL is larger than the threshold value THL, the dot is set to on, and if the level data LVL is smaller, the dot is set to off. In this diagram, the pixel data of the shaded regions in the dot matrix are the K pixel data in which the dots are set to on (that is, dots are formed). In other words, in step S302, if the level data LVL is larger than the threshold value THL, then the procedure advances to step S310, and otherwise the procedure advances to step S303. Here, if the procedure is advanced to step S310, then the printer driver 1110 assigns a value of “11” to the K pixel data being processed, storing it as the pixel data (2-bit data) indicating a large dot, and then the procedure is advanced to step S311. Then, in step S311, it is determined whether or not all of the K pixel data have been processed, and if processing is finished, then halftone processing is ended, and if processing is not finished, then the K pixel data that have not yet been processed are set as the target of processing, and the procedure is returned to step S301. On the other hand, if the procedure is advanced to step S303, then the printer driver 1110 sets the medium dot level data LVM. The medium dot level data LVM is set using the creation ratio table mentioned above based on the gradation value. The setting method is the same as that for setting the large dot level data LVL. That is, in the example shown in FIG. 4, the level data LVM corresponding to the gradation value gr is found to be 2d, which is indicated by the point of intersection with the profile MD that indicates the medium dot creation ratio. Next, in step S304, the medium dot level data LVM is compared in size with the threshold value THM to determine whether or not the medium dot is on or off. The method by which dots are determined to be either on or off is the same that as that for large dots. However, when determining whether medium dots are on or off, the threshold values THM used for this determination are set to values that are different from the threshold values THL for large dots. That is, if the dots are determined to be on or off using the same dither matrix for the large dots and the medium dots, then the pixel blocks where the dot is likely to be on will be the same in both cases. That is, there is a high possibility that when a large dot is off, the medium dot will also be off. As a result, there is a possibility that the creation ratio of medium dots will be lower than the desired creation ratio. In order to prevent this problem, in the present embodiment there are different dither matrices for large dots and medium dots. That is, by changing the pixel blocks that are likely to be on between the large dots and the medium dots, the dots are formed appropriately. FIG. 6A and FIG. 6B show the relationship between the dither matrix that is used for assessing large dots and the dither matrix that is used for assessing medium dots. In this embodiment, the first dither matrix TM of FIG. 6A is used for the large dots. The second dither matrix UM of FIG. 6B is used for the medium dots. The second dither matrix UM is obtained by symmetrically shifting the threshold values in the first dither matrix TM about the center in the carrying direction (the vertical direction in these diagrams). As explained previously, the present embodiment uses a 16×16 matrix, but for convenience of illustration, FIG. 6 shows a 4×4 matrix. It should be noted that it is also possible to use completely different dither matrices for the large dots and medium dots. Then, instep S304, if the medium dot level data LVM is larger than the medium dot threshold value THM, then it is determined that the medium dot should be on, and the procedure is advanced to step S309, and otherwise the procedure is advanced to step S305. Here, if the procedure is advanced to step S309, then the printer driver 1110 assigns a value of “10” to the K pixel data being processed, storing it as pixel data indicating a medium dot, and then the procedure is advanced to step S311. Then, in step S311, it is determined whether or not all of the K pixel data have been processed, and if processing is finished, then halftone processing is ended, and if processing is not finished, then the K pixel data that have not yet been processed are set as the target of processing, and the procedure is returned to step S301. On the other hand, if the procedure is advanced to step S305, then the small dot level data LVS is set in the same way that the level data of the large dots and the medium dots are set. It should be noted that the dither matrix for the small dots is preferably different from those for the medium dots and the large dots, in order-to prevent a drop in the creation ratio of small dots as discussed above. Then, instep S306, the printer driver 1110 compares the level data LVS and the small dot threshold values THS, and if the small dot level data LVS is larger than the small dot threshold value THS, then the procedure is advanced to step S308, and otherwise the procedure is advanced to step S307. Here, if the procedure is advanced to step S308, then a value of “01” for pixel data that indicate a small dot is assigned to the K pixel data being processed and the data are stored, and then the procedure is advanced to step S311. Then, in step S311, it is determined whether or not all of the K pixel data have been processed, and if processing is not finished, then the K pixel data that have not yet been processed are set as the target of processing, and the procedure is returned to step S301. On the other hand, if processing is finished, then halftone processing for the K image data is ended, and halftone processing is performed in the same manner for the image data of the other colors. On the other hand, if the procedure is advanced to step S307, then the printer driver 1110 assigns a value of “00” to the K pixel data being processed and stores it as pixel data indicating that not dot is to be formed, and then the procedure is advanced to step S311. Then, in step S311, it is determined whether or not all of the K pixel data have been processed, and if processing is not finished, then the K pixel data that have not yet been processed are set as the target of processing, and the procedure is returned to step S301. On the other hand, if processing is finished, then halftone processing for the K image data is ended, and halftone processing is performed in the same way for the image data of the other colors. <Regarding Setting the Printer Driver> FIG. 7 is an explanatory diagram of the user interface of the printer driver 1110. The user interface of the printer driver 1110 is displayed on the display device 1200 via the video driver 1102. The user can use the input device 1300 to change the various settings of the printer driver 1110. The settings for “margin format mode” and “image quality mode” are prepared as the basic settings, and settings such as “paper size mode” are prepared as the paper settings. These modes are described later. ===Configuration of Printer=== <Configuration of Printer> FIG. 8 is a block diagram of the overall configuration of the printer 1 of this embodiment. Further, FIG. 9 is a schematic diagram of the overall configuration of the printer 1 of this embodiment. FIG. 10 is lateral sectional view of the overall configuration of the printer 1 of this embodiment. The basic structure of the printer 1 according to the present embodiment is described below using these diagrams. The inkjet printer 1 of this embodiment has a carrying unit 20, a carriage unit 30, a head unit 40, a sensor 50, and a controller 60. The printer 1 that receives print data from the computer 1100, which is an external device, controls the various units (the carrying unit 20, the carriage unit 30, and the head unit 40) using the controller 60. The controller 60 controls the units in accordance with the print data that are received from the computer 1100 to print an image on a paper S. The sensor 50 monitors the conditions within the printer 1, and it outputs the results of this detection to the controller 60. The controller 60 receives the detection results from the sensor 50, and controls the units based on these detection results. The carrying unit 20 is for feeding the paper S up to a printable position, and carrying the paper S by a predetermined carry amount in a predetermined direction (hereinafter, referred to as the “carrying direction”) during printing. Here, the carrying direction of the paper S is the direction that intersects the carriage movement direction described below, and corresponds to the “intersecting direction” of the claims. The carrying direction can also be referred to as the “sub-scanning direction.” In the following description, positions in the carrying direction may also be referred to as “sub-scanning positions.” The carrying unit 20 functions as a carrying mechanism for carrying the paper S. The carrying unit 20 has a paper feed roller 21, a carry motor 22 (also referred to as the “PF motor”), a carry roller 23, a platen 24, and a paper discharge roller 25. The paper feed roller 21 is a roller for automatically feeding paper S that has been inserted into a paper insert opening into the printer 1. The paper feed roller 21 has the cross-sectional shape of the letter D, and the length of its circumferential portion is set longer than the carry distance up to the carry roller 23. Thus, by rotating the paper feed roller 21 with its circumferential portion abutting against the paper surface, the paper S can be carried up to the carry roller 23. The carry motor 22 is a motor for carrying paper in the carrying direction, and is constituted by a DC motor, for example. The carry roller 23 is a roller for carrying the paper S that has been supplied by the paper feed roller 21 up to a printable region, and is driven by the carry motor 22. The platen 24 is for supporting the paper S during printing from the rear surface side of the paper S. The paper discharge roller 25 is a roller for discharging the paper S for which printing has finished in the carrying direction. The paper discharge roller 25 is rotated in synchronization with the carry roller 23. The carriage unit 30 is provided with a carriage 31 and a carriage motor 32 (hereinafter, also referred to as “CR motor”). The carriage motor 32 is a motor for moving the carriage 31 back and forth in a predetermined direction (hereinafter, this is also referred to as the “carriage movement direction”), and for example is constituted by a DC motor. The carriage 31 detachably holds ink cartridges 90 containing ink. A head 41 for ejecting ink from the nozzles is attached to the carriage 31. Thus, by moving the carriage 31 back and forth, the head 41 and the nozzles also move back and forth in the carriage movement direction. Consequently, the carriage movement direction corresponds to the “movement direction” in the claims. It should be noted that the carriage movement direction can also be referred to as the “main-scanning direction.” In the following description, positions in the carriage movement direction are also referred to as “main-scanning positions.” The head unit 40 is for ejecting ink onto the paper S. The head unit 40 has a head 41. The head 41 has a plurality of nozzles, and ejects ink intermittently from each of the nozzles. A raster line made of dots in the carriage movement direction is formed on the paper S due to the head 41 intermittently ejecting ink from the nozzles while moving in the carriage movement direction. This raster line corresponds to the “line” in the claims. It should be noted that the configuration of the head 41, the drive circuit for driving the head 41, and the method for driving the head 41 are described later. The sensor 50 includes a linear encoder 51, a rotary encoder 52, a paper detection sensor 53, and a paper width sensor 54, for example. The linear encoder 51 is for detecting the position in the carriage movement direction, and has a belt-shaped slit plate provided extending in the scanning direction, and a photo interrupter that is attached to the carriage 31 and detects the slits formed in the slit plate. The rotary encoder 52 is for detecting the amount of rotation of the carry roller 23, and has a disk-shaped slit plate that rotates in conjunction with rotation of the carry roller 23, and a photo interrupter for detecting the slits formed in the slit plate. The paper detection sensor 53 is for detecting the position of the front end of the paper S to be printed. The paper detection sensor 53 is provided at a position where it can detect the front end position of the paper S as the paper S is being carried toward the carry roller 23 by the paper feed roller 21. It should be noted that the paper detection sensor 53 is a mechanical sensor that detects the front end of the paper S through a mechanical mechanism. More specifically, the paper detection sensor 53 has a lever that can be rotated in the paper carrying direction, and this lever is disposed so that it protrudes into the path over which the paper S is carried. Further, as a result of the paper S being carried, the front end of the paper comes into contact with the lever and the lever is rotated. Thus, the paper detection sensor 53 detects the front end of the paper S and whether or not the paper S is present by detecting the movement of this lever using the photo interrupter, for example. The paper width sensor 54 is attached to the carriage 31. In the present embodiment, as shown in FIG. 11, it is attached at substantially the same position as the most upstream-side nozzle, as regards its position in the carrying direction. The paper width sensor 54 is an optical sensor 50, and with a light-receiving section, receives the reflection light of the light that has been irradiated onto the paper S from a light-emitting section. Then, based on the intensity of the light that is received by the light-receiving section, the sensor detects whether or not the papers is present. The paper width sensor 54 detects the positions of the ends of the paper S while being moved by the carriage 31, so as to detect the width of the paper S. The paper width sensor 54 also can detect the front end of the paper S depending on the conditions. The controller 60 is a control unit for carrying out control of the printer 1. The controller 60 has an interface section 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface section 61 exchanges data between the computer 1100, which is an external device, and the printer 1. The CPU 62 is a computer processing device for performing overall control of the printer. The memory 63 is for ensuring a working region and a region for storing the programs for the CPU 62, for instance, and includes memory means such as a RAM, an EEPROM, or a ROM. The CPU 62 controls the various units 20, 30, and 40 via the unit control circuit 64 in accordance with programs stored on the memory 63. In this embodiment, a partial region of the memory 63 is used as a correction value storage section 63a for storing correction values, which is described later. <Regarding the Configuration of the Head> FIG. 11 is an explanatory diagram showing the arrangement of the nozzles in the lower surface of the head 41. A black ink nozzle row Nk, a cyan ink nozzle row Nc, a magenta ink nozzle row Nm, and a yellow ink nozzle row Ny are formed in the lower surface of the head 41. Each nozzle row is provided with n pieces of nozzles (for example, n=180), which are ejection openings for ejecting the respective color inks. The plurality of nozzles of the nozzle rows are arranged in a row at a constant spacing (nozzle pitch: k•D) in the carrying direction. Here, D is the minimum dot pitch in the carrying direction, that is, the spacing at the highest resolution of the dots formed on the paper S. Further, k is an integer of 1 or more. For example, if the nozzle pitch is 180 dpi ( 1/180 inch) and the dot pitch in the carrying direction is 720 dpi ( 1/720), then k=4. It should be noted that in the example diagrammed here the nozzles of the nozzle rows are assigned numbers that become smaller toward the nozzles on the downstream side (#1 to #n). That is, the nozzle #1 is positioned more downstream in the carrying direction than the nozzle #n. When these nozzles rows are provided in the head 41, the region in which dots are formed by a single dot forming operation becomes wide, allowing the printing time to be reduced. Further, these nozzle rows are provided for each color of ink, and thus by suitably ejecting ink from these nozzle rows it is possible to perform multi-color printing. Further, pressure chambers (not shown) are provided on the ink path that is in communication with each nozzle. In each pressure chamber there is provided a piezo element (not shown) to serve as a drive element for causing ink droplets to be ejected from the respective nozzle. <Regarding Driving of the Head> FIG. 12 is an explanatory diagram of the drive circuit of the head 41. This drive circuit is provided within the unit control circuit 64 mentioned above. As shown in the diagram, the drive circuit is provided with an original drive signal generating section 644A and a drive signal shaping section 644B. In this embodiment, a drive circuit is provided for each nozzle row, that is, for each nozzle row of the colors black (K), cyan (C), magenta (M), and yellow (Y), such that the piezo elements are driven individually for each nozzle row. The number in parentheses at the end of the name of each of the signals in the diagram indicates the number of the nozzle to which that signal is supplied. The piezo element mentioned above is deformed each time a drive pulse W1 or W2 (see FIG. 13) is supplied thereto, changing the pressure on the ink within the pressure chamber. That is, when a voltage of a predetermined time duration is applied between electrodes provided at both ends of the piezo element, the piezo element becomes deformed for the time duration of voltage application and deforms an elastic membrane (lateral wall) which defines a portion of the pressure chamber. The volume of the pressure chamber changes in accordance with this deformation of the piezo element, and due to this change in the volume of the pressure chamber, the pressure on the ink within the pressure chamber is altered. Then, due to this change in pressure on the ink, an ink droplet is ejected from the corresponding nozzle #1 to #180. The original drive signal generating section 644A generates an original drive signal ODRV that is used in common by the nozzles #1 to #n. The original drive signal ODRV of the present embodiment is a signal that includes a plurality of drive pulses W1 and W2 during the main-scanning period of a single pixel (the time during which a single nozzle crosses over a grid corresponding to a single pixel). The drive signal shaping section 644B receives an original drive signal ODRV from the original drive signal generating section together with a print signal PRT(i). The drive signal shaping section 644B shapes the original drive signal ODRV in correspondence with the level of the print signal PRT(i) and outputs it toward the piezo elements of the nozzles #1 to #n as a drive signal DRV(i). The piezo elements of the nozzles #1 to #n are driven in accordance with the drive signal DRV from the drive signal shaping section 644B. <Regarding Drive Signals of the Head> FIG. 13 is a timing chart for explaining the various signals. That is, this drawing shows a timing chart for the various signals, these being an original drive signal ODRV, a print signal PRT(i), and a drive signal DRV(i). As discussed above, the original drive signal ODRV is a signal used in common for the nozzles #1 to #n, and is output from the original drive signal generating section 644A to the drive signal shaping section 644B. In this embodiment, the original drive signal ODRV includes two drive pulses, namely a first pulse W1 and a second pulse W2, in the period during which a single nozzle crosses over the length of one pixel. The first pulse W1 is a drive pulse for causing a small size ink droplet (hereinafter, called small ink droplet) to be ejected from the nozzle. Further, the second pulse W2 is a drive pulse for causing a medium size ink droplet (hereinafter, called medium ink droplet) to be ejected from the nozzle. That is, by supplying the first pulse W1 to the piezo element, a small ink droplet is ejected from the nozzle. When this small ink droplet lands on the paper S, a small size dot (small dot) is formed. Likewise, by supplying the second pulse W2 to the piezo element, a medium ink droplet is ejected from the nozzle. When this medium ink droplet lands on the paper S, a medium size dot (medium dot) is formed. The print signal PRT(i) is a signal corresponding to the pixel data allocated to a single pixel. That is, the print signal PRT(i) is a signal corresponding to the pixel data included in the print data. In this embodiment, the print signals PRT(i) are signals having two bits of information per pixel. It should be noted that the drive signal shaping section 644B shapes the original drive signal ODRV in correspondence with the level of the print signal PRT(i), and outputs a drive signal DRV(i). The drive signal DRV is a signal that is obtained by blocking the original drive signal ODRV in correspondence with the level of the print signal PRT. That is, when the level of the print signal PRT is “1” then the drive signal shaping section 644B allows the drive pulse for the original drive signal ODRV to pass unchanged and sets it as the drive signal DRV(i). On the other hand, when the level of the print signal PRT is “0,” the drive signal shaping section 644B blocks the drive pulse of the original drive signal ODRV. Then, the drive signal DRV(i) from the drive signal shaping section 644B is individually supplied to the corresponding piezo element. The piezo elements are driven according to the drive signals DRV(i) that have been supplied thereto. When the print signal PRT(i) corresponds to the two bits of data “01” then only the first pulse W1 is output in the first half of the pixel period. Accordingly, a small ink droplet is ejected from the nozzle, forming a small dot on the paper S. When the print signal PRT(i) corresponds to the two bits of data “10” then only the second pulse W2 is output in the later half of the pixel period. Accordingly, a medium ink droplet is ejected from the nozzle, forming a medium dot on the paper S. When the print signal PRT(i) corresponds to the two bits of data “11” then both the first pulse W1 and the second pulse W2 are output during the pixel period. Accordingly, a small ink droplet and a medium ink droplet are successively ejected from the nozzle, forming a large size dot (large dot) on the paper S. When the print signal PRT(i) corresponds to the two bits of data “00” then neither the first pulse W1 or the second pulse W2 are output during the pixel period. In this case, no ink droplet of any size is ejected from the nozzle, and a dot is not formed on the paper S. As described above, the drive signal DRV(i) in a single pixel period is shaped so that it may have four different waveforms corresponding to the four different values of the print signal PRT(i). Here, in the present embodiment, the content of the two-bit pixel data and the content of the print signals are matching. In other words, for all pixel data and print signals, non-formation of a dot is the two-bit data “00” and formation of a small dot is the two-bit data “01.” Further, formation of a medium dot is the two-bit data “10” and formation of a large dot is the two-bit data “11.” Consequently, the drive circuits of the head 41 use the pixel data included in the print data as the print signals PRT. <Regarding the Printing Operation> FIG. 14 is a flowchart of the operations during printing. The various operations that are described below are achieved by the controller 60 controlling the various units in accordance with a program stored in the memory. This program has codes for executing the various operations. Receive Print Command (S001): The controller 60 receives a print command via the interface section 61 from the computer 1100. This print command is included in the header of the print data transmitted from the computer 1100. The controller 60 then analyzes the content of the various commands included in the print data that are received and uses the various units to perform the following “paper feeding operation”, “carrying operation”, and “dot forming operation”, for example. Paper Feeding Operation (S002): Next, the controller 60 performs the paper feeding operation. The paper feeding operation is a process for moving the paper S, which is the object to be printed, and positioning it at a print start position (the so-called indexing position). That is, the controller 60 rotates the paper feed roller 21 to feed the paper S to be printed up to the carry roller 23. Then, the controller 60 rotates the carry roller 23 to position the paper S, which has been fed from the paper feed roller 21, at the print start position. It should be noted that when the paper S has been positioned at the print start position, at least some of the nozzles of the head 41 are in opposition to the paper S. Dot Formation Operation (S003): Next, the controller 60 performs the dot forming operation. The dot forming operation is an operation for intermittently ejecting ink from the head 41 moving in the carriage movement direction, so as to form dots on the paper S. The controller 60 drives the carriage motor 32 to move the carriage 31 in the carriage movement direction. Further, the controller 60 causes ink to be ejected from the head 41 in accordance with the print data during the period that the carriage 31 is moving. Then, as mentioned above, if ink that is ejected from the head 41 lands on the paper S, dots are formed on the paper S. Carrying Operation (S004): Next, the controller 60 performs the carrying operation. The carrying operation is a process for moving the paper S relative to the head 41 in the carrying direction. The controller 60 drives the carry motor 22 to rotate the carry roller 23 and thereby carry the paper S in the carrying direction. Through this carrying operation, the head 41 becomes able to form dots at positions that are different from the positions of the dots formed in the preceding dot forming operation. Paper Discharge Determination (S005): Next, the controller 60 determines whether or not to discharge the paper S that is being printed. In this determination, the paper is not discharged if there are still data to be printed to the paper S that is being printed. In this case, the controller 60 repeats in alternation the dot forming operation and the carrying operation until there are no longer any data for printing, thereby gradually printing an image made of dots on the paper S. When there are no longer any data for printing to the paper S that is being printed, the controller 60 discharges that paper S. That is, the controller 60 discharges the printed paper S to the outside by rotating the paper discharge roller 25. It should be noted that whether or not to discharge the paper can also be determined based on a paper discharge command that is included in the print data. Determining Whether Printing is Finished (S006): Next, the controller 60 determines whether or not to continue printing. If the next sheet of paper S is to be printed, then printing is continued and the paper feed operation for the next sheet of paper S is started. If the next sheet of paper S is not to be printed, then the printing operation is ended. ===Regarding the Print Mode=== Here, print modes that can be executed by the printer 1 of the present embodiment are described using FIG. 15A and FIG. 15B. Interlacing is available as an example of the print mode. By using an interlacing method, individual differences between the nozzles such as in the nozzle pitch and the ink ejection properties are lessened by spreading them out over the image to be printed, and thus an improvement in image quality can be attained. FIGS. 15A and 15B are explanatory diagrams of the interlacing method. It should be noted that for the sake of simplifying the description, the nozzle rows shown in place of the head 41 are illustrated as if they are moving with respect to the paper S, but the diagrams show the relative positional relationship between the head and the paper S, and in fact, it is the paper S that moves in the carrying direction. In the diagrams, the nozzles represented by a black circle are the nozzles that in practice eject ink, and the nozzles represented by white circles are nozzles that do not eject ink. It should be noted that FIG. 15A shows the nozzle positions in the first through fourth passes and how the dots are formed by those nozzles. FIG. 15B shows the nozzle positions in the first through sixth passes and how the dots are formed. Here, “pass” refers to a single movement of the nozzle rows in the carriage movement direction. “Raster line” is a row of dots lined up in the carriage movement direction. The “interlace mode” refers to a print mode in which k is at least 2 and at least one raster line that is not recorded is sandwiched between raster lines that are recorded in a single pass. In other words, it is a print mode in which at least one raster line that is not formed is set between raster lines that are formed in a single dot forming operation, and through a plurality of dot forming operations, the lines are formed in a complementary manner, forming adjacent raster lines with different nozzles. With the interlace mode illustrated in FIG. 15A and FIG. 15B, each time the paper S is carried in the carrying direction by a constant carry amount F, the nozzles form a raster line immediately above the raster line that was recorded in the immediately-prior pass. In order to form the raster lines in this way using a constant carry amount, the number N (integer) of nozzles that actually eject ink is coprime to k, and the carry amount F is set to N•D. In the example of the drawings, the nozzle row has four nozzles arranged in the carrying direction. However, since the nozzle pitch k of the nozzle group is 4, in order to fulfill the condition for forming raster lines using a constant carry amount, the condition being “N and k are coprime to one another,” not all the nozzles can be used. Accordingly, three of the four nozzles are used to perform the interlace mode. Furthermore, because three nozzles are used, the paper S is carried by a carry amount 3•D. As a result, for example, a nozzle row with a nozzle pitch of 180 dpi (4•D) is used to form dots on the paper S at a dot pitch of 720 dpi (=D). These diagrams show the manner in which continuous raster lines are formed, with the first raster line being formed by the nozzle #1 in the third pass, the second raster line being formed by the nozzle #2 in the second pass, the third raster line being formed by the nozzle #3 in the first pass, and the fourth raster line being formed by the nozzle #1 in the fourth pass. It should be noted that ink is ejected from only nozzle #3 in the first pass, and ink is ejected from only nozzle #2 and nozzle #3 in the second pass. The reason for this is that when ink is ejected from all of the nozzles in the first and second passes, it is not possible to form continuous raster lines on the print paper S. It should be noted that, from the third pass on, three nozzles (#1 to #3) eject ink and the paper S is carried by a constant carry amount F (=3•D), forming continuous raster lines at the dot pitch D. ===Regarding Borderless Printing and Bordered Printing=== With the printer 1 of the present embodiment, it is possible to execute both so-called “borderless printing,” in which printing is performed without forming margins on the ends of the paper S, and so-called “bordered printing,” in which printing is carried out forming margins at the ends of the paper S. <Overview of Borderless Printing and Bordered Printing> With bordered printing, printing is performed such that the print region, which is the region to which ink is ejected according to the print data, is contained within the paper S. FIG. 16 is a diagram showing the relationship in size between the print region A and the paper S during bordered printing. As shown in the diagram, the print region A is set so that it is contained within the paper S, forming margins on the top and bottom ends and on the left and right lateral ends of the paper S. When performing bordered printing, the printer driver 1110 converts, in the resolution conversion process, the resolution of the image data to a designated print resolution while processing the image data so that the print region A is located inward from the edges of the paper S by a predetermined width. For example, if the image data does not fit within a predetermined width from the edges when printing at the print resolution that has been set for the print region A, then the pixel data corresponding to the ends of that image are removed by suitably performing trimming etc., making the print region A smaller. On the other hand, with borderless printing, printing is executed such that the outer circumference portion of the print region A extends beyond the paper S. FIG. 17 shows the relationship in size between the print region A and the paper S during borderless printing. As shown in this diagram, the print region A is set to include the region extending beyond the upper and lower ends and the right and left lateral edges of the paper S (hereinafter, referred to as the “abandonment region Aa”). Ink is ejected onto this abandonment region Aa as well. By ejecting ink onto the abandonment region Aa, ink is reliably ejected toward the ends of the paper S, even if there is some shift in the position of the paper S with respect to the head 41 due, for example, to the precision of the carrying operation, thus achieving printing without forming margins at the ends. It should be noted that in this abandonment region Aa, the region that extends beyond the upstream end of the paper S (the lower end of the paper S) and the region that extends beyond the downstream end of the paper S (the upper end of the paper S) can be expressed as the “region that is determined to be outside, on the upstream side, of the upstream-side end in the intersecting direction of the medium” and the “region that is determined to be outside, on the downstream side, of the downstream-side end,” respectively. When performing borderless printing, the printer driver 1110 converts, in the resolution conversion process, the resolution of the image data to a designated print resolution while processing the image data so that the print region A extends beyond the edges of the paper S by a predetermined width. For example, if the image data extend too far beyond the paper S when printing at the print resolution that has been set for the print region A, then the image data are suitably trimmed, for example, so that the amount by which the print region A extends beyond the paper S becomes a predetermined width. It should be noted that paper size information regarding the standard dimensions of the paper S, such as the A4 size, are stored in advance in the memory of the computer 1100. The paper size information for example indicates the number of dots (D) in the carriage movement direction and the carrying direction for that size. Further, this paper size information is stored corresponding with the paper size mode that is input through the user interface of the printer driver 1110. Then, when processing the image data, the printer driver 1110 references the paper size information corresponding to that paper size mode to find the size of the paper S, and then processing is performed. <Regarding the Nozzles Used in Borderless Printing and Bordered Printing> As mentioned above, with borderless printing, ink is ejected toward the abandonment region Aa as well, which is the region outside of the upper end and the lower end of the paper S. Thus, there is a possibility that the ink that is abandoned will adhere to the platen 24 and cause the platen 24 to become dirty. Accordingly, the platen 24 is provided with grooves for collecting the ink that is outside of the upper end and the lower end of the paper S. Then, when printing the upper end and the lower end of the paper S, use of the nozzles is restricted such that ink is ejected from only the nozzles that are in opposition to that groove. FIGS. 18A to 18C show the positional relationship between the grooves provided in the platen 24 and the nozzles. It should be noted that for the convenience of description, a nozzle row of n=7, that is, a nozzle row provided with nozzles #1 to #7, is used as an example. It should be noted that as shown in FIG. 18A, the upstream side and the downstream side in the carrying direction respectively correspond to the lower-end side and the upper-end side of the paper S. As shown in FIG. 18A, grooves are provided in two positions of the platen 24, these being a portion on the downstream side and a portion on the upstream side in the carrying direction, over a length that exceeds the width of the paper S. The nozzles #1 to #3 are in opposition to the downstream groove, and the nozzles #5 to #7 are in opposition to the upstream groove. Then, as shown in FIG. 18A, when printing the upper end of the paper S (the downstream-side end in the carrying direction), printing is performed using the nozzles #1 to #3 (hereinafter, this is referred to as “upper end processing”), and as shown in FIG. 18B, when printing the lower end (the upstream-side end in the carrying direction), printing is performed using the nozzles #5 to #7 (hereinafter, this is referred to as “lower end processing”), and the intermediate portion between the upper end and the lower end is printed using all of the nozzles #1 to #7 as shown in FIG. 18C (hereinafter, this is referred to as “intermediate processing”). Here, as shown in FIG. 18A, when printing the upper end of the paper S, the ejection of ink from the nozzles #1 to #3 is started before the upper end arrives at the downstream groove. At this time, the abandoned ink that does not land on the paper S is absorbed by an absorbing material that is accommodated within the downstream side groove, thus keeping the platen 24 from becoming dirty. Further, as shown in FIG. 18B, when printing the lower end of the paper S, the ejection of ink from the nozzles #5 to #7 is continued even after that lower end has passed over the upstream groove. At this time, the abandoned ink that does not land on the paper S is absorbed by an absorbing material that is accommodated within the upstream side groove, and thus again, it is possible to prevent the platen 24 from becoming dirty. On the other hand, in bordered printing, a margin is formed at the ends of the paper S, and thus ink is not ejected toward the abandonment region Aa, which is the region outside of the upper end and the lower end of the paper S. Consequently, it is always possible to start and end the ejection of ink in a state where the paper S is in opposition to a nozzle, and thus unlike with borderless printing, there is no limitation to which nozzles are used. For this reason, all of the nozzles #1 to #7 are used to print on the entire length of the paper S. ===Regarding the Processing Mode=== The user can select “borderless printing” or “bordered printing” through the user interface of the printer driver 1110. That is, as shown in FIG. 7, the two buttons “bordered” and “borderless” are displayed on the user interface as the input buttons of the margin format mode for designating the margin format. It is also possible to select the image quality mode for specifying the image quality of the image from the screen of the user interface, and on this screen are displayed the two buttons “normal” and “fine” as the input buttons of the image quality mode. If the user has input “normal,” then the printer driver 1110 sets the print resolution mentioned above to 360×360 dpi, for example. On the other hand, if “fine” has been input, then the printer driver 1110 sets the print resolution to 720×720 dpi, for example. It should be noted that as shown in the first reference table of FIG. 19, a print mode is prepared for each combination of margin mode and image quality mode. Further, a processing mode(s) is correlated to each of these print modes as shown in the second reference table in FIG. 20. It should be noted that the first reference table and the second reference table are stored on the memory of the computer 1100, for example. The processing modes are for defining the dot forming operation and the carrying operation. The printer driver 1110 converts, through the series of processes from the resolution conversation process to the rasterizing process, the image data into print data that match the format of the processing mode that has been set. It should be noted that if the processing modes are different, then print processing in which at least one of the dot forming operation and the carrying operation is different are performed. Here, print processing in which the dot forming operations are different refers to print processing in which the patterns of change in the nozzles that are used in the dot forming operations are different. On the other hand, print processing in which the carrying operations are different refers to print processing in which the patterns of change in the carry amount of the carrying operations are different. These are described later using specific examples. <Specific Examples of the Processing Modes> The printer 1 is provided with six types of processing modes, these being for example a first upper end processing mode, a first intermediate processing mode, a first lower end processing mode, a second upper end processing mode, a second intermediate processing mode, and a second lower end processing mode, serving as the print processing in which at least one of the dot forming operations and the carrying operations is different. The first upper end processing mode is a processing mode for executing the upper end processing mentioned above at a print resolution of 720×720 dpi. In other words, it is a processing mode in which printing through interlacing using only nozzles #1 to #3 is performed in principle in the first half pass numbers. It should be noted that the carry amount F of the paper S is 3•D because three nozzles are used (see FIG. 21A). The first intermediate processing mode is a processing mode for executing the intermediate processing mentioned above at a print resolution of 720×720 dpi. In other words, it is a processing mode in which printing through interlacing using all of the nozzles of the nozzle row (nozzles #1 to #7) is performed in all of the passes. It should be noted that the carry amount F of the paper S is 7•D because seven nozzles are used (see FIG. 21A and FIG. 21B). The first lower end processing mode is a processing mode for executing the lower end processing mentioned above at a print resolution of 720×720 dpi. In other words, it is a processing mode in which printing through interlacing using only nozzles #5 to #7 is performed in principle in the later half pass numbers. It should be noted that the carry amount of the paper S is 3•D because three nozzles are used (see FIG. 21B). The second upper end processing mode is a processing mode for executing the upper end processing mentioned above at a print resolution of 360×360 dpi. In other words, it is a processing mode in which printing through interlacing using only nozzles #1 to #3 is performed in principle in the first half pass numbers. However, due to the print resolution being half as fine as that of the first upper end processing mode, the carry amount F of the paper S is 6•D, which is twice that of the first upper end processing mode (see FIG. 23A). The second intermediate processing mode is a processing mode for executing the intermediate processing mentioned above at a print resolution of 360×360 dpi. In other words, it is a processing mode in which printing through interlacing using all of the nozzles of the nozzle row (nozzles #1 to #7) is performed in all of the passes. However, due to the print resolution being half as fine as that of the first intermediate processing mode, the carry amount F of the paper S is 14•D dots, which is twice that of the first intermediate processing mode (see FIG. 23A and FIG. 23B). The second lower end processing mode is a processing mode for executing the lower end processing mentioned above at a print resolution of 360×360 dpi. In other words, it is a processing mode in which printing through interlacing using only nozzles #5 to #7 is performed in principle in the later half pass numbers. However, due to the print resolution being half as fine as that of the first lower end processing mode, the carry amount F of the papers is 6•D, which is twice that of the first lower end processing mode (see FIG. 23B). Here, the manner in which the image is formed on the paper S through these processing modes is described with reference to FIG. 21A to FIG. 24B. It should be noted that in all of these diagrams, the pair of diagrams A and B express the manner in which a single image is formed. In other words, FIG. A shows which nozzle in what pass of what processing mode the raster lines on the upper side portion of the image are formed, and FIG. B shows which nozzle in what pass of what processing mode the raster lines on the lower side portion of the image are formed. The left side portions of FIG. 21A through FIG. 24B (hereinafter referred to as the “left diagrams”) show the relative position of the nozzle row with respect to the paper S in each pass of the processing modes. It should be noted that in the left diagrams, for the convenience of description, the nozzle row is shown moving downward in increments of the carry amount F for each pass, but in actuality, it is the paper S that is moved in the carrying direction. Further, the nozzle row has nozzles #1 to #7, their nozzle number shown surrounded by a circle, and their nozzle pitch k•D is 4•D. Further, the dot pitch D is 720 dpi ( 1/720 inch). It should be noted that in this nozzle row the nozzles shown shaded in black are the nozzles that eject ink. The right side portions of FIG. 21A through FIG. 24B (hereinafter referred to as the “right diagrams”) show how the dots are formed by ejecting ink toward the pixels making up the raster lines. It should be noted that, as mentioned earlier, “pixels” are the virtually determined square grids on the paper for defining the positions where ink is made to land to form dots. The square grids in the right diagrams each express a 720×720 dpi pixel, that is, a square pixel having the length D in the four directions. The numbers written in each square indicate the number of the nozzle that ejects ink toward that pixel, and the squares in which no numbers are written indicate pixels in which ink is not ejected. Further, as shown in the right diagrams, the raster line on the uppermost end that can be formed through the dot formation processing is called the first raster line R1. Thereafter, in the direction toward the lower-end side of the paper S the raster lines are successively the second raster line R2, the third raster line R3, etc. (1) Regarding the Case of Printing an Image Using the First Upper End Processing Mode, the First Intermediate Processing Mode, and the First Lower End Processing Mode This case corresponds to an instance in which the first print mode shown in FIG. 19 and FIG. 20 has been set, that is, an instance in which “borderless” has been set as the margin format mode and “fine” has been set as the image quality mode. As shown in FIG. 21A and FIG. 21B, the printer 1 performs eight passes in the first upper end processing mode, then performs nine passes in the first intermediate processing mode, and then performs eight passes in the first lower end processing mode. As a result, ink is ejected at a print resolution of 720×720 dpi to the region R7 to R127 from the seventh raster line R7 to the 127th raster line R127 as a print region A, thereby borderlessly printing on a paper S of a later-described “first size”, which is 110•D in the carrying direction (paper length). It should be noted that the numbers of passes for the first upper end processing mode and the first lower end processing mode are fixed values, and for example do not change from the eight passes mentioned above, but the number of passes of the first intermediate processing mode is set changed in correspondence with the paper size mode that has been input through the user interface of the printer driver 1110. This is because, in order to perform borderless printing it is necessary for the size of the print region A to be larger in the carrying direction than the paper S corresponding to the paper size mode, and the size of the print region A is adjusted by changing the number of passes in the intermediate processing mode. In the example of the diagrams, the “first size,” which indicates that the size in the carrying direction is 110•D, has been input as the paper size mode. Then, the number of passes of the first intermediate mode is set to nine passes as mentioned above so that the size in the carrying direction of the print region A becomes 121•D. It should be noted that this is explained in detail later. In the first upper end processing mode, the dot forming operation of a single pass is executed through interlacing between the carrying operations, each of which in principle carries the paper S by 3•D, as shown in the left diagram of FIG. 21A. In the four passes of the first half of this processing mode, printing is performed using nozzles #1 to #3. In the four passes of the latter half, printing is performed while increasing the nozzle number by one each time the pass number advances, in the order of nozzle #4, nozzle #5, nozzle #6, and nozzle #7. That is, in the fifth pass, nozzles #1 to #4 are used, and in the sixth pass, nozzles #1 to #5 are used. In the seventh pass, nozzles #1 to #6 are used, and in the eighth pass, nozzles #1 to #7 are used. It should be noted that in the four latter half passes, the reason why the number of nozzles used is successively increased is to make the manner in which the nozzles are used match that of the first intermediate processing mode that is executed immediately afterward. In other words, ink is ejected in order from the nozzles on the side near the nozzles #1 to #3 so that ink can be ejected from all the nozzles #1 to #7 at the point that the first intermediate processing mode is started. Printing through the first upper end processing mode results in raster lines formed over the regions R1 to R46, from the first raster line R1 to the 46th raster line R46, shown in the right diagram (in the right diagram, the raster lines that are formed by the first upper end processing mode are shown shaded). Of these regions R1 to R46, the regions R7 to R28 corresponding to raster line R7 to raster line R28 are complete, with all of the raster lines being formed. However, the regions R1 to R6, which correspond to the raster lines R1 to R6, and the regions R29 to R46, which correspond to raster line R29 to raster line R46, are incomplete, with unformed sections being present in each of these raster lines. Of these, the former region R1 to R6 is a so-called unprintable region. That is, nozzles do not pass over the sections corresponding to the second, third, and sixth raster lines R2, R3, and R6 in any pass number. For this reason, dots cannot be formed in those pixels. Thus, the region R1 to R6 is not used for recording the image, and is excluded from the print region A. On the other hand, the yet unformed sections of the raster lines in the later region R29 to R46 are formed in a complementary manner through the first intermediate processing mode that is executed immediately afterwards, and this region R29 to R46 is completed at that time. In other words, the region R29 to R46 is a region that is completed through both the first upper end processing mode and the first intermediate processing mode, and hereinafter this region R29 to R46 is referred to as the “upper-end/intermediate mixed region.” Further, the region R7 to R28 that is formed through only the first upper end processing mode is referred to as the “upper-end-only region.” In the first intermediate processing mode, the dot forming operation of a single pass is executed in an interlacing manner between carrying operations, each of which in principle carries the paper S by 7•D, as shown in the left diagrams of FIG. 21A and FIG. 21B. All the nozzles #1 to #7 are used for printing in all of the passes, from the first pass to the ninth pass, at this time. As a result, raster lines are formed over the region R29 to R109, from the 29th raster line R29 to the 109th raster line R109 shown in the right diagram. More specifically, with regard to the upper-end/intermediate mixed region R29 to R46, the raster lines R29, R33, R36, R37, R40, R41, R43, R44, and R45, which were unformed in the first upper end processing mode, are formed in a complementary manner. In other words, these are formed by filling in the raster lines buried between the raster lines that have already been formed. By doing this, the upper-end/intermediate mixed region R29 to R46 becomes complete. All of the raster lines of the region R47 to R91 are completely formed through only the dot forming operations of the first intermediate processing mode. Hereinafter, the region R47 to R91, which is completed through only the first intermediate processing mode, is referred to as the “intermediate-only region.” The region R92 to R109 includes some raster lines with unformed portions, and these are formed in a complementary manner through the first lower end processing mode that is executed next, completing the region R92 to R109. In other words, the region R92 to R109 is a region that is completed through both the first intermediate processing mode and the first lower end processing mode. Hereinafter, the region R92 to R109 is referred to as the “intermediate/lower-end mixed region.” It should be noted that in the right diagram the raster lines that are formed through the first lower end processing mode are shown shaded. In the first lower end processing mode, as shown in FIG. 21B, the dot forming operation of a single pass is executed in an interlacing manner between carrying operations, each of which in principle carries the paper S by 3•D. In the five passes of the later half of the first lower end processing mode, printing is executed using nozzles #5 to #7. Further, in the three passes of the first half of the first lower end processing mode, printing is carried out while decreasing the nozzle number of the nozzles that are used by one in the order of nozzle #1, nozzle #2, and nozzle #3 each time the pass number increases. That is, printing is executed in the first pass using nozzles #2 to #7, in the second pass using nozzles #3 to #7, and in the third pass using nozzles #4 to #7. It should be noted that the reason why the nozzle number used in the three passes of the first half is successively decreased is to make the manner in which the nozzles are used match that of the five latter half passes that are executed immediately thereafter (the fourth pass of the lower end processing through the eighth pass of the first lower end processing). The result of printing in the first lower end processing mode is that raster lines are formed over the region R92 to R133, from the 92nd raster line R92 to the 133rd raster line R133 shown in the right diagram. More specifically, with regard to the intermediate/lower-end mixed region R92 to R109, the raster lines R92, R96, R99, R100, R103, R104, R106, R107, and R108, which were not formed in the first intermediate processing mode, are each formed in a complementary manner, completing the intermediate/lower-end mixed region R92 to R109. All the raster lines of the region R110 to R127 are formed through only the dot forming operations of the first lower end processing mode, completing this region. Hereinafter, the region R110 to R127 that is formed through only the lower end processing mode is referred to as the “lower-end-only region.” Further, the region R128 to R133 is a so-called unprintable region, that is, nozzles do not pass over the regions corresponding to the 128th, 131st, and 132nd raster lines R128, R131, and R132 in any pass number, and thus it is not possible to form dots in those pixels. Therefore, the region R128 to R133 is not used for recording the image, and is excluded from the print region A. Incidentally, in the case of printing using the first upper end processing mode, the first intermediate processing mode, and the first lower end processing mode, the print start position (the target position on the upper end of the paper S when printing is started) can be set to the fourth raster line, on the lower end side, from the uppermost end of the print region A (in FIG. 21A, the tenth raster line R10). In other words, the target position on the paper upper end when printing is started should be set toward the lower end of the print region A (the upstream side in the carrying direction) by a predetermined margin from the upper end position of the print region A (the position corresponding to the spot where the seventh raster line R7 is formed). By doing this, even if, due to carry error, the paper S is carried more than the stipulated carry amount, as long as that error is within 3•D, the upper end of the paper S is positioned more toward the lower end than the uppermost end of the print region A. Consequently, borderless printing can be reliably achieved without a blank region being formed on the upper end of the paper S. Conversely, if due to carry error the paper S is carried less than the stipulated carry amount, then as long as that amount is within 14•D, the upper end of the paper S is positioned more on the upper-end side than the 24th raster line R24, and thus the upper end of the paper S is printed by only the nozzles #1 to #3 above the groove, reliably preventing the platen 24 from becoming dirty. On the other hand, the print end position (the target position on the lower end of the paper S when printing is finished) can be set to the ninth raster line, on the upper end side, from the lowermost end of the print region A (in FIG. 21B, the 119th raster line R119), for example. In other words, the target position on the paper lower end when printing is finished should be set on the upper-end side of the print region A (the downstream side in the carrying direction) by a predetermined margin from the lower end position of the print region A (the position corresponding to the spot where the 121st raster line R121 is formed). By doing this, even if, due to carry error, the paper S is carried less than the stipulated carry amount, as long as that error is within 8•D, the lower end of the paper S is positioned more on the upper-end side than the raster line R127 on the lowermost end of the print region A. Consequently, borderless printing can be reliably achieved without a blank region being formed on the lower end of the paper S. Conversely, if due to carry error the paper S is carried more than the stipulated carry amount, then as long as that amount is within 12•D, the lower end of the paper S is positioned more on the lower-end side than the 106th raster line R106, and thus the lower end of the paper S is printed by only the nozzles #5 to #7 above the groove, reliably preventing the platen 24 from becoming dirty. It should be noted that the print start position and the print end position are related to the number of passes that are set in the first intermediate processing mode mentioned above. In other words, to satisfy the conditions of the print start position and the print end position mentioned above with respect to a paper S that corresponds to the paper size mode, first the size in the carrying direction of the print region A must be set to a size that extends beyond the upper end and the lower end of the paper S by 3•D and 8•D, respectively. This is because it is necessary to set the size in the carrying direction to larger than the paper S by 11•D. Consequently, the number of passes in the first intermediate processing mode is set such that the size is larger by 11•D than the size in the carrying direction, which is indicated by the paper size mode that has been input. Incidentally, the size in the carrying direction of the “first size” mentioned above is 110•D. To set the print region A to 121•D, which is larger than 110•D by 11•D, the number of passes of the first intermediate processing mode is set to nine passes. (2) Regarding a Case Where an Image is Printed Using Only the First Intermediate Processing Mode This case corresponds to an instance in which the second print mode shown in FIG. 19 and FIG. 20 has been set, that is, an instance in which “bordered” has been set as the margin format mode and “fine” has been set as the image quality mode. As shown in FIG. 22A and FIG. 22B, the printer 1 performs nine passes in the first intermediate processing mode. As a result, ink is ejected at a print resolution of 720×720 dpi onto the region R19 to R119, which serves as the print region A, printing on a paper S of the “first size,” which is 110•D in the carrying direction, leaving a border. It should be noted that like case (1) mentioned above, the number of passes of the first intermediate processing mode changes depending on the paper size mode that has been input. In other words, the number of passes is set such that the size of the print region A is a size with which a margin of a predetermined width is formed on the upper and lower ends of a paper S of the print size mode that has been input. In the example of the diagrams, “first size” has been input as the paper size mode, wherein the size of the paper S in the carrying direction is 110•D. Thus, in order to print on the paper S leaving a border, the number of passes of the first intermediate processing is set to 17 passes, as mentioned above, such that the size in the carrying direction of the print region A is 101•D. As mentioned above, bordered printing is printing forming a margin at the upper end and the lower end of the paper S. Consequently, it is not necessary to use only the nozzles in opposition to the groove to print on the upper end and the lower end. Thus, printing is executed according to only the first intermediate processing mode, in which all of the nozzles #1 to #7 are used over the entire length in the carrying direction of the paper S. In the first intermediate processing mode, the dot forming operation of a single pass is performed in an interlacing manner between carrying operations, each with which the paper S is carried by 7•D. Then, in the example of the diagrams, all of the nozzles #1 to #7 are used in all of the passes, from the first pass to the seventh pass, resulting in raster lines being formed over the region from the 19th raster line R19 to the 119th raster line R119. However, the region R1 to R18 on the upper-end side includes sections in which raster lines are not formed in any of the passes, such as R18, and thus the region R1 to R18 is an “unprintable region” and is excluded from the print region A. Similarly, the region R120 to R137 on the lower-end side includes sections in which raster lines are not formed in any of the passes, such as R120, and thus this region R120 to R137 also is an “unprintable region” and is excluded from the print region A. Consequently, in the remaining region R19 to R119 all the raster lines are formed through only the first intermediate processing mode. These regions R19 to R119 correspond to the intermediate-only region mentioned above. (3) Regarding a Case Where an Image is Printed Using the Second Upper End Processing Mode, the Second Intermediate Processing Mode, and the Second Lower End Processing Mode This case corresponds to an instance in which the third print mode shown in FIG. 19 and FIG. 20 has been set, that is, an instance in which “borderless” has been set as the margin format mode and “normal” has been set as the image quality mode. As shown in FIG. 23A and FIG. 23B, the printer 1 performs four passes in the second upper end processing mode, five passes in the second intermediate processing mode, and three passes in the second lower end processing mode. As a result, ink is ejected at a print resolution of 360×360 dpi to the region R3 to R64, which serves as the print region A, borderlessly printing a paper S of the “first size.” It should be noted that because the print resolution is 360×360 dpi, every other grid square shown in the right diagram is buried by a dot. In other words, the raster lines of the print region A are formed every other square. As in case (1) above, the number of passes in the second upper end processing mode and the second lower end processing mode is fixed and does not change, but the number of passes in the second intermediate processing mode changes depending on the paper size mode. In other words, in order to borderlessly print on a paper S of any paper size mode reliably, the number of passes of the second intermediate processing mode is set such that the size of the print region A is larger than the size of the paper S by 14•D. It should be noted that the value 14•D is determined so that the print start position becomes the fourth raster line, on the lower-end side, from the uppermost end of the print region A (the sixth raster line R6 in FIG. 23A), and that the print end position becomes the fourth raster line, on the upper-end side, from the lowermost end of the print region A (the 61st raster line R61 in FIG. 23B). In the example of the drawings, “first size” has been input and thus the size of the paper S in the carrying direction is 110•D, and therefore the number of passes of the second intermediate processing mode is set to five passes such that the size in the carrying direction of the print region A becomes 124•D (=110•D+14•D). The dot formation processing of the processing modes is described in detail below. In the second upper end processing mode, the dot forming operation of a single pass is executed in an interlacing manner between the carrying operations, each of which in principle carries the paper S by 6•D, as shown in the left diagram of FIG. 23A. In the first two passes of the second upper end processing mode, printing is performed using nozzles #1 to #3. In the second two passes, printing is performed while increasing the nozzle number of the nozzles that are used by two each time the pass number advances, in the order of nozzle #4, nozzle #5, nozzle #6, and nozzle #7. It should be noted that the reason for successively increasing the number of nozzles that are used is the same as in the case (1) discussed above. The result of printing through the second upper end processing mode is that raster lines are formed over the region R1 to R22 shown in the right diagram (in the right diagram, the raster lines that are formed are shown shaded). However, the completed region in which all of the raster lines have been formed, which corresponds to the upper-end-only region mentioned above, is only the region R3 to R16, and the region R1 to R2 and the region R17 to R22 are incomplete because they include some unformed raster lines. Of these, the former region R1 to R2 is an unprintable region because raster lines are not formed in the section corresponding to the second raster line R2 in any pass number, and is excluded from the print region A. On other hand, the latter region R17 to R22 corresponds to the upper-end/intermediate mixed region, and the unformed raster lines in the region R17 to R22 are completed, being formed in a complementary manner, in the second intermediate processing mode that is executed immediately thereafter. In the second intermediate processing mode, the dot forming operation of a single pass is executed in an interlacing manner between carrying operations, each of which in principle carries the paper S by 14•D, as shown in the left diagrams of FIG. 23A and FIG. 23B. All the nozzles #1 to #7 are used for printing in all of the passes at this time, from the first pass to the fifth pass, and as a result, raster lines are formed over the region R17 to R57 shown in the right diagram. More specifically, with regard to the upper-end/intermediate mixed region R17 to R22, the raster lines R17, R19, and R21, which were unformed in the second upper end processing mode, are each formed in a complementary manner, becoming complete. The region R23 to R51 corresponds to the intermediate-only region, and the region R23 to R51 is completed, all of the raster lines being formed through only the dot forming operations of the second intermediate processing mode. Moreover, the region R52 to R57 corresponds to the intermediate/lower-end mixed region and includes some raster lines that have not been formed, but these are formed in a complementary manner through the second lower end processing mode that is performed immediately thereafter, completing these regions R52 to R57. It should be noted that in the right diagram the raster lines that are formed through the second lower end processing mode only are shown shaded. In the second lower end processing mode, the dot forming operations of a single pass are executed in an interlacing manner between the carrying operations, each of which in principle carries the paper S by 6•D, as shown in FIG. 23B. In the single pass of the latter half of the second lower end processing mode, printing is performed using nozzles #5 to #7. Further, in the two first half passes of the second lower end processing mode, printing is performed while the nozzle number of the nozzles that are used is reduced by two each time the pass number advances, in the order of nozzle #1, nozzle #2, nozzle #3, and nozzle #4. It should be noted that the reason for successively reducing the number of nozzles that are used is the same as in the case (1) discussed above. The result of printing through the second lower end processing mode is that raster lines are formed over the region R48 to R66 shown in the right diagram. More specifically, the intermediate/lower-end mixed region R52 to R57 is completed, the raster lines R52, R54, and R56 that were unformed in the second intermediate processing mode each being formed in a complementary manner. Further, the region R58 to R64 corresponds to the lower-end-only region, and is completed by all the raster lines that are formed through only the dot forming operations of the second lower end processing mode. It should be noted that the remaining region R65 to R66 is an unprintable region because raster lines are not formed in the section corresponding to the 65th raster line R65 in any pass number, and thus is excluded from the print region A. (4) Regarding a Case in which an Image is Printed Using Only the Second Intermediate Processing Mode This case corresponds to an instance in which the fourth print mode shown in FIG. 19 and FIG. 20 has been set, that is, an instance in which “bordered” has been set as the margin format mode and “normal” has been set as the image quality mode. As shown in FIG. 24A and FIG. 24B, the printer 1 performs eight passes in the second intermediate processing mode. As a result, ink is ejected at a print resolution of 360×360 dpi onto the region R7 to R56 serving as the print region A, printing a paper S of the “first size” leaving a border. It should be noted that like case (2) mentioned above, the number of passes of the second intermediate processing mode changes depending on the paper size mode. In the example of the diagrams, “first size” has been input, and thus in order to print a paper S whose size is 110•D while leaving a border, the number of passes is set to a pass number such that the size in the carrying direction of the print region A is 100•D. For this reason, the number of passes of the second intermediate processing mode is set to eight passes. It should be noted that in bordered printing, the reason for printing through the second intermediate processing mode is the same as in the case (2) discussed above. In the second intermediate processing mode, the dot forming operation of a single pass is performed in an interlacing manner between carrying operations, each with which the paper S is carried by 14•D. Then, in the example of the diagrams, all of the nozzles #1 to #7 are used in all of the passes, from the first pass to the eighth pass, resulting in raster lines being formed over the region spanning the region R7 to R56. It should be noted that the region from R1 to R6 on the upper-end side includes sections in which raster lines are not formed in any of the passes, such as the section of R6, and thus the region R1 to R6 is an unprintable region and is excluded from the print region A. Similarly, the region R57 to R62 on the lower-end side includes sections in which raster lines are not formed in any of the passes, such as the section of R57, and thus this region R57 to R62 also is an unprintable region and is excluded from the print region A. It should be noted that in the remaining region R7 to R56 all of the raster lines are formed through only the second intermediate processing mode, and thus this corresponds to the intermediate-only region. Incidentally, the first upper end processing mode, first intermediate processing mode, first lower end processing mode, second upper end processing mode, second intermediate processing mode, and second lower end processing mode described above can each be considered different modes. This is because the relationship between the six corresponds to a relationship where printing is performed with at least one of at least the dot forming operation and the carrying operation being different. In other words, print processing in which the carrying operation is different refers to print processing in which the pattern of change in the carry amount F of the carrying operations (the carry amount F for each pass) is different. In regard to this, the pattern of change in the first intermediate processing mode is 7•D for all the passes, the pattern of change in the second intermediate processing mode is 14•D for all the passes, the pattern of change in the first upper end processing mode and the first lower end processing mode is 3•D for all the passes, and the pattern of change in the second upper end processing mode and the second lower end processing mode is 6•D for all the passes. Consequently, the first intermediate processing mode and the second intermediate processing mode are different from any of the other modes in terms of their pattern of change in the carry amount F, and thus these processing modes are different from the other processing modes. On the other hand, the first upper end processing mode and the first lower end processing mode both exhibit a pattern of change in the carry amount F of 3•D for all of the passes, and thus they are not different from one another as regards the print processing in the carrying operations. However, as regards the print processing of their dot forming operations, they are different from one another and thus they can be regarded as different processing modes. In other words, the pattern of change in the nozzles that are used in the dot forming operations (passes) in the first upper end processing mode is a pattern in which the nozzles #1 to #3 are used in the first through fourth passes, and the nozzles that are used is increased by one in the order of #4, #5, #6, and #7 each time the pass number increases in the fifth through eighth passes. In contrast, the pattern of change in the first lower end processing mode is a pattern in which the nozzles that are used is decreased by one in the order of #1, #2, #3, and #4 in the first through fourth passes, and in the fifth through eighth passes the nozzles #5 to #7 are used. Consequently, the first upper end processing mode and the first lower end processing mode are different from one another in terms of the nozzle change pattern, and thus, they are different from one another in terms of print processing of the dot forming operations. Due to this, these processing modes are different from one another. Likewise, the second upper end processing mode and the second lower end processing mode both have a carry amount change pattern of 6•D for all of the passes, and thus they are not different from one another in terms of the print processing of the carrying operations. However, as regards the print processing of their dot forming operations, they are different from one another and thus they can be regarded as different processing modes. In other words, the pattern of change in the nozzles that are used in the dot forming operations (passes) in the second upper end processing mode is a pattern in which the nozzles #1 to #3 are used in the first through second passes, and the nozzles that are used is increased by two at a time in the order of #4, #5, #6, and #7 each time the pass number increases in the third through fourth passes. In contrast, the pattern of change in the second lower end processing mode is a pattern in which #3 to #7 are used in the first pass and the nozzles #5 to #7 are used in the second through third passes. Consequently, the second upper end processing mode and the second lower end processing mode are different from one another in terms of the nozzle change pattern, that is, they are different from one another in terms of their print processing of the dot forming operations. Due to this, these processing modes are different from one another. The processing modes were described above using specific examples. However, because the print region A is the only region that contributes to image formation, the raster line numbers are reassigned for only the print region A in the following description. In other words, as shown in the right diagrams of FIG. 21A to FIG. 24C, the uppermost raster line in the print region A is called the first raster line r1, and thereafter heading toward the lower end in the drawings the raster lines are the second raster line r2, the third raster line r3, and so on. ===Regarding the Reason Why Darkness Nonuniformaties Occur in an Image=== Darkness nonuniformaties that occur in a multicolor image that is printed using CMYK inks are generally due to darkness nonuniformaties that occur in each of those ink colors. For this reason, the method that is normally adopted is a method for inhibiting darkness nonuniformaties in images printed in multiple colors by separately inhibiting darkness nonuniformities in each of the ink colors. Accordingly, the following is a description of how darkness nonuniformaties occur in images printed in a single color. FIG. 25A is a diagram for describing darkness nonuniformaties that occur in an image that is printed in a single color, these being darkness nonuniformaties that occur in the carrying direction of the paper S. Further, FIG. 25B is a diagram for describing the darkness nonuniformaties that occur in the carriage movement direction. These diagrams show the darkness nonuniformaties in an image that has been printed in one of the ink colors from CMYK, for example black ink. The darkness nonuniformaties in the carrying direction that are illustrated in FIG. 25A appear as bands parallel to the carriage movement direction (for convenience, these are also referred to as “horizontal bands”). These darkness nonuniformaties in horizontal bands for example occur due to discrepancies in the ink ejection amount between nozzles, but they can also occur due to discrepancies in the processing precision of the nozzles. That is, variation in the direction of travel of the ink that is ejected from the nozzles occurs due to discrepancies in the processing precision of the nozzles. Due to this variation in the travel direction, the positions of the dots that are formed by the ink that lands on the paper S are deviated in the carrying direction from the target formation positions. In such a case, the positions where the raster lines r made of these dots are necessarily also deviated in the carrying direction from their target formation positions, and thus the spacing between adjacent raster lines r in the carrying direction becomes periodically wide or narrow. When viewed macroscopically, these appear as darkness nonuniformaties in horizontal bands. In other words, adjacent raster lines r with a relatively wide spacing between them macroscopically appear light, whereas raster lines r with a relatively narrow spacing between them macroscopically appear dark. The darkness nonuniformaties in the carriage movement direction that are shown in FIG. 25B appear as bands parallel to the direction that intersects the carriage movement direction, that is, to the carrying direction (for convenience, these are also referred to as “vertical bands”). These darkness nonuniformaties in vertical bands for example occur due to the mechanism constituting the printer 1, such as vibration of the carriage 31 as it moves. In other words, due to vibration of the carriage 31 the recording head 41 also is tilted, and the ink that is ejected in this tilted state travels deviated from the standard direction. Due to this deviation in travel direction, the positions of the dots that are formed by the ink that lands on the paper S are shifted in the carriage movement direction with respect to the target formation positions. It should be noted that these factors causing darkness nonuniformaties also apply to the other ink colors as well. As long as even one color among the colors CMYK has this tendency, darkness nonuniformities will appear in an image printed in multiple colors. <Regarding the Method for Inhibiting Darkness Nonuniformities According to a Reference Example> The method of a reference example for inhibiting darkness nonuniformities is described. In the method of this reference example, first, all of the nozzles of the head 41 are used to print a correction pattern for correcting the darkness. That is, ink is intermittently ejected from all of the nozzles as the nozzles move in the carriage movement direction, to thereby print a correction pattern. As regards the raster lines making up the correction pattern that is printed in this manner, the order of the nozzles forming the raster lines matches the order of the nozzles in the nozzle rows. Here, FIG. 26 is a diagram that schematically shows the relationship between the nozzles and the correction pattern that has been printed through this reference example method. As shown in the diagram, the raster line rn positioned on the uppermost end of the correction pattern that is printed on the paper S is formed by nozzle #1. Then, the raster line r(n+1) positioned second from the uppermost end is formed by nozzle #2, and the raster line r(n+2) positioned third is formed by nozzle #3. Likewise thereafter, the raster line r(n+90) positioned 91st from the uppermost end is formed by nozzle #91, and the (180th) raster line r(n+179) positioned on the lowermost end is formed by nozzle #180. Next, the darkness is measured for each pixel in the correction pattern printed in this manner. Darkness measurement is performed along the carrying direction with respect to one spot in the scanning direction of the correction pattern. In the example of FIG. 26, a position Xn in the carriage movement direction is measured along the carrying direction from the upper end to the lower end of the correction pattern. Then, a correction value is obtained for each nozzle based on the dot darkness that has been measured. With the method of this reference example, there is the problem that it is difficult to increase the correction accuracy. This point is described below. Here, FIG. 27A is a diagram schematically showing the dot measurement positions. Further, FIG. 27B is a diagram that shows the measurement signals that are obtained by measuring at the measurement positions of FIG. 27A. In general, the ink that is ejected from the nozzles expands in a substantially circular fashion. As shown in these drawings, if such dots are measured, there would be a difference in the measured darkness, even if the same dot is measured, depending on the spot where the dot is measured. In other words, as shown in the left diagram of FIG. 27A, if measurements are taken along a straight line L1 that passes through the center of the dots, then as shown in the upper stage of FIG. 27B, the duty ratio of the detection signal DS1 is greatest, resulting in the highest measurement darkness. Then, as shown in the center and right diagrams of FIG. 27A, when the dots are measured along the straight lines L2 and L3, which are parallel to the straight line L1 and are positioned outward in the radial direction of the dots from the straight line L1, then as shown in the middle stage and the lower stage of FIG. 27B, the duty ratios of the detection signals DS2 and DS3 are smaller than that of the detection signal DS1, which was measured along the straight line L1 passing through the center of the dots, resulting in a lower measurement darkness. In this case, the measured darkness becomes lower as the straight lines L2 and L3, which show the measured position, move away from the straight line L1, which passes through the center of the dots. Thus, with the method of this reference example the darkness that is obtained differs depending on where in the dot the darkness is measured. For this reason, there is the problem that it is difficult to accurately obtain correction values. Further, with this method it is assumed that all of the dots are formed at the same size in the correction pattern. Thus, it is difficult to adopt this method for a halftone correction pattern that has been recorded by thinning out the dots (for convenience, this is referred to as “halftone correction pattern”). Here, FIG. 28A is a diagram describing darkness measurement of a halftone correction pattern, and FIG. 28B is a diagram for describing the detection signals that are obtained through the darkness measurements of FIG. 28A. As shown in FIG. 28A, the print darkness of the halftone correction pattern is lowered by thinning out the dots that are formed. Thus, the detection signal DS11 that is obtained by measuring the darkness of the dots (raster lines) along a straight line L11 that is parallel with the carrying direction does not include a pulse at the temporal point corresponding to the pixel P1 because a dot is not formed in the pixel P1. Thus, it is difficult to obtain a correction value for the raster line rn to which the pixel P1 belongs. It should be noted that in this case, pulses PS2 and PS3 are obtained because dots DT2 and DT3 are formed in the pixels P2 and P3, respectively. Correction values can be obtained for the raster lines r(n+1) and r(n+2) to which the pixels P2 and P3 belong using these pulses PS2 and PS3. Further, the detection signal DS12 that is obtained by measuring the dots along the straight line L12 does not include a pulse at the temporal point corresponding to the pixel P4 because a dot is not formed in the pixel P4. Thus, it is difficult to obtain a correction value for the raster line r(n+1) to which the pixel P4 belongs. Furthermore, this method does not take into consideration the combination of nozzles that form adjacent raster lines r. In other words, darkness nonuniformaties that occur in the carrying direction and extend in the carriage movement direction (horizontal band-shaped nonuniformaties; see FIG. 25A) may also occur due to the combination of the nozzles forming adjacent raster lines r. Say for example that a particular nozzle #na has the characteristic of ejecting ink toward the upper-end side of the paper S, and a separate nozzle #nb has the characteristic of ejecting ink toward the lower-end side of the paper S. In this case, if a raster line r is formed by the nozzle #nb next to (in a position adjacent on the lower-end side to) a raster line r that is formed by the nozzle #na, then these raster lines will be formed at a spacing that is wider in the carrying direction than the normal spacing. An image that macroscopically is lighter in darkness than normal occurs as a result. Conversely, if a raster line r is formed by the nozzle #na next to a raster line r that is formed by the nozzle #nb, then these raster lines will be formed at a spacing that is narrower in the carrying direction than the normal spacing. An image that macroscopically has a darker darkness than normal occurs as a result. In images that are printed through interlacing, the order of the nozzles that form the raster lines making up the image does not always match the order of the nozzles in the nozzle rows. That is to say, there are cases where the combination of nozzles forming adjacent raster lines may change. Because this combination of nozzles changes depending on the processing modes described above, the correction values that are obtained through the reference example method may not be effective even if they are used when printing in the processing modes. Additionally, with this method, the pixels to be measured in the raster lines making up the correction pattern are a single pixel out of the plurality of pixels making up a single line. Thus, it is difficult to correct darkness nonuniformities in the carriage movement direction (vertical band-shaped darkness nonuniformities) shown in FIG. 25B. ===Method According to the Present Embodiment for Printing an Image in which Darkness Nonuniformities Have Been Inhibited=== <Main Features of Printing Method of Present Embodiment> Taking the above matters into consideration, in the present embodiment, the darkness of each raster line is measured with respect to a printed test pattern to obtain a correction value for each raster line. Here, the darkness of a plurality of pixels positioned on the same raster line is measured and correction values are obtained based on the measured darkness. For example, a correction value is obtained from the average value of the darkness of the plurality of pixels that is measured. Then, the dots of the corresponding raster line are formed in the dot forming operation such that the darkness becomes the darkness corrected by the correction amount. Thus, discrepancies in darkness due to differences in the positions where the dots are measured are cancelled, thereby effectively inhibiting darkness nonuniformaties in the image. Further, in the present embodiment, the correction pattern is printed with the combination of nozzles that are used when the actual printing is performed. For example, if the actual printing is performed using interlacing, then the correction pattern also is printed using interlacing. Further, if there are a plurality of processing modes, then printing is performed through each processing mode. By adopting this method, correction values are obtained also taking into consideration the combination of the nozzles that are used, and thus, darkness discrepancies caused by differences in the combination of nozzles are also corrected. Additionally, in this embodiment, an “other correction value” for correcting the darkness in the carriage movement direction of the image is set for each pixel arranged in the movement direction. Then, in the dot forming operations the dots of the corresponding line are formed so that the darkness becomes the darkness corrected based on both the correction value and the other correction value. Thus, darkness nonuniformities in the carriage movement direction in the image also are inhibited, allowing darkness nonuniformities in the image to be effectively inhibited. Further, the other correction values are obtained by printing an “other correction pattern” and then obtaining the other correction values based on the darkness of the pixels of these correction patterns. In this case, the other correction value is obtained based on the darkness of a plurality of pixels in the same position in the movement direction of the other correction pattern, for example, from the average value thereof. By doing this, darkness discrepancies due to differences in the measurement positions of the dots are cancelled out, allowing darkness nonuniformities in the image to be more effectively inhibited. <Regarding the Method for Printing an Image According to the Present Embodiment> FIG. 29 is a flowchart showing the flow etc. of the processing in the method for printing an image according to the present embodiment. An outline of each process is described below with reference to this flowchart. First, the printer 1 is assembled on the manufacturing line (S110). Next, a worker on the inspection line sets, to the printer 1, correction values for correcting the darkness (S120). The correction values that are obtained here are stored on a memory, more specifically the correction value storage section 63a (see FIG. 8), of the printer 1. Next, the printer 1 is shipped (S130). Then, a user that has purchased the printer 1 performs actual printing of an image, and at the time of this actual printing, the printer 1 prints an image on the paper S while performing darkness correction for each raster line based on the correction values (S140). The method of printing an image according to the present embodiment is achieved by the correction value setting step (step S120) and the actual printing of the image (step S140). Consequently, step S120 and step S140 are described below. It should be noted that for convenience sake, a case in which darkness correction is performed using only the correction values for correcting the darkness in the carrying direction is described first, and a case in which darkness correction is performed combining the other correction values for correcting the darkness in the carriage movement direction will be described later. <Step S120: Setting the Darkness Correction Values for Inhibiting Darkness Nonuniformities> FIG. 30 is a block diagram for describing equipments used in setting the correction values. It should be noted that structural elements that have already been explained are assigned identical reference numerals and thus description thereof is omitted. In this diagram, a computer 1100A is a computer that is disposed on an inspection line, and runs a process correction program 1120. This process correction program can perform a correction value obtaining process. With this correction value obtaining process, a correction value for a target raster line r is obtained based on a data group (for example, 256 tone grayscale data of a predetermined resolution) obtained by a scanner device 100 reading a correction pattern that has been printed on a paper S. It should be noted that the correction value obtaining process is described in greater detail later. Further, an application running on the computer 1100A outputs to the printer driver 1110 image data for printing a correction pattern CP. Then, the printer driver 1110 performs the series of processes from resolution conversion to rasterization, and outputs to the printer 1 the print data for printing the correction pattern CP. FIG. 31 is a conceptual diagram of a recording table that is provided in the memory of the computer 1100A. The recording table is provided separately for each division of ink color and processing mode. The measurement values of the correction pattern CP printed in each division are recorded in the corresponding recording table. It should be noted that this diagram shows recording tables for black (K) for the first upper end processing mode, the first intermediate processing mode, the first lower end processing mode, the second upper end processing mode, the second intermediate processing mode, and the second lower end processing mode, as representative of these recording tables. The measurement values Ca, Cb, and Cc for the three correction patterns CPka, CPkb, and CPkc (described later), which each having a different darkness, and command values Sa, Sb, and Sc corresponding to those measurement values, are recorded in each recording table. Thus, six fields are prepared in this recording table. In the records of the first field and the fourth field from the left of the table are recorded the measurement value Ca, and its command value Sa, for the correction pattern CPka, which has the lightest darkness. Further, in the records of the third field and the sixth field from the left are recorded the measurement value Cb, and its command value Sb, for the correction pattern CPkb, which has the darkest darkness. Likewise, in the records of the second field and the fifth field from the left are recorded the measurement value Cc, and its command value Sc, for the correction pattern CPkc, which has an intermediate darkness. A record number is given to each record, and the measurement values of the small-numbered raster lines in the corresponding correction patterns. CP1, CP2, and CP3 (described later) are successively recorded from the small number records. The number of records that is provided is the number that can correspond to the overall width of the print region A (length in the carrying direction). For the three correction patterns CPka, CPkb, and CPkc, the measurement values Ca, Cb, and Cc and the command values Sa, Sb, and Sc of the same raster line are recorded in a record with the same record number. FIG. 32 is a conceptual diagram of the correction value storage section 63a provided in the memory 63 of the printer 1. As shown in the drawing, correction value tables are prepared in the correction value storage section 63a. Like the recording tables mentioned above, the correction value tables are provided separately for each color ink and processing mode. Consequently, correction values also are prepared for each ink color and each processing mode. This diagram shows the correction value tables for black (K) for the first upper end processing mode, the first intermediate processing mode, the first lower end processing mode, the second upper end processing mode, the second intermediate processing mode, and the second lower end processing mode, as representative correction value tables. These correction value tables each have records for recording a correction value. Each record is assigned a record number, and a correction value calculated based on the measurement values is recorded in the record having the same record number as the record for those measurement values. Further, the number of records that is provided is the number that can correspond to the overall width of the print region A. It should be noted that the procedure for storing correction values in the correction value storage section 63a is described in greater detail later. FIG. 33 is a diagram for describing the scanner device 100 that is communicably connected to the computer 1100A. That is, FIG. 33A is a vertical sectional view of the scanner device 100, and FIG. 33B is a plan view of the scanner device 100. The scanner device 100 is a type of darkness measuring device that optically measures the darkness of the correction patterns CP (see FIG. 35), which are described later. The scanner device 100 is capable of reading an image that has been printed on an original document 101 (for example, a paper S on which a correction pattern has been printed) as a data group in units of pixels, and is provided with an original document bed glass 102 on which the original document 101 is placed, a reading carriage 104 that moves in a predetermined movement direction in opposition to the original document 101 via the original document bed glass 102, and a controller (not shown) for controlling the various sections, such as the reading carriage 104. The reading carriage 104 is provided with an exposure lamp 106 that irradiates light onto the original document 101 and a linear sensor 108 for receiving the light that is reflected by the original document 101 over a predetermined range in a perpendicular direction that is perpendicular to the movement direction. Then, the scanner device 100 reads an image that has been printed on the original document 101 at a predetermined reading resolution by moving the reading carriage 104 in the movement direction while causing the exposure lamp 106 to emit light and receiving the light that is reflected with the linear sensor 108. It should be noted that the dashed line in FIG. 33A indicates the path of the light when image reading. FIG. 34 is a flowchart showing the procedure of step S120 in FIG. 29. The procedure for setting the correction values is described below using this flowchart. This setting procedure includes a step of printing a correction pattern CP (S121), a step of reading the correction pattern CP (S122), a step of measuring the pixel darkness of each raster line (S123), and a step of setting a darkness correction value for each raster line (S124). These steps are described in detail below. (1) Regarding Printing the Correction Pattern CP (S121) First, in step S121, a correction pattern CP is printed on the paper S. Here, a worker on the inspection line communicably connects the printer 1 to a computer 1100A on the inspection line and prints a correction pattern CP using the printer 1. In other words, the worker gives out a command to print a correction pattern CP through a user interface of the computer 1100A. At that time, the print mode and the paper size mode are set through the user interface. Due to this command, the computer 1100A reads the image data of the correction pattern CP that is stored in the memory and performs the above-mentioned processes of resolution conversion, color conversion, halftone processing, and rasterization. The result of this processing is that print data for printing a correction pattern CP are output to the printer 1 from the computer 1100A. Then, the printer 1 prints the correction pattern CP on the paper S according to the print data. It should be noted that the printer 1 that prints the correction pattern CP is the printer 1 for which correction values are to be set. In other words, correction values are set on a printer-by-printer basis. Here, FIG. 35 is a diagram describing an example of the correction pattern CP that is printed. As shown in this drawing, the correction pattern CP of the present embodiment is printed in divisions of ink color, darkness, and processing mode. The print data of the correction pattern CP are data that have been created by performing halftone processing and rasterization with respect to CMYK image data made by directly specifying the gradation value of each of the ink colors CMYK. Then, the gradation values of the pixel data of the CMYK image data are set to the same value for all of the pixels of each band-shaped correction pattern CP formed for each ink color and darkness. Due to this, each correction pattern CP is printed at substantially the same darkness over the entire region in the carrying direction. In principle, the only difference between the correction patterns CP is the ink color. For this reason, hereinafter the black (K) correction pattern CPk is described as a representative correction pattern CP. Further, as mentioned above, darkness nonuniformities in multicolor prints are inhibited for each ink color that is used in that multicolor print, but the method that is used for inhibiting the darkness nonuniformities is the same. For this reason, black (K) shall serve as an example in the following description. In other words, in the following description there are sections that only describe examples for the color black (K), but the same also applies for the other ink colors C, M, and Y as well. The black (K) correction pattern CPk is printed in a band shape that is long in the carrying direction. The print region in the carrying direction extends over the entire region in the carrying direction of the paper S. In other words, it is formed contiguously from the upper end to the lower end of the paper S. Further, the correction pattern CPk is formed such that three band patterns are formed in rows, in the carriage movement direction, parallel to one another. The gradation values of these correction patterns CP can be set freely. However, from the standpoint of actively inhibiting darkness nonuniformities in regions in which darkness nonuniformities occur easily, a gradation value that results in a so-called halftone is selected in the present embodiment. Further, these correction patterns CP have mutually different print darkness. That is, a plurality of types of correction patterns CP each with a different darkness have been prepared. In the present embodiment, there are a correction pattern CPkc that has been set to a gradation value at which darkness nonuniformities occur easily (for convenience, this is referred to as the “reference gradation value”), a correction pattern CPka that has been set to a gradation value that is lower than the reference gradation value (for convenience, this is referred to as the “low-darkness-side gradation value”), and a correction pattern CPkb that has been set to a gradation value that is higher than the reference gradation value (for convenience, this is referred to as the “high-darkness-side gradation value”). Here, the reference gradation value can be the gradation most suited for finding the correction value, and in a case where the gradation value has 256 tones and the ink color is black, it corresponds to a gradation value range from 77 to 128. Further, the gradation value on the low darkness side of the reference gradation value and the gradation value on the high darkness side of the reference gradation value are set such that their center value is the reference gradation value. For example, the low-darkness-side gradation value is set to a gradation value that is about 10% lower than the reference gradation value, and the high-darkness-side gradation value is set to a gradation value that is about 10% higher than the reference gradation value. It should be noted that the reason for using a plurality of types of correction patterns CP having different darkness is described later. The correction pattern CPk is printed for each processing mode, and in the example of the drawing, one of the correction patterns CP1, CP2, and CP3, which differ in processing modes, is printed in one of the three regions partitioned in the carrying direction. Here, it is preferable that the relationship dictating which correction pattern CP1, CP2, and CP3 is printed in which of these partitioned regions matches that relationship for actual printing. For example, taking the first upper end processing mode, the first intermediate processing mode, and the first lower end processing mode as examples, if the first processing mode is selected at the time of actual printing, then the upper end of the paper S is actually printed through the first upper end processing mode, the intermediate portion of the paper S is actually printed through the first intermediate processing mode, and the lower end of the paper S is actually printed through the first lower end processing mode. For this reason, in the correction pattern CPk, the correction pattern CP that is printed through the first upper end processing mode is printed to the region on the upper-end side of the paper S (hereinafter, this is referred to as the “first upper end correction pattern CP1). Likewise, the correction pattern CP that is printed through the first intermediate processing mode is printed to the region of the intermediate portion of the paper S (hereinafter this is referred to as the “first intermediate correction pattern CP2”), and the correction pattern CP that is printed through the lower end processing mode is printed to the region on the lower-end side of the paper S (hereinafter, referred to as the “first lower end correction pattern CP3”). By doing this, the carrying operations and the dot forming operations that are the same as those of the actual printing can be faithfully reproduced when printing the correction patterns CP1, CP2, and CP3. As a result, the accuracy of darkness correction using the correction values obtained based on these correction patterns CP1, CP2, and CP3 is increased, allowing darkness nonuniformities to be reliably inhibited. The reason why a plurality of types of correction patterns CP each having a different darkness are used is described below. First, the problems that arise when there is a single type of correction pattern CP having a single darkness for each color are described. When there is only a single type of correction pattern CP having a single darkness, then normally the raster lines that make up that correction pattern CP will have a target darkness that is the average value obtained by averaging the darkness. Then, the correction value is set such that the darkness of a target raster line becomes this target darkness. For example, let us assume that a gradation value C is the measured darkness value of a target raster line, a gradation value M is the average value of the measured darkness values of the raster lines, and ΔC is the difference between the measured value (gradation value C) and the average value (gradation value M). In this case, a correction value H for the darkness of each raster line can be found through the Formula 1 below. correction value H = Δ C / M = ( M - C ) / M ( Formula 1 ) Then, the pixel data of the image data are corrected using this correction value H, thereby correcting the darkness of the raster line. Here, a raster line whose correction value H is ΔC/M will have a darkness measurement value C that is changed by ΔC (=H×M) due to correction, and can be expected to be the target value (average value M). In order for it to change in this way, when reading the level data corresponding to the gradation value M of the pixel data from the dot creation ratio table (see FIG. 4), first the correction amount ΔC is calculated by multiplying the gradation value M by the correction value H (=ΔC/M). Next, the level data of the gradation value shifted from the gradation value M by the correction value ΔC is read. Then, the size of the dot that should be formed is determined based on this level data and the dither matrix (see FIG. 5). At this time, the size of the dot that is formed changes by the amount that the level data has changed by the difference ΔC, and thus the measurement value C of the darkness of the raster line is corrected. However, just changing the gradation value M for reading the level data by the difference ΔC is no guarantee that the measurement value of the darkness of the raster line that is printed will be reliably changed by the difference ΔC and become the target value (gradation value M). That is, with the correction value H, the measurement value C can be brought closer to the target value M but it might not necessarily bring it close enough that they substantially match. Consequently, with this method, one was forced to repeatedly perform printing of the correction pattern CP and measurement of its darkness while changing the correction value H until the most suitable correction value H is obtained, that is, until the measurement value (gradation value C) becomes the target value (average value M). Thus, this task required a large amount of work. On the other hand, in this embodiment, three different correction patterns CP (such as CPka, CPkb, and CPkc), each having a different darkness due to changing the darkness command value, are printed, three information pairs each having a measurement value and a command value as a pair are obtained, and using these three information pairs that are obtained, the correction value H is obtained. For example, by performing primary interpolation using the three information pairs, a correction value H whose measurement value becomes the target value is obtained directly. By doing this, when obtaining the correction value H, it is not necessary to perform the above-described burdensome repeated task, allowing the correction value H to be obtained efficiently. It should be noted that the procedure for obtaining the correction value using the correction patterns CP is described in greater detail later. Further, in the present embodiment, vertical reference ruled lines RL1 extending in the carrying direction (this corresponds to the “intersecting-side reference ruled line” in the claims) are formed together with the correction patterns CP. The vertical reference ruled lines RL1 are used for correcting image data obtained by reading with the scanner device 100. In the example of FIG. 35, two vertical reference ruled lines RL1 are formed. One of these is formed between the cyan correction pattern CPc and the left edge of the paper S (that is, in the left edge region of the paper S), parallel to the correction pattern CPc. The other one is formed between the black correction pattern CPk and the right edge of the paper S (that is, the right edge region of the paper S), parallel to the correction pattern CPk. The vertical reference ruled lines RL1 can be printed in ink of any color, but it is preferable that the ink is a color that has a high contrast with respect to the base color of the paper S. For example, if the base color of the paper S is white, then it is preferable that the vertical reference ruled lines RL1 are printed in black ink. This is because the higher the contrast with the base color, the more accurately the vertical reference ruled lines RL1 can be read by the scanner device 100. It should be noted that the method of using the vertical reference ruled lines RL1 is described along with the explanation of reading the correction patterns CP. Additionally, in the present embodiment, index markers IM for recognizing the upper end of the paper S are printed in the corner portions of the paper upper end. The index markers IM are used when identifying the upper end and the lower end of an image, as regards the image data obtained by reading with the scanner device 100. In other words, the top and bottom of an image that has been read is determined by the computer 1100A based on these index markers IM when reading the darkness of the correction patterns CP. That is, the computer 1100A determines that the side on which the index markers IM are printed is the upper-end side, and that the side on which the index markers IM are not printed is the lower-end side. Thus, when reading the correction patterns CP, even if a worker on the inspection line mistakes the upper and lower sides of the correction pattern CP when placing the paper S on the original document bed, measurement can be performed without problem. (2) Reading the Correction Patterns CP (Step S122) Next, the correction patterns CP that have been printed are read by the scanner device 100. In step S122, first a worker on the inspection line places the paper S on which the correction patterns CP have been printed onto the original document bed. At this time, he/she places the paper S such that, as shown in FIG. 33B, the raster line direction of the correction patterns CP (CPc to CPk) and the perpendicular direction of the scanner device 100 (that is, the direction in which the linear sensor 108 is arranged) are the same direction. Once the paper S has been placed, the worker sets the reading conditions through the user interface of the computer 1100A and then gives out a command to initiate reading. Here, it is preferable that the reading resolution in the movement direction of the reading carriage 104 is several integer multiples narrower than the pitch of the raster lines. In this way, the measured values of the darkness that is read and the raster lines can be correlated easily, allowing the measurement accuracy to be increased. When the command to initiate reading is received, the controller (not shown) of the scanner device 100 controls the reading carriage 104, for example, to read the correction patterns CP that have been printed on the paper S and obtain data groups in units of pixels. The data groups that are obtained are transferred to the memory of the computer 1100A. Here, FIG. 36 is a diagram schematically explaining how the correction patterns CP are read by the linear sensor 108. Further, FIG. 37A is a diagram for schematically describing the positions where the dots are read by the light receiving elements provided in the linear sensor 108, FIG. 37B is a diagram for describing the detection signals (pulses) when reading is performed at the positions of FIG. 37A, and FIG. 37C is a diagram for describing the difference in pixel darkness that is recognized from the pulses of FIG. 37B. When the paper S has been placed and the image is read, then, as shown in FIG. 36, the linear sensor 108 moved from the upper end to the lower end, or conversely, from the lower end to the upper end, of the paper S, and successively reads the darkness of the dots making up the correction patterns CP. At this time, the light-receiving elements of the linear sensor 108 move along the path shown by the dotted arrows in the drawing, that is, in a path along the carrying direction. In this case, the pitch at which adjacent light-receiving elements are arranged and the pitch at which the dots of the correction patterns CP are formed do not necessarily match. Thus, as shown in FIG. 37A, the positions of intersection between the path of movement of the light-receiving elements and the dots are not always the same. Due to this difference in intersection position, the detection times of the detection signals (pulses) become different. For example, looking at the dot DT11 positioned on the left edge of FIG. 37A, the light-receiving element corresponding to this dot DT11 passes over the right side edge portion of the dot DT11 as is clear from the movement path L21. For this reason, that light-receiving element starts detection of the dot DT11 at a time t11a and ends detection at a time t11b. The time duration of the detection signal PS11 consequently becomes T11. On the other hand, looking at the dot DT15 fifth from the left, the light-receiving element corresponding to the dot DT15 passes over substantially the center between the left and right of the dot DT15, as is clear from the movement path L25. For this reason, that light-receiving element starts detection of the dot DT15 at a time t15a and ends detection at a time t15b. The time duration of the detection signal PS15 consequently becomes T15, and the time duration of the detection signal is largest when the dot DT15 is detected. Comparing the time duration T15 of the detection signal DT15 and the time duration T11 of the detection signal DT11, the time duration T11 is approximately 70% of the time duration T15. In this case, as FIG. 37C schematically shows, the pixel PX11 to which the dot DT11 lands is determined to have a darkness that is 70% that of the pixel PX15 to which the dot DT15 lands, even though the dot DT11 and the dot DT15 are the same size. The same applies for the other dots DT12 to DT14, DT16, and DT17, and even though the dots are the same size the darkness of the pixels PX12 to PX14, PX16, and PX17 change depending on the position over which the corresponding light-receiving element passes. Consequently, discrepancies occur in the darkness of the pixels PX after reading by the scanner device 100 due to the position where the dots are read, as shown in FIG. 38. Further, the correction patterns CP in the present embodiment are printed in halftone as mentioned above. As can be understood from FIG. 4, with halftone there is a possibility that any one of a small dot, a medium dot, and a large dot will be formed in each pixel PX. From this standpoint there consequently is a possibility that discrepancies will occur in the darkness. From the above it is clear that it is difficult to sufficiently obtain the effect of correction if the darkness of one raster line is represented by a single pixel. Accordingly, with the present embodiment, in the measurement of each raster line that is performed next, the darkness of a plurality of pixels located on the same raster line is measured and the correction value is obtained based on their darkness. (3) Measuring the Darkness of the Correction Patterns CP (Step S123) FIG. 39 is a flowchart showing in detail the procedure of the step S123 in FIG. 34. The computer 1100A executes the procedure of the step S123 under the process correction program. Measurement of the darkness of the correction patterns CP is described below with reference to this flowchart. In step S123a, the computer 1100A first performs correction of the transferred data groups (hereinafter, also referred to as “tilt correction”). Here, FIG. 40 is a diagram schematically describing the tilt correction that is performed in this step. More specifically, the upper stage of this diagram shows the upper end section of the vertical reference ruled line RL1 printed on the upper end section of the paper S, the middle stage shows the intermediate portion of the vertical reference ruled line RL1 printed on an intermediate portion of the paper S, and the lower stage shows the lower end section of the vertical reference ruled line RL1 printed on the lower end section of the paper S. It should be noted that for convenience sake, the vertical reference ruled line RL1 in the drawing is drawn at a thickness of two pixels (see the solid black section in the drawing), and the intermediate positions in the scanning direction are the positions of the ruled line. In tilt correction, the computer 1100A first sets the reference position of the vertical reference ruled line RL1. For example, the computer 1100A obtains the position of the upper end or the lower end, more specifically the position in the scanning direction along the carriage movement direction, and sets the position in the scanning direction that is obtained as the reference position. Next, the computer 1100A reads the position of the vertical reference ruled line RL1 at each raster line, comparing this against the reference position. If the position in the scanning direction of the raster line is deviated from the reference position, then the data of the pixels belonging to that raster line is shifted (moved) by that amount of deviation. As an example, a case in which the position Xn of the vertical reference ruled line RL1 at the first line r1 is regarded as the reference position is described below. In this case, if the position of the vertical reference ruled line RL1 at the n-th raster line is Xn+1, shifted to the right of Xn by one pixel, then the computer 1100A shifts the data of the pixels belonging to the raster line rn to the left by one pixel. Similarly, in the m-th raster line, the position of the vertical reference ruled line RL1 is Xn+2, shifted two pixels to the right of Xn, and thus the computer 1100A shifts the data of the pixels belonging to the raster line rm to the left by two pixels. Then, once this correction has been performed for all of the raster lines making up the correction pattern CP, the procedure advances to step S123b. By performing tilt correction, the shift from the correct position can be corrected, even if the correction pattern CP is read shifted off of the correct position. Then, because the pixel darkness is measured after this shifting has been corrected, the reliability of the correction values and the other correction values can be increased. Further, shifting in the pattern can be automatically corrected through the above image processing. Thus, the processing efficiency can also be improved. It should be noted that in tilt correction, if the difference in the position in the scanning direction between the upper end section and the lower end section of the vertical reference ruled line RL1 is equal to or greater than a predetermined threshold value, then it is possible to suggest that the correction pattern CP is read again because an accurate measurement cannot be performed. In this case, the computer 1100A displays message urging re-reading through the user interface. Next, the computer 1100A measures the darkness of a plurality of pixels located on the same raster line of the correction pattern CP. First, the computer 1100A obtains position information of a first raster line to be measured (S123b). In this embodiment, darkness is measured from the uppermost raster line, and thus a value “1” (Y=1) is obtained as the information on the sub-scanning position. Once the position information of the raster line has been obtained, the computer 1100A obtains position information indicating the main-scanning position of the pixel to be measured (S123c). Here, the position in the main-scanning direction differs depending on the correction pattern CP to be measured. Thus, in this step, X1 (X=X1) is obtained as the information on the main-scanning position. It should be noted that as shown in FIG. 35, the correction patterns CP of this embodiment are band-shape that are long in the vertical direction, and as will be discussed later, the pixel to be measured is moved successively to the right. Thus, it is preferable that the position in the main-scanning direction is set to the position of the left edge of the correction patterns CP. Once the information Y on the sub-scanning position and the information X on the main-scanning position have been obtained, the darkness of the pixel specified by these positions is obtained (S123d). Once the darkness of this pixel has been obtained, the value of the X coordinate is increased by 1 (i.e., X=X+1) (S123e). That is, the pixel to be measured is reset to the pixel adjacent to its right in the main-scanning direction. Then, it is determined whether or not the new X coordinate that is obtained by adding 1 is greater than a threshold value (X1+n) (S123f). Here, if the X coordinate does not exceed the threshold value (X1+n), then the procedure is returned to step S123d and the darkness of the pixel specified by the new X coordinate is obtained. It should be noted that the threshold value is defined as the number of pixels whose darkness is to be obtained (corresponds to n above). This pixel number can be set to any value, but preferably it is set to within a range from several tens to several hundreds of pixels, and more preferable it is set to within the range of 50 to 200. In the present embodiment, it has been set to 50. Thereafter, the procedure of the steps S123d to S123f is repeated, successively obtaining the darkness of the pixels. If it is determined in step S123f that the X coordinate has exceeded the threshold value (X1+n), that is, if the darkness for the last pixel to be measured in that raster line has been measured, then the procedure is advanced to step S123g, and an average darkness value of the n pieces of pixels that have been measured is found. Once the average darkness value has been obtained, the procedure is advanced to step S123h, and the average darkness value that has been obtained is recorded in the corresponding record of the recording table as the darkness for that raster line. For example, if the average darkness value has been obtained for the first raster line in the sub-scanning direction, then that average darkness value is recorded in the first record. Once the average darkness value has been recorded, the above procedure is performed for the next raster line. That is, in step S123i the value of the Y coordinate is increased by 1 (i.e., Y=Y+1). In other words, the raster line to be measured is reset to a raster line that is positioned adjacent on the downstream side in the carrying direction. It is then determined whether or not the new Y coordinate that has been obtained by adding 1 exceeds the last sub-scanning position (S123j). Here, if the Y coordinate does not exceed the last sub-scanning position, then the procedure is returned to step S123c and the darkness of the raster line specified by the new Y coordinate is obtained (S123c to S123h). On the other hand, if the Y coordinate does exceed the last sub-scanning position, then darkness measurement for that correction pattern CP is ended, and darkness measurement for the next correction pattern CP is performed. FIG. 41 shows an example of the measured darkness values of a correction pattern CP obtained in this manner. Here, FIG. 41A is a diagram showing the result of measuring the darkness of specific pixels at the same position in the carriage movement direction, along a line parallel to the carrying direction (hereinafter, also referred to as “virtual line”). Further, FIG. 41B shows the measurement results obtained by changing the position of the virtual line and the average darkness obtained from these measurement results. In these diagrams, the horizontal axis denotes the raster line number and the vertical axis denotes the measured darkness value. In FIG. 41B the thin lines show the measured darkness values for each virtual line, and the thick line shows the average darkness of the pixels belonging to the same raster line. From these drawings, it is clear that the measured darkness fluctuates for each pixel, even for pixels that are on the same raster line. Consequently, by taking the average value of a plurality of pixels on the same raster line it is possible to obtain an accurate darkness for each raster line. It should be noted that with the procedure described above, the plurality of pixels whose darkness is measured are adjacent to one another. This is in consideration of the possibility that periodic darkness nonuniformities may occur in the carriage movement direction (the main-scanning direction). In other words, adopting this method allows reliable prevention of the problem of, in a case where darkness nonuniformities have periodically occurred in the carriage movement direction, selectively measuring only those spots where darkness nonuniformities have occurred. As a result, the reliability of the correction values and the other correction values can be increased. (4) Setting the Darkness Correction Value for Each Raster Line (Step S124) Next, the computer 1100A sets the correction value of the darkness for each raster line. Here, the computer 1100A calculates the correction values for the darkness based on the measured values that have been recorded in the records of the recording tables, and sets the correction values in the correction value storage section 63a of the printer 1 (see FIG. 32). As mentioned above, the correction value storage section 63a has records to which the correction values are recorded. Each record is assigned a record number, and the correction value that has been calculated based on the measured value is recorded to the record with the same record number as the record with that measured value. For example, the correction values that have been calculated based on the corresponding measured values of the recording table are recorded in the records of the correction value recording section allocated for the first upper end processing mode. Consequently, correction values corresponding to the upper-end-only region and the upper-end/intermediate mixed region are recorded in this correction value recording section. These correction values are obtained in the format of a correction ratio indicating the ratio of correction with respect to the gradation value of the darkness. More specifically, this is performed following the flowchart of FIG. 42. First, the computer 1100A calculates the correction value H (S124a). Here, the correction value H is calculated by performing primary interpolation using the three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc) of the pairing between the command values Sa, Sb, and Sc and the measurement values Ca, Cb, and Cc recorded in the records of the recording tables, and that correction value H is set in the correction value table. In this processing the correction value is obtained through primary interpolation, and thus the processing can be simplified, allowing the work efficiency to be increased. Further, in this processing, three information pairs are used, and thus the correction value H can be calculated with high accuracy. In other words, in general, the slope is different among straight lines used in primary interpolation in a range where the darkness is either higher or lower than the reference. Even in this case, with this method, the two information pairs (Sb, Cb) and (Sc, Cc) can be used to perform primary interpolation for the range in which the darkness is higher than the reference darkness, and the two information pairs (Sa, Ca) and (Sc, Cc) can be used to perform primary interpolation for the range in which the darkness is lower than the reference darkness. Thus, the correction value H can be calculated accurately even when the slope of the straight lines obtained used in primary interpolation is different. FIG. 43 is a graph for describing primary interpolation performed using these three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc). In FIG. 43, the horizontal axis of the graph is the gradation value of black (K) serving as the command value S, and the vertical axis is the gradation value of the grayscale serving as the measurement value C. The coordinates of the points on the graph are indicated by (S, C). As shown in this diagram, the three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc) are each expressed on the graph by point A having the coordinates (Sa, Ca), point B at (Sb, Cb), and point C at (Sc, Cc). The straight line BC connecting the points B and C shows the relationship between the change in command value S and the change in measurement value C in a range where the darkness is higher than the reference darkness. Further, the straight line AC connecting the points A and C shows the relationship between the change in command value S and the change in measurement value C in a range where the darkness is lower than the reference darkness. Then, a value So of the command value S at which the measurement value C becomes the target value Ss1 is read from the graph made of these two lines AC and BC to determine the correction value H. For example, first the value So of the command value S at which the measurement value C is the target value Ss1 is read from these lines AC and BC. The value So is the command value S at which the measurement value C of the darkness is the target value Ss1. Here, even though normally (that is, if correction is unnecessary) the target value Ss1 should be obtained at the measurement value C if the command value S is set to the reference value Ss, the measurement value C does not become the target value Ss1 unless the command value S is set to So. It is clear from this that the deviation So-Ss between the value So and the value Ss will become the correction amount ΔS. It should be noted that the correction value H is given in the form of a correction ratio, and thus the value obtained by dividing the correction amount ΔS by the reference value Ss is calculated as the correction value (correction value H=ΔS/Ss). Incidentally, the following is the correction value H when expressed as a formula. First, the line AC on the lower darkness side can be expressed by Formula 2 below. C=[(Ca−Cc)/Sa−Sc]]·(S−Sa)+Ca Formula 2 If Formula 2 is solved for the command value S and the target value Ss1 is substituted for the measurement value C, then the command value So at which the measurement value C becomes the target value Ss1 can be expressed by Formula 3 below. So=(Ss1−Ca)/[(Ca−Cc)/(Sa−Sc)]+Sa Formula 3 Similarly, the line BC on the higher darkness side can be expressed by Formula 4 below. C=[(Cc−Cb)/Sc−Sb]]·(S−Sc)+Cc Formula 4 If Formula 4 is solved for the command value S and the target value Ss1 is substituted for the measurement value C, then the command value So at which the measurement value C becomes the target value Ss1 can be expressed by Formula 5 below. So=(Ss1−Cc)/[(Cc−Cb)/(Sc−Sb)]+Sc Formula 5 On the other hand, the correction amount ΔS of the command value S is expressed by Formula 6, and the correction value is expressed by Formula 7. ΔS=So−Ss Formula 6 H=ΔS/Ss=(So−Ss)/Ss Formula 7 Consequently, Formulas 3, 5, and 7 are the formulas for finding the correction value H, and by substituting concrete values for Ca, Cb, Cc, Sa, Sb, Sc, Ss, and Ss1 in these formulas, it is possible to find the correction value H. A program for executing the computations of these formulas is stored on a memory provided in the computer 1100A on the inspection line. The correction value H that is obtained in this manner is stored in the correction value table shown in FIG. 32 (S124b). In other words, the computer 1100A reads the three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc) from the same record of the recording table and substitutes these into Formula 3, Formula 5, and Formula 7 to calculate the correction value H, and then records the calculated correction value to the record of the same record number in the correction value table. Thus, by using this correction value H to perform darkness correction, which is discussed later, discrepancies in the darkness between each raster line can be made small for each ink color and each processing mode, thus allowing darkness nonuniformities to be inhibited. <Step S140: Actual Printing of the Image While Performing Darkness Correction for Each Raster Line> The printer 1 in which the darkness correction values are set as above is shipped and operated by a user. In other words, the actual printing is performed by the user. In the actual printing, the printer driver 1110 and the printer 1 work in cooperation to perform darkness correction for each raster line and execute printing in which darkness nonuniformities are inhibited. Here, the printer driver 1110 references the correction values stored in the correction value table and corrects the pixel data such that it becomes the darkness corrected based on this correction value. That is, the printer driver 1110 changes the 2-bit pixel data in accordance with the correction value when converting the RGB image data into print data. It then outputs the print data based on the corrected image data to the printer 1. The printer 1 forms the dots of the corresponding raster line based on those print data. The print procedure is described in greater detail below. (1) Regarding the Darkness Correction Procedure: FIG. 44 is a flowchart showing the procedure for correcting the darkness of each raster line in step S140 of FIG. 29. Hereinafter, the darkness correction procedure is described with reference to this flowchart. In this procedure, first the printer driver 1110 obtains information on the “margin format mode,” “image quality mode,” and “paper size mode” for the actual printing (step S141). Next the printer driver 1110 successively performs resolution conversion (step S142), color conversion (step S143), halftone processing (step S144), and rasterization (step S145). Step S141: First, the user communicably connects the printer 1 that he/she has purchased to his/her computer 1100, establishing the printing system described in FIG. 1. The user then inputs the margin format mode, the image quality mode, and the paper size mode through the user interface screen of the printer driver 1110 in the computer 1100. Due to this input, the printer driver 1110 obtains information on these modes, for example. For example, “fine” is input as the image quality mode, “borderless” is input as the margin format mode, and “first size,” that is, the paper size whose size in the carrying direction is 110•D, is input as the paper size mode. Step S142: Next, the printer driver 1110 performs resolution conversion with respect to the RGB image data that have been output from the application program 1104. That is, it converts the resolution of the RGB image data to the print resolution corresponding to the image quality mode that has been input. The printer driver 1110 then suitably processes the RGB image data by trimming, for example, to adjust the number of pixels in the RGB image data so that it matches the number of dots in the print region A corresponding to the paper size and margin format mode that have been designated. Step S143: Next, the printer driver 1110 executes color conversion to convert the RGB image data into CMYK image data. As mentioned above, the CMYK image data include C image data, M image data, Y image data, and K image data, and these C, M, Y, and K image data are each made of 121 rows of pixel data. Step S144: Next, the printer driver 1110 performs halftone processing. Halftone processing is for converting the gradation values of 256 grades indicated by the pixel data in the C, M, Y, and K image data into gradation values of four grades. It should be noted that the pixel data of these four gradation values are 2-bit data indicating “no dot formation,” “small dot formation,” “medium dot formation,” and “large dot formation.” Then, in this embodiment, darkness correction is performed for each raster line during halftone processing. In other words, the processing for converting each pixel data of the image data from a gradation value of 256 grades to one of four grades is performed while correcting the pixel data by the amount of the correction value. Darkness correction is performed for each of the C, M, Y, and K image data based on the correction value table provided for each ink color, but here black (K) image data are described to represent these image data. In halftone processing, the printer driver 1110 specifies the processing mode to be used and executes darkness correction at the correction value corresponding to that specified processing mode. Thus, the printer driver 1110 first references the first reference table (FIG. 19) using the margin format mode and the image quality mode as guides to obtain the corresponding print mode. The printer driver 1110 then references the second reference table (FIG. 20) using the print mode as a guide to specify the processing mode to be used during actual printing of the image. If a single processing mode is specified, then the correction value table for that processing mode is used to correct the pixel data rows in the K image data. On the other hand, if a plurality of processing modes have been specified, then the regions that are to be printed by each printing mode are specified in accordance with the paper size mode. Then, the correction value table for each processing mode is used to correct the image data rows corresponding to the regions to be printed by that processing mode. It should be noted that the information on the regions that are printed by the processing modes is recorded in a region determination table. The region determination table is stored on the memory in the computer 1100, and the printer driver 1110 references this region determination table to specify the region that is printed by each processing mode. For example, as shown in FIG. 21A, the upper-end-only region and the upper-end/intermediate mixed region that are printed by the first upper end processing mode are formed in a fixed number of eight passes as discussed above, and thus it is known in advance that the region will have 40 raster lines from the uppermost end of the print region A toward the lower-end side. Consequently, “region from uppermost end of print region A to the 40th raster line” is recorded in the region determination table to correspond to the first upper end processing mode. Similarly, as shown in FIG. 21B, the intermediate/lower-end mixed region and the lower-end-only region printed through the first lower end processing mode are formed in a fixed number of eight passes as discussed above, and thus it is known in advance that the region will have 36 raster lines from the lowermost end of the print region A toward the upper-end side. Consequently, “region from lowermost end of print region A to the 36th raster line toward the upper-end side thereof” is recorded in the region determination table to correspond to the first lower end processing mode. Further, as shown in FIG. 21A and FIG. 21B, the intermediate-only region that is printed through the first intermediate processing mode only is the region that continues toward the lower-end side from the region that is printed by the first upper end processing mode, and is also the region that continues toward the upper-end side from the region that is printed by the first lower end processing mode. Thus, the intermediate-only region is known in advance to be the region that is sandwiched by the 41st raster line toward the lower end from the uppermost end of the print region A and the 37th raster line toward the upper end from the lowermost end of the print region A. Consequently, “region sandwiched by the 41st raster line toward the lower end from the uppermost end of the print region A and the 37th raster line toward the upper end from the lowermost end of A” is recorded in the region determination table to correspond to the first intermediate processing mode. In this example, the modes are “borderless” and “fine,” and thus the printer driver 1110 references the first and second reference tables shown in FIG. 19 and FIG. 20 and specifies “first print mode” as the print mode, and thus the three corresponding processing modes of first upper end processing mode, first intermediate processing mode, and first lower end processing mode are specified as the processing modes for the actual printing. Further, because the paper size mode is “first size” the print region A in the actual printing is 121•D in the carrying direction, and as discussed above, because there are three processing modes, the regions that are printed by the respective processing modes are specified with reference to the region determination table, and the pixel data rows corresponding to the respective regions are corrected. For example, the upper-end-only region and the upper-end/intermediate mixed region that are printed through the first upper end processing mode are specified from the region determination table as the region from r1 to r40 in the print region of r1 to r121. The data of the raster lines of the region r1 to r40 are the pixel data rows from the first row to the 40th row of the K image data. On the other hand, the correction values corresponding to the upper-end-only region and the upper-end/intermediate mixed region are recorded in the first through 40th records in the correction value table for the upper end processing mode. Consequently, the correction values of the first through 40th records of the correction value table for the first upper end processing mode are successively correlated to the first through 40th pixel data rows while the pixel data making up each pixel data row are corrected. Similarly, the intermediate/lower-end mixed region and the lower-end-only region that are printed through the first lower end processing mode are specified as the region from r86 to r121 in the print region of r1 to r121 based on the region determination table. The data of the raster lines of the region r86 to r121 are the pixel data rows from the 86th row to the 121st row of the K image data. On the other hand, the correction values corresponding to the intermediate/lower-end mixed region and the lower-end-only region are recorded in the first through 36th records of the correction value table for the first lower end processing mode. Consequently, the correction values of the first through 36th records of the correction value table for the first lower end processing mode are successively correlated to the first through 36th pixel data rows while the pixel data making up each pixel data row are corrected. The intermediate-only region, which is printed through the first intermediate processing mode only, is specified as the region from r41 to r85 of the print region r1 to r121 based on the region determination table. The data of the raster lines of the region r41 to r85 are the pixel data rows of the 41st to 85th rows in the K image data. On the other hand, the correction values corresponding to the intermediate-only region are recorded in the first through 45th records of the correction value table for the first intermediate processing node. Consequently, the correction values of the first through 45th records of the correction value table for the first intermediate processing mode are successively correlated to the 41st through 85th pixel data rows while the pixel data making up each pixel data row are corrected. It should be noted that, as mentioned above, the number of passes of the first intermediate processing mode is not fixed like in the first upper end processing mode etc., and rather changes depending on the paper size mode that has been input. Thus, the number of pixel data rows in the intermediate-only region changes depending on the paper size mode. Here, the correction value table for the first intermediate processing mode includes correction values for only the fixed number of 45 records from the first record through the 45th record, giving rise to a possibility that the number of correction values will run out in the latter half when correlating them to a pixel data row. This is dealt with by utilizing the periodicity of the combination of nozzles forming adjacent raster lines. In other words, as shown in the right diagrams of FIG. 21A and FIG. 21B, the order of the nozzles forming the raster lines in the intermediate-only region r41 to r85, which is printed by only the first intermediate processing mode, in a single cycle is #2, #4, #6, #1, #3, #5, and #7, and this cycle is repeated. This cycle is increased by one cycle each time the pass number of the first intermediate processing mode increases by one. Consequently, it is possible to use the correction values of this one cycle for the row numbers for which there is not a corresponding correction value That is, the correction values from the first record to the seventh records, for example, corresponding to this cycle can be used repeatedly for the rows for which the correction values have run out. Step S145: Next, the printer driver 1110 executes rasterization. The rasterized print data are output to the printer 1, and the printer 1 executes actual printing of the image to the paper S according to the pixel data of the print data. It should be noted that as discussed above, the darkness of the pixel data has been corrected for each raster line, and thus darkness nonuniformities can be effectively inhibited in the image that is printed. (2) Regarding the Method for Correcting the Pixel Data Based on the Correction Values Next, the method for correcting the pixel data based on the correction values is described in detail. As mentioned above, pixel data having gradation values of 256 grades are converted into pixel data having gradation values of four grades indicating “no dot formation,” “small dot formation,” “medium dot formation,” and “large dot formation” through halftone processing. During this conversion, the 256 gradations are first substituted with level data and then converted into four gradations. Accordingly, in the present embodiment, at the time of this conversion the level data are changed by the amount of the correction value so as to correct the pixel data of gradation values having four grades, thus performing “correction of pixel data based on the correction value.” It should be noted that the halftone processing here differs from the halftone processing that has already been described using FIG. 3 in that it includes steps S301, S303, and S305 for setting the level data, and otherwise the two are identical. Consequently, the following description focuses on this difference, and aspects that are the same have been summarized. Further, the following description is made using the flowchart of FIG. 3 and the dot creation ratio table of FIG. 4. First, the printer driver 1110 obtains the K image data in step S300 like in ordinary halftone processing. It should be noted that at this time the C, M, and Y image data also are obtained, but because the following description can be applied to any of the C, M, and Y image data as well, the description is made with the K image data representing these image data. Next, in step S301, the printer driver 1110 reads, for each pixel data, the level data LVL corresponding to the gradation value of that pixel data from the large dot profile LD of the creation ratio table. However, in the present embodiment, when the level data LVL are read, the gradation value is shifted by the correction value H corresponding to the pixel data row to which the pixel data belong. For example, if the gradation value of the pixel data is gr and the pixel data row to which that pixel data belongs is the first row, then that pixel data row is correlated to the correction value H of the first record in the recording table for the first upper end processing. Consequently, the level data LVL is read shifting the gradation value gr by a value Δgr (=gr×H) that is obtained by multiplying the correction value H by the gradation value gr, obtaining a level data LVL of 11d. In step S302, the printer driver 1110 determines whether or not the level data LVL of this large dot is greater than the threshold value THL of the pixel block corresponding to that pixel data on the dither matrix. Note that the level data LVL has been changed by the value Δgr based on the correction value H. Consequently, the result of this determination changes by the amount of change, and thus the tendency of a large dot being formed also changes. As a result, the “correction of pixel data based on the correction value” mentioned above is achieved. It should be noted that if in step S302 the level data LVL is larger than the threshold value THL, then the procedure is advanced to step S310 and a large dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S303. In step S303, the printer driver 1110 reads the level data LVM corresponding to the gradation value from the medium dot profile MD of the creation ratio table, and at this time, as in step S301, the level data LVM is read shifting the gradation value by the amount of the correction value (for example, by the value Δgr (=gr×H)). Doing this, a level data LVM of 12d is obtained. Next, in step S304 the printer driver 1110 determines whether or not the level data LVM of this medium dot is greater than the threshold value THM of the pixel block corresponding to that pixel data on the dither matrix. Here also, the level data LVM has been changed by the value Δgr based on the correction value H. Consequently, the result of this size determination is changed by that amount of change, and thus the tendency of a medium dot being formed also changes, thus achieving the “correction of pixel data based on the correction value” mentioned above. It should be noted that if in step S304 the level data LVM is larger than the threshold value THM, then the procedure is advanced to step S309 and a medium dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S305. In step S305 the printer driver 1110 reads the level data LVS corresponding to the gradation value from the small dot profile SD of the creation ratio table, and like in step S301, at this time it reads the level data LVS shifting the gradation value by the amount of the correction value (for example, by the value Δgr (=gr×H)). Doing this, a level data LVS of 13d is obtained. Then, in step S306 the printer driver 1110 determines whether or not the level data LVS of this small dot is larger than the threshold value THS of the pixel block corresponding to that pixel data on the dither matrix. Here as well, the level data LVS has been changed by the value Δgr based on the correction value H. Consequently, the result of this size determination changes by this amount of change, and thus the tendency of a small dot being formed also changes, thus achieving the “correction of pixel data based on the correction value” mentioned above. It should be noted that if in step S306 the level data LVS is larger than the threshold value THS, then the procedure is advanced to step S308, and a small dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S307 and no dot is recorded corresponding to that pixel data. <Regarding the Combination With the Other Correction Value for Correcting the Darkness in the Carriage Movement Direction> Next, an embodiment in which darkness correction is performed combining an other correction value H2 for correcting the darkness in the carriage movement direction and the above-described correction values H for each raster line. As mentioned above, darkness nonuniformities in the carriage movement direction (see FIG. 25B) occur due to mechanical causes such as vibration of the carriage 31. Such darkness nonuniformities in the carriage movement direction that are repeatable can be corrected by adopting the above correction method. In other words, darkness nonuniformities in the carriage movement direction also can be corrected by obtaining, from the darkness of a plurality of pixels lined up at the same position in the carriage direction, an other correction value H2 for that position and setting the other correction values H2 in correspondence with the pixels lined up in the carriage movement direction. With this method, the printer driver 1110, when obtaining print data, corrects the darkness of a target pixel using both the correction value H and the other correction value H2. Then, the printer 1 forms the dots of the corresponding lines in the dot forming operations such that their darkness becomes the darkness corrected based on the correction value H and the other correction value H2. As a result, darkness nonuniformities in the carriage movement direction also can be inhibited, allowing darkness nonuniformities in the image to be effectively inhibited. <Regarding the Other Correction Values> FIG. 45 is a diagram that for schematically illustrating the pixels PX formed on the paper S, and the other correction values H2 will be described with reference to this diagram. In this diagram, the left-right direction is the carriage movement direction and the up-down direction is the carrying direction of the paper S. Further, this diagram shows a magnification of a portion of the paper S, and each grid square in lattice on the paper S indicates a single pixel PX. The other correction values H2 mentioned above are set for each pixel PX lined up in the carriage movement direction (main-scanning direction). Using the virtual lines VL shown by the dashed lines (straight lines in the carrying direction, set for each pixel) in the drawing to describe the other correction values H2, the other correction values H2 are set in units of pixels lined up in the main-scanning direction, and each correction value can be regarded as a correction value that can be used in common for a plurality of pixels PX on the same virtual line VL. The method for printing an image using the other correction values H2 is the same as the method for printing an image using the correction values H. That is, as described in the flowchart of FIG. 29, first the printer 1 is assembled on the manufacturing line (S110), then the correction values H and the other correction values H2 are set to the printer 1 (S120). Next, the printer 1 is shipped (S130), and then the user during actual printing prints an image on the paper S while performing darkness correction (S140). Here, the difference between this embodiment and the embodiment discussed above is primarily in the process for setting the correction values (step S120) and the actual printing of the image (step S140). In other words, in the processing for setting the correction values of this embodiment, a correction value H is set for each raster line and an other correction value H2 is set for each dot in the main-scanning direction. Further, during actual printing of the image, the dot creation ratio is changed using both the correction value H and the other correction value H2. Consequently, the step S120 and the step S140 are described below. <Step S120: Setting the Darkness Correction Values to Inhibit Darkness Nonuniformities> In this embodiment, the equipments that are used for setting the correction values H and the other correction values H2 is the same as the equipments described in FIG. 30. Thus, only the differences are described below, and common sections are assigned common reference numerals and description thereof is omitted. FIG. 46 is a conceptual diagram of a recording table for obtaining the other correction values H2 (for convenience, it is referred to as “other recording table”). It should be noted that also in this embodiment, the computer 1100A is provided with the recording table shown in FIG. 31 (the recording table described above for recording measurement values and command values). Again, the other recording tables also are provided in the memory of the computer 1100A. The other recording tables are prepared for each ink color. Here, the reason why a recording table is not provided for each processing mode is because darkness nonuniformities in the carriage movement direction occur for reasons unrelated to the processing mode, such as due to vibration of the carriage 31. Further, the measurement values of the correction patterns CP printed in each division are recorded in the corresponding recording table. It should be noted that this diagram shows the recording table for black (K) as a representative recording table. The measurement values Ca, Cb, and Cc for the three correction patterns CPka, CPkb, and CPkc, which each have different darkness, and command values Sa, Sb, and Sc corresponding to those measurement values are recorded in the other recording tables. Thus, six fields are prepared in each recording table. In the records of the first field and the fourth field from the left of the table are recorded the measurement value Ca, and its command value Sa, for the correction pattern CPka, which has the lightest darkness. Further, in the records of the third field and the sixth field from the left are recorded the measurement value Cb, and its command value Sb, for the correction pattern CPkb, which has the darkest darkness. Likewise, in the records of the second field and the fifth field from the left are recorded the measurement value Cc, and its command value Sc, for the correction pattern CPkc, which has an intermediate darkness. A record number is assigned to each record, and in the small number records, the measurement values of the small number main-scanning positions in the corresponding correction patterns CP are successively recorded. It should be noted that the numbers of the main-scanning positions can be assigned from the left side or the right side of the paper S, but for convenience sake, in this embodiment the left edge of the paper S is given the smallest number and the right edge of the paper S is given the largest number. The number of records that are provided is the number that can correspond to the overall width of the print region A (length in the carrying direction). For the three correction patterns CPka, CPkb, and CPkc, the measurement values Ca, Cb, and Cc and the command values Sa, Sb, and Sc of the same main-scanning position are all recorded in a record with the same record number. FIG. 47 is a conceptual diagram of the correction value storage section 63a provided in the memory 63 of the printer 1, and shows a correction value table for storing the other correction values H2 (for convenience, it is referred to as the “other correction value table”). It should be noted that, although omitted from the figure, the printer 1 is also provided with the correction value tables shown in FIG. 32 in addition to the other correction value tables. As shown in the drawing, the other correction value tables, like the other recording tables mentioned above, are provided for each ink color. This diagram shows the other correction value table for black (K) as a representative table. The other correction value tables, as well, have records for recording a correction value. Each record is assigned a record number, and a correction value calculated based on the measurement values is recorded in the record having the same record number as the record for those measurement values. Consequently, the number of records that are provided is the number that can correspond to the overall width of the print region A. FIG. 48 is a flowchart showing the specifics of the procedure of step S120 in FIG. 29 (that is, the procedure for setting the correction value H and the other correction value H2). As shown in this flowchart, the setting procedure illustrated here includes a step of printing a correction pattern CP (S121), a step of reading the correction pattern CP (S122), a step of obtaining the pixel darkness of the each raster line (S123), a step of setting a darkness correction value for each raster line (S124), a step of printing an other correction pattern CP (S125), a step of reading the other correction pattern CP (S126), a step of measuring the pixel darkness at each main-scanning position (S127), and a step of setting a darkness correction value for each main-scanning position (S128). These steps are described in detail below. Here, the procedure (1) of printing the correction pattern CP (S121) through the procedure (4) of setting the darkness correction value (S124) are the same as those in the embodiment discussed above. Thus, description of these processes is omitted, and the following description starts from the procedure (5) of printing the other correction pattern CP (S125). (5) Regarding Printing the Other Correction Pattern CP (S125) In step S125 an other correction pattern CP is printed on the paper S. Here, a worker on the inspection line gives out a command to print the other correction pattern CP through a user interface of the computer 1100. At that time, the print mode and the paper size mode are set through the user interface. Due to this command, the computer 1100 reads the image data of the other correction pattern CP stored on the memory and performs the above-mentioned processes of resolution conversion, color conversion, halftone processing, and rasterization. Then, when performing halftone processing, the correction values H set in step S124 are used to correct the darkness of the raster lines. When rasterization is performed, the computer 1100 outputs print data for printing the other correction pattern CP to the printer 1. The printer 1 prints the other correction pattern CP on the paper S based on the print data. At the time of this printing, a raster line is formed in the dot formation process such that the darkness becomes the darkness corrected based on the correction value H. It is clear from the above that in this embodiment, when printing the other correction pattern CP, the above-described correction value H is used and the corresponding raster line is formed at the darkness corrected by that correction value H. By adopting this method, the other correction pattern CP is printed at a darkness that has been corrected by the correction value, and thus darkness nonuniformities in the carrying direction have been corrected. The pixel darkness of the other correction pattern CP is measured, after correction, to obtain an other correction value H2, and thus it is possible to suppress fluctuation in the measured pixel darkness and thereby increase the reliability of the other correction value H2. FIG. 49 is a diagram for describing an example of the other correction pattern CP. As shown in the drawing, the other correction pattern CP of the present embodiment is printed in divisions of ink color and darkness. That is, the other correction pattern CP can be said to have a plurality of types of band-shaped patterns each having a different ink color and darkness. The gradation values of the pixel data in the other correction pattern CP are set to the same value for each division of darkness. Thus, each correction pattern CP is printed at substantially the same darkness over the entire region in the carriage movement direction. In the other correction pattern CP that is shown, the first through third patterns from the upper end of the paper are the other correction patterns CP for cyan (C). The fourth through sixth patterns from the upper end of the paper are the other correction patterns CP for magenta (M). The seventh through ninth patterns from the upper end of the paper are the other correction patterns CP for yellow (Y), and the tenth through twelfth patterns from the upper end of the paper are the other correction patterns CP for black (K). The patterns for each color have different print darkness. In other words, the patterns for each color are a pattern that is printed at a reference gradation value at which darkness nonuniformities occur easily, a pattern that is printed at a low-darkness-side gradation value that is lower than the reference gradation value, and a pattern that is printed at a high-darkness-side gradation value that is higher than the reference gradation value. Using black as an example, the upper pattern CPka (the tenth pattern from the upper end of the paper) is printed at the low-darkness-side gradation value, the middle pattern CPkc (the eleventh pattern from the upper end of the paper) is printed at the reference gradation value, and the lower end pattern CPkb (the twelfth pattern from the upper end of the paper) is printed at the high-darkness-side gradation value. It should be noted that the reference gradation value, the low-darkness-side gradation value, the high-darkness-side gradation value, and the reason why a pattern with a plurality of darkness is used, are the same as those with regards to the correction pattern CP mentioned above, and thus description thereof is omitted. In principle, the only difference between the other correction patterns CP is the ink color. For this reason, hereinafter the black (K) correction pattern CPk is described as a representative correction pattern CP. Further, in the following description there are sections that describe only the color black (K), but as mentioned above, the same also applies for the other ink colors C, M, and Y as well. The other correction pattern CPk that is illustratively shown is printed in a band shape that is long in the carriage movement direction. The print region in the carrying direction is approximately the entire region from one side of the paper S in the width direction (the direction corresponding to the carriage movement direction) to the other. In this embodiment, printing of the other correction pattern CP is stopped slightly before the edge of the paper S, forming a margin. In these margins, a vertical reference ruled line RL1 extending in the carrying direction (these correspond to the “intersecting-side reference ruled line” in the claims) is formed. The vertical reference ruled lines RL1 are the same as those in the above embodiment, and are used when correcting tilt in the image data read by the scanner device 100. Further, horizontal reference ruled lines RL2 (these correspond to the “movement-side reference ruled line” in the claims) is formed in the carriage movement direction both above the upper cyan pattern toward the upper end of the paper S and below the lower black pattern toward the lower-end side of the paper S. The horizontal reference ruled lines RL2 also are used when correcting tilt in the image data read by the scanner device 100. Further, in the present embodiment, index markers IM indicating the position of the paper S are printed in the margin on the left or right side of the paper S, and more specifically in the corner portions of the paper S. The index markers IM are used when recognizing the right and the left of an image in image data obtained by reading with the scanner device 100. In other words, when reading the darkness of the correction pattern CP, the computer 1100 determines the left and right side of the image that has been read based on the index markers IM. Thus, when reading the correction pattern CP, even if a worker on the inspection line mistakes the left and right sides of the correction pattern CP when placing the paper S on the original document bed, measurement can be performed without problem. It should be noted that the other correction pattern CP of FIG. 49 is only one example, and it can be suitably changed. For example, if the other correction value H2 is required over the entire carriage movement direction (main-scanning direction), then the other correction patterns CP of the respective colors can be formed contiguously over the entire region in the width direction of the paper S. In this case, only the horizontal reference ruled lines RL2 are printed, and the vertical reference ruled lines RL1 are not printed. That is, it is only necessary that at least one of either the vertical reference ruled lines RL1 and the horizontal reference ruled lines RL2 are formed. (6) Reading the Other Correction Patterns CP (Step S126) Next, the other correction patterns CP that have been printed are read by the scanner device 100. In step S126, first a worker on the inspection line places the paper S on which the other correction patterns CP have been printed onto the original document bed 102. Once the paper S has been placed, the worker specifies the reading conditions through the user interface of the computer 1100 and then gives out a command to initiate reading. Here, it is preferable that the reading resolution in the movement direction of the reading carriage 104 is several integer multiples finer than the pitch between dots adjacent in the main-scanning direction. By doing this, the measurement values of the darkness that is read and the pixels can be correlated easily, allowing the measurement accuracy to be increased. When it has received the command to initiate reading, the controller (not shown) of the scanner device 100 controls the reading carriage 104, for example, to read the other correction patterns CP printed on the paper S and obtain data groups in units of pixels. The data groups that are obtained are then transferred to the memory of the computer 1100. In this case as well, the pitch at which adjacent light-receiving elements are arranged in the linear sensor 108 and the pitch at which the dots are formed in the other correction patterns CP do not always match. Thus, as mentioned above, the point where the dots and the path over which the light-receiving elements move intersect one another is not fixed, and fluctuations occur in the detection darkness. Consequently, the darkness of the pixels after being read by the scanner device 100 becomes irregular for example due to the position where the dots are read, as shown in FIG. 50. Further, the other correction patterns CP are printed in halftone, and thus discrepancies may also occur due to the size of the dots. Accordingly, the darkness of a plurality of pixels at the same main-scanning position is measured, and the other correction value H2 is obtained based on the darkness. (7) Measuring the Darkness of the Other Correction Patterns CP (Step S127) FIG. 51 is a flowchart showing in detail the procedure of the step S127 in FIG. 48. The computer 1100A executes the procedure of the step S127 under the process correction program. Measurement of the darkness of the other correction patterns CP is described below with reference to this flowchart. The computer 1100A first in step S127a performs tilt correction of the transferred data groups (S127a). This tilt processing is the same as the tilt processing described above (S123a; see FIG. 39 and FIG. 40). That is, in step S127a the computer 1100 obtains the coordinates of the vertical reference ruled lines RL1 and the horizontal reference ruled lines RL2, and calculates the amount of deviation from a reference position for each raster line or each virtual line. The computer 1100 then shifts the data of the corresponding pixels based on the amount of deviation that has been calculated. Once this correction has been performed for every raster line and every virtual line in the image of the other correction patterns CP, the procedure is advanced to step S127b. By performing tilt correction, even if the correction pattern CP has been read shifted off of the normal position, this shifting can be corrected. Then, because the pixel darkness is measured after shifting has been corrected, the reliability of the correction values H and the other correction values H2 can be increased. Further, shifting of the pattern can be automatically corrected through the above image processing. Therefore, an increase in processing efficiency can also be achieved. Next, the computer 1100 measures the darkness of a plurality of pixels at the same main-scanning position of the correction pattern CP. First, the computer 1100 obtains position information for a first main-scanning position to be measured (S127b). In this embodiment, darkness is measured from the main-scanning position on the furthermost left, and thus a value “1” (X=1) is obtained as the data for the main-scanning position. Once the information on the main-scanning position has been obtained, the computer 1100 obtains position information indicating the position in the sub-scanning direction of the pixel to be measured (S127c). Here, the position in the sub-scanning direction differs depending on the other correction pattern CP to be measured. Thus, in this step, Y1 (Y=Y1) is obtained as the sub-scanning position information. It should be noted that as shown in FIG. 49, the other correction patterns CP of this embodiment have a narrow band-shape that is long in the horizontal direction, and as will be discussed later, the pixel to be measured moves successively toward the lower end of the paper S. Thus, it is preferable that the position in the sub-scanning direction is set to a position on the upper end of the correction patterns CP. Once the information X on the main-scanning position and the information Y on the sub-scanning position have been obtained, the darkness of the pixel specified by these positions is obtained (S127d). Once the darkness of this pixel has been obtained, the value of the Y coordinate is increased by 1 (Y=Y+1) (S127e). That is, the pixel to be measured is reset to the pixel adjacent toward the lower end in the carrying direction. Then, it is determined whether or not the new Y coordinate that is obtained by adding 1 is greater than a threshold value (Y1+n) (S127f). Here, if the Y coordinate does not exceed the threshold value (Y1+n), then the procedure is returned to step S127d and the darkness of the pixel specified by the new Y coordinate is obtained. It should be noted that the threshold value is defined as the number of pixels whose darkness is to be obtained (corresponds to n above). This number of pixels can be set to any value, but like in the above embodiment, preferably it is set to within a range from several tens to several hundreds of pixels, and more preferably is set to within the range of 50 to 200. In the present embodiment, it has been set to 50. Thereafter, the operations of the steps S127d to S127f are repeated, successively obtaining the darkness of the pixels. If it is determined in step S127f that the Y coordinate has exceeded the threshold value (Y1+n), that is, if the darkness for the last pixel to be measured at that main-scanning position has been measured, then the procedure advances to step S127g, and the average darkness value of the n-number of pixels to be measured is found. Once the average darkness value has been obtained, the procedure advances to step S127h, and the average darkness value that has been obtained is stored in the corresponding record of the recording table as the darkness at that main-scanning position. Once the average darkness value has been stored, the above procedure is performed for the next main-scanning position. That is, in step S127i the value of the X coordinate is increased by 1 (X=X+1). In other words, the main-scanning position to be measured is reset to a pixel that is positioned adjacent to the right in the main-scanning direction. It is then determined whether or not the new X coordinate that has been obtained by adding 1 is greater than the final main-scanning position (S127j). Here, if the X coordinate has not exceeded the final main-scanning position, then the procedure is returned to step S127c and the darkness of the main-scanning position specified by the new X coordinate is obtained (S127c to S127h). On the other hand, if the X coordinate does exceed the final main-scanning position, then darkness measurement for that correction pattern CP is ended, and darkness measurement for the next correction pattern CP is performed. Due to the reasons discussed above, irregularities can occur in the measured darkness between pixels, even for pixels at the same main-scanning position. Therefore, it can be understood that by taking an average of a plurality of pixels at that main-scanning position it is possible to accurately obtain the darkness at each main-scanning position. It should be noted that in this procedure as well, the plurality of pixels whose darkness is measured are adjacent to one another; this is to take into account the possibility that darkness nonuniformities in the carrying direction (sub-scanning direction) may occur periodically. As mentioned above, in this embodiment the darkness nonuniformities that occur in the carrying direction are corrected, but the difference in dot size remains. Thus, by using the average darkness of a plurality of pixels, it is possible to effectively inhibit darkness irregularities between the pixels due to differences in the dot size. (8) Setting the Darkness Correction Value for Each Main-Scanning Position (Step S128) Next, the computer 1100 sets the darkness correction value for each main-scanning position. Here, the computer 1100 calculates the darkness correction value based on the measured values that have been recorded in the records of the recording tables (see FIG. 46), and records this other correction value in the corresponding record of the correction value storage section 63a of the printer 1 (see FIG. 47). Next, this other correction value is found in a correction ratio format that indicates the ratio of correction with respect to the gradation value of the darkness; more specifically, this is performed in accordance with the flowchart of FIG. 52. First, the computer 1100 calculates the other correction value H2 (S128a). Here, the other correction value H2 is calculated by performing primary interpolation using the three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc) of the pairing between the command values Sa, Sb, and Sc and the measurement values Ca, Cb, and Cc recorded to the records of the recording tables, and that other correction value H2 is set in the other correction value table. It should be noted that the details of this setting procedure are the same as those for setting a darkness correction value for each raster line described above. That is, the other correction value H2 is obtained by substituting concrete values for Ca, Cb, Cc, Sa, Sb, Sc, Ss, and Ss1 in following Formulas 3, 5, and 7′. So=(Ss1−Ca)/[(Ca−Cc)/(Sa−Sc)]+Sa Formula 3 So=(Ss1−Cc)/[(Cc−Cb)/(Sc−Sb)]+Sc Formula 5 H2=ΔS/Ss=(So−Ss)/Ss Formula 7′ In this processing the other correction value is obtained through primary interpolation, and thus the processing is simplified, allowing work efficiency to be improved. Further, because three information pairs are used in this process, the other correction value H2 can be calculated with high accuracy. In other words, in general, the slope between lines used for primary interpolation may be different in the range of a higher darkness and the range of a lower darkness than the reference. In such cases as well, with this method, primary interpolation can be performed using the two information pairs of (Sb, Cb) and (Sc, Cc) with respect to the range of higher darkness than the reference darkness, and primary interpolation can be performed using the two information pairs of (Sa, Ca) and (Sc, Cc) with respect to the range of lower darkness than the reference darkness. Thus, the other correction value H2 can be calculated with high accuracy even when the slope between lines used for primary interpolation is different. Then, the other correction value H2 that is obtained in this manner is stored in the other correction value table shown in FIG. 47 (S128b). In other words, the computer 1100 reads the three information pairs (Sa, Ca), (Sb, Cb), and (Sc, Cc) from the same record on the recording table and substitutes these into Formula 3, Formula 5, and Formula 7 to calculate the other correction value H2, and then records the calculated other correction value to the record of the same record number in the other correction value table. Thus, by using this other correction value H2 to perform darkness correction, which is discussed later, fluctuations in the darkness in each main-scanning position can be made small for each ink color, allowing darkness nonuniformities to be inhibited even more. <Step S140: Actual Printing of the Image While Performing Darkness Correction for Each Raster Line> The printer 1 in which darkness correction values have been set in this manner is shipped and used for an actual printing by a user. In the actual printing, the printer driver 1110 and the printer 1 work in cooperation to perform darkness correction for each raster line and execute printing in which darkness nonuniformities are inhibited. The operation here is the same as the operation in the above embodiment. That is, the printer driver 1110 changes the 2-bit pixel data based on the correction value when converting the RGB image data into print data. It then outputs print data based on the corrected image data to the printer 1. The printer 1 forms the dots of the corresponding raster line based on those print data. (1) Regarding the Method for Correcting Pixel Data Based on the Correction Value: Correction of the pixel data based on the correction value is performed through halftone processing, as in the embodiment discussed above. In halftone processing, pixel data having gradation values of 256 grades are converted into pixel data having gradation values of four grades indicating “no dot formation,” “small dot formation,” “medium dot formation,” and “large dot formation”. During this conversion, the 256 gradations are first substituted with level data and then converted into gradation values of four gradation. In the present embodiment, at the time of this conversion, the level data are changed by the amount of the correction value H and the other correction value H2 so as to correct the four-gradation-value pixel data, thus performing “correction of pixel data based on the correction value and the other correction value.” It should be noted that the halftone processing here differs from the halftone processing that has already been described using FIG. 3 in that it includes steps S301, S303, and S305 for setting the level data, and otherwise the two are identical. Consequently, this difference is emphasized in the following description, and aspects that are the same have been summarized. Further, the following description is made with reference to the flowchart of FIG. 3 and the dot creation ratio table of FIG. 4. First, the printer driver 1110 obtains the K image data in step S300 like in ordinary halftone processing. It should be noted that at this time the C, M, and Y image data also are obtained, but because the following description can be applied to any of the C, M, and Y image data as well, the K image data are described representing these image data. Next, in step S301, the printer driver 1110 reads, for each pixel data, the level data LVL corresponding to that pixel data gradation value from the large dot profile LD of the creation ratio table. However, in the present embodiment, when the level data LVL are read, their gradation value is shifted by the correction value H corresponding to the raster line (pixel data row) to which the pixel data belongs and by the correction value H2 corresponding to the main-scanning position to which the pixel data belongs. For example, if the gradation value of the pixel data is gr and the pixel data row to which that pixel data belongs is the first row, then that pixel data row is correlated to the correction value H of the first record in the recording table for the first upper end processing. Consequently, the gradation value gr is shifted by a value Δgr (=gr×H) that is obtained by multiplying the correction value H by the gradation value gr. Further, if that pixel data belongs to the first main-scanning position (pixel on the left edge), then that pixel data row is correlated to the correction value H2 of the first record in the recording table. Consequently, the gradation value gr is further shifted by a value Δgr2 (=gr×H2) that is obtained by multiplying this other correction value H2 by the gradation value gr. It should be noted that in the example of the diagram, the value Δgr2 is a correction value correcting toward the lower-darkness side. Thus, the level data LVL of the gradation value indicated by (gr+Δgr)−Δgr2 is read in step S301. As a result, the level data LVL is found to be 21d. In step S302, the printer driver 1110 determines whether or not the level data LVL of this large dot is greater than the threshold value THL of the pixel block corresponding to that pixel data on the dither matrix. Further, the level data LVL is changed by the value Δgr and the value Δgr2 based on the correction value H and the correction value H2. Consequently, the result of this size determination is changed by that amount of change, and thus the tendency of the large dots being formed also changes. As a result, the “correction of pixel data based on the correction value and the other correction value” mentioned above is achieved. If in step S302 the level data LVL is larger than the threshold value THL, then the procedure is advanced to step S310 and large dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S303. In step S303, the printer driver 1110 reads the level data LVM corresponding to the gradation value from the medium dot profile MD of the creation ratio table, and at this time, as in step S301, the level data LVM is read shifting the gradation value by the value Δgr and the value Δgr2. As a result, a level data LVM of 22d is obtained. Next, in step S304, the printer driver 1110 determines whether or not the level data LVM of this medium dot is greater than the threshold value THM of the pixel block corresponding to that pixel data on the dither matrix. Here also, the level data LVM is changed by the values Δgr and Δgr2. Consequently, the result of this size determination is changed by that amount of change, and thus the tendency of the medium dots being formed also changes, and as a result, the “correction of pixel data based on the correction value and the other correction value” mentioned above is achieved. If in step S304 the level data LVM is larger than the threshold value THM, then the procedure is advanced to step S309 and a medium dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S305. In step S305, the printer driver 1110 reads the level data LVS corresponding to the gradation value from the small dot profile SD of the creation ratio table, and like in step S301, at this time the level data LVS is read shifting the gradation value by the values Δgr and Δgr2. As a result, a level data LVS of 33d is obtained. Then, in step S306, the printer driver 1110 determines whether or not the level data LVS of this small dot is larger than the threshold value THS of the pixel block corresponding to that pixel data on the dither matrix. Here as well, the level data LVS is changed by the value Δgr based on the correction value H and Δgr2 based on the other correction value H2. Consequently, the result of this size determination changes by that amount of change, and thus the tendency of the small dots being formed also changes, and as a result, the “correction of pixel data based on the correction value and the other correction value” mentioned above is achieved. It should be noted that if in step S306 the level data LVS is larger than the threshold value THS, then the procedure is advanced to step S308, and a small dot is recorded corresponding to that pixel data. Otherwise the procedure is advanced to step S307 and no dot is recorded corresponding to that pixel data. Other Embodiments The above embodiment was written primarily with regard to the printer 1, but the above embodiment of course also includes the disclosure of a printing device, a printing method, and a printing system, for example. A printer 1, for example, was described as one embodiment, but the foregoing embodiment is for the purpose of elucidating the present invention and is not to be interpreted as limiting the present invention. The invention can of course be altered and improved without departing from the gist thereof and includes equivalents. In particular, the embodiments discussed below are also included in the present invention. <Regarding the Printer> In the above embodiments, the printer 1 and the scanner device 100 are configured separately, and each is communicably connected to the computer 1000A. However, application of the present invention is not limited this configuration. For example, the present invention can also be applied to a so-called printer-scanner multifunction device that has both the function of the printer 1 and the function of the scanner device 100. Further, a printer 1 was described in the above embodiments, but the present invention is not limited to this. For example, the same technology as in the present embodiment can be applied to a various types of devices employing inkjet technology, such as a color filter manufacturing device, a dyeing device, a fine processing device, a semiconductor manufacturing device, a surface processing device, a three-dimensional shape forming machine, a liquid vaporizing device, an organic EL manufacturing device (particularly a macromolecular EL manufacturing device), a display manufacturing device, a film formation device, and a DNA chip manufacturing device, for example. The methods for, and the manufacturing methods of, these also fall within the scope to which the present invention can be applied. <Regarding the Ink> The above embodiment was of the printer 1, and thus a dye ink or a pigment ink was ejected from the nozzles. However, the ink that is ejected from the nozzles is not limited to such inks. <Regarding the Nozzles> In the foregoing embodiments, ink was ejected using piezoelectric elements. However, the method for ejecting ink is not limited to this. For example, it is also possible to employ other methods as well, such as a method where bubbles are generated within the nozzles due to heat. <Regarding the Print Mode> Interlacing was described as an example of the print mode in the above embodiments, but the print mode is not limited to this, and it is also possible to use the so-called overlapping mode. With interlacing, a single raster line is formed by a single nozzle, whereas with overlapping, a single raster line is formed by two or more nozzles. That is, with overlapping, each time the paper S is carried by a predetermined carry amount F in the carrying direction, the nozzles, which move in the carriage movement direction, intermittently eject ink droplets at intervals of every several pixels, intermittently forming dots in the carriage movement direction. Then, in another pass, dots are formed such that the intermittent dots already formed by the other nozzle are completed in a complementary manner. Thus, a single raster line is completed by a plurality of nozzles. <Regarding the Target of Darkness Correction> In the above embodiments, darkness correction is performed based on the correction value H and the other correction value H2 during halftone processing, but the present invention is not limited to this method. For example, it is also possible to adopt a configuration in which darkness correction is performed based on the correction value H and the other correction value H2 with respect to the RGB image data that are obtained through, for example, the resolution conversion processing. <Regarding the Carriage Movement Direction in which Ink is Ejected> The foregoing embodiment describes an example of single-direction printing in which ink is ejected only when the carriage 31 is moving forward, but this is not a limitation, and it is also possible to perform so-called bi-directional printing in which ink is ejected both when the carriage 31 is moving forward and backward. <Regarding the Color Inks Used for Printing> The foregoing embodiment describes an example of multicolor printing in which the four color inks, cyan (C), magenta (M), yellow (Y), and black (K), are ejected onto the paper S to form dots, but the ink colors are not limited to these. For example, it is also possible to use other inks in addition to these, such as light cyan (LC) and light magenta (LM). Alternatively, it is also possible to perform single-color printing using only one of these four colors. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to printing methods, printing apparatuses, and printing systems. 2. Description of the Related Art Inkjet printers (hereinafter referred to simply as “printers”) that eject ink onto a medium such as paper to form dots are known as printing apparatuses for printing images. These printers repeat in alternation a dot forming operation of forming dots on a paper by ejecting ink from a plurality of nozzles, which move in the movement direction of a carriage, and a carrying operation of carrying, using a carrying unit, the paper in an intersecting direction (hereinafter, also referred to as the “carrying direction”) that intersects the movement direction. By doing this, a plurality of raster lines made of a plurality of dots in the movement direction are formed in the intersecting direction, thereby printing an image. With this type of printer, there are discrepancies in the ink droplet ejection characteristics, such as the quantity of the ink droplet and the travel direction, among the nozzles. Discrepancies in the ejection characteristics are a cause of darkness nonuniformities in printed images, and thus are not preferable. Accordingly, a conventional method involves setting a correction value for each nozzle and adjusting the quantity of ink based on those correction values that are set. (See, for example, JP H06-166247A (pg. 4, 7, and 8).) With this conventional method, first, correction patterns are printed on the paper. Printing of these correction patterns is performed by moving a head, which is provided with the nozzles, in a scanning direction while intermittently ejecting ink from all of the nozzles. Then, the darkness of the correction patterns that are printed is measured for each pixel. This darkness measurement is performed in the carrying direction for one spot in the scanning direction of the correction patterns. However, with this conventional method, there is a possibility that the darkness that is obtained will change depending on the measurement position, even when measuring the same pixel. This is due to the fact that the dots that are formed are circular. In other words, with this type of printer, the dots that land on the paper spread out in a circular manner. The darkness thus differs between a case where the darkness is measured along a straight line that passes over the center of the dot and a case where the darkness is measured along a straight line that passes over the edge of the dot. That is, the darkness of the latter will be lower than the darkness of the former. Therefore, it is difficult to obtain an accurate darkness by measuring only one spot in the main-scanning direction. Further, with this method there is also a possibility that the quality of the printed image will drop if interlacing is adopted as the print mode. Interlacing is a print mode in which a raster line that is not formed is set between raster lines that are formed in a single dot forming operation, and through a plurality of dot forming operations all of the raster lines are formed in a complementary manner, and with this print mode, adjacent raster lines are not printed by the same nozzle. Also, with interlacing, the nozzle that forms an adjacent raster line will not always be the adjacent nozzle. That is to say, it is possible for the combination of nozzles that form adjacent raster lines in the printed image to be different from the combination in the correction patterns. Here, darkness nonuniformities caused by bending in the flight path of the ink occur due to the spacing between adjacent raster lines becoming small or large, and also occur due to the combination of the nozzles forming the adjacent raster lines. Therefore, it is difficult to correct darkness nonuniformities that result from the combination of raster lines and nozzles using a correction pattern that is printed by ejecting ink from all of the nozzles. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention was arrived at in light of the foregoing issues, and it is an object thereof to achieve a printing method, a printing apparatus, and a printing system with which darkness nonuniformities can be effectively inhibited. An aspect of the present invention is a printing method comprising the steps of: printing, on a medium, a correction pattern that is made of a plurality of lines, the plurality of lines being formed by repeating in alternation a dot forming operation of forming dots on the medium by ejecting ink from a plurality of nozzles that move in a predetermined movement direction, and a carrying operation of carrying the medium in an intersecting direction that intersects the movement direction; measuring, for each line of the correction pattern, the darkness of a plurality of pixels located on a same line of the correction pattern; obtaining, for each line of the correction pattern, a correction value for correcting a darkness, in the intersecting direction, of an image to be printed based on the darkness of the plurality of pixels that has been measured; setting, for each line of the image, the correction value that has been obtained; and forming, in the dot forming operation, dots of a corresponding line for which the correction value has been set such that the darkness of that line becomes a darkness that has been corrected based on that correction value. Other features of the present invention will become clear through the accompanying drawings and the following description. | 20050119 | 20110412 | 20050825 | 65062.0 | 0 | LEBRON, JANNELLE M | PRINTING METHOD, PRINTING APPARATUS, AND PRINTING SYSTEM | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,220 | ACCEPTED | Solid state imaging device and driving method thereof | A solid state imaging device of the present invention comprises a solid state imaging element which includes a plurality of photoelectric conversion elements arranged in a matrix. In the solid state imaging device of the present invention, a pixel mixture unit area includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction. The solid state imaging device includes: means for performing a first-field pixel addition process of adding together electric charges of a plurality of pixels included in the plurality of pixel mixture unit areas and a second-field pixel addition process of adding together the electric charges of the plurality of pixels included in the plurality of pixel mixture unit areas based on a combination of the pixel mixture unit areas which is different from that of the first-field pixel addition process; and means for alternately outputting signals of the electric charges obtained in the first-field pixel addition process and second-field pixel addition process as signals for interlaced scanning. | 1. A solid state imaging device, comprising: a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction; pixel addition means for performing a first-field pixel addition process of adding together electric charges of a plurality of pixels included in the plurality of pixel mixture unit areas and a second-field pixel addition process of adding together the electric charges of the plurality of pixels included in the plurality of pixel mixture unit areas based on a combination of the pixel mixture unit areas which is different from that of the first-field pixel addition process; and output means for alternately outputting signals of the electric charges obtained in the first-field pixel addition process and second-field pixel addition process as signals for interlaced scanning. 2. The solid state imaging device of claim 1, wherein the pixel mixture unit areas overlap one another in the first and second directions to constitute an arrangement which has a two-dimensional repetition. 3. The solid state imaging device of claim 2, wherein: the number of pixels in the first direction in each of the pixel mixture unit areas, q, satisfies the relationship of q=4m+1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, satisfies the relationship of p=4n+1 (n is a natural number); and the pixel mixture unit areas overlap one another by (q+1)/2 pixels in the first direction and by (p+1)/2 pixels in the second direction. 4. The solid state imaging device of claim 2, wherein: the number of pixels in the first direction in each of the pixel mixture unit areas, q, satisfies the relationship of q=4m−1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, satisfies the relationship of p=4n−1 (n is a natural number); and the pixel mixture unit areas repeatedly overlap one another alternately by (q−1)/2 pixels and (q+3)/2 pixels in the first direction and alternately by (p−1)/2 pixels and (p+3)/2 pixels in the second direction. 5. The solid state imaging device of claim 2, wherein: electric charges of a plurality of pixels included in one pixel mixture unit area are added together in the first direction; and the electric charges of the pixels which are added together respectively in the plurality of pixel mixture unit areas and transferred in the first direction are added together in the second direction. 6. The solid state imaging device of claim 2, wherein: the pixel addition means performs a plurality of line processes on two of the pixel mixture unit areas which are adjacent in the first direction wherein electric charges of the plurality of pixels included in the two pixel mixture unit areas are added together; and in at least one of the plurality of line processes, two of the pixel mixture unit areas which are shifted in the second direction by one or more pixels are processed. 7. The solid state imaging device of claim 6, wherein the centroid position of a first region formed by two of the pixel mixture unit areas which are processed in one of the line processes is on a line that extends in the first direction and passes over the median point between the centroid position of a second region formed by two of the pixel mixture unit areas which are processed in another one of the line processes and the centroid position of a third region formed by two of the pixel mixture unit areas which is processed at the same time with the second region and is placed adjacent to the second region in the second direction. 8. The solid state imaging device of claim 1, wherein the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. 9. The solid state imaging device of claim 8, wherein: a color filter arrangement of the solid state imaging element is a combination of Bayer arrangements of 2 rows×2 columns; the pixel addition means includes a first-direction transfer stage for adding together electric charges of the plurality of pixels in the first direction in each of the pixel mixture unit areas and a second-direction transfer stage for adding together the electric charges obtained by the addition in the first-direction transfer stage in the second direction; and the electric charges obtained by the addition in the second-direction transfer stage are pixel signals for complementary color filter arrangement display. 10. The solid state imaging device of claim 8, wherein a color filter arrangement of the solid state imaging element is a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. 11. The solid state imaging device of claim 1, wherein the pixel addition means includes a first-direction transfer stage and a second-direction transfer stage, the first-direction transfer stage including a plurality of CCDs which transfer the electric charges of the pixels in the first direction, the second-direction transfer stage including a plurality of CCDs which transfer the electric charges transferred from the first-direction transfer stage in the second direction. 12. The solid state imaging device of claim 11, wherein: the second-direction transfer stage alternately includes a storage region which includes a first gate and retains an electric charge and a barrier region which includes a second gate and functions as a barrier against transfer of electric charges; and the first gate and the second gate are electrically separated to receive separate biases. 13. A method for driving a solid state imaging device which includes a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction, the method comprising the steps of: (a) adding together electric charges of pixels included in each of the pixel mixture unit areas and transferring the added electric charges in the first direction; (b) adding together electric charges of pixels from a plurality of pixel mixture unit areas while the electric charges added and transferred in the first direction at step (a) are transferred in the second direction; and (c) alternately outputting signals which relates to the electric charges added together at step (b) in first and second fields as signals for interlaced scanning. 14. The method of claim 13, wherein the pixel mixture unit areas overlap one another in the first and second directions to constitute a two-dimensional repetition arrangement. 15. The method of claim 13, wherein: at step (a), electric charges of pixels included in one pixel mixture unit area are added together in the first direction; and at step (b), the electric charges added together in the first direction at step (a) are added together in the second direction. 16. The method of claim 15 wherein, at step (b), a line process of adding together in the second direction electric charges of pixels of two pixel mixture unit areas which are adjacent in the first direction is performed over a plurality of stages. 17. The method of claim 13, wherein the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. 18. The method of claim 17, wherein: a color filter arrangement of the solid state imaging element is a combination of Bayer arrangements of 2 rows×2 columns; and at step (b), electric charges of pixels having different colors in each of the pixel mixture unit areas are added together to generate a pixel signal for a complementary color filter arrangement. 19. The method of claim 17, wherein a color filter arrangement of the solid state imaging element is a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. 20. The method of claim 13, wherein: step (a) uses a first-direction transfer stage including a plurality of CCDs which transfer the electric charges of the pixels in the first direction; and step (b) uses a second-direction transfer stage including a plurality of CCDs which transfer the electric charges transferred from the first-direction transfer stage in the second direction. | CROSS-REFERENCE TO RELATED APPLICATION This application claims priority under 35 U.S.C. §119(a) on Japanese Patent Application No. 2004-13609 filed on Jan. 21, 2004, the entire contents disclosed in the claims, specification and drawings of this application are hereby incorporated by reference. BACKGROUND OF THE INVENTION The present invention relates to a solid state imaging device of a digital still camera, a digital video camera, and the like. Conventionally, a solid state imaging element which converts received light to an electric signal and outputs the electric signal as a video signal has been known, and a camera which displays the video signal obtained from the solid state imaging element in the form of a static image, such as a digital still camera, or the like, has also been known. In recent years, further improvements of image quality and functions have been demanded in such a camera which uses a solid state imaging element, and the number of pixels has been rapidly increasing. For example, a solid state imaging element having about 5,000,000 pixels has about 1,920 pixels in a column (vertical direction) and about 2,560 pixels in a row (horizontal direction). The number of pixels of this element, i.e., about 5,000,000, is about 16 times that of a generally-employed NTSC solid state imaging element. The frame rate for full pixel output is about a ½ second when a conventional pixel clock of about 12 MHz is used. Thus, the video signal output from the solid state imaging element cannot be output to a display device (a liquid crystal monitor, or the like) of the camera without modifying the original frame rate. According to a driving method which has been conventionally employed in view of the above in such a solid state imaging element, the pixels from which signals are to be read are thinned along the horizontal direction while the speed of the pixel clock is increased, whereby a video signal of a moving picture is read with higher speed. For example, signals of pixels on two out of eight lines are used. Further, a technique of reducing the number of output pixels of a solid state imaging element using a pixel mixture method has been known (see Japanese Unexamined Patent Publication No. 2001-36920). However, in the above pixel thinning method, pixels are immoderately resampled in the vertical direction (¼ in the above example), and no associated spatial LPF used for this resampling in the vertical direction is not provided. Accordingly, in an image where a video signal contains high-frequency components in the vertical direction, a large amount of aliasing components deriving from the high-frequency components in the vertical direction occur in the low-frequency range. This causes not only a large number of false signals along with the generation of luminance signals and chromaticity signals but also a significant decrease in the vertical resolution with respect to the horizontal resolution due to an imbalance in pixel sampling density between the horizontal direction and the vertical direction. In addition, since signals of pixels on lines from which no data is to be read out are discarded, the substantial sensitivity decreases. In the above example, the percentage of effectively-used pixels is 25%. In the case where the above-described conventional technique is used, all of the above problems become more serious in principle as the number of pixels of a solid state imaging element increases because it is necessary to decrease the ratio of columns to be read to all of the columns of the solid state imaging element for the purpose of increasing the frame rate. SUMMARY OF THE INVENTION The present invention was conceived to overcome the above problems. An objective of the present invention is to reduce the number of output pixel signals of a solid state imaging element having a large number of pixels, such as a super-megapixel imaging element, or the like, by a pixel addition method, such that moving picture imaging is realized with a super resolution solid image imaging element suitable for a system that operates based on interlaced scanning. In order to achieve the above objective, the present invention includes a solid state imaging element and performs a pixel addition process of the first and second fields wherein the electric charges of a plurality of pixels included in a plurality of pixel mixture unit areas are added together to alternately output signals of the electric charges obtained in the pixel addition process of the first and second fields as signals for interlaced scanning. Specifically, a solid state imaging device of the present invention comprises: a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction; pixel addition means for performing a first-field pixel addition process of adding together electric charges of a plurality of pixels included in the plurality of pixel mixture unit areas and a second-field pixel addition process of adding together the electric charges of the plurality of pixels included in the plurality of pixel mixture unit areas based on a combination of the pixel mixture unit areas which is different from that of the first-field pixel addition process; and output means for alternately outputting signals of the electric charges obtained in the first-field pixel addition process and second-field pixel addition process as signals for interlaced scanning. According to the solid state imaging device of the present invention, a video signal can be read with high speed without thinning pixels to be read. Therefore, signals of all the pixels can be output without abandonment and, accordingly, the sensitivity of the imaging element is greatly improved. Further, aliasing components derived from high frequency components in a low frequency range are greatly reduced. Therefore, false signals are greatly suppressed in both the brightness signal and chromaticity signal. As a result, the image quality improves. In the solid state imaging device of the present invention, preferably, the number of pixels in the first direction in each of the pixel mixture unit areas, q, satisfies the relationship of q=4m+1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, satisfies the relationship of p=4n+1 (n is a natural number); and the pixel mixture unit areas overlap one another by (q+1)/2 pixels in the first direction and by (p+1)/2 pixels in the second direction. Alternatively, the number of pixels in the first direction in each of the pixel mixture unit areas, q, may satisfy the relationship of q=4m−1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, may satisfy the relationship of p=4n−1 (n is a natural number); and the pixel mixture unit areas may repeatedly overlap one another alternately by (q−1)/2 pixels and (q+3)/2 pixels in the first direction and alternately by (p−1)/2 pixels and (p+3)/2 pixels in the second direction. Electric charges of a plurality of pixels included in one pixel mixture unit area may be added together in the first direction; and the electric charges of the pixels which are added together respectively in the plurality of pixel mixture unit areas and transferred in the first direction may be added together in the second direction. With such a structure, the process of adding the electric charges of the pixel in the first direction and the process of adding the electric charges of the pixel in the second direction are clearly separated so that a time-series process can be quickly performed. The pixel addition means may perform a plurality of line processes on two of the pixel mixture unit areas which are adjacent in the first direction wherein electric charges of the plurality of pixels included in the two pixel mixture unit areas are added together; and in at least one of the plurality of line processes, two of the pixel mixture unit areas which are shifted in the second direction by one or more pixels may be processed. With such a structure, the electric charges of pixels of different colors can readily be added together in the second direction. The centroid position of a first region formed by two of the pixel mixture unit areas which are processed in one of the line processes is on a line that extends in the first direction and passes over the median point between the centroid position of a second region formed by two of the pixel mixture unit areas which are processed in another one of the line processes and the centroid position of a third region formed by two of the pixel mixture unit areas which is processed at the same time with the second region and is placed adjacent to the second region in the second direction. With such a structure, centroid correction of a pixel signal output from the solid state imaging device is readily achieved, and the frame lag in a moving picture can be reduced. In the solid state imaging device of the present invention, preferably, the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. In this case, a color filter arrangement of the solid state imaging element may be a combination of Bayer arrangements of 2 rows×2 columns; the pixel addition means may include a first-direction transfer stage for adding together electric charges of the plurality of pixels in the first direction in each of the pixel mixture unit areas and a second-direction transfer stage for adding together the electric charges obtained by the addition in the first-direction transfer stage in the second direction; and the electric charges obtained by the addition in the second-direction transfer stage may be pixel signals for complementary color filter arrangement display. Alternatively, a color filter arrangement of the solid state imaging element may be a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. In the solid state imaging device of the present invention, preferably, the pixel addition means includes a first-direction transfer stage and a second-direction transfer stage, the first-direction transfer stage including a plurality of CCDs which transfer the electric charges of the pixels in the first direction, the second-direction transfer stage including a plurality of CCDs which transfer the electric charges transferred from the first-direction transfer stage in the second direction. With such a structure, the process of adding together the electric charges of pixels with CCDs can be realized. In this case, preferably, the second-direction transfer stage alternately includes a storage region which includes a first gate and retains an electric charge and a barrier region which includes a second gate and functions as a barrier against transfer of electric charges; and the first gate and the second gate are electrically separated to receive separate biases. With such a structure, the electric charges of the pixels in the second-direction transfer stage can be transferred not only in the forward direction but also in the reverse direction. Accordingly, the pixel addition process can be quickly performed. A method of the present invention for driving a solid state imaging device which includes a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction, comprises the steps of: (a) adding together electric charges of pixels included in each of the pixel mixture unit areas and transferring the added electric charges in the first direction; (b) adding together electric charges of pixels from a plurality of pixel mixture unit areas while the electric charges added and transferred in the first direction at step (a) are transferred in the second direction; and (c) alternately outputting signals which relates to the electric charges added together at step (b) in first and second fields as signals for interlaced scanning. According to the solid state imaging device driving method of the present invention, a video signal can be read with high speed without thinning pixels to be read. Therefore, signals of all the pixels can be output without abandonment and, accordingly, the sensitivity of the imaging element is greatly improved. Further, aliasing components derived from high frequency components in a low frequency range are greatly reduced. Therefore, false signals are greatly suppressed in both the brightness signal and chromaticity signal. As a result, the image quality improves. In the solid state imaging device driving method of the present invention, preferably, the pixel mixture unit areas overlap one another in the first and second directions to constitute an arrangement which has a two-dimensional repetition. In the solid state imaging device driving method of the present invention, preferably, at step (a), electric charges of pixels included in one pixel mixture unit area are added together in the first direction; and at step (b), the electric charges added together in the first direction at step (a) are added together in the second direction. Preferably, at step (b), a line process of adding together in the second direction electric charges of pixels of two pixel mixture unit areas which are adjacent in the first direction is performed over a plurality of stages. In the solid state imaging device driving method of the present invention, preferably, the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. In this case, a color filter arrangement of the solid state imaging element may be a combination of Bayer arrangements of 2 rows×2 columns; and at step (b), electric charges of pixels having different colors in each of the pixel mixture unit areas may be added together to generate a pixel signal for a complementary color filter arrangement. Alternatively, a color filter arrangement of the solid state imaging element may be a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view schematically showing an arrangement of components in a CCD solid state imaging element of a color solid state imaging device according to embodiment 1 of the present invention. FIG. 2 illustrates the procedure of a pixel mixture process for the first field according to embodiment 1. FIG. 3 generally illustrates the pixel mixture in the first field according to embodiment 1. FIG. 4 generally illustrates the pixel mixture in the second field according to embodiment 1. FIG. 5 is a plan view schematically showing an arrangement of components in a CCD solid state imaging element of a color solid state imaging device according to embodiment 2 of the present invention. FIG. 6 illustrates the procedure of a pixel mixture process for the first field according to embodiment 2. FIG. 7 generally illustrates the pixel mixture in the first field according to embodiment 2. FIG. 8 generally illustrates the pixel mixture in the second field according to embodiment 2. FIG. 9 is a plan view schematically showing an arrangement of components in a CCD solid state imaging element of a color solid state imaging device according to embodiment 3 of the present invention. FIG. 10 illustrates the procedure of a pixel mixture process for the first field according to embodiment 3. FIG. 11 generally illustrates the pixel mixture in the first field according to embodiment 3. FIG. 12 generally illustrates the pixel mixture in the second field according to embodiment 3. FIG. 13 is a block diagram showing a structure of a solid state imaging device which is common to embodiments 1 to 3. FIG. 14A is a cross-sectional view of a transfer gate portion in a horizontal transfer stage which is common to the embodiments of the present invention. FIG. 14B is a cross-sectional view of a conventional transfer gate portion. FIG. 14C shows the potential state in a cross section that traverses a p+ layer and a p-type semiconductor layer of the conventional transfer gate portion. FIG. 15A and FIG. 15B show the relationship of the centroid positions in the pixel mixture of the first vertical line and the second vertical line respectively for the first field and the second field in embodiment 1. FIG. 16A and FIG. 16B show the relationship of the centroid in the pixel mixture of the first vertical line and the second vertical line for the first field and the second field, respectively, in embodiment 2. FIG. 17A illustrates the relationship between the centroid positions for pixel mixture in the first vertical line and the centroid positions for pixel mixture in the second vertical line for the example shown in FIGS. 15A and 15B. FIG. 17B illustrates the relationship between the centroid positions for pixel mixture in the first vertical line and the centroid positions for pixel mixture in the second vertical line for the example shown in FIGS. 16A and 16B. FIG. 18 is a block circuit diagram simply showing the structure of a centroid position correction circuit. FIG. 19A illustrates the process of generating a brightness signal by adding together electric charge signals of a pixel mixture unit area for the example shown in FIGS. 15A and 15B. FIG. 19B illustrates the process of generating a brightness signal by adding together electric charge signals of a pixel mixture unit area for the example shown in FIGS. 16A and 16B. FIG. 20A illustrates biases and channel potentials in a forward transfer of electric charges at the transfer gate section of horizontal transfer. FIG. 20B illustrates biases and channel potentials in a reverse transfer of electric charges at the transfer gate section of horizontal transfer. FIG. 21 is a timing chart illustrating variations over time in the biases applied to respective gates for the purpose of achieving the electric charge mixture process shown in FIG. 2 of embodiment 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, examples of a color solid state imaging device of the present invention will be described with reference to the drawings. It should be noted that examples of a CCD solid state imaging element will be described in the following embodiments, but the solid state imaging element may be a MOS type solid state imaging element. Thus, in the following embodiments, “mixture of charges” means one of the operations of adding together the charges. (EMBODIMENT 1) FIG. 1 is a plan view schematically showing an arrangement of components in a CCD solid state imaging element of a color solid state imaging device according to embodiment 1. The solid state imaging element of embodiment 1 includes a large number of pixels 11 arranged in a matrix along the vertical direction (first direction) and the horizontal direction (second direction). Each pixel 11 includes a photoelectric conversion element and a color filter attached over the front face of the photoelectric conversion element. The pixels 11 include B-pixels corresponding to blue filter regions (shown by “B” in FIG. 1), R-pixels corresponding to red filter regions (shown by “R” in FIG. 1), and Gr- and Gb-pixels corresponding to green filter regions (shown by “Gr” and “Gb” in FIG. 1). That is, the solid state imaging element of embodiment 1 has a primary color filter arrangement, especially, a Bayer arrangement structure. Although in actuality the Gr-pixels and Gb-pixels correspond to filter regions of the same color (green), a pixel horizontally sandwiched by R-pixels is shown as a Gr-pixel and a pixel horizontally sandwiched by B-pixels is shown as a Gb-pixel for convenience of illustration. The solid state imaging device of embodiment 1 includes: a 6-phase vertical transfer stage (first-direction transfer stage) 12 (12A, 12B, . . . ) which is formed by connecting gates V1 to V6 in series; a horizontal transfer stage (second-direction transfer stage) W which is formed by connecting 4-phase transfer gate portions W1, W2, . . . , in series, each 4-phase transfer gate portion including gates H1, H2, H3 and H4; an output amplifier 14 for outputting electric charges accumulated in the horizontal transfer stage W; and a vertical-horizontal transfer linking portion 15 at the end stage of vertical transfer which has the gates capable of being independently driven (gates V3, V3R, V3L, V5, V5R, and V5L). The vertical transfer stage 12, the vertical-horizontal transfer linking portion 15, and the horizontal transfer stage W constitute means for performing a pixel mixture process for the first field and a pixel mixture process for the second field, which will be described later. Further, the output amplifier 14 functions as means for outputting a signal of a pixel which is obtained through the pixel mixture processes for the first and second fields as a signal for interlaced scanning. Herein, the odd-numbered gates, e.g., gates V1, V3, . . . of the transfer stages 12A, 12B, . . . are each connected to a photoelectric conversion element of a corresponding pixel to read an electric charge from the pixel. The read electric charge is transferred by the gates V1 to V6. The gates H1 and H3 of the transfer gate portions W1, W2, . . . in the horizontal transfer stage W has the function of retaining an electric charge transferred from the vertical-horizontal transfer linking portion 15. The gates H2 and H4 function as a barrier against the movement of the electric charge through the gates H1 and H3. Herein, as will be described later, the gates H1, H2, H3 and H4 of the transfer gate portions W1, W2, . . . in the horizontal transfer stage W are independently wired. The pixels 11 arranged in a matrix are grouped into a large number of pixel mixture unit areas which overlap one another. In embodiment 1, the pixels 11 are grouped. into basic units A of pixel mixture areas, each of which is formed by 5'5 pixels. The color of a filter portion corresponding to a pixel at the center of each pixel mixture unit area A represents the mixed color in each pixel mixture unit area. In the example of embodiment 1, each pixel mixture unit area is 5 rows×5 columns. As shown in FIG. 1, in embodiment 1, the pixel mixture unit areas of the first field include a pixel mixture unit area A1 of Gb, a pixel mixture unit area A2 of B, a pixel mixture unit area A3 of Gr, a pixel mixture unit area A4 of R, a pixel mixture unit area A5 of Gb, a pixel mixture unit area A6 of B, a pixel mixture unit area A7 of R, and a pixel mixture unit area A8 of Gr. In the specification of the present application, the term “pixel mixture unit area” is defined so as to include a unit area in which addition of electric charges in a MOS solid state imaging element is performed. In the example described herein, neighboring pixel mixture unit areas overlap one another by two pixels both horizontally and vertically. Although not shown in FIG. 1, the pixel mixture unit areas A1 to A8 repeatedly occur while overlapping one another both vertically and horizontally. [Pixel Mixture in First Field] Next, the procedure of a pixel mixture process for the first field according to embodiment 1 is described with the example of FIG. 1, where pixels in each of the pixel mixture unit areas A1 to A8 are mixed, in conjunction with FIG. 2. Process of Mixing Electric Charges of Pixels in Pixel Mixture Unit Area At the first step, a read pulse is applied to the gate V3 of the vertical transfer stage 12, whereby electric charges are read from the uppermost row of each pixel mixture unit area. The electric charges are transferred to the gate V1. Then, a read pulse is applied to the gate V1, whereby electric charges are read from the center of the pixel mixture unit area. The read electric charges are mixed with the electric charges previously read from the uppermost row. The mixed electric charges of the two pixels are transferred from the gate V1 to the gate V5. Then, a read pulse is applied to the gate V5, whereby electric charges of the three pixels are mixed. Thus, the electric charges of the three pixels vertically aligned in the pixel mixture unit area are mixed as described above. In the example described herein, mixture of electric charges of the vertically-aligned three pixels is performed at the same time in the pixel mixture unit areas A1 to A8. It should be noted that there are many methods for mixing electric charges of the vertically-aligned three pixels other than those described in embodiments 1 to 3. As a matter of course, any of the other methods may be used in the present invention. The thus-mixed electric charges of the three pixels are vertically transferred on a sequential basis and accumulated in the gates of the vertical-horizontal transfer linking portion 15 that is placed between the vertical transfer stage 12 and the horizontal transfer stage W. FIG. 2 illustrates the procedure of mixing electric charges from two pixel mixture unit areas on a line by line basis in the horizontal transfer stage W after the electric charges from the three pixels have been mixed in the vertical transfer stage 12 for each pixel mixture unit area and transferred to the horizontal transfer stage W in the first field. The output of one horizontal line corresponds to the outputs of the three vertical lines. Therefore, FIG. 2 illustrates the procedure of transferring the electric charges mixed in two pixel mixture areas on a three-vertical-line by three-vertical-line basis. In FIG. 2, the horizontal axis represents the position of the transfer gate portions in the horizontal transfer stage W, and the vertical axis represents the time. Hereinafter, the pixel mixture process in each line is described with reference to FIG. 2. It should be noted that FIG. 2, and FIGS. 6 and 10 which will be described later, only show electric charges extracted from the vertical-horizontal transfer linking portion 15 to the horizontal transfer stage W. However, in the second and subsequent columns of each line, the electric charges transferred in the horizontal transfer stage W and the electric charges extracted from the vertical-horizontal transfer linking portion 15 to the horizontal transfer stage W are sequentially mixed. In embodiment 1, the vertical transfer stage 12 and the vertical-horizontal transfer linking portion 15 are controlled by a common bias signal, whereas the vertical transfer stage 12 and the vertical-horizontal transfer linking portion 15 are separately controlled in embodiments 2 and 3. In embodiment 1, although the mixture process of electric charges C1c to C6c, C1d to C6d, D1c to D6c, D1d to D6d, E1c to E6c, E1d to E6d is only described, the mixture process is also performed on the other electric charges, e.g., electric charges C1e to C6e, D1e to D6e, E1e to E6e, and the like, as shown in FIG. 2. Process in First Line At the first step, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15D and 15G) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 (each gate H1) and retained as electric charges C1c and C1d. Hereinafter, FIG. 2 only shows the electric charges extracted from the vertical transfer stages but, in actuality, the electric charges extracted from the vertical lines are sequentially mixed. Then, electric charges C1c and C1d are transferred in the reverse direction (direction away from the output amplifier 14) by two stages (i.e., two stages of the transfer gate portions each consisting of the gates H1 to H4) and, thereafter, the electric charges mixed in the vertical transfer stages (15F and 151) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges C1c+C2c and C1d+C2d. Electric charges C1c+C2c and C1d+C2d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15H and 15K) including the gates V3 and V5 are extracted to the transfer gate portions W8 and W11 and retained as electric charges C1c+C2c+C3c and C1d+C2d+C3d. Electric charge C1c+C2c+C3c is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area A1. Electric charge C1d+C2d+C3d is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area A2. Hereinafter, the subsequent steps of the mixture process on electric charges C1c+C2c+C3c and C1d+C2d+C3d are only described. Electric charges C1c+C2c+C3c and C1d+C2d+C3d are transferred in the forward direction (direction toward the output amplifier 14) by one stage, and then, electric charges mixed in the vertical transfer stages (15G and 15J) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W7 and W10 and retained as electric charges C1c+C2c+C3c+C4c and C1d+C2d+C3d+C4d. Electric charges C1c+C2c+C3c+C4c and C1d+C2d+C3d+C4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15C and 15F) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W3 and W6 and retained as electric charges C1c+C2c+C3c+C4c+C5c and C1d+C2d+C3d+C4d+C5d. Electric charges C1c+C2c+C3c+C4c+C5c and C1d+C2d+C3d+C4d+C5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15E and 15H) including the gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges C1c+C2c+C3c+C4c+C5c+C6c and C1d+C2d+C3d+C4d+C5d+C6d. Electric charge C4c+C5c+C6c is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area A3. Electric charge C1c+C2c+C3c+C4c+C5c+C6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A1 and A3, which is output as electric charge CTc. Electric charge C4d+C5d+C6d is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area A4. Electric charge C1d+C2d+C3d+C4d+C5d+C6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A2 and A4, which is output as electric charge CTd. Process in Second Line At the first step, output electric charges CTc and CTd generated in the electric charge mixing process for the first line are transferred in the forward direction by two stages and retained in the transfer gate portions W3 and W6. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15D and 15G) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 (each gate H1) and retained as electric charges D1c and D1d. Thereafter, output electric charges CTc and CTd generated in the process in the first line are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the second line. Then, electric charges D1c and D1d are transferred in the reverse direction by two stages and, thereafter, the electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges D1c+D2c and D1d+D2d. Electric charges D1c+D2c and D1d+D2d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges D1c+D2c+D3c and D1d+D2d+D3d. Electric charge D1c+D2c+D3c is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area A5. Electric charge D1d+D2d+D3d is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area A6. Hereinafter, the subsequent steps of the mixture process on electric charges D1c+D2c+D3c and D1d+D2d+D3d are only described. Electric charges D1c+D2c+D3c and D1d+D2d+D3d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15D and 15G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges D1c+D2c+D3c+D4c and D1d+D2d+D3d+D4d. Electric charges D1c+D2c+D3c+D4c and D1d+D2d+D3d+D4d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges D1c+D2c+D3c+D4c+D5c and D1d+D2d+D3d+D4d+D5d. Electric charges D1c+D2c+D3c+D4c+D5c and D1d+D2d+D3d+D4d+D5d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges D1c+D2c+D3c+D4c+D5c+D6c and D1d+D2d+D3d+D4d+D5d+D6d. Electric charge D4c+D5c+D6c is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area A7. Electric charge D1c+D2c+D3c+D4c+D5c+D6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A5 and A7, which is output as electric charge DTc. Electric charge D4d+D5d+D6d is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area A8. Electric charge D1d+D2d+D3d+D4d+D5d+D6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A6 and A8, which is output as electric charge DTd. Output electric charges CTc and CTd generated in the electric charge mixing process for the first line are retained at positions shifted in the forward direction by one stage from the positions where output electric charges DTc and DTd generated in the electric charge mixing process for the second line are retained. Process in Third Line At the first step, output electric charges CTc, CTd, DTc and DTd generated in the electric charge mixing process for the first and second lines are transferred in the forward direction by two stages and retained in the transfer gate portions W-1 (not shown in FIG. 2: present at a position shifted by two stages in the forward direction from the transfer gate portion W1), W2, W0 (not shown in FIG. 2: present at a position shifted by one stage in the forward direction from the transfer gate portion W1) and W3. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15A and 15D) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W1 and W4 (each gate HI) and retained as electric charges E1c and E1d. Thereafter, output electric charges CTc, CTd, DTc and DTd generated in the electric charge mixing process for the first and second lines are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the third line. Then, electric charges E1c and E1d are transferred in the reverse direction by two stages and, thereafter, the electric charges mixed in the vertical transfer stages (15C and 15F) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W3 and W6 and retained as electric charges E1c+E2c and E1d+E2d. Electric charges E1c+E2c and E1d+E2d are transferred in the forward direction by two stages, and then, electric charges mixed in the vertical transfer stages (15E and 15H) including the gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges E1c+E2c+E3c and E1d+E2d+E3d. Electric charge E1c+E2c+E3c is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area A1. Electric charge E1d+E2d+E3d is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area A2. Hereinafter, the subsequent steps of the mixture process on electric charges E1c+E2c+E3c and E1d+E2d+E3d are only described. Electric charges E1c+E2c+E3c and E1d+E2d+E3d are transferred in the forward direction by one stage, and then, electric charges mixed in the vertical transfer stages (15D and 15G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges E1c+E2c+E3c+E4c and E1d+E2d+E3d+E4d. Electric charges E1c+E2c+E3c+E4c and E1d+E2d+E3d+E4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15X (not shown in FIG. 2: neighboring stage of the vertical transfer stage 15A at the forward direction side) and 15C) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W0 (not shown in FIG. 2: neighboring transfer gate portion of the transfer gate portion W1 at the forward direction side) and W3 and retained as electric charges E1c+E2c+E3c+E4c+E5c and E1d+E2d+E3d+E4d+E5d. Electric charges E1c+E2c+E3c+E4c+E5c and E1d+E2d+E3d+E4d+E5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges E1c+E2c+E3c+E4c+E5c+E6c and E1d+E2d+E3d+E4d+E5d+E6d. Electric charge E4c+E5c+E6c is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area A3. Electric charge E1c+E2c+E3c+E4c+E5c+E6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A1 and A3, which is output as electric charge ETc. Electric charge E4c+E5c+E6c is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area A4. Electric charge E1c+E2c+E3c+E4c+E5c+E6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas A2 and A4, which is output as electric charge ETd. At the time when the process in the third line is completed, electric charges CTc (placed in the transfer gate portion W0 but not shown in FIG. 2), DTc, ETc, CTd, DTd, ETc, CTd, DTd, ETd, CTe, DTe, ETe, CTf, DTf, ETf . . . are retained in the transfer gate portions W0 (not shown in FIG. 2: neighboring transfer gate portion of the transfer gate portion W1 at the forward direction side), W1, W2, W3, W4, W5, W6, W7, W8, W9, W10, W11, W12 . . . of the horizontal transfer stage W. The electric charges are sequentially output from the output amplifier 14 to the outside. Output electric charge CTc is converted to an electric charge of a G-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. Output electric charge DTc is converted to an electric charge of a Ye-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a R-pixel of primary color filter arrangement display. Output electric charge ETc is converted to an electric charge of a G-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. Output electric charge CTd is converted to an electric charge of a Mg-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a R-pixel of primary color filter arrangement display. Output electric charge DTd is converted to an electric charge of a Cy-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. Output electric charge ETd is converted to an electric charge of a Mg-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a R-pixel of primary color filter arrangement display. In the above process of mixing electric charges of pixels, a feature of embodiment 1 resides in that electric charges are transferred not only in the forward direction but also in the reverse direction in the horizontal transfer stage W. Thus, as will be described later in detail, in embodiment 1, gate bias wires of the gates H1 to H4 which are charge transfer devices (e.g., CCD) placed in the horizontal transfer stage are separate from each other. FIG. 3 illustrates a general procedure of pixel mixture in the first field shown in FIGS. 1 and 2. In FIG. 3, only a color filter pattern is shown while illustration of gates is omitted. As apparent from FIG. 3 and the descriptions provided above, in the process on the first line and third line of the first field, all of the electric charges of Gb-pixels in the pixel mixture unit area A1 (9 Gb-pixels) and all of the electric charges of Gr-pixels in the pixel mixture unit area A3 (9 Gr-pixels) are mixed to generate an electric charge of a G-pixel used in complementary color filter arrangement display (output electric charges CTc and ETc). Meanwhile, all of the electric charges of B-pixels in the pixel mixture unit area A2 (9 B-pixels) and all of the electric charges of R-pixels in the pixel mixture unit area A4 (9 R-pixels) are mixed to generate an electric charge of a Mg-pixel used in complementary color filter arrangement display (output electric charges CTd and ETd). In the process on the second line of the first field, all of the electric charges of Gb-pixels in the pixel mixture unit area A5 (9 Gb-pixels) and all of the electric charges of R-pixels in the pixel mixture unit area A7 (9 R-pixels) are mixed to generate an electric charge of a Ye-pixel used in complementary color filter arrangement display (output electric charge DTc). Meanwhile, all of the electric charges of B-pixels in the pixel mixture unit area A6 (9 B-pixels) and all of the electric charges of Gr-pixels in the pixel mixture unit area A8 (9 Gr-pixels) are mixed to generate an electric charge of a Cy-pixel used in complementary color filter arrangement display (output electric charge DTd). Then, output electric charge CTc of a G-pixel, output electric charge DTc of a Ye-pixel, output electric charge ETc of a G-pixel, output electric charge CTd of a Mg-pixel, output electric charge DTd of a Cy-pixel, and output electric charge ETd of a Mg-pixel are sequentially output. It should be noted that, also in the pixel mixture process in the first field, the order of charge transfer in the horizontal transfer stage W is not limited to the above, but other examples of the order are possible, and any of them may be used herein instead. [Pixel Mixture in Second Field] Next, pixel mixture for the second field is described. Herein, the drawings corresponding to FIGS. 1 and 2 are omitted. FIG. 4 illustrates a general procedure of pixel mixture in the second field. In FIG. 4, only a color filter pattern is shown while illustration of gates is omitted. As shown in FIG. 4, pixel mixture unit areas A′1, A′2, A′3, A′4, A′5, A′6, A′7 and A′8 in the second field are placed at positions shifted upward by three pixels from pixel mixture unit areas A1, A2, A3, A4, A5, A6, A7 and A8, respectively. The procedure of extracting electric charges of pixels from the pixel mixture unit areas A′1, A′2, A′3, A′4, A′5, A′6, A′7 and A′8 to the vertical transfer stages and performing 3-pixel mixture is the same as that described above as to the first field. The procedure of mixing electric charges in the horizontal transfer stage W is basically the same as that described with FIG. 2. In the last step, 6 electric charges generated by mixture in the first to third lines are output from the output amplifier. In the process on the first line, the electric charges of R-pixels in the pixel mixture unit area A′1 (9 R-pixels) and the electric charges of B-pixels in the pixel mixture unit area A′3 (9 B-pixels) are mixed to generate electric charge C′Tc of a Mg-pixel in complementary color filter arrangement display. Meanwhile, the electric charges of Gr-pixels in the pixel mixture unit area A′2 (9 Gr-pixels) and the electric charge C′Td of Gb-pixels in the pixel mixture unit area A′4 (9 Gb-pixels) are mixed to generate electric charge of a G-pixel used in complementary color filter arrangement display. In the process on the second line, the electric charges of R-pixels in the pixel mixture unit area A′5 (9 R-pixels) and the electric charges of Gb-pixels in the pixel mixture unit area A′7 (9 Gb-pixels) are mixed to generate electric charge D′Tc of a Ye-pixel in complementary color filter arrangement display. Meanwhile, the electric charges of Gr-pixels in the pixel mixture unit area A′6 (9 Gr-pixels) and the electric charges of B-pixels in the pixel mixture unit area A8 (9 B-pixels) are mixed to generate an electric charge D′Td of a Cy-pixel used in complementary color filter arrangement display. In the process on the third line, the electric charges of R-pixels in the pixel mixture unit area A′1 (9 R-pixels) and the electric charges of B-pixels in the pixel mixture unit area A′3 (9 B-pixels) are mixed to generate electric charge E′Tc of a Mg-pixel in complementary color filter arrangement display. Meanwhile, the electric charges of Gr-pixels in the pixel mixture unit area A′2 (9 Gr-pixels) and the electric charges of Gb-pixels in the pixel mixture unit area A′4 (9 Gb-pixels) are mixed to generate an electric charge E′Td of a G-pixel in complementary color filter arrangement display. After electric charges CTc, DTc, ETc, CTd, DTd and ETd generated in the pixel mixture process in the first field are sequentially output to the outside, output electric charge C′Tc of a Mg-pixel, output electric charge D′Tc of a Ye-pixel, output electric charge E′Tc of a Mg-pixel, output electric charge C′Td of a G-pixel, output electric charge D′Td of a Cy-pixel, and output electric charge E′Td of a G-pixel are sequentially output to the outside. That is, the electric charges of the pixels of the first field and the electric charges of the pixels of the second field are transferred from the output amplifier 14 to the outside based on an interlaced scanning format. In embodiment 1 and embodiments 2 and 3 described later, all of the electric charges from the pixels are mixed in each of the pixel mixture process for the first field and the pixel mixture process for the second field. That is, the pixel use rate is 100% in any of the pixel mixture process for the first field and the pixel mixture process for the second field. It should be noted, however, that the effects described below can be achieved even if the pixel use rate is not 100% in the pixel mixture process for the first field or the pixel mixture process for the second field. In the solid state imaging device of embodiment 1, the pixel use rate is 100% in both the pixel mixture process for the first field and the pixel mixture process for the second field, and therefore, a moving picture with a small frame lag can be obtained with no increase in the amount of electric charges of pixels. As a result, a moving picture suitable to various systems based on the interlaced scanning format can be output. In a general solid state imaging device, a sill image is subjected to a normal process and displayed based on a primary color filter arrangement (Bayer arrangement), and only a moving picture is subjected to the pixel mixture process of embodiment 1 or embodiment 2 which will be described later. (EMBODIMENT 2) FIG. 5 is a plan view schematically showing an arrangement of components in a CCD solid stage imaging element of a color solid state imaging device according to embodiment 2. The structure of the solid state imaging element is the same as that described in embodiment 1. As shown in FIG. 5, the pixels 11 arranged in a matrix are grouped into pixel mixture unit areas according to the method for processing captured image data. In embodiment 1, the pixels 11 are grouped into basic units F of pixel mixture areas, each of which is formed by 5'5 pixels. The color of a filter portion corresponding to a pixel at the center of each pixel mixture unit area F represents the mixed color in each pixel mixture unit area. In the example of embodiment 2, each pixel mixture unit area is 5 rows×5 columns. In embodiment 2, the pixel mixture unit areas of the first field include a pixel mixture unit area F1 of B, a pixel mixture unit area F2 of Gb, a pixel mixture unit area F3 of R, a pixel mixture unit area F4 of Gr, a pixel mixture unit area F5 of Gb, a pixel mixture unit area F6 of B, a pixel mixture unit area F7 of R, and a pixel mixture unit area F8 of Gr. In the example described herein, neighboring pixel mixture unit areas overlap one another by two pixels both horizontally and vertically. Although not shown in FIG. 5, the pixel mixture unit areas F1 to F8 repeatedly occur while overlapping one another both vertically and horizontally. In embodiment 2, the structures of vertical transfer stages 12 (12A, 12B, . . .) and the horizontal transfer stage W are the same as those described in embodiment 1. It should be noted, however, that the vertical transfer stages 12 and the vertical-horizontal transfer linking portions 15 are separately controlled in embodiment 2. [Pixel Mixture in First Field] In embodiment 2, a method which is basically the same as that described in embodiment 1 is used to extract electric charges of the pixels of the pixel mixture unit areas F1 to F8 to the gates of the vertical transfer stages, downwardly transfer the extracted electric charges, and mix the electric charges on a three-pixel by three-pixel basis, only except that different numbers are assigned to the vertical transfer stages from which the electric charges of the pixels of the pixel mixture unit areas F1 to F8 are extracted. Resultant mixed electric charges are transferred to the vertical-horizontal transfer linking portion 15. The procedures of the transfer and mixture are the same as those described in embodiment 1, and therefore, the descriptions thereof are herein omitted. FIG. 6 illustrates the procedure of mixing electric charges within 8 pixel mixture unit areas in the first field. In FIG. 6, the horizontal axis represents the position of the transfer gate portions in the horizontal transfer stage W, and the vertical axis represents the time. In embodiment 2, only the processes of mixing electric charges C1c to C6c, C1d to C6d, D1c to D6c, D1d to D6d, E1c to E6c, and E1d to E6d are described. However, in actuality, the other electric charges, e.g., electric charges C1e to C6e, D1e to D6e, E1e to E6e, are also mixed through the same procedure as shown in FIG. 6. Process in First Line At the first step, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15D and 15G) that include the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W3 and W6 (each gate H1) and retained as electric charges C1c and C1d. Hereinafter, FIG. 6 only shows the electric charges extracted from the vertical transfer stages but, in actuality, the electric charges extracted from the vertical lines are sequentially mixed. Then, electric charges C1c and C1d are transferred in the reverse direction by two stages (i.e., two stages of the transfer gate portions each consisting of the gates H1 to H4) and, thereafter, the electric charges mixed in the vertical transfer stages (15E and 15H) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges C1c+C2c and C1d+C2d. Electric charges C1c+C2c and C1d+C2d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15H and 15K) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W7 and W10 and retained as electric charges C1c+C2c+C3c and C1d+C2d+C3 d. Electric charge C1c+C2c+C3c is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area F1. Electric charge C1d+C2d+C3d is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area F2. Hereinafter, the subsequent steps of the mixture process on electric charges C1c+C2c+C3c and C1d+C2d+C3d are only described. Electric charges C1c+C2c+C3c and C1d+C2d+C3d are transferred in the forward direction by one stage, and then, electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges C1c+C2c+C3c+C4c and C1d+C2d+C3d+C4d. Electric charges C1c+C2c+C3c+C4c and C1d+C2d+C3d+C4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges C1c+C2c+C3c+C4c+C5c and C1d+C2d+C3d+C4d+C5d. Electric charges C1c+C2c+C3c+C4c+C5c and C1d+C2d+C3d+C4d+C5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15D and 15G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges C1c+C2c+C3c+C4c+C5c+C6c and C1d+C2d+C3d+C4d+C5d+C6d. Electric charge C4c+C5c+C6c is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area F3. Electric charge C1c+C2c+C3c+C4c+C5c+C6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F1 and F3, which is output as electric charge CTc. Electric charge C4d+C5d+C6d is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area F4. Electric charge C1d+C2d+C3d+C4d+C5d+C6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F2 and F4, which is output as electric charge CTd. Process in Second Line At the first step, output electric charges CTc and CTd generated in the electric charge mixing process for the first line are transferred in the forward direction by one stage and retained in the transfer gate portions W3 and W6. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15D and 15G) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 (each gate H1) and retained as electric charges D1c and D1d. Thereafter, output electric charges CTc and CTd generated in the process in the first line are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the second line. Then, electric charges D1c and D1d are transferred in the reverse direction by two stages and, thereafter, the electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges D1c+D2c and D1d+D2d. Electric charges D1c+D2c and D1d+D2d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges D1c+D2c+D3c and D1d+D2d+D3d. Electric charge D1c+D2c+D3c is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area F5. Electric charge D1d+D2d+D3d is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area F6. Hereinafter, the subsequent steps of the mixture process on electric charges D1c+D2c+D3c and D1d+D2d+D3d are only described. Electric charges D1c+D2c+D3c and D1d+D2d+D3d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15D and 15G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges D1c+D2c+D3c+D4c and D1d+D2d+D3d+D4d. Electric charges D1c+D2c+D3c+D4c and D1d+D2d+D3d+D4d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges D1c+D2c+D3c+D4c+D5c and D1d+D2d+D3d+D4d+D5d. Electric charges D1c+D2c+D3c+D4c+D5c and D1d+D2d+D3d+D4d+D5d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges D1c+D2c+D3c+D4c+D5c+D6c and D1d+D2d+D3d+D4d+D5d+D6d. Electric charge D4c+D5c+D6c is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area F7. Electric charge D1c+D2c+D3c+D4c+D5c+D6cis the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F5 and F7, which is output as electric charge DTc. Electric charge D4d+D5d+D6d is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area F8. Electric charge D1d+D2d+D3d+D4d+D5d+D6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F6 and F8, which is output as electric charge DTd. Process in Third Line At the first step, output electric charges CTc, CTd, DTc and DTd generated in the electric charge mixing process for the first and second lines are retained in the transfer gate portions W1, W4, W2 and W5, respectively. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 15, electric charges mixed in the vertical transfer stages (15C and 15F) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W3 and W6 (each gate H1) and retained as electric charges E1c and E1d. Thereafter, output electric charges CTc, CTd, DTc and DTd generated in the electric charge mixing process for the first and second lines are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the third line. Then, electric charges E1c and E1d are transferred in the reverse direction by two stages (i.e., two stages of the transfer gate portions each consisting of the gates H1 to H4) and, thereafter, the electric charges mixed in the vertical transfer stages (15E and 15H) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges E1c+E2c and E1d+E2d. Electric charges E1c+E2c and E1d+E2d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15G and 15J) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W7 and W10 and retained as electric charges E1c+E2c+E3c and E1d+E2d+E3d. Electric charge E1c+E2c+E3c is the mixture of the electric charges from 9 B-pixels in the pixel mixture unit area F1. Electric charge E1d+E2d+E3d is the mixture of the electric charges from 9 Gb-pixels in the pixel mixture unit area F2. Hereinafter, the subsequent steps of the mixture process on electric charges E1c+E2c+E3c and E1d+E2d+E3d are only described. Electric charges E1c+E2c+E3c and E1d+E2d+E3d are transferred in the forward direction by one stage, and then, electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges E1c+E2c+E3c+E4c and E1d+E2d+E3d+E4d. Electric charges E1c+E2c+E3c+E4c and E1d+E2d+E3d+E4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (15B and 15E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges E1c+E2c+E3c+E4c+E5c and E1d+E2d+E3d+E4d+E5d. Electric charges E1c+E2c+E3c+E4c+E5c and E1d+E2d+E3d+E4d+E5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15D and 15G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges E1c+E2c+E3c+E4c+E5c+E6c and E1d+E2d+E3 d+E4d+E5 d+E6d. Electric charge E4c+E5c+E6c is the mixture of the electric charges from 9 R-pixels in the pixel mixture unit area F3. Electric charge E1c+E2c+E3c+E4c+E5c+E6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F1 and F3, which is output as electric charge ETc. Electric charge E4c+E5c+E6c is the mixture of the electric charges from 9 Gr-pixels in the pixel mixture unit area F4. Electric charge E1c+E2c+E3c+E4c+E5c+E6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas F2 and F4, which is output as electric charge ETd. At the time when the process in the third line is completed, the electric charges are transferred in the forward direction by two stages, so that output electric charges CTc (placed in the transfer gate portion W0 but not shown in FIG. 6), DTc, ETc, CTd, DTd, ETd, CTe, DTe, ETe, CTf, DTf, ETf . . . are retained in the transfer gate portions W0 (not shown in FIG. 6: neighboring transfer gate portion of the transfer gate portion W1 at the forward direction side), W1, W2, W3, W4, W5, W6, W7, W8, W9, W10, W11, W12 . . . of the horizontal transfer stage W. These electric charges are sequentially output from the output amplifier 14 to the outside. Output electric charge CTc is converted to an electric charge of a Mg-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a R-pixel of primary color filter arrangement display. Output electric charge DTc is converted to an electric charge of a Ye-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a R-pixel of primary color filter arrangement display. Output electric charge ETc is converted to an electric charge of a Mg-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a R-pixel of primary color filter arrangement display. Output electric charge CTd is converted to an electric charge of a G-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. Output electric charge DTd is converted to an electric charge of a Cy-pixel of complementary color filter arrangement display by mixture of an electric charge of a B-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. Output electric charge ETd is converted to an electric charge of a G-pixel of complementary color filter arrangement display by mixture of an electric charge of a Gb-pixel and an electric charge of a Gr-pixel of primary color filter arrangement display. In the above process of mixing electric charges of pixels, a feature of embodiment 2 resides in that electric charges are transferred not only in the forward direction but also in the reverse direction in the horizontal transfer stage W. Thus, as will be described later in detail, in embodiment 1, gate bias wires of the gates H1 to H4 which are charge transfer devices (e.g., CCD) placed in the horizontal transfer stage are separate from each other. [Pixel Mixture in Second Field] Next, pixel mixture for the second field is described. Herein, the drawings corresponding to FIGS. 5 and 6 are omitted. FIG. 8 illustrates a general procedure of pixel mixture in the second field. In FIG. 8, only a color filter pattern is shown while illustration of gates is omitted. As shown in FIG. 8, pixel mixture unit areas F′1, F′2, F′3, F′4, F′5, F′6, F′7 and F′8 in the second field are placed at positions shifted upward by three pixels from pixel mixture unit areas F1, F2, F3, F4, F5, F6, F7 and F8, respectively. The procedure of extracting electric charges of pixels from the pixel mixture unit areas F′1, F′2, F′3, F′4, F′5, F′6, F′7 and F′8 to the vertical transfer stages 12 and performing 3-pixel mixture in the gates at the lowermost part is the same as that described above as to the first field. The procedure of mixing electric charges in the horizontal transfer stage W is basically the same as that described with FIG. 6. In the last step, 6 electric charges generated by mixture in the first to third lines are output from the output amplifier. As apparent from FIG. 8 and the descriptions provided above, in the process on the first line and third line of the second field, all of the electric charges of Gr-pixels in the pixel mixture unit area F′1 (9 Gr-pixels) and all of the electric charges of Gb-pixels in the pixel mixture unit area F′3 (9 Gb-pixels) are mixed to generate an electric charge of a G-pixel used in complementary color filter arrangement display (output electric charges C′Tc and E′Tc). Meanwhile, all of the electric charges of R-pixels in the pixel mixture unit area F′2 (9 R-pixels) and all of the electric charges of B-pixels in the pixel mixture unit area F′4 (9 B-pixels) are mixed to generate an electric charge of a Mg-pixel used in complementary color filter arrangement display (output electric charges C′Td and E′Td). In the process on the second line of the second field, all of the electric charges of R-pixels in the pixel mixture unit area F′5 (9 R-pixels) and all of the electric charges of Gb-pixels in the pixel mixture unit area F′7 (9 Gb-pixels) are mixed to generate an electric charge of a Ye-pixel used in complementary color filter arrangement display (output electric charge D′Tc). Meanwhile, all of the electric charges of Gr-pixels in the pixel mixture unit area F′6 (9 Gr-pixels) and all of the electric charges of B-pixels in the pixel mixture unit area F′8 (9 B-pixels) are mixed to generate an electric charge of a Cy-pixel used in complementary color filter arrangement display (output electric charge D′Td). After electric charges CTc, DTc, ETc, CTd, DTd and ETd generated in the pixel mixture process in the first field are sequentially output to the outside, output electric charge C′Tc of a G-pixel, output electric charge D′Tc of a Ye-pixel, output electric charge E′Tc of a G-pixel, output electric charge C′Td of a Mg-pixel, output electric charge D′Td of a Cy-pixel, and output electric charge E′Td of a Mg-pixel are sequentially output to the outside. That is, the electric charges of the pixels of the first field and the electric charges of the pixels of the second field are transferred from the output amplifier 14 to the outside based on an interlaced scanning format. In the solid state imaging device of embodiment 2, the pixel use rate is 100% in both the pixel mixture process for the first field and the pixel mixture process for the second field, and therefore, a moving picture with a small frame lag can be obtained with no increase in the amount of electric charges of pixels. As a result, a moving picture suitable to various systems based on the interlaced scanning format can be output. (EMBODIMENT 3) FIG. 9 is a plan view schematically showing an arrangement of components in a CCD solid state imaging element of a color solid state imaging device according to embodiment 3. The solid state imaging element of embodiment 3 includes a large number of pixels 51 arranged in a matrix. Each pixel 51 includes a photoelectric conversion element and a color filter attached over the front face of the photoelectric conversion element. The pixels 51 include G-pixels corresponding to green filter regions (shown by “G” in FIG. 9), Cy-pixels corresponding to cyan filter regions (shown by “Cy” in FIG. 9), Mg-pixels corresponding to magenta filter regions (shown by “Mg” in FIG. 9), and Ye-pixels corresponding to yellow filter regions (shown by “Ye” in FIG. 9). That is, the solid state imaging element of embodiment 3 has a complementary mosaic arrangement structure. The solid state imaging device of embodiment 3 includes: a 6-phase vertical transfer stage (first-direction transfer stage) 52 (52A, 52B, . . . ) which is formed by connecting gates V1 to V6 in series; a horizontal transfer stage (second-direction transfer stage) W which is formed by connecting 4-phase transfer gate portions W1, W2, . . . , in series, each 4-phase transfer gate portion including gates H1, H2, H3 and H4; an output amplifier 54 for outputting electric charges accumulated in the horizontal transfer stage W; and a vertical-horizontal transfer linking portion 55 at the end stage of vertical transfer which has the gates capable of being independently driven (gates V3, V3R, V3L, V5, V5R, and V5L). The vertical transfer stage 52, the vertical-horizontal transfer linking portion 55, and the horizontal transfer stage W constitute means for performing a pixel mixture process for the first field and a pixel mixture process for the second field, which will be described later. Further, the output amplifier 54 functions as means for outputting a signal of a pixel which is obtained through the pixel mixture processes for the first and second fields as a signal for interlaced scanning. Herein, the odd-numbered gates, e.g., gates V1, V3, . . . of the transfer stages 52A, 52B, . . . are each connected to a photoelectric conversion element of a corresponding pixel to read an electric charge from the pixel. The read electric charge is transferred by the gates V1 to V6. The gates H1 and H3 of the transfer gate portions W1, W2, . . . in the horizontal transfer stage W has the function of retaining an electric charge transferred from the vertical-horizontal transfer linking portion 55. The gates H2 and H4 function as a barrier against the movement of the electric charge through the gates H1 and H3. Herein, as will be described later, the gates H1, H2, H3 and H4 of the transfer gate portions W1, W2, . . . in the horizontal transfer stage W are independently wired. The pixels 51 arranged in a matrix are grouped into pixel mixture unit areas according to the method for processing captured-image data. In embodiment 3, the pixels 11 are grouped into basic units J of pixel mixture areas, each of which is formed by 5'5 pixels. The color of a filter portion corresponding to a pixel at the center of each pixel mixture unit area J represents the mixed color in each pixel mixture unit area. In the example of embodiment 3, each pixel mixture unit area is 5 rows×5 columns. As shown in FIG. 9, in embodiment 3, the pixel mixture unit areas of the first field include a pixel mixture unit area J1 of Mg, a pixel mixture unit area J2 of G, a pixel mixture unit area J3 of Cy, a pixel mixture unit area J4 of Ye, a pixel mixture unit area J5 of G, a pixel mixture unit area J6 of Mg, a pixel mixture unit area J7 of Cy, and a pixel mixture unit area J8 of Ye. In the specification of the present application, the term “pixel mixture unit area” is defined so as to include an unit area in which addition of electric charges in a MOS solid state imaging element is performed. In the example described herein, neighboring pixel mixture unit areas overlap one another by two pixels both horizontally and vertically. Although not shown in FIG. 9, the pixel mixture unit areas J1 to J8 repeatedly occur while overlapping one another both vertically and horizontally. The transfer stages 52A, 52B, . . . perform basic transfer in 6-phase mode. It should be noted that each of the transfer stages 52A, 52B, . . . has independent wires of 12 phases for convenience of pixel mixture. In embodiment 3, the vertical transfer stages 52 and the vertical-horizontal transfer linking portions 55 are separately controlled. [Pixel Mixture in First Field] In embodiment 3, a method which is basically the same as that described in embodiment 1 is used to extract electric charges of the pixels of the pixel mixture unit areas J1 to J8 to the gates of the vertical transfer stages, downwardly transfer the extracted electric charges, and mix the electric charges on a three-pixel by three-pixel basis, only except that different numbers are assigned to the vertical transfer stages from which the electric charges of the pixels of the pixel mixture unit areas J1 to J8 are extracted. The procedures of the transfer and mixture are the same as those described in embodiment 1, and therefore, the descriptions thereof are herein omitted. FIG. 10 illustrates the procedure of mixing electric charges within 8 pixel mixture unit areas in the first field. In FIG. 10, the horizontal axis represents the position of the transfer gate portions in the horizontal transfer stage W, and the vertical axis represents the time. In embodiment 3, only the processes of mixing electric charges X1c to X6c, X1d to X6d, Y1c to Y6c, Y1d to Y6d, Z1c to Z6c and Z1d to Z6d are described. However, in actuality, the other electric charges, e.g., electric charges X1e to X6e, Y1e to Y6e, and Z1e to Z6e are also mixed through the same procedure as shown in FIG. 10. Process in First Line At the first step, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 55, electric charges mixed in the vertical transfer stages (15C and 15F) that include the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W3 and W6 (each gate H1) and retained as electric charges X1c and X1d. Hereinafter, FIG. 10 only shows the electric charges extracted from the vertical transfer stages but, in actuality, the electric charges extracted from the vertical lines are sequentially mixed. Then, electric charges X1c and X1d are transferred in the reverse direction by two stages (i.e., two stages of the transfer gate portions each consisting of the gates H1 to H4) and, thereafter, the electric charges mixed in the vertical transfer stages (55E and 55H) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges X1c+X2c and X1d+X2d. Electric charges X1c+X2c and X1d+X2d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (15G and 15J) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W7 and W10 and retained as electric charges X1c+X2c+X3c and X1d+X2d+X3d. Electric charge X1c+X2c+X3c is the mixture of the electric charges from 9 Mg-pixels in the pixel mixture unit area J1. Electric charge X1d+X2d+X3d is the mixture of the electric charges from 9 G-pixels in the pixel mixture unit area J2. Hereinafter, the subsequent steps of the mixture process on electric charges X1c+X2c+X3c and X1d+X2d+X3d are only described. Electric charges X1c+X2c+X3c and X1d+X2d+X3d are transferred in the forward direction by one stage, and then, electric charges mixed in the vertical transfer stages (55F and 55I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges X1c+X2c+X3c+X4c and X1d+X2d+X3d+X4d. Electric charges X1c+X2c+X3c+X4c and X1d+X2d+X3d+X4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (55B and 55E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges X1c+X2c+X3c+X4c+X5c and X1d+X2d+X3d+X4d+X5d. Electric charges X1c+X2c+X3c+X4c+X5c and X1d+X2d+X3d+X4d+X5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (55D and 55G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges X1c+X2c+X3c+X4c+X5c+X6c and X1d+X2d+X3d+X4d+X5d+X6d. Electric charge X4c+X5c+X6c is the mixture of the electric charges from 9 Cy-pixels in the pixel mixture unit area J3. Electric charge X1c+X2c+X3c+X4c+X5c+X6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J1 and J3, which is output as electric charge XTc. Electric charge X4d+X5d+X6d is the mixture of the electric charges from 9 Ye-pixels in the pixel mixture unit area J4. Electric charge X1d+X2d+X3d+X4d+X5d+X6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J2 and J4, which is output as electric charge XTd. Process in Second Line At the first step, output electric charges XTc and XTd generated in the electric charge mixing process for the first line are transferred in the forward direction by one stage and retained in the transfer gate portions W3 and W6. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 55, electric charges mixed in the vertical transfer stages (55D and 55G) that include the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 (each gate H1) and retained as electric charges V1c and V1d. Thereafter, output electric charges XTc and XTd generated in the process in the first line are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the second line. Then, electric charges D1c and D1d are transferred in the reverse direction by two stages and, thereafter, the electric charges mixed in the vertical transfer stages (55F and 55I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges Y1c+Y2c and Y1d+Y2d. Electric charges Y1c+Y2c and Y1d+Y2d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (55B and 55E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges Y1c+Y2c+Y3c and Y1d+Y2d+Y3d. Electric charge Y1c+Y2c+Y3c is the mixture of the electric charges from 9 G-pixels in the pixel mixture unit area J5. Electric charge Y1d+Y2d+Y3d is the mixture of the electric charges from 9 Mg-pixels in the pixel mixture unit area J6. Hereinafter, the subsequent steps of the mixture process on electric charges Y1c+Y2c+Y3c and Y1d+Y2d+Y3d are only described. Electric charges Y1c+Y2c+Y3c and Y1d+Y2d+Y3d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (55D and 55G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges Y1c+Y2c+Y3c+Y4c and Y1d+Y2d+Y3d+Y4d. Electric charges Y1c+Y2c+Y3c+Y4c and Y1d+Y2d+Y3d+Y4d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (55F and 55I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges Y1c+Y2c+Y3c+Y4c+Y5c and Y1d+Y2d+Y3d+Y4d+Y5d. Electric charges Y1c+Y2c+Y3c+Y4c+Y5c and Y1d+Y2d+Y3d+Y4d+Y5d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (55B and 55E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges Y1c+Y2c+Y3c+Y4c+Y5c+Y6c and Y1d+Y2d+Y3d+Y4d+Y5d+Y6d. Electric charge Y4c+Y5c+Y6c is the mixture of the electric charges from 9 Cy-pixels in the pixel mixture unit area J7. Electric charge Y1c+Y2c+Y3c+Y4c+Y5c+Y6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J5 and J7, which is output as electric charge YTc. Electric charge Y4d+Y5d+Y6d is the mixture of the electric charges from 9 Ye-pixels in the pixel mixture unit area J8. Electric charge Y1d+Y2d+Y3d+Y4d+Y5d+Y6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J6 and J8, which is output as electric charge YTd. Process in Third Line At the first step, output electric charges XTc, XTd, YTc and YTd generated in the electric charge mixing process for the first and second lines are transferred in the forward direction by two stages and retained in the transfer gate portions W1, W4, W2 and W5. Thereafter, among the mixed electric charges from the vertically-aligned three pixels in each pixel mixture unit area which are retained in the gates of the vertical-horizontal transfer linking portion 55, electric charges mixed in the vertical transfer stages (55C and 55F) that include the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W3 and W6 (each gate H1) and retained as electric charges Z1c and Z1d. Thereafter, output electric charges XTc, XTd, YTc and YTd generated in the electric charge mixing process for the first and second lines are transferred together with electric charges which are sequentially mixed and transferred in the electric charge mixture process in the third line. Then, the electric charges Z1c and Z1d are transferred in the reverse direction by two stages (i.e., two stages of the transfer gate portions each consisting of the gates H1 to H4) and, thereafter, the electric charges mixed in the vertical transfer stages (55E and 55H) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W5 and W8 and retained as electric charges Z1c+Z2c and Z1d+Z2d. Electric charges Z1c+Z2c and Z1d+Z2d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (55G and 55J) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W7 and W10 and retained as electric charges Z1c+Z2c+Z3c and Z1d+Z2d+Z3d. Electric charge Z1c+Z2c+Z3c is the mixture of the electric charges from 9 Mg-pixels in the pixel mixture unit area J1. Electric charge Z1d+Z2d+Z3d is the mixture of the electric charges from 9 G-pixels in the pixel mixture unit area J2. Hereinafter, the subsequent steps of the mixture process on electric charges Z1c+Z2c+Z3c and Z1d+Z2d+Z3d are only described. Electric charges Z1c+Z2c+Z3c and Z1d+Z2d+Z3d are transferred in the forward direction by one stage, and then, electric charges mixed in the vertical transfer stages (15F and 15I) including the independently-drivable gates V3R and V5R are extracted to the transfer gate portions W6 and W9 and retained as electric charges Z1c+Z2c+Z3c+Z4c and Z1d+Z2d+Z3d+Z4d. Electric charges Z1c+Z2c+Z3c+Z4c and Z1d+Z2d+Z3d+Z4d are transferred in the forward direction by four stages, and then, electric charges mixed in the vertical transfer stages (55B and 55E) including the independently-drivable gates V3 and V5 are extracted to the transfer gate portions W2 and W5 and retained as electric charges Z1c+Z2c+Z3c+Z4c+Z5c and Z1d+Z2d+Z3d+Z4d+Z5d. Electric charges Z1c+Z2c+Z3c+Z4c+Z5c and Z1d+Z2d+Z3d+Z4d+Z5d are transferred in the reverse direction by two stages, and then, electric charges mixed in the vertical transfer stages (55D and 55G) including the independently-drivable gates V3L and V5L are extracted to the transfer gate portions W4 and W7 and retained as electric charges Z1c+Z2c+Z3c+Z4c+Z5c+Z6c and Z1d+Z2d+Z3d+Z4d+Z5d+Z6d. Electric charge Z4c+Z5c+Z6c is the mixture of the electric charges from 9 Cy-pixels in the pixel mixture unit area J3. Electric charge Z1c+Z2c+Z3c+Z4c+Z5c+Z6c is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J1 and J3, which is output as electric charge ZTc. Electric charge Z4d+Z5d+Z6d is the mixture of the electric charges from 9 Ye-pixels in the pixel mixture unit area J4. Electric charge Z1d+Z2d+Z3d+Z4d+Z5d+Z6d is the mixture of the electric charges from 18 pixels in the pixel mixture unit areas J2 and J4, which is output as electric charge ZTd. At the time when the process in the third line is completed, the electric charges are transferred in the forward direction by two stages, so that output electric charges XTc (placed in the transfer gate portion W0 but not shown in FIG. 10), YTc, ZTc, XTd, YTd, ZTc, XTd, YTd, ZTd, XTe, YTe, ZTe, XTf, YTf, ZTf . . . are retained in the transfer gate portions W0 (not shown in FIG. 10: neighboring transfer gate portion of the transfer gate portion W1 at the forward direction side), W1, W2, W3, W4, W5, W6, W7, W8, W9, W10, W11, W12 . . . of the horizontal transfer stage W. These electric charges are sequentially output from the output amplifier 14 to the outside. Output electric charge XTc is the mixture of electric charges of a Mg-pixel and a Cy-pixel of complementary color filter arrangement display. Output electric charge YTc is the mixture of electric charges of a G-pixel and a Cy-pixel of complementary color filter arrangement display. Output electric charge ZTc is the mixture of electric charges of a Mg-pixel and a Cy-pixel of complementary color filter arrangement display. Output electric charge XTd is the mixture of electric charges of a G-pixel and a Ye-pixel of complementary color filter arrangement display. Output electric charge YTd is the mixture of electric charges of a Mg-pixel and a Ye-pixel of complementary color filter arrangement display. Output electric charge ZTd is the mixture of electric charges of a G-pixel and a Ye-pixel of complementary color filter arrangement display. In the above process of mixing electric charges of pixels, a feature of embodiment 3 resides in that electric charges are transferred not only in the forward direction but also in the reverse direction in the horizontal transfer stage W. Thus, as will be described later in detail, in embodiment 3, gate bias wires of the gates H1 to H14 which are charge transfer devices (e.g., CCD) placed in the horizontal transfer stage are separate from each other. [Pixel Mixture in Second Field] Next, pixel mixture for the second field is described. Herein, the drawings corresponding to FIGS. 9 and 10 are omitted. FIG. 12 illustrates a general procedure of pixel mixture in the second field. In FIG. 12, only a color filter pattern is shown while illustration of gates is omitted. As shown in FIG. 12, pixel mixture unit areas J′1, J′2, J′3, J′4, J′5, J′6, J′7 and J′8 in the second field are placed at positions shifted upward by three pixels from pixel mixture unit areas J1, J2, J3, J4, J5, J6, J7 and J8, respectively. The procedure of extracting electric charges of pixels from the pixel mixture unit areas J′1, J′2, J′3, J′4, J′5, J′6, J′7 and J′8 to the vertical transfer stages 12 and performing 3-pixel mixture in the gates at the lowermost part is the same as that described above as to the first field. The procedure of mixing electric charges in the horizontal transfer stage W is basically the same as that described with FIG. 10. In the last step, 6 electric charges generated by mixture in the first to third lines are output from the output amplifier. As apparent from FIG. 12 and the descriptions provided above, in the process on the first line and third line of the second field, all of the electric charges of Ye-pixels in the pixel mixture unit area J′1 (9 Ye-pixels) and all of the electric charges of G-pixels in the pixel mixture unit area J′3 (9 G-pixels) are mixed (output electric charge Ye+G). Meanwhile, all of the electric charges of Cy-pixels in the pixel mixture unit area J′2 (9 Cy-pixels) and all of the electric charges of Mg-pixels in the pixel mixture unit area J′4 (9 Mg-pixels) are mixed (output electric charge Cy+Mg). In the process on the second line of the second field, all of the electric charges of Cy-pixels in the pixel mixture unit area J′5 (9 Cy-pixels) and all of the electric charges of G-pixels in the pixel mixture unit area J′7 (9 G-pixels) are mixed (output electric charge Cy+G). Meanwhile, all of the electric charges of Ye-pixels in the pixel mixture unit area J′6 (9 Ye-pixels) and all of the electric charges of Mg-pixels in the pixel mixture unit area J′8 (9 Mg-pixels) are mixed (output electric charge Ye+Mg). After electric charges XTc, YTc, ZTc, XTd, YTd and ZTd generated in the pixel mixture process in the first field are sequentially output to the outside, output electric charge X′Tc from Ye and G pixels, output electric charge Y′Tc from Cy and G pixels, output electric charge Z′Tc from Ye and G pixels, output electric charge X′Td from Cy and Mg pixels, output electric charge Y′Td from Mg and Ye pixels, and output electric charge Z′Td from Mg and Cy pixels are sequentially output to the outside. That is, the electric charges of the pixels of the first field and the electric charges of the pixels of the second field are transferred from the output amplifier 14 to the outside based on an interlaced scanning format. In the solid state imaging device of embodiment 3, the pixel use rate is 100% in both the pixel mixture process for the first field and the pixel mixture process for the second field, and therefore, a moving picture with a small frame lag can be obtained with no increase in the amount of electric charges of pixels. As a result, a moving picture suitable to various systems based on the interlaced scanning format can be output. In embodiment 3, a signal obtained after the pixel mixture process is an electric charge signal for a complementary color filter but may be an electric charge signal for a primary color filter. [System of Solid State Imaging Device] FIG. 13 is a block diagram showing a structure of a solid state imaging device which is common to embodiments 1-3. A solid state imaging element 101 is the solid state imaging element described in each embodiment. The solid state imaging element 101 converts received light to an electric signal and outputs the electric signal to a signal conversion section 113. A solid state imaging element driving section 112 outputs a control signal to control the solid state imaging element 101. The signal conversion section 113 receives an electric signal which is an electric charge of each pixel from an output amplifier connected to the horizontal transfer stage of the solid state imaging element 101 and performs correlated double sampling (CDS), auto gain control (AGC) and analog/digital (A/D) conversion on the received electric signal. In the CDS, noise is removed from the electric signal output from the solid state imaging element 101. In the AGC, the output level of the noise-removed signal is adjusted. In the A/D conversion, the level-adjusted solid state image data is converted to a digital signal. The signal conversion section 113 outputs the converted signals for 3 lines at one time to a rearrangement section 115. A sync signal generator (SSG) 114 generates a reference signal which is used for determining drive timings of the solid state imaging element 101 and a signal processing section 119. That is, the SSG 114 determines the timing of a signal which is to be applied to each gate of the vertical transfer stages, the vertical-horizontal transfer linking portions, and the horizontal transfer stages shown in FIG. 1, for example. The SSG 114 outputs to the rearrangement section 115 a reference signal which is used for determining the timing of starting a field (screen) and a timing of starting a horizontal line. A dynamic random access memory (DRAM) 116 stores digital data rearranged by the rearrangement section 115. A DRAM control section 117 reads rearranged data which relates to electric charges of pixels and outputs the read data to an output signal generation section 118. The output signal generation section 118 receives data relating to the electric charge which has passed through the rearrangement block and performs the Y signal process of generating/outputting a brightness signal and the C signal process of generating/outputting a color difference signal. The output signal generation section 118 performs the Y signal process to generate/output a brightness signal, but there is a possibility that an image converted from the data relating to the electric charge of a pixel to a Y signal has deteriorated sharpness. In such a case, the output signal generation section 118 further performs contour correction to emphasize the contour. The rearrangement section 115 performs a rearrangement process on a digital signal output from the signal conversion section 113 according to the reference signal output from the SSG 114. For example, as shown in FIG. 2, the digital signal output from the horizontal transfer section of the solid state imaging element 101 and processed by the signal conversion section 113 corresponds to an one-dimensional arrangement of the signal which relates to the electric charge of a pixel (in FIG. 2, electric charges E6a, C6a, D6a, E6b, C6b and D6b are output in series). The rearrangement process restores the one-dimensional signal into the original two-dimensional arrangement. In the above-described embodiments, a so-called zigzag mixing process is performed, i.e., the pixels of a plurality of pixel mixture unit areas (pixel mixture unit areas A1 to A8), the vertical transfer stages of the central pixels of which are shifted from one another, are mixed. Therefore, in the rearrangement section 115, the centroid is corrected while an image signal is reproduced as will be described later. FIG. 14A shows the potential state in a cross section of a transfer gate portion in the horizontal transfer stage which is a common structure among the embodiments of the present invention. FIG. 14B shows the potential state in a cross section of a conventional transfer gate portion. FIG. 14C shows the potential state in a cross section that traverses a p+ layer 15I and a n-type semiconductor layer 150 of the conventional transfer gate portion. As shown in FIG. 14A, each of the transfer gate portions of the solid state imaging element alternately includes the gates H1 and H3 for retaining electric charges and the gates H2 and H4 for barriers in a series arrangement. Each of the gates Hi and H3 has a polysilicon electrode 153 buried in a dielectric film 152 on a semiconductor substrate. Each of the gates H2 and H4 has an Al electrode 154 which is provided on the dielectric film 152 over the semiconductor substrate. The n-type semiconductor layer 150, which contains n-type impurities of relatively low concentration, exists under the gates H1 and H3 that retain electric charges. The p+layer 151, which contains p-type impurities of high concentration, exists under the barrier gates H2 and H4. A line 157 connected to the Al electrode 154 and a line 158 connected to the polysilicon electrode 153 are separate from each other. In a transfer gate portion of a conventional solid state imaging element, the structures of the gates H1 and H2 and the semiconductor substrates are the same as those shown in FIG. 14A except that the line 157 and the line 158, which receive biases φH1 and φH2 of opposite phases, are connected to each other. As shown in FIG. 14C, in one transfer gate portion, a common bias (φH1 or φH2) is applied to the A1 electrode 154 and the polysilicon electrode 153, and therefore, the potential difference between the n-type semiconductor region 150 under the gate H1 and the p+layer 15I under the gate H2 is substantially constant. Thus, in the case of the potential relationship shown in FIG. 14C, an electric charge is transferred leftward, whereas no electric charge is transferred rightward. In the structure of a CCD according to embodiment 3 of the present invention shown in FIG. 14A, the line 157 connected to the Al electrode 154 and the line 158 connected to the polysilicon electrode 153 are separate from each other, and therefore, the relationship as to the potential levels (high/low) between the n-type semiconductor region 150 under the gate H1 and the p+layer 15I under the gate H2 is inverted from that obtained when a common bias is applied. Thus, it is possible to transfer an electric charge in the reverse direction (rightward in FIG. 14C). Thus, according to embodiment 3, an electric charge can be transferred in the horizontal transfer stage W not only in the forward direction, i.e., the direction toward the output amplifier 14 (or 54), but also in the reverse direction, i.e., the direction away from the output amplifier 14 (or 54). As a result, the control described below is enabled. FIGS. 20A and 20B illustrate biases φH1 to φH4 and the channel potentials obtained when an electric charge is transferred in the forward direction and the reverse direction in transfer gate portions of the horizontal transfer stage. As shown in FIG. 20A, by applying biases such that φH1=φH2, φH3=φH4, and φH1<φH4, the potential of the channel decreases in the order of gate H3, gate H4, gate H1 and gate H2. Therefore, the electric charge is transferred in the forward direction. As shown in FIG. 20B, by applying biases such that φH1=φH4, φH2=φH3, and φH1<φH2, the potential of the channel increases in the order of gate H3, gate H4, gate H1 and gate H2. Therefore, the electric charge is transferred in the reverse direction. FIG. 21 is a timing chart illustrating the variations of biases applied to the gates of the horizontal transfer stage W and the vertical-horizontal transfer linking portion 15 over time. In FIG. 21, in each pulse of the horizontal transfer stage W, the higher end is the L level (0 V) and the lower end is the H level (3.3 V). In each pulse of the vertical-horizontal transfer linking portion 15, the higher end is the L level (−8 V) and the lower end is the H level (0 V). It should be noted that FIG. 21 only shows the pulse shapes of the forward direction transfer for the purpose of clearly illustrating the number of pulses and the number of transfer stages, and the biases are always such that φH1=φH2 and φH3=φH4. In the case of the reverse direction transfer, however, the biases are always such that φH1=φH4 and φH2=φH3, and therefore, the actual pulse shapes are different from those shown in FIG. 21. Although FIG. 21 illustrates an example of a charge mixture process on the first to third lines of the first field in embodiment 1 shown in FIG. 2, the mixture process can be readily achieved even in the mixture processes of the other embodiments by appropriately modifying the biases of the horizontal transfer stage and the vertical-horizontal transfer linking portion. Hereinafter, the relationship between the biases applied in the charge mixture process of FIG. 2 and the charge mixture operation is described with reference to FIG. 21. In the first place, in a period between time t0 and time t1, electric charges retained in the gates V3L and V4 are extracted to the horizontal transfer stage W (electric charges C1b, C1c, C1d and C1e in FIG. 2). After time t1, the pulses of biases φH1 to φH4 which have the level relationship shown in FIG. 20B are supplied twice, whereby the electric charges of the horizontal transfer stage is transferred in the reverse direction by two stages (electric charges C1b, C1c, C1d and C1e in FIG. 2). Thereafter, while biases φH1 to φH4 of the horizontal transfer stage are fixed (i.e., while the electric charges are fixed), the electric charges retained in the gates V3R and V4 are extracted to the horizontal transfer stage W (electric charges C2b, C2c, C2d and C2e in FIG. 2) and mixed with the electric charges transferred in the horizontal transfer stage. Thereafter, during a period from time t2 to time t6, a transfer of electric charges in the reverse direction by two stages, a transfer of electric charges in the forward direction by one stage, a transfer of electric charges in the forward direction by four stages, a transfer of electric charges in the reverse direction by two stage, and the mixture process of the transferred electric charges and electric charges extracted from the vertical-horizontal transfer linking portion are performed through the same operations in the horizontal transfer stage. This process is the electric charge mixture process in the first line shown in FIG. 2. After time t6, the electric charges mixed in the first line (e.g., output electric charges CTc and CTd in embodiment 1) are transferred in the forward direction by two stages to be placed at positions shifted in the forward direction by one stage with respect to the electric charges which are extracted from the vertical-horizontal transfer linking portion at the start of the second line shown in FIG. 2. Then, during a period from time t6 to time t12, a transfer of electric charges in the reverse direction by two stages, a transfer of electric charges in the forward direction by four stages, a transfer of electric charges in the reverse direction by two stage, a transfer of electric charges in the reverse direction by two stage, a transfer of electric charges in the forward direction by four stages, and the mixture process of the transferred electric charges and electric charges extracted from the vertical-horizontal transfer linking portion are performed in the horizontal transfer stage. The process performed during this period is the electric charge mixture process in the second line shown in FIG. 2. In this period, the electric charges mixed in the first line (e.g., output electric charges CTc and CTd in embodiment 1) move one stage ahead of the electric charges mixed in the second line in the forward direction. After time t12, the electric charges mixed in the first and second lines (e.g., output electric charges CTc, CTd, DTc and DTd in embodiment 1) are transferred in the forward direction by two stages to be placed at positions shifted in the forward direction by one stage with respect to the electric charges which are extracted from the vertical-horizontal transfer linking portion at the start of the third line shown in FIG. 2. Then, during a period from time t12 to time t18, a transfer of electric charges in the reverse direction by two stages, a transfer of electric charges in the reverse direction by two stages, a transfer of electric charges in the forward direction by one stage, a transfer of electric charges in the forward direction by four stages, a transfer of electric charges in the reverse direction by two stage, and the mixture process of the transferred electric charges and electric charges extracted from the vertical-horizontal transfer linking portion are performed in the horizontal transfer stage. The process performed during this period is the electric charge mixture process in the third line shown in FIG. 2. In this period, the electric charges mixed in the first and second lines (e.g., output electric charges CTc, CTd, DTc and DTd in embodiment 1) move one stage ahead of the electric charges mixed in the third line in the forward direction. Immediately after time t18, the output electric charges are aligned as shown at the bottom of FIG. 2. (Comparison of Mixture Methods of Embodiments 1 and 2) FIGS. 15A and 15B illustrate the relationship of the centroid positions of the pixel mixture in the first vertical line (odd-numbered line) and the second vertical line (even-numbered line) for the first field and the second field in embodiment 1. FIGS. 16A and 16B illustrate the relationship of the centroid positions of the pixel mixture in the first vertical line (odd-numbered line) and the second vertical line (even-numbered line) for the first field and the second field in embodiment 2. In FIG. 15A, centroid B1 is the centroid of pixel mixture between the pixel mixture unit areas A1 and A3 in the first vertical line of the first field. Centroid B2 is the centroid of pixel mixture between the pixel mixture unit areas A2 and A4 in the first vertical line of the first field. Centroid B3 is the centroid of pixel mixture between the pixel mixture unit areas A5 and A7 in the second vertical line of the first field. Centroid B4 is the centroid of pixel mixture between the pixel mixture unit areas A6 and A8 in the second vertical line of the first field. In FIG. 15B, centroid B′1 is the centroid of pixel mixture between the pixel mixture unit areas A′1 and A′3 in the first vertical line of the second field. Centroid B′2 is the centroid of pixel mixture between the pixel mixture unit areas A′2 and A′4 in the first vertical line of the second field. Centroid B′3 is the centroid of pixel mixture between the pixel mixture unit areas A′5 and A′7 in the second vertical line of the second field. Centroid B′4 is the centroid of pixel mixture between the pixel mixture unit areas A′6 and A′8 in the second vertical line of the second field. In FIG. 16A, centroid G1 is the centroid of pixel mixture between the pixel mixture unit areas F1 and F3 in the first vertical line of the first field. Centroid G2 is the centroid of pixel mixture between the pixel mixture unit areas F2 and F4 in the first vertical line of the first field. Centroid G3 is the centroid of pixel mixture between the pixel mixture unit areas F5 and F7 in the second vertical line of the first field. Centroid G4 is the centroid of pixel mixture between the pixel mixture unit areas F6 and F8 in the second vertical line of the first field. In FIG. 16B, centroid G′1 is the centroid of pixel mixture between the pixel mixture unit areas F′1 and F′3 in the first vertical line of the second field. Centroid G′2 is the centroid of pixel mixture between the pixel mixture unit areas F′2 and F′4 in the first vertical line of the second field. Centroid G′3 is the centroid of pixel mixture between the pixel mixture unit areas F′5 and F′7 in the second vertical line of the second field. Centroid G′4 is the centroid of pixel mixture between the pixel mixture unit areas F′6 and F′8 in the second vertical line of the second field. As shown in FIG. 15A, in the horizontal direction, centroid B1 of pixel mixture in the first vertical line (odd-numbered line) of the first field is at the median point of centroids B3 and B4 of pixel mixture in the second vertical line (even-numbered line), and centroid B4 of pixel mixture in the second vertical line (even-numbered line) of the first field is at the median point of centroids B1 and B2 of pixel mixture in the first vertical line (odd-numbered line). That is, centroids B1, B2, . . . of pixel mixture in the first vertical line and centroids B3, B4, . . . of pixel mixture in the second vertical line respectively align with equal intervals over the horizontal coordinate system. The horizontal position of the centroid of pixel mixture in the third vertical line is equal to that of the centroid of pixel mixture in the first vertical line. This also applies to the pixel mixture in the second field as shown in FIG. 15B. On the other hand, as shown in FIG. 16A, the horizontal position of centroid G1 of pixel mixture in the first vertical line (odd-numbered line) of the first field is at a position shifted from the median point of centroids G3 and G4 of pixel mixture in the second vertical line (even-numbered line), and the horizontal position of centroid G4 of pixel mixture in the second vertical line is at a position shifted from the median point of centroids G1 and G2 of pixel mixture in the first vertical line. This also applies to the pixel mixture in the second field as shown in FIG. 16B. FIG. 17A illustrates the relationship of the centroid positions of the pixel mixture in the first vertical line and the second vertical line in the example of FIGS. 15A and 15B. FIG. 17B illustrates the relationship of the centroid positions of the pixel mixture in the first vertical line and the second vertical line for the example of FIGS. 16A and 16B. As seen from FIG. 17A, in the case where the pixel mixture process of FIGS. 15A and 15B is performed, centroids B1, B2, . . . of pixel mixture in the first vertical line and centroids B3, B4, . . . of pixel mixture in the second vertical line respectively align with equal intervals over the horizontal coordinate system. As seen from FIG. 17B, in the case where the pixel mixture process of FIGS. 16A and 16B is performed, centroids G1, G2, . . . of pixel mixture in the first vertical line and centroids G3, G4, . . . of pixel mixture in the second vertical line respectively align with unequal intervals over the horizontal coordinate system. FIG. 18 is a block diagram simply showing a structure of a centroid position correction circuit. FIG. 19A illustrates an example of adding together the electric charges in a pixel mixture unit area to generate a brightness signal in the example of FIGS. 15A and 15B. FIG. 19B illustrates an example of adding together the electric charges in a pixel mixture unit area to generate a brightness signal in the example of FIGS. 16A and 16B. As shown in FIG. 18, the centroid position correction circuit includes an arithmetic operation circuit 121 which performs the operation of (1+z−1)/2 and a switching circuit 123. The centroid position correction circuit receives brightness signal SA obtained by adding together electric charge signals of adjacent pixel mixture unit areas. If brightness signal SA is a brightness signal of a reference line (odd-numbered line or even-numbered line), the switching circuit 123 is connected to the lower terminal in the drawing according to control signal LS, and a signal which has bypassed the arithmetic operation circuit 121 is output as signal Sout. If brightness signal SA is a brightness signal of a line other than the reference line (even-numbered line or odd-numbered line), the switching circuit 123 is connected to the upper terminal in the drawing according to control signal LS, and a signal which has undergone the operation of (1+z−1)/2 for centroid position correction in the arithmetic operation circuit 121 is output as signal Sout. The operation of (1+z−1)/2 is a process for interpolating a new brightness signal at the median point of the brightness signals. According to embodiment 3, in a solid state imaging element, when a pixel mixture process is performed, a pixel signal of complementary color filter format is output. Now, consider an example where pixel signals of the colors shown in the upper part of FIGS. 19A and 19B are input as pixel signals of an odd-numbered line and an even-numbered line. In the odd-numbered line, a Cy-pixel signal and a Ye-pixel signal, which are the pixel signals of adjacent pixel mixture unit areas, are mixed to generate brightness signal SA1, and a Ye-pixel signal and a Cy-pixel signal, which are the pixel signals of adjacent pixel mixture unit areas, are mixed to generate brightness signal SA2. In the even-numbered line, a Mg-pixel signal and a G-pixel signal, which are the pixel signals of adjacent pixel mixture unit areas, are mixed to generate brightness signal SA3, and a G-pixel signal and a Mg-pixel signal, which are the pixel signals of adjacent pixel mixture unit areas, are mixed to generate brightness signal SA4. In the case where the odd-numbered line is a reference line, the switching circuit 123 is controlled such that brightness signals SA1 and SA2 of the odd-numbered line bypass the arithmetic operation circuit 121 and are output as output signal Sout, and the centroid position correcting process is not performed. On the other hand, brightness signals SA3 and SA4 of the even-numbered line are input to the arithmetic operation circuit 121 and undergo the centroid position correcting process, and the corrected brightness signals are output as output signal Sout. In such a case, if the centroid positions of the mixed electric charge signals of pixel mixture unit areas in an odd-numbered line are at the median points of the centroid positions of the mixed electric charge signals of pixel mixture unit areas in an even-numbered line and vice verse over the horizontal coordinate system as shown in FIGS. 15A and 15B, brightness signals SA1 and SA2 in the odd-numbered line are at the median points of brightness signals SA3 and SA4 in the even-numbered line, and vice versa, as shown in FIG. 19A. Therefore, the centroid positions of brightness signals SA3 and SA4 in the even-numbered line are readily corrected by the operation of (1+z−1)/2 in the arithmetic operation circuit 121 to be coincident with the centroid positions of brightness signals SA1 and SA2 in the odd-numbered line. In the case where the even-numbered line is a reference line, the process opposite to that described above is performed, whereby the centroid positions are readily corrected. However, if the centroid positions of the mixed electric charge signals of pixel mixture unit areas in an odd-numbered line are not at the median points of the centroid positions of the mixed electric charge signals of pixel mixture unit areas in an even-numbered line and vice verse over the horizontal coordinate system as shown in FIGS. 16A and 16B, brightness signals SA1 and SA2 in the odd-numbered line and brightness signals SA3 and SA4 in the even-numbered line are shifted from the centroid positions of each other as shown in FIG. 19B. Thus, in order to correct the centroid positions of brightness signals SA3 and SA4 of the even-numbered line so as to be coincident with the centroid positions of brightness signals SA1 and SA2 of the odd-numbered line, a circuit structure capable of more complicated processes is required instead of using the circuit of FIG. 18. Thus, the centroid positions of pixel mixture in the odd-numbered line are aligned to be at the median points of the centroid positions of pixel mixture in the even-numbered line and vice versa as shown in FIGS. 15A and 15B. With such a structure, the process of correcting the centroid positions is simplified, and reproduction of images is quickly performed. As a result, in the reproduction of moving pictures, sharp images are obtained more readily. Thus, for example, in the case where the two pixel mixture unit areas which are mixed in the pixel mixture process of the first vertical line (odd-numbered line) are two pixel mixture unit areas which are horizontally shifted from each other by one pixel and mixed in a zigzag manner, and the two pixel mixture unit areas which are mixed in the pixel mixture process of the second vertical line (even-numbered line) are two pixel mixture unit areas which are at the same horizontal position and mixed in a non-zigzag manner, it is preferable that the two pixel mixture unit areas which are mixed in a zigzag manner are horizontally shifted by one pixel with respect to the two pixel mixture unit areas which are mixed in a non-zigzag manner. In other words, in the case where the repetition unit which constitutes the basis of arrangement of pixel mixture unit areas is formed by 4 vertically-arranged pixel mixture unit areas which are mixed on a two-by-two basis, it is preferable that the position of one pixel mixture unit area is horizontally shifted by one pixel, and another one is horizontally shifted by two pixels. In the above-described embodiments, in a moving picture imaging process with a mega-pixel solid state imaging element of a color filter arrangement where the unit area is 2 rows×2 columns, aliasing components derived from high frequency components in a low frequency range are greatly reduced even when an image including a high frequency signal in both horizontal and vertical directions of a video signal is imaged. As a result, false signals in both the brightness signal and chromaticity signal are greatly suppressed. Further, a perfect equilibrium of the pixel sampling density is achieved between the horizontal direction and the vertical direction, so that the horizontal resolution and the vertical resolution are equal. Furthermore, data from all of the pixels can be output without abandonment, and therefore, the sensitivity of the imaging element is greatly improved. Further still, even when the number of pixels of a solid state imaging element is increased, the number of output pixels which is optimal to the interlaced scanning mode can be selected by expanding the pixel mixture area for increasing the frame rate vertically and/or horizontally according to the application of the element. (Variations) The above-described embodiments have disclosed a solid state imaging device including vertical transfer stages and a horizontal transfer stage through which electric charges obtained from CCDs are transferred. However, the present invention is not limited to the above embodiments. For example, the present invention is applicable to a solid state imaging device which performs addition of electric charges obtained from MOSFETs. The solid state imaging element of the present invention does not necessarily have a color filter. The present invention is applicable to the processes of monochromic (black/white) images. Further, even in the case of using a color filter, the color filter does not need to include a color pattern of 2 rows×2 columns as a basic unit of repetition. For example, the solid state imaging element may include a multicolor filter of 5 or more colors. In the above-described embodiments, the pixel mixture unit area is formed by 5'5 pixels, but the present invention is not limited thereto. The pixel mixture unit area may be formed by a larger or smaller number pixels for the pixel mixture process. This specification does not disclose an example where embodiment 1 is applied to a solid state imaging element of a complementary color filter format. However, the filter structure of embodiment 1 may be a complementary color filter structure as embodiment 3 is realized based on embodiment 2 by replacing the filter format of embodiment 2 with a complementary color filter format. In the above-described embodiments, the number of pixels in the vertical direction (i.e., in a column) in the pixel mixture unit area, q, satisfies the relationship of q=4m+1 (m is a natural number), the number of pixels in the horizontal direction (i.e., in a row), p, satisfies the relationship of p=4n+1 (n is a natural number), and the relationship of m=n=1 is satisfied. The pixel mixture unit areas overlap one another by (q+1)/2 pixels in the first (vertical) direction and by (p+1)/2 pixels in the second (horizontal) direction to form an arrangement which has a two-dimensional repetition. However, according to the present invention, the number of pixels in the pixel mixture unit area and the amount of the overlap are not limited to the above embodiments. In one possible example of the present invention, the number of pixels in the first direction (i.e., in a column) in the pixel mixture unit area, q, satisfies the relationship of q=4m−1 (m is a natural number), the number of pixels in the second direction (i.e., in a row), p, satisfies the relationship of p=4n−1 (n is a natural number), and the pixel mixture unit areas repeatedly overlap one another alternately by (q−1)/2 pixels and (q+3)/2 pixels in the first direction and alternately by (p−1)/2 pixels and (p+3)/2 pixels in the second direction to constitute an arrangement which has a two-dimensional repetition. The pixel mixture unit area may include an even number of pixels×an even number of pixels, e.g., 6 pixels×6 pixels. Alternatively, the pixel mixture unit area may include an odd number of pixels×an even number of pixels. The above-described solid state imaging device of the present invention can be used for digital still cameras, digital video cameras, etc. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to a solid state imaging device of a digital still camera, a digital video camera, and the like. Conventionally, a solid state imaging element which converts received light to an electric signal and outputs the electric signal as a video signal has been known, and a camera which displays the video signal obtained from the solid state imaging element in the form of a static image, such as a digital still camera, or the like, has also been known. In recent years, further improvements of image quality and functions have been demanded in such a camera which uses a solid state imaging element, and the number of pixels has been rapidly increasing. For example, a solid state imaging element having about 5,000,000 pixels has about 1,920 pixels in a column (vertical direction) and about 2,560 pixels in a row (horizontal direction). The number of pixels of this element, i.e., about 5,000,000, is about 16 times that of a generally-employed NTSC solid state imaging element. The frame rate for full pixel output is about a ½ second when a conventional pixel clock of about 12 MHz is used. Thus, the video signal output from the solid state imaging element cannot be output to a display device (a liquid crystal monitor, or the like) of the camera without modifying the original frame rate. According to a driving method which has been conventionally employed in view of the above in such a solid state imaging element, the pixels from which signals are to be read are thinned along the horizontal direction while the speed of the pixel clock is increased, whereby a video signal of a moving picture is read with higher speed. For example, signals of pixels on two out of eight lines are used. Further, a technique of reducing the number of output pixels of a solid state imaging element using a pixel mixture method has been known (see Japanese Unexamined Patent Publication No. 2001-36920). However, in the above pixel thinning method, pixels are immoderately resampled in the vertical direction (¼ in the above example), and no associated spatial LPF used for this resampling in the vertical direction is not provided. Accordingly, in an image where a video signal contains high-frequency components in the vertical direction, a large amount of aliasing components deriving from the high-frequency components in the vertical direction occur in the low-frequency range. This causes not only a large number of false signals along with the generation of luminance signals and chromaticity signals but also a significant decrease in the vertical resolution with respect to the horizontal resolution due to an imbalance in pixel sampling density between the horizontal direction and the vertical direction. In addition, since signals of pixels on lines from which no data is to be read out are discarded, the substantial sensitivity decreases. In the above example, the percentage of effectively-used pixels is 25%. In the case where the above-described conventional technique is used, all of the above problems become more serious in principle as the number of pixels of a solid state imaging element increases because it is necessary to decrease the ratio of columns to be read to all of the columns of the solid state imaging element for the purpose of increasing the frame rate. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention was conceived to overcome the above problems. An objective of the present invention is to reduce the number of output pixel signals of a solid state imaging element having a large number of pixels, such as a super-megapixel imaging element, or the like, by a pixel addition method, such that moving picture imaging is realized with a super resolution solid image imaging element suitable for a system that operates based on interlaced scanning. In order to achieve the above objective, the present invention includes a solid state imaging element and performs a pixel addition process of the first and second fields wherein the electric charges of a plurality of pixels included in a plurality of pixel mixture unit areas are added together to alternately output signals of the electric charges obtained in the pixel addition process of the first and second fields as signals for interlaced scanning. Specifically, a solid state imaging device of the present invention comprises: a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction; pixel addition means for performing a first-field pixel addition process of adding together electric charges of a plurality of pixels included in the plurality of pixel mixture unit areas and a second-field pixel addition process of adding together the electric charges of the plurality of pixels included in the plurality of pixel mixture unit areas based on a combination of the pixel mixture unit areas which is different from that of the first-field pixel addition process; and output means for alternately outputting signals of the electric charges obtained in the first-field pixel addition process and second-field pixel addition process as signals for interlaced scanning. According to the solid state imaging device of the present invention, a video signal can be read with high speed without thinning pixels to be read. Therefore, signals of all the pixels can be output without abandonment and, accordingly, the sensitivity of the imaging element is greatly improved. Further, aliasing components derived from high frequency components in a low frequency range are greatly reduced. Therefore, false signals are greatly suppressed in both the brightness signal and chromaticity signal. As a result, the image quality improves. In the solid state imaging device of the present invention, preferably, the number of pixels in the first direction in each of the pixel mixture unit areas, q, satisfies the relationship of q=4m+1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, satisfies the relationship of p=4n+1 (n is a natural number); and the pixel mixture unit areas overlap one another by (q+1)/2 pixels in the first direction and by (p+1)/2 pixels in the second direction. Alternatively, the number of pixels in the first direction in each of the pixel mixture unit areas, q, may satisfy the relationship of q=4m−1 (m is a natural number), and the number of pixels in the second direction in each of the pixel mixture unit areas, p, may satisfy the relationship of p=4n−1 (n is a natural number); and the pixel mixture unit areas may repeatedly overlap one another alternately by (q−1)/2 pixels and (q+3)/2 pixels in the first direction and alternately by (p−1)/2 pixels and (p+3)/2 pixels in the second direction. Electric charges of a plurality of pixels included in one pixel mixture unit area may be added together in the first direction; and the electric charges of the pixels which are added together respectively in the plurality of pixel mixture unit areas and transferred in the first direction may be added together in the second direction. With such a structure, the process of adding the electric charges of the pixel in the first direction and the process of adding the electric charges of the pixel in the second direction are clearly separated so that a time-series process can be quickly performed. The pixel addition means may perform a plurality of line processes on two of the pixel mixture unit areas which are adjacent in the first direction wherein electric charges of the plurality of pixels included in the two pixel mixture unit areas are added together; and in at least one of the plurality of line processes, two of the pixel mixture unit areas which are shifted in the second direction by one or more pixels may be processed. With such a structure, the electric charges of pixels of different colors can readily be added together in the second direction. The centroid position of a first region formed by two of the pixel mixture unit areas which are processed in one of the line processes is on a line that extends in the first direction and passes over the median point between the centroid position of a second region formed by two of the pixel mixture unit areas which are processed in another one of the line processes and the centroid position of a third region formed by two of the pixel mixture unit areas which is processed at the same time with the second region and is placed adjacent to the second region in the second direction. With such a structure, centroid correction of a pixel signal output from the solid state imaging device is readily achieved, and the frame lag in a moving picture can be reduced. In the solid state imaging device of the present invention, preferably, the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. In this case, a color filter arrangement of the solid state imaging element may be a combination of Bayer arrangements of 2 rows×2 columns; the pixel addition means may include a first-direction transfer stage for adding together electric charges of the plurality of pixels in the first direction in each of the pixel mixture unit areas and a second-direction transfer stage for adding together the electric charges obtained by the addition in the first-direction transfer stage in the second direction; and the electric charges obtained by the addition in the second-direction transfer stage may be pixel signals for complementary color filter arrangement display. Alternatively, a color filter arrangement of the solid state imaging element may be a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. In the solid state imaging device of the present invention, preferably, the pixel addition means includes a first-direction transfer stage and a second-direction transfer stage, the first-direction transfer stage including a plurality of CCDs which transfer the electric charges of the pixels in the first direction, the second-direction transfer stage including a plurality of CCDs which transfer the electric charges transferred from the first-direction transfer stage in the second direction. With such a structure, the process of adding together the electric charges of pixels with CCDs can be realized. In this case, preferably, the second-direction transfer stage alternately includes a storage region which includes a first gate and retains an electric charge and a barrier region which includes a second gate and functions as a barrier against transfer of electric charges; and the first gate and the second gate are electrically separated to receive separate biases. With such a structure, the electric charges of the pixels in the second-direction transfer stage can be transferred not only in the forward direction but also in the reverse direction. Accordingly, the pixel addition process can be quickly performed. A method of the present invention for driving a solid state imaging device which includes a solid state imaging element including a plurality of photoelectric conversion elements arranged in a matrix, the solid state imaging element including pixels grouped into pixel mixture unit areas, each of which includes q pixels (q is a natural number equal to or greater than 2) in the first direction of the solid state imaging element and p pixels (p is a natural number equal to or greater than 2) in the second direction that crosses the first direction, comprises the steps of: (a) adding together electric charges of pixels included in each of the pixel mixture unit areas and transferring the added electric charges in the first direction; (b) adding together electric charges of pixels from a plurality of pixel mixture unit areas while the electric charges added and transferred in the first direction at step (a) are transferred in the second direction; and (c) alternately outputting signals which relates to the electric charges added together at step (b) in first and second fields as signals for interlaced scanning. According to the solid state imaging device driving method of the present invention, a video signal can be read with high speed without thinning pixels to be read. Therefore, signals of all the pixels can be output without abandonment and, accordingly, the sensitivity of the imaging element is greatly improved. Further, aliasing components derived from high frequency components in a low frequency range are greatly reduced. Therefore, false signals are greatly suppressed in both the brightness signal and chromaticity signal. As a result, the image quality improves. In the solid state imaging device driving method of the present invention, preferably, the pixel mixture unit areas overlap one another in the first and second directions to constitute an arrangement which has a two-dimensional repetition. In the solid state imaging device driving method of the present invention, preferably, at step (a), electric charges of pixels included in one pixel mixture unit area are added together in the first direction; and at step (b), the electric charges added together in the first direction at step (a) are added together in the second direction. Preferably, at step (b), a line process of adding together in the second direction electric charges of pixels of two pixel mixture unit areas which are adjacent in the first direction is performed over a plurality of stages. In the solid state imaging device driving method of the present invention, preferably, the solid state imaging element includes a color filter provided over front faces of the photoelectric conversion elements. In this case, a color filter arrangement of the solid state imaging element may be a combination of Bayer arrangements of 2 rows×2 columns; and at step (b), electric charges of pixels having different colors in each of the pixel mixture unit areas may be added together to generate a pixel signal for a complementary color filter arrangement. Alternatively, a color filter arrangement of the solid state imaging element may be a combination of four colors, cyan, yellow, green and magenta, arranged in 2 rows×2 columns. | 20050119 | 20081230 | 20050721 | 93760.0 | 1 | PRABHAKHER, PRITHAM DAVID | SOLID STATE IMAGING DEVICE AND DRIVING METHOD THEREOF | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,332 | ACCEPTED | L-ergothioneine, milk thistle, and S-adenosylmethionine for the prevention, treatment and repair of liver damage | This invention provides therapeutic compositions and combinations for the protection, treatment and repair of liver tissue. The invention relates to novel compositions and combinations comprising two or more compounds selected from the group consisting of S-adenosylmethionine, L-ergothioneine, and a substance selected from the group consisting of constituents of Milk thistle (Silybum marianum), silymarin and active components of silymarin, whether naturally, synthetically, or semi-synthetically derived, and to methods of preventing and treating liver disease and of repairing damaged liver tissue. The invention also provides a method of administering these compositions and combinations to humans or animals in need thereof. | 1. A combination comprising any two or more of the following compounds: S-adenosylmethionine, L-ergothioneine and a substance selected from the group consisting of a constituent of Milk thistle (Silybum marianum), silymarin and active components of silymarin. 2. The combination of claim 1 wherein a single dose of S-adenosylmethionine for humans or animals ranges from about 1.25 milligrams to about 10 grams. 3. The combination of claim 1 wherein a single dose of S-adenosylmethionine for humans or animals ranges from about 0.5 milligrams per kilogram to about 100 milligrams per kilogram. 4. The combination of claim 1 wherein a single dose of L-ergothioneine for humans or animals ranges from about 1.25 micrograms to about 25 grams. 5. The combination of claim 1 wherein a single dose of L-ergothioneine for humans or animals ranges from about 0.5 micrograms per kilogram to about 250 milligrams per kilogram. 6. The combination of claim 1 wherein a single dose of the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin for humans or animals ranges from about 1.25 milligrams to about 10 grams. 7. The combination of claim 1 wherein a single dose of the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin for humans or animals ranges from about 0.25 milligrams per kilogram to about 200 milligrams per kilogram. 8. The combination of claim 1 wherein the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin is standardized such that silymarin is present in the substance in an amount from about 55% to about 85% by weight of the substance. 9. The combination of claim 8 wherein silymarin is present in the substance in an amount from about 67.5% to about 72.5% by weight of the substance. 10. The combination of claim 1 wherein the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin is standardized such that Silybin A and Silybin B are present in the substance in a combined amount from about 20% to about 35% by weight of the substance. 11. The combination of claim 10 wherein the Silybin A and Silybin B are present in the substance in a combined amount of about 28% by weight of the substance. 12. The combination of claim 1 wherein the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin is standardized such that Isosilybin A and Isosilybin B are present in the substance in a combined amount from about 20% to about 35% by weight of the substance. 13. The combination of any of claims 2-12 wherein the combination comprises a composition. 14. A method of improving or maintaining the health of liver tissue of a human or other animal or of normalizing or improving the function of the liver of a human or other animal, comprising: administering to a human or other animal a therapeutically or prophylactically effective amount of any two or more of S-adenosylmethionine, L-ergothioneine, and a substance selected from the group consisting of a constituent of Milk thistle (Silybum marianum), silymarin and active components of silymarin. 15. The method of claim 14 wherein a daily dose of S-adenosylmethionine for humans or animals ranges from about 5 milligrams to about 10 grams. 16. The method of claim 14 wherein a daily dose of S-adenosylmethionine for humans or animals ranges from about 2 milligrams per kilogram to about 100 milligrams per kilogram. 17. The method of claim 14 wherein a daily dose of L-ergothioneine for humans or animals ranges from about 5 micrograms to about 25 grams. 18. The method of claim 14 wherein a daily dose of L-ergothioneine for humans or animals ranges from about 2 micrograms per kilogram to about 250 milligrams per kilogram. 19. The method of claim 14 wherein a daily dose of the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin for humans or animals ranges from about 5 milligrams to about 10 grams. 20. The method of claim 14 wherein a daily dose of the substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin for humans or animals ranges from about 1 milligram per kilogram to about 200 milligrams per kilogram. | CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a continuation-in-part application of U.S. patent application Ser. No. 09/256,352, filed Feb. 24, 1999, the disclosure of which is hereby incorporated by reference herein in its entirety. That application claimed priority to provisional application: “L-ERGOTHIONEINE, MILK THISTLE, AND S-ADENOSYLMETHIONINE FOR LIVER FAILURE,” U.S. Ser. No. 60/076,347, filed Feb. 27, 1998, the disclosure of which is hereby incorporated by reference herein in its entirety. FIELD OF THE INVENTION The present invention relates to compositions and combinations for the protection, treatment and repair of liver tissues in humans and animals. BACKGROUND OF THE INVENTION The liver is an extremely important organ. As the major metabolic organ of the body, the liver plays some role in almost every biochemical process, including the deamination of amino acids and the formation of urea, the regulation of blood sugar through the formation of glycogen, the production of plasma proteins, the production and secretion of bile, phagocytosis of particulate matter from the splanchnic (intestinal) circulation, and the detoxification and elimination of both endogenous and exogenous toxins. The many functions of the liver depend on its intimate association with circulating blood. Each liver cell is exposed on at least one face to a blood sinusoid which contains oxygenated arterial blood mixed with venous blood from the splanchnic circulation. This profuse blood supply is necessary for the liver to function. The blood from the sinusoids supplies the hepatocytes with oxygen and nutrients. The hepatocytes use the nutrients both for their own metabolic needs and for the synthesis of the liver's many essential products. Abnormalities in the blood or vasculature can have immediate and severe effects on the liver. For example, liver cells are exposed to high concentrations of any toxic compounds that are ingested orally, such as ethyl alcohol. Even when the ingested compound is not itself toxic, intermediate derivatives produced during hepatic metabolism of the compound may damage the hepatocytes. This phenomenon occurs, for example, in carbon tetrachloride poisoning. Since the blood moves slowly through hepatic sinusoids, liver cells are also quite vulnerable to blood-borne infectious agents such as viruses and bacteria. Furthermore, derangements in hepatic blood pressure can damage liver tissue. Right-sided cardiac failure increases hepatic blood pressure and can lead to pressure necrosis (hepatocellular death) and fibrosis. Left-sided cardiac failure can reduce hepatic perfusion and lead to hepatocellular anoxia and death. Liver damage from any source may result in liver regeneration, necrosis (cell death), degeneration, inflammation, fibrosis, or mixtures of these processes, depending on the type and extent of injury and its location within the liver. The liver has great functional reserves, but with progressive injury, disruption of liver function can have life-threatening consequences. Cirrhosis, which is a type of end-stage liver disease, is one of the top ten causes of death in the Western world. Despite the significance and potential severity of liver disease, therapeutic approaches are limited. Treatment is generally symptomatic, e.g., the use of diuretics to combat tissue edema caused by low levels of plasma proteins. Many types of liver disease are the result of viruses (e.g., hepatitis A, B, C, D and E, to name a few), and effective antiviral therapies are rare and commonly cause potentially severe side effects. Other liver diseases are the result of previous toxic exposure (such as alcoholic cirrhosis and exposure to toxic plants, or environmental pollutants) which may be difficult to control. In still other cases, liver disease is the result of poorly understood interplay of various factors, including genetic factors, environmental conditions, and immune system activity (autoimmune hepatitis). These cases are, in a word, idiopathic, and as such are difficult to treat except symptomatically. In short, due in part to the complexity of liver disease, therapies do not currently exist that address its causes. Nor does there currently exist a therapy that supports normal liver function and helps heal damaged liver tissue. Currently available therapies either focus only on the secondary symptoms of liver disease or have significant side effects, as is the case with antiviral drugs. There is a need for a therapeutic composition that will support liver structure, function and healing, with few or no side effects. SUMMARY OF THE INVENTION The present invention provides compositions and combinations for the protection, treatment and repair of liver tissue in humans and animals. Additionally, the present invention provides such compositions and combinations that also produce a low level of side effects. The present invention also provides a method of using the novel compositions and combinations of the present invention to protect, treat or repair liver tissue in humans or animals in need thereof. The present invention provides novel compositions, combinations and methods for protecting, treating and repairing liver tissue. The compositions and combinations of the invention include two or more of the following compounds: S-adenosylmethionine, L-ergothioneine and a substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin, whether naturally, synthetically, or semi-synthetically derived. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is the molecular structure of S-adenosylmethionine. FIG. 2 diagrams the major metabolic pathways of S-adenosylmethionine in the body. FIG. 3 diagrams the effects of ethanol in the hepatocyte. FIG. 4 is the molecular structure of L-ergothioneine. FIG. 5 shows the effect of ergothioneine and other compounds on lipid peroxide formation in mouse liver homogenate. FIG. 6 is a drawing of the herb Milk thistle (Silybum marianun). FIG. 7 is the molecular structures of silybin and other compounds from Milk thistle. DETAILED DESCRIPTION OF THE INVENTION In accordance with the teachings of the present invention, disclosed herein are compositions, combinations and methods for the protection, treatment and repair of liver tissue. The invention relates to novel compositions and combinations comprising two or more compounds selected from the group consisting of S-adenosylmethionine, L-ergothioneine, and a substance selected from the group consisting of constituents of Milk thistle (Silybum marianum), silymarin and active components of silymarin, whether naturally, synthetically, or semi-synthetically derived, and to methods of preventing and treating liver disease and of repairing damaged liver tissue. S-adenosylmethionine (“SAMe”) (FIG. 1) is a significant physiologic compound that is present throughout body tissue and that takes part in a number of biologic reactions as a methyl group donor or an enzymatic activator during the synthesis and metabolism of hormones, neurotransmitters, nucleic acids, phospholipids, and proteins. It is naturally formed in the body from ATP and methionine. SAMe is an extremely important reactant in many biochemical reactions including transmethylation, transsulfation, and synthesis of amines (FIG. 2). Stramentinoli, G., Pharmacologic Aspects of S-Adenosylmethionine, American Journal of Medicine 83 (5A), 1987, pp. 35-42. In higher organisms, SAMe plays a significant role in transmethylation processes in more than 40 anabolic or catabolic reactions involving the transfer of the methyl group of SAMe to substrates such as nucleic acids, proteins and lipids, among others. The release of the methyl group from SAMe is also the start of a “transsulfuration” pathway that produces all endogenous sulfur compounds. After donating its methyl group, SAMe is converted into S-adenosylhomocysteine, which in turn is hydrolyzed to adenosine and homocysteine. The amino acid cysteine may then be produced from the homocysteine. Cysteine may exert a reducing effect by itself or as an active part of glutathione, which is a main cell antioxidant. Id. SAMe additionally has anti-oxidant effects via its derivatives (e.g., methylthioadenosine), which prevent oxidative damage to ells. Glutathione itself is a product of SAMe via the transmethylation and transsulfation pathways. SAMe and its products, including glutathione, are of great importance in the prevention of liver damage. The changes produced by ethanol (EtOH) in the liver provide examples of injuries that can occur in the liver on the cellular level (FIG. 3), and help explain the mechanism of action by which SAMe counteracts these injuries. EtOH absorbed in the blood stream is metabolized in the liver by the enzyme alcohol dehydrogenase. This reaction releases excess nicotinamide-adenine-dinucleotide (NADH) which in turn shunts substrates (carbohydrates, lipids, and proteins) in the liver away from normal catabolic processes and towards lipid biosynthesis. As lipids accumulate in the liver cells in the form of large droplets, organelles are physically displaced and crowded, and this phenomenon decreases the cells' ability to function. Secondly, alcohol induces the P 450 system of cytochromes, and the microsomal ethanol oxidizing system (“MEOS”) within liver cells, leading to augmented transformation of various compounds in the body (including, for example, chemicals from tobacco smoke) into toxic metabolites, and producing free radicals. Because alcohol consumption decreases glutathione pools, damage already produced by these free radicals is exacerbated. Alcohol and its metabolites (e.g., acetaldehyde) also interact with phospholipids and therefore have direct effects on hepatocellular membranes, decreasing their fluidity and affecting the function of organelles such as mitochondria and endoplasmic reticulum. Finally, acetaldehyde alters hepatocellular proteins, including the sodium/potassium pump, decreasing the ability of these proteins to function. The sodium/potassium pump is a membrane-bound protein that is responsible for maintaining the balance of sodium and potassium across the cell membrane of every cell in the body. Because many cell functions depend on the electrochemical gradient that results from this distribution of sodium and potassium, the sodium/potassium pump is essential to enable cells to perform. Liver cells are no exception. The alterations in proteins that alcohol and its metabolites induce also have the effect of making these proteins more ‘foreign’ and thus more likely to induce autoimmune reactions. In short, alcohol damages the liver in a myriad of ways. FIG. 3; Lieber, C., Biochemical factors in alcoholic liver disease, Seminars in Liver Disease, 13 (2), 1993, pp. 136-53. SAMe has a variety of beneficial effects in cells and protects hepatocytes from these injurious influences in a number of different ways. For example, SAMe has been shown to decrease lipid accumulation in rats chronically intoxicated with ethanol. This effect is not completely understood, but is partially explained by SAMe's ability to inhibit alcohol dehydrogenase. This single function of SAMe in itself prevents not only lipid accumulation but also much of the additional damage acetaldehyde causes to cellular membranes and proteins. Pascale, R., et al., Inhibition by ethanol of rat liver plasma membrane (Na+K+)ATPase: protective effect of SAMe, L-methionine, and N-acetylcysteine, Toxicology and Applied Pharmacology, 97, 1989, pp. 216-29. Furthermore, because SAMe catalyses the transformation of phosphatidylethanolamine to phosphatidylcholine, it supports the normal fluidity of cell membranes, thereby supporting the structure and function of organelles including the plasma membrane, mitochondria and endoplasmic reticulum. This supportive effect avoids many of alcohol's damaging secondary effects. Bevi B., et al., Protection of rat fetal hepatocytes membranes from ethanol mediated cell injury and growth impairment, Hepatology 16, 1992, p. 109A. SAMe also protects liver cells indirectly via its antioxidant products cysteine and glutathione, which help prevent damage by the excessive free radicals produced during alcohol intoxication. Pascale R., et al., The role of SAMe in the regulation of glutathione pool and acetaldehyde production in acute ethanol intoxication, Research Communications in Substances of Abuse, Vol. 5, No. 4, 1984, pp. 321-24. Laboratory animal studies and in vitro experiments have verified these effects of SAMe on the inner, lipid layer of the plasma membrane. Champ, P. and Harvey, R., Biochemistry, 2nd ed., Lippincott, Philadelphia, 1994, pp. 266-7; Stramentinoli, G., Pharmacologic aspects of SAMe, American Journal of Medicine, Vol. 83 (5A) 1987, p. 35; Baldessarini, F., Neuropharmacology of S-Adenosyl Methionine, American Journal of Medicine 83 (5A), 1987, p. 95; Carney, M., Neuropharmacology of S-Adenosyl Methionine, Clinical Neuropharmacology 9 (3), 1986, p. 235; Janicak, P., S-Adenosylmethionine in Depression, Alabama Journal of Medical Sciences 25 (3), 1988, p. 306. SAMe has been used to treat various disorders. In certain forms of liver disease, SAMe acts as an anticholestatic agent. Adachi, Y., et al., The Effects of S-adenosylmethionine on Intrahepatic Cholestasis, Japan Arch. Inter. Med., 33 (6), 1986, pp. 185-92. One mechanism by which SAMe exerts this effect is via its ability to maximize membrane fluidity, which is a crucial factor in the secretion of bile acids from hepatocytes. Id. Another mechanism is via the transsulfation pathway and the production of sulfates and taurine, which are important in mobilization of bile acids. Frezza, M., The use of SAMe in the treatment of cholestatic disorders, Drug Investigation, 4 (Suppl. 4), 1992, pp. 101-08. Low levels of SAMe are believed to play a role in increasing the risk of certain cancers. Feo F., et al., Early Stimulation of Polyamine Biosynthesis During Promotion by Phenobarbital of Diethylnitrosamine-induced Rat Liver Carcinogenesis. The Effects of Variations of the S-adenosyl-L-methionine Cellular Pool, Carcinogenesis, 6 (12), 1985, pp. 1713-20. The administration of SAMe has also been associated with a fall in the amount of early reversible nodules and the prevention of the development of late pre-neoplastic lesions and hepatocellular carcinomas. Garcea, R., et al., Variations of Ornithine Decarboxylase Activity and S-adenosyl-L-methionine and 5′-methylthioadenosine Contents During the Development of Diethylnitrosamine-induced Liver Hyperplastic Nodules and Hepatocellular Carcinoma, Carcinogenesis, 8 (5), 1987, pp. 653-58. SAMe is avaliable in many different salt forms as would be known by a person of ordinary skill in the art, any of which, or any combination of which, would be useful in the invention. SAMe and its salt forms may be natural, semisynthetic, bioengineered, synthetic or extracted, any of which, or any combination of which, would be useful in the invention. L-ergothioneine (FIG. 4) is a naturally occurring antioxidant that is very stable in the body. It is synthesized in fungi and microorganisms and present in both plants and animals. Animals are unable to synthesize L-ergothioneine and must obtain it from dietary sources. It is readily absorbed and is active in most mammalian tissues, concentrating especially in the liver, where it prevents certain types of free-radical-induced damage to cell membranes and organelles. For example, exogenous L-ergothioneine has been shown to prevent lipid peroxidation by toxic compounds in the liver tissue of rats. Akanmu, D., et al., The antioxidant action of ergothioneine, Arch. of Biochemistry and Biophysics, 288 (1), 1991, pp. 10-16; Kawano, H., et al., Studies on Ergothioneine: Inhibitory effect on lipid peroxide formation in mouse liver, Chem. Pharm. Bull., 31 (5), 1983, pp. 1662-87. In study comparing the inhibition of lipid peroxide (“LPO”) formation by various compounds in mouse liver, L-ergothioneine both inhibited LPO formation and enhanced the decomposition of existing LPO (FIG. 5). Id. L-ergothioneine additionally has been shown to inhibit the damaging effects caused by the oxidation of iron-containing compounds, such as hemoglobin and myoglobin. These molecules are important in the body as carriers of oxygen, but because they contain divalent iron, they can interact with hydrogen peroxide via the Fenton reaction to produce the even more damaging hydroxyl radical. This is the mechanism by which damage occurs during so-called reperfusion injury. Because L-ergothioneine acts as a reducing agent of the ferryl-myoglobin molecule, it can protect tissues from reperfusion injury. Hanlon, D., Interaction of ergothioneine with metal ions and metalloenzymes, J. Med. Chem., 14 (11), 1971, pp. 1084-87. Although L-ergothioneine does not directly scavenge superoxide anion or hydrogen peroxide, it contributes to the control of these free radicals by participating in the activation of superoxide dismutase and glutathione peroxidase. Its protective effects on cell membranes and other organelles are of benefit in acute and chronic toxicity as well as in infectious diseases, because common pathogenic biomechanisms are active in both of these processes. Ergothionine in any form would be useful in the invention, including natural, semisynthetic, bioengineered, synthetic, extracted and combinations thereof and including any other active forms, such as racemic mixtures (D & L forms). Because ergothioneine is available in nature, it is expected that daily microgram amounts will be effective as an antioxidant. Other antioxidants, such as selenium, are known to be effective as antioxidants at these very low levels. Milk thistle (Silybum marianum) (FIG. 6), which is also commonly known as Marian thistle, St. Mary's thistle, and Our Lady's thistle, is a native to the Mediterranean region, but has been naturalized in California and the eastern United States. This tall herb with prickly variegated leaves and milky sap has been used as a folk remedy for liver and biliary complaints for many years and recent research has supported such medicinal use. Foster, S., A Field Guide to Medicinal Plants, Houghton Mifflin Co, Boston, 1990, p. 198. Research over the past 20 years has documented that the plant contains a compound referred to as silymarin, which actually consists of various forms of hepatoprotectant flavonolignans. The principal components are silybin (which is also called silybinin); silychristin; and silydianin (which is also called silymonin); the 3-deoxy-derivatives of silychristin and silydianin; as well as isosilychristin; isosilybin (which is also known as isosilybinin) and its 3-deoxy derivative silandrin; the 3-deoxy compounds silyhermin A and B; 2,3 dehydrosilybin; and the trimers, quatramers and pentamers of silybin (which collectively are referred to as silybinomers). Other flavanolignans may be included as well. Isomers of silybin (or silybinin) are silybin A and B (or silybinin A and B). For purposes of this application, the term, “silybin” shall be used, but shall include silybinin. The structure of some of these are illustrated in: (FIG. 7). Tyler, V., The Honest Herbal, Haworth Press, Inc., New York, 1993, pp. 209-10; Wichtl, M. (Grainger Bisset, N, trans.), Herbal Drugs and Phytopharmaceuticals, CRC Press, Boca Raton, 1994, pp. 121, 124, 125. These hepatoprotectant flavonolignans are referred to in this application as “active components of silymarin.” The fruits (often erroneously referred to as the “seeds”) of the plant, for example, contain approximately 3% flavonolignans on average. Laboratory trials in animals have shown that silymarins protect liver tissue against a variety of toxins including those of the deadly amanita mushrooms and carbon tetrachloride. Prophylactic effects were especially pronounced. Milk thistle is usually available as an extract that contains silymarin, but it is envisioned that any form or formulation of Milk thistle, e.g., extract, precipitate, or powdered form, which contains either silymarin or one or more active components of silymarin, would function in the present invention. In a preferred embodiment of the invention, the Milk thistle component or components may be “standardized,” i.e., formulated so that a certain percentage or amount of a specific substance or of specific substances is or are present. As an example, the Milk thistle component of the invention (i.e. silymarin and the principal active components of silymarin, such as silybin, silydianin and silychristin) could be an extract. In that case, the extract can be standardized with respect to the percentage by weight of any or all of the silymarin constituents, particularly the silybin fractions present in the extract. For example, silymarin may be present in the extract in an amount from about 55% to about 85% by weight of the extract. In a more preferred embodiment, silymarin may be standardized so that it is present in an amount from about 67.5% to about 72.5% by weight of the extract. In another preferred embodiment the extract can be standardized to the amount of Silybinin A and Silybinin B, which may be present in a combined amount from about 20% to about 35% by weight, and most preferably about 28% by weight of the extract. In a still further preferred embodiment, Isosilybin A (also known as Isosilybinin A) and Isosilybin B (also known as Isosilybinin B) may be present in a combined amount from about 20% to about 35% by weight of the extract, as measured by HPLC (high pressure liquid chromatography). It may be possible to standardize the extract with respect to other flavonolignan fractions or isomers, such as dehydrosilybin, silydianin and silycristin, as well as their 3-deoxy derivatives. Each of these preferred embodiments may be present alone or in any combination. Recently, it has been shown that oral absorption of silymarin can be increased by combining the silimarin with phosphatidylcholine and this combination may also be used in the present invention. Silymarin and the active components of silymarin have several mechanisms of action, including stimulation of nucleolar polymerase A. This stimulation in turn increases ribosomal activity leading to increased synthesis of cellular proteins, and an increased rate of hepatocellular repair. Conti, M., et al., Protective activity ofsilipide on liver damage in rodents, Japan J. Pharmacol., 60, 1992, pp. 315-21. Other protective mechanisms involve changes in the molecular structure of the hepatocellular membrane, which reduce binding and entry of toxins into the cell, and an antioxidant effect. Parish, R. & Doering, P., Treatment of Amanita mushroom poisoning: a review, Vet. Hum. Toxocol., 28 (4) 1986, pp. 318-22. It is expected that elements of the combinations of the present invention will work synergistically together because they have different, but complementary, mechanisms of action. Because liver diseases involve a complex interplay of numerous factors, the exact nature of which may remain obscure to the diagnosing clinician, there is a need for a composition that will address numerous mechanisms of liver damage. Treating the causative agent may not be—and in liver disease rarely is—possible. Addressing and preventing hepatic injuries on the cellular level therefore frequently will be the best treatment possible and almost as beneficial. The present invention combines antiinflammatory, anti-lipid, anti-necrotic, regenerating, and anti-fibrotic effects. All three ingredients that may be included in compositions of the present invention, S-adenosylmethionine, L-ergothioneine and a compound selected from the group consisting of Milk thistle, silymarin and active components of silymarin, have strong anti-inflammatory effects because of their antioxidant properties. Because different antioxidants have their primary effect on different free radicals, (for example, superoxide dismutase scavenges primarily superoxide anion), and because several types of free radicals are implicated in liver damage, supplying just one antioxidant would only address one subset of liver-damaging free radicals. It would also have a direct protective effect on protecting the hepatic cells when cells are stimulated by SAMe and or Silymarin to increase protein synthesis as this action of increased cell metabolism generates free radicals which can be neutralized by ergothionine. Combining two of the three compounds will produce a beneficial effect in a number of liver diseases, and combining all three compounds will help treat or prevent an extremely broad range of such diseases. Thus, the compositions and combinations of the present invention will improve and maintain the health of liver tissue and normalize and improve the function of the liver in humans and animals. The combination will also allow beneficial effects to be achieved using lower doses than would otherwise be necessary. The use of lowered doses is both economically advantageous and reduces the risk of any potential side effects. Although the present ingredients are remarkably free of side effects, no compound is completely innocuous and giving the lowest effective dose is always sound medical policy. The compositions and combinations of the present invention can be administered by a variety of routes including, but not limited to: orally, parentally, transdermally, sublingually, intravenously, intramuscularly, rectally and subcutaneously. Preferred daily doses for cach of the compounds are as follows. As would be apparent to a person of ordinary skill in the art, these dose ranges are approximations: SAMe Total dose range: about 5 mg—about 10 grams Preferred small animal dose range: about 5 mg—about 1600 mg Preferred human dose range: about 20 mg—about 5000 mg Preferred large animal dose range: about 100 mg—about 10 grams Alternatively, the daily per kilogram dose range of SAMe for all species is: about 2 mg/kg—about 100 mg/kg L-ergothioneine Total dose range: about 5 μg—about 25 grams Preferred small animal dose range: about 5 μg—about 5 grams Preferred human dose range: about 25 μg—about 10 grams Preferred large animal dose range: about 100 μg—about 25 grams Alternatively, the daily per kilogram dose range of L-ergothionine for all species is: about 2 μg/kg—about 250 mg/kg Constituent of Milk thistle or silymarin, or active components of silymarin, (i.e., silybin, isosilybin, etc.) Total dose range: about 5 mg—about 10 grams Preferred small animal dose range: about 5 mg—about 1000 mg Preferred human dose range: about 100 mg—about 5 grams Preferred large animal dose range: about 250 mg—about 10 grams Alternatively, the daily per kilogram dose range of a consituent of Milk thistle, silymarin, or active components of silymarin for all species is: about 1 mg/kg—about 200 mg/kg The daily doses recited above for all compounds may be given in a single dose or divided doses, to be administered, for example, twice-a-day, three-times a day or four-times-a-day. Therefore, the range for a single dose of the components of the invention is as follows: SAMe Total single dose range: about 1.25 mg—about 10 grams Preferred small animal single dose range: about 1.25 mg—about 1600 mg Preferred human single dose range: about 5 mg—about 5000 mg Preferred large animal single dose range: about 25 mg—about 10 grams Alternatively, the per kilogram single dose range of SAMe for all species is: about 0.5 mg/kg—about 100 mg/kg L-ergothioneine Total single dose range: about 1.25 μg—about 25 grams Preferred small animal single dose range: about 1.25 μg—about 5 grams Preferred human single dose range: about 6.25 μg—about 10 grams Preferred large animal single dose range: about 25 μg—about 25 grams Alternatively, the per kilogram single dose range for all species is: about 0.5 μg/kg—about 250 mg/kg Constituent of Milk thistle (or silymarin, or active components of silymarin, ie., silybin, isosilybin, etc.) Total single dose range: about 1.25 mg—about 10 grams Preferred small animal single dose range: about 1.25 mg—about 1000 mg Preferred human single dose range: about 25 mg—about 5 grams Preferred large animal single dose range: about 62.5 mg—about 10 grams Alternatively, the per kilogram single dose range of a constituent of Milk thistle, silymarin, or active components of silymarin for all species is: about 0.25 mg/kg—about 200 mg/kg Moreover, the dose may be administered in various combinations in which the components may be present in a single dosage form or in more than one dosage form. For example, the combinations of the present invention may be administered in a single daily dosage form in which all components are present, e.g., in a single capsule or tablet. The doses may also be administered in combinations of more than one dosage form in which each dosage form contains at least one component or in which two or more components are combined into a single dosage form. For example, a combination of SAMe and ergothioneine may be administered as a pill, capsule or tablet of SAMe and a separate pill, tablet or capsule of ergothioneine. A combination of ergothioneine, SAMe and silymarin may include each component in a separate dosage form, or two of the components in one dosage form, such as combined in the same capsule and the other component in a separate dosage form, or, as explained above, all three of the components in the same (i.e., a single) dosage form. These combinations may be provided in kits or blister packs, in which more than one dosage form of the various components are provided in the same package or container, for co-administration to a human or animal. For example, a tablet of SAMe and a capsule of silymarin can be placed in the same blister pack for co-administration. These combinations may be provided, for example, in kits, blister packs, packets or bottles shrink-wrapped together in which more than one dosage form of the various components are provided in the same dispensing unit for coadministration to a human or animal. Having discussed the composition of the present invention, it will be more clearly perceived and better understood from the following specific examples which are intended to provide examples of the preferred embodiments and do not limit the present invention. Moreover, as stated above, the preferred components described in these examples may be replaced by or supplemented with the any of the components of the compositions of the invention described above. EXAMPLE 1 A 10-year-old female spayed domestic cat is diagnosed with feline idiopathic hepatic lipidosis (fatty liver). This disease is characterized by the accumulation of triglycerides within the cytoplasm of liver cells. The cells become so swollen with lipids that they cease to function, and many die (hepatic necrosis). The cellular swelling also inhibits blood flow in hepatic sinusoids, compounding the damage with poor perfusion. Symptoms of the disease include loss of appetite, vomiting, depression and CNS signs (hepatic encephalopathy). Since the cause of this disease is unknown, it is currently treated symptomatically. Even with aggressive treatment, 40 to 50% of affected animals succumb. In this case, in addition to symptomatic treatment (tube feeding, fluids, pharmacologic control of vomiting), the patient is given daily a mixture of 100 mg SAMe, 100 mg silymarin, and 100 mg of L-ergothionine until appetite returns. The SAMe and silymarin support repair of damaged hepatocytes and their function, the production of enzymes and other proteins. The L-ergothioneine prevents reperfusion injury. The net result is that the cat recovers, and the rate of recovery is increased so that the cat spends fewer days hospitalized. EXAMPLE 2 A farmer in Lancaster County, Pennsylvania, reports that one of his cows has died in convulsions and that several sheep and a pig in the same pasture are also sick. Poisoning by cocklebur plants (Xanthium strumarium) is diagnosed. In this condition, a toxin produced by the plant causes fatty change, swelling, and death in liver cells. Animals that survive the initial illness may develop chronic liver disease. Currently, the only method of treatment is removal of the plant from the diet. In this case, the pigs and sheep are removed from the pasture and administered daily SAMe (5 mg/kg), silymarin (40 mg/kg), and L-ergothioneine (100 mg per animal) for one to two weeks. The SAMe helps maintain cellular membranes and the Na/K/ATPase pump, which are the cellular organelles most likely to be damaged by the toxin. The silymarin stimulates synthesis of replacement proteins and the L-ergothioneine prevents reperfusion injury. EXAMPLE 3 A 58-year-old man has osteoarthritis. To control the pain in his joints, he takes large amounts of the drug acetaminophen. Like many other drugs, acetaminophen can cause hepatic damage by decreasing glutathione levels. This patient wishes to continue to take acetaminophen, because nonsteroidal anti-inflammatory drugs cause unacceptable gastrointestinal irritation. In this case, the patient continues to take acetaminophen, but also takes SAMe 200 mg, and L-ergothioneine 100 mg daily as long as he continues to take acetaminophen. The SAMe increases hepatic glutathione levels, and the L-ergothioneine ensures maximum effect of the available glutathione via glutathione peroxidase activation. The net result is that liver structure and function are supported in the face of an ongoing potentially hepatotoxic exposure. Many modifications may be made without departing from the basic spirit of the present invention. Accordingly, it will be appreciated by those skilled in the art that within the scope of the appended claims, the invention may be practiced other than has been specifically described herein. Hence, the attached claims are intended to cover the invention embodied in the claims and substantial equivalents thereto. | <SOH> BACKGROUND OF THE INVENTION <EOH>The liver is an extremely important organ. As the major metabolic organ of the body, the liver plays some role in almost every biochemical process, including the deamination of amino acids and the formation of urea, the regulation of blood sugar through the formation of glycogen, the production of plasma proteins, the production and secretion of bile, phagocytosis of particulate matter from the splanchnic (intestinal) circulation, and the detoxification and elimination of both endogenous and exogenous toxins. The many functions of the liver depend on its intimate association with circulating blood. Each liver cell is exposed on at least one face to a blood sinusoid which contains oxygenated arterial blood mixed with venous blood from the splanchnic circulation. This profuse blood supply is necessary for the liver to function. The blood from the sinusoids supplies the hepatocytes with oxygen and nutrients. The hepatocytes use the nutrients both for their own metabolic needs and for the synthesis of the liver's many essential products. Abnormalities in the blood or vasculature can have immediate and severe effects on the liver. For example, liver cells are exposed to high concentrations of any toxic compounds that are ingested orally, such as ethyl alcohol. Even when the ingested compound is not itself toxic, intermediate derivatives produced during hepatic metabolism of the compound may damage the hepatocytes. This phenomenon occurs, for example, in carbon tetrachloride poisoning. Since the blood moves slowly through hepatic sinusoids, liver cells are also quite vulnerable to blood-borne infectious agents such as viruses and bacteria. Furthermore, derangements in hepatic blood pressure can damage liver tissue. Right-sided cardiac failure increases hepatic blood pressure and can lead to pressure necrosis (hepatocellular death) and fibrosis. Left-sided cardiac failure can reduce hepatic perfusion and lead to hepatocellular anoxia and death. Liver damage from any source may result in liver regeneration, necrosis (cell death), degeneration, inflammation, fibrosis, or mixtures of these processes, depending on the type and extent of injury and its location within the liver. The liver has great functional reserves, but with progressive injury, disruption of liver function can have life-threatening consequences. Cirrhosis, which is a type of end-stage liver disease, is one of the top ten causes of death in the Western world. Despite the significance and potential severity of liver disease, therapeutic approaches are limited. Treatment is generally symptomatic, e.g., the use of diuretics to combat tissue edema caused by low levels of plasma proteins. Many types of liver disease are the result of viruses (e.g., hepatitis A, B, C, D and E, to name a few), and effective antiviral therapies are rare and commonly cause potentially severe side effects. Other liver diseases are the result of previous toxic exposure (such as alcoholic cirrhosis and exposure to toxic plants, or environmental pollutants) which may be difficult to control. In still other cases, liver disease is the result of poorly understood interplay of various factors, including genetic factors, environmental conditions, and immune system activity (autoimmune hepatitis). These cases are, in a word, idiopathic, and as such are difficult to treat except symptomatically. In short, due in part to the complexity of liver disease, therapies do not currently exist that address its causes. Nor does there currently exist a therapy that supports normal liver function and helps heal damaged liver tissue. Currently available therapies either focus only on the secondary symptoms of liver disease or have significant side effects, as is the case with antiviral drugs. There is a need for a therapeutic composition that will support liver structure, function and healing, with few or no side effects. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention provides compositions and combinations for the protection, treatment and repair of liver tissue in humans and animals. Additionally, the present invention provides such compositions and combinations that also produce a low level of side effects. The present invention also provides a method of using the novel compositions and combinations of the present invention to protect, treat or repair liver tissue in humans or animals in need thereof. The present invention provides novel compositions, combinations and methods for protecting, treating and repairing liver tissue. The compositions and combinations of the invention include two or more of the following compounds: S-adenosylmethionine, L-ergothioneine and a substance selected from the group consisting of a constituent of Milk thistle, silymarin and active components of silymarin, whether naturally, synthetically, or semi-synthetically derived. | 20050119 | 20090721 | 20050616 | 92440.0 | 2 | MCINTOSH III, TRAVISS C | L-ERGOTHIONEINE, MILK THISTLE, AND S-ADENOSYLMETHIONINE FOR THE PREVENTION, TREATMENT AND REPAIR OF LIVER DAMAGE | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,037,430 | ACCEPTED | Aqueous compositions containing metronidazole | An aqueous solution of metronidazole in which the concentration of metronidazole is higher than 0.75%. The solution contains a combination of solubility-enhancing agents, one of which is a cyclodextrin such as beta-cyclodextrin and the second is niacin or niacinamide. Methods of manufacture and therapeutic use of the solution are disclosed. | 1. A method for making an aqueous composition containing a dissolved concentration of metronidazole greater than 0.75% w/w comprising combining metronidazole, beta-cyclodextrin (BCD), and niacin or niacinamide in an aqueous fluid. 2. The method of claim 1 wherein the aqueous composition is physically stable when stored for one week at 5° C. 3. The method of claim 1 wherein the metronidazole is added to the aqueous fluid after the BCD and the niacin or niacinamide are dissolved in the aqueous fluid. 4. The method of claim 1 which further comprises, after the combination of metronidazole, BCD, and the niacin or niacinamide, adding a gelling agent. 5. The method of claim 1 wherein niacinamide but not niacin is combined. 6. The method of claim 1 wherein niacin but not niacinamide is combined. 7. An aqueous composition that is made by the method of claim 1. 8. An aqueous composition that is made by the method of claim 4. 9. An aqueous composition that is made by the method of claim 5. 10. An aqueous composition that is made by the method of claim 6. 11. A method for the treatment of a dermatologic or mucosal disorder comprising topically applying an effective amount of an aqueous composition of metronidazole having a concentration higher than 0.75% w/w to the site of the disorder and permitting the metronidazole to treat the disorder, wherein the composition comprises beta-cyclodextrin (BCD) and niacin or niacinamide, and wherein the composition is physically stable when stored for one week at 5° C. 12. The method of claim 11 wherein the concentration of metronidazole is about 1% or higher. 13. The method of claim 12 wherein the application is once daily. 14. The method of claim 11 wherein the disorder is rosacea. 15. The method of claim 11 wherein the composition comprises niacin and is substantially free of niacinamide. 16. The method of claim 11 wherein the composition comprises niacinamide and is substantially free of niacin. 17. The method of claim 11 wherein the aqueous composition is a gel. 18. A kit for the topical treatment of dermatologic or mucosal disorders comprising a container and an aqueous composition of metronidazole, beta-cyclodextrin, and niacin or niacinamide within said container, wherein the concentration of metronidazole in said composition is higher than 0.75% w/w, and wherein the aqueous composition is physically stable when stored for one week at 5° C. 19. The kit of claim 18 wherein the concentration of niacin or niacinamide is about 1.0% w/w or higher. 20. The kit of claim 19 wherein the concentration of beta-cyclodextrin is 0.5% w/w or higher. 21. The kit of claim 18 wherein the concentration of metronidazole is about 1% w/w or higher. 22. The kit of claim 18 wherein the aqueous composition is a gel. 23. The kit of claim 18 wherein the composition contains niacinamide and is substantially free of niacin. 24. The kit of claim 18 wherein the composition contains niacin and is substantially free of niacinamide. 25. An aqueous solution that is physically stable for at least one week at 5° C. comprising metronidazole, a first solubility enhancing agent which is betacyclodextrin, and a second solubility enhancing agent which is niacin or niacinamide, wherein in the solution, the concentration of metronidazole is about 1.0% w/w or higher. 26. The aqueous solution of claim 25 wherein the concentration of betacyclodextrin is 0.5% w/w or higher. 27. The aqueous solution of claim 25 wherein the concentration of niacinamide or niacin is about 0.5% w/w or higher. 28. The aqueous solution of claim 25 wherein the solubility enhancing agent is niacinamide. 29. The aqueous solution of claim 25 wherein the solubility enhancing agent is niacin. 30. The aqueous solution of claim 25 which comprises niacinamide and does not comprise niacin. 31. The aqueous solution of claim 25 wherein the concentration of niacinamide or niacin is about 1.0% w/w or higher. 32. The aqueous solution of claim 31 which comprises niacinamide and does not comprise niacin. 33. The aqueous solution of claim 25 which is a gel. 34. A method for increasing the solubility of metronidazole in aqueous fluid comprising combining metronidazole, betacyclodextrin, and niacinamide or niacin in an aqueous fluid. 35. The method of claim 34 wherein the concentration of betacyclodextrin in the fluid is 0.5% w/w or more. 36. The method of claim 34 wherein the concentration of niacinamide or niacin in the fluid is about 1.0% or higher. 37. The method of claim 34 wherein the aqueous fluid is a gel. 38. The method of claim 34 which comprises combining niacinamide in the fluid. 39. The method of claim 34 which comprises combining niacin in the fluid. 40. The method of claim 34 wherein the solubility of metronidazole is increased to 0.75% w/w or more. 41. The method of claim 40 wherein the solubility of metronidazole is increased to about 1.0% w/w or more. 42. The method of claim 34 wherein the betacyclodextrin and the niacin or niacinamide are dissolved in the aqueous fluid before the metronidazole is combined in the fluid. 43. The method of claim 34 wherein a gelling agent is added to the fluid after the metronidazole, betacyclodextrin, and the niacin or niacinamide are combined in the fluid. 44. A method for increasing the enhancing effect of betacyclodextrin on the solubility of metronidazole in aqueous fluid comprising combining niacin or niacinamide with the betacyclodextrin in the aqueous fluid. 45. The method of claim 44 wherein the concentration of betacyclodextrin in the fluid is 0.5% or more. 46. The method of claim 44 wherein the concentration of niacin or niacinamide is about 1.0% w/w or more. 47. The method of claim 44 wherein the niacin or niacinamide is combined in the fluid with the betacyclodextrin and then metronidazole is added to the fluid. 48. The method of claim 44 wherein niacin is combined with the betacyclodextrin in the aqueous fluid. 49. The method of claim 44 wherein niacinamide is combined with the betacyclodextrin in the aqueous fluid. 50. An aqueous solution comprising metronidazole at a concentration of 0.75% w/w or higher, betacyclodextrin, and niacinamide, wherein the solution is free of crystal or precipitate formation when stored for one week at 5° C. 51. The aqueous solution of claim 50 wherein the concentration of metronidazole is about 1% w/w or higher. 52. The aqueous solution of claim 50 which is an aqueous gel solution. 53. A method for obtaining an aqueous composition containing betacyclodextrin at a concentration greater than 0.5% w/w, comprising combining in an aqueous fluid betacyclodextrin and niacinamide or niacin wherein the amount of the niacinamide or niacin combined in the aqueous fluid is sufficient to provide a dissolved concentration of betacyclodextrin greater than 0.5% w/w at a temperature of 5° C. 54. The method of claim 53 wherein the aqueous composition obtained is a solution that is physically stable for one week at 5° C. 55. The method of claim 53 wherein the aqueous composition is an aqueous gel composition. 56. The method of claim 53 wherein the concentration of the niacinamide or niacin in the aqueous composition is 0.5% w/w or higher. 57. The method of claim 53 wherein the concentration of the niacinamide or niacin in the aqueous composition is 1.0% w/w or higher. | This is a continuation application claiming priority from pending U.S. patent application Ser. No. 10/033,835. FIELD OF THE INVENTION The invention pertains to the field of topically applied medications for treatment of skin and mucosal disorders. In particular, the invention pertains to aqueous compositions containing metronidazole as the active ingredient. BACKGROUND OF THE INVENTION Metronidazole, 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole, has long been known as an effective drug to treat a variety of disorders, and is especially well known for the treatment of various protozoal diseases. As a topical therapy, metronidazole has also been shown to be useful in treating various skin disorders, including acne rosacea, bacterial ulcers, and perioral dermatitis. See, Borgman, U.S. Pat. No. 4,837,378. Metronidazole has been found to have an anti-inflammatory activity when used topically to treat dermatologic disorders. See, Czernielewski, et al., U.S. Pat. No. 5,849,776. Metronidazole may also be used as an intravaginal therapeutic agent for the treatment of bacterial vaginosis. See, Borgman, U.S. Pat. No. 5,536,743. Compositions containing metronidazole for treatment of dermatologic disorders are available in cream, lotion and gel forms. One commercially available metronidazole cream product, NORITATE™ (Dermik Laboratories, Inc., Collegeville, Pa. 19426 USA) contains 1% metronidazole in which the insoluble drug is suspended in the opaque cream. A commercially available metronidazole gel product, METROGEL® (Galderma Laboratories, Inc. Fort Worth, Tex., 76133 USA), contains 0.75% metronidazole which is solubilized to produce a clear gel. For the treatment of many dermatologic and mucosal disorders, it is often preferable to use a solubilized water-based formulation, such as a gel, rather than a cream, lotion or an ointment. Creams, lotions (typically oil in water emulsions) and ointments (typically petroleum jelly based compositions) are often comedogenic, acnegenic, or not cosmetically appealing to patients. Solubilized topical products are generally more bioavailable than products in which the active ingredient is insoluble. The oil-based cream and ointment metronidazole formulations have an advantage over presently available gel-based formulations in that oil-based formulations may contain a concentration of metronidazole of 1%. Aqueous-based gel compositions are limited to a concentration of metronidazole of 0.75% because of the poor solubility of metronidazole in water. Cyclodextrins have been shown to enhance the solubility of various drugs in aqueous solutions. An amphiphilic or lipophilic drug, such as metronidazole, is partially or completely enclosed within this cage structure, thereby increasing the solubility of the drug in aqueous media. Cyclodextrins have certain disadvantages, however, including expense, limitations of cyclodextrin solubility, incompatibility in certain vehicles, and potential for local and systemic toxicity. Several authors have described the use of beta-cyclodextrin (BCD) in combination with metronidazole. Kata and Antal, Acta Pharmaceutica Hungarica, 54:116-122 (1984), disclose a marked increase in the rate of dissolution of metronidazole when dissolved in a solution containing BCD at 37° C. The stability of the BCD/metronidazole solutions is not addressed. Major problems with the use of BCD to solubilize drugs such as metronidazole is that BCD has a relatively low solubility in water and is a relatively inefficient solubilizer, particularly for lipophilic or amphiphilic drugs such as metronidazole. Additionally, cyclodextrins, such as BCD and its derivatives, are expensive and the drug formulations containing BCD as a solubilizing agent likewise become expensive. A need exists for a way to increase the solubility of drugs which requires a reduced concentration of BCD. Solubility enhancing agents other than cyclodextrins have been described. Yie W. Chien, Journal of Parenteral Science and Technology, 38(1):32-36 (January 1984), discloses that niacinamide is a solubility enhancing agent that can increase the water solubility of MTZ. Chien further discloses that the water soluble vitamins ascorbic acid, and pyridoxine are solubility enhancing agents for aqueous solutions. Chien discloses that the solubility of metronidazole in water increases linearly with relation to the concentration of these water soluble vitamins in the solution. The Chien article is incorporated herein by reference. The prior art does not address the combination of cyclodextrins, such as BCD, with other solubility enhancing agents, such as niacinamide or other water soluble vitamins. SUMMARY OF THE INVENTION It has been surprisingly discovered that the combination of a cyclodextrin and a second solubility enhancing agent, such as niacinamide or niacin, has a synergistic effect on the aqueous solubility of amphiphilic or lipophilic chemical compounds such as metronidazole. The second solubility enhancing agent may be other than niacinamide or niacin. The synergistic effect provided by the combination of cyclodextrin and the second solubility enhancing agent permits the use of lower concentrations of cyclodextrins than would be necessary to obtain a desired level of solubility of the chemical compound in the absence of the second solubility enhancing agent. Because cyclodextrins are expensive, has limited aqueous solubility, and is not entirely free of toxicity, the invention provides an important way to greatly reduce costs in the formulation and preparation of pharmaceutical preparations, as well as to increase the solubilizing capability of cyclodextrins such as BCD, and to obtain desired concentrations of pharmacologic compounds while minimizing the amount of cyclodextrins used. As used herein, the term “solubility enhancing agent” or “solubility enhancer” means a chemical compound that, when present in solution in a solvent, increases the solubility of a second chemical compound, such as an active ingredient, in the solvent, but which chemical compound is not itself a solvent for the second chemical compound. All concentrations referred to in this specification are % w/w, unless indicated otherwise. The invention is described below with reference to a particular cyclodextrin, BCD, and a particular chemical compound, metronidazole. It is conceived, however, that the invention is applicable to other cyclodextrins, both crystalline and non-crystalline, including alpha and gamma cyclodextrins, and crystalline and non-crystalline derivatives thereof, and other amphiphilic and lipophilic chemical compounds besides metronidazole. Physically stable aqueous solutions of higher than 0.75% metronidazole (MTZ) may be obtained by combining in the solution a first solubility enhancing agent which is a cyclodextrin, such as beta-cyclodextrin (BCD), and a second solubility enhancing agent, such as niacinamide or niacin. The combination of the cyclodextrin and the second solubility enhancing agent provides a synergistic effect in increasing the solubility of MTZ in water. These discoveries permit the production of aqueous MTZ solutions, including solutions that are gels, at levels of 1% MTZ or higher. At such levels, MTZ may be effectively used as a topical medicament. In one embodiment, the invention is an aqueous solution having a concentration of MTZ higher than 0.75% w/w, preferably about 1% or higher. The aqueous solution contains a cyclodextrin, such as BCD, as a first solubility enhancing agent and a second solubility enhancing agent, such as niacin or niacinamide. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the solution is substantially free of aqueous solubility-enhancing agents other than a cyclodextrin and the second solubility enhancing agent. Preferably, the solution is an aqueous gel. In another embodiment, the invention is a method for the manufacture of an aqueous solution of MTZ having a concentration greater than 0.75%, preferably about 1.0% or higher. The method includes combining MTZ and two solubility enhancing agents, one of which is a cyclodextrin such as BCD, in a water based solution wherein the concentration of the final aqueous solution of MTZ is higher than 0.75%. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, an excess of the second solubility enhancing agent may be used. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, a gelling agent is further combined in the solution, preferably after addition of the MTZ and the solubility-enhancing agents. In another embodiment, the invention is a method for the treatment of a dermatologic or mucosal disorder. The method includes topically applying to affected areas an aqueous solution of MTZ and a cyclodextrin, such as BCD, and a second solubility enhancing agent, such as niacin or niacinamide., which solution has a concentration of MTZ higher than 0.75%, preferably about 1.0% or higher. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the aqueous solution is a gel. In another embodiment, the invention is a kit for the treatment of a dermatologic or mucosal disorder. The kit of the invention includes a container that contains an aqueous solution of MTZ and which aqueous solution contains a first solubility enhancing agent which is a cyclodextrin, such as BCD, and a second solubility enhancing agent such as niacin or niacinamide. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the aqueous solution is a gel. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a diagrammatic representation of a preferred embodiment of the kit of the invention. DETAILED DESCRIPTION OF THE INVENTION It has been unexpectedly discovered that stable aqueous solutions of metronidazole (MTZ) of greater than 0.75% w/w, and even about 1.0% or higher, are able to be obtained by using a combination of solubility-enhancing agents, wherein one of the solubility enhancing agents is a cyclodextrin, such as BCD, and the second solubility enhancing agent is other than a cyclodextrin. Examples of suitable second enhancing agents include niacin and niacinamide. As used in this specification, the term “stable” refers to physical, rather than chemical, stability. In accordance with the invention, the metronidazole solutions of the invention are physically stable, that is substantially no crystal or precipitate from solution, when stored at refrigerated temperatures of 5° C. for at least 7 days. The physically stable aqueous solutions of metronidazole at concentrations greater than 0.75% are obtained without the substantial presence of water-miscible organic solvents, such as ethyl alcohol or propylene glycol, which may be irritating to intact or damaged skin or mucosal surfaces. The elimination of these organic solvents provides a therapeutic solution that has decreased potential for irritation and makes the solutions especially good for treating topical dermatologic conditions, such as rosacea, that may be worsened by irritating chemicals present in a therapeutic formulation. However, if desired, such organic solvents may be included in the solution, up to a concentration of about 10%. In a most preferred embodiment, the aqueous solutions are substantially free of organic solvents for MTZ. The stable aqueous MTZ solutions of the invention have a concentration of MTZ greater than 0.75% w/w. Preferably, the concentration of MTZ in the solution of the invention is about 1.0%. In accordance with the invention, the concentration of MTZ in aqueous solution may be even higher, such as 1.25%, 1.5%, 2.0%, or 2.5%, or more. At a level of 1% or higher of MTZ, the aqueous solution may be effectively used therapeutically as a topical formulation. The solution is preferably in the form of a gel. Therefore, the aqueous MTZ solution preferably contains a gelling agent. Any gelling agent that is water-dispersible and forms an aqueous gel of substantially uniform consistency is suitable for use in the solution of the invention so long as the gelling agent does not substantially interfere with the water solubility of MTZ or with the therapeutic efficacy of the solution. “Substantially interfere” means that the inclusion of the gelling agent decreases the solubility of MTZ to 0.75% w/w or less in aqueous solution. A preferred gelling agent is hydroxyethylcellulose (NATROSOL™, Hercules Inc., Wilmington, Del., USA). Examples of other suitable gelling agents include carboxyvinyl polymers, such as CARBOPOL® 934, 940, and 941 (Noveon, Inc., Akron, Ohio, USA). The level of the cyclodextrin in the solution may be varied depending upon the desired dissolved concentration of MTZ. In general, it is preferable to use as low a concentration of cyclodextrin as possible to obtain the desired concentration of MTZ because cyclodextrins are expensive, of limited aqueous solubility, not entirely free of toxicity, and the presence of cyclodextrin may be irritating to certain intact and diseased skin and mucosal surfaces. In accordance with the invention, the concentration of cyclodextrin in aqueous solution may be between 0.1% and 20%, or higher. Preferably, the concentration of cyclodextrin in the solution is no more than about 5% w/w. In the case of beta-cyclodextrin, the concentration in aqueous solution is limited by its solubility in water. An aqueous solution, such as a gel, of beta-cyclodextrin is saturated at a concentration of about 0.5% at 5° C. (refrigerator temperature). The solutions, especially in gel formulation, are non-tacky, fast-drying, and cosmetically elegant. The solutions, including the gel formulations, are physically stable at 5° C. (refrigerator temperature) or room temperature conditions for at least 7 days. No crystal formation or precipitation is observed after one week at 5° C. It is preferred that the aqueous solution of the invention be substantially free of pharmacologically active compounds other than MTZ having a water-solubility which is increased by the presence of cyclodextrins. These other compounds may act as competitors for the sequestration sites within the cyclodextrin cage structure and reduce the MTZ solubility enhancement by the cyclodextrin. Multiple solutes that are increased in solubility by cyclodextrins may be utilized in the solutions so long as the level of cyclodextrin and the second solubility enhancer in the solution is sufficiently high to result in the desired dissolved concentration of MTZ, even in the presence of the competitor solute. In a preferred embodiment of the invention, the amount of cyclodextrin in the solution is at a level below that which enhances the solubilization of MTZ to the level desired, and a second solubility enhancer, such as niacinamide or niacin, is included in the solution at a level that permits the desired concentration of MTZ in aqueous solution to be attained. For example, if a stable 1% MTZ aqueous solution is desired, 0.1% to 1.0% BCD may be used and an amount of niacinamide or niacin may be combined in the solution to bring the solubility of MTZ to 1%. The amount of niacinamide to be combined in the solution is less than that which, without the presence of BCD in the solution, can enhance the solubility of MTZ sufficiently to obtain a 1% solution of MTZ, or whatever level of MTZ is desired. In accordance with this embodiment of the invention for a 1% aqueous solution of MTZ, the concentration of BCD % w/w in the solution is preferably at a level of 1.0% or less and the concentration of niacinamide or niacin equal to or more than that of BCD. The aqueous solutions, including the aqueous gels, of the invention may be made in any way that results in a stable MTZ concentration of greater than 0.75%, preferably of 1.0% or higher. Preferably, the solubility enhancers and the MTZ are combined in water, or a water-based solution, before the addition of a gelling agent, or at least before gelling of the solution occurs. Preferably, the solubility enhancers are dissolved in water before addition of the MTZ. In a preferred method of manufacture of the aqueous solution of the invention, an aqueous solution of BCD and niacinamide or niacin is prepared, wherein the levels of BCD and niacinamide or niacin are as described above. Metronidazole is then added to the solution. The amount of metronidazole added to the solution may be an amount calculated to provide the desired concentration of MTZ or it may be an excess amount of MTZ. The solution is preferably stirred or agitated at an elevated temperature and then permitted to cool to room or refrigerator temperature. A gelling agent, if desired, is preferably added at any time after the addition of MTZ to the solution. Most preferably, the gelling agent is added to the solution after the agitation of the solution, during the cooling of the solution, or following cooling of the solution. The solutions of the invention, including gels, may be used for the topical treatment of dermatologic or mucosal disorders that are responsive to therapy with metronidazole. In accordance with the method of treatment of the invention, a stable aqueous solution containing metronidazole at a concentration higher than 0.75% w/w, preferably about 1% or higher, is topically applied to skin or mucosal surfaces in need of such therapy. The applied solution preferably contains a cyclodextrin like BCD, as described above, in combination with niacin or niacinamide, as described above. The therapeutic method of the invention may be used to treat any disorder that is responsive, or potentially responsive, to metronidazole therapy. Examples of disorders that are suitably treated in accordance with the invention include inflammatory lesions on the skin, oral mucosa, or vaginal mucosa, diabetic foot ulcers, and certain infectious diseases that may be treated topically. In a preferred embodiment, the method of the invention is used to treat rosacea. At concentrations of about 1% or higher, the application of the metronidazole solution is preferably only once daily. The solution is applied on a daily basis, one or more times per day, for a time sufficient to produce an amelioration or a cure of the disorder. In certain chronic disorders, the solution may be applied one or more times daily for a prolonged period to prevent worsening of the disorder. In another embodiment of the invention, a kit (FIG. 1) is provided for the topical treatment of skin or mucosal disorders. The kit contains ajar 101 or other container suitable for holding an aqueous metronidazole solution as described herein, and instructions (not illustrated) for applying the solution topically to affected areas of the skin or mucosal surface. Preferably, the metronidazole solution has a concentration of metronidazole of about 1% or higher and the instructions call for applying the metronidazole solution to affected areas once daily. The jar 101 is preferably packaged within a box 102, upon which additional information, such as instructions, may be written. The following non-limiting examples provide a further description of the invention. EXAMPLE 1 All solutions in the following examples contain the components listed as the generic formula or gel vehicle shown in Table 1. TABLE 1 COMPONENT % w/w Methylparaben 0.15 Propylparaben 0.05 Phenoxethanol 0.7 Edetate sodium 0.05 Hydroxyethyl cellulose (HEC) 1.25 Beta-cyclodextrin (BCD) As shown in Tables 2 to 6 Niacinamide or Niacin As shown in Tables 2 to 6 Purified Water QS 100.00 Different solutions according to Table 1 were made with varying concentrations of beta-cyclodextrin (BCD). The solutions of BCD were maintained at 5° C. monitored weekly for two weeks for signs of crystal or precipitate formation. The results are shown in Table 2. The data show that the saturated BCD solubility in the aqueous solutions at 5° C. is about 0.5%. TABLE 2 BCD % w/w Results after storage at 5° C. 0.5 Clear after 2 weeks 0.6 Crystals formed after 2 weeks 0.7 Crystals at one week 0.9 Crystals at one week 1.0 Crystals at one week 1.2 Crystals at one week 1.4 Crystals at one week 1.5 Crystals at one week EXAMPLE 2 Different concentrations of metronidazole were prepared with the gel vehicle of Example 1 containing 0.5% BCD. The metronidazole (MTZ)/BCD solutions were maintained at 5° C. for one week. The results are shown in Table 3. TABLE 3 BCD % w/w MTZ % w/w Result at 5° C., 1 week 0.5 0.9 Crystals formed 0.5 0.8 Clear 0.5 0.7 Clear From this study, the stable solubility of metronidazole in the gel vehicle containing 0.5% BCD at 5° C. was determined to be about 0.8% w/w. EXAMPLE 3 A similar study using various concentrations of niacinamide showed that the concentration of niacinamide required to obtain a stable aqueous gel solution of 1.0% metronidazole is about 3%. Various gel solutions of Table 1 were prepared with a concentration of 1.0% metronidazole and containing either 0.5% or 1.0% BCD and differing concentrations of niacinamide. The gels were maintained at 5° C. for one week to observe for precipitate or crystal formation. The results are shown in Table 4. TABLE 4 BCD Niacinamide Metronidazole Results at 5° C., % w/w % w/w % w/w 1 week 0.5 0.5 1.0 Crystals formed 0.5 1.0 1.0 Clear 0.5 2.0 1.0 Clear 1.0 0.5 1.0 Precipitate formed 1.0 1.0 1.0 Clear 1.0 2.0 1.0 Clear The results in Table 4 show that concentrations of BCD and niacinamide as low as 0.5% and 1.0%, respectively, may be used together to obtain a physically stable aqueous gel solution of 1.0% metronidazole. EXAMPLE 4 Various gel solutions of Table 1 were prepared with a concentration of 1.0% metronidazole and various concentrations of niacin. The pH was adjusted to 5.0+/−0.15 with trolamine. The solutions were maintained at 5° C. for one week to observe evidence of precipitation or crystal formation. The results are shown in Table 5. TABLE 5 Niacin % w/w MTZ % w/w Results, 5° C., 1 week 2.0 1.0 Clear 1.8 1.0 Clear 1.5 1.0 Clear 1.2 1.0 Clear 1.0 1.0 Clear 0.75 1.0 Clear 0.5 1.0 Clear/Crystals formed* 0.25 1.0 Crystals formed 0.25 1.0 Crystals formed 0.15 1.0 Crystals formed 0.10 1.0 Crystals formed *seven out of eight samples showed crystal formation The results in Table 5 show that the minimum concentration of niacin required to obtain a stable 1.0% metronidazole gel solution is greater than 0.5% and preferably about 0.75%. EXAMPLE 5 Various solutions according to Table 1 with 1% metronidazole, 0.5% niacin, pH adjusted to 5.0+/−0.15 and varying concentrations of BCD. The solutions were maintained at 5° C. for one week to observe for crystal or precipitate formation. The results are shown in Table 6. TABLE 6 BCD % w/w Niacin % w/w MTZ % w/w Results, 5° C., 1 week 0.2 0.5 1.0 Crystals formed 0.3 0.5 1.0 Crystals formed 0.5 0.5 1.0 Clear As shown in Table 6, using a combination of 0.5% niacin and 0.5% BCD, a stable 1.0% aqueous gel solution of metronidazole was produced. The above data in Examples 1 to 5 show that BCD at its maximum soluble aqueous concentration raises the stable solubility of MTZ in aqueous solution, such as a gel, at 5° C. by 0.1%, that is from 0.7% to 0.8%. A 3% concentration of niacinamide is needed to increase MTZ aqueous solubility by 0.3% to 1%. Thus, niacinamide at about 3% raises the physically stable solubility of MTZ in aqueous gel by an amount that is about 3 times the increase provided by the maximum soluble concentration of BCD. When BCD and niacinamide are both utilized in the solution, the two compounds act synergistically to increase the solubility of MTZ in water. The data in Examples 1 to 5 show that when BCD is added to an aqueous solution at an amount expected to yield an increase of 0.1% and niacinamide is added at a level that is one third the amount of niacinamide that is able to raise the solubility of MTZ by 0.3%, this combination results in a solubility of MTZ that is 0.3% above its unaided solubility. Similar results were obtained using a 0.5% concentration of niacin, a concentration which is below that which produces a stable 1% solution of metronidazole. When this concentration of niacin was combined with 0.5% BCD, a concentration that provides only a 0.1% increase in MTZ aqueous solubility to 0.8%, the solubility of MTZ was synergistically increased to 1% at a pH of about 5. Various modifications of the above described invention will be evident to those skilled in the art. For example, more than one cyclodextrin may be used, such as beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin. Similarly, the second solubility enhancing agent may be a multiplicity of solubility enhancing agents, such as both niacin and niacinamide. It is intended that such modifications are included within the scope of the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Metronidazole, 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole, has long been known as an effective drug to treat a variety of disorders, and is especially well known for the treatment of various protozoal diseases. As a topical therapy, metronidazole has also been shown to be useful in treating various skin disorders, including acne rosacea, bacterial ulcers, and perioral dermatitis. See, Borgman, U.S. Pat. No. 4,837,378. Metronidazole has been found to have an anti-inflammatory activity when used topically to treat dermatologic disorders. See, Czernielewski, et al., U.S. Pat. No. 5,849,776. Metronidazole may also be used as an intravaginal therapeutic agent for the treatment of bacterial vaginosis. See, Borgman, U.S. Pat. No. 5,536,743. Compositions containing metronidazole for treatment of dermatologic disorders are available in cream, lotion and gel forms. One commercially available metronidazole cream product, NORITATE™ (Dermik Laboratories, Inc., Collegeville, Pa. 19426 USA) contains 1% metronidazole in which the insoluble drug is suspended in the opaque cream. A commercially available metronidazole gel product, METROGEL® (Galderma Laboratories, Inc. Fort Worth, Tex., 76133 USA), contains 0.75% metronidazole which is solubilized to produce a clear gel. For the treatment of many dermatologic and mucosal disorders, it is often preferable to use a solubilized water-based formulation, such as a gel, rather than a cream, lotion or an ointment. Creams, lotions (typically oil in water emulsions) and ointments (typically petroleum jelly based compositions) are often comedogenic, acnegenic, or not cosmetically appealing to patients. Solubilized topical products are generally more bioavailable than products in which the active ingredient is insoluble. The oil-based cream and ointment metronidazole formulations have an advantage over presently available gel-based formulations in that oil-based formulations may contain a concentration of metronidazole of 1%. Aqueous-based gel compositions are limited to a concentration of metronidazole of 0.75% because of the poor solubility of metronidazole in water. Cyclodextrins have been shown to enhance the solubility of various drugs in aqueous solutions. An amphiphilic or lipophilic drug, such as metronidazole, is partially or completely enclosed within this cage structure, thereby increasing the solubility of the drug in aqueous media. Cyclodextrins have certain disadvantages, however, including expense, limitations of cyclodextrin solubility, incompatibility in certain vehicles, and potential for local and systemic toxicity. Several authors have described the use of beta-cyclodextrin (BCD) in combination with metronidazole. Kata and Antal, Acta Pharmaceutica Hungarica, 54:116-122 (1984), disclose a marked increase in the rate of dissolution of metronidazole when dissolved in a solution containing BCD at 37° C. The stability of the BCD/metronidazole solutions is not addressed. Major problems with the use of BCD to solubilize drugs such as metronidazole is that BCD has a relatively low solubility in water and is a relatively inefficient solubilizer, particularly for lipophilic or amphiphilic drugs such as metronidazole. Additionally, cyclodextrins, such as BCD and its derivatives, are expensive and the drug formulations containing BCD as a solubilizing agent likewise become expensive. A need exists for a way to increase the solubility of drugs which requires a reduced concentration of BCD. Solubility enhancing agents other than cyclodextrins have been described. Yie W. Chien, Journal of Parenteral Science and Technology, 38(1):32-36 (January 1984), discloses that niacinamide is a solubility enhancing agent that can increase the water solubility of MTZ. Chien further discloses that the water soluble vitamins ascorbic acid, and pyridoxine are solubility enhancing agents for aqueous solutions. Chien discloses that the solubility of metronidazole in water increases linearly with relation to the concentration of these water soluble vitamins in the solution. The Chien article is incorporated herein by reference. The prior art does not address the combination of cyclodextrins, such as BCD, with other solubility enhancing agents, such as niacinamide or other water soluble vitamins. | <SOH> SUMMARY OF THE INVENTION <EOH>It has been surprisingly discovered that the combination of a cyclodextrin and a second solubility enhancing agent, such as niacinamide or niacin, has a synergistic effect on the aqueous solubility of amphiphilic or lipophilic chemical compounds such as metronidazole. The second solubility enhancing agent may be other than niacinamide or niacin. The synergistic effect provided by the combination of cyclodextrin and the second solubility enhancing agent permits the use of lower concentrations of cyclodextrins than would be necessary to obtain a desired level of solubility of the chemical compound in the absence of the second solubility enhancing agent. Because cyclodextrins are expensive, has limited aqueous solubility, and is not entirely free of toxicity, the invention provides an important way to greatly reduce costs in the formulation and preparation of pharmaceutical preparations, as well as to increase the solubilizing capability of cyclodextrins such as BCD, and to obtain desired concentrations of pharmacologic compounds while minimizing the amount of cyclodextrins used. As used herein, the term “solubility enhancing agent” or “solubility enhancer” means a chemical compound that, when present in solution in a solvent, increases the solubility of a second chemical compound, such as an active ingredient, in the solvent, but which chemical compound is not itself a solvent for the second chemical compound. All concentrations referred to in this specification are % w/w, unless indicated otherwise. The invention is described below with reference to a particular cyclodextrin, BCD, and a particular chemical compound, metronidazole. It is conceived, however, that the invention is applicable to other cyclodextrins, both crystalline and non-crystalline, including alpha and gamma cyclodextrins, and crystalline and non-crystalline derivatives thereof, and other amphiphilic and lipophilic chemical compounds besides metronidazole. Physically stable aqueous solutions of higher than 0.75% metronidazole (MTZ) may be obtained by combining in the solution a first solubility enhancing agent which is a cyclodextrin, such as beta-cyclodextrin (BCD), and a second solubility enhancing agent, such as niacinamide or niacin. The combination of the cyclodextrin and the second solubility enhancing agent provides a synergistic effect in increasing the solubility of MTZ in water. These discoveries permit the production of aqueous MTZ solutions, including solutions that are gels, at levels of 1% MTZ or higher. At such levels, MTZ may be effectively used as a topical medicament. In one embodiment, the invention is an aqueous solution having a concentration of MTZ higher than 0.75% w/w, preferably about 1% or higher. The aqueous solution contains a cyclodextrin, such as BCD, as a first solubility enhancing agent and a second solubility enhancing agent, such as niacin or niacinamide. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the solution is substantially free of aqueous solubility-enhancing agents other than a cyclodextrin and the second solubility enhancing agent. Preferably, the solution is an aqueous gel. In another embodiment, the invention is a method for the manufacture of an aqueous solution of MTZ having a concentration greater than 0.75%, preferably about 1.0% or higher. The method includes combining MTZ and two solubility enhancing agents, one of which is a cyclodextrin such as BCD, in a water based solution wherein the concentration of the final aqueous solution of MTZ is higher than 0.75%. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, an excess of the second solubility enhancing agent may be used. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, a gelling agent is further combined in the solution, preferably after addition of the MTZ and the solubility-enhancing agents. In another embodiment, the invention is a method for the treatment of a dermatologic or mucosal disorder. The method includes topically applying to affected areas an aqueous solution of MTZ and a cyclodextrin, such as BCD, and a second solubility enhancing agent, such as niacin or niacinamide., which solution has a concentration of MTZ higher than 0.75%, preferably about 1.0% or higher. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the aqueous solution is a gel. In another embodiment, the invention is a kit for the treatment of a dermatologic or mucosal disorder. The kit of the invention includes a container that contains an aqueous solution of MTZ and which aqueous solution contains a first solubility enhancing agent which is a cyclodextrin, such as BCD, and a second solubility enhancing agent such as niacin or niacinamide. Preferably, the level of each of the cyclodextrin and the second solubility enhancing agent is less than that which, in the absence of the other solubility enhancing agent, would provide for a dissolved concentration of the MTZ to the level of that present in the aqueous solution. If desired, however, the solution may contain an excess of the second solubility enhancing agent. Most preferably, the enhanced solubility of MTZ in the combination solution is higher than the sum of the enhanced solubilities of MTZ in two solutions, each of which contains a single solubility enhancer at the concentration present in the combination solution. Preferably, the aqueous solution is a gel. | 20050118 | 20080325 | 20050609 | 96618.0 | 3 | MAIER, LEIGH C | AQUEOUS COMPOSITIONS CONTAINING METRONIDAZOLE | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,037,497 | ACCEPTED | OMNIDIRECTIONAL TILT AND VIBRATION SENSOR | An omnidirectional tilt and vibration sensor contains a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and multiple electrically conductive weights. The first electrically conductive element has a first diameter on a proximate portion of the first electrically conductive element and a second diameter on a distal portion of the first electrically conductive element, where the second diameter is smaller than the first diameter. The second electrically conductive element is similar to the first. In addition, the electrically insulative element is connected to the first electrically conductive element and the second electrically conductive element. The electrically conductive weights are located within a cavity of the sensor, wherein the cavity is defined by surface of the first electrically conductive element, the electrically insulative element, and the second electrically conductive element. | 1. A sensor, comprising: a first electrically conductive element having a first diameter on a proximate portion of the first electrically conductive element and a second diameter on a distal portion of the first electrically conductive element, where the second diameter is smaller than the first diameter; a second electrically conductive element having a first diameter on a proximate portion of the second electrically conductive element and a second diameter on a distal portion of the second electrically conductive element, where the second diameter is smaller than the first diameter; an electrically insulative element connected to the first electrically conductive element and the second electrically conductive element, where the distal portion of the first electrically conductive element fits within a proximate end of the electrically insulative element, where the distal portion of the second electrically conductive element fits within a distal end of the electrically insulative element, and where the proximate portion of the first electrically conductive element and the proximate portion of the second electrically conductive element are located external to the electrically insulative element; and multiple electrically conductive weights located within a cavity of the sensor, wherein the cavity is defined by an interior surface of the first electrically conductive element, the electrically insulative element, and an interior surface of the second electrically conductive element. 2. The sensor of claim 1, wherein the sensor is in a closed state if a conductive path exists from the first electrically conductive element, to the multiple electrically conductive weights, to the second electrically conductive element, and wherein the sensor is in an open state if there is no conductive path from the first electrically conductive element, to the multiple electrically conductive weights, to the second electrically conductive element. 3. The sensor of claim 1, wherein the first electrically conductive element is hermetically sealed to the electrically insulative element and the second electrically conductive element is hermetically sealed to the electrically insulative element. 4. The sensor of claim 1, wherein the first electrically conductive element further comprises a flat end surface located on a side opposite the distal portion of the first electrically conductive element, and wherein the second electrically conductive element further comprises a flat end surface located on a side opposite the distal portion of the second electrically conductive element. 5. The sensor of claim 4, wherein the flat end surface of the first electrically conductive element contains a first nub for providing electrical contact of the first electrically conductive element to a first terminal, and wherein the flat end surface of the second electrically conductive element contains a second nub for providing electrical contact of the second electrically conductive element to a second terminal. 6. The sensor of claim 1, wherein the first electrically conductive element and the second electrically conductive element are equal in dimension. 7. The sensor of claim 1, wherein the electrically insulative element is fabricated from a material selected from the group consisting of plastic and glass. 8. The sensor of claim 1, wherein the distal portion of the first electrically conductive element further comprises: a first top surface; a first outer surface; and a first bottom surface, wherein the first top surface, the first outer surface, and the first bottom surface form a first cylindrical lip of the first electrically conductive element, and wherein the distal portion of the second electrically conductive element further comprises: a second top surface; a second outer surface; and a second bottom surface, wherein the second top surface, the second outer surface, and the second bottom surface form a second cylindrical lip of the second electrically conductive element. 9. The sensor of claim 8, wherein a cross-section of the first bottom surfaces is concave in shape and wherein a cross-section of the second bottom surfaces is concave in shape. 10. The sensor of claim 8, wherein a cross-section of the first bottom surfaces is flat and wherein a cross-section of the second bottom surfaces is flat. 11. The sensor of claim 8, wherein a cross-section of the first bottom surfaces is conical in shape and wherein a cross-section of the second bottom surfaces is conical in shape. 12. The sensor of claim 1, wherein the electrically insulative element has a top surface that is tube-like in shape. 13. The sensor of claim 12, wherein the electrically insulative element has a bottom surface that defines an interior portion of the electrically insulative element that is tube-like in shape. 14. The sensor of claim 1, wherein the electrically insulative element has a top surface that is square-like in shape. 15. The sensor of claim 14, wherein the electrically insulative element has a bottom surface that defines an interior portion of the electrically insulative element that is square-like in shape. 16. The sensor of claim 1, wherein a diameter of said distal portion of said first electrically conductive element and a diameter of said distal portion of said second electrically conductive element are smaller than a diameter of said electrically insulative element. 17. The sensor of claim 1, wherein a portion of the distal portion of the first electrically conductive element, an inner portion of the second electrically conductive element, and the distal portion of the second electrically conductive element define a central chamber of the sensor, where the chamber is filled with an inert gas. 18. A method of constructing a sensor having a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and multiple electrically conductive weights, the method comprising the steps of: fitting a distal portion of the first electrically conductive element within a hollow center of the electrically insulative member, wherein a proximate portion of the first electrically conductive element remains external to the hollow center of the electrically insulative member; positioning the multiple electrically conductive weights within the hollow center of the electrically insulative member; and fitting a distal portion of the second electrically conductive element within the hollow center of the electrically insulative member, wherein a proximate portion of the second electrically conductive element remains external to the hollow center of the electrically insulative member. 19. The method of claim 18, further comprising the step of fabricating a first nub on said proximate portion of said first conductive element and a second nub on said proximate portion of said second conductive element. 20. The method of claim 18, wherein said method of constructing the sensor is performed in an inert gas. 21. The method of claim 18, further comprising the steps of: hermetically sealing the first electrically conductive element to the electrically insulative element; and hermetically sealing the second electrically conductive element to the electrically insulative element. | FIELD OF THE INVENTION The present invention is generally related to sensors, and more particularly is related to an omnidirectional tilt and vibration sensor. BACKGROUND OF THE INVENTION Many different electrical tilt and vibration switches are presently available and known to those having ordinary skill in the art. Typically, tilt switches are used to switch electrical circuits ON and OFF depending on an angle of inclination of the tilt switch. These types of tilt switches typically contain a free moving conductive element located within the switch, where the conductive element contacts two terminals when the conductive element is moved into a specific position, thereby completing a conductive path. An example of this type of tilt switch is a mercury switch. Unfortunately, it has been proven that use of Mercury may lead to environmental concerns, thereby leading to regulation on Mercury use and increased cost of Mercury containing products, including switches. To replace Mercury switches, newer switches use a conductive element capable of moving freely within a confined area. A popularly used conductive element is a single metallic ball. Tilt switches having a single metallic ball are capable of turning ON and OFF in accordance with a tilt angle of the tilt switch. Certain tilt switches also contain a ridge, a bump, or a recess, that prevents movement of the single metallic ball from a closed position (ON) to an open position (OFF) unless the tilt angle of the tilt switch is in excess of a predetermined angle. An example of a tilt switch requiring exceeding of a tilt angle of the tilt switch is provided by U.S. Pat. No. 5,136,157, issued to Blair on Aug. 4, 1992 (hereafter, the '157 patent). The '157 patent discloses a tilt switch having a metallic ball and two conductive end pieces separated by a non-conductive element. The two conductive end pieces each have two support edges. A first support edge of the first conductive end piece and a first support edge of the second conductive end piece support the metallic ball there-between, thereby maintaining electrical communication between the first conductive end piece and the second conductive end piece. Maintaining electrical communication between the first conductive end piece and the second conductive end piece keeps the tilt switch in a closed position (ON). To change the tilt switch into an open position (OFF), the metallic ball is required to be moved so that the metallic ball is not connected to both the first conductive end piece and the second conductive end piece. Therefore, changing the tilt switch into an open position (OFF) requires tilting of the '157 patent tilt switch past a predefined tilt angle, thereby removing the metallic ball from location between the first and second conductive end piece. Unfortunately, tilt switches generally are not useful in detecting minimal motion, regardless of the tilt angle. Referring to vibration switches, typically a vibration switch will have a multitude of components that are used to maintain at least one conductive element in a position providing electrical communication between a first conductive end piece and a second conductive end piece. An example of a vibration switch having a multitude of components is provided by U.S. Pat. No. 6,706,979 issued to Chou on Mar. 16, 2004 (hereafter, the '979 patent). In one embodiment of Chou, the '979 patent discloses a vibration switch having a conductive housing containing an upper wall, a lower wall, and a first electric contact body. The upper wall and the lower wall of the conductive housing define an accommodation chamber. The conductive housing contains an electrical terminal connected to the first electric contact body for allowing electricity to traverse the housing. A second electric contact body, which is separate from the conductive housing, is situated between the upper wall and lower wall of the conductive housing (i.e., within the accommodation chamber). The second electric contact body is maintained in position within the accommodation chamber by an insulating plug having a through hole for allowing an electrical terminal to fit therein. Both the first electrical contact body and the second electrical contact body are concave in shape to allow a first and a second conductive ball to move thereon. Specifically, the conductive balls are adjacently located within the accommodation chamber with the first and second electric contact bodies. Due to gravity, the '979 patent first embodiment vibration switch is typically in a closed position (ON), where electrical communication is maintained from the first electrical contact body, to the first and second conductive balls, to the second electrical contact body, and finally to the electrical terminal. In an alternative embodiment, the '979 patent discloses a vibration switch that differs from the vibration switch of the above embodiment by having the first electrical contact body separate from the conductive housing, yet still entirely located between the upper and lower walls of the housing, and an additional insulating plug, through hole and electrical terminal. Unfortunately, the many portions of the '979 patent vibration switch result in more time required for construction and assembly, in addition to higher cost. Furthermore, the '979 patent presents a vibration switch that cannot be mounted to the surface of a printed circuit board (PCB). Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies. SUMMARY OF THE INVENTION Embodiments of the present invention provide an omnidirectional tilt and vibration sensor and a method of construction thereof. Briefly described, in architecture, one embodiment of the system, among others, can be implemented as follows. The sensor contains a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and multiple electrically conductive weights. The first electrically conductive element has a first diameter on a proximate portion of the first electrically conductive element and a second diameter on a distal portion of the first electrically conductive element, where the second diameter is smaller than the first diameter. The second electrically conductive element has a first diameter on a proximate portion of the second electrically conductive element and a second diameter on a distal portion of the second electrically conductive element, where the second diameter is smaller than the first diameter. In addition, the electrically insulative element is connected to the first electrically conductive element and the second electrically conductive element, where the second distal portion of the first electrically conductive element fits within a proximate end of the electrically insulative element, where the distal portion of the second electrically conductive element fits within a distal end of the electrically insulative element, and where the proximate portion of the first electrically conductive element and the proximate portion of the second electrically conductive element are located external to the electrically insulative element. The electrically conductive weights are located within a cavity of the sensor, wherein the cavity is defined by surface of the first electrically conductive element, the electrically insulative element and the second electrically conductive element. The present invention can also be viewed as providing methods for assembling the omnidirectional tilt and vibration sensor having a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and a multiple electrically conductive weights. In this regard, one embodiment of such a method, among others, can be broadly summarized by the following steps: fitting a distal portion of the first electrically conductive element within a hollow center of the electrically insulative member, wherein a proximate portion of the first electrically conductive element remains external to the hollow center of the electrically insulative member; positioning the multiple electrically conductive weights within the hollow center of the electrically insulative member; and fitting a distal portion of the second electrically conductive element within the hollow center of the electrically insulative member, wherein a proximate portion of the second electrically conductive element remains external to the hollow center of the electrically insulative member. Other systems, methods, features, and advantages of the present invention will be or will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. BRIEF DESCRIPTION OF THE DRAWINGS Many aspects of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. FIG. 1 is an exploded perspective side view of the present omnidirectional tilt and vibration sensor, in accordance with a first exemplary embodiment of the invention. FIG. 2 is a cross-sectional side view of the first end cap of FIG. 1. FIG. 3 is a cross-sectional side view of the central member of FIG. 1. FIG. 4 is a cross-sectional side view of the second end cap of FIG. 1. FIG. 5 is a flowchart illustrating a method of assembling the omnidirectional tilt and vibration sensor of FIG. 1. FIGS. 6A and FIG. 6B are cross-sectional side views of the sensor of FIG. 1 in a closed state, in accordance with the first exemplary embodiment of the invention. FIGS. 7A, 7B, 7C, and 7D are cross-sectional side views of the sensor of FIG. 1 in an open state, in accordance with the first exemplary embodiment of the invention. FIG. 8 is a cross-sectional side view of the present omnidirectional tilt and vibration sensor, in accordance with a second exemplary embodiment of the invention. FIG. 9 is cross-sectional view of a sensor in a closed state, in accordance with a third exemplary embodiment of the invention. DETAILED DESCRIPTION The following describes an omnidirectional tilt and vibration sensor. The sensor contains a minimal number of cooperating parts to ensure ease of assembly and use. FIG. 1 is an exploded perspective side view of the present omnidirectional tilt and vibration sensor 100 (hereafter, “the sensor 100”), in accordance with a first exemplary embodiment of the invention. Referring to FIG. 1, the sensor 100 contains an electrically conductive element embodied as the first end cap 110, an electrically insulative element embodied as the central member 140, a second electrically conductive element embodied as the second end cap 160, and multiple electrically conductive weights embodied as a pair of conductive balls 190 that are spherical in shape (hereafter, conductive spheres). As mentioned above, the first end cap 110 is electrically conductive, having a proximate portion 112 and a distal portion 122. Specifically, the first end cap 110 may be constructed from a composite of high conductivity and/or low reactivity metals, a conductive plastic, or any other conductive material. FIG. 2 is a cross-sectional side view of the first end cap 110 which may be referred to for a better understanding of the location of portions of the first end cap 110. The proximate portion 112 of the first end cap 110 is circular, having a diameter D1, and having a flat end surface 114. A top surface 116 of the proximate portion 112 runs perpendicular to the flat end surface 114. A width of the top surface 116 is the same width as a width of the entire proximate portion 112 of the first end cap 110. The proximate portion 112 also contains an internal surface 118 located on a side of the proximate portion 112 that is opposite to the flat end surface 114, where the top surface 116 runs perpendicular to the internal surface 118. Therefore, the proximate portion 112 is in the shape of a disk. It should be noted that while FIG. 2 illustrates the proximate portion 112 of the first end cap 110 having a flat end surface 114 and the proximate portion 162 (FIG. 4) of the second end cap 160 having a flat surface 164 (FIG. 4), one having ordinary skill in the art would appreciate that the proximate portions 112, 162 (FIG. 4) do not require presence of a flat end surface. Instead, the flat end surfaces 114, 164 may be convex or concave. In addition, instead of being circular, the first end cap 110 and the second end cap 160 may be square-like in shape, or they may be any other shape. Use of circular end caps 110, 160 is merely provided for exemplary purposes. The main function of the end caps 110, 160 is to provide a connection to allow an electrical charge introduced to the first end cap 110 to traverse the conductive spheres 190 and be received by the second end cap 160, therefore, many different shapes and sizes of end caps 110, 160 may be used as long as the conductive path is maintained. The relationship between the top portion 116, the flat end surface 114, and the internal surface 118 described herein is provided for exemplary purposes. Alternatively, the flat end surface 114 and the internal surface 118 may have rounded or otherwise contoured ends resulting in the top surface 116 of the proximate portion 112 being a natural rounded progression of the end surface 114 and the internal surface 118. The distal portion 122 of the first end cap 110 is tube-like in shape, having a diameter D2 that is smaller than the diameter D1 of the proximate portion 112. The distal portion 122 of the first end cap 110 contains a top surface 124 and a bottom surface 126. The bottom surface 126 of the distal portion 122 defines an exterior portion of a cylindrical gap 128 located central to the distal portion 122 of the first end cap 110. A diameter D3 of the cylindrical gap 128 is smaller than the diameter D2 of the distal portion 122. Progression from the proximate portion 112 of the first end cap 110 to the distal portion 122 of the first end cap 110 is defined by a step where a top portion of the step is defined by the top surface 116 of the proximate portion 112, a middle portion of the step is defined by the internal surface 118 of the proximate portion 112, and a bottom portion of the step is defined by the top surface 124 of the distal portion 122. The distal portion 122 of the first end cap 110 also contains an outer surface 130 that joins the top surface 124 and the bottom surface 126. It should be noted that while FIG. 2 shows the cross-section of the outer surface 130 as being squared to the top surface 124 and the bottom surface 126, the outer surface 130 may instead be rounded or of a different shape. As is better shown by FIG. 2, the distal portion 122 of the first end cap 110 is an extension of the proximate portion 112 of the first end cap 110. In addition, the top surface 124, the outer surface 130, and the bottom surface 126 of the distal portion 122 form a cylindrical lip of the first end cap 110. As is also shown by FIG. 2, the distal portion 122 of the first end cap 110 also contains an inner surface 132, the diameter of which is equal to or smaller than the diameter D3 of the cylindrical gap 128. While FIG. 2 illustrates the inner surface 132 as running parallel to the flat end surface 114, as is noted hereafter, the inner surface 132 may instead be concave, conical, or hemispherical. Referring to FIG. 1, the central member 140 of the sensor 100 is tube-like in shape, having a top surface 142, a proximate surface 144, a bottom surface 146, and a distal surface 148. FIG. 3 is a cross-sectional side view of the central member 140 and may also be referred to for a better understanding of the location of portions of the central member 140. It should be noted that the central member 140 need not be tube-like in shape. Alternatively, the central member 140 may have a different shape, such as, but not limited to that of a square. The bottom surface 146 of the central member 140 defines a hollow center 150 having a diameter D4 that is just slightly larger than the diameter D2 (FIG. 2), thereby allowing the distal portion 122 of the first end cap 110 to fit within the hollow center 150 of the central member 140 (FIG. 3). In addition, the top surface 142 of the central member 140 defines the outer surface of the central member 140 where the central member 140 has a diameter D5. It should be noted that the diameter D1 (i.e., the diameter of the proximate portion 112 of the first end cap 110) is preferably slightly larger than diameter D5 (i.e., the diameter of the central member 140). Of course, different dimensions of the central member 140 and end caps 110, 160 may also be provided. In addition, when the sensor 100 is assembled, the proximate surface 144 of the central member 140 rests against the internal surface 118 of the first end cap 110. Unlike the first end cap 110 and the second end cap 160, the central member 140 is not electrically conductive. As an example, the central member 140 may be made of plastic, glass, or any other nonconductive material. In an alternative embodiment of the invention, the central member 140 may also be constructed of a material having a high melting point that is above that used by commonly used soldering materials. As is further explained in detail below, having the central member 140 non-conductive ensures that the electrical conductivity provided by the sensor 100 is provided through use of the conductive spheres 190. Specifically, location of the central member 140 between the first end cap 110 and the second end cap 160 provides a non-conductive gap between the first end cap 110 and the second end cap 160. Referring to FIG. 1, the second end cap 160 is conductive, having a proximate portion 162 and a distal portion 172. Specifically, the second end cap 160 may be constructed from a composite of high conductivity and/or low reactivity metals, a conductive plastic, or any other conductive material. FIG. 4 is a cross-sectional side view of the second end cap 160, which may be referred to for a better understanding of the location of portions of the second end cap 160. The proximate portion 162 of the second end cap 160 is circular, having a diameter D6, and having a flat end surface 164. A top surface 166 of the proximate portion 162 runs perpendicular to the flat end surface 164. A width of the top surface 166 is the same width as a width of the entire proximate portion 162 of the second end cap 160. The proximate portion 162 also contains an internal surface 168 located on a side of the proximate portion 162 that is opposite to the flat end surface 164, where the top surface 166 runs perpendicular to the internal surface 168. Therefore, the proximate portion 162 is in the shape of a disk. The relationship between the top portion 166, the flat end surface 164, and the internal surface 168 described herein is provided for exemplary purposes. Alternatively, the flat end surface 164 and the internal surface 168 may have rounded or otherwise contoured ends resulting in the top surface 166 of the proximate portion 162 being a natural rounded progression of the end surface 164 and the internal surface 168. The distal portion 172 of the second end cap 160 is tube-like is shape, having a diameter D7 that is smaller than the diameter D6 of the proximate portion 162. The distal portion 172 of the second end cap 160 contains a top surface 174 and a bottom surface 176. The bottom surface 176 of the distal portion 172 defines an exterior portion of a cylindrical gap 178 located central to the distal portion 172 of the second end cap 160. A diameter D8 of the cylindrical gap 178 is smaller than the diameter D7 of the distal portion 172. Progression from the proximate portion 162 of the second end cap 160 to the distal portion 172 of the second end cap 160 is defined by a step where a top portion of the step is defined by the top surface 166 of the proximate portion 162, a middle portion of the step is defined by the internal surface 168 of the proximate portion 162, and a bottom portion of the step is defined by the top surface 174 of the distal portion 172. The distal portion 172 of the second end cap 160 also contains an outer surface 180 that joins the top surface 174 and the bottom surface 176. It should be noted that while FIG. 4 shows the cross-section of the outer surface 180 as being squared to the top surface 174 and the bottom surface 176, the outer surface 180 may instead be rounded or of a different shape. As is better shown by FIG. 4, the distal portion 172 of the second end cap 160 is an extension of the proximate portion 162 of the second end cap 160. In addition, the top surface 174, the outer surface 180, and the bottom surface 176 of the distal portion 172 form a cylindrical lip of the second end cap 160. As is also shown by FIG. 4, the distal portion 172 of the second end cap 160 also contains an inner surface 182, the diameter of which is equal to or smaller than the diameter D8 of the cylindrical gap 178. While FIG. 4 illustrates the inner surface 182 as running parallel to the flat end surface 164, the inner surface 182 may instead be concave, conical, or hemispherical. It should be noted that dimensions of the second end cap 160 are preferably the same as dimensions of the first end cap 110. Therefore, the diameter D4 of the central member 140 hollow center 150 is also just slightly larger that the diameter D7 of the second end cap 160, thereby allowing the distal portion 172 of the second end cap 160 to fit within the hollow center 150 of the central member 140. In addition, the diameter D6 (i.e., the diameter of the proximate portion 162 of the second end cap 160) is preferably slightly larger that diameter D5 (i.e., the diameter of the central member 140). Further, when the sensor 100 is assembled, the distal surface 148 of the central member 140 rests against the internal surface 168 of the second end cap 160. Referring to FIG. 1, the pair of conductive spheres 190, including a first conductive sphere 192 and a second conductive sphere 194, fit within the central member 140, within a portion of the cylindrical gap 128 of the first distal portion 122 of the first end cap 110, and within a portion of the cylindrical gap 178 of the second end cap 160. Specifically, the inner surface 132, bottom surface 126, and outer surface 130 of the first end cap 110, the bottom surface 146 of the central member 140, and the inner surface 182, bottom surface 176, and outer surface 180 of the second end cap 160 form a central cavity 200 of the sensor 100 where the pair of conductive spheres 190 are confined. Further illustration of location of the conductive spheres 190 is provided and illustrated with regard to FIGS. 6A, 6B, and 7A-7D. It should be noted that, while the figures in the present disclosure illustrate both of the conductive spheres 190 as being substantially symmetrical, alternatively, one sphere may be larger that the other sphere. Specifically, as long as the conductive relationships described herein are maintained, the conductive relationships may be maintained by both spheres being larger, one sphere being larger than the other, both spheres being smaller, or one sphere being smaller. It should be noted that the conductive spheres 190 may instead be in the shape of ovals, cylinders, or any other shape that permits motion within the central cavity in a manner similar to that described herein. Due to minimal components, assembly of the sensor 100 is quite simplistic. Specifically, there are four components, namely, the first end cap 110, the central member 140, the conductive spheres 190, and the second end cap 160. FIG. 5 is a flowchart illustrating a method of assembling the omnidirectional tilt and vibration sensor 100 of FIG. 1. It should be noted that any process descriptions or blocks in flowcharts should be understood as representing modules, segments, portions of code, or steps that include one or more instructions for implementing specific logical functions in the process, and alternate implementations are included within the scope of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention. As is shown by block 202, the distal portion 122 of the first end cap 110 is fitted within the hollow center 150 of the central member 140 so that the proximate surface 144 of the central member 140 is adjacent to or touching the internal surface 118 of the first end cap 110. The conductive spheres 190 are then positioned within the hollow center 150 of the central member 140 and within a portion of the cylindrical gap 128 (block 204). The distal portion 172 of the second end cap 160 is then fitted within the hollow center 150 of the central member 140, so that the distal surface 148 of the central member 140 is adjacent to or touching the internal surface 168 of the second end cap 160 (block 206). In accordance with an alternative embodiment of the invention, the sensor 100 may be assembled in an inert gas, thereby creating an inert environment within the central cavity 200, thereby reducing the likelihood that the conductive spheres 190 will oxidize. As is known by those having ordinary skill in the art, oxidizing of the conductive spheres 190 would lead to a decrease in the conductive properties of the conductive spheres 190. In addition, in accordance with another alternative embodiment of the invention, the first end cap 110, the central member 140, and the second end cap 160 may be joined by a hermetic seal, thereby preventing any contaminant from entering the central cavity 200. The sensor 100 has the capability of being in a closed state or an open state, depending on location of the conductive spheres 190 within the central cavity 200 of the sensor 100. FIG. 6A and FIG. 6B are cross-sectional views of the sensor 100 of FIG. 1 in a closed state, in accordance with the first exemplary embodiment of the invention. In order for the sensor 100 to be maintained in a closed state, an electrical charge introduced to the first end cap 110 is required to traverse the conductive spheres 190 and be received by the second end cap 160. Referring to FIG. 6A, the sensor 100 is in a closed state because the first conductive sphere 192 is touching the bottom surface 126 of the first end cap 110, the conductive spheres 192, 194 are touching, and the second conductive sphere 194 is touching the bottom surface 176 and inner surface 182 of the second end cap 162, thereby providing a conductive path from the first end cap 110, through the conductive spheres 190, to the second end cap 160. Referring to FIG. 6B, the sensor 100 is in a closed state because the first conductive sphere 192 is touching the bottom surface 126 and inner surface 132 of the first end cap 110, the conductive spheres 192, 194 are touching, and the second conductive sphere 194 is touching the bottom surface 176 of the second end cap 162, thereby providing a conductive path from the first end cap 110, through the conductive spheres 190, to the second end cap 160. Of course, other arrangements of the first and second conductive spheres 190 within the central cavity 200 of the sensor 100 may be provided as long as the conductive path from the first end cap 110 to the conductive spheres 190, to the second end cap 160 is maintained. FIGS. 7A-FIG. 7D are cross-sectional views of the sensor 100 of FIG. 1 in an open state, in accordance with the first exemplary embodiment of the invention. In order for the sensor 100 to be maintained in an open OFF state, an electrical charge introduced to the first end cap 110 cannot traverse the conductive spheres 190 and be received by the second end cap 160. Referring to FIGS. 7A-7D, each of the sensors 100 displayed are in an open state because the first conductive sphere 192 is not in contact with the second conductive sphere 194. Of course, other arrangements of the first and second conductive spheres 190 within the central cavity 200 of the sensor 100 may be provided as long as no conductive path is provided from the first end cap 110 to the conductive spheres 190, to the second end cap 160. FIG. 8 is a cross-sectional side view of the present omnidirectional tilt and vibration sensor 300, in accordance with a second exemplary embodiment of the invention. The sensor 300 of the second exemplary embodiment of the invention contains a first nub 302 located on the flat end surface 114 of the first end cap 110 and a second nub 304 located on a flat end surface 164 of the second end cap 160. The nubs 302, 304 provide a conductive mechanism for allowing the sensor 300 to connect to a printed circuit board (PCB) where the PCB has an opening cut into it allowing the sensor to recess into the opening. Specifically, dimensions of the sensor in accordance with the first exemplary embodiment and the second exemplary embodiment of the invention may be selected so as to allow the sensor to fit within the opening on the PCB. Adjacent to the opening, there may be a first terminal and a second terminal. By using the nubs 302, 304, fitting the sensor 300 into the opening may press the first nub 302 against the first terminal and the second nub 304 against the second terminal. Those having ordinary skill in the art would understand the basic structure of a PCB landing pad, therefore, further explanation of the landing pad is not provided herein. It should be noted that the sensor of the first and second embodiments have the same basic rectangular shape, thereby contributing to ease of preparing a PCB for receiving the sensor 100, 300. Specifically, an opening may be cut in a PCB the size of the sensor 100 (i.e., the size of the first and second end caps 110, 160 and the central member 140) so that the sensor 100 can drop into the opening, where the sensor is prevented from falling through the opening when caught by the nubs 302, 304 that land on connection pads. In the first exemplary embodiment of the invention, where there are no nubs, the end caps 110, 160 may be directly mounted to a first and a second landing pad on the surface of the PCB. In accordance with another alternative embodiment of the invention, the two conductive spheres may be replaced by more than two conductive spheres, or other shapes that are easily inclined to roll when the sensor 100 is moved. FIG. 9 is cross-sectional view of a sensor 400 in a closed state, in accordance with a third exemplary embodiment of the invention. As is shown by FIG. 9, an inner surface 412 of a first end cap 410 is concave is shape. In addition, an inner surface 422 of a second end cap 420 is concave in shape. The sensor 400 of FIG. 9 also contains a first nub 430 and a second nub 432 that function in a manner similar to the nubs 302, 304 in the second exemplary embodiment of the invention. Having a sensor 400 with concave inner surfaces 412, 422 keeps the sensor 400 in a normally closed state due to the shape of the inner surfaces 412, 422 in combination with gravity causing the conductive spheres 192, 194 to be drawn together. It should be emphasized that the above-described embodiments of the present invention are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Many different electrical tilt and vibration switches are presently available and known to those having ordinary skill in the art. Typically, tilt switches are used to switch electrical circuits ON and OFF depending on an angle of inclination of the tilt switch. These types of tilt switches typically contain a free moving conductive element located within the switch, where the conductive element contacts two terminals when the conductive element is moved into a specific position, thereby completing a conductive path. An example of this type of tilt switch is a mercury switch. Unfortunately, it has been proven that use of Mercury may lead to environmental concerns, thereby leading to regulation on Mercury use and increased cost of Mercury containing products, including switches. To replace Mercury switches, newer switches use a conductive element capable of moving freely within a confined area. A popularly used conductive element is a single metallic ball. Tilt switches having a single metallic ball are capable of turning ON and OFF in accordance with a tilt angle of the tilt switch. Certain tilt switches also contain a ridge, a bump, or a recess, that prevents movement of the single metallic ball from a closed position (ON) to an open position (OFF) unless the tilt angle of the tilt switch is in excess of a predetermined angle. An example of a tilt switch requiring exceeding of a tilt angle of the tilt switch is provided by U.S. Pat. No. 5,136,157, issued to Blair on Aug. 4, 1992 (hereafter, the '157 patent). The '157 patent discloses a tilt switch having a metallic ball and two conductive end pieces separated by a non-conductive element. The two conductive end pieces each have two support edges. A first support edge of the first conductive end piece and a first support edge of the second conductive end piece support the metallic ball there-between, thereby maintaining electrical communication between the first conductive end piece and the second conductive end piece. Maintaining electrical communication between the first conductive end piece and the second conductive end piece keeps the tilt switch in a closed position (ON). To change the tilt switch into an open position (OFF), the metallic ball is required to be moved so that the metallic ball is not connected to both the first conductive end piece and the second conductive end piece. Therefore, changing the tilt switch into an open position (OFF) requires tilting of the '157 patent tilt switch past a predefined tilt angle, thereby removing the metallic ball from location between the first and second conductive end piece. Unfortunately, tilt switches generally are not useful in detecting minimal motion, regardless of the tilt angle. Referring to vibration switches, typically a vibration switch will have a multitude of components that are used to maintain at least one conductive element in a position providing electrical communication between a first conductive end piece and a second conductive end piece. An example of a vibration switch having a multitude of components is provided by U.S. Pat. No. 6,706,979 issued to Chou on Mar. 16, 2004 (hereafter, the '979 patent). In one embodiment of Chou, the '979 patent discloses a vibration switch having a conductive housing containing an upper wall, a lower wall, and a first electric contact body. The upper wall and the lower wall of the conductive housing define an accommodation chamber. The conductive housing contains an electrical terminal connected to the first electric contact body for allowing electricity to traverse the housing. A second electric contact body, which is separate from the conductive housing, is situated between the upper wall and lower wall of the conductive housing (i.e., within the accommodation chamber). The second electric contact body is maintained in position within the accommodation chamber by an insulating plug having a through hole for allowing an electrical terminal to fit therein. Both the first electrical contact body and the second electrical contact body are concave in shape to allow a first and a second conductive ball to move thereon. Specifically, the conductive balls are adjacently located within the accommodation chamber with the first and second electric contact bodies. Due to gravity, the '979 patent first embodiment vibration switch is typically in a closed position (ON), where electrical communication is maintained from the first electrical contact body, to the first and second conductive balls, to the second electrical contact body, and finally to the electrical terminal. In an alternative embodiment, the '979 patent discloses a vibration switch that differs from the vibration switch of the above embodiment by having the first electrical contact body separate from the conductive housing, yet still entirely located between the upper and lower walls of the housing, and an additional insulating plug, through hole and electrical terminal. Unfortunately, the many portions of the '979 patent vibration switch result in more time required for construction and assembly, in addition to higher cost. Furthermore, the '979 patent presents a vibration switch that cannot be mounted to the surface of a printed circuit board (PCB). Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies. | <SOH> SUMMARY OF THE INVENTION <EOH>Embodiments of the present invention provide an omnidirectional tilt and vibration sensor and a method of construction thereof. Briefly described, in architecture, one embodiment of the system, among others, can be implemented as follows. The sensor contains a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and multiple electrically conductive weights. The first electrically conductive element has a first diameter on a proximate portion of the first electrically conductive element and a second diameter on a distal portion of the first electrically conductive element, where the second diameter is smaller than the first diameter. The second electrically conductive element has a first diameter on a proximate portion of the second electrically conductive element and a second diameter on a distal portion of the second electrically conductive element, where the second diameter is smaller than the first diameter. In addition, the electrically insulative element is connected to the first electrically conductive element and the second electrically conductive element, where the second distal portion of the first electrically conductive element fits within a proximate end of the electrically insulative element, where the distal portion of the second electrically conductive element fits within a distal end of the electrically insulative element, and where the proximate portion of the first electrically conductive element and the proximate portion of the second electrically conductive element are located external to the electrically insulative element. The electrically conductive weights are located within a cavity of the sensor, wherein the cavity is defined by surface of the first electrically conductive element, the electrically insulative element and the second electrically conductive element. The present invention can also be viewed as providing methods for assembling the omnidirectional tilt and vibration sensor having a first electrically conductive element, a second electrically conductive element, an electrically insulative element, and a multiple electrically conductive weights. In this regard, one embodiment of such a method, among others, can be broadly summarized by the following steps: fitting a distal portion of the first electrically conductive element within a hollow center of the electrically insulative member, wherein a proximate portion of the first electrically conductive element remains external to the hollow center of the electrically insulative member; positioning the multiple electrically conductive weights within the hollow center of the electrically insulative member; and fitting a distal portion of the second electrically conductive element within the hollow center of the electrically insulative member, wherein a proximate portion of the second electrically conductive element remains external to the hollow center of the electrically insulative member. Other systems, methods, features, and advantages of the present invention will be or will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. | 20050118 | 20060627 | 20060720 | 97877.0 | H01H3514 | 1 | HOMZA, LISA NHUNG | OMNIDIRECTIONAL TILT AND VIBRATION SENSOR | SMALL | 0 | ACCEPTED | H01H | 2,005 |
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11,037,574 | ACCEPTED | Albuterol and ipratropium inhalation solution, system, kit and method for relieving symptoms of chronic obstructive pulmonary disease | The present invention relates to a dual bronchodilator inhalation solution, system, kit and method for relieving bronchospasm in patients suffering from chronic obstructive pulmonary disease (COPD). In one alternative embodiment, the solution of the present invention is a prepackaged, sterile, premixed, premeasured single unit dose of albuterol and ipratropium bromide for patients suffering from COPD. The present solution may be free of antimicrobial preservatives, such as benzalkonium chloride. In another alternative embodiment, the solution of the present invention comprises about 2.50 mg albuterol and about 0.50 mg ipratropium bromide in a 0.5 ml volume. | 1. A system for inducing bronchodialation or providing relief of bronchospasm in an individual suffering from chronic obstructive pulmonary disease, said system comprising: (a) at least one single dispensing container; said container prefilled with about 0.1 ml to about 2.0 ml of a premixed, premeasured, aqueous inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium bromide; wherein said amount of ipratropium bromide ranges from about 0.01 mg to about 1.0 mg; the solution being suitable for nebulizer. 2. The system of claim 1, wherein the container is prefilled with about 0.05 ml to about 0.5 ml of the inhalation solution. 3. The system of claim 1, wherein one container is prefilled with about 0.1 ml to about 0.5 ml of the inhalation solution. 4. The system of claim 1, wherein the container is prefilled with about 0.5 ml of the inhalation solution. 5. The system of claim 1, wherein said amount of albuterol ranges from about 2.0 mg to about 3.0 mg. 6. The system of claim 1, wherein the albuterol is albuterol base, and said amount of albuterol base is about 2.5 mg and the amount of ipratropium is about 0.5 mg. 7. The system of claim 1, wherein the inhalation solution in each of the one or more containers is sterile. 8. The system of claim 1, wherein the inhalation solution in each of the one or more containers is free of benzalkonium chloride. 9. The system of claim 1, wherein the system further comprises a label which indicates that the inhalation solution can be used to relieve broncospasm associated with chronic obstructive pulmonary disease. 10. The system of claim 9, wherein said label comprises instructions for using the solution to relieve said bronchospasm. 11. The system of claim 9, wherein said label providing prescribing information comprising efficacy, dosage, administration, contraindication and adverse reaction information pertaining to the inhalation solution in the container. 12. The system of claim 11, wherein the adverse reaction information comprises information indicating that lung disease, bronchitis, diarrhea, and pharyngitis may occur after administrating the inhalation solution in the container. 13. The system of claim 11, wherein the contradiction information comprises information indicating that the inhalation solution in the container is contraindicated for humans with hypersensitivity to any of the ingredients in the inhalation solution. 14. The system of claim 11, wherein the contraindication information comprises information indicating that the inhalation solution in the container is contraindicated for humans with hypersensitivity to atrophy and derivatives thereof. 15. A system for reducing medication error, reducing nebulizer treatment time and enhancing therapeutic compliance of an individual suffering from chronic obstructive pulmonary disease, the prepackaged therapeutic system comprising: (a) one or more dispensing containers; the one or more containers each prefilled with about 1 ml to about 2 ml of a sterile, benzlakonium chloride-free, premixed, premeasured aqueous inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide; wherein the dosage of albuterol is about 2.5 mg and the dosage of ipratropium bromide is about 0.5 mg; the inhalation solution in each of the one ore more containers is suitable for nebulization in a nebulizer; the inhalation solution in each of the one or more containers is stable; (b) one or more labels with indicia thereon, the indicia comprising efficacy dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one or more containers; and (c) wherein the contraindication data comprises data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to any of the ingredient contained in the inhalation solution; (d) wherein the dosage and administration data comprises data indicating that the recommended dose of the inhalation solution in each of the one or more containers is about 2.5 mg of albuterol and about 0.5 mg ipratropium bromide; and (e) wherein the adverse reaction data comprises data indicating that lung disease, bronchitis, diarrhea or phyaryngitis may occur after administration of the inhalation solution. 16. The system of claim 15, wherein the albuterol is in the form of an acid addition salt. 17. The system of claim 15, wherein the acid addition salt of the albuterol is albuterol sulfate. 18. A method of inducing bronchodialation or providing relief of bronchospasm in an individual suffering from chronic obstructive pulmonary disease, said method comprising the step of: (a) administrating to the individual at least one single dispensing containers; the one or more containers each prefilled with about 0.1 ml to about 2.0 ml of a premixed, premeasured aqueous inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide; wherein the amount of albuterol is about 0.6 mg to about 5.0 mg and the amount of ipratropium bromide is about 0.1 mg to about 1.0 mg; the inhalation solution in each of the one ore more containers is suitable for nebulization in a nebulizer. 19. The method of claim 18, wherein each of the one ore more containers is prefilled with about 0.05 ml to about 0.5 ml of the inhalation solution. 20. The method of claim 18, wherein each of the one or more containers is prefilled with about 0.1 ml to about 0.5 ml of the inhalation solution. 21. The method of claim 18, wherein each of the one or more containers is prefilled with about 0.5 ml of the inhalation solution. 22. The method of claim 18, further comprising the step of providing dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one ore more containers. 23. The method of claim 22, wherein the step of providing contraindication data comprises data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to one ore more of the ingredients in the inhalation solution. 24. The method of claim 22, wherein the step of providing adverse reaction data comprises data indicating that any disease, bronchitis, diarrhea or laryngitis may occur after administrating the inhalation solution in the one or more containers. 25. The method of claim 22, wherein the albuterol is albuterol base. 26. The method of claim 22, wherein the albuterol is albuterol sulfate. 27. A method of inducing bronchodialation or providing relief of bronchospasm, reducing medication error, reducing nebulization treatment time and enhancing therapeutic compliance of an individual suffering from chronic obstructive pulmonary disease, said method comprising the steps: (a) placing the inhalation solution of claim 1 into a chamber of a nebulizer, said nebulizer having a mouthpiece or facemask associated with the chamber of the nebulizer; (b) positioning the mouthpiece or facemask in close proximity to the individual's mouth or face; (c) passing the inhalation solution in a mist form from the nebulizer chamber through the mouthpiece or facemask to the individual while the individual breathes into the mouthpiece or facemask; and (d) the individual breathing into the mouthpiece or facemask until the nebulization treatment is finished. 28. The method of claim 27, wherein the nebulization treatment is finished when at least substantially all the mist is removed from the nebulizer chamber. 29. The method of claim 27, wherein at least substantially all the mist is removed from the nebulizer chamber in less than 12 minutes. 30. The method of claim 27, wherein at substantially all the mist is removed from the nebulizer chamber in less than 10 minutes. 31. The method of claim 27, wherein at least substantially all the mist is removed from the nebulizer chamber in less than 8 minutes. 32. The method of claim 27, wherein at least substantially all the mist is removed from the nebulizer chamber in less than 6 minutes. 33. The method of claim 27, wherein at least substantially all the mist is removed from the nebulizer chamber in less than 4 minutes. 34. A method of reducing medication error and enhancing therapeutic compliance in an individual suffering from chronic obstructive pulmonary disease (COPD), said method comprising the steps of: (a) administering to the individual at least one single dispensing container wherein the container is prefilled with about 0.1 ml to 0.5 ml of a sterile, benzalkonium chloride-free, premixed, premeasured aqueous inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol base and ipratropium bromide; wherein the amount of albuterol base is 2.5 mg and the amount of ipratropium bromide is about 0.5 mg; the inhalation solution in the container is suitable for nebulization in a nebulizer; the inhalation solution in the container is stable, in that the inhalation solution is therapeutically effective following storage for 12 months at 25° C.; and (b) providing dosage information pertaining to the inhalation solution in the container; and (c) providing administration, information, wherein said administration information comprises instructions for the use of the unit dose of albuterol and ipratropium to treat COPD. 35. The method of claim 34, wherein the dispensing container is prefilled with 0.1 ml to 0.4 ml of the inhalation solution. 36. The method of claim 34, wherein the dispensing container is prefilled with 0.1 ml to 0.3 ml of the inhalation solution. 37. The method of claim 34, wherein the dispensing container is prefilled with 0.1 ml to 0.5 ml of the inhalation solution. | I. CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application Ser. No. 10/417,723 filed Apr. 15, 2003, and is also a continuation-in-part of International Application PCT/US04/017705 filed Apr. 15, 2004. Both applications are continuations-in-part of U.S. application Ser. No. 10/162,460 filed Jun. 3, 2002, which is a continuation-in-part of U.S. application Ser. No. 10/034,657 filed Dec. 28, 2001 (now abandoned), and International Application PCT/US02/33353 filed Oct. 18, 2002, which both claim priority under 35 U.S.C. § 119 from U.S. Provisional Application Ser. No. 60/346,078 filed Oct. 26, 2001. The entire disclosure of each of these prior applications is incorporated herein by reference in its entirety. Both above-identified international applications were published in English under PCT Article 2(2) under Publication Nos. WO04/091536 and WO03/037159, respectively. II. FIELD OF THE INVENTION The present invention relates to a combination bronchodilator therapy for relieving symptoms associated with chronic obstructive pulmonary disease, and methods of using the same. The present invention also relates to a method of making said combination bronchodilator. III. BACKGROUND OF INVENTION Chronic obstructive pulmonary disease (COPD) is a slowly progressive airway disease that produces a decline in lung function that is not fully reversible. The airway limitation in COPD is associated with an abnormal inflammatory response of the lungs to noxious particles or gases. In the U.S., an estimated 16 million Americans have been diagnosed with some form of COPD, and as many as 16 million others have the condition but have not yet been diagnosed. According to the U.S. Centers for Disease Control and Prevention, COPD is the fourth leading cause of death in the U.S. (behind heart disease, cancer and stroke), claiming the lives of 112,000 Americans annually. In terms of health care utilization, the number of physician visits for COPD in the U.S. increased from 9.3 million to 16 million between 1985 and 1995. The number of hospitalizations for COPD in 1995 was estimated to be about 500,000. Although prevalence, hospitalization and death rates for COPD are higher in men than women, death rates have risen faster in women in recent years. COPD is clearly a major and growing health care threat in the U.S. and throughout the rest of the world. In the prior art, antimicrobial agents such as benzalkonium chloride (BAC) are often present in inhalation solutions used to treat COPD. The presence of BAC in these solutions generally does not affect the short-term (single dose) bronchodilator response. However, case reports suggest that repeated use of COPD treatments with BAC may result in paradoxic bronchoconstriction. When inhaled by COPD subjects, BAC may also cause dose-dependent bronchoconstriction. Despite these side effects, many commercially available inhalation solutions contain BAC. In addition, treatments for COPD often come in multiple dosage units and must be diluted to specific concentrations suitable for treating patients. This poses several problems. For instance, COPD treatments requiring administration of a single dose unit from multiple dosage units sometimes lack proper mixing or diluting instructions, or the instructions for preparing and using the COPD treatment may be hard to follow or can be easily lost. Of even greater import is haphazard diluting or mixing of COPD medications, which can result in administering the wrong dosage. This could be especially harmful for patients less tolerant to higher dosages of asthma medications. Incorrect mixing can also result in treatment failure such that additional medical attention is required, thereby increasing the time, expense and personnel costs associated with therapy. There is, therefore, a need for an improved inhalation solution, system, kit and method for relieving symptoms associated with COPD. IV. SUMMARY OF THE INVENTION One object of the present invention is to provide a dual bronchodilator inhalation solution to relieve bronchospasm in patients suffering from COPD. Another object of the present invention is to provide a prepackaged, sterile, premixed, premeasured albuterol and ipratropium inhalation solution for the relief of bronchospasm in patients suffering from COPD. It is yet another object of the present invention to provide a BAC-free albuterol and ipratropium inhalation solution to treat bronchospasm associated with COPD. A further object of the present invention is to provide a method of administering an albuterol and ipratropium inhalation formulation for relief of bronchospasm associated with COPD. An additional object of the present invention is to provide a kit and/or system for administering a dual bronchodilator to relieve bronchospasm associated with COPD. A further object of the present invention is to provide a process for making an albuterol and ipratropium inhalation solution for use in relieving bronchospasm associated with COPD. Another object of the invention includes a device for use in relieving the symptoms of COPD. Other objects, features and advantages of the present invention will be apparent to those of ordinary skill in the art in view of the following detailed description of the invention and accompanying drawings. V. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1-4 depict a non-limiting example of administering the inhalation solution of the present invention by a nebulizer. FIG. 5 depicts a non-limiting example of a unified prepackaged kit or system of the present invention. FIG. 6 depicts a non-limiting example of one or more pre-filled containers comprising the inhalation system of the present invention. VI. DETAILED DESCRIPTION OF THE INVENTION Albuterol The present invention relies on the bronchodilation effects of albuterol to provide relief from symptoms associated with COPD. As used herein, the term “albuterol” includes, but is not limited to, any form of albuterol that is capable of producing a desired bronchodilation effect in patients, including, but not limited to, all tautomeric forms, enantomeric forms, stereoisomers, anhydrides, acid addition salts, base salts, solvates, analogues and derivatives of albuterol, or any mixture thereof. In the present invention, acceptable salts of albuterol may include, but are not limited to, hydrochloride, sulfate, maleate, tartrate, citrate and the like. These salts are described in U.S. Pat. No. 3,644,353, which is incorporated herein by reference in its entirety. In the present invention, the preferred salt of albuterol is sulfate. In an alternative embodiment, the inhalation solution of the present invention comprises the sulfate salt of racemic albuterol, or it may comprise at least substantially of a single isomer of albuterol. Albuterol sulfate is a relatively selective beta-2-adrenergic bronchodilator with an empirical formula of C13H21NO3. The chemical name for albuterol sulfate is α1-[(tert-butylamino)methyl]-4-hydroxy-m-xylene-α,α′-diol sulfate (2:1)(salt), and its established chemical structure is as follows: Ipratropium The present invention also relies on the bronchodilation effect of ipratropium to provide relief from symptoms associated with COPD. Ipratropium is an anticholinergic bronchodilator. As used herein, the term “ipratropium” includes, but is not limited to, any form of ipratropium which is capable of producing a desired bronchodilation effect in patients suffering from COPD, including, but not limited to, all tautomeric forms, enantomeric forms, stereoisomers, anhadrides, acid addition salts, base salts, salvates, analogues, derivatives of ipratropium, or any mixture thereof. In the present invention, acceptable salts of ipratropium may include, but are not limited to, halide salts such as bromide, chloride and iodide. These and other acceptable salts are described in U.S. Pat. No. 3,505,337, which is incorporated herein by reference in its entirety. In one alternative embodiment, the inhalation solution of the present invention comprises racemic ipratropium bromide, or it may comprise at least substantially of a single isomer of ipratropium bromide. In one embodiment of the present invention, the preferred salt of ipratropium is bromide, which is chemically described as 8-azoniabicyclo [3.2.1]-octane, 3-(3, hydroxyl-1-oxo-2-phenylpropoxy)-8methyl-8-(1-methylethyl)-bromide, monohydrate, (endo, syn)-, (±)-. Ipratropium bromide has a molecular weight of 430.4 and the empirical formula C20H30BrNO3.H2O. It is freely soluble in water and lower alcohol, and is insoluble in lipohilic solvents such as ether, chloroform and fluorocarbon. The established chemical structure of ipratropium bromide is as follows: In the present invention, the albuterol and ipratropium may be provided in a variety of pharmaceutically acceptable vehicles, including, but not limited to, water or any other aqueous solution comprising a pharmaceutically acceptable amount of an osmotic agent. In one alternative embodiment, the inhalation solution of the present invention comprises a therapeutically effective amount of albuterol and ipratropium. As used herein, the phrase “therapeutically effective amount of albuterol and/or ipratropium” means a safe and tolerable amount of both compounds, as based on industry and/or regulatory standards. Such amount being sufficient to effectively induce bronchodilation and/or provide relief of bronchospasm in patients suffering form COPD. In the inhalation solution of the present invention, a therapeutically effective amount of albuterol may include from about 0.63 mg to about 4.2 mg albuterol. Here, the potency of the albuterol is equivalent to from about 0.75 mg to about 5 mg of albuterol sulfate. In an alternative embodiment, a therapeutically effective amount of albuterol may include about 2.5 mg albuterol. In another alternative embodiment of the present invention, a therapeutically effective amount of albuterol may include from about 0.60 mg to about 5.0 mg albuterol, including the following intermediate ranges of albuterol: about 0.60 mg to about 0.70 mg; about 0.71 mg to about 0.80 mg; about 0.81 mg to about 0.90 mg; about 0.91 mg to about 1.00 mg; about 1.01 mg to about 1.10 mg; about 1.11 mg to about 1.20 mg; about 1.21 mg to about 1.30 mg; about 1.31 mg to about 1.40 mg; about 1.41 mg to about 1.50 mg; about 1.51 mg to about 1.60 mg; about 1.61 mg to about 1.70 mg; about 1.71 mg to about 1.80 mg; about 1.81 mg to about 1.90 mg; about 1.91 mg to about 2.00 mg; about 2.01 mg to about 2.10 mg; about 2.11 mg to about 2.20 mg; about 2.21 mg to about 2.30 mg; about 2.31 mg to about 2.40 mg; about 2.41 mg to about 2.50 mg; about 2.51 mg to about 2.60 mg; about 2.61 mg to about 2.70 mg; about 2.71 mg to about 2.80 mg; about 2.81 mg to about 2.90 mg; about 2.91 mg to about 3.00; about 3.01 to about 3.10; about 3.11 to about 3.20; about 3.21 to about 3.30 mg; about 3.31 mg to about 3.40 mg; about 3.41 mg to about 3.50 mg; about 3.51 mg to about 3.60 mg; about 3.61 to about 3.70 mg; about 3.71 to about 3.80 mg; about 3.81 mg to about 3.90 mg; about 3.91 mg to about 4.0 mg; about 4.01 mg to about 4.10 mg; about 4.11 mg to about 4.20 mg; about 4.21 mg to about 4.30 mg; about 4.31 mg to about 4.40 mg; about 4.41 mg to about 4.50 mg; about 4.51 mg to about 4.60 mg; about 4.61 mg to about 4.70 mg; about 4.71 mg to about 4.80 mg; about 4.81 mg to about 4.90 mg; about 4.91 mg to about 5.00 mg. In another alternative embodiment of the present invention, a therapeutically effective amount of albuterol may include from about 0.75 mg to about 5.0 mg albuterol sulfate, including the following intermediate amounts: about 0.75 mg to about 0.80 mg; about 0.81 to about 0.90 mg; about 0.91 mg to about 1.00 mg; about 1.01 mg to about 1.10 mg; about 1.11 mg to about 1.20 mg; about 1.21 mg to about 1.30 mg; about 1.31 mg to about 1.40 mg; about 1.41 mg to about 1.50 mg; about 1.51 mg to about 1.60 mg; about 1.61 mg to about 1.70 mg; about 1.71 mg to about 1.80 mg; about 1.81 mg to about 1.90 mg; about 1.91 mg to about 2.00 mg; about 2.01 mg to about 2.10 mg; about 2.11 mg to about 2.20 mg; about 2.21 mg to about 2.30 mg; about 2.31 mg to about 2.40 mg; about 2.41 mg to about 2.50 mg; about 2.51 mg to about 2.60 mg; about 2.61 mg to about 2.70 mg; about 2.71 mg to about 2.80 mg; about 2.81 mg to about 2.90 mg; about 2.91 mg to about 3.00; about 3.01 to about 3.10; about 3.11 to about 3.20; about 3.21 to about 3.30 mg; about 3.31 mg to about 3.40 mg; about 3.41 mg to about 3.50 mg; about 3.51 mg to about 3.60 mg; about 3.61 to about 3.70 mg; about 3.71 to about 3.80 mg; about 3.81 mg to about 3.90 mg; about 3.91 mg to about 4.0 mg; about 4.01 mg to about 4.10 mg; about 4.11 mg to about 4.20 mg; about 4.21 mg to about 4.30 mg; about 4.31 mg to about 4.40 mg; about 4.41 mg to about 4.50 mg; about 4.51 mg to about 4.60 mg; about 4.61 mg to about 4.70 mg; about 4.71 mg to about 4.80 mg; about 4.81 mg to about 4.90 mg; about 4.91 mg to about 5.00 mg. In another alternative embodiment of the present invention, a therapeutically effective amount of albuterol may include from about 0.020% to about 0.14% by weight albuterol, including the following intermediate ranges: about 0.020 wt % to about 0.029 wt %; about 0.030 wt % to about 0.039 wt %; about 0.040 wt % to about 0.049 wt %; about 0.050 wt % to about 0.059 wt %;about 0.060 wt % to about 0.069 wt %; about 0.070 wt % to about 0.079 wt %; about 0.080 wt % to about 0.089 wt %; about 0.090 wt % to about 0.099 wt %; about 0.10 wt % to about 0.14 wt %. In another alternative embodiment, a therapeutically effective amount of albuterol may include from about 0.1% to about 5.0% by weight albuterol, including the following intermediate ranges: about 0.2% to about 0.5%; about 0.5% to about 0.75%; about 0.75% to about 1.0%; 1.0% to about 1.25%; about 1.25% to about 1.50%; 1.50% to about 1.75%; 1.75% to about 2.0%; about 2.0% to about 2.25%; about 2.25% to about 2.50%; 2.50% to about 2.75%; to about 2.75% to about 3.0%; about 3.0% to about 3.5%; about 3.5% to about 4.0%; 4.0% to about 4.5%; about 4.5% to about 5.0%. In alternative embodiment, the present invention comprises 1.25% albuterol base (equivalent to 1.5% albuterol sulfate. In yet another alternative embodiment of the present invention a therapeutically effective amount of albuterol may include from about 0.025% to about 0.17% by weight albuterol sulfate, including the following intermediate ranges: about 0.025 wt % to about 0.029 wt %; about 0.030 wt % to about 0.039 wt %; about 0.040 wt % to about 0.049 wt %; about 0.050 wt % to about 0.059 wt %; about 0.060 wt % to about 0.069 wt %; about 0.070 wt % to about 0.079 wt %; about 0.080 wt % to about 0.089 wt %; about 0.090 wt % to about 0.099 wt %; about 0.10 wt % to about 0.17 wt %. In another alternative embodiment of the present invention, a therapeutically effective amount of ipratropium bromide may include from about 0.01 mg to about 1.0 mg of ipratropium bromide. Such therapeutically effective amount may also include the following intermediate ranges of ipratropium bromide: about 0.01 mg to about 0.02 mg; about 0.02 mg to about 0.04 mg; about 0.05 to about 0.07 mg; about 0.08 mg to about 0.10 mg; about 0.11 mg to about 0.13 mg; about 0.14 mg to about 0.16 mg; about 0.17 mg to about 0.19 mg; about 0.20 mg to about 0.22 mg; 0.23 mg to about 0.25 mg; 0.26 mg to about 0.28 mg; about 0.29 mg to about 0.31 mg; about 0.32 to about 0.34 mg; about 0.35 mg to about 0.37 mg; about 0.36 mg about 0.38 mg; about 0.39 mg to about 0.41 mg; about 0.42 mg to about 0.44 mg; about 0.45 mg to about 0.47 mg; about 0.48 mg to about 0.50 mg; about 0.51 mg to about 0.53 mg; about 0.54 mg to about 0.56 mg; about 0.57 mg to about 0.59 mg; about 0.60 mg to about 0.62 mg; about 0.63 mg to about 0.65 mg; about 0.66 mg to about 0.68 mg; about 0.69 mg to about 0.71 mg; about 0.72 mg to about 0.74 mg; about 0.75 mg to about 0.77 mg; about 0.79 mg to about 0.81 mg; about 0.82 mg to about 0.84 mg; about 0.85 mg to about 0.87 mg; about 0.88 mg to about 0.91 mg; about 0.92 mg to about 0.94 mg; about 0.95 mg to about 0.97 mg; about 0.98 mg to about 1.00 mg. In another alternative embodiment of the present invention, a therapeutically effective amount of ipratropium may include from about 0.001% to about 0.030% by weight ipratropium bromide, including the following intermediate ranges of ipratropium bromide: about 0.001 wt % to about 0.005 wt %; about 0.006 wt % to about 0.010 wt %; about 0.011 wt % to about 0.015 wt %; about 0.016 wt % to about 0.020 wt %; about 0.021 wt % to about 0.025 wt %; 0.026 wt % to about 0.030 wt %. Most pharmaceutical inhalation solutions contain the anti-microbial agent BAC. One problem with these solutions is that the BAC may cause paradoxic bronchoconstriction if the solution is administered repeatedly over short intervals. Another problem is that, when inhaled by patients, the BAC can cause dose-dependent bronchoconstriction. The inhalation solution of the present invention may be provided without BAC, thereby making it suitable, especially in an emergency situation, where the inhalation solution is administered repeatedly over a short period of time. Also, administering a BAC-free inhalation solution to a patient reduces the concomitant liability of adverse effects associated with BAC. It also reduces the toxicity and other side effects associated with BAC. The inhalation solution of the present invention may also be provided in sterile, unit dose treatments, thus eliminating the need to include BAC in the solution. Moreover, as shown in Table 1, in its sterile form the formulation of the present invention (which comprises a therapeutically effective amount of albuterol sulfate and ipratropium bromide) provides a stable inhalation solution such that the formulation can be stored (e.g., on a shelf) for long periods of time. TABLE 1 Stability Data 0.083 wt % Albuterol Sulfate and 0.017 wt % Ipratropium Bromide Assay* Albuterol Ipratropium Osmolality sulfate bromide pH (mOsm/kg) Time zero 98 98 3.3 283 25° C./35% RH 12 months 105 99 3.4 285 24 months 102 101 3.5 282 40° C./15% RH 3 months 100 99 3.5 284 6 months 103 102 3.4 283 *as percent of label claim (0.083 wt % albuterol sulfate and 0.017 wt % ipratropium bromide) As stated, the compositions provided herein are stable. For example, the compositions provided herein are stored between about 15° C. and about 30° C., and remain stable for a relatively long period of time. In one embodiment, the compositions are stored at 25° C. In another embodiment, the stability of the compositions provided herein may contain greater than 80%, 85%, 90% or 95% of the initial amount of active ingredient, e.g., Albuterol and Ipratropium at a given temperature for a long period of time. Thus, for example, a composition that is stable for 30 days at 25° C. would have greater than 80%, 85%, 90% or 95% of the initial amount of active ingredients present in the composition at 30 days following storage at 25° C. In another embodiment, the compositions herein are stable during long term storage, in that the compositions are suitable for administration to a subject in need thereof when they have been stored for a length of time (i.e., shelf-life) for a period greater than 1, 2 or 3 years at 25° C. In other embodiments herein, using Arrhenius Kinetics, >80% or >85% or >90% or >95% estimated bronchodilating agent remains after such storage, for example. Other indications of the stability of the present compositions can be shown in terms of by-products or degradation products present over time, as shown in Tables 2 and 3 below. TABLE 2 Albuterol degradation products/related Range at 6 to compounds as % of 24 months at Range in drug albuterol 25° C. substance 1 5-2-((1,1-Dimethyl- ND-0.012% ethyl)amino-1-hy- w/w droxyethyl)-2- hydroxybenzaldehyde 2 Bis-(2-hydroxy0-5- 0.09-0.174% (2-tertbutylamino- w/w 1-hydroxyethyl)phenyl- methyl ether 3 2-tert-butylamino-1- 0.01-0.12% (4-hydroxy-3-methoxy- w/w methylphenyl)-ethanol 4 Tert-butylamino-3- ND-0.0002% chloro-4-hydroxy- w/w 5-hydroxymethyl- acetophenone 5 Tert-butylamino-4- ND-0.002% hydroxy-5-hydroxy- w/w methylacetophenone 6 1-(4-hydroxy-3- 0.0009-0.036% methylphenyl)-2- w/w (tert-butylamino) ethanol 7 1-(5-chloro-4- ND hydroxy-3-hydroxy- methylphenyl)-2- (tert-butylamino) ethanol 8 Unknown 1 ND-0.07% by peak area 9 Any other unknown ND-0.025% by peak area 10 Total 0.18-0.23% ND = none detected TABLE 3 Ipratropium degradation Range at up products/related compounds to 24 months Range in drug as % of ipratropium bromide at 25° C. substance 1 Tropic acid ND-0.08% w/w 2 8S-ipratropium bromide ND-0.058% w/w 3 N-isopropyl-noratropine ND 4 Ipratropium alcohol ND-0.038% w/w 5 Any other unknown ND 6 Atropic acid ND 7 Total (excluding ND-0.2% APO-ipratropium) ND = none detected In one embodiment, the compositions herein are at least substantially clear, based on color measurement tests set forth by the America Public Health Association (“APHA”). In another embodiment of the present invention, the APHA color results for compositions herein at up to 24 months at 25° C. ranged from 0 to 5 units (mostly 0 units), as based on APHA standards. In one embodiment, the process of the present invention provides compositions having an albuterol content of about 2.5 mg to about 2.75 mg per vial. In another alternative embodiment, the process of the present invention provides compositions having an Ipratropium content of about 0.45-0.55 mg per vial. In yet another alternative embodiment, the process of the present invention provides an average fill volume of about 2.84 to about 3.30 ml into each vial. In another alternative embodiment, the compositions of the present invention may contain minimal amounts of contaminants including, but not limited to the following: TABLE 4 1. Volatiles Acetone about NMT 0.2 Φg/ml or less ethyl acetate about NMT 0.3 Φg/ml or less n-heptane NMT 0.1 Φg/ml or less n-propylacetate NMT 0.3 Φg/ml or less Toluene NMT 0.3 Φg/ml or less 2-butanone none detected (signal/nose NMT 3) Unknowns 2. Leachables Irganox 129 none detect (NMT 0.02 Φg/ml) Extractable 1 none detected (signal/noise NMT 3) Extractable 2 none detected (signal/noise NMT 3) Unknowns none detected (signal/noise NMT 3) In another alternative embodiment, compositions of the present invention may contain minimal amounts of particulate matter, including, but not limited to the following: NMT about 1000 to 5000, preferably about 3800 particles/vial >2Φm; NMT about 10 to 100, preferably about 80 particles/vial >10Φm; or NMT about 1 to 5, preferably about 3 particles/vial >25Φm. In another embodiment of the present invention, the inhalation solution may have a pH of about 2.0 to about 8.0. In another embodiment of the claimed invention, the solution may have a pH of about 3.0 to about 4.0, preferably a pH of about 3.5. The pH may be adjusted with 1N hydrochloric acid or 1N sulfuric acid. The inhalation solution of the present invention may also contain sodium citrate at a concentration of about 0.1 to 0.5% (w/w), preferably about 0.2% (w/w/) to control pH or may further contain a buffer. General and biological buffers in the pH range of about 2.0-8.0 include but are not limited to the following: acetate, barbital, borate, Britton-Robinson, cacodylate, citrate, collidine, formate, maleate, McIlvaine, phosphate, Prideaux-Ward, succinate, citrate-phosphate-borate (Teorell-Stanhagen), veronal acetate, MES, BIS-TRIS, ADA, ACES, PIPES, MOPSO, BIS-TRIS PROPANE, BES, MOPS, TES, HEPES, DIPSO, MOBS, TAPSO, TRIZMA, HEPPSO, POPSO, TEA, EPPS, TRICINE, GLY-GLY, BICINE, HEPBS, TAPS, and AMPD buffers. In another embodiment of the present invention, the osmolality of the inhalation solution may be adjusted from about 150 to about 550 mOsm/kg. In other embodiments of the present invention, the osmolality of the solution may be from about 275 to about 325 mOsm/kg. In yet another embodiment, the composition may have an osmolality of about 290 mOsm/kg. Tonicity adjusting agents include but are not limited to the following excipients: ammonium carbonate, ammonium chloride, ammonium lactate, ammonium nitrate, ammonium phosphate, amonium sulfate, ascorbic acid, bismuth sodium tartrate, boric acid, calcium chloride, calcium disodium edetate, calcium gluconate, calcium lactate, citric acid, dextrose, diethanolamine, dimethyl sulfoxide, edetate disodium, edetate trisodium monohydrate, fluorescein sodium, fructose, galactose, glycerin, lactic acid, lactose, magnesium chloride, magnesium sulfate, manitol, polyethyne glycol, potassium acetate, potassium chlorate, potassium chloride, potassium iodide, potassium nitrate, potassium phosphate, potassium sulfate, propylene glycol, silver nitrate, sodium acetate, sodium bicarbonate, sodium biphosphate, sodium bisulfite, sodium borate, sodium bromide, sodium cacodylate, sodium carbonate, sodium chloride, sodium citrate, sodium iodide, sodium lactate, sodium metabisulfite, sodium nitrate, sodium nitrite, sodium phosphate, sodium propionate, sodium succinate, sodium sulfate, sodium sulfite, sodium tartrate, sodium thiosulfate, sorbitol, sucrose, tartaric acid, triethanolamine, urea, urethan, uridine, and zinc sulfate. In one embodiment, the inhalation solution of the present invention is sterile. A benefit of a sterile inhalation solution is that it reduces the possibility of introducing contaminants into the patient when administered, thereby reducing the chance of an opportunistic infection in the patient. Non-adherence to COPD medication therapy and medication error are considerable problems. These problems can be significantly reduced by providing COPD patients a prepackaged, premixed, premeasured amount of albuterol and ipratropium. Providing these compounds in this fashion makes COPD therapy simple because it increases convenience and eliminates confusion in preparing appropriate dosages. These advantages are especially significant where treatments often come in multiple dosage units and must be diluted to specific concentrations suitable for treating patients. As discussed previously, this poses several problems. The present invention overcomes the aforementioned problems by providing therapeutically effective amounts of both albuterol and ipratropium in prepackaged, premixed, premeasured and/or unit dose amounts. In one embodiment, the present invention comprises one or more prefilled containers. The one or more containers each comprising a single unit dose of an aqueous solution comprising a therapeutically effective amount of albuterol and ipratropium for the treatment of COPD. Providing the inhalation solution in such a manner eliminates the need to dilute or mix COPD medications to obtain proper dosages for treatment. Also, no special pharmacy compounding is required, thereby reducing the chance of medication errors. Further, there is a lower risk of cross-contamination, and less waste of medication when providing an inhalation solution in a premixed, ready to use form. Other features of the present invention include improved user compliance and quality of life as compared to conventional treatments for COPD. While the level of compliance of any COPD treatment depends in part on the motivation of the user and the skill of the individual dispensing the treatment, compliance nevertheless may be improved by controlling factors such as the ease with which the treatment may be administered, as well as the desirability of receiving the treatment. The present invention provides a convenient, fast and reliable treatment for COPD and clearly represents an improvement over traditional COPD treatments. Also, the present invention is designed to facilitate user compliance by providing one or more dispensing containers comprising a premixed, premeasured inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium for the treatment of COPD. Such containers may be utilized in a method of treating COPD or the containers may be incorporated in a system and/or kit for treating the same. In one alternative embodiment, the present invention is a sterile, premixed, premeasured, BAC-free inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium in a single container. Each unit dose container comprises 3.0 mg/3 ml of albuterol sulfate (equivalent to 2.5 mg of albuterol) and 0.5 mg ipratropium bromide in a sterile, aqueous solution. Sodium chloride may be added to make the solution isotonic and hydrochloric acid may be added to adjust pH of the solution to about 4.0. The inhalation solution of the present invention may or may not include a chelating agent, such as EDTA. In another alternative embodiment, the inhalation solution of the present invention may be supplied as a 3 ml, sterile, BAC-free, nebulizer solution comprising from about 0.20 to about 0.5 mg ipratropium bromide and from about 0.75 mg/3 ml to about 3.0 mg/3 ml of albuterol sulfate. The nebulizer solution is contained in a unit-dose, low-density polyethylene (LDPE) container. Each unit-dose container may be disposed in a foil pouch, and each foil pouch may contain 5 or more unit-dose containers. Each foil pouch containing the unit dose container may be disposed in a shelf carton. The present invention provides an albuterol and ipratropium inhalation solution for treating different stages of COPD, including but not limited to, stages 0 to III. Some characteristics associated with the different stages of COPD are shown in Table 2. The information in this table is presented for illustrative purposes only. It is not intended to limit the scope of the invention. TABLE 2 Stage Severity Description 0 At risk Normal spirometry Chronic symptoms (cough, sputum production) I Mild FEV1/FVC < 70% FEV1 > 80% predicted With or without chronic symptoms II Moderate FEV1/FVC < 70% 30% ≧ FEV1 < 80% predicted (IIA: 50% ≧ FEV1 < 80%) (IIB: 30% ≧ FEV1 < 50%) With or without chronic symptoms III Severe FEV1/FVC < 70% FEV1 < 30% predicted or less than 50% predicted with respiratory failure or clinical signs of right heart failure. In the present invention, a therapeutically effective amount of albuterol and ipratropium is administered to induce bronchodilation and/or provide relief of bronchospasm associated with COPD. Such amount of albuterol and ipratropium may be administered to a patient after the onset of bronchospasm to reduce breathing difficulties resulting from COPD. In another embodiment, the albuterol and ipratropium may be administered prophylactically, that is, to prevent COPD progression. The quantity of albuterol and ipratropium to be administered will be determined on an individual basis, and will be based at least in part on consideration of the patient's size, the severity of the symptoms to be treated, and the results sought. The actual dosage (quantity of albuterol and ipratropium administered at a time) and the number of administrations per day will depend on the mode of administration, such as inhaler, nebulizer or oral administration. For example, about 2.5 mg of albuterol and about 0.5 mg of ipratropium bromide administered by nebulization 4 times per day with up to 2 additional 3 ml doses allowed per day, if needed, would be adequate to produce the desired bronchodilation effect in most patients. Further, the albuterol and ipratropium inhalation solution of the present invention may be administered together with one or more other drugs. For example, an antiasthmatic drug such as theophylline or terbutaline, or an antihistamine or analgesic such as aspirin, acetaminophen or ibuprofen, may be administered with or in dose temporal proximity to administration of a therapeutically effective amount of albuterol. The present invention and the one or more drugs may be administered in one formulation or as two separate entities. According to the present invention, a therapeutically effective amount of albuterol and ipratropium, alone or in combination with another drug(s), may be administered to a individual periodically as necessary to reduce symptoms of COPD. In another alternative embodiment, the inhalation solution of the present invention may be administered by nebulizer. Such nebulizer including, but not limited to, a jet nebulizer, ultrasonic nebulizer and breath actuated nebulizer. Preferably, the nebulizer is a jet nebulizer connected to an air compressor with adequate airflow. The nebulizer being equipped with a mouthpiece or suitable face mask. Specifically, a Pari-LC-Plus™ nebulizer (with face mask or mouthpiece) connected to a PRONEB™ compressor may be used to deliver the inhalation solution of the present invention to a patient. In an embodiment, the inhalation solution may be administered by nebulizers manufactured, designed or sold by Omron, such as the Omron Micro Air™ Ultrasonic Nebulizer. Other nebulizers may also include those manufactured, designed, or sold by Aerogen. In an alternative embodiment, the system and/or kit of the present invention comprises an inhalation solution comprising a therapeutically effective amount of albuterol and ipratropium in a prepackaged, premeasured, premixed and/or single unit dose form for the treatment of COPD. The inhalation solution may be sterile and/or BAC-free. In another embodiment, the present invention provides a system and/or kit for organizing and storing one or more prefilled dispensing containers, each container comprising a premixed, premeasured inhalation solution. The inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium. Such system and/or kit may provide such containers in prepackaged form. The one or more containers may be comprised of plastic including, but not limited to, a semi-permeable plastic such as LDPE. The container may also comprise a Twist-Flex™ top, such top comprising an easy-to-grip tab-like handle such that the container may be opened, for example, by twisting off the tab by hand. The Twist-Flex™ top is advantageous in that it allows for easy dispensing of the solution, prevents spillage and eliminates the need to open the container or tearing by cutting or tearing off the top, or the like, thereby reducing cross-contamination. In one alternative embodiment, the design of the container substantially conforms to those designs illustrated in U.S. Pat. Des. Nos. 317,715; 296,869; 289,609; or 275,732, which are incorporated herein by reference. One or more of the semi-permeable single unit dose containers may be prepackaged in aluminum foil pouch, such that the foil provides a protective barrier against environmental contaminants and light. Such a barrier improves the shelf-life and stability of the inhalation solution. In another alternative embodiment, the present invention comprises a prepackaged inhalation system and/or kit suitable for patients suffering from COPD. Such prepackaged system and/or kit comprising: (a) one or more single unit dosages of a therapeutically effective amount of albuterol and ipratropium; (b) administration instructions for the use of said unit dose as a treatment for COPD; and (c) a dispensing container prefilled with the one or more unit doses of albuterol and ipratropium. In another alternative embodiment, the prepackaged inhalation system and/or kit of the present invention provides one or more premixed, premeasured single unit dose vials comprising a therapeutically effective amount of albuterol and ipratropium for the treatment of bronchospasm associated with COPD, and instructions for using the same. In one alternative embodiment, the present invention is directed to a system for reducing medication error and enhancing therapeutic compliance of an individual suffering from chronic obstructive pulmonary disease, the prepackaged therapeutic system comprising: (a) one or more dispensing containers; the one or more containers each prefilled with about 0.1 ml to about 2.0 ml or 3 ml of a sterile, benzlakonium chloride-free, premixed, premeasured aqueous inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide; wherein the dosage of albuterol is about 2.5 mg and the dosage of ipratropium bromide is about 0.5 mg; the inhalation solution in each of the one or more containers is suitable for nebulization in a nebulizer; the inhalation solution in each of the one or more containers has a long shelf life; (b) one or more labels with indicia thereon, the indicia comprising efficacy dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one or more containers; (c) wherein the contraindication data comprises data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to atropine and derivatives thereof; and (d) wherein the adverse reaction data comprises data indicating that precipitation or worsening of narrow-angle glaucoma, acute eye pain, blurred vision, paradoxical bronchospasm, wheezing, exacerbation of chronic obstructive pulmonary disease symptoms, drowsiness, aching, flushing, upper respiratory tract infection, palpitations, taste perversion, elevated heart rate, sinusitis, back pain and sore throat may occur after administrating the inhalation solution in the one or more containers. The dosage and administration data may comprise data indicating that the recommended dose of the inhalation solution in each of the one or more containers is about 2.5 mg of albuterol and about 0.5 mg impratropium bromide in 3 ml of an aqueous solution administered 4 times per day by nebulization with up to 2 additional recommended doses allowed per day, if needed. Also, the adverse reaction data may comprise data indicating that immediate hypersensitivity reactions to the inhalation solution in each of the one or more containers may occur after administration of the inhalation solution, said hypersensitivity reactions comprising urticaris, angioedema, rash, pruritis, oropharyngeal, edema, bronchospasm, and anaphylaxis. The adverse reaction data may also comprise data indicating that allergic-type reactions may occur after administrating the inhalation solution in the one or more containers, including skin rash, prurities, and urticaria. The adverse reaction data may further comprise data indicating a list of one or more adverse events that may occur after administrating the inhalation solution, said adverse events including chest pain, diarrhea, dyspepsia, nausea, leg cramps, bronchitis, lung disease, pharyngitis, pneumonia, and urinary tract infection. In another alternative embodiment, the present prepackaged therapeutic system and/or kit for treating bronchospasm in a patient suffering from chronic obstructive pulmonary disease may comprise. (a) one or more dispensing containers; the one more containers each prefilled with 3 ml of a sterile, stable, premixed, premeasured aqueous inhalation solution free of benzalkonium chloride; the inhalation solution consisting of sodium chloride, water, edetate disodium, an acid to adjust the pH of the inhalation solution to about 4, and a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide, wherein the amount of albuterol is about 2.50 mg and the amount of ipratropium bromide is about 0.5 mg; the inhalation solution in each of the one or more containers is suitable for nebulization in a nebulizer; said inhalation solution having a long shelf life; (b) one or more labels with indicia thereon; the indicia comprising efficacy, dosage, administration, contraindication and adverse reaction information pertaining to the inhalation solution in each of the one or more containers; (c) wherein the dosage and administration data comprises data indicating that the recommended dose of the inhalation solution in each of the one or more containers is about 2.5 mg of albuterol and about 0.5 mg impratropium bromide in 3 ml of an aqueous solution administered 4 times per day by nebulization with up to 2 additional recommended doses allowed per day, if needed; (d) wherein the contraindication data comprises data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to atropine and derivatives thereof; (e) wherein the adverse reaction data comprises data indicating that immediate hypersensitivity reactions to the inhalation solution in each of the one or more containers may occur after administrating the inhalation solution, said hypersensitivity reaction including urticaris, angioedema, rash, pruritis, oropharyngeal, edema, bronchospasm, and anaphylaxis; (f) wherein the adverse reaction data comprises data indicating that allergic-type reactions may occur after administrating the inhalation solution in the one or more containers; said allergic type reaction, including skin rash, prurities, and urticaria; (g) wherein the adverse reaction data comprises data indicating that precipitation or worsening of narrow-angle glaucoma, acute eye pain, blurred vision, paradoxical bronchospasm, wheezing, exacerbation of chronic obstructive pulmonary disease symptoms, drowsiness, aching, flushing, upper respiratory tract infection, palpitations, taste perversion, elevated heart rate, sinusitis, back pain and sore throat may occur after administrating the inhalation solution in the one or more containers; and (h) the adverse reaction data includes a list of one or more adverse events that may occur after administration of the inhalation solution in each of the one or more containers; the adverse events including chest pain, diarrhea, dyspepsia, nausea, leg cramps, bronchitis, lung disease, pharyngitis, pneumonia, and urinary tract infection. The prepackaged inhalation system and/or kit may be provided in one of any number of forms, including, but not limited to, a box containing one or more prepackaged, unit dose vials or a box containing individual packages or pouches comprising one or more unit dose vials. For example, an embodiment of a unified prepackaged system and/or kit for treating COPD in patients is depicted in FIG. 5. Specifically, FIG. 5 depicts support package (10). Support package (10) may include, but is not limited to, a box, carton or any other enclosed container. The support package comprising one or more prepackaged, pre-filled dispensing containers (21-25). Each container comprising a premixed, premeasured inhalation solution. The inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium for treating COPD. The inhalation solution may be provided in sterile and/or BAC-free form. Support package (10) may also incorporate one or more labels (13) therein. One or more labels (13) may comprise indicia (14) indicating that the inhalation solution can be used to relieve symptoms associated with COPD, such as bronchospasm. The label may also comprise indicia (15) which provides instructions for using the inhalation solution to relieve such symptoms. As used herein “indicia” includes, but is not limited to, wording, pictures, drawings, symbols and/or shapes. A non-limiting example of the indicia that may appear on the one or more labels (13) is shown in FIG. 7. The one or more labels may be positioned on one or more surfaces of support package (10) or a separate sheet, or any combination thereof. Support package (10) may also incorporate lid (16) to enclose the packaging material therein. The system and/or kit of the present invention may also include a label and/or instructions designed to facilitate user compliance. For example, in an embodiment, a system and/or kit of the present invention comprises packaging material containing one or more prepackaged vials comprising a sterile, premixed, premeasured unit dose of an inhalation solution comprising a therapeutic effective amount of albuterol and ipratropium. The packaging material may further comprise a label indicating that each vial can be used with a nebulizer for the relief of symptoms associated with COPD, such as bronchospasm. Such instructions may also include instructions on dosage for each nebulizer treatment, as well as instructions for administration, such as by nebulizer. The instructions may be positioned on one or more surfaces of the packaging material therein, or the instructions may be provided on a separate sheet, or any combination thereof. The present invention is also directed to a method of treating symptoms associated with COPD, including bronchospasm, wherein a therapeutically effective amount of albuterol and ipratropium may be administered as a unit dose. Such unit dose may be in the form of a nebulizer solution. In another embodiment, the present invention is directed to a method for inducing bronchodilation or providing relief of bronchospasm in a patient suffering from chronic obstructive pulmonary disease, said method comprising the step of: (a) providing the patient a prepackaged therapeutic system comprising: one or more dispensing containers; the one or more containers each prefilled with about 3 ml of a sterile, benzalkonium chloride-free, premixed, premeasured aqueous inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide; wherein the amount of albuterol is about 2.5 mg and the amount of ipratropium bromide is about 0.5 mg; the inhalation solution in each of the one or more containers is suitable for nebulization in a nebulizer; the inhalation solution in each of the one or more containers has a long shelf life; (b) providing the patient or prescriber of the prepackaged therapeutic system dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one or more containers; (c) wherein the contraindication data comprises data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to atropine and derivatives thereof; and (d) wherein the adverse reaction data comprises data indicating that precipitation or worsening of narrow-angle glaucoma, acute eye pain, blurred vision, paradoxical bronchospasm, wheezing, exacerbation of chronic obstructive pulmonary disease symptoms, drowsiness, aching, flushing, upper respiratory tract infection, palpitations, taste perversion, elevated heart rate, sinusitis, back pain and sore throat may occur after administrating the inhalation solution in the one or more containers. In the present method, the dosage and administration data may inform the patient or prescriber the recommended dose of the inhalation solution in each of the one or more containers is about 2.5 mg of albuterol and 0.5 mg impratropium bromide in 3 ml of an aqueous solution administered 4 times per day by nebulization with up to 2 additional recommended doses allowed per day, if needed. The adverse reaction may also inform the patient or prescriber that immediate hypersensitivity reactions to the inhalation solution in each of the one or more containers may occur after administration of the inhalation solution, said hypersensitivity reactions including urticaris, angioedema, rash, pruritis, oropharyngeal, edema, bronchospasm, and anaphylaxis. The adverse reaction data may further inform the patient or prescriber that allergic-type reactions may occur after administrating the inhalation solution in the one or more containers, including skin rash, prurities, and urticaria. Also, the adverse reaction data may include a preprinted list of one or more adverse events that may occur after administrating the inhalation solution, said adverse events comprising chest pain, diarrhea, dyspepsia, nausea, leg cramps, bronchitis, lung disease, pharyngitis, pneumonia, and urinary tract infection. In another alternative embodiment, the present invention is directed to a method for inducing bronchodilation or providing relief of bronchospasm in a patient suffering from chronic obstructive pulmonary disease, said method comprising the step of: (a) providing a patient the prepackaged therapeutic system comprising: one or more dispensing containers; the one more containers each prefilled with about 3 ml of a sterile, stable, premixed, premeasured aqueous inhalation solution free of benzalkonium chloride; the inhalation solution consisting of water, edetate disodium, sodium chloride, and an acid to adjust the pH of the inhalation solution to about 4, and a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide, wherein the amount of albuterol is about 2.50 mg/3 ml and the amount of ipratropium bromide is about 0.5 mg/3 ml; the inhalation solution in each of the one or more containers is suitable for nebulization in a nebulizer; (b) providing the patient or prescriber the prepackaged therapeutic system efficacy, dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one or more containers; (c) wherein the dosage and administration data informs the patient or prescriber that the recommended dose of the inhalation solution in each of the one or more containers is about 2.5 mg of albuterol and 0.5 mg impratropium bromide in 3 ml of an aqueous solution administered 4 times per day by nebulization with up to 2 additional recommended doses allowed per day, if needed; (d) wherein the contraindication data comprises information indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to atropine and derivatives thereof; (e) wherein the adverse reaction data informs the patient or prescriber that immediate hypersensitivity reactions to the inhalation solution in each of the one or more containers may occur after administrating the inhalation solution in the one or more containers, said hypersensitivity reaction including urticaris, angioedema, rash, pruritis, oropharyngeal, edema, bronchospasm, and anaphylaxis; (f) wherein the adverse reaction data informs the patient or prescriber that possible allergic-type reactions may occur after administering the inhalation solution in the one or more containers, including skin rash, prurities, and urticaria; (g) wherein the adverse reaction data informs the patient or prescriber that precipitation or worsening of narrow-angle glaucoma, acute eye pain, blurred vision, paradoxical bronchospasm, wheezing, exacerbation of chronic obstructive pulmonary disease symptoms, drowsiness, aching, flushing, upper respiratory tract infection, palpitations, taste perversion, elevated heart rate, sinusitis, back pain and sore throat may occur after administrating the inhalation solution in the one or more containers; and (h) the adverse reaction data includes a preprinted list of one or more adverse events that may occur after administration of the inhalation solution in each of the one or more containers; the adverse events comprising chest pain, diarrhea, dyspepsia, nausea, leg cramps, bronchitis, lung disease, pharyngitis, pneumonia, and urinary tract infection. In an alternative embodiment, the method of the present invention comprises the step of administering to a patient a therapeutically effective amount of albuterol and ipratropium. Such solution may also be prepackaged, premixed, premeasured, BAC-free and/or sterile. Such solution may also be in a single unit dose vial. In another alternative embodiment, the method of the present invention comprises the step of administering to a patient in need an inhalation solution comprising a therapeutically effective amount of albuterol and ipratropium. The inhalation solution being administered by nebulizer, more preferably a jet nebulizer connected to an air compressor with adequate air flow. In yet another alternative embodiment, in reference to FIGS. 1-4, the method of the present invention comprises the steps: (i) placing an inhalation solution comprising a therapeutically effective amount of albuterol and ipratropium (1) into a nebulizer cup (2). The nebulizer may be powered by attachment to compressed gas cylinders or an electrically driven compressor; (ii) using a “T” adapter (3) to fit the nebulizer cup lid (4) to a mouthpiece (5) or facemask (6); (iii) drawing the inhalation solution (1) up by the velocity of a gas jet and fragmenting it into an aerosol; (iv) passing the aerosol through the mouthpiece (5) or facemask (6) to the patient (7) afflicted with bronchospasm; and (v) the patient continues breathing until no more mist is formed in the nebulizer chamber (8). This may occur in about 5-15 minutes. In one alternative embodiment, the usual starting dosage for patients may be about 2.50 mg albuterol and 0.5 mg ipratropium administered 3 or 4 times daily, as needed by nebulization. To administer these amounts of albuterol and ipratropium, the entire contents of one unit dose vial (e.g., about 3.0 mg/3 ml albuterol sulfate and 0.5 mg/3 ml ipratropium bromide) may be used. Preferably, the nebulizer flow rate is adjusted to deliver the albuterol and ipratropium over 5 to 15 minutes. Further, in an alternative embodiment, the method of the present invention comprises the steps: (i) preparing an inhalation solution comprising a therapeutically effective amount of albuterol and ipratropium by diluting one or more solutions comprising the ipratropium or albuterol; and (ii) administering the inhalation solution to a patient in need thereof. The present invention also provides a process for making a prepackaged, sterile, premixed, premeasured, and/or BAC-free inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium. In such an embodiment, the method of the present invention comprises one or more of the following steps: (i) adding at least a therapeutically effective amount of albuterol and ipratropium in a carrier, such as water; (ii) sterilizing the solution and sealing the container. An osmotic adjusting agent may be added to adjust the isotonicity of the solution. Preferably, the solution of the present invention is isotonic, and an osmotic adjusting agent may be added to adjust the isotonicity of the solution to about 280 to about 320 mOsm/kg. Additionally, an acid (e.g., hydrochloride) may be added to adjust the pH of the solution to a level of about 3.0 to about 5.0, preferably about 4.0. In another embodiment, a process for making an inhalation solution of the present invention comprises one or more of the following steps: (i) adding at least a therapeutically effective amount of albuterol and ipratropium in a carrier such as water; (ii) placing the mixture in a container, and sterilizing the mixture by steam sterilization, or any other sterilizing means known in the art. Each albuterol and ipratropium mixture being filled into a vial, and then packaged, stored and/or used directly. Here, the resulting mixture is stable, and after sterilization, it can be dispersed, if necessary, into multiple mixtures each containing a unit dose of a therapeutically effective amount of albuterol and ipratropium. Osmotic adjusting agents that may be used include, but are not limited to, sodium chloride, potassium chloride, zinc chloride, calcium chloride and mixtures thereof. Other osmotic adjusting agents may also include, but are not limited to, mannitol, glycerol, and dextrose and mixtures thereof. In an alternative embodiment, the present invention may comprise about 0.4 to about 1.0 weight percent ionic salt. Preferably, the present invention comprises 0.9 wt % of an osmotic adjusting agent. In an alternative embodiment, the inhalation solution of the present invention may be prepared as follows: (i) fitting a stainless steel formulation tank with a bottom drain and a tri-blender for mixing; (ii) filling the tank with approximately 95% of the required amount of Purified Water USP at a temperature of between 18° C. to 25° C.; while mixing, (iii) adding EDTA USP, hydrochloric acid, and at least a therapeutically effective amount of Albuterol Sulfate USP and Ipratropium Bromide to the tank; (iv) continue mixing until all chemical components are dissolved; (v) adding Purified Water USP to adjust the final volume, if necessary, thus producing an albuterol and ipratropium bromide mixture. From the formulation tank, the albuterol and ipratropium mixture may be pumped through sanitary delivery lines directly into a form-fill-seal (FFS) machine. The albuterol and ipratropium mixture may pass through a 0.2 micron sterilizing cartridge filter, then into a reservoir tank, through a second 0.2 micron sterilizing cartridge filter to the filling nozzles within the sterile air shower compartment, and subsequently into formed vials of low density polyethylene (LDPE). The albuterol and ipratropium mixture may be sterile filled into the vials such that each vial contains a single unit dose of a therapeutically effective amount of albuterol. The filled vials may then be sealed. The FFS machine may form, fill and seal the vials in a continuous operation under aseptic conditions, thus producing a sterile product. For example, cards of five filled vials (FIG. 6) may be overwrapped into a protective laminated foil pouch using an autowrapper machine. Six to twelve such pouches may then be packaged in a shelf carton, thus forming a prepackaged therapeutic system for treating COPD in patients. An appropriate label and instructions may be added in the shelf carton. The present invention is also directed to a method of forming a unit-dose nebulizer solution comprising the step of: (i) preparing a mixture containing a therapeutically effective amount of albuterol and ipratropium bromide in a pharmaceutically acceptable carrier. Said mixture being suitable for nebulization in a nebulizer. Additionally, the present invention is directed to a method of making a prepackaged, stable, premeasured, and/or premixed aqueous nebulizer solution for reducing medication error and enhancing therapeutic compliance of an individual suffering from chronic obstructive pulmonary disease. In one embodiment, the method may comprise the steps of adding water, albuterol sulfate and ipratropium bromide into a container at a temperature between about 2° C. and about 70° C., or about 2° C. and about 50° C., or about 2° C. and about 30° C., or about 2° C. and about 25° C., or about 5° C. and about 25° C., preferably about 18° C. and about 25° C. to form a solution, wherein the final concentration of the albuterol and ipratropium bromide in the solution ranges from about 0.06 wt. % to about 0.1 wt. % albuterol and about 0.03 wt. % to about 0.1 wt. % ipratropium. The present method may also comprise the step of adjusting the pH of said solution to about 3.0 to about 4.0, preferably 3.5. The method of the present invention may further comprise the step of adding hydrochloric acid to adjust the pH of the inhalation solution. The method of the present invention may further comprise adding sufficient osmotic adjusting agent to the solution so that the isotonicity of the solution is from about 280 mOsm/kg to about 320 mOsm/kg. The present method may further require filling the solution into one or more dispensing vials, each vial being filled with about 0.1 ml to about 5 ml, or about 0.1 ml to about 2.25 ml, or about 0.1 ml to about 3.0 ml, about 0.5 ml to about 3.0 ml, or about 0.5 ml to about 2.0 ml, or about 0.1 ml to about 2 ml, preferably about 0.5 ml to about 1 ml, about 2 ml, or about 3 ml of the solution such that the solution in the each vial comprises a unit dose of a therapeutically effective amount of albuterol and ipratropium bromide. Also, in another alternative embodiment, the stability of the solution in the one or more dispensing containers is such that the solution is therapeutically effective following storage for 12 months at 25° C. The solution may be suitable for nebulization in a nebulizer. The method may further comprise the step of sterile sealing the one or more vials after the solution is filled in the one or more vials. The method may further comprise the step of filing the nebulizer solution into the one or more low density polyethylene dispensing vials, wherein the solution filled in the one or more dispensing vials comprises about 0.4 wt. % to about 1.0 wt. % ionic salt, and the solution filled in the one or more dispensing vials comprises about 0.9% of an osmotic adjusting agent. The method further comprising the step of adding albuterol and ipratropium comprises adding sufficient albuterol and ipratropium so that the concentration of albuterol is about 0.083 wt. % and the concentration of ipratropium bromide is about 0.017 wt. % in the solution. Drugs administered by nebulization play a major role in the treatment of COPD. It has been shown that some patients have difficulty inhaling sufficient amounts of the prescribed medication from a nebulizer and this may be a reason for treatment failure. However, one of the drawbacks of nebulization therapy is the number of times it must be performed each day, and the amount of time each treatment takes. For example, an individual may be required to receive 4 doses of inhalation solution per day by nebulization. In some instances, each nebulizer treatment takes about 15 minutes, or more to deliver a 2.5 ml fill volume of a bronchodilator, though the amount of time may vary depending on the model of the nebulizer used. Thus, in one day, an individual may be required to spend an hour or more to receive the necessary dosage of albuterol and ipratropium to induce bronchodilation or obtain relief of bronchospasm associated with COPD, for example. The time requirements for nebulization therapy can be burdensome, and cause individuals to skip required dosages during the day. The impact of not following the prescribed dosage regimen could compromise the individual's condition. In one alternative embodiment, the volume of the albuterol/ipratropium inhalation solutions of the present invention is about 0.1 ml to about 2.25 ml, or about 0.1 ml to about 2 ml, or about 1 ml to about 2 ml, or about 1.5 ml to about 2 ml, preferably about 1 ml, about 1.5 ml, about 2.0 ml, or about 2.25 ml. In another alternative embodiment, the volume of the albuterol/ipratropium inhalation solution of the present invention is about 0.05 ml to about 1.0 ml; 0.1 ml to about 0.9 ml; 0.1 ml to about 0.8 ml; 0.1 ml to about 0.7 ml; 0.1 ml to about 0.6 ml; 0.1 ml to about 0.5 ml; 0.1 ml to about 0.4 ml; 0.1 ml to about 0.3 ml; 0.1 ml to about 2.0 ml. In one preferred embodiment the fill volume of the albuterol/ipratropium inhalation solution of the present invention is from about 0.05 ml to about 0.4 ml, preferably from about 0.1 ml to about 3.0 ml, more preferably about 0.25 ml. While no clinical trials or other experiments were carried out on these volumes, it is believed that such volumes would be more beneficial over conventional nebulizer solutions (e.g. 2.5 ml or 3.0 ml fill volume) because they will enable the individual to receive more medication (e.g., albuterol and ipratropium) in less time during each nebulization treatment. Also, it is believed that the fill volumes of the present invention will minimize common handling complications with nebulizer therapy, and it may extend the life of the nebulizer. In one alternative embodiment, the fill volumes of the present invention may reduce the time of each nebulization treatment by at least 20%, 30%, 40%, 50%, 60%, 70% or 80% or more over conventional nebulizer treatments (e.g. 2.5 ml or 3 ml fill volume). In another alternative embodiment, the fill volumes of the present invention may reduce each nebulization treatment to about or less than about 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 minutes, or any range therebetween less over conventional nebulizer treatments (e.g. 2.5 ml or 3.0 ml fill volume). Reducing the amount of time to complete the treatment means individuals will be more likely to comply with the prescribed dosing regimen and achieve optimal benefit from the medication prescribed. Another drawback of conventional nebulizer treatments is the loss of medication during administration. Conventional nebulizer solutions comprise about 2.5 ml fill volume of inhalation solution, or more. For example, when nebulizing an inhalation solution comprising 2.5 ml or more, about 0.7 ml of the solution remains in the nebulizer system after treatment, though the amount may vary depending on the model of the nebulizer used. In these instances, the individual is not receiving the prescribed dosage or optimum dosage of inhalation medication. For example, in one day, due to the residual medication remaining in the nebulizer system after each treatment, an individual fails to receive approximately 2.1 ml, or more of the prescribed daily amount of medication. It is believed that the fill volumes of the albuterol/ipratropium inhalation solutions of the present invention will result in lesser amounts of solution remaining in the nebulizer system after treatment, when compared to conventional inhalation solutions (e.g. 2.5 ml or 3 ml fill volume). Less solution remaining in the nebulizer system means more medication (e.g., albuterol and ipratropium) administered to the individual during each treatment. In one alternative embodiment, the amount of solution remaining in the nebulizer system after each treatment may be less than 0.50 ml, or less than 0.30 ml, or less than 0.20 ml or less than 0.10 ml or less than 0.05 ml of the albuterol/ipratropium inhalation solutions of the present invention, e.g. an inhalation solution comprising 2.5 mg albuterol and 0.5 mg ipratropium bromide. Important factors to effective nebulizer treatment is deep inspiration to ensure deep penetration of the medication into the lungs, and steady breath-holding to ensure good retention of the medication in the lungs. It is believed that administering a fill volume less than 2.0 ml, preferably from about 0.1 ml to about 0.3 ml, more preferably about 0.25 ml of an inhalation solution into a nebulizer, for example, will optimize the therapeutic effect of the individual's deep inspiration efforts during treatment, and will optimize the therapeutic effect of the individual's breath-holding efforts as well. This is due to the shorter treatment time and increased concentration of the albuterol and ipratropium in the solution. Accordingly, in one alternative embodiment, the present invention is a method of facilitating patient care, reducing medication error, reducing nebulizer treatment time, improving the efficiency and efficacy of nebulizing therapy or enhancing therapeutic compliance of an individual suffering from COPD. In one alternative embodiment, such method may comprise the step of placing about 0.1 ml to about 2.0 ml of the albuterol/ipratropium inhalation solutions of the present invention into a chamber of a nebulizer. The nebulizer having a mouthpiece or facemask associated with the chamber of the nebulizer. The mouthpiece or facemask is positioned in close proximity to the individual's mouth or face. The inhalation solution may be passed in a mist form from the nebulizer chamber through the mouthpiece or facemask to the individual while the individual breathes into the mouthpiece or facemask. The individual continues breathing into the mouthpiece or facemask until the nebulization treatment is finished. This may take about or less than about 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 or 0.5 minutes, or any range therebetween. In another alternative embodiment, the treatment may be finished in about 60, 50, 40, 30, 20, 10, 5 or 1 second, or any range therebetween. In an alternative embodiment, the nebulization treatment is finished when at least substantially all the mist is removed from the nebulizer chamber. This may take about or less than about 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 or 0.5 minutes, or any range therebetween. In an alternative embodiment, it may take about 60, 50, 40, 30, 20, 10, 5 or 1 second, or any range therebetween. In another alternative embodiment, the system of the present invention comprises one or more dispensing containers prefilled with about 0.1 ml to about 2.0 ml, or about 0.1 ml to about 1.0 ml; 0.1 ml to about 0.9 ml; 0.1 ml to about 0.8 ml; 0.1 ml to about 0.7 ml; 0.1 ml to about 0.6 ml; 0.1 ml to about 0.5 ml; 0.1 ml to about 0.4 ml; 0.1 ml to about 0.3 ml; 0.1 ml to about 2.0 ml; about 0.5 ml to about 2.0 ml, or about 0.1 ml to about 2.25 ml, or about 1.0 ml to about 2.0 ml, or about 2.0 ml to about 2.4 ml of a premixed, premeasured, aqueous inhalation solution comprising a single unit dose of a therapeutically effective amount of albuterol and ipratropium bromide. In one preferred embodiment, the present invention comprises 0.05 ml to about 0.4 ml, preferably from about 0.1 ml to about 0.3 ml, more preferably about 0.25 ml. The amount of albuterol may range from about 0.60 mg to about 5.0 mg, preferably about 2.5 mg. The amount of ipratropium bromide may range from about 0.01 mg to about 1.0 mg, preferably about 0.5 mg. In another alternative embodiment, the amount of albuterol may range from about 2.0 mg to about 3.0 mg, preferably about 2.5 mg. The solution may be suitable for nebulization in a nebulizer, and the solution may be stable, in that the inhalation solution is therapeutically effective following storage for 12 months at 25° C., for example. Also, in another embodiment, the inhalation solution in each of the one or more containers comprise a preservative or any other suitable anti-microbial agent, such as benzalkonium chloride, or may be preservative free. In one alternative embodiment, the inhalation solution may comprise 0.001% to about 2.0%, or 0.001% to about 0.5%, or about 0.01% to about 0.1% of a preservative, such as benzalkonium chloride, for example. The inhalation solution may further comprise sodium chloride, water, and an acid to adjust the pH of the inhalation solution to about 4, preferably about 3.5. The system may further comprise a label that indicates that the inhalation solution can be used to relieve bronchospasm associated with chronic obstructive pulmonary disease. In one alternative embodiment, the label may comprise indicia comprising efficacy, dosage, administration, contraindication and adverse reaction data pertaining to the inhalation solution in each of the one or more containers. The contraindication data may comprise data indicating that the inhalation solution in each of the one or more containers is contraindicated for humans with hypersensitivity to any of the ingredients contained in the inhalation solution. Also, the adverse reaction data may comprise data indicating that lung disease, bronchitis, diarrhea or phargaryngitis may occur after administration of the inhalation solution. The dosage and administration data may also comprise data indicating that the recommended dose of the inhalation solution in each of the one or more containers may be administered 1, 2, 3, 4, 5, 6, 7 or 8 times per day by nebulization. The present invention is also directed to a method of reducing medication error and enhancing therapeutic compliance of an individual suffering from chronic obstructive pulmonary disease. In one such embodiment, the method comprises the step of administrating to the individual at least one or more dispensing vials of the inhalation solution described herein, for example. Dispensing vials may include, but are not limited to, any container comprising glass, low density polyethylene, or any other material capable of preventing the solution from leaking out of the container. The vial may be enclosed by any conventional means, including but not limited to, screw cap, heat seal, snap-on top, flip-top, twist-off stopper, peel away top, and the like. In accordance with the present invention, the albuterol/ipratropium inhalation solution may be stored in or dispensed from any dispensing vial made of suitable plastic material. For example, the dispensing vial may be constructed of any suitable elastomeric material, such as olefin-based materials, including but not limited to, polyethylene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ethylene-acrylic ester copolymers, iononomers, and combinations thereof. Furthermore, polymers having barrier properties, such as polyvinylidene chloride and ethylene-vinyl alcohol copolymers, as well as polymers such as polyvinyl chloride, polyester, polyamide and polyurethanes may also be used. In an alternative embodiment, the present invention also comprises a device for use in the relief of symptoms associated with COPD, including bronchospasm. Such device may take the form of a label, written instructions or any other form incorporating indicia thereon. The device may comprise indicia that indicates that a patient suffering from symptoms associated with COPD can be treated with at least one prepackaged, sterile, premixed, premeasured and/or BAC-free inhalation solution comprising a unit dose of a therapeutically effective amount of albuterol and ipratropium in a single vial. The inhalation solution being suitable for nebulization in a nebulizer. The device may also comprise indicia that provides instructions for utilizing the inhalation solution to treat said symptoms in patients. EXAMPLES To evaluate the efficacy and safety of the inhalation solution of the present invention, a double-blind, randomized, positive control trial was performed. The design, results and conclusion of the study are described in detail below. Patients A total of 863 patients were initially randomized for enrollment in the trial. To be eligible for enrollment, patients had to meet the criteria described in Table 3. TABLE 3 Inclusion/Exclusion Criteria Design Element Description Inclusion Diagnosis with COPD with an FEV1 between 25% and 65% Criteria of the normal predicted value. Age > 40 years. Regular use of one or more bronchodilators for a minimum of 3 months prior to enrollment. History of at least 10 pack-years of smoking. Ability to refrain from the use of theophylline, salmeterol and oral β2 agonists for the duration of the trial (as judged by the investigator). Ability to safely complete a 6-minute walk. Willingness to provide informed consent. Exclusion Diagnosis of anthracosis, silicosis, any parenchymal Criteria disease not attributable to COPD, polycythemia, or pulmonale, hypoxia, or a primary diagnosis attributable to allergic rhinitis, atopy, or COPD. Clinically significant obstructive urinary disease, narrow-angle glaucoma, unstable angina pectoris or myocardial infarction in the past 6 months, known drug abuse within the last 12 months, or hospitalization for pulmonary exacerbation within the past 2 months. Known hypersensitivity to any component of the study medications. Investigational drug use within 30 days of first dose of study medication. Pregnancy or breastfeeding. Interventions The doses of each individual agent and the ipratropium and albuterol combination were as shown in Table 4 below. All study medications were administered 4 times per day (ideally every 6 hours) by inhalation using a Pari LC Plus™ nebulizer and Pari Proneb™ compressor. Concomitant use of bronchodilators was restricted during the trial. Oral and inhaled steroic use was permitted throughout the trial, provided that dosing remained constant. TABLE 4 Study Medication Albuterol (base) Ipratropium bromide Albuterol alone 2.5 mg/3 ml Ipratropium alone 0.5 mg/3 ml Albuterol and 2.5 mg/3 ml 0.5 mg/3 ml Ipratropium Combination Efficacy Results Of the 863 patients who were randomized and began treatment, 289 withdrew prematurely from the trial, including 28 patients who did not meet the inclusion/exclusion criteria and were inappropriately enrolled. A total of 663 patients received both the inhalation solution of the present invention and at least one other study medication and completed at least one post-dose measurement of FEV1. These subjects contributed to the 647 evaluable comparisons in each portion of the primary analysis, as the majority of patients completed treatment on all three study medications. The primary efficacy variable was the change from pre-dose to peak FEV1 measured within 3 hours after dosing during the crossover phase of the trial. As can be seen in Table 5, the mean increase in FEV1 was significantly higher for the albuterol and ipratropium combination than for either agent used alone. The improvement for the combination over albuterol alone was 23.6% and over ipratropium alone was 37.2%. The time course of FEV1 response is shown in Table 6. TABLE 5 Efficacy Results in Crossover Phase Combination vs. Albuterol Combination vs. Ipratropium Combination Albuterol Combination Ipratropium Parameter n mean mean p value n mean mean p value Peak FEV1 (liters) 647 0.387 0.313 <0.001 647 0.387 0.282 <0.001 During the parallel phase of the trial, separate groups of patients self-administered only one of the three study medications during the final 6 weeks of the trial. Results for the parallel phase yielded results essentially identical to the crossover phase. The albuterol and ipratropium combination maintained the same magnitude of superiority over each component medication alone that was observed during the crossover phase in peak FEV1 response. Safety/Tolerability Adverse reactions concerning the albuterol and ipratropium combination were evaluated from the clinical trials described above. Treatment-emergent adverse events that were reported by 1% or greater of patients are summarized by medication in Table 6. As can be seen, there were no differences between the albuterol and ipratropium combination and the individual medication in incidence of patients with adverse events across body systems. TABLE 6 Adverse Event Reports (ADVERSE EVENTS OCCURRING IN ≧1% OF TREATMENT GROUP(S) AND WHERE THE COMBINATION TREATMENT SHOWED THE HIGHEST PERCENTAGE) Albuterol and Ipratropium Body System Albuterol Ipratropium Combination COSTART Term n (%) n (%) n (%) NUMBER OF 761 754 765 PATIENTS N (%) Patients 327 (43.0) 329 (43.6) 367 (48.0) with A BODY AS A WHOLE Pain 8 (1.1) 4 (0.5) 10 (1.3) Pain chest 11 (1.4) 14 (1.9) 20 (2.6) DIGESTIVE Diarrhea 5 (0.7) 9 (1.2) 14 (1.8) Dyspepsia 7 (0.9) 8 (1.1) 10 (1.3) Nausea 7 (0.9) 6 (0.8) 11 (1.4) MUSCULO-SKELETAL Cramps leg 8 (1.1) 6 (0.8) 11 (1.4) RESPIRATORY Bronchitis 11 (1.4) 13 (1.7) 13 (1.7) Lung Disease 36 (4.7) 34 (4.5) 49 (6.4) Pharyngitis 27 (3.5) 27 (3.6) 34 (4.4) Pneumonia 7 (0.9) 8 (1.1) 10 (1.3) UROGENITAL Infection 3 (0.4) 9 (1.2) 12 (1.6) urinary tract Additional adverse reactions reported in more than 1% of patients treated with the albuterol and ipratropium combination included constipation and voice alterations. Example 2 Example 2 is a prophetic example of a nebulizable inhalation solution of the present invention having about 0.5 ml fill volume. It is provided to illustrate, but not limit, the present invention. It is believed that prophetic Example 2 would be suitable for inducing bronchodialation or providing relief of bronchospasm in an individual 2 to 12 years suffering from COPD. The inhalation solution may be a sterile, premixed, premeasured single unit dose. It may also comprise all other attributes, features and ingredients of the various embodiments of the present invention, as described herein. Prophetic Example 2 may be administered to an individual in accordance with one or more of the modes of administration described herein. TABLE 9 Ingredient Composition (% w/w) Range (% w/w) Albuterol sulfate About 0.30 or about 0.15 0.1 to 2.5 (expressed as sulfate) (expressed as sulfate) Ipratropium (anydrous) 0.102 0.008 to 0.5 Bromide EDTA 0.01 0.001 to 0.2 Sodium Chloride 0.82 0 to 0.9 1N HCl 0.046 0 to 1.4 Purified water q.s. q.s. The figures and attachments herein are presented for illustrative proposes only. They are not intended to limit the scope of the invention. Further, it should be understood that various changes and modifications to the presently preferred embodiment described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be covered by the appended claims. Also, the invention may suitably comprise, consist of or consist essentially of the elements described herein, and the invention described herein suitably may be practiced in the absence of any element that is not specifically disclosed herein. | <SOH> III. BACKGROUND OF INVENTION <EOH>Chronic obstructive pulmonary disease (COPD) is a slowly progressive airway disease that produces a decline in lung function that is not fully reversible. The airway limitation in COPD is associated with an abnormal inflammatory response of the lungs to noxious particles or gases. In the U.S., an estimated 16 million Americans have been diagnosed with some form of COPD, and as many as 16 million others have the condition but have not yet been diagnosed. According to the U.S. Centers for Disease Control and Prevention, COPD is the fourth leading cause of death in the U.S. (behind heart disease, cancer and stroke), claiming the lives of 112,000 Americans annually. In terms of health care utilization, the number of physician visits for COPD in the U.S. increased from 9.3 million to 16 million between 1985 and 1995. The number of hospitalizations for COPD in 1995 was estimated to be about 500,000. Although prevalence, hospitalization and death rates for COPD are higher in men than women, death rates have risen faster in women in recent years. COPD is clearly a major and growing health care threat in the U.S. and throughout the rest of the world. In the prior art, antimicrobial agents such as benzalkonium chloride (BAC) are often present in inhalation solutions used to treat COPD. The presence of BAC in these solutions generally does not affect the short-term (single dose) bronchodilator response. However, case reports suggest that repeated use of COPD treatments with BAC may result in paradoxic bronchoconstriction. When inhaled by COPD subjects, BAC may also cause dose-dependent bronchoconstriction. Despite these side effects, many commercially available inhalation solutions contain BAC. In addition, treatments for COPD often come in multiple dosage units and must be diluted to specific concentrations suitable for treating patients. This poses several problems. For instance, COPD treatments requiring administration of a single dose unit from multiple dosage units sometimes lack proper mixing or diluting instructions, or the instructions for preparing and using the COPD treatment may be hard to follow or can be easily lost. Of even greater import is haphazard diluting or mixing of COPD medications, which can result in administering the wrong dosage. This could be especially harmful for patients less tolerant to higher dosages of asthma medications. Incorrect mixing can also result in treatment failure such that additional medical attention is required, thereby increasing the time, expense and personnel costs associated with therapy. There is, therefore, a need for an improved inhalation solution, system, kit and method for relieving symptoms associated with COPD. | <SOH> IV. SUMMARY OF THE INVENTION <EOH>One object of the present invention is to provide a dual bronchodilator inhalation solution to relieve bronchospasm in patients suffering from COPD. Another object of the present invention is to provide a prepackaged, sterile, premixed, premeasured albuterol and ipratropium inhalation solution for the relief of bronchospasm in patients suffering from COPD. It is yet another object of the present invention to provide a BAC-free albuterol and ipratropium inhalation solution to treat bronchospasm associated with COPD. A further object of the present invention is to provide a method of administering an albuterol and ipratropium inhalation formulation for relief of bronchospasm associated with COPD. An additional object of the present invention is to provide a kit and/or system for administering a dual bronchodilator to relieve bronchospasm associated with COPD. A further object of the present invention is to provide a process for making an albuterol and ipratropium inhalation solution for use in relieving bronchospasm associated with COPD. Another object of the invention includes a device for use in relieving the symptoms of COPD. Other objects, features and advantages of the present invention will be apparent to those of ordinary skill in the art in view of the following detailed description of the invention and accompanying drawings. | 20050118 | 20111227 | 20050922 | 99580.0 | 0 | WESTERBERG, NISSA M | ALBUTEROL AND IPRATROPIUM INHALATION SOLUTION, SYSTEM, KIT AND METHOD FOR RELIEVING SYMPTOMS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,037,575 | ACCEPTED | Variable abstraction | System and method for creating, configuring, representing, and using variables in programs. A graphical user interface (GUI) may be displayed in response to user input requesting creation and/or configuration of a variable for use in or comprised in one or more programs, e.g., on various devices. User input is received to the GUI configuring attributes of the variable, including: name, data type, and/or scope (e.g., local, global, or network). The configured attributes are stored and optionally displayed, e.g., in a resource tree, and the variable in each of the programs updated in accordance with the configured attributes. When at least one of the programs is incompatible with the configured variable, an error condition may be indicated, e.g., by providing information relating to portions of the program that are incompatible with the configured variable. The program may be modified in response to user input for compatibility with the configured variable. | 1. A computer-implemented method for configuring a variable for use in one or more programs, the method comprising: displaying a graphical user interface (GUI) in response to user input requesting configuration of a variable, wherein the variable is comprised in one or more programs; receiving user input to the GUI configuring attributes of the variable, wherein the attributes comprise one or more of: name; data type; and scope; storing the configured attributes; and updating the variable in each of the one or more programs in accordance with the configured attributes. 2. The method of claim 1, wherein the scope comprises one of: local; global; and network. 3. The method of claim 1, wherein at least one of the one or more programs is incompatible with the configured variable, the method further comprising: indicating an error condition for said at least one of the one or more programs. 4. The method of claim 1, wherein indicating an error condition for said at least one of the one or more programs comprises: providing information relating to one or more portions of the program that are incompatible with the configured variable. 5. The method of claim 1, the method further comprising: modifying the at least one of the one or more programs in response to user input, wherein the modified at least one program is compatible with the configured variable. 6. The method of claim 1, further comprising: creating the variable, wherein said creating comprises: displaying the graphical user interface (GUI) in response to user input requesting creation of the variable; and instantiating the variable; and including the variable in the one or more programs in response to user input. 7. The method of claim 6, wherein said creating further comprises: receiving user input to the GUI specifying the attributes of the variable, wherein the attributes comprise said one or more of: name; data type; and scope; storing the specified attributes; and displaying a representation of the variable, wherein the variable is selectable via the representation for inclusion in the one or more programs. 8. The method of claim 7, wherein the representation of the variable comprises one or more of: the name; and an icon. 9. The method of claim 7, wherein said including the variable in the one or more programs comprises creating one or more variable references in the one or more programs. 10. The method of claim 9, wherein said instantiating the variable further comprises: deploying the variable to a memory location, wherein the one or more variable references in the one or more programs operate to access the memory location. 11. The method of claim 7, wherein said including the variable in the one or more programs further comprises: modifying the one or more programs to access the variable based on respective target platforms of the one or more programs 12. The method of claim 7, wherein said displaying a representation of the variable comprises displaying the representation of the variable in a window, wherein the representation is selectable via user input to the window. 13. The method of claim 12, wherein said displaying the representation of the variable in the window comprises: displaying one or more locations where the variable is deployed. 14. The method of claim 12, wherein said displaying one or more locations where the variable is deployed comprises: displaying the variable in one or more resource trees. 15. The method of claim 6, wherein said creating the variable comprises creating the variable with a default configuration of the attributes of the variable. 16. The method of claim 1, wherein the one or more programs are comprised on a plurality of devices coupled via a network. 17. The method of claim 16, wherein at least one of the plurality of devices comprises a programmable hardware element. 18. The method of claim 1, wherein the one or more programs comprise a graphical program. 19. The method of claim 18, wherein the graphical program comprises a plurality of interconnected nodes that visually indicate functionality of the graphical program. 20. The method of claim 18, wherein the graphical program comprises a block diagram portion and a user interface portion. 21. The method of claim 20, further comprising: executing the graphical program. 22. The method of claim 21, wherein, during execution of the graphical program, the graphical user interface is displayed on a display of a first computer system and the block diagram executes on a second computer system. 23. The method of claim 18, wherein the graphical program comprises a graphical data flow program. 24. The method of claim 18, wherein the graphical program is operable to perform one or more of: an industrial automation function; a process control function; a test and measurement function. 25. A memory medium that stores program instructions for configuring a variable for use in one or more programs, wherein the program instructions are executable by a computer to perform: displaying a graphical user interface (GUI) in response to user input requesting configuration of a variable, wherein the variable is comprised in one or more programs; receiving user input to the GUI configuring attributes of the variable, wherein the attributes comprise one or more of: name; data type; and scope; storing the configured attributes; and updating the variable in each of the one or more programs in accordance with the configured attributes. 26. A system for configuring a variable for use in one or more programs, comprising: a processor; a memory medium coupled to the processor; and a display device coupled to the processor and the memory medium; wherein the memory medium stores program instructions which are executable by the processor to: display a graphical user interface (GUI) on the display device in response to user input requesting configuration of a variable, wherein the variable is comprised in one or more programs; receive user input to the GUI configuring attributes of the variable, wherein the attributes comprise one or more of: name; data type; and scope; store the configured attributes; and update the variable in each of the one or more programs in accordance with the configured attributes. 27. A system for configuring a variable for use in one or more programs, the system comprising: means for displaying a graphical user interface (GUI) in response to user input requesting configuration of a variable, wherein the variable is comprised in one or more programs; means for receiving user input to the GUI configuring attributes of the variable, wherein the attributes comprise one or more of: name; data type; and scope; means for storing the configured attributes; and means for updating the variable in each of the one or more programs in accordance with the configured attributes. 28. A computer-implemented method for creating a variable for use in a program, the method comprising: displaying a graphical user interface (GUI) in response to user input requesting creation of a variable; receiving user input to the GUI specifying attributes of the variable, wherein the attributes comprise one or more of: name; data type; and scope; storing the specified attributes; and instantiating the variable in accordance with the specified attributes; and displaying a representation of the variable, wherein the variable is selectable via the representation for inclusion in a program. | PRIORITY DATA This application claims benefit of priority to U.S. Provisional Application Ser. No. 60/602,214 titled “Variable Abstraction”, filed Aug. 17, 2004, whose inventors are Steven W. Rogers, Robert E. Dye, and Ross E. Houston. FIELD OF THE INVENTION The present invention relates to the field of programming, and more particularly to a system and method for creating, configuring, representing, and using variables in programs. DESCRIPTION OF THE RELATED ART The use of variables is a fundamental part of software programming. As is well known, the term “variable” generally refers to a named memory location in which a program can store intermediate results and from which it can then read them. Each programming language has different rules about how variables can be named, typed, and used. Typically, a value is “assigned” to a variable in an assignment statement or during initialization. Variables may be of various types, including, for example, such intrinsic data types as integer, Boolean, character, and float (real), among others. Many languages also allow user-defined types, where, for example, a user may define a structure or class as a new data type, and instantiate variables of that type. Thus, a type may specify a single (“atomic”) value or a collection (“aggregate”) of values of the same or different types. A variable generally has a name, whereby the variable may be specified or referred to in and by program instructions, and which may provide a mnemonic for users indicating the nature or content of the variable. A variable's type specifies the size (e.g., in bits) of the storage needed to store the variable's contents, and generally does not change. Variables also typically have a scope, which refers to the region of program source within which it represents a specified datum or data object. Most programming languages support both local and global variables. When users develop programs that share data, there are numerous decisions they must make regarding variable attributes, e.g., type and scope. For example, if they are sharing the data between different loops in the same program, they may use local variables. For sharing data between programs running on the same machine they may use global variables. For sharing data across machines, i.e., over a network, there are many different techniques and application programming interfaces (APIs) available, including, for example, DataSocket, TCP/IP, and Logos. However, if the developer changes his mind and decides that data shared in one scope really should be shared in a different scope (i.e., a global variable that really should be shared across machines) a significant rewrite of the programs is generally required. Similarly, a change in the data type of a shared variable used in different programs, possibly across multiple machines, may entail substantial reworking of the program code. For example, there are many different ways to share data or communicate between two independent loops in a program. If the two loops are in the same program a local variable may be appropriate. If the two loops are in different programs, but on the same machine and in the same process, global variables may be used. If the two programs are in different processes or on different machines there are a number of different application programming interfaces (APIs) and protocols to choose from including (but not limited to) raw TCP, raw UDP, DataSocket, Logos, RT protocol, or VISA. The communication mechanism chosen by a user may depend on the communication characteristics desired as well as the execution target of a program. Examples include: 1. When sharing data between two different programs a user cannot use a local variable which may be only valid for sharing data within a single program. 2. When sharing data from within a time critical loop on a real-time target, e.g., on a LabVIEW Real-time target, the user may utilize real time first-in, first-out buffers (RT-FIFOs) to reduce the jitter generated. 3. When sharing data from a programmable hardware element based device, such as a field programmable gate array (FPGA) device, a user may not be able to use TCP or DataSocket, as they may not be supported on these (e.g., FPGA based) devices. Thus, it may be difficult for the user to know or decide which of these mechanisms to use for such data communications. Generally, users rewrite portions of their application or applications if they need to switch mechanisms for additional functionality or to run on different targets. For example, if a user writes an application that shares data between two loops the user may utilize global variables. FIG. 1A illustrates a prior art use of a global variable for sharing data between two loops in a graphical program, in this particular case, a LabVIEW block diagram, as may be developed in the LabVIEW graphical program development environment provided by National Instruments Corporation. It should be noted that this approach also applies to text-based programs, such as, for example, programs written in C, C++, JAVA, and so forth. As FIG. 1A shows, in the top loop, a global variable “Temperature” is declared, where the global scope is indicated by the “globe” icon. As FIG. 1A also shows, the variable is also used in the bottom loop, thus, the value of the global variable is accessible by program code in both loops. However, if the user then needs for the loops to run on two different machines, the use of global variables no longer suffices. In one prior art approach, the user may utilize an inter-machine communication mechanism, such as, for example, DataSocket, as is well known in the art. Since the APIs for global variables and DataSocket are entirely different, the user may be required to rewrite the loops. For example, FIG. 1B illustrates the graphical program of FIG. 1A, but modified to use DataSocket instead of the global variable, according to one prior art approach. As FIG. 1B shows, for each loop, the DataSocket is declared, i.e., as a Write or a Read, whereby the temperature data may be shared between the loops. However, as indicated, each of these approaches requires the user to write or modify the application specifically to implement the desired communication scheme. As noted above, if the communication scheme is used for numerous programs, possibly across many machines, changing the scheme may be difficult, tedious, and error prone. Thus, improved systems and methods for specifying, representing, and using variables are desired. SUMMARY OF THE INVENTION One embodiment of the present invention comprises a system and method for specifying, representing, and using variables in programs. The methods described may be used in conjunction with any of various computer systems or devices, including multiple devices coupled over a network. A graphical user interface (GUI) may be displayed in response to user input requesting configuration of a variable, where the variable is included in one or more programs. The programs may be text-based programs or graphical programs, and may be on a single machine or on a plurality of devices coupled via a network. User input to the GUI configuring attributes of the variable may be received. In preferred embodiments, the attributes may include one or more of: name, data type, and scope. In one embodiment, the scope may be specified as local, global, or network, where network scope refers to a variable scope spanning a plurality of machines coupled together over a network. The GUI may include various fields for specifying these attributes, for example, the user may specify a variable with the name “Temperature”, of data type “Double”, and with “Network” scope. In some embodiments, additional (optional) fields or controls may also be provided. For example, depending upon the attributes specified, e.g., data type or scope, options or fields for specifying additional attributes, e.g., buffer size, may be presented. Thus, in some embodiments, the GUI may display different and/or additional fields or controls based on the specified attributes. The configured attributes may then be stored, e.g., in non-volatile memory and/or RAM of a host computer, or of another computer or device coupled to the computer, e.g., over a network. Finally, the variable may be updated in each of the one or more programs in accordance with the configured attributes. In other words, everywhere the variable has been referenced, i.e., in different programs, possibly across multiple devices over the network, the instances of the variable, along with any underlying implementation mechanisms and/or protocols, may be automatically updated to reflect the specified configuration. In some cases, at least one of the one or more programs may be incompatible with the configured variable, in which case an error condition may be indicated for the at least one of the one or more programs. For example, in one embodiment, indicating an error condition for the at least one of the one or more programs may include providing information relating to one or more portions of the program that are incompatible with the configured variable. The at least one of the one or more programs may then be modified in response to user input, where the modified at least one program is compatible with the configured variable. Said another way, if an error is reported or otherwise indicated for one or the program instances due to incompatibility with the new variable configuration, the user may edit the program to correct the error condition. Of course, in some cases the user may also re-configure the variable, i.e., configure the variable differently, to remove the error condition. The error condition may be indicated in any of a variety of ways. For example, a text message describing the error may be presented to the user, or an error code presented, whereby the user may look up the error description. In some embodiments, the error may be indicated graphically, e.g., if the method determines that there are incompatible or invalid portions of the program, the incompatible portions may be graphically indicated, e.g., the graphical program may be displayed with broken wires indicating the incompatible portion or portions. In other embodiments, the incompatible portions may be indicated via modified icons, color-coding, shading, boundary lines, or via any other type of graphical indicator. In yet another embodiment, the invalid portions may be indicated via text, e.g., via labels displayed next to the respective portions, and so forth. In one embodiment, information indicating how the incompatible portions can be modified or replaced to enable proper use of the variable may be provided to the user, after which the user may modify the program accordingly. In some embodiments, the basic approach described above may also be used to create and specify the variable. In other words, in some embodiments, the method may also include creating the variable, e.g., with default or user-specified attributes. For example, creating the variable may include displaying the graphical user interface (GUI) in response to user input requesting creation of the variable. In some embodiments, the variable may be created with a default configuration of the attributes of the variable. If the user is satisfied with the default variables, no further configuration may be necessary. However, if there is no default configuration, or if further configuration is required, then, as described above, user input to the GUI may be received specifying the attributes of the variable. As described above, the attributes may include one or more of: name, data type, and scope. The specified (or default) attributes may be stored. Once the variable has been specified, a representation of the variable may be displayed, where the variable is selectable via the representation for inclusion in the one or more programs. For example, the representation of the variable may include the name of the variable and/or an icon for the variable. Thus, once the variable has been specified, the variable may be instantiated, and included in the one or more programs in response to user input, e.g., with a simple single point API. Note that regardless of the configuration changes made to the variable, the usage (reference) in the program(s), e.g., in or on the block diagram(s) may always be the same. In other words, the usage of the variable may not change, even if the underlying implementation of the variable changes. Thus, for example, in a graphical program embodiment, the underlying implementation for a variable may be scripted under the node visible to the user. If a user creates a variable and specifies a global scope, the underlying implementation may use a traditional global variable. If a user selects a network scope, the underlying implementation may use a mechanism and protocol accordingly, e.g., DataSocket or Logos. Once the variable has been configured and deployed, or deployed and configured, the program or programs that include or utilize the configured variable may be executed, where the variable usages (references) or instances in each program exist and behave in accordance with the configuration. As noted above, the program or programs may be text-based or graphical, and may be directed to any type of application domain, as desired. For example, the program may be operable to perform one or more of: an industrial automation function, a process control function, and/or a test and measurement function, although the techniques disclosed herein may be used in any other application domain as well. In some embodiments, displaying a representation of the variable may include displaying the representation of the variable in a window, where the representation is selectable via user input to the window. For example, the GUI may include a window for displaying and editing a program or programs, as well as a project window which may display resources related to or useable by or in the program(s). For example, the project window may display software resources, e.g., in a “source” tree, and may further display hardware resources, e.g., in a “system definition” tree. In one embodiment, displaying the representation of the variable in the window may include displaying one or more locations where the variable is deployed. Thus, in one embodiment, the variable (or a representation of the variable), e.g., the “Temperature” variable of the above example, may be displayed under or proximate to the hardware on which it is deployed. Note that the Temperature variable may also displayed in the source tree. Moreover, other variables may also displayed in the source tree, but in the system definition tree may be displayed under or proximate to a different target device. In other words, each variable may be displayed under the target device (including, for example, virtual devices and/or emulators) on which it is deployed. Note that in other embodiments, instead of displaying the variables in trees, the variables may be displayed in tables, lists, or diagrams, as desired. In some embodiments, a variable may be deployed to multiple targets simultaneously. A program may reference one or more of the deployed instances of the variable. Thus, for large distributed systems where users need to keep track of large numbers of variables that are spread out over numerous machines, the project window (or functional equivalent) may help the user keep track of variables and the locations to which they are deployed. As noted above, the displayed variables are preferably selectable from the window, e.g., the project window, for inclusion in one or more programs, e.g., text-based programs and/or graphical programs. For example, in the case of graphical programs, the user may select the variable with a pointing device, and may drag and drop the variable onto the graphical program or block diagram, creating a reference to the variable in accordance with the current configuration. In other words, when a user drops a variable onto a block diagram, a usage of the variable may be created, where the usage of the variable has the appropriate implementation scripted underneath it. As described above, a user may reconfigure a variable such that its underlying implementation changes, in which case all of the usages of the variable are preferably updated accordingly. In some embodiments, if the user creates a reference, e.g., by dragging and dropping the variable from the source tree onto a block diagram, and the variable has not yet been instantiated or deployed, a new instance of the variable may automatically be created, e.g., on the local or host computer, or some default device specified by the user, where the new reference may access the new instance of the variable. Thus, various embodiments of the systems and methods described above may unite a number of different communications protocols and APIs under a single abstraction, e.g., variable abstraction, where users may create and/or configure (and re-configure) variables through a configuration dialog, and may select the communication characteristics they desire. Moreover, upon configuration of the variable, all deployments of the variable may be automatically updated, whether they are in the same program, in different programs on the same machine, or in different programs on different machines. BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiment is considered in conjunction with the following drawings, in which: FIGS. 1A and 1B illustrate prior art specification and use of variables; FIG. 2A illustrates a computer system operable to execute a graphical program according to an embodiment of the present invention; FIG. 2B illustrates a network system comprising two or more computer systems that may implement an embodiment of the present invention; FIG. 3A illustrates an instrumentation control system according to one embodiment of the invention; FIG. 3B illustrates an industrial automation system according to one embodiment of the invention; FIG. 4 is an exemplary block diagram of the computer systems of FIGS. 2A, 2B, 3A and 3B; FIG. 5 is a flowchart diagram illustrating one embodiment of a method for configuring a variable; FIG. 6 illustrates one embodiment of a graphical user interface (GUI) for configuring a variable; FIG. 7 illustrates using a variable in one or more programs, according to one embodiment; and FIG. 8 illustrates one embodiment of a GUI for displaying, selecting, and deploying a variable to one or more programs. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Incorporation by Reference The following references are hereby incorporated by reference in their entirety as though fully and completely set forth herein: U.S. Provisional Application Ser. No. 60/602,214 titled “Variable Abstraction”, filed Aug. 17, 2004. U.S. Pat. No. 4,914,568 titled “Graphical System for Modeling a Process and Associated Method,” issued on Apr. 3, 1990. U.S. Pat. No. 5,481,741 titled “Method and Apparatus for Providing Attribute Nodes in a Graphical Data Flow Environment”. U.S. Pat. No. 6,173,438 titled “Embedded Graphical Programming System” filed Aug. 18, 1997. U.S. Pat. No. 6,219,628 titled “System and Method for Configuring an Instrument to Perform Measurement Functions Utilizing Conversion of Graphical Programs into Hardware Implementations,” filed Aug. 18, 1997. U.S. Patent Application Publication No. 20010020291 (Ser. No. 09/745,023) titled “System and Method for Programmatically Generating a Graphical Program in Response to Program Information,” filed Dec. 20, 2000, currently pending. Terms The following is a glossary of terms used in the present application: Memory Medium—Any of various types of memory devices or storage devices. The term “memory medium” is intended to include an installation medium, e.g., a CD-ROM, floppy disks 104, or tape device; a computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; or a non-volatile memory such as a magnetic media, e.g., a hard drive, or optical storage. The memory medium may comprise other types of memory as well, or combinations thereof. In addition, the memory medium may be located in a first computer in which the programs are executed, or may be located in a second different computer which connects to the first computer over a network, such as the Internet. In the latter instance, the second computer may provide program instructions to the first computer for execution. The term “memory medium” may include two or more memory mediums which may reside in different locations, e.g., in different computers that are connected over a network. Carrier Medium—a memory medium as described above, as well as signals such as electrical, electromagnetic, or digital signals, conveyed via a communication medium such as a bus, network and/or a wireless link. Programmable Hardware Element—includes various types of programmable hardware, reconfigurable hardware, programmable logic, or field-programmable devices (FPDs), such as one or more FPGAs (Field Programmable Gate Arrays), or one or more PLDs (Programmable Logic Devices), such as one or more Simple PLDs (SPLDs) or one or more Complex PLDs (CPLDs), or other types of programmable hardware. A programmable hardware element may also be referred to as “reconfigurable logic”. Medium—includes one or more of a memory medium, carrier medium, and/or programmable hardware element; encompasses various types of mediums that can either store program instructions/data structures or can be configured with a hardware configuration program. For example, a medium that is “configured to perform a function or implement a software object” may be 1) a memory medium or carrier medium that stores program instructions, such that the program instructions are executable by a processor to perform the function or implement the software object; 2) a medium carrying signals that are involved with performing the function or implementing the software object; and/or 3) a programmable hardware element configured with a hardware configuration program to perform the function or implement the software object. Program—the term “program” is intended to have the full breadth of its ordinary meaning. The term “program” includes 1) a software program which may be stored in a memory and is executable by a processor or 2) a hardware configuration program useable for configuring a programmable hardware element. Software Program—the term “software program” is intended to have the full breadth of its ordinary meaning, and includes any type of program instructions, code, script and/or data, or combinations thereof, that may be stored in a memory medium and executed by a processor. Exemplary software programs include programs written in text-based programming languages, such as C, C++, Pascal, Fortran, Cobol, Java, assembly language, etc.; graphical programs (programs written in graphical programming languages); assembly language programs; programs that have been compiled to machine language; scripts; and other types of executable software. A software program may comprise two or more software programs that interoperate in some manner. Hardware Configuration Program—a program, e.g., a netlist or bit file, that can be used to program or configure a programmable hardware element. Graphical Program—A program comprising a plurality of interconnected nodes or icons, wherein the plurality of interconnected nodes or icons visually indicate functionality of the program. The following provides examples of various aspects of graphical programs. The following examples and discussion are not intended to limit the above definition of graphical program, but rather provide examples of what the term “graphical program” encompasses: The nodes in a graphical program may be connected in one or more of a data flow, control flow, and/or execution flow format. The nodes may also be connected in a “signal flow” format, which is a subset of data flow. Exemplary graphical program development environments which may be used to create graphical programs include LabVIEW, DasyLab, DiaDem and Matrixx/SystemBuild from National Instruments, Simulink from the MathWorks, VEE from Agilent, WiT from Coreco, Vision Program Manager from PPT Vision, SoftWIRE from Measurement Computing, Sanscript from Northwoods Software, Khoros from Khoral Research, SnapMaster from HEM Data, VisSim from Visual Solutions, ObjectBench by SES (Scientific and Engineering Software), and VisiDAQ from Advantech, among others. The term “graphical program” includes models or block diagrams created in graphical modeling environments, wherein the model or block diagram comprises interconnected nodes or icons that visually indicate operation of the model or block diagram; exemplary graphical modeling environments include Simulink, SystemBuild, VisSim, Hypersignal Block Diagram, etc. A graphical program may be represented in the memory of the computer system as data structures and/or program instructions. The graphical program, e.g., these data structures and/or program instructions, may be compiled or interpreted to produce machine language that accomplishes the desired method or process as shown in the graphical program. Input data to a graphical program may be received from any of various sources, such as from a device, unit under test, a process being measured or controlled, another computer program, a database, or from a file. Also, a user may input data to a graphical program or virtual instrument using a graphical user interface, e.g., a front panel. A graphical program may optionally have a GUI associated with the graphical program. In this case, the plurality of interconnected nodes are often referred to as the block diagram portion of the graphical program. Node—In the context of a graphical program, an element that may be included in a graphical program. A node may have an associated icon that represents the node in the graphical program, as well as underlying code or data that implements functionality of the node. Exemplary nodes include function nodes, terminal nodes, structure nodes, etc. Nodes may be connected together in a graphical program by connection icons or wires. Data Flow Graphical Program (or Data Flow Diagram)—A graphical program or diagram comprising a plurality of interconnected nodes, wherein the connections between the nodes indicate that data produced by one node is used by another node. Graphical User Interface—this term is intended to have the full breadth of its ordinary meaning. The term “Graphical User Interface” is often abbreviated to “GUI”. A GUI may comprise only one or more input GUI elements, only one or more output GUI elements, or both input and output GUI elements. The following provides examples of various aspects of GUIs. The following examples and discussion are not intended to limit the ordinary meaning of GUI, but rather provide examples of what the term “graphical user interface” encompasses: A GUI may comprise a single window having one or more GUI Elements, or may comprise a plurality of individual GUI Elements (or individual windows each having one or more GUI Elements), wherein the individual GUI Elements or windows may optionally be tiled together. A GUI may be associated with a graphical program. In this instance, various mechanisms may be used to connect GUI Elements in the GUI with nodes in the graphical program. For example, when Input Controls and Output Indicators are created in the GUI, corresponding nodes (e.g., terminals) may be automatically created in the graphical program or block diagram. Alternatively, the user can place terminal nodes in the block diagram which may cause the display of corresponding GUI Elements front panel objects in the GUI, either at edit time or later at run time. As another example, the GUI may comprise GUI Elements embedded in the block diagram portion of the graphical program. Front Panel—A Graphical User Interface that includes input controls and output indicators, and which enables a user to interactively control or manipulate the input being provided to a program, and view output of the program, while the program is executing. A front panel is a type of GUI. A front panel may be associated with a graphical program as described above. In an instrumentation application, the front panel can be analogized to the front panel of an instrument. In an industrial automation application the front panel can be analogized to the MMI (Man Machine Interface) of a device. The user may adjust the controls on the front panel to affect the input and view the output on the respective indicators. Graphical User Interface Element—an element of a graphical user interface, such as for providing input or displaying output. Exemplary graphical user interface elements comprise input controls and output indicators Input Control—a graphical user interface element for providing user input to a program. Exemplary input controls comprise dials, knobs, sliders, input text boxes, etc. Output Indicator—a graphical user interface element for displaying output from a program. Exemplary output indicators include charts, graphs, gauges, output text boxes, numeric displays, etc. An output indicator is sometimes referred to as an “output control”. Computer System—any of various types of computing or processing systems, including a personal computer system (PC), mainframe computer system, workstation, network appliance, Internet appliance, personal digital assistant (PDA), television system, grid computing system, or other device or combinations of devices. In general, the term “computer system” can be broadly defined to encompass any device (or combination of devices) having at least one processor that executes instructions from a memory medium. Measurement Device—includes instruments, data acquisition devices, smart sensors, and any of various types of devices that are operable to acquire and/or store data. A measurement device may also optionally be further operable to analyze or process the acquired or stored data. Examples of a measurement device include an instrument, such as a traditional stand-alone “box” instrument, a computer-based instrument (instrument on a card) or external instrument, a data acquisition card, a device external to a computer that operates similarly to a data acquisition card, a smart sensor, one or more DAQ or measurement cards or modules in a chassis, an image acquisition device, such as an image acquisition (or machine vision) card (also called a video capture board) or smart camera, a motion control device, a robot having machine vision, and other similar types of devices. Exemplary “stand-alone” instruments include oscilloscopes, multimeters, signal analyzers, arbitrary waveform generators, spectroscopes, and similar measurement, test, or automation instruments. A measurement device may be further operable to perform control functions, e.g., in response to analysis of the acquired or stored data. For example, the measurement device may send a control signal to an external system, such as a motion control system or to a sensor, in response to particular data. A measurement device may also be operable to perform automation functions, i.e., may receive and analyze data, and issue automation control signals in response. FIG. 2A—Computer System FIG. 2A illustrates a computer system 82 operable to execute program instructions implementing embodiments of the present invention. Various embodiments of a system and method for specifying, configuring, representing, and using variables in programs are described below. As shown in FIG. 2A, the computer system 82 may include a display device operable to display an interface, such as a graphical user interface (GUI), facilitating interactions between a user and software executing on the computer system 82. For example, the graphical user interface may comprise any type of graphical user interface, e.g., depending on the computing platform. The computer system 82 may include a memory medium(s) on which one or more computer programs or software components according to one embodiment of the present invention may be stored. For example, the memory medium may store one or more programs, e.g., text-based programs or graphical programs, which are executable to perform the methods described herein. Also, the memory medium may store a programming development environment application used to create and/or execute such programs, also referred to as an integrated development environment (IDE). The memory medium may also store operating system software, as well as other software for operation of the computer system. Various embodiments further include receiving or storing instructions and/or data implemented in accordance with the foregoing description upon a carrier medium. FIG. 2B—Computer Network FIG. 2B illustrates a system including a first computer system 82 that is coupled to a second computer system 90. The computer system 82 may be connected through a network 84 (or a computer bus) to the second computer system 90. The computer systems 82 and 90 may each be any of various types, as desired. The network 84 can also be any of various types, including a LAN (local area network), WAN (wide area network), the Internet, or an Intranet, among others. The computer systems 82 and 90 may execute a program in a distributed fashion. For example, computer 82 may execute a first portion of the program and computer system 90 may execute a second portion of the program. As another example, computer 82 may display the user interface of a program and computer system 90 may execute the functional or application portion of the program. In some embodiments, the program development environment or integrated development environment (IDE) may be the LabVIEW graphical program development environment provide by National Instruments Corporation, and the programs described herein may be graphical programs developed in the “G” graphical programming language also provided by National Instruments Corporation, although the techniques described herein are broadly applicable to any type of program, including text-based programs, such as, for example, C, C++, and JAVA, among others. For example, as described above in the glossary of terms, a graphical program comprises a plurality of interconnected nodes or icons, wherein the plurality of interconnected nodes or icons visually indicate functionality of the program. These interconnected nodes form a block diagram. In some cases, the graphical program may also include a user interface portion, referred to as a front panel, which includes one or more controls or indicators for human interaction with the program. Further details regarding graphical programming may be found in the patents incorporated by reference above. In one embodiment, the graphical user interface of the graphical program may be displayed on a display device of the computer system 82, and the block diagram may execute on a device 190 connected to the computer system 82. The device 190 may include a programmable hardware element and/or may include a processor and memory medium which may execute a real time operating system. In one embodiment, the graphical program may be downloaded and executed on the device 190. For example, an application development environment with which the graphical program is associated may provide support for downloading a graphical program for execution on the device in a real time system. Exemplary Systems Embodiments of the present invention may be involved with performing test and/or measurement functions; controlling and/or modeling instrumentation or industrial automation hardware; modeling and simulation functions, e.g., modeling or simulating a device or product being developed or tested, etc. Exemplary test applications where the graphical program may be used include hardware-in-the-loop testing and rapid control prototyping, among others. However, it is noted that the present invention can be used for a plethora of applications and is not limited to the above applications. In other words, applications discussed in the present description are exemplary only, and the present invention may be used in any of various types of systems. Thus, the system and method of the present invention is operable to be used in any of various types of applications, including the control of other types of devices such as multimedia devices, video devices, audio devices, telephony devices, Internet devices, etc., as well as general purpose software applications such as word processing, spreadsheets, network control, network monitoring, financial applications, games, etc. FIG. 3A illustrates an exemplary instrumentation control system 100 which may implement embodiments of the invention. The system 100 comprises a host computer 82 which connects to one or more instruments. The host computer 82 may comprise a CPU, a display screen, memory, and one or more input devices such as a mouse or keyboard as shown. The computer 82 may operate with the one or more instruments to analyze, measure or control a unit under test (UUT) or process 150. The one or more instruments may include a GPIB instrument 112 and associated GPIB interface card 122, a data acquisition board 114 and associated signal conditioning circuitry 124, a VXI instrument 116, a PXI instrument 118, a video device or camera 132 and associated image acquisition (or machine vision) card 134, a motion control device 136 and associated motion control interface card 138, and/or one or more computer based instrument cards 142, among other types of devices. The computer system may couple to and operate with one or more of these instruments. The instruments may be coupled to a unit under test (UUT) or process 150, or may be coupled to receive field signals, typically generated by transducers. The system 100 may be used in a data acquisition and control application, in a test and measurement application, an image processing or machine vision application, a process control application, a man-machine interface application, a simulation application, or a hardware-in-the-loop validation application, among others. While the techniques described herein are illustrated in terms of various industrial applications, it should be noted that they are broadly applicable to any program application or domain. FIG. 3B illustrates an exemplary industrial automation system 160 which may implement embodiments of the invention. The industrial automation system 160 is similar to the instrumentation or test and measurement system 100 shown in FIG. 3A. Elements which are similar or identical to elements in FIG. 3A have the same reference numerals for convenience. The system 160 may comprise a computer 82 which connects to one or more devices or instruments. The computer 82 may comprise a CPU, a display screen, memory, and one or more input devices such as a mouse or keyboard as shown. The computer 82 may operate with the one or more devices to a process or device 150 to perform an automation function, such as MMI (Man Machine Interface), SCADA (Supervisory Control and Data Acquisition), portable or distributed data acquisition, process control, advanced analysis, or other control, among others. The one or more devices may include a data acquisition board 114 and associated signal conditioning circuitry 124, a PXI instrument 118, a video device 132 and associated image acquisition card 134, a motion control device 136 and associated motion control interface card 138, a fieldbus device 170 and associated fieldbus interface card 172, a PLC (Programmable Logic Controller) 176, a serial instrument 182 and associated serial interface card 184, or a distributed data acquisition system, such as the Fieldpoint system available from National Instruments, among other types of devices. FIG. 4—Computer System Block Diagram FIG. 4 is a block diagram representing one embodiment of the computer system 82 and/or 90 illustrated in FIGS. 2A and 2B, or computer system 82 shown in FIG. 3A or 3B. It is noted that any type of computer system configuration or architecture can be used as desired, and FIG. 4 illustrates a representative PC embodiment. It is also noted that the computer system may be a general purpose computer system, a computer implemented on a card installed in a chassis, or other types of embodiments. Elements of a computer not necessary to understand the present description have been omitted for simplicity. The computer may include at least one central processing unit or CPU (processor) 160 which is coupled to a processor or host bus 162. The CPU 160 may be any of various types, including an x86 processor, e.g., a Pentium class, a PowerPC processor, a CPU from the SPARC family of RISC processors, as well as others. A memory medium, typically comprising RAM and referred to as main memory, 166 is coupled to the host bus 162 by means of memory controller 164. The main memory 166 may store a program development environment and one or more programs in accordance with various embodiments of the present invention. The main memory may also store operating system software, as well as other software for operation of the computer system. The host bus 162 may be coupled to an expansion or input/output bus 170 by means of a bus controller 168 or bus bridge logic. The expansion bus 170 may be the PCI (Peripheral Component Interconnect) expansion bus, although other bus types can be used. The expansion bus 170 includes slots for various devices such as described above. The computer 82 further comprises a video display subsystem 180 and hard drive 182 coupled to the expansion bus 170. As shown, a device 190 may also be connected to the computer. The device 190 may include a processor and memory which may execute a real time operating system. The device 190 may also or instead comprise a programmable hardware element. The computer system may be operable to deploy a program to the device 190 for execution of the program on the device 190. The deployed program may take the form of a text-based program, or may comprise a graphical program. The deployed graphical program may comprise graphical program instructions or data structures that directly represents the graphical program. Alternatively, the deployed graphical program may take the form of text code (e.g., C code) generated from the graphical program. As another example, the deployed graphical program may take the form of compiled code generated from either the graphical program or from text code that in turn was generated from the graphical program. FIG. 5—Method for Configuring a Variable FIG. 5 flowcharts one embodiment of a method for configuring a variable for use in one or more programs. The method shown in FIG. 5 may be used in conjunction with any of the computer systems or devices shown in the above Figures, among other devices. In various embodiments, some of the method elements shown may be performed concurrently, in a different order than shown, or may be omitted. Additional method elements may also be performed as desired. As shown, this method may operate as follows. In 502, a graphical user interface (GUI) may be displayed in response to user input requesting configuration of a variable, where the variable is included in one or more programs, where, as noted above, the programs may be text-based programs or graphical programs, and may be on a single machine or on a plurality of devices coupled via a network. FIG. 6 illustrates one embodiment of such a GUI, although it should be noted that the GUI of FIG. 6 is meant to be exemplary only, and is not intended to limit the GUI to any particular form, function, or appearance. In 504, user input to the GUI configuring attributes of the variable may be received. In preferred embodiments, the attributes may include one or more of: name, data type, and scope. In one embodiment, the scope may be specified as local, global, or network, where network scope refers to a variable scope spanning a plurality of machines coupled together over a network. As FIG. 6 shows, the example GUI includes various fields for specifying these attributes, where, as may be seen, the user has specified a variable with the name “Temperature”, of data type “Double”, and with “Network” scope. As shown in the example GUI of FIG. 6, in some embodiments, additional (optional) fields or controls may also be provided. For example, depending upon the attributes specified, e.g., data type or scope, options or fields for specifying additional attributes may be presented, such as the “Features” list shown in the bottom left portion of the GUI. These features, namely “Network Buffering” and “RT FIFO” correspond to the network scope of the variable. As shown, the user has selected “Network Buffering”, which refers to storage used in communicating the variable's value over the network. As also shown, corresponding to this feature, controls may be provided for setting the buffer size, e.g., in terms of size in bytes, or number of elements. Thus, in some embodiments, the GUI may display different and/or additional fields or controls based on the specified attributes. In this example, an “Advanced” button is also provided whereby the user may invoke additional dialogs for specifying further attributes of or related to the variable. For example, in one embodiment, the user may be allowed to specify a particular communication protocol for implementing the network-scoped variable, e.g., DataSocket, Logos, or TCP, among others. In some embodiments, the term “scope” may have a slightly different meaning than that traditionally associated with program variables. For example, the scope specified in 504 may refer to the scope of the variable definition and the access domain of any instance of the variable based on the definition. Thus, if the user specifies that the variable being defined have network scope, the variable definition applies across any machines on the network. Similarly, any instances of the variable, i.e., instantiations of the defined variable, are accessible to any program on any device on the network. In other words, any program on any device in the network may include references to the variable that may access some shared memory location to which the variable has been deployed. Said another way, once the variable definition has been specified, the user may deploy the variable to a particular location, e.g., to a memory location on a hardware device, such as computer 82, or any other device coupled to the network. The value of the deployed variable is thus stored at this memory location. References to this instance of the variable (as defined by the variable definition) may then be used in any programs, subject to the specified scope, where the scope is considered with respect to the deployment location. For example, if a globally scoped variable is deployed to a particular device, say, device A, then that variable may only be accessed by programs executing on device A. Note that there may be multiple instantiations and deployments of variables based on the same variable definition. For example, in addition to the variable deployment to device A mentioned above, a second instance of the variable may be deployed to device B, which may then only be accessed by programs on device B. Because of the global scope, the respective programs on each of the devices (A and B) may only “see” their respective deployed variable instance. However, in cases where the deployed variable instances are specified with network scope, regardless of the particular deployment locations (as long as they are on the network), any programs on any devices may access both of the variable instances. Thus, although the variables may have the same visible name, some type of scope resolution may be required whereby the particular variable instance (deployment) may be specified for reference. For example, in one embodiment, the variable instances may include scope resolution or deployment information, e.g., an instance designation, which may be used to distinguish between multiple instances of the variable. It should be noted that in addition to scope, access to a particular instance of a variable may also be constrained to specific devices on the network. For example, this type of constraint may be specified by security configurations, such as for example, a list of devices or programs or users which may be allowed access. In 506, the configured attributes may be stored, e.g., in non-volatile memory and/or RAM of the host computer 82, or of another computer or device coupled to the computer, e.g., over a network. Finally, in 508, the variable may be updated in each of the one or more programs in accordance with the configured attributes. In other words, everywhere the variable has been instantiated and referenced, i.e., in different programs, possibly across multiple devices over the network, the instances and references of the variable, along with any underlying implementation mechanisms and/or protocols, may be automatically updated to reflect the specified configuration. In some cases, at least one of the one or more programs may be incompatible with the configured variable, in which case an error condition may be indicated for the at least one of the one or more programs. For example, in one embodiment, indicating an error condition for the at least one of the one or more programs may include providing information relating to one or more portions of the program that are incompatible with the configured variable. The at least one of the one or more programs may then be modified in response to user input, where the modified at least one program is compatible with the configured variable. Said another way, if an error is reported or otherwise indicated for one or the program instances due to incompatibility with the new variable configuration, the user may edit the program to correct the error condition. Of course, in some cases the user may also re-configure the variable, i.e., configure the variable differently, to remove the error condition. The error condition may be indicated in any of a variety of ways. For example, a text message describing the error may be presented to the user, or an error code presented, whereby the user may look up the error description. In some embodiments, the error may be indicated graphically, e.g., if the method determines that there are incompatible or invalid portions of the program, the incompatible portions may be graphically indicated, e.g., the graphical program may be displayed with broken wires indicating the incompatible portion or portions. In other embodiments, the incompatible portions may be indicated via modified icons, color-coding, shading, boundary lines, or via any other type of graphical indicator. In yet another embodiment, the invalid portions may be indicated via text, e.g., via labels displayed next to the respective portions, and so forth. In one embodiment, information indicating how the incompatible portions can be modified or replaced to enable proper use of the variable may be provided to the user, after which the user may modify the program accordingly. In some embodiments, the basic approach described above may also be used to create and specify the variable. In other words, in some embodiments, the method of FIG. 5 may also include creating the variable, e.g., with default or user-specified attributes. For example, creating the variable may include displaying the graphical user interface (GUI) in response to user input requesting creation of the variable. In some embodiments, the variable may be created with a default configuration of the attributes of the variable. If the user is satisfied with the default variables, no further configuration may be necessary. However, if there is no default configuration, or if further configuration is required, then, as described above with reference to FIG. 5, user input to the GUI may be received specifying the attributes of the variable. As described above, the attributes may include one or more of: name, data type, and scope. The specified (or default) attributes may be stored. Once the variable has been specified, a representation of the variable may be displayed, where the variable is selectable via the representation for inclusion in the one or more programs. For example, the representation of the variable may include the name of the variable and/or an icon for the variable. An example of such a representation and its display is described below with reference to FIG. 8. FIG. 7—Using Variables in Programs Once the variable has been specified, the variable may be instantiated, and references to the variable included in the one or more programs in response to user input. In other words, the variable may be instantiated based on the variable definition, and deployed to some (possibly shared) memory location, after which one or more programs may reference the variable. FIG. 7 illustrates use of a variable in separate looping structures, according to one embodiment. Note that the two loops may be in the same program, in different programs on the same machine, or in different programs on different machines. Note that the variable is simply declared and used in the loops (programs), with no external or visible indication of the underlying implementation. Note also, however, that in the embodiment shown in FIG. 7, the variable node or icon does indicate some configuration information of the variable, specifically, the network scope of the variable, as indicated by the network icon displayed just to the left of the variable name. Thus, as indicated above, once the variable is configured and instantiated it may be used on or in one or more programs, e.g., block diagrams or graphical program, with a simple single point API. Note that regardless of the configuration changes made to the variable, the usage in the program(s), e.g., in or on the block diagram(s) may always be the same. In other words, the usage of the variable may not change, even if the underlying implementation of the variable changes. Thus, for example, in a graphical program embodiment, the underlying implementation for a variable may be scripted under the node visible to the user. If a user creates a variable and specifies a global scope, the underlying implementation may use a traditional global variable (as illustrated in FIG. 1A). If a user selects a network scope, the underlying implementation may use a mechanism and protocol accordingly, e.g., DataSocket or Logos. Once the variable has been configured and deployed, or deployed and configured, the program or programs that include or reference the configured variable may be executed, where the variable usages, instances, or references in each program exist and behave in accordance with the configuration. As noted above, the program or programs may be text-based or graphical, and may be directed to any type of application domain, as desired. For example, the program may be operable to perform one or more of: an industrial automation function, a process control function, and/or a test and measurement function, among others. FIG. 8—Displaying and Selecting the Variable for Use As noted above, in some embodiments, once the variable has been specified or configured, a representation of the variable may be displayed, where the representation of the variable is selectable by the user to include the variable in a program. For example, in some embodiments, displaying a representation of the variable may include displaying the representation of the variable in a window, where the representation is selectable via user input to the window. FIG. 8 illustrates one embodiment of a GUI for displaying and selecting variables, e.g., for use in a program or programs, and/or for configuring the variable. As FIG. 8 shows, in this embodiment, the GUI includes a window for displaying and editing a program or programs, as well as a project window which may display resources related to or useable by or in the program(s). For example, as shown, the project window may display software resources, e.g., in a “source” tree, and may further display hardware resources, e.g., in a “system definition” tree. Thus, resource trees may be used to display representations of the variable. In one embodiment, displaying the representation of the variable in the window may include displaying one or more locations where the variable is deployed. Thus, as FIG. 8 indicates, in one embodiment, the variable (or a representation of the variable), e.g., the “Temperature” variable of the above examples, may be displayed under or proximate to the hardware on which it is deployed. Note that the Temperature variable is also displayed in the source tree. Moreover, in this particular example, another variable, “Pressure” is also displayed in the source tree, but in the system definition tree is displayed under or proximate to a PXI RT Target element in the tree. In other words, each variable may be displayed under the target device (including, for example, virtual devices and/or emulators) on which it is deployed. Note that as mentioned above, multiple instances of the variable may be deployed onto different respective devices. Thus, for large distributed systems where users need to keep track of large numbers of variables that are spread out over numerous machines, the project window (or functional equivalent) may help the user keep track of variables and the locations to which they are deployed. It should be noted that the particular embodiment shown in FIG. 8 is meant to be exemplary only, and is not intended to limit the variable representation or display to any particular form, function, or appearance. For example, instead of displaying the variables in trees, the variables may be displayed in tables, lists, diagrams, and so forth, as desired. As noted above, the displayed variables are preferably selectable from the window, e.g., the project window, for inclusion in one or more programs, e.g., text-based programs and/or graphical programs. For example, in the case of graphical programs, the user may select the variable with a pointing device, and may drag and drop the variable onto the graphical program or block diagram, thereby creating a reference to the variable, i.e., creating a “usage” of the variable, in accordance with the current configuration. In other words, when a user drops a variable onto a block diagram, a usage of the variable may be created, where the usage of the variable has the appropriate implementation scripted underneath it. As described above, a user may reconfigure a variable such that its underlying implementation changes, in which case all of the usages of the variable are preferably updated accordingly. In some embodiments, if the user creates a reference, e.g., by dragging and dropping the variable from the source tree onto a block diagram, and the variable has not yet been instantiated or deployed, a new instance of the variable may automatically be created, e.g., on the local or host computer, or some default device specified by the user, where the new reference may access the new instance of the variable. Graphical Programs and Programming As noted above, in some embodiments, the programs described herein may be graphical programs. A graphical program may be created on the computer system 82 (or on a different computer system) in the following manner. The graphical program may be created or assembled by the user arranging on a display a plurality of nodes or icons and then interconnecting the nodes to create the graphical program. In response to the user assembling the graphical program, data structures may be created and stored which represent the graphical program. The nodes may be interconnected in one or more of a graphical data flow, control flow, or execution flow format. The graphical program may thus comprise a plurality of interconnected nodes or icons which visually indicates the functionality of the program. As noted above, the graphical program may comprise a block diagram and may also include a user interface portion or front panel portion. Where the graphical program includes a user interface portion, the user may optionally assemble the user interface on the display. As one example, the user may use the LabVIEW graphical programming development environment to create the graphical program. In an alternate embodiment, the graphical program may be created in 262 by the user creating or specifying a prototype, followed by automatic or programmatic creation of the graphical program from the prototype. This functionality is described in U.S. patent application Ser. No. 09/587,682 titled “System and Method for Automatically Generating a Graphical Program to Perform an Image Processing Algorithm”, which is hereby incorporated by reference in its entirety as though fully and completely set forth herein. The graphical program may be created in other manners, either by the user or programmatically, as desired. In some embodiments where the graphical program comprises a block diagram portion and a user interface portion, during execution of the graphical program, the graphical user interface is displayed on a display of a first computer system and the block diagram executes on a second computer system. Thus, various embodiments of the systems and methods described above may unite a number of different communications protocols and APIs under a single abstraction, e.g., variable abstraction, where users may create and/or configure (and re-configure) variables through a configuration dialog, and may select the communication characteristics they desire. Moreover, upon configuration of the variable, all deployments of the variable may be automatically updated, whether they are in the same program, in different programs on the same machine, or in different programs on different machines. Although the embodiments above have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications. | <SOH> FIELD OF THE INVENTION <EOH>The present invention relates to the field of programming, and more particularly to a system and method for creating, configuring, representing, and using variables in programs. | <SOH> SUMMARY OF THE INVENTION <EOH>One embodiment of the present invention comprises a system and method for specifying, representing, and using variables in programs. The methods described may be used in conjunction with any of various computer systems or devices, including multiple devices coupled over a network. A graphical user interface (GUI) may be displayed in response to user input requesting configuration of a variable, where the variable is included in one or more programs. The programs may be text-based programs or graphical programs, and may be on a single machine or on a plurality of devices coupled via a network. User input to the GUI configuring attributes of the variable may be received. In preferred embodiments, the attributes may include one or more of: name, data type, and scope. In one embodiment, the scope may be specified as local, global, or network, where network scope refers to a variable scope spanning a plurality of machines coupled together over a network. The GUI may include various fields for specifying these attributes, for example, the user may specify a variable with the name “Temperature”, of data type “Double”, and with “Network” scope. In some embodiments, additional (optional) fields or controls may also be provided. For example, depending upon the attributes specified, e.g., data type or scope, options or fields for specifying additional attributes, e.g., buffer size, may be presented. Thus, in some embodiments, the GUI may display different and/or additional fields or controls based on the specified attributes. The configured attributes may then be stored, e.g., in non-volatile memory and/or RAM of a host computer, or of another computer or device coupled to the computer, e.g., over a network. Finally, the variable may be updated in each of the one or more programs in accordance with the configured attributes. In other words, everywhere the variable has been referenced, i.e., in different programs, possibly across multiple devices over the network, the instances of the variable, along with any underlying implementation mechanisms and/or protocols, may be automatically updated to reflect the specified configuration. In some cases, at least one of the one or more programs may be incompatible with the configured variable, in which case an error condition may be indicated for the at least one of the one or more programs. For example, in one embodiment, indicating an error condition for the at least one of the one or more programs may include providing information relating to one or more portions of the program that are incompatible with the configured variable. The at least one of the one or more programs may then be modified in response to user input, where the modified at least one program is compatible with the configured variable. Said another way, if an error is reported or otherwise indicated for one or the program instances due to incompatibility with the new variable configuration, the user may edit the program to correct the error condition. Of course, in some cases the user may also re-configure the variable, i.e., configure the variable differently, to remove the error condition. The error condition may be indicated in any of a variety of ways. For example, a text message describing the error may be presented to the user, or an error code presented, whereby the user may look up the error description. In some embodiments, the error may be indicated graphically, e.g., if the method determines that there are incompatible or invalid portions of the program, the incompatible portions may be graphically indicated, e.g., the graphical program may be displayed with broken wires indicating the incompatible portion or portions. In other embodiments, the incompatible portions may be indicated via modified icons, color-coding, shading, boundary lines, or via any other type of graphical indicator. In yet another embodiment, the invalid portions may be indicated via text, e.g., via labels displayed next to the respective portions, and so forth. In one embodiment, information indicating how the incompatible portions can be modified or replaced to enable proper use of the variable may be provided to the user, after which the user may modify the program accordingly. In some embodiments, the basic approach described above may also be used to create and specify the variable. In other words, in some embodiments, the method may also include creating the variable, e.g., with default or user-specified attributes. For example, creating the variable may include displaying the graphical user interface (GUI) in response to user input requesting creation of the variable. In some embodiments, the variable may be created with a default configuration of the attributes of the variable. If the user is satisfied with the default variables, no further configuration may be necessary. However, if there is no default configuration, or if further configuration is required, then, as described above, user input to the GUI may be received specifying the attributes of the variable. As described above, the attributes may include one or more of: name, data type, and scope. The specified (or default) attributes may be stored. Once the variable has been specified, a representation of the variable may be displayed, where the variable is selectable via the representation for inclusion in the one or more programs. For example, the representation of the variable may include the name of the variable and/or an icon for the variable. Thus, once the variable has been specified, the variable may be instantiated, and included in the one or more programs in response to user input, e.g., with a simple single point API. Note that regardless of the configuration changes made to the variable, the usage (reference) in the program(s), e.g., in or on the block diagram(s) may always be the same. In other words, the usage of the variable may not change, even if the underlying implementation of the variable changes. Thus, for example, in a graphical program embodiment, the underlying implementation for a variable may be scripted under the node visible to the user. If a user creates a variable and specifies a global scope, the underlying implementation may use a traditional global variable. If a user selects a network scope, the underlying implementation may use a mechanism and protocol accordingly, e.g., DataSocket or Logos. Once the variable has been configured and deployed, or deployed and configured, the program or programs that include or utilize the configured variable may be executed, where the variable usages (references) or instances in each program exist and behave in accordance with the configuration. As noted above, the program or programs may be text-based or graphical, and may be directed to any type of application domain, as desired. For example, the program may be operable to perform one or more of: an industrial automation function, a process control function, and/or a test and measurement function, although the techniques disclosed herein may be used in any other application domain as well. In some embodiments, displaying a representation of the variable may include displaying the representation of the variable in a window, where the representation is selectable via user input to the window. For example, the GUI may include a window for displaying and editing a program or programs, as well as a project window which may display resources related to or useable by or in the program(s). For example, the project window may display software resources, e.g., in a “source” tree, and may further display hardware resources, e.g., in a “system definition” tree. In one embodiment, displaying the representation of the variable in the window may include displaying one or more locations where the variable is deployed. Thus, in one embodiment, the variable (or a representation of the variable), e.g., the “Temperature” variable of the above example, may be displayed under or proximate to the hardware on which it is deployed. Note that the Temperature variable may also displayed in the source tree. Moreover, other variables may also displayed in the source tree, but in the system definition tree may be displayed under or proximate to a different target device. In other words, each variable may be displayed under the target device (including, for example, virtual devices and/or emulators) on which it is deployed. Note that in other embodiments, instead of displaying the variables in trees, the variables may be displayed in tables, lists, or diagrams, as desired. In some embodiments, a variable may be deployed to multiple targets simultaneously. A program may reference one or more of the deployed instances of the variable. Thus, for large distributed systems where users need to keep track of large numbers of variables that are spread out over numerous machines, the project window (or functional equivalent) may help the user keep track of variables and the locations to which they are deployed. As noted above, the displayed variables are preferably selectable from the window, e.g., the project window, for inclusion in one or more programs, e.g., text-based programs and/or graphical programs. For example, in the case of graphical programs, the user may select the variable with a pointing device, and may drag and drop the variable onto the graphical program or block diagram, creating a reference to the variable in accordance with the current configuration. In other words, when a user drops a variable onto a block diagram, a usage of the variable may be created, where the usage of the variable has the appropriate implementation scripted underneath it. As described above, a user may reconfigure a variable such that its underlying implementation changes, in which case all of the usages of the variable are preferably updated accordingly. In some embodiments, if the user creates a reference, e.g., by dragging and dropping the variable from the source tree onto a block diagram, and the variable has not yet been instantiated or deployed, a new instance of the variable may automatically be created, e.g., on the local or host computer, or some default device specified by the user, where the new reference may access the new instance of the variable. Thus, various embodiments of the systems and methods described above may unite a number of different communications protocols and APIs under a single abstraction, e.g., variable abstraction, where users may create and/or configure (and re-configure) variables through a configuration dialog, and may select the communication characteristics they desire. Moreover, upon configuration of the variable, all deployments of the variable may be automatically updated, whether they are in the same program, in different programs on the same machine, or in different programs on different machines. | 20050118 | 20090922 | 20060323 | 79922.0 | G06F944 | 0 | SWEENEY, PATRICK E | VARIABLE ABSTRACTION | UNDISCOUNTED | 0 | ACCEPTED | G06F | 2,005 |
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11,037,706 | ACCEPTED | DUAL INLET PORT FOR INTERNAL COMBUSTION ENGINE | A system (10) and method for the induction of a fluid into the combustion chamber (15) of an internal combustion engine comprising a cylinder head (12) having at least one intake port (14) communicating with at least one combustion chamber (15) via a valve seat (22) disposed about the intake port (14), and at least one intake valve (16) provided with a valve head (20) having a valve face (21) engageable with the valve seat (22). The valve head (20) is connected to an elongate valve stem (18) that is mounted in the cylinder head (12) for controlling the intermittent flow of fluid from the intake port (14) to the combustion chamber (15). The system also includes first and second flow passages (30,32) that tangentially converge with the intake port (14) about the valve stem (18), preferably at the same acute angle relative to the valve stem and from substantially opposite directions, for setting in motion a balanced and complementary swirl of the fluid about the valve stem (18) in a clockwise or counterclockwise direction through intake port (14) towards combustion chamber (15). | 1. An inlet port induction system in an internal combustion engine, comprising (a) a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about said intake port; (b) at least one intake valve provided with a valve head having a valve face engageable with said valve seat, said valve head being connected to an elongate valve stem that is mounted in said cylinder head for controlling the intermittent flow of a first and second fluid from said intake port to said combustion chamber; and (c) a first flow passage for conducting said first fluid; and (d) a second flow passage for conducting said second fluid; said first and second flow passages tangentially converging with said intake port about said valve stem at acute angles relative to the longitudinal axis of the valve stem and at least 120 degrees apart from each other at their point of convergence with said intake port, for initiating a balanced and complementary flow of said first and second fluids about the valve stem in a clockwise or counterclockwise direction towards said combustion chamber. 2. (canceled) 3. The system according to claim 1 wherein the first and second flow passages tangentially converge with said intake port at substantially the same angle. 4. The system according to claim 1 wherein the first flow passage tangentially converges with said intake port at an angle less than the angle at which the second flow passage tangentially converges with said intake port. 5. (canceled) 6. The system according to claim 1 wherein the first and second flow passages are disposed substantially opposite to each other when viewed normal to the valve stem. 7. The system according to claim 1 wherein the first and second flow passages converge with said intake port at substantially the same height above the valve seat. 8. The system according to claim 1 wherein the first and second flow passages converge about said intake port at least about 0.6 cm above the valve seat. 9. The system according to claim 1 wherein the cylinder head of the internal combustion engine comprises a plurality of combustion chambers, each communicating with a first and second intake port and a corresponding first and second intake valve, wherein the first and second flow passages converging about the valve stem of the first intake valve causes the fluids flowing therethrough to be in a clockwise direction, and the first and second flow passages converging about the valve stem of the second intake valve causes the fluids flowing therethrough to be in a counter-clockwise direction, the flow of said fluids exiting said first and second intake ports being substantially complementary to each other as they enter the combustion chamber. 10. The system according to claim 9 wherein the cylinder head comprises four combustion chambers and a corresponding pair of intake ports and inlet valves per combustion chamber. 11. A method for the induction of a flow of fluid into the combustion chamber of an internal combustion engine, comprising (a) providing a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about said intake port; (b) providing at least one intake valve containing a valve head having a valve face engageable with said valve seat, said valve head being connected to an elongate valve stem that is mounted in said cylinder head for controlling the intermittent flow of a first and second fluid from said intake port to said combustion chamber; and (c) tangentially converging first and second flow passages with said intake port about the valve stem at acute angles relative to the longitudinal axis of the valve stem and at least 120 degrees apart from each other at their point of convergence with said intake port, for initiating a balanced and complementary flow of the first and second fluid about the valve stem in a clockwise or counterclockwise direction towards the combustion chamber when said first and second fluids are inducted through their respective first and second flow passages. 12. (canceled) 13. The method according to claim 11 wherein the first and second flow passages tangentially converge with said intake port at substantially the same angle. 14. The method according to claim 11 wherein the first flow passage tangentially converges about the valve stem at an angle less than the angle at which the second flow passage tangentially converges about the valve stem. 15. (canceled) 16. The method according to claim 11 wherein the first and second flow passages are disposed substantially opposite to each other when viewed normal to the valve stem. 17. The method according to claim 11 wherein the first and second flow passages converge with said intake port at substantially the same height above the valve seat. 18. The method according to claim 11 wherein the first and second flow passages converge with said intake port at least about 0.6 cm above the valve seat. 19. The method according to claim 11 wherein the cylinder head of the internal combustion engine comprises a plurality of combustion chambers, each communicating with a first and second intake port and a corresponding first and second intake valve, wherein the first and second flow passages about the valve stem of the first intake valve causes the fluids flowing therethrough to be in a clockwise direction, and the first and second flow passages about the valve stem of the second intake valve causes the fluid flowing therethrough to be in a counter-clockwise direction, the flow of said fluids exiting said first and second intake ports being complementary to each other as they enter the combustion chamber. 20. The method according to claim 19 wherein the cylinder head comprises four combustion chambers and a corresponding pair of intake ports and inlet valves per combustion chamber. 21. The method according to claim 11 wherein the first fluid is a fuel-air mixture. 22. The method according to claim 11 wherein the second fluid is air. 23. The method according to claim 11 wherein the fluid passing through the first flow passage comprises a fuel-air mixture and the fluid passing through the second flow passage comprises air. 24. The method according to claim 11 wherein the fluid flow passage having the smallest acute angle relative to the vertical axis of the combustion chamber conducts the flow of a fuel-air mixture for facilitating the deep filling of the combustion chamber, and the other flow passage conducts the flow of air to facilitate the scavenging of combustion residuals from the combustion chamber. 25. The method according to claim 11 wherein the cross-sectional areas of the first and second flow passages are substantially the same at the point of their convergence with said intake port. 26. An inlet port induction system for the passage of a fluid in an internal combustion engine, comprising (a) a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about said intake port; (b) at least one intake valve provided with a valve head having a valve face engageable with said valve seat, said valve head being connected to an elongate valve stem that is mounted in said cylinder head for controlling the intermittent flow of a first and second fluid from said intake port to said combustion chamber; and (c) a first and second flow passage for respectively conducting said first and second fluids therethrough, each flow passage tangentially converging with said intake port about said valve stem at an acute angle relative to the valve stem from substantially opposite directions and at least about 0.6 cm above said valve seat, for initiating a balanced and complementary flow of said fluid about said valve stem for establishing swirl of said fluids in said combustion chamber. 27. The system according to claim 26 wherein the first flow passage tangentially converges with said intake port at an angle less than the angle at which the second flow passage tangentially converges with said intake port. 28. The system according to claim 26 wherein the first and second flow passages are disposed at least 120 degrees apart from each other at their point of convergence with said intake port. 29. The system according to claim 26 wherein the first and second flow passages converge with said intake port at substantially the same height above said valve seat. 30. The system according to claim 26 wherein the cross-sectional areas of the first and second flow passages are substantially the same at the point of their convergence with the intake port. 31. An inlet port induction system in an internal combustion engine, comprising (a) a cylinder head having a first and second intake port communicating with a combustion chamber via a corresponding first and second valve seat respectively disposed about said first and second intake ports; (b) a first and second intake valve provided with a corresponding first and second a valve head, each having a corresponding first and second valve face engageable with its corresponding first and second valve seat, said first and second valve heads being connected to corresponding first and second elongate valve stems that are mounted in said cylinder head for controlling the intermittent flow of a first and second fluid from its corresponding first and second intake port to said combustion chamber; (c) said first intake port having first and second flow passages for respectively conducting said first and second fluids therethrough, said first and second flow passages of said first intake port tangentially converging with said first intake port about said first valve stem at acute angles relative to said first valve stem and at least 120 degrees apart from each other at their point of convergence with said first intake port, for initiating a balanced and complementary flow of said fluid about the first valve stem in a downward clockwise direction; and (d) said second intake port having first and second flow passages for respectively conducting said first and second fluids therethrough, said first and second flow passes of said second intake port tangentially converging with said second intake port about said second valve stem at acute angles relative to said second valve stem and at least 120 degrees apart from each other at their point of convergence with said second intake port, for initiating a balanced and complementary flow of said fluid about the second valve stem in a downward counter-clockwise direction; the flow of said first and second fluids exiting said first and second intake ports being substantially complementary to each other as they enter the combustion chamber. 32. (canceled) 33. The system according to claim 31 wherein the first and second flow passages tangentially converge with their respective first and second intake ports at substantially the same angle. 34. The system according to claim 31 wherein the first flow passages tangentially converge with said first intake ports at an angle less than the angle at which the second flow passages tangentially converge with said second intake ports. 35. (canceled) 36. The system according to claim 31 wherein the first and second flow passages for the first and second intake ports are disposed substantially opposite to each other when viewed normal to their corresponding valve stems. 37. The system according to claim 31 wherein the first and second flow passages converge with their corresponding first and second intake ports at substantially the same height above the first and second valve seats. 38. The system according to claim 31 wherein the first and second flow passages converge with their corresponding first and second intake ports at least about 0.6 cm above their first and second valve seats. 39. The system according to claim 31 wherein the cylinder head comprises four combustion chambers and corresponding first and second intake ports and inlet valves per combustion chamber. 40. The system according to claims 1, 26 or 31 wherein the first fluid is a fuel-air mixture. 41. The system according to claims 1, 26 or 31 wherein the second fluid is air. 42. The system according to claim 1, 26 or 31 wherein the fluid passing through the first flow passage comprises a mixture of fuel and air, and the fluid passing through the second flow passage comprises air. 43. The system according to claim 1, 26 or 31 wherein the flow passage having the smallest acute angle relative to the vertical axis of the combustion chamber conducts the flow of a fuel-air mixture for facilitating the deep filling of the combustion chamber, and the other flow passage conducts the flow of air to facilitate the scavenging of combustion residuals from the combustion chamber. 44. The system according to claim 1, 26 or 31 wherein the cross-sectional areas of the first and second fluid passages are substantially the same at the point of their convergence with their respective intake port. | BACKGROUND OF THE INVENTION 1. Field Of The Invention The invention relates to a system for improving fuel flow in internal combustion engines, and more particularly to a system and method for the induction of a fluid in an internal combustion engine that enhances valve cylinder filling and scavenging to provide for improved charge stratification and efficient combustion. 2. Background Obstacles to the efficient flow of fluid to the combustion chambers of internal combustion engines exist in even the best of current inlet porting systems. Generally, a fluid, such as a fuel/air mixture, that is introduced into an intake port must navigate around the valve stem of the intake valve before the fuel/air mixture enters the combustion chamber. Because the valve stem asserts itself in the middle of the fluid stream, vortices and fluid disruptions present themselves and serve as obstacles for impeding the flow of the fluid through the intake port. In addition, the fluid stream must redirect itself around the back face of the valve in order to fill the combustion chamber. Since the intake port is necessarily disposed at an angle to the valve and its valve stem in conventional engines, the back face of the valve will always deflect the fluid stream to one side of the intake port thereby rendering the opposite side of the intake port inaccessible as flow of fluid enters the combustion chamber. This problem is especially acute at lower valve openings, for example, in the critical overlap period that exists when combustion residuals from the previous combustion cycle are being swept out by incoming fluid flow. Inefficient mixing of fuel and air leads to incomplete or inefficient combustion in the engine's combustion chamber. 3. Related Art Various intake systems in multi-cylinder combustion engines have employed the use of dual inlet ports for controlling the passage of a fuel-air mixture to the combustion chamber. U.S. Pat. No. 4,469,063 issued Sep. 4, 1984 to Sugiura et al. discloses a complete inlet manifold and port system specifically designed for carbureted engines and for engines utilizing a single inlet valve. As illustrated in FIGS. 1 and 2, the intake port structure consists of a primary passage 18 that interfaces with the side wall of a secondary passage 20 in tangential relation to the combustion chamber, and is angled downwardly at a small acute angle relative to the plane of the intake valve seat 14. In order for the secondary passage to create a helical swirling motion of the fuel-air mixture in the combustion chamber, a flow deflector wall 22 is provided in the cylinder head which extends into the secondary passage 20 above and upstream of the intake valve 6. The resulting cross-flow and collision of the fuel-air mixture from each of the primary and secondary intake passages, and hence the destruction of the swirling effect, is avoided by providing a groove 26 in the inner surface 22u of secondary passage 20 which extends from the first outlet port 18b to the flow deflector wall 22 at a point adjacent to the valve seat 14. However, this design deliberately crosses the high-velocity, small (primary) inlet port, fuel-air mixture stream with that of the larger (secondary) inlet port so that the high-velocity stream redirects the larger stream by interference. The manner in which this is done interrupts any swirl created for the fluid and results in significant energy losses for the fluid stream entering the combustion chamber. U.S. Pat. No. 5,309,880 issued May 10, 1994 to Mazzella et al. discloses a dual intake port in a multi-cylinder reciprocating internal combustion engine (see FIGS. 1 and 2). The intake port consists of primary and secondary port passages, 22 and 24, respectively, that interface the stem of each intake valve of the engine. The dual port passages are parallel to each other and approach the intake port zone from a common direction at substantially right angles. While each of the primary and secondary port passages are oriented in tangential relationship to the valve stem 16, the flow pattern created for the fuel-air mixture passing through the passages (when the secondary throttle valve is open) is neither symmetrical nor in the form of a helical swirling action thereby resulting in energy loss to the fuel injection system. SUMMARY OF THE INVENTION In accordance with the invention, an induction system and method for the passage of a fluid, typically a mixture of fuel and air, in an internal combustion engine is provided. The system comprises a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about the intake port, and at least one intake valve provided with a valve head having a valve face engageable with the valve seat. The valve head is connected to an elongate valve stem that is mounted in the cylinder head for controlling the intermittent flow of fluid from the intake port to the combustion chamber. The system also includes a first and second flow passage that tangentially converges with the intake port about the valve stem, preferably at acute angles thereto and from substantially opposite directions, for setting in motion a balanced and complementary swirl of the fluid about the valve stem in a clockwise or counterclockwise direction towards said combustion chamber. In accordance with another aspect of the invention, a method for inducting a swirling flow of fluid into the combustion chamber of an internal combustion engine is provided. The method comprises providing a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about the intake port, and further providing at least one intake valve containing a valve head having a valve face engageable with the valve seat. The valve head is connected to an elongate valve stem that is mounted in the cylinder head for controlling the intermittent flow of fluid from the intake port to the combustion chamber. The method further comprises tangentially converging first and second flow passages with the intake port about the valve stem for setting in motion a balanced and complementary swirl of the fluid about the valve stem in a clockwise or counterclockwise direction towards the combustion chamber when the fluid is inducted through the first and second flow passages. In both the system and method for inducting a swirling flow of fluid into the combustion chamber, the first and second flow passages converge with the intake port at acute angles, preferably at the same acute angle relative to the valve stem and preferably at substantially the same height above the valve seat which should be at least 0.6 centimeters. However, the acute angles of the flow passages need not be the same in order to accommodate various cylinder head configurations. In order to facilitate a balanced and complementary flow of the fluid about the valve stem, the first and second passages are generally disposed at least 120 degrees apart from each other at their point of convergence with the intake port when viewed normal to the valve stem, and are preferably disposed substantially opposite to each other. If the velocities of the fluid passing through the first and second flow passages are substantially the same, the cross-sectional areas of the first and second fluid passages are preferably configured to be substantially the same at the point of their convergence with the intake port. For most spark ignition engine applications, the fluid passing through the first flow passage comprises a mixture of fuel and air, and the fluid passing through the second flow passage comprises air. The flow passage having the smallest acute angle relative to the vertical axis of the combustion chamber is preferred as the first flow passage in order to facilitate the deep filling of the combustion chamber with the mixture of fuel and air. The other flow passage having the greatest acute angle relative to the vertical axis of the combustion chamber will then be preferred as the second flow passage for conducting the flow of air therethrough to facilitate the scavenging of combustion residuals from the combustion chamber. In high performance vehicles such as those used in racing, a fuel-air mixture is typically utilized in both flow passages, and in diesel engine applications, the fluid flowing through both flow passages is air. With the induction system and method according to the invention herein, a balanced and complementary swirl of the fluid about the valve stem of the inlet valve is set in motion with minimal disruption and kinetic energy losses for the fluid. The induction of a fuel and air mixture into the combustion chamber of an internal combustion engine in this manner offers improved combustion for realizing higher horsepower and lower fuel consumption. BRIEF DESCRIPTION OF THE DRAWINGS A complete understanding of the present invention may be obtained by reference to the following specification when taken in conjunction with the accompanying drawings wherein certain preferred embodiments are illustrated and wherein like numerals refer to like parts throughout. FIG. 1 is an elevated cross-sectional plan view of the cylinder head of an internal combustion engine in accordance with an embodiment of the invention. FIG. 2 is an isometric perspective view of an isolated portion of the cylinder head illustrated in FIG. 1. FIG. 3 is a top plan view of the cylinder head illustrated in FIG. 2. FIG. 4 is an isometric perspective view of a cylinder head in accordance with another embodiment of the invention. FIG. 5 is a top plan view of an isolated portion of the cylinder head illustrated in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS THEREOF Throughout the following description, the preferred embodiments and examples are intended as exemplars rather than limitations on the apparatus of the present invention. The present invention provides a system and structure for the induction of a fluid, typically in the form of a fuel and air mixture, a mixture of fuel-air and air, or simply air, to the combustion chamber of an internal combustion engine, and specifically, a dual port induction structure for creating a balanced and complementary flow of fluid about the valve stem of an intake valve positioned within the intake port of a cylinder head to initiate a swirl of the fluid passing through the intake port into the engine's combustion chamber. The structure defined by the induction system utilizes acutely angled, convergent, tangential ducts with a common intake port for acquiring tangential fluid flow of the fluid about the valve stem. The tangential introduction of the fluid to a common intake port is designed to redirect the fluid flow around the face of the valve with a minimal loss of kinetic energy of the incoming fluid flow by reducing deflection losses normally incurred at the back side of the valve stem and valve face. By setting in motion a swirl of fluid about the valve stem and establishing a balanced and complementary swirl of the fluid as it enters the combustion chamber, the combustion characteristics of the fuel are enhanced resulting in improved engine performance. Referring to FIG. 1, and in accordance with a preferred embodiment of the invention, an induction system 10 configured for the induction of a fluid in an internal combustion engine is illustrated which comprises a cylinder head 12 containing an inlet port 14 that interfaces with a combustion chamber 15 for receiving the reciprocal movement of an intake valve 16. Intake valve 16 is mounted within cylinder head 12 and comprises a valve stem 18 connected to a valve head 20 having a valve face 21 thereon for engaging valve seat 22 located at the exit 14a of intake port 14. Valve stem 18 is axially disposed in cylinder head 12 for reciprocation therein to open and close the exposure of intake port 14 to combustion chamber 15. The reciprocation of intake valve 16 allows for the intermittent passage of a fuel-air mixture from the intake port into combustion chamber 15. An exhaust valve 24 is also mounted in cylinder head 12 for opening and closing the exposure of exhaust port 26 to combustion chamber 12, in cooperation with intake valve 16, to allow for the exit of combustion gases from combustion chamber 12 through exhaust duct 28. As shown in FIGS. 1 and 2, induction system 10 also includes a first inlet duct 30 and a second inlet duct 32 that tangentially converge with intake port 14 about valve stem 18. The tangential convergence of first and second inlet ducts 30,32 with intake port 14 about valve stem 18 occurs at a distance z above valve seat 22 thereby defining intake port 14 as a region for receiving and transporting the fluids emanating from inlet ducts 30,32 into combustion chamber 15. Accordingly, the distance z does not have to be substantial in height but sufficient to accommodate the initiation of a swirl of the fluid about valve stem 18 emanating from inlet ducts 30,32, and is therefore preferably at least 0.6 centimeters in height. The convergence of each of inlet ducts 30 and 32 with intake port 14, which preferably occurs at substantially the same height z above valve seat 22, is in a downward direction so as to funnel the flow of fluids passing through intake port 14 into combustion chamber 15. The downward directional configuration of inlet ducts 30,32 with intake port 14 is defined by acute angles and ε, respectively, relative to the longitudinal axis A of valve stem 18. Inasmuch as inlet duct 30 has a slight bend to it which is best shown in FIG. 1, for the purposes of the invention herein, axis B of inlet duct 30 and axis C of inlet duct 32 is determined at the point of the convergence of the ducts with each other about valve stem 18. In the embodiment shown in FIGS. 1 and 2, acute angles and ε are substantially the same so that a symmetrical swirl of both fluids is approached when they are introduced about valve stem 18 from respective inlet ducts 30,32. By tangentially directing the fluids about valve stem 18 at an acute angle to the valve stem's longitudinal axis A, a balanced and complementary flow of each of the fluids about the valve stem is set in motion in a downward direction towards combustion chamber 15. In accordance with the invention herein, the term balanced is used to describe the substantial utilization of the space surrounding valve stem 18 by each of the respective fluids, i.e., the space surrounding valve stem 18 from the point of convergence of inlet ducts 30,32 with intake port 14 about valve stem 18 to the exit 14a of intake port 14. The term complementary is used to describe the condition wherein the flow of fluids emanating from each of inlet ducts 30,32 do not substantially interfere with one another, and are not significantly impeded by the presence of valve stem 18. In other words, it refers to and characterizes the fluid flow condition about valve stem 18 wherein the swirl of each of the fluids through intake port 14 and entry into combustion chamber 15 is not taken out of substantial balance. The foregoing manner of flow is best exemplified and viewed by referring to FIG. 2, which for the purposes of clarity illustrates inlet ducts 30,32 and intake port 14 isolated from the remainder of the induction system 10 shown in FIG. 1. As fluid, e.g., a mixture of fuel and air, enters inlet duct 30, it is directed in a downward, tangential direction towards entry area 36 of the space surrounding valve stem 18. The path of the fuel-air mixture is represented by the series of arrows designated by reference number 34. Immediately after entering entry area 36, the fuel-air mixture begins its turn around valve stem 18 in a clockwise direction by following the final contours of inlet duct 30, and enters intake port 14 in the form of a downwardly spiraling swirl. Similarly, fluid, e.g., in the form of air, is introduced into inlet duct 32 and is directed in a downward direction to entry area 40 located at the opposite side of valve stem 18 and substantially opposite to entry area 36, as designated by the series of broken arrows 38. In each case, inlet ducts 30,32 are configured with intake port 14 to tangentially introduce their respective fluids around valve stem 18 in either a clockwise or counter-clockwise direction to minimize as much as possible any interference between the flows of the two fluids. As best shown in FIG. 3, inlet ducts 30,32 converge with intake port 14 about valve stem 18 from substantially opposite directions at an approach angle between tangential approach planes represented by lines FF and GG of approximately 180° when viewed normal to valve stem 18. Inlet ducts 30 and 32 are positioned apart from one another such that the fluid introduced from inlet duct 30 into entry area 36 is substantially opposite from the fluid introduced from inlet duct 32 into entry area 40 (see also FIG. 2). The purpose of tangentially introducing the fluids at opposite sides of valve stem 18 is to utilize the entire area surrounding the valve stem for the effective initiation of swirl for each of the fluids. In doing so, any resistance or flow obstruction that may be offered by the valve stem 18 is minimized, and each of the fluids entering intake port 14 from inlet ducts 30,32 will be balanced and complementary to each other, i.e., the momentum of flow of one fluid will not distort or substantially affect the momentum of flow of the other. Flow symmetry of both fluids is therefore optimally approached when inlet ducts 30,32 converge with intake port 14 at substantially the same height above valve seat 22 from substantially opposite directions and at substantially the same acute angle relative to valve stem 18. It will be appreciated that a given cylinder head configuration among the multiplicity of designs that are currently available may not allow inlet ducts 30 and 32 to converge about valve stem 18 from substantially opposite directions. However, if the approach angle is less than 120°, then the complementation of the flow of both fluids begins to be compromised. Fluid flowing from inlet duct 30 has the possibility of impeding or interfering with the momentum of the flow of fluid from inlet duct 32, and vice-versa. The result is the inability of the fluids to remain balanced and complementary with each other for setting in motion the desired swirl about the valve stem 18. If this happens to any substantial degree, then any flow symmetry established for the fluids about valve stem 18 will be compromised. While it is possible for inlet ducts 30,32 to function with an approach angle of less than 120 degrees, it is preferred that approach angle for the disposition of inlet ducts 30 and 32 relative to each other be at least 120°. For most applications of the induction system 10 to a given cylinder head configuration, the velocity of the fluids flowing through inlet ducts 30,32 will generally be substantially the same over a broad range of engine load conditions, or if different, the velocities will be such that balance and complementation of the fluids will not be significantly altered. Accordingly, optimal flow symmetry for each of the fluids about valve stem 18 is best approached by configuring the cross-sectional areas of the inlet ducts to be substantially the same at their point of convergence with intake port 14. If the velocities of the respective fluids introduced to inlet ducts 30 and 32 are substantially different, then the cross-sectional areas of one or both of the inlet ducts 30,32 can be adjusted to promote a balanced and complementary flow of the respective fluids about valve stem 18. Several advantages are obtained with the induction system according to the invention. In a single porting system for inducting a fluid such as a fuel-air mixture into a combustion chamber, the disruption and energy losses imparted to the fluid flow is caused by the fluid's contact with the walls of the inlet port, the flow disruptive vortices that normally occur on the blind side of the valve stem, and the subsequent impact with the corresponding valve head. These kinetic energy losses are avoided or at least substantially minimized by the tangential convergence of dual ducts about valve stem 18 since the fluids introduced into inlet ducts 30 and 32, respectively, do not impinge on the valve stem 18, and less so on the valve head 20, for entry into the combustion chamber. Because a balanced swirl of the respective fluids about the valve stem is set in motion, the inlet duct fluids are enabled to flow past valve stem 18 and valve head 20 with minimal disruption and energy losses. The fuel-air mixture introduced to entry area 36 from inlet duct 30 does not interfere with in any substantial way the air being introduced to entry area 40 by inlet duct 32. The swirl that is set in motion for each of the fluids therefore complement each for establishing a symmetry of flow during their passage through intake port 14 into combustion chamber 15. Another significant advantage of the induction system according to the invention lies in the improved downdraft and cross-flow capabilities offered by the downward tangential convergence of inlet ducts 30,32 with intake port 14 about the valve stem. Referring once again to FIG. 1, the respective axes A and E of valve stem 18 and exhaust valve 24 are acutely angled relative to the axis D of combustion chamber 15 which is typical of hemispherical, pent roof, and wedge cylinder head type engines. If a fuel-air mixture is introduced into inlet duct 30, swirl of the fuel-air mixture will be initiated about valve stem 18 as it enters entry area 36 (see FIG. 2), and will fully develop as it passes through exit 14a of intake port 14 and the outside diameter of valve face 21 when intake valve 16 is fully extended into combustion chamber 15. Once the fuel-air mixture exits intake port 14, its swirl is directed towards the deepest part of combustion chamber 15 by virtue of the disposition of inlet duct 30 relative to axis D of combustion chamber 15. Because the loss of kinetic energy of the fuel-air mixture flow within intake port 14 is minimized, as discussed above, cylinder filling is enhanced by the attendant increase in momentum of the fuel-air mixture charge. Stated another way, a natural assistance to the cylinder filling process is created within intake port 14 because fluid resistance in the form of frictional losses and vortices are overcome by the tangential flow of the fluid fuel about the valve stem. The resulting swirl that is initiated about the valve stem causes a corresponding increase in the inertial charge of the fluid fuel. Consequently, inlet duct 30, by virtue of its axial disposition to the vertical axis D of combustion chamber 15, renders it as the choice for the passage of a fuel-air mixture into the deeper part of the combustion chamber. The increase in fluid energy developed within intake port 14 is therefore efficiently utilized to facilitate cylinder filling. By applying a similar analysis, and again referring to FIG. 1, the axis C of inlet duct 32 is disposed in relationship to axis D of combustion chamber 15 at a much greater (or less acute) angle than that of inlet duct 30. If air is introduced into inlet duct 32, an air swirl will be initiated about valve stem 18 within intake port 14 as the air enters entry area 40 (FIG. 2). Like the fuel-air mixture swirl entering combustion chamber 15, the air swirl fully develops as it passes through exit 14a of intake port 14 and the outside diameter of valve face 21 (when intake valve 16 is fully extended into combustion chamber 15). However, unlike the direction that the fuel-air mixture takes, as the air exits intake port 14 past valve head 20, its swirl is directed across combustion chamber 15, towards exhaust valve 24 and exhaust port 26, for enhancing the removal or “sweeping out” of residual gases remaining from the previous combustion cycle, resulting in less unburned fuel being drawn out exhaust port 26. By virtue of its axial disposition to axis D of combustion chamber 15 (at a greater acute angle than inlet duct 30), inlet duct 32 serves as a “side-draft” or “cross-flow” duct for the introduction and passage of air into combustion chamber 15. Inasmuch as the momentum of the airflow passing through intake port 14 and valve seat 21 will be greater as a result of the minimization of the kinetic energy losses discussed above, a shorter period of time will be necessary for “blowing down” or “scavenging” the residuals of the previous combustion cycle. Stratification of the fuel-air mixture and air fluids is also enhanced by the respective directions that each of them takes into combustion chamber 15, and propagation of the flame front originating from the spark plug (not shown) is improved. The improved air flow from inlet duct 32 through intake port 14 also allows for the configuration of smaller inlet valves and a more compact combustion chamber, which in turn allows for increased squish area in the combustion chamber 15. As is generally known, swirl action and large squish area are both well-established aids to a more complete combustion of the fuel delivered to the combustion chamber. It will be appreciated that angles and ε at which respective inlet ducts 30 and 32 are disposed relative to valve stem 18 can be varied depending on the configuration of the cylinder head and the disposition of inlet valve 20 relative to combustion chamber 15. For example, once again referring to FIG. 1, if the cylinder head configuration dictates that valve head 20 of inlet valve 16 is substantially perpendicular to combustion chamber 15, i.e., if axis A of valve stem 18 approaches a very acute angle that renders it substantially parallel with, or near parallel to, the vertical axis D of combustion chamber 15, then the disposition of inlet ducts 30 and 32 relative to valve stem 18 can be adjusted to comport with and ε angles that provide optimum deep filling and cross-flow characteristics for the fluids passing from respective inlet ducts 30,32 into combustion chamber 15. In this case, the value of will be less than the value of ε, and inlet duct 30 will be disposed at more of an acute angle to valve stem 18 than inlet duct 32. Because of the disposition of inlet duct 30 relative to axis D of combustion chamber 15, it, rather than inlet duct 32, becomes the choice for transporting the fuel-air mixture for enhancing the deep filling of combustion chamber 15. The axial disposition of inlet duct 32 with axis D of combustion chamber 15 enhances the removal of residual gases remaining from the previous combustion cycle. Furthermore, by virtue of the tangential convergence of each of the fluids about valve stem 18, their balanced and complementary flow properties established within intake port 14 are substantially maintained. The design variable for adjusting the angles at which inlet ducts 30,32 converge about valve stem 18 offers a wide degree of flexibility for not only improving and adjusting fluid flow about the intake valve stem in a way that approaches symmetry for the two fluids, but also lends itself for optimizing deep cylinder filling and cross-flow properties within the combustion chamber. The induction system according to the invention can therefore be incorporated with a variety of cylinder head configurations since it combines the benefits of both “crossflow” and “downdraft” cylinder heads into one design, along with better swirl combustion than existing practices. In accordance with another aspect of the invention, FIG. 4 illustrates the application of the induction system 10 in FIG. 1 to a standard, 40 degree, four-valve per cylinder, cylinder head 50. Typically, cylinder head 50 comprises four combustion chambers and a corresponding pair of intake ports and inlet valves per combustion chamber for use in an automotive internal combustion engine. The relevant features of cylinder head 50 according to the invention comprise a pair of intake valves 52 and 54 and a corresponding pair of exhaust valves 56 and 58 having corresponding valve stems 52s,54s,56s,58s. The valve heads (not shown) of intake valves 52 and 54, and the respective valve heads 56h and 58h of exhaust valves 56, 58 interface combustion chamber 15 (as outlined in bold dashed lines) in the same manner illustrated for valve heads 20 and 24h in FIG. 1. Tangentially converging about valve stem 52s in a downward direction with a corresponding intake port 52p is inlet duct 62 and inlet duct 64. In similar fashion, inlet duct 66 and inlet duct 68 tangentially converge about valve stem 54s with its corresponding intake port 54p. With the exception explained below, the convergence of inlet ducts 62,66 and 66,68 with their corresponding intake ports 52p,54p about their respective valve stems 52s,54s is at the respective corresponding angles and ε shown in FIG. 1. It will be understood that these angles can vary for inlet ducts 62,64 and 66,68 depending on the cylinder head configuration for a given internal combustion engine. As shown in FIG. 5, each of inlet ducts 62,64 and 66,68 approach their respective valve stems 52s,54s from substantially opposite directions, i.e., at about 180° apart from each other as defined by approach angles and between tangential approach planes represented by respective lines JJ,KK and J′J′,K′K′. The respective approach angles and can vary depending on the given configuration for the cylinder head of the engine. The value for approach angles and is preferred to be at least 120° for the reasons that have been explained hereinbefore. Inlet ducts 64 and 68 are joined upstream of their convergence with their respective intake ports thereby defining common duct 70, and share the passage of the same fluid, typically air. The bifurcation of common duct 70 into inlet ducts 64 and 68 is such that inlet ducts 64,68 have substantially the same cross-sectional area for dividing the flow of air equally to their respective intake ports 52p,54p. In the illustration shown in FIGS. 4 and 5, all of the inlet ducts have substantially the same cross-sectional area for promoting a balanced and complementary flow of the fluids about their respective valve stems and into their corresponding intake ports. As best illustrated in FIG. 5 which shows the convergence of the inlet ducts about their respective valve stems when viewed normal to the valve stems, the convergence of inlet ducts 62,64 about valve stem 52s is such that the fluids entering intake port 52p are in a clockwise direction. Conversely, the fluids flowing through inlet ducts 66,68 converge about valve stem 54s and enter intake port 54p in a counter-clockwise direction. As a result, the swirl pattern of the fluid flows emerging from intake ports 52p and 54p into combustion chamber 15 is complementary to the other, thereby assisting in cylinder filling and exhaust scavenging of the respective fluids. The use of tangentially converging inlet ducts about the intake valve stems of a cylinder head combines the benefits of both “downdraft” and “cross flow” cylinder heads into one design and simultaneously provides improved swirl and combustion over existing practices. The improved cylinder filling afforded by the induction system according to the invention therefore allows for the design of a smaller and lighter engine since performance will be improved across the entire RPM range of the engine. Also, the improved low-end torque allows for the use of a small displacement engine in most applications. With the vehicle in a relatively constant RPM mode, as experienced in highway driving, the same engine can be geared for relatively low engine speeds. The result is a reduction of displacement per mile accompanied by a reduction in pumping and frictional losses and an improvement in both gasoline mileage and a reduction of pollution. When higher power is needed, the added inertial charge to the fluid caused by the improved flow characteristics of the induction system herein allows the engine to “breathe” more freely at higher RPM. The improvements in combustion and charge stratification also translate to greater power, higher efficiency, and lower pollution. The induction system according to the invention herein is applicable to any gasoline or diesel internal combustion engine and is beneficially used with any type of cylinder head arrangement. Since other modifications and changes may be varied to fit the particular operating requirements and environments of the invention, which will be apparent to those skilled in the art, the invention is not considered to be limited to the embodiments chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope thereof. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field Of The Invention The invention relates to a system for improving fuel flow in internal combustion engines, and more particularly to a system and method for the induction of a fluid in an internal combustion engine that enhances valve cylinder filling and scavenging to provide for improved charge stratification and efficient combustion. 2. Background Obstacles to the efficient flow of fluid to the combustion chambers of internal combustion engines exist in even the best of current inlet porting systems. Generally, a fluid, such as a fuel/air mixture, that is introduced into an intake port must navigate around the valve stem of the intake valve before the fuel/air mixture enters the combustion chamber. Because the valve stem asserts itself in the middle of the fluid stream, vortices and fluid disruptions present themselves and serve as obstacles for impeding the flow of the fluid through the intake port. In addition, the fluid stream must redirect itself around the back face of the valve in order to fill the combustion chamber. Since the intake port is necessarily disposed at an angle to the valve and its valve stem in conventional engines, the back face of the valve will always deflect the fluid stream to one side of the intake port thereby rendering the opposite side of the intake port inaccessible as flow of fluid enters the combustion chamber. This problem is especially acute at lower valve openings, for example, in the critical overlap period that exists when combustion residuals from the previous combustion cycle are being swept out by incoming fluid flow. Inefficient mixing of fuel and air leads to incomplete or inefficient combustion in the engine's combustion chamber. 3. Related Art Various intake systems in multi-cylinder combustion engines have employed the use of dual inlet ports for controlling the passage of a fuel-air mixture to the combustion chamber. U.S. Pat. No. 4,469,063 issued Sep. 4, 1984 to Sugiura et al. discloses a complete inlet manifold and port system specifically designed for carbureted engines and for engines utilizing a single inlet valve. As illustrated in FIGS. 1 and 2 , the intake port structure consists of a primary passage 18 that interfaces with the side wall of a secondary passage 20 in tangential relation to the combustion chamber, and is angled downwardly at a small acute angle relative to the plane of the intake valve seat 14 . In order for the secondary passage to create a helical swirling motion of the fuel-air mixture in the combustion chamber, a flow deflector wall 22 is provided in the cylinder head which extends into the secondary passage 20 above and upstream of the intake valve 6 . The resulting cross-flow and collision of the fuel-air mixture from each of the primary and secondary intake passages, and hence the destruction of the swirling effect, is avoided by providing a groove 26 in the inner surface 22 u of secondary passage 20 which extends from the first outlet port 18 b to the flow deflector wall 22 at a point adjacent to the valve seat 14 . However, this design deliberately crosses the high-velocity, small (primary) inlet port, fuel-air mixture stream with that of the larger (secondary) inlet port so that the high-velocity stream redirects the larger stream by interference. The manner in which this is done interrupts any swirl created for the fluid and results in significant energy losses for the fluid stream entering the combustion chamber. U.S. Pat. No. 5,309,880 issued May 10, 1994 to Mazzella et al. discloses a dual intake port in a multi-cylinder reciprocating internal combustion engine (see FIGS. 1 and 2 ). The intake port consists of primary and secondary port passages, 22 and 24 , respectively, that interface the stem of each intake valve of the engine. The dual port passages are parallel to each other and approach the intake port zone from a common direction at substantially right angles. While each of the primary and secondary port passages are oriented in tangential relationship to the valve stem 16 , the flow pattern created for the fuel-air mixture passing through the passages (when the secondary throttle valve is open) is neither symmetrical nor in the form of a helical swirling action thereby resulting in energy loss to the fuel injection system. | <SOH> SUMMARY OF THE INVENTION <EOH>In accordance with the invention, an induction system and method for the passage of a fluid, typically a mixture of fuel and air, in an internal combustion engine is provided. The system comprises a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about the intake port, and at least one intake valve provided with a valve head having a valve face engageable with the valve seat. The valve head is connected to an elongate valve stem that is mounted in the cylinder head for controlling the intermittent flow of fluid from the intake port to the combustion chamber. The system also includes a first and second flow passage that tangentially converges with the intake port about the valve stem, preferably at acute angles thereto and from substantially opposite directions, for setting in motion a balanced and complementary swirl of the fluid about the valve stem in a clockwise or counterclockwise direction towards said combustion chamber. In accordance with another aspect of the invention, a method for inducting a swirling flow of fluid into the combustion chamber of an internal combustion engine is provided. The method comprises providing a cylinder head having at least one intake port communicating with at least one combustion chamber via a valve seat disposed about the intake port, and further providing at least one intake valve containing a valve head having a valve face engageable with the valve seat. The valve head is connected to an elongate valve stem that is mounted in the cylinder head for controlling the intermittent flow of fluid from the intake port to the combustion chamber. The method further comprises tangentially converging first and second flow passages with the intake port about the valve stem for setting in motion a balanced and complementary swirl of the fluid about the valve stem in a clockwise or counterclockwise direction towards the combustion chamber when the fluid is inducted through the first and second flow passages. In both the system and method for inducting a swirling flow of fluid into the combustion chamber, the first and second flow passages converge with the intake port at acute angles, preferably at the same acute angle relative to the valve stem and preferably at substantially the same height above the valve seat which should be at least 0.6 centimeters. However, the acute angles of the flow passages need not be the same in order to accommodate various cylinder head configurations. In order to facilitate a balanced and complementary flow of the fluid about the valve stem, the first and second passages are generally disposed at least 120 degrees apart from each other at their point of convergence with the intake port when viewed normal to the valve stem, and are preferably disposed substantially opposite to each other. If the velocities of the fluid passing through the first and second flow passages are substantially the same, the cross-sectional areas of the first and second fluid passages are preferably configured to be substantially the same at the point of their convergence with the intake port. For most spark ignition engine applications, the fluid passing through the first flow passage comprises a mixture of fuel and air, and the fluid passing through the second flow passage comprises air. The flow passage having the smallest acute angle relative to the vertical axis of the combustion chamber is preferred as the first flow passage in order to facilitate the deep filling of the combustion chamber with the mixture of fuel and air. The other flow passage having the greatest acute angle relative to the vertical axis of the combustion chamber will then be preferred as the second flow passage for conducting the flow of air therethrough to facilitate the scavenging of combustion residuals from the combustion chamber. In high performance vehicles such as those used in racing, a fuel-air mixture is typically utilized in both flow passages, and in diesel engine applications, the fluid flowing through both flow passages is air. With the induction system and method according to the invention herein, a balanced and complementary swirl of the fluid about the valve stem of the inlet valve is set in motion with minimal disruption and kinetic energy losses for the fluid. The induction of a fuel and air mixture into the combustion chamber of an internal combustion engine in this manner offers improved combustion for realizing higher horsepower and lower fuel consumption. | 20050117 | 20060718 | 20060720 | 95425.0 | F02B3100 | 1 | KWON, JOHN | DUAL INLET PORT FOR INTERNAL COMBUSTION ENGINE | MICRO | 0 | ACCEPTED | F02B | 2,005 |
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11,037,738 | ACCEPTED | Reproducing apparatus | A reproducing apparatus includes a reproducing unit that reproduces a video data sequence including video data of a plurality of pictures from a recording medium. The video data sequence is encoded by a coding method in which the amount of data per picture changes from one picture to another. The reproducing apparatus further includes an error correcting unit that corrects the reproduced video data sequence for an error, and a control unit that substitutes data of a picture including an error that is uncorrectable by the error correcting unit with predetermined encoded data so as to output the same image as a picture immediately previous to the picture including the uncorrectable error when the video data sequence is decoded. | 1. A reproducing apparatus comprising: reproducing means for reproducing a video data sequence including video data of a plurality of pictures from a recording medium, the video data sequence being encoded by a coding method in which an amount of data per picture changes from one picture to another picture; error correcting means for correcting an error in the video data sequence reproduced by the reproducing means; and control means for performing substitution on the video data sequence so that data of a picture including an error that is uncorrectable by the error correcting means is substituted with predetermined encoded data so as to output the same image as a picture immediately previous to the picture including the error that is uncorrectable when the video data sequence is decoded. 2. A reproducing apparatus according to claim 1, wherein the video data sequence is encoded by selectively using picture-by-picture intra-picture coding using only data within the same picture and inter-picture coding encoding difference data from a reference picture, and the predetermined encoded data comprises coded data indicating that difference data from the immediately previous picture is zero. 3. A reproducing apparatus according to claim 1, further comprising decoding means for decoding the video data sequence that is subjected to the substitution by the control means. 4. A reproducing apparatus according to claim 1, further comprising detecting means for detecting system data from the video data sequence reproduced by the reproducing means, the system data including time stamp information for use in decoding the video data sequence, wherein the video data sequence is error correction coded in units of a predetermined amount of video data of the video data sequence, and the control means determines the number of pictures to be substituted with the predetermined encoded data based on the time stamp information of the system data detected by the detecting means before and after the predetermined amount of video data including the uncorrectable error. 5. A reproducing apparatus according to claim 4, wherein the system data is added every predetermined number of pictures of the video data, and the control means substitutes video data between the system data detected before and after the predetermined amount of video data including the uncorrectable error with the predetermined encoded data. 6. A reproducing apparatus according to claim 5, wherein the control means substitutes the video data between the system data detected before and after the predetermined amount of video data including the uncorrectable error with the predetermined encoded data corresponding to the determined number of pictures and dummy data indicating the difference between the amount of the video data between the system data detected before and after the predetermined amount of video data including the uncorrectable error and the amount of the predetermined encoded data corresponding to the determined number of pictures. 7. A reproducing apparatus according to claim 6, wherein the system data further includes buffer information indicating the amount of data stored in a buffer memory for use in decoding the video data sequence, and the control means determines the amount of video data between the system data detected before and after the predetermined amount of video data including the uncorrectable error using the time stamp information and the buffer information of the system data detected before and after the predetermined amount of video data including the uncorrectable error. 8. A reproducing apparatus according to claim 4, wherein the video data sequence is encoded by selectively using picture-by-picture intra-picture coding using only data within the same picture and inter-picture coding encoding difference data from a reference picture, an intra-picture-coded picture is selected every n pictures, and the control means determines the number of pictures to be substituted with the predetermined encoded data based on the time stamp information of the system data detected immediately before the predetermined amount of video data including the uncorrectable error and the time stamp information of the system data in the intra-picture-coded picture after the predetermined amount of video data including the uncorrectable error. 9. A reproducing apparatus according to claim 4, wherein the predetermined amount of video data is related to a data arrangement of the video data sequence on the recording medium. 10. A reproducing apparatus according to claim 1, further comprising external outputting means for outputting the encoded video data sequence that is subjected to the substitution by the control means to outside of the reproducing apparatus. 11. A reproducing apparatus according to claim 1, wherein the video data sequence is recorded in multiple tracks formed on the recording medium, and the error correcting means corrects the video data sequence for an error in units of a predetermined number of tracks in which the video data sequence is recorded. 12. A reproducing apparatus comprising: reproducing means for reproducing a video data sequence including system data and video data that is encoded using a predictive coding method in which the amount of data per picture changes from one picture to another from multiple tracks formed on a recording medium, the system data being multiplexed with the video data in units of a predetermined number of pictures so that at least the encoded video data can be decoded, the system data including time stamp information for use in decoding the video data; error correcting means for correcting an error in the video data sequence reproduced by the reproducing means in units of a predetermined number of tracks from which the video data sequence is reproduced; and control means for determining the number of pictures of the video data between the system data before and after a picture including an error that is uncorrectable by the error correcting means, and substituting the video data of the determined number of pictures with predetermined encoded data so as to output the same image as a picture immediately previous to the picture including the uncorrectable error when the video data sequence is decoded. 13. A reproducing apparatus comprising: reproducing means for reproducing a video data sequence, from a recording medium, including system data and video data that is encoded using a predictive coding method in which the amount of data per picture changes from one picture to another, the system data being multiplexed with video data in units of a predetermined number of pictures so that at least the encoded video data can be decoded, the system data including buffer information indicating the amount of data stored in a buffer memory for use in decoding the video data; error correcting means for correcting an error in the video data sequence reproduced by the reproducing means; and control means for determining the amount of video data between first system data and second system data using buffer information in the first system data and buffer information in the second system data, and substituting the determined amount of video data with predetermined encoded data, the first system data being reproduced immediately before a picture including an error that is uncorrectable by the error correcting means, the second system data being reproduced after the picture including the uncorrectable error. 14. A reproducing apparatus according to claim 13, wherein the video data is encoded by selectively using picture-by-picture intra-picture coding using only data within the same picture and inter-picture coding encoding difference data from a reference picture, and the predetermined encoded data includes coded data indicating that difference data from the immediately previous picture is zero, and dummy data corresponding to the determined amount of video data. 15. A reproducing apparatus according to claim 13, wherein the video data is encoded by selectively using picture-by-picture intra-picture coding using only data within the same picture and inter-picture coding encoding difference data from a reference picture, an intra-picture-coded picture is selected every n pictures, and the system data is multiplexed immediately before at least the intra-picture-coded picture. 16. A signal processing apparatus comprising: inputting means for inputting a video data sequence including MPEG-encoded video data; error correcting means for correcting an error in the input video data sequence; and control means for substituting video data in a group of pictures including a picture including an error that is uncorrectable by the error correcting means with Copy-Picture data complying with MPEG. 17. A signal processing apparatus according to claim 16, wherein the control means substitutes all video data from the picture including the uncorrectable error to a next group of pictures with the Copy-Picture data. 18. A signal processing apparatus according to claim 16, wherein system data including time stamp information for use in decoding the video data is multiplexed every n pictures including the head of a group of pictures in the video data, and the control means further determines the number of pictures of the video data between first system data and second system data using time stamp information in the first system data and time stamp information in the second system data, and substitutes the video data between the first system data and the second system data with the Copy-Picture data corresponding to the determined number of pictures, the first system data being input immediately before the picture including the uncorrectable error, the second system data being multiplexed at the head of a group of pictures immediately after the picture including the uncorrectable error. 19. A signal processing apparatus according to claim 18, wherein the control means substitutes the video data between the first system data and the second system data with an amount of stuffing data corresponding to the difference between the amount of data between the first system data and the second system data in the video data sequence and the amount of Copy-Picture data corresponding to the determined number of pictures. 20. A signal processing apparatus according to claim 19, wherein the system data further includes VBV_Delay information about a data storage time of a video buffering verifier buffer that is specified by MPEG, and the control means further determines the amount of data between the first system data and the second system data using the VBV_Delay information of the first system data and the VBV_Delay information of the second system data. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing apparatus, and more specifically to processing of error data in encoded image data. 2. Description of the Related Art An apparatus for encoding video data using an encoding technique, such as MPEG (moving picture expert group), and recording and reproducing the encoded data is disclosed in, for example, Japanese Patent Laid-Open No. 2003-46944 (corresponding U.S. Published Application No. 2003/26590). In this recording and reproducing apparatus, if reproduced encoded data is missing, the missing data is substituted with encoded data of a specific color, such as black or gray. However, this apparatus outputs a black or gray picture for missing data, and gives an undesirable image to the user. Moreover, if black or gray data is merely inserted in an encoded stream, the resulting stream is not verified with the buffer model (VBV (video buffering verifier) buffer) that is specified by MPEG, and a decoder may cause decoding failure due to underflow or overflow of data stored in a buffer memory. SUMMARY OF THE INVENTION In order to overcome the foregoing problems, the present invention provides a system for preventing decoding failure if missing data, such as an error, occurs in an encoded stream to give a desirable reproduced screen. In an aspect of the present invention, a reproducing apparatus includes a reproducing unit that reproduces a video data sequence including video data of a plurality of pictures from a recording medium, the video data sequence being encoded by a coding method in which the amount of data per picture changes from one picture to another, an error correcting unit that corrects the video data sequence reproduced by the reproducing unit for an error, and a control unit that performs substitution on the video data sequence so that data of a picture including an error that is uncorrectable by the error correcting unit is substituted with predetermined encoded data so as to output the same image as a picture immediately previous to the picture including the uncorrectable error when the video data sequence is decoded. Further features and advantages of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a reproducing apparatus according to the present invention. FIG. 2 is a diagram showing the track format of a tape. FIG. 3 is a diagram showing the format of data recorded in each track. FIG. 4 is a flowchart showing a reproducing process. FIG. 5 is a flowchart showing an error data substitution process. DESCRIPTION OF THE EMBODIMENTS Embodiments of the present invention will be described. FIG. 1 is a block diagram of a reproducing apparatus 100 according to the present invention. The apparatus 100 shown in FIG. 1 reproduces an MPEG-encoded video stream from multiple tracks on a tape T. In MPEG, a data stream is encoded using the following three picture coding types frame-by-frame in predetermined order: I picture (intra-coded picture) coding using only image data within the same frame, P picture (predictive-coded picture) coding with motion compensation based on a preceding frame picture, and B picture (bi-directionally-predictive-coded picture) coding with motion compensation using the image data of the preceding and succeeding frames. In MPEG, a data stream is encoded in units of a predetermined number of frames starting from a given I picture to the next I picture, called a GOP (Group Of Pictures). I pictures are coded using only image data within the same frame. In P and B pictures, difference data from a reference frame is encoded, and the amount of encoded data changes from one frame to another. In the present embodiment, image data is encoded and recorded so as to have substantially a predetermined data rate of several Mbps. In FIG. 1, a reproducing unit 101 reproduces the recorded encoded image data, and outputs the reproduced image data to an error correcting unit 102. The error correcting unit 102 decodes the reproduced data according to error correction coding that the recorded image data is subjected to, and corrects for a transmission error in the reproduced data. If the reproduced data contains an uncorrectable error, the error correcting unit 102 informs a control unit 107 of the uncorrectable error. FIG. 2 illustrates a format of the data recorded in the tape T. As shown in FIG. 2, in the present embodiment, data is interleaved in units of 16 tracks, and the interleaved data is subjected to error correction coding to add an outer code. A unit of 16 tracks is referred to as an “ECC unit”. The error correcting unit 102 performs error correction decoding in units of ECC units. In this case, an uncorrectable error can occur in units of ECC units, and correct reproduced data may be missing. In the present embodiment, in addition to the MPEG-encoded image and audio data, system data is inserted every predetermined number of frames. The system data is data for editing the encoded image and audio data recorded in the tape T, and includes a DTS (decoding time stamp) and VBV_Delay value of the encoded data. In the present embodiment, a GOP consists of 15 frames in order of I, B, B, P, B, B, P, B, B, P, B, B, P, B, B pictures, and system data is inserted every 3 frames. In one GOP, therefore, system data is multiplexed before the I picture and the P pictures. The DTS is a time stamp for synchronizing MPEG data when decoded. When the value of a decoder counter that counts a reference time coincides with the value of the DTS, MPEG data is actually decoded. In MPEG-2, the value of a counter that counts a 27-MHz system clock is used as a reference time. The VBV_Delay value indicates the time for which encoded data of one frame resides in a VBV buffer that is specified by MPEG when decoded. FIG. 3 illustrates the structure of data recorded in each track shown in FIG. 2. As shown in FIG. 3, data recorded in one track consists of 139 sync blocks 0 to 138. Each sync block is constituted by Sync, ID0, ID1, ID2, encoded data or outer parity, and inner parity. ID0 to ID2 include track pair number information indicating the track position in one ECC block, and sync block number information of one track. The outer parity shown in FIG. 3 is added by calculation to interleaved data of 16 tracks. The error correcting unit 102 performs error correction decoding in units of 16 tracks using the outer parity and the inner parity. The data corrected by the error correcting unit 102 is written in a stream buffer 103. The stream buffer 103 has a storage capacity more than the amount of data specified by MPEG. A buffer managing unit 106 manages writing and reading of data to and from the stream buffer 103 and other processing under the control of a control unit 107. The encoded data stored in the stream buffer 103 is sent to a decoder 104 at a timing determined based on the DTS, and is then decoded. The decoded image and audio data is output to an external monitor or the like from an output unit 105. The encoded data stored in the stream buffer 103 is also output to a digital interface (DIF) 108. The DIF 108 outputs the MPEG stream data output from the stream buffer 103 to an external decoder or the like via a transmission path according to a digital interface standard, such as IEEE 1394. Processing of error data in reproduced data by the reproducing apparatus 100 will now be described. In the following description, encoded data is recorded in the manner shown in FIG. 2, and the data in the ECC unit 2 contains an uncorrectable error. FIG. 4 is a flowchart showing uncorrectable-error control performed by the control unit 107. In FIG. 4, first, it is determined whether or not a reproduced ECC unit includes system data (step S401). In FIG. 2, each of the ECC units 1 to 3 includes system data. In the present embodiment, as described above, image data is encoded so that the amount of data changes depending upon the frame, and therefore system data is not always contained in an ECC unit. If no error detection flag is output from the error correcting unit 102 and if an ECC unit reproduced by the buffer managing unit 106 includes system data, the control unit 107 determines whether or not an error flag indicating the presence of error data in any preceding reproduced ECC unit is set (step S402). If the error flag is not set, it is determined that no preceding ECC unit data containing an uncorrectable error exists or a substitution procedure described below has been performed, and the reproduced system data is stored in a system data backup memory of the buffer managing unit 106 (step S409). The backup memory of the buffer managing unit 106 includes a first memory area for storing the system data detected immediately before an ECC unit containing an uncorrectable error, and a second memory area for storing the system data multiplexed at the head of the GOP reproduced immediately after an ECC unit containing an error. If it is determined in step S402 that the error flag is not set, the first memory area is overwritten each time system data is detected, and the detected system data is stored in the first memory area. In FIG. 2, the ECC unit 1 contains no error, and includes system data. Thus, the system data in the ECC unit 1 is first stored in the first memory area. After the system data is stored in the first memory area (step S409), the process proceeds to step S407. In step S407, it is determined whether or not the currently reproduced ECC unit contains an uncorrectable error. In FIG. 2, the ECC unit 1 contains no error. Thus, the process ends. Data processing in the ECC unit 2 will now be described. Since the ECC unit 2 contains an uncorrectable error, system data cannot be detected in step S401. Then, the process proceeds to step S407. In step S407, it is determined whether or not the ECC unit 2 contains an uncorrectable error. Since the ECC unit 2 contains an error, the process proceeds to step S408. In step S408, an internal error flag indicating that the reproduced ECC unit contains an error is set. Then, the process ends. A process for reproducing the ECC unit 3 containing no error that follows the ECC unit 2 containing an error will now be described. Since the ECC unit 3 contains no uncorrectable error, system data is detected in step S401. Then, an error flag is checked to determine whether or not any preceding ECC unit contains an error (step S402). In this example, the ECC unit 2 contains an uncorrectable error, and the error flag is set. Thus, the process proceeds to step S403. In step S403, it is determined whether or not the system data detected in step S401 is system data multiplexed at the head of a GOP in the MPEG stream. If it is system data multiplexed at the head of a GOP, the detected system data is stored in the second memory area of the buffer managing unit 106 (S404). In this example, it is assumed that the system data in the ECC unit 3 resides at the head of a GOP, and the system data in the ECC unit 3 is stored in the second memory area. At this time, the system data in the ECC unit 1 is stored in the first memory area of the buffer managing unit 106, and the system data in the ECC unit 3 is stored in the second memory area. The system data stored in the first and second memory areas are used to perform a substitution procedure described below on the data in the ECC unit 2 containing an uncorrectable error and the preceding and succeeding data (step S405). In step S406, the error flag is reset, and the process proceeds to step S407. It is determined in step S407 that the ECC unit 3 contains no uncorrectable error, and then the process ends. FIG. 5 is a flowchart showing the substitution procedure in step S405 shown in FIG. 4. In the present embodiment, as described above, the system data detected immediately before an ECC unit containing an uncorrectable error and the system data at the head of the GOP detected immediately after the ECC unit are backed up. The difference between the values of the DTSs in these system data is determined (step S501), and a series of frames between these system data, including the ECC unit containing the error, is detected (step S502). The number of frames between the system data detected immediately before and after the ECC unit containing the error is given as follows: number of frames=(difference between DTSs in the system data before and after the error/(clock speed))×frames per second For example, in the case where the system has a 27 MHz system clock and data having 30 frames per second (fps), the above equation is as follows: number of frames=(difference between DTSs in the system data before and after the error/(27×106))×30 In the present embodiment, the buffer managing unit 106 uses data indicating that the difference between the current data and data immediately previous to the current data is 0 in an MPEG system (hereinafter referred to as “Copy-Picture data”). The MPEG stream data stored in the stream buffer 103 that resides between the system data in the ECC unit 1 and the system data in the ECC unit 3 is substituted with the Copy-Picture data corresponding to the number of frames given in the above-noted equation. When the Copy-Picture data is input to the decoder 104, the decoder 104 outputs the decoded image data of the reference frame. The reproduced image of the Copy-Picture data is therefore the same as the image of the reference frame. The Copy-Picture data is MPEG data indicating zero difference, and has a small amount of data. Thus, insertion of the Copy-Picture data can cause an underflow of the VBV buffer. In order to avoid such an underflow problem, the amount of data for the error period is determined, and stuffing data (or dummy data) is generated by subtracting the amount of Copy-Picture data from the determined amount of data. The generated stuffing data is put in place of the MPEG data for the error period stored in the stream buffer 103 (steps S503 and S504). The amount of stuffing data is determined as follows: amount of stuffing data=(difference between the DTSs/(clock speed) +(VBV_Delay value of the system data before the error−VBV_Delay value of the system data after the error))×recording rate−the amount of Copy-Picture data The period between the system data before and after an ECC unit containing an uncorrectable error is regarded as an error period. The data corresponding to the error period is substituted with the Copy-Picture data, and the stuffing data is further inserted to prevent the VBV buffer specified by MPEG from causing an overflow before and after the Copy-Picture data. Thus, if an uncorrectable error occurs, the reproduced image for the error period can be displayed by freezing the preceding image on the screen. The error data in the MPEG stream is substituted with the Copy-Picture data, thus allowing even an external decoder to show a screen on which the preceding image is frozen during the error period when the MPEG stream is output from the DIF 108, which gives a better viewing screen to the user. In FIG. 2, the ECC unit 3 that follows the error period includes P picture data and B picture data, and the ECC unit 2 containing an error may include a reference picture data of the P picture data and the B picture data. In the present embodiment, all data from the system data reproduced after an ECC unit containing an uncorrectable error to the system data multiplexed at the head of a GOP is substituted with the Copy-Picture data. This prevents the ECC unit data reproduced after an ECC unit containing an error from being incorrectly decoded. In MPEG data, as described above, an I picture resides at the head of a GOP. Thus, the data from the head of the GOP can be correctly decoded. In the present embodiment, system data is multiplexed before the I picture and P pictures in one GOP. However, the present invention is not limited thereto, and system data may be multiplexed before the I picture that resides at the head of a GOP. In this case, the data of the GOP including image data of an ECC unit containing an uncorrectable error is substituted with the Copy-Picture data, and the number of pictures of the Copy-Picture data is equal to the number of pictures of one GOP. In the illustrated embodiment, the present invention is applied to an apparatus that reproduces an MPEG stream recorded on a tape. The present invention may also be applicable to reproduction of data encoded using a coding technique in which the amount of data changes depending upon the frame, such as MPEG. According to the present embodiment, therefore, a picture including error data is substituted with encoded data so as to output the same image as a picture immediately before the picture, thus giving a better reproduced picture when decoded. While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. This application claims priority from Japanese Patent Application No. 2004-036813 filed Feb. 13, 2004, which is hereby incorporated by reference herein. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a reproducing apparatus, and more specifically to processing of error data in encoded image data. 2. Description of the Related Art An apparatus for encoding video data using an encoding technique, such as MPEG (moving picture expert group), and recording and reproducing the encoded data is disclosed in, for example, Japanese Patent Laid-Open No. 2003-46944 (corresponding U.S. Published Application No. 2003/26590). In this recording and reproducing apparatus, if reproduced encoded data is missing, the missing data is substituted with encoded data of a specific color, such as black or gray. However, this apparatus outputs a black or gray picture for missing data, and gives an undesirable image to the user. Moreover, if black or gray data is merely inserted in an encoded stream, the resulting stream is not verified with the buffer model (VBV (video buffering verifier) buffer) that is specified by MPEG, and a decoder may cause decoding failure due to underflow or overflow of data stored in a buffer memory. | <SOH> SUMMARY OF THE INVENTION <EOH>In order to overcome the foregoing problems, the present invention provides a system for preventing decoding failure if missing data, such as an error, occurs in an encoded stream to give a desirable reproduced screen. In an aspect of the present invention, a reproducing apparatus includes a reproducing unit that reproduces a video data sequence including video data of a plurality of pictures from a recording medium, the video data sequence being encoded by a coding method in which the amount of data per picture changes from one picture to another, an error correcting unit that corrects the video data sequence reproduced by the reproducing unit for an error, and a control unit that performs substitution on the video data sequence so that data of a picture including an error that is uncorrectable by the error correcting unit is substituted with predetermined encoded data so as to output the same image as a picture immediately previous to the picture including the uncorrectable error when the video data sequence is decoded. Further features and advantages of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. | 20050118 | 20100706 | 20050818 | 63859.0 | 0 | ZHAO, DAQUAN | REPRODUCING APPARATUS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,037,745 | ACCEPTED | Method for assembly of a motorcycle frame | A method and apparatus for assembling motorcycle frames includes a conveyor defining a path of travel and at least one pallet movable along the conveyor through at least one workstation. The pallet supports at least one rotatable frame for receiving individual components and/or sub-assemblies in fixed relationship with respect to one another in a geometry fixture. The angular position of the rotatable frame and supported geometry fixture can be reoriented about an axis of rotation by engagement with a drive motor. The rotatable frame is normally locked in an angular orientation with respect to the pallet until released by engagement with a lock release actuator or key. The pallet is supported on a movable section of the conveyor. The movable section of the conveyor is operable in response to actuation of a drive motor. When the movable section of the conveyor and supported pallet are moved, the movable section of the conveyor is guided between raised and lowered positions with respect to the workstation, and the support pallet is accurately and repeatably positioned with respect to the workstation for automated processing operations at the workstation. | 1. A method for assembling a plurality of different frames on a single assembly line comprising the steps of: locating a pallet in at least one workstation; rotatably supporting at least one fixture on the pallet, the at least one fixture having anon-vertical axis of rotation and for receiving components of a frame to be assembled in fixed relationship to one another; and locking each of the at least one rotatable fixture supported on the pallet in a desired angular orientation with respect to the pallet. 2. The method of claim 1 wherein the locking step further comprises the steps of: connecting at least one latch to the pallet for movement between a locked position and an unlocked position with respect to each of the at least one rotatable fixture; and biasing each of the at least one latch toward the locked position. 3. The method of claim 2 wherein the biasing step further comprises the steps of: moving a reciprocal lock member between an engaged position and a disengaged position, such that the lock member is engaged with the latch for holding the latch in the locked position when in the engaged position, and such that the lock member moves the latch to the unlocked position when in the disengaged position; and biasing the lock member toward the engaged position with a spring. 4. The method of claim 3 further comprising the step of moving the lock member from the engaged position to the disengaged position. 5. The method of claim 4 wherein the moving step further comprises the step of: engaging an actuator with the lock member for moving the lock member from the engaged position against the urging of the biasing spring toward the disengaged position. 6. The method of claim 1 further comprising the step of: adjusting an angular orientation of the corresponding fixture about an axis of rotation with respect to the pallet with at least one drive engageable with each of the at least one rotatable fixture. 7. The method of claim 1 further comprising the step of: moving the pallet along a conveyor defining a path of travel through the at least one workstation. 8. The method of claim 7 further comprising the step of: moving a movable section of the conveyor located at the workstation between a first position and a second position. 9. The method of claim 8 further comprising the step of: locating the pallet with respect to the movable section of the conveyor. 10. The method of claim 8 wherein the moving step further comprises: rotating of a crank arm having a cam follower connected adjacent to an outer radial end of the crank arm with respect to an axis of rotation, the cam follower engageable within an elongate slot associated with the movable section of the conveyor. 11. The method of claim 1 further comprising the step of: controlling movement of the pallet and each of the at least one rotatable fixture in response to a signal corresponding to an identification of a frame to be assembled at the workstation. 12. The method of claim 1 further comprising the step of: locating the pallet with respect to the workstation. 13. A method for assembling a plurality of different frames on a single assembly line comprising the steps of: locating a movable pallet in at least one workstation located along a path of travel; rotatably supporting at least one fixture on the pallet, the at least one fixture having anon-vertical axis of rotation and for receiving components of a frame to be assembled in fixed relationship to one another; locking each of the at least one rotatable fixture supported on the pallet in a desired angular orientation with respect to the pallet; and welding the components of the frame to one another. 14. The method of claim 13 further comprising the step of: rotating the at least one fixture about a generally horizontal axis of rotation. 15. The method of claim 13 further comprising the steps of: rotating the at least one fixture including a first fixture and a second fixture about generally parallel horizontal axes of rotation; simultaneously engaging and locking the first and second fixtures against further rotation when in a locked position with the locking means including a single lock; and adjusting an angular orientation of the fixtures about the axes of rotation with respect to the pallet with at least one drive engageable with the first and second fixtures. 16. The method of claim 13 further comprising the steps of: assembling the plurality of different frames defining different models of motorcycle frame to be assembled along the single assembly line; and controlling angular movement of the at least one rotatable fixture about the non-vertical axis of rotation with control means, responsive to a signal corresponding to an identification of a motorcycle frame to be assembled at the workstation. 17. The method of claim 13 further comprising the step of: controlling angular movement of the at least one rotatable fixture about the non-vertical axis of rotation with control means responsive to a signal corresponding to an identification of the at least one rotatable frame supported on the pallet to be delivered to the workstation. 18. The method of claim 13 further comprising the step of: the at least one fixture including first and second fixtures, each fixture located generally parallel to one another having a generally horizontal axis of rotation. 19. The method of claim 18 further comprising the steps of: locking each of the at least one rotatable fixture supported on the pallet in a desired angular orientation with respect to the pallet with a single lock for simultaneously engaging and locking the first and second fixtures against further rotation when in a locked position; and adjusting an angular orientation of the fixtures about the axes of rotation with respect to the pallet with at least one drive engageable with the first and second fixtures. 20. The method of claim 13 further comprising the steps of: assembling the different frames defining different models of motorcycle frames to be assembled in any sequential order along the single assembly line; and controlling angular movement of the at least one rotatable fixture about the non-vertical axis of rotation with control means, responsive to a signal corresponding to an identification of a motorcycle frame to be assembled at the workstation. | RELATED APPLICATIONS The present application is a Divisional application of patent application Ser. No. 10/195,943 filed on Jul. 15, 2002, which claims the benefit of provisional application Ser. No. 60/379,539 filed on May 9, 2002. FIELD OF THE INVENTION The present invention relates to a method and apparatus for the flexible assembly of a plurality of motorcycle frames on a single assembly line. BACKGROUND OF THE INVENTION The current assembly of motorcycle frames typically includes a primary work cell where several individual frame components are brought together and welded to one another. The current approach requires highly specialized work cells, each work cell dedicated to a particular frame configuration. Flexibility of the manufacturing process is limited. SUMMARY OF THE INVENTION A method and apparatus according to the present invention conveys workpieces along a path of travel. The path of travel can be an assembly line for the assembly of motorcycle frames. A plurality of pallets are movable along the path of travel defined by the convey system of the assembly line. Each pallet supports at least one workpiece-supporting frame or ring. A plurality of differently configured workpieces can be supported for movement along the path of travel. The workpieces can form a motorcycle frame constructed from individual components positioned with respect to one another in the frame or ring. Each frame or ring has at least one geometry-locating fixture for supporting and locating individual components in predetermined positions with respect to one another. Each geometry-locating fixture is removably associated with the corresponding frame or ring to accommodate the plurality of differently configured workpieces. Each geometry-locating fixture can include one or more elements selected from clamps, pins, guides or any combination thereof. Each frame or ring can be individually rotated through a predetermined angular arc at one or more workstations positioned along the path of travel to reorient the angular position of the workpiece being constructed to a desired angular position with respect to the rotational axis during processing operations. By way of example and not limitation, a frame or ring can be rotated to reorient a workpiece in an inverted orientation, so that a welding robot can perform a welding operation from above for easier access. Each frame or ring can be conveyed along the path of travel by pallets carried along a conveyor located at, above, or below, the manufacturing floor depending on the particular application and plant layout. Each pallet can rotatably support one or more frames or rings. Each pallet can include a lock to prevent movement of the associated frame or ring during movement of the pallet along the path of travel. The individual pallets can be moved along the conveyor defining the path of travel. The conveyor can extend along the path of travel between and through one or more workstations. The reorientation of the angular position of the frame or ring and the associated workpiece being constructed can be performed by bringing the pallet and an associated lock into operable engagement with a lock release and a motor or drive for rotating the frame or ring about an axis of rotation. By way of example and not limitation, the conveyor can be divided into individual sections, where some conveyor sections can be vertically moveable with respect to the path of travel for raising and lowering a pallet and associated workpiece carried thereon with respect to the workstation. For purposes of illustration, when a particular conveyor section is moved vertically, either raised or lowered relative to the workstation, the associated frames or rings can engage one or more motors for rotating the associated frames or rings with respect to the pallet. Rotation of each frame or ring results in reorientation of the associated workpiece being constructed into a desired position of angular orientation with respect to the axis of rotation. When properly oriented for the next processing operation, the pallet can be returned by lowering or raising the particular conveyor section, to the original position for delivery to the next workstation. Alternatively, the motor and lock release can be moved relative to the conveyor and/or pallet between an engaged position for reorienting the workpiece and a disengaged position allowing delivery and removal of the pallets along the conveyor. Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: FIG. 1 is an exploded perspective view of a conveyor including a pallet movable along the conveyor for supporting associated frames or rings to receive a workpiece to be constructed, and reorienting means for rotating the associated frames or rings with respect to the supporting pallet according to the present invention; FIG. 2 is a schematic view of an assembly line according to the present invention; FIG. 3 is a perspective view of two frames or rings according to the present invention; FIG. 4 is side view of a frame or ring having removable fixtures connected thereto for receiving a workpiece to be constructed according to the present invention; FIG. 5 is a perspective view of a pallet for carrying one or more frames or rings according to the present invention; FIG. 6 is a detailed side view of a lock for locking one or more frames or rings with respect to the pallet according to the present invention; FIG. 7 is a detailed sectional view of the lock in a locked position; FIG. 8 is a sectional detailed sectional view of the lock in an unlocked position; FIG. 9 is a perspective view of the conveyor according to the present invention; FIG. 10 is a perspective view of reorienting means according to the present invention; FIG. 11 is a perspective view of the pallet, conveyor and reorienting means engaged with respect to one another according to the present invention; FIG. 12 is a side sectional view of the pallet, the conveyor and the reorienting means engaged according to the present invention; FIG. 13 is a perspective view of the conveyor engaged with positioning means for positioning the pallet with respect to the workstation and locating means for locating the conveyor with respect to the workstation; FIG. 14 is a partial exploded view of positioning means and locating means according to the present invention; FIG. 15 is partial exploded view of positioning means and locating means according to the present invention; FIG. 16 is a side view of an assembly line according to the present invention; FIG. 17 is a simplified flow diagram illustrating steps performed when a pallet is moved with respect to a workstation; FIG. 18 is a perspective view of a workstation according to the present invention; FIG. 19 is a schematic plan view of two workstations positioned adjacent to one another along the path of travel; and FIG. 20 is a simplified flow diagram illustrating steps performed when the workpieces are processed at a workstation according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, the present invention includes conveyance means 10 for transporting one or more workpieces along a path of travel 12 between and through one or more workstations 14a-14g positioned along the path of travel 12. Workpiece conveyance means 10 can include a pallet 20 movable along a conveyor 22 defining the path of travel 12. Each pallet 20 rotatably supports at least one frame or ring 18a, 18b. The conveyor 22 can include a plurality of sections operably associated with the pallet 20. A conveyor section can be located at each of the workstations 14a-14g. Positioning means 16 can be located relative to workstations for accurately positioning each pallet with respect to the workstation prior to performing any work on the workpieces. Positioning means 16 can operably engage the pallet 20 and/or the conveyor section 22 to accurately locate the pallet with respect to the workstation. At least one locating pin is operably associated with the positioning means 16 and can engage with the pallet 20, as either the pallet or locating pin is moved between a first position disengaged with respect to one another and a second position engaged with respect to one another. The conveyor 22 moves workpieces between workstations 14a-14g, where one or more processing operations are performed on the workpieces. By way of example and not limitation, the present invention can define a motorcycle frame assembly line where workpieces, such as a plurality of individual components and/or sub-assemblies of a motorcycle frame are assembled with respect to one another at the workstations 14a-14g along the path of travel 12. Referring now to FIG. 2, sub-assembly stations 24a-24d can be positioned in a feeding relationship with respect to the path of the travel 12. Each sub-assembly station 24a-24d can be a single cell workstation, or a multiple cell workstation for assembling one or more sub-assemblies of the motorcycle frame. By way of example and not limitation, sub-assembly station 24a can assemble a horizontal tube subassembly: sub-assembly station 24b can assemble a vertical tube subassembly; sub-assembly station 24c can assemble a backbone/C-pan subassembly; and sub-assembly station 24d can assemble a fender rear forging subassembly. The assembled sub-assemblies can be placed on associated feeder lines, such as feeder lines 26a-26d, and moved to a loading station 14b positioned on the path of travel 12. The sub-assemblies are received at the loading station 14b and are loaded into a geometry fixture carried by the rotatable frame 18a, 18b supported on the pallet 20 for movement along the conveyor 22. Additional components, such as, a steering head assembly casting, a right-hand and a left-hand front engine mount casting, a rear motor mount casting, and a tie link piece, or part, can be installed into the geometry fixture at the loading station 14b. The geometry fixture carried by the rotatable frames 18a, 18b can receive the workpieces 11a, 11b, such as sub-assemblies and other components, in fixed predetermined geometric positions with respect to one another for final assembly into a single unitary motorcycle frame assembly. Referring now to FIGS. 3 and 4, workpieces 11a, 11b can be installed within geometry fixtures carried by rotatable frames 18a, 18b. Each frame or ring 18a, 18b can support one or more elements 28a-28f defining each geometry-locating fixtures. The elements 28a-28f of each geometry fixture can be selected from one or more clamps, brackets, pins, grippers, guides or any combination thereof. Some of the elements 28a-28f of a geometry fixture can be powered by connection to an appropriate source of pneumatic, hydraulic or electric power. Powered elements of a geometry fixture associated with a corresponding rotatable frame or ring 18a, 18b can be engaged by a Staughbly system if desired. After the sub-assemblies and components corresponding to the workpiece 11a, 11b to be processed are loaded with respect to the elements 28a-28f of the geometry fixtures carried by the rotatable frame or ring 18a, 18b, the powered elements can be driven from a disengaged position to an engaged position for holding the relative geometry of the overall workpiece to be processed until the processing operations are complete. Lines 30 for the pneumatic, hydraulic and/or electric power can be mounted along a periphery of each rotatable frame or ring. The elements 28a-28f defining each individual geometry fixture can be removably associated with the rotatable frame or ring 18a, 18b to accommodate a plurality of differently configured workpieces for assembling a plurality of differently configured motorcycle frames. The elements 28a-28f forming a geometry fixture can be exchanged with other elements or can be repositioned along the periphery of the frame or ring 18a, 18b with respect to one another for receiving and locating different sub-assemblies and/or components in a different predefined geometry with respect to one another during assembly. Each frame or ring 18a, 18b can include similar fixtures with respect to one another, or alternatively can include different fixtures for processing different workpieces at the same time. In certain circumstances, it may be desirable to associate a different geometry fixture with the frame or ring 18a than the geometry fixture associated with the frame or ring 18b to simultaneously assemble differently configured motorcycle frames on the same line. Each frame or ring 18a, 18b includes a plurality of gear teeth 32 disposed along at least a portion of a periphery 34 of an arc segment connected to the frame or ring 18a, 18b. The teeth 32 allow controlled movement between angular positions with respect to an axis of rotation of each frame or ring 18a, 18b supported with respect to the associated pallet 20. The gear teeth 32 can be operably engaged by a drive gear to move the frame or ring 18a, 18b in rotation about the rotational axis with respect to corresponding pallet 20 and can be engaged by a lock to prevent relative rotational movement of the frame or ring 18a, 18b about the rotational axis with respect to the corresponding pallet 20 during movement of the pallet 20 along the conveyor 22. Referring now to FIGS. 1 and 5, each rotatable frame or ring 18a, 18b, can be rotatably supported by an associated pallet 20 for movement along the path 12. Each pallet 20 can include a plurality of horizontal frame members, 36a-36f and two or more vertical frame members 38a-38c. Each pallet 20 can also include a plurality of rollers for supporting the rotatable frames or rings 18a, 18b. Each pallet 20 can include rollers 40a-40b having support surfaces 42a-42b for engaging a surface 44a, as best shown in FIG. 3, of the corresponding rotatable frame or ring 18a, and rollers 40c-40d having support surfaces 42c-42d for engaging a surface 44b, as best shown in FIG. 3, of the associated rotatable frame or ring 18b. Aligning rollers 46a-46p can be provided on each pallet 20 for engaging the surfaces 45a-45b of the associated rotatable frames or rings 18a, 18b. Referring now to FIGS. 5-8, each pallet 20 can include a lock 48 to prevent the associated rotatable frame or ring 18a, 18b from rotating with respect to the pallet 20 during movement of pallet 20 along the path of travel 12. A lock 48 can be supported with respect to the vertical frame 38b of each pallet 20 between the rotatable frames or rings 18a, 18b. The lock 48 can be normally biased to the locked position. A lock-release actuator or key associated with a workstation can operably engage the lock 48, when the lock 48 is positioned at a workstation and movement of the rotatable frame 18a, 18b with respect to the pallet 20 is desired. The lock-release actuator or key can manipulate a pin 50 forming part of the lock 48. The pin 50 is moveable between a first position, normally locking the rotatable frames 18a, 18b with respect to the pallet 20, as best shown in FIG. 7, and a second position, releasing the rotatable frames 18a, 18b with respect to the pallet 20, as best shown in FIG. 8. FIG. 6 illustrates pin 50 in phantom in both positions. The locked position of the pin 50 corresponds to the normally biased position of the lock. The unlocked position of the pin 50 corresponds to the position when manipulated by the lock-release actuator or key. In one configuration, the locked position corresponds to the conveyor in the raised position, and the unlocked position corresponds to the conveyor in the lowered position. Alternatively, it should be recognized that the lock-release actuator or key could be moved relative to the pallet 20, while the conveyor 22 is stationary. The lock 48 can include at least one arm rotatable about an axis in response to movement of the pin 50 between the locked position and the unlocked position. Preferably, the lock 48 includes at least one arm for each rotatable frame or ring 18a, 18b supported by the pallet 20. As shown in FIGS. 6 and 7, the lock 48 can include first and second arms 54a, 54b rotatable about corresponding axes 56a, 56b, respectively. Each arm 54a, 54b includes a first projection 58 for engaging the gear teeth 32 when the pin 50 is in the locked position as shown in FIG. 7. The first projection 58 is retracted with respect to the gear teeth 32 when the pin 50 is in the unlocked position as shown in FIG. 8. Each arm 54a, 54b includes a release lever 60. The release lever 60 is engaged by surface 62 of the pin 50. When pin 50 is moved to the unlocked position, the surface 62 engages the lever 60 to rotate the arms 54a, 54b about an axis of rotation causing retraction of the projection 58 with respect to the gear teeth 32 associated with the rotatable frame 18a, 18b. The arms 54a, 54b can include a follower surface 61 engageable with a cam surface 63 of the pin 50, as best seen in FIG. 8. When pin 50 is moved to the locked position, the cam surface 63 of the pin 50 engages the follower surface 61 of the arms 54a, 54b to rotate the arms 54a, 54b about the axis of rotation to cause locking engagement of projection 58 with respect to gear teeth 32. Biasing means 52 urges the lock 48 toward the locked position, schematically shown in FIG. 6, causing pin 50 to normally be in the locked position with respect to the rotatable frame or ring 18a, 18b carried by the associated pallet 20 until acted on by the release actuator or key. Biasing means 52 can include a spring interposed between a pin housing 53 and a shoulder 55 formed on the pin 50. The rings 18a, 18b can be locked in a particular orientation with respect to the pallet 20 until reorientation is required. If various consecutive workstations require the workpiece to be in a common fixed angular orientation, processing operations can be optimized by locking the rotatable frames in a desired orientation while passing through the particular workstations. Each pallet 20 can be moved along the path of travel 12 by the conveyor 22 having a plurality of sections. Referring now to FIG. 9, the conveyor 22 can include longitudinal members 64a and 64b and transverse members 66a-66h immovably associated with respect to one another. The longitudinal members 64a and 64b and the transverse members 66a-66h can define a plurality of apertures 68a-68g. A plurality of shafts 70a-70f, are provided on the conveyor 22 for moving pallets 20 along the path 12. Each shaft 70a-70f can be mounted along surfaces 72a, 72b of the longitudinal members 64a, 64b with bearings 74a, 74b. Each shaft 70a-70f supports a pair of drive wheels 76a, 76b, fixedly connected to the shaft. Each drive wheel 76a, 76b includes a corresponding support surface 80a, 80b, respectively, for engaging surfaces 82a, 82b of the pallet 20, as best shown in FIG. 5. The shafts 70a-70f can be rotated by a drive motor 84 operably connected to a transmission 86 and one or more drive members, such as belts 90. Each shaft and associated drive wheels 76a, 76b can be driven by a pulley 88 fixedly connected to the shaft for operably engaging with a corresponding drive member, such as belts 90. The pulley 88 can be connected to one end of each shaft 70a-70f as best seen in FIG. 9, or alternatively, pulleys 71 can be fixedly connected on shafts 70a-70f interposed between the fixed wheels 76a, 76b, as best shown in FIGS. 13 and 16a-16b. In either case, the shafts 70a-70f and connected drive wheels 76a, 76b can be rotated in unison with respect to one another for transmitting linear motion to the pallet 20 carried on the drive wheels 76a, 76b. A drive motor 84a can be operably associated with a transmission 86a to directly drive one the shafts 70a-70f and drive at least one other shaft through associated drive members, such as belts 90a and pulleys 71. The conveyor 22 can also include brackets 92a-92d. Each bracket 92a-92d can be mounted to a surface 94a or 94b of the longitudinal members 64a, 64b. Each bracket 92a-92d defines an elongate slot or aperture for moving the movable section of the conveyor 22 between the first position and the second position with respect to the workstation. At least one section of the conveyor 22 is supported for movement with respect to workstation and/or adjacent stationary sections of the conveyor 22. Referring now to FIGS. 1, 10 and 11, a base 17 can support a vertical movement drive 104a, 104b for the movable section of the conveyor 22, ring drivers 128a, 128b, and a lock release actuator 142. The base 17 can be defined by longitudinal members 96a, 96b, transverse members 98, plates 100a-100c, and risers 102. Vertical movement drive 104a, 104b can vertically move the section of the conveyor 22 between a first position and a second position relative to the base 17. The vertical movement drive, 104a, 104b can include a shaft 106 supporting a pair of rotatable members, such as a crank arm or disk, at each end. Each shaft 106 can include a roller or cam connected at a position spaced radially from the axis of rotation of the crank arm or disk. Each shaft 106 can be supported by bearings 108 mounted on one of the plates 100a or 100c. A pulley 110 can be fixedly connected to the shaft 106 for driving the fixedly connected crank a=s or disks at each end of the shaft in simultaneous rotary motion. The pulley 110 can engage a drive member 112, such as a belt, for rotating the shafts 106 simultaneously with respect to one another to raise and lower the movable section of conveyor 22 and supported pallet 20 in a controlled manner for engagement with the base 17 and associated ring drivers 128a, 128b. The drive member 112 can be driven by a motor 114 operably connected through a transmission 116 for rotating a shaft 118 fixedly connected to pulleys 120a, 120b for driving the drive members 112, 122 and for transmitting rotary motion to the shafts 106. The rotary motion of each shafts 106 is converted into linear vertical motion of the movable section of the conveyor 22 through the rollers or cams engaging within the elongate slots or apertures formed in the brackets 92a-92d as best seen in FIG. 9. The shafts 106 can be supported through bearings 124a-124c. Each cam or roller 126a, 126b is located at an end of the shaft 106. The cams or rollers 126a, 126b include crank arms 240a, 240b, respectively. The cams or rollers 126a, 126b are received within the elongate slots or apertures of the brackets 92a-92d of the movable section of the conveyor 22. The shafts 106, 106a and associated cams or rollers can be rotated between at least a first position and a second position. The first position corresponds to a raised position of the movable section of the conveyor 22 relative to the base 17. The second position corresponds to a lowered position of the movable section of the conveyor 22 relative to the base 17. In FIG. 10, the cams or rollers 126a, 126b are shown in the second, or lowered position. Preferably, the movable section of the conveyor 22 moves vertically with respect to the base 17, while movement transverse and/or longitudinal with respect to the path of travel 12 is prevented with appropriate guides and/or supports as required. Reorienting means 15 can include ring drivers 128a and 128b for moving the rotatable frames or rings 18a, 18b when the movable section of the conveyor 22 is in a lowered position relative to the base 17. Each ring driver 128a, 128b can be mounted to corresponding plate 100a, 100c. Each ring driver 128a, 128b includes a body 130, a motor 132, frame supports 134a, 134b, and a drive gear 136. The body 130 positions the drive gear 136 having gear teeth 140 in intermeshing engagement with the gear teeth 32 of the corresponding rotatable frame or ring 18a, 18b when the associated pallet 20 and the movable section of the conveyor 22 are lowered relative to the base 17 at the workstation. The drive motor 132 rotates the drive gear 136 causing corresponding rotation of the rotatable frame or ring 18a, 18b when the movable section of the conveyor 22 is in the lowered position. The frame supports 134a, 134b include wear pads 138a, 138b, respectively, engageable with surface 44a, 44b of the corresponding rotatable frame or ring 18a, 18b when the associated pallet 20 and the movable section of the conveyor 22 are lowered relative to the base 17 of the workstation. Referring now to FIGS. 10 and 12, the reorienting means 15 can include a lock release actuator 142 engageable with a lower end 144 of the pin 50 for moving the pin 50 against the urging of the biasing means 52 toward the second position as the pallet 20 and movable section of the conveyor 22 are lowered relative to the base 17. As the movable section of the conveyor 22 is lowered relative to the base 17, the lower end 144 of the pin 50 engages the lock release actuator 142 to move the pin 50 to the unlocked position when the movable section of the conveyor reaches the lowered position. The lock release actuator 142 can include a replaceable wear pad 146 for engaging the lower end 144 of the pin 50. Referring now to FIGS. 11 and 12, a plate 148 can be disposed adjacent a top portion of the movable section of the conveyor 22. The plate 148 defines a plurality of apertures allowing flanges 150 and surfaces 80a, 80b of wheels 76a, 76b to engage pallet 20 through the apertures. Ring drivers 128a, 128b are allowed to engage rotatable frames or rings 18a, 18b, and lock release actuator 142 is allowed to engage lock 48 through the apertures. The plate 148 prevents entry of debris into contact with belts 90, 112, 122 and pulleys 88, 110, 120a associated with the movable section of the conveyor 22 and base 17. The plate 148 can be supported by brackets 152 mounted to the longitudinal members 64a and 64b of the movable section of the conveyor 22. Referring now to FIGS. 13-15, the present invention includes positioning means 16 for locating the pallet 20 with respect to the base 17 when the pallet 20 and movable section of the conveyor 22 are lowered relative to the base 17. Positioning means 16 can include a first locating pin 156 mounted with respect to a riser 158. The pin 156 can be tapered to accommodate slight misalignments between the pallet 20 and the pin 156. The riser 158 can be mounted to a plate 160 associated with the base 17, as shown in FIG. 10. The pin 156 can be located at a downstream end of the base 17 with respect to flow of workpieces 11a, 11b along the path of travel 12. The pin 156 operably engages within an aperture 162 located on an underside of the pallet 20, best shown in FIG. 5. The pin 156 accurately locates the pallet 20 and associated workpieces carried by the geometry fixtures of the rotatable frames and rings 18a, 18b with respect to the automated processing equipment associated with the workstation, such as programmable robots for automated welding operations. The pin 156 prevents transverse or side-to-side movement of the pallet 20 as well as longitudinal or upstream and downstream movement of the pallet 20 when engaged. Accurately locating consecutive workpieces with respect to the workstation as the workpieces move along the path of travel during processing is critical in order to provide a repeatable, high quality processed workpiece at the end of the assembly line. Minor variations in positioning of the workpieces at the workstations can introduce undesirable variations in the quality of the finished workpieces. The pallet positioning means 16 can include roller guides 164. The roller guides 164 include rollers 166a, 166b rotatably mounted to a plate 168. The plate 168 includes a slot 170 for receiving a locating member 172 of the pallet 20, as best seen in FIG. 5. The locating member 172 moves between the rollers 166a, 166b as the pallet 20 is lowered relative to the base 17. The rollers 166a, 166b can be connected to the plate 168 with appropriate fasteners, such as nuts 174. The plate 178 can be mounted with respect to a plate 176 on the base 17. The pallet positioning means 16 can also include guides 178a-178f Each guide 178a-178f can include a guide plate 180a, 180b (FIG. 13-15) and supports 182a-182f for positioning the guide plate in a desired position relative to the base 17. The horizontal frame member 36b of the pallet 20 engages the guide plates 180a, 180b as the pallet 20 is being lowered relative to the base 17 to locate the pallet in a direction transverse to the flow of workpieces along the path 12. Guides 178a-178f can be mounted on the longitudinal members 96a and 96b of the base 17. One or more guides 178b, 178f can include a sensor for sensing the proximity of the pallet 20. A projection 188, 188a formed on the pallet 20, as best seen in FIG. 5, can move between the prongs 190a, 190b of a sensor 184, 184a (FIGS. 14 and 15 respectively) as the pallet 20 is lowered with respect to the base 17. The sensor 184, 184a can emit a signal corresponding to proximity of the projection 188, 188a to the sensor, where the emitted signal is received by a controller 220 (FIGS. 13 and 18). Sensor 184, 184a can be mounted to any appropriate guide with a bracket 186 and a spacer element 192. The plate 180b can be mounted to the beam 182b with a spacer element 194. The pallet positioning means 16 can be located at each workstation where automated processing is to be performed on the workpiece requiring repeatable, accurate location of the workpiece relative to the workstation. At these workstations, the pallet 20 is lowered relative to the base 17 to operably engaging the pallet positioning means 16 located at the workstation. A conveyor locating or guiding means 196 (FIGS. 13 and 14) prevents transverse and longitudinal movement of the movable section of the conveyor 22 relative to the base 17 as the movable section of the conveyor 22 is lowered with respect to the base 17. Conveyor locating means 196 can include a guide rod 198 rigidly mounted to a base 200. The base 200 is mounted to the plate 160 of the base 17. The conveyor locating means 196 includes a slide block 202 having an aperture formed therein for slidably receiving the guide rod 198 to move longitudinally along a length of the guide rod 198 as the movable section of the conveyor 22 and supported pallet 20 are moved between the raised position and lowered position. A plate 204 is mounted to the slide block 202. The plate 204 is connected to the transverse member 66g of the movable section of the conveyor 22 to prevent relative movement in any direction except vertical movement between the base 17 and the movable section of the conveyor 22. A bushing 206 can be located within the aperture of the slide block 202 to enhance the sliding movement of the slide block 202 relative to the guide rod 198. The conveyor locating means 196 can include a plate 246 and roller 248, best seen in FIG. 15. The plate 246 can be mounted with respect to the stationary member 176 mounted on the base 17. The roller 248 can engage a plate 246a (FIGS. 9 and 13) associated with the movable section of the conveyor 22. The plate 246a operably engages the roller 248 to locate the movable section of the conveyor 22 with respect to the base 17. Referring now to FIGS. 2 and 16, an assembly line according to the present invention includes workpiece conveyance means 10 defining the path of travel 12 and having workstations 14a-14g positioned along the path of travel 12. Workstation 14a can define a pallet receiving station where empty pallets 20 are positioned prior to loading workpieces 11a, 11b at the loading workstation 14b. Workstations 14c, 14d can define welding workstations for fixing the geometry of the individual sub-assemblies and components into a unitary one-piece frame while held in the geometry fixtures carried by the rotatable frames or rings 18a, 18b. Processing operations can be performed with respect to the workpieces 11a, 11b along the entire assembly line while the sub-assemblies and/or components are held in a geometry fixture ensuring accurate location of the individual components and/or sub-assemblies with respect to one another throughout the assembly process. Inspection of workpieces, unloading of workpieces, or any other operation can be performed with respect to the workpieces 11a, 11b at workstations 14e, 14f Workstation 14g can define a pallet return workstation. The path of travel 12 can include a first portion 208 corresponding to the pallet 20 moving through workstations 14b-14f. The path of travel 12 can include a second portion 210 corresponding to the pallet being returned to the loading workstation 14b. The second portion 210 can be located as an overhead return line, a below floor return line, or as a return loop line at floor level with respect to the first portion 208 depending on the particular application and plant layout. As illustrated in FIG. 16, by way of example and not limitation, when a pallet 20 reaches the workstation 14g at the end of the assembly line, the pallet 20 can be raised to an upper level and returned along a series of conveyor sections defining the second portion 210 positioned above the first portion 208. The workstation 14g can include a lift 216 for moving the movable section of the conveyor 22 between a raised position aligned with the conveyor sections of the conveyor 22 associated with the second portion 210 and a lowered position aligned with the conveyor sections of the conveyor 22 associated with the first portion 208. The workstation 14g can include drive means for raising the lift 216 along with the movable section of the conveyor 22 and a pallet 20 supported on the movable section of the conveyor 22 into alignment with the second portion 210 of the path of travel 12. After the pallet 20 has been moved to the raised position into alignment with the second portion 210 of the path of travel 12, the drive means can be actuated to operate lift 216 to move the movable section of the conveyor 22 to the lowered position into alignment with the first portion 208 of the path of travel 12. The elevated sections of the conveyor 22 positioned along the second portion 210 of the path of travel 12 can be supported by simplified elevated bases, since pallet positioning means 16 and conveyor locating means 196 are not required on the return line. The elevated sections of conveyor 22 can be connected with supports 212 to an elevated platform surface 214, as shown in FIG. 18. At the workstation 14a, a returning pallet 20 is received from the second portion 210 of the path of travel 12 and can be lowered into alignment with the first portion 208 of the path of travel 12 for delivery to the loading workstation 14b. The workstation 14a can include another lift 216 including a movable section of the conveyor 22 for supporting a pallet 20. During production changeover, or whenever maintenance is required, one pallet can be exchanged for another pallet at workstation 14a and/or workstation 14g. To perform an exchange of pallets at workstation 14a and/or 14g, a first pallet is received at the lift station 14a and/or 14g, when in a pallet removal position (typically the lowered position) the pallet can be transferred to an adjacent loading/unloading conveyor position (not shown) for removal, and after removal another pallet 20 can be loaded into the loading/unloading conveyor position (not shown) for transfer to the lift station 14a and/or 14g. To increase the speed and efficiency of pallet maintenance and/or production model changeover, one lift workstation 14a and/or 14g can be used to remove pallets 20 while the other lift workstation is used to load replacement pallets 20. It should be recognized that the rotatable frames or rings 18a, 18b can be exchanged with respect to the pallet 20 at the lift workstations 14a and/or 14g, or at an adjacent loading/unloading workstation (not shown). It should also be recognized that the fixtures 28a-28f can be exchanged with respect to the rotatable frames or rings 18a, 18b at the workstations 14a or 14g, or at an adjacent reconfiguration workstation (not shown). Any one or more of the pallets 20, rotatable frames or rings 18a, 18b, and elements 28a-28f defining geometry fixtures can be exchanged to move workpieces with a different geometry configuration along the path of travel 12 for assembly allowing greater flexibility in the production line configuration and mix of models being manufactured. Referring now to FIG. 17, movement of the pallet 20 into one of the workstations 14b-14f can begin by movement of the wheels 70a-70f of the movable section of the conveyor 22 of the previous workstation to rotate and move the pallet 20 to the movable section of the conveyor 22 of the receiving workstation. The receiving workstation can include one or more position sensors 222 for emitting a signal corresponding to the position of the pallet 20 relative to the movable section of the conveyor 22. The signals emitted by the position sensors 222, and position sensors 184, 184a (FIGS. 13 and 14) can be received by a controller 220 in communication with the motor 84. The controller 220 can control the motor 84 to decelerate the pallet 20 and stop the pallet at a predetermined position. After the pallet has been stopped, one or more sensors 224 emit signals corresponding to one or more of the following data: a unique identification for the workpiece being assembled; a unique identification of the individual pallet with respect to the plurality of pallets being transported by the conveyor 22; a unique identification of an individual rotatable frame or ring with respect to the plurality of rotatable frames or rings being transported on the conveyor; a unique identification of the particular configuration of the elements forming the geometry fixture associated with the particular rotatable frame or ring; the relative position of each element of the geometry fixture support by the rotatable frame or ring relative to other elements of the geometry fixture; and the angular orientation of the rotatable frame or ring and associated elements of the geometry fixtures relative to supporting pallet. Preferably, the sensors 224 are optical scanners, or laser switches or sensors. However, the sensors 224 can be any type of sensor, such as an optical sensor, or a programmable chip with data transfer capabilities associated with each pallet, each rotatable frame and each geometry fixture configuration. The unique identification of an individual pallet or an individual rotatable frame or ring among a plurality of pallets and frames or rings can be stored in memory of the controller 220 for analysis. The analysis can assist in determining the cause or source of rejected workpieces which can be cross-referenced to the individual pallet and individual frame or ring that moved the workpiece along the path 12 to identify any pallets, frames or rings that may be incorrectly configured or damaged. The sensors 224 can identify the configuration of elements 28a-28f forming each geometry fixture on each ring 18a, 18b, the position of the elements 28a-28f of each geometry fixture relative to one another, and the angular orientation of the rotatable frames or rings 18a, 18b relative to the pallet 20. The controller 220 can compare the signals received from the sensors and apply the signals in accordance with a control program stored in memory. The control program stored in memory can include data corresponding to a desired configuration of the elements forming each geometry fixture, a desired number of elements and the desired position of the elements relative to one another for forming a particular geometry fixture, and a desired angular orientation of the rotatable frame or rings 18a, 18b relative to the pallet 20. If the signals emitted by the sensors and received by the controller 220 do not correspond to the desired configuration of each element in a particular geometry fixture, and/or the desired number of elements in a particular geometry fixture and/or the desired position of elements forming the particular geometry fixture relative to one another and/or the desired angular orientation of the rotatable frames or rings 18a, 18b relative to the pallet 20, the controller can stop the motor 114 from lowering the movable section of the conveyor 22. The controller 220 can also emit a signal corresponding to an error message to a central controller or operator. The process steps followed by the controller 220 when a pallet 20 is moved to a receiving workstation are shown in the simplified flow diagram of FIG. 17. The process is applied to both rotatable frames or rings 18a, 18b. The process starts at step 226. Step 228 monitors the configuration of each element 28a-28f forming a geometry fixture removably associated with the rotatable frames or rings 18a, 18b. If any of the elements 28a-28f defining the geometry fixture is not a desired element, the process continues to step 230 and an error message is emitted to a central controller or operator. The process ends at step 232. If the configuration of each element 28a-28f defining the geometry fixture is the desired element, the process continues to step 234. Step 234 monitors the position of each element 28a-28f forming the geometry fixture relative to one another. If the elements 28a-28f defining the geometry fixture are not positioned as desired, the process continues to step 230 where an error message is emitted to a central controller or operator. If the elements 28a-28f defining the geometry fixture are positioned along the rotatable frame or ring 18a, 18b as desired, the process continues to step 236. Step 236 monitors the angular orientation of the rotatable frames or rings 18a, 18b relative to the pallet 20. If the frame or ring 18a, 18b is not oriented as desired, the process continues to step 230 where an error message is emitted to a central controller or operator. If the frame or ring 18a, 18b is oriented angularly relative to the pallet 20 as desired, the process continues to step 238 and the movable section of the conveyor 22 is lowered relative to the base 17. After the conveyor section has been lowered, the assembly process continues at the workstation while the controller 220 process ends at step 232. Alternatively, the sensors 224 can emit a signal corresponding to an image of the pallet 20 with associated rotatable frames or rings 18a, 18b and elements 28a-28f defining geometry fixtures. The controller 220 can compare the signal with data corresponding to an acceptable image stored in memory. If the signal does not correspond to the acceptable data image stored in memory, the controller 220 can emit a signal corresponding to an error message to a central controller or operator, and signal motor 114 to prevent lowering movement of the movable section of the conveyor 22 with respect to the base 17. When the movable section of the conveyor 22 is lowered at one of the workstations 14b-14f, the conveyor locating means 196 can engage the movable section of the conveyor 22. When the pallet 20 has been stopped at the receiving workstation 14b-14f, the movable section of the conveyor is activated to move from the raised position to the lowered position. The plate 204 connected to the transverse member 66g of the movable section of the conveyor 22 prevents downstream movement of the movable section of the conveyor 22 with respect to the flow of workpieces along the path of travel 12. The plate 204 and roller 248 prevent transverse movement and longitudinal movement of the movable section of the conveyor 22 in response to vertical rotary movement of the rollers 104a, 104b being converted into vertical linear movement of the movable section of the conveyor 22 and supported pallet 20. As the movable section of the conveyor 22 is lowered, the positioning means 16 can engage the pallet 20. The pin 156 can operably engages within the aperture 162 to accurately position the pallet 20 in a horizontal plane defined by horizontal axes extending longitudinally and transversely with respect to the path of travel 12. The guides 178a, 178d, and 178e can engage the horizontal frame member 36b to further locate and align the pallet 20 in a direction transverse to the path 12. The guides 178b, 178c, and 178f can engage the horizontal frame member 36a to limit transverse movement of the pallet with respect to the path of travel 12. Roller guiding means 164 can receive the guide member 172 connected to the pallet 20. The movable section of the conveyor 22 can be lowered relative to the base 17 at the receiving workstation 14b-14f in response to control signals generated by the controller 220. The controller 220 can control the motor 114 to rotate the shaft 118 and pulleys 120a, 120b. The pulleys 120a, 120b drive the belts 112, 122 to rotate pulleys 110a associated with the shafts 106, 106a. Rollers or cams mounted on crank arms at each end of shafts 106, 106a are rotated about the axis of rotation of the corresponding shaft. Rollers or cams 126a, 126b as shown in FIG. 10 are received within the elongate slot or apertures defined by brackets 92a-92d. The rollers engage the corresponding brackets to raise and lower the movable section of the conveyor 22. Preferably, the movable section of the conveyor 22 can be vertically moved approximately 75 millimeters relative to the base 17. When the movable section of the conveyor 22 is being lowered relative to base 17, an end 144 of the pin 50 can engage with the lock release actuator or key 142 causing the lock 48 to be moved from a locked position to an unlocked position. As the movable section of the conveyor 22 is being lowered, the gear teeth 32 of the rotatable frames or rings 18a, 18b engage gear teeth 140 of each gear 136 of the ring drivers 128a, 128b. The pin 50 and lock release actuator or key 142 are configured so that the lock 48 reaches the unlocked position only after the gear teeth 32 are in intermeshing engagement with the gear teeth 140 of the ring drivers 128a, 128b. When the movable section of the conveyor 22 is raised relative to the base 17, the lock 48 is moved to the locked position before the intermeshing gear teeth 32, 140 have completely disengaged. At the loading workstation 14b, after the movable section of the conveyor 22 has been lowered relative to the base 17, the individual components and/or sub-assemblies received from the one or more workstations 24a-24d can be loaded into the geometry fixture associated with the rotatable frame or rings 18a, 18b. It should be recognized that the lock 48 can be manipulated independently from positioning the pallet 20 and locating the movable section of the conveyor 22. The lock release actuator 142 and corresponding ring drives 128a, 128b are only required to be present at workstations that require, or are performing, a reorientation of the angular position of the rotatable frames or rings 18a, 18b with respect to the supporting pallet 20. If desired in a particular application, after the lock 42 has been moved to the unlocked position, and the teeth 32 and 140 have meshed, components and/or sub-assemblies can be loaded into the geometry fixtures carried by the rings 18a, 18b. If desired for a particular application, the rings 18a, 18b can be rotated to assist in the process of loading the components and/or sub-assemblies into the various elements 28a-28f of the geometry fixtures. After the sub-assemblies and/or components have been mounted in the individual elements 28a-28f defining the geometry fixture, the clamping or gripping elements can be operated by any suitable actuator system. The clamping and gripping elements defining the geometry fixtures associated with the rings 18a, 18b are maintained in a clamped or gripped position while the pallet 20 moves along the first portion 208 of the path of travel 12. After the sub-assemblies and/or components have been loaded within the geometry fixtures supported by the rotatable frames or rings 18a, 18b, and if required for a particular application, the rotatable frames or rings can be rotated independently of one another to a desired angular orientation relative to the pallet 20 by the motors 132 of the ring drivers 128a, 128b for further processing at the present workstations or at subsequent workstations. The controller 220 can independently control the motors 132 allowing for different angular movements by each rotatable frame or ring if desired. Position encoders can be associated with each motor 132 for signaling the angular position or orientation of each rotatable frame or ring. The controller 220 controls motor 114 to rotate the shaft 118 resulting in vertical movement of the movable section of the conveyor 22 relative to the base 17. The movable section of the conveyor 22 is raised in response to rotation of the shaft 118 by controller 220 when the frames or rings 18a, 18b have been loaded and/or rotated to a desired orientation relative to the pallet 20, and the pallet 20 is ready for delivery to the next workstation. After the conveyor section 20 has been raised relative to the base 17 at any one of the workstations 14b-14f, the pallet is ready to be moved toward the next workstation. Sensors 224 can emit a signal corresponding to the presence of the sub-assemblies and/or components in the elements 28a-28f forming the geometry fixtures, as well as the angular orientation of the rotatable frames or rings 18a, 18b relative to the pallet 20. The controller 220 can receive the signals from the sensors 224 and emit an error signal to a central control system or operator if the required sub-assemblies and/or components are not loaded with respect to the elements 28a-28f of the geometry fixtures, or if the rotatable frames or rings 18a, 18b are not in a desired angular orientation relative to the pallet 20. If the sub-assemblies and/or components are loaded as desired, and the rotatable frames or rings 18a, 18b are in a desired angular orientation, the controller 220 controls motor 84 to rotate the wheels 70a-70f and move the pallet 20 to a subsequent workstation. The first workstation 14c is positioned adjacent to and downstream of the loading workstation 14b along the path of travel 12. The workstation 14c can also include sensors 224 operable to emit a signal corresponding to the angular orientation of the rotatable frame or ring relative to the pallet 20 and the presence of sub-assemblies and/or components loaded with respect to the elements 28a-28f defining the particular geometry fixture. If the angular orientation of the rotatable frames or rings 18a, 18b is incorrect, the controller 220 can emit an error message to a central controller or operator. If the orientation of the rings 18a, 18b is in a desired orientation, the movable section of the conveyor 22 at the workstation 14c can be lowered by controller 220 actuating rotation of shaft 118 through motor 114. Referring now to FIGS. 18 and 19, the workstations 14c and 14d are first and second welding workstations, respectively for fixing the overall geometry of the workpiece held within the geometry fixtures associated with the rotatable frames or rings 18a, 18b. FIG. 19 schematically shows a first pallet 20 with rotatable frames or rings 18a, 18b at the first welding workstation 14c and a second pallet 20a with rotatable frames or rings 18c, 18d at the second welding workstation 14d. Sub-assemblies and/or components loaded with respect to the elements 28a-28f forming the geometry fixture can be welded at the first welding workstation 14c and the second welding workstation 14d. Each workstation can include one or more robots, such as robots 250a-250d positioned at workstation 14c, and robots 250e-250h positioned at workstations 14d. Robots 250a-250h can be welding robots. Each workstation can include four robots, two robots located on each side of the path of travel 12. The robots 250a and 250b, on a first side of the path of travel 12, can perform the identical weld passes with respect to the workpieces 11a, 11b held by the corresponding first and second rotatable frames or rings 18a, 18b located adjacent the respective robots when the pallet 20 is positioned at the workstation and the movable section of the conveyor is in the lowered position at the workstation. The robots 250c and 250d, on a second side of the path of travel 12, can perform identical weld passes on the two workpieces 11a, 11b carried by the pallet 20. Controller 220 can either control or interact with separate controllers for the robots 250a-250h to perform welding operations with respect to the individual workpieces 11a, 11b to be assembled. Robots 250e-250h can perform either identical weld passes as the robots 250a-250d, or can perform respot welding in areas inaccessible during the first welding passes. This may require a reorientation of the angular position of the rotatable frames or rings 18a, 18b at one of the workstations or at another workstation interposed between the illustrated workstations 14c, 14d. If any of the robots 250a-250d fails to perform a desired welding operation due to mechanical failure or scheduled maintenance, the controller 220 can detect such an error through appropriate signals received from each of the robots 250a-250d. The controller 220 can compensate for the detected error by instructing one or more of the robots downstream of the failed robot, such as robots 250d-250h at the workstation 14d, to perform the required weld passes that were not performed by the failed robot. If the lock release actuator 142 and ring drives 128a, 128b have been provided at each of the workstations, the rotatable frames or rings 18a, 18b can be rotated at any of the workstations between processing operations so that all welding is performed on an upwardly facing surface to allow easier access while improving quality and repeatability of the weld processing operations. These features provide greater flexibility, redundancy, and higher quality finished workpieces in the production line than previously provided in assembly lines for motorcycle frames. The controller 220 according to the present invention processes according to a control program stored in memory. The process begins after the workpieces supported by the pallet 20 are delivered to the movable section of the conveyor 22 and have been moved to the lowered position. T process is illustrated in the simplified flow diagram of FIG. 20. The process starts at step 252. Step 254 determines whether the required weld passes have been completed by the pair of robots located on each side of rotatable frames or rings 18a, 18b. By way of example and not limitation, robot 250a can make a particular weld pass with respect to the workpiece 11b mounted with respect to the ring 18b, and emit a signal to the controller 220 corresponding to completion of the particular weld pass. Robot 250d can perform a first weld pass with respect to the workpiece 11b and emit a signal to the controller 220 corresponding to completion of the first weld pass. After the controller 220 has received signals corresponding to completion of all the required weld passes from the robots 250a and 250d, step 256 determines if a reorientation of the angular position of the rotatable frame 18a, 18b is required, and if required, controller 220 actuates the appropriate motor to rotate the rotatable frame or ring 18a, 18b to a desired predetermined orientation relative to the pallet 20. By way of example and not limitation, the controller 220 can control the motor 132a to rotate the rotatable frame or ring 18b and position the workpiece 11b in a desired angular position with respect to the robots 250a and 250d. The rotatable frame or ring 18a, 18b can be rotated so that subsequent weld passes can be completed in a downward orientation (i.e. on an upwardly facing surface) with respect to the motorcycle frame as the welding process is completed. Step 258 determines if all of the required weld passes for the rotatable frame or ring have been completed. By way of example and not limitation, the controller 220 can store in memory data corresponding to the required weld passes to be performed by each robot 250a-250h and compare the signals received from each robot with the stored data as the required weld passes are completed by each robot. If all of the required weld passes have not been completed, the process returns to step 254. If the all of the required weld passes with respect to a particular workpiece carried by a particular rotatable frame or ring have been completed, step 260 determines whether all of the weld passes have been completed with respect to the other workpiece carried by the other rotatable frame or ring associated with the common pallet. The controller 220 can simultaneously monitor the completion of required weld passes with respect to the rotatable frames or rings 18a, 18b. When the required weld passes for the rotatable frames or rings 18a, 18b have been completed, step 262 raises the movable section of the conveyor 22 supporting the pallet 20. The motor 114 is controlled by controller 220 to rotate shaft 118 and vertically move the movable section of the conveyor 22 to the raised position. The process ends at step 264. After all the processing or welding operations at workstations 14c, 14d have been completed, the pallet 20 can be moved to workstations 14e, 14f, respectively, for further processing. Before the pallet 20 is moved from any of the workstations, corresponding sensors 224 positioned at each of the workstations emit signals to the controller 220 corresponding to the angular orientation of the rotatable frame or rings 18a, 18b with respect to the pallet 20. The controller 220 emits an error message to a central controller or operator, if any one of the rotatable frames or rings 18a, 18b is not in a desired angular orientation relative to the pallet 20. If an error signal is generated by the controller 220, continued movement of the pallets 20 along the path of travel 12 is stopped. By way of example and not limitation, processing operations at workstations 14e, 14f can include, but are not limited to, removal of the assembled workpieces 11a, 11b from the rotatable frames or rings 18a, 18b, inspection of the workpieces 11a, 11b, and/or finishing of the workpieces 11a, 11b. Workstations 14e, 14f can include sensors 224 in communication with the controller 220 and/or additional robots for automated processing. It should be recognized that only those workstations requiring accurate positioning and locating of the workpiece for automated processing will need all of the structure described with respect to base 17 for supporting a movable section of the conveyor 22 and/or accurately locating the movable section of conveyor 22 and/or accurately positioning the pallet 20 at the corresponding workstation. Manual loading/unloading workstations, or manual inspection workstations, or manual respot workstations can be provided with a simplified base for supporting the conveyor 22. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law. | <SOH> BACKGROUND OF THE INVENTION <EOH>The current assembly of motorcycle frames typically includes a primary work cell where several individual frame components are brought together and welded to one another. The current approach requires highly specialized work cells, each work cell dedicated to a particular frame configuration. Flexibility of the manufacturing process is limited. | <SOH> SUMMARY OF THE INVENTION <EOH>A method and apparatus according to the present invention conveys workpieces along a path of travel. The path of travel can be an assembly line for the assembly of motorcycle frames. A plurality of pallets are movable along the path of travel defined by the convey system of the assembly line. Each pallet supports at least one workpiece-supporting frame or ring. A plurality of differently configured workpieces can be supported for movement along the path of travel. The workpieces can form a motorcycle frame constructed from individual components positioned with respect to one another in the frame or ring. Each frame or ring has at least one geometry-locating fixture for supporting and locating individual components in predetermined positions with respect to one another. Each geometry-locating fixture is removably associated with the corresponding frame or ring to accommodate the plurality of differently configured workpieces. Each geometry-locating fixture can include one or more elements selected from clamps, pins, guides or any combination thereof. Each frame or ring can be individually rotated through a predetermined angular arc at one or more workstations positioned along the path of travel to reorient the angular position of the workpiece being constructed to a desired angular position with respect to the rotational axis during processing operations. By way of example and not limitation, a frame or ring can be rotated to reorient a workpiece in an inverted orientation, so that a welding robot can perform a welding operation from above for easier access. Each frame or ring can be conveyed along the path of travel by pallets carried along a conveyor located at, above, or below, the manufacturing floor depending on the particular application and plant layout. Each pallet can rotatably support one or more frames or rings. Each pallet can include a lock to prevent movement of the associated frame or ring during movement of the pallet along the path of travel. The individual pallets can be moved along the conveyor defining the path of travel. The conveyor can extend along the path of travel between and through one or more workstations. The reorientation of the angular position of the frame or ring and the associated workpiece being constructed can be performed by bringing the pallet and an associated lock into operable engagement with a lock release and a motor or drive for rotating the frame or ring about an axis of rotation. By way of example and not limitation, the conveyor can be divided into individual sections, where some conveyor sections can be vertically moveable with respect to the path of travel for raising and lowering a pallet and associated workpiece carried thereon with respect to the workstation. For purposes of illustration, when a particular conveyor section is moved vertically, either raised or lowered relative to the workstation, the associated frames or rings can engage one or more motors for rotating the associated frames or rings with respect to the pallet. Rotation of each frame or ring results in reorientation of the associated workpiece being constructed into a desired position of angular orientation with respect to the axis of rotation. When properly oriented for the next processing operation, the pallet can be returned by lowering or raising the particular conveyor section, to the original position for delivery to the next workstation. Alternatively, the motor and lock release can be moved relative to the conveyor and/or pallet between an engaged position for reorienting the workpiece and a disengaged position allowing delivery and removal of the pallets along the conveyor. Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings. | 20050118 | 20070123 | 20050609 | 83690.0 | 0 | OMGBA, ESSAMA | METHOD FOR ASSEMBLY OF A MOTORCYCLE FRAME | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,037,800 | ACCEPTED | Method and device to clamp control lines to tubulars | The inventions relates to an apparatus for connecting a control line to a tubular string. In one embodiment, the apparatus includes a guide boom pivotable around a location adjacent the string and with a guide member at an end thereof to guide the control line. The apparatus further includes a clamp boom that is independently pivotable and includes a clamp housing at an end thereof for clamping the control line against the tubular string. The guide boom and the clamp boom each have a center line which is substantially aligned with the center line of the tubing string permitting the control line to be aligned adjacent the tubular string prior to clamping. | 1. A control line positioning apparatus comprising: a control line holding assembly movable between a staging position and a clamping position; a mounting assembly for connecting the control line holding assembly to a rig structure, the rig structure having a rig floor and the mounting assembly located substantially adjacent the rig floor; a motive member for moving the control line holding assembly between the staging position and the clamping position; and an arm for connecting the control line holding assembly to the mounting assembly, wherein the arm extends at an angle relative to the rig floor when the control line holding assembly is in the clamping position. 2. The apparatus of claim 1, wherein the angle relative is greater than 30 degrees. 3. The apparatus of claim 1, wherein the mounting assembly is connected to the rig floor. 4. The apparatus of claim 1, further including a clamp holding assembly movable between a second staging position and a second clamping position. 5. The apparatus of claim 4, further including a second motive member for moving the clamp holding assembly between the second staging position and the second clamping position. 6. The apparatus of claim 5, wherein the second motive member is a fluid operated cylinder. 7. The apparatus of claim 4, wherein the clamp holding assembly is movable independently of the control line holding assembly. 8. The apparatus of claim 4, further including a second arm for connecting the clamp holding assembly to the mounting assembly. 9. The apparatus of claim 8, wherein the second arm extends at an angle relative to the rig floor. 10. The apparatus of claim 9, wherein the second arm is moveable through an arc describing at least 100 degrees. 11. The apparatus of claim 4, further including a clamp for securing the control line to a tubular string. 12. The apparatus of claim 8, wherein the second arm is extendable independent of the first arm. 13. The apparatus of claim 1, wherein the rig structure includes a well center and the apparatus is arranged and configured such that the mounting assembly is closer to the well center than the control line holding assembly when the control line holding assembly is in the staging position. 14. The apparatus of claim 1, wherein a movement of the control line holding assembly describes an arc that substantially intersects with a center line of a tubular string. 15. The apparatus of claim 1, wherein the control line holding assembly is constructed and arranged to position the control line substantially parallel with a tubular string. 16. The apparatus of claim 1, wherein the motive member is a fluid cylinder. 17. A method of operating a control line positioning apparatus comprising: moving a control line holding assembly from a staging position to a clamping position, wherein the control line holding assembly is operatively mounted proximate a floor of a rig with a mounting assembly; holding a control line adjacent a tubular string with the control line holding assembly; securing the control line to the tubular string; and relocating the control line holding assembly away from the tubular string. 18. The method of claim 17, wherein the control line holding assembly and the mounting assembly are connected by an arm that extends at an angle relative to the rig floor. 19. The method of claim 17, further including a clamp holding assembly. 20. The method of claim 19, further including moving the clamp holding assembly through an arc describing at least 100 degrees. 21. The method of claim 19, wherein the clamp holding assembly is attached to the rig floor by a second arm. 21. The method of claim 21, further including extending the second arm relative to the first arm. 22. The method of claim 17, wherein the clamp holding assembly includes a clamp. 23. The method of claim 22, further including positioning the clamp over a coupling in the tubular string. 24. The method of claim 17, further including sensing an operative condition of at least one other tubular handling device of the rig and controlling the control line holding assembly in response to the sensed operative condition. 25. The method of claim 24, wherein the controlling is achieved by automatic feedback of the sensed operative condition into a control system. 26. The method of claim 17, further including sensing an operative condition of the control line holding assembly and controlling at least one other tubular handling device of the rig in response to the sensed operative condition. 27. The method of claim 26, wherein the controlling is achieved by automatic feedback of the sensed operative condition into a control system. 28. A method for running a well pipe into a well with control lines attached to the pipe, comprising: securing a pipe with a spider located above a rig floor; providing a control line alignment apparatus having a mounting member, a control line engagement member and a motive member for moving the engagement member relative to the mounting member; using the control line alignment apparatus to align the control line with the pipe at a location below the spider and above the rig floor; securing the control line to the pipe below the spider; and lowering the pipe and secured control line into the well. 29. The method of claim 28, wherein the control alignment apparatus further includes an arm for connecting the control arm engagement member to the mounting member. 30. The method of claim 29, wherein the arm is angled at least 45 degrees relative to the rig floor. 31. The method of claim 30, wherein the control alignment apparatus further includes a clamp holder assembly for securing the control line to the well pipe. 32. The method of claim 31, further including rotating the clamp holder through an arc describing at least 100 degrees. 33. A method of aligning a control line with a tubular, comprising: positioning a control line using a remotely controllable head; determining a position of the head, wherein the position of the head aligns a first portion of the control line with a tubular string; memorizing the position of the head; and positioning a second portion of the control line using the memorized position. 34. The method of claim 33, wherein the remotely controllable head is attached to a rig floor by an arm that extends at an angle relative to the rig floor. 35. The method of claim 34, wherein the angle relative is at least 45 degrees. 36. The method of claim 33, further including securing the control line to the tubular. 37. An apparatus for positioning a control line adjacent a tubular string, the apparatus comprising: a guide boom pivotable around a location adjacent the tubular string, the boom including a guide member at an end thereof to guide the control line; and a clamp boom independently pivotable from substantially the same location as the guide boom, the clamp boom having a clamp assembly at an end thereof for clamping the line against the tubular. | CROSS-REFERENCE TO RELATED APPLICATIONS This application claims benefit of U.S. provisional patent application Ser. No. 60/536,800, filed Jan. 15, 2004. This application is also a continuation-in-part of co-pending U.S. patent application Ser. No. 10/625,840, filed Jul. 23, 2003, which is a continuation of application Ser. No. 09/860,127, filed on May 17, 2001, now U.S. Pat. No. 6,742,596. This application is also a continuation-in-part of co-pending U.S. patent application Ser. No. 10/611,565, filed Jul. 1, 2003, which is a continuation of application Ser. No. 09/486,901, filed on May 19, 2000, now U.S. Pat. No. 6,591,471, filed as U.S.C. § 371 of International Application No. PCT/GB98/02582, filed Sep. 2, 1998 which claims priority to GB 9718543.3, filed on Sep. 2, 1997. Each of the aforementioned related Patents and patent applications is herein incorporated by reference in its entirety. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the makeup of tubular strings at the surface of a well. More particularly, the invention relates to making up strings and running the strings into the well along with a control line or signal transmission line. More particularly still, the invention relates to methods and apparatus for facilitating the clamping of a control line or signal transmission line to a tubular string prior to lowering the string, clamp, and such line into the well. 2. Description of the Related Art Strings of pipe are typically run into a wellbore at various times during the formation and completion of a well. A wellbore is formed for example, by running a bit on the end of the tubular string of drill pipe. Later, larger diameter pipe is run into the wellbore and cemented therein to line the well and isolate certain parts of the wellbore from other parts. Smaller diameter tubular strings are then run through the lined wellbore either to form a new length of wellbore therebelow, to carry tools in the well, or to serve as a conduit for hydrocarbons gathered from the well during production. As stated above, tools and other devices are routinely run into the wellbore on tubular strings for remote operation or communication. Some of these are operated mechanically by causing one part to move relative to another. Others are operated using natural forces like differentials between downhole pressure and atmospheric pressure. Others are operated hydraulically by adding pressure to a column of fluid in the tubular above the tool. Still others need a control line to provide either a signal, power, or both in order to operate the device or to serve as a conduit for communications between the device and the surface of the well. Control lines (also known as umbilical cords) can provide electrical, hydraulic, or fiber optic means of signal transmission, control and power. Because the interior of a tubular string must be kept clear for fluids and other devices, control lines are often run into the well along an outer surface of the tubular string. For example, a tubular string may be formed at the surface of a well and, as it is inserted into the wellbore, a control line may be inserted into the wellbore adjacent the tubular string. The control line is typically provided from a reel or spool somewhere near the surface of the well and extends along the string to some component disposed in the string. Because of the harsh conditions and non-uniform surfaces in the wellbore, control lines are typically fixed to a tubular string along their length to keep the line and the tubular string together and prevent the control line from being damaged or pulled away from the tubular string during its trip into the well. Control lines are typically attached to the tubular strings using clamps placed at predetermined intervals along the tubular string by an operator. Because various pieces of equipment at and above well center are necessary to build a tubular string and the control line is being fed from a remotely located reel, getting the control line close enough to the tubular string to successfully clamp it prior to entering the wellbore is a challenge. In one prior art solution, a separate device with an extendable member is used to urge the control line towards the tubular string as it comes off the reel. Such a device is typically fixed to the derrick structure at the approximate height of intended engagement with a tubular traversing the well center, the device being fixed at a significant distance from the well center. The device is telescopically moved toward and away from well center when operative and inoperative respectively. The device must necessarily span a fair distance as it telescopes from its out of the way mounting location to well center. Because of that the control line-engaging portion of the device is difficult to locate precisely at well center. The result is often a misalignment between the continuous control line and the tubular string making it necessary for an operator to manhandle the control line to a position adjacent the tubular before it can be clamped. There is a need therefore for an apparatus which facilitates the clamping of the control line to a tubular string at the surface of a well. There is additionally a need for an apparatus which will help ensure that a control line is parallel to the center line of a tubular string as the control line and the tubular string come together for clamping. SUMMARY OF THE INVENTION In one embodiment, the apparatus includes a guide boom pivotable around a location adjacent the string and with a guide member at an end thereof to guide the control line. The apparatus further includes a clamp boom that is independently pivotable and includes a clamp housing at an end thereof for carrying and locating a clamp to clamp the control line against the tubular string. The guide boom structure and the clamp boom structure each have a center line which is substantially aligned with the center line of the tubing string permitting the control line to be aligned adjacent the tubular string prior to clamping. In another embodiment, the method includes locating a guide boom at a location adjacent the tubular string, wherein the guide boom includes a guide member at an end thereof to guide the line. The method further includes locating a clamp boom at a location adjacent the tubular string, wherein the clamp boom includes a removable clamp. Additionally, the method includes clamping the line to the tubular string by utilizing the clamp and relocating the booms to a location away from the tubular string while leaving the line clamped to the tubular string. BRIEF DESCRIPTION OF THE DRAWINGS So that the manner in which the above recited features can be understood in detail, a more particular description is briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments and are therefore not to be considered limiting of scope, for the invention may admit to other equally effective embodiments. FIG. 1 illustrates one embodiment of an assembly used to facilitate the clamping of a control line to a tubular string. FIG. 2 illustrates the assembly of FIG. 1 in a position whereby the control line has been brought to a location adjacent the tubular string for the installation of a clamp. FIG. 3 is a detailed view of the clamp. FIG. 4 illustrates another embodiment of an assembly used to facilitate the clamping of the control line to tubular string. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates one embodiment of an assembly 100 used to facilitate the clamping of a control line 300 to a tubular string 105. The assembly 100 is movable between a staging position and a clamping position. As shown, the assembly 100 is located adjacent the surface of a well 110. Extending from the well 110 is the tubular string 105 comprising a first 112 and a second 115 tubulars connected by a coupling 120. Not visible in FIG. 1 is a spider which consists of slips that retain the weight of the tubular string 105 at the surface of the well 110. Also not shown in the Figure is an elevator or a spider which would typically be located above the rig floor or work surface to carry the weight of the tubular 112 as it is aligned and threadedly connected to the upper most tubular 115 to increase the length of tubular string 105. The general use of spiders and elevators to assemble strings of tubulars is well known and is shown in U.S. Publication No. US-2002/0170720-A1, which is incorporated herein by reference. The assembly 100 includes a guide boom 200 or arm, which in one embodiment is a telescopic member made up of an upper 201 and a lower 202 boom. Guide boom 200 is mounted on a base 210 or mounting assembly at a pivot point 205. Typically, the guide boom 200 extends at an angle relative to the base 210, such as an angle greater than 30 degrees. A pair of fluid cylinders 215 or motive members permits the guide boom 200 to move in an arcuate pattern around the pivot point 205. Visible in FIG. 1 is a spatial relationship between the base 210 and a platform table 130. Using a fixing means, such as pins 150, the base 210 is fixed relative to the table 130, thereby permitting the guide boom 200 to be fixed relative to the tubular string 105 extending from the well 110 and preferably the guide boom 200 is fixed relatively proximate the tubular string 105 or well center. In this fashion, the vertical center line of the guide boom 200 is substantially aligned with the vertical center line of the tubular string 105, ensuring that as the guide boom 200 pivots around the pivot point 205 to approach the tubular string 105 (see FIG. 2) and subsequently causing the path of the boom 200 and the tubular string 105 to reliably intersect. This helps ensure that the control line 300 is close enough to the string 105 for a clamp 275 to be manually closed around the string 105 as described below. As shown in FIG. 1, a guide 220 or a control line holding assembly is disposed at an upper end of guide boom 200. The guide boom 220 has a pair of rollers 222 mounted therein in a manner which permits the control line 300 to extend through the rollers 222. Generally, the control line 300 is supplied from a reel (not shown) which is located proximate the guide boom 200 but far enough from the center of the well 110 to avoid interfering with the spider, elevator or draw works associated with the tubular string 105. The control line 300 can provide power or signals or both in any number of ways to a component or other device disposed in the well 110. Reels used to supply control lines are well known in the art and are typically pre-tensioned, whereby the control line will move off the reel as it is urged away from the reel while permitting the reel to keep some tension on the line and avoiding unnecessary slack. Also visible in FIG. 1 is a clamp boom 250 or arm, which in one embodiment is a telescopic member made up of an upper 251 and a lower 252 boom. The clamp boom 250 is mounted substantially parallel to the guide boom 200. The clamp boom 250 includes a pivot point 255 adjacent the pivot point 205 of guide boom 200. The clamp boom 250 is moved by one or more fluid cylinders. For instance, a pair of fluid cylinders 260 moves the clamp boom 250 around the pivot point 255 away from the guide boom 200. Another fluid cylinder 265 causes the clamp boom 250 to lengthen or shorten in a telescopic fashion. Since the clamp boom 250 is arranged similarly to the guide boom 200, the clamp boom 250 also shares a center line with the tubular string 105. As defined herein, a fluid cylinder may be hydraulic or pneumatic. Alternatively, the booms 200, 250 may be moved by another form of a motive member such as a linear actuator, an electric or fluid operated motor or any other suitable means known in the art. As shown in FIG. 1, a clamp holding assembly comprising a clamp housing 270 and a removable clamp 275 is disposed at an end of the clamp boom 250. The removable clamp 276 includes a first clamp member 280 and a second clamp member 281 which are designed to reach substantially around and embrace a tubular member, clamping, or securing a control line together with the tubular member. More specifically, the clamp 275 is designed to straddle the coupling 120 between two tubulars 112, 115 in the tubular string 105. For example, in the embodiment of FIG. 1, the clamp 275 is designed whereby one clamp member 281 will close around the lower end of tubular 112 and another clamp member 280 will close around an upper end of tubular 115, thereby straddling coupling 120. A frame portion between the clamp members 280, 281 covers the coupling 120. The result is a clamping arrangement securing the control line 300 to the tubular string 105 and providing protection to the control line 300 in the area of coupling 120. A more detailed view of the clamp 275 is shown in FIG. 3. In the preferred embodiment, the clamp 275 is temporarily held in the clamp housing 270 and then is releasable therefrom. FIG. 2 illustrates the assembly 100 in a position adjacent the tubular string 105 with the clamp 275 ready to engage the tubular string 105. Comparing the position of the assembly 100 in FIG. 2 with its position in FIG. 1, the guide boom 200 and the clamp boom 250 have both been moved in an arcuate motion around pivot point 205 by the action of fluid cylinders 215. Additionally, the cylinders 260 have urged the clamp boom 250 to pivot around the pivot point 255. The fluid cylinder 265 remains substantially in the same position as in FIG. 1, but as is apparent in FIG. 2, could be adjusted to ensure that coupling 120 is successfully straddled by the clamp 275 and that clamp members 280, 281 can be secured around tubulars 112 and 115, respectively. In FIG. 2, the guide 220 is in close contact with or touching tubular 112 to ensure that the control line 300 is running parallel and adjacent the tubular string 105 as the clamp boom 250 sets up the clamp 275 for installation. The quantity of control line 300 necessary to assume the position of FIG. 2 is removed from the pretensioned reel as previously described. Still referring to FIG. 2, the clamp boom 250 is typically positioned close to the tubular string 105 by manipulating fluid cylinders 260 until the clamp members 280, 281 of the clamp 275 can be manually closed by an operator around tubulars 112 and 115. Thereafter, the clamp 275 is removed from the housing 270 either manually or by automated means and the assembly 100 can be retracted back to the position of FIG. 1. It should be noted that any number of clamps can be installed on the tubular string 105 using the assembly 100 and the clamps do not necessarily have to straddle a coupling. In operation, the tubular string 105 is made at the surface of the well with subsequent pieces of tubular being connected together utilizing a coupling. Once a “joint” or connection between two tubulars is made, the string 105 is ready to be lowered into the wellbore to a point where a subsequent joint can be assembled. At that point, the guide boom 200 and the clamp boom 250 of the present invention are moved in an arcuate motion bringing the control line 300 into close contact and alignment with the tubular string 105. Thereafter, the cylinders 260 operating the clamp boom 250 are manipulated to ensure that the clamp 275 is close enough to the tubular string 105 to permit its closure by an operator and/or to ensure that the clamp members 280, 281 of the clamp 275 straddle the coupling 120 between the tubulars. After the assembly 100 is positioned to associate the clamp 275 with tubular string 105, an operator closes the clamp members 280, 281 around the tubulars 112, 115 and thereby clamps the control line 300 to the tubulars 112, 115 in such a way that it is held fast and also protected, especially in the area of the coupling 120. Thereafter, the assembly 100 including the guide boom 200 and the clamp boom 250 is retracted along the same path to assume a retracted position like the one shown in FIG. 1. The tubular string 105 can now be lowered into the wellbore along with the control line 300 and another clamp can be loaded into the clamp housing 270. In one embodiment, the guide boom and the clamp boom fluid cylinders are equipped with position sensors which are connected to a safety interlock system such that the spider can not be opened unless the guide boom 200 and the clamp boom 250 are in the retracted position. Alternatively such an interlock system may sense the proximity of the guide boom and clamp boom to the well center for example by either by monitoring the angular displacement of the booms with respect to the pivot points or by a proximity sensor mounted in the control line holding assembly or the clamp holding assembly to measure actual proximity of the booms to the tubular string. Regardless of the sensing mechanism used the sensor is in communication with the spider and/or elevator (or other tubular handling device) control system so that one of the spider or elevator must be engaged with the tubular (i.e. it is locked out from release) in order for the guide or clamp boom to approach the tubular and such a lock out remains until both guide and clamp booms are withdrawn. Such an interlock system may also include the rig draw works controls. It is desirable that the tubular string not be raised or lowered while the control line or clamp booms are adjacent the string. The aforementioned boom position sensing mechanisms can be arranged to send signals (e.g. fluidic, electric, optic, sonic, or electromagnetic) to the draw works control system thereby locking the draw works (for example by locking the draw works brake mechanism in an activated position) when either the control line or clamp booms are in an operative position. Some specific mechanisms that may be used to interlock various tubular handling components and rig devices are described in U.S. Publication No. US-2004/00069500 and U.S. Pat. No. 6,742,596 which are incorporated herein in their entirety by reference. FIG. 4 illustrates another embodiment of an assembly 500 used to facilitate the clamping of the control line 300 to the tubular string 115. For convenience, the components in the assembly 400 that are similar to the components in the assembly 100 will be labeled with the same number indicator. As illustrated, the assembly 400 includes a guide boom 500. The guide boom 500 operates in a similar manner as the guide boom 200 of assembly 100. However, as shown in FIG. 4, the guide boom 500 has a first boom 505 and a second boom 510 that are connected at an upper end thereof by a member 515. The member 515 supports the guide 220 at an end of the guide boom 500. Additionally, the guide boom 500 is mounted on the base 210 at pivot points 520. Similar to assembly 100, the pair of fluid cylinders 215 permits the guide boom 500 to move in an arcuate pattern around pivot points 520. In one embodiment, each boom 505, 510 may include an upper and a lower boom which are telescopically related to each other to allow the guide boom 500 to be extended and retracted in a telescopic manner. Also visible in FIG. 4 is a clamp boom 550, which in one embodiment is a telescopic member made from an upper and a lower boom. The clamp boom 550 extends at an angle relative to the base 210 and is movable at least 100 degrees. The clamp boom 550 is mounted between the booms 505, 510 of the guide boom 500. The clamp boom 550 having a pivot point (not shown) adjacent the pivot points 520 of guide boom 500. Typically, the clamp boom 550 is manipulated by a plurality of fluid cylinders. For instance, a pair of fluid cylinders (not shown) causes the clamp boom 550 to move around the pivot point. Another fluid cylinder 265 causes the clamp boom 550 to lengthen or shorten in a telescopic fashion. The clamp boom 550 is positioned adjacent the tubular string 105 so that the clamp boom 550 shares a center line with the tubular string 105. In a similar manner as the clamp boom 250 in assembly 100, the clamp boom 550 includes the clamp assembly comprising the clamp housing 270 and the removable clamp 270 disposed at an end thereof. Similar to the operation of assembly 100, the guide boom 500 and the clamp boom 550 of the assembly 400 are moved in an arcuate motion bringing the control line 300 into close contact and alignment with the tubular string 105. Thereafter, the cylinders 260 operating the clamp boom 550 are manipulated to ensure that the clamp 275 is close enough to the tubular string 105 to permit its closure by an operator. After the assembly 400 is positioned adjacent the tubular string 105, the operator closes the clamp 275 around the tubular string 105 and thereby clamps the control line 300 to the tubular string 105 in such a way that it is held fast and also protected, especially if the clamp 275 straddles a coupling in the tubular string 105. Thereafter, the clamp boom 550 may be moved away from the control line 300 through a space defined by the booms 505, 510 of the guide boom 500 to a position that is a safe distance away from the tubular string 105 so that another clamp 275 can be loaded into the clamp housing 270. The manipulation of either assembly 100 or assembly 400 may be done manually through a control panel 410 (shown on FIG. 4), a remote control console or by any other means know in the art. The general use of a remote control console is shown in U.S. Publication No. US-2004/0035587-A1, which has been incorporated herein by reference. In one embodiment a remote console (not shown) may be provided with a user interface such as a joystick which may be spring biased to a central (neutral) position. When the operator displaces the joystick, a valve assembly (not shown) controls the flow of fluid to the appropriate fluid cylinder. As soon as the joystick is released, the appropriate boom stops in the position which it has obtained. The assembly 100, 400 typically includes sensing devices for sensing the position of the boom. In particular, a linear transducer is incorporated in the various fluid cylinders that manipulate the booms. The linear transducers provide a signal indicative of the extension of the fluid cylinders which is transmitted to the operator's console. In operation, the booms (remotely controllable heads) are moved in an arcuate motion bringing the control line into close contact and alignment with the tubular string. Thereafter, the cylinders operating the clamp boom are further manipulated to ensure that the clamp is close enough to the tubular string to permit the closure of the clamp. When the assembly is positioned adjacent the tubular string, the operator presses a button marked “memorize” on the console. The clamp is then closed around the tubular string to secure the control line to the tubular string. Thereafter, the clamp boom and/or the guide boom are retracted along the same path to assume a retracted position. The tubular string can now be lowered into the wellbore along with the control line and another clamp can be loaded into the clamp housing. After another the clamp is loaded in the clamp housing, the operator can simply press a button on the console marked “recall” and the clamp boom and/or guide boom immediately moves to their memorized position. This is accomplished by a control system (not shown) which manipulates the fluid cylinders until the signals from their respective linear transducers equal the signals memorized. The operator then checks the alignment of the clamp in relation to the tubular string. If they are correctly aligned, the clamp is closed around the tubular string. If they are not correctly aligned, the operator can make the necessary correction by moving the joystick on his console. When the booms are correctly aligned the operator can, if he chooses, update the memorized position. However, this step may be omitted if the operator believes that the deviation is due to the tubular not being straight. While the foregoing embodiments contemplate fluid control with a manual user interface (i.e. joy stick) it will be appreciated that the control mechanism and user interface may vary without departing from relevant aspects of the inventions herein. Control may equally be facilitated by use of linear or rotary electric motors. The user interface may be a computer and may in fact include a computer program having an automation algorithm. Such a program may automatically set the initial boom location parameters using boom position sensor data as previously discussed herein. The algorithm may further calculate boom operational and staging position requirements based on sensor data from the other tubular handling equipment and thereby such a computer could control the safety interlocking functions of the tubular handling equipment and the properly synchronized operation of such equipment including the control line and clamp booms. The aforementioned safety interlock and position memory features can be integrated such that the booms may automatically recall their previously set position unless a signal from the tubular handling equipment (e.g. spider/elevator, draw works) indicates that a reference piece of handling equipment is not properly engaged with the tubular. While the assembly is shown being used with a rig having a spider in the rig floor, it is equally useful in situations when the spider is elevated above the rig floor for permit greater access to the tubular string being inserted into the well. In those instances, the assembly could be mounted on any surface adjacent to the tubular string. The general use of such an elevated spider is shown in U.S. Patent Applicant No. 6,131,664, which is incorporated herein by reference. As shown in FIG. 1 of the '664 patent, the spider is located on a floor above the rig floor that is supported by two vertical wall members. In this arrangement, the apparatus could be mounted on the underside of the floor supporting the spider or on one of the adjacent walls. Various modifications to the embodiments described are envisaged. For example, the positioning of the clamp boom to a predetermined location for loading a clamp into the clamp housing could be highly automated with minimal visual verification. Additionally, as described herein, the position of the booms is memorized electronically, however, the position of the booms could also be memorized mechanically or optically. While the foregoing is directed to embodiments other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to the makeup of tubular strings at the surface of a well. More particularly, the invention relates to making up strings and running the strings into the well along with a control line or signal transmission line. More particularly still, the invention relates to methods and apparatus for facilitating the clamping of a control line or signal transmission line to a tubular string prior to lowering the string, clamp, and such line into the well. 2. Description of the Related Art Strings of pipe are typically run into a wellbore at various times during the formation and completion of a well. A wellbore is formed for example, by running a bit on the end of the tubular string of drill pipe. Later, larger diameter pipe is run into the wellbore and cemented therein to line the well and isolate certain parts of the wellbore from other parts. Smaller diameter tubular strings are then run through the lined wellbore either to form a new length of wellbore therebelow, to carry tools in the well, or to serve as a conduit for hydrocarbons gathered from the well during production. As stated above, tools and other devices are routinely run into the wellbore on tubular strings for remote operation or communication. Some of these are operated mechanically by causing one part to move relative to another. Others are operated using natural forces like differentials between downhole pressure and atmospheric pressure. Others are operated hydraulically by adding pressure to a column of fluid in the tubular above the tool. Still others need a control line to provide either a signal, power, or both in order to operate the device or to serve as a conduit for communications between the device and the surface of the well. Control lines (also known as umbilical cords) can provide electrical, hydraulic, or fiber optic means of signal transmission, control and power. Because the interior of a tubular string must be kept clear for fluids and other devices, control lines are often run into the well along an outer surface of the tubular string. For example, a tubular string may be formed at the surface of a well and, as it is inserted into the wellbore, a control line may be inserted into the wellbore adjacent the tubular string. The control line is typically provided from a reel or spool somewhere near the surface of the well and extends along the string to some component disposed in the string. Because of the harsh conditions and non-uniform surfaces in the wellbore, control lines are typically fixed to a tubular string along their length to keep the line and the tubular string together and prevent the control line from being damaged or pulled away from the tubular string during its trip into the well. Control lines are typically attached to the tubular strings using clamps placed at predetermined intervals along the tubular string by an operator. Because various pieces of equipment at and above well center are necessary to build a tubular string and the control line is being fed from a remotely located reel, getting the control line close enough to the tubular string to successfully clamp it prior to entering the wellbore is a challenge. In one prior art solution, a separate device with an extendable member is used to urge the control line towards the tubular string as it comes off the reel. Such a device is typically fixed to the derrick structure at the approximate height of intended engagement with a tubular traversing the well center, the device being fixed at a significant distance from the well center. The device is telescopically moved toward and away from well center when operative and inoperative respectively. The device must necessarily span a fair distance as it telescopes from its out of the way mounting location to well center. Because of that the control line-engaging portion of the device is difficult to locate precisely at well center. The result is often a misalignment between the continuous control line and the tubular string making it necessary for an operator to manhandle the control line to a position adjacent the tubular before it can be clamped. There is a need therefore for an apparatus which facilitates the clamping of the control line to a tubular string at the surface of a well. There is additionally a need for an apparatus which will help ensure that a control line is parallel to the center line of a tubular string as the control line and the tubular string come together for clamping. | <SOH> SUMMARY OF THE INVENTION <EOH>In one embodiment, the apparatus includes a guide boom pivotable around a location adjacent the string and with a guide member at an end thereof to guide the control line. The apparatus further includes a clamp boom that is independently pivotable and includes a clamp housing at an end thereof for carrying and locating a clamp to clamp the control line against the tubular string. The guide boom structure and the clamp boom structure each have a center line which is substantially aligned with the center line of the tubing string permitting the control line to be aligned adjacent the tubular string prior to clamping. In another embodiment, the method includes locating a guide boom at a location adjacent the tubular string, wherein the guide boom includes a guide member at an end thereof to guide the line. The method further includes locating a clamp boom at a location adjacent the tubular string, wherein the clamp boom includes a removable clamp. Additionally, the method includes clamping the line to the tubular string by utilizing the clamp and relocating the booms to a location away from the tubular string while leaving the line clamped to the tubular string. | 20050118 | 20070731 | 20050728 | 67634.0 | 1 | BATES, ZAKIYA W | METHOD AND DEVICE TO CLAMP CONTROL LINES TO TUBULARS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,037,802 | ACCEPTED | Tail configuration for an artificial fishing lure | A fishing lure generally includes a body and a body extension member that extends rearwardly from the body. The body may be in the form of a grub or worm, and the body extension member may be in the form of a tail that extends from the rearward end of the body. Alternatively, the body may be in the form of a crayfish and a pair of body extension members, in the form of arms, may extend from the rearward end of the body. The body extension member includes first, second, and third portions. The first portion extends away from the body, and the second portion connects to the first portion. The third portion connects to the second portion and extends generally toward the body. The third portion includes a forwardly facing inner edge that may be linear, and the first and third portions preferably cooperate to form an acute angle. | 1. A fishing lure comprising: a. a body; and b. a body extension member including a first portion that is interconnected with and extends away from the body, a second portion that is connected to the first portion, and a third portion that is connected to the second portion and that extends generally in a direction toward the body, wherein the third portion includes a substantially linear inner edge that faces the first portion of the body extension member. 2. The fishing lure of claim 1, wherein the first portion and the third portion define facing edges that cooperate to form an acute angle. 3. The fishing lure of claim 2, wherein the acute angle is an angle of between about 15 degrees and about 35 degrees. 4. The fishing lure of claim 3, wherein the acute angle is an angle of about 25 degrees. 5. The fishing lure of claim 1, wherein the body includes ribs that extend laterally along the body. 6. The fishing lure of claim 1, wherein the second portion of the body extension member has a curved outer edge. 7. The fishing lure of claim 1, wherein the body comprises an axially extending member and wherein the body extension member comprises a tail member that extends from a rearward end of the axially extending member, wherein the tail includes a first portion having a first thickness and a second portion having a second thickness that is lesser than the first thickness. 8. The fishing lure of claim 7, wherein the first portion includes first and second outer edges, each of which tapers inwardly and an inner edge that has a C-shape. 9. The fishing lure of claim 1, wherein the body is in a form resembling a crayfish, and wherein the body extension member comprises a pair of arm members that extend from the body at opposite sides defined by the body. 10. The fishing lure of claim 1, wherein the body extension member defines a pair of flat, outwardly facing surfaces that face in opposite directions, wherein the outwardly facing surfaces include beveled outer edges that intersect each other to form an outer rim of the body extension member. 11. A fishing lure comprising: a. a body; and b. a body extension member including a first portion that is interconnected with and extends away from the body, a second portion that is connected to the first portion, and a third portion that is connected to the second portion and that extends generally toward the body, wherein the first portion and the third portion define facing edges that cooperate to define an acute angle. 12. The fishing lure of claim 11, wherein the facing edges defined by the first and third portions are substantially linear. 13. The fishing lure of claim 11, wherein the acute angle is an angle of between about 15 degrees and about 35 degrees. 14. The fishing lure of claim 13, wherein the acute angle is an angle of about 25 degrees. 15. The fishing lure of claim 11, wherein the body includes ribs that extend laterally along the body. 16. The fishing lure of claim 11, wherein the second portion of the body extension member has a curved outer edge. 17. The fishing lure of claim 11, wherein a rear end of the body defines a decreasing thickness in an outward direction. 18. The fishing lure of claim 17, wherein the rear end of the body includes first and second outer edges, each of which tapers inwardly and an inner edge that has a C-shape. 19. The fishing lure of claim 11, wherein the body extension member includes a pair of body extension members that extend rearwardly from opposite sides defined by the body. 20. The fishing lure of claim 11, wherein the body extension member defines a pair of flat, outwardly facing surfaces that face in opposite directions, wherein the outwardly facing surfaces include beveled outer edges that intersect each other to form an outer rim of the body extension member. 21. An artificial fishing lure, comprising: a body defining a forward end and a rearward end; and a body extension member extending from the rearward end of the body, wherein the body extension member includes a laterally offset section that defines an exposed, forwardly facing edge, wherein the body extension member is configured such that the forwardly facing edge catches the water as the artificial fishing lure is pulled through the water to impart a side-to-side motion for the body extension member. 22. The artificial fishing lure of claim 21, wherein the body extension member includes an inner portion that is interconnected with the body, wherein the inner portion defines an first edge that cooperates with the forwardly facing edge of the laterally offset section to generally define an acute angle. 23. The artificial fishing lure of claim 22, wherein the forwardly facing edge of the laterally offset section is generally linear. 24. The artificial fishing lure of claim 22, wherein the body extension member is configured to define a second edge spaced from the first edge, wherein the second edge is configured to cooperate with the forwardly facing edge of the laterally offset section intersect to define a point of intersection therebetween. 25. The artificial fishing lure of claim 24, wherein the second edge of the body extension member is generally arcuate, wherein the body extension member comprises a first portion defined between the first and second edges of the body extension member, a generally flat second portion located rearwardly of the first portion, and a third portion defined by the between the second edge and the forwardly facing edge that extends generally forwardly relative to the second portion, wherein the third portion and an area of the second portion are configured to define the laterally offset section of the body extension member. 26. The artificial fishing lure of claim 25, wherein the body extension member has a thickness less than that of the body and includes a pair of generally flat, oppositely facing surfaces. 27. The artificial fishing lure of claim 25, wherein the body extension member comprises a tail section that extends from the rearward end of the body. 28. The artificial fishing lure of claim 25, wherein a pair of body extension members extend rearwardly from opposite sides defined by the body toward the rearward end of the body. | BACKGROUND AND SUMMARY OF THE INVENTION The invention relates to a fishing lure, and more particularly to an artificial fishing lure which acts to simulate live bait movement. Artificial fishing lures are typically designed to resemble or otherwise imitate live bait. Soft plastic artificial fishing lures are commonly configured to resemble worms, bugs or small fish. A drawback to many types of soft plastic fishing lures is that the lure tends to exhibit unnatural movements, or movements that are otherwise not attractive to fish, when traveling through the water. Many attempts have been made to provide artificial fishing lures that more closely replicate live bait movement, or that otherwise exhibit action that is attractive to fish. A common attempt includes the provision of a tail, which causes the lure to move when the lure is pulled through the water by a fishing line. In a representative prior art construction, the tail extends out from a body of the fishing lure at a rear end of the lure, opposite the fishing line. The conventional tail has a flat, curved end that defines a J-shape. The tail flutters slightly and imparts slight movement to the body when the lure is pulled through the water. However, these types of tails are relatively limp and generally do not provide the desired strong movements that are known to attract fish. Therefore, it is a primary object and feature of the present invention to provide a fishing lure that simulates live bait movement. It is a further object and feature of the present invention to provide a fishing lure that provides vigorous action that is attractive to fish. It is a further object and feature of the present invention to provide a fishing lure having a design that resembles the appearance of live bait while providing unique movement and action as the fishing lure is pulled through the water. In accordance with the present invention, a fishing lure generally includes a body and a body extension member, which may be in the form of a tail. The body extension member includes first, second, and third portions. The first portion extends away from the body, and the second portion is connected to an outer end defined by the first portion. The third portion is connected to the second portion, and extends generally toward the body. The third portion includes a generally linear inner edge, and the first and third portions are preferably configured to form an acute angle. The linear edge of the body extension member catches the water as the lure is pulled through the water, and the configuration of the body extension member provides vigorous movement of the body extension member as well as the body, that is attractive to fish. Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS The drawings illustrate the best mode presently contemplated of carrying out the invention. In the drawings: FIG. 1 is a side elevation view of an artificial fishing lure incorporating a body extension member, in the form of a tail, in accordance with the present invention, showing the artificial lure at rest; FIG. 2 is a partial top plan view of the artificial fishing lure or FIG. 1, showing the lure in a first position during movement of the lure through the water; FIG. 3 is a partial side elevation view of the artificial fishing lure in the position of FIG. 2; FIG. 4 is a sectional view through line 4-4 of FIG. 3; FIG. 5 is a partial top plan view of the artificial fishing lure of FIG. 1, showing the lure in a second position during movement of the lure through the water; FIG. 6 is a partial side elevation view of the artificial fishing lure in the position of FIG. 5; FIG. 7 is a sectional view through line 7-7 of FIG. 6; FIG. 8 is a partial top plan view of the artificial fishing lure of FIG. 1, showing the lure in a third position during movement through the water; FIG. 9 is a partial side elevation view of the artificial lure in the position of FIG. 8; FIG. 10 is a sectional view through line 10-10 of FIG. 9; FIG. 11 is a partial top plan view of the artificial fishing lure of FIG. 1, showing the lure in a fourth position during movement through the water; FIG. 12 is a partial side elevation view of the artificial lure in the position of FIG. 11; FIG. 13 is a sectional view through line 13-13 of FIG. 12; FIG. 14 is a partial top plan view of the artificial fishing lure of FIG. 1, showing the lure in a fifth position during movement through the water; FIG. 15 is a partial side elevation view of the artificial lure in the position of FIG. 14; FIG. 16 is a sectional view through line 16-16 of FIG. 15; and FIG. 17 is a view similar to FIG. 1, showing an alternative embodiment of a fishing lure incorporating a body extension member constructed according to the present invention. DETAILED DESCRIPTION OF THE INVENTION A first preferred embodiment of a fishing lure 10 includes a body 12 and a body extension member in the form of a tail 14, as is shown in FIG. 1. For the sake of reference only, the fishing lure 10 and its various parts will be described as having a front end and a rear end. The front end is the end of the fishing lure that is typically attached to a fishing line. In the illustrated embodiment, the body 12 has a shape generally resembling that of a grub, and includes ribs 16 that extend around the body 12 along its length. The body 12 defines a front end 18, at which a fishing line 20 can be connected via a hook 24, in a manner as is known, and a rear end 22 from which the tail 14 extends. The body 12 is dimensioned and configured such that a fishing hook 24 can be inserted into the front end 14 of the body 12 and out of a side of the body 12. In the illustrated embodiment, the body 12 has a generally cylindrical shape, and the front and rear ends 18 and 22 are tapered. The body also defines a front side 26 and an oppositely facing rear side (not shown). On both its front side 26 and rear side, the rear end 22 of the body 12 includes a first portion 30 having a first thickness and a second portion 32 having a second thickness that is less than the first thickness. The first portion 30 is disposed outwardly from the second portion 32. The first portion 30 includes first and second outer surfaces 34 and 36, each of which tapers inwardly, and an inner edge 38, which is C-shaped. With this construction, second portion 32 generally defines a dimple that is located rearwardly of edge 38 defined by first portion 30. The tail 14 includes a front side 40 and a rear side 42, which define outer edges 44 and 46, respectively, that are tapered such that one edge meets the other at an outer rim 48 of the tail 14. The tail 14 also includes a front end 50, at which the tail 14 connects to the body 12, and a rear end 52, which is free and which curves outwardly. The tail 14 also includes a first portion 56, a second portion 64, and a third portion 70. The first portion 56 extends away from the body 12 and includes a forward end 60 and a rearward end 62. The second portion 64 includes a forward end 66 and a rearward end 68. A section of the forward end 66 connects to the rearward end 62 of the first portion 56. The rearward end 68 of the second portion 64 defines the free end of tail 14. The third portion 70 includes a rearward end 72 and a forward end 74. The rearward end 72 of the third portion 70 connects to a section of the rearward end 68 of the second portion 64. The forward end 74 of the third portion 70 extends generally forwardly toward the body 12. The forward end 74 of the third portion 70 includes a substantially linear inner edge 76 and a curved outer edge 78 that cooperate to form a point 79 therebetween. In a preferred version of the fishing lure 10, the first portion 56 and the third portion 70 are configured to form an acute angle α between linear edge 76 of third portion 70 and the facing edge of first portion 56, shown at 81. Preferably, the acute angle α is an angle of between about 15 degrees and about 35 degrees. More preferably, the acute angle α is an angle of about 25 degrees. While the specific disclosure of fishing lure 10 contained herein shows facing edges 76 and 81 as being linear, it is understood that edges 76 and 81 may have a non-linear configuration. For example, and without limitation, edges 76 and 81 may have a linear, concave or convex configuration or any combination thereof, so long as edges 76 and 81 are formed so as to define a definite point of intersection therebetween. As shown in the drawings, first portion 56 and the area of second portion 64 in alignment with first portion 56 extend along an axis in a rearward direction from the rear end of body 12. Third portion 70 and the area of second portion 64 in alignment with third portion 70 are laterally offset from the axis of first portion 56, which provides the twisting motion of tail 14 as fishing lure 10 is pulled through the water. Preferably, the fishing lure 10 is made from a resilient soft plastic material in a manner as is known in the art, or from any other material that is attractive to fish and provides the fishing lure 10 with the ability to flex and twist. In use, a hook 24 is inserted through the front end 18 of the body 12 and out of a side of the body 12. The fishing lure 10 is cast into a body of water and is reeled back toward the user, in a known manner. As fishing lure 10 is reeled in, the structure of the fishing lure 10 imparts movement to fishing lure 10 that has been found to be attractive to fish. FIGS. 2-16 show the action of fishing lure 10 during movement through the water, which occurs as lure 10 is being reeled in. Initially, when fishing lure 10 is first cast out, tail 14 assumes an at-rest position in which first portion 56, second portion 64 and third portion 70 are generally coplanar as shown in FIGS. 8-10. As fishing lure 10 is moved in an axial direction through the water, the inner edge 76 of third portion 70 catches the water and initiates a twisting motion of tail 14. Such movement of tail 14 first involves outward movement of third portion 70 in one direction, which representatively may be in the direction of arrow 84 (FIG. 5), although initial outward movement of third portion 70 may also be in the opposition direction. As tail 14 is moved outwardly in this manner, the entire area of tail 14 rearwardly of first portion 56 is shifted laterally or transversely in the direction of arrow 84 as shown in FIGS. 5-7, and the exposure of inner edge 76 to the water then imparts a twisting motion which causes tail 14 to twist and results in tail 14 moving from the position as shown in FIGS. 2-4 toward the position as shown in FIGS. 2-4. Such twisting of tail 14 results from the water impinging upon inner edge 76 and the surface of third portion 70, which is offset from the longitudinal center of tail 14. Ultimately, such movement of tail 14 results in tail 14 reaching the position of FIGS. 2-4, wherein third portion 70 is moved outwardly in one direction relative to the longitudinal center of tail 14 and second portion 64 is moved outwardly in the opposite direction. When tail 14 is in this position, the surface area of second portion 64 that is exposed to the water exceeds that of third portion 70, which causes second portion 64 and third portion 70 to return toward the longitudinal center of tail 14, in the direction of arrow 86 (FIG. 5). Tail 14 is then moved to the position as shown in FIGS. 8-10, in which the various portions of tail 14 are in alignment and extend in a coplanar manner rearwardly from body 12. Continued movement of fishing lure 19 results in tail 14 moving in the opposite direction as shown by arrow 88 (FIG. 11), in which the entire area of tail 14 rearwardly of first portion 56 is shifted laterally or transversely in the direction of arrow 88 (opposite the direction of arrow 84 in FIG. 5), and the exposure of inner edge 76 to the water then imparts a twisting motion which causes tail 14 to twist in the opposite direction and results in tail 14 moving from the position as shown in FIGS. 11-13 toward the position as shown in FIGS. 14-16. As before, such twisting of tail 14 results from the water impinging upon inner edge 76 and the opposite surface of third portion 70, which is offset from the longitudinal center of tail 14. Ultimately, such movement of tail 14 results in tail 14 reaching the position of FIGS. 11-14, wherein third portion 70 is moved outwardly in one direction relative to the longitudinal center of tail 14 and second portion 64 is moved outwardly in the opposite direction. Again, when tail 14 is in this position, the surface area of second portion 64 that is exposed to the water exceeds that of third portion 70, which causes second portion 64 and third portion 70 to return toward the longitudinal center of tail 14, in the direction of arrow 90 (FIG. 11). Tail 14 is then moved to the position as shown in FIGS. 8-10, in which the various portions of tail 14 are in alignment and extend in a coplanar manner rearwardly from body 12, and tail 14 continues to move back and forth in this manner as long as fishing lure 10 is moved through the water. It can be appreciated that tail 14 moves in a side-to-side manner with strong, high frequency movement, to provide action that is attractive to fish. In addition, it can be appreciated that movement of tail 14 also imparts side-to-side movement to body 12 by virtue of the connection of tail 14 to body 12 and the resilient nature of the material of body 12, to further enhance the attractiveness of lure 10 to fish during movement through the water. While body 12 is shown and described as having a length that resembles that of a grub, it is also contemplated that body 12 may be formed so as to have a longer length to resemble a worm. In addition, while body 12 is shown and described as having ribs 16, it is also understood that body 12 may be smooth or may have any other surface pattern as desired. In addition, while movement of fishing lure 10 is shown and described as being in a side-to side manner, it is also understood that movement of tail 14 of fishing lure 10 may be in an up-and-down manner. FIG. 17 illustrates an alternative artificial fishing lure, shown at 100, incorporating a pair of body extension members in accordance with the present invention. In this embodiment, fishing lure 100 is in a form that generally resembles a crayfish, including a body 102 having a series of legs 104. A pair of body extension members, in the form of arms 106 that generally resemble claws, extend from the rearward end of body 102. Each arm 106 includes a connector section 108 that extends from body 102, and end structure 110 is connected to the outer end of connector section 108. End structure 110 is constructed identically to tail 14 of fishing lure 10, including first portion 56, second portion 64 and third portion 70. In this embodiment, end structure 110 functions to impart strong up-and-down or side-to-side movements to arms 106, which results in twisting of body 102 about its longitudinal axis. Legs 104 are resilient, such that the twisting of body 102 imparts a wave-like motion to legs 104. Such vigorous motion of body 102, legs 104 and arms 106 functions to attract fish as fishing lure 100 is pulled through the water. While the body extension member of the present invention has been shown and described in connection with two specific lure configurations, it is understood that the body extension member may be used in connection with artificial fishing lures of virtually any configuration. In addition, it is understood that the end structure of the body extension member may be located at the end of any type of fishing lure body or any other member that extends from a fishing lure body. Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention. | <SOH> BACKGROUND AND SUMMARY OF THE INVENTION <EOH>The invention relates to a fishing lure, and more particularly to an artificial fishing lure which acts to simulate live bait movement. Artificial fishing lures are typically designed to resemble or otherwise imitate live bait. Soft plastic artificial fishing lures are commonly configured to resemble worms, bugs or small fish. A drawback to many types of soft plastic fishing lures is that the lure tends to exhibit unnatural movements, or movements that are otherwise not attractive to fish, when traveling through the water. Many attempts have been made to provide artificial fishing lures that more closely replicate live bait movement, or that otherwise exhibit action that is attractive to fish. A common attempt includes the provision of a tail, which causes the lure to move when the lure is pulled through the water by a fishing line. In a representative prior art construction, the tail extends out from a body of the fishing lure at a rear end of the lure, opposite the fishing line. The conventional tail has a flat, curved end that defines a J-shape. The tail flutters slightly and imparts slight movement to the body when the lure is pulled through the water. However, these types of tails are relatively limp and generally do not provide the desired strong movements that are known to attract fish. Therefore, it is a primary object and feature of the present invention to provide a fishing lure that simulates live bait movement. It is a further object and feature of the present invention to provide a fishing lure that provides vigorous action that is attractive to fish. It is a further object and feature of the present invention to provide a fishing lure having a design that resembles the appearance of live bait while providing unique movement and action as the fishing lure is pulled through the water. In accordance with the present invention, a fishing lure generally includes a body and a body extension member, which may be in the form of a tail. The body extension member includes first, second, and third portions. The first portion extends away from the body, and the second portion is connected to an outer end defined by the first portion. The third portion is connected to the second portion, and extends generally toward the body. The third portion includes a generally linear inner edge, and the first and third portions are preferably configured to form an acute angle. The linear edge of the body extension member catches the water as the lure is pulled through the water, and the configuration of the body extension member provides vigorous movement of the body extension member as well as the body, that is attractive to fish. Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. | <SOH> BACKGROUND AND SUMMARY OF THE INVENTION <EOH>The invention relates to a fishing lure, and more particularly to an artificial fishing lure which acts to simulate live bait movement. Artificial fishing lures are typically designed to resemble or otherwise imitate live bait. Soft plastic artificial fishing lures are commonly configured to resemble worms, bugs or small fish. A drawback to many types of soft plastic fishing lures is that the lure tends to exhibit unnatural movements, or movements that are otherwise not attractive to fish, when traveling through the water. Many attempts have been made to provide artificial fishing lures that more closely replicate live bait movement, or that otherwise exhibit action that is attractive to fish. A common attempt includes the provision of a tail, which causes the lure to move when the lure is pulled through the water by a fishing line. In a representative prior art construction, the tail extends out from a body of the fishing lure at a rear end of the lure, opposite the fishing line. The conventional tail has a flat, curved end that defines a J-shape. The tail flutters slightly and imparts slight movement to the body when the lure is pulled through the water. However, these types of tails are relatively limp and generally do not provide the desired strong movements that are known to attract fish. Therefore, it is a primary object and feature of the present invention to provide a fishing lure that simulates live bait movement. It is a further object and feature of the present invention to provide a fishing lure that provides vigorous action that is attractive to fish. It is a further object and feature of the present invention to provide a fishing lure having a design that resembles the appearance of live bait while providing unique movement and action as the fishing lure is pulled through the water. In accordance with the present invention, a fishing lure generally includes a body and a body extension member, which may be in the form of a tail. The body extension member includes first, second, and third portions. The first portion extends away from the body, and the second portion is connected to an outer end defined by the first portion. The third portion is connected to the second portion, and extends generally toward the body. The third portion includes a generally linear inner edge, and the first and third portions are preferably configured to form an acute angle. The linear edge of the body extension member catches the water as the lure is pulled through the water, and the configuration of the body extension member provides vigorous movement of the body extension member as well as the body, that is attractive to fish. Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. | 20050117 | 20070130 | 20050609 | 95688.0 | 2 | ARK, DARREN W | TAIL CONFIGURATION FOR AN ARTIFICIAL FISHING LURE | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,037,883 | ACCEPTED | Base, payload and connecting structure and methods of making the same | Micromachined passive alignment assemblies and methods of using and making the same are provided. The alignment assemblies are used to align at least one optical element. The alignment assemblies may be configured with kinematic, pseudo-kinematic, redundant or degenerate support structures. One alignment assembly comprises a base and a payload, which supports at least one optical element. The payload may be coupled to the base via connecting structures. The base, the payload and/or the connecting structures may have internal flexure assemblies for preloading a connection, thermal compensation and/or strain isolation. | 1-64. (canceled) 65. An assembly configured to support at least one optical element to a pre-determined position, the assembly comprising: an optical element having three protrusions, each protrusion having four sidewalls, each sidewall being substantially perpendicular to a plane of the optical element, each protrusion having a sidewall facing a center point of the first micromachined structure; and; a micromachined structure having three grooves, the grooves being configured to contact the protrusions to restrain the micromachined structure with respect to the optical element in six degrees-of-freedom (DOFs), the optical element supported at a pre-determined position. | INCORPORATIONS BY REFERENCE Co-assigned U.S. patent application Ser. No. 09/855,305, entitled “Angled Fiber Termination And Methods Of Making The Same” (Attorney Docket No. M-11564 US), filed on May 15, 2001, is hereby incorporated by reference in its entirety. Another co-assigned U.S. patent application Ser. No. 10/001092, entitled “Optical Element Support Structure And Methods Of Using And Making The Same” (Attorney Docket No. M-11130 US), filed on Nov. 15, 2001, is hereby incorporated by reference in its entirety. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to optical devices, and more particularly to optical element alignment assemblies and methods of making the same. 2. Description of the Related Art An optical component, such as a mirror, lens or fiber, in an optical instrument or device, such as an optical switch, should be accurately located/positioned with respect to another optical component in order for the optical instrument or device to function properly. Thus, optical devices may require their components to be placed with exacting tolerances to fulfill design objectives. Conventional passive alignment assemblies for MicroElectroMechanical System (MEMS) devices are typically planar in nature and only align local elements, e.g., a fiber and ball lens collimator, where the two components are within a few millimeters of each other. Alignments over larger distances (e.g., greater than five millimeters), and three-dimensional optical systems typically use conventionally machined components. Such assemblies often fail to align optical components with high intrinsic precision. SUMMARY OF THE INVENTION Components generally need to be located in three dimensions, i.e., distributed in a volume of space, and have three rotations specified and/or controlled. Components located in a plane (two dimensions) with three or fewer rotations specified and/or controlled are a subset of the general case. Other design objectives may include: (1) locate components without induced strains, either from the process of mounting or through bulk temperature changes of constituent parts, and/or (2) support components as rigidly as possible. In accordance with the present invention, alignment assemblies and methods of using and making the assemblies are provided. An important advantage of several embodiments of the invention is to completely orient one body with respect to another body to a high degree of precision by providing (1) precise mating features between bodies and connecting elements, and (2) precise distances between these features on all bodies and connecting elements. In one embodiment, the alignment assemblies are passive, kinematic or non-kinematic, and micromachined. “Passive alignment” means the various parts or devices to be assembled have mating features such that when these features are engaged with each other, the correct alignment (typically optical) is attained. In some instances, the engagement of these mating features permanently controls the alignment. In other instances, some type of fixture will hold the parts with their mating features engaged while some additional fixation, e.g., glue or bolt, is added to make the engagement permanent. For comparison, in “active” alignment, two parts or devices are maneuvered with respect to each other by some motion control mechanism, e.g., a motorized motion stage, shim set, etc., in one or more directions or degrees-of-freedom (DOF) until some metric, e.g., light through-put, optical beam quality, etc., is within a specified tolerance. At that point, the two parts are fixed rigidly with respect to each other by some means, e.g., glue, solder, bolt. As defined and used herein, “kinematic mounting” relates to attaching two bodies, which may be called a base assembly or a payload assembly, together by forming a structural path and creating stiffness between the two bodies in six, and only six, independent degrees of freedom (“DOFs”) or directions. Each degree of freedom (DOF) kinematically controlled between two bodies is also a position defined, i.e., a specific value of that DOF, as a linear measurement, may be maintained. Six DOFs are desired because the location of any object in space is defined by three orthogonal coordinates, and the attitude of the object is defined by three orthogonal rotations. A kinematic support has the advantage of being stiff, yet any strains or distortions in the base assembly are not communicated to the payload assembly. Thus, any sensitive optical alignments are not altered in the payload assembly if the base assembly undergoes deformation due to applied loads or bulk temperature changes. In one embodiment, it is desirable to tailor a DOF based on the configuration of a “pseudo-kinematic” support. “Pseudo-kinematic” means that although there may be many DOFs connecting at least two bodies, such as two micromachined passive alignment assemblies, in a practical attachment scheme, the DOFs can be tailored such that only six DOFs have a relatively high stiffness, and substantially all other DOFs have a relatively low stiffness. Thus, true “kinematic” support means only 6 stiff DOFs connecting two parts, and no other stiffness paths exist. “Pseudo-kinematic” means there are 6 DOFs with relatively high stiffness, and possibly many more with much lower stiffness (typically two to three orders of magnitude less). In some applications, it is desirable to have pseudo-kinematic DOFs with relatively low stiffness to be two to three orders of magnitude lower than DOFs with relatively high stiffness. DOFs with different levels of stiffness may be accomplished using a flexure system to relieve stiffness in unwanted DOFs. Depending on the cross-sectional properties of elements in the flexure system, connecting elements between two bodies may attain the desired stiffness connectivities. The alignment assemblies and methods of making the assemblies according to the invention may provide a number of advantages. For example, the micromachined passive alignment assemblies may be made with high intrinsic precision. Micromachining processes may form three-dimensional structures from a substrate wafer with high accuracy. In several embodiments, one micromachined passive alignment assembly may be oriented and spaced with respect to another assembly (e.g., with connecting elements) with lithographic precision, e.g., three-dimensional translational positioning to less than one micron and three-dimensional angular positioning to less than five arcseconds for an assembly with a 50-mm characteristic dimension. The methods according to the invention may construct mating surfaces on micromachined passive alignment assemblies, such as a base assembly and a payload assembly, to control six independent DOFs between the assemblies and allow complete, high-precision specification of position and attitude. In some applications, it is desirable to have micromachined connecting elements with counterpart mating surfaces to mate with the mating surfaces on the base and payload assemblies. The accuracy of micromachined passive alignment assemblies may be fully realized if there is a positive contact between a pair of mating features. Thus, some form of preload or force may be applied to maintain compressive contact between the pair of mating features. An external force may be applied to preload mating surfaces to contact each other prior to gluing. Glues that shrink on cure may be used to maintain the preload across mating surfaces after assembly. In addition to or instead of an external force, any of the structural elements being assembled may have an internal flexure assembly that applies an intemally-reacted force (preload). The internal flexure assembly may seat mating surfaces without a deadband. In one embodiment, the internal flexure assembly comprises a set of double parallel motion flexures, a preloader stage, and a hole on one side of the preloader stage for inserting a separate preloader pin. When the preloader pin is inserted into the hole of the internal flexure assembly, the preloader stage deflects and exerts a force on the pin, which exerts a preload against a mating surface. After the micromachined passive alignment assemblies are assembled, the mating surfaces may be glued or bonded if desired. A connecting element may be configured to restrain the base assembly and the payload assembly with one or more desired DOFs. In some embodiments, a “degenerate” support or connecting element may be used where less than six constrained DOFs between a base and payload are desired. The degenerate support may allow some trajectory (i.e., a combination of Cartesian DOFs) of a payload assembly relative to a base assembly to be unconstrained. A “redundant” support or connecting element may be used in applications where more than six DOFs are desired. The redundant support reinforces the base and payload assemblies and maintains their flatness. As another example, a micromachined passive alignment assembly may have thermal compensation flexure assemblies for maintaining centration of optical elements in the presence of large bulk or local temperature differences. The optical elements may then be attached to at least three pads supported by these flexure assemblies to effect this stable positioning. In some applications, it is desirable to position a plurality of optical elements in a precise pattern in the presence of large bulk or local temperature differences. In some of these applications, it may be desirable to position a plurality of thermal compensation flexure assemblies concentric with respect to the center of an opening and equidistant with respect to each other. One aspect of the invention relates to an assembly configured to support at least one optical element to a pre-determined position. The assembly comprises a first micromachined structure having at least a first mating part and a second micromachined structure having at least a second mating part. The second mating part is configured to contact the first mating part to constrain the second micromachined structure with respect to the first micromachined structure. The second micromachined structure is configured to support at least one optical element. In one embodiment, the second mating part is configured to contact the first mating part to precisely position the second micromachined structure with respect to the first micromachined structure. In one embodiment, the optical element is then precisely positioned with respect to the first micromachined structure. In one embodiment, the first micromachined structure also supports one or more optical elements. Another aspect of the invention relates to an assembly configured to support at least one optical element. The assembly comprises a first micromachined structure having at least a first attachment point and a second micromachined structure having at least a second attachment point. The second attachment point is configured to contact the first attachment point to restrain the second micromachined structure with respect to the first micromachined structure in at least one degree-of-freedom (DOF). The second micromachined structure is configured to support at least one optical element at a pre-determined position. In one embodiment, the second attachment point is configured to contact the first attachment point to restrain and align the second micromachined structure with respect to the first micromachined structure. In one embodiment, the optical element is then aligned to a pre-determined position with respect to the first micromachined structure. In one embodiment, the first micromachined structure also supports one or more optical elements. Another aspect of the invention relates to a method of making an assembly configured to position an optical element to a pre-determined position. The method comprises using lithography to form a first pattern and a second pattern on a substrate for a first structure and a second structure. The first pattern outlines a first mating part of the first structure. The second pattern outlines a second mating part of the second structure. The method comprises etching the substrate to form the first and second structures according to the first and second patterns. The second mating part is configured to contact the first mating part to constrain the second structure with respect to the first structure. The second structure is configured to position at least one optical element. One aspect of the invention relates to an assembly configured to support at least one optical element to a pre-determined position. The assembly comprises a micromachined base, a payload and a connecting structure. The base has a first mating part. The payload is configured to position the optical element. The payload has a second mating part. The connecting structure is configured to contact the first mating part of the base and the second mating part of the payload. The connecting structure constrains the payload in about five to about six degrees of freedom with respect to the base. In one embodiment, the base also positions an optical element. Another aspect of the invention relates to an assembly configured to position at least one optical element to a pre-determined position. The assembly comprises a base plate and at least one side plate configured to connect to the base plate. The base plate and the side plate are configured to support a plurality of payload plates. Each payload plate is configured to connect to the side plate and to the base plate. Each payload plate is configured to position at least one optical element. Another aspect of the invention relates to a method of making an assembly configured to position at least one optical element to a pre-determined position. The method comprises using lithography to form a first pattern, a second pattern and a third pattern on a substrate for a base, a payload and a connecting structure. The first pattern outlines a first mating part of the base. The second pattern outlines a second mating part of the payload. The third pattern outlines third and fourth mating parts of the connecting structure. The method further comprises etching the substrate to form the base, the payload and the connecting structure according to the first, second and third patterns. The connecting structure is configured to contact the first mating part of the base and the second mating part of the payload. The connecting structure constrains the payload in about five to about six degrees of freedom with respect to the base. The payload is configured to position an optical element. One aspect of the invention relates to a micromachined flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of parallel motion flexures and a preloader stage coupled to the set of parallel motion flexures. The set of parallel motion flexures allows the preloader stage to deflect away from a second structure of the optical element alignment assembly and apply a load against the second structure to constrain the second structure in at least one degree of freedom with respect to the first structure. Another aspect of the invention relates to a micromachined thermal compensation flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of collinear flexures and a center stage coupled to the set of collinear flexures. The set of collinear flexures and the center stage are configured to limit distortions in one direction due to a temperature change in the first structure from affecting an optical element supported by the first structure. In one embodiment, three or more such assemblies may completely support a second structure, e.g., an optical element or assembly, with respect to the first structure such that there are minimal internal stresses, and hence distortions, in the second structure in the presence of bulk temperature changes or substantial temperature differences between the structures. Another aspect of the invention relates to a micromachined strain isolation flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of collinear flexures and a center stage coupled to the set of collinear flexures. The set of collinear flexures and the center stage are configured to limit strains in one direction in the first structure from transferring to a second structure. Three or more such assemblies may completely isolate a second structure, e.g., an optical element or assembly, with respect to the first structure such that there are minimal internal stresses, and hence distortions, in the second structure in the presence of mechanically or inertially induced distortions in the first structure. Another aspect of the invention relates to a method of making a micromachined flexure assembly in a structure that is a part of an optical element alignment assembly. The method comprises using lithography to form a pattern on a substrate for the structure. The pattern outlines a set of collinear flexures and a center stage coupled to the set of collinear flexures. The method further comprises etching the substrate to form the structure according to the pattern. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a three-dimensional view of one kinematic support configuration. FIG. 1B is a three-dimensional view of another kinematic support configuration. FIG. 2A is a side view of a monopod connecting element shown in FIG. 1A. FIG. 2B is a side view of a bipod connecting element shown in FIG. 1B. FIG. 3 is a three-dimensional view of one embodiment of a slip-fit joint assembly. FIG. 4 is a three-dimensional view of another embodiment of a slip-fit joint assembly. FIG. 5 is a three-dimensional view of one embodiment of a stiffness control flexure system and an attachment portion. FIG. 6 is a three-dimensional view of one embodiment of a pseudo-kinematic bipod connecting element. FIG. 7 illustrates an example of positional control using the pseudo-kinematic bipod connecting element in FIG. 6 attached to a base assembly and a payload assembly. FIG. 8 is a side view of one embodiment of an internal flexure assembly. FIG. 9 illustrates two examples of preloading using a tab and slot attachment scheme with the internal flexure assembly of FIG. 8. FIG. 10 is a three-dimensional view of one embodiment of a preloader pin. FIG. 11 illustrates an example where a plurality of internal flexure assemblies are used to maintain contact at mating surfaces of a slot. FIG. 12A is a three-dimensional enlarged view of one embodiment of a fiber termination array assembly. FIG. 12B is a three-dimensional assembled view of the fiber termination array assembly in FIG. 12A. FIG. 13 is a side view of two embodiments of redundant connecting elements. FIG. 14 is a three-dimensional view of the two redundant connecting elements and the plate of FIG. 13. FIG. 15 is a three-dimensional view of one embodiment of a pseudo-kinematic support system. FIG. 16 is a three-dimensional view of one embodiment of a partially-degenerate support system. FIG. 17 is a three-dimensional view of another embodiment of a partially-degenerate support system. FIG. 18 is a three-dimensional view of one embodiment of a strain isolation flexure assembly. FIG. 19 is a three-dimensional view of one embodiment of a thermal compensation flexure assembly. FIG. 20 is a three-dimensional view of one embodiment of a micromachined passive alignment assembly with a plurality of chucks in the base assembly and payload assembly for aligning optical elements. FIG. 21 is an enlarged three-dimensional view of one part of the micromachined alignment assembly in FIG. 20. FIG. 22 is a three-dimensional view of one embodiment of an assembly, which comprises a first structure, a plurality of connecting elements and a second structure. FIG. 23 is an enlarged view of a redundant attachment point of one connecting element in FIG. 22. FIG. 24 is an enlarged view of a pseudo-kinematic attachment point of one connecting element in FIG. 22. FIG. 25 is a three-dimensional view of one embodiment of a megastack structure. FIG. 26 is an enlarged view of some attachment points of the side plate and the base plate in FIG. 25. FIG. 27 is the top view of the megastack structure in FIG. 25. FIG. 28 is a side view of one embodiment of a side plate in FIG. 25. FIG. 29 is a three-dimensional view of a complete megastack structure, which is shown partially in FIG. 25. FIG. 30 is the three-dimensional bottom view of the megastack structure in FIG. 29. FIG. 31 illustrates one method of designing the three-dimensional structures and assemblies described above and translating the designs into masks for high precision microlithography/photolithography. FIG. 32 illustrates one method of making high precision, three-dimensional structures described above. FIG. 33 illustrates one method of assembling three-dimensional structures described above from planar parts. DETAILED DESCRIPTION FIG. 1A is a three-dimensional schematic view of one kinematic support configuration 100A. The kinematic support configuration 100A in FIG. 1A comprises a base assembly 102, a payload assembly 104 and six monopod connecting elements 106A-106F (individually or collectively referred to herein as “monopod connecting element 106”). In one configuration, the base assembly 102 is a base support structure, and the payload assembly 104 holds or aligns an optical element, such as an optical fiber, lens or mirror. The base assembly 102 is connected to the payload assembly 104 via the six monopod connecting elements 106A-106F. Each monopod connecting element 106 in FIG. 1A constrains one degree of freedom (hereinafter referred to as ‘DOF’) between the base assembly 102 and the payload assembly 104, as shown by an arrow above the kinematic support configuration 100A in FIG. 1A. A constrained DOF may be referred to as a ‘stiff’ DOF or a restrained DOF. The relevant reference parameter for translational stiffness or translational DOF is force, while the relevant reference parameter for rotational stiffness or rotational DOF is torque. FIG. 1B is a three-dimensional schematic view of another kinematic support configuration 100B. The kinematic support configuration 100B in FIG. 1B comprises a base assembly 102, a payload assembly 102 and three bipod connecting elements 108A-108C (individually or collectively referred to herein as “bipod connecting element 108”). The base assembly 102 is connected to the payload assembly 104 via the three bipod connecting elements 108A-108C. Each bipod connecting element 108 constrains two DOFs between the base assembly 102 and the payload assembly 104, as shown by a pair of arrows near the kinematic support configuration 100B in FIG. 1B. In one embodiment, the kinematic support configurations 100A, 100B each have a structural path between the base assembly 102 and the payload assembly 104 in six independent DOFs, as shown by the arrows in FIGS. 1A, 1B. Six DOFs of constraint may be desired for some optic alignment applications. The kinematic support configurations 100A, 100B in FIGS. 1A and 1B have the advantage of being as stiff as the connecting elements 106A-106F, 108A-108C, but any strain or distortion in the base assembly 102 will not be transferred to the payload assembly 104 (although a positional or attitude change may occur). Thus, any sensitive optical elements aligned within the payload assembly 104 will not be affected if applied loads or bulk temperature changes deform the base assembly 102. Similarly, if the payload 104 grows or shrinks, there will be no forces transferred to the base assembly 102 because of the connecting elements 106A-106F, 108A-108C. But there may be a change in position or attitude between the base 102 and the payload 104. For the symmetric support configurations shown in FIGS. 1A and 1B, the only change is in the vertical direction between the two bodies 102, 104. The payload 104 may be rigidly supported and maintains position in the presence of environmental conditions, such as inertial loads. The location of an object in space is defined by three orthogonal coordinates or vectors, and the attitude of the object is defined by three orthogonal rotations with respect to the three vectors. In accordance with the present invention, if the components of an assembly (e.g., base, payload, and connecting structure such as bipods or monopods) are formed using an extremely precise fabrication method (e.g., micromachining), then the location and attitude of a payload relative to a base may be specified as precisely by fabricating connecting structure to calculated dimensions along their support DOF(s) (e.g., a precise length for a monopod, or a precise vertical and horizontal point of contact for a bipod). Degenerate Support If there are fewer than six DOFs constrained between the base 102 and the payload 104, there may be some trajectory, i.e., combination of Cartesian DOFs, of the payload 104 relative to the base 102 that is unconstrained. In this case, the support between the base 102 and the payload 104 may be called “degenerate,” and may occur when a connecting element 106 or 108 is missing or when certain connecting elements 106, 108 are parallel. Arbitrarily complex patterns of motion may be created or controlled by replacing one linear connecting element 106 or 108 with a linear actuator. Redundant Support If there are more than six DOFs constrained between the base 102 and payload 104, and the base 102 distorts or warps, there will be no solution of payload position and attitude that does not also warp the payload 104. This type of support may be called “redundant.” Monopods and Bipods FIG. 2A is a schematic side view of a monopod connecting element 106 shown in FIG. 1A. The monopod connecting element 106 in FIG. 2A constrains the base and payload assemblies 102, 104 with point contacts 200, 202 at two ends. FIG. 2B is a schematic side view of a bipod connecting element 108 shown in FIG. 1B. The bipod connecting element 108 in FIG. 2B constrains the base and payload assemblies 102, 104 with one or more (ideally) frictionless point contacts 204A, 204B at one end and two point contacts 206A, 206B at the other end. The DOFs restrained by the monopod and bipod connecting elements 106, 108 are indicated by arrows in FIGS. 2A and 2B. Six monopod connecting elements 106A-106F may constrain six DOFs between the base and payload assemblies 102, 104, as shown by the arrows in FIG. 1A. Also, three bipod connecting elements 108A-108C may constrain six different DOFs between the base and payload assemblies 102, 104, as shown by the arrows in FIG. 1B. Both types of joints (point-in-groove joint in FIG. 2A and circle-in-groove joint in FIG. 2B) may be used interchangeably. A preload may be used to maintain contact between the base 102, connecting element 106 or 108 and payload 104 in FIGS. 2A and 2B. Micromachining The base and payload assemblies 102, 104 and the connecting elements 106A-106F, 108A-108C in FIGS. 1A, 1B, 2A and 2B may be hereinafter referred to collectively as a “micromachined passive alignment assembly” or a “micromachined assembly.” Other micromachined alignment assemblies are described below. A micromachined assembly may be formed with methods described below with reference to FIGS. 31-33. In general, each component in the micromachined assembly in FIGS. 1A, 1B, 2A and 2B may be formed by first using a patterning process, such as lithography or photolithography, to form a desired pattern on a substrate wafer. The substrate wafer may comprise silicon or another suitable material, such as gallium arsenide or germanium. The lithography process may include applying a resist on a surface of a substrate wafer, aligning a mask with a desired pattern above the substrate wafer, exposing the resist to radiation, developing the resist, and hardbaking the resist. The radiation used for patterning the substrate wafer may include, by way of example, an ultraviolet light, an X-ray beam, or a beam of electrons. In one embodiment, the mask is be made of a mechanically rigid material that has a low coefficient of thermal expansion. For example, the mask may be made of quartz, borosilicates, metallic chrome, or iron oxide. Patterning may be accomplished using either negative or positive resists. In some applications, it is desirable to use positive resists with aspect ratios above unity. In some applications, a photolithographic process is used to form a desired pattern on the substrate wafer. In a photolithography process, a photoresist such as photo-sensitive film is used in the patterning process. After developing a pattern on the resist, one or more micromachining fabrication processes, such as Deep Reactive Ion Etching (DRIE), Wire Electric Discharge Machining (Wire EDM or WEDM), LIGA (X-Ray lithographic, galvanoformung, und abformtechnik) (X-Ray lithography, electrodeposition, and molding), or SCREAM (Single Crystal Reactive Etching and Metallization) may be used to etch the substrate wafer according to the masked pattern. In some applications, it is desirable to etch deep and straight sidewalls in the substrate wafer. In other applications, it is desirable to form a three-dimensional structure from the patterned wafer. After etching, the patterned wafer is cleansed. The photoresist and/or resist may be removed using a solvent such as acetone. If there are other fragile MEMs structures on the wafer, a plasma etch may also be used to clean the substrate wafer. After the fabricated components are cleansed, the components are assembled to form a desired micromachined passive alignment assembly. The fabrication processes described above may be used for making any part, element, patterned wafer, or component of the micromachined passive alignment assemblies described herein. FIGS. 31-33 provide additional details on micromachining in accordance with the present invention. Slip-Fit Joint A slip-fit caged joint is a slip-together pair of features which control at least one DOF in both directions (which may be called “tension” and “compression”), where fit tolerance is added to intrinsic feature accuracy. Since fit tolerances can be held to 1-3 microns, the tolerance may be the dominant error. A slip-fit caged joint still forms a relatively high accuracy connection. FIG. 3 is a three-dimensional view of one embodiment of a slip-fit joint assembly 300. The slip-fit joint assembly 300 comprises a payload assembly 302 and a base assembly 304. The payload assembly 302 has three protrusions (also called “tabs” or “male connectors”) with mating surfaces 306A-306C, 308A-308C and 310A-310C (not all mating surfaces are visible in FIG. 3). The base assembly 304 has counterpart grooves (also called “slots” or “female connectors”) with mating surfaces 312A-312C, 314A-314C, and 316A-316C (not all mating surfaces are visible in FIG. 3). The mating surfaces 306A-306C, 308A-308C, 310A-310C, 312A-312C, 314A-314C, and 316A-316C are configured to engage together. The mating surfaces 306A, 306C, 308A, 308C, 310A, 310C of the payload assembly 302 that are normal to the payload plane are configured to slide past the corresponding mating surfaces 312A, 312C, 314A, 314C, 316A, 316C of the base assembly 304. A protrusion such as protrusion 306 and a groove such as groove 312 control at least two DOFs 324, 326. A protrusion-groove pair maybe called a kinematic positioning joint. In one embodiment, there is a fit clearance between the mating surfaces 306A, 306C, 308A, 308C, 310A, 310C, 312A, 312C, 314A, 314C, 316A, 316C to assemble the slip-fit joint assembly 300 of FIG. 3. In some applications, it is desirable to have a fit clearance of about 1-3 microns. For example, the distance between the mating surfaces 312A, 312C is equal to the distance between the mating surfaces 306A, 306C plus a few microns. This fit clearance leads to positioning “slop” or “deadband” of a few microns in (1) the plane of the base assembly 304, which is defined by two DOFs 318 and 320, and (2) a few arcseconds in rotation about the normal of the base plane, which is shown as DOF 322. For rotational DOF 322 in FIG. 3 and other rotational DOFs described herein, such as DOFs 526, 528 in FIG. 5, the double arrows symbolize a rotation about the axis. Each double pair of mating surfaces 306A, 306C, 308A, 308C, 310A, 310C, 312A, 312C, 314A, 314C, 316A, 316C in FIG. 3 may contribute deadband (or free play) that is normal to their surfaces, which is shown as DOF 324. In one embodiment, a preload is applied to seat the mating surfaces 306B, 308B, 310B, 312B, 314B, 316B that are parallel to the payload and base planes without a deadband in DOF 326. Thus, the position of the payload assembly 302 normal to the base plane, illustrated as DOF 328, is specifically controlled, as well as the two orthogonal rotations shown as DOFs 330 and 332, whose axis lie in the base plane. The DOFs 328, 330, 332 may be referred to as piston, tip, and tilt. In embodiment of FIG. 3, the protrusions are square or rectangular in shape, while the female connectors are square or rectangular cavities. In other embodiments, other shapes may be used, such as cylindrical projections. With cylindrical projections, the restrained DOFs may be the same as described above, as specified by the base plane pairs 312A, 312C, 314A, 314C, 316A, 316C. FIG. 4 is a three-dimensional view of another embodiment of a slip-fit joint assembly 400. The slip-fit joint assembly 400 comprises a base assembly 404 and a payload assembly 402. The payload assembly 402 has protrusions 406, 408 and 410 with mating surfaces, while the base assembly 404 has counterpart recesses 412, 414, and 416 with mating surfaces. Like the slip-fit joint assembly 300 of FIG. 3, the protrusions 406, 408, 410 and recesses 412, 414, and 416 with mating surfaces can engage together like male and female connectors. In this embodiment, the male connectors 406, 408 and 410 are inverted T-like projections, while the female connectors 412, 414, and 416 are window openings in the base assembly 404. In FIG. 4, the bottom plane of the base 404 replaces surfaces 312B, 314B, 316B in FIG. 3, but the base 404 provides the same DOF constraints. The slip-fit joint assemblies 300 and 400 in FIGS. 3 and 4 may be fabricated with the same manufacturing procedures described above and below with reference to FIGS. 31-33. For example, the lithography process and the micromachining process may fabricate the desired mating surfaces 306A-306C, 308A-308C, 310A-310C, 312A-312C, 314A-314C, 316A-316C of the male and female connectors. In some applications, it is desirable to include a metallization process after the substrate wafer is cleaned. A metal is deposited via sputtering onto the male (tabs) and female connectors (slots). The metallization process increases robustness and reduces debris formation at the mating surfaces of the male and female connectors. In one embodiment, each element in an assembly is kinematically supported with respect to all other elements. If each connecting element (e.g., element 106 in FIG. 1A) is kinematically supported in addition to the base and payload, the DOFs controlled by the connecting elements are capable of more accurate positioning. Thus, there are no allowed trajectories of the connecting elements (degenerate support). An allowed trajectory (change of attitude) of a connecting element could disturb the desired DOF controlled by the connecting element. Also, there is no overconstraint (redundant support) that could warp the connecting elements. An overconstraint could change a controlled DOF position through applied strain. As a consequence of kinematic support, every structural element in an assembly can now be a “payload,” which could support one or more optical components to the same levels of accuracy previously described. In addition, an unlimited number of structural elements may be attached (to form a “daisy chain”) in this manner to a high level of accuracy. Each successive payload may be the base for the next payload in the chain. Another valid topology is to have an unlimited number of payloads attached to one set of connecting elements using the same DOFs at each connecting element (see “megastack” in FIG. 25). Other topologies may be possible. Pseudo-Kinematic Connecting Element, Flexure Systems, Ball Joints, Attachment Points FIG. 5 illustrates a three-dimensional view of one embodiment of a pseudo-kinematic connecting element flexure system and an attachment point 500. “Pseudo-kinematic” means that although there may be many DOFs connecting at least two bodies through a plurality of connecting elements, such as two micromachined passive aligmnent assemblies, in a practical attachment scheme, the DOFs can be tailored such that only six DOFs have relatively high stiffness, and substantially all other DOFs have relatively low stiffness. In some applications, it is desirable to have at least one DOF with low stiffness to be two to three orders of magnitude lower than a DOF with high stiffness. DOFs with different levels of stiffness may be accomplished using a flexure system, such as the flexure system 504 in FIG. 5, to relieve stiffness in unwanted DOFs. Hereinafter, “kinematic” may be used to refer to pseudo-kinematic attachments. In FIG. 5, the pseudo-kinematic connecting element flexure system and attachment point 500 comprises a body 502, a flexure system 504, and an attachment portion 506. The flexure system 504 couples the body 502 to the attachment portion 506. The attachment portion 506 and the flexure system 504 may be collectively referred to herein as a “ball joint,” a “ball joint flexure” or a “flexured ball joint” in a planar structure. A ball joint is a useful pseudo-kinematic structure that is relatively stiff in substantially all translations and relatively soft in substantially all rotations. One embodiment of the attachment portion 506 in FIG. 5 comprises a mounting tab 508 with mating surfaces (contact surfaces) 510A, 510B, 510D, 510E, which may provide high precision dimensional control to mating elements. The flexure system 504 comprises two flexure elements 512, 514 that form a bipod-like structure. Each flexure element 512, 514 is very stiff in at least an axial direction. Thus, each flexure element 512, 514 provides a very stiff connection between the attachment portion 506 and the body 502 in DOFs 516 and 518, as shown in FIG. 5. Depending on the cross-sectional properties of the flexure system, the connecting elements may have compliant (or “soft”) rotations become stiff and stiff translations become soft. The cross-sectional properties of the flexure elements 512, 514 include blade depth 520, blade length 522, and blade thickness 532. If the blade depth 520 of the flexure elements 512, 514 is significantly smaller (e.g., less than {fraction (1/10)}) than the blade length 522, the attachment of the body 502 to the attachment portion 506 by the flexure elements 512, 514 may have two stiff DOFs 516, 518 (i.e., forming a bipod), and other relatively softer DOFs 524, 526, 528, 530. In other applications, if the flexure elements 512 and 514 have a blade depth 520 that is significant (e.g., greater than about {fraction (1/10)} of the blade length 522), then DOF 524 has significant stiffness, and the attachment has the properties of a ball joint. The rotational DOFs 526, 528 may become stiffer compared to DOF 530, which is primarily controlled by the flexure blade width 532. In one embodiment, DOFs 526, 528 are soft and DOF 530 is very soft compared to DOFs 516, 518. Depending on the exact magnitude and the sensitivity of a particular design, the soft DOFs 526, 528 may not cause any problems. The stiffness of DOFs is highly dependent on the exact cross-sectional properties (blade depth 520, length 522, and thickness 532) of the flexure elements 512, 514. It would be relatively easy to make the “soft” rotational DOFs 526, 528 stiffer and make the “stiff” translation 524 softer by changing the cross-sectional properties. As long as the blade length 522 is much greater than the blade depth 520 and the blade thickness 532, e.g., 10 to 1 ratio (other ratios may be used), the “very stiff” translations 516 and 518 and the “very soft” rotation 530 will remain unchanged for this configuration. In one configuration, it is desirable to have a ball joint at both ends of the body 502 to form a monopod connecting element (not shown). This configuration would create an appropriate set of stiff DOFs to make the monopod connecting element act like a single DOF constraint between two bodies. Pseudo-Kinematic Bipod Connecting Element In another configuration, it is desirable to have three attachment portions, similar to the attachment portion 506, coupled to the body 502 to form a pseudo-kinematic bipod connecting element, as shown in FIG. 6. FIG. 6 is a three-dimensional view of one embodiment of a pseudo-kinematic bipod (i.e., two-DOF support) connecting element 600. The pseudo-kinematic bipod connecting element 600 comprises attachment points 602, 604, 606 and a body 608. The two attachment points 602 and 604 of the connecting element 600 may connect to a base assembly (not shown). The attachment point 606 may connect to a (nominal) payload assembly (not shown). Two of the attachment points 602 and 606 are coupled to the bipod body 608 via ball joint flexures, as described above with reference to FIG. 5. The ball joint at attachment point 602 provides three DOFs 610, 612, 614 of connectivity to the body 608. The ball joint at attachment point 606 provides three DOFs 616, 618, 620 of connectivity to the body 608. The attachment point 604 connects to the bipod body 608 via a single flexure 622 that provides two DOFs of connectivity 624 and 626. In one embodiment, three bipod connecting elements, such as the element 600 in FIG. 6, are kinematic in their attachments to a base and a payload. The three bipod connecting elements also form a kinematic attachment between a base and a payload. In FIG. 6, the pseudo-kinematic bipod connecting element 600 “borrows” several DOFs 610, 612, 614, 616, 624, 626 from the base assembly and the payload assembly to control the position and attitude of the bipod connecting element 600. This set of DOFs 610, 612, 614, 616, 624, 626 forms a 3-2-1 support structure (3 DOFs at one point, two DOFs at another, one DOF at a third) that is kinematic or pseudo-kinematic. Thus, the pseudo-kinematic bipod connecting element 600 could itself be an optical bench. The remaining DOFs 618 and 620 are used by the pseudo-kinematic bipod connecting element 600 to control the payload assembly. The DOFs 610, 612, 614, 616, 618, 620, 624 and 626 may depend on one or more assumptions described above. For example, it may be assumed that the payload assembly is fully constrained by other pseudo-kinematic bipod connecting elements 600. Otherwise, the “borrowed” DOF 616 may not be constrained. As another example, at each attachment point 602, 604, 606 connected to a base or payload, all six DOFs with the attached body may be constrained by an adhesive or a preload (discussed below) to seat the mating surfaces without a deadband. The flexure structures may then select a subset of these DOFs to connect (i.e., be stiff in) to the body 608 to create the kinematic condition. The structures described herein may have high stiffness in certain DOFs and much lower stiffness in all other DOFs. Some DOFs may vary in a common fashion with changes in flexure system dimensions, possibly requiring that a design decision may be made between either (1) allowing extra stiff DOFs, where an attachment may no longer be pseudo-kinematic, or (2) allowing a desired stiff DOF to be soft, which leaves the assembly with a relatively low frequency vibration mode and any desired positional accuracy in that direction may be compromised. Each of the two choices may be a viable design. An extra stiff DOF means a redundant support, which may be undesirable for an optical bench connected to a poorly-controlled external structure, but may be acceptable for certain size scales or sets of assumptions. Low frequency vibration modes may be a problem, but if the low frequency is in the kilohertz range while the device operates in approximately the 100-Hertz range, there will not be a detrimental dynamic interaction. The connecting elements 500 and 600 in FIGS. 5 and 6 may be fabricated with micromachining manufacturing methods described herein. For example, lithography and micromachining can fabricate the connecting elements 500 and 600 to the sub-micron level. To translate these highly accurate planar processes to highly accurate three-dimensional positioning accuracy requires the same DOF control used for kinematic attachment. In other words, the stiff constrained directions used to form a kinematic attachment (e.g., the directions constrained between a base and a payload by three bipod connecting elements) can also have a precisely-determined dimension associated with each of them, thereby uniquely and precisely specifying the position (translations) and attitude (rotations) between two bodies (e.g., a base and a payload). This precisely-determined dimension is shown in detail below in FIG. 7 for one bipod element. FIG. 7 illustrates an example of the pseudo-kinematic bipod connecting element 600 (alignment features on a planar object) in FIG. 6 attached to a base assembly 702 and a payload assembly 704. The attachment points 602, 604 and 606 engage into the base assembly 702 and the payload assembly 704 at the mating surfaces 706A, 706B, 706D, 706E, 708A, 708B, 708D, 708E and 710A, 710B, 710D, 710E, respectively. The bipod connecting element 600 has two constrained and precisely specified DOFs at the payload 704 (DOFs 618 and 620 in FIG. 6). One alignment feature in FIG. 7 may be a precise separation distance 712 between the base assembly 702 and the payload assembly 704, which is defined by a midpoint 714 of a line formed by mating surfaces 706A and 706E of attachment point 602 and another midpoint 716 of a line formed by mating surfaces 710A and 710E of attachment point 606. This precise separation distance 712 precisely specifies the location of the payload assembly 704 relative to the base assembly 702 in the vertical direction (DOF 620 from FIG. 6) at the point of attachment between the connecting structure (600 from FIG. 6) and the payload assembly 704. Another alignment feature may be the lateral (horizontal) distance 718 between the mating surfaces 706B and 710B, which may be zero, as shown in FIG. 7. In one configuration, the mating surfaces 706B, 710B may be collinear. Thus, the mating surface 706B forms a straight line with the mating surface 710B. Each vertical mating surface 706B, 710B may set a lateral position reference between the attachment points 602, 606. This precisely specifies the location of the payload assembly 704 relative to the base assembly 702 in the horizontal direction (DOF 618 in FIG. 6) at the point of attachment between the connecting structure (600 in FIG. 6) and the payload assembly 704. Another alignment feature may be a pair of collinear line segments (that are also mating surfaces) 708A, 708E that interface the base side 702, are remote from point 714 and are collinear with 706A, 706E. The fine segments 708A, 708E constrain the rotation of the planar object 600 about a normal to the plane of FIG. 7. Note that attachment point 604 could also interface to the payload side 704, and the constraint would be identical. This rotational constraint may completely restrain the connecting element 600 in the desired DOFs. Otherwise, rotation in-plane of FIG. 7 would nullify the proper function of the vertical and horizontal position reference features described above. In summary, the base and payload planes in FIG. 7 are parallel and separated by a specific distance 712. In this example, the sets of collinear line segments 706A, 706E, 710A, 710E that define the separation distance are also parallel, and the lateral position reference 718 is zero (collinear line segments 706B, 710B) between the two connected objects 702, 704. Thus, the connecting element 600 in FIG. 6 not only supports a payload 704 relative to a base 702 in 2 DOFs 618, 620, but also precisely locates the payload 704 relative to a base 702 in these same DOFs. Hence, three of these structures 600 would not only provide kinematic attachment between a payload and a base, but also completely and precisely specify the location and orientation of the payload relative to the base. The method of engaging attachment points 602, 604, 606 may be the same for the attachment portion 506 of the pseudo-kinematic connecting element 500 shown in FIG. 5 and described above. The above described connecting structure also applies for the more general case of non-parallel base and payload plates. Design/Fabrication Considerations Since the alignment features of the connecting element 600 discussed above are all coplanar lines, a mask with the desired pattern can be made for the patterning process (e.g., lithography). The patterning process can locate alignment features with high precision in a substrate wafer plane immediately adjacent to the mask. In some applications, it may be important to consider two design and fabrication points for connecting elements 500 (FIG. 5) and 600 (FIGS. 6 and 7). First, the mask sides or regions of a substrate wafer intended to form mating features should be substantially in contact with the mask sides of other elements for highest precision. For example, for highest precision, the mask sides in FIG. 7 should be the upper surface of the base assembly 702 and the lower surface of the payload assembly 704. Second, a micromachining process may either etch (cut) through the substrate wafer in a perfectly perpendicular manner or with a draft (e.g., inward draft). Etching the substrate in a perfectly perpendicular manner is the ideal case. If drafting occurs, it is recommended to have an inward draft with acute angles measured from the mask plane to the etched sides of the substrate wafer. It may be important to ensure contact at the masked side of the substrate wafer. In one embodiment, the amount of draft should be as small as practical, such as just enough draft to ensure there is nothing beyond a perpendicular cut (outward draft; obtuse angle) within the error of the micromachining process. For example, in one configuration, the draft is half a degree. As a result of inward drafts, some of the ideal line contacts, shown in FIG. 7 as mating surfaces 706B, 706D, 708B, 708D, 710B, and 710D, may be reduced to point contacts with very shallow angles. The mating surfaces 706A-E, 708A-E, and 710A-E for the base assembly 702, the payload assembly 704 and the connecting element 600 may all experience drafts. Thus, the mating surfaces 706B and 710B (which define lateral position reference line segments 718) may actually be contact points on the mask sides of the base assembly 704 and the payload assembly 706. Inward drafting may be acceptable because the two planes of two mating surfaces, which coincide at a point contact, form a very acute angle. Thus, if a load is applied, a substantial contact patch may be formed, and hence result in reasonable contact stresses. Internal Load and Flexure Assembly To obtain maximum accuracy, the mating features described herein may be preloaded together with an externally-applied load (e.g., to seat mating features during a bonding operation) or an intemally-reacted set of loads. In the latter case, the preload may be permanently applied and bonding may not be necessary. Internally reacted loads may be created by deflecting a flexure assembly (see FIG. 8) that is micromachined into one or more of the connected planar structures. FIG. 8 is a side view of one embodiment of an internal flexure assembly 800 (also referred to herein as an “internal preloader” or “preload”). The internal flexure assembly 800 comprises a set of double-parallel-motion flexures 802A-802B, 804A-802B (double-parallel-motion set) with outer ends connected to a wafer 806. In one embodiment, the internal flexure assembly 800 may further comprise a preloader stage 808 connected to the inner ends of the flexures 802A-802B and 804A-802B. The stage 808 constitutes a linear motion control device and hence may be called a “stage.” In one embodiment, it is desirable to have a hole 810 on at least one side of the preloader stage 808 for inserting a preloader pin (see FIG. 10). In some applications, it is desirable to use the internal flexure assembly 800 to provide internal preloading in a substrate wafer, thereby seating mating surfaces together without a deadband. Internal preloading occurs when the flexures 802A-802B, 804A-804B are deflected by the action of inserting a preloader pin, or more generally a mating feature of another planar structure. Each flexure 802A-802B and 804A-804B constrains DOFs such that the preloader stage 808 is supported very stiffly in five DOFs, but is soft in the one remaining DOF 812 (i.e., forming a spring). This soft DOF 812 is in the direction where the preload is applied. An applied deflection 816 results from a force 814 applied at the preloader stage 808. The force 818 is equal to and opposite to a resultant force 814 (internally reacted force) applied by the preloader stage 808 to the connected wafer 806 in the vertical direction in FIG. 8. The force 818 is the preload force used to positively seat a mating element against reference features (see FIGS. 9 and 11). In one embodiment, a relatively large deflection 816 is required to generate a preload 818. The internal flexure assembly 800 in the planar structure of FIG. 8 may be micromachined with high accuracy. Thus, the flexures 802A-802B, 804A-802B may have highly-accurate stiffnesses. Thus, deflections 816 of the flexures 802A-802B, 804A-802B should generate very accurate, repeatable and/or predictable preloads from device to device. By internally reacting these accurately-defined preloads, negligible distortion may occur in mated structures. A maximum deflection capability defined by a “deflection stop” 820 may be implemented to limit the motion of the preloader stage 808. If the applied deflection 816 is close to the deflection stop 820, then motions of an assembled structure (because of further elastic deflection of the preloader stage 808 due to inertial or external loads on the assembly) will be limited to the difference in height 822 between the applied deflection 816 and the maximum deflection 820. Tab and Slot In some configurations, it is desirable to attach micromachined passive aligmnent assemblies using male and female connectors, such as by way of example, a tab and slot attachment scheme. FIG. 9 illustrates two examples of preloading using a tab and slot attachment scheme with the internal flexure assembly 800 of FIG. 8. The tab 902 may be used as an attachment point for a connecting element, or a male or female connector for a base or payload assembly. The tab 902 has two substantially vertical mating surfaces 904 and 906, and two horizontal mating surfaces 908 and 910. In FIG. 9, a connecting object 912 (such as a horizontal wafer) has an opening or slot for inserting the tab 902 (FIG. 9 is a section view along the long axis of the slot, normal to the plane of object 912, and in the plane of the tab 902). The connecting object 912 may have mating surfaces such as surfaces 914, 916 that serve as counterparts to the mating surfaces 904, 906 of the tab 902. When the tab 902 is inserted into the slot, the vertical mating surfaces 904, 906 (horizontal constraint features) of the tab 902 rest against the ends 914, 916 of the slot in the connecting object 912, and the horizontal mating surfaces 908, 910 (vertical constraint features) of tab 902 rest against the lower surface of object 912. In one example of preloading, if a lateral position/motion constraint is desired, one substantially vertical mating surface 904 of the tab 902 is made to bear against one end 914 of the slot. The other end 916 of the slot comprises a stage for a flexure preloader 934. The substantially vertical mating surface 906 of the tab 902 may be formed at an angle 918 (angle relief) to enable initial vertical engagement against the end 916 of the slot. When the tab 902 is fully seated in the vertical direction in the slot of the connecting object 912, the preloader stage 934 is displaced laterally (to the left, as indicated by an arrow 920) a sufficient amount to generate a desired load. 922 (to the right) against the mating surface 906 of the tab 902. Another example of preloading in FIG. 9 involves the internal flexure assembly 924 (also called a flexure preloader) in the tab 902 as a vertical position/motion constraint. The internal flexure assembly 924 is micromachined into the tab 902 with a soft DOF 926 of the preloader stage 928 in the vertical direction. When the tab 902 is approximately seated vertically (i.e. surfaces 908 and 910 in approximate contact with connecting object 912), there is a hole 930 whose top edge is the preloader stage 928 and whose bottom edge and sides are in the tab 902. In one embodiment, the bottom edge of the hole 930 is a horizontal surface of a part 932 of the connecting object 912 (wafer). The shape of the hole 930 may be rectangular, circular, polygon or other shape, depending on the design of the micromachined passive alignment assembly. A separate structure called a preloader pin (see FIG. 10) may be inserted in the hole 930 in FIG. 9 to generate a vertical preload force pair 936, 938 (via upward displacement of the stage 928). The force 936 acts on the tab 902 and force 938 acts on the part 932 of connecting object 912 that forms the bottom of hole 930. These forces 936, 938 are then reacted across the horizontal mating surfaces 908, 910 and the lower surface of object 912 by force pairs 940, 942 and 944, 946, which forces these surfaces into intimate contact and creates a more precise (i.e. deadband free) vertical position constraint. At this point, in the absence of any flexured “ball joint” type structure attached to tab element 902, a vertical constraint on the paired surfaces 908 and 910 also creates a (possibly redundant) rotational constraint out of the plane of FIG. 9. This may be acceptable (see sections “Redundant Elements for Additional Stiffness/Planarity Enforcement” and “Optical Element Support Structure”). FIG. 10 is a three-dimensional view of one embodiment of a preloader pin 1000. The preloader pin 1000 may be fabricated using patterning and micromachining processes discussed herein. The preloader pin 1000 may be made of silicon, plastic or some other suitable substance. The cross-section of the preloader pin 1000 may be a rectangle, a circle, a square, a polygon or some other suitable shape. In one embodiment, the end of the preloader pin 1000 has a substantially square cross-section with four sides that are preferably about 500 microns in length. The shape of the right cross-section end of the preloader pin 1000 is configurable and may depend on the shape of the hole 930 in FIG. 9, such that when the preloader pin 1000 is fully inserted in the hole 930, the preloader stage 928 is deflected vertically a desired amount. Gently tapering the preloader pin 1000 in the vertical direction 1002 allows a low-force initial insertion and engagement. In some applications, the preloader pin 1000 is maintained in the hole 930 (FIG. 9) by friction. The frictional holding should be good to several hundred times gravitational acceleration. In other applications, it may be desirable to dispense an adhesive (e.g., spot of glue) on the preloader pin 1000 to restrain the pin 1000 in the hole 930. In FIG. 10, the preloader pin 1000 may comprise a stop flange 1004 to provide a positive stop location after inserting the preloader pin 1000 in the direction of insertion 1008. The preloader pin 1000 may also comprises an edge relief 1006 to allow for any sharp corners of the mating surfaces in the preloader stage 928 (FIG. 9) or hole 930. In FIG. 9, the flexure preloader 934 and the other flexure preloader (internal flexure assembly 924) each form an intemally-reacted set of loads. In the first example described above, the force reaction points are the two substantially vertical mating surfaces 904 and 906 of the tab 902 and the two ends 914 and 916 of the slot, where one end 916 comprises a stage of a flexure preloader 934. The preload 920 causes simple compressive stress locally in the tab 902, and a somewhat more complex yet still local tensile stress pattern around the slot. By virtue of the softness of the preloader 934, the forces and hence stresses can be made very small in absolute value. Since strain is proportional to stress, and overall distortion is proportional to strain times a distance, small localized strains create negligible overall distortions. FIG. 11 illustrates an assembly 1100 where two internal flexure assemblies 1102 and 1104 are used to maintain the 2-DOF, in-plane position of a tab 1106, i.e., maintain contact at mating surfaces of a slot. The tab 1106 in FIG. 11 may represent a top view of the tab 902 in FIG. 9, and a planar object 1100 in FIG. 11 may represent a top view of the connecting object 912 in FIG. 9. As in FIG. 9, the tab 1106 in FIG. 11 fits in a slot in the object 1100. Thus, an internal flexure assembly 1102 in FIG. 11 may represent the flexure preloader 934 described above in the first preloading example of FIG. 9. The internal flexure assembly 1102 in FIG. 11 controls the vertical position of the tab 1106 in FIG. 11 by preloading surface 1118 of tab 1106 against surface 1120 of planar object 1100. These surfaces are analogous to 904 and 914, respectively, in FIG. 9. The other internal flexure assembly 1104 in FIG. 11 controls the horizontal position of the tab 1106. The internal flexure assembly 1104 has a hole 1108 configure to receive a preloader pin 1110. FIG. 11 shows an end view of the preloader pin 1000 in FIG. 10. When a preloader pin 1110 is inserted into the hole 1108, the pin 1110 causes a horizontal deflection 1112 (to the right) of a preloader stage 1114, which causes a horizontal force 1116 (substantially equal and opposite to the deflection 1112) applied by the preloader stage 1114 on the pin 1110 and the tab 1106. This forces surface 1122 of tab 1106 into intimate contact with surface 1124 of planar object 1100. Partially-Degenerate, Partially-Redundant, Pseudo-Kinematic Designs The level of stiffness or softness of a particular DOF depends on design factors such as plate stiffness of an attached structure, a desired precision of position, thermal and dynamic environment, etc. An alignment assembly may be designed to be partially-degenerate, partially-redundant or a pseudo-kinematic design with substantially six stiff DOFs. To construct a partially-degenerate support, design analysis determines resonant modeshapes and frequencies and verifies that the modeshapes and frequencies do not negatively impact the design. For a partially redundant support, an appropriate analysis involves application of dynamic and thermal environments to verify that distortions caused by the dynamic and thermal environments are less than the desired precision. For many applications of these micromachined pseudo-kinematic structures, there may be two things in common: (1) all component structures may be made of silicon and (2) the payload and the base may be parallel. Where either of these conditions occur, it is possible to greatly relax the constraints of kinematicity. If a structure is all silicon, a highly redundant support system can be used. If redundant DOFs are properly chosen, the payload may only experience warping in the presence of high thermal gradients, which is unlikely given the high conductivity of silicon and the small dimensions involved. If a symmetric support is used and the base and payload are parallel, bulk temperature changes would cause only a piston shift (no lateral, tip, tilt, or roll shift). The design and fabrication combination of solid modeling software and lithographic micromachining allows the construction of multi-part assemblies where the fit-up on assembly may be virtually perfect, even with complex geometries. The construction of multi-part assemblies where the fit-up on assembly may be virtually perfect may obviate the need for kinematic attachment in many cases. In the macroscopic world, much of the need for kinematic support is due to imperfections of the mounting surfaces. An added benefit of a redundant support is greater stiffness of each of the component parts of the assembly. Extended line contacts effectively restrain out-of-plane deformations in a wafer. Fiber Termination Array Assembly FIG. 12A is a three-dimensional enlarged view of one embodiment of a fiber termination array assembly 1200 (also called a fiber alignment device). FIG. 12B is a three-dimensional assembled view of the fiber termination array assembly 1200 in FIG. 12A. The fiber termination array assembly 1200 may be formed by one or more processes described in co-assigned U.S. patent application Ser. No. 09/855,305, entitled “ANGLED FIBER TERMINATION AND METHODS OF MAKING THE SAME” (Attorney Docket No. M-11564 US), which is hereby incorporated by reference in its entirety. The fiber termination array assembly 1200 comprises a fiber locator plate 1202, a fiber termination plate 1204 and three connecting elements 1206A-1206C. The fiber termination plate 1204 has a polished optical surface 1216, holes 1220 configured to support/align optical fiber ends and kinematic positioning slots 1208, 1214 (with mating surfaces). The slots 1208, 1214 are configured to receive a tab (with mating surfaces), such as tab 1210, of the connecting elements 1206A-1206C. The fiber locator plate 1202 also has holes 1218 configured to support/align optical fibers and slots, such as slot 1212, configured to receive a tab of the connecting elements 1206A-1206C. In one configuration, the connecting element protrusions 1222 form extended line contacts that effectively restrain out-of-plane deformations in the fiber termination plate 1204 and/or the fiber locator plate 1202. The three connecting elements 1206A-1206C constrain the fiber termination plate 1204 to the fiber locator plate 1206 with about six DOFs. Each connecting element 1206 may control two DOFs of position and may have four to five DOFs of stiffness. Although one connecting element 1206A may be redundant in a stiffness DOF in view of the other connecting elements 1206B, 1206C, each connecting element controls two DOFs of position and may precisely position the fiber locator plate 1202 with respect to the fiber termination plate 1204. In some applications, it may be desirable to connect the fiber termination plate 1204 and the fiber locator plate 1202 with more than six stiff DOFs. For example, more than six stiff DOFs are used to reinforce flatness, add stiffness, and prevent sagging under gravity or vibration for the fiber termination plate 1204 and the fiber locator plate 1202. In one embodiment, the assembly 1200 was analyzed for polishing pressure on an optical face on the fiber termination plate 1204 and found to have deformations on the nanometer level with typical polishing pressures. As shown in FIGS. 12A and 12B, two objects, such as two planar silicon wafers, may be positioned precisely relative to each other in six DOFs (tip, tilt, piston, roll, and two in-plane DOFs (lateral to separation direction)) to lithographic levels of precision or exactness. The two objects may be positioned by using planar connecting structures, each with mating reference features to control one or more DOFs between the two objects for a total of six DOFs. The objects and connecting structures may all be fabricated using lithographic micromachining techniques, or their equivalents in precision. The two objects to be aligned may contain arrays of optical components, which are already precisely positioned within the plane such that the two arrays would be precisely positioned relative to each other. If the above positioning concept has no internal preloading, some gaps are allowed between mating features to ensure assembly. These gaps may contribute to the overall error in the positions of objects in the assembly. If the above positioning concept has internal preloading, internally reacted loads ensure contact between mating surfaces, remove any gaps and allow a very high assembly precision. Redundant Elements for Additional Stiffness/Planarity Enforcement Large pseudo-kinematically supported planar arrays may be designed with extra bending stiffness to resist inertial loads. To implement extra bending stiffness, redundantly-attached ribs may be added to a main wafer plane. The redundantly attached ribs may be designed to actually enforce the flatness of the main wafer. This enforcement may be done to lithographic precision. FIG. 13 is a side view of two embodiments of redundant connecting elements 1302 (also called ribs) and 1304 and a plate 1306 (also called wafer). The wafer 1306 may be used as an optical bench to support optical elements 1308, 1309 such as fibers, lenses or mirrors. In one embodiment, a wafer 1306 (e.g., a base assembly or a payload assembly) is supported with more than six stiff DOFs to enforce flatness (i.e., planar surface control), add extra stiffness, resist inertial loads (e.g., sagging or bending under gravity or vibration of the wafer 1306), and/or resist extemally-applied loads from the environment. Thus, less strains or distortions are communicated to the optical elements 1308 and their positions remain more precise. The connecting elements 1302 and 1304 may be designed with redundant tabs 1310A-1310C, 1314A-1314C (also called attachment points). The connecting elements 1302 and 1304 may be fabricated with high precision using the patterning and micromachining processes discussed above. In one embodiment, the connecting element 1302 has tabs 1310A-1310C that may engage into slots 1312A-1312C of the wafer 1306. The attachment mechanism of the tabs 1310A- 1310C and slots 1312A-1312C may encompass external preloading and gluing of the tab into the slot. FIG. 13 shows a tab 1320 of a connecting element, such as connecting element 1302, that is flush with the top surface of the wafer 1306. In another embodiment, the connecting element 1304 has tabs 1314A-1314C with internal flexure assemblies 1316 (with preloaders), which are micromachined in the tabs 1314A-1314C. The attachment mechanism of the tabs 1314A-1314C and slots 1312A-1312C may follow the second example described above with reference to FIG. 9. FIG. 13 shows a tab 1318 of a connecting element, such as connecting element 1304, protruding from a top surface of the wafer 1306. Each tab 1318 may use a connecting pin (not shown). FIG. 14 is a three-dimensional view of the two connecting elements 1302 and 1304 and the plate 1306 of FIG. 13. FIG. 14 shows protruding, attached tabs 1318A, 1318B and attached tabs 1320 that are flush with the top surface of the wafer 1306. The tabs 1318A, 1318B, 1320 are part of connecting elements underneath the plate 1306. Each connecting element 1302, 1304 may have any number of tabs, such as six tabs, as shown in FIG. 14. Pseudo-Kinematic vs. Partially-Degenerate Support FIGS. 15, 16 and 17 illustrate the difference between a pseudo-kinematic support system and partially-degenerate support systems. FIG. 15 is a three-dimensional view of one embodiment of a pseudo-kinematic support system 1500. The pseudo-kinematic support system 1500 in FIG. 15 comprises a box-like structure 1510 and three pseudo-kinematic, planar, bipod connecting elements 1502A-1502C (referred to as “bipod connecting elements”). Each bipod connecting element 1502 may have two stiff or very stiff DOFs. For example, bipod connecting element 1502A has two stiff DOFs 1504A-1504B. Bipod connecting element 1502B has two stiff DOFs 1506A-1506B. Bipod connecting element 1502C has two stiff DOFs 1508A-1508B. Thus, the bipod connecting elements 1502A-1502C may constitute a complete support (six stiff DOFs) for the box-like structure 1510 (e.g., base assembly or payload assembly). The remaining DOFs (not shown in FIG. 15) may be soft. To determine whether or not a set of support DOFs is kinematic, redundant, or degenerate, the directions and points of application of each set of support DOFs should be considered. Kinematic may also be referred to as “determinate” or “statistically determinate.” Redundant may also be referred to as “indeterminate” or “statistically indeterminate.” In some applications, it is desirable to have a degenerate support system, for example, when building a motion control stage. A degenerate support system constrains base and payload assemblies with less than six DOFs. As a result, there may be some trajectory (i.e. combination of Cartesian DOFs) of the payload assembly relative to the base assembly that is unconstrained. A degenerate support system may occur when a connecting element is missing or when certain connecting elements are parallel. Although a degenerate support and a partially-degenerate support constrain base and payload assemblies with less than six DOFs, a degenerate support will move in some trajectory direction that is unconstrained while a partially-degenerate support will move in some trajectory direction that is resisted by soft DOF(s) from the pseudo-kinematic connecting elements. The trajectory direction of the degenerate support would have no restoring force and zero resonant frequency. Meanwhile, the trajectory direction of the partially-degenerate support would have relatively little restoring force, and a relatively low resonant frequency. FIG. 16 is a three-dimensional view of one embodiment of a partially-degenerate support system 1600. The partially-degenerate support system 1600 in FIG. 16 comprises a box-like structure 1612, two pseudo-kinematic, planar, bipod connecting elements 1602A-1602B (referred to as “bipod connecting elements”) and one pseudo-kinematic, planar, monopod connecting element 1604 (referred to as “monopod connecting element”). While the two bipod connecting elements 1602A-1602B each have two stiff DOFs 1606A-1606B, 1608A-1608B, the monopod connecting element 1604 has one stiff DOF 1610. Because the bipod connecting elements 1602A-1602B and the monopod connecting element 1604 are pseudo-kinematic, the remaining DOFs (not shown) may be soft. Since the partially-degenerate support system 1600 restrains the structure 1612 with five stiff DOFs 1606A-1606B, 1608A-1608B, and 1610, there may be some trajectory direction 1614 for the structure 1612. Motion in this trajectory (motion direction) 1614 is resisted by out-of-plane bending of the bipod connecting elements 1602A-1602B and in-plane or out-of-plane bending of the monopod connecting element 1604, which are all fairly soft DOFs. Motion along trajectory direction 1614 would therefore have little restoring force, and thus would have a low resonant frequency. The compliance in trajectory direction 1614 would also mean any precise positioning features designed to control motion along the trajectory direction 1614 may have degraded performance. FIG. 17 is a three-dimensional view of another embodiment of a partially-degenerate support system 1700. The partially-degenerate support system 1700 comprises three connecting plates 1710A-1710C and three pseudo-kinematic, planar, bipod connecting elements 1702A-1702C (referred to as “bipod connecting elements 1702A-1702C”). Each bipod connecting element 1702A-1702C has two stiff or very stiff DOFs. For example, bipod connecting element 1702A has two stiff DOFs 1704A-1704B. Bipod connecting element 1702B has two stiff DOF 1706A-1706B. Bipod connecting element 1702C has two stiff DOF 1708A-1708B. In one embodiment, where the three plates 1710A-1710C are rigidly attached to each other, the system 1700 has a total of six stiff DOFs 1704A-1704B, 1706A-1706B, 1708A-1708B. The remaining DOFs (not shown) may be soft. Because the attachment points of the three bipod connecting elements 1702A-1702C are collinear, one bipod connecting element 1702A may be ineffective. Thus, the three connecting plates 1710A-1710C with three bipod connecting elements 1702-1702C may have only four stiff DOFs, including two trajectory directions 1712 and 1714 with very low stiffness. Strain Isolation As explained above, one or more internal flexure assemblies may seat mating surfaces together without a deadband. One or more internal flexure assemblies may also be used to resist load-induced or temperature-induced strains/distortions in a base assembly from transferring to a payload assembly, or vice versa. At most, there may be a position shift and/or an attitude shift of the base assembly with respect to a payload assembly, or vice versa. FIG. 18 is a three-dimensional view of one embodiment of a strain isolation flexure assembly 1800. The strain isolation flexure assembly 1800 in FIG. 18 comprises one or more payload assemblies 1810 and a base assembly 1808 with micromachined features, such as three micromachined outer internal flexure assemblies 1802A-1802C (i.e., “strain-isolation mounting flexures” or “mounting flexures”), a plurality of holes 1814 and a set of inner internal flexure assemblies 1816A-1816C around each hole 1814. The outer internal flexure assemblies 1802A-1802C in FIG. 18 may be oriented 120 degrees apart, as shown in FIG. 18, or oriented at any arbitrary angle or distance from each other, preferably with the lines-of-action 1804A-1804C (i.e., soft direction of the flexure system) meeting at some common point, such as point 1806. In some applications, it may be desirable to have less than three or more than three outer internal flexure assemblies in the strain isolation flexure assembly 1800. Each outer internal flexure assembly 1802 controls two DOFs, such as DOF 1818A (vertical, out-of-plane) and DOF 1818B (in-plane). FIG. 18 illustrates three lines of action 1804A-1804C that intersect at a centroid 1806. The three lines of action 1804A-1804C represent degrees of flexibility or soft DOFs provided by the outer internal flexure assemblies 1802A-1802C. Any distortion or strain in a foundation (not shown), to which the base assembly 1808 is attached via flexure assemblies 1802A-1802C, can be accommodated by motion along the lines of action, thereby generating only minute forces in the base assembly 1808 from restoring forces in the flexure systems 1802A-1802C. Thus, the outer internal flexure assemblies 1802A-1802C may prevent load-induced strains/distortions in a foundation from communicating to the base assembly 1808, and hence maintain the relative location of one or more payload assemblies 1810, which are attached to the base assembly 1808. Thus, the flexure assemblies 1802-180C may be called “strain isolation mounting flexures.” At most, there may be a position shift and/or an attitude shift of the base assembly 1808 with respect to the foundation, or vice versa. The outer internal flexure assemblies 1802A-1802C maintain a pseudo-kinematic state between the base assembly 1808 and the foundation. The pseudo-kinematic state may be particularly important when the base assembly 1808 is used as an optical bench to support payload assemblies 1810. Maintaining a pseudo-kinematic state between the base assembly 1808 and the foundation reduces the amount of strains/distortions in the base assembly 1808, hence maintaining the relative positions of the payload assemblies 1810. Thermal Compensation FIG. 19 illustrates a part of the base assembly 1808 in FIG. 18, a payload assembly 1810, an optical element 1812 supported by the payload assembly 1810, an outer internal flexure assembly 1802, a hole 1814 and a set of inner internal flexure assemblies 1816A-1816C around the hole 1814. One or more optical elements 1812 may be inserted in each hole 1814. The payload assembly 1810 (e.g., silicon optical bench) in FIG. 19 is directly connected to the base assembly 1808, and the connection points are flexured to attain a pseudo-kinematic state. In other embodiments, there may be more than three or less than three inner internal flexure assemblies 1816A-1 816C. The inner internal flexure assemblies 1816A-1816C may be oriented 120 degrees apart or oriented at any arbitrary angle or distance or angle from each other, preferably with the lines-of-action 1908A-1908C meeting at a common point (e.g.1910). For example, the inner internal flexure assemblies 1816A-1816C in FIG. 19 are oriented 90 degrees apart. The inner internal flexure assemblies 1816A-1816C in FIG. 19 may be referred to as thermal compensation flexures, which may be used to maintain hot die passive alignment. The inner internal flexure assemblies 1816A-1816C together may be called a thermal compensation flexure assembly. FIG. 19 illustrates three lines of action 1908A-1908C that intersect at a centroid 1910. The three lines of action 1908A-1908C represent degrees of flexibility or soft DOFs provided by the inner internal flexure assemblies 1816A-1816C. An optical element 1812, such as a diode, will expand as the element 1812 rises in temperature (generates or absorbs heat). Thus, the optical element 1812 and its payload assembly 1810 will attempt to increase in size relative to the payload assembly's attachment points to the base assembly 1808. Because the inner internal flexure assemblies 1816A-1816C allow for or compensate temperature-induced distortions along the lines of action 1908A-1908C, the expanding optical element 1812 and its payload assembly 1810 will not cause any warping or stresses to the base assembly 1808. The optical element 1812 and the payload assembly 1810 will be at substantially the same temperature and hence will generate no internal stresses or distortions (other than simple expansion). The inner internal flexure assemblies 1816A-1816C also maintain the center of the expanding payload assembly 1810 (and optical element 1812) at the centroid 1910 of the flexure systems lines-of-action. In some applications, maintaining centration of the expanding optical element 1812 is critical. For example, an incident laser beam may be required to remain at a certain spatial position on a diode. The spatial position for instance, is the center of the diode. With a thermal compensation flexure assembly in FIG. 19, the laser beam will remain at its spatial position even when the diode expands or contracts. If the diode expands or contracts, the neutral point is the center of the diode, and the center of the diode will not move spatially laterally, relative to the base assembly 1808. Chuck Array FIG. 20 is a three-dimensional view of one embodiment of a micromachined alignment assembly 2000, which comprises a base assembly 2006 and a payload assembly 2004 (also called “chuck arrays” or “wafers” or “planar objects”). In another embodiment the top structure 2004 may be the base, and the bottom structure 2006 may be the payload. The micromachined alignment assembly 2000 in FIG. 20 may constitute a view of one-third of a two-piece, ring-shaped alignment assembly. The base assembly 2006 and payload assembly 2004 each comprise an array of micromachined chucks or holes 2002 for restraining and aligning arrays of optical elements 2008, such as mounted lenses, fibers, or mirrors. The chucks 2002 may be formed by one or more processes described in the above-referenced U.S. patent application, entitled “OPTICAL ELEMENT SUPPORT STRUCTURE AND METHODS OF USING AND MAKING THE SAME” (Attorney Docket No. M-11130 US), which is hereby incorporated by reference in its entirety. FIG. 21 is an enlarged three-dimensional view 2100 of one part of the micromachined alignment assembly 2000 (“chuck array”) in FIG. 20. FIG. 21 illustrates a bipod-style connecting element 2108 (e.g., a planar structure) with two tabs 2102A-2102B for pseudo-kinematic (low distortion) or redundant (planarity enforcing) attachment of the base assembly 2006 and the payload assembly 2004. An alignment assembly may comprise two ring-shaped structures, which are partially shown in FIGS. 20 and 21, and a plurality of bipod-style connecting elements (e.g., three), such as the bipod-style connecting element 2108 in FIG. 21. In one embodiment, each connecting tab 2102A, 2102B in FIG. 21 is a planar structure with two stiff DOFs. DOFs 2110, 2112, 2114 are controlled at the payload assembly 2004. DOFs 2110, 2114 are used by the payload assembly 2004, and DOF 2112 is used by the connector tab 2102A. DOFs 2116, 2118 are redundant, which may or may not be used. DOF 2116 may be used by the payload assembly 2004 to enforce planarity, and DOF 2118 may be used by the connecting structure 2108 to enforce planarity. With three bipod-style connecting elements, such as the bipod-style connecting element 2108 in FIG. 21, the payload assembly 2004 and the base assembly 2006 may be supported by a total of six stiff DOFs. The connector tabs 2102A-2102B have internal flexure assemblies 2104A, 2104B that provide compliance in the vertical direction for preloader stages 2106A, 2106B, which in turn may be used (with a preloader pin, not shown) to provide preload to controlled DOFs 2110 and 2116. Similar to the vertical preload example of FIG. 9, a possibly redundant rotational constraint normal to the plane of connecting structure 2108 may also be created. The micromachined alignment assembly 2000 shown in FIGS. 20 and 21 may accurately control the lateral positions of the payload assembly 2004 with respect to the base assembly 2006, and thus control the lateral positions (desired orientation) of upper and lower portions of the optical elements 2008. In one embodiment, each bipod-style connecting element 2108 utilizes neighboring flexure systems in the base and payload wafers 2006, 2004 to provide preloading for the other DOFs indicated in FIG. 21. For example, a first connecting tab 2102A of the bipod-style connecting element 2108 in FIG. 21 has neighboring flexure systems 2120A and 2120B. FIG. 11 shows a top view of a connecting tab 1106 that may represent connecting tab 2102A in FIG. 21. The two flexure systems 2120A and 2120B, together with their respective preloader stages and preloader pins (not shown) allow for application of preload to control DOFs 2112 and 2114. Flexure systems 2120C, 2120D provide similar capability at the attachment of 2108 to the base assembly 2006. The connecting structures between two objects (e.g., a base and a payload) disclosed herein may be pseudo-kinematically supported, which allows the connecting structures to be used for precision positioning and distortion free support of optical components. Optical Element Support Structure FIG. 22 is a three-dimensional view of one embodiment of an assembly 2200, which comprises a first structure 2210 (e.g., a base assembly or a payload assembly), a plurality of connecting elements 2202A-2202C and a second structure 2208 (e.g., a base assembly, a payload assembly or an optical element, such as a mirror). In one configuration, the assembly 2200 may be an all-silicon fold mirror. Other embodiments of the assembly 2200 may have less than three or more than three connecting elements. The connecting elements 2202A-2202C have redundant attachment points 2204A-2204F on one end and pseudo-kinematic attachment points 2206A-2206C on the other end. The six redundant attachment points 2204A-2204F may connect to the first structure 2210. The three pseudo-kinematic attachment points 2206A-2206C may connect to the second structure 2208. Other embodiments of the connecting elements 2202A-2202C may have less or more attachment points. FIG. 23 is an enlarged view of a redundant attachment point 2204A of one connecting element 2202A in FIG. 22. The redundant attachment points 2204A-2204F of the connecting elements 2202A-2202C in FIG. 22 attach to the base assembly 2210 collectively with more than six stiff DOFs. In FIG. 23, the redundant attachment point 2204A is connected to the base assembly 2210 with two possibly stiff DOFs 2302A-2302B, in addition to the DOFs (e.g., three translations) used for pseudo-kinematic attachment. Similarly, the redundant attachment points 2204B-2204F are each connected to the base assembly 2210 with two additional possibly stiff DOFs (not shown). Therefore, the three connecting elements 2202A-2202C attach to the base assembly 2210 with twelve additional possibly stiff DOFs. In some applications, other designs for the connecting elements may be used to attach the base assembly in more than six DOFs. For example, a connecting element may have three redundant attachment points. The rationale for allowing these redundant DOFs in this assembly is the same as discussed in the section “Redundant Elements for Additional Stiffness/Planarity Enforcement” (e.g., enforcing the planarity of the base and/or connecting elements). FIG. 24 is an enlarged view of a pseudo-kinematic attachment point 2206A (also called mounting tab) of one connecting element 2202A in FIG. 22. The attachment point 2206A in FIG. 24 may embody some or all of the principles of kinematic support and position control described above. The pseudo-kinematic attachment points 2206A-2206C of the connecting elements 2202A-2202C in FIG. 22 attach to the optical element 2208 collectively with six stiff DOFs. FIG. 24 illustrates one pseudo-kinematic attachment point 2206A with two stiff DOFs 2402A, 2402B. Similarly, the other pseudo-kinematic attachment points 2206B, 2206C are connected to the optical element 2208, each with two stiff DOFs (not shown). In one embodiment, each pseudo-kinematic attachment point 2206 has a flexure system 2408A and 2408B (FIG. 24) that is designed to provide an appropriate stiffness to form a ball joint with stiff DOFs 2402A, 2402B, 2406. DOFs 2402A, 2402B pseudo-kinematically support the mirror wafer 2208, and DOF 2406 is a constraint borrowed back from the optical element 2208 to support the end of the connecting element 2202A. In one embodiment, the pseudo-kinematic attachment point 2206A uses positive preloaders (or preloading stage) to attach the connecting element 2202A to the optical element 2208 without deadband, such that DOFs 2402A, 2402B, 2406 are precisely specified and controlled (i.e., possess high stiffness). In one configuration, the pseudo-kinematic attachment point 2206A uses three preloaders. One preloader 2412 applies a preload against a surface of the pseudo-kinematic attachment point 2206A using a preloader pin (not shown) to precisely specify and control DOF 2406. Another preloader 2414 applies a preload against another surface (e.g., end of the tab in the slot) of the pseudo-kinematic attachment point 2206A without a pin (see FIGS. 9, 11) to precisely specify and control DOF 2402B. A vertical preloader (not shown) in an upper portion of the attachment point 2206A that protrudes above the optical element 2208 is similar to the preloader stage 2304 in the redundant attachment point 2204A in FIG. 23. The vertical preloader stage in the pseudo-kinematic attachment point 2206A provides a preload in DOF 2402A. The vertical preloader stage uses a preloader pin. The flexure system 2405 has two flexure elements 2408A-2408B that form a bipod-like structure. The two flexure elements 2408A-2408B intersect at a virtual point in the pseudo-kinematic attachment point 2206A and hence form a “ball joint” as previously described. In one embodiment, the flexure system 2405 in FIG. 24 is recessed using an extra micromachining step (an etch defined by the square area 2404), to decrease the depth 2410 of the flexure elements 2408A-2408B. The flexure blade depth 2410 is then variable and not fixed as the thickness of the wafer. Thus, flexure properties may be more readily tailored to achieve a desired pseudo-kinematic stiffness connectivity. For example, if the flexure elements 2408A-2408B are thinned sufficiently, they would behave more like rods, and thus more perfectly constrain only two DOFs, i.e., have larger separation of stiffness between desired and undesired constraint DOFs. The connecting elements 2202A-2202C in FIG. 22 may be fabricated using the manufacturing procedures described herein. For example, lithography and micromachining can fabricate the connecting elements 2202A-2202C with high intrinsic precision. In one embodiment, a recessed flexure system (e.g., 2408A and 2408B in FIG. 24) in each connecting element 2202 is formed by a patterning process, such as lithography, that forms a desired pattern, such as a rectangle, of the recessed flexure system 2405 on one side of a substrate wafer. Then the rectangular area is partially etched through the substrate wafer until a desired depth 2410 for the flexure elements 2408A-2408B remains. The flexure system 2405 could then be etched from the other side using an appropriate mask pattern to form the flexure elements 2408A-2408B. In another embodiment, a patterning process such as lithography may be used to form a desired pattern of the flexure elements 2408A-2408B on a substrate wafer. Next, a micromachining process such as an etching process may be used to etch through the substrate wafer to a pre-determined depth for thinning down the depth 2410 of the flexure elements 2406A-2406B. After the micromachining process, the substrate wafer is cleansed. Next, the substrate wafer may be subjected to a second patterning process. Then, the substrate wafer may be subjected to a second micromachining process to etch through the whole substrate wafer. Finally, the substrate wafer is cleansed and then assembled to provide the desired micromachined passive alignment assembly. Megastack FIG. 25 is a three-dimensional view of one embodiment of a megastack structure 2500. The megastack structure comprises a base plate 2502 and one or more side plates 2504A, 2504B. The configuration with one sideplate 2504 may be referred to as an “L-type megastack,” and the configuration with two side plates 2504A, 2504B, shown in FIG. 25, may be referred to herein as a “C-type megastack.” The megastack structure 2500 enables precise dimensional support of an arbitrarily large number of payload assemblies 2506, which may comprise silicon wafers with MEMs devices or integral or mounted optical devices. Optical elements 2508 may be mounted, restrained, and/or aligned on a payload assembly 2506. In some applications, a side plate 2504 may also serve as a payload assembly that mounts, restrains, and/or aligns optical elements. As shown in FIG. 25, the megastack structure 2500 has precisely-formed attachment points 2510A-2510C. (also called “slots”) to support and align each payload assembly 2506. Each attachment point 2510 provides two-DOF positioning control in the C type megastack configuration to attain a pseudo-kinematic support condition. The side plates 2504A-2504B may or may not be kinematically attached to the base plate 2502. As shown in FIG. 25, DOFs 2512A, 2512B, 2514, 2516, 2518A, 2518B are used to kinematically support the side plate 2504A. The DOF 2514 is “borrowed” from a payload assembly 2506 (or other structural element) to create a kinematic support condition. The side plate 2504A is also attached to the base plate 2502 via redundant DOFs 2520A-2520B. The redundant DOFs 2520A, 2520B may be allowable because their directions support the attached plates 2504A-2504B in DOFs that have an associated soft stiffness of plate out-of-plane bending. The redundant DOFs 2520A, 2520B may therefore preserve the flatness in both the base plate 2502 and the side plate 2504A. In other embodiments, it may be desirable to have a degenerate or a redundant support system for a C-type or L-type megastack structure 2500. If a degenerate support system is desired, the megastack structure 2500 may support and/or align the payload assembly 2506 using less than three attachment points 2510. If a redundant support system is desired, the megastack structure 2500 may support and/or align the payload assembly 2506 using more than three attachment points 2510. The attachment points 2510A-2510C (FIG. 25) are geometrically positioned such that two attachment points 2510A and 2510C are elevated above the base plate 2502, and one attachment point 2510B is in the plane of the base plate 2502. This geometrical attachment arrangement, or other similar arrangements, when combined with the specific directions of local DOF support, produce a non-degenerate, non-redundant, pseudo-kinematic support for a payload plate 2506. As another example, an L-type megastack may have two attachments points on a base plate and one attachment point elevated above the baseplate plane on a sideplate. Here the local DOF supported at each attachment point are in different directions from the pictured C-type megastack 2500 in FIG. 25. FIG. 26 is an enlarged view of some attachment points 2510A, 2510B of the side plate 2504A and the base plate 2502 in FIG. 25. Given the geometric position of the attachment points 2510A-2510C (FIG. 25), a C-type megastack payload assembly structure 2506 is pseudo-kinematically supported by two precisely-controlled DOFs 2602A, 2602B (FIG. 26) from attachment point 2510A, two DOFs 2604A, 2604B from attachment point 2510B, and two DOFs (not shown) from attachment point 2510C (FIG. 25). The two DOFs (not shown) from attachment point 2510C are similar to the two DOFs 2602A, 2602B (FIG. 26) from attachment point 2510A. In FIGS. 25 and 26, flexure systems with integral preloaders 2606A, 2606B, 2608A, 2808B may be implemented for maximum positioning precision. For example, preloader 2608B preloads a tapered tab (not shown) of a payload assembly 2506 to seat the tab against the slot 2510B in DOF 2604A, which forms a tab-in-slot configuration as shown in FIGS. 9 and 11. Preloader 2608A may use a tapered pin (not shown) to preload the tab (not shown) of a payload assembly 2506 against the slot 2510B in DOF 2604B. Similarly, the preloaders 2606A, 2606B may preload a tab, such as tab 2610, in DOFs 2602B, 2602A, respectively. The tab 2610 may have a preloader 2612. FIG. 27 is the top view of the megastack structure 2500 in FIG. 25. FIG. 28 is the side view schematic of one embodiment of a side plate, such as the sideplate 2504A in FIG. 25. The side plate 2802 in FIG. 28 is another example of planar positioning accuracy. The side plate 2802 has three slots 2804A-2804C for engaging three tabs 2806A-2806C of three payload assemblies, such as the payload wafer 2506 in FIG. 25. In FIG. 28, the slots 2804A-2804C are open-ended at a top side. In FIG. 25, the side plates 2504A, 2504B have slots 2510A, 25101B that are closed-ended at all sides and form a window opening in the side plates 2504A, 2504B. Similarly, the base 2502 in FIG. 25 has slots 2510B that are closed-ended at all sides and form a window opening in the base assembly 2502. The side plate 2802 in FIG. 28 may precisely control two DOFs on each of the three tabs 2806A-2806C of attached payload wafers (FIG. 25). The vertical edges 2810A-2810C of the slots 2804A-2804C may allow precise definition of the horizontal separation 2808A, 2808B between the three tabs 2806A-2806C (even more precise if the tabs 2806A-2806C are preloaded against the slots 2810A-2810C). The horizontal (bottom) edges of the slots 2804A-2804C provide a vertical reference between the tabs 2806A-2806C (again, even more precise when the tabs 2806A-2806C are preloaded against the bottom edges). The side plate 2802 in FIG. 28 may be used in conjunction with one or two other similar objects (each appropriately connected to the others) to completely define the positions and orientations of three payload wafers, which each have a plurality of tabs (FIG. 28 shows tabs 2806A-2806C of three payload wafers). In some applications, it is desirable to have the side plate 2802 with slots 2804A-2804C that are equidistant from one another, as shown by distances 2808A-2808B. An equidistant arrangement may allow proper alignment of the payload assemblies. FIG. 29 is a three-dimensional view of a complete megastack structure 2900, which is shown partially in FIG. 25, with a plurality of payload assemblies 2902A-2902G. The complete megastack structure 2900 in FIG. 29 comprises side plates 2504A, 2504B, a base plate 2502, tabs (such as tab 2610), slots, internal flexure assemblies, payload assemblies 2902A-2902G, optical elements (collectively referred to as “components”), as described above. The attachment mechanisms maintain the complete megastack structure 2900 in a pseudo-kinematic state. FIG. 30 is a three-dimensional bottom view of the complete megastack structure 2900 in FIG. 29. FIG. 30 shows one side plate 2504B, the base plate 2502, one payload assembly 2506, bottom tabs 3002A-3002C of the side plate 2504B and bottom tabs 3004A-3004C of three payload assemblies. The bottom tabs 3002A-3002C and bottom tabs 3004A-3004C protrude from the bottom surface of the base plate 2502. The complete megastack structure 2900 in FIGS. 29 and 30 may be fabricated using the same manufacturing procedures described herein. For example, using the lithography process and the micromachining process to fabricate the tabs, slots, internal flexure assemblies, payload assemblies, sideplate assemblies, and base assemblies. FIG. 31 illustrates one method of designing the three-dimensional structures and assemblies described above and translating the designs into masks for high precision microlithography/photolithography. The actions described in FIG. 31 may be performed in the order as shown or in alternative orders. Some of the actions may be skipped or combined with other actions. The method of FIG. 31 may include other actions in addition to or instead of the actions shown. FIG. 32 illustrates one method of making high precision, three-dimensional structures described above. The actions described in FIG. 32 may be performed in the order as shown or in alternative orders. Some of the actions may be skipped or combined with other actions. The method of FIG. 32 may include other actions in addition to or instead of the actions shown. FIG. 33 illustrates one method of assembling three-dimensional structures described above from planar parts. The actions described in FIG. 33 may be performed in the order as shown or in alternative orders. Some of the actions may be skipped or combined with other actions. The method of FIG. 33 may include other actions in addition to or instead of the actions shown. The above-described embodiments of the present invention are merely meant to be illustrative and not limiting. Various changes and modifications may be made without departing from the invention in its broader aspects. The appended claims encompass such changes and modifications within the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates generally to optical devices, and more particularly to optical element alignment assemblies and methods of making the same. 2. Description of the Related Art An optical component, such as a mirror, lens or fiber, in an optical instrument or device, such as an optical switch, should be accurately located/positioned with respect to another optical component in order for the optical instrument or device to function properly. Thus, optical devices may require their components to be placed with exacting tolerances to fulfill design objectives. Conventional passive alignment assemblies for MicroElectroMechanical System (MEMS) devices are typically planar in nature and only align local elements, e.g., a fiber and ball lens collimator, where the two components are within a few millimeters of each other. Alignments over larger distances (e.g., greater than five millimeters), and three-dimensional optical systems typically use conventionally machined components. Such assemblies often fail to align optical components with high intrinsic precision. | <SOH> SUMMARY OF THE INVENTION <EOH>Components generally need to be located in three dimensions, i.e., distributed in a volume of space, and have three rotations specified and/or controlled. Components located in a plane (two dimensions) with three or fewer rotations specified and/or controlled are a subset of the general case. Other design objectives may include: (1) locate components without induced strains, either from the process of mounting or through bulk temperature changes of constituent parts, and/or (2) support components as rigidly as possible. In accordance with the present invention, alignment assemblies and methods of using and making the assemblies are provided. An important advantage of several embodiments of the invention is to completely orient one body with respect to another body to a high degree of precision by providing (1) precise mating features between bodies and connecting elements, and (2) precise distances between these features on all bodies and connecting elements. In one embodiment, the alignment assemblies are passive, kinematic or non-kinematic, and micromachined. “Passive alignment” means the various parts or devices to be assembled have mating features such that when these features are engaged with each other, the correct alignment (typically optical) is attained. In some instances, the engagement of these mating features permanently controls the alignment. In other instances, some type of fixture will hold the parts with their mating features engaged while some additional fixation, e.g., glue or bolt, is added to make the engagement permanent. For comparison, in “active” alignment, two parts or devices are maneuvered with respect to each other by some motion control mechanism, e.g., a motorized motion stage, shim set, etc., in one or more directions or degrees-of-freedom (DOF) until some metric, e.g., light through-put, optical beam quality, etc., is within a specified tolerance. At that point, the two parts are fixed rigidly with respect to each other by some means, e.g., glue, solder, bolt. As defined and used herein, “kinematic mounting” relates to attaching two bodies, which may be called a base assembly or a payload assembly, together by forming a structural path and creating stiffness between the two bodies in six, and only six, independent degrees of freedom (“DOFs”) or directions. Each degree of freedom (DOF) kinematically controlled between two bodies is also a position defined, i.e., a specific value of that DOF, as a linear measurement, may be maintained. Six DOFs are desired because the location of any object in space is defined by three orthogonal coordinates, and the attitude of the object is defined by three orthogonal rotations. A kinematic support has the advantage of being stiff, yet any strains or distortions in the base assembly are not communicated to the payload assembly. Thus, any sensitive optical alignments are not altered in the payload assembly if the base assembly undergoes deformation due to applied loads or bulk temperature changes. In one embodiment, it is desirable to tailor a DOF based on the configuration of a “pseudo-kinematic” support. “Pseudo-kinematic” means that although there may be many DOFs connecting at least two bodies, such as two micromachined passive alignment assemblies, in a practical attachment scheme, the DOFs can be tailored such that only six DOFs have a relatively high stiffness, and substantially all other DOFs have a relatively low stiffness. Thus, true “kinematic” support means only 6 stiff DOFs connecting two parts, and no other stiffness paths exist. “Pseudo-kinematic” means there are 6 DOFs with relatively high stiffness, and possibly many more with much lower stiffness (typically two to three orders of magnitude less). In some applications, it is desirable to have pseudo-kinematic DOFs with relatively low stiffness to be two to three orders of magnitude lower than DOFs with relatively high stiffness. DOFs with different levels of stiffness may be accomplished using a flexure system to relieve stiffness in unwanted DOFs. Depending on the cross-sectional properties of elements in the flexure system, connecting elements between two bodies may attain the desired stiffness connectivities. The alignment assemblies and methods of making the assemblies according to the invention may provide a number of advantages. For example, the micromachined passive alignment assemblies may be made with high intrinsic precision. Micromachining processes may form three-dimensional structures from a substrate wafer with high accuracy. In several embodiments, one micromachined passive alignment assembly may be oriented and spaced with respect to another assembly (e.g., with connecting elements) with lithographic precision, e.g., three-dimensional translational positioning to less than one micron and three-dimensional angular positioning to less than five arcseconds for an assembly with a 50-mm characteristic dimension. The methods according to the invention may construct mating surfaces on micromachined passive alignment assemblies, such as a base assembly and a payload assembly, to control six independent DOFs between the assemblies and allow complete, high-precision specification of position and attitude. In some applications, it is desirable to have micromachined connecting elements with counterpart mating surfaces to mate with the mating surfaces on the base and payload assemblies. The accuracy of micromachined passive alignment assemblies may be fully realized if there is a positive contact between a pair of mating features. Thus, some form of preload or force may be applied to maintain compressive contact between the pair of mating features. An external force may be applied to preload mating surfaces to contact each other prior to gluing. Glues that shrink on cure may be used to maintain the preload across mating surfaces after assembly. In addition to or instead of an external force, any of the structural elements being assembled may have an internal flexure assembly that applies an intemally-reacted force (preload). The internal flexure assembly may seat mating surfaces without a deadband. In one embodiment, the internal flexure assembly comprises a set of double parallel motion flexures, a preloader stage, and a hole on one side of the preloader stage for inserting a separate preloader pin. When the preloader pin is inserted into the hole of the internal flexure assembly, the preloader stage deflects and exerts a force on the pin, which exerts a preload against a mating surface. After the micromachined passive alignment assemblies are assembled, the mating surfaces may be glued or bonded if desired. A connecting element may be configured to restrain the base assembly and the payload assembly with one or more desired DOFs. In some embodiments, a “degenerate” support or connecting element may be used where less than six constrained DOFs between a base and payload are desired. The degenerate support may allow some trajectory (i.e., a combination of Cartesian DOFs) of a payload assembly relative to a base assembly to be unconstrained. A “redundant” support or connecting element may be used in applications where more than six DOFs are desired. The redundant support reinforces the base and payload assemblies and maintains their flatness. As another example, a micromachined passive alignment assembly may have thermal compensation flexure assemblies for maintaining centration of optical elements in the presence of large bulk or local temperature differences. The optical elements may then be attached to at least three pads supported by these flexure assemblies to effect this stable positioning. In some applications, it is desirable to position a plurality of optical elements in a precise pattern in the presence of large bulk or local temperature differences. In some of these applications, it may be desirable to position a plurality of thermal compensation flexure assemblies concentric with respect to the center of an opening and equidistant with respect to each other. One aspect of the invention relates to an assembly configured to support at least one optical element to a pre-determined position. The assembly comprises a first micromachined structure having at least a first mating part and a second micromachined structure having at least a second mating part. The second mating part is configured to contact the first mating part to constrain the second micromachined structure with respect to the first micromachined structure. The second micromachined structure is configured to support at least one optical element. In one embodiment, the second mating part is configured to contact the first mating part to precisely position the second micromachined structure with respect to the first micromachined structure. In one embodiment, the optical element is then precisely positioned with respect to the first micromachined structure. In one embodiment, the first micromachined structure also supports one or more optical elements. Another aspect of the invention relates to an assembly configured to support at least one optical element. The assembly comprises a first micromachined structure having at least a first attachment point and a second micromachined structure having at least a second attachment point. The second attachment point is configured to contact the first attachment point to restrain the second micromachined structure with respect to the first micromachined structure in at least one degree-of-freedom (DOF). The second micromachined structure is configured to support at least one optical element at a pre-determined position. In one embodiment, the second attachment point is configured to contact the first attachment point to restrain and align the second micromachined structure with respect to the first micromachined structure. In one embodiment, the optical element is then aligned to a pre-determined position with respect to the first micromachined structure. In one embodiment, the first micromachined structure also supports one or more optical elements. Another aspect of the invention relates to a method of making an assembly configured to position an optical element to a pre-determined position. The method comprises using lithography to form a first pattern and a second pattern on a substrate for a first structure and a second structure. The first pattern outlines a first mating part of the first structure. The second pattern outlines a second mating part of the second structure. The method comprises etching the substrate to form the first and second structures according to the first and second patterns. The second mating part is configured to contact the first mating part to constrain the second structure with respect to the first structure. The second structure is configured to position at least one optical element. One aspect of the invention relates to an assembly configured to support at least one optical element to a pre-determined position. The assembly comprises a micromachined base, a payload and a connecting structure. The base has a first mating part. The payload is configured to position the optical element. The payload has a second mating part. The connecting structure is configured to contact the first mating part of the base and the second mating part of the payload. The connecting structure constrains the payload in about five to about six degrees of freedom with respect to the base. In one embodiment, the base also positions an optical element. Another aspect of the invention relates to an assembly configured to position at least one optical element to a pre-determined position. The assembly comprises a base plate and at least one side plate configured to connect to the base plate. The base plate and the side plate are configured to support a plurality of payload plates. Each payload plate is configured to connect to the side plate and to the base plate. Each payload plate is configured to position at least one optical element. Another aspect of the invention relates to a method of making an assembly configured to position at least one optical element to a pre-determined position. The method comprises using lithography to form a first pattern, a second pattern and a third pattern on a substrate for a base, a payload and a connecting structure. The first pattern outlines a first mating part of the base. The second pattern outlines a second mating part of the payload. The third pattern outlines third and fourth mating parts of the connecting structure. The method further comprises etching the substrate to form the base, the payload and the connecting structure according to the first, second and third patterns. The connecting structure is configured to contact the first mating part of the base and the second mating part of the payload. The connecting structure constrains the payload in about five to about six degrees of freedom with respect to the base. The payload is configured to position an optical element. One aspect of the invention relates to a micromachined flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of parallel motion flexures and a preloader stage coupled to the set of parallel motion flexures. The set of parallel motion flexures allows the preloader stage to deflect away from a second structure of the optical element alignment assembly and apply a load against the second structure to constrain the second structure in at least one degree of freedom with respect to the first structure. Another aspect of the invention relates to a micromachined thermal compensation flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of collinear flexures and a center stage coupled to the set of collinear flexures. The set of collinear flexures and the center stage are configured to limit distortions in one direction due to a temperature change in the first structure from affecting an optical element supported by the first structure. In one embodiment, three or more such assemblies may completely support a second structure, e.g., an optical element or assembly, with respect to the first structure such that there are minimal internal stresses, and hence distortions, in the second structure in the presence of bulk temperature changes or substantial temperature differences between the structures. Another aspect of the invention relates to a micromachined strain isolation flexure assembly formed in a first structure that is a part of an optical element alignment assembly. The flexure assembly comprises a set of collinear flexures and a center stage coupled to the set of collinear flexures. The set of collinear flexures and the center stage are configured to limit strains in one direction in the first structure from transferring to a second structure. Three or more such assemblies may completely isolate a second structure, e.g., an optical element or assembly, with respect to the first structure such that there are minimal internal stresses, and hence distortions, in the second structure in the presence of mechanically or inertially induced distortions in the first structure. Another aspect of the invention relates to a method of making a micromachined flexure assembly in a structure that is a part of an optical element alignment assembly. The method comprises using lithography to form a pattern on a substrate for the structure. The pattern outlines a set of collinear flexures and a center stage coupled to the set of collinear flexures. The method further comprises etching the substrate to form the structure according to the pattern. | 20050118 | 20060926 | 20050609 | 64781.0 | 0 | LEE, JOHN D | BASE, PAYLOAD AND CONNECTING STRUCTURE AND METHODS OF MAKING THE SAME | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,022 | ACCEPTED | Face detecting apparatus and method | A process time is shortened while a face detection precision is maintained high. A face detection unit for extracting a face area of a photographic subject from an image taken with a digital camera or the like includes a unit for acquiring focussing area information in an image area from image data and accessory information of image data regarding photographic conditions and the like, a unit for determining a face detection area in the image area in accordance with the focussing area information, and a unit for executing a face detection process not for a whole image area but partially for a face. | 1. A feature detecting apparatus for extracting a feature of a photographic subject from an image, the apparatus comprising: means for acquiring accessory information associated with image data; means for determining a plurality of feature detection area in an image area of the image on the basis of the accessory information; and means for executing a feature detection process in the feature detection areas according to a prescribed priority of order. 2. A face detecting apparatus for extracting a face area of a photographic subject from an image, the apparatus comprising: means for acquiring accessory information associated with image data; means for determining a plurality of face detection area in an image area of the image on the basis of the accessory information; and means for executing a face detection process in the face detection areas according to a prescribed priority of order. 3. The face detecting apparatus according to claim 2, wherein said means for determining a face detection area includes means for acquiring focussing area information from said accessory information, and determines said face detection area on the basis of said focussing area information. 4. The face detecting apparatus according to claim 3, wherein said focussing area information includes “range finding frame number” and “used range finding frame”. 5. The face detecting apparatus according to claim 3, wherein said focussing area information includes “coordinate values”, and said means for determining a face detection area calculates the coordinate values of the face detection area on the basis of the “coordinate values”. 6. The face detecting apparatus according to claim 3, wherein said focussing area information includes photographic subject distance information, and said priority order is determined on the basis of the photographic subject distance information. 7. The face detecting apparatus according to claim 6, wherein said means for determining a face detection area determines a higher priority order as a photographic subject distance becomes shorter. 8. The face detecting apparatus for extracting a face area of a photographic subject from an image, the apparatus comprising: means for acquiring accessory information associated with image data; means for acquiring assistance mode information during photographing from said accessory information: means for determines the face detection area on the basis of the assistance mode information: and means for executing a face detection process in the face detection areas. 9. The face detecting apparatus according to claim 8, wherein the assistance mode information is character string information indicative of photographic conditions, and said means for determining a face detection determines as the face detection area an area designating portrait photographing in a guide display displayed in an assistance mode on the basis of the character string information. 10. An image processing system comprising an image processing apparatus including the face detecting apparatus as recited in claim 2, a digital still camera and a display unit. 11. A feature detecting method for extracting a feature of a photographic subject from an image, the method comprising: a first step of acquiring at least a portion of accessory information associated with image data; a second step of determining a plurality of feature detection area in an image area of the image, on the basis of the information acquired at said first step; a third step of investing a priority of order to the feature detection areas: and a forth step of executing a feature detection process in the feature detection area according to the priority of order. 12. A face detecting method for extracting a face area of a photographic subject from an image, the method comprising: a first step of acquiring at least a portion of accessory information associated with image data; a second step of determining a plurality of face detection area in an image area of the image, on the basis of the information acquired at said first step; a third step of investing a priority of order to the face detection areas: and a forth step of executing a face detection process in the face detection area according to the priority order. 13. The face detecting method according to claim 12, wherein the information acquired at said first step includes at least one pieces of focussing area information in the image area and assistance mode information during photographing. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a means for extracting a photographic subject from still image data, and more particularly to a face detecting apparatus and method. 2. Related Background Art Digital still cameras and digital video cameras are prevailing rapidly nowadays. Along with this, there are increasing demands for tools such as a tool for processing images photographed with these photographing apparatuses to provide a high image quality. In the high image quality process, for example, a face detection process is executed for an image, and if there is a human face, a correction amount is determined basing upon the detected face. This method is widely known. Most of the process time required for the high image quality process is occupied by the face detection process time. This process time has been long desired to be shortened. Several means for improving a face detection efficiency have been proposed. For example, Japanese Patent Application Laid-Open No. 2003-163827 (no corresponding U.S. application) proposes an approach by which a photographing apparatus executes a pixel thinning process for a whole image in accordance with a photographing mode and a photographic subject magnification factor, and changes the number of divided blocks to be subjected to the face detection process. With this approach, a face detection precision is changed for each photographed image to improve the process efficiency. According to the invention described in Japanese Patent Application Laid-Open No. 2003-163827, the face detection process is executed for the whole area of an image. There arises therefore the problem that an area subjected to the face detection process increases greatly as the image data amount increases, and the process time prolongs. Another problem resides in that the detection precision is degraded if the number of thinned pixels is increased in order to shorten the process time. SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described problems and aims to shorten the process time by executing the face detection process more efficiently, while the detection precision is maintained high. Especially, the present invention aims to executing the face detection process efficiently in the case of a portrait photographing with a plurality of faces. In order to achieve the above object, a face detecting apparatus of the present invention for extracting a face area of a photographic subject from an image on the basis of image data and accessory information associated with the image data comprises: means for determining a plurality of face detection area in an image area of the image in accordance with the accessory information; and means for executing a face detection process in the determined face detection area according to a prescribed priority of order. According to the present invention, since a face detection area is determined by using accessary information such as photographic conditions, a process time required to detect a face can be shortened. Furthermore, in a system for processing an image in accordance with a face detection result, the process time of the whole system can be shortened because of a shortened face detection process time. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the structure of an image processing system adopting face detecting means of the present invention. FIG. 2 is a diagram illustrating an image (picture) file format of a digital still camera (DSC). FIG. 3 is a diagram illustrating that a user of DSC moves a focussing evaluation area. FIG. 4 is a diagram showing an example of a display screen of a liquid crystal monitor mounted on the back of DSC. FIG. 5 is a flow chart illustrating the operation of an image processing apparatus. FIG. 6 is a diagram explaining calculation of a gamma value to be used for correction processing. FIG. 7 is a flow chart illustrating the detailed operation of setting a face detection area. FIG. 8 is a diagram showing the relation between a range finding frame and image data. FIG. 9 is a diagram illustrating an operation of dividing an image in accordance with the number of range finding frames and determining a face detection area by using a range finding position. FIG. 10 is a diagram illustrating an operation of determining a face detection area by adding an offset value to a range finding frame. FIG. 11 is a diagram showing the relation between a range finding frame and image data in a system according to a second embodiment. FIG. 12 is a diagram showing a guide display displayed in an assistance mode on a liquid crystal monitor mounted on the back of DSC in a system according to a third embodiment. FIG. 13 is a diagram showing an example of a display screen of the liquid crystal monitor in the assistance mode. FIG. 14 is a flow chart illustrating an operation of setting a face detection area in a system according to a fourth embodiment. FIG. 15 is a diagram showing a face detection area in the system of the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First Embodiment A face detecting means of the present invention is applied to an image processing system such as shown in FIG. 1. The image processing system 100 shown in FIG. 1 is constituted of a digital still camera 101 (hereinafter written as DSC), a image processing apparatus 104 and a display unit 115. DSC 101 is constituted of a photographic condition setup unit 102 for setting photographic conditions and a record unit 103 for recording photographed image data during photographing. The photographic condition setup unit 102 sets various photographic conditions necessary for photographing. A user can set various conditions such as a photographic scene, a white balance mode, and a flash on/off, by operating buttons on DSC 101. The record unit 103 generates image data including photographed image data and accessory information of photographic conditions, and records it. A recording medium may be a memory built in DSC 101 or a detachable external medium. An image file format to be used for recording image data is in conformity with, for example, Exchangeable Image File Format (Exif). As shown in FIG. 2, the image file format is constituted of a tag region 201 in which the accessory information, i.e., photographic condition data, is recorded and an image (picture) data region 202 in which photographed image data is stored. The photographic condition data is recorded in the tag region 201 at positions starting from a predetermined offset position from the top, and contains, for example, the contents of TagNo.=0 to 6. TagNo.=0 is information of a photographic scene type. For a “landscape mode” of DSC, a value representative of the “landscape mode” is stored in TagNo.=0. The photographic scene type is not limited only to this, but a “standard”, “portrait”, “night scenery” or the like may be designated. TagNo.=1 is information of white balance. For an “automatic white balance” of DSC, a value representative of automatic white balance setup is stored in TagNo.=1. For manual white balance setup, a value representative of manual setup is stored. TagNo.=2 is information of an exposure mode. For “automatic exposure” of DSC, a value representative of automatically controlled parameter exposure setup is stored in TagNo.=2. For “manual exposure” or “automatic bracket” setup, a corresponding value is stored. TagNo.=3 is information of a flash. For “flash emission” of DSC, a value representative of flash emission is stored in TagNo.=3. A value representative of detailed information such as “automatic emission mode” and “red-eye reduction mode” of the flash emission may also be stored. TagNo.=4 is information of a focussing area. Stored in TagNo.=4 are values representative of “range finding frame number”, “used range finding frame” and “photographic subject distance in each range finding frame” respectively used for focussing control of DSC. Detailed description of focussing control for photographing is omitted because this does not constitute the main characteristics of the present invention. With this focussing control, for example, a blur amount of a photographed image in a predetermined focussing evaluation area is calculated and the lens position is controlled so that the blur amount becomes minimum. This focussing control is described, for example, in Japanese Patent Applicaion Laid-Open No. 2003-163827. A focussing control method such as shown in FIG. 3 is also known by which a user moves a focussing evaluation position 301 to a desired position and determines the focussing evaluation area in accordance with the focussing evaluation position. A person or an object like a person is often selected as the main photographic subject in order to determine the focussing evaluation area. When a user determines the focussing evaluation area, there is the tendency that the user determines the focussing evaluation area so as to focus on a person. FIG. 4 shows an example of a display screen of a liquid crystal monitor 401 mounted on the back of DSC. DSC prepares beforehand a range finding frame 402, and an emphasized range finding frame 403 is actually used for focussing control. TagNo.=5 is information of a maker name, and character string information representative of the maker name is stored therein. TagNo.=6 is information of a model name of DSC, and character string information representative of the model name is stored therein. Reverting to FIG. 1, the image processing apparatus 104 is made of, for example, a personal computer, activates predetermined application software, acquires image data from DSC 101, corrects it and outputs it. To this end, the image processing apparatus 101 is constituted of an input unit 105, a data analysis unit 106, a correction processing determination unit 112, a correction processing execution unit 113 and an output unit 114. The functions of the respective units 105 to 114 are realized by activating the application. The input unit 105 automatically recognizes a connection of DSC 101 to the image processing apparatus 104, and starts reading image data. Another configuration may be used in which image data is read after a user instruction is acknowledged. The data analysis unit 106 is constituted of an accessory information acquirement unit 107 for acquiring accessory information affixed to image data, a histogram analysis unit 108 for analyzing the feature of an image by generating a histogram from image data, and a face detection processing unit 109 which is the main characteristics of the present invention. The accessory information acquirement unit 107 acquires photographic condition data during photographing, such as a photographic scene type, a white balance, an exposure mode, a flash and a focussing area. The histogram analysis unit 108 generates a histogram of image data and calculates statistically a feature amount of an image. The feature amount is, for example, an average luminance, a luminance dispersion, and an average chroma, respectively of an image. The face detection processing unit 109 is constituted of a determination unit 110 for determining an area for which a face detection process is executed, and an execution unit 111 for executing the face detection process in accordance with a result obtained by the determination unit. The determination unit 110 determines the face detection area in an image area in accordance with focussing area information contained in the accessory information, in order to allow the execution unit 111 to be described later to execute. The detailed description will be given later. The execution unit 111 executes the face detection process for the setup area. Various methods for the face detection process have been proposed. For example, a face is detected by detecting one eye, generating a candidate of both eyes from the one eye and recognizing a face pattern. The correction processing determination unit 112 determines an image correction algorithm in accordance with an analysis result obtained by the data analysis unit 106. For example, the correction processing contents and correction procedure are acquired from the accessory information acquirement unit 107 and face detection processing unit 109, and the feature of the luminance distribution of an image is acquired from the histogram analysis unit 108, to thereby calculate correction parameters suitable for each of the correction processing contents. The correction processing contents include a gradation correction process, a contrast correction process, a color balance process, a chroma correction process, a contour emphasis process and the like. The correction processing execution unit 113 executes an image correction process for image data, in accordance with the image correction algorithm determined by the correction processing determination unit 112. The output unit 114 converts image data subjected to the correction process by the correction processing execution unit 113 into data capable of being displayed on the display unit, and outputs it to the display unit 115. The display unit 115 outputs and displays the image input from the output unit 114 in a desired form. Next, with reference to the flow chart of FIG. 5, description will be made on the operation of the image processing apparatus 104 of this embodiment. At Step 501, when DSC 101 is connected, the image processing apparatus 104 starts reading image (picture) data. At Step 502, a histogram is generated for the image data read at Step 501 to calculate a feature amount. The feature amount is an average luminance, a luminance dispersion and the like describe earlier. At Step 503, the accessory information representative of the photographic conditions is extracted from the image data read at Step 501. The accessory information may be written by using an application or the like after photographing. At Step 504, a face detection area is set in accordance with the focussing area information in the accessory information acquired at Step 503. If the flow returns to Step 504 because a face cannot be detected at Steps 505 and 506 to be described later, then a face detection area different from the already set face detection area is set again. For example, the first face detection area is set within the focussing area and the second face detection area is set in the area different from the focussing area to start a face detection process from the upper left of the image. At Step 505, the face detection process is executed for the face detection area set at Step 504. However, if it is judged that a person “exists”, i.e., the face was detected, this Step is terminated to advance to Step 506. At Step 506, the flow advances to Step 507 if it is judged at Step 505 that a person “exists” or the face detection process is completed for the whole image. In contrast, the flow returns to Step 504 to set again the face detection area, if it is judged that a person “does not exist” or the face detection process is not completed for the whole image. At Step 507, the correction process contents are selected in accordance with the accessory information during photographing and the face detection result acquired at Steps 503 to 506, and the correction processing amount is determined in accordance with the image feature amounts acquired at Step 502. In selecting the correction processing contents, the gradation correction process, contrast correction process, color balance process, chroma correction process, contour emphasis process or the like is selected in accordance with a combination of the photographic scene type, white balance, exposure mode, flash and the like respectively contained in the accessory information. The image processing apparatus 104 of the embodiment determines the correction processing contents by recognizing image data as a photographic scene type “person”, if Step 505 judges that a person “exists” and the photographic scene type is “standard”. This is because the correction process suitable for the photographic subject is to be used. Another configuration may be adopted by which the correction process for person is always used if the face detection results judge that a person “exists”, irrespective of the contents of the photographic scene type. After the correction processing contents are determined, a correction target value is determined from the accessory information and image feature amounts, to calculate the parameters to be used when the correction is executed. The correction target value is determined beforehand for each of the processing contents to be determined by a combination of accessory information, and preferably stored as a table in the image processing apparatus. Alternatively, the correction target value may be calculated from the feature amounts by using an equation. The parameters to be used when the correction is executed are calculated from the correction target value. For example, the gamma value for gradation correction can be calculated from the following equation (1). This equation can be derived by referring to FIG. 6: γ=(log Ymax−log Y)/(log Xmax−log X) (1) wherein Xmax is a maximum value of an input signal, Ymax is a maximum value of an output signal, X is an appropriate intermediate level of an input signal and Y is an appropriate intermediate level of an output signal. At Step 508, the image correction process is executed in accordance with the correction processing contents and parameters determined at Step 508. Next, with reference to the flow chart of FIG. 7, description will be made on a method of determining a face detection area in accordance with the focussing area information, as an example of the face detection area setup process at Step 504. At Step 701, the focussing area information is extracted from the accessory information acquired at Step 503 (refer to FIG. 5). In this embodiment, the focussing area information is “range finding frame number” and “used range finding frame”. At Step 702, range finding frame positions are obtained from the acquired “range finding frame number”, and a face detection area to be actually used for focussing control is determined from the “used range finding frame” to calculate coordinate values. For example, as shown in FIG. 8 three range finding frame positions are obtained from a “range finding frame number=3”, and a face detection area in an emphasized frame 801 is determined from a “used range finding frame=center” as prior to other frame. These three range finding positions can be obtained from the maker name and model name in the tag region 201, and it is preferable to store the range finding position information in the image processing apparatus for each pair of maker name and model name of DSC. Alternatively, the face detection area with a priority of order may be determined from the “used range finding frame” by roughly calculating the range finding positions by dividing image data in accordance with the “range finding frame number”. For example, as shown in FIG. 9 under the conditions of “range finding frame number=9” and “used range finding frame=center”, the image data area is divided in accordance with the range finding frame number (broken lines 901) and the face detection area (hatched area) 902 can be determined from the “used range finding frame” as an area with a priority of order. As to other range finding frames, for example, the range finding frame adjacent to the used range finding frame is selected as the face detection area with subsequent priority of order. Furthermore, as shown in FIG. 10, in order to obtain a face detection area having a size predetermined by the image processing apparatus 104, the size may be changed by adding or subtracting offset values 1002 to or from a range finding frame size 1001 at up, down, right and left. It is possible to flexibly deal with an image size during photographing, by determining a ratio of the face detection area to a resolution of photographed image data. A face detection start position 802, a lateral width 803 and a height 804 are calculated for the position of the face detection area determined by the above-described process. At Step 703, it is set so that the face detection-area calculated at Step 702 can be subjected to the face detection process. According to the embodiment, face detection can be performed efficiently by determining the face detection area in accordance with the focussing area information, by utilizing focussing control during photographing with DSC relative to a photographic subject having a high possibility of person. Efficient face detection can shorten the process time of the whole image correction process. Namely, according to this embodiment, face detection is performed by means for acquiring focussing area information in an image area by using image data and accessory information of the image data, means for determining a face detection area in the image area in accordance with the focussing area information, and means for executing a face detection process. Second Embodiment The second embodiment pertains to a method of setting a face detection area as described in the first embodiment, for the case that the focussing area information has a plurality of “used range finding frames”. The system configuration of the second embodiment is shown in FIG. 1 same as that of the first embodiment. In the second embodiment, the determination unit 110 of the face detection processing unit 109 shown in FIG. 1 determines a face detection area in accordance with the “range finding frame number” and “used range finding frames” of the first embodiment and in addition “photographic subject distance in each range finding frame”. It is therefore possible to deal with the case that there are a plurality of “used range finding frames”. With reference again to FIG. 7, description will be made on the face detection area setting method as the main characteristics of the second embodiment. In the second embodiment, at Step 701 information of the focussing area is acquired from the accessory information acquired at Step 503 shown in FIG. 5. The information of the focussing area includes “range finding frame number”, “used range finding frames” and “photographic subject distance in each range finding frame”. At Step 702, range finding frame positions are obtained from the “range finding frame number” of the acquired focussing area information. Areas to be actually used for focussing control are determined as face detection candidate areas, in accordance with the “used range finding frames”. According to the characteristics of the second embodiment, the face detection candidate areas are given a priority order in accordance with the “photographic subject distance in each range finding frame”. For example, as shown in FIG. 11, a range finding frame position 1301 is obtained from “range finding frame number=9”, and areas 1302 having an emphasized frame by “used range finding frames=left, center, right, upper right” are used as the face detection candidate areas. If the “photographic subject distance in each range finding frame” among the used range finding frames is “upper right<right <left<center”, the priority order of the face detection candidate areas is determined from the photographic subject distances. Namely, in this example, the upper right frame position having the shortest photographic subject distance is first designated as the face detection area. Thereafter, the flow advances to next Step. If the analysis completion (judgement that a person “exists” or analysis completion of the whole image) is not achieved at Step 506, then the face detection area at the “right” range finding frame position is used to advance to next Step. If the analysis completion is not achieved again at Step 506, a similar process is executed in the order of “left” and “center”. At Step 703, the face detection area information calculated at Step 702 is set so that it can be used in the face detection process. As described above, according to the second embodiment, face detection can be performed efficiently by determining the face detection area in accordance with the focussing area information, by utilizing the fact that there are a high possibility of focussing control during photographing with DSC relative to a photographic subject person and a high possibility that a person is at a position nearer than that of a landscape. Namely, according to the second embodiment, face detection is performed by means for acquiring focussing area information of an image by using image data and accessory information of the image data, means for acquiring photographic subject distance information from the focussing area information, means for determining a priority order of the focussing area information, and means for determining a face detection area in accordance with the priority order and executing a face detection process. Third Embodiment The third embodiment pertains to a method of setting a face detection area in accordance with photographic condition data other than the focussing area information. The system configuration of the third embodiment is shown in FIG. 1 same as that of the first embodiment. According to the configuration of the third embodiment, the photographic condition setup unit 102 of DSC 101 can set a photographic scene type as in the first embodiment and further set a detailed assistance mode. FIG. 12 shows an example of a display screen of the liquid crystal monitor 1501 mounted on the back of DSC 101. A photographer takes an image by using a guide display 1502 displayed on the liquid crystal monitor 1501. In the guide display 1502 of the third embodiment, auxiliary lines are displayed in order to confirm horizontal positions when persons in the right screen and a building or the like in a left background are to be photographed. FIG. 13 shows an image actually photographed. It can be seen that a user photographs by using the guide display 1502. Photographed image data is recorded in the format same as that of the first embodiment, and assistance mode information is recorded in the tag region 201 (refer to FIG. 2). The assistance mode information includes information of using the assistance mode and the type of the assistance mode. For example, in the assistance mode shown in FIGS. 12 and 13, a character string “left background” is recorded. In the image processing apparatus 104 of the third embodiment, the data analysis unit 106 has an accessory information acquirement unit 107 and a face detection processing unit 109 respectively different from those of the first embodiment. The accessory information acquirement unit 107 acquires the assistance mode information, instead of the focussing area information acquired by the first embodiment. The face detection processing unit 109 has a determination unit 110 different from that of the first embodiment. The determination unit 110 determines a face detection area in an image area in accordance with the assistance mode information contained in the accessory information. Next, with reference to the flow chart of FIG. 5, description will be made on the characteristic points of the operation of the image processing apparatus 104 of the third embodiment. At Step 503, the accessory information affixed during or after photographing is acquired from the image data read at Step 501. In this case, the assistance mode information is acquired, instead of the focussing area information acquired in the first and second embodiments. At Step 504, a face detection area is set in accordance with the assistance mode information in the accessory information acquired at Step 503. If the flow returns again to Step 504 because face detection was impossible at Steps 505 and 506, then a face detection area different from the already set face detection area is set again. Other Steps are similar to those of the first embodiment, and the description thereof is omitted. Next, with reference to the flow chart of FIG. 14, description will be made on a method of setting a face detection area at Step 504 which is the characteristics of the third embodiment. At Step 1801, information of the assistance mode is acquired from the accessory information acquired at Step 503 (refer to FIG. 5). At Step 1802, an area having a high possibility that the face of a person exists is determined as a face detection area, in accordance with the acquired assistance mode information. Thereafter, the coordinate values are calculated. For example, as shown in FIG. 15, a face detection area (hatched area) 1901 is determined from “assistance mode=left background”. The face detection area can be calculated from the maker name and model name stored in the tag region (refer to FIG. 2). It is preferable to store the assistance mode information of each maker of DSC and the face detection area corresponding to each assistance mode, in the image processing apparatus. In the third embodiment, although a rough position (hatched area) 1901 is determined as the face detection area, the face area of a person in the assistance display may be set more strictly as a first face detection area. At Step 1803, the face detection area information calculated at Step 1802 is set so that it can be used in the face detection process. As described above, according to the third embodiment, face detection can be performed efficiently by determining the face detection area in accordance with the position information of a person in the guide display, by utilizing the fact that there is a high possibility that the face of a person is photographed based on the guide display in the assistance mode. Namely, according to the third embodiment, face detection is performed by means for acquiring assistance mode information during photographing from image data and accessory information of the image data and means for determining a face detection area in accordance with the assistance mode information and executing a face detection process. Fourth Embodiment The fourth embodiment pertains to the case in which the information of a focussing area as in the first embodiment is represented by “coordinate values”. The system configuration of the fourth embodiment is shown in FIG. 1 same as that of the first embodiment. In the fourth embodiment, DSC 101 uses the “coordinate values” to represent the information of a focussing area which information is one of the photographic conditions. Namely, coordinate values (X, Y) are stored in TagNo.=4 (FIG. 2) of the accessory information as in the first embodiment, the coordinate values corresponding to the center of the area to be used for focussing control. As different from the first embodiment, the determination unit 110 of the face detection processing unit 109 in the data analysis unit 106 of the fourth embodiment determines a face detection area in accordance with the “coordinate values”. In the following, description will be made on a method of setting a face detection area according to the fourth embodiment. The image processing apparatus acquires the coordinate values of an area to be used for focussing control from the accessory information stored by DSC 101. Next, a square area is calculated having its center represented by the acquired coordinate values, and used as a face detection area. The square area is calculated so that it has the size predetermined by the image processing apparatus. Since the size is determined in proportion to a ratio of a photographed image to a resolution. It is therefore possible to flexibly deal with the image size during photographing. In place of the square area, it is possible to use a circle having a radius R about the acquired coordinate values, or a rectangle area such as the areas 801, 902 and 1001 shown in FIGS. 8 to 10. With the above-described process, a face detection are is set and a face detection process is executed. As described above, according to the fourth embodiment, the face detection process can be executed efficiently by determining a face detection area from the coordinate values, in the accessory information, of an area to be used for focussing control. The main aspects of the present invention are not limited only to detecting a face area. For example, the present invention is also applicable to detecting a characteristic area of an image of a photographic subject such as a specific object, animal or the like instead of the face of a person. By determining a characteristic detection area of an image in accordance with the accessory information of image data, it is possible to detect the characteristic area of an image in a short time and at high precision. This application claims priority from Japanese Patent Application No. 2004-018245 filed on Jan. 27, 2004, which is hereby incorporated by reference herein. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a means for extracting a photographic subject from still image data, and more particularly to a face detecting apparatus and method. 2. Related Background Art Digital still cameras and digital video cameras are prevailing rapidly nowadays. Along with this, there are increasing demands for tools such as a tool for processing images photographed with these photographing apparatuses to provide a high image quality. In the high image quality process, for example, a face detection process is executed for an image, and if there is a human face, a correction amount is determined basing upon the detected face. This method is widely known. Most of the process time required for the high image quality process is occupied by the face detection process time. This process time has been long desired to be shortened. Several means for improving a face detection efficiency have been proposed. For example, Japanese Patent Application Laid-Open No. 2003-163827 (no corresponding U.S. application) proposes an approach by which a photographing apparatus executes a pixel thinning process for a whole image in accordance with a photographing mode and a photographic subject magnification factor, and changes the number of divided blocks to be subjected to the face detection process. With this approach, a face detection precision is changed for each photographed image to improve the process efficiency. According to the invention described in Japanese Patent Application Laid-Open No. 2003-163827, the face detection process is executed for the whole area of an image. There arises therefore the problem that an area subjected to the face detection process increases greatly as the image data amount increases, and the process time prolongs. Another problem resides in that the detection precision is degraded if the number of thinned pixels is increased in order to shorten the process time. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention has been made in consideration of the above-described problems and aims to shorten the process time by executing the face detection process more efficiently, while the detection precision is maintained high. Especially, the present invention aims to executing the face detection process efficiently in the case of a portrait photographing with a plurality of faces. In order to achieve the above object, a face detecting apparatus of the present invention for extracting a face area of a photographic subject from an image on the basis of image data and accessory information associated with the image data comprises: means for determining a plurality of face detection area in an image area of the image in accordance with the accessory information; and means for executing a face detection process in the determined face detection area according to a prescribed priority of order. According to the present invention, since a face detection area is determined by using accessary information such as photographic conditions, a process time required to detect a face can be shortened. Furthermore, in a system for processing an image in accordance with a face detection result, the process time of the whole system can be shortened because of a shortened face detection process time. | 20050121 | 20100608 | 20050818 | 72751.0 | 0 | PARK, SOO JIN | FACE DETECTING APPARATUS AND METHOD | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,084 | ACCEPTED | Erroneous phase lock detection circuit | The present invention is concerned with a phase comparator circuit and provides an erroneous phase lock detection circuit that detects erroneous phase lock occurring when the duty cycle of data deviates from 100% in a comparison of a phase difference between the data and a clock. The erroneous phase lock detection circuit incorporated in a phase comparator that detects a phase difference between data and a clock comprises: a first phase detection unit that detects a phase difference by measuring a difference between the leading edge of the data and the phase of the clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference by measuring a difference between the trailing edge of the data and the phase of the clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies erroneous phase lock. | 1. An erroneous phase lock detection circuit incorporated in a phase comparator that detects a phase difference between data and a clock, comprising: a first phase detection unit that detects a phase difference by measuring a difference between the leading edge of the data and the phase of the clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference by measuring a difference between the trailing edge of the data and the phase of the clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies an erroneous phase lock. 2. The erroneous phase lock detection circuit according to claim 1, further comprising a control unit that controls or reverses a clock to be transferred to the phase comparator, wherein when the erroneous phase lock verification unit verifies erroneous phase lock, the control unit reverses the clock. 3. The erroneous phase lock detection circuit according to claim 1, further comprising a control unit that controls a control voltage with which the output frequency of a voltage-controlled oscillator (VCO) that generates a clock to be transferred to the phase comparator is changed, wherein when the erroneous phase lock verification unit verifies erroneous phase lock, the control unit changes the control voltage so that the phase of the clock will lock onto a normal phase. 4. The erroneous phase lock detection circuit according to claim 1, further comprising a control unit that controls a control voltage with which the output frequency of a voltage-controlled oscillator (VCO) that generates a clock to be transferred to the phase comparator is changed, wherein: the control unit comprises a memory that monitors a control voltage level during a period during which the data has a normal phase and records the control voltage level, and a control voltage generation block that generates a control voltage, of which level is changed from the recorded control voltage level by a predetermined voltage, so that the phase of the clock locking onto an erroneous phase will lock onto a normal phase; and when the erroneous phase lock verification unit verifies erroneous phase lock, monitoring performed by the memory is suspended and the control voltage produced by the control voltage generation block is transferred to the VCO. 5. An erroneous phase lock detection circuit incorporated in a phase comparator that detects a phase difference between data and a clock, and that comprises a first frequency divider which produces at the leading edge of the data an output whose frequency is a half of the frequency of the data, a second frequency divider which produces at the trailing edge of the data an output whose frequency is a half of the frequency of the data, and a clock generator that generates a half-cycle clock by halving the frequency of the clock, the erroneous phase lock detection circuit comprising: a first phase detection unit that detects a phase difference between data sent from the first frequency divider and the half-cycle clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference between data sent from the second frequency divider and the half-cycle clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies erroneous phase lock. | CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation application and is based upon PCT/JP02/12977, filed on Dec. 11, 2002. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase comparison circuit or, more particularly, to a circuit for detecting erroneous phase lock occurring when the duty cycle of data deviates from 100% during comparison of the data with a clock during which a phase difference between the data and clock is detected. 2. Description of the Related Art At a receiving terminal station of an optical transmission system, synchronous reproduction is performed in order to convert a data wave, which is distorted due to the characteristic of an optical transmission line or convolution of noise, into an original fine digital signal. In general, a phase-locked loop (PLL) is used to generate a clock whose frequency is synchronous with the repetition frequency of received data. The clock is used to identify received data and the data is reproduced. For example, when a non-return-to-zero (NRZ) signal to be transmitted at a bit rate of several tens of gigabits per second is adopted as a signal carrying data, the bit time is as short as several tens of picoseconds. If the signal is affected with the foregoing distortion or noise, the time during which data can be identified is very short. The phase of a clock produced by the PLL must lock onto the phase of received data with an optimal relationship maintained between the phases. FIG. 1 shows a Hogge-type phase comparator generally employed in a PLL. FIG. 2 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 100% is adopted as a data-carrying signal. In FIG. 2, signals (a) to (h) are signals developed at nodes (a) to (h) in FIG. 1. The duty cycle is the ratio (t/T) 100 (%) of a pulse duration t during which data or a bit “1” persists to an interval T between pulses or bits, wherein a bit rate is expressed as f=1/T. The Hogge-type phase comparator comprises two D flip-flops 1 and 2, two exclusive OR circuits 3 and 4, and two analog rectification circuits (filters) 5 and 6. The D flip-flop 1 and exclusive OR circuit 3 detect (produce a signal e) a period φ from the change in input data (the leading or trailing edge of input data) to the leading edge of a clock. On the other hand, the D flip-flop 2 and exclusive OR circuit 4 detect (produce a signal f) a period π from the change in the output of the D flip-flop 1 (the leading or trailing edge) to the trailing edge of the clock. The period φ provided by the exclusive OR circuit 3 varies depending on the temporal relationship between the change in the input data and the leading edge of the clock. The period π provided by the exclusive OR circuit 4 is always half the cycle of the clock. Moreover, the number of outputs φ of the exclusive OR circuit 3 is always equal to the number of outputs π of the exclusive OR circuit 4. Consequently, when the leading edge of the clock is in the center of input data, the period φ provided by the exclusive OR circuit 3 and the period π provided by the exclusive OR circuit 4 are equal to each other and are half the cycle of the clock. Assume that the output φ of the exclusive OR circuit 3 and the output π of the exclusive OR circuit 4 are rectified by the respective filters 5 and 6 in order to produce rectified signals g and h respectively. When the rectified signal h of the output π of the exclusive OR circuit 4 is used as a reference, the rectified signal g of the output φ of the exclusive OR circuit 3 is regarded as a sawtooth wave whose level varies by the half cycle of the clock in both directions with the reference level as a center (see FIG. 2). A time point at which the rectified outputs cross, that is, a time point at which the leading edge of the clock comes in the center of input data is regarded as an optimal time point of identification. The output frequency of a voltage-controlled oscillator (VCO) included in the PLL is controlled so that the rectified outputs will be equal to each other (g=h), whereby the leading edge of the clock stably coincides with at the optimal time point of identification within the cycle of input data. FIG. 3 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a data-carrying signal. In FIG. 3, signals (a) to (h) are signals developed at the nodes (a) to (h) in FIG. 1. When the duty cycle of data deviates from 100%, the output of the PLL may lock onto a phase different from the phase onto which the output should lock. As mentioned previously, when the duty cycle of data is 100%, the data wave has only one slope in one direction within one cycle (0 to 2π) and an average signal level attained during the time equivalent to one slope is detected at the same phase over all the cycles. However, when the duty cycle deviates from 100%, the wave has two slopes in the same direction within one cycle and the average signal levels attained during the times equivalent to the two slopes are the same as each other and detected in two phases of a normal phase and an erroneous phase. When the duty cycle of data is 75%, as long as a phase difference of the data from a clock is limited, the average signal level varies in the same manner as it does when the duty cycle if 100%. However, if the phase difference of the data from the clock exceeds 1.5π (75%), the edge of the clock comes after the trailing edge of the data. Therefore, a clock pulse produced when the phase difference is equal to or smaller than 1.5π may not be produced. In this case, a sawtooth wave exhibits two phases within one cycle (2π) (g and h), that is, exhibits a normal phase and an erroneous phase in which the wave assumes the same average signal level as it does in the normal phase. Consequently, conventionally, if the erroneous phase locks onto the phase of a clock, the time during which data is identified becomes very short or it becomes impossible to reproduce data. Referring to FIG. 3, a description has been made of a case where the duty cycle of data decreases from 100%. Even when the duty cycle becomes equal to or larger than 100% or, for example, 125%, a sawtooth wave exhibits two phases within one cycle thereof (2π) and has two slopes in the same direction. Patent Documents relevant to the foregoing related art include Japanese Unexamined Patent Application Publication No. 2000-183731 (see FIG. 35 to FIG. 38) and Japanese Patent No. 3094971 (see FIG. 1 to FIG. 3). SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an erroneous phase lock detection circuit that is incorporated in a phase comparator circuit included in a PLL and that detects erroneous phase lock occurring when the duty cycle of data deviates from 100%. Another object of the present invention is to provide an erroneous phase lock detection circuit including a facility that, when erroneous phase lock is detected, extends control so as to detect a normal phase. According to the present invention, an erroneous phase lock detection circuit incorporated in a phase comparator that detects a phase difference between data and a clock comprises: a first phase detection unit that detects a phase difference by measuring a difference between the leading edge of the data and the phase of the clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference by measuring a difference between the trailing edge of the data and the phase of the clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies an erroneous phase lock. According to the present invention, a phase comparator that detects a phase difference between data and a clock comprises: a first frequency divider that provides an output, of which frequency is a half of the frequency of data, at the leading edge of the data; a second frequency divider that provides an output, of which frequency is a half of the frequency of the data, at the trailing edge of the data; and a clock generator that generates a half-cycle clock by halving the frequency of the clock. An erroneous phase lock detection circuit incorporated in the phase comparator comprises: a first phase detection unit that detects a phase difference between the data sent from the first frequency divider and the half-cycle clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference between the data sent from the second frequency divider and the half-cycle clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies an erroneous phase lock. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a Hogge-type phase comparator; FIG. 2 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 100% is adopted as a signal carrying data transferred to the comparator shown in FIG. 1; FIG. 3 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a signal carrying data transferred to the comparator shown in FIG. 1; FIG. 4 shows the principles and configuration of a Hogge-type phase comparator including an erroneous phase lock detection circuit in accordance with the present invention; FIG. 5 shows an embodiment of the present invention; FIG. 6 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a signal carrying data transferred to the embodiment shown in FIG. 5; FIG. 7 shows the waveforms of signals observed when an NRZ signal exhibiting a duty cycle of 90% is adopted as a signal carrying data transferred to the embodiment shown in FIG. 5; FIG. 8 shows the waveforms of signals observed when an NRZ signal having a duty cycle of 100% is adopted as a signal carrying data transferred to the embodiment shown in FIG. 5; FIG. 9 shows the waveforms of signals observed when an NRZ signal having a duty cycle of 125% is adopted as a signal carrying data transferred to the embodiment shown in FIG. 5; FIG. 10 shows an example of the circuitry of a difference detector; FIG. 11 shows the first example of a phase control circuit; FIG. 12 shows the second example of a phase control circuit; FIG. 13 shows the third example of a phase control circuit; FIG. 14 shows an embodiment of the present invention employing a half-cycle clock; FIG. 15 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a signal carrying data transferred to the embodiment shown in FIG. 14; and FIG. 16 shows an example of a phase control circuit included in the embodiment shown in FIG. 14. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 shows the principles and configuration of a Hogge-type phase comparator in which an erroneous phase lock detection circuit, in accordance with the present invention, is incorporated. Referring to FIG. 4, D flip-flops 1 and 2 are identical to those shown in FIG. 1. A leading/trailing phase detector 7 is one functional block into which the exclusive OR circuit 4 and the filter 6 shown in FIG. 1 are integrated. The exclusive OR circuit 3 and the filter 5 shown in FIG. 1 are designed to detect both the leading and trailing edges of input data. In contrast, an erroneous phase lock detection circuit 10 in accordance with the present invention comprises a leading phase detector 11 that detects only the leading edge of input data and a trailing phase detector 12 that detects only the trailing edge thereof. When only the leading edge of input data is discussed, the repetition frequency of the leading edge agrees with a bit rate f(1/T). The input data is therefore regarded as data having a duty cycle of 100%. Likewise, when only the trailing edge of the input data is discussed, the repetition frequency of the trailing edge agrees with the bit rate f(1/T). The input data can be regarded as data having the duty cycle of 100%. Consequently, the outputs of the leading phase detector 11 and trailing phase detector 12 are sawtooth waves that, similarly to the one described in conjunction with FIG. 2 and provided when input data has a duty cycle of 100%, have slopes in the same direction within one cycle (2π). In this case, the deviation of the duty cycle of the input data from the duty cycle of 100% is manifested as a phase difference between the signals representing the leading or trailing phase of the input data. A subtractor 13 calculates a difference between the phases detected by the leading phase detector 11 and trailing phase detector 12 respectively. When the phase difference exceeds a predetermined threshold, a window comparator 15 verifies erroneous phase lock. For example, assuming that the duty cycle of input data is 75%, when the phase difference between data and a clock attained within one cycle (2π) ranges from 1.5π to 2π, the phase difference will expand. The window comparator 15 determines a threshold so that the expanded phase difference alone will be detected and, thus, detects a state of erroneous phase lock. On the other hand, an adder 14 calculates the sum of the phases detected by the leading phase detector 11 and trailing phase detector 12 respectively. The adder 14 works equivalently to the exclusive OR circuit 3 and filter 5 that are included in the conventional comparator shown in FIG. 1 for detecting both the leading and trailing edges of input data. The output of the adder 14 exhibits the same phase characteristic as those of an output g (FIG. 2) provided when the duty cycle of input data is 100% and of an output g (FIG. 3) provided when the duty cycle thereof is 75%. Consequently, an output of a comparator 8 resulting from comparison of phases represents either of two states of a normal phase and an erroneous phase. When the output represents the erroneous phase on a stable basis, the erroneous phase lock detection circuit 10 transmits an output signifying that erroneous phase lock is detected. According to the present invention, the output signifying that erroneous phase lock is detected is used to change a phase, onto which a clock is locking, into a normal phase. FIG. 5 to FIG. 9 show an embodiment of the present invention. FIG. 5 shows a concrete example of circuitry shown in FIG. 4. FIG. 6 to FIG. 9 are timing charts showing the waveforms of signals observed when NRZ signals having different duty cycles are employed. To begin with, a description will be made of the circuitry shown in FIG. 5 and the timing chart of FIG. 6 showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is employed. Referring to FIG. 5, the circuitry of a phase comparator 20 defined with a dot-dash line is identical to that shown in FIG. 1. However, the exclusive OR circuit 3 in FIG. 1 is replaced with gate circuits 21 to 24 and an adder 14 in order to implement the present invention. The gate circuits 21 to 24 and adder 14 perform a logical exclusive OR operation. For example, when an input of a D flip-flop 1 is 0 and the output thereof is 0, the logical input shall be (0,0). At this time, the adder 14 provides an output of 0. Likewise, when the logical input is (1,0) or (0,1), the output is 1. When the logical input is (1,1), the output is 0. These operations are logical operations performed by the exclusive OR circuit 3. An output e1 of an AND circuit 22 becomes 1 only when the input of the D flip-flop 1 is 1 and the output thereof is 0. Consequently, the output e1 of the AND circuit 22 persists during a period from the leading edge of input data to the leading edge of a clock. On the other hand, an output e2 of an AND circuit 24 becomes 1 only when the input of the D flip-flop 1 is 0 and the output thereof is 1. Consequently, the output e2 of the AND circuit 24 persists during a period from the trailing edge of the input data to the leading edge of the clock. A filter 25 rectifies a leading phase signal sent from the AND circuit 22 and transmits the resultant signal i1. Independently of the filter 25, a filter 26 rectifies a trailing phase signal sent from the AND circuit 24 and transmits the resultant signal i2. Referring to FIG. 6, the rectified outputs i1 and i2 are sawtooth waves having slopes in the same direction within one cycle (2π). The deviation of the duty cycle of the input data from the duty cycle 100% is manifested as a phase difference of ¼π(=2π−{fraction (3/2)}π) between the rectified outputs. Moreover, when the outputs of the AND circuits 22 and 24 are summated by the adder 14 and rectified by the filter 5, the resultant output is equivalent to the output g provided via the exclusive OR circuit 3 and filter 5 included in the conventional phase comparator. A difference detector serving as a subtractor 13 detects a difference j between the rectified outputs. A window comparator 15 comprises two comparators 27 and 28, and detects an output which exceeds a difference between thresholds ref1 and ref2, as an erroneous-phase signal 1. In this example, the window comparator 15 detects as an erroneous-phase stage a stage from a phase {fraction (3/2)}π to a phase 2π within one cycle (2π), within which the phase difference j expands, and transmits the erroneous-phase signal 1 representing the erroneous-phase stage. FIG. 7 shows an example of the waveforms of signals observed when an NRZ signal having a duty cycle of 90% is adopted. FIG. 8 shows an example of the waveforms of signals observed when an NRZ signal having a duty cycle of 100% is adopted. FIG. 9 shows an example of the waveforms of signals observed when an NRZ signal having a duty cycle of 125% is adopted. As is apparent from these drawings, whatever of the duty cycle an input signal has, outputs i1 and i2 produced by rectifying signals that represent the leading phase or trailing phase of the input data are sawtooth waves having slopes in the same direction within one cycle (2π). Referring to FIG. 8 that shows waveforms observed when the duty cycle of input data is 100%, a phase difference between signals representing the leading or trailing phase of the input data is zero, and an output g produced by summating the signals is also a sawtooth wave having a slope in the same direction as the signals do within one cycle. On the other hand, as shown in FIG. 6, FIG. 7, and FIG. 9, when the duty cycle of input data deviates from 100%, the sawtooth wave has two phases within one cycle according to the phase difference between the signals. The stage of the sawtooth wave having the second phase is detected as an erroneous-phase stage. FIG. 10 shows an example of the circuitries of the filters 25 and 26 and the difference detector 13. Referring to FIG. 10, the difference detector 13 comprises FETs 32 and 33 constituting a charge pump and current sources 31 and 34. In this example, the outputs e1 and e2 of the AND circuits 22 and 24 are directly applied to the gates of the FETs 32 and 33 but not transferred to the filters 25 and 26 shown in FIG. 5. When the FET 32 is set to an on state with a leading phase signal e1, a capacitor 35 in an output stage is charged by the current source 31. On the other hand, when the FET 33 is set to the on state with a trailing phase signal e2, the capacitor in the output stage is discharged by the current source 34. A different output produced by repeating the charge and discharge is transferred to the window comparator 15. In this case, the necessity of the filters 25 and 26 shown in FIG. 5 is obviated owing to the rectification achieved through the charge and discharge. A floating capacitor whose capacitance is several picofarads is adopted as the capacitor 35 drawn with dashed lines. The capacitance of several picofarads is large enough to transmit data at a bit rate at the gigabit level. FIG. 11 to FIG. 13 show phase control circuits that, when erroneous phase lock is detected, extends control so as to lock a normal phase onto the phase of a clock. Part (a) of FIG. 11 is a block diagram showing a first phase control circuit, and part (b) of FIG. 11 is a flowchart describing a control sequence followed by the first phase control circuit. A phase comparator 20 and an erroneous phase lock detection circuit 10 are identical to those shown in FIG. 5. A voltage-controlled oscillator (VCO) varies an output frequency thereof according to a compared signal g sent from the phase comparator 20 so as to control, that is, advance or delay the phase of a clock referenced by the phase comparator 20. In this example, when the erroneous phase lock detection circuit 10 detects erroneous phase lock (S10 and S11), a selector 41 is controlled in order to reverse a clock that is transferred to the phase comparator 20 (changing the phase π (S12). Consequently, the phase comparator 20 detects a normal phase. Part (a) of FIG. 12 is a block diagram showing a second phase control circuit, and part (b) of FIG. 12 is a flowchart describing a control sequence followed by the second phase control circuit. The phase comparator 20, erroneous phase lock detection circuit 10, and voltage-controlled oscillator (VCO) are identical to those shown in FIG. 11. In this case, when the erroneous phase lock detection circuit 10 detects erroneous phase lock (S20 and S21), a switch 43 is turned on in order to forcibly step up or down (g±α) a control voltage, which is used to change the output frequency of the VCO 42, by a predetermined voltage α (S22). Consequently, a clock is unlocked from an erroneous phase, and the phase comparator 20 detects a normal phase. Part (a) of FIG. 13 is a block diagram showing a third phase control circuit, and part (b) of FIG. 13 is a flowchart describing a control sequence followed by the third phase control circuit. The phase comparator 20, erroneous phase lock detection circuit 10, and voltage-controlled oscillator (VCO) are identical to those shown in FIG. 11. In this example, a memory 45 periodically monitors a phase-compared signal g, records the voltage level of the signal g exhibiting a normal phase, and updates the recorded signal level. Moreover, a microscopic voltage level (g±α) is calculated by shifting the recorded voltage level by a predetermined voltage and recorded in order to lock the phase of a clock, which is locking onto an erroneous phase, onto a normal phase. A microscopic voltage generator 46 generates the microscopic voltage according to the voltage level sent from the memory. When the erroneous phase lock detection circuit 10 detects erroneous phase lock (S30 and S31), a selector 44 is controlled in order to select the microscopic voltage generator 46. At the same time, the memory is instructed to suspend monitoring (S32 and S33). Consequently, a clock locking onto the erroneous phase is unlocked, and the phase comparator 20 detects a normal phase. In this example, compared with the examples shown in FIG. 11 and FIG. 12, high-precision control can be extended quickly. FIG. 14 and FIG. 15 show another embodiment of the present invention. FIG. 14 shows the circuitry of a phase comparator of a Hogge-type that uses a half-cycle clock according to the present invention. FIG. 15 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a data-carrying signal. Referring to FIG. 14, halving frequency dividers 51 and 52 are realized with, for example, T flip-flops. In this case, the halving frequency divider 51 reverses its output at the leading edge of input data, and the halving frequency divider 52 reverses its output at the trailing edge of the input data. Consequently, the halving frequency dividers 51 and 52 provide signals a1 and a2, of which frequencies are a half of the frequency of the input data, at the leading or trailing edge of the input data. Hereinafter, the actions of the halving frequency divider 51 alone will be described. The actions of the halving frequency divider 52 are identical to those of the half frequency divider 51. A half-frequency signal a1 synchronous with the leading edge of input data and a normal half-cycle clock b=½f0 are transferred to a D flip-flop 53. A reverse half-cycle clock is transferred to the other D flip-flop 54. Herein, the half-cycle clock allowing devices to act leisurely is adopted in order to permit transmission at a bit rate of the gigabit level. An AND of the outputs of the D flip-flops 53 and 54 is a signal m1 equivalent to a component of a half-frequency signal measured from the leading edge of the half-cycle clock to the trailing edge thereof. An AND of a reverse of the signal m1 and a half-frequency signal a1 is a phase signal e1 whose bit time is equivalent to 2π+φ and which is synchronous with the leading edge of input data a. Likewise, the halving frequency divider 52 provides a phase signal e2 whose bit time is equivalent to 2π+φ+d. Herein, φ denotes a phase difference detected by measuring a difference from the leading edge of the input data to the leading edge of the half-cycle clock. Moreover, d denotes a phase deviation from a phase of data having a duty cycle of 100%. In this example, the half-frequency signal a1 is synchronous with the leading edge of input data a, and the half-frequency signal a2 is synchronous with the trailing edge of the input data a. The half-frequency signals can be regarded as data items having a duty cycle of 100%. Consequently, rectified outputs produced by rectifying the phase signals e1 and e2 are, as shown in FIG. 15, sawtooth waves i1 and i2 having slopes in the same direction within one cycle. Subsequent erroneous phase lock detection is identical to the aforesaid one. As mentioned above, an erroneous phase lock detection circuit in accordance with the present invention can be adapted to a Hogge type phase comparator employing a half-cycle clock. FIG. 16 shows an example of a phase control circuit employed when a half-cycle clock is adopted, part (a) of FIG. 16 is a block diagram thereof, and part (b) of FIG. 16 is a flowchart describing an example of a control sequence to be followed by the phase control circuit. The phase control circuit in this example has the same configuration as that shown in the block diagram of FIG. 11. Herein, a phase comparator 49 and an erroneous phase lock detection circuit 50 which are designed to use a half-cycle clock and shown in FIG. 14 are employed, and a 90° delay circuit 47 is substituted for an inverter. When the erroneous phase lock detection circuit 50 detects erroneous phase lock (S40 and S41), a selector 48 is controlled in order to 90° delay a clock to be transferred to the phase comparator 20 (S42). Consequently, the phase comparator 49 detects a normal phase. As described so far, according to the present invention, there is provided an erroneous phase lock detection circuit that detects an erroneous phase lock occurring when the duty cycle of data deviates from 100% and that is incorporated in a phase comparator circuit included in a PLL. When erroneous phase lock is detected, control is extended in order to detect a normal phase. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a phase comparison circuit or, more particularly, to a circuit for detecting erroneous phase lock occurring when the duty cycle of data deviates from 100% during comparison of the data with a clock during which a phase difference between the data and clock is detected. 2. Description of the Related Art At a receiving terminal station of an optical transmission system, synchronous reproduction is performed in order to convert a data wave, which is distorted due to the characteristic of an optical transmission line or convolution of noise, into an original fine digital signal. In general, a phase-locked loop (PLL) is used to generate a clock whose frequency is synchronous with the repetition frequency of received data. The clock is used to identify received data and the data is reproduced. For example, when a non-return-to-zero (NRZ) signal to be transmitted at a bit rate of several tens of gigabits per second is adopted as a signal carrying data, the bit time is as short as several tens of picoseconds. If the signal is affected with the foregoing distortion or noise, the time during which data can be identified is very short. The phase of a clock produced by the PLL must lock onto the phase of received data with an optimal relationship maintained between the phases. FIG. 1 shows a Hogge-type phase comparator generally employed in a PLL. FIG. 2 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 100% is adopted as a data-carrying signal. In FIG. 2 , signals (a) to (h) are signals developed at nodes (a) to (h) in FIG. 1 . The duty cycle is the ratio (t/T) 100 (%) of a pulse duration t during which data or a bit “1” persists to an interval T between pulses or bits, wherein a bit rate is expressed as f=1/T. The Hogge-type phase comparator comprises two D flip-flops 1 and 2 , two exclusive OR circuits 3 and 4 , and two analog rectification circuits (filters) 5 and 6 . The D flip-flop 1 and exclusive OR circuit 3 detect (produce a signal e) a period φ from the change in input data (the leading or trailing edge of input data) to the leading edge of a clock. On the other hand, the D flip-flop 2 and exclusive OR circuit 4 detect (produce a signal f) a period π from the change in the output of the D flip-flop 1 (the leading or trailing edge) to the trailing edge of the clock. The period φ provided by the exclusive OR circuit 3 varies depending on the temporal relationship between the change in the input data and the leading edge of the clock. The period π provided by the exclusive OR circuit 4 is always half the cycle of the clock. Moreover, the number of outputs φ of the exclusive OR circuit 3 is always equal to the number of outputs π of the exclusive OR circuit 4 . Consequently, when the leading edge of the clock is in the center of input data, the period φ provided by the exclusive OR circuit 3 and the period π provided by the exclusive OR circuit 4 are equal to each other and are half the cycle of the clock. Assume that the output φ of the exclusive OR circuit 3 and the output π of the exclusive OR circuit 4 are rectified by the respective filters 5 and 6 in order to produce rectified signals g and h respectively. When the rectified signal h of the output π of the exclusive OR circuit 4 is used as a reference, the rectified signal g of the output φ of the exclusive OR circuit 3 is regarded as a sawtooth wave whose level varies by the half cycle of the clock in both directions with the reference level as a center (see FIG. 2 ). A time point at which the rectified outputs cross, that is, a time point at which the leading edge of the clock comes in the center of input data is regarded as an optimal time point of identification. The output frequency of a voltage-controlled oscillator (VCO) included in the PLL is controlled so that the rectified outputs will be equal to each other (g=h), whereby the leading edge of the clock stably coincides with at the optimal time point of identification within the cycle of input data. FIG. 3 is a timing chart showing the waveforms of signals observed when an NRZ signal having a duty cycle of 75% is adopted as a data-carrying signal. In FIG. 3 , signals (a) to (h) are signals developed at the nodes (a) to (h) in FIG. 1 . When the duty cycle of data deviates from 100%, the output of the PLL may lock onto a phase different from the phase onto which the output should lock. As mentioned previously, when the duty cycle of data is 100%, the data wave has only one slope in one direction within one cycle (0 to 2π) and an average signal level attained during the time equivalent to one slope is detected at the same phase over all the cycles. However, when the duty cycle deviates from 100%, the wave has two slopes in the same direction within one cycle and the average signal levels attained during the times equivalent to the two slopes are the same as each other and detected in two phases of a normal phase and an erroneous phase. When the duty cycle of data is 75%, as long as a phase difference of the data from a clock is limited, the average signal level varies in the same manner as it does when the duty cycle if 100%. However, if the phase difference of the data from the clock exceeds 1.5π (75%), the edge of the clock comes after the trailing edge of the data. Therefore, a clock pulse produced when the phase difference is equal to or smaller than 1.5π may not be produced. In this case, a sawtooth wave exhibits two phases within one cycle (2π) (g and h), that is, exhibits a normal phase and an erroneous phase in which the wave assumes the same average signal level as it does in the normal phase. Consequently, conventionally, if the erroneous phase locks onto the phase of a clock, the time during which data is identified becomes very short or it becomes impossible to reproduce data. Referring to FIG. 3 , a description has been made of a case where the duty cycle of data decreases from 100%. Even when the duty cycle becomes equal to or larger than 100% or, for example, 125%, a sawtooth wave exhibits two phases within one cycle thereof (2π) and has two slopes in the same direction. Patent Documents relevant to the foregoing related art include Japanese Unexamined Patent Application Publication No. 2000-183731 (see FIG. 35 to FIG. 38 ) and Japanese Patent No. 3094971 (see FIG. 1 to FIG. 3 ). | <SOH> SUMMARY OF THE INVENTION <EOH>Accordingly, an object of the present invention is to provide an erroneous phase lock detection circuit that is incorporated in a phase comparator circuit included in a PLL and that detects erroneous phase lock occurring when the duty cycle of data deviates from 100%. Another object of the present invention is to provide an erroneous phase lock detection circuit including a facility that, when erroneous phase lock is detected, extends control so as to detect a normal phase. According to the present invention, an erroneous phase lock detection circuit incorporated in a phase comparator that detects a phase difference between data and a clock comprises: a first phase detection unit that detects a phase difference by measuring a difference between the leading edge of the data and the phase of the clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference by measuring a difference between the trailing edge of the data and the phase of the clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies an erroneous phase lock. According to the present invention, a phase comparator that detects a phase difference between data and a clock comprises: a first frequency divider that provides an output, of which frequency is a half of the frequency of data, at the leading edge of the data; a second frequency divider that provides an output, of which frequency is a half of the frequency of the data, at the trailing edge of the data; and a clock generator that generates a half-cycle clock by halving the frequency of the clock. An erroneous phase lock detection circuit incorporated in the phase comparator comprises: a first phase detection unit that detects a phase difference between the data sent from the first frequency divider and the half-cycle clock and transmits an average of phase differences; a second phase detection unit that detects a phase difference between the data sent from the second frequency divider and the half-cycle clock and transmits an average of phase differences; and an erroneous phase lock verification unit that, when the difference between the average phase difference sent from the first phase detection unit and the average phase difference sent from the second phase detection unit exceeds a predetermined range, verifies an erroneous phase lock. | 20050121 | 20080708 | 20050609 | 71555.0 | 0 | GHEBRETINSAE, TEMESGHEN | ERRONEOUS PHASE LOCK DETECTION CIRCUIT | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,113 | ACCEPTED | Backup system, backup controlling apparatus, backup data managing method and a computer readable recording medium recorded thereon backup controlling program | A backup system which can diminish a danger that backup data of a storage of a computer to be backed up sustains a damage due to disaster, an accident or the like, and restore the storage easily and within a short time when the storage up is damaged or lost due to disaster, an accident or the like. The system can be configured with a small facility investment. The system comprises a plurality of backup data storages, an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located as an archiving place among the plural backup data storages on the basis of the area in which the storage is located, and a backup processing unit for storing the backup data in the backup data storage determined as the archiving place by the archiving place determining unit. | 1. A backup system comprising: a plurality of backup data storages located in areas differing from one another to archive data in a storage provided to an information processing apparatus as backup data; an archiving place determining unit for selectively determining a backup data storage physically away from an area in which said storage is located among said plural backup data storages as an archiving place on the basis of said area in which said storage is located; and a backup processing unit for storing said backup data in said backup data storage determined as said archiving place by said archiving place determining unit. 2. The backup system according to claim 1 further comprising: information for reference configured by beforehand relating information for specifying said information processing apparatus or information for specifying a user of said information processing apparatus to said backup data storage physically away from said area in which said storage provided to said information processing apparatus is located; said archiving place determining unit referring to said information for reference on the basis of said information for specifying said information processing apparatus or said information for specifying a user of said information processing apparatus, and selectively determining said backup data storage as said archiving place among said plural backup data storages. 3. The backup system according to claim 1 further comprising: an area determining unit communicably connected to said information processing apparatus over a communication line, and determining an area in which said storage is located; said archiving place determining unit selectively determining, on the basis of said area in which said storage is located determined by said area determining unit, said backup data storage physically away from said area in which said storage is located as said archiving place among said plural backup data storages. 4. The backup system according to claim 1 further comprising: a degree-of-importance designating unit for designating a degree of importance of data in said storage; said archiving place determining unit preferentially determining a backup data storage physically farther from said area in which said storage is located as said degree of importance is higher among said plural backup data storages according to said degree of importance designated by said degree-of-importance designating unit. 5. The backup system according to claim 1 further comprising: an archiving place designation inputting unit being able to selectively designate a specific backup data storage among said plural backup data storages; said archiving place determining unit selectively determining said backup data storage designated by said archiving place designation inputting unit as said archiving place. 6. A backup controlling apparatus for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprising: an archiving place determining unit for selectively determining a backup data storage physically away from an area in which said storage is located as an archiving place among said plural backup data storages on the basis of said area in which said storage is located. 7. The backup controlling apparatus according to claim 6 further comprising: information for reference configured by relating information for specifying said information processing apparatus or information for specifying a user of said information processing apparatus to said backup data storage physically away from said area in which said storage provided to said information processing apparatus is located; said archiving place determining unit referring to said information for reference on the basis of said information for specifying said information processing apparatus or said information for specifying a user of said information processing apparatus, and selectively determining said backup data storage as said archiving place among said plural backup data storages. 8. The backup controlling apparatus according to claim 6 further comprising: an area determining unit communicably connected to said information processing apparatus over a communication line, and determining said area in which said storage is located; said archiving place determining unit selectively determining, on the basis of said area in which said storage is located determined by said area determining unit, said backup data storage physically away from said area in which said storage is located as said archiving place among said plural backup data storages. 9. The backup controlling apparatus according to claim 6, wherein said archiving place determining unit preferentially determining a backup data storage unit physically farther from said area in which said storage is located as a degree of importance of data in said storage is higher as said archiving place among said plural backup data storages according to the degree of importance of data in said storage. 10. The backup controlling apparatus according to claim 6, wherein information about said backup data is related as attribute information to said backup data, and recorded. 11. The backup controlling apparatus according to claim 6 further comprising: a restoration processing unit for restoring said backup data stored in said backup data storage onto an arbitrary storage. 12. A backup data managing method for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprising: an archiving place determining step of selectively determining a backup data storage physically away from an area in which said storage is located among said plural backup data storages as an archiving place on the basis of said area in which said storage is located; and a backup processing step of storing said backup data in said backup data storage determined as said archiving place at said archiving place determining step. 13. The backup data managing method according to claim 12 further comprising: an information-for-reference preparing step of preparing information for reference configured by relating information for specifying said information processing apparatus or information for specifying a user of said information processing apparatus to said backup data storage physically away from said area in which said storage provided to said information processing apparatus is located; at said archiving place determining step, said information for reference being referred on the basis of said information for specifying said information processing apparatus or said information for specifying a user of said information processing apparatus to selectively determine said backup data storage as said archiving place among said plural backup data storages. 14. The backup data managing method according to claim 12 further comprising: an area determining step of determining said area in which said storage is located; at said archiving place determining step, on the basis of said area in which said storage is located determined at said area determining step, said backup data storage physically away from said area in which said storage is located being selectively determined as said archiving place among said plural backup data storages. 15. The backup data managing method according to claim 12 further comprising: a degree-of-importance designating step of designating a degree of importance of data in said storage; at said archiving place determining step, a backup data storage physically farther from said area in which said storage is located being determined as said archiving place as said degree of importance is higher among said plural backup data storages according to said degree of importance designated at said degree-of-importance designating step. 16. The backup data managing method according to claim 12 further comprising: an archiving place designation inputting step at which a specific backup data storage can be selectively designated among said plural backup data storages; at said archiving place determining step, said backup data storage designated at said archiving place designation inputting step being selectively determined as said archiving place. 17. A computer readable recording medium recorded thereon a backup controlling program for making a computer execute a backup controlling function of archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another; said backup controlling program making said computer function as an archiving place determining unit for selectively determining a backup data storage physically away from an area in which said storage is located as an archiving place among said plural backup data storages on the basis of said area in which said storage is located. 18. The computer readable recording medium recorded thereon a backup controlling program according to claim 17, wherein said archiving place determining unit refers to, on the basis of information for specifying said information processing apparatus or information for specifying a user of said information processing apparatus, information for reference configured by relating said information for specifying said information processing apparatus or said information for specifying a user of said information processing apparatus to said backup data storage physically away from said area in which said storage provided to said information processing apparatus is located, and selectively determines said backup data storage as said archiving place among said plural backup data storages. 19. The computer readable recording medium recorded thereon a backup controlling program according to claim 17, wherein said backup controlling program makes said computer function as an area determining unit for determining said area in which said storage is located; said archiving place determining unit selectively determines, on the basis of said area in which said storage is located determined by said area determining unit, said backup data storage physically away from said area in which said storage is located as said archiving place among said plural backup data storages. 20. The computer readable recording medium recorded thereon a backup controlling program according to claim 17, wherein said archiving place determining unit preferentially determines a backup data storage physically farther from said area in which said storage is located as said archiving place as a degree of importance of data in said storage is higher among said plural backup data storages according to the degree of importance of data in said storage. | FIELD OF THE INVENTION The present invention relates to a backup system, a backup controlling apparatus, a backup data managing method and a computer readable recording medium recorded thereon backup controlling program suitable for use to back up data in a storage provided to, for example, a computer system connected to the Internet. DESCRIPTION OF THE RELATED ART As a method for backing up data in a hard disk integrated in or (externally) connected to a computer used by an enterprise or individual, it is general that necessary information (updatable work files and the like) in the hard disk is copied to another recording medium (for example, magnetic recording medium such as flexible disk, hard disk or the like, magneto-optical disk, DVD-R, DVD-RW, DVD-RAM or the like) using a storage [for example, magnetic storage, magneto-optical (MO) disk drive, DVD drive or the like] connected to the computer according to the intension of the user. Such backup of a hard disk is performed with a storage directly connected to the computer even when the computer is connected to another computer system over a LAN (Local Area Network), a WAN (Wide Area Network) or a telephone line. As the known backup method, it is general that only updatable work files present in the hard disk are backed up. Backup data prepared by backup or various kinds of information relating to the backup data are basically managed by the user. Patent Application Laid-Open No. HEI 11-149412 discloses an information safe-deposit box system for storing data prepared by an information device such as a PC or the like or backup data thereof in an information storage located in a remote place using a communication network such as the Internet, a personal computer communication service organization or the like, thereby to prevent important data from being lost due to disaster such as an earthquake, fire or the like. In the information safe-deposit box system disclosed in Patent Application Laid-Open No. HEI 11-149412, the user can freely access to a memory area allocated to the user in the information safe-deposit box connected to the Internet to store or read data prepared by an information device such as a PC or the like or backup data thereof. Even if the data in hard disk located in the office or house of the subscriber, or data in a stored recording medium such as a floppy disk, optical disk or the like is lost due to disaster such as an earthquake, fire or the like, the subscriber can access to the managing apparatus over the Internet to access to the allocated memory area in the information safe-deposit box after the information device in his/her office, house or the like is restored, thereby reading out the stored data. The information safe-deposit box system disclosed in Patent Application Laid-Open No. HEI 11-149412 has another information safe-deposit box (second information safe-deposit box) in a place differing from the place in which the above information safe-deposit box (first information safe-deposit box) is located, wherein, generally, backup data transmitted from the first safe-deposit box is stored in the second safe-deposit box. In case that abnormality of the first information deposit-box occurs, the user can access to the memory area of the backup data stored in the second information safe-deposit box over the Internet. In such the known backup method, it is general that the prepared backup data (recording medium) is stored in the same building or in a place in the neighborhood of the place in which the computer having the hard disk to be backed up is located. If the hard disk of the computer to be backed up is damaged or lost due to disaster such as an earthquake, flood or the like, or an accident or the like, there is danger that the backup data is simultaneously damaged together with the hard disk. The known backup method mainly targets work files present in the hard disk. When data in the hard disk becomes unusable due to an unexpected event, the operational files which have been backed up can be restored, but files of the work system, driver, application software and the like other than the work files have to be, for example, installed as well, which requires a long time and a lot of labor in order to restore the files into the original state. The management of the backup data is imposed on each of the users, which is a large load on the user who has to manage the backup data. For example, when the user does a work which causes a change in system environments of the computer such as installation of application, addition of new hardware or the like, it is general that the user backs up various kinds of data of the computer before the change in order to restore the data into the state before the change in case of emergency. When the user carries out the backup to cope with a change in the system environments as this, the user has to manage each of the prepared backup data (medium) and the features of the system at that time. In the information safe-deposit box system disclosed in Japanese Unexamined Patent Application Publication No. HEI 11-149412, a place in which the computer of the user is located and a place in which the information safe-deposit box (first information safe-deposit box) are not always geographically far from each other. When disaster or the like occurs in a place in which the computer of the user is located, there is a danger that data stored in the information safe-deposit box is lost together with data in the hard disk of the computer of the user. When the second information safe-deposit box is located in a place differing from a place in which the first information safe-deposit box is located and the backup data in the first information safe-deposit box is stored in the second information safe-deposit box, the facility investment and the operation cost increase. In the light of the above disadvantages, an object of the present invention is to provide a backup system, a backup controlling apparatus, a backup data managing method, a backup controlling program and a computer readable recording medium recording thereon the backup controlling program, whereby, even when a storage of a computer to be backed up is damaged or lost due to disaster, an accident or the like, it is possible to largely diminish a chance that the backup data in the storage sustains a damage caused by the disaster or accident, restore the storage easily and within a short time, and can configure the system with a small investment. SUMMARY OF THE INVENTION To attain the above object, a backup system according to this invention comprises a plurality of backup data storages located in areas differing from one another to archive data in a storage provided to an information processing apparatus as backup data, an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located among the plural backup data storages as an archiving place on the basis of the area in which the storage is located, and a backup processing unit for storing the backup data in the backup data storage determined as the archiving place by the archiving place determining unit. The backup system may further comprise information for reference configured by beforehand relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and the archiving place determining unit may refer to the information for reference on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup system may further comprise an area determining unit communicably connected to the information processing apparatus over a communication line, and determining an area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The backup system may further comprise a degree-of-importance designating unit for designating a degree of importance of data in the storage, and the archiving place determining unit may preferentially determine a backup data storage physically farther from the area in which the storage is located as the degree of importance is higher among the plural backup data storages according to the degree of importance designated by the degree-of-importance designating unit. The backup system may further comprise an archiving place designation inputting unit being able to selectively designate a specific backup data storage among the plural backup data storages, and the archiving place determining unit may selectively determine the backup data storage designated by the archiving place designation inputting unit as the archiving place. The backup system may further comprise an information inputting unit being able to input information about the backup data as attribute information, and the backup processing unit may relate the attribute information inputted from the information inputting unit to the backup data, and record the attribute information and the backup data. The information processing apparatus may partially extract the data from data in the storage, and prepare backup data, and the backup processing unit may archive the backup data in the backup data storage. The backup system may further comprise a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The backup system may further comprise a backup data selecting unit being able to select at least one set of backup data among plural sets of the backup data, and the restoration processing unit may restore the backup data selected by the backup data selecting unit onto the arbitrary storage. A backup controlling apparatus according to this invention for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprises an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located as an archiving place among the plural backup data storages on the basis of the area in which the storage is located. The backup controlling apparatus may further comprise information for reference configured by relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and the archiving place determining unit may refer to the information for reference on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup controlling apparatus may further comprise an area determining unit communicably connected to the information processing apparatus over a communication line, and determining the area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The archiving place determining unit may preferentially determine a backup data storage unit physically farther from the area in which the storage is located as a degree of importance of data in the storage is higher as the archiving place among the plural backup data storages according to the degree of importance of data in the storage. Information about the backup data may be related as attribute information to the backup data, and recorded. The backup controlling apparatus may further comprise a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The restoration processing unit may restore at least one set of backup data selected from plural sets of the backup data onto the arbitrary storage. A backup data managing method according to this invention for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprises an archiving place determining step of selectively determining a backup data storage physically away from an area in which the storage is located among the plural backup data storages as an archiving place on the basis of the area in which the storage is located, and a backup processing step of storing the backup data in the backup data storage determined as the archiving place at the archiving place determining step. The backup data managing method may further comprise an information-for-reference preparing step of preparing information for reference configured by relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and, at the archiving place determining step, the information for reference may be referred on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus to selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup data managing method may further comprise an area determining step of determining the area in which the storage is located, and, at the archiving place determining step, on the basis of the area in which the storage is located determined at the area determining step, the backup data storage physically away from the area in which the storage is located may be selectively determined as the archiving place among the plural backup data storages. The backup data managing method may further comprise a degree-of-importance designating step of designating a degree of importance of data in the storage, and, at the archiving place determining step, a backup data storage physically farther from the area in which the storage is located may be determined as the archiving place as the degree of importance is higher among the plural backup data storages according to the degree of importance designated at the degree-of-importance designating step. The backup data managing method may further comprise an archiving place designation inputting step at which a specific backup data storage can be selectively designated among the plural backup data storages, and, at the archiving place determining step, the backup data storage designated at the archiving place designation inputting step may be selectively determined as the archiving place. The backup data managing method may further comprise an information inputting step at which information about the backup data can be inputted as attribute information, and, at the backup processing step, the attribute information inputted at the information inputting step may be related to the backup data, and recorded. The backup data managing method may further comprise a backup data preparing step of partially extracting the data from data in the storage, and preparing backup data, and, at the backup processing step, the backup data prepared at the backup data preparing step may be archived in the backup data storage. The backup data managing method may further comprise a restoration processing step of restoring the backup data stored in the backup data storage onto an arbitrary storage. The backup data managing method may further comprising a backup data selecting step at which at least one set of backup data can be selected among plural sets of backup data, and, at the restoration processing step, the backup data selected at the backup data selecting step may be restored onto the arbitrary storage. A computer readable recording medium recorded thereon a backup controlling program according to this invention for making a computer execute a backup controlling function of archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, the backup controlling program making the computer function as an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located as an archiving place among the plural backup data storages on the basis of the area in which the storage is located. The archiving place determining unit may refer to, on the basis of information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus, information for reference configured by relating the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The computer readable recording medium recorded thereon the backup controlling program may make the computer function as an area determining unit for determining the area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The archiving place determining unit may preferentially determine a backup data storage physically farther from the area in which the storage is located as a degree of importance of data in the storage is higher as the archiving place among the plural backup data storages according to the degree of importance of data in the storage. Information about the backup data may be related as attribute information to the backup data, and recorded. The computer readable recording medium recorded thereon the backup controlling program may make the computer function as a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The restoration processing unit may restore at least one set of the backup data selected among plural sets of the backup data onto the arbitrary storage. The backup system, the backup controlling apparatus, the backup data managing method and the computer readable recording medium recorded thereon the backup controlling program according to this invention provide the following effects and advantages. (1) A backup data storage physically away from an area in which the storage is located is selectively determined as an archiving place among a plurality of backup data storages on the basis of the area in which the storage is located, and backup data is archived in the backup data storage determined as the archiving place. Accordingly, even when the storage of an information processing apparatus is damaged or lost due to disaster caused by an earthquake, flood or the like, hard disk failure or virus infection, one of various accidents such as abnormality of the operation caused by installation of a driver for connecting a new peripheral equipment or application software and the like, it is possible to diminish the possibility that the backup data storage archiving the backup data is simultaneously damaged, thereby to improve the security level of the data. Even when data in the information processing apparatus or the storage of the user is lost due to disaster such as an earthquake, fire or the like, the backup data archived in the backup storage can be restored, and contents of the storage can be restored to a state nearest to the state before the abnormality occurs, quickly and certainly, by accessing to the backup data storage over a communication line after the information processing apparatus is restored. It is possible to configure such system with the minimum facility investment. (2) An area in which the storage is located is determined, and a backup data storage physically away from the storage is selectively determined as the archiving place among a plurality of backup data storages on the basis of the determined area in which the storage is located. Accordingly, it is possible to archive the backup data in a backup data storage physically away from the storage, readily and certainly. This is very convenient. (3) The user can selectively designate a specific backup data storage among a plurality of backup data storages by means of the information processing means. Accordingly, it is possible to set an archiving place according to the intension of the user. This is very convenient. (4) Information about backup data is inputted as attribute information, and the inputted attribute information is related to the backup data and recorded in the backup data storage. Accordingly, it becomes easy to discriminate each backup data. This is very helpful when the backup data is restored onto the storage, for example. When various kinds of data in an information processing apparatus is backed up before a work which may cause a change in the system environments of the information processing apparatus such as installation of application software, addition of new hardware or the like, it is possible for the user to easily know the features of prepared backup data (medium) and the system at that time, for example. Additionally, each user does not need to manage the backup data, thus the burden on the user required to manage the backup data can be decreased. (5) Data is partly extracted from data in the storage to prepare the backup data, and the backup data is archived in the backup data storage. When this backup data is restored onto the backup data storage, the user selects at least one set of backup data among plural sets of backup data, and restores the data. Accordingly, it is possible to readily configure a storage having a data structure that the user desires. This is very convenient. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a block diagram showing a structure of a backup system according to an embodiment of this invention; FIG. 2 is a diagram schematically showing a structure of a hard disk for backup in the backup system according to the embodiment of this invention; FIG. 3 is a diagram showing an example of a management table for the hard disk for backup in the backup system according to the embodiment of this invention; FIG. 4 is a diagram showing an example of a user information database in the backup system according to the embodiment of this invention; FIG. 5 is a flowchart for illustrating a method of determining an archiving place for backup data in the backup system according to the embodiment of this invention; FIG. 6(a) is a diagram showing a list in which plural kinds of backup data managed by a backup server are arranged in time series in the backup system according to the embodiment of this invention; FIG. 6(b) is a diagram schematically showing a structure of a restored hard disk; FIG. 7 is a flowchart for illustrating a backup process in the backup system according to the embodiment of this invention; and FIG. 8 is a flowchart for illustrating a backup data restoring process in the backup system according to the embodiment of this invention. DESCRIPTION OF THE PREFERRED EMBODIMENT(S) Hereinafter, description will be made of an embodiment of this invention with reference to the drawings. FIG. 1 is a block diagram showing a structure of a backup system according to an embodiment of this invention. The backup system 1 backs up data in a hard disk (storage) 11 provided to a computer (information processing apparatus) 10 connected to the Internet 3. As shown in FIG. 1, the backup system 1 comprises a PC (Personal Computer) 10 (11a, 10b, 10c), an ISP (Internet Service Provider) 2, an ASP (Application Service Provider) 4, a backup server 5 (5a, 5b, 5c, 5d, 5e) and a hard disk 6 (6a, 6b, 6c, 6d, 6e). Each of the PCs 10a, 10b and 10c is an information processing apparatus connected to the Internet 3. In this embodiment, each of the PCs 10a, 10b and 10c is connected to the Internet 3 through the ISP 2. In this embodiment, there are three PCs, that is, the PC 10a used by user A (user), the PC 10b used by user B (user) and the PC 10c used by user C (user). The users A, B and C use specific PCs 10a, 10b and 10c, respectively. The PC 10a is located in Sapporo, the PC 10b in Tokyo, and the PC 10c in Fukuoka. The PC 10a is connected to the ISP 2 over an ISDN (Integrated Services Digital Network). The PC 10a is connected to the Internet 3 by dialing-up an access point of the ISP 2 to be connected thereto using a TA 12. The PC 10c is connected to the ISP 2 over a public telephone line. The PC 10c is connected to the Internet 3 by dialing-up an access point of the ISP 2 to be connected to thereto, using a modem 14. The PC 10b is connected to the ISP 2 over an ADSL (Asymmetric Digital Subscriber Line). The PC 10b is connected to the Internet 3 by connecting to a POI (Point of Interface) with the ISP 2 using an ADSL modem 13. Hereinafter, reference character 10a, 10b or 10c is used when it is necessary to specify one of the plural PCs. When an arbitrary PC is designated, reference character 10 is used. Each of the hard disks 11a, 11b and 11c is a magnetic storage device (storage) which stores various kinds of data and programs in a way that the computer can read them. The hard disk 11a is connected to the PC 10a. Similarly, the hard disk 11b is connected to the PC 11b, and the hard disk 11c is connected to the PC 11c. In this embodiment, at least a part of the data stored in each of the hard disks 11a, 11b and 11c is stored as backup data in a hard disk for backup 6 (6a, 6b, 6c, 6d or 6e) to be described later. In this backup system 1, the hard disk (magnetic storage device) is used as the storage, but this invention is not limited to this. For example, another computer readable recording media such as a memory, flexible disk, memory card, magneto-optical storage device, CD-ROM, CD-R, CD-RW, DVD, DVD-R, DVD-RW or the like may be used as the storage. Hereinafter, when it is necessary to specify one of the plural hard disks, reference character 11a, 11b or 11c is used as a reference character designating the hard disk. When an arbitrary hard disk is designated, reference character 11 is used. The PC 10 selects and extracts at least a part of data stored in the hard disk 11 as backup data, and transmits the data to a backup server 5 (5a, 5b, 5c, 5d or 5e) managed by the ASP 4 to be described later. The backup data may be prepared by partially extracting a data area in which data that can be updated by various programs is stored, a boot area in which data relating to the system is stored, an OS (Operating System) area, an application (APL) area, a maintenance information area in which information about maintenance of the system is stored, and the like from data stored in the hard disk 11, for example. Alternatively, it is possible to prepare the whole data in the hard disk 11 as a disk image. In this embodiment, the PC 10a and the hard disk 11a connected to the PC 10a are located in places physically in proximity to each other. Similarly, the PC 10b and the hard disk 11b connected to the PC 10b are located in places physically in proximity to each other, and the PC 10c and the hard disk 11c are located in places physically in proximity to each other. In this embodiment, the area in which the PC 10 is located is equivalent to the area in which the hard disk 11 is located. It is thus possible to determine the place in which the hard disk 11 is located by determining the area in which the PC 10 is located. The ISP (Internet Service Provider) 2 provides a connection service to the Internet to the users (in this embodiment, user A, user B and user C; users). The ISP 2 provides an access point to be accessed from the modem 14 or the TA 12, or provides a point of interface (POI) with the ADSL, thereby providing a destination to be connected over the Internet to the user. The Internet (communication line) 3 is a huge network formed by connecting computer networks such as LANs (Local Area networks), WANs (Wide Area Networks) and the like scattered in many places to one another. The user connects the PC 10 to the Internet 3, thereby receiving various services provided over the Internet 3 or share various kinds of information present on the Internet 3. In this system 1, the PC 10 (10a, 10b, 10c) is so connected to the ASP 4, the backup server 5 (5a, 5b, 5c, 5d, 5e) and the hard disk for backup 6 (6a, 6b, 6c, 6d, 6e) as to be able to communicate with the same. The application service provider (ASP) 4 (service providing company or the like) provides application functions over the Internet 3. The ASP 4 is realized with a computer having the server function. The ASP 4 collectively operates applications in a data center called a server firm to distribute the functions of the applications to the users (PC 10) connected over the Internet 3. In this backup system 1, the ASP 4 sets a unique identification code (contract account) and a password to each user. The ASP 4 demands a person who connects (accesses) to the ASP 4 over the Internet 3 to input the contract account and the password, determines that the person who is having an access is a proper person (contractor) only when both of the inputted contract account and password completely match with those entered in a user information database 43 (to be described later) of the ASP 4, then provides the service. A plurality (five in FIG. 1) of backup servers (backup processing units, restoration processing units) 5a, 5b, 5c, 5d and 5e are connected to the ASP 4. The backup servers 5a, 5b, 5c, 5d and 5e manage the hard disks for backup 6a, 6b, 6c, 6d and 6e, respectively. Each of the backup servers 5a, 5b, 5c, 5d and 5e is comprised of a computer having the server function, for example. In this backup system 1, the hard disk for backup 6a is connected to the backup server 5a, the hard disk 6b to the backup server 5b, the hard disk for backup 6c to the backup server 5c, the hard disk for backup 6d to the backup server 5d, and the hard disk for backup 6e to the backup server 5e, as shown in FIG. 1. The backup server 5a controls storing of data in the hard disk for backup 6b and reading of data from the hard disk for backup 6a. Similarly, the backup server 5b controls storing of data in the hard disk for backup 6b and reading of data from the hard disk for backup 6b, the backup server 5c controls storing of data in the hard disk for backup 6c and reading of data from the hard disk for backup 6c, the backup server 5d controls storing of data in the hard disk for backup 6d and reading of data from the hard disk for backup 6d, and the backup server 5e controls storing data in the hard disk for backup 6e and reading data from the hard disk for backup 6e. Namely, each of the backup servers 5a, 5b, 5c, 5d and 5e controls the data reading/writing process on the hard disk for backup 6a, 6b, 6c, 6d or 6e to store backup data in the hard disk for backup 6a, 6b, 6c, 6d or 6e (backup process), or to read out the backup data recorded on the hard disk for backup 6a, 6b, 6c, 6d or 6e, and transfers the data to a specific PC 10 (restoring process), for example. Each of the hard disks for backup (backup data storing units) 6a, 6b, 6c, 6d and 6e is a storage (magnetic storage device) storing various data in such a way that the computer can read out the data. In this backup system 1, a hard disk is used as the backup data storage. However, this invention is not limited to this. It is possible to use another kind of computer readable recording medium such as a memory, flexible disk, memory card, magneto-optical storage device, CD-ROM, CD-R, CD-RW, DVD, DVD-R, DVD-RW or the like. The backup server 5a and the hard disk for backup 6a, the backup server 5b and the hard disk for backup 6b, the backup server 5c and the hard disk for backup 6c, the backup server 5d and the hard disk for backup 6d, and the backup server 5e and the hard disk for backup 6e are located in areas differing from one another. In this backup system 1, the backup server 5a and the hard disk for backup 6a are located in Fukuoke, the backup server 5b and the hard disk for backup 6b in Tokyo, the backup server 5c and the hard disk for backup 6c in Osaka, the backup server 5d and the hard disk for backup 6d in Sapporo, and the backup server 5e and the hard disk for backup 6e in Okinawa. Hereinafter, when it is necessary to specify one of the plural backup servers, reference character 5a, 5b, 5c, 5d or 5e is used as the reference character designating the backup server. When an arbitrary backup server is designated, reference character 5 is used. Similarly, when it is necessary to specify one of the plural hard disks for backup, reference character 6a, 6b, 6c, 6d or 6e is used as reference character designating the hard disk for backup. When an arbitrary hard disk for backup is designated, reference character 6 is used. In this embodiment, the backup server 5a and the hard disk for backup 6a connected to the backup server 5a are located in areas physically in proximity of each other. Similarly, the backup server 5b and the hard disk for backup 6b are located in areas physically in proximity of each other, as well as the backup server 5c and the hard disk for backup 6c, the backup server 5d and the hard disk for backup 6d, and the backup server 5e and the hard disk for backup 6e. FIG. 2 is a diagram schematically showing a structure of the hard disk for backup 6 in the backup system according to the embodiment of this invention. As shown in FIG. 2, areas (user allocated areas 1 through n) for archiving backup data of respective contracting users are set in the hard disk for backup 6. Incidentally, n is a natural number representing the number of users, and the number of set user allocated areas is equal to the number of the users. Each of the user allocated areas 1 through n has a plurality of storing areas 1 through x. The user can archive backup data in each of the storing areas. Incidentally, x is a natural number representing the number of the storing areas set in the user allocated area. The storing area is given a number in time series each time the user performs the backup, the number representing the number of times the user performs the backup. It is possible to extract an arbitrary part such as the data area, the boot area, the OS area, the application area, the maintenance information area or the like from various kinds of data stored in the hard disk 11, and archive the data as backup data in each of the storing areas 1 through x, as described above. At the time of the backup, the user may archive at least a part of the data in the hard disk 11 as the backup data as it is without processing it, or may perform a process such as compression or the like on at least a part of the data in the hard disk 11 and archive the data as the backup data. Feature information or attribute information can be related to each of the storing areas. Namely, information about backup data to be archived in each of the storing area can be related to the backup data, and archived. The feature information is information showing the features of the backup data, which is, for example, a date when the backup is performed, features of the data at the time of the backup, information about compression (compressed or not, form of the compression, etc.), data capacity, etc. This information is mainly used when data relating to the system [for example, boot area, OS (Operating System) area, application (APL) area] is backed up. The attribute information is information relating to information on a file to be backed up, backup schedule, etc., which is mainly used when an updatable data file is backed up. FIG. 3 is a diagram showing an example of a management table for the hard disk for backup 6 in the backup system 1 according to the embodiment of this invention, which shows contents of backup data archived in the user allocation area of a certain user. The management table shown in FIG. 3 is managed by the ASP 4 or the backup server 5. An item named “section” in the management table is set correspondingly to the above storing area in FIG. 2, for the sake of convenience. The sections 1 through x correspond to the storing areas 1 through x in FIG. 2, respectively, each of which specifies a specific storage area on the hard disk for backup 6. Each time the user performs the backup, a new column is added (x=x+1) as the section in the management table. In the example shown in FIG. 3, each of the sections has a plurality (three in FIG. 3) of areas. In this embodiment, an item named “classification” is set to these areas, for the sake of convenience. Each of the classifications 1 through 3 specifies a specific storage area on the hard disk for backup 6. In the example shown in FIG. 3, backup data in the boot area, the OS area, the application area on the hard disk 11 is archived in an area corresponding to the classification 1 in the hard disk for backup 6. The data area on the hard disk 11 is archived in an area corresponding to the classification 2. The maintenance information area on the hard disk 11 is archived in an area corresponding to the classification 3. Items of area information, date and feature are related to the data archived in each of the classifications. The area information shows contents of the data. The area information shows which area on the hard disk 11 the data is stored in. The date is a date when the user performs the backup. The feature is information showing the type or the like of the OS. Whereby, it is found that backup data in the boot area, the OS area and the application area on the hard disk 11 was archived in Jan. 1, 2002 in an area corresponding to the classification 1 in the section 1 in the hard disk for backup 6, for example. It is also found that the data in only the boot area, the OS area and the application area was backed up in Jan. 1, 2002, but data in the data area or the maintenance information area was not archived on the day. Similarly, it is found that backup data in the data area on the hard disk 11 was archived in Feb. 1, 2002 in an area corresponding to the classification 2 in the section 2 in the hard disk for backup 6, for example. It is also found that data in the boot area, the OS area, the application area and the maintenance area was backed up in Feb. 1, 2002. The APS 4 comprises an area determining unit 41, an archiving place determining unit 42 and a user information database (information for reference) 43, as shown in FIG. 1. The user information database 43 retains various kinds of information on each of the users. For example, name of the user, postal code, telephone number and address of a place in which the PC 10 used by the user is located, information on the type of the PC, password, etc., are related to the contract account of the user and recorded, whereby the user information database manages various kinds of information that can be used to specify the place in which the PC 10 used by the user is located. FIG. 4 is a diagram showing an example of the user information database 43 in the backup system 1 according to the embodiment of this invention. In the example shown in FIG. 4, the user information database 43 has contractor information and archive information. The contractor information is information relating to a place where the user (or the PC 10 or the hard disk 11 that the user uses) is, which is configured by relating the postal code or telephone number to the contractor account. Incidentally, the archive information will be described later. A contract account “ABC” is identification information set to the user C, for example. A postal code (812-0000) or a telephone number (011-***-****) shows that a place where the user is, Fukuoka Prefecture for example, is related to the contract account, and recorded. Similarly, a contract account “EFG” is identification information set to the user A. A postal code (060-0000) or a telephone number (092-***-****) shows that a place where the user A is, Hokkaido for example, is related to the contract account, and recorded. In this embodiment, each user uses a specific PC 10. For this, it is possible to specify the user of the PC 10 or the PC 10 by obtaining a contract account used in an access to the ASP 4 and referring to the user information database 43 on the basis of the contract account. Namely, the contract account functions as information for specifying the PC (information processing apparatus) 10 or information for specifying the user of the PC (information processing apparatus) 10. In the user information database 43, a result of backup having been performed on the hard disk for backup 6 is related to the contract account, and stored as the archive information. In the example shown in FIG. 4, archive designation, section, classification and archiving place are recorded as the archive information. The archive information is an item for recording whether the archiving place is determined by default or by user's designation (designated archiving place). In the item of the archive designation, information showing “default” or “designated archiving place” is recorded. The section and the classification are the section and classification in the management table shown in FIG. 3, which are items in which information showing an area in which the backup data is archived is recorded. The archiving place is an item, in which information for specifying the hard disk for backup 6 in the archiving place of the backup data or the backup server 5 controlling the hard disk for backup 6 is recorded. The information recorded as the archive information is not limited to the archive designation, section, classification and/or archiving place described above. Alternatively, it is possible to record various kinds of information relating to the backup such as a date when the backup was performed, area information, feature, attribute, etc. The area determining unit 41 determines an area in which the PC 10 connected to the ASP 4 is located. On the basis of the contractor information retained in the user information database 43, the area determining unit 41 determines an area in which the PC 10 is located. In concrete, the area determining unit 41 refers to the user information database 43 on the basis of the contract account of the user inputted when the user accesses to the ASP 4, obtains a postal code or a telephone number of the user from the contractor information, and calculates (obtains) an area in which the PC 10 of the user is located on the basis of the postal code or the telephone number. Since postal codes or toll numbers of telephone numbers are set to different numbers according to the areas, it is possible to specify an area in which the user resides by using a postal code or telephone number. In this embodiment, characteristics of postal code or telephone number are used to specify an area in which the user resides (or an area in which the PC 10 and the hard disk 11 are located). However, this invention is not limited to this example. Alternatively, at least a part of the address of the user may be beforehand retained in the user information database 43 to be used, for example. As this, the present invention may be modified in various ways without departing from the scope of the invention. The method of determining the area in which the PC 10 is located by means of the area determining unit 41 is not limited to a method in which the area in which the PC 10 is located is obtained on the basis of the contractor information beforehand registered. Alternatively, it is possible to determine an area in which the PC 10 is located on the basis of an access point used when the PC 10 is connected to the ISP 2, or obtain an IP (Internet Protocol) address set to the PC 10 and determine an area in which the PC 10 is located on the basis of the obtained IP address. As this, this invention may be modified in various ways without departing from the scope of the invention. The archiving place determining unit 42 determines an archiving place for backup data of the hard disk 11 connected to the PC 10 on the basis of the area in which the PC 10 is located determined by the area determining unit 41. The archiving place determining unit 42 selects at least one hard disk for backup 6 located in a place physically (geographically) farthest from the area in which the PC 1 is located, which is determined by the area determining unit 41 among the plural (five in this embodiment) hard disks for backup 6 (6a, 6b, 6c, 6d and 6e), on the basis of the area in which the PC 10 of the user is located determined by the area determining unit 41 and areas in which the hard disks for backup 6 (6a, 6b, 6c, 6d and 6e) in the backup system 1 are located, and determines the selected hard disk for backup 6 as the archiving place for the backup data. As the method of selecting a hard disk for backup 6 physically farthest from the area in which the PC 10 is archived, a distance between the PC 10 and the backup server 5 (hard disk for backup 6) is calculated on the basis of coordinates information (arbitrary coordinate space, the north latitude and the east longitude, etc.) and coordinates information on each of the backup servers 5 (hard disks for backup 6), and an archiving place is determined on the basis of a result of the calculation. For example, when data in the PC 10a of the user A is backed up, the archiving place determining unit 42 selects a hard disk for backup 6e located in Okinawa that is a place farthest from Sapporo in the backup system 1 as the archiving place for the backup data, and determines it. The backup data is archived in the hard disk for backup 6e by means of the backup server 5e. Similarly, when the user c using the PC 10c in Fukuoka backs up data in the hard disk 11c of the PC 10c, the archiving place determining unit 42 selects the backup server 5d located in Sapporo that is a place farthest from Fukuoka as the archiving place for the backup data, and determines it. Whereby, the backup data is archived in the hard disk for backup 6e by means of the backup server 5e. In the backup system 1, the archiving place determining unit 42 basically selects a hard disk for backup 6 physically farthest from an area in which the PC 10 is located as the backing-up place, as above. Hereinafter, the backing-up place (hard disk for back up 6) selected and determined by the archiving place determining unit 42 is occasionally referred to as the backing-up place by default. In the backup system 1, the user can select an arbitrary hard disk for backup 6 among the plural hard disks for backup 6 as the archiving place for the backup data. When the user desires to archive the backup data in a place other than the backing-up place by default determined by the archiving place determining unit 42, the user can beforehand select an arbitrary hard disk for backup 6 among the plural hard disks for backup 6 equipped in the backup system 1, by using the PC 10. Namely, the PC 10 functions as an archiving place designation inputting unit which can selectively designate a specific hard disk for backup 6 among the plural hard disks for backup 6. Next, a method for determining an archiving place for backup data in the backup system 1 according to the embodiment of this invention will be described with reference to a flowchart (steps A10 through A70) shown in FIG. 5. The ASP 4 refers to the above flag to read a storage designating method of whether backup data is archived in a backing-up place by default or the backup data is archived in a hard disk for backup selected by the user (step A10), and determines whether or not the backup data is archived in the backing-up place by default (hard disk for backup 6) (step A20). When the backup data is archived in the backing-up place by default (refer to YES route at step A20), the ASP 4 refers to the contract account of the user to obtain a postal code or telephone number of the user from the user information database 43 (step A30). The area determining unit 41 determines an area in which a PC 10 of the user is located on the basis of the obtained postal code or telephone number (area determining step). The archiving place determining unit 42 selects and determines a backup server 5 (hard disk for backup 6) located in a place geographically farthest from the place in which the PC 10 is located, on the basis of the area in which the PC 10 (hard disk 11) is located determined by the area determining unit 41 and the area in which the hard disk for backup 6 is located (step A40; archiving place determining step), and determines the backup server 5 (hard disk for backup 6) as the archiving server (step A50). On the other hand, when the backup data is not archived in the backing-up place by default (refer to NO route at step A20), the user selects an arbitrary backing-up place (hard disk for backup 6) using the PC 10 (step A60; archiving place designation inputting step). The archiving place determining unit 42 obtains the designated hard disk for backup 6 (step A70). The procedure then moves to step A50. At least a part of data in the hard disk 11 is archived as the backup data in the hard disk for backup 6 determined as above as the archiving place for the backup data (backup process step). In this embodiment, determination on an area in which the PC 10 is located by the area determining unit 41 or determination on an archiving place for the backup data by the archiving place determining unit 42 is performed each time the user carries out the backup. Since these processes are performed by not much complicated algorithm, the ASP 4 is not required to bear excessively large load. It is thus considered that these processes do not exert adverse effect even if these processes are performed each time the user carries out the backup. In the backup system 1, the backup data archived in the hard disk for backup 6 can be restored onto the hard disk 11 of each of the PCs 10. At this time, the user can select arbitrary backup data in the plural sets of backup data archived in the hard disk for backup 6, using the PC 10. The backup server 5 obtains the selected backup data from the hard disk for backup 6, and transmits the data to the PC 10 that the user uses. The PC 10 receiving the backup data from the backup server 5, for example, overwrites the backup data on the hard disk 11 to restore the backup data. FIG. 6(a) is a diagram showing a list in which plural kinds of backup data managed by the backup server 5 in the backup system 1 are arranged in time series according to the embodiment of this invention. FIG. 6(b) is a diagram schematically showing a structure of the restored hard disk 11. As shown in FIG. 6(a), the backup server 5 can show plural sets of backup data corresponding to a contract account of a certain user as a list in which the data is arranged in time series to the user accessing to the ASP 4 using the PC 10 in order to restore the backup data. The user can arbitrarily select backup data that the user desires to restore in the list of the backup data. The backup server 5 transmits the backup data so selected to the hard disk 11 of the PC 10 to restore the disk image thereof. When the user selects backup data to be restored, the user can select only a part of the backup data in such a manner that the user selects only the backup data (data area) stored in the data area (classification 3) in the section 5, or select all the data (classifications 1 to 3) in the sections n, for example. Alternatively, as shown in FIG. 6(b), the user may selectively combine backup data in different sections in such a manner that the user selects backup data in the classification 3 in the section n, backup data in the classification 2 in the section 4 and backup data in the classification 1 in the section 2, for example. Whereby, it is possible to form a disk image in a state that the user desires on the hard disk 11. Namely, the PC 10 functions as a backup data selecting unit which can select at least one set of backup data from plural sets of backup data. The backup server 5 and the PC 10 together function as a restoring process unit which restores backup data stored in the hard disk for backup 6 onto an arbitrary hard disk 11. Next, description will be made of a back up process in the backup system 1 according to the embodiment of this invention structured as above with reference to a flowchart (steps B10 through B40) shown in FIG. 7. When the user starts the PC 10, the OS is started (step B10), and the PC 10 is connected to the Internet 3 through the ISP 2. The user has an access to the ASP 4 (accesses to the network) using the PC 10 (step B20). When having an access to the ASP4, the user inputs a contract account or password beforehand set. After having an access to the ASP 4, the user selects data (data area) to be backed up on the hard disk 11. The archiving place determining unit 42 determines an archiving place for the backup data (step B30). The determination on the archiving place is performed according to the flowchart shown in FIG. 5. In order to archive the selected data in the hard disk for backup 6, which is the archiving place determined by the archiving place determining unit 42, the ASP 4 selects a backup server 5 managing the hard disk for backup 6. The selected backup server 5 obtains the backup data from the PC 10 (hard disk 11), and archives the backup data in a predetermined area on the hard disk for backup 6 (step B40). Next, description will be made of a backup data restoring process in the backup system 1 according to the embodiment of this invention with reference to a flowchart (steps C10 through C50) shown in FIG. 8. When the user starts the PC 10, the OS is started (step C10), and the PC 10 is connected to the Internet 3 through the ISP 2. The user has an access to the ASP 4 (accesses to the network) using the PC 10 (step C20). When having an access to the ASP4, the user inputs a contract account or password beforehand set. The ASP 4 transmits a list of backup data as shown in FIG. 6(a) to the PC 10, displays the list on a display (not shown) of the PC 10 (step C30). The user arbitrarily selects backup data to be restored onto the hard disk 11 in the backup data (step C40). The backup server 5 transmits the selected backup data to the hard disk 11 of the PC 10, and restores a disk image of the data in cooperation with the PC 10 (step C50). In the backup system 1 according to the embodiment of this invention, the archiving place determining unit 42 determines a backup data storage physically (geographically) far from an area in which the hard disk 11 (PC 10) is located among the plural hard disks for backup 6 as the archiving place on the basis of the area in which the hard disk 11 (PC 10) is located. The backup server 5 archives the backup data in the hard disk for backup 6 determined as the archiving place. Even when the hard disk 11 of the PC 10 is damaged or lost due to disaster caused by an earth quake, flood or the like, or an accident such as hard disk failure, infection of virus, operation abnormality caused by installation of a driver or application for connecting a new peripheral equipment, etc., it is possible to diminish a risk that a hard disk for backup 6 archiving the backup data therein is simultaneously damaged, and improve the security level of the data. Even when data in the PC 10 or the hard disk 11 of the user is lost due to disaster such as an earth quake, fire or the like, it is possible to restore the data with the backup data archived in the hard disk for backup 6 by accessing to the ASP 4 over the Internet 3 after the PC 10 is restored, for example. In case of disaster, an accident or the like, it is also possible to restore the contents of the hard disk 11 of the PC 10, quickly and certainly, to a state closest to the state before the abnormality occurs on the basis of contents backed up by the ASP 4. Such system can be established with the minimum facility investment. The area determining unit 41 determines an area in which the hard disk 11 (PC 10) is located, and the archiving place determining unit 42 selectively determines a hard disk for backup 6 physically far from the hard disk 11 as the archiving place among the plural hard disks for backup 6 on the basis of the area in which the hard disk 11 is located determined by the area determining unit 41. Accordingly, it is possible to archive the backup data, readily and certainly, in a hard disk for backup 6 physically far from the hard disk 11. This is very useful. Further, the user can selectively designate a specific hard disk for backup 6 among the plural hard disks for backup 6, using the PC 10. Accordingly, it is possible to set an archiving place that the user desires. This is very convenient. Information relating to the backup data is inputted as attribute information from the PC 10 or the like, and the inputted attribute information is related to the backup data and recorded on the hard disk for backup 6. Accordingly, discrimination of each backup data becomes easily. This is very helpful when the backup data is restored onto the hard disk 11. When various kinds of data in the PC is backed up before a work that may cause a change in the system environments of the PC 10 such as installation of an application, addition of new hardware or the like, it is possible to readily know the created backed up data and the features of the system at that time. It is unnecessary for each user to manage the backup data, which can reduce the burden on the user required for the management. When data is partly extracted from data in the hard disk 11 to make backup data, and the backup data is archived on the hard disk for backup 6 and restored onto the hard disk 11, the user selects at least one set of backup data from the plural sets of backup data and restores the data. Thus, the user can readily form the hard disk having a data structure that the user desires. This is very helpful. At this time, not only work files (data area) present on the hard disk 11 but also each of the boot area, the OS area, the maintenance area and the data area can be archived as the backup data and restored. This can omit a work of installing the OS file, driver file, application software and the like other than the work files. This is very helpful. The CPU (Central Processing Unit) of the information processing apparatus functions as the above area determining unit 41 and the archiving place determining unit 42 by executing a program stored in a computer readable recording medium (for example, memory, magnetic storage device, flexible disk, memory card, magneto-optical storage device, CD-ROM, CD-R, CD-RW, DVD, DVD-R, DVD-RW or the like). The program (backup controlling program) for realizing the functions of the area determining unit 41 and the archiving place determining unit 42 is recorded on a computer readable recording medium such as a flexible disk, CD-ROM, CD-R, CD-R/W, DVD, DVD-R, DVD-R/W, magnetic disk, optical disk, magento-optical disk or the like, and provided. The computer reads out the program from the recording medium, transfers the program to the internal storage or an external storage, stores the program therein, and uses the program. Alternatively, the program may be recorded on a storage (recording medium) such as a magnetic disk, optical disk, magneto-optical disk or the like, for example, and provided to the computer from the storage over a communication line. When the functions of the area determining unit 41 and the archiving place determining unit 42 are realized, the program stored in the internal storage (RAM or ROM of a printer in this embodiment) is executed by the microprocessor of the computer (CPU of the printer in this embodiment). Alternatively, the computer may read the program stored in the recording medium and execute the same, at this time. In this embodiment, “computer” is a concept including hardware and an operating system, which signifies hardware operating under the control of the operating system. When the hardware is operated by only the application program without necessity of the operating system, the hardware itself corresponds to the computer. The hardware has at least a microprocessor such as a CPU or the like and a means for reading the computer program recorded on the recording medium. In this embodiment, each of the ASP4, the PC 10 and the backup server 5 has a function as the computer. As the recording medium according to this embodiment, usable are various types of computer readable media such as IC card, ROM cartridge, magnetic tape, punched card, internal storage (memory such as RAM or ROM) of the computer, external storage, printed matter on which codes such as bar codes or the like are printed and the like other than the above flexible disk, CD-ROM, CD-R, CD-R/W, DVD, DVD-R, DVD-R/W, magnetic disk, optical disk, magneto-optical disk and the like. Note that the present invention is not limited to the above embodiment, but may be modified in various ways without departing from the scope of the invention. For example, the method for connecting the PC 10 to the Internet 3 is not limited to the above example, but the PC 10 may be connected to the Internet 3 in any one of various ways by means of a cable television, radio, optical fiber and the like. The determination in the archiving place designation method is not limited to determination using a flag as above, but various methods are applicable. In the above embodiment, the backup servers 5 (hard disks for backup 6) are located in five areas, that is, Fukuoka, Tokyo, Osaka, Okinawa and Sapporo, but the places in which the backup servers 5 are located are not limited to the above places. The backup servers 5 may be located in four places or less, or six places or more differing from one another. If the backup servers 5 (hard disks for backup 6) are located in areas away from each other across the sea (for example, Hokkaido and Honshu, or Honshu and Hokkaido, etc.), or areas in different earthquake zones, the effect of disaster such as an earthquake or the like can be held down to the minimum. In the above embodiment, the contract account functions as information for specifying the PC (information processing apparatus) 10 or information for specifying the user of the PC (information processing apparatus) 10, but this invention is not limited to this. Other various kinds of information may be used as information for specifying the PC 10 or information for specifying the user of the PC 10. In which case, a specific hard disk for backup 6 is beforehand set as the backing-up place by default for each of the users, and the archiving place determining unit 42 selects a hard disk for backup 6 on the basis of this information. Whereby, it becomes unnecessary to determine the archiving place for backup data by calculation each time, and it becomes possible to reduce the load on the ASP 4. Alternatively, a hard disk for backup 6 (backup server 5) in an archiving place may be beforehand set for each user in a table or the like (information for reference; for example, the user information database 43 or the like), and the archiving place determining unit 42 may determine an archiving place for backup data by referring to the table. Still alternatively, the user may set the degree of importance to each backup data, and may preferentially set a hard disk for backup 6 farther from the area in which the hard disk 11 is located as the archiving place as the degree of importance is higher among the plural hard disk for backup 6 according to the importance. The degree of importance may be set to each of the data area, the boot area, the OS area, the application area and the maintenance information area, or may be set to each data. In the above embodiment, an arbitrary part of various kinds of information stored in the hard disk 11 such as the data area, the boot area, the OS area, the application area, the maintenance information area, etc. is extracted as the backup data, and archived. However, this invention is not limited to this example. The whole data in the hard disk 11 may be retained as the backup data. In the above embodiment, as a method of selecting a hard disk for backup 6 physically farthest from the area in which the PC 10 is located, a distance between the PC 10 and the backup server (hard disk for backup 6) is calculated on the basis of coordinates information (arbitrary coordinate space, or the north latitude and east longitude, etc.) on an area specified on the basis of a postal code or telephone number, and coordinates information on each of the backup servers 5 (hard disks for backup 6). This invention is not limited to this example. This invention may be modified in various ways without departing from the scope of the invention. For example, a hard disk for backup 6 may be beforehand set as the archiving place in each area, using another algorithm. In the above embodiment, the ASP 4 provides, as the application function, the backup function of archiving data in the hard disk 11 of the PC 10 as the backup data in at least one of the plural hard disks located in different areas. However, this invention is not limited to this example. The ASP 4 may provide various application functions other than the backup function. As these application functions, there are various application functions for the basic operation system such as finance, accounting, personnel and the like, the front office system such as group ware, business support and the like, the specialized business system supporting specific type/service of business such as warehouse business, restaurant and food service business and the like, the EC (Electronic Commerce) site system, etc. Meanwhile, disclosure of the embodiment of this invention enables persons skilled in the art to manufacture the invention. Industrial Applicability The backup system, the backup controlling apparatus, the backup of data managing method and the computer readable recording medium on which the backup controlling program is recorded according to this invention are suited to back up a storage of an information processing apparatus such as a computer or the like, as described above. | <SOH> FIELD OF THE INVENTION <EOH>The present invention relates to a backup system, a backup controlling apparatus, a backup data managing method and a computer readable recording medium recorded thereon backup controlling program suitable for use to back up data in a storage provided to, for example, a computer system connected to the Internet. | <SOH> SUMMARY OF THE INVENTION <EOH>To attain the above object, a backup system according to this invention comprises a plurality of backup data storages located in areas differing from one another to archive data in a storage provided to an information processing apparatus as backup data, an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located among the plural backup data storages as an archiving place on the basis of the area in which the storage is located, and a backup processing unit for storing the backup data in the backup data storage determined as the archiving place by the archiving place determining unit. The backup system may further comprise information for reference configured by beforehand relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and the archiving place determining unit may refer to the information for reference on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup system may further comprise an area determining unit communicably connected to the information processing apparatus over a communication line, and determining an area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The backup system may further comprise a degree-of-importance designating unit for designating a degree of importance of data in the storage, and the archiving place determining unit may preferentially determine a backup data storage physically farther from the area in which the storage is located as the degree of importance is higher among the plural backup data storages according to the degree of importance designated by the degree-of-importance designating unit. The backup system may further comprise an archiving place designation inputting unit being able to selectively designate a specific backup data storage among the plural backup data storages, and the archiving place determining unit may selectively determine the backup data storage designated by the archiving place designation inputting unit as the archiving place. The backup system may further comprise an information inputting unit being able to input information about the backup data as attribute information, and the backup processing unit may relate the attribute information inputted from the information inputting unit to the backup data, and record the attribute information and the backup data. The information processing apparatus may partially extract the data from data in the storage, and prepare backup data, and the backup processing unit may archive the backup data in the backup data storage. The backup system may further comprise a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The backup system may further comprise a backup data selecting unit being able to select at least one set of backup data among plural sets of the backup data, and the restoration processing unit may restore the backup data selected by the backup data selecting unit onto the arbitrary storage. A backup controlling apparatus according to this invention for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprises an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located as an archiving place among the plural backup data storages on the basis of the area in which the storage is located. The backup controlling apparatus may further comprise information for reference configured by relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and the archiving place determining unit may refer to the information for reference on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup controlling apparatus may further comprise an area determining unit communicably connected to the information processing apparatus over a communication line, and determining the area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The archiving place determining unit may preferentially determine a backup data storage unit physically farther from the area in which the storage is located as a degree of importance of data in the storage is higher as the archiving place among the plural backup data storages according to the degree of importance of data in the storage. Information about the backup data may be related as attribute information to the backup data, and recorded. The backup controlling apparatus may further comprise a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The restoration processing unit may restore at least one set of backup data selected from plural sets of the backup data onto the arbitrary storage. A backup data managing method according to this invention for archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, comprises an archiving place determining step of selectively determining a backup data storage physically away from an area in which the storage is located among the plural backup data storages as an archiving place on the basis of the area in which the storage is located, and a backup processing step of storing the backup data in the backup data storage determined as the archiving place at the archiving place determining step. The backup data managing method may further comprise an information-for-reference preparing step of preparing information for reference configured by relating information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and, at the archiving place determining step, the information for reference may be referred on the basis of the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus to selectively determine the backup data storage as the archiving place among the plural backup data storages. The backup data managing method may further comprise an area determining step of determining the area in which the storage is located, and, at the archiving place determining step, on the basis of the area in which the storage is located determined at the area determining step, the backup data storage physically away from the area in which the storage is located may be selectively determined as the archiving place among the plural backup data storages. The backup data managing method may further comprise a degree-of-importance designating step of designating a degree of importance of data in the storage, and, at the archiving place determining step, a backup data storage physically farther from the area in which the storage is located may be determined as the archiving place as the degree of importance is higher among the plural backup data storages according to the degree of importance designated at the degree-of-importance designating step. The backup data managing method may further comprise an archiving place designation inputting step at which a specific backup data storage can be selectively designated among the plural backup data storages, and, at the archiving place determining step, the backup data storage designated at the archiving place designation inputting step may be selectively determined as the archiving place. The backup data managing method may further comprise an information inputting step at which information about the backup data can be inputted as attribute information, and, at the backup processing step, the attribute information inputted at the information inputting step may be related to the backup data, and recorded. The backup data managing method may further comprise a backup data preparing step of partially extracting the data from data in the storage, and preparing backup data, and, at the backup processing step, the backup data prepared at the backup data preparing step may be archived in the backup data storage. The backup data managing method may further comprise a restoration processing step of restoring the backup data stored in the backup data storage onto an arbitrary storage. The backup data managing method may further comprising a backup data selecting step at which at least one set of backup data can be selected among plural sets of backup data, and, at the restoration processing step, the backup data selected at the backup data selecting step may be restored onto the arbitrary storage. A computer readable recording medium recorded thereon a backup controlling program according to this invention for making a computer execute a backup controlling function of archiving data in a storage provided to an information processing apparatus as backup data in at least one of a plurality of backup data storages located in areas differing from one another, the backup controlling program making the computer function as an archiving place determining unit for selectively determining a backup data storage physically away from an area in which the storage is located as an archiving place among the plural backup data storages on the basis of the area in which the storage is located. The archiving place determining unit may refer to, on the basis of information for specifying the information processing apparatus or information for specifying a user of the information processing apparatus, information for reference configured by relating the information for specifying the information processing apparatus or the information for specifying a user of the information processing apparatus to the backup data storage physically away from the area in which the storage provided to the information processing apparatus is located, and selectively determine the backup data storage as the archiving place among the plural backup data storages. The computer readable recording medium recorded thereon the backup controlling program may make the computer function as an area determining unit for determining the area in which the storage is located, and the archiving place determining unit may selectively determine, on the basis of the area in which the storage is located determined by the area determining unit, the backup data storage physically away from the area in which the storage is located as the archiving place among the plural backup data storages. The archiving place determining unit may preferentially determine a backup data storage physically farther from the area in which the storage is located as a degree of importance of data in the storage is higher as the archiving place among the plural backup data storages according to the degree of importance of data in the storage. Information about the backup data may be related as attribute information to the backup data, and recorded. The computer readable recording medium recorded thereon the backup controlling program may make the computer function as a restoration processing unit for restoring the backup data stored in the backup data storage onto an arbitrary storage. The restoration processing unit may restore at least one set of the backup data selected among plural sets of the backup data onto the arbitrary storage. The backup system, the backup controlling apparatus, the backup data managing method and the computer readable recording medium recorded thereon the backup controlling program according to this invention provide the following effects and advantages. (1) A backup data storage physically away from an area in which the storage is located is selectively determined as an archiving place among a plurality of backup data storages on the basis of the area in which the storage is located, and backup data is archived in the backup data storage determined as the archiving place. Accordingly, even when the storage of an information processing apparatus is damaged or lost due to disaster caused by an earthquake, flood or the like, hard disk failure or virus infection, one of various accidents such as abnormality of the operation caused by installation of a driver for connecting a new peripheral equipment or application software and the like, it is possible to diminish the possibility that the backup data storage archiving the backup data is simultaneously damaged, thereby to improve the security level of the data. Even when data in the information processing apparatus or the storage of the user is lost due to disaster such as an earthquake, fire or the like, the backup data archived in the backup storage can be restored, and contents of the storage can be restored to a state nearest to the state before the abnormality occurs, quickly and certainly, by accessing to the backup data storage over a communication line after the information processing apparatus is restored. It is possible to configure such system with the minimum facility investment. (2) An area in which the storage is located is determined, and a backup data storage physically away from the storage is selectively determined as the archiving place among a plurality of backup data storages on the basis of the determined area in which the storage is located. Accordingly, it is possible to archive the backup data in a backup data storage physically away from the storage, readily and certainly. This is very convenient. (3) The user can selectively designate a specific backup data storage among a plurality of backup data storages by means of the information processing means. Accordingly, it is possible to set an archiving place according to the intension of the user. This is very convenient. (4) Information about backup data is inputted as attribute information, and the inputted attribute information is related to the backup data and recorded in the backup data storage. Accordingly, it becomes easy to discriminate each backup data. This is very helpful when the backup data is restored onto the storage, for example. When various kinds of data in an information processing apparatus is backed up before a work which may cause a change in the system environments of the information processing apparatus such as installation of application software, addition of new hardware or the like, it is possible for the user to easily know the features of prepared backup data (medium) and the system at that time, for example. Additionally, each user does not need to manage the backup data, thus the burden on the user required to manage the backup data can be decreased. (5) Data is partly extracted from data in the storage to prepare the backup data, and the backup data is archived in the backup data storage. When this backup data is restored onto the backup data storage, the user selects at least one set of backup data among plural sets of backup data, and restores the data. Accordingly, it is possible to readily configure a storage having a data structure that the user desires. This is very convenient. | 20050121 | 20090526 | 20050609 | 94805.0 | 0 | LEWIS, CHERYL RENEA | BACKUP SYSTEM, BACKUP CONTROLLING APPARATUS, BACKUP DATA MANAGING METHOD AND A COMPUTER READABLE RECORDING MEDIUM RECORDED THEREON BACKUP CONTROLLING PROGRAM | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,115 | ACCEPTED | Pneumatically operated fastener driving tool | A pneumatically operated fastener driving tool capable of reducing a time period from operation timing of a trigger to downward movement of a driver blade for fastener driving, and reducing a time period from the release timing of the trigger to a timing at which respective components are returned to their initial positions for a subsequent nail driving. As components a main valve and a trigger valve is provided. The main valve is movable within a main valve chamber connected to a main valve control channel. The trigger valve selectively provides fluid communication between the accumulator and a main valve chamber through the main valve control channel and between the main valve chamber and the atmosphere through the main valve control channel. A ratio of cross-sectional area of the main valve control channel to an internal volume of the main valve chamber is defined to a specified ratio. | 1. A fastener driving tool comprising: a frame defining therein an accumulator that accumulates a compressed air; a cylinder disposed within the frame; a piston reciprocally slidably disposed within the cylinder, a piston upper chamber being defined by an inner peripheral surface of the cylinder and an upper surface of the piston; a main valve which alternately opens and blocks a fluid communication between the piston upper chamber and the accumulator; a main valve chamber section defining therein a main valve chamber in which the main valve is movably disposed, the main valve chamber providing a maximum internal volume; a trigger valve which alternately opens and blocks a fluid communication from the accumulator to the main valve chamber, and a fluid communication from the main valve chamber to an atmosphere; and a main valve control channel section defining therein a main valve control channel that provides a fluid connection between the main valve chamber and the trigger valve, the main valve control channel having a cross-sectional area, a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel being not more than 1.0. 2. The fastener driving tool as claimed in claim 1, further comprising: a push lever in pressure contact with a workpiece; and a trigger functioning as an operation input member; and wherein the main valve is reciprocably movably provided in the main valve chamber for alternately providing a fluid communication between the piston upper chamber and the accumulator and between the piston upper chamber and the atmosphere; and wherein the trigger valve comprises: a trigger valve exterior frame to which the main valve control channel is fluidly connected; a valve piston reciprocally slidably disposed within the trigger valve exterior frame and having one end exposed to the accumulator and another end, the valve piston being movable between a top dead center and a bottom dead center, a main valve intake channel being defined between the valve piston and the trigger valve exterior frame for providing fluid connection between the accumulator and the main valve control channel when the valve piston is moved to the upper dead center, and an air discharge channel being defined between the valve piston and the trigger valve exterior frame for providing fluid connection between the main valve control channel and the atmosphere when the valve piston is moved to the bottom dead center, a main valve intake channel and the air discharge channel being alternately opened; and a plunger movable in an axial direction thereof between its top dead center and its bottom dead center and extending through the valve piston and the trigger valve exterior frame, a trigger valve chamber being defined by the trigger valve exterior frame, the another end of the valve piston and the plunger, the air discharge channel having a cross-sectional area not less than the cross-sectional area of the main valve control channel. 3. The fastener driving tool as claimed in claim 2, wherein the main valve intake channel has a cross-sectional area, a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve intake channel being not more than 1.0. 4. The fastener driving tool as claimed in claim 2, wherein the plunger has a first section exposed to the accumulator and extending through the valve piston, and a second section extending through the trigger valve exterior frame, a trigger valve intake channel being defined between the first section and the valve piston for providing a fluid connection between the accumulator and the trigger valve chamber when the plunger is moved to its bottom dead center, and a trigger valve control channel being defined between the second section and the trigger valve exterior frame for providing a fluid connection between the trigger valve chamber and the atmosphere when the plunger is moved to its top dead center, the trigger valve intake channel and the trigger valve control channel being alternately opened. 5. The fastener driving tool as claimed in claim 4, wherein the trigger valve intake channel has a cross-sectional area of not less than 3.00×10−6 m2. 6. The fastener driving tool as claimed in claim 4, wherein the trigger valve intake channel has a cross-sectional area of not less than 3.25×10−6 m2. 7. The fastener driving tool as claimed in claim 4, wherein the trigger valve intake channel has a cross-sectional area of not less than 2.75×10−6 m2. 8. The fastener driving tool as claimed in claim 2, wherein a value obtained from dividing a maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.20. 9. The fastener driving tool as claimed in claim 8, wherein a value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.15. 10. The fastener driving tool as claimed in claim 9, wherein a value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.10. 11. The fastener driving tool as claimed in claim 2, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.8, and wherein a value obtained from dividing the maximum internal volume of the main valve chamber by a cross-sectional area of the main valve intake channel is not more than 0.8. 12. The fastener driving tool as claimed in claim 2, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.6, and wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve intake channel is not more than 0.6. 13. The fastener driving tool as claimed in claim 2, wherein the main valve control channel has a curving portion along its path, the curving portion being composed of one of a continouous arcuate portion and discontinuous two bending portions. 14. The fastener driving tool as claimed in claim 13, wherein the two bending portions provide bending angles of not less than 100°. 15. The fastener driving tool as claimed in claim 2, wherein a value obtained from dividing the maximum volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.8. 16. The fastener driving tool as claimed in claim 2, wherein a value obtained from dividing the maximum volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.6. 17. The fastener driving tool as claimed in claim 1, further comprising: a push lever in pressure contact with a workpiece; and a trigger functioning as an operation input member; and wherein the main valve is reciprocably movably provided in the main valve chamber for alternately providing a fluid communication between the piston upper chamber and the accumulator and between the piston upper chamber and the atmosphere; and wherein the trigger valve comprises: a trigger valve frame to which the main valve control channel is fluidly connected, the trigger valve frame having a first through hole serving as a main valve intake channel and exposed to the accumulator and a second through hole; and a plunger movable in an axial direction thereof between its top dead center and its bottom dead center relative to the trigger valve frame, the plunger having a first section closing the first through hole when the plunger is moved to its upper dead center for closing the main valve intake channel to shut off fluid communication between the accumulator and the main valve control channel and opening the main valve intake channel to provide communication between the accumulator and the main valve control channel, the plunger also having a second section extending through the second trough hole, an air discharge channel being defined between the second through hole and the second section, the air discharge channel being opened when the plunger is moved to its top dead center to provide fluid communication between the main valve control channel and the atmosphere and being closed when the plunger is moved to its bottom dead center, the main valve intake channel and the air discharge channel being alternately opened by the movement of the plunger. 18. The fastener driving tool as claimed in claim 17, wherein the main valve intake channel has a cross-sectional area, a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve intake channel being not more than 1.0. 19. The fastener driving tool as claimed in claim 18, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.8, and wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve intake channel is not more than 0.8. 20. The fastener driving tool as claimed in claim 18, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.6, and wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve intake channel is not more than 0.6. 21. The fastener driving tool as claimed in claim 17, wherein the main valve control channel has a curving portion along its path, the curving portion being composed of one of a continouous arcuate portion and discontinuous two bending portions. 22. The fastener driving tool as claimed in claim 21, wherein the two bending portions provide bending angles of not less than 100°. 23. The fastener driving tool as claimed in claim 17, wherein the air discharge channel has a cross-sectional area equal to or greater than that of the main valve control channel. 24. The fastener driving tool as claimed in claim 17, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.8. 25. The fastener driving tool as claimed in claim 17, wherein a value obtained from dividing the maximum internal volume of the main valve chamber by the cross-sectional area of the main valve control channel is not more than 0.6. 26. A fastener driving tool comprising: a frame defining therein an accumulator for accumulating a compressed air; a cylinder disposed within the frame; a piston reciprocally slidably disposed within the cylinder, a piston upper chamber being defined by the frame, an inner peripheral surface of the cylinder and an upper surface of the piston; a trigger functioning as an operation input member; a trigger valve alternately opening and blocking a fluid communication between the piston upper chamber and the accumulator and a fluid communication between the piston upper chamber and an atmosphere, the trigger valve comprising: a trigger valve exterior frame in fluid communication with the piston upper chamber and formed with a through hole; a valve piston reciprocably slidably disposed in the trigger valve exterior frame, the valve piston being movable between its top dead center where piston upper chamber is communicated with the atmosphere and its bottom dead center where the piston upper chamber is communicated with the accumulator, the valve piston having a first section exposed to the accumulator and formed with a trigger valve intake channel opened to the accumulator and a second section in sliding contact with the trigger valve exterior frame, a trigger valve chamber being defined by the second section and the trigger valve exterior frame, and providing a maximum internal volume; and a plunger movable between its top dead center and its bottom dead center and having a first portion associated with the valve piston and a second portion associated with the through hole, a trigger valve control channel being formed between the second portion and the through hole and having a cross-sectional area, the trigger valve control channel being opened when the plunger is moved to its top dead center, a value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel being not more than 0.20. 27. The fastener driving tool as claimed in claim 26, wherein the value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.15. 28. The fastener driving tool as claimed in claim 26, wherein the value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.1. 29. A fastener driving tool comprising: a frame defining therein an accumulator for accumulating a compressed air; a cylinder disposed within the frame; a piston reciprocally slidably disposed within the cylinder, a piston upper chamber being defined by the frame, an inner peripheral surface of the cylinder and an upper surface of the piston; a trigger functioning as an operation input member; a trigger valve alternately opening and blocking a fluid communication between the piston upper chamber and the accumulator and a fluid communication between the piston upper chamber and an atmosphere, the trigger valve comprising: a trigger valve exterior frame in fluid communication with the piston upper chamber and formed with a through hole; a valve piston reciprocably slidably disposed in the trigger valve exterior frame, the valve piston being movable between its top dead center where piston upper chamber is communicated with the atmosphere and its bottom dead center where the piston upper chamber is communicated with the accumulator, the valve piston having a first section exposed to the accumulator and formed with a trigger valve intake channel opened to the accumulator and a second section in sliding contact with the trigger valve exterior frame, a trigger valve chamber being defined by the second section and the trigger valve exterior frame and providing a maximum internal volume; and a plunger movable between its top dead center and its bottom dead center and having a first portion associated with the valve piston and a second portion associated with the through hole, a trigger valve control channel being formed between the second portion and the through hole and having a cross-sectional area, the trigger valve control channel being opened when the plunger is moved to its top dead center, the trigger valve intake channel having a cross-sectional area of not less than 2.75×10−6 m2, and the trigger valve chamber having a maximum internal volume of 4.0×10−7 m3. 30. The fastener driving tool as claimed in claim 29, wherein the trigger valve intake channel has the cross-sectional area of not less than 3.00×10−6 m2. 31. The fastener driving tool as claimed in claim 29, wherein the trigger valve intake channel has the cross-sectional area of not less than 3.25×10−6 m2. | BACKGROUND OF THE INVENTION The present invention relates to a fastener driving tool such as a nail gun driven by compressed air, and more particularly, to such fastener driving tool improving drive response and decreasing air consumption. Heretofore, fastener driving tools such as nail guns have existed which drive fasteners such as nails or staples using compressed air as the power source. In such fastener driving tools, compressed air is supplied to a piston upper chamber defined by an inner surface of a cylinder and a piston for rapidly displacing the piston to perform nailing. Compressed air is supplied from an external source and temporarily stored in an accumulator formed within a frame of the nail gun. The accumulator and the piston upper chamber are connected by a channel, but one or more valves which are switched between open and shut-off positions are provided along this channel. These valves are designed to open or shut-off the channel by supplying or expelling compressed air in valve chambers constituted by the spaces each adjacent to each valve. Typically the structure is such that a first valve is activated as a result of external operation of a trigger or the like, and this operation allows a downstream passage to be communicated with or to be shut-off from the first valve. Thus, a downstream valve chamber is brought into communication with or shutting-off from the upstream passage, thereby sequentially activating or deactivating the downstream valves. In addition, a time period starting from completion of the nail driving operation to restoration to an initial state for the next nailing operation is dependent upon the circulation speed of the compressed air in the fastener driving tool after the trigger is released, and the movement speed of the valves in proportion to this circulation speed. That is, the time period is dependent on the shut-off speed for shutting off the piston upper chamber in the cylinder from the accumulator by a valve caused by, after releasing the trigger or the like, circulation of the compressed air through the channel in the fastener driving tool as a result of the returning motion of a plunger which had been pressed by this trigger. In a conventional fastener driving tools as disclosed in Japanese Patent Publication No.S58-50833, valve activation is performed sequentially from valves whose valve chamber volume is small to valves with large valve chamber in order to stabilize operation of the valves irrespective of the speed with which the trigger is pulled. Since with this structure the valves are sequentially activated by compressed air, a time period starting from pulling the trigger and/or pushing operation of a push lever against a workpiece to a start of the nailing driving motion is highly dependent upon the time required to sequentially activate the valves. In order to reduce this time period and increase response, Japanese Patent Publication No. H7-112674 discloses a nail gun, in which a main valve is divided into first and second valves, so that kinetic energy of the first valve is utilized to improve the operating speed of the second valve. With this structure in which the main valve is divided into two valves, only the time period from when the second valve begins to move until it moves to maximum displacement is reduced. The time period from both pulling the trigger and pushing the push lever onto the workpiece to the operation timing of the first valve is still not reduced. In addition, since only the time period from when the second valve begins to move until it moves to maximum displacement is reduced, it was only possible to reduce the time period from when the trigger is pulled until nailing is performed. Consequently, a time period from the completion timing of the nail driving operation to the start timing of the next nail driving operation cannot be reduced when continuous nailing is performed. That is, a response cannot be improved. Laid-open Japanese Patent Application Kokai No. H11-33930 discloses a structure in which, an internal volume of a main valve chamber for accommodating therein a main valve is increased. With this arrangement, air damping behavior due to compression of the main valve chamber does not occur when the main valve rises and is contained in the main valve chamber. With this structure in which the volume of the main valve chamber is increased, the amount of compressed air accumulated in the main valve chamber increases. For this reason, the time period for discharging the compressed air out of the main valve chamber is increased, which degrades the response. Laid-open Japanese Patent Application Kokai No. H5-138548 discloses communication of a piston lower chamber with a trigger valve chamber. The movement speed of a valve piston and a main valve are increased as a result of the pressure which is generated from the movement of the piston. With this structure in which the piston lower chamber and trigger valve chamber are connected, at the instant that the piston passes through the one-way valve disposed at an intermediate region of the cylinder, compressed air flows into the trigger valve chamber and closes the main valve. Therefore, the nailing force was reduced. Moreover, extremely complicated structure results. Another conventional fastener driving tool has been proposed. The tool includes a trigger valve and main valve. A trigger valve exterior frame internally defines a trigger valve chamber. The trigger valve includes a plunger extending through the trigger valve exterior frame and the trigger valve chamber and slidably movable as a result of the movement of the trigger and the abutment of the push lever against the workpiece. The movement of the plunger selectively shuts off a fluid communication between the accumulator and the trigger valve chamber and between the trigger valve chamber and an atmosphere. However, the resultant arrangement cannot provide high response for discharging compressed air from the main valve. Still another conventional fastener driving tool is proposed in which a main valve is not provided, but a trigger valve is additionally equipped with a valve piston. The valve piston is reciprocably slidably disposed in a trigger valve exterior frame, and has one side in the sliding direction facing the accumulator. The valve piston alternately opens and blocks a channel from the piston upper chamber connected to the trigger valve exterior frame to the accumulator and a channel from the piston upper chamber to the atmosphere. With this fastener driving tool, the displacement of the valve piston serves to select the air channel and control the nailing of the fastener. However, the speed of the displacement of the valve piston is low, and the delay in the displacement of this valve piston can cause other control to be delayed as well. Consequently, the problem arises that the time lag from when the operator begins the nailing operation until the fastener is actually driven becomes large, response becomes poor to lower workability. In addition, the problem arises that when many fasteners are to be driven in a short period of time, the aforementioned time lag makes continuous nailing difficult to perform. In addition, with the conventional fastener driving tools, after nailing, in order to return the piston to the pre-nailing position, the piston upper chamber and the atmosphere are communicated with each other for releasing the compressed to the atmosphere, while the valve is closed for preventing the compressed air from flowing from the accumulator into the piston upper chamber. However, during the period from when the valve begins to close until it is completely closed, the accumulator and the piston upper chamber are communicated with each other, and the piston upper chamber and the atmosphere are also communicated with each other. Accordingly, the compressed air in the accumulator would in some cases flow unnecessarily into the piston upper chamber and is expelled into the atmosphere. This causes an increase in air consumption, which consequently requires a high-performance compressor or the like to produce compressed air. SUMMARY OF THE INVENTION It is therefore an object of the present invention is to provide a fastener driving tool improving the response and continuous shots or nailing performance in nailing work, yet reducing the consumption of compressed air. This and other objects of the present invention will be attained by A fastener driving tool including a frame, a cylinder, a piston, a main valve, a main valve chamber section, a trigger valve, and a main valve control channel section. The frame defines therein an accumulator that accumulates a compressed air. The cylinder is disposed within the frame. The piston is reciprocally slidably disposed within the cylinder. A piston upper chamber is defined by an inner peripheral surface of the cylinder and an upper surface of the piston. The main valve alternately opens and blocks a fluid communication between the piston upper chamber and the accumulator. The main valve chamber section defines therein a main valve chamber in which the main valve is movably disposed. The main valve chamber provides a maximum internal volume. The trigger valve alternately opens and blocks a fluid communication from the accumulator to the main valve chamber, and a fluid communication from the main valve chamber to an atmosphere. The main valve control channel section defines therein a main valve control channel that provides a fluid connection between the main valve chamber and the trigger valve. A value obtained from dividing the maximum internal volume of the main valve chamber by a cross-sectional area of the main valve control channel being not more than 1.0. In another aspect of the invention, there is provided a fastener driving tool including a frame, a cylinder, a piston, a trigger, and a trigger valve provided with a trigger valve exterior frame, a valve piston and a plunger. The frame defines therein an accumulator for accumulating a compressed air. The cylinder is disposed within the frame. The piston is reciprocally slidably disposed within the cylinder. A piston upper chamber is defined by the frame, an inner peripheral surface of the cylinder and an upper surface of the piston. The trigger functions as an operation input member. A trigger valve alternately opens and blocks a fluid communication between the piston upper chamber and the accumulator and a fluid communication between the piston upper chamber and an atmosphere. The trigger valve exterior frame is in fluid communication with the piston upper chamber and is formed with a through hole. The valve piston is reciprocably slidably disposed in the trigger valve exterior frame. The valve piston is movable between its top dead center where piston upper chamber is communicated with the atmosphere and its bottom dead center where the piston upper chamber is communicated with the accumulator. The valve piston has a first section exposed to the accumulator and formed with a trigger valve intake channel opened to the accumulator and a second section in sliding contact with the trigger valve exterior frame. A trigger valve chamber is defined by the second section and the trigger valve exterior frame and provides a maximum internal volume. The plunger is movable between its top dead center and its bottom dead center and has a first portion associated with the valve piston and a second portion associated with the through hole. A trigger valve control channel is formed between the second portion and the through hole and has a cross-sectional area. The trigger valve control channel is opened when the plunger is moved to its top dead center. A value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.20. Further, in the fastener driving tool including the frame, the cylinder, the piston, the trigger, and the trigger valve provided with the trigger valve exterior frame, the valve piston and the plunger, the trigger valve intake channel has a cross-sectional area of not less than 2.75×10−6 m2, and the trigger valve chamber has a maximum internal volume of 4.0×10−7 m3. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings; FIG. 1 is a cross-sectional view of the fastener driving tool according to the first embodiment of the present invention; FIG. 2 is an enlarged cross-sectional view of a trigger valve in the fastener driving tool according to the first embodiment; FIG. 3 is a partial cross-sectional view particularly showing a main valve in the fastener driving tool according to the first embodiment; FIG. 4 is an enlarged cross-sectional view particularly showing the trigger valve in the fastener driving tool according to the first embodiment, with a plunger having been pushed upward; FIG. 5 is an enlarged cross-sectional view particularly showing the trigger valve in the fastener driving tool according to the first embodiment, with the plunger having been pushed upward and a valve piston then having moved to its bottom dead center; FIG. 6 is a graph showing the relationship between a valve piston displacement time (T2) and a ratio of volume (V2) of trigger valve chamber to a cross-sectional area (S2) of a trigger valve control channel in the fastener driving tool according to the first embodiment; FIG. 7 is a graph showing the relationship between a time period (T1) until a main valve returns to its initial position after a plunger returns to its initial position and a cross-sectional area (St) of a trigger valve intake channel in the fastener driving tool according to the first embodiment; FIG. 8 is a partial cross-sectional view particularly showing the main valve in the fastener driving tool according to the first embodiment, with the main valve having moved to the top dead center; FIG. 9 is a graph showing the relationship between a main valve displacement time (T1) and a ratio of volume (V1) of main valve chamber to a cross-sectional area (S1) of a main valve control channel in the fastener driving tool according to the first embodiment; FIG. 10 is a graph in which a solid line curves shows the relationship between the main valve displacement time (T1) and the ratio of volume (V1) of main valve chamber to the cross-sectional area (S1) of the main valve control channel, and a broken line curves shows the relationship between air consumption amount (NL) and the ratio (V1/S1) or (V1/Sm) in which “Sm” designates a main intake control channel according to the first embodiment; FIG. 11 is an enlarged cross-sectional view particularly showing the trigger valve in the fastener driving tool according to the first embodiment, with the valve piston having moved to the bottom dead center and the plunger then having returned to its original position; FIG. 12 is a partial cross-sectional view particularly showing a main valve according to a modification to the first embodiment; FIG. 13 is a cross-sectional view of the fastener driving tool according to a second embodiment of the present invention; FIG. 14 is an enlarged cross-sectional view particularly showing a trigger valve in the fastener driving tool according to the second embodiment; FIG. 15 is an enlarged cross-sectional view particularly showing the trigger valve in the fastener driving tool according to the first embodiment, with a plunger having been pushed upward; FIG. 16 is a cross-sectional view of the fastener driving tool according to the second embodiment, with a main valve having moved to the top dead center; FIG. 17 is a cross-sectional view of a fastener driving tool according to a third embodiment of the present invention; FIG. 18 is an enlarged cross-sectional view particularly showing a trigger valve in the fastener driving tool according to the third embodiment; FIG. 19 is an enlarged cross-sectional view particularly showing the trigger valve in the fastener driving tool according to the third embodiment, with a plunger having been pushed upward; FIG. 20(a) is a graph showing the relationship between time and pressure in a trigger valve chamber 13, a main valve chamber 8, an accumulator 2, a piston upper chamber 4a, and a return chamber 33 in a fastener driving tool according to the first embodiment; FIG. 20(b) is a graph showing the relationship between the time and a displacement of a main valve according to the first embodiment; FIG. 20(c) is a graph showing the relationship between the time and a displacement of a valve piston according to the first embodiment; FIG. 20(d) is a graph showing the relationship between the time and a displacement of a piston according to the first embodiment; FIG. 21(a) is a graph showing the relationship between time and pressure in a trigger valve chamber 13′, a main valve chamber 8′, an accumulator 2′, a piston upper chamber 4a′, and a return chamber 33′ in a comparative fastener driving tool; FIG. 20(b) is a graph showing the relationship between the time and a displacement of a main valve according to the comparative fastener driving tool; FIG. 20(c) is a graph showing the relationship between the time and a displacement of a valve piston according to the comparative fastener driving tool; FIG. 20(d) is a graph showing the relationship between the time and a displacement of a piston according to the comparative fastener driving tool; FIG. 22(a) is a graph showing the relationship between time and pressure in a trigger valve chamber 13, a main valve chamber 8, an accumulator 2, a piston upper chamber 4a, and a return chamber 33 in the fastener driving tool according to the first embodiment; FIG. 22(b) is a graph showing the relationship between the time and a displacement of a main valve according to the first embodiment; FIG. 22(c) is a graph showing the relationship between the time and a displacement of a valve piston according to the first embodiment; FIG. 22(d) is a graph showing the relationship between the time and a displacement of a piston according to the first embodiment; FIG. 22(e) is a graph showing the relationship between the time and a displacement of a tool itself according to the first embodiment; FIG. 23(a) is a graph showing the relationship between time and pressure in a trigger valve chamber 13′, a main valve chamber 8′, an accumulator 2′, a piston upper chamber 4a′, and a return chamber 33′ in another comparative fastener driving tool; FIG. 23(b) is a graph showing the relationship between the time and a displacement of a main valve according to the comparative fastener driving tool; FIG. 23(c) is a graph showing the relationship between the time and a displacement of a valve piston according to the comparative fastener driving tool; FIG. 23(d) is a graph showing the relationship between the time and a displacement of a piston according to the comparative fastener driving tool; and FIG. 23(e) is a graph showing the relationship between the time and a displacement of a tool itself according to the comparative fastener driving tool. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fastener driving tool according to a first embodiment of the present invention will be described with reference to FIGS. 1 through 11. The fastener driving tool shown in FIG. 1 is a nail gun 1 which uses compressed air as the power source. The nail gun 1 includes a frame 60, a handle 60A disposed at one side of the frame 60, and a nose 41 disposed at a lower end of the frame 60. These frame 60, handle 60A and nose 41 are provided as an integral unit to form an outer frame. An accumulator 2 is formed within the handle 60A and frame 60 for accumulating therein a compressed air delivered from a compressor (not shown) through an air hose (not shown). A cylinder 3 is provided within the frame 60, and a piston 4a is reciprocally movably provided and slidably within the cylinder 3. A driver blade 4b is provided integrally with the piston 4a, and has a free end 4c for abutting against the fastener 5 for driving. A return chamber 33 which accumulates therein a compressed air to return the driver blade 4b to its upper dead center is provided around the lower outer peripheral surface of the cylinder 3. A one-way valve 34 is provided in an axially intermediate portion of the cylinder 3. An air channel 35 is formed in the cylinder 3 for allowing the compressed air to flow in only one direction, i.e., from inside the cylinder 3 to the return air chamber 33, outside the cylinder 3. In addition, an air channel 36 is formed at a lower portion of the cylinder 3 for providing continuous communication between the cylinder 3 and the return chamber 33. In addition, a piston bumper 37 is provided at the bottom of the cylinder 3 for absorbing excess energy from the driver blade 4b after nailing the fastener 5. An operating portion 38 is provided at the base of the handle 60A. This operating portion 38 includes a trigger 39 operated by the user, an arm plate 48 which is attached pivotally movably to the trigger 39, and a push lever 42 which projects from the bottom of the nose 41 and extends to the vicinity of the arm plate 48. The push lever 42 is movable along the nose 41 and is biased away from the frame 60. In addition, a trigger valve 6 is provided at the base of the handle 60A and in confrontation with the trigger 39. As is well known in the art, the structure is such that, when both the trigger 39 is pulled and the push lever 42 is pressed against the workpiece, a plunger 7 on the trigger valve 6 is pushed upward, as shown in FIG. 2, by a linking mechanism of the arm plate 48 and the trigger 39. A nail injection section 43 provided in conjunction with the nose 41 includes a magazine 44 and a feed mechanism 45. The magazine 44 is loaded with fasteners 5 arrayed side by side. The feed mechanism 45 is adapted for successively feeding fasteners 5 loaded in the magazine 44 to an injection opening 46 at the nose 41. The trigger valve 6 shown in FIG. 1 and FIG. 2 mainly includes an outer valve bush 10, an inner valve bush 11, a valve piston 9, a plunger 7, and a spring 12. The outer valve bush 10 and inner valve bush 11 are fixed to the frame 60 to form a trigger valve exterior frame which constitutes an outer wall of the trigger valve. The valve piston 9 is provided reciprocably slidably within the outer valve bush 10 and inner valve bush 11. The valve piston 9 and the outer valve bush 10 are formed with through holes, so that the plunger 7 is provided reciprocably slidably with respect to the through holes. The plunger 7 has a bottom end in contact with the arm plate 48. The spring 12 is interposed between the valve piston 9 and the plunger 7 for biasing the valve piston 9 and the plunger 7 in opposite directions, i.e., for biasing the valve piston 9 upward while biasing the plunger 7 downward. The trigger valve 6 is fluidly connected to a main valve control channel 40, which is a cylindrical tube extending from a main valve chamber 8 described later. Specifically, the main valve control channel 40 is fluidly connected to a space between the outer valve bush 10 and inner valve bush 11, and opens into the trigger valve 6. This main valve control channel 40 is configured such that its cross-sectional area S1 is 3.2×10−5 (m2) . In addition, O-rings 17 and 25 are fitted on the inner valve bush 11. The O-ring 17 is adapted for continually blocking fluid connection between the accumulator 2 and the main valve control channel 40. The O-ring 25 is adapted for continually blocking fluid connection between the main valve control channel 40 and an atmosphere. One side of the valve piston 9 in the sliding direction faces the accumulator 2, and the inner valve bush 11 has an accumulator side and an atmospheric side. An outer diameter at an accumulator side of the valve piston 9 is smaller than an inner diameter of the accumulator side of the inner valve bush 11 to define therebeween a main valve intake channel 20. Further, an outer diameter at an atmospheric side of the valve piston 9 is smaller than an inner diameter of the atmospheric side of the inner valve bush 11 to define therebetween an air channel 22. Further, an O-ring 21 and an O-ring 23 are disposed at the accumulator side and atmospheric side of the valve piston 9, respectively, for selectively blocking the respective channels 20 and 22. Consequently, the main valve intake channel 20 passes between the valve piston 9 and the inner valve bush 11 to provide fluid communication between the accumulator 2 and the main valve control channel 40 when the O-ring 21 is out of contact from the inner valve bush 11. Further, the air channel 22 passes between the valve piston 9 and the inner valve bush 11 to provide fluid communication between the main valve control channel 40 and the atmosphere when the O-ring 22 is out of contact from the inner valve bush 11. This air channel 22 is formed such that its cross-sectional area extending perpendicular to a flowing direction is larger than that of the main valve channel 40. As a result, the flow resistance at the air channel 22 will be lower than that of the main valve channel 40. The main valve intake channel 20 and air channel 22 are alternately opened and blocked due to the vertical sliding of the valve piston 9. In addition, the main intake control channel 20 is formed such that its cross-sectional area Sm is 3.2×10−5 (m2). A trigger valve chamber 13 is defined by another side (lower side) of the valve piston 9 in the sliding direction and the outer valve bush 10. This trigger valve chamber 13 has an internal volume variable due to the sliding movement of the valve piston 9, and is formed such that a maximum internal volume V2 defined when the valve piston 9 is at the top dead center is 4.0×10−7 (m3). In addition, an O-ring 24 is fitted onto the valve piston 9 for continually blocking the fluid connection between the air channel 22 and the trigger valve chamber 13. The plunger 7 extends through the trigger valve chamber 13, and a top end faces the accumulator 2. The valve piston 9 has first and second sliding regions relative to the valve piston 9 and the outer valve bush 10, and O-ring grooves are formed at the respective sliding regions for installing therein an O-ring 15 and an O-ring 18 for maintaining hermetic seal. An outer diameter of the first sliding region is smaller than an inner diameter of the valve piston 9 for defining therebetween a trigger valve intake channel 14, and an outer diameter of the second sliding region is smaller than an inner diameter of the outer valve bush 10 for defining therebetween a trigger valve control channel 16. Consequently, the trigger valve intake channel 14 passes between the plunger 7 and the valve piston 9 for providing fluid communication from the accumulator 2 to the trigger valve chamber 13 when the O-ring 15 is out of contact from the valve piston 9. Further, the trigger valve control channel 16 passes between the plunger 7 and the outer valve bush 10 to provide fluid communication from the trigger valve chamber 13 to the atmosphere when the O-ring 18 is out of contact from the outer valve bush 10. The trigger valve intake channel 14 and trigger valve control channel 16 are alternately opened and blocked in accordance with the sliding motion of the plunger 7. The trigger valve intake channel 14 is formed such that its cross-sectional area St is 2.75×10−6 (m2). Further, the trigger valve control channel 16 is formed such that its cross-sectional area S2 is 1.98×10−6 (m2). As a result, the value obtained from dividing the volume of the trigger valve chamber 13 by the cross-sectional area of the trigger valve control channel 16 is V2/S2=0.2. The structure of the trigger valve 6 is such that, when the valve piston 9 is positioned toward the top dead center (for example FIG. 2), the main valve intake channel 20 is opened so that the accumulator 2 and the main valve control channel 40 are communicated with each other, while air channel 22 is closed by the O-ring 23 so that fluid communication between the main valve control channel 40 and the atmosphere is blocked. In addition, when the valve piston 9 is positioned toward the bottom dead center (for example FIG. 5), the main valve intake channel 20 is closed by the O-ring 21, so that fluid communication between the main valve control channel 40 and the accumulator 2 is blocked, while air channel 22 is opened so that and the main valve control channel 40 and the atmosphere are communicated with each other. When the plunger 7 is positioned toward the top dead center (FIG. 5), the trigger valve control channel 16 is opened so that the trigger valve chamber 13 is communicated with the atmosphere, while the trigger valve intake channel 14 is closed by the O-ring 15 so that fluid communication between the accumulator 2 and the trigger valve chamber 13 is blocked. In addition, when the plunger 7 is positioned toward the bottom dead center (FIG. 2), the trigger valve control channel 16 is closed by the O-ring 18, so that fluid communication between the trigger valve chamber 13 and the atmosphere is blocked, while the trigger valve intake channel 14 is opened so that the accumulator 2 and the trigger valve chamber 13 are communicated with each other. A main valve section 26 is provided immediately above and around the outer peripheral surface of the cylinder 3 as shown in FIGS. 1 and 3. The main valve section 26 generally includes a main valve 19, a main valve rubber 27, a main valve spring 28, and an exhaust rubber 30. The main valve rubber 27 is fitted to the top end of the cylinder 3. The main valve spring 28 is adapted for biasing the main valve 19 toward its bottom dead center. The exhaust rubber 30 is placed above the cylinder 3. An air discharge passage 29 is formed above the cylinder 3 for discharging the compressed air in the piston upper chamber above the piston 4a. The exhaust rubber 30 is adapted for shutting off the air discharge passage 29 when the main valve 19 is coming into contact with the exhaust rubber 30. In addition, the upper end of the frame 60 is formed with an exhaust hole 49 to which the air passage 29 is connected. Thus, the compressed air in the piston upper chamber can be discharged to the atmosphere. A main valve sectioning region 61 is provided as an upper part of the frame 60. The main valve sectioning region 61 provides a main valve chamber 8 in which the main valve 19 is vertically slidably movably provided. The main valve chamber 8 is in communication with the main valve control channel 40. The main valve 19 has top and middle portions provided with O-rings 31 and 32, respectively. The O-ring 31 is adapted for continually blocking fluid communication between the main valve chamber 8 and the air channel 29, and the O-ring 32 is adapted for continually blocking fluid communication between the main valve chamber 8 and the accumulator 2. Thus, the main valve chamber 8 is hermetically maintained by these O-rings 31 and 32. The main valve chamber 8 has an internal volume variable in accordance with the vertical movement of the main valve 19, but has a maximum volume V1 of 2.56×10−5 (m3). As a result, the value obtained from dividing the volume V1 of the main valve chamber 8 by the cross-sectional area S1 of the main valve control channel 40 is V1/S1=0.8≦1.0. Likewise, the value obtained from dividing the volume V1 of the main valve chamber 8 by the cross-sectional area Sm of the main valve intake channel 20 is V1/Sm=0.8≦1.0. In addition, the main valve control channel 40 has a curving portion as shown at the location enclosed by a circle in FIG. 3. The curving portion is formed into a gentle arc shape. When the main valve 19 is positioned toward the top dead center, the main valve 19 comes into contact with the exhaust rubber 30 to shut off the air exhaust passage 29, so that fluid communication between the piston upper chamber of the cylinder 3 and the atmosphere is blocked, while the piston upper chamber of the cylinder 3 and the accumulator 2 are communicated with each other. On the other hand, when the main valve 19 is positioned toward the bottom dead center, the main valve 19 comes into contact with the main valve rubber 27 for blocking fluid communication between the piston upper chamber of the cylinder 3 and the accumulator 2, while the main valve 19 separates from the exhaust rubber 30 for opening the air exhaust passage 29, so that the piston upper chamber of the cylinder 3 is communicated with the atmosphere. The nail driving operation will be described. FIG. 1 to FIG. 3 show state in which compressed air from the compressor (not shown) is accumulated in the accumulator 2 through the hose (not shown). In this state, as shown in FIG. 2, the plunger 7 is positioned at the bottom dead center, since the pressure within the accumulator 2 acts on the upper surface of plunger 7, and since biasing force of the spring 12 is imparted on the plunger 7. Since the plunger 7 is positioned at the bottom dead center, the trigger valve intake channel 14 is open to provide fluid communication between the accumulator 2 and the trigger valve chamber 13. At the same time, the trigger valve control channel 16 is closed by the O-ring 18, so the fluid connection between the trigger valve chamber 13 and the atmosphere is blocked. As a result, a part of the compressed air in the accumulator 2 flows through the trigger valve intake channel 14 and into the trigger valve chamber 13, and air in the trigger valve chamber 13 has the same pressure as in the accumulator 2. In this case, because of the biasing force of the spring 12 and the difference in pressure receiving areas of the valve piston 9, the valve piston 9 is positioned at its top dead center. Therefore, the main valve intake channel 20 is open to communicate the accumulator 2 with the main valve control channel 40. At the same time, the air channel 22 is closed by the O-ring 23, so the connection between the main valve control channel 40 and the atmosphere is blocked. As a result, a portion of the compressed air in the accumulator 2 flows into the main valve control channel 40, and air accumulates in the main valve chamber 8 at the same pressure as in the accumulator 2. Since the part of the compressed air in the accumulator 2 flows into the main valve chamber 8, the main valve 19 is positioned at the bottom dead center as shown in FIG. 3 as a result of downward pressing load arising from the difference in pressure receiving areas between the lower peripheral surface 52 and the upper end surface 54 of the main valve 19, along with the biasing force of the main valve spring 28. Since the main valve 19 is positioned at the bottom dead center, the main valve 19 comes into contact with the main valve rubber 27 while separating from the exhaust rubber 30 to open the air discharge passage 29. As a result, the piston upper chamber of the cylinder 3 is brought into communication with the atmosphere. Thus, the piston upper chamber assumes the atmospheric pressure. In addition, the fluid connection between the piston upper chamber of the cylinder 3 and the accumulator 2 is blocked. Thus, compressed air in the accumulator 2 does not flow into the piston upper chamber. As a result, the piston 4a is maintained at its top dead center position. FIG. 4 shows the state where the plunger 7 is pushed up to the top dead center by pulling the trigger 39 and pressing the push lever 42 against the workpiece. Since the plunger 7 is positioned at the top dead center, the O-ring 18 loses its sealing effect, and the trigger valve control channel 16 will be opened. As a result, the trigger valve chamber 13 and the atmosphere are communicated with each other, so the inside of the trigger valve chamber 13 assumes the atmospheric pressure. In addition, the trigger valve intake channel 14 is closed by the O-ring 15 for blocking fluid communication between the accumulator 2 and the trigger valve chamber 13. Thus, compressed air does not any more flow from the accumulator 2 into the trigger valve chamber 13. Since the trigger valve chamber 13 assumes the atmospheric pressure, a difference arises between the pressure imparted to the valve piston 9 at its accumulator side and the pressure imparted to the valve piston 9 in the trigger valve chamber 13. Because of the pressure difference, the valve piston 9 moves to the bottom dead center as shown in FIG. 5. The value obtained from dividing the maximum volume V2 of the trigger valve chamber 13 by the cross-sectional area S2 of the trigger valve control channel 16 is V2/S2=0.2. This value is set smaller than that in conventional fastener driving tools. This is a design concept obtained as a result of recognition of the principle in a tube flow that there is a proportional relationship between the mass rate of flow and the cross-sectional area of the tube. More specifically, it is based on the discovery that, with fastener driving tools which have valve chambers, the time period required for the pressure in these valve chambers to drop to a specific pressure due to the discharge of air decreases in accordance with an increase in the cross-sectional area of the channels used to discharge air with respect to the volume of these valve chambers. FIG. 6 shows the relationship between V2/S2 and the time period T2 from when the pressure inside the trigger valve chamber 13 begins to drop until the valve piston 9 moves to maximum displacement. The smaller V2/S2 is made, the smaller T2 becomes as well. For the value in this first embodiment, V2/S2=0.2, T2 is approximately 0.75 ms. Consequently, the time period required for the pressure in the trigger valve chamber 13 to drop to a specific pressure decreases, and accordingly, time period from when the plunger 7 is pressed until the valve piston 9 moves to maximum displacement can be reduced. As a result, the amount of time from when the trigger 39 and the push lever 42 are operated until the nailing motion occurs due to the displacement of the trigger valve can be further reduced. Incidentally, by making V2/S2=0.15, T2 can be made smaller, and by making V2/S2=0.10, T2 can be made smaller still, and the amount of time until the nailing motion occurs can be shortened. Thus, by setting the maximum volume V2 of the trigger valve chamber 13 and the cross-sectional area S2 of the trigger valve control channel 16 to the aforementioned values, discharge of the compressed air from the trigger valve chamber 13 can be promptly performed, and the time period until the trigger valve chamber 13 assumes the atmospheric pressure can be reduced. Furthermore, since the discharge of air from the trigger valve chamber 13 can be improved when the valve piston 9 is moved to the bottom dead center, a so-called air damper in which the pressure in the trigger valve chamber 13 impedes the movement of the valve piston 9 is not readily formed. Accordingly, the valve piston 9 can be moved immediately from the top dead center to the bottom dead center without being interrupted by the air damper. Incidentally, even though the valve piston 9 is biased toward the top dead center by the spring 12, the valve piston 9 is movable to the bottom dead center by the pressure difference since the biasing force of the spring 12 is set beforehand to be weaker than the force caused by the pressure difference. As shown in FIG. 5, since the valve piston 9 is positioned at the bottom dead center, the main valve intake channel 20 is closed by the O-ring 21 to block fluid communication from the accumulator 2 to the main valve control channel 40. In addition, the O-ring 23 loses its sealing effect to open the air channel 22, so that the main valve control channel 40 is brought into communication with the atmosphere. As a result, the main valve control channel 40 and the main valve chamber 8 assume atmospheric pressure. When the main valve chamber 8 assumes generally the atmospheric pressure, the main valve 19 then moves to the top dead center as shown in FIG. 8 as a result of the upward pressure arising from the difference in pressure receiving areas at the lower outer peripheral surface 52 and at the upper end surface 54 of the main valve 19. When the main valve 19 begins to move toward the top dead center, the accumulator 2 and the piston upper chamber in the cylinder 3 are brought into fluid communication with each other. Thus, because of the pressure imparted to the lower outer peripheral surface 52 as well as to the lower end surface 53 of the main valve 19, the main valve 19 moves rapidly toward the top dead center, and comes into contact with the exhaust rubber 30 to close the air discharge passage 29 whereupon the piston upper chamber is shut off from the atmosphere. In this case, the accumulator 2 is also shut off from the atmosphere. By the movement of the main valve 19 toward its upper dead center, the fluid in the main valve chamber 8 is discharged into the main valve control channel 40. As described above, the value obtained from dividing the maximum volume V1 of the main valve chamber 8 by the cross-sectional area S1 of the main valve control channel 40 is V1/S1=0.8. This value is set smaller than that in the conventional fastener driving tools. This is a design concept which, just as with the design concept described above, was also obtained as a result of recognition of the flow principle that, with fastener driving tools which have valve chambers, the time period required for the pressure in these valve chambers to drop to a specific pressure due to the discharge of air decreases in accordance with an increase in cross-sectional area of the channels used to discharge air with respect to the volume of these valve chambers. FIG. 9 shows the relationship between V1/S1 and the time period T1 from when the pressure in the main valve chamber 8 begins to drop until the main valve 19 moves to maximum displacement. The smaller V1/S1 is made, the smaller T1 becomes as well. For the value in this first embodiment, V1/S1=0.8 at which T1 is approximately 7.0 ms. Consequently, the time period required for the pressure in the main valve chamber 8 to drop to a specific pressure decreases. Accordingly, the time period from when the plunger 7 is pressed as a result of the trigger 39 and the push lever 42 being operated until the main valve 19 moves to maximum displacement can be reduced. As a result, the time period from when the trigger 39 and the push lever 42 are operated until the nailing motion occurs because of the displacement of the main valve 19 can be reduced. Incidentally, if V1/S1 is set to 1.0, T1 becomes 7.5 ms, which is sufficiently small. If V1/S1 is set to 0.6, T1 can be made even smaller, about 5.0 ms. Thus, time period until the nailing motion occurs can be further shortened. In the first embodiment, a bending section is provided in the main valve control channel 40. However, the bending section does not cause significant flow path resistance, since the bending section is configured into an gentle arcuate shape. Consequently, there is no obstruction in the flow of air in the main valve control channel 40. Furthermore, as described above, the air in the main valve chamber 8 passes from the main valve control channel 40 through air channel 22 of the trigger valve 6 and is discharged into the atmosphere. In this case, since cross-sectional area of the air channel 22 is larger than that of the main valve control channel 40 in terms of air flowing passage, the air channel 22 does not prevent the air from flowing from the main valve chamber 8 into the atmosphere. Consequently, the time period from when the trigger 39 and the push lever are operated until the nailing motion occurs can be shortened. Thus, by setting the maximum volume of the main valve chamber 8 and the cross-sectional area of the main valve control channel 40 to the aforementioned values, the compressed air in the main valve chamber 8 will escape more quickly, so that the time period until the main valve chamber 8 assumes the atmospheric pressure can be reduced. Furthermore, a so-called air damper in the main valve chamber 8 is not readily formed because of the improvement on the shape of the main valve control channel 40 and improvement on passing of air through the air channel 22. Accordingly, the escape of air from the main valve chamber 8 can be improved even when the main valve 19 rises to the top dead center. Consequently, the main valve 19 can be moved immediately from the bottom dead center to the top dead center. By the movement of the main valve 19 from its bottom dead center to the top dead center, the compressed air rapidly flows from the accumulator 2 into the piston upper chamber, thereby rapidly moving the piston 4a toward its bottom dead center. Thus, the fastener 5 is driven by the tip end 4c of the driver blade 4b connected to the piston 4a. The air in the underside of the piston 4a in the cylinder 3 flows through air channel 36 into the return air chamber 33. Further, a portion of the compressed air in the piston upper chamber also flows through the air channel 35 into the return air chamber 33, after the piston 4a is moved past the air channel 35. FIG. 11 shows the state where the plunger 7 has just returned to the bottom dead center after release of the trigger 39 or after the pressing of the push lever 42 against the workpiece is stopped. The plunger 7 has moved to the bottom dead center because of the pressure applied to the upper end face of the plunger 7 from the accumulator 2 and the biasing force of the spring 12. By the movement of the plunger 7 to the bottom dead center, the trigger valve control channel 16 is closed by the O-ring 18, while the O-ring 15 loses its sealing effect. Thus, the compressed air in the accumulator 2 flows through the trigger valve intake channel 14 into the trigger valve chamber 13. In this case, as described above, the cross-sectional area St of the trigger valve intake channel 14 is set to 2.75×10−6 (m2), which is relatively larger than that of the conventional tool. This is due to a design concept obtained as a result of recognition of the tube flow principle that there is a proportional relationship between the mass rate of flow and the cross-sectional area of the tube. More specifically, it is based on the discovery that, with fastener driving tools having valve chambers, the time period required for the pressure in these valve chambers to be increased to a specific pressure due to introduction of the compressed air thereinto is reduced in accordance with an increase in the cross-sectional area of the channels used for the introduction of the compressed air with respect to the volume of these valve chambers. FIG. 7 shows the relationship (solid line curve) between the cross-sectional area (St) of the trigger valve intake channel 14, and the time period T1 until the main valve returns to the initial position. FIG. 7 also shows the relationship (broken line curve) between the cross-sectional area (St) and air consumption volume NL. As the cross-sectional area St decreases, the main valve return time period can be reduced and the air consumption volume can be decreased. These curves T1 and NL appear as convex functions toward the lower direction. Therefore, the reducing or decreasing effects are not greatly exhibited at the greater range of the cross-sectional area. Taking the phenomena into consideration, the specific value was determined experimentally to be 2.75×10−6 (m2). As a result, the time period required for the pressure in the trigger valve chamber 13 to rise to a specific pressure due to the inflow of compressed air is reduced. Thus, the time period from when the pressing force on the plunger 7 ceases until the valve piston 9 returns to the pre-nailing position can be shortened. By the introduction of the compressed air into the trigger valve chamber 13, the valve piston 9 is moved to its top dead center. Thus, the O-ring 23 blocks fluid communication between the air channel 22 and the main valve control channel 40, while the O-ring 21 loses its sealing effect so that the accumulator 2 is fluidly connected to the main valve chamber 8 via the main valve intake channel 20 and the main valve control channel 40. Thus, compressed air flows from the accumulator 2 into the main valve chamber 8. As described above, the value obtained from dividing the maximum volume V1 of the main valve chamber 8 by the cross-sectional area S1 of the main valve control channel 40 is V1/S1=0.8. This value is set smaller than that of the conventional fastener driving tools. As with the design concept for the trigger valve intake channel 14, this value is determined based on the design concept that, with fastener driving tools having valve chambers, the time period required for the pressure in these valve chambers to be increased to a specific pressure by the introduction of the compressed air thereinto is reduced in accordance with an increase in the cross-sectional area of the channels used for the introduction of the compressed air with respect to the volume of these valve chambers. FIG. 10 shows the relationship between V1/S1, and the time period T1 until the main valve 19 returns to the initial position (lower dead position). FIG. 10 also shows the relationship between V1/S1 and the air consumption volume NL. The lower V1/S1 becomes, the lower T1 becomes as well. For the value in this first embodiment, V1/S1 is set to 0.8 at which T1 is approximately 7.0 ms. Consequently, the time period required for the pressure in the main valve chamber 8 to rise to a specific pressure by the introduction of compressed air thereinto can be reduced. Thus, the time period from when the valve piston 9 begins to return to the pre-nailing position (toward the top dead center) until the main valve 19 closes the main valve rubber 27 can be reduced. As a result, the time period to the restoration timing for the subsequent nail driving operation after the actual nail driving operation can be reduced. More specifically, the time period from when the trigger 39 and the push lever 42 are operated until the main valve reaches its bottom dead center as a result of the movement of the valve piston 9 to the pre-nailing position can be reduced. Further, since the time period for the main valve 19 to be closed is reduced, the amount of compressed air flowing from the accumulator 2 to the piston upper chamber can be reduced during movement of the main valve 19 toward its bottom dead center. Incidentally, even if V1/S1 is set to 1.0, T1 will be approximately 7.5 ms, which is sufficiently small in comparison to the conventional examples. If V1/S1 is set to 0.6, T1 can be made even smaller, approximately 5.5 ms. Consequently, the time period, following nailing, for the return to the pre-nailing state can be further reduced, while the amount of compressed air which flows from the accumulator 2 to the piston upper chamber can be further decreased. In addition, the value obtained from dividing the maximum volume V1 of the main valve chamber 8 by the cross-sectional area Sm of the main valve intake channel 20 is likewise set to V1/S1=0.8. The main valve intake channel 20 and the main valve control channel 40 become a contiguous inflow passage directing to the main valve chamber 8. In this connection, the main valve intake channel 20 should provide a performance at least equal to that of the main valve control channel 40. As a result, V1/Sm was also set to 1.0 or less. In addition, V1/S1 and V1/Sm need not be the same value provided that they are both 1.0 or less. Incidentally, there is the curved area at the main valve control channel 40. However, the curved area does not lead to a significant flow resistance because of the gentle arcuate shape in the curved area. Thus, there is no obstruction in the flow of air to be directed into the main valve chamber 8. As a result, the compressed air can instantaneously flow into the main valve chamber 8 so that a downward pressing force arises because of the difference in pressure receiving areas among the lower outer peripheral surface 52, the lower end surface 53, and the top end surface 54 of the main valve 19. In this first embodiment, by setting both V1/S1 and V1/Sm to 0.8, the time period required for the main valve 19 to move to the bottom dead center, that is, to return the main valve 19 to its pre-nailing position can be reduced to approximately 3.8 ms. This returning movement is also due to the pressing force arising from the compressed air flowing into the main valve chamber 8 and the biasing force of the main valve spring 28. Upon movement of the main valve 19 to its bottom dead center, the main valve 19 is coming into contact with the main valve rubber 27 to shut off fluid connection between the accumulator 2 and the piston upper chamber. Further, immediately before the main valve 19 reaches its bottom dead center, the main valve 19 is separated from the exhaust rubber 30 for providing fluid communication from the piston upper chamber with the atmosphere. As a result of the structural relationships, the main valve 19 is separated from the exhaust rubber 30 prior to the complete return of the main valve 19 to the bottom dead center. In this instance, since the accumulator 2 and the piston upper chamber are not yet completely blocked from each other, the accumulator 2 is connected to the atmosphere through the piston upper chamber and the air discharge passage 29, so that the compressed air is discharged unnecessarily into the atmosphere. However, by setting VI/S1 and V1/Sm to 1.0 or less, and also setting the cross-sectional area St of the trigger valve intake channel 14 to 2.75×0−6 (m2), the time period for the main valve 19 to move to the bottom dead center can be shortened, so that the unwanted consumption of the compressed air due to leakage of compressed air from the accumulator 2 to the atmosphere can be reduced as is apparent from FIG. 10. Then, underside of the piston 4a is then pressed by the compressed air accumulated in the return air chamber 33, and the piston 4a rapidly moves to its top dead center. The air in the piston upper chamber is released from the exhaust hole 49 to the atmosphere through the air discharge passage 29, and the fastener driving tool 1 returns to the initial state shown in FIG. 1. FIG. 12 shows a modification to the main valve control channel 40. In the first embodiment shown in FIG. 3, the bending portion (enclosed by the circle 51) of the main valve control channel 40, is configured into the gentle arcuate shape. In the modification shown in FIG. 12, the bending portion can include at least two bent areas. In the latter case, the bending angle is preferably not less than 100°. With this arrangement, air can be smoothly flowed into the main valve chamber 8, and the air in the main valve chamber 8 can be smoothly discharged therefrom, without excessive channel resistance. As an another modification, the cross-sectional area of the trigger valve intake channel 14 can be made large such as 3.00×10−6 (m2) or 3.25×10−6 (m2). In so doing, the unit rate of flow of the compressed air entering the trigger valve chamber 13 increases, so that the time period required for the pressure increase in the trigger valve chamber 13 can be shortened. Next, a fastener driving tool according to a second embodiment of the present invention will be described with reference to FIG. 13 to FIG. 16. The overall structure of the fastener driving tool 101 shown in FIG. 13 is substantially the same as the first embodiment except that the valve piston 9 in the first embodiment is not provided. Consequently, a detailed description will be omitted. In FIGS. 13 through 16, like parts and components are designated by reference numerals added with 100 to the reference numerals shown in FIGS. 1 through 11. A nail gun 101 includes a frame 160, a handle 160A, a nose 141 having an injection opening 146, an accumulator 102, a cylinder 103, a piston 104a, a driver blade 104b and its tip end 104c, a return air chamber 133, one way valve 134, air channels 135, 136, a piston bumper 137, a trigger 139, a trigger valve 106 including a plunger 107, a push lever 142, a magazine 144, and a main valve 126. The trigger valve 106 shown in FIGS. 13 and 14 mainly includes a valve bush 110, a plunger 107, and a spring 112. The valve bush 110 formed with a through hole is fixed to the frame 160 to form a trigger valve exterior frame which constitutes an outer wall of the trigger valve 106. The plunger 107 is provided reciprocably slidably with respect to the through hole of the valve bush 110. The plunger 9 has a bottom end in contact with the trigger 139. The spring 112 is interposed between the frame 160 and the plunger 107 for biasing the plunger 107 downward. The trigger valve 106 is fluidly connected to a cylindrical main valve control channel 140 extending from a main valve chamber 108. Specifically, the main valve control channel 140 is configured such that its cross-sectional area S1 is 3.2×10−5 (m2). In addition, an O-rings 125 is fitted on the valve bush 110 for continually blocking fluid connection between the main valve control channel 140 and an atmosphere. A trigger valve chamber 113 is defined by the frame 160 and the valve bush 110 secured to the frame 160. The plunger 107 extends through the trigger valve chamber 113, and has an upper portion extending through a through-hole formed in the frame 160. An annular space is defined between the through-hole and the plunger 107 for serving as a main valve intake channel 120. The main valve intake channel 120 has a cross-sectional area Sm of 3.2×10−5 (m2). The cross-section extends in a direction perpendicular to the flowing direction. An O-ring 115 is fitted at the through-hole of the frame 160 for shutting off the main valve intake channel 120 when the plunger 107 is moved to its top dead center. The plunger 107 has a lower section associated with the through hole of the valve bush 110. The lower section has an outer diameter slightly smaller than an inner diameter of the through hole of the valve bush 110 for defining an air channel 116 therebetween. This air channel 116 has a cross-sectional area of at least 3.2×0−5 (m2). An O-ring 118 is fitted onto the lower section of the valve bush 110 for closing the air channel 116 when the plunger 107 is moved to the bottom dead center. The main valve intake channel 120 and air channel 116 are alternately blocked in accordance with the sliding motion of the plunger 107. The main valve 126 is provided at an upper end and around an outer peripheral surface of the cylinder 103 as shown in FIG. 13. The main valve 126 includes a main valve 119 and a main valve spring 128 for biasing the main valve 119 toward its bottom dead center. An discharge passage 129 is formed above the main valve 119, and an exhaust port 149 in communication with the discharge passage 129 is formed at an upper portion of the frame 160. A main valve sectioning region 161 is provided as a part of the frame 160 for defining a main valve chamber 108 in which the main valve 119 is vertically movably disposed. The main valve chamber 108 is in communication with the main valve control channel 140. The main valve chamber 108 is hermetically provided by O-rings (not shown). The main valve chamber 8 has an internal volume variable in accordance with the vertical movement of the main valve 119, but has a maximum volume V1 of 2.56×10−5 (m3). As a result, the value obtained from dividing the volume V1 by the cross-sectional area S1 of the main valve control channel 40 is V1/S1=0.8≦1.0. Likewise, the value obtained from dividing the volume V1 by the cross-sectional area Sm of the main valve intake channel 120 is V1/Sm=0.8≦1.0. In addition, the main valve control channel 140 has a curving portion. The curving portion is formed into a gentle arcuate shape. The nail driving operation will be described. FIGS. 13 and 14 show a state in which compressed air from the compressor (not shown) is accumulated in the accumulator 102 through the hose (not shown). In this state, as shown in FIG. 14, the plunger 107 is positioned at its bottom dead center by the biasing force of the spring 112. Since the plunger 107 is positioned at the bottom dead center, the main valve intake channel 120 is open to provide fluid communication between the accumulator 102 and the trigger valve chamber 113. At the same time, the air channel 116 is closed by the O-ring 118, so the fluid connection between the trigger valve chamber 113 and the atmosphere is blocked. As shown in FIG. 14, since the trigger valve chamber 113 is in communication with the main valve control channel 140, a portion of the compressed air in an accumulator 102 also flows into the main valve control channel 140. Therefore, compressed air is accumulated in the main valve chamber 108 at the same pressure as in the accumulator 102. Since the part of the compressed air in the accumulator 102 flows into the main valve chamber 108, the main valve 119 is positioned at its bottom dead center as shown in FIG. 13 as a result of downward pressing load arising from the difference in pressure receiving areas between a lower peripheral surface 142 and an upper end surface 143 of the main valve 119, along with the biasing force of the main valve spring 128. Since the main valve 119 is positioned at the bottom dead center, the main valve 119 comes into contact with an upper end of the cylinder 103 to block fluid communication between the accumulator 102 and the piston upper space in the cylinder 103. In this case, the main valve 110 is separated from the frame 160 to open the air discharge passage 129. As a result, the piston upper chamber of the cylinder 103 is brought into communication with the atmosphere through the air discharge passage 129. Thus, the piston upper chamber assumes the atmospheric pressure. In addition, since the fluid connection between the piston upper chamber and the accumulator 102 is blocked, compressed air in the accumulator 102 does not flow into the piston upper chamber. As a result, the piston 104a is maintained at its top dead center position. FIGS. 15 and 16 show the state where the plunger 107 is pushed up to the top dead center by pulling the trigger 139 and pressing the push lever 142 against the workpiece. Since the upper portion of the plunger 107 extends through the O-ring 115, the fluid connection between the trigger valve chamber 113 and the accumulator 102 is blocked. In addition, the O-ring 118 loses its sealing effect to open the trigger valve control channel 116. As a result, the trigger valve chamber 113 and the atmosphere are fluidly connected to each other, so the inside of the trigger valve chamber 113 assumes the atmospheric pressure. The cross-sectional area of the air channel 116 is greater than that of the main valve channel 140. Thus, the channel resistance in air channel 116 is smaller than that in the main valve channel 140. The main valve control channel 140 connected to the trigger valve chamber 113 is also connected to the atmosphere, and in addition, the main valve chamber 108 connected to the main valve control channel 140 is also connected to the atmosphere and assumes the atmosphere pressure. When the main valve chamber 108 assumes roughly the atmospheric pressure, the main valve 119 moves to its top dead center as shown in FIG. 16 because compressed air pressure is applied to the lower outer peripheral surface 147 of the main valve 119 whereas the atmospheric pressure is applied to the upper end face 143 of the main valve. When the main valve 119 begins to move toward the top dead center, the accumulator 102 and a piston upper chamber in the cylinder 103 are brought into communication with each other, so that compressed air pressure is also applied to the lower end face 148 of the main valve 119. Thus, the main valve 119 moves rapidly toward the top dead center. As a result, the top end face of the main valve 119 comes into contact with the frame 160 to close the exhaust hole 149, so that fluid communication between the piston upper chamber and the atmosphere is blocked. In the second embodiment, similar to the first embodiment, the value obtained from dividing the maximum volume V1 of the main valve chamber 108 by the cross-sectional area S1 of the main valve control channel 140 is V1/S1=0.8. This is a design concept which, just as with the design concept in the first embodiment, was obtained as a result of recognition of the flow principle that, with fastener driving tools having valve chambers, the time period required for the pressure in these valve chambers to drop to a specific pressure due to the discharge of air can be reduced in accordance with an increase in cross-sectional area of the channels used to discharge air with respect to the volume of these valve chambers. The relationship between V1/S1 and the time period T1 from when the pressure in the main valve chamber 108 begins to drop until the main valve 119 moves to maximum displacement is basically the same as that shown in FIG. 9. For the value in this second embodiment, if V1/S1 is 0.8, T1 is approximately 7.0 ms. Further, even if V1/S1 is set to 1.0, T1 will be approximately 7.5 ms, which is sufficiently small in comparison with the conventional tools. With a fastener driving tool which is at least equipped with the main valve 119, the time period required for the pressure in the main valve chamber 108 to drop to a specific pressure due to the discharge of air can be reduced. Accordingly, the time period from when the trigger 139 and the push lever 142 are operated until the nailing motion occurs because of the displacement of the main valve 119 can be reduced. Incidentally, if V1/S1 is set to 0.6, T1 can be made even smaller, about 5.0 ms. Thus, time period until the nailing motion occurs can be further shortened. These values for T1 are sufficiently smaller than those in conventional fastener driving tools. The air in the main valve chamber 108 passes through the main valve control channel 140 and through the air channel 116 of the trigger valve 106 and is discharged into the atmosphere. In this case, since cross-sectional area of the air channel 116 is larger than that of the main valve control channel 140, the air channel 116 does not prevent the air from flowing from the main valve chamber 108 into the atmosphere. Consequently, the time period from when the trigger 139 and the push lever are operated until the main valve 119 is moved to the top dead center can be shortened. Thus, by setting the maximum volume of the main valve chamber 108 and the cross-sectional area of the main valve control channel 140 to the aforementioned values, the compressed air in the main valve chamber 108 can be discharged quickly, so that the time period until the main valve chamber 108 assumes the atmospheric pressure can be reduced. Furthermore, a so-called air damper in the main valve chamber 108 is not readily formed because of the improvement on the shape of the main valve control channel 140 and improvement on passing of air through the air channel 116. Accordingly, the discharge of air from the main valve chamber 108 can be improved even when the main valve 119 rises to the top dead center. Consequently, the main valve 119 can be moved immediately from the bottom dead center to the top dead center. By the movement of the main valve 119 from its bottom dead center to the top dead center, the compressed air rapidly flows from the accumulator 102 into the piston upper chamber, thereby rapidly moving the piston 104a toward its bottom dead center. Thus, the fastener is driven by the tip end 104c of the driver blade 104b connected to the piston 104a. The air in the underside of the piston 104a in the cylinder 103 flows through air channel 136 into the return air chamber 133. Further, a portion of the compressed air in the piston upper chamber also flows through the air channel 135 into the return air chamber 133, after the piston 104a is moved past the air channel 135. When the trigger 139 is returned or the pressing of the push lever 142 against the workpiece is stopped, the plunger 107 moves to the bottom dead center because of the pressure applied to the plunger 107 from the accumulator 102 and the biasing force of the spring 112 (FIG. 14). By the movement of the plunger 107 to the bottom dead center, the air channel 116 is closed by the O-ring 118, while the O-ring 115 loses its sealing effect. Thus, the compressed air in the accumulator 102 flows through the main valve intake channel 120 into the trigger valve chamber 113. In this case, because the trigger valve chamber 113 is in communication with the main valve control channel 140, the main valve chamber 108 is communicated with the accumulator 102 through the main valve intake channel 120. Thus compressed air is introduced into the main valve chamber 108. As described above, the value obtained from dividing the maximum volume V1 of the main valve chamber 108 by the cross-sectional area S1 of the main valve control channel 140 is V1/S1=0.8. This value is set smaller than that of the conventional fastener driving tools. As with the design concept for the trigger valve intake channel 14, this value is determined based on the design concept that, with fastener driving tools having valve chambers, the time period required for the pressure in these valve chambers to be increased to a specific pressure by the introduction of the compressed air thereinto is reduced in accordance with an increase in the cross-sectional area of the channels used for the introduction of the compressed air with respect to the volume of these valve chambers. The graph shown in FIG. 10 is also available in the second embodiment. The lower V1/S1 becomes, the lower T1 becomes as well. Since V1/S1 is set to 0.8, T1 is approximately 7.0 ms. Consequently, the time period required for the pressure in the main valve chamber 108 to rise to a specific pressure by the introduction of compressed air thereinto can be reduced. Thus, the time period from when the main valve 119 begins to return to the pre-nailing position (toward the bottom dead center) until the main valve 119 closes the top end of the cylinder 103 can be reduced. As a result, the time period from when the trigger 139 and the push lever 142 are operated until the main valve 119 reaches its bottom dead center (until the pre-nailing state for the subsequent nail driving operation) can be reduced. Further, since the time period for the main valve 119 to be closed is reduced, the amount of compressed air flowing from the accumulator 102 to the piston upper chamber can be reduced during movement of the main valve 119 toward its bottom dead center. Incidentally, even if V1/S1 is set to 1.0, T1 will be approximately 7.5 ms, which is sufficiently small in comparison to the conventional tools. If V1/S1 is set to 0.6, T1 can be made even smaller, approximately 5.5 ms. Consequently, the time period, following nailing, for the return to the pre-nailing state can be further reduced, while the amount of compressed air which flows from the accumulator 102 to the piston upper chamber can be further decreased. In addition, the value obtained from dividing the maximum volume V1 of the main valve chamber 108 by the cross-sectional area Sm of the main valve intake channel 120 is likewise set to V1/S1=0.8. The main valve intake channel 120 and the main valve control channel 140 become a contiguous inflow passage directing to the main valve chamber 108. In this connection, the main valve intake channel 120 should provide a performance at least equal to that of the main valve control channel 140. As a result, V1/Sm was also set to 1.0 or less. In addition, V1/S1 and V1/Sm need not be the same value provided that they are both 1.0 or less. Incidentally, there is the curved area at the main valve control channel 140. However, the curved area does not lead to a significant flow resistance because of the gentle arcuate shape in the curved area. Thus, there is no obstruction in the flow of air to be directed into the main valve chamber 108. As a result, the compressed air can instantaneously flow into the main valve chamber 108 so that a downward pressing force is imparted on the main valve 108 because of the difference in pressure receiving areas between the lower outer peripheral surface 147 and the top end surface 143 of the main valve 119. In the second embodiment, by setting both V1/S1 and V1/Sm to 0.8, the time period required for the main valve 119 to move to the bottom dead center, that is, to return the main valve 119 to its pre-nailing position can be reduced to approximately 3.8 ms. This returning movement is also due to the pressing force arising from the compressed air flowing into the main valve chamber 108 and the biasing force of the main valve spring 128. Upon movement of the main valve 119 to its bottom dead center, the main valve 119 is coming into contact with the upper end of the cylinder 103 to shut off fluid connection between the accumulator 102 and the piston upper chamber. Further, immediately before the main valve 119 reaches its bottom dead center, the main valve 119 is separated from the frame 160 for providing fluid communication from the piston upper chamber with the atmosphere. As a result of the structural relationships, the main valve 119 is separated from the frame 160 prior to the complete return of the main valve 119 to the bottom dead center. In this instance, since the accumulator 102 and the piston upper chamber are not yet completely blocked from each other, the accumulator 102 is connected to the atmosphere through the piston upper chamber and the air discharge passage 129, so that the compressed air is discharged unnecessarily into the atmosphere. However, by setting V1/S1 and V1/Sm to 1.0 or less, the time period for the main valve 119 to move to the bottom dead center can be shortened, so that the unwanted consumption of the compressed air due to leakage of compressed air from the accumulator 102 to the atmosphere can be reduced as is also apparent from FIG. 10. Then, underside of the piston 104a is then pressed by the compressed air accumulated in the return air chamber 133, and the piston 104a rapidly moves to its top dead center. The air in the piston upper chamber is released from the exhaust hole 149 to the atmosphere through the air discharge passage 129, and the fastener driving tool 1 returns to the initial state shown in FIG. 13. In the second embodiment, the bending portion of the main valve control channel 140 is configured into the gentle arcuate shape. As a modification, the bending portion can include at least two bent areas. In the latter case, the bending angle is preferably not less than 100°. With this arrangement, air can be smoothly flowed into the main valve chamber 108, and the air in the main valve chamber 108 can be smoothly discharged therefrom, without excessive channel resistance. With this arrangement, can be reduced the first time period from operation timing of the trigger 139 and the push lever 142 to the actual driving operation, and the second time period from release timing of the plunger 107 to the timing at which the main valve 119 has returned to its pre-driving position. A fastener driving tool according to a third embodiment of the present invention will next be described with reference to FIGS. 17 through 19. The overall structure of the fastener driving tool 201 is substantially the same as the first embodiment except that the main valve section 26 in the first embodiment is not provided. In FIGS. 17 through 19, like parts and components are designated by reference numerals added with 200 to the reference numerals shown in FIGS. 1 through 11. A nail gun 201 includes a frame 260, a handle 260A, a nose 241 having an injection opening 246, an accumulator 202, a cylinder 203, a piston 204a, a driver blade 204b and its tip end 204c, a return air chamber 233, one way valve 234, air channels 235, 236, a piston bumper 237, a trigger 239, a trigger valve 206 including a plunger 207, and a magazine 244. A piston upper chamber 266 is defined by the piston 204a, the cylinder 203, and the frame 260. The piston upper chamber 266 extends into an upper section of the frame 260. Further, an air channel 262 extends from the piston upper chamber 266 to the trigger valve 206. The trigger valve 206 shown in FIGS. 17 and 18 mainly includes a valve bush 210, a valve piston 209, the plunger 207, and a spring 212. The valve bush 210 formed with a through hole is fixed to the frame 260 to form a trigger valve exterior frame which constitutes an outer wall of the trigger valve 206. The valve piston 209 is reciprocally slidably disposed in the valve bush 210. The plunger 207 is provided reciprocably slidably with respect to the through hole of the valve bush 210. The plunger 207 has a bottom end in contact with the trigger 239. The spring 212 is interposed between the valve piston 209 and the plunger 207 for biasing the valve piston 209 and the plunger 207 in opposite directions, that is, the valve piston 209 is biased upward, and the plunger 207 is biased downward. An air channel 262 having a circular cross-section is formed within the frame 260 and extends from the piston upper chamber 266. The air channel 262 is connected to the trigger valve 206. In addition, an exhaust pipe 263 is provided in the handle 206A and has one end serving as an exhaust hole 249 opened at an end face of the handle 260A. The exhaust pipe 263 is connected to the trigger valve 206 at a position below the location at which the air channel 262 is connected to the trigger valve 206. Further, in the trigger valve 206, a valve plate 264 formed with a hole is disposed at a position between the connecting position between the air channel 262 and the trigger valve 206 and the connecting position between the exhaust pipe 263 and the trigger valve 206. The valve piston 209 extends through the hole of the valve plate 264. Further, a space is defined between the hole of the valve plate 264 and the valve piston 209. The space serves as an air channel 222. Another air channel 220 is formed at the part of the frame 260, the part serving as a part of the trigger valve 206. The air channel 220 is adapted to provide a communication between the accumulator 202 and the trigger valve 206. One end of the valve piston 209 in the sliding direction faces the accumulator 202. A valve piston rubber 221 is fitted in the vicinity of the opening of air channel 262 and at the upper end portion (a small diameter section) of the valve piston 209. The valve piston rubber 221 is adapted to come into -contact with the frame 260 near the periphery of air channel 220 when the valve piston 209 is at its top dead center (FIG. 18), and come into contact with an area near the periphery of the center hole of the valve plate 264 when the valve piston 209 is at its bottom dead center (FIG. 19). The air channel 222 provides fluid communication between the piston upper chamber 266 and the air channel 262 when the valve piston rubber 221 is released from the valve plate 264 in accordance with the movement of the valve piston 209 to its upper dead center. The valve piston 209 has a large diameter section provided with an O-ring 224 in sliding contact with the valve bush 210. The O-ring 224 provides sealing at the boundary between the valve piston 209 and the large diameter section. A trigger valve chamber 213 is defined by one end (lower end) of the large diameter section of the valve piston 209 and the valve bush 210. The trigger valve chamber 213 has an internal volume variable due to the sliding movement of the valve piston 209, and is formed such that a maximum internal volume V2 defined when the valve piston 209 is at the top dead center is 4.0×10−7 (m3). The O-ring 224 is adapted for blocking the fluid connection between the air channel 222 and the trigger valve chamber 213. The plunger 207 extends into the trigger valve chamber 213, and a top end faces the accumulator 2. The small diameter section of the valve piston 209 is formed with a central bore 261 in communication with the accumulator 202, and the large diameter section of the valve piston 209 is formed with a stepped bore in communication with the central bore 261. An O-ring 215 is assembled at the stepped bore. The plunger 207 has a small diameter section in association with the stepped bore. The outer diameter of the small diameter section of the plunger 207 is smaller than an inner diameter of the stepped bore. The small diameter section of plunger 207 is slidingly engagable with the O-ring 215 (FIG. 19) when the plunger 207 is moved to its top dead center. A trigger valve intake channel 214 is defined by the central bore 261. The plunger 207 has a large diameter section provided with an O-ring 218 and in association with the through hole of the valve bush 210. An outer diameter of the large diameter section of the plunger 207 is smaller than an inner diameter of the through hole of the valve bush 210 to thus define a trigger valve control channel 216. Consequently, the trigger valve intake channel 214 provides fluid communication between the accumulator 202 and the trigger valve chamber 213 when the small diameter section of the plunger 207 is disengaged from the O-ring 215. Further, the trigger valve control channel 216 provides fluid communication from the trigger valve chamber 213 to the atmosphere when the O-ring 218 is out of contact from the valve bush 210. The trigger valve intake channel 214 and trigger valve control channel 216 are alternately opened and blocked in accordance with the sliding motion of the plunger 207. The trigger valve intake channel 214 is formed such that its cross-sectional area St is 2.75×10−6 (m2). Further, the trigger valve control channel 216 is formed such that its cross-sectional area S2 is 1.98×10−6 (m2). As a result, the value obtained from dividing the maximum volume of the trigger valve chamber 213 by the cross-sectional area of the trigger valve control channel 216 is V2/S2=0.2. The structure of the trigger valve 206 is such that, when the valve piston 209 is positioned at the top dead center (FIG. 18), the valve piston rubber 221 is in abutment with the frame 260 near the air channel 220. Since the air channel 220 is closed by the valve piston rubber 221, the communication between the accumulator 202 and the piston upper chamber 266 through the air channels 262 and 220 is blocked. Further, the air channel 222 is opened to allow fluid communication between the piston upper chamber 266 and the exhaust pipe 263 through the air channels 262, 220,222. On the other hand, when the valve piston 209 is positioned at the bottom dead center (FIG. 19), the valve piston rubber 221 is seated on the valve plate 264 to close the air channel 222. Thus, fluid communication between the piston upper chamber 266 and the exhaust pipe 263 is shut off. Further, the air channel 220 is opened to provide fluid communication between the accumulator 202 and the piston upper chamber 266 through the air channels 262 and 220. When the plunger 207 is positioned at the top dead center (FIG. 19), the trigger valve control channel 216 is opened so that the trigger valve chamber 213 is communicated with the atmosphere, while the trigger valve intake channel 214 is closed by the O-ring 215 so that fluid communication between the accumulator 202 and the trigger valve chamber 213 is blocked. On the other hand, when the plunger 207 is positioned at its bottom dead center (FIG. 18), the trigger valve control channel 216 is closed by the O-ring 218, so that fluid communication between the trigger valve chamber 213 and the atmosphere is blocked, while the trigger valve intake channel 214 is opened so that the accumulator 202 and the trigger valve chamber 213 are communicated with each other. The nail driving operation will be described. FIGS. 17 and 18 show a state in which compressed air from the compressor (not shown) is accumulated in the accumulator 202 through the hose (not shown). In this state, as shown in FIG. 18, the plunger 207 is positioned at its bottom dead center by the biasing force of the spring 212. Since the plunger 207 is positioned at the bottom dead center, the main valve intake channel 214 is open to provide fluid communication between the accumulator 202 and the trigger valve chamber 213. At the same time, the trigger valve control channel 216 is closed by the O-ring 218, so the fluid connection between the trigger valve chamber 213 and the atmosphere is blocked. In this case, because of the biasing force of the spring 212 and the difference in pressure receiving areas between the lower end area and the upper end area of the valve piston 210, the valve piston 209 is positioned at its top dead center. Therefore, air channel 220 is closed by the valve piston rubber 221 to shut off communication between the accumulator 202 and the air channel 262. At the same time, since the air channel 222 is opened by the valve piston rubber 221, the air channel 262 and the exhaust pipe 263 are fluidly connected to each other. Thus, the piston upper chamber 266 assumes the atmospheric pressure, and the piston 204a is positioned at its top dead center as shown in FIG. 17. FIG. 19 shows the state where the plunger 207 is pushed up to the top dead center by pulling the trigger 239. In this state, the O-ring 218 loses its sealing effect to open the trigger valve control channel 216. As a result, the trigger valve chamber 213 and the atmosphere are fluidly connected to each other, so the trigger valve chamber 213 assumes the atmospheric pressure. Further, since the trigger valve intake channel 214 is closed by the O-ring 215, fluid communication between the accumulator 202 and the trigger valve chamber 213 is blocked. Since the pressure in the trigger valve chamber 213 becomes atmospheric pressure, pressure difference is provided between the accumulator side and the trigger valve chamber side of the valve piston 209. Thus, the valve piston 209 is moved to its bottom dead center. The relationship between V2/S2 and the time period T2 from when the pressure in the trigger valve chamber 213 begins to drop until the valve piston 209 moves to maximum displacement is basically the same as that shown in FIG. 6. In the third embodiment, if V2/S2 is 0.2, the time period for the valve piston 209 to move from its top dead center to its bottom dead center is approximately 0.75 ms. With a fastener driving tool which is at least equipped with the valve piston 209, by making the cross-sectional area of the trigger valve used to discharge the air larger with respect to the volume of the trigger valve 213, the time period required for the pressure in the trigger valve chamber 213 to drop to a specific pressure because of the discharge of air can be decreased. Accordingly, the time period from when the plunger 207 is pressed until the valve piston 209 moves to maximum displacement can be shortened. As a result, the time period from when the trigger 239 is operated until the nailing motion occurs due to the displacement of the valve piston 209 can be shortened. Incidentally, if V2/S2 is set to 0.15, T2 can be made even smaller, and if V2/S2 is set to 0.10, T2 can be made smaller still. These values for T2 are sufficiently smaller than those in conventional fastener driving tools. Thus, by setting the maximum volume V2 of the trigger valve chamber 213 and the cross-sectional area S2 of the trigger valve control channel 216 to the aforementioned values, discharge of the compressed air from the trigger valve chamber 213 can be promptly performed, and the time period until the trigger valve chamber 213 assumes the atmospheric pressure can be reduced. Furthermore, since the discharge of air from the trigger valve chamber 213 can be improved when the valve piston 209 is moved to the bottom dead center, a so-called air damper in which the pressure in the trigger valve chamber 213 impedes the movement of the valve piston 209 is not readily formed. Accordingly, the valve piston 209 can be moved immediately from the top dead center to the bottom dead center without being interrupted by the air damper. Incidentally, even though the valve piston 209 is biased toward the top dead center by the spring 212, the valve piston 209 is movable to the bottom dead center against the biasing force because of the pressure difference since the biasing force of the spring 212 is set beforehand to be weaker than the force caused by the pressure difference. As shown in FIG. 19, when the valve piston 209 reaches its bottom dead center, the air channel 222 is closed by the valve piston rubber 221 to block fluid communication between the air channel 262 and the exhaust pipe 263. At the same time, the air channel 220 is opened by the valve piston rubber 221, so that the accumulator 202 and air channel 262 are fluidly connected to each other. Thus, air flows from the accumulator 202 into the piston upper chamber 266, and the piston upper chamber 266 provides the pressure level the same as that in the accumulator 202. In this instance, since the pressure in the piston upper chamber 266 becomes greater than the pressure in the piston lower chamber in the cylinder 203, the piston 204a moves rapidly to its bottom dead point. Thus, the fastener is driven by the tip end 204c of the driver blade 204b. The air in the underside of the piston 204a in the cylinder 203 flows through an air channel 236 into the return air chamber 233. Further, a portion of the compressed air in the piston upper chamber 266 flows through the air channel 235 into the return air chamber 233, after the piston 204a is moved past the air channel 235. When the trigger 239 is returned, the plunger 207 moves to its bottom dead center because of the pressure applied from the accumulator 202 and the biasing force of the spring 212. In this case, as described above, the cross-sectional area St of the trigger valve intake channel 214 is set to 2.75×10−6 (m2), which is relatively larger than that of the conventional tool. This is due to a design concept in that the mass rate of flow is proportional to the cross-sectional area of the tube. That is, it is based on the discovery that, with fastener driving tools having valve chambers, the time period required for the pressure in these valve chambers to be increased to a specific pressure due to introduction of the compressed air thereinto is reduced in accordance with an increase in the cross-sectional area of the channels used for the introduction of the compressed air with respect to the volume of these valve chambers. At this point, since the cross-sectional area St of the trigger valve intake channel 214 is set to 2.75×10−6 (m2), the pressure in the trigger valve chamber 213 instantaneously rises. As a result, the time period required for the pressure in the trigger valve chamber 213 to rise to a specific pressure due to the flow of compressed air can be decreased. Thus, the time period from when the pressing force on the plunger 207 ceases until the valve piston 209 returns to the pre-nailing position can be shortened. The valve piston rubber 221 provided on the valve piston 209 comes into contact with the frame 260 at the top dead center of the valve piston 209, and comes into contact with the valve plate 264 at the bottom dead center of the valve piston 209. Therefore, a fluid connection between the piston upper chamber 266 and the accumulator 202, and a fluid connection between the piston upper chamber 266 and the exhaust pipe 263 is alternately provided. However, in more detailed aspect, during the movement of the valve piston 209 from its bottom dead center to its top dead center, the valve piston rubber 264 is out of contact from the frame 260 and from the valve plate 264. Accordingly, the connection between the piston upper chamber 266 and the accumulator 202 and the connection between the piston upper chamber 266 and the atmosphere can be simultaneously formed. As a result, the accumulator 202 and the atmosphere are connected, and the compressed air in the accumulator 202 is discharged into the atmosphere even during the movement of the valve piston 209 from its bottom dead center to its top dead center, which results in a waste of compressed air. However, since the valve piston 209 in the third embodiment can move from the bottom dead center to the top dead center more quickly than with the conventional tools, the amount of wasted compressed air which is unnecessarily discharged can be reduced. At that point, the air channel 220 is closed by the valve piston rubber 221 to block communication between the accumulator 202 and the air channel 262. Thus, the flow of air from the accumulator 202 to the piston upper chamber 266 stops. In addition, air channel 222 is opened, so that air channel 262 and the exhaust pipe 263 are fluidly connected to each other. As a result, the air which has been accumulated in the piston upper chamber 266 is discharged to the atmosphere through the air channel 262, 222, exhaust pipe 263 and the exhaust hole 249. Thus, the piston upper chamber 266 assumes the atmospheric pressure. Consequently, the piston 204a moves rapidly to the top dead point because the bottom of the piston 204a is imparted with a pressing force by the compressed air accumulated in the return air chamber 233, and the fastener driving tool 201 returns to the state shown in FIG. 17. Incidentally, the cross-sectional area of the trigger valve intake channel 214 can be made larger such as 3.00×10−6 (m2) or 3.25×10−6 (m2). With this arrangement, the unit rate of flow of the compressed air entering the trigger valve chamber 213 increases, so that the time period required for the pressure increase in the trigger valve chamber 213 can be shortened. Characteristic in nailing motion of the fastener driving tool according to the first embodiment will be described chronologically in comparison with a comparative fastener driving tool. In the graph shown in FIG. 20, the characteristics of the process of driving a nail into wood are shown for the fastener driving tool 1 involved in the first embodiment, and in the graph shown in FIG. 21, the characteristics of the process of driving a nail into wood with a fastener driving tool are shown for the comparative fastener driving tool. In these graphs, the x-axis represents time, and y-axis in FIG. 20(a) represents pressure in the trigger valve chamber 13, the main valve chamber 8, the accumulator 2, the piston 4a upper chamber, and the return chamber 33 in the fastener driving tool according to the first embodiment. Further, Y-axes in FIGS. 20(b) through 20(d) represent a displacement of the main valve 19, a displacement of the valve piston 9, and a displacement of the piston 4a according to the first embodiment. Here, the origin of the x-axis (0 ms) represents the time at which the plunger 7 is pressed and the pressure in the trigger valve chamber 13 begins to drop. The same is true with respect to FIGS. 21(a) through (d) for the comparative fastener driving tool. The dimensions in the comparative fastener driving tool involved in the nailing process were: maximum main valve chamber volume V1′=2.56×10−5 (m3); main valve control channel cross-sectional area S1′=0.8×10−5 (m2); V1′/S1′=3.2; maximum trigger valve chamber volume V2′=4.0×10−7 (m3); trigger valve control channel cross-sectional area S2′=0.465×10−6 (m2); V2′/S2′=0.86. The dimensions in the fastener driving tool involved in the first embodiment were: maximum main valve chamber 8 volume V1=2.56×10−5 (m3); main valve control channel 40 cross-sectional area S1=3.2×105 (m2); V1/S1=0.8; maximum trigger valve chamber 13 volume V2=4.0×10−7 (m3); trigger valve control channel 16 cross-sectional area S2=1.98×10−6 (m2); V2/S2=0.2. In FIGS. 20 and 21, A and A′ represent the timing at which pressure drop in the trigger valve chamber 13 is started, B and B′ represent the timing at which the pressure in the trigger valve chamber 13 becomes atmospheric pressure, C and C′ represents the timing at which the movement of the main valve 19 toward its upper dead center is started, D and D′ represent the timing at which the main valve 19 reaches its top dead center, E and E′ represent the timing at which the movement of the valve piston 9 toward its bottom dead center is started, F and F′ represent the timing that the valve piston 9 reaches its bottom dead center, and G and G′ represent the timing at which the piston 4a reaches its bottom dead center. By pressing the plunger 7, the pressure in the trigger valve chamber 13 drops and, in conjunction with this pressure change, the valve piston 9 begins to be displaced from the top dead center. At that point, since V2/S2=0.2 in the first embodiment has been set smaller than the value V2′/S2′=0.86 in the comparative tool, so the compressed air in the trigger valve chamber 13 can be instantaneously discharged through the trigger valve control channel 16 into the atmosphere. As a result, only 3.0 ms was required for the pressure drop to the atmosphere in the trigger valve chamber 13, whereas 11.3 ms was required for the pressure drop in the comparative tool (see B and B′). Further, only 0.74 ms was required for moving the valve piston 9 to its bottom dead center in the first embodiment whereas 0.85 ms was required for the movement in the comparative tool (see F and F′). Because of the displacement of the valve piston 9 toward its bottom dead center, the O-ring 23 loses its sealing effect, so that the air channel 22 and the main valve control channel 40 are fluidly connected to each other and the pressure in the main valve chamber 8 begins to drop. At that point, since V1/S1=0.8 in the first embodiment is smaller than V1′/S1′=3.2 in the comparative tool, the compressed air in the main valve chamber 8 can be instantaneously discharged through the main valve control channel 40 and the air channel 22 into the atmosphere. As a result, 22.4 ms was required for the pressure drop in the conventional main valve chamber to the minimum value for starting movement of the main valve from its bottom dead center. On the other hand, only 6.1 ms was required for the pressure drop in the main valve chamber 13 to the minimum value for starting movement of the main valve 19 from its bottom dead center (see C and C′). During this period, the pressure in the main valve chamber 8 rises temporarily due to the displacement of the main valve 19. However, since the cross-sectional area of the air channel 22 was set to be smaller than the cross-sectional area of the main valve control channel 40, excessive back-pressure is not applied to the main valve chamber 8. Then, the main valve 19 in the first embodiment reaches the top dead point after 7.1 ms (see D). By the movement of the main valve 19 toward its top dead center, the compressed air flows from the accumulator 2 to the piston upper chamber, so that the piston upper chamber becomes highly pressurized. Due to the pressure difference between the upper chamber and lower chamber of the piston 4a, the piston 4a drops to the bottom dead center for driving the fastener 5. As a result of this, the process from when the worker pulls the trigger 39 until the fastener 5 is driven is completed. In the first embodiment, the process only requires 11.3 ms, whereas the comparative tool requires 27.1 ms (see F and F′). This difference clearly represents an improvement on the nailing response. In addition, as a result of experimentation using a variety of fastener driving tools and investigating what degree of improvement in the response was sufficient for the effect to be perceived, it was found that if nailing occurred within 12 ms after the trigger is pulled and the push lever was pressed against the workpiece, the response was perceived to be good, the work became easy to perform, and it became easy to drive fasteners in a continuous manner. Moreover, it was found that as this amount of time grew longer, the response gradually grew worse, and in the vicinity of the 27.1 ms of the conventional tool, the work became difficult to perform and it became difficult to drive fasteners in a continuous manner. From this perspective as well, the response was improved, and the work performance was improved as well based on the fastener driving tool 1 in the first embodiment. Next, an entire one-shot process starting from the pushing timing of the plunger 7 to the recovery timing to the initial state for starting the next nail driving operation will be described with reference to FIGS. 22(a) through 23(e). These graphs are particularly useful for the explanation of the process of returning to the initial state. In these graphs, the x-axis represents time, and y-axis in FIG. 22(a) represents pressure in the trigger valve chamber 13, the main valve chamber 8, the accumulator 2, the piston 4a upper chamber, and the return chamber 33 in the fastener driving tool according to the first embodiment. Further, Y-axes in FIGS. 22(b) through 22(d) represent a displacement of the main valve 19, a displacement of the valve piston 9, a displacement of the piston 4a, and a displacement of a tool itself according to the first embodiment. Here, the origin of the x axis (0 ms) represents the time at which the plunger 7 is pressed and the pressure in the trigger valve chamber 13 begins to drop. The same is true with respect to FIGS. 23(a) through (e) for another comparative fastener driving tool. The dimensions in the comparative fastener driving tool involved were: maximum main valve chamber volume V1′=2.621×10−5 (m3); main valve control channel cross-sectional area S1′=1.963×10−5 (m2); V1′/S1′=1.335; main valve intake channel cross-sectional area Sm′=0.41×10−5 (m2); V1′/Sm′=6.5; trigger valve intake channel cross-sectional area St′=1.78×10−6 (m2). The dimensions in the fastener driving tool involved in the first embodiment were: maximum main valve chamber 8 volume V1=2.56×10−5 (m3); main valve control channel 40 cross-sectional area S1=3.2×10−5 (m2); V1/S1=0.8; main valve intake channel 20 cross-sectional area Sm=3.2×105 (m2); V1/Sm=0.8; trigger valve intake channel cross-sectional area St=2.75×10−6 (m2). In FIGS. 22(a) through 23(e), A through G and A′ through G′ are the same as those shown in FIGS. 20(a) through 21(d). H and H′ represent the timing at which the returning motion of the main valve is started. I and I′ represent the timing at which the main valve is returned to its initial position. J and J′ represent the timing at which the returning motion of the valve piston is started. K and K′ represent the timing at which the valve piston is returned to its initial position. L and L′ represent the timing at which the piston is returned to its initial position. M and M′ represent the timing at which the entire tool is displaced by a maximum amount. In the first embodiment, 6.9 ms was required for starting nail driving by starting the movement of the piston 4a whereas the comparative tool required 22.2 ms for the starting (see FIGS. 22(d) and 23(d). In reaction to the movement of the piston, the tool body itself begins to move upward. Subsequently the piston 4a reaches the bottom dead center, and nailing was completed after 11.3 ms in the first embodiment, as opposed to after 26.9 ms in the comparative tool. The upward displacement of both the fastener driving tool 1 and the comparative tool at this point was 5 mm. Further, in the first embodiment, the upward displacement of the tool itself reached 10 mm at 18.6 ms, whereas in the comparative tool, the upward displacement of the tool itself reached 10 mm at 35.1 ms (see FIGS. 22(e) and 23(e)). At this point, the relative position between the push lever 42 and the nose 41 was restored to the initial position, and the plunger 7 which has been biased upward by the push lever 42 is returned to its initial position. In the first embodiment, the valve piston 9 began to move due to the pressure of the accumulator 2 and the pressing force of the spring 12 at 18.6 ms, and the valve piston 9 was returned to the initial position at 20.3 ms. On the other hand, in the comparative tool, the valve piston began to move at 35.2 ms, and returned to the initial position at 37.4 ms (See FIGS. 22(c) and 23(c)). By the movement of the valve piston 9, the compressed air in the accumulator 2 flows into the main valve chamber 8 through the main valve intake channel 20 and the main valve control channel 40. As a result in the first embodiment, the main valve 19 began to move at 21.4 ms, whereas in the comparative tool, the main valve 19′ began to move at 38.9 ms (see H and H′). In addition, in the first embodiment, the main valve 19 was returned to the initial position at its bottom dead center at 25.2 ms, whereas in the comparative tool, the main valve 19′ was returned to the initial position at its bottom dead center at 44.3 ms (see I and I′). Simultaneously, the compressed air filled in the piston upper chamber is released to the atmosphere through air channel 29 and the exhaust hole 49, and the tool was returned to the initial state. As described above, in the first embodiment, the time period from the moment when either the pulling of the trigger 39 is released or the pressing of the push lever 42 against the workpiece is released (18.6 ms) until the main valve is closed (25.2 ms) was 25.2 ms−18.6 ms=6.6 ms. On the other hand, in the comparative tool, the time period was 44.3 ms−35.2 ms=9.1 ms. In addition, experimentations were conducted using a variety of fastener driving tools for investigating how much the time period needed to be shortened in order for a sufficient improvement on response to be perceived, the time period being from the moment when either the pressing of the trigger 39 was released or the pressing of the push lever 42 against the workpiece is released until the main valve is closed. As a result of experiments, it was found that if the time period is within 7 ms, the response was perceived to be extremely good facilitating driving work and continuous driving. Therefore, since the first embodiment requires the time period of within 7 ms, the transition to the next nailing operation can proceed rapidly to improve the response. In addition, because of the prompt closure of the main valve, unnecessary air consumption can be avoided. While the invention has been described in detail and with reference to specific embodiments thereof, it would be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to a fastener driving tool such as a nail gun driven by compressed air, and more particularly, to such fastener driving tool improving drive response and decreasing air consumption. Heretofore, fastener driving tools such as nail guns have existed which drive fasteners such as nails or staples using compressed air as the power source. In such fastener driving tools, compressed air is supplied to a piston upper chamber defined by an inner surface of a cylinder and a piston for rapidly displacing the piston to perform nailing. Compressed air is supplied from an external source and temporarily stored in an accumulator formed within a frame of the nail gun. The accumulator and the piston upper chamber are connected by a channel, but one or more valves which are switched between open and shut-off positions are provided along this channel. These valves are designed to open or shut-off the channel by supplying or expelling compressed air in valve chambers constituted by the spaces each adjacent to each valve. Typically the structure is such that a first valve is activated as a result of external operation of a trigger or the like, and this operation allows a downstream passage to be communicated with or to be shut-off from the first valve. Thus, a downstream valve chamber is brought into communication with or shutting-off from the upstream passage, thereby sequentially activating or deactivating the downstream valves. In addition, a time period starting from completion of the nail driving operation to restoration to an initial state for the next nailing operation is dependent upon the circulation speed of the compressed air in the fastener driving tool after the trigger is released, and the movement speed of the valves in proportion to this circulation speed. That is, the time period is dependent on the shut-off speed for shutting off the piston upper chamber in the cylinder from the accumulator by a valve caused by, after releasing the trigger or the like, circulation of the compressed air through the channel in the fastener driving tool as a result of the returning motion of a plunger which had been pressed by this trigger. In a conventional fastener driving tools as disclosed in Japanese Patent Publication No.S58-50833, valve activation is performed sequentially from valves whose valve chamber volume is small to valves with large valve chamber in order to stabilize operation of the valves irrespective of the speed with which the trigger is pulled. Since with this structure the valves are sequentially activated by compressed air, a time period starting from pulling the trigger and/or pushing operation of a push lever against a workpiece to a start of the nailing driving motion is highly dependent upon the time required to sequentially activate the valves. In order to reduce this time period and increase response, Japanese Patent Publication No. H7-112674 discloses a nail gun, in which a main valve is divided into first and second valves, so that kinetic energy of the first valve is utilized to improve the operating speed of the second valve. With this structure in which the main valve is divided into two valves, only the time period from when the second valve begins to move until it moves to maximum displacement is reduced. The time period from both pulling the trigger and pushing the push lever onto the workpiece to the operation timing of the first valve is still not reduced. In addition, since only the time period from when the second valve begins to move until it moves to maximum displacement is reduced, it was only possible to reduce the time period from when the trigger is pulled until nailing is performed. Consequently, a time period from the completion timing of the nail driving operation to the start timing of the next nail driving operation cannot be reduced when continuous nailing is performed. That is, a response cannot be improved. Laid-open Japanese Patent Application Kokai No. H11-33930 discloses a structure in which, an internal volume of a main valve chamber for accommodating therein a main valve is increased. With this arrangement, air damping behavior due to compression of the main valve chamber does not occur when the main valve rises and is contained in the main valve chamber. With this structure in which the volume of the main valve chamber is increased, the amount of compressed air accumulated in the main valve chamber increases. For this reason, the time period for discharging the compressed air out of the main valve chamber is increased, which degrades the response. Laid-open Japanese Patent Application Kokai No. H5-138548 discloses communication of a piston lower chamber with a trigger valve chamber. The movement speed of a valve piston and a main valve are increased as a result of the pressure which is generated from the movement of the piston. With this structure in which the piston lower chamber and trigger valve chamber are connected, at the instant that the piston passes through the one-way valve disposed at an intermediate region of the cylinder, compressed air flows into the trigger valve chamber and closes the main valve. Therefore, the nailing force was reduced. Moreover, extremely complicated structure results. Another conventional fastener driving tool has been proposed. The tool includes a trigger valve and main valve. A trigger valve exterior frame internally defines a trigger valve chamber. The trigger valve includes a plunger extending through the trigger valve exterior frame and the trigger valve chamber and slidably movable as a result of the movement of the trigger and the abutment of the push lever against the workpiece. The movement of the plunger selectively shuts off a fluid communication between the accumulator and the trigger valve chamber and between the trigger valve chamber and an atmosphere. However, the resultant arrangement cannot provide high response for discharging compressed air from the main valve. Still another conventional fastener driving tool is proposed in which a main valve is not provided, but a trigger valve is additionally equipped with a valve piston. The valve piston is reciprocably slidably disposed in a trigger valve exterior frame, and has one side in the sliding direction facing the accumulator. The valve piston alternately opens and blocks a channel from the piston upper chamber connected to the trigger valve exterior frame to the accumulator and a channel from the piston upper chamber to the atmosphere. With this fastener driving tool, the displacement of the valve piston serves to select the air channel and control the nailing of the fastener. However, the speed of the displacement of the valve piston is low, and the delay in the displacement of this valve piston can cause other control to be delayed as well. Consequently, the problem arises that the time lag from when the operator begins the nailing operation until the fastener is actually driven becomes large, response becomes poor to lower workability. In addition, the problem arises that when many fasteners are to be driven in a short period of time, the aforementioned time lag makes continuous nailing difficult to perform. In addition, with the conventional fastener driving tools, after nailing, in order to return the piston to the pre-nailing position, the piston upper chamber and the atmosphere are communicated with each other for releasing the compressed to the atmosphere, while the valve is closed for preventing the compressed air from flowing from the accumulator into the piston upper chamber. However, during the period from when the valve begins to close until it is completely closed, the accumulator and the piston upper chamber are communicated with each other, and the piston upper chamber and the atmosphere are also communicated with each other. Accordingly, the compressed air in the accumulator would in some cases flow unnecessarily into the piston upper chamber and is expelled into the atmosphere. This causes an increase in air consumption, which consequently requires a high-performance compressor or the like to produce compressed air. | <SOH> SUMMARY OF THE INVENTION <EOH>It is therefore an object of the present invention is to provide a fastener driving tool improving the response and continuous shots or nailing performance in nailing work, yet reducing the consumption of compressed air. This and other objects of the present invention will be attained by A fastener driving tool including a frame, a cylinder, a piston, a main valve, a main valve chamber section, a trigger valve, and a main valve control channel section. The frame defines therein an accumulator that accumulates a compressed air. The cylinder is disposed within the frame. The piston is reciprocally slidably disposed within the cylinder. A piston upper chamber is defined by an inner peripheral surface of the cylinder and an upper surface of the piston. The main valve alternately opens and blocks a fluid communication between the piston upper chamber and the accumulator. The main valve chamber section defines therein a main valve chamber in which the main valve is movably disposed. The main valve chamber provides a maximum internal volume. The trigger valve alternately opens and blocks a fluid communication from the accumulator to the main valve chamber, and a fluid communication from the main valve chamber to an atmosphere. The main valve control channel section defines therein a main valve control channel that provides a fluid connection between the main valve chamber and the trigger valve. A value obtained from dividing the maximum internal volume of the main valve chamber by a cross-sectional area of the main valve control channel being not more than 1.0. In another aspect of the invention, there is provided a fastener driving tool including a frame, a cylinder, a piston, a trigger, and a trigger valve provided with a trigger valve exterior frame, a valve piston and a plunger. The frame defines therein an accumulator for accumulating a compressed air. The cylinder is disposed within the frame. The piston is reciprocally slidably disposed within the cylinder. A piston upper chamber is defined by the frame, an inner peripheral surface of the cylinder and an upper surface of the piston. The trigger functions as an operation input member. A trigger valve alternately opens and blocks a fluid communication between the piston upper chamber and the accumulator and a fluid communication between the piston upper chamber and an atmosphere. The trigger valve exterior frame is in fluid communication with the piston upper chamber and is formed with a through hole. The valve piston is reciprocably slidably disposed in the trigger valve exterior frame. The valve piston is movable between its top dead center where piston upper chamber is communicated with the atmosphere and its bottom dead center where the piston upper chamber is communicated with the accumulator. The valve piston has a first section exposed to the accumulator and formed with a trigger valve intake channel opened to the accumulator and a second section in sliding contact with the trigger valve exterior frame. A trigger valve chamber is defined by the second section and the trigger valve exterior frame and provides a maximum internal volume. The plunger is movable between its top dead center and its bottom dead center and has a first portion associated with the valve piston and a second portion associated with the through hole. A trigger valve control channel is formed between the second portion and the through hole and has a cross-sectional area. The trigger valve control channel is opened when the plunger is moved to its top dead center. A value obtained from dividing the maximum volume of the trigger valve chamber by the cross-sectional area of the trigger valve control channel is not more than 0.20. Further, in the fastener driving tool including the frame, the cylinder, the piston, the trigger, and the trigger valve provided with the trigger valve exterior frame, the valve piston and the plunger, the trigger valve intake channel has a cross-sectional area of not less than 2.75×10 −6 m 2 , and the trigger valve chamber has a maximum internal volume of 4.0×10 −7 m 3 . | 20050121 | 20070102 | 20050721 | 57535.0 | 1 | KERSHTEYN, IGOR | PNEUMATICALLY OPERATED FASTENER DRIVING TOOL | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,163 | ACCEPTED | Driver circuit for light emitting element | Disclosed is a display driver that includes a first current driver circuit, a second current driver circuit and a reference current source circuit. The first current driver circuit, which has plural current sources the output current values of which are determined based on a reference current, and switch circuits for on/off controlling the current path between the plural current sources and the current output terminal based on video signal composed of plural bits. The first current driver circuit outputs a first output current conforming to the video signal. The second current driver circuit outputs the second output current conforming to the video signal, while the reference current source circuit variably controls the reference current based on the value of the video signal. A current that is the result of combining the first and second output currents from the first and second current driver circuits is output as an output current. An amount of change in the output current that corresponds to a change of one LSB of the video signal, is varied in accordance with the value of the video signal, the gamma characteristic is approximated by piece-wise linear approximation and the overall luminance of the display pane is variably controlled based on a control signal from a panel luminance adjustment circuit. | 1. A driver circuit comprising: an input terminal for receiving an input signal; an output terminal for outputting an output current; a reference current source circuit including a reference current source that generates a reference current prescribing an amount of change in the output current that corresponds to a change in a unit quantity of said input signal, said reference current source circuit varying the value of said reference current based on said input signal; and an output current generating circuit for generating said output current conforming to said input signal based on said reference signal to output said output current at said output terminal; wherein a characteristic of the input signal, which is input to said input terminal, versus the output current that is output from said output terminal is made a predetermined input/output characteristic of a prescribed non-linearity. 2. The driver circuit according to claim 1, wherein said input signal is a digital signal; and wherein a unit change in the input signal corresponds to the single-bit equivalent of the least significant bit of the input signal. 3. The driver circuit according to claim 1, wherein said input signal is a digital signal; and wherein said output current generating circuit includes: a first current generating circuit for generating a first output current corresponding to said input signal based on said reference current source; and a second current generating circuit, including a current source distinct from said reference current source, for generating a second output current corresponding to said input signal; a current that is the result of combining said first and second output currents being output as said output current from said output terminal. 4. The driver circuit according to claim 3, wherein a range of said input signal from a minimum value to a maximum value is divided into plural intervals; and wherein said first output current is zero at one end of one interval, with said second output current being an output current output from said output terminal. 5. The driver circuit according to claim 4, wherein the current value of the output current that corresponds to at least one end of said interval of the input signal is set to a current value that corresponds to an ideal value of the predetermined non-linear input/output characteristic, and a linear approximation of the non-linear input/output characteristic is performed on a per-interval basis. 6. A driver circuit for a light-emitting element in which emission of light is controlled in accordance with a supplied current, said driver circuit receiving a video signal that enters from an input terminal, generating a current that corresponds to the video signal and outputting the current from an output terminal, said driver circuit comprising: a decoder receiving and decoding the video signal composed of plural bits to output the decoded signal; a first current driver circuit, including a plurality of current sources, respective values of current thereof being decided based upon an applied reference current; and a plurality of switch circuits that on/off control current paths between the plurality of current sources and a current output terminal based upon an output signal of said decoder, for generating and outputting a first output current that corresponds to the value of the video signal; a second current driver circuit outputting a second output current that corresponds to the value of said video signal; and a reference current source circuit , including a current source that generates the reference current, for varying the output reference current based upon the video signal; wherein a current that is the result of combining the first and second output currents output from said first and second current driver circuits respectively, is output from the output terminal as an output current; and an amount of change in the output current that corresponds to a change in a unit quantity of the video signal is varied in accordance with the video signal. 7. The driver circuit for a light-emitting element according to claim 6, wherein the unit quantity of the video signal is a single-bit equivalent of the least significant bit of the video signal. 8. The driver circuit for a light-emitting element according to claim 6, wherein said reference current source circuit includes a control circuit for varying the current value of said reference current output based on said video signal. 9. The driver circuit for a light-emitting element according to claim 6, wherein at least one of said first current driver circuit, second current driver circuit and said reference current source circuit variably controls the output current based on the totality of bits of said video signal. 10. The driver circuit for a light-emitting element according to claim 6, wherein a range of said input signal from a minimum value to a maximum value is divided into plural intervals; and wherein said first output current is zero at one end of one such interval, with said second output current being an output current. 11. The driver circuit for a light-emitting element according to claim 10, wherein the current value of the output current that corresponds to at least one end of said interval of the video signal is set to a current value that corresponds to a logic value of the predetermined non-linear input/output characteristic, and a linear approximation of the non-linear input/output characteristic is performed on a per-interval basis. 12. The driver circuit for a light-emitting element according to claim 6, further comprising a luminance adjustment circuit for varying a control voltage, which is output thereby, based upon a control signal that enters from a control terminal; wherein said reference current source circuit receives the control voltage output from said luminance adjustment circuit and varies the current value of the output reference current based upon the control voltage. 13. The driver circuit for a light-emitting element according to claim 12, wherein said second current driver circuit varies the current value of said second output current based on said control voltage. 14. The driver circuit for a light-emitting element according to claim 6, wherein said first current driver circuit includes a multiple-output current mirror circuit, having an input terminal to which the reference current is input, for outputting currents that mirror the reference current from respective ones of a plurality of output terminals; and a plurality of switching elements, each of which has a control terminal that receives the lower-order bit signal of the video signal or a signal obtained by decoding the lower-order bit signal of the video signal by said decoder, a first end connected to a respective output terminal of the plurality of output terminals of said current mirror circuit, and a second end connected to the current output terminal. 15. The driver circuit for a light-emitting element according to claim 6, wherein said reference current source circuit includes: a plurality of current sources having first ends connected in common to a first potential; a decoder for the reference current source circuit, receiving and decoding the video signal; and a plurality of switching elements, which have first ends connected to output terminals of respective ones of said plurality of current sources and second ends connected in common to a reference current output terminal that outputs the reference current, for being on/off controlled based upon a signal that is output from said decoder for the reference current source circuit. 16. The driver circuit for a light-emitting element according to claim 6, wherein said reference current source circuit includes: one or a plurality of current sources having a first end connected to a first potential and an output terminal connected to a current output terminal that outputs the reference current; a decoder for the reference current source circuit, receiving and decoding the video signal; and a voltage selection circuit for supplying a bias voltage to said one or plurality of current sources based upon result of decoding by said decoder for the reference current source circuit; said current source varying the output current from the output terminal of said current source in accordance with the bias voltage. 17. The driver circuit for a light-emitting element according to claim 16, wherein said voltage selection circuit in said reference current source circuit includes: a decoder for the second current driver circuit, receiving and decoding the video signal a resistor circuit, which has a plurality of resistors connected serially between a high reference potential and a low reference potential, for outputting corresponding voltages from a predetermined plurality of taps from among the high reference potential, low reference potential and nodes between mutually adjacent ones of said resistors; and a plurality of switching elements, connected between the plurality of taps of said resistor circuit and an output terminal that outputs the bias voltage, for being on/off controlled by an output signal from said decoder for the second current driver circuit. 18. The driver circuit for a light-emitting element according to claim 15, further comprising a luminance adjustment circuit for generating a variable control voltage based upon a control signal applied thereto; wherein the control voltage is supplied as the first potential of said current-source circuit. 19. The driver circuit for a light-emitting element according to claim 6, wherein said second current driver circuit further includes: a decoder for the second current driver circuit, receiving and decoding the video signal; a first group of current sources having first ends connected in common to a first potential; and a first group of switching elements, having first ends connected to output terminals of respective ones of said first group of current sources and second ends connected in common to a current output terminal, for being on/off controlled based upon a signal from said decoder for the second current driver circuit received at a control terminal thereof. 20. The driver circuit for a light-emitting element according to claim 19, wherein said second current driver circuit further includes: a second group of current sources having first ends connected in common to a second potential; and a second group of switching elements, having first ends connected to output terminals of respective ones of said second group of current sources and second ends connected in common to a current output terminal, for being on/off controlled based upon a signal from said decoder for the second current driver circuit received at a control terminal thereof. 21. The driver circuit for a light-emitting element according to claim 6, said second current driver circuit includes: a decoder for the second current driver circuit, receiving and decoding the video signal; one or a plurality of current sources, each having a first end connected to a first potential and an output terminal connected to a current output terminal that outputs the second output current; and a voltage selection circuit for supplying a bias voltage to said one or plurality of current sources based upon result of decoding by said decoder; said current source varying the output current from the output terminal of said current source in accordance with the bias voltage. 22. The driver circuit for a light-emitting element according to claim 21, wherein said second current driver circuit includes: one or a plurality of current sources, each having a first end connected to a second potential and an output terminal connected to a current output terminal that outputs the second output current; and a voltage selection circuit for supplying a bias voltage to said one or plurality of current sources based upon result of decoding by said decoder for the second current driver circuit; said current source varying the output current from the output terminal of said current source in accordance with the bias voltage. 23. The driver circuit for a light-emitting element according to claim 21, wherein said voltage selection circuit includes: a resistor circuit, having a plurality of resistors serially connected between a high reference potential and a low reference potential, for outputting corresponding voltages from a predetermined plurality of taps from among the high reference potential, low reference potential and nodes between mutually adjacent ones of said resistors; and a plurality of switching elements, connected between the respective plurality of taps of said resistor circuit and an output terminal that outputs the bias voltage, for being on/off controlled by an output signal from said second decoder. 24. The driver circuit for a light-emitting element according to claim 21, further comprising a luminance adjustment circuit for generating a variable control voltage, which is output thereby, based upon a control signal applied thereto from a control signal input terminal; wherein the control voltage that is output from said luminance adjustment circuit is supplied as the first potential of said second current driver circuit. 25. The driver circuit for a light-emitting element according to claim 22, further comprising a luminance adjustment circuit for generating a variable control voltage, which is output thereby, based upon a control signal applied thereto from a control signal input terminal; wherein the control voltage that is output from said luminance adjustment circuit is supplied as the second potential of said second current driver circuit. 26. The driver circuit for a light-emitting element according to claim 11, wherein the non-linear input/output characteristic is made a prescribed gamma-value characteristic, and the output current produced is one obtained by correcting the video signal in accordance with the predetermined gamma value. 27. A display device having the driver circuit for a light-emitting element set forth in claim 6 as a driver circuit for driving a display element of a display-element panel, wherein it is unnecessary to provide a gamma correction circuit in front of said driver circuit for driving the display element. 28. A display device comprising: a display panel having a plurality of scan lines arrayed along the horizontal direction, a plurality of data lines arrayed along the vertical direction and a plurality of display elements provided at intersections of said scan lines and data lines; a scan driver for driving the scan lines; and a data driver, receiving a video signal, for driving the data lines; wherein said data driver has the driver circuits for light-emitting elements set forth in claim 6 as driver circuits for driving the data lines. 29. The display device according to claim 28, wherein said drivers for light-emitting elements, which are provided in correspondence with colors of the light-emitting elements, are controlled individually on a per-color basis to uniformalize panel luminance. 30. A semiconductor device having the driver circuit set forth in claim 1. 31. A current-output-type digital-to-analog converter, receiving a digital signal as an input for converting the digital signal to an output current and outputting the output current, said converter comprising: a first current driver circuit, having a plurality of current sources in which values of current to be output are decided based upon an applied reference current, and a plurality of switch circuits that on/off control current paths between the plurality of current sources and a current output terminal based upon the input signal of multiple bits, for generating and outputting a first output current that conforms to the input signal of multiple bits; a second current driver circuit, for generating and outputting a second output current correcting the output current in accordance with the input signal; and a reference current-source circuit for outputting the reference current, and for varying the reference current based upon the value of the input signal; wherein a current that is the result of combining the first and second output currents output from said first and second current driver circuits respectively, is output as the output current; and an amount of change in the output current that corresponds to a change in a unit quantity of the digital signal is varied in accordance with the value of the input signal. | FIELD OF THE INVENTION This invention relates to a driver circuit for a light-emitting element and to a display device. More particularly, the invention relates to a driver circuit and device that perform a gamma correction. BACKGROUND OF THE INVENTION An arrangement of the kind illustrated in FIG. 25 by way of example is known as an electroluminescent storage device (refer to the specification of Japanese Patent Kokai Publication No. JP-A-2-14868 pages 5 and 6, FIG. 2). As shown in FIG. 25, this conventional electroluminescent device includes an electroluminescent element 40; a plurality of memory cells 22 corresponding to the electroluminescent element 40; a current source 28 (a current mirror comprising transistors 26 and 27); current control means (transistors) 24, which correspond to the plurality of memory cells 22, connected to corresponding ones of the memory cells 22 and responsive to signals, which are held in the memory cells 22, for controlling current that flows from the current source 28 to the electroluminescent element 40; and control logic, a column data register, display input/readout logic and row strobe register, etc., none of which are shown, for supplying the memory cells 22 with signals Bn to B0 representing luminance required by the electroluminescent element 40. Current corresponding to the signals held in the memory cells 22 flows through transistors 24n to 24n-3, current that is the sum of the currents that flow through the transistors 24n to 24n-3 enters the drain of the transistor 26 constituting the input end of the current source (current mirror) 28, and the mirror current of the input current is output from the drain of the transistor 27, which constitutes the output end of the current source (current mirror), and is supplied to the electroluminescent element 40. In the arrangement shown in FIG. 25, the relationship between the input data signal and the output current (and therefore luminance) is a positive proportional relationship (gamma value=1.0). Consequently, in order to perform a correction such as one where the gamma value is 2.2, the gamma correction must be applied to the video signal stored in the memory cells 22. Since the human eye is sensitive to dark colors, an image will appear more natural if the luminance of the input signal satisfies a luminance=(signal strength) (e.g., γ=1.8, 2.2, etc.) relationship rather than a positive proportional relationship. In general, therefore, the relationship between panel luminance and the video signal is provided with a gamma characteristic. Generally, in a case where a gamma correction is made, as shown in FIG. 26, a gamma correction circuit 131 for making the relationship between the input signal (video signal) and luminance conform to the gamma characteristic is provided on the input side of a display element driver circuit 132. The signal that has been gamma-corrected by the gamma correction circuit 131 is input to the display element driver circuit 132, and the data signal is supplied from the display element driver circuit 132 to a display element panel 133 via a data signal line. Since the gamma correction circuit 131 is necessary in this arrangement, however, not only is the circuitry large in size but an additional problem is a reduction of grayscales that can be expressed. For example, if the gamma characteristic (gamma value=2.2) is expressed using an 8-bit (256 grayscales) display element driver circuit 132, only 187 grayscales can be realized. In order to implement a gamma correction having grayscale (256 grayscales) the same as those of the input signal, on the other hand, it is necessary that the gamma correction circuit 131 and display element driver circuit 132 be capable of supporting more grayscales than those of the input signal, as illustrated in FIG. 27. Consequently, the circuitry is large in size. In the example illustrating in FIG. 27, both the gamma correction circuit 131 and display element driver circuit 132 support 512 grayscales (nine bits). [Patent Document 1] Japanese Patent Kokai Publication No. JP-A-2-148687, pages 5 and 6, FIG. 2) Thus, in a case where the conventional display circuit is provided with a gamma correction function, a problem which arises is the large size of the circuitry, as mentioned above. The same is true also in a case where a gamma correction of grayscales identical with those of the input signal is performed. SUMMARY OF THE DISCLOSURE Accordingly, it is an object of the present invention to provide a driver circuit that makes it possible to reduce the size of circuitry and diminish chip area in realizing a gamma characteristic, as well as to a display device having this driver circuit. Another object of the present invention is to provide a driver circuit that makes it possible to adjust the overall luminance of a display panel while maintaining the gamma characteristic, as well as a display device having this driver circuit. The above and other objects are attained by the present invention, which enables optimum display by varying the reference current, flowing through a reference current source circuit, based on a video signal, for approximating the input/ output characteristic of the EL element driver circuit to e.g. the gamma characteristic. More specifically, the reference current prescribes the amount of change in the output current corresponding to a unit change of the input signal A driver circuit in accordance with one aspect of the present invention, includes a reference current source circuit for varying the value of the reference current based on the input signal; and an output current generating circuit for generating the output current conforming to the input signal based on the reference signal to output the output current at the output terminal, wherein a characteristic between the input signal that is input to an input terminal and the output current that is output from the output terminal is made a predetermined input/output characteristic of a prescribed non-linearity. In the present invention, the input signal is a digital signal, and a unit change of the input signal corresponds to a one bit equivalent which is the least significant bit (LSB) of the digital signal. In the present invention, the input signal is a digital signal, and the output current generating circuit includes a first current generating circuit for generating a first output current corresponding to the input signal based on the reference current source, and a second current generating circuit for generating a second output current corresponding to the input signal from a current source distinct from the reference current source. A current, that is the result of combining (adding or subtracting) the first output current and the second output current is output as the output current from the output terminal. A range of the input signal from a minimum value to a maximum value is divided into plural intervals, and the first output current is zero at one end of one such interval, with the second output current being the aforementioned output current output from the output terminal. According to the present invention, the current value of the output current at least one of the leading end and the trailing end of said interval of the input signal is set to a current value corresponding to a theoretical (ideal) value of an input/output characteristic of predetermined non-linearity and linear approximation of the non-linear input/output characteristic is performed from one interval to the next. In another aspect, the present invention provides a driver circuit for a light-emitting element in which a light emitting element, having light emission controlled responsive to the current supplied, receives a video signal input via an input terminal, to generate the current corresponding to the video signal, to output the current thus generated at an output terminal, in which the driver circuit for a light-emitting element comprises a decoder supplied with the video signal composed of plural bits to decode the video signal thus supplied, a first current driver circuit including a plurality of current sources, the current value in each of which is prescribed based on the value of a given reference current, and a switch circuit for on/ off control of a current path between the plural current sources and a current output terminal, based on an output signal of the decoder, to output a first output current conforming to the value of the video signal. The driver circuit for a light-emitting element also comprises a second current driver circuit outputting a second output current conforming to the value of the video signal, and a reference current source circuit having a reference current source outputting the reference current, with the reference current source circuit variably controlling the reference current output based on the value of the video signal. A current that is the result of combining the first and second output currents from the first and second current source circuits is output at the output terminal as an output current, and the amount of change in the output current corresponding to a change in a unit quantity of the video signal is varied responsive to the video signal. In another aspect, the present invention provides a driver circuit for a light-emitting element in which a luminance adjustment signal is used to control the current source to adjust the luminance of the light emitting element. More specifically, the present invention preferably includes a luminance adjustment circuit for variably generating the control voltage based on an input control signal. The output current value of the output reference current, output by the reference current source circuit, is changed based on the control voltage. According to the present invention, the second current driver circuit varies the current value of the output current based on the control voltage. According to the present invention, the second current driver circuit includes a multi-output current mirror circuit supplied with the reference current at an input end for outputting the output current, which is a turned versions of the reference current, from plural outputs thereof, and a plurality of switch elements receiving signals obtained on decoding the video signal by the decoder at control terminals thereof, with the switch elements having one ends connected to the plural output ends of the current mirror circuit and having the other ends connected in common to the current output ends. According to the present invention, the reference current source circuit includes a plurality of current sources having one ends connected in common to a first potential, a decoder for the reference current source circuit, supplied with and decoding the video signal to output decoded results, and a plurality of switch elements having one ends connected to output ends of the plural current sources and having the other ends connected in common to a reference current output ends outputting the reference current. The switch elements are controlled on or off based on a signal output from the decoder for the reference current source circuit. According to the present invention, the reference current source circuit includes one or more current sources having one end connected to a first potential and having each output end connected to a current output end outputting the reference current, a decoder for the reference current source circuit, supplied with and decoding the video signal to output decoded results, and a voltage selection circuit supplying a bias current to the one or more current sources, based on decoded results by the decoder for the reference current source circuit. The current source(s) vary the output current of the current source(s) responsive to the bias current. According to the present invention, the second current driver circuit includes a decoder for the second current driver circuit supplied with and decoding the video signal to output decoded results, a first set of current sources, having one ends connected in common to a first potential, and a first set of switch devices having one ends connected to output ends of the current sources of the first set and having the opposite ends connected in common to the current output end. The switch devices of the first set, receiving a signal of the decoder for the second current driver circuit at control terminals thereof, are thereby turned on or off. According to the present invention, the second current driver circuit includes a second set of current sources, having one ends connected in common to a second potential, and a second set of switch devices having one ends connected to output ends of the current sources of the second set and having the opposite ends connected in common to the current output end. The switch devices of the second set, receiving a signal of the decoder for the second current driver circuit at control terminals thereof, are thereby turned on or off. According to the present invention, the second current driver circuit includes a decoder for the second current driver circuit supplied with and decoding the video signal to output decoded results, one or more current sources having one end(s) connected to a first potential and having output end(s) connected to a current output end outputting the second output current, and a voltage selection circuit for supplying a bias voltage to the one or more current source(s), based on the decoded results by the decoder for the second current driver circuit. The current source(s) vary an output current from the output end of the current source(s) responsive to the bias voltage. According to the present invention, the control voltage, output from the luminance adjustment circuit, is supplied as the first potential and/or the second potential of the second current driver circuit. The meritorious effects of the present invention are summarized as follows. According to the present invention, it is possible to reduce the circuit scale of the driver circuit for a light-emitting element having a gamma characteristic and to reduce the chip area. In accordance with the present invention, the overall luminance of a panel can be adjusted while maintaining the gamma characteristic. Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description in conjunction with the accompanying drawings wherein only the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of carrying out this invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawing and description are to be regarded as illustrative in nature, and not as restrictive. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating the configuration of a driver circuit for a light-emitting element according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of the configuration of a PMOS power supply used in the embodiment of the present invention. FIG. 3 is a diagram illustrating another example of the configuration of a PMOS power supply used in the embodiment of the present invention. FIG. 4 is a diagram illustrating of the configuration of an NMOS power supply used in the embodiment of the present invention. FIG. 5 is a diagram illustrating another example of the configuration of an NMOS power supply used in the embodiment of the present invention. FIG. 6 is a graph illustrating a gamma curve (gamma value=2.2) and input/output characteristic of a 64-grayscale driver circuit for a light-emitting element according to the present invention. FIG. 7 is a graph illustrating input/output characteristics of a driver circuit for a light-emitting element in the embodiment of the present invention. FIG. 8 is a diagram illustrating the configuration of a reference current supply circuit in the embodiment of the present invention. FIG. 9 illustrates the operation of the reference current supply circuit in the embodiment of the present invention. FIG. 10 is a diagram illustrating another configuration of a driver circuit for a light-emitting element according to an embodiment of the present invention. FIG. 11 is a diagram illustrating a configuration of a voltage selection circuit of the reference current supply circuit of FIG. 10. FIG. 12 is a diagram illustrating another configuration of a voltage selection circuit of the reference current supply circuit of FIG. 10. FIG. 13 illustrates the operation of the voltage selection circuit of FIG. 12. FIG. 14 is a diagram illustrating a configuration of a second current driver circuit according to an embodiment of the present invention. FIG. 15 is a diagram illustrating another configuration of a second current driver circuit according to an embodiment of the present invention. FIG. 16 illustrates the operation of the current driver circuit of FIG. 15. FIG. 17 is a diagram illustrating a further configuration of a second current driver circuit according to an embodiment of the present invention. FIG. 18 is a diagram illustrating a configuration of a voltage selection circuit of the second current driver circuit shown in FIG. 17. FIG. 19 is a diagram illustrating a further configuration of a second current driver circuit according to an embodiment of the present invention. FIG. 20 is a diagram illustrating a configuration of the voltage selection circuit of the second current driver circuit shown in FIG. 19. FIG. 21 illustrates the operation of the second current driver circuit shown in FIG. 20. FIG. 22 is a diagram illustrating a configuration of a display driving device according to an embodiment of the present invention. FIG. 23 is a diagram illustrating a configuration of a data driver of FIG. 22. FIG. 24 is a diagram illustrating a configuration of a display device of the present invention. FIG. 25 is a diagram illustrating a configuration of a conventional EL storage display device. FIG. 26 is a diagram illustrating a configuration of a display device having the gamma correcting function. FIG. 27 is a diagram illustrating another configuration of a display device having the gamma correcting function. PREFERRED EMBODIMENTS OF THE INVENTION The present invention will be described below with reference to the accompanying drawings. The overall structure of a display device according to an embodiment of the present invention will be described with reference to FIG. 24. The display device incorporates a gamma correction function in a display-element driver circuit 130 to which an input signal (video signal) is applied for driving current through a display element of a display panel. By virtue of this structure, the area of the circuitry and area of the chip when the device is integrated can be reduced in comparison with the conventional structure shown in FIGS. 26 and 27. A further characterizing feature is that the display-element driver circuit 130 supports 256 grayscale levels (represented by eight bits) and is capable of delivering a 256 grayscale input signal to a display element (panel) 133. A gamma correction circuit supporting 512 grayscale levels (represented by nine bits) and a display-element driver circuit supporting nine bits, which are employed in the arrangement of FIG. 27, are unnecessary. As illustrated in FIG. 1, a driver for a display device according to the present invention comprises: a first current driver circuit 10, which has a plural number of current sources (M0 and M1 to Mk) for outputting current of a value decided based upon a preset reference current (IREF), and switch circuits(SW1 to SWk) for on/off controlling current paths between the plurality of current sources (M1 to Mk) and a current output terminal (2), based upon a vide signal to send out a first output current (IOUT1) corresponding to the value of the video signal (grayscale); a second current driver circuit 11 for outputting a second output current (IOUT2) conforming to video signal (grayscale, interval), and a reference current source circuit 12, which has a current source that generates the reference current (IREF), for variably controlling the reference current (IREF) based on the value of video signal (grayscale, interval). A current that is the result of combining the first output current (IOUT1) from the first current driver circuit and the second output current (IOUT2) from the second current driver circuit 11 is output from the output terminal 2 as an output current (IOUT). An amount of change in the output current (IOUT) that corresponds to a change in unit value of the video signal is varied in accordance with the value of the video signal, and the input/output characteristic of output current with respect to the video signal has a desired characteristic. In an embodiment of the present invention, by changing the reference current (IREF), which is for outputting a driving current conforming to the video signal, in accordance with the value of the video signal (grayscale), the increment (amount of change in units of the LSB) in output current of the driver circuit is varied, whereby a gamma characteristic having a gamma value of 2.2 or the like can be approximated with a piece-wise linear approximation method. In addition, the overall luminance of the display panel can be varied by varying the reference current (IREF) and/or second output current based upon an applied panel-luminance adjustment signal. The present invention will now be described in greater detail with reference to the drawings illustrating a preferred embodiment to which the invention is applied. FIG. 1 shows a circuit configuration of a driver circuit for a light-emitting element according to an embodiment of the present invention. Meanwhile, the driver circuit for a light-emitting element, described in the following first embodiment, is a sink-current type current driver circuit for supplying the output current IOUT (sink current) to the light emitting elements of the display panel. It is assumed that, in the embodiment, now explained, the luminance of the light emitting elements, such as EL elements, is proportional to the current value of the driving current supplied to the light emitting elements. Referring to FIG. 1, the driver circuit for a light-emitting element of the present embodiment includes: a first current driver circuit 10 for generating and outputting the driving current corresponding to the value (grayscale) of video signal, made up of digital signal, a second current driver circuit 11 for generating and outputting the driver circuit corresponding to the value (grayscale) of video signal, a reference current source circuit 12, a panel luminance adjustment circuit 14, and a decoder 13 for decoding the video signal and sending the decoded result to the first current driver circuit 10. In the case of 2k grayscales, where k is a preset positive integer not less than 2, the video signal is k-bit signal. The reference current source circuit 12, which receives the video signal and a control voltage VCON output from the panel luminance adjustment circuit 14, generates and outputs a reference current IRef corresponding to the input video signal. The reference current IRef, output from the reference current source circuit 12, may also be varied by the VCON. The first current driver circuit 10, which receives the reference current (IREF) and an output signal from the decoder 13, turns on/off the current paths between the plural current sources M1 to Mk and the output terminal 12, by a plural number (k) of switches SW1 to SWk, which are on/off controlled based on the output signal from the decoder 13, supplied with digital video signal from the input terminal 1, to output a first output current IOUT1 corresponding to the lower bits of the video signal. For example, if the video signal is “zero”, the switches SW1 to SWk are all off, such that the first output current (IOUT1) is 0. The second current driver circuit 11 which receives the video signal and a control voltage VCON output from the panel luminance adjustment circuit 14 to output a second output signal IOUT2 that is varied in accordance with the video signal and the control voltage VCON. It is noted that the second current driver circuit 11 is also provided with a decoder for decoding video signal, switches, and with a plural number of current sources, as will be explained subsequently. A current that is the result of combining the first output current (IOUT1) from the first current driver circuit 10 and the second output current (IOUT2) from the second current driver circuit 11 (sum current) is output from the output terminal 12 to a data line, not shown, as an output current IOUT for driving light emitting elements, such as EL elements, not shown, from the output terminal 12. In the present embodiment, the reference current IREF, output from the reference current source circuit 12, prescribes the amount of change in the output current when the digital video signal is changed by one LSB (least significant bit). In the reference current source circuit 12, the reference current IREF is variably controlled by the video signal and by the control voltage VCON from the panel luminance adjustment circuit 14. This configuration represents a feature of the present invention. In case the current value of the reference current IREF is large or small, the amount of change in the output current IOUT (quantization step) in case the video signal has been changed by one LSB is large or small, respectively. Referring to FIG. 1, the configuration of the first current driver circuit 10 is explained in further detail. The first current driver circuit includes k switches SW1 to SWk, having one ends connected in common to the output terminal 2 and having control terminals supplied with decoded result signals from the decoder 13 so as to be thereby turned on or off. The other ends of the k switches SW1 to SWk are connected to drains of NMOS transistors M1 to Mk respectively. An NMOS transistor M0, having a source grounded, and having a drain and a gate coupled to each other and to an output end of the reference current source circuit 12, on one hand, and NMOS transistors M1 to Mk, having sources grounded and having gates connected in common to the connection node of the gate and the drain of the NMOS transistor M0, on the other hand, form a multi-output current mirror circuit. The reference current IRef is input to an input side transistor M0 of a multi-output current mirror M0 to Mk. The mirror current is output from each of the current sources M1 to Mk of the first current driver circuit 10. The W/L ratio (gate width/ gate length ratio, also termed the ‘aspect ratio’) of the NMOS transistors M1 to Mk is set so as to be 20, 21, . . . , 2(k−1) times the W/L ratio of the of the NMOS transistor M0, with the current driving capability of the transistors also being 20, 21, . . . , 2(k−1) times in keeping with the W/L ratio. From the drains of the NMOS transistors M1 to Mk, having the associated switches turned on, the currents weighted to 20 (=1), 21(=2), . . . , 2(k−1) times the drain current of the NMOS transistor M0 (sink currents) are output as mirror currents, respectively. The output current (IOUT1) from the first current driver circuit 10 can be made to correspond to the currents of 2k grayscales (video signal is of k bits). Alternatively, the video signal may be divided into plural intervals from the smallest value up to the largest value and variable control may be exercised for each of the interval. For example, if, in the driver circuit for a light-emitting element of 64 grayscales, with the video signal being 6 bits, the maximum amplitude of the video signal (64 grayscales) is divided with equal range into four intervals, and an output signal at an end of each interval is made coincident with the gamma characteristic, by way of piece-wise linear approximation, control of the current of 64 grayscales/four intervals=16 grayscales (four bits), that is, lower four bits, is taken charge of by the first current driver circuit 10. It is noted that, if the number of grayscales, taken charge of by the first current driver circuit 10, is a power of 2 (21), the decoder 13 of FIG. 1 is unneeded, such that lower bits (i bits) of the binary video signal, entered from the input terminal 1, are supplied to the control terminals switches SW1 to SWi, respectively. If the number of grayscales, taken charge of by the first current driver circuit 10, differs from the power of 2, the video signal needs to be decoded by the decoder 13 to control the switches SW1 to SWk on or off, using the decoder 13. If the W/L ratio of the NMOS transistors M1 to Mk is of the same value, that is, no weighting is applied, lower bit signals of the binary video signal need to be decoded by the decoder 13 to control the switches SW1 to SWk on or off. That is, 2i NMOS transistor current sources SW1 to SW2i may be provided in the first current driver circuit 10 in association with lower i bits of the video signal, and 2i switches SW1 to SW2i may be provided in keeping with 2i current sources, with the decoder 13 then decoding lower i bits of the video signal to perform on/off control of the switches SW1 to SW2i for connecting a number of the current sources corresponding to the value of the lower i bits of the video signal to the output terminal 2. The second current driver circuit 11 outputs the second output current (IOUT2) of the driver circuit for a light-emitting element in association with video signal (2k grayscales). The output current IOUT from the output terminal 2 is the current sum of the first output current IOUT1 from the first current driver circuit 10 and the second output current IOUT2 from the second current driver circuit 11. That is, with the present embodiment, the desired output current IOUT may be obtained on combining the output current IOUT1 of the first current driver circuit 10 to the second output current IOUT2 from the second current driver circuit 11, thereby realizing optimum piece-wise linear approximation of the output current IOUT from the output terminal 2 to the gamma characteristics. The gamut from the minimum value (e.g. zero grayscale) to the maximum value (e.g. 2k grayscales) of the video signal may be divided into plural intervals, with the first output current IOUT1 being zero at one end of a interval, with the second output current IOUT2 being the output current IOUT. A panel luminance adjustment signal, fed to the panel luminance adjustment circuit 14, is used for varying the reference current IREF and the current value of the second current driver circuit 11 to perform adjustment control to cause light emitting elements, not shown, to emit light at an optimum luminance. In the example shown in FIG. 1, an output current IOUT from the output terminal 2 is output as a sink current, however, it may, of course, be designed as a source current. In the latter case, the current mirror circuit 15, forming the current source of the first current driver circuit 10, is formed by a PMOS transistor (PMOS current source) instead of by an NMOS transistor, the current source of the second current driver circuit 11 is formed by a PMOS current source, and the current source of the reference current source circuit 12 is formed by an NMOS current source. FIGS. 2 and 3 show an example of a current source composing the reference current source circuit 12 shown in FIG. 1 (source current outputting current source). The current source in the present embodiment is formed by a PMOS transistor (also termed a PMOS current source). FIGS. 4 and 5 show an embodiment in which the current source is formed by an NMOS transistor (also termed an NMOS current source). In the present embodiment, the PMOS current source and the NMOS current source are associated with the configuration shown in FIGS. 2 and 3 and with the configuration shown in FIGS. 4 and 5, respectively. In the circuit configuration, shown in FIG. 2, different bias voltages are applied to the gates of plural transistors forming plural current sources outputting different current values. In the circuit configuration, shown in FIG. 3, a constant bias is applied to the gates of plural transistors, forming plural current sources outputting different currents, while the W/L ratio of the transistors is different from one transistor to another to yield different output currents. More specifically, in FIG. 2, gate voltages (bias voltages) VPref1 to VPrefn of transistors MPrefa1 to MPrefan, making up the PMOS current sources, are controlled to vary currents IPref1 to IPrefn flowing through the respective current source transistors. The configuration shown in FIG. 4 is the same as that of FIG. 2 except for the difference in polarity (the transistors used being NMOS transistors). In the configuration shown in FIG. 3, the common gate voltage VPref of transistors MPrefh1 to MPrefhn, making up the PMOS current sources, is used, and the W/L ratio of the transistors MPrefh1 to MPrefhn is adjusted to vary the currents Ipref1 to IPrefn flowing through the transistors MPrefh1 to MPrefhn. The configuration shown in FIG. 5 is similar in this respect. In FIGS. 2 and 3, the currents IPref1 to IPrefn flowing through the plural transistors (current sources) may be varied by varying the source potentials VPCON1 to VNCONn of the PMOS transistors. In FIGS. 4 and 5, the currents INref1 to INrefn flowing through the plural transistors (current sources) may be varied by varying the source potentials VNCON1 to VNCONn of the NMOS transistors. The source potential VPCON of the PMOS current source of FIGS. 2 and 3 and the source potential VNCON of the NMOS current sources of FIGS. 4 and 5 correspond to the control voltage VCON output from the panel luminance adjustment circuit 14 (see FIG. 1). The luminance of the light emitting elements is varied in proportion to the current flowing through the light emitting elements. Hence, the luminance of the display panel in its entirety may be adjusted by controlling the voltages of the control voltages VPCON and VNCON. The PMOS current sources, shown for example in FIGS. 2 and 3, are used as a current source of the reference current source circuit 12 of FIG. 1, the current sources IPref1 to IPrefn are selected with a switch, based on the video signal, and the current of the selected current source is output as the reference current IRef. The NMOS current sources, shown for example in FIGS. 4 and 5, are used as a current source of the second current driving source 11 of FIG. 1, the current sources INref1 to INrefn are selected with a switch, based on the video signal, and the current of the selected current source is output as the reference current IOUT2. Specified examples of the configuration of the second current driver circuit 11 and the reference current source circuit 12 will be explained later in detail. For the 64-grayscale driver circuit for a light-emitting element, current control of the driver circuit for a light-emitting element, in case the 64 grayscales are equally divided into four interval, is now explained. In the following example, it is assumed that, for the gamma value=2.2 and for the video signal of 64 grayscales, the driver circuit for a light-emitting element outputs the current of 64 μA. In FIG. 6, a graph a shows a gamma curve (gamma value=2.2), while a graph b shows an example of input/output characteristic of the 64-grayscale driver circuit for a light-emitting element according to the present invention (piece-wise linear approximation characteristic). Referring to FIG. 6, the input/output characteristic b of the 64 grayscales (grayscale 0 to grayscale 63) of the driver circuit for a light-emitting element according to the present invention are set so that the output current IOUT at each of the beginning and terminal ends of each of four intervals of grayscales 0 to 15, 16 to 31, 32 to 47 and 48 to 63 will be coincident with the value of the gamma curve (?=2.2). By variably controlling the value of the reference current IRef in each interval, the amount of change in the output current (gradient) against change of one grayscale (1 LSB of the video signal), are different, thus realizing piece-wise linear approximation. The output currents across neighboring intervals, such as the output current in the grayscale 15 of the interval 1 and the output current in the grayscale 16 of the interval 2, exhibit smooth continuous transition, thus achieving an optimum approximation. Meanwhile, the gamma curve (?=2.2) presents a curve convexed towards below in each interval against the approximation b according to the present invention. Although the 64 grayscales are divided into four equal intervals, the approximation may be improved in accuracy by increasing the number of intervals. FIG. 7 shows input/output characteristics of the driver circuit for a light-emitting element of 64 grayscales in case the value of the reference current IRef is changed using the panel luminance adjustment signal of FIG. 1. That is, by varying the potential supplied to the current source of the reference current source circuit 12 (see FIGS. 2 or 3) by the control voltage VCON output from the panel luminance adjustment circuit 14, the reference current IRef output from the reference current source circuit 12 is varied to a characteristic equal to 1.2 or 0.8 times the gamma curve (?=2.2). As a result, a desired output current characteristic conforming to the video signal may be obtained. Moreover, the second output current IOUT2, output from the second current driver circuit 11, may be varied by the control voltage VCON output from the second current driver circuit 11 to change a characteristic to a characteristic which is equal to 1.2 or 0.8 times the gamma curve (?=2.2), in conjunction with the control of the reference current source circuit 12. The operating principle of current control by the control voltage VCON is now schematically described. In case the control voltage VCON (and hence the source potential VPCON of FIGS. 2 and 3 and the source potential VNCON of FIGS. 4 and 5) is changed, the gate-to-source voltage VGS of the MOS transistor (current source) shown in FIGS. 2 to 5 is varied and the drain-to-source current IDS is also varied, whereby current values of the reference current IRef, and the second output current IOUT2, output from the second current driver circuit 11, may be varied. Since the luminance of the light emitting element is varied in proportion to the current flowing therein, the overall luminance of the display panel (33 of FIG. 24) may be adjusted by changing the reference current IRef and the second output IOUT2 output from the second current driver circuit 11. In the present embodiment, the luminance of the display panel is adjusted by a panel luminance adjustment signal input from a control signal input terminal 3. That is, the panel luminance adjustment circuit 14 variably controls the control voltage VCON based on the panel luminance control signal input from the control signal input terminal 3 to adjust the potential VPCON of the reference current source circuit 12 and the potential VNCON of the second current driver circuit 11 to desired voltages. With the present embodiment, having the above configuration, the overall luminance of the display panel in its entirety may be adjusted as the gamma characteristic is maintained. That is, with the driver circuit for a light-emitting element, having the above-described structure, panel luminance adjustment and gamma correction may be achieved simultaneously. Several illustrative structures of the reference current source circuit 12 of the present embodiment, shown in FIG. 1, are hereinafter explained. FIG. 8 shows an illustrative structure of the reference current source circuit 12 shown in FIG. 1. Referring to FIG. 8, the reference current source circuit 12 includes n PMOS current sources IRef1 to IRefn and selects the current sources IRef1 to IRefn by the switches SWRef1 to SWRefn to variably control the value of the output current IRef. Meanwhile, the current sources IRef1 to IRefn of FIG. 8 correspond to the PMOS current source transistors MPrefa1 to MPrefan of FIG. 2 and to the PMOS current source transistors MPrefh1 to MPrefhn of FIG. 3. The decoder 121 decodes video signal to output control signals Dcona1 to Dconan. The switches SWRef1 to SWRefn have one ends connected to output terminals of the PMOS current sources IRef1 to IRefn, while having the opposite ends connected in common and having control terminals supplied with the control signals Dcona1 to Dconan from the decoder 121. A common connection point of the switches SWRef1 to SWRefn is connected to an output terminal of the reference current IRef. The current values of the PMOS current sources IRef1 to IRefn are weighted with preset weight values, such that the current values of the reference current IRef may be varied by the current sources IRef1 to IRefn, as selected by the switches SWRef1 to SWRefn. The reference current IRef determines the amount of change (unit change amount) in the output current when the digital video signal is changed by one LSB, such that, by changing the reference current IRef, the amount of the current changed by each LSB may be changed depending on the value of the video signal (grayscale). The amount of the current changed for one LSB of the video signal, that is, the input/output characteristic, may be changed responsive from interval to interval, in order to realize optional non-linearity for each interval. Since the lower the grayscale, the more curved is the characteristic of the gamma characteristic, and the higher the grayscale, the more linear is the characteristic thereof, the video signal supplied to the first current driver circuit 10 (totality of bits) are used as the video signal supplied to the reference current source circuit 12. That is, in the reference current source circuit 12, all of the k bits corresponding to 2k grayscales are used for control. As a modification, a preset number of bits (k bits) of the video signal may be input. By providing n PMOS current sources IRef1 to IRefn in the reference current source circuit 12, the 2k grayscales can be divided into n or more intervals. Since the current values, supplied to the light emitting elements in association with video signal, is known from the outset, the current weighting of the n PMOS current sources IRef1 to IRefn is set so that the necessary current will be output from the driver circuit for a light-emitting element responsive to the video signal. FIG. 9 shows a truth table illustrating the operation of the decoder 121 (see FIG. 8) for driving the current source of the reference current source circuit 12, formed by four current sources (n=4 in FIG. 8), for the 64-grayscale (6-bit) video signal, in terms of the correspondence between the video signal and the control signals Dcona1 to Dconan. In FIG. 9, numerals 1, 0 denote switch on and off, respectively. In FIG. 9: in an interval 1 for the video signal 0 to 15, the control signal Dcona1 is “1”, the switch SWRef1 is turned on, with reference current IRef=IRef1. In an interval 2 for the video signal 16 to 31, the control signal Dcona2 is “1”, the switch SWRef2 is turned on, with reference current IRef=IRef2. In an interval 3 for the video signal 32 to 47, the control signal Dcona3 is “1”, the switch SWRef3 is turned on, with reference current IRef=IRef3. In an interval 4 for the video signal 48 to 63, the control signal Dcona4 is “1”, the switch SWRef4 is turned on, with reference current IRef=IRef4. In the example shown in FIG. 9, the 64 grayscales are divided into equal four intervals. However, with the present invention, the number of intervals of dividing the totality of the grayscales and the interval of the intervals may suitably be changed as necessary. Moreover, in the example shown in FIG. 9, the number of the current sources selected out of the four current sources is one, however, plural current sources may also be selected. FIG. 10 shows another illustrative structure of the reference current source circuit 12. Referring to FIG. 10, the reference current source circuit 12 is made up by one or more PMOS transistors (PMOS current sources) MRef b1 to MRef bn. The output current IRef of the reference current source circuit 12 is controlled by controlling the gate voltage (bias voltage) of the PMOS transistors MRef b1 to MRef bn. The gate voltages of the MRef b1 to MRef bn are set to the voltages of control signals Dcon b1 to Dcon bn, output from a voltage selection circuit 122. The voltage selection circuit 122 determines the voltages of the control signals Dcon b1 to Dcon bn, based on the decoded signal output from the decoder 121 supplied with the video signal. The decoder 121 and the voltage selection circuit 122 form a gate voltage control circuit 120 controlling the gate voltage based on input video signal. FIG. 11 shows an illustrative structure of the voltage selection circuit 122 of FIG. 10. Referring to FIG. 11, the voltage selection circuit 122 includes a resistor string, made up by resistors Rcon b1 to Rcon bn−1, connected in series between a high side reference potential VRCONH1 and a low side reference potential VRCONL1, reference potentials VRCONH1 and VRCONL1, junctions (taps) of resistors Rcon b1 to Rcon bn−1, and switches SWcon b1 to SWcon bn, the control terminals of which are supplied with an output signal form the decoder 121. The selection circuit selects the gate voltage needed for the current source transistors of the reference current source circuit 12, by turning the switches SWcon b1 to SWcon bn on or off, to output the selected gate voltage from the output terminals Dcon b1 to Dcon bn. FIG. 12 shows an exemplary configuration in which the 64 grayscales are partitioned equally into four intervals in the voltage selection circuit 122 of FIG. 11. The configuration shown in FIG. 12 corresponds to the configuration of FIG. 11 in which four switches SWcon b1 to SWcon b4 are used as the n switches SWcon b1 to SWcon bn and the resistor string is formed by resistors b1, b2 and b3. The taps of the resistor string, made up by resistors b1 to b3, are four junctions, that is, the high side reference potential VRCONH1, low side reference potential VRCONL1, a junction of the resistors b1 and b2, and a junction of the resistors b2 and b3. A selection circuit, made up by four switches SWcon b1 to SWcon b4, is inserted between the four taps and an output terminal Dcon b1. The selection circuit selects one of the four potentials, based on the decoded signal from the decoder 121, to output the selected potential to the output terminal Dcon b1. FIG. 13 shows an exemplary operation of the voltage selection circuit 122 of FIG. 12 (truth table). The truth table of FIG. 13 corresponds to a case in which the current source of the reference current source circuit 12 of FIG. 10 is made up by a sole transistor (PMOS transistor MRef b1 of FIG. 10). Referring to FIGS. 12 and 13, in the interval 1, out of four intervals obtained on equally dividing the 64 grayscales (0 to 63), the switch SWcon b1 is turned on, with the voltage output from the output terminal Dcon b1 being VRCONH1. In the interval 2, only the switch SWcon b2 is turned on. The voltage output from the output terminal Dcon b1 of the voltage selection circuit 122 is the voltage obtained on voltage division of the potential between the high side reference potential VRCONH1 and the low side reference potential VRCONL1 by resistance values b1 and (b2+b3), and is given by the following equation (7): Dconb1=VRCONL1+(VRCONH1−VRCONL1)×(b2+b3)/(b1+b2+b3)={VRCONH1×(b2+b3)+VRCONL1×b1}/(b1+b2+b3) (7). In the interval 3, only the switch SWcon b3 is turned on. The voltage output from the output terminal Dcon b1 of the voltage selection circuit 122 is the voltage obtained on voltage division of the potential between the high side reference potential VRCONH1 and the low side reference potential VRCONL1 by resistance values (b1+b2) and b3, and is given by the following equation (8): Dconb1=VRCONL1+(VRCONH1−VRCONL1×b3/(b1+b2+b3)={VRCONH1×b3+VRCONL1×(b1+b2)}/(b1+b2+b3) (8). In the interval 4, only the switch SWcon b4 is turned on. The voltage output from the output terminal Dcon b1 of the voltage selection circuit 122 is given by the low side reference potential VRCONL1. In FIGS. 11 and 12, the configuration of the voltage selection circuit 122, in which the tap voltage of the resistor string is selected by a switch forming the selection circuit, and output, has been explained. The present invention is, however, not limited to this configuration. For example, the reference current, output from the reference current source circuit 12, may be changed by memorizing data of voltage values in a memory, not shown, accessing a memory, based on video signal or decoded results by the decoder 121 of the video signal, to read out voltage value data, and by selecting or converting the corresponding analog voltage, based on voltage value data, to control the gate voltage of the current source transistor (PMOS transistor MRef b1 of FIG. 10). The configuration of the second current driver circuit 11 of the present embodiment, shown in FIG. 1, is now described. FIG. 14 shows an exemplary configuration of the second current driver circuit 11 of FIG. 1. The second current driver circuit 11 makes corrections to cause the input/output characteristic of the output current of the driver circuit for a light-emitting element of the 2k grayscales to approach to the gamma characteristic. Referring to FIG. 14, the second current driver circuit 11 includes a decoder 111 for being supplied with and decoding the video signal, current sources (PMOS current sources) IDel 1 to IDeln, having one ends connected to the potential VPCON, and switches SWDel1 to SWDeln, connected between the output ends of the current sources IDel 1 to IDeln and the output terminal 113 and having control terminals supplied with control signals DDel1 to DDeln from the decoder 111. The second current driver circuit also includes current sources (NMOS current sources) IAdd1 to IAddn having one ends connected to the potential VNCON, and switches SWAdd1 to SWAddn connected between output ends of the switches SWAdd1 to SWAddn and the output terminal 113 and having control terminals supplied with the control signals DAdd1 to DAddn from the decoder 111. The PMOS current sources IAdd1 to IAddn supplying the source current to the output terminal 113 and NMOS current sources IDel 1 to IDeln, supplying the sink current to the output terminal 113, are the current sources for addition and subtraction, respectively. The switches SWAdd1 to SWAddn and SWAdd1 to SWAddn control the current sources for addition and for subtraction, and the values of the currents flowing through the current sources are adjusted from the outset so as to match to the gamma characteristic. In FIG. 14, the output terminal 113 is connected to the output terminal 2 of FIG. 1. FIG. 15 shows an exemplary structure in which only the current source for addition is used in the second current driver circuit 11 of FIG. 14. FIG. 16 depicts a truth table for explaining the operation of the decoder 111 of FIG. 15 in case 64 grayscales are equally divided into four intervals. Referring to FIG. 15, the second current driver circuit 11 includes a decoder 111, which receives and decodes the video signal, a plurality of current sources (NMOS current sources) IAdd1 to IAdd3, having one ends connected to the potential VNCON and a plurality of switches SWAdd1 to SWAdd3 connected between the output ends of the current sources IAdd1 to IAdd3 and the output terminal 113 and having control terminals supplied with the control signals DAdd1 to DAddn from the decoder 111. The NMOS current sources IAdd1 to IAdd3, supplying the sink current IOUT2 to the output terminal 113, represent current sources for addition and control the switches SWAdd1 to SWAdd3 on or off with the control signals DAdd1 to DAddn to variably control the current value. Referring to FIGS. 15 and 16, the control signals DAdd1 to DAdd3 are “0”, the switches SWAdd1 to SWAdd3 are all off and the second output current IOUT2 is 0 uA, in the second current driver circuit 11, for the domain of the video signal of 0 to 15. The output current IOUT is supplied from the first output current IOUT1 of the first current driver circuit 10. In the interval 2, with the video signal from 16 to 31, the control signal DAdd1 is “1”, the switch SWAdd1 is on and the second output current IOUT2 is IAdd1. In the interval 3, with the video signal from 32 to 47, the control signal DAdd1 is “1”, the switch SWAdd2 is on and the second output current IOUT2 is IAdd2. In the interval 4, with the video signal from 48 to 63, the control signal DAdd3 is “1”, the switch SWAdd3 is on and the second output current IOUT2 is IAdd3. If, in the interval 1, the video signal is 15, the switches SW1 to SW4 (see FIG. 1) in the first current driver circuit 10 are all on, while the control signal Dcona1 of the reference current source circuit 12 (see FIG. 8) is on (see FIG. 9), so that the first output current IOUT1=15×IRef1, where IRef1 is the current value of the current source IRef1 of the reference current source circuit 12, is output from the first current driver circuit 10. If, in the interval 2, the video signal is 16, the switches SW1 to SW4 (see FIG. 1) in the first current driver circuit 10 are all off, while the first output current IOUT1 of the first current driver circuit 10 is 0 uA. In the interval 2, the switch SWAdd1 of the second current driver circuit 11 is on, as aforesaid, while the second output current IOUT2 is IAdd1. Thus, in the present embodiment, the current IOUT2=IAdd1=16×IRef1 (9) is output, so that the output current IOUT of the driver circuit for a light-emitting element is IOUT=IOUT1+IOUT2=16×IRef1 (10) where IRef1 is the current value of the current source IRef1 of the reference current source circuit 12 of FIG. 8. That is, in the present embodiment, the current of the current source IAdd1 of the second current driver circuit 11 (see FIG. 15) is set to 16 times as large as the current value of the current source IRef1 of the reference current source circuit 12 of FIG. 8. With the video signal 17, the switch SW1 out of the switches SW1 to SW4 (see FIG. 1) in the first current driver circuit 10 is turned on, the first output current IOUT1 is 20×IRef1, the control signal Dcon a2 of the reference current source circuit 12 (see FIG. 9) is “1”, the switch SWAdd1 in the second current driver circuit 11 is turned on, the second output current IOUT2 is IAdd1 and the output current IOUT is i×IRef1+IAdd1 (11) In similar manner, the output current IOUT is i×IRef3+IAdd2 for the interval 3, where i is an integer from 0 to 15, and is i×IRef4+IAdd3 for the interval 3, where i is an integer from 0 to 15. FIG. 16 shows the truth table of the second current driver circuit 11 performing the function of upper j bits. By a configuration in which the current is added or subtracted using the current source for correction (that is, using an NMOS current source for addition and a PMOS current source for subtraction), the gamma characteristic may be realized to higher accuracy. FIG. 17 shows another illustrative configuration of the second current driver circuit 11 of FIG. 1. Referring to FIG. 17, the second current driver circuit 11 includes PMOS transistors MDel b1 to MDel bn, having sources connected in common to the potential VPCON and having gates supplied with control signals DDel b1 to DDel bn, and NMOS transistors MAddb1 to MAddbn having sources connected in common to the potential VNCON and having gates supplied with control signals DAdd b1 to DAdd bn. The drains of the NMOS transistors MAddb1 to MAddbn are connected in common to the output terminal 113. The control signals DDel b1 to DDel bn and the control signals DAdd b1 to DAdd bn are output from a voltage selection circuit 112. This voltage selection circuit 112 outputs control signals DDel b1 to DDel bn and the control signals DAdd b1 to DAdd bn, based on the decoded signal from the decoder 111, configured for being supplied with and decoding the video signal. The decoder 111 and the voltage selection circuit 112 make up a gate voltage controlling circuit 110. In the configuration shown in FIG. 14, the second current driver circuit 11 controls the second output current IOUT2 by the switches SWDel1 to SWDeln and the switches SWAdd1 to SWAddn. In the configuration shown in FIG. 17, the current value of the second output current IOUT2 is variably controlled by controlling the gate voltage of the transistors of the PMOS and NMOS current sources. In the configuration shown in FIG. 14, plural current sources are needed. In the configuration shown in FIG. 17, configured for variably controlling the output current by varying the gate voltage, the current source transistor is formed by a sole transistor, thereby further reducing the circuit size. FIG. 18 shows an illustrative configuration of the voltage selection circuit 112 of FIG. 17. In FIG. 18, the voltage selection circuit 112 includes resistors Rcon Add1, Rcon Del1 (not shown), Rcon Add2 (not shown), Rcon Del2 (not shown) to Rcon Addn-1, Rcon Deln-1 (not shown), Rcon Addn, totaling at 2×n−1, connected in series with one another between the high side reference potential VRCONH1 and the low side reference potential VRCONL1. To the output terminal DDel b I are connected the potential VRCONH2, a junction between resistors Rcon Del1 and Rcon Add2 and a junction between resistors Rcon Deln-1 and Rcon Addn via switches SWDel b1, SWDel b2 to SWDel bn. To the output terminal DAdd b1 are connected a junction between resistors Rcon Add1 and Rcon Del1, a junction between resistors Rcon Addn-1 and Rcon Deln-1 and the potential VRCONH2 via switches SWAdd b1, SWAdd b2 and SWAdd bn. By turning the SWAdd b1 to SWDel bn on or off, the gate voltage as needed is selected by the power supply transistors MDel b1, MDel bn and MAdd bn of the second current driver circuit 11, and output at output terminals DDel b1 to DAdd b1. Or, the voltage values may be stored in a memory, not shown, and the information is invoked to control the transistor gate voltage. FIG. 19 shows another illustrative configuration of the second current driver circuit 11 of FIG. 1. Referring to FIG. 19, the PMOS current sources MDel b1 to MDel bn of FIG. 17 are omitted and only the NMOS transistor MAdd b1 is provided. The voltage selection circuit 112 sends the control signal DAdd b1 to the gate of the NMOS transistor MAdd b 1. FIG. 20 shows the configuration of the voltage selection circuit 112 of FIG. 19. Referring to FIG. 20, the voltage selection circuit 112 includes a resistor string, made up by three resistors c1 to c3, connected in series between the high side reference potential VRCONH2 and the low side reference potential VRCONL2. To the output terminal DAdd b1 are connected the potential VRCONH2, a junction between the resistors c1 and c2 and the potential VRCONL2, via switches SWAdd b1, SWAdd b2 and SWAdd b3. FIG. 21 is a truth table for illustrating the operation of the voltage selection circuit 112 in case 64 grayscales are equally divided into four intervals (see FIG. 20). In the interval 1, in the voltage selection circuit 112 in FIG. 20, the switch SWAdd b1, out of the switches SWAdd b1 to SWAdd b4, is turned on, with the DAdd b1 being VECONH2. In the interval 2, the switch SWAdd b2, out of the switches SWAdd b1 to SWAdd b4, in the voltage selection circuit 112 in FIG. 20, is turned on, with the DAdd b1 being DAddb1=VRCONL2+(VRCONH2−VRCONL2)×c3/(c1+c2+c3)={VRCONH2×(c2+c3)+VRCONL2×c}/(c1+c2+c3) (12). In the interval 3, the switch SWAdd b3, out of the switches SWAdd b1 to SWAdd b4, in the voltage selection circuit 112 in FIG. 20, is turned on, with the DAdd b1 being DAdd b1=VRCONL2+(VRCONH2−VRCONL2)×(c2+c3)/(c1+c2+c3)={VRCONH2×c3+VRCONL2×(c1+c2)}/(c1+c2+c3) (13). In the interval 4, the switch SWAdd b3, out of the switches SWAdd b1 to SWAdd b4, in the voltage selection circuit 112 in FIG. 20, is turned on, with the DAdd b1 being VRCONL2. In FIG. 21, there is shown a truth table of the second current driver circuit 11 performing the function of upper j bits. It is noted that gamma characteristics may be achieved to higher accuracy by using a current source for correction (an NMOS current source for addition and a PMOS current source for subtraction) and adding/subtracting the current. The panel luminance adjustment circuit 14 of FIG. 1 is now explained. This panel luminance adjustment circuit 14 controls the reference current source circuit 12, and the source potential of the PMOS and NMOS current sources of the second current driver circuit, by a luminance adjustment signal entered via a terminal. In general, in case a MOS transistor is used as a current source, the saturation domain of the transistor is used. The drain current in the MOS transistor is expressed by ID=β{VGS−VT}2 (14). In the above equation, ID is the drain current, β is the gain coefficient, β=μCoxW/L, where μ is the mobility of electrons, Cox is the gate capacitance per unit, W is a channel width, L is a channel length, VGS is a source to gate voltage and VT is a threshold voltage. It is seen from the above equation (14) that, if the gate-to-source voltage VGS of the MOS transistor is changed, the value of the current ID flowing through the MOS transistor is changed. If the panel luminance adjustment signal is given as a voltage value and may directly be supplied as the source voltage of the PMOS and NMOS current sources, there is no necessity of providing the panel luminance adjustment circuit 14 of FIG. 1. If the panel luminance adjustment signal is given as a digital signal, it is necessary to provide a voltage converter circuit for converting the digital luminance adjustment signal to a voltage to output the so generated voltage. For example, the panel luminance adjustment circuit 14 is constructed by a circuit shown e.g. in FIG. 18. It is noted that the video signal of FIG. 18 is a panel luminance adjustment signal, while the output signals DDelb1 and DAddb1 are the source potential VPCON of the PMOS power supply and the source potential VNCON of the NMOS power supply, respectively. It is also possible to read and control the information stored in a memory, not shown, from the outset. The following Table 1 shows an example of designing specifications in which 64 grayscales have been divided into 14 intervals. This Table 1 shows a list of interval, grayscale (video signal), current values of gamma 2.2, IOUT (output current), IOUT1 (first output current), IRef (reference current) and IOUT2 (second output current). TABLE 1 Designing Example 1 Design Values INTERVAL VIDEO SIGNAL GAMMA 2.2(uA) IOUT (uA) IOUT1 (uA) IRef (uA) IOUT2 (uA) 1 0 0.00 0.00 0.00 0.000 0.000 1 0.01 0.01 0.01 0.007 2 2 0.03 0.03 0.03 0.032 3 3 0.08 0.08 0.08 0.078 4 4 0.15 0.29 0.15 0.146 5 5 0.24 0.38 0.24 0.239 6 6 0.36 0.36 0.36 0.357 7 7 0.50 0.50 0.00 0.185 0.501 8 0.67 0.69 0.19 9 0.87 0.87 0.37 8 10 1.10 1.10 0.00 0.286 1.098 11 1.35 1.38 0.29 12 1.64 1.67 0.57 13 1.96 1.96 0.86 9 14 2.30 2.30 0.00 0.425 2.303 15 2.68 2.73 0.43 16 3.09 3.15 0.85 17 3.53 3.58 1.28 18 4.00 4.00 1.70 10 19 4.51 4.51 0.00 0.606 4.509 20 5.05 5.11 0.61 21 5.62 5.72 1.21 22 6.22 6.33 1.82 23 6.86 6.93 2.42 24 7.54 7.54 3.03 11 25 8.25 8.25 0.00 0.850 8.246 26 8.99 9.10 0.85 27 9.77 9.95 1.70 28 10.58 10.80 2.55 29 11.43 11.65 3.40 30 12.32 12.50 4.25 31 13.24 13.34 5.10 32 14.19 14.19 5.95 12 33 15.19 15.19 0.00 1.181 15.189 34 16.22 16.37 1.18 35 17.29 17.55 2.38 36 18.39 18.73 3.54 37 19.54 19.91 4.72 38 20.72 21.09 5.91 39 21.93 22.28 7.09 40 23.19 23.46 8.27 41 24.49 24.64 9.45 42 25.82 25.82 10.63 13 43 27.19 27.19 0.00 1.588 27.191 44 28.60 28.76 1.57 45 30.05 30.33 3.14 46 31.54 31.90 4.70 47 33.07 33.46 6.27 48 34.64 35.03 7.84 49 36.24 36.60 9.41 50 37.89 38.17 10.98 51 39.58 39.74 12.55 52 41.30 41.30 14.11 14 53 43.07 43.07 0.00 1.993 43.072 54 44.88 45.07 1.99 55 46.73 47.06 3.99 56 48.62 49.05 5.98 57 50.55 51.04 7.97 58 52.52 53.04 9.96 59 54.53 55.03 11.96 60 56.59 57.02 13.95 61 58.68 59.01 15.94 62 60.82 61.01 17.93 63 63.00 63.00 19.83 In the above Table 1, gamma 2.2 is the value of the gamma curve and is given by gamma 2.2=IMAX×(video signal/number of grayscales)2.2. It is noted that the IMAX of the output current IOUT is the maximum current value. In the present embodiment, gamma 2.2=63×(video signal/63 grayscales)2.2. As for the gamma characteristic, the lower the grayscale, the stronger is its curvilinear property and, the higher the grayscale, the stronger is its linearity. That is, the second output current is used from the second current driver circuit 11 for compensation at the end of the interval of linear approximation. Referring to the Table 1, the first output current IOUT1 is varied responsive to 0 to 63 grayscales. The decoder 13 of FIG. 1 decodes the totality of bits (6 bits) of the video signal to control the on/off of the switches. The reference current IRef is 0 μA for the interval 1 to 6, 0.185 μA for the interval 7 (video signal=7, 8 and 9), 0.286 μA for the interval 8 (video signal 10 to 13), 0.425 μA for the interval 9 (video signal 14 to 18), 0.606 μA for the interval 10 (video signal=19 to 24), 0.850 μA for the interval 11 (video signal 25 to 32), 1.181 μA for the interval 12 (video signal 33 to 42), 1.588 μA for the interval 13 (video signal 43 to 52), and 1.993 μA for the interval 14 (video signal 53 to 63). The second output current IOUT2 is varied to 0 μA, 0.007 μA, 0.0032 μA, 0.078 μA, 0.146 μA, 0.239 μA and to 0.357 μA for the intervals 1, 2, 3, 4, 5 and 6, respectively, and is 0.501 μA, 1.098 μA, 2.303 μA, 4.509 μA, 8.246 μA, 15.189 μA, 27.191 μA and 43.072 μA for the intervals 7, 8, 9, 10, 11, 12, 13 and 14, respectively. For example, in the interval 7, the reference current IRef is the reference current for the video signal from 7 to 9. Hence, it is sufficient if the output current IOUT of 0.87 μA flows for the grayscale 9. Consequently, the reference current IRef for the interval 7 is given by IRef f=(0.87−0.50)/2=0.185 μA (see Table 1). The gamma 2.2 for the video signal=7 for the interval 7 is 0.50 μA. Since IOUT1=0, IOUT2 is 0.501 μA, and the output current IOUT of the driver circuit for a light-emitting element is given by IOUT=IOUT1+IOUT2. As for the interval 8 ff., the reference current IRef and the second output current IOUT2 of the second current driver circuit may be found in similar manner. In the design specifications of the above Table 1, the 64 grayscales are partitioned into 14 intervals. The present invention is not limited to these specifications, such that the number of division or the interval width may, of course, be optionally set depending on the number of currents of the reference current source circuit 12, the number of current sources of the first and second current driver circuits 10, 11 or the number of grayscales. The following Table 2 is a truth table for illustrating the configuration and the operation of the reference current source circuit 12 for the realization of the designing example of the above Table 1. TABLE 2 Designing Example 1 Reference Current Source Circuit and Truth Table Reference Current Source Circuit INTERVAL VIDEO SIGNAL SWRef1 SWRef2 SWRef3 SWRef4 SWRef5 SWRef6 SWRef7 SWRef8 1 0 0 0 0 0 0 0 0 0 1 2 2 3 3 4 4 5 5 6 6 7 7 1 8 9 8 10 0 1 11 12 13 9 14 0 1 15 16 17 18 10 19 0 1 20 21 22 23 24 11 25 0 1 26 27 28 29 30 31 32 12 33 0 1 34 35 36 37 38 39 40 41 42 13 43 0 1 44 45 46 47 48 49 50 51 52 14 53 0 1 54 55 56 57 58 59 60 61 62 63 In the switches SWRef1 to SWRefn of the reference current source circuit 12 of FIG. 8, ‘n’ is set to 8, that is, eight switches are provided, and the switches SWRef1 to SWREf8 are turned on for the intervals 7 to 14. The following Table 3 is a truth table for illustrating the configuration and the operation of the first current driver circuit 10 for the realization of the designing example of the above Table 1. TABLE 3 Designing Example 1 Current Driver Circuit 10 Truth Table Current Driver Circuit 10 INTERVAL VIDEO SIGNAL SW01 SW02 SW03 SW04 SW05 SW06 SW07 SW08 SW09 SW10 1 0 0 0 0 0 0 0 0 0 0 0 1 2 2 3 3 4 4 5 5 6 6 7 7 8 1 9 1 8 10 0 0 11 1 12 1 13 1 9 14 0 0 0 15 1 16 1 17 1 18 1 10 19 0 0 0 0 20 1 21 1 22 1 23 1 24 1 11 25 0 0 0 0 0 26 1 27 1 28 1 29 1 30 1 31 1 32 1 12 33 0 0 0 0 0 0 0 34 1 35 1 36 1 37 1 38 1 39 1 40 1 41 1 42 1 13 43 0 0 0 0 0 0 0 0 0 44 1 45 1 46 1 47 1 48 1 49 1 50 1 51 1 52 1 14 53 0 0 0 0 0 0 0 0 0 54 1 55 1 56 1 57 1 58 1 59 1 60 1 61 1 62 1 63 1 The switches Sw1 to Swk of the first current driver circuit 10 of FIG. 1 are 10 switches SW01 to SW10. In the example shown in Table 3, the current source transistors M1 to M10 are not weighted. The decoder 13 is supplied with 6-bit video signal to control the on/off of the switches SW0 to SW10, for the values 1 to 63 of the video signal, as shown in Table 3. In case of weighting of the current source transistors M1 to M10, the configuration is of 4 bits. The following Table 4 is a truth table for illustrating the configuration and the operation of the second current driver circuit 11 for the realization of the designing example of the above Table 1. TABLE 4 Designing Example 1 Current Driver Circuit 11 Truth Table Current Driver Circuit 11 VIDEO SW1 SW2 SW3 SW4 INTERVAL SIGNAL 1 1 1 1 SW5 1 SW6 1 SW7 1 SW8 1 SW9 1 SW10 1 SW11 1 SW12 1 SW13 1 SW14 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 2 2 1 3 3 1 4 4 1 5 5 1 6 6 1 7 7 1 8 9 8 10 1 11 12 13 9 14 1 15 16 17 18 10 19 1 20 21 22 23 24 11 25 1 26 27 28 29 30 31 32 12 33 1 34 35 36 37 38 39 40 41 42 13 43 1 44 45 46 47 48 49 50 51 52 14 53 1 54 55 56 57 58 59 60 61 62 63 The switches SWAdd1 to SWAdd3 of the second current driver circuit 11 of FIG. 15 are 14 switches of SW11 to SW141. The decoder 111 performs on/off control of the switches SW11, SW21, SW31, . . . , SW141, for the video signal 1 to 63, as shown in Table 4. The following Table 5 shows another example of the designing specifications in case 63 grayscales are partitioned into 14 intervals. This Table 5 shows a list of the interval, grayscale (video signal), current values of gamma 2.2, IOUT (output current), IOUT1 (first output current), reference current IRef and IOUT2 (second output current). TABLE 5 Designing Example 2 Design Values INTERVAL VIDEO SIGNAL GAMMA 2.2(uA) IOUT (uA) IOUT1 (uA) IRef (uA) IOUT2 (uA) 1 0 0.00 0.00 0.00 0.000 0.000 1 0.01 0.01 0.01 0.007 2 2 0.03 0.03 0.03 0.032 3 3 0.08 0.08 0.08 0.078 4 4 0.15 0.29 0.15 0.146 5 5 0.24 0.39 0.24 0.239 6 6 0.36 0.36 0.36 0.357 7 7 0.50 0.50 0.00 0.185 0.501 8 0.67 0.69 0.19 9 0.87 0.87 0.37 8 10 1.10 1.10 0.00 0.286 1.098 11 1.35 1.38 0.29 12 1.64 1.67 0.57 13 1.96 1.96 0.86 9 14 2.30 2.30 0.00 0.425 2.303 15 2.68 2.73 0.43 16 3.09 3.15 0.85 17 3.53 3.58 1.28 18 4.00 4.00 0.00 1.700 10 19 4.51 4.51 0.00 0.606 4.509 20 5.05 5.11 0.61 21 5.62 5.72 1.21 22 6.22 6.33 1.82 23 6.86 6.93 0.00 2.423 24 7.54 7.54 0.61 11 25 8.25 8.25 0.00 0.850 8.246 26 8.99 9.10 0.85 27 9.77 9.95 1.70 28 10.58 10.80 2.55 29 11.43 11.65 0.00 3.399 30 12.32 12.50 0.85 31 13.24 13.34 1.70 32 14.19 14.19 2.55 12 33 15.19 15.19 0.00 1.181 15.189 34 16.22 16.37 1.18 35 17.29 17.55 2.36 36 18.39 18.73 3.54 37 19.54 19.91 0.00 4.725 38 20.72 21.09 1.18 39 21.93 22.28 2.36 40 23.19 23.46 3.54 41 24.49 24.64 0.00 4.725 42 25.82 25.82 1.18 13 43 27.19 27.19 0.00 1.568 27.191 44 28.60 28.76 1.57 45 30.05 30.33 3.14 46 31.54 31.90 4.70 47 33.07 33.46 0.00 6.273 48 34.64 35.03 1.57 49 36.24 36.60 3.14 50 37.89 38.17 4.70 51 39.58 39.74 0.00 6.273 52 41.30 41.30 1.57 14 53 43.07 43.07 0.00 1.993 43.072 54 44.88 45.07 1.99 55 46.73 47.06 3.99 56 48.62 49.05 5.98 57 50.55 51.04 0.00 7.971 58 52.52 53.04 1.99 59 54.53 55.03 3.99 60 56.59 57.02 5.98 61 58.68 59.01 0.00 7.971 62 60.82 61.01 1.99 63 63.00 63.00 3.99 In the above Table 5, gamma 2.2 is the value of the gamma curve and is given by gamma 2.2=IMAX×(video signal/number of grayscales)2.2. It is noted that the IMAX of the output current IOUT is the maximum current value. In Table 5, the reference current IRef for the intervals 1 to 14 is the same as in Table 1 above. In the example of Table 5, the first output current IOUT1 assumes ten different values at the maximum in each interval. The decoder 13 of the first current driver circuit 10 is of the 3-bit configuration (with there being current source weighting), and compensation is by the second output current from the second current driver circuit 11 at an end of each interval. That is, the carry current of the first current driver circuit 10 is taken charge of by the second current driver circuit 11. Table 6 is a truth table for illustrating the operation of the first current driver circuit 10 for realization of the designing example of Table 5. TABLE 6 Designing Example 2 Current Source Driver Circuit 10 Truth Table Current Source Driver Circuit 10 INTERVAL VIDEO SIGNAL SW01 SW02 SW03 1 0 0 0 0 1 2 2 3 3 4 4 5 5 6 6 7 7 0 0 0 8 1 9 1 8 10 0 0 0 11 1 12 1 13 1 9 14 0 0 0 15 1 16 1 17 1 18 0 0 0 10 19 0 0 0 20 1 21 1 22 1 23 0 0 0 24 1 11 25 0 0 0 26 1 27 1 28 1 29 0 0 0 30 1 31 1 32 1 12 33 0 0 0 34 1 35 1 36 1 37 0 0 0 38 1 39 1 40 1 41 0 0 0 42 1 13 43 0 0 0 44 1 45 1 46 1 47 0 0 0 48 1 49 1 50 1 51 0 0 0 52 1 14 53 0 0 0 54 1 55 1 56 1 57 0 0 0 58 1 59 1 60 1 61 0 0 0 62 1 63 1 In Table 6, the switches SW01, SW02 and SW03 of the first current driver circuit 10 correspond to the switches SW1, SW2 and SW3 (k=3), respectively. The current source transistors M1, M2 and M3 (k=3) are weighted with 20, 21, 22, respectively. The following Table 7 is a truth table for illustrating the configuration and the operation of the second current driver circuit 11 for the realization of the designing example of the above Table 5. In the Table 7, 0 and 1 denote off and on, respectively. TABLE 7 Designing Example 2 Current Driver Circuit 11 Truth Table 1 Current Driver Circuit 11 VIDEO SW1 SW2 INTERVAL SIGNAL 1 1 SW3 1 SW4 1 SW5 1 SW6 1 SW7 1 SW8 1 SW9 1 SW9 2 SW10 1 SW10 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 2 2 1 3 3 1 4 4 1 5 5 1 6 6 1 7 7 1 8 9 8 10 1 11 12 13 9 14 1 15 16 17 18 1 10 19 1 20 21 22 23 1 24 11 25 26 27 28 29 30 31 32 12 33 34 35 36 37 38 39 40 41 42 13 43 44 45 46 47 48 49 50 51 52 14 53 54 55 56 57 58 59 60 61 62 63 The switches SWAdd1 to SWAdd3 of the second current driver circuit 11 of FIG. 15 are 12 switches of SW11, SW21, SW31, SW41, SW51, SW61, SW71, SW81, SW91, SW101 and SW102. The decoder 111 is supplied with and decodes 6-bit video signal and on/off controls the switches SW11, . . . , SW102, as shown in Table 7. The following Table 8 is a truth table for illustrating the configuration and the operation of a modified configuration of the second current driver circuit 11 for the realization of the designing example of the above Table 5. In the Table 7, 0 and 1 denote off and on, respectively. TABLE 8 Designing Example 2 Current Driver Circuit 11 Truth Table 2 Current Driver Circuit 11 INTERVAL VIDEO SIGNAL SW11 1 SW11 2 SW12 1 SW12 2 SW12 3 SW13 1 SW13 2 SW13 3 SW14 1 SW14 2 SW14 3 1 0 0 0 0 0 0 0 0 0 0 0 0 1 2 2 3 3 4 4 5 5 6 6 7 7 8 9 8 10 11 12 13 9 14 15 16 17 18 10 19 20 21 22 23 24 11 25 1 26 27 28 29 1 30 31 32 12 33 1 34 35 36 37 1 38 39 40 41 1 42 13 43 1 44 45 46 47 1 48 49 50 51 1 52 14 53 1 54 55 56 57 1 58 59 60 61 1 62 63 A display device according to the present invention will be described next. FIG. 22 is a diagram illustrating an implementation in which a display driver according to the present invention is applied to a display device of active-matrix drive type. The display panel 200 includes light-emitting units ER, EG and EB for emitting red, green and blue light, respectively, arrayed at the intersections of a plurality (n-number) of horizontal scan lines A1 to An of one screen and m-number of red drive data lines DR1 to DRm, m-number of green drive data lines DG1 to DGm and m-number of blue drive data lines DB1 to DBm disposed so as to intersect each of the scan lines. The light-emitting units comprise electroluminescent elements, by way of example. Responsive to a video signal input thereto, a timing signal generating circuit 203 generates a timing signal, which indicates the application timing of scan pulses applied sequentially to the scan lines A1 to An, and supplies the signal to a scan driver 202. The scan driver 202 supplies the scan lines A1 to An of the display panel with scan pulses sequentially responsive to the timing signal supplied from the timing signal generating circuit 203. The data driver 201 generates a current that corresponds to the logic level of the video signal and drives the drive data lines DR1 to DRm, DG1 to DGm and DB1 to DBm. FIG. 23 is a block diagram illustrating the structure of the data driver 201 shown in FIG. 22. As shown in FIG. 23, the data driver 201 has a shift register 211, a data register 212, a latch circuit 213 and an output circuit 214. Signals input to the shift register 211, etc., are a synchronising clock signal CLK, a start-pulse signal STH and a latch signal (strobe signal) STB supplied by the timing signal generating circuit 203. The video signal is input to the data register 212 and the panel-luminance adjustment signal is input to the output circuit 214. The output circuit 214 has a plurality (m×3) of driver circuits 215, which are for driving light-emitting elements, having output terminals connected to respective ones of m-number of red, green and blue drive data lines. Each driver circuit 215 is constituted by the light-emitting-element driver circuit embodying the present invention described above with reference to FIG. 1, etc. The shift register 211 transfers the strobe signal STB, which is supplied by the start pulse STH constituting the start timing of the horizontal scanning interval, in accordance with the clock signal CLK and supplies the strobe signal successively to the data register 212. The data register 212 samples the video signal in response to the strobe signal from the shift register 211 and transfers the video signal to the latch circuit 213. The latch circuit 213 latches a plurality of video signals, which have been latched by the data register 212, all at once in response to the strobe signal STB and supplies the latched signals to the corresponding element driver circuits 215. The video signal supplied to the input terminal 1 in FIG. 1 is the signal latched by the latch circuit 213. The element driver circuit 215 also performs a gamma correction of gamma value 2.2, etc. Further, the element driver circuit 215 receives an input of the panel-luminance adjustment signal and performs an overall luminance adjustment of the display panel 200. The light-emitting units ER, EG and EB for emitting red, green and blue light, respectively, are not identical with one another in terms of the relationship between the current that flows and luminance. Accordingly, in the present embodiment, the current supplied from each of the element driver circuits 215 is adjusted beforehand on a per-color basis, whereby panel luminance can be made uniform. Specifically, in the present embodiment, the element driver circuits 215 are controlled individually depending upon the color of the light-emitting element, whereby the luminance of the panel is made uniform. Since each element driver circuit 215 performs a gamma correction internally of the driver circuit, it is unnecessary to provide a gamma correction circuit and chip area is reduced in a case where integration is performed. The circuit therefore is well suited for application to a semiconductor device. The driver circuit for a light-emitting element illustrated in FIG. 1 can be construed as having the structure of a current-output-type digital-to-analog converter (DAC) circuit for performing a non-linear conversion such as a gamma correction. That is, a DA converter, supplied with a digital input signal and outputting an output current converted from and corresponding to the digital input signal, includes the first current driver circuit 10, second current driver circuit 11 and the reference current source circuit 12. The first current driver circuit includes plural current sources, output current values of which are determined based on the reference current IRef, and a switch circuit for on/off controlling the current path between the plural current sources and current output terminals, based on the digital input signal, to output a first output current IOUT1 conforming to the digital input signal. The second current driver circuit outputs a second output current IOUT2 conforming to the digital input signal, whilst the reference current source circuit, including a reference current source, generates the reference current IRef, exercises variable control based on the digital input signal. The sum current that is obtained on combining the first output current IOUT1 and the second output current IOUT2 from the first and second current driver circuits is output as the output current IOUT, while the amount of change in the output current IOUT (quantization step) corresponding to the change in the unit quantity of the digital input signal (1 LSB) is varied responsive to the value (interval) of the digital input signal. Of course, it may be so arranged that current that is output from the converter circuit is converted to a voltage and the driver circuit outputs a voltage conforming to the input voltage, whereby a voltage-drive-type display element such as a liquid crystal element is driven by a data signal that has been gamma-corrected in accordance with the grayscale. The input/output characteristic between the input signal and the output current can be set to a gamma characteristic having two inflection points (points where the polarity of curvature reverses). It is also possible with the present invention to set the input/output characteristic between the input signal and the output current to a desired characteristic depending on the number of the current sources of the first and second current driver circuits and the reference current source circuit, the setting of the current values thereof and on the manner of bit allocation of the input signal. Although the present invention has so far been explained with reference to preferred embodiments thereof, it is to be noted that these embodiments are merely illustrative and the present invention encompasses various changes or corrections that may be within the reach of those skilled in the art within the scope of the invention as defined in the claims. It should be noted that other objects, features and aspects of the present invention will become apparent in the entire disclosure and that modifications may be done without departing the gist and scope of the present invention as disclosed herein and claimed as appended herewith. Also it should be noted that any combination of the disclosed and/or claimed elements, matters and/or items may fall under the modifications aforementioned. | <SOH> BACKGROUND OF THE INVENTION <EOH>An arrangement of the kind illustrated in FIG. 25 by way of example is known as an electroluminescent storage device (refer to the specification of Japanese Patent Kokai Publication No. JP-A-2-14868 pages 5 and 6, FIG. 2 ). As shown in FIG. 25 , this conventional electroluminescent device includes an electroluminescent element 40 ; a plurality of memory cells 22 corresponding to the electroluminescent element 40 ; a current source 28 (a current mirror comprising transistors 26 and 27 ); current control means (transistors) 24 , which correspond to the plurality of memory cells 22 , connected to corresponding ones of the memory cells 22 and responsive to signals, which are held in the memory cells 22 , for controlling current that flows from the current source 28 to the electroluminescent element 40 ; and control logic, a column data register, display input/readout logic and row strobe register, etc., none of which are shown, for supplying the memory cells 22 with signals Bn to B 0 representing luminance required by the electroluminescent element 40 . Current corresponding to the signals held in the memory cells 22 flows through transistors 24 n to 24 n - 3 , current that is the sum of the currents that flow through the transistors 24 n to 24 n - 3 enters the drain of the transistor 26 constituting the input end of the current source (current mirror) 28 , and the mirror current of the input current is output from the drain of the transistor 27 , which constitutes the output end of the current source (current mirror), and is supplied to the electroluminescent element 40 . In the arrangement shown in FIG. 25 , the relationship between the input data signal and the output current (and therefore luminance) is a positive proportional relationship (gamma value=1.0). Consequently, in order to perform a correction such as one where the gamma value is 2.2, the gamma correction must be applied to the video signal stored in the memory cells 22 . Since the human eye is sensitive to dark colors, an image will appear more natural if the luminance of the input signal satisfies a luminance=(signal strength) (e.g., γ=1.8, 2.2, etc.) relationship rather than a positive proportional relationship. In general, therefore, the relationship between panel luminance and the video signal is provided with a gamma characteristic. Generally, in a case where a gamma correction is made, as shown in FIG. 26 , a gamma correction circuit 131 for making the relationship between the input signal (video signal) and luminance conform to the gamma characteristic is provided on the input side of a display element driver circuit 132 . The signal that has been gamma-corrected by the gamma correction circuit 131 is input to the display element driver circuit 132 , and the data signal is supplied from the display element driver circuit 132 to a display element panel 133 via a data signal line. Since the gamma correction circuit 131 is necessary in this arrangement, however, not only is the circuitry large in size but an additional problem is a reduction of grayscales that can be expressed. For example, if the gamma characteristic (gamma value=2.2) is expressed using an 8-bit (256 grayscales) display element driver circuit 132 , only 187 grayscales can be realized. In order to implement a gamma correction having grayscale (256 grayscales) the same as those of the input signal, on the other hand, it is necessary that the gamma correction circuit 131 and display element driver circuit 132 be capable of supporting more grayscales than those of the input signal, as illustrated in FIG. 27 . Consequently, the circuitry is large in size. In the example illustrating in FIG. 27 , both the gamma correction circuit 131 and display element driver circuit 132 support 512 grayscales (nine bits). [Patent Document 1] Japanese Patent Kokai Publication No. JP-A-2-148687, pages 5 and 6, FIG. 2 ) Thus, in a case where the conventional display circuit is provided with a gamma correction function, a problem which arises is the large size of the circuitry, as mentioned above. The same is true also in a case where a gamma correction of grayscales identical with those of the input signal is performed. | <SOH> SUMMARY OF THE DISCLOSURE <EOH>Accordingly, it is an object of the present invention to provide a driver circuit that makes it possible to reduce the size of circuitry and diminish chip area in realizing a gamma characteristic, as well as to a display device having this driver circuit. Another object of the present invention is to provide a driver circuit that makes it possible to adjust the overall luminance of a display panel while maintaining the gamma characteristic, as well as a display device having this driver circuit. The above and other objects are attained by the present invention, which enables optimum display by varying the reference current, flowing through a reference current source circuit, based on a video signal, for approximating the input/ output characteristic of the EL element driver circuit to e.g. the gamma characteristic. More specifically, the reference current prescribes the amount of change in the output current corresponding to a unit change of the input signal A driver circuit in accordance with one aspect of the present invention, includes a reference current source circuit for varying the value of the reference current based on the input signal; and an output current generating circuit for generating the output current conforming to the input signal based on the reference signal to output the output current at the output terminal, wherein a characteristic between the input signal that is input to an input terminal and the output current that is output from the output terminal is made a predetermined input/output characteristic of a prescribed non-linearity. In the present invention, the input signal is a digital signal, and a unit change of the input signal corresponds to a one bit equivalent which is the least significant bit (LSB) of the digital signal. In the present invention, the input signal is a digital signal, and the output current generating circuit includes a first current generating circuit for generating a first output current corresponding to the input signal based on the reference current source, and a second current generating circuit for generating a second output current corresponding to the input signal from a current source distinct from the reference current source. A current, that is the result of combining (adding or subtracting) the first output current and the second output current is output as the output current from the output terminal. A range of the input signal from a minimum value to a maximum value is divided into plural intervals, and the first output current is zero at one end of one such interval, with the second output current being the aforementioned output current output from the output terminal. According to the present invention, the current value of the output current at least one of the leading end and the trailing end of said interval of the input signal is set to a current value corresponding to a theoretical (ideal) value of an input/output characteristic of predetermined non-linearity and linear approximation of the non-linear input/output characteristic is performed from one interval to the next. In another aspect, the present invention provides a driver circuit for a light-emitting element in which a light emitting element, having light emission controlled responsive to the current supplied, receives a video signal input via an input terminal, to generate the current corresponding to the video signal, to output the current thus generated at an output terminal, in which the driver circuit for a light-emitting element comprises a decoder supplied with the video signal composed of plural bits to decode the video signal thus supplied, a first current driver circuit including a plurality of current sources, the current value in each of which is prescribed based on the value of a given reference current, and a switch circuit for on/ off control of a current path between the plural current sources and a current output terminal, based on an output signal of the decoder, to output a first output current conforming to the value of the video signal. The driver circuit for a light-emitting element also comprises a second current driver circuit outputting a second output current conforming to the value of the video signal, and a reference current source circuit having a reference current source outputting the reference current, with the reference current source circuit variably controlling the reference current output based on the value of the video signal. A current that is the result of combining the first and second output currents from the first and second current source circuits is output at the output terminal as an output current, and the amount of change in the output current corresponding to a change in a unit quantity of the video signal is varied responsive to the video signal. In another aspect, the present invention provides a driver circuit for a light-emitting element in which a luminance adjustment signal is used to control the current source to adjust the luminance of the light emitting element. More specifically, the present invention preferably includes a luminance adjustment circuit for variably generating the control voltage based on an input control signal. The output current value of the output reference current, output by the reference current source circuit, is changed based on the control voltage. According to the present invention, the second current driver circuit varies the current value of the output current based on the control voltage. According to the present invention, the second current driver circuit includes a multi-output current mirror circuit supplied with the reference current at an input end for outputting the output current, which is a turned versions of the reference current, from plural outputs thereof, and a plurality of switch elements receiving signals obtained on decoding the video signal by the decoder at control terminals thereof, with the switch elements having one ends connected to the plural output ends of the current mirror circuit and having the other ends connected in common to the current output ends. According to the present invention, the reference current source circuit includes a plurality of current sources having one ends connected in common to a first potential, a decoder for the reference current source circuit, supplied with and decoding the video signal to output decoded results, and a plurality of switch elements having one ends connected to output ends of the plural current sources and having the other ends connected in common to a reference current output ends outputting the reference current. The switch elements are controlled on or off based on a signal output from the decoder for the reference current source circuit. According to the present invention, the reference current source circuit includes one or more current sources having one end connected to a first potential and having each output end connected to a current output end outputting the reference current, a decoder for the reference current source circuit, supplied with and decoding the video signal to output decoded results, and a voltage selection circuit supplying a bias current to the one or more current sources, based on decoded results by the decoder for the reference current source circuit. The current source(s) vary the output current of the current source(s) responsive to the bias current. According to the present invention, the second current driver circuit includes a decoder for the second current driver circuit supplied with and decoding the video signal to output decoded results, a first set of current sources, having one ends connected in common to a first potential, and a first set of switch devices having one ends connected to output ends of the current sources of the first set and having the opposite ends connected in common to the current output end. The switch devices of the first set, receiving a signal of the decoder for the second current driver circuit at control terminals thereof, are thereby turned on or off. According to the present invention, the second current driver circuit includes a second set of current sources, having one ends connected in common to a second potential, and a second set of switch devices having one ends connected to output ends of the current sources of the second set and having the opposite ends connected in common to the current output end. The switch devices of the second set, receiving a signal of the decoder for the second current driver circuit at control terminals thereof, are thereby turned on or off. According to the present invention, the second current driver circuit includes a decoder for the second current driver circuit supplied with and decoding the video signal to output decoded results, one or more current sources having one end(s) connected to a first potential and having output end(s) connected to a current output end outputting the second output current, and a voltage selection circuit for supplying a bias voltage to the one or more current source(s), based on the decoded results by the decoder for the second current driver circuit. The current source(s) vary an output current from the output end of the current source(s) responsive to the bias voltage. According to the present invention, the control voltage, output from the luminance adjustment circuit, is supplied as the first potential and/or the second potential of the second current driver circuit. The meritorious effects of the present invention are summarized as follows. According to the present invention, it is possible to reduce the circuit scale of the driver circuit for a light-emitting element having a gamma characteristic and to reduce the chip area. In accordance with the present invention, the overall luminance of a panel can be adjusted while maintaining the gamma characteristic. Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description in conjunction with the accompanying drawings wherein only the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of carrying out this invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawing and description are to be regarded as illustrative in nature, and not as restrictive. | 20050121 | 20090127 | 20050721 | 64436.0 | 0 | VU, JIMMY T | DRIVER CIRCUIT FOR LIGHT EMITTING ELEMENT | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,220 | ACCEPTED | Method and device for connecting parts of an exhaust gas system | A method and a device for connecting parts of an exhaust gas system which comprises at least one metal tube formed from a bellows and optionally further parts disposed coaxially within and/or outside of the bellows and at least one further system part to be connected to the metal tube, are characterized in that one end of a short connecting tube is inserted positively in an end of the metal tube and the other end is inserted positively in the system part to be connected to the metal tube, and the system part is moved to the end of the metal tube facing the system part, thereby leaving an axial gap, and the system part, the connecting tube and the metal tube being connected from the outside in one working step. | 1. A device for connecting together parts of an exhaust gas system, the device comprising: at least one metal tube having a bellows and optional additional components disposed inside and/or outside of and coaxially to the bellows; a short connecting tube having a first end for insertion, in positive fit, into a first end of said metal tube; at least one further system part to be connected to the metal tube, said further system part accepting, in positive fit, a second end of said short connecting tube to position said system part proximate said metal tube for defining an axial gap between said system part and said metal tube; and means for connecting together said system part, said connecting tube, and said metal tube, from an outside thereof, in one single processing step. 2. The device of claim 1, wherein said connecting means define one single seam spanning said axial gap. 3. The device of claim 2, wherein said seam extends over an entire periphery of said connecting tube in a region of said axial gap. 4. The device of claim 2, wherein seam is a weld seam. 5. The device of claim 4, wherein said weld seam has a specified fusion penetration in said metal tube, said connecting tube, and said further system part. 6. The device of claim 2, wherein said first and said second end of said connecting tube have different cross-sections for adaptation to different cross-sectional combinations between said metal tube and said system part. 7. The device of claim 2, wherein at least one of two facing cross-sections of said metal tube and said system part is circular. 8. The device of claim 7, wherein both facing cross-sections of said metal tube and said system part are circular. 9. The device of claim 8, wherein said two facing cross-sections of said metal tube and said system part have identical diameters. 10. The device of claim 8, wherein said two facing cross-sections of said metal tube and said system part have different diameters. 11. The device of claim 9, wherein said connecting tube is formed as a hollow cylinder with circular cross-section. 12. The device of claim 10, wherein said second end of said connecting tube has a second outer diameter corresponding to an inner diameter of said system part and said first end of said connecting tube has a first outer diameter corresponding to an inner diameter of said first end of said metal tube, wherein a transition between said first and said second outer diameters of said connecting tube to a central region of said connecting tube is continuous. 13. The device of claim 12, wherein said transition of said connecting tube has a shape of a truncated conical central region. 14. The device of claim 2, wherein said connecting-tube has an axial length to project by an amount past an end of said system part on a side of said system part facing away from said metal tube. 15. The device of claim 14, wherein said projecting amount approximately corresponds to a thickness of a seal to be used between said system part and a counter piece. 16. The device of claim 15, wherein said seal to be used between said system part and said counter piece is centered by said projecting end of said connecting tube. 17. The device of claim 15, wherein said projecting amount of said connecting tube is selected such that said counter piece is centered thereby. 18. The device of claim 2, wherein said system part is formed as a connecting flange. 19. The device of claim 18, further comprising a counter piece cooperating with said connecting flange, said counter piece defining a counter flange. 20. The device of claim 15, wherein said seal is formed as a flat seal. 21. The device of claim 2, wherein said metal tube comprises, at least one of a woven jacket disposed outside of said bellows, an agraff-liner disposed inside said bellows, and an angle flange. | This is a continuation of application Ser. No. 10/298,662 filed Nov. 19, 2002 and also claims Paris Convention priority of DE 101 58 877.1 filed Nov. 30, 2001 the complete disclosures of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION The invention concerns a method and a device for connecting parts of an exhaust gas system using at least one metal tube formed from a bellows and optionally further parts which are disposed coaxially inside and/or outside of the bellows, and at least one further system part to be connected to the metal tube. In exhaust gas systems, in particular for motor vehicles, metal tubes are conventionally used having a woven jacket, a bellows disposed therein, an agraff-inliner, and optional further equipment. They are preferably used for tube-tube connections. A part of the exhaust gas system, e.g. a tube, is thereby inserted into the metal tube at the input and output sides and welded thereto. A special variant of this type of connection is a flange connection structure wherein at least one end of the metal tube is provided with a system part which is configured as a connecting flange and which can be connected to the exhaust gas system at an existing point of separation. To join the connection flange to the metal tube, the flange is conventionally pushed onto a ring provided at one end of the metal tube—without using further components—and welded to the metal tube from the inside. This procedure precludes welding from the outside in order to guarantee reliable connection of all layers of the tube end. Disadvantageously, in the MAG welding method (MAG=metal active gas; electric welding method with supplied welding wire which is melted-on) used therefor, welding spatters form which can deposit on the inner side of the metal tube, in particular of the agraff, since complete shielding of the inliner is thereby not possible. This is undesirable, since such material deposits have negative effects on the function of the metal tube, e.g. on its elastic properties, and can damage the engine and/or catalytic converter if they come off during operation. To prevent these disadvantages, the welding spatters must be removed in a later, costly processing step. For this reason, the above-described arrangement can be optionally fashioned with an additional intermediate tube disposed inside the metal tube between the connection flange and metal tube to prevent welding spatters. Towards this end, the flange and the metal tube are pushed onto the intermediate tube and welded thereto from the outside using MAG welding. This method is disadvantageous in that a second weld seam must be provided which increases production costs and the overall length of the arrangement is increased by approximately the length of the intermediate tube. It is therefore the underlying purpose of the present invention to produce a method and a device for connecting parts of an exhaust gas system, which eliminate the above-mentioned disadvantages and prevent welding splatter inside of the metal tube at minimum production cost without substantially increasing the overall length of the arrangement. SUMMARY OF THE INVENTION This object is achieved in accordance with the invention in that one end of a short connecting tube is positively inserted into one end of the metal tube and its other end is positively inserted into the system part to be connected with the metal tube, in particular a connection flange, wherein the system part is moved to the end of the metal tube facing the system part leaving an axial gap therebetween, and the system part, the connecting tube and the metal tube are connected to one another from the outside in one processing step. A short connecting tube is used instead of the intermediate tube and the system part can therefore be moved towards the end of the metal tube, leaving only a small axial gap. This permits connection of the system part, connecting tube and metal tube from the outside in one working step, with one single seam. External welding prevents spatters which adhere to the inside of the metal tube. The axial gap ensures that the generally thin wall of the bellows (i.e. the metal tube) is sealingly joined to the connecting tube in a controlled manner without requiring an excessive amount of heat. Such excessive heating could damage the welded portion of the tube and/or the weld seam to result in a leaky joint. Although the seam must, in principle, extend only partially along the circumference of the connecting tube in the region of the axial gap (weld adhesion, interrupted weld seam), in a preferred embodiment, it extends over the entire circumference of the connecting tube in the region of the gap thereby producing a completely gas-tight connection. One decisive standpoint of the invention consists in that all layers of the metal tube are connected. For embodiments with a weld seam connection, a particularly preferred embodiment of the invention provides that the weld seam has a specified fusion penetration in all bordering components. To adapt the system part and metal tube to different cross-sectional combinations, the connection tube can be tapered or stepped, i.e. the two ends can have different cross-sections, wherein the tapering can be effected in the direction of gas flow or opposite thereto. In a further embodiment, the connecting tube can have a plurality of steps wherein e.g. three or more diameters are provided sequentially, which each differ from the previous diameter. While the tube cross-sections can have any shape, such as elliptical or oval, and both ends can have different contours, in a preferred embodiment of the invention, at least one of the two facing cross-sections of metal tube and system part are circular. Both cross-sections can also be circular. If the metal tube and the system part have identical circular cross-sections, the connecting tube is preferably a hollow cylinder with such a cross-section. When the metal tube and the system part have different cross-sections, they are adapted in accordance with the invention in that one end of the connecting tube has a first outer diameter corresponding to the inner diameter of the system part and the other end of the connecting tube has a second outer diameter which corresponds to the inner diameter of the end of the metal tube facing it, wherein the transition between first and second outer diameters of the connecting tube to a central part of the connecting tube is continuous, and in particular, the central part has a truncated conical shape. In an extremely advantageous variant of the inventive method, in which a seal is provided between an end-side sealing surface of the system part and a counter piece opposite thereto, the seal to be inserted between the system part and the counter piece is centered wherein, in accordance with a preferred embodiment of the invention, the system part and its counter piece are preferably formed as flanges. The use of a seal, in particular of a flat seal is thereby particularly preferred in accordance with the invention. Centering is obtained in that the connecting tube extends in the direction of the tube axis, i.e. has an axial length such that it projects past the sealing surface of the system part by an amount M which corresponds approximately to the thickness of the seal to be used. In particular, this considerably simplifies mounting of a flanged joint and seal. With corresponding increased projecting length and suitable design of the connecting tube, the counter piece, in particular a counter flange can also be centered. The drawing illustrates concrete embodiments of the connection produced by the inventive method. The features contained herein are the subject matter of the dependent claims. BRIEF DESCRIPTION OF THE DRAWING FIG. 1a shows a sectional view of the inventive connection between a metal tube and a connection flange with a cylindrical connecting tube, without seam; FIG. 1b shows the same connection as FIG. 1a, however, with a weld seam; FIG. 2a shows the same connection as FIG. 1a, however, with a stepped or tapered connecting tube; FIG. 2b shows the same connection as FIG. 2a, however with a weld seam; FIG. 3a shows the same connection as FIG. 1a, however, with an extended connecting tube providing additional centering; and FIG. 3b shows the same connection as FIG. 3a, however, with a weld seam and a centered flat seal. DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a sectional view, in a plane perpendicular to tube axis A, of a connection between parts of an exhaust gas system produced by means of the inventive method. In the embodiment shown, the metal tube 1 comprises an agraff-inliner 2, a metal bellows 3 and an outer woven jacket 4 disposed coaxially, radially from the inside towards the outside. A short connecting tube 5, which, in the embodiment shown, is formed as hollow cylinder with circular cross-section is positively inserted with one end in a connecting flange 6 and with the other end in the metal tube 1 such that only a small axial gap 7 remains between the connecting flange 6 and the metal tube 1. An angle flange 8 is also disposed at the gap-side end of the metal tube 1. FIG. 1b shows a weld seam 9 which joins together the connecting tube 6, along its entire periphery and in the region of the axial gap 7, with the connecting flange 6 and all layers 2, 3, 4, 8 of the metal tube 1. Towards this end, the weld seam 9 has a certain fusion penetration in all of those neighboring components. In the embodiment of FIG. 1, the metal tube 1 and the connecting flange 6 have substantially identically sized (circular) cross-sections such that, in accordance with the inventive method, a hollow-cylindrical connecting tube 5 with identical cross-section is used. The (identical) inner diameters of the metal tube 1 and of the connecting flange 6 correspond to the outer diameter of the connecting tube 5. FIG. 2 is a sectional view as in FIG. 1 showing, however, a connection produced with the inventive method for an embodiment in which the metal tube 1 and the connecting flange 6 have different inner cross-sections or diameters. The connecting tube 5 is designed correspondingly such that one end has an outer diameter corresponding to the inner diameter of the metal tube 1 and its other end has an outer diameter which corresponds to the inner diameter of the connecting flange 6. The transition from one diameter to the other is continuous in a central region 10 of the connecting tube 5, which is located approximately in the region of the axial gap 7. In the concrete embodiment shown, the metal tube 1 and connecting flange 6 each have circular cross-sections and the connecting tube 5 has a truncated conical shape in the central region 10. The connecting flange 6 joins onto a counter piece 14. FIG. 3 shows a sectional view corresponding to FIGS. 1 and 2 of a connection produced with the inventive method comprising a connecting tube 5 which projects 11 past a sealing surface 12 of the connecting flange 6 on a side of the connecting flange 6 facing the metal tube 1. This projecting length 11 of the connecting tube 5 has a length M. FIG. 3b shows an additional flat annular seal 13 which is pushed onto the connecting tube 5 at its projecting region 11 and against the sealing surface 12 of the connecting flange thereby centering it via the connecting tube 5. The thickness of the flat seal 13 corresponds substantially to the length M of the projecting length 11. The seal 13 is disposed between the connecting flange 6 and counter piece 14. All three figures, in particular the respective partial figures b, clearly show that the inventive method produces a device for connecting parts of an exhaust gas system which requires only one seam 9 for secure connection of the relevant components 1, 5, 6 and which moreover ensures that during production, no material is deposited and accumulates within the metal tube 1 which would impair subsequent operation of the exhaust gas system. List of Reference Numerals 1 metal tube 2 agraff-inliner 3 bellows 4 woven jacket 5 connecting tube 6 system part (connecting flange) 7 axial gap 8 angle flange 9 (weld) seam 10 truncated central region 11 projection 12 sealing surface 13 (flat) seal 14 counter piece A tube axis M length of projection | <SOH> BACKGROUND OF THE INVENTION <EOH>The invention concerns a method and a device for connecting parts of an exhaust gas system using at least one metal tube formed from a bellows and optionally further parts which are disposed coaxially inside and/or outside of the bellows, and at least one further system part to be connected to the metal tube. In exhaust gas systems, in particular for motor vehicles, metal tubes are conventionally used having a woven jacket, a bellows disposed therein, an agraff-inliner, and optional further equipment. They are preferably used for tube-tube connections. A part of the exhaust gas system, e.g. a tube, is thereby inserted into the metal tube at the input and output sides and welded thereto. A special variant of this type of connection is a flange connection structure wherein at least one end of the metal tube is provided with a system part which is configured as a connecting flange and which can be connected to the exhaust gas system at an existing point of separation. To join the connection flange to the metal tube, the flange is conventionally pushed onto a ring provided at one end of the metal tube—without using further components—and welded to the metal tube from the inside. This procedure precludes welding from the outside in order to guarantee reliable connection of all layers of the tube end. Disadvantageously, in the MAG welding method (MAG=metal active gas; electric welding method with supplied welding wire which is melted-on) used therefor, welding spatters form which can deposit on the inner side of the metal tube, in particular of the agraff, since complete shielding of the inliner is thereby not possible. This is undesirable, since such material deposits have negative effects on the function of the metal tube, e.g. on its elastic properties, and can damage the engine and/or catalytic converter if they come off during operation. To prevent these disadvantages, the welding spatters must be removed in a later, costly processing step. For this reason, the above-described arrangement can be optionally fashioned with an additional intermediate tube disposed inside the metal tube between the connection flange and metal tube to prevent welding spatters. Towards this end, the flange and the metal tube are pushed onto the intermediate tube and welded thereto from the outside using MAG welding. This method is disadvantageous in that a second weld seam must be provided which increases production costs and the overall length of the arrangement is increased by approximately the length of the intermediate tube. It is therefore the underlying purpose of the present invention to produce a method and a device for connecting parts of an exhaust gas system, which eliminate the above-mentioned disadvantages and prevent welding splatter inside of the metal tube at minimum production cost without substantially increasing the overall length of the arrangement. | <SOH> SUMMARY OF THE INVENTION <EOH>This object is achieved in accordance with the invention in that one end of a short connecting tube is positively inserted into one end of the metal tube and its other end is positively inserted into the system part to be connected with the metal tube, in particular a connection flange, wherein the system part is moved to the end of the metal tube facing the system part leaving an axial gap therebetween, and the system part, the connecting tube and the metal tube are connected to one another from the outside in one processing step. A short connecting tube is used instead of the intermediate tube and the system part can therefore be moved towards the end of the metal tube, leaving only a small axial gap. This permits connection of the system part, connecting tube and metal tube from the outside in one working step, with one single seam. External welding prevents spatters which adhere to the inside of the metal tube. The axial gap ensures that the generally thin wall of the bellows (i.e. the metal tube) is sealingly joined to the connecting tube in a controlled manner without requiring an excessive amount of heat. Such excessive heating could damage the welded portion of the tube and/or the weld seam to result in a leaky joint. Although the seam must, in principle, extend only partially along the circumference of the connecting tube in the region of the axial gap (weld adhesion, interrupted weld seam), in a preferred embodiment, it extends over the entire circumference of the connecting tube in the region of the gap thereby producing a completely gas-tight connection. One decisive standpoint of the invention consists in that all layers of the metal tube are connected. For embodiments with a weld seam connection, a particularly preferred embodiment of the invention provides that the weld seam has a specified fusion penetration in all bordering components. To adapt the system part and metal tube to different cross-sectional combinations, the connection tube can be tapered or stepped, i.e. the two ends can have different cross-sections, wherein the tapering can be effected in the direction of gas flow or opposite thereto. In a further embodiment, the connecting tube can have a plurality of steps wherein e.g. three or more diameters are provided sequentially, which each differ from the previous diameter. While the tube cross-sections can have any shape, such as elliptical or oval, and both ends can have different contours, in a preferred embodiment of the invention, at least one of the two facing cross-sections of metal tube and system part are circular. Both cross-sections can also be circular. If the metal tube and the system part have identical circular cross-sections, the connecting tube is preferably a hollow cylinder with such a cross-section. When the metal tube and the system part have different cross-sections, they are adapted in accordance with the invention in that one end of the connecting tube has a first outer diameter corresponding to the inner diameter of the system part and the other end of the connecting tube has a second outer diameter which corresponds to the inner diameter of the end of the metal tube facing it, wherein the transition between first and second outer diameters of the connecting tube to a central part of the connecting tube is continuous, and in particular, the central part has a truncated conical shape. In an extremely advantageous variant of the inventive method, in which a seal is provided between an end-side sealing surface of the system part and a counter piece opposite thereto, the seal to be inserted between the system part and the counter piece is centered wherein, in accordance with a preferred embodiment of the invention, the system part and its counter piece are preferably formed as flanges. The use of a seal, in particular of a flat seal is thereby particularly preferred in accordance with the invention. Centering is obtained in that the connecting tube extends in the direction of the tube axis, i.e. has an axial length such that it projects past the sealing surface of the system part by an amount M which corresponds approximately to the thickness of the seal to be used. In particular, this considerably simplifies mounting of a flanged joint and seal. With corresponding increased projecting length and suitable design of the connecting tube, the counter piece, in particular a counter flange can also be centered. The drawing illustrates concrete embodiments of the connection produced by the inventive method. The features contained herein are the subject matter of the dependent claims. | 20050121 | 20100921 | 20050616 | 79940.0 | 0 | DUNWOODY, AARON M | DEVICE FOR CONNECTING PARTS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,258 | ACCEPTED | Duplicate data storing system, duplicate data storing method, and duplicate data storing program for storage device | Provided is a data storing system which holds only updated data by a snapshot action of a disk array subsystem. When there is generated a writing request to snapshot duplicate volumes as the duplicate data storing areas, unused pages for the requested amount is searched from a common logical-volume which is used in common as a real data storage area within the disk array subsystem, and address conversion of the page is performed. The result of the address conversion is held in a directory which is provided for each of the snapshot duplicate volumes. When making an access to the page thereinafter, the directory is always being referred to, and the address conversion is performed from the page of the snapshot duplicate volumes to the corresponding page of the common logical-volume. | 1. A duplicate data storing system of a storage device for storing an original data in a duplicate data storage area in accordance with update of the original data, the system comprising: a real data storage area for storing data to be written to a duplicate data storage area which is virtually built within the storage device; a data-storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area; and a data-storage area managing device for managing where, in real data storage area, data of the duplicate data storage area is stored. 2. The duplicate data storing system of a storage device according to claim 1, comprising: a held-data managing device for managing a use state of the real data storage area; and a real data storage area expanding device for increasing a storage capacity of the real data storage area. 3. The duplicate data storing system of a storage device according to claim 2, wherein the real data storage area expanding device is formed to increase the storage capacity of the real data storage area by expanding the real data storage area. 4. The duplicate data storing system of a storage device according to claim 2, wherein the real data storage area expanding device is formed to increase the storage capacity of the real data storage area by generating, in addition to the real data storage area, a new real data storage area within the storage device. 5. The duplicate data storing system of a storage device according to claim 1, wherein one or more of the real data storage areas are provided in the storage device and data in all the duplicate data storage areas within the storage device are stored in the one or more of the real data storage areas. 6. The duplicate data storing system of a storage device according to claim 1, wherein: the duplicate data storage areas within the storage device is divided into a plurality of groups; one or more of the real data storage areas are provided for each of the groups; and, further, a device having a list of the duplicate data storage areas and the real data storage areas belonging to the groups to is provided for each of the groups, so as to store the data in the duplicate data storage area within the group in the one or more of the real data storage area within the group. 7. The duplicate data storing system of a storage device according to claim 2, comprising an alarm generating device for generating an alarm which encourages an increase of the real data storage area when detecting that a used storage capacity of the real data storage area exceeds an alarm generating threshold value by setting an alarm generating threshold value for the real data storage area. 8. The duplicate data storing system of a storage device according to claim 2, wherein: an alarm generating threshold value is set for the real data storage area; an alarm for encouraging an increase of the real data storage area is generated when a used storage capacity of the real data storage area exceeds the alarm generating threshold value; and the real data storage area expanding device operates upon detecting the alarm. 9. The duplicate data storing system of a storage device according to claim 2, wherein the held-data managing device for managing the use state of the real data storage area includes a table for indicating presence of data by each memory unit through dividing the storage area of the real data storage area into memory units. 10. The duplicate data storing system of a storage device according to claim 2, wherein the held-data managing device for managing the use state of the real data storage area includes: a table for indicating presence of data by each memory unit through dividing the storage area of the real data storage area into memory units; a table for indicating presence of data by each memory unit group in which a plurality of the memory units are put together; and a table with a plurality of hierarchies in which a plurality of the memory unit groups are put together for indicating presence of data by each of the hierarchies. 11. The duplicate data storing system of a storage device according to claim 1, wherein the data storage area managing device maps the storage area of the real data storage area onto the duplicate data storage area side. 12. The duplicate data storing system of a storage device according to claim 11, wherein the data storage area managing device includes a table for mapping the storage area of the real data storage area onto the duplicate data storage area side and obtains an address conversion information for the real data storage area from an entry of the table. 13. The duplicate data storing system of a storage device according to claim 1, wherein the data storage area managing device maps the storage area of the duplicate data storage area onto the real data storage area side. 14. The duplicate data storing system of a storage device according to claim 13, wherein the data storage area managing device includes a table for mapping the storage area of the duplicate data storage area onto the real data storage area side and obtains an address conversion information for the real data storage area from an entry of the table. 15. The duplicate data storing system of a storage device according to claim 1, comprising a memory unit managing device for managing memory units set in the real data storage area, wherein the data storage area determining device comprises: a communication device for communicating with a corresponding storage area managing table which obtains a data section held by the duplicate data storage area; a communication device for communicating with an IO monitoring device which obtains an IO size of a read-command or write-command for the duplicate data storage area; and an unused area searching device for detecting an available memory unit in the real data storage area through searching the held-data managing device. 16. The duplicate data storing system of a storage device according to claim 15, wherein the unused area searching device is formed to detect an available storage area by selecting the real data storage area according to an IO size of a command for the duplicate data storage area. 17. The duplicate data storing system of a storage device according to claim 15, wherein the memory unit managing device is formed to manage the memory units set in each of the real data storage areas. 18. The duplicate data storing system of a storage device according to claim 15, wherein the memory unit managing device is formed to manage the memory units set in each area which is obtained by dividing the real data storage areas. 19. The duplicate data storing system of a storage device according to claim 1, comprising a data arranging device for rearranging data by each of the real data storage areas. 20. The duplicate data storing system of a storage device according to claim 19, wherein the data arranging device is formed to rearrange data when it is detected that data sections held in the real data storage areas are non-contiguous. 21. A duplicate data storing method of a storage device, comprising the steps of: determining a next storage area to be used in a contiguous arrangement within a real data storage area when duplicating data from a duplicate data storage area to the real data storage area which is for storing the data of the duplicate data storage area being virtually built within a storage device; and managing a correlation which indicates where, in the real data storage area, data of the duplicate data storage area is stored through storing the correlation within the storage device. 22. The duplicate data storing method of a storage device according to claim 21, wherein a storage capacity of the real data storage area is increased when detecting that a used storage capacity exceeds a threshold value by monitoring the used storage capacity of the real data storage area. 23. The duplicate data storing method of a storage device according to claim 21, wherein data are rearranged within the real data storage area by detecting that data sections held in the real data storage areas are non-contiguous. 24. A duplicate data storing program for storing data of a duplicate data storage area which is virtually built within a storage device in a real data storage area within the storage device, wherein: a microprocessor provided within the storage device is made to function as a data storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area so as to store data in the real data storage area; and also is made to function as a data storage area managing device for managing where, in the real data storage area, data of the duplicate data storage area is stored. 25. The duplicate data storing program according to claim 24, wherein, further, the microprocessor is made to function as a real data storage area expanding device for increasing a storage capacity of the real data storage area when detecting that a used storage capacity exceeds a threshold value by monitoring the used storage capacity of the real data storage area. 26. The duplicate data storing program according to claim 24, wherein, further, the microprocessor is made to function as a data arranging device for rearranging data within the real data storage area by detecting that data sections held in the real data storage area are non-contiguous. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to storing data into a storage device of a disk array subsystem and the like and, especially, to a duplicate data storing system, a duplicate data storing method, and a duplicate data storing program, which enable to improve an effective usage of the storage device capacity in a duplicate data storage area at the time of using snapshot technique while maintaining the disk-access performance. 2. Description of the Related Art When backing up the volume which constitutes a duplicate data storage area in a storage device of a disk array subsystem and the like, the volume as a backup target is duplicated inside the disk array subsystem and a backup server stores data read out from the duplicate data storage area to be the duplicate volume to a backup medium such as a tape drive. As the method for duplicating the volume, conventionally used is a method in which a complete duplicate of the backup target volume is formed. Naturally, in this case, it takes time which is proportional to the storage capacity of the volume of the backup target for completing the duplication of the volume. For increasing the use efficiency of the backup-target volume, Japanese Patent Unexamined Publication No. 2001-318833 discloses a technique in which a plurality of volumes are used around so as to select a duplicate volume appropriate for the capacity of the backup-target volume. This technique does not enable to shorten the time used for duplicating the volume. Also, it is necessary to reserve a plurality of the duplicate volumes for functioning as the duplicate data storage areas in advance to be used for backup, which causes such a shortcoming that the required storage capacity becomes redundant. Recently, in accordance with a remarkably increasing trend of reduction in backup window (system suspension time for backup processing), a technique such as snapshot or shadow copy has been put in use for duplicating the volume. The snapshot herein is a technique for maintaining the state of the volume as the snapshot-target volume at the time when being designated. For example, if a snapshot of the snapshot-target volume as shown in FIG. 1(a) in which data is stored is taken, first, a snapshot duplicate volume having a storage capacity equivalent to that of the snapshot-target volume is generated in a storage device in the manner as shown in FIG. 1(a). At a stage of writing data “EE” to a storage area of data “BB” of the snapshot-target volume, the data “BB” before update is stored in the same address of the snapshot duplicate volume in the manner as shown in FIG. 1(b), and the snapshot duplicate volume functions as a first-generation snapshot. At this time, if another snapshot of the snapshot-target volume is taken once again, a snapshot duplicate volume having the storage capacity equivalent to that of the snapshot-target volume is newly generated in the storage device in the manner as shown in FIG. 1(b), and the snapshot duplicate volume functions as a second-generation snapshot. Further, if it is desired to write data “FF” in a storage area of data “CC” of the snapshot-target volume, the data “CC” before update is stored in the same address of the snapshot duplicate volume which functions as a second-generation snapshot in the manner as shown in FIG. 1(c), while the content of the snapshot duplicate volume which functions as the first-generation snapshot is being held as shown in FIG. 1(b) or FIG. 1(c). Here, a series-type snapshot has been briefly described by referring to FIG. 1(a) to FIG. 1(c). In the case where a parallel-type snapshot is applied, when writing the data “FF” in the storage area of the data “CC” of the snapshot-target volume in the manner as shown in FIG. 1(c), the data “CC” is stored also in the first-generation snapshot in addition to the second-generation snapshot. In the volume duplicating method utilizing the snapshot technique, it may simply define the volume for holding only the update data to the backup-target volume right after the disk array subsystem receives a snapshot command. Thus, the backup-target volume can be seemingly duplicated at instant. Hereinafter, in the backup of the volume using the snapshot technique, the volume for storing an original data as the backup target is referred to as the snapshot-target volume, and the volume to be the duplicate data storage area for holding the update data of the backup-target volume is referred to as the snapshot duplicate volume, respectively. The use of the snapshot technique in the backup processing is only an example, and the snapshot technique is utilized in other various situations in the operation of the disk array subsystem. An example of a conventional data storing system for the snapshot duplicate volume using the snapshot technique will be specifically described by referring to FIG. 2 to FIG. 9. A conventional disk array subsystem 100 comprises: a device (logical-volume property managing table, 201 in FIG. 3) for judging by each logical-volume whether the logical-volume is the snapshot-target volume, the snapshot duplicate volume, or a volume of any other property; a device (logical-volume conversion table, 202 in FIG. 3) for address-converting a read-command or write-command which is issued by a host by designating the logical-volume into another logical-volume as the inner operation; and a device (held-data managing table, 203 in FIG. 3) for judging whether or not the snapshot duplicate volume holds the data required by the read-command or the write-command. The data held in the snapshot duplicate volume is managed in a size peculiar to the disk array subsystem 100, so that the read-command or the write-command from the host is divided into the peculiar management units described above by an IO monitoring device (400 in FIG. 7) to be processed by each management unit. FIG. 4, FIG. 5, and FIG. 6 illustrate the process of forming the duplicate of the volume and performing reading or writing from/to the volume in the disk array subsystem 100 employing the above-described data storing system. As the process for duplicating the volume, first, as shown in FIG. 4, the snapshot-target volume and the snapshot duplicate volume having at least the same storage capacity as that of the snapshot-target volume are formed within the disk array subsystem in a step 3a00. FIG. 2 shows the state of this process. In this example, two logical-volumes, that is, a logical-volume LV0 and a logical-volume LV1 are formed in the disk array subsystem 100. When the disk array subsystem receives a snapshot command having a parameter which indicates that the logical-volume LV0 is the snapshot-target volume and the logical-volume LV1 is the snapshot duplicate volume in a next step 3a01, the logical-volume property managing table 201, the logical-volume conversion table 202, and the held-data managing table 203 are initialized in a step 3a02. That is, the snapshot-target property is given to the logical-volume LV0 and the snapshot-duplicate property to the logical-volume LV1 in the logical-volume property managing table 201. In the logical-volume conversion table 202, LV1 is set as a logical-volume number after conversion corresponding to the logical-volume LV0, LV0 is set as a logical-volume number after conversion corresponding to the logical-volume LV1, and a value 0 indicating that the snapshot duplicate volume holds no data is set in the snapshot duplicate volume (that is, the logical-volume LV in this case) in the held-data managing table 203. The state of each table at this time is shown in FIG. 3. Next, described is a procedure of the processing performed at the time when the disk array subsystem 100 having the snapshot-target volume LV0 and the snapshot duplicate volume LV1 as described in the aforementioned procedure of volume duplicate receives the write-command and read-command. First, described is the processing process at the time of receiving the write-command (505 in FIG. 8). A microprocessor (simply referred to as CPU hereinafter) of the disk array subsystem 100 refers to the logical-volume property managing table 201 in a step 3b00 shown in FIG. 5 for judging whether the received command is a command for the snapshot-target volume or for the snapshot duplicate volume. The processing is completed without writing data when it is judged to be the write-command to the snapshot duplicate command in a step 3b01. This is the processing of the case where it is used to maintain the duplicate of the snapshot-target volume in the state of the point where the snapshot command is received in the snapshot duplicate volume, e.g., the processing for backup and the like. In other use data may be written onto the snapshot duplicate volume as requested by the write-command. In the meantime, when it is judged to be the write-command for the snapshot-target volume in a step 3b01, the CPU refers to the logical-volume conversion table 202 in a step 3b02 and specifies the snapshot duplicate volume as a pair of the snapshot-target volume. In a step 3b03, it is judged from the held-data managing table 203 whether there is data in the write-request address of the specified snapshot duplicate volume. When it is judged that the there is the data in the snapshot duplicate volume LV1, the data is written to the snapshot-target volume LV0 in a step 3b07 and the processing is completed. When it is judged that there is no data in the snapshot-target volume LV1, the data already stored in the write-request address of the snapshot-target volume LV0 is copied to the same address of the snapshot duplicate volume LV1 in a step 3b05. Then, a value 1 indicating that there is data in this area of the held-data managing table 203 is set in a step 3b06, and the data is written to the snapshot-target volume LV0 in a step 3b07. Thereby, the processing is completed. Next, described is a procedure of the processing performed at the time of receiving the read-command (506 in FIG. 8). The CPU refers to the logical-volume property managing table 201 in a step 3c00 shown in FIG. 6 for judging whether the received command is a command for the snapshot-target volume LV0 or a command for the snapshot duplicate volume LV1. When it is judged to be a command for the snapshot-target volume LV0 in a step 3c01, the data is read out from the snapshot-target volume LV0, and the processing is completed. In the meantime, when it is judged to be a command for the snapshot duplicate volume LV1 in a step 3c01, reference is made to the held-data managing table 203 in a step 3c02, and it is judged in a step 3c03 whether or not there is data in a read-out require address of the snapshot duplicate volume LV1. When it is judged that there is data in the snapshot duplicate volume LV1, the data is read out from the snapshot duplicate volume LV1 and the processing is completed. When it is judged that there is no data in the snapshot duplicate volume LV1, reference is made to the logical-volume conversion table 202 in a step 3c04 and recognizes the snapshot-target volume LV0 as a pair of the snapshot duplicate volume LV1. Then, the data is read out from the specified snapshot-target volume LV0 and the processing is completed. A first drawback of the above-described conventional art is that the use efficiency of the storage capacity is bad. The reason is that it is necessary in the data storing system of the snapshot duplicate volume in the conventional disk array subsystem to make a snapshot duplicate volume having at least the same storage capacity as that of the snapshot-target volume in spite that only the update data of the snapshot-target volume generated after receiving the snapshot command is copied to the snapshot duplicate volume. That is, in the above-described conventional art, data-copy from the snapshot-target volume to the snapshot duplicate volume has to be performed by the same address so that, logically, the snapshot duplicate volume is limited to be in the same configuration as that of the snapshot-target volume. A second drawback is that the data reading-out efficiency from the snapshot duplicate volume is bad. The reason is that, in the data storing system of the snapshot duplicate volume in the conventional disk array subsystem, the data-copy from the snapshot-target volume to the snapshot duplicate volume is symmetrically performed in between the volumes having logically the same configuration with the same address being the parameter. Accordingly, when the data-copy from the snapshot-target volume to the snapshot duplicate volume is generated in the scattered addresses, naturally, the data held in the snapshot duplicate volume becomes the scattered data. Thus, the effect of pre-fetching from a physical disk cannot be expected at all. An object of the present invention is to provide a duplicate data storing system, a duplicate data storing method, and a duplicate data storing program for enabling to form a duplicate volume which consumes a storage capacity proportional to an update data amount of a snapshot-target volume after receiving a snapshot command in a storage device such as a disk array subsystem. SUMMARY OF THE INVENTION The duplicate data storing system of the storage device according to the present invention achieved the above-described object through a feature which comprises a real data storage area for storing data to be written to a duplicate data storage area which is virtually built within the storage device; a data-storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area; and a data-storage area managing device for managing stored areas of data in the duplicate data storage area within the real data storage area. With the above-described configuration, the data to be written to the duplicate data storage area within the storage device at the time of updating the original data are all stored in the real data storage area. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate volume which requires the storage capacity equivalent to that of the volume for storing the original data. In other words, the duplicate data storage area of the present invention is only the area virtually built in the storage device and, substantially, it is formed by a data storage area managing device which manages where, in the real data storage areas, the data to be written to the duplicate data storage area is stored. The data storage area managing device is a kind of index table so that the storage capacity required for building the data storage area managing device is extremely small. The above-described configuration contains additionally a data-storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area. When the data is written to the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement for storing the data in order. Therefore, there is no vacant area to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. In addition to the above-described configuration, it is possible to provide a held-data managing device for managing a use state of the real data storage area and a real data storage area expanding device for increasing a storage capacity of the real data storage area. The use state of the real data storage area is managed by the held-data managing device and the storage capacity of the real data storage area can be increased by the real data storage area expanding device as necessary. Therefore, it is possible to surely store the data in the real data storage area even though the initial capacity of the real data storage area is set relatively small. More specifically, as the real data storage area expanding device, it is possible to employ a configuration in which the real data storage area itself is expanded for increasing the storage capacity. Such configuration is effective in the case where there are contiguous unused storage areas present in the real data storage area within the storage device. Further, the real data storage area expanding device may be so constituted to generate a new real data storage area within the storage device in addition to the real data storage area which has already been provided. In the case of employing such configuration, it is possible to increase the storage capacity of the real data storage area by additionally forming a new real data storage area in the unused storage area even when there is not a sufficient contiguous unused storage area present in the real data storage area, as long as there is a reasonable unused storage area present within the storage device. Here, one or more of the real data storage areas may be provided for storing data in all the duplicate data storage areas within the storage device to the one or more of the real data storage area. As described above, the data storage area managing device clearly specifies the correlation which indicates where the data to be written to the duplicate data storage area is stored in the real data storage area. Therefore, even there are a plurality of duplicate data storage areas and real data storage areas present within the storage device, there is no specific drawback to be caused in storing data and in specifying the storage areas and it enables to precisely correspond to the system with various volume structures. For example, by dividing the duplicate data storage area within the storage device into a plurality of groups; providing one or more of the real data storage areas for each of the groups; and, further, providing a device having a list of the duplicate data storage areas and the real data storage areas belonging to the groups to each of the groups, it is possible to store data of the duplicate data storage area within the group in the one or more of the real data storage areas within the group. In the case where such configuration is employed, the device for holding a list of the duplicate data storage areas and the real data storage areas functions as a part of the above-described data storage area managing device, which enables to precisely manage where the data to be written to the duplicate data storage area is written in the real data storage area in regards to the correlation between a plurality of the duplicate data storage areas and a plurality of the real data storage areas. It is possible that the required capacity of the real data storage area as the entire duplicate data storage areas which are put into a group can be estimated in advance. Thus, in the case where there is an upper limit in the storage capacity of a physical recording medium to which the real data storage area is provided, it is possible to effectively utilize the physical recording media such as hard disks and the like through optimizing a combination of the duplicate data storage areas as one group, or optimizing the number or the combination of the real data storage areas or the physical recording media corresponding to the group. It may comprise an alarm generating device for generating an alarm which encourages an increase of the real data storage area when a used storage capacity of the real data storage area exceeds an alarm generating threshold value by setting the alarm generating threshold value for the real data storage area. In the case where such configuration is employed, an alarm is generated before there is a shortage of the capacity generated in the real data storage area. Thus, by actuating the real data storage area expanding device at this point, a shortage of the capacity in the real data storage area can be prevented beforehand. More specifically, it is desirable to be in a configuration in which the real data storage area expanding device is actuated by an inside processing of the storage device by detecting the alarm from the alarm generating device. By employing such configuration, the data storage area expanding device operates when the used storage capacity of the real data storage area exceeds the alarm generating threshold value and the real data storage area is automatically increased. Therefore, it is possible to surely prevent the shortage of the capacity in the real data storage area. Further, at the stage of storing the data in the real data storage area, it is always guaranteed that there is a sufficient storage capacity in the real data storage area, so that it is possible to write the data in the real data storage area immediately. Thus, it enables to overcome shortcomings such as a decrease in the processing speed due to the waiting time generated in accordance with expansion or generation of the real data storage area and so on. Specifically, as for the above-described held-data managing device, the main part can be formed by a table which indicates the presence of data by each memory unit being obtained by dividing the storage area of the real data storage area. The held-data managing device may simply indicate only the presence of the data so that the required minimum memory unit may be 1 bit, for example. Thus, there is no shortcoming such as waste of the storage capacity and so on caused by providing the held-data managing device. Further, time required for referring to the held-data managing device is very short so that there is almost no bad effect such as delay in the inside processing being caused by referring to the table. The held-data managing device may be formed by: a table for indicating presence of data by each of the memory units which are obtained by dividing the storage area of the real data storage area; a table for indicating presence of data by a memory unit group in which a plurality of the memory units are put together; and a table with a plurality of hierarchies in which a plurality of the memory unit groups are put together for indicating presence of data of each group. There are various sizes of the data stored in the real data storage area, and for storing such data in the real data storage area, it may be necessary to divide the data under various conditions. Specifically, for example, there are concepts such as the minimum memory unit (page) determined according to the structure or format of the physical recording medium to which the real data storage area is provided and a memory unit group (segment) in which a plurality of memory units are put together. By utilizing the hierarchy table formed in accordance with the structure of such storage area as the held-data managing device, the time required for checking the presence of the data in the storage area of the real data storage area and, further, the time for required for reading/writing the data can be dramatically shortened. For example, in the case where contiguous data is stored over a plurality of pages, it is unnecessary to check the presence of data by each page but the presence of the data in the segment in which the pages are grouped into may be simply checked. Also, reading and writing of data can be achieved by a single access. The data storage area managing device may be formed by mapping the storage area of the real data storage area on the duplicate data storage area side. As described above, there is no physical limit in the relation between the real data storage area and the duplicate data storage area. However, when storing the data to the real data storage area, first, an access is made from the host side to the duplicate data storage area so that by mapping the data storing area managing device to be referred on the duplicate data storage area side, it is highly possible that the processing speed can be improved. Specifically, the data storage area managing device is formed to include a table for mapping the storage area of the real data storage area on the duplicate data storage area side and to obtain an address conversion information for the real data storage area from an entry of the table. The table is not for storing the real data but for storing only the address conversion information. Thus, like the above-described held-data managing device, shortcomings such as waste of the storage capacity and so on are not to be caused. Inversely, it is possible to form the data storage area managing device by mapping the storage area of the duplicate data storage area on the real data storage area side. In this case, the data storage area managing device is formed to include a table for mapping the storage area of the duplicate data storage area on the real data storage area side and to obtain address conversion information for the real data storage area from an entry of the table. Further, it is possible to employ a configuration comprising a memory unit managing device for managing memory units set in the real data storage area, wherein the data storage area determining device comprises: a communication device for communicating with a corresponding storage area managing table which obtains the data section held by a duplicate data storage area; a communication device for communicating with an IO monitoring device which obtains an IO size of a read-command or write-command for the duplicate data storage area; and an unused area searching device for detecting an available memory unit in a real data storage area through searching the held-data managing device. By employing such configuration, the data storage area determining device can obtain the IO size of the write-command from the IO monitoring device through the communication device, and also can check the memory unit which is set by the memory unit managing device. Therefore, based on the IO size as a unit of writing data and the memory unit of the storage area in the real data storage area, the available storage area in the real data storage area can be precisely detected by the unused area searching device for storing the data. Likewise, when reading out the data, the IO size of the read-command can be obtained from the IO monitoring device through the communication device. Accordingly, based on the IO size as a unit for reading the data or the memory unit, it is possible to precisely read out the data as a target of reading from the duplicate data storage area by referring to the corresponding storage area managing table. Here, it is desirable that the unused area searching device be so constituted that an available storage unit is detected by selecting the real data storage area according to an IO size of a command for the duplicate data storage area. In the case where a plurality of the real data storage areas with different memory units are used together, the available storage area is to be detected by selecting the real data storage area according to the IO size so that the storage capacity of the real data storage area can be most effectively utilized. It is possible to form the memory unit managing device so as to manage the memory units set in each of the real data storage areas. In the case where such configuration is employed, in the memory unit managing device, the memory unit used regularly in each of the real data storage areas is stored for the numbers of the real data storage areas. Accordingly, the data storage area determining device can store the data through precisely detecting the available storage area in the real data storage area by the unused area searching device, after selecting the real data storage area which fits the IO size based on the IO size as a unit of writing the data or the memory unit of each real data storage area. Therefore, it enables to achieve the effective use of the storage capacity of the real data storage area. Also, it is possible to form the memory unit managing device so as to manage the memory units set in each area which is obtained by dividing the real data storage area. In the case where such configuration is employed, in the memory unit managing device, several kinds of available memory units are to be stored in a single real data storage area. Accordingly, the data storage area determining device can store the data through precisely detecting the storage area having the memory unit corresponding to the IO size as a unit of writing data from the real data storage area by the unused area searching device. In this case, the size of the storage area in the real data storage area is not fixed but there area several kinds of sizes being mixed. Therefore, for storing the data, the storage area having the memory unit corresponding to the IO size is to be always selected so that it enables to achieve the effective use of the storage capacity of the real data storage area. Further, in addition to each of the above-described configurations, it is possible to provide a data arranging device for rearranging data by each of the real data storage areas. By employing such configuration, it is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. Further, it is desirable that the data arranging device be formed to rearrange data automatically when it is detected that the data sections held in the real data storage areas are non-contiguous. It is possible to shorten the time required for rearranging the data by rearranging the data before a strong fragmentation is generated. A duplicate data storing method of a storage device achieves the same above-described object by a configuration, comprising the steps of: determining a next storage area to be used in a contiguous arrangement within a real data storage area when duplicating data from a duplicate data storage area to the real data storage area which is for storing the data of the duplicate data storage area being virtually built within a storage device; and managing a correlation which indicates where, in the real data storage area, data of the duplicate data storage area is stored through storing it within the storage device. With the above-described configuration, the data to be written to the duplicate data storage area within the storage device at the time of updating the original data are all stored in the real data storage area. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate data storing method which requires a duplicate volume having the storage capacity equivalent to that of the volume for storing the original data. The real data is not stored in the duplicate data storage area so that it is necessary to manage the correlation between the virtual duplicate data storage area and the real data storage area which is for storing the real data by storing the corresponding relation within the storage device. However, the storage capacity required for building the data storage area managing device is extremely small so that there is no waste of the storage capacity being caused. Further, when the data is duplicated in the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement. Therefore, there is no vacant area to be generated carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. Further, a storage capacity of the real data storage area may be increased when a used storage capacity exceeds a threshold value by monitoring the used storage capacity of the real data storage area. It is possible to increase the storage capacity of the real data storage area as necessary by monitoring the use state of the real data storage area. Thus, it is possible to surely store the data in the real data storage area even through the initial capacity of the real data storage area is set relatively small. It may be configured to rearrange the data within the real data storage area by detecting that data held in the real data storage area is non-contiguous. It is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. A duplicate data storing program of the present invention is a duplicate data storing program for storing data of a duplicate data storage area which is virtually built within a storage device in a real data storage area within the storage device, which achieves the above-described same object by a configuration wherein: a microprocessor provided within the storage device is made to function as a data storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area so as to store data in the real data storage area; and also is made to function as a data storage area managing device for managing where, in the real data storage area, data of the duplicate data storage area is stored. The microprocessor provided within the storage device functions as the data storage area determining device and stores the data in order by determining the next storage area to be used in a contiguous arrangement when storing the data in the duplicate data storage area which is virtually built within the storage device to the real data storage area within the storage device. Thus, the vacant areas are not to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved. Thereby, the reading-out efficiency of data from the duplicate volume by pre-fetch can be improved. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate volume which requires the storage capacity equivalent to that of the volume for storing the original data. Further, the microprocessor provided within the storage device also functions as the data storage area managing device and manages where, in the real data storage area, the data to be written to the duplicate data storage area is stored. Since it is necessary for management, a kind of index table which forms the main part of the data storage area managing device is generated within the storage device. However, the storage capacity required for building the table is extremely small so that it is not a factor for disturbing the effective use of the storage capacity. Further, it may be so formed that the microprocessor within the storage device is made to function as a real data storage area expanding device by the duplicate data storing program. It is possible to increase the storage capacity of the real data storage area as necessary at the point where the used storage capacity exceeds the threshold value by monitoring the use state of the real data storage area. Thus, it is possible to surely store the data in the real data storage area even through the initial capacity of the real data storage area is set relatively small. Further, it is possible that the microprocessor within the storage device is made to function as a data arranging device by the duplicate data storing program. The data within the real data storage area is rearranged at the stage of detecting that the data section held in the data storage area is non-contiguous. Thus, it is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. In the present invention, only the data to be updated in the volume for storing the original data is to be stored in the real data storage area which substitutes the snapshot duplicate volume. Thus, compared to the conventional duplicate data storing system and the duplicate data storing method in which the data is stored by utilizing the duplicate volume having the storage capacity equivalent to the storage capacity of the volume to which the original data is stored, it is possible to dramatically reduce the storage capacity of the real data storage area which functions as a substantial duplicate volume. Further, when writing the data to the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement for storing the data in order. Therefore, there is no vacant area to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. Also, the data storage area managing device clearly specifies the correlation which indicates where the data to be written to the duplicate data storage area is stored in the real data storage area. Therefore, even there are a plurality of duplicate data storage areas and real data storage areas present within the storage device, there is no specific drawback to be caused in storing data and in specifying the storage area and it enables to precisely correspond to the system with various volume structures. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual figure for showing the functional principle of a snapshot; FIG. 2 is an illustration for showing a specific example of a conventional snapshot action (the state before writing is performed to a snapshot duplicate volume); FIG. 3 is a conceptual figure for showing the state of a corresponding storage area managing table right after receiving a snapshot command in a conventional case; FIG. 4 is a flowchart for showing a preparation performed before the conventional snapshot action; FIG. 5 is a flowchart for showing a write-command processing of the conventional snapshot action; FIG. 6 is a flowchart for showing a read-command processing of the conventional snapshot action; FIG. 7 is a functional block diagram for showing the schematic configuration of an IO monitoring device; FIG. 8 is an illustration for showing a specific example of a conventional snapshot action (the state after writing is performed to a snapshot duplicate volume); FIG. 9 is a conceptual figure for showing a corresponding storage area managing table after writing is performed to the snapshot duplicate volume in the conventional case; FIG. 10 is a functional block diagram for showing the schematic configuration of a disk array subsystem (First Embodiment); FIG. 11 is a functional block diagram for showing a specific example of the disk array subsystem of an embodiment to which the present invention is applied (First Embodiment); FIG. 12 is a functional block diagram for showing an address conversion device of the embodiment (First Embodiment); FIG. 13 is a functional block diagram for showing a data storage device of the embodiment (First Embodiment); FIG. 14 is a flowchart for showing the forming processing of a common logical-volume of the embodiment (First Embodiment); FIG. 15 is a flowchart for showing a preparation action of the embodiment (First Embodiment); FIG. 16 is a flowchart for showing the processing of a write-command of the embodiment (First Embodiment); FIG. 17 is a flowchart for showing the processing of a read-command of the embodiment (First Embodiment); FIG. 18 is a conceptual figure for showing the state of the disk array subsystem of the embodiment right after receiving the snapshot command (First Embodiment); FIG. 19 is a conceptual figure for showing the corresponding storage area managing table of the embodiment right after receiving the snapshot command (First Embodiment); FIG. 20 is a conceptual figure for showing the address conversion device of the embodiment right after receiving the snapshot command (First Embodiment); FIG. 21 is a conceptual figure for showing the state of the disk array subsystem of the embodiment after writing is performed to the snapshot duplicate volume (First Embodiment); FIG. 22 is a conceptual figure for showing the state of the corresponding storage area managing table of the embodiment after writing is performed to the snapshot duplicate volume (First Embodiment); FIG. 23 is a conceptual figure for showing the state of the address conversion device of the embodiment after writing is performed to the snapshot duplicate volume (First Embodiment); FIG. 24 is a conceptual figure for showing an address conversion device of another embodiment to which the present invention is applied (Second Embodiment); FIG. 25 is a functional block diagram for showing an IO monitoring device of the embodiment (Second Embodiment); FIG. 26 is a functional block diagram for showing a data storage area determining device of the embodiment (Second Embodiment); FIG. 27 is a conceptual figure for showing the state of the disk array subsystem of the embodiment after writing is performed to the snapshot duplicate volume (Second Embodiment); FIG. 28 is a conceptual figure for showing the state of the address conversion device of the embodiment after writing is performed to the snapshot duplicate volume (Second Embodiment); FIG. 29 is a functional block diagram for showing an address conversion device of still another embodiment to which the present invention is applied (Third Embodiment); FIG. 30 is a functional block diagram for showing a data storage area determining device of the embodiment (Third Embodiment); FIG. 31 is a conceptual figure for showing the state of the disk array subsystem of the embodiment after writing is performed to the snapshot duplicate volume (Third Embodiment); FIG. 32 is a conceptual figure for showing the state of the address conversion device of the embodiment after writing is performed to the snapshot duplicate volume (Third Embodiment); FIG. 33 is a conceptual figure for showing the state of the disk array subsystem at the time when there is an unused storage area generated in the common logical-volume (Third Embodiment); FIG. 34 is a conceptual figure for showing the state of a directory at the time when there is the unused storage area generated in the common logical-volume (Third Embodiment); FIG. 35 is a conceptual figure for showing the state of the disk array subsystem at the time when the data of the common logical-volume are relocated so as to fill the unused storage area generated in the common logical-volume (Third Embodiment); and FIG. 36 is a conceptual figure for showing the state of the directory at the time when the data of the common logical-volume are relocated so as to fill the unused storage area generated in the common logical-volume (Third Embodiment) DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment in which a duplicate data storing system, a duplicate data storing method, and a duplicate data storing program of the present invention are applied to a disk array subsystem as a storage device will be described in detail by referring to the accompanying drawings. FIG. 10 is a functional block diagram for showing a schematic configuration of a disk array subsystem 700 as hardware. The disk array subsystem 700 is for performing processing such as backup of data through allotting a plurality of magnetic disk devices 1100 for a managing terminal 1200, a host computer 1300 and the like as superior devices. The disk array subsystem 700 comprises an interface controller 1001 used for being connected to the superior devices and a RAID controller 1002 for connecting each of the magnetic disk devices 1100. As for the interface controller 1001 and the RAID controller 1002, input/output of data is controlled by a microprocessor 1004 (simply referred to as CPU hereinafter) which operates according to a control program stored in a control memory 1003. The CPU 1004 can be utilized as a various-function achieving device through rewriting the control program to be written onto the control memory 1003. Here, the CPU 1004 is utilized as: a data storage area determining device for determining a next storage area to be used when writing data to a real data storage area which is generated in the magnetic disk device 1100; a real data storage area expanding device for increasing a storage capacity of the real data storage area through expanding or adding the capacity; an alarm generating device for generating an alarm when the used storage capacity in the real data storage area exceeds an alarm generating threshold value; an unused area searching device for detecting an available memory unit in the real data storage area; and a data arranging device for rearranging the data by each of the real data storage areas, etc. Further, the interface controller 1001 comprises an IO monitoring device which obtains the IO sizes of a read-command and a write-command for the magnetic disk device 1100 from the managing terminal 1200 and the host computer 1300. FIG. 10 shows a case where six magnetic disk drives 1100 are connected. However, practically, each of the drives does not constitute logically independent volumes, such as the snapshot-target volume, the snapshot duplicate volume, or a common logical-volume or the like as a real data storage area, but it is possible to provide a seemingly single volume over a plurality of the magnetic disk drives 1100 and also possible to provide seemingly a plurality of volumes within a single magnetic disk drives 1100 by providing partitions in the single magnetic disk drives 1100. Here, this type of seeming volume is referred to as a logical-volume. First Embodiment FIG. 11 is a functional block diagram for simply illustrating a disk array subsystem 700 of a first embodiment from a functional point of view. As shown in FIG. 11, schematically, the disk array subsystem 700 comprises: snapshot-target volumes 701, 703 to which original data is stored, snapshot duplicate volumes 702, 704 functioning as duplicate data storage areas; a corresponding storage area managing table 708 for managing the states of the snapshot-target volumes 701, 703 and the snapshot duplicate volumes 702, 704; a common logical-volume 705 functioning as a real data storage area which is an actual storage area of the duplicate data; an IO monitoring device 707 for controlling each unit by monitoring input/output data to/from the disk array subsystem 700; and an address conversion device 706 for managing mapping of data from the snapshot duplicate volumes 702, 704 to the common logical-volume 705. There is no specific limit in the number of the snapshot-target volumes, the snapshot duplicate volumes, and the common logical-volumes. Here, there are two each of the snapshot-target volumes and the snapshot duplicate volumes and one common logical-volume provided as a mere example. The configuration of the corresponding storage area managing table 708 is substantially the same as that of the corresponding storage area managing table 200 shown in FIG. 3, which comprises a logical-volume property managing table 201, a logical-volume conversion table 202, and a held-data managing table 203. The corresponding storage area managing table 708 is enclosed in a control memory 1003. Like the conventional IO monitoring device 400 shown in FIG. 7, the IO monitoring device 707 of the interface controller 1001 contains a host-command fetching device 401, a host-command dividing device 402, and an initializing device 403 for initializing the corresponding storage area managing table 708. The address conversion device 706 is peculiar to this embodiment and, as shown in FIG. 12, comprises a table 801 (referred to as directory hereinafter) for indicating which of the block in the common logical-volume the data of a plurality of the snapshot duplicate volumes (for example, data of the snapshot duplicate volumes 702, 704) are in. It also comprises a common logical-volume held-data managing table 802 and a data storage area determining device 803. The address conversion device 706 and the data storage area determining device 803 are the functions achieved by the CPU 1004, and a directory 801 and the common logical-volume held-data managing table 802 are enclosed in the control memory 1003. As shown in FIG. 13, the data storage area determining device 803 contains an unused area searching device 901, a storage unit 902 for storing the size of the searched unused area, a storage unit 903 for storing an alarm generating threshold value, and an alarm generating device 904. The unused area searching device 901 and the alarm generating device 904 are achieved by using the CPU 1004 serving as a function achieving device, and the storage units 902, 903 are constituted by utilizing the storage area which is a part of the control memory 1003. Next, the overall operation of the embodiment will be described in detail by referring to flowcharts of FIG. 14 to FIG. 17, which illustrate outlines of the processing performed by the CPU 1004 provided to the disk array subsystem 700 of the embodiment. Before starting the snapshot action, as a preparation, the CPU 1004 of the disk array subsystem 700 forms the common logical-volume as an actual storage area of the data held by the snapshot duplicate volume according to the processing shown in FIG. 14. Specifically, first, the CPU 1004 forms the common logical-volume 705 in a step 10a00. The storage capacity of the common logical-volume 705 may be determined arbitrarily but it is desirable to be the storage capacity required at the moment by estimating the data amount to be duplicated. When the unused area of the common logical-volume 705 becomes less than a standard value by an increase in the duplicated data amount, the common logical-volume is expanded or a new common logical-volume is additionally generated by an automatic processing of the CPU 1004 which functions as the real data storage area expanding device 905. In order to simplify the management of the storage capacity of the common logical-volume, it is desirable to standardize the storage capacity of the common logical-volume to be added within the disk array subsystem 700. There is no data in each page of the common logical-volume 705 right after being formed by the processing of the step 10a00. Thus, by the initializing device 403 of the IO monitoring device 707, in the volume number section of the common logical-volume in the common logical-volume held-data managing table 802 functioning as the held-data managing device is initialized for indicating that there is no valid data (step 10a01). Next, the CPU 1004 of the disk array subsystem 700 performs the processing for starting the snapshot action according to the processing shown in FIG. 15. First, the CPU 1004 forms the snapshot duplicate volume having at least the same storage capacity as that of the snapshot-target volume in a step 10b00 shown in FIG. 15. The snapshot-target volume may be formed at this stage or the already-existing logical-volumes such as the logical-volume 701, 703 and the like may be designated as the snapshot-target volume. It is characteristic that, although the snapshot duplicate volume functioning as the duplicate data storage area has seemingly the same storage amount or more than that of the snapshot-target volume, the data of the snapshot are all stored in the common logical-volume 705. Thus, practically, the snapshot duplicate volume does not consume the storage capacity. In other words, the snapshot duplicate volume is only a volume virtually built within the disk array subsystem 700 and does not have a substantial storage capacity. Next, the disk array subsystem 700 receives a command from the host in a step 10b01. When it is judged by the IO monitoring device 707 that the command is a snapshot command, the corresponding storage area managing table 708 and the directory 801 as a part of the data storage area managing device are initialized by the initializing device 403 of the IO monitoring device 707. Then, in a step 10b02, the property of the snapshot-target volume or the snapshot duplicate volume is set in the volume number section of the logical-volume in the logical-volume property managing table 201, and the volume number of the other volume as a pair is respectively set in each volume number section of the logical-volume conversion table 202. Further, the section of the snapshot duplicate volume of the held-data managing table 203 is initialized to indicate that there is no valid data and the section of the snapshot duplicate volume of the directory 801 is initialized to indicate that the data of the common logical-volume is not allotted. It is possible to unify the held-data managing table 203 and the directory 801 as one since, while the data forms are different, the both show the position of the effective data of the snapshot duplicate volume. Hereinafter, the snapshot target volume is to hold the volume image (so-called a snapshot or a shadow copy) of the snapshot-target volume at the time of receiving the snapshot command. Next, the write-command processing will be described. When the disk array subsystem 700 receives a write-command and it is judged by the IO monitoring device 707 that it is a write-command for the volume being set for the snapshot, the write processing is executed according to the processing shown in FIG. 16. Specifically, first, the CPU 1004 of the disk array subsystem 700 refers to the logical-volume property managing table 201 in a step 10c00 for judging whether or not it is a command for the snapshot-target volume (step 10c01). When it is judged as the command for the snapshot-target volume, the CPU 1004 refers to the logical-volume conversion table 202 in a step 10c02 and specifies the snapshot duplicate volume which forms a pair with the snapshot-target volume. The processing performed when it is judged as a command for the snapshot duplicate volume is completed without writing to the volume, since writing to the snapshot duplicate volume is prohibited considering a normal use such as backup or the like. However, when writing to the snapshot duplicate volume is permitted, it proceeds to the following processing from a step 10c06. The data held by the snapshot duplicate volume is managed by a memory unit peculiar to the disk array subsystem 700. The above-described write-command is divided by the host-command dividing device 402 in a step 10c03 so that the received data can be processed by each of the specific managing unit. The processing thereafter is repeatedly executed for the numbers of the divided commands. Here, the managing unit peculiar to each disk array subsystem 700 is referred to as a page. The held-data managing table 203 of the corresponding storage area managing table 708, the directory 801 of the address conversion device 706, and the common logical-volume held-data managing table 802 of the address conversion device 706 manage the presence of the data and the allotting state of the data with respect to the common logical-volume by each page. In other words, the common logical-volume held-data managing table 802 which functions as a held-data managing device is a table which indicates the presence of the data by each page as a memory unit. Next, the CPU 1004 refers to the held-data managing table 203 in a step 10c04 and judges whether or not there is set a value indicating the presence of data held in a position of the snapshot duplicate volume which corresponds to a position of the page on the snapshot-target volume where the data is to be written at the moment (step 10c05). When it is judged that there is data held in the snapshot duplicate volume, that is, backup of the page has been already achieved, the data is written to the snapshot-target volume and the processing is completed. In the meantime, when it is judged that there is no data held in the snapshot duplicate volume, the unused area searching device 901 searches the common logical-volume held-data managing table 802 and refers it with the size of the search-target unused area set in the storage unit 902. Then, the storage area of the data stored in the corresponding position of writing data in the snapshot-target volume at the moment is searched. The next storage area to be used in the common logical-volume 705 is so selected to be in a contiguous arrangement from the front address and the data is stored in that storage area (step 10c06). Here, it is possible to shorten the searching time by improving the searching efficiency through forming the common logical-volume held-data managing table 802 with a hierarchy structure. For example, in addition to indicating the presence of the data by each page as a memory unit, it is possible to indicate the presence of data by each memory-unit group in which a plurality of memory units are put together and, further, to provide a table indicating the presence of data of a plurality of memory-unit groups collectively. Thereafter, the CPU 1004 copies the page in the corresponding position of writing data in the snapshot-target volume described above to the data storage position on the common logical-volume 705 which is determined in the step 10c06. The value for indicating that the page is in use is set in the common logical-volume held-data managing table 802 functioning as the held-data managing device, and the volume number and the page number of the common logical-volume to which the data is stored is set in the page of the snapshot duplicate volume of the directory 801 which functions as a part of the data storage area managing device. Further, the value for indicating that there is data being held is set in the page of the snapshot duplicate volume in the held-data managing table 203 (step 10c07, step 10c08, step 10c09). In the embodiment, the directory 801 is built by a configuration in which the common logical-volume number and the page address are mapped in the storage area on the snapshot duplicate volume side. Inversely, it may be in a configuration in which the directory 801 is formed by mapping the snapshot duplicate volume number and the page address in the storage area on the common logical-volume side. Next, the CPU 1004 judges whether or not the unused area of the common logical-volume becomes less than the alarm generating threshold value set in the storage unit 903 by the use of the common logical-volume of this time. When it becomes less, the CPU 1004 functioning as the alarm generating device 904 generates an alarm for encouraging the expansion or generation of the common logical-volume (step 10c10, step 10c11). The processing associated with the expansion or generation of the common logical-volume may be started by a command from the host-command or may be started automatically as the inside processing of the disk array subsystem 700 at the time of detecting the alarm generation. In the embodiment, the overall storage area of the common logical-volume can be increased by selecting either expansion or generation of the volume. When the expansion of the volume is selected, the CPU 1004 functioning as the real data storage area expanding device 905 redefines the storage area contiguous to the target common logical-volume as the storage area of the common logical-volume. When the generation of the volume is selected, the CPU 1004 functioning as the real data storage area expanding device 905 detects the vacant area with the size of the set value or larger and sets the vacant area as the storage area which newly functions as the common logical-volume. In this manner as described, the used state of the common logical-volume as the real data storage area can be managed by the common logical-volume held-data managing table 802 and the substantial storage capacity of the common logical-volume can be increased as necessary by the real data storage area expanding device 905. Thus, it is possible to surely store the data in the common logical-volume even though the initial capacity of the common logical-volume is set relatively small. At last, the CPU 1004 writes the data inputted from the host to the snapshot-target volume and the processing is completed (step 10c12). As described above, when the command is being divided, the above-described processing is repeatedly executed and the processing is completed at the point where writing of the last divided data is completed. Next, the read-command processing will be described. As for the read-command processing, when the disk array subsystem 700 receives a read-command and the IO monitoring device 707 judges that it is a read-command for the volume being set as the snapshot, it is executed according to the processing shown in FIG. 8. In a step 10d00, first, the CPU 1004 refers to the logical-volume property managing table 201, and judges whether or not it is a read-command for the snapshot-target volume (step 10d01). When it is the command for the snapshot-target volume, the data is read out from the snapshot-target volume and the processing is completed (step 10d07). In the meantime, when it is judged that the command is for the snapshot duplicate volume (step 10d01), the command is divided into a page unit as in the case of the write-command (step 10d02), and the processing thereafter is repeatedly executed for the numbers of the divided commands. In this case, first, the CPU 1004 refers to the held-data managing table 203 in a step 10d03, and judges whether or not the value indicating that there is data being held is set in the page position on the snapshot duplicate volume from which the data is to be read out (step 10d04). When it is judged that there is the data held in the snapshot duplicate volume, the data is read out from the volume number and the page number of the common logical-volume set in the page of the snapshot duplicate volume in the directory 801 (step 10d06, step 10d07). Further, when it is judged that there is no data held in the snapshot duplicate volume, the CPU 1004 refers to the logical-volume conversion table 202 and specifies the snapshot-target volume corresponding to the snapshot duplicate volume (step 10d05). Then, the data is read out from the corresponding page on the snapshot-target volume (step 10d07) As described above, the snapshot duplicate volume functioning as the duplicate data storage area is not substantial and all the data of the snapshot duplicate volume are actually stored in the common logical-volume serving as the real data storage area. Therefore, even when duplicating a large number of volumes, it only requires the storage capacity that is a difference between the snapshot-target volume and the snapshot duplicate volume to be consumed, i.e. the storage capacity corresponding to the update data amount for the snapshot-target volume after receiving the snapshot command. Next, the operation of the embodiment will be described by referring to a specific example. Here, shown as an example in FIG. 18, FIG. 19, FIG. 20 is a state right after receiving a snapshot command in a disk array subsystem 700 which comprises a first snapshot-target volume 701, a first snapshot duplicate volume 702 having the same storage capacity as that of the snapshot-target volume 701, a second snapshot-target volume 703, a second snapshot duplicate volume 704 having the same storage capacity as that of the snapshot-target volume 703, and a common logical-volume 705 which actually stores the data of the snapshot duplicate volumes 702, 704. For starting the snapshot action, first, the CPU 1004 forms the common logical-volume 705 as the real data storage area, and then clears the value in the section of the volume number LV0 allotted by corresponding to the common logical-volume 705 to “0” for indicating that there is no data in the common logical-volume held-data managing table (802 in FIG. 20). In order to clearly illustrate the feature of the embodiment, the value “1” is set for the page 1 on assumption that it has been already used. Next, the CPU 1004 starts the snapshot action and forms the first snapshot duplicate volume 702 having the same capacity as that of the first snapshot-target volume 701 and the second snapshot duplicate volume 704 having the same capacity as that of the second snapshot-target volume 703. The numbers of these logical-volumes are defined to be LV0, LV1, LV2, LV3, respectively. Upon receiving a snapshot executing command for setting the snapshot duplicate volume LV1 as the snapshot of the snapshot-target volume LV0 and also setting the snapshot duplicate volume LV3 as the snapshot of the snapshot-target volume LV2, the CPU 1004 sets the respective property to the sections of each volume number in the logical-volume property managing table (201 in FIG. 19), sets the volume number of the other volume as a pair of the snapshot action in the sections of each volume number in the logical-volume conversion table (202 in FIG. 19), clears the sections of the volume number LV1 and the volume number LV3 in the held-data managing table (203 in FIG. 19) by setting the value “0” indicating that it is unused, and sets “null” in the sections of the volume number LV1 and the volume number LV3 in the directory (801 in FIG. 20) for indicating that there is no common logical-volume being allotted. These are the preparations performed before the snapshot action. Next, the process of storing the data to the snapshot duplicate volume will be described. The write-command and the read-command for the snapshot duplicate volume are divided into each memory unit called as a page by the host-command dividing device (402 in FIG. 34) in the same manner as that of the conventional case. The page size is desirable to be about some tens to hundreds KB. Here, it is supposed to be 32 KB. Provided that a write-command (1409 in FIG. 21) for the snapshot-target volume LV0 is received at this moment, the CPU 1004 recognizes it as a write-command for the first snapshot-target volume LV0 by referring to the volume number LV0 in the logical-volume property managing table (201 in FIG. 19). Next, the address conversion device 706 recognizes that the snapshot duplicate volume of the snapshot-target volume LV0 is the snapshot duplicate volume LV1 by referring to the logical-volume conversion table (202 in FIG. 19) and converts the target of the command to the snapshot duplicate volume LV1. Next, the CPU 1004 refers to the held-data managing table (203 in FIG. 19) and judges whether or not data is written before in the respective page of the snapshot duplicate volume LV1. If data has been already written, “AF” which corresponds to the first 32 KB of the data of the write-command (1409 in FIG. 21) is written to the page 0 of the snapshot-target volume LV0, and “BG” which indicates the remaining 32 KB is written to the next page 1. Thereby, the processing corresponding to the command being divided into two is completed. In the meantime, when there is no data written in the respective page of the snapshot duplicate volume LV1, the target of the command is converted to the data storing storage area determined by the data storage area determining device (803 in FIG. 20). In this case, the unused area searching device (901 on FIG. 13) searches the contiguous vacant areas in the size of the searched unused area (902 in FIG. 13) from the common logical-volume LV0. It may be the vacant area searched in the first place with the size of the unused area (902 in FIG. 13) or larger, or may be the vacant area determined by other algorithm. In this example, the page 0 of the snapshot duplicate volume LV1 is converted to the page 0 as the first vacant page of the common logical-volume LV0, and the page 1 of the snapshot duplicate volume LV1 is converted to the page 2 as the next vacant page of the common logical-volume LV0. The value “AA” of the page 0 of the snapshot-target volume LV0 and the value “BB” of the page 1 of the snapshot-target volume LV0 are copied to the respective pages. Then, “the volume number LV0 of the common logical-volume and page 0” is set in the page 0 in the section of the volume number LV in the directory (801 in FIG. 20). Also, “the volume number LV0 of the common logical-volume and page 2” is set in the page 1 of the same, while the value “1” is set in the section of the volume number LV0 of the common logical-volume in the position between the page 0 and page 2 in the common logical-volume held-data managing table (802 in FIG. 20) for indicating that it is being used. Then, the value “1” for indicating that there is data being held is set in the page 0 and page 1 in the same manner performed in the section of the volume number LV1 in the held-data managing table (203 in FIG. 19). Subsequently, the CPU 1004 judges whether or not the vacant area of the common logical-volume LV0 has exceeded the alarm generating threshold value through the writing data in the page 0 and the page 2 of the common logical-volume LV0 by the unused area searching device (901 in FIG. 13). When it is judged that it has exceeded the threshold value, the alarm generating device (904 in FIG. 13) generates an alarm for encouraging an increase in the common logical-volume. At last, the data “AF” is written to the page 0 of the snapshot-target volume LV0 and the data “BG” is written to the page 1. Thereby, the processing corresponding to the command being divided into two is completed. Next, provided that a write-command (1410 in FIG. 21) for the snapshot-target volume LV2 is received, the data of the page 1 of the snapshot-target volume LV2 is copied to the page 3 as a first vacant page of the common logical-volume LV0 after going through the same processing as the write-command to the snapshot-target volume LV0 described above. Then, the data “bk” is written to the page 1 of the snapshot-target volume LV2. The states after executing the above-described two write-commands (1409 and 1410 in FIG. 21) are shown in FIG. 21, FIG. 22, and FIG. 23. As described above, all the data to be stored in a plurality of the snapshot duplicate volumes LV1, LV3—are collectively managed by the common logical-volume LV0. Second Embodiment Next, the memory unit managing device for managing the memory unit set in the common logical-volume will be described by referring to an embodiment in which it is provided to the address conversion device 706. As shown in FIG. 24, the address conversion device 706 of the embodiment comprises a directory 801, a common logical-volume held-data managing table 802, a data storage area determining device 803, and a common logical-volume chunk managing table 1703 which functions as a memory unit managing device. The common logical-volume chunk managing table 1703 is enclosed in a control memory 1003. Further, as shown in FIG. 25, the IO monitoring device 707 comprises a host-command fetching device 401, an IO size informing device 1802, an initializing device 403 of corresponding storage area managing table, and a host-command dividing device 403. Then, as shown in FIG. 26, the data storage area determining device 803 comprises an unused area searching device 901, a searched unused area size determining device 1902, and alarm generating device 904, a storage unit 903 for storing the alarm generating threshold value, and a communication device 1905 for communicating with the IO monitor device 707, and a communication device 1906 for communicating with the corresponding storage area managing table 708. Except that it comprises the common logical-volume chunk managing table 1703, the IO size informing device 1802, and the communication devices 1905, 1906, it is the same as the above-described disk array subsystem 700 of the first embodiment in regards to the substantial configuration. In the embodiment, writing of the data to the snapshot duplicate volume is not performed by the memory unit peculiar to the disk array subsystem 700 but performed by the size which is determined kinetically according to the IO size designated by the write-command. This embodiment is different from the above-described first embodiment in this respect. Here, the writing size which is kinetically determined is referred to as a chunk. Further, the common logical-volume is divided into managing units referred to as segments and the chunk size to be stored in the segment is set in each segment, so that there is no writing by different chunk sizes to be performed in a single segment. In this case, when a write-command from the host is received, the IO monitoring device 707 informs the IO size of the command to the data storage area determining device 803 through the IO size informing device (1802 in FIG. 25) and the unused area size determining device (1902 in FIG. 25) determines the chunk size from the informed IO size and the memory unit (page size) peculiar to the disk array subsystem 700. Further, the unused area searching device (1901 in FIG. 25) refers the chunk size to the common logical-volume chunk managing table (1703 in FIG. 24) for determining the corresponding segment, and searches the vacant area of the common logical-volume for storing the data. Further, when the corresponding segment is not found, the CPU 1004 functioning as the data storage area managing device sets the above-described chunk size (determined chunk size) anew for the segment in which the chunk size is unset, and the data is stored in the segment. The processing hereinafter is the same as the case of the above-described first embodiment. In this embodiment, the common logical-volume is divided into units called as the segments, the chunk size is set in each of the segments, and the data is written to the segment which corresponds to the IO size of the write-command. Thus, the write data designated by a single command is not to be dispersed on the common logical-volume over a plurality of the segments, so that deterioration in the access performance can be surely prevented as long as there is no careless deleting of data being performed. Next, the operation of the embodiment will be described by referring to a specific example. The preparation performed before the snapshot is the same as the case of the above-described first embodiment. Thus, only the process of storing data to the snapshot duplicate volume will be described herein. In the embodiment, the writing size to the snapshot duplicate volume is determined kinetically according to the IO size of the write-command. In order to simplify the chunk size management, it is desirable to set the chunk size to be an integral multiple of the managing unit (page) peculiar to the disk array subsystem 700. Provided that a write-command (2009 in FIG. 27) for the first snapshot-target volume LV0 is received at this moment, the IO size is informed to the data storage area determining device (803 in FIG. 26) from the IO monitoring device (707 in FIG. 25), and it is determined by the unused area size determining device (1902 in FIG. 26) that the chunk size of the data “AF”, “BG” is two pages (64 KB). However, the chunk size is adjusted to be one page (32 KB) in the case where it is determined that there has been data already written in the page 0 of the snapshot duplicate volume LV1 after judging it through: recognizing that the command is the write-command for the snapshot-target volume LV0 by referring to the volume number LV0 in the logical-volume property managing table (201 in FIG. 19), converting the target of the command to the first snapshot duplicate volume LV1 by referring to the logical-volume conversion table (202 in FIG. 19), and judging whether or not writing has been performed before in the respective page of the snapshot duplicate volume LV1 by referring to the held-data managing table (203 in FIG. 19). Next, the unused area searching device (901 in FIG. 26) determines or selects the segment which corresponds to the chunk size by referring to the common logical-volume chunk managing table (1703 in FIG. 28). The segment size is desirable to be in the size of about some MB to some GB in consideration of the size of the managing table and the search efficiency. In the initial state, the chunk sizes are unset in all the segments, so that the CPU 1004 functioning as the data storage area managing device sets the segment 0 as the first segment of the common logical-volume LV0 to be the segment to which the data with the chunk size of 64 KB is written. The operation hereinafter is the same as the case of the above-described first embodiment. Next, provided that a write-command (2010 in FIG. 27) for the second snapshot-target volume LV2 is received, the chunk size of “bk” is determined as one page after going through the same processing as that of the write-command for the first snapshot-target volume LV0, and the unused segment 1 in the common logical-volume chunk managing table (1703 in FIG. 28) is set to be 32 KB. Then, after copying the data of the page 1 of the second snapshot-target volume LV2 to the segment 1 of the common logical-volume LV0, the data received by the above-described write-command is written to the page 1 of the second snapshot-target volume LV2. The state after executing the above-described two write-commands (2009 in FIGS. 27 and 2010 in FIG. 27) is shown in FIG. 27 and FIG. 28. As described, the CPU 1004 functioning as the data storage area managing device divides the common logical-volume into units called the segments according to the IO size required by the host and sets the chunk size by each segment. Thus, it is possible to store the data to the corresponding segment without dividing the IO size requested by the host. In this case, through indicating the presence of data by each memory unit group in which a plurality of the memory units are put together (that is, by each segment) in the common logical-volume held-data managing table 802 in addition to indicating the presence of data by each page as the memory unit, it enables to further improve the search efficiency, access speed and the like. For example, it is possible to utilize the address of the page positioned in the first segment as the address representing the segments. Third Embodiment Next, described is an embodiment in which a data arranging device for rearranging the data is provided in each real data storage area. As shown in FIG. 29, the address conversion device 706 of the embodiment comprises a directory 801, a common logical-volume held-data managing table 802, a data storage area determining device 803, and a data arranging device 2204. In the embodiment, writing to the snapshot duplicate volume is not performed by each memory unit peculiar to the disk array subsystem 700 but is performed by each chunk unit which is kinetically determined according to the IO size designated by the write-command. Upon receiving the write-command from the host, the IO monitoring device 707 informs the IO size of the command to the data storage area determining device 803 through the IO size informing device (1802 in FIG. 25). The unused area size determining device (1902 in FIG. 30) determines the chunk size from the informed IO size and the memory unit peculiar to the disk array subsystem 700, and the unused area searching device (901 in FIG. 30) refers the chunk size to the common logical-volume held-data managing table (802 in FIG. 29) and determines the common logical-volume and the page for storing the data. When the unused areas of the common logical-volume are to be dispersed as a result of repeating the writing of data to the snapshot duplicate volume and deleting of the snapshot duplicate volume, the data arranging device (2204 in FIG. 29) rearranges the data within the common logical-volume so that the unused areas are positioned in the contiguous page addresses. The processing hereinafter is the same as the case of the first embodiment. In the embodiment, it is so configured that the data is stored in the common logical-volume by a chunk unit which is kinetically determined by each command. Thus, the write-data designated by a single command are not to be dispersed on the common logical-volume so that deterioration in the access performance can be prevented. Further, it is so configured that the data is rearranged so that the unused areas are positioned in the contiguous page addresses in the case where the unused areas are dispersed on the common logical-volume due to deletion of the snapshot duplicate volume and the like. Thus, it is unnecessary to prepare the segment for each chunk size and it enables to omit the common logical-volume chunk managing table. Further, it is possible to improve the use efficiency of the storage capacity. Next, the operation of the embodiment will be described by referring to a specific example. The preparation performed before the snapshot is the same as the case of the above-described first embodiment. Thus, only the process of storing data to the snapshot duplicate volume will be described herein. In the embodiment, the writing size to the snapshot duplicate volume is determined kinetically according to the IO size of the write-command. In order to simplify the chunk size management, it is desirable to set the chunk size to be an integral multiple of the managing unit (page) peculiar to the disk array subsystem 700. Provided that a write-command (2409 in FIG. 31) for the first snapshot-target volume LV0 is received at this moment, the IO size is informed to the data storage area determining device (803 in FIG. 30) from the IO monitoring device (707 in FIG. 21), and it is determined by the unused area size determining device (1902 in FIG. 30) that the chunk size of the data “AF”, “BG” is two pages (64 KB). However, the chunk size is adjusted to be one page (32 KB) in the case where it is determined that there has been data already written in the page 0 of the snapshot duplicate volume LV1 after judging it through: recognizing that the command is the write-command for the snapshot-target volume LV0 by referring to the volume number LV0 in the logical-volume property managing table (201 in FIG. 19), converting the target of the command to the first snapshot duplicate volume LV1 by referring to the logical-volume conversion table (202 in FIG. 19), and judging whether or not writing has been performed before in the respective page of the snapshot duplicate volume LV1 by referring to the held-data managing table (203 in FIG. 19). Next, the unused area searching device (901 in FIG. 30) determines the unused page with the chunk size or larger, which is found first when the common logical-volume is searched from the front, or the unused page which best fits to the chunk size, or the unused page determined by other algorithm as the page address of common logical-volume to be used next. The operation hereinafter is the same as the case of the above-described first embodiment, in which the data “AF” is written to the page 0 of the snapshot-target volume LV0 and the data “BG” is written to the page 1 after copying the data of the page 0 and the page 1 of the snapshot-target volume LV0 to the page 2 and page 3 having the contiguous vacant area with 64 KB or larger in the common logical-volume LV0. Next, provided that a write-command (2410 in FIG. 31) for the second snapshot-target volume LV2 is received, the chunk size of “bk” is determined as one page (32 KB) after going through the same processing as that of the write-command for the first snapshot-target volume LV0. After the unused area searching device (901 in FIG. 30) copies the data of the page 1 of the snapshot-target volume LV2 to the vacant area of 32 KB which is searched first from the common logical-volume LV0 (that is, the page 0 of the common logical-volume LV0), the data “bk” is written to the page 1 of the snapshot-target volume LV2. Next, the data arranging procedure 2204 will be described. When forming the snapshot duplicate volume, writing to the snapshot duplicate volume, and deletion of the snapshot duplicate volume are repeatedly executed, unused pages in various sizes are to be dispersedly positioned on the common logical-volume LV0, since the writing size to the snapshot duplicate volume is kinetically determined according to the IO size of the write-command. Thus, it is possible that writing to the snapshot duplicate volume cannot be achieved in some of the cases since all of the chunk sizes are unsatisfied for the chunk size even though there are a large amount of unused pages all together. The data arranging device (2204 in FIG. 32) periodically searches the common logical-volume held-data managing table (802 in FIG. 32) and relocates the pages so that the unused pages are not to be dispersed in the common logical-volume. After relocating the page, 0 is set to the page before the relocation in the common logical-volume held-data managing table (802 in FIG. 32) and 1 is set in the page after the relocation. The respective section of the directory (801 in FIG. 32) is rewritten to the page address which indicates the data on the common logical-volume after the relocation. Now, an example of the processing operation of the data arranging device 2204 will be described specifically by referring to FIG. 33 to FIG. 36. FIG. 33 is a conceptual figure for showing the state of the disk array subsystem before and after deleting the snapshot duplicate volume 704 which is the snapshot of the snapshot-target volume 703. In the embodiment, as has been described, the data to be stored in the snapshot duplicate volume 704 functioning as the duplicate data storage area is stored in the common logical-volume 705 as the real data storage area at last. Thus, deletion of the snapshot duplicate volume 704 means deletion of the corresponding data in the common logical-volume 705 in which the data of the volume 704 is actually stored. In this case, as shown in the directory 801 of FIG. 34, the data to be stored in the page 1 of the snapshot duplicate volume 704 having the volume number LV3 is stored in the page 1 of the common logical-volume 705 having the volume number LV0. Thus, when there is a deletion command for the snapshot duplicate volume 704, the CPU 1004 refers to the directory 801 of FIG. 34 and deletes the data “bb” of the page 1 of the common logical-volume 705, while setting the value 0, indicating that it is unused, in the section of the page 1 of the volume number LV0 which corresponds to the common logical-volume 705 in the common logical-volume held-data managing table 802 of FIG. 34. By deleting the data “bb” of the page 1 of the common logical-volume 705 as described above, the page 1 of the common logical-volume 705 becomes an unused page. When the data arranging device 2204 is started, the data after the page 2 of the snapshot duplicate volume 704 is shifted by one page to be relocated in the page on the front side. For example, “BB” which is the data of the page 2 of the common logical-volume 705 in FIG. 33 is relocated to the page 1 of the common logical-volume 705 in the manner as shown in FIG. 35. In accordance with the execution of the relocating processing, the value 1 indicating that it is used is set anew in the section of the page 1 of the volume number LV0 corresponding to the common logical-volume 705 in the common logical-volume held-data managing table 802 shown in FIG. 36, and also the storage area corresponding to the data which is relocated in the common logical-volume 705 is updated and rewritten as shown in the directory 801 of FIG. 36. In this case, the data of the page 2 of the common logical-volume 705 shown in FIG. 33 (that is, the data of the page 1 of the snapshot duplicate volume 702 which corresponds to the volume number LV1 in the directory 801 shown in FIG. 34) is shifted from the front by one page within the common logical-volume 705. Therefore, in the directory 801 of FIG. 36, the storage area of the data of the page 1 of the volume number LV1 which corresponds to the snapshot duplicate volume 702 is rewritten from “the volume number LV0, page 2” of FIG. 34 to “the volume number LV0, page 1” of FIG. 36. The value 0 for indicating that it is unused is set in the section of the page 2 of the volume number LV0 which corresponds to the common logical-volume 705 in the common logical-volume held-data managing table 802 of FIG. 36 since the page 3 of the common logical-volume 705 is unused in the first place as shown in FIG. 33 and there is no data to be located in the page 2 of the volume number LV0. Thus, where the data has already been stored in the page 3 and thereafter of the common logical-volume 705, naturally, the value 1 indicating that it is being used is maintained as it is in the section of the page 2 of the volume number LV0 in the common logical-volume held-data managing table 802 of FIG. 36. The relocating processing of the data by the data arranging device 2204 has been described above by referring to the operation of the case as the simplest example, in which the data for one page within the common logical-volume 705 as the real data storage area is deleted. However, even in the case where the data of a plurality of the pages are deleted from the common logical-volume 705, it is possible to generate a contiguous storage area by relocating all the data within the common logical-volume 705 for putting them together on the front page side and releasing the page on the rear side through repeating the relocating processing in which the pages after the vacant page are all shifted by one page regardless of the presence/non-presence of data by searching the page of the common logical-volume 705 and repeatedly executing the processing completely the same as the one described above every time the vacant page is detected. Further, in practice, in consideration of the processing time required for relocating the data, it is possible to shift the data for the corresponding number of the vacant pages in order from the data on the front side by obtaining the number of the vacant pages located in the position closer to the front side than the respective page by each of the used pages through collectively detecting the unused pages by searching the page of the common logical-volume 705 from the front. In this case, for example, if each of the page 0, page 1, page 2, page 3, page 4, page 5,—is unused, unused, used, unused, used, used—, respectively, the number of the vacant pages corresponding to the used page 2 is two pages, the number of the vacant pages corresponding to the used page 4 is three pages, and the number of the vacant pages corresponding to the used page 5 is three pages. Thus, first, the data of the used page 2 is being shifted by two pages on the superior side to be written in the page 0. Then, the data of the used page 4 is being shifted by three pages on the higher side to be written to the page 1 and, further, the data of the used page 5 is being shifted by three pages on the higher side to be written to the page 2. The arranging processing performed by the data arranging device 2204 may be executed in the background so as not to disturb the IO processing from the host. In the case where the arranging processing is performed in the background, the processing for detecting the dispersion of the unused pages may be executed by an arbitrarily set schedule and the arranging processing may be automatically started at the stage where the dispersion (fragmentation) of the unused pages exceeds the set limitation. The present invention can be utilized for backup and the like of the volume level in the disk array subsystem. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to storing data into a storage device of a disk array subsystem and the like and, especially, to a duplicate data storing system, a duplicate data storing method, and a duplicate data storing program, which enable to improve an effective usage of the storage device capacity in a duplicate data storage area at the time of using snapshot technique while maintaining the disk-access performance. 2. Description of the Related Art When backing up the volume which constitutes a duplicate data storage area in a storage device of a disk array subsystem and the like, the volume as a backup target is duplicated inside the disk array subsystem and a backup server stores data read out from the duplicate data storage area to be the duplicate volume to a backup medium such as a tape drive. As the method for duplicating the volume, conventionally used is a method in which a complete duplicate of the backup target volume is formed. Naturally, in this case, it takes time which is proportional to the storage capacity of the volume of the backup target for completing the duplication of the volume. For increasing the use efficiency of the backup-target volume, Japanese Patent Unexamined Publication No. 2001-318833 discloses a technique in which a plurality of volumes are used around so as to select a duplicate volume appropriate for the capacity of the backup-target volume. This technique does not enable to shorten the time used for duplicating the volume. Also, it is necessary to reserve a plurality of the duplicate volumes for functioning as the duplicate data storage areas in advance to be used for backup, which causes such a shortcoming that the required storage capacity becomes redundant. Recently, in accordance with a remarkably increasing trend of reduction in backup window (system suspension time for backup processing), a technique such as snapshot or shadow copy has been put in use for duplicating the volume. The snapshot herein is a technique for maintaining the state of the volume as the snapshot-target volume at the time when being designated. For example, if a snapshot of the snapshot-target volume as shown in FIG. 1 ( a ) in which data is stored is taken, first, a snapshot duplicate volume having a storage capacity equivalent to that of the snapshot-target volume is generated in a storage device in the manner as shown in FIG. 1 ( a ). At a stage of writing data “EE” to a storage area of data “BB” of the snapshot-target volume, the data “BB” before update is stored in the same address of the snapshot duplicate volume in the manner as shown in FIG. 1 ( b ), and the snapshot duplicate volume functions as a first-generation snapshot. At this time, if another snapshot of the snapshot-target volume is taken once again, a snapshot duplicate volume having the storage capacity equivalent to that of the snapshot-target volume is newly generated in the storage device in the manner as shown in FIG. 1 ( b ), and the snapshot duplicate volume functions as a second-generation snapshot. Further, if it is desired to write data “FF” in a storage area of data “CC” of the snapshot-target volume, the data “CC” before update is stored in the same address of the snapshot duplicate volume which functions as a second-generation snapshot in the manner as shown in FIG. 1 ( c ), while the content of the snapshot duplicate volume which functions as the first-generation snapshot is being held as shown in FIG. 1 ( b ) or FIG. 1 ( c ). Here, a series-type snapshot has been briefly described by referring to FIG. 1 ( a ) to FIG. 1 ( c ). In the case where a parallel-type snapshot is applied, when writing the data “FF” in the storage area of the data “CC” of the snapshot-target volume in the manner as shown in FIG. 1 ( c ), the data “CC” is stored also in the first-generation snapshot in addition to the second-generation snapshot. In the volume duplicating method utilizing the snapshot technique, it may simply define the volume for holding only the update data to the backup-target volume right after the disk array subsystem receives a snapshot command. Thus, the backup-target volume can be seemingly duplicated at instant. Hereinafter, in the backup of the volume using the snapshot technique, the volume for storing an original data as the backup target is referred to as the snapshot-target volume, and the volume to be the duplicate data storage area for holding the update data of the backup-target volume is referred to as the snapshot duplicate volume, respectively. The use of the snapshot technique in the backup processing is only an example, and the snapshot technique is utilized in other various situations in the operation of the disk array subsystem. An example of a conventional data storing system for the snapshot duplicate volume using the snapshot technique will be specifically described by referring to FIG. 2 to FIG. 9 . A conventional disk array subsystem 100 comprises: a device (logical-volume property managing table, 201 in FIG. 3 ) for judging by each logical-volume whether the logical-volume is the snapshot-target volume, the snapshot duplicate volume, or a volume of any other property; a device (logical-volume conversion table, 202 in FIG. 3 ) for address-converting a read-command or write-command which is issued by a host by designating the logical-volume into another logical-volume as the inner operation; and a device (held-data managing table, 203 in FIG. 3 ) for judging whether or not the snapshot duplicate volume holds the data required by the read-command or the write-command. The data held in the snapshot duplicate volume is managed in a size peculiar to the disk array subsystem 100 , so that the read-command or the write-command from the host is divided into the peculiar management units described above by an IO monitoring device ( 400 in FIG. 7 ) to be processed by each management unit. FIG. 4 , FIG. 5 , and FIG. 6 illustrate the process of forming the duplicate of the volume and performing reading or writing from/to the volume in the disk array subsystem 100 employing the above-described data storing system. As the process for duplicating the volume, first, as shown in FIG. 4 , the snapshot-target volume and the snapshot duplicate volume having at least the same storage capacity as that of the snapshot-target volume are formed within the disk array subsystem in a step 3 a 00 . FIG. 2 shows the state of this process. In this example, two logical-volumes, that is, a logical-volume LV 0 and a logical-volume LV 1 are formed in the disk array subsystem 100 . When the disk array subsystem receives a snapshot command having a parameter which indicates that the logical-volume LV 0 is the snapshot-target volume and the logical-volume LV 1 is the snapshot duplicate volume in a next step 3 a 01 , the logical-volume property managing table 201 , the logical-volume conversion table 202 , and the held-data managing table 203 are initialized in a step 3 a 02 . That is, the snapshot-target property is given to the logical-volume LV 0 and the snapshot-duplicate property to the logical-volume LV 1 in the logical-volume property managing table 201 . In the logical-volume conversion table 202 , LV 1 is set as a logical-volume number after conversion corresponding to the logical-volume LV 0 , LV 0 is set as a logical-volume number after conversion corresponding to the logical-volume LV 1 , and a value 0 indicating that the snapshot duplicate volume holds no data is set in the snapshot duplicate volume (that is, the logical-volume LV in this case) in the held-data managing table 203 . The state of each table at this time is shown in FIG. 3 . Next, described is a procedure of the processing performed at the time when the disk array subsystem 100 having the snapshot-target volume LV 0 and the snapshot duplicate volume LV 1 as described in the aforementioned procedure of volume duplicate receives the write-command and read-command. First, described is the processing process at the time of receiving the write-command ( 505 in FIG. 8 ). A microprocessor (simply referred to as CPU hereinafter) of the disk array subsystem 100 refers to the logical-volume property managing table 201 in a step 3 b 00 shown in FIG. 5 for judging whether the received command is a command for the snapshot-target volume or for the snapshot duplicate volume. The processing is completed without writing data when it is judged to be the write-command to the snapshot duplicate command in a step 3 b 01 . This is the processing of the case where it is used to maintain the duplicate of the snapshot-target volume in the state of the point where the snapshot command is received in the snapshot duplicate volume, e.g., the processing for backup and the like. In other use data may be written onto the snapshot duplicate volume as requested by the write-command. In the meantime, when it is judged to be the write-command for the snapshot-target volume in a step 3 b 01 , the CPU refers to the logical-volume conversion table 202 in a step 3 b 02 and specifies the snapshot duplicate volume as a pair of the snapshot-target volume. In a step 3 b 03 , it is judged from the held-data managing table 203 whether there is data in the write-request address of the specified snapshot duplicate volume. When it is judged that the there is the data in the snapshot duplicate volume LV 1 , the data is written to the snapshot-target volume LV 0 in a step 3 b 07 and the processing is completed. When it is judged that there is no data in the snapshot-target volume LV 1 , the data already stored in the write-request address of the snapshot-target volume LV 0 is copied to the same address of the snapshot duplicate volume LV 1 in a step 3 b 05 . Then, a value 1 indicating that there is data in this area of the held-data managing table 203 is set in a step 3 b 06 , and the data is written to the snapshot-target volume LV 0 in a step 3 b 07 . Thereby, the processing is completed. Next, described is a procedure of the processing performed at the time of receiving the read-command ( 506 in FIG. 8 ). The CPU refers to the logical-volume property managing table 201 in a step 3 c 00 shown in FIG. 6 for judging whether the received command is a command for the snapshot-target volume LV 0 or a command for the snapshot duplicate volume LV 1 . When it is judged to be a command for the snapshot-target volume LV 0 in a step 3 c 01 , the data is read out from the snapshot-target volume LV 0 , and the processing is completed. In the meantime, when it is judged to be a command for the snapshot duplicate volume LV 1 in a step 3 c 01 , reference is made to the held-data managing table 203 in a step 3 c 02 , and it is judged in a step 3 c 03 whether or not there is data in a read-out require address of the snapshot duplicate volume LV 1 . When it is judged that there is data in the snapshot duplicate volume LV 1 , the data is read out from the snapshot duplicate volume LV 1 and the processing is completed. When it is judged that there is no data in the snapshot duplicate volume LV 1 , reference is made to the logical-volume conversion table 202 in a step 3 c 04 and recognizes the snapshot-target volume LV 0 as a pair of the snapshot duplicate volume LV 1 . Then, the data is read out from the specified snapshot-target volume LV 0 and the processing is completed. A first drawback of the above-described conventional art is that the use efficiency of the storage capacity is bad. The reason is that it is necessary in the data storing system of the snapshot duplicate volume in the conventional disk array subsystem to make a snapshot duplicate volume having at least the same storage capacity as that of the snapshot-target volume in spite that only the update data of the snapshot-target volume generated after receiving the snapshot command is copied to the snapshot duplicate volume. That is, in the above-described conventional art, data-copy from the snapshot-target volume to the snapshot duplicate volume has to be performed by the same address so that, logically, the snapshot duplicate volume is limited to be in the same configuration as that of the snapshot-target volume. A second drawback is that the data reading-out efficiency from the snapshot duplicate volume is bad. The reason is that, in the data storing system of the snapshot duplicate volume in the conventional disk array subsystem, the data-copy from the snapshot-target volume to the snapshot duplicate volume is symmetrically performed in between the volumes having logically the same configuration with the same address being the parameter. Accordingly, when the data-copy from the snapshot-target volume to the snapshot duplicate volume is generated in the scattered addresses, naturally, the data held in the snapshot duplicate volume becomes the scattered data. Thus, the effect of pre-fetching from a physical disk cannot be expected at all. An object of the present invention is to provide a duplicate data storing system, a duplicate data storing method, and a duplicate data storing program for enabling to form a duplicate volume which consumes a storage capacity proportional to an update data amount of a snapshot-target volume after receiving a snapshot command in a storage device such as a disk array subsystem. | <SOH> SUMMARY OF THE INVENTION <EOH>The duplicate data storing system of the storage device according to the present invention achieved the above-described object through a feature which comprises a real data storage area for storing data to be written to a duplicate data storage area which is virtually built within the storage device; a data-storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area; and a data-storage area managing device for managing stored areas of data in the duplicate data storage area within the real data storage area. With the above-described configuration, the data to be written to the duplicate data storage area within the storage device at the time of updating the original data are all stored in the real data storage area. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate volume which requires the storage capacity equivalent to that of the volume for storing the original data. In other words, the duplicate data storage area of the present invention is only the area virtually built in the storage device and, substantially, it is formed by a data storage area managing device which manages where, in the real data storage areas, the data to be written to the duplicate data storage area is stored. The data storage area managing device is a kind of index table so that the storage capacity required for building the data storage area managing device is extremely small. The above-described configuration contains additionally a data-storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area. When the data is written to the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement for storing the data in order. Therefore, there is no vacant area to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. In addition to the above-described configuration, it is possible to provide a held-data managing device for managing a use state of the real data storage area and a real data storage area expanding device for increasing a storage capacity of the real data storage area. The use state of the real data storage area is managed by the held-data managing device and the storage capacity of the real data storage area can be increased by the real data storage area expanding device as necessary. Therefore, it is possible to surely store the data in the real data storage area even though the initial capacity of the real data storage area is set relatively small. More specifically, as the real data storage area expanding device, it is possible to employ a configuration in which the real data storage area itself is expanded for increasing the storage capacity. Such configuration is effective in the case where there are contiguous unused storage areas present in the real data storage area within the storage device. Further, the real data storage area expanding device may be so constituted to generate a new real data storage area within the storage device in addition to the real data storage area which has already been provided. In the case of employing such configuration, it is possible to increase the storage capacity of the real data storage area by additionally forming a new real data storage area in the unused storage area even when there is not a sufficient contiguous unused storage area present in the real data storage area, as long as there is a reasonable unused storage area present within the storage device. Here, one or more of the real data storage areas may be provided for storing data in all the duplicate data storage areas within the storage device to the one or more of the real data storage area. As described above, the data storage area managing device clearly specifies the correlation which indicates where the data to be written to the duplicate data storage area is stored in the real data storage area. Therefore, even there are a plurality of duplicate data storage areas and real data storage areas present within the storage device, there is no specific drawback to be caused in storing data and in specifying the storage areas and it enables to precisely correspond to the system with various volume structures. For example, by dividing the duplicate data storage area within the storage device into a plurality of groups; providing one or more of the real data storage areas for each of the groups; and, further, providing a device having a list of the duplicate data storage areas and the real data storage areas belonging to the groups to each of the groups, it is possible to store data of the duplicate data storage area within the group in the one or more of the real data storage areas within the group. In the case where such configuration is employed, the device for holding a list of the duplicate data storage areas and the real data storage areas functions as a part of the above-described data storage area managing device, which enables to precisely manage where the data to be written to the duplicate data storage area is written in the real data storage area in regards to the correlation between a plurality of the duplicate data storage areas and a plurality of the real data storage areas. It is possible that the required capacity of the real data storage area as the entire duplicate data storage areas which are put into a group can be estimated in advance. Thus, in the case where there is an upper limit in the storage capacity of a physical recording medium to which the real data storage area is provided, it is possible to effectively utilize the physical recording media such as hard disks and the like through optimizing a combination of the duplicate data storage areas as one group, or optimizing the number or the combination of the real data storage areas or the physical recording media corresponding to the group. It may comprise an alarm generating device for generating an alarm which encourages an increase of the real data storage area when a used storage capacity of the real data storage area exceeds an alarm generating threshold value by setting the alarm generating threshold value for the real data storage area. In the case where such configuration is employed, an alarm is generated before there is a shortage of the capacity generated in the real data storage area. Thus, by actuating the real data storage area expanding device at this point, a shortage of the capacity in the real data storage area can be prevented beforehand. More specifically, it is desirable to be in a configuration in which the real data storage area expanding device is actuated by an inside processing of the storage device by detecting the alarm from the alarm generating device. By employing such configuration, the data storage area expanding device operates when the used storage capacity of the real data storage area exceeds the alarm generating threshold value and the real data storage area is automatically increased. Therefore, it is possible to surely prevent the shortage of the capacity in the real data storage area. Further, at the stage of storing the data in the real data storage area, it is always guaranteed that there is a sufficient storage capacity in the real data storage area, so that it is possible to write the data in the real data storage area immediately. Thus, it enables to overcome shortcomings such as a decrease in the processing speed due to the waiting time generated in accordance with expansion or generation of the real data storage area and so on. Specifically, as for the above-described held-data managing device, the main part can be formed by a table which indicates the presence of data by each memory unit being obtained by dividing the storage area of the real data storage area. The held-data managing device may simply indicate only the presence of the data so that the required minimum memory unit may be 1 bit, for example. Thus, there is no shortcoming such as waste of the storage capacity and so on caused by providing the held-data managing device. Further, time required for referring to the held-data managing device is very short so that there is almost no bad effect such as delay in the inside processing being caused by referring to the table. The held-data managing device may be formed by: a table for indicating presence of data by each of the memory units which are obtained by dividing the storage area of the real data storage area; a table for indicating presence of data by a memory unit group in which a plurality of the memory units are put together; and a table with a plurality of hierarchies in which a plurality of the memory unit groups are put together for indicating presence of data of each group. There are various sizes of the data stored in the real data storage area, and for storing such data in the real data storage area, it may be necessary to divide the data under various conditions. Specifically, for example, there are concepts such as the minimum memory unit (page) determined according to the structure or format of the physical recording medium to which the real data storage area is provided and a memory unit group (segment) in which a plurality of memory units are put together. By utilizing the hierarchy table formed in accordance with the structure of such storage area as the held-data managing device, the time required for checking the presence of the data in the storage area of the real data storage area and, further, the time for required for reading/writing the data can be dramatically shortened. For example, in the case where contiguous data is stored over a plurality of pages, it is unnecessary to check the presence of data by each page but the presence of the data in the segment in which the pages are grouped into may be simply checked. Also, reading and writing of data can be achieved by a single access. The data storage area managing device may be formed by mapping the storage area of the real data storage area on the duplicate data storage area side. As described above, there is no physical limit in the relation between the real data storage area and the duplicate data storage area. However, when storing the data to the real data storage area, first, an access is made from the host side to the duplicate data storage area so that by mapping the data storing area managing device to be referred on the duplicate data storage area side, it is highly possible that the processing speed can be improved. Specifically, the data storage area managing device is formed to include a table for mapping the storage area of the real data storage area on the duplicate data storage area side and to obtain an address conversion information for the real data storage area from an entry of the table. The table is not for storing the real data but for storing only the address conversion information. Thus, like the above-described held-data managing device, shortcomings such as waste of the storage capacity and so on are not to be caused. Inversely, it is possible to form the data storage area managing device by mapping the storage area of the duplicate data storage area on the real data storage area side. In this case, the data storage area managing device is formed to include a table for mapping the storage area of the duplicate data storage area on the real data storage area side and to obtain address conversion information for the real data storage area from an entry of the table. Further, it is possible to employ a configuration comprising a memory unit managing device for managing memory units set in the real data storage area, wherein the data storage area determining device comprises: a communication device for communicating with a corresponding storage area managing table which obtains the data section held by a duplicate data storage area; a communication device for communicating with an IO monitoring device which obtains an IO size of a read-command or write-command for the duplicate data storage area; and an unused area searching device for detecting an available memory unit in a real data storage area through searching the held-data managing device. By employing such configuration, the data storage area determining device can obtain the IO size of the write-command from the IO monitoring device through the communication device, and also can check the memory unit which is set by the memory unit managing device. Therefore, based on the IO size as a unit of writing data and the memory unit of the storage area in the real data storage area, the available storage area in the real data storage area can be precisely detected by the unused area searching device for storing the data. Likewise, when reading out the data, the IO size of the read-command can be obtained from the IO monitoring device through the communication device. Accordingly, based on the IO size as a unit for reading the data or the memory unit, it is possible to precisely read out the data as a target of reading from the duplicate data storage area by referring to the corresponding storage area managing table. Here, it is desirable that the unused area searching device be so constituted that an available storage unit is detected by selecting the real data storage area according to an IO size of a command for the duplicate data storage area. In the case where a plurality of the real data storage areas with different memory units are used together, the available storage area is to be detected by selecting the real data storage area according to the IO size so that the storage capacity of the real data storage area can be most effectively utilized. It is possible to form the memory unit managing device so as to manage the memory units set in each of the real data storage areas. In the case where such configuration is employed, in the memory unit managing device, the memory unit used regularly in each of the real data storage areas is stored for the numbers of the real data storage areas. Accordingly, the data storage area determining device can store the data through precisely detecting the available storage area in the real data storage area by the unused area searching device, after selecting the real data storage area which fits the IO size based on the IO size as a unit of writing the data or the memory unit of each real data storage area. Therefore, it enables to achieve the effective use of the storage capacity of the real data storage area. Also, it is possible to form the memory unit managing device so as to manage the memory units set in each area which is obtained by dividing the real data storage area. In the case where such configuration is employed, in the memory unit managing device, several kinds of available memory units are to be stored in a single real data storage area. Accordingly, the data storage area determining device can store the data through precisely detecting the storage area having the memory unit corresponding to the IO size as a unit of writing data from the real data storage area by the unused area searching device. In this case, the size of the storage area in the real data storage area is not fixed but there area several kinds of sizes being mixed. Therefore, for storing the data, the storage area having the memory unit corresponding to the IO size is to be always selected so that it enables to achieve the effective use of the storage capacity of the real data storage area. Further, in addition to each of the above-described configurations, it is possible to provide a data arranging device for rearranging data by each of the real data storage areas. By employing such configuration, it is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. Further, it is desirable that the data arranging device be formed to rearrange data automatically when it is detected that the data sections held in the real data storage areas are non-contiguous. It is possible to shorten the time required for rearranging the data by rearranging the data before a strong fragmentation is generated. A duplicate data storing method of a storage device achieves the same above-described object by a configuration, comprising the steps of: determining a next storage area to be used in a contiguous arrangement within a real data storage area when duplicating data from a duplicate data storage area to the real data storage area which is for storing the data of the duplicate data storage area being virtually built within a storage device; and managing a correlation which indicates where, in the real data storage area, data of the duplicate data storage area is stored through storing it within the storage device. With the above-described configuration, the data to be written to the duplicate data storage area within the storage device at the time of updating the original data are all stored in the real data storage area. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate data storing method which requires a duplicate volume having the storage capacity equivalent to that of the volume for storing the original data. The real data is not stored in the duplicate data storage area so that it is necessary to manage the correlation between the virtual duplicate data storage area and the real data storage area which is for storing the real data by storing the corresponding relation within the storage device. However, the storage capacity required for building the data storage area managing device is extremely small so that there is no waste of the storage capacity being caused. Further, when the data is duplicated in the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement. Therefore, there is no vacant area to be generated carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. Further, a storage capacity of the real data storage area may be increased when a used storage capacity exceeds a threshold value by monitoring the used storage capacity of the real data storage area. It is possible to increase the storage capacity of the real data storage area as necessary by monitoring the use state of the real data storage area. Thus, it is possible to surely store the data in the real data storage area even through the initial capacity of the real data storage area is set relatively small. It may be configured to rearrange the data within the real data storage area by detecting that data held in the real data storage area is non-contiguous. It is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. A duplicate data storing program of the present invention is a duplicate data storing program for storing data of a duplicate data storage area which is virtually built within a storage device in a real data storage area within the storage device, which achieves the above-described same object by a configuration wherein: a microprocessor provided within the storage device is made to function as a data storage area determining device for determining a next storage area to be used in a contiguous arrangement in the real data storage area so as to store data in the real data storage area; and also is made to function as a data storage area managing device for managing where, in the real data storage area, data of the duplicate data storage area is stored. The microprocessor provided within the storage device functions as the data storage area determining device and stores the data in order by determining the next storage area to be used in a contiguous arrangement when storing the data in the duplicate data storage area which is virtually built within the storage device to the real data storage area within the storage device. Thus, the vacant areas are not to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved. Thereby, the reading-out efficiency of data from the duplicate volume by pre-fetch can be improved. The storage capacity required for the real data storage area is the amount corresponding to the data amount to be actually updated. Thus, the storage capacity of the real data storage area which functions as a substantial duplicate volume can be largely reduced compared to the conventional duplicate volume which requires the storage capacity equivalent to that of the volume for storing the original data. Further, the microprocessor provided within the storage device also functions as the data storage area managing device and manages where, in the real data storage area, the data to be written to the duplicate data storage area is stored. Since it is necessary for management, a kind of index table which forms the main part of the data storage area managing device is generated within the storage device. However, the storage capacity required for building the table is extremely small so that it is not a factor for disturbing the effective use of the storage capacity. Further, it may be so formed that the microprocessor within the storage device is made to function as a real data storage area expanding device by the duplicate data storing program. It is possible to increase the storage capacity of the real data storage area as necessary at the point where the used storage capacity exceeds the threshold value by monitoring the use state of the real data storage area. Thus, it is possible to surely store the data in the real data storage area even through the initial capacity of the real data storage area is set relatively small. Further, it is possible that the microprocessor within the storage device is made to function as a data arranging device by the duplicate data storing program. The data within the real data storage area is rearranged at the stage of detecting that the data section held in the data storage area is non-contiguous. Thus, it is possible to achieve a more effective use of the storage capacity of the real data storage area by eliminating the fragmentation generated by deletion of the data and the like. In the present invention, only the data to be updated in the volume for storing the original data is to be stored in the real data storage area which substitutes the snapshot duplicate volume. Thus, compared to the conventional duplicate data storing system and the duplicate data storing method in which the data is stored by utilizing the duplicate volume having the storage capacity equivalent to the storage capacity of the volume to which the original data is stored, it is possible to dramatically reduce the storage capacity of the real data storage area which functions as a substantial duplicate volume. Further, when writing the data to the real data storage area, the data storage area determining device determines the next storage area to be used in a contiguous arrangement for storing the data in order. Therefore, there is no vacant area to be formed carelessly in the real data storage area so that the storage capacity of the real data storage area can be saved and the data reading-out efficiency from the duplicate volume by pre-fetch can be improved. Also, the data storage area managing device clearly specifies the correlation which indicates where the data to be written to the duplicate data storage area is stored in the real data storage area. Therefore, even there are a plurality of duplicate data storage areas and real data storage areas present within the storage device, there is no specific drawback to be caused in storing data and in specifying the storage area and it enables to precisely correspond to the system with various volume structures. | 20050121 | 20100406 | 20050728 | 65349.0 | 0 | YU, JAE UN | DUPLICATE DATA STORING SYSTEM, DUPLICATE DATA STORING METHOD, AND DUPLICATE DATA STORING PROGRAM FOR STORAGE DEVICE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,292 | ACCEPTED | Illumination modulation technique for microdisplays | A projection display may use pulse width modulation wherein the duty cycle may be varied. This duty cycle variation may improve bit depth in some embodiments. For example, on alternate frames, the duty cycle may be reduced by a given percentage. | 1. A method comprising: pulse width modulating the duty cycle of a light beam to establish a pixel intensity; and varying the duty cycle between two frames. 2. The method of claim 1 including reducing the duty cycle for a darker pixel relative to a lighter pixel. 3. The method of claim 1 including varying the duty cycle in a successive frame. 4. The method of claim 3 including changing the duty cycle in every other frame. 5. The method of claim 1 including alternating between two duty cycles in successive frames. 6. The method of claim 5 including providing a 50% duty cycle for a first set of frames, and reducing the duty cycle in another set of frames. 7. The method of claim 6 including reducing the duty cycle between about 2 and about 10%. 8. The method of claim 1 including alternating the duty cycle using a modulo function. 9. The method of claim 8 including providing a lookup table to determine how to reduce the duty cycle. 10. The method of claim 9 including providing different intensity values for different pixels and adjusting the duty cycle based on a frame number. 11. A projection display comprising: a spatial light modulator; and a device to vary the duty cycle of pulse width modulation between two frames. 12. The display of claim 11 wherein said device to reduce the duty cycle for a darker pixel relative to a lighter pixel. 13. The display of claim 11 wherein said device to vary the duty cycle in successive frames. 14. The display of claim 13 wherein said device to change the duty cycle in every other frame. 15. The display of claim 11 wherein said device to alternate the duty cycles in successive frames. 16. The display of claim 15 wherein said device to provide a 50% duty cycle in a first set of frames and reduced duty cycles in another set of frames. 17. The display of claim 16 wherein said device to reduce the duty cycle selectively between about 2 and about 10%. 18. The display of claim 11 wherein said device to implement a modulo function to reduce the duty cycle. 19. The display of claim 18 wherein said device includes a lookup table to determine how to reduce the duty cycle. 20. The display of claim 19 wherein said device tp provide different intensity values for different pixels and adjust the duty cycle based on the frame number. 21. A spatial light modulator comprising: a modulating panel; and a device to vary the duty cycle of pulse width modulation of said modulator between successive frames. 22. The modulator of claim 21, said device to reduce the duty cycle for a darker pixel relative to a lighter pixel. 23. The modulator of claim 21, said device to vary the duty cycle in successive frames. 24. The modulator of claim 23 wherein said device to change the duty cycle in every other frame. 25. The modulator of claim 21, said device to alternate the duty cycles in successive frames. | BACKGROUND This invention relates generally to microdisplays. A projection display system typically includes one or more spatial light modulators (SLMs) that modulate light for purposes of producing a projected image. The SLM may include, for example, a liquid crystal display (LCD) such as a high temperature polysilicon (HTPS) LCD panel or a liquid crystal on silicon (LCOS) microdisplay, a grating light valve or a MEMs (where “MEMs” stands for micro-electro-mechanical devices) light modulator such as a digital mirror display (DMD) to modulate light that originates from a lamp of the projection display system. In typical projection display systems, the lamp output is formatted with optics to deliver a uniform illumination level on the surface of the SLM. The SLM forms a pictorial image by modulating the illumination into spatially distinct tones ranging from dark to bright based on supplied video data. Additional optics then relay and magnify the modulated illumination pattern onto a screen for viewing. The SLM typically includes an array of pixel cells, each of which is electrically controllable to establish the intensity of a pixel of the projected image. In some projection display systems, SLMs are transmissive and in others, they are reflective. For the purposes of simplification, the discussion will address reflective SLMs. An SLM may be operated so that each pixel has only two states: a default reflective state which causes either a bright or a dark projected pixel and a non-default reflective state which causes the opposite projected pixel intensity. In the case of an LCOS SLM, the pre-alignment orientation of the LC material and any retarders in the system determine whether the default reflective state is normally bright or normally dark. For the purposes of simplification, the discussion will denote the default reflective state as normally bright, i.e., one in which the pixel cell reflects incident light into the projection lens (the light that forms the projected image) to form a corresponding bright pixel of the projected image. Thus, in its basic operation, the pixel cell may be digitally-controlled to form either a dark pixel (in its non-default reflective state) or a bright pixel (in its default reflective state). In the case of a DLP SLM, the states may represent the pixel in a co-planar position to the underlying substrate. Although its pixels are operated digitally, the above-described SLM may also be used in an application to produce visually perceived pixel intensities (called “gray scale intensities”) between the dark and bright levels. For such an application, each pixel may be controlled by pulse width modulation (PWM), a control scheme that causes the human eye to perceive gray scale intensities in the projected image, although each pixel cell still only assumes one of two states at any one time. The human visual system perceives a temporal average of pixel intensity when the PWM control operates at sufficiently fast rates. In the PWM control scheme, a pixel intensity (or tone) is established by controlling the time that the pixel cell stays in its reflective state and the time that the pixel cell remains in the non-reflective state during an interval time called a PWM cycle. This type of control is also referred to as duty cycle control in that the duty cycle (the ratio of the time that the pixel cell is in its reflective state to the total time the pixel cell is in its non-reflective and reflective states) of each PWM cycle is controlled to set the pixel intensity. A relatively bright pixel intensity is created by having the pixel cell spend a predominant proportion of time in its reflective state during the PWM cycle, while a relatively dark pixel intensity is created by having the pixel cell spend a predominant amount of time in its non-reflective state during the PWM cycle. The quality of the projected image typically is a function of the number of possible gray scale intensities, also called the “bit depth.” For the above-described PWM control scheme, a bit depth of “N” means that the PWM cycle is divided into 2N time consecutive and non-overlapping time segments. For a particular PWM cycle, each of the time segments in which the pixel cell is in its reflective state contributes to the overall luminance of the corresponding pixel. Each time segment of the PWM cycle typically corresponds in duration to the cycle of a clock signal. Thus, the larger the number of time segments (i.e., the greater the number of gray scale intensities), the higher the frequency of this clock signal, thereby requiring a high speed clock to form the pixel gray scale or tonal range. Power consumption is also a function of this clock frequency and also increases with bit depth. Other factors may increase the clock rate needed for a particular bit depth. For example, for a three SLM LCD panel projection system (one SLM for each primary color), the PWM cycle may have a period that is equal to one half of the video data's field time (typically 1/60 second). Opposite drive voltage polarities are needed in LCD systems to prevent voltage bias accumulation. This is well known for liquid crystal display systems. Thus, LCD SLM devices require two PWM cycles in each video data field. This doubles the clock rate requirement. For a two SLM panel projection system where one of the SLM panels is temporally shared by two primary colors, the video frame time must be split to allocate PWM cycles to each primary color, thereby increasing the needed PWM clock rate if the same bit depth is maintained in all colors. For a one SLM panel projection system with an SLM panel temporally shared by all three primary colors, the video frame time must be further subdivided. For an LCOS SLM the video frame time would be divided into six PWM cycles, a pair for each primary color. The PWM clock period may have an even shorter duration when the unequal length PWM cycles are needed to adjust the display white point. Since common projection lamps are rich in blue and weak in red output, it is generally necessary to devote longer portions of the video frame time to red to achieve white balance. This necessitates the PWM clock period to be increasingly small and the clock frequently and power consumption to be increasingly high. Thus, there is a need for modulation techniques that improve bit depth of microdisplays. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a projection display system according to an embodiment of the invention; FIG. 2 is a view of a light impinging face of a color filter wheel; FIG. 3 is a block diagram of an electrical system of the projection display system according to an embodiment of the invention; FIG. 4 is an illustration of a pulse width modulation control technique for a pixel cell according to an embodiment of the invention; FIG. 5 depicts relationships between pixel intensities and a table index value; FIG. 6 is a schematic depiction of the duty cycle modulating scheme in accordance with one embodiment of the present invention; and FIG. 7 is a timing diagram showing the duty cycle for a pixel and an altered duty cycle for the pixel in a different frame. DETAILED DESCRIPTION Referring to FIG. 1, a projection display system 10 in accordance with an embodiment of the invention includes one or more spatial light modulators (SLMs) 24 (one shown in FIG. 1) that modulate impinging light to produce a projected composite, color optical image (herein called “the projected image”). The SLM 24 may be a liquid crystal (LC) SLMs, a tilt-mirror SLM, or a MEMs-type SLM, depending on the particular embodiment of the invention. Unless otherwise stated, embodiments described herein use LC SLMs for purposes of simplifying the description. However, it is understood that other SLMs, such as grating light valve, HTPS, or other technology SLMs, may be used, in other embodiments of the invention. Furthermore, unless otherwise noted below, the projection display system 10 includes a single SLM 24, for purposes of simplifying the following description, although other projection systems that have multiple SLMs may be alternatively used and are within the scope of the appended claims. In accordance with some embodiments of the invention, the projection display system 10 includes a lamp 12 (a mercury lamp, for example) that produces a broad visible spectrum illumination beam that passes through an ultraviolet/infrared (UV/IR) filter 14 of the system 10. The light passing from the filter 14, in turn, passes through a rotating color wheel, such as a color wheel 18 that is also depicted in FIG. 2. Referring to FIG. 1 in conjunction with FIG. 2, a function of the color wheel 18 is to serve as a time-varying wavelength filter to allow certain wavelengths of light to pass therethrough at the appropriate times so that the filtered light may be modulated by the SLM 24 to produce the projected image. More specifically, in some embodiments of the invention, the projection display system 10 may be a shared color system, a system in which, for example, the SLM 24 modulates red, followed by green, followed by blue light. Thus, the SLM 24 is temporally shared to modulate different primary color beams. In such a shared color projection display system, a light impinging face of the color filter wheel 18 may be, as depicted in FIG. 2, generally divided so that one arcuate region 28 of the wheel 18 serves as a wavelength filter to select certain wavelengths of light and other arcuate regions 29 and 30 of the wheel 18 select other wavelengths of light. The light from the UV/IR filter 14 (FIG. 1) is incident on a “spot” on an outer circular track of the color wheel 18, a track that coincides with the arcuate regions 28, 29 and 30. A non light-filtering and central interior region 27 of the color wheel 18 does not receive the beam from the UV/IR filter 14. The region 27 may receive a spindle (not shown) that is connected to a motor (not shown) for purposes of rotating the wheel 18 to filter light from UV/IR filter 14 via one of the arcuate regions 28, 29 and 30. Thus, the light beam that is incident upon the color filter wheel 18 is eccentric with respect to the center of the wheel 18 so that the light beam is incident on one of the arcuate regions 28, 29 and 30 at any one time as the wheel 18 rotates. Various techniques (techniques using optical sensors, optical shaft encoders on the shaft of the motor, etc.) may be used to synchronize the rotation of the color wheel 18 with the modulation that is performed by the SLMs 24. More specifically, in some embodiments of the invention (further described below), the projection display system 10 includes a synchronizer (not shown) to synchronize the rotation of the color wheel so that the portion of the color wheel through which the light beam passes is more opaque when the SLM 24 is displaying darker tones. As a more specific example of an embodiment of the color wheel, the arcuate region 28 of the color wheel 18 may be a magenta segment that allows red light to pass therethrough. For the phase of the color wheel's rotation in which the light from the UV/IR filter 14 passes through the arcuate region 28, the projection display system 10 (via a polarizing beam splitter 22 (FIG. 1)) directs the red light beam to the SLM 24 so that the SLM 24 modulates the red light. The arcuate region 29 of the color wheel may be a green segment that allows green light to pass. For the phase of the color wheel's rotation in which the light from the UV/IR filter 14 passes through the arcuate region 29, the projection display system 10 (via the beam splitter 22) directs the green light to the SLM 24. For the phase of the color wheel's rotation in which the light from the UV/IR filter 14 passes through the arcuate region 30, the projection display system 10 (via the beamsplitter 22) directs blue light to the SLM 24. As previously stated, the single-SLM configuration that is depicted in FIG. 1 is for purposes of example only. Thus, the projection display system 10 may be replaced by another projection display system, in other embodiments of the invention, such as a projection display system that includes three SLMS, one for each primary color (red, green and blue, for example) of the projected image. As another example, in some embodiments of the invention, red, green and blue light may be temporally shared on an SLM in a two SLM display projection system. Therefore, many variations are possible and are within the scope of the appended claims. Referring to FIG. 1, among its other components, the projection display system 10 includes homogenizing and beam shaping optics 20 that further shape and collimate the light that exits the color wheel 18, prepolarizes and directs the resultant beam to the polarizing beam splitter 22. The polarizing beam splitter (PBS) 22 separates the light from the color wheel 18 based on polarization. More specifically, assuming the single-SLM configuration described above, the polarizing beam splitter 22 directs the different color sub-bands of light (at different times) to the SLM 24. Once modulated by the SLMs 24, the polarizing beam splitter 22 directs the modulated beam through projection lenses 23 for purposes of forming the projected image. Depending on the particular embodiment of the invention, the SLM 24 may be a digital mirror device (DMD), liquid crystal display (LCD) device, or other pixelated SLM. In some embodiments of the invention, the SLM 24 is a liquid crystal on silicon (LCOS) device that includes a liquid crystal layer that is formed on a silicon substrate in which circuitry (decoders, control circuits and registers, for example) to control and operate the device is fabricated. In some embodiments of the invention, an electrical system 30 for the projection display system 10 (FIG. 1) may have a general structure that is depicted in FIG. 3. Referring to FIG. 3, the electrical system 30 may include a processor 32 (one or more microcontrollers or microprocessors, as examples) that is coupled to a system bus 34. The processor 32 communicates over the system bus 34 with a memory 36 (a flash memory, for example) of the electrical system 30. The memory 36 stores instructions 40 to cause the processor 32 to perform one or more of the techniques that are described herein, as well as a look-up table (LUT) 38. In some embodiments of the invention, the projection display system 10 (FIG. 1) operates the pixel cells of the SLM 24 in a digital fashion, in that each pixel cell at any one time is either in a reflective state or a non-reflective state. Gray scale intensities are achieved by pulse width modulation (PWM), a modulation technique that controls the optical behavior of the pixel cell during an interval of time called a PWM cycle to control the intensity of the corresponding pixel of the projected image. The PWM control regulates the amount of time that a particular pixel cell is in its reflective and non-reflective states during a PWM cycle for purposes of establishing a certain pixel intensity. The amount of time that the pixel cell is in each reflectivity state for a given pixel intensity value is established by the LUT 38, in some embodiments of the invention. It is noted that in some embodiments of the invention, the LUT 38 may represent a collection of LUTs, one for each primary color. For purposes of simplifying the discussion herein, only one LUT is assumed, unless otherwise stated. The LUT 38 indicates a PWM duty cycle for each potential pixel intensity value. Among its other features, the electrical system 30 may include a color wheel synchronization module 46 and a video data interface 31 that are coupled to the system bus 34. The color wheel synchronization module 46 can serves to assist in ensuring that the physical position of the color wheel 18 is aligned with the start of a PWM timing cycle. The video data interface 31 receives pixel intensity data that is mapped through LUT 38 to specify per pixel PWM data (to drive the SLM 24). In some embodiments of the invention, the LUT 38 includes a corresponding duty cycle entry for each unique pixel intensity value. The duty cycle entry indicates a duration that the pixel cell remains in its default reflective state during the PWM cycle to produce the desired pixel intensity. The pixel cell remains in the non-default reflective state during the remainder of the PWM cycle. In some embodiments of the invention, each table entry indicates a number of pulse width modulation (PWM) counts, or clock cycles, for each intensity value. These are the number of clock cycles that the pixel cell needs to remain in its default reflective state. For the remaining clock cycles of the PWM cycle (having a fixed duration, for example), the pixel cell is in its non-default reflective state. The PWM clock counts may be executed with the non-reflective portion first and the reflective portion second or with the reflective portion first and the non-reflective portion second. In other embodiments, fractions of the total reflective and non-reflective clock counts may be alternated during a PWM cycle. In any execution strategy, the LUT-prescribed time proportion remains consistent relative to the whole PWM cycle time. Referring to FIG. 3 in conjunction with FIG. 4, the processor 32, for a given video data value, retrieves the corresponding PWM count from the LUT 38. The retrieved value, in turn, determines the number of PWM clock counts that, in turn, govern the duration of a reflective portion 52 of a PWM cycle 50. The remaining counts form a non-reflective portion 54 (i.e., the remaining portion) of the PWM cycle 50. Stated differently, the PWM cycle 50 may be viewed as being formed from consecutive and non-overlapping time segments 51, each of which has the duration of a specified number of clock cycles. In some embodiments of the invention, the pixel cell, at the beginning of the PWM cycle 50, is in the non-reflective state. The number of PWM counts determine the number (if any) of time segments 51 from time T0 until time T1 (at the end of the reflective portion 52 of the PWM cycle 50) in which the pixel cell remains in the reflective state. At the conclusion (time T1) of the reflective portion 52, the pixel cell transitions to its non-reflective state (to begin the non-reflective portion 54) until the end of the PWM cycle 50 at time T2. The duration of the PWM cycle 50 depends on the configuration of the projection display system. For the single LC SLM panel-configuration of the projection display system 10 (FIG. 1), the PWM cycle time is equal to a multiple of one sixth of the field time interval ( 1/60 seconds). The multiple may be set as desired to mitigate color breakup, a visual artifact associated with temporal color sequential displays. PWM cycle times may be at 1/240 Hz, 1/360 Hz, and so on. Each pair of PWM cycles is dedicated to an illumination color primary (red or green or blue). One PWM cycle asserts a first voltage polarity and the second PWM cycle asserts the opposite voltage polarity while driving the pixel cell to establish the pixel intensity (such as the PWM cycle 50). More specifically, the second PWM cycle should assert the bright state for the same duty cycle duration as the first PWM cycle, except that the voltage field across the LC material is reversed in polarity. Additionally, the reflectivity state sequence in the second PWM cycle may proceed in the reverse time order of the driving PWM cycle. Using the retrieved value from the LUT 38, the processor 32, in accordance with some embodiments of the invention, utilizes the corresponding PWM count to time the duration of the PWM cycle for the respective pixel by means of the video data interface 31 (FIG. 3). Referring to FIG. 5, in some embodiments of the invention, the entries of the LUT 38 (FIG. 3) establish a relationship between the PWM counts and the received video data values (represented by “table index values” in FIG. 5). For example, the LUT 38 establishes, in conjunction with other features of the display projection system 10 described below, relationships between the video data values and the pixel intensities that appear in the projected image. However, the video data that is furnished to the projection display system 10 may not have a linear relationship to the pixel intensities that are required for the projected image because the video data may be pre-compensated to drive a non-linear cathode ray tube (CRT) display, for example. More specifically, the video data that is furnished to the projection display system 10 (FIG. 1) may be pre-compensated to accommodate the non-linear responses of phosphors of a CRT display. Thus, a conventional CRT display receives the pre-compensated video data and directly drives the CRT tube with this data. However, for a SLM display system, such as the projection display system 10, the pre-compensation must be removed from the video data. Therefore, the relationship between the video data and the PWM counts should not be linear, but rather, should be non-linear in a manner that removes the CRT pre-compensation and applies gamma compensation appropriate for the SLM in the projection system. The correct gamma compensation required will depend on the voltage to reflectance transfer characteristics of the SLM as well as the application. For office displays, it is common to drive to a final optical gamma of 2.2, while for home theater, it is more common to drive to a final optical gamma of 2.5. More specifically, still referring to FIG. 5, system 10 may establish a non-linear relationship between the video data that is furnished to the system 10 and the PWM clock counts. A curve 106, for example, represents the needed relationship imposed by the LUT 38 between the blue component video data and the blue SLM PWM count; a curve 104 represents the needed relationship between the green component video data and the green SLM PWM count; and a curve 102 represents the needed relationship between the red component video data and the red SLM PWM count. As can be seen from FIG. 5, for the darker video levels (i.e., the smaller table index values), the compensated PWM count increases at a slower rate than for the brighter pixel intensity values (i.e., the larger table index values). The PWM clock count resolution (and thus, the video grayscale resolution, as appears in the projected image), may be determined by the minimum PWM cycle clock duration is that required to form intensity changes that are small enough to be below the visual contouring threshold for the darkest tones. Because the PWM clock resolution also establishes the duration of the time segment 51 (see FIG. 4), the smaller the duration of the time size 51, the higher the frequency of the needed clock frequency. This may present challenges, in that a high clock frequency means a higher power consumption. Referring back to FIG. 3, the electrical system 30 further includes duty cycle altering components 35. These components enable the duty cycle to be selectively altered. In some embodiments of the present invention, it may be desirable to periodically reduce the duty cycle, particularly for darker relative to lighter pixels. This enables an increase in bit depth, in some embodiments, without requiring any kind of performance increase. Thus, a bit depth improvement may be achieved, in some embodiments, cost effectively. In one embodiment, the duty cycle may be altered from frame to frame, adding more gray control. For example, a duty cycle variation may be implemented from a 50% duty cycle, for example, on even frames to a 40% duty cycle on odd frames. However, in some embodiments, the lookup table 38 may be extended to contain a set of n values having a range 0 to n−1. Thus, small changes may be made to the duty cycle across different fields. For example, different ranges may be used for values in the table. In some embodiments, a positive range may be used that also includes zero. In the illustrated embodiment, the duty cycle may be selectively reduced by 0 to 10% and, specifically, 0, 2, 5, or 10%. Advantageously, the range may contain relatively small numbers to reduce the amount of frame to frame change that is introduced. For example, the maximum extent of the duty cycle variation may be maintained under 25% in some embodiments of the present invention. In some embodiments, additional values may be added to the mappings for a given pixel value in specific frames, allowing effective control of the modulation and improved bit density. However, it is also possible to use a subtraction or other arithmetic alteration schemes. Referring to FIG. 6, the components 35 may include a selector 60 controlled by a map function 62. The map function 62 receives a frame number for the frame to be currently displayed. The lookup table or LUT 38 includes the values for various pixels, only four of which are shown. The pixel value to map is received from the processor 32 in some embodiments. Thus, the pixel value to map points to a particular pixel value in the LUT 38 and also to a particular pixel data in the delta memory 38a. Thus, for the pixel 0, there are two values in this example. One being the pixel value 00, which indicates no change in the duty cycle and the pixel value 01, which indicates a reduction of the duty cycle by 10%. The selector 60, based on the map function 62, changes or does not change the duty cycle from the 50% duty cycle. Of course, the duty cycle for the base value (which is to be altered) may have values other than 50%. Generally, the delta is only applied at the lower intensity levels in particular frames. Thus, for example, the duty cycle may be reduced on odd frames for their lower intensity values. As one example, only the lower two intensity values may be subject to duty cycle alteration. Returning to the example shown in FIG. 6, after looking up the values in the lookup table 38 and the delta table 38a, if the pixel value is 1, the LUT 38 returns the pixel value 1 line while the delta table 38a returns the pixel value 10 or 11 entries. The selector 60 then uses the map function 62 to select one of the two delta table entries. In this case, pixel value 10 or 11 is to be added to the LUT entry to arrive at the final duty cycle mapping. The map function 62 may implement any of a variety of different functions. The simplest function is a modulo function that simply does a mod n on the frame number. Applied to this example, the map function 62 (implementing mod n) returns 0 for even frames and 1 for odd frames, to select either the 1 or 0 entries in the delta table 38a. Then, referring to FIG. 7, in the simple mod n example, the delta table 38a may have variations from 0 to 10%, including intermediate levels of 2% and 5%. The duty cycle percentages are indicated instead of the raw counts for simplicity of illustration. The left side of FIG. 7 illustrates the PWM waveform that the hardware would produce for pixel value 1 on even and odd frames using the modulo mapping functions as the map function 62. Thus, the even frames with pixel values of 1 have a 50% duty cycle, while odd frames with the same pixel value have a 40% duty cycle. The modulo function may introduce artifacts because the given delta is always added at a periodic rate. This may introduce flicker other undesirable artifacts. To reduce these artifacts, a more complex function may be used. In one embodiment, the order in which to apply the n delta entries every n frame is randomly altered. In this way, an entry 0 does not always occur at the same point in a group of n frames. Then, the map function 62 can be built with a small pseudo-random generator (not shown) that randomizes a rename table to index into the delta entries. The rename table maps frame numbers onto delta entries. While the invention has been disclosed with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of the invention. | <SOH> BACKGROUND <EOH>This invention relates generally to microdisplays. A projection display system typically includes one or more spatial light modulators (SLMs) that modulate light for purposes of producing a projected image. The SLM may include, for example, a liquid crystal display (LCD) such as a high temperature polysilicon (HTPS) LCD panel or a liquid crystal on silicon (LCOS) microdisplay, a grating light valve or a MEMs (where “MEMs” stands for micro-electro-mechanical devices) light modulator such as a digital mirror display (DMD) to modulate light that originates from a lamp of the projection display system. In typical projection display systems, the lamp output is formatted with optics to deliver a uniform illumination level on the surface of the SLM. The SLM forms a pictorial image by modulating the illumination into spatially distinct tones ranging from dark to bright based on supplied video data. Additional optics then relay and magnify the modulated illumination pattern onto a screen for viewing. The SLM typically includes an array of pixel cells, each of which is electrically controllable to establish the intensity of a pixel of the projected image. In some projection display systems, SLMs are transmissive and in others, they are reflective. For the purposes of simplification, the discussion will address reflective SLMs. An SLM may be operated so that each pixel has only two states: a default reflective state which causes either a bright or a dark projected pixel and a non-default reflective state which causes the opposite projected pixel intensity. In the case of an LCOS SLM, the pre-alignment orientation of the LC material and any retarders in the system determine whether the default reflective state is normally bright or normally dark. For the purposes of simplification, the discussion will denote the default reflective state as normally bright, i.e., one in which the pixel cell reflects incident light into the projection lens (the light that forms the projected image) to form a corresponding bright pixel of the projected image. Thus, in its basic operation, the pixel cell may be digitally-controlled to form either a dark pixel (in its non-default reflective state) or a bright pixel (in its default reflective state). In the case of a DLP SLM, the states may represent the pixel in a co-planar position to the underlying substrate. Although its pixels are operated digitally, the above-described SLM may also be used in an application to produce visually perceived pixel intensities (called “gray scale intensities”) between the dark and bright levels. For such an application, each pixel may be controlled by pulse width modulation (PWM), a control scheme that causes the human eye to perceive gray scale intensities in the projected image, although each pixel cell still only assumes one of two states at any one time. The human visual system perceives a temporal average of pixel intensity when the PWM control operates at sufficiently fast rates. In the PWM control scheme, a pixel intensity (or tone) is established by controlling the time that the pixel cell stays in its reflective state and the time that the pixel cell remains in the non-reflective state during an interval time called a PWM cycle. This type of control is also referred to as duty cycle control in that the duty cycle (the ratio of the time that the pixel cell is in its reflective state to the total time the pixel cell is in its non-reflective and reflective states) of each PWM cycle is controlled to set the pixel intensity. A relatively bright pixel intensity is created by having the pixel cell spend a predominant proportion of time in its reflective state during the PWM cycle, while a relatively dark pixel intensity is created by having the pixel cell spend a predominant amount of time in its non-reflective state during the PWM cycle. The quality of the projected image typically is a function of the number of possible gray scale intensities, also called the “bit depth.” For the above-described PWM control scheme, a bit depth of “N” means that the PWM cycle is divided into 2 N time consecutive and non-overlapping time segments. For a particular PWM cycle, each of the time segments in which the pixel cell is in its reflective state contributes to the overall luminance of the corresponding pixel. Each time segment of the PWM cycle typically corresponds in duration to the cycle of a clock signal. Thus, the larger the number of time segments (i.e., the greater the number of gray scale intensities), the higher the frequency of this clock signal, thereby requiring a high speed clock to form the pixel gray scale or tonal range. Power consumption is also a function of this clock frequency and also increases with bit depth. Other factors may increase the clock rate needed for a particular bit depth. For example, for a three SLM LCD panel projection system (one SLM for each primary color), the PWM cycle may have a period that is equal to one half of the video data's field time (typically 1/60 second). Opposite drive voltage polarities are needed in LCD systems to prevent voltage bias accumulation. This is well known for liquid crystal display systems. Thus, LCD SLM devices require two PWM cycles in each video data field. This doubles the clock rate requirement. For a two SLM panel projection system where one of the SLM panels is temporally shared by two primary colors, the video frame time must be split to allocate PWM cycles to each primary color, thereby increasing the needed PWM clock rate if the same bit depth is maintained in all colors. For a one SLM panel projection system with an SLM panel temporally shared by all three primary colors, the video frame time must be further subdivided. For an LCOS SLM the video frame time would be divided into six PWM cycles, a pair for each primary color. The PWM clock period may have an even shorter duration when the unequal length PWM cycles are needed to adjust the display white point. Since common projection lamps are rich in blue and weak in red output, it is generally necessary to devote longer portions of the video frame time to red to achieve white balance. This necessitates the PWM clock period to be increasingly small and the clock frequently and power consumption to be increasingly high. Thus, there is a need for modulation techniques that improve bit depth of microdisplays. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>FIG. 1 is a schematic diagram of a projection display system according to an embodiment of the invention; FIG. 2 is a view of a light impinging face of a color filter wheel; FIG. 3 is a block diagram of an electrical system of the projection display system according to an embodiment of the invention; FIG. 4 is an illustration of a pulse width modulation control technique for a pixel cell according to an embodiment of the invention; FIG. 5 depicts relationships between pixel intensities and a table index value; FIG. 6 is a schematic depiction of the duty cycle modulating scheme in accordance with one embodiment of the present invention; and FIG. 7 is a timing diagram showing the duty cycle for a pixel and an altered duty cycle for the pixel in a different frame. detailed-description description="Detailed Description" end="lead"? | 20050119 | 20150714 | 20060720 | 99476.0 | G09G510 | 0 | ABDULSELAM, ABBAS I | ILLUMINATION MODULATION TECHNIQUE FOR MICRODISPLAYS | UNDISCOUNTED | 0 | ACCEPTED | G09G | 2,005 |
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11,038,375 | ACCEPTED | Personal table | A personal table is provided having a table top supported by a support assembly. The table top is preferably constructed from blow-molded plastic and the support assembly preferably includes a first leg and a second leg that are pivotally connected. The legs desirably have a generally X-shaped configuration when the legs are placed in an upright position and the legs can be collapsed into a storage position. Each of the legs may include a lower portion, a body portion and an upper portion that is preferably selectively connected to the table top. The legs, for example, can be connected to the table top by inserting the upper portions of the legs into leg receiving recess formed in the table top. The leg receiving recesses are preferably integrally formed in the bottom surface of the table top as part of a one-piece construction. Desirably, a plurality of leg receiving recesses are formed in the bottom surface of the table top and the legs can be selectively attached to the leg receiving recesses in order to vary the height of the table. | 1. A personal table that is intended to be used by a single user, the personal table comprising: a table top constructed from blow-molded plastic, the table top including an upper portion, a lower portion and a hollow interior portion formed during the blow-molding process; and a single support assembly that is sized and configured to support the table top above a surface, the single support assembly being capable of moving between an extended position and a collapsed position, the single support assembly including only two leg support portions, the single support assembly comprising: a first leg support portion including an upper section and a body section; and a second leg support portion including an upper section and a body section, the first leg support portion and the second leg support portion being pivotally connected, the first leg support portion and the second leg support portion having a generally X-shaped configuration in the extended position; wherein at least one leg support portion is selectively connected in more than one fixed position relative to the table top to allow the height of the table to be adjusted when the single support assembly is in the extended position; and wherein at least one leg support portion is selectively connected to the table top to allow the single support assembly to be moved between the extended and collapsed positions. 2. The personal table as in claim 1, further comprising at least one leg receiving portion formed in the table top as part of a unitary, one-piece structure, the leg receiving portion being sized and configured to receive at least a portion of an upper section of a leg support portion. 3. The personal table as in claim 1, further comprising a receiving channel formed in a lower portion of the table top, the receiving channel being sized and configured to receive at least a portion of a body section of a leg support portion of the single support assembly when the single support assembly is in the collapsed position. 4. The personal table as in claim 1, further comprising a lip that extends generally downwardly from the table top, the lip being formed as part of a unitary, one-piece structure with the table top; and further comprising an opening in the lip that is sized and configured to receive a portion of a body section of a leg support portion of the single support assembly when the single support assembly is in the collapsed position. 5. The personal table as in claim 1, further comprising an opening in a sidewall of the table top that is sized and configured to receive at least a portion of the body section of a leg support portion of the single support assembly when the single support assembly is in the collapsed position. 6. The personal table as in claim 1, further comprising at least three leg receiving portions formed in the table top as part of a unitary, one-piece structure, wherein the upper section of a leg support portion can be selectively removed from one of the at least three leg receiving portions and received within another of the at least three leg receiving portions to allow a height of the personal table to be adjusted. 7. The personal table as in claim 1, wherein the body section of the first leg support portion includes at least two elongated members and the body portion of the second leg support portion includes at least two elongated members. 8. The personal table as in claim 1, wherein the first leg support portion is permanently connected to the table top and the second leg support portion is selectively connected to the table top. 9. The personal table as in claim 1, further comprising a height adjustment mechanism for selectively increasing or decreasing a distance between the upper section of the first leg support portion and the upper section of the second leg support portion in order to increase or decrease the height of the personal table. 10. A personal table that is intended to be used by a single user and has a height that is adjustable, the personal table comprising: a table top constructed from blow-molded plastic, the table top including an upper portion, a lower portion and a hollow interior portion formed during the blow-molding process; at least one leg receiving portion integrally formed in the table top as part of a unitary one-piece construction; and a single support assembly that is sized and configured to allow the height of the table to be adjusted, the single support assembly including a single pair of leg support portions with a first leg support portion and a second leg support portion that are pivotally connected, the first leg support portion including an upper section and a body section, the second leg support portion including an upper section and a body section, the first leg support portion and the second leg support portion being movable between a first position in which the first leg and the second leg have a generally X-shaped configuration and a second position in which the first leg and the second leg are in a collapsed configuration. 11. The personal table as in claim 10, further comprising at least two leg receiving portions integrally formed in the table top as part of a unitary one-piece construction, the upper section of the first leg support portion being sized and configured to be selectively received and retained within one of the leg receiving portions, the upper section of the second leg support portion being sized and configured to be selectively received and retained within another of the leg receiving portions. 12. The personal table as in claim 11, wherein the first leg support portion can be selectively removed from one of the leg receiving portions and received within another of the leg receiving portions to allow the height of the personal table to be adjusted. 13. The personal table as in claim 10, further comprising at least one retaining member positioned adjacent to each of the at least one leg receiving portions, the retaining member being integrally formed in the table top as part of the unitary one-piece construction, the retaining member being sized and configured to retain a leg support portion within a leg receiving portion. 14. The personal table as in claim 10, wherein the first leg support portion is permanently connected to the table top and the second leg support portion is selectively connected to the table top. 15. The personal table as in claim 10, wherein the body section of the first leg support portion includes at least two elongated members and the body portion of the second leg support portion includes at least two elongated members. 16. A personal table that is sized and configured to be used by a single person and the table being adjustable in height, the personal table comprising: a blow-molded plastic table top including an upper portion, a lower portion and a hollow interior portion formed during the blow-molding process; a single support assembly that is at least partially selectively connected to the table top, the single support assembly being selectively movable between an extended position and a collapsed position, the single support assembly including a single pair of leg support portions that are pivotally connected, the single pair of leg support portions having a generally X-shaped configuration when the single support assembly is in the extended position; the single pair of leg support portions being generally positioned adjacent to each other in the collapsed position; and a plurality of leg receiving portions integrally formed in the table top as part of a unitary, one-piece structure, the leg receiving portions being sized and configured to interchangeably receive and retain a portion of the single support assembly in a generally fixed position relative to the table top to allow the height of the personal table to be adjusted. 17. The personal table as in claim 16, further comprising an opening in a side wall of the table top, the opening being sized and configured to allow at least a portion of the single leg support assembly to extend through the opening when the legs are in the collapsed position. 18. The personal table as in claim 17, wherein the opening is sized and configured to receive and retain the legs in a snap fit configuration when the legs are in the collapsed position. 19. The personal table as in claim 16, wherein each of the leg support portions include an elongated upper attachment portion that is sized and configured to be received and retained within the leg receiving portions. 20. The personal table as in claim 16, wherein each of the leg support portions includes an elongated body and each elongated body includes at least two elongated members. 21. A personal table that is intended to be used by a single user, the personal table comprising: a table top constructed from plastic, the table top including an upper portion, a lower portion and a sidewall; a single support assembly that is sized and configured to support the table top above a surface, the single support assembly being capable of moving between an extended position and a collapsed position, the single support assembly including only two leg support portions, the single support assembly comprising: a first leg support portion including an upper section and a body section; and a second leg support portion including an upper section and a body section, the first leg support portion and the second leg support portion being pivotally connected, the first leg support portion and the second leg support portion having a generally X-shaped configuration in the extended position; wherein at least one leg support portion is selectively connected in more than one fixed position relative to the table top to allow the height of the table to be adjusted when the single support assembly is in the extended position; and wherein at least one leg support portion is selectively connected to the table top to allow the single support assembly to be moved between the extended and collapsed positions; and an opening in the sidewall of the table top that is sized and configured to receive at least a portion of the body section of a leg support portion of the single support assembly when the single support assembly is in the collapsed position. 22. The personal table as in claim 21, further comprising at least one leg receiving portion formed in the table top as part of a unitary, one-piece structure, the leg receiving portion being sized and configured to receive at least a portion of an upper section of a leg support portion. 23. The personal table as in claim 21, further comprising a receiving channel formed in a lower portion of the table top, the receiving channel being sized and configured to receive at least a portion of a body section of a leg support portion of the single support assembly when the single support assembly is in the collapsed position. 24. The personal table as in claim 21, further comprising at least three leg receiving portions formed in the table top as part of a unitary, one-piece structure, wherein the upper section of a leg support portion can be selectively removed from one of the at least three leg receiving portions and received within another of the at least three leg receiving portions to allow a height of the personal table to be adjusted. 25. The personal table as in claim 21, wherein the body section of the first leg support portion includes at least two elongated members and the body portion of the second leg support portion includes at least two elongated members. 26. The personal table as in claim 21, wherein the first leg support portion is permanently connected to the table top and the second leg support portion is selectively connected to the table top. 27. The personal table as in claim 21, further comprising a height adjustment mechanism for selectively increasing or decreasing a distance between the upper section of the first leg support portion and the upper section of the second leg support portion in order to increase or decrease the height of the personal table. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of pending U.S. patent application Ser. No. 10/340,018, filed Jan. 9, 2003, entitled PERSONAL TABLE. U.S. patent application Ser. No. 10/340,018 claims priority to and the benefit of U.S. provisional patent application Ser. No. 60/347,556, filed Jan. 9, 2002, entitled PERSONAL TABLE; U.S. provisional patent application Ser. No. 60/364,712, filed Mar. 14, 2002, entitled PERSONAL TABLE; and U.S. provisional patent application Ser. No. 60/421,221, filed Oct. 25, 2002, entitled PERSONAL TABLE. In addition, U.S. patent application Ser. No. 10/340,018 is a continuation-in-part of U.S. design patent application Ser. No. 29/167,624, filed Sep. 18, 2002, entitled TABLE LEG, now U.S. Pat. No. D469,994; U.S. patent application Ser. No. 10/340,018 is also a continuation-in-part of U.S. design patent application Ser. No. 29/167,628, filed Sep. 18, 2002, entitled TABLE TOP, now U.S. Pat. No. D469,996; and U.S. patent application Ser. No. 10/340,018 is a continuation-in-part of U.S. design patent application Ser. No. 29/167,611, filed Sep. 18, 2002, entitled TABLE TOP, now U.S. Pat. No. D470,352. Each of these patents and applications are expressly incorporated herein by reference in their entireties. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to tables and, in particular, to a light-weight table that may be adjustable in height and may have legs that can be collapsed into a storage position. 2. Description of Related Art Conventional tables are used for a variety of purposes and come in a wide array of designs. In some situations, it is desirable to have a smaller table for personal or individual use. For example, persons living in a small space, such as a studio apartment, may choose to use a smaller personal-sized table on which to dine or perform other tasks. Other persons may use a personal table to place beside a chair for the convenience of holding objects while reading, watching television or listening to the radio. Still others may use personal tables to perform tasks such as writing, working, or using a computer. Conventional tables often include table tops constructed from wood, particle board or metal. Table tops constructed from wood, particle board or metal, however, are often relatively heavy and this may make the table awkward or difficult to move. Conventional table tops constructed from wood or metal are also relatively expensive and the table tops must generally be treated or finished before use. For example, table tops constructed from wood must generally be sanded and painted, and metal table tops must be formed into the desired shape and painted. In addition, these relatively heavy table tops increase the cost of transportation, shipping, and storage of the tables. In order to decrease the weight of conventional tables, table tops can be constructed from relatively thin, light-weight materials. Disadvantageously, these light-weight table tops frequently require reinforcing members or other structural parts such as frames, railings, brackets and the like to strengthen the table top. These additional parts may increase the strength of the table top, but these additional parts also increase the weight of the table. In addition, these additional parts increase manufacturing costs and require additional time to assemble the table. Furthermore, these additional parts may have sharp edges that can injure the user's legs, arms or other body parts. Known tables may also allow the height of the table to be adjusted to suit the needs of the user. For example, the length of the table legs may be increased or decreased by a telescoping assembly. Disadvantageously, because the telescoping assemblies include overlapping components, the assembly is relatively heavy. Additionally, conventional tables may use other mechanisms to allow the height of the table to be adjusted, but these devices are often relatively complex and require additional parts, which increases the costs to manufacture and assemble the table. These complex designs may also result in tables that are relatively difficult to use. Another type of known table is a traditional card table in which each leg is pivotally connected to the table top by a brace and each leg individually folds against the table top. Known tables may attempt to reduce the inconvenience of individually folding legs against the table top by coupling two of the legs together by a long connecting rod. This may increase the stability of the table top and enable the user to simultaneously fold two legs into the collapsed position. The connecting rods, however, increase the cost of the table, reduce space under the table top, and may easily break or become disconnected. Conventional tables may also detachably connect the legs to the table top to allow the user to more easily collapse, move and store the table. Disadvantageously, the detachable legs often create a table that is not sturdy or stable. Additionally, moving a table with this type of attachment when the legs are still attached is often difficult because the legs may undesirably detach. These known types of table may include an attachment that mechanically secures the leg to the table top. These mechanical attachments, such as plastic or metal clips or brackets, often break or are otherwise damaged. Further, attachment of these devices to the table top may structurally weaken the table top, which may allow the table to unexpectedly fail. Further, attaching the four separate attachment mechanisms to the table top by fasteners such as screws or bolts may undesirably weaken the table top. Many conventional tables include four legs in order to support the table top above a surface such as the floor. The four separate legs, however, increase the weight of the table. In additional, the four legs require four separate attachment mechanisms to attach the legs to the table top, which increases the cost and complexity of the table. BRIEF SUMMARY OF THE INVENTION A need exists for a table that eliminates the above-described disadvantages and problems. One aspect of the present invention is a relatively small-sized table that is designed for use by a single person. This type of table that is intended for use by an individual is referred to as a personal table, but it will be appreciated that more than one person could use the table if desired. Advantageously, the personal table is relatively small and light-weight, which makes the table easy to move and transport. Significantly, because the table is sized and configured for personal use, it does not take up unnecessary space or provide a large amount of unused space. Therefore, the personal table provides ample space for a single user without requiring a large area or wasting unnecessary space. Another aspect of the personal table is it can be used for a wide variety of different situations and uses such as a table for supporting a television, computer, sewing machine, microwave, lamp, luggage, and the like. The table can also be used for a wide variety of other uses such as a bedside table, coffee table, night stand, desk, shop table, and the like. Further, the table can be used while performing a wide variety of tasks such as reading, writing, studying, working, etc. Thus, the personal table can be used in a number of different environments and it can perform numerous different tasks. Yet another aspect of the personal table is the height of the table can be readily adjusted. Advantageously, the adjustable height table allows it to be used for many different purposes, such as those discussed above. A further aspect of the personal table is the table top is support by a single pair of legs. The legs are preferably pivotally connected and the legs preferably allow the height of the table top to be easily adjusted. Significantly, because the table top is support by a single pair of legs, that provides additional leg room and/or storage room under the table. In addition, the single pair of legs is light-weight and easily attached to the table top. The single pair of legs can desirably support the table top and suitable objects placed on the personal table. Advantageously, because the personal table has a relatively small size, the single pair of legs can properly support the table. A still further aspect of the personal table is the legs are preferably movable between a use position and a storage position. The legs preferably extend outwardly from the table top in the use position and the legs support the table top above a surface such as the floor. In the storage position, the legs are preferably collapsed into a relatively compact area, which allows the table to be easily transported or stored. The legs, for example, may be placed adjacent and/or proximate to the bottom surface of the table top in the collapsed position. Another aspect of the personal table is the table top is preferably constructed from a lightweight material so that the table is easily portable and can be readily lifted and moved by a single person. Desirably, the table top is constructed from blow-molded plastic, such as high density polyethylene. The blow-molded plastic table top provides a rigid, high-strength structure that is capable of withstanding repeated use and wear. Advantageously, the blow-molded table top can be easily manufactured and formed into the desired size and shape. In addition, the blow-molded table top can form a structural component of the table to minimize the number of components and size of the table. Thus, frames, braces or other support members are not required to support the table top. Yet another aspect of the personal table is the legs can be attached to recesses and/or grooves formed in the table top. In particular, the legs are preferably attached to the table top by a snap, interference or friction fit. This connection of the legs to the table top may also allow the legs to be selectively removed or detached from the table top. Advantageously, because the legs do not require any fasteners or other structures to be connected to the table top, no stress points or other types of weakness are formed in the table top. Thus, the strength and rigidity of the table top is not decreased by forming holes or inserting fasteners into the table top. The legs may also be pivotally or slidably attached to the table top. One aspect of the personal table is both legs may be removably attached to the table top. This allows the legs to be easily removed for transportation and/or storage. In addition, the removal of both legs may allow the height of the table to be easily adjusted by attaching the legs to different grooves or recess in the table top. One of the legs, however, may be permanently or more securely attached to the table top, and the other leg may be more easily attached or detached from the table top. Thus, the selectively detachable leg may be detached from the table top when the height of the a table is desired to be adjusted and/or the table is desired to be moved or stored. Of course, both of the legs may be easily detached from the table top, but only one of the legs may be detached to allow, for example, the height of the table to be adjusted or to move the legs into a collapsed position. A further aspect of the personal table is the pair of legs are preferably pivotally connected by a pin, bolt or screw into a generally X-shaped configuration. The pivotal connection advantageously allows the legs to be quickly moved between the storage and use positions. The pivotal connection also allows the height of the table to be readily adjusted. Desirably, each leg includes a lower portion that contacts a support surface such as the floor, a body portion, and an upper portion that is sized and configured to be connected to the table top. The body portion of each of the legs may include two support members, which helps prevent twisting or undesirable torque on the connection of the upper and lower portions to the elongated body portion. Another aspect of the personal table is the legs can be attached to the table top via double hinge members. Advantageously, the legs can be pivotally attached by the double hinge members to the table top to allow the height of the table top to be adjusted. In particular, the double hinge members are preferably movable between different positions and that allows the height of the table top to be changed. The legs can also be slidably attached to the table top and a ratchet assembly may be used to selectively adjust the height of the table top. A further aspect of the personal table is the legs are preferably offset towards one side of the table top. Advantageously, because the legs are not placed in the center of the table, that provides enhanced legroom for the user. This also allows the table top to be positioned closer to the body of the user, which may be more convenient for the user. Advantageously, the personal table is relatively simple to manufacture because it preferably consists of a table top constructed from blow-molded plastic and a pair of pivotally interconnected legs. The blow-molded table top includes two opposing walls that are spaced apart, which increase the strength and rigidity of the table top. The blow-molded table top may also include one or more depressions or tack-offs to further increase the strength of the table top and/or interconnect the spaced apart walls. Significantly, a blow-molded table top is light-weight, durable, generally weather resistant and temperature insensitive, and it does not corrode, rust or otherwise deteriorate. The blow-molded table top can also be formed in various shapes, sizes, configurations and designs. Additionally, the personal table is easy to assemble, which reduces manufacturing and labor costs. Further, the consumer can easily assemble the personal table and the consumer will appreciate many of the aspects of the personal table such as the light-weight, easy height adjustment, portability, sturdiness, and wide variety of uses in any different environments. These and other aspects, features and advantages of the present invention will become more fully apparent from the following detailed description of preferred embodiments and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The appended drawings contain figures of preferred embodiments to further clarify the above and other aspects, advantages and features of the present invention. It will be appreciated that these drawings depict only preferred embodiments of the invention and are not intended to limits its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: FIG. 1 is a front perspective view of a personal table in accordance with a preferred embodiment of the present invention; FIG. 2 is a rear perspective view of the personal table shown in FIG. 1; FIG. 3 is a front perspective view of a portion of the personal table shown in FIG. 1, illustrating the support legs in an extended position; FIG. 4 is a front view of the support legs shown in FIG. 3, illustrating the legs in an extended position and a collapsed position; FIG. 5 is a top view of the support legs shown in FIG. 3; FIG. 6 is a right side view of the support legs shown in FIG. 3; FIG. 7 is a front perspective view of a personal table in accordance with another preferred embodiment of the present invention, illustrating the body portion of the support legs with a single support member; FIG. 8 is a rear perspective view of a personal table in accordance with yet another preferred embodiment of the present invention; FIG. 9 is a rear perspective view of the personal table shown in FIG. 8, illustrating the support legs in a reversed position; FIG. 10 is a top view of a potion of the personal table shown in FIG. 1, illustrating the table top; FIG. 11 is a front view of the portion of the personal table shown in FIG. 10; FIG. 12 is a rear view of the portion of the personal table shown in FIG. 10; FIG. 13 is a bottom perspective view of the portion of the personal table shown in FIG. 10; FIG. 14 is right side view of the portion of the personal table shown in FIG. 10; FIG. 15 is a left side view of the portion of the personal table shown in FIG. 10; FIG. 16 is a bottom perspective view of a portion of a personal table in accordance with still another preferred embodiment of the present invention; FIG. 17 is a bottom perspective view of the personal table shown in FIG. 16, illustrating the support legs attached to the bottom surface of the table top and in an extended position; FIG. 18 is a bottom perspective view of the personal table shown in FIG. 16, illustrating the support legs attached to the bottom surface of the table top and in a collapsed position; FIG. 19 is a bottom perspective view of a personal table in accordance with another preferred embodiment of the present invention; FIG. 20 is a bottom perspective view of a personal table in accordance with yet another preferred embodiment of the present invention, illustrating the support legs in a collapsed position; FIG. 21 is an enlarged bottom perspective view of a portion of the personal table shown in FIG. 20; FIG. 22 is a bottom perspective view of a portion of a personal table in accordance with still another preferred embodiment of the present invention; FIG. 23 is a partial schematic side view of a portion of the personal table shown in FIG. 22; FIG. 24 is a partial schematic side view of a portion of the personal table shown in FIG. 22; FIG. 25 is a partial schematic side view of a portion of the personal table shown in FIG. 22; FIG. 26 is a partial schematic side view of a portion of the personal table shown in FIG. 22; FIG. 27 is a bottom view of a personal table in accordance with yet another preferred embodiment of the present invention, illustrating a ratchet assembly in a first position; and FIG. 28 is a bottom view of the personal table shown in FIG. 27, illustrating the ratchet assembly in a second position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is directed towards a table and, in particular, to a table that is intended to be used by a single user at one time. The principles of the present invention, however, are not limited to a table intended for use by an individual user. It will be understood that, in light of the present disclosure, the table can be used by more than one user at any given time. Additionally, to assist in the description of the table, words such as top, bottom, front, rear, right and left are used to describe the accompanying figures. It will be appreciated, however, that the table can be located in a variety of desired positions—including various angles, sideways and even upside down. A detailed description of the table now follows. As seen in FIG. 1, an exemplary table 10 is shown. The table 10 is preferably a relatively small-sized table that is intended for use by a single person at one time. Advantageously, because the table 10 is sized and configured for personal use, it does not require a large amount of space. Therefore, the table 10 provides ample space for a single user without requiring a large area or unnecessary space. This table 10 that is sized and configured for use by a single person is referred to as a personal table. The personal table 10 includes a table top 12 and a support assembly 14 that is used to support the table top above a surface such as the floor or ground. The table top 12 includes a top surface 16, a bottom surface 18, a front side 20, a rear side 22, a right side 24 and a left side 26. The table top 12 may also include a beveled, sloped or rounded surface 28 disposed between the top surface 16 and one or more of the sides 20, 22, 24 and 26. The beveled surface 28 may increase the comfort and safety of the user. The beveled surface 28, for example, may be larger along the front surface 20 of the table top 12, but it will be appreciated that the personal table 10 does not require a beveled surface. As shown in FIG. 1, the table top 12 preferably has a generally rectangular configuration with rounded comers and slightly rounded outer edges or sides 20, 22, 24, and 26. Desirably, the table top 12 is about thirty (30) inches in length and about twenty (20) inches in width, but one skilled in the art will appreciate that the table top can have other suitable sizes and configurations. For example, the table top 12 may be larger or smaller and the table top can have other configurations such as square, circular, oval, and the like depending, for example, upon the intended use of the personal table 10. In addition, the corners and edges of the table top 12 do not have to rounded and, in contrast, the corners and edges could have any desirable configuration, but the rounded features may increase the comfort and/or safety of the user. Advantageously, the personal table 10 can be used for a wide variety of purposes and in a number of different environments. For instance, the personal table 10 can be used as a television stand, computer table, sewing table, bedside table, coffee table, microwave stand, desk, shop table, luggage stand and the like. In addition, the personal table 10 can be used for working, reading, writing and other suitable uses. Accordingly, the personal table 10 is capable of many different uses and it is preferably sized and configured to be used by a single person at one time. The personal table 10, as discussed in more detail below, is preferably sized and configured to support one or more objects related to these different tasks and uses. For example, the personal table 10 is desirably configured to support a television, computer, books, or luggage according to its intended use by the individual user. The table top 12 is preferably constructed from a lightweight material and, more preferably, the table top is constructed from plastic, such as high density polyethylene. The plastic table top 12 is desirably formed by a blow-molding process because, for example, it allows a strong, lightweight, rigid and sturdy table top to be quickly and easily manufactured. Advantageously, the blow-molded plastic table top 12 is lighter weight that conventional table tops constructed from wood or metal, and the blow-molded plastic table top can be constructed from less plastic, which saves manufacturing costs and reduces consumer costs. In particular, the blow-molded table top 12 can be manufactured with thin plastic walls and that allows the table top to cool faster during the manufacturing process, which decreases the manufacturing time. Further, the blow-molded plastic table top 12 can be constructed with any suitable configuration, shape, size, design and/or color depending, for example, upon the intended use of the personal table 10. For example, the table top 12 can be constructed with a generally rectangular configuration of about eighteen by about twenty-four inches (18×24), a table top with a generally circular configuration with a diameter of about twenty inches (20) or a table top with a generally square configuration with twenty-four inch (24) sides may be easily formed during the blow-molding process. Of course, it will be appreciated that the blow-molded table top 12 can have any suitable size and configuration depending, for example, upon the intended use of the personal table 10. The table top 12 is preferably constructed from blow-molded plastic because blow-molded plastic table tops are durable, weather resistant, generally temperature insensitive, corrosion resistant, rust resistant, and generally do not deteriorate over time. One skilled in the art, however, will appreciate that the table top 12 does not have to be constructed from blow-molded plastic and other suitable materials and/or processes can be used to construct the table top depending, for example, upon the intended use of the personal table 10. As shown in FIG. 1, the top surface 16 and the bottom surface 18 of the table top 12 are spaced apart a given distance and these two spaced apart surfaces help create a rigid and strong table top 12. Additionally, as described in more detail below, the top and bottom surfaces 16, 18 may be interconnected by one or more depressions or other reinforcement structures and these structures may be sized and configured to further increase the strength and rigidity of the table top 12. Advantageously, these depressions and/or other reinforcement structures can be integrally formed as part of a one-piece structure during the blow-molding process. The support assembly 14 is used to support the table top 12 above a surface such as the ground or floor. As shown in FIGS. 1-6, an exemplary embodiment of the support assembly 14 includes a first leg 30a and a second leg 30b. The first leg 30a and the second leg 30b preferably each include a lower portion 32a, 32b that is sized and configured to contact the ground or floor, a body portion 34a, 34b, and an upper portion 36a, 36b, respectively. The lower portion 32a, 32b of each of the legs 30a, 30b is preferably sized and configured to contact the ground or floor. Desirably, the lower portion 32a, 32b is an elongated member that has a length slightly less than the width of the table top 12 to provide a relatively stable base, but the elongated member could be longer or shorter. As shown in the accompanying figures, the lower portions 32a, 32b are preferably hollow tubes that are lightweight and easy to manufacture, and the tubes are preferably constructed from metal but any suitable materials may be used. End caps 42 may be attached to the ends of the lower portions 32a, 32b to prevent foreign objects from entering the hollow tubes and the end caps may provide a non-skid and non-marking surface. It will be understood, however, that neither the lower portions 32a, 32b or end caps 42 are required. As shown in FIGS. 1-6, the lower portions 32a, 32b are preferably positioned generally parallel to each other to provide a stable base for the personal table 10 that is resistant to tipping. It will be appreciated, however, that the lower portions 32a, 32b could have any desirable size, configuration or design depending, for example, upon the intended use of the personal table 10. For example, the lower portions 32a, 32b could have a triangular, square, rectangle, generally planar or other suitable configuration, and the support members could have any suitable width and length depending, for example, upon the intended use of the table 10. The body portions 34a, 34b of the legs 30a, 30b preferably consist of one or more elongated members that are used to support the table top 12 above a surface such as the ground or floor. It will be appreciated that the lengths of the body portions 34a, 34b of the legs 30a, 30b are preferably the same so that the table top 12 is supported in a generally horizontal position relative to the support surface and the length of the body portions may help determine the overall height of the table 10. The body portions 34a, 34b of each leg 30a, 30b are preferably constructed from generally hollow members, such as hollow metal tubes, which are lightweight and easy to manufacture, but the body portions may have any desired sizes and/or configurations. The ends of the body portions 34a, 34b are preferably securely connected to the lower portions 32a, 32b of the legs 30a, 30b by welding or other suitable means. As shown in FIGS. 1-6, the body portions 34a, 34b of the legs 30a, 30b may include two separate elongated support members 40a, 40b. Alternatively, as shown in FIG. 7, for example, the body portions 34a, 34b may include only a single elongated support member 40a, 40b. Advantageously, the body portions 34a, 34b constructed with two separate elongated support members 40a, 40b may help prevent twisting or torque on the connection of the body portions 34a, 34b to the lower portions 32a, 32b. Additionally, the two separate elongated support members 40a, 40b of the body portions 34a, 34b may be curved or spaced apart. In particular, the upper and lower portions of the body portions 34a, 34b may be spaced apart to facilitate connection of the body portions to the lower portion 32a, 32b, which may create a more secure connection. As best seen in FIGS. 5 and 6, the upper and lower portions of the body portions 34a, 34b are preferably curved outwardly and away from each other. The middle portions of the body portions 34a, 34b are preferably curved or arched towards each other to allow the body portions to be connected. Desirably, the body portions 34a, 34b are pivotally connected to allow the legs 30a, 30b to move relative to each other. The legs 30a, 30b are connected at a connection point by a connector such as a bolt, pin, screw or other type of suitable fastener 44. Desirably, the legs are curved together towards the connection point to decrease the length of the fastener 44 and the connection point is disposed closer to the table top 12 than the lower portions 32a, 32b of the legs 30a, 30b, but the legs may be connected at any desired point. It will be appreciated that the legs 30a, 30b may also be slidably or otherwise movably attached. As seen in FIGS. 3-6, for example, the upper portions 36a, 36b are attached to the upper portions of the body portions 34a, 34b. The upper portions 36a, 36b preferably have generally the same size and size, and the upper portions are desirably constructed from hollow metal tubes. The hollow tubes preferably have a generally circular configuration, but the tubes may also be oval, oblong, square, rectangular or have other suitable configurations. The upper portions 36a, 36b, however, do not have to be constructed from hollow metal tubes and the upper portions may also be constructed from other suitable components and materials. As best seen in FIGS. 3-5, the upper portions 36a, 36b are preferably spaced closer together than the lower portions 32a, 32b when the legs are in an expended position. The upper portions 36a, 36b of the legs 30a, 30b are preferably sized and configured to be received within leg receiving recesses formed within the table top 12. Advantageously, if the upper portions 36a, 36b have the same size and configuration, then the upper portions may be interchangeably attached to the table top 12. For example, as seen in FIG. 13, the bottom surface 18 of the table top 12 may include one or more leg receiving recesses 50 that are sized and configured to receive the upper portions 36a, 36b of the legs 30a, 30b. Preferably, the upper portions 36a, 36b are configured to be connected to selected leg receiving recesses by a snap fit, friction or interference fit, which allows the legs 30a, 30b to be quickly and easily attached and detached from the table top 12, but the legs can be connected to the table top 12 by any suitable manner. Further, latches, tabs, locking members, clips fasteners or other suitable devices may be used to retain the upper portions 36a, 36b in the leg receiving recesses. The leg receiving recesses 50 preferably generally extend from the front edge to the rear edge of the table top 12, but the leg receiving recesses may be formed in any desired portion of the table top and have any desired size and configuration depending, for example, upon the size and shape of the upper portions 36a, 36b of the legs 30a, 30b. The leg receiving recesses 50 preferably extend only a portion of the distance between the bottom 18 surface and the top surface 16, but the upper portion of the leg receiving recess may contact or engage the top surface of the table top. Advantageously, the leg receiving recesses 50 formed in the table top 12 allow the table 10 to be constructed without a frame, which reduces manufacturing costs. Additionally, the engagement between leg receiving recesses 50 and the legs 30a, 30b creates a stable support assembly 14. One skilled in the art will understand that the support assembly 14 can be connected to the table top 12 by other suitable means such as adhesives or mechanical fasteners. The leg receiving recesses may also include one or more retaining members 52. The retaining members 52 may flex or bend slightly to allow the upper portions 36a, 36b of the legs 30a, 30b to be inserted and removed from the leg receiving recesses. The retaining members 52 preferably resiliently return to their original positions to help secure the upper portions 36a, 36b of the legs 30a, 30b within the leg receiving recesses 50. It will be appreciated, however, that the leg receiving recesses 50 may not require the use of the retaining members 52 to hold the upper portions 36a, 36b of the legs 30a, 30b within the leg receiving recesses. In greater detail, the retaining members 52 preferably include a lip that extends over a portion of the leg receiving recess 50 and the lip deforms or deflects to the leg receiving recess. The lip preferably includes a generally hollow interior that is formed during the blow-molding process. In addition, the lip is preferably formed during the blow-molding process as part of an integral, one-piece structure. Advantageously, because the table top 12 preferably includes a plurality of leg receiving recesses 50 and the legs 30a, 30b can be connected to any suitable leg receiving recesses, this allows the legs to be connected to different leg receiving recesses. As discussed in greater detail below, this may allow the height of the table 10 to be adjusted. The legs 30a, 30b are preferably sized and configured to be quickly and easily connected and/or disconnected to any desired leg receiving recesses 50. In particular, the legs 30a, 30b are preferably pivotally connected to allow the legs to pivot or scissor back and forth with respect to one another at a wide variety of angles. This pivotal connection allows the legs 30a, 30b to be quickly and easily positioned so that the legs can be connected to the desired leg receiving recesses 50 in the table top 12. This pivotal connection also allows the legs 30a, 30b to be moved between a first or extended position, which is shown in solid lines in FIG. 4, and a second or collapsed position, which is shown in broken lines in FIG. 4. The legs 30a, 30b desirably fold generally flat and/or adjacent to each other in the second or collapsed position to allow the personal table 10 to be easily stored or collapsed. A channel 54 may be formed in the bottom surface 18 of the table top 12 to receive at least a portion of the legs 30a, 30b in the collapsed position. As seen in FIGS. 13-18, the channel 54 preferably interconnects two or more of the leg receiving recesses 50 and the channel preferably extends through a side of the table top 12 such as the right side 24. The channel 54 preferably has a shape similar to that of the body portions 34a, 34b of the legs 30a, 30b and the channel is preferably sized and configured to receive at least a portion of one or the body portions of the legs in the collapsed position, as shown in FIG. 18. This allows the legs 30a, 30b to be disposed generally adjacent to the table top 12, which reduces the required amount of storage space and this may also allow the personal tables 10 to be easily stacked. The legs 30a, 30b may be retained in the collapsed position in the channel 54 by one or more tabs 56. The tabs 56 are preferably located near an edge of the table top 12 and the tabs are preferably sized and configured to extend over a portion of the channel 54. The one or more tabs 56 deform or deflect to allow the legs 30a, 30b to be received or removed from the channel 54. The tabs 56 preferably include a generally hollow interior portion and the tabs are desirably formed during the blow-molding process as part of an integral, one-piece structure. One skilled in the art will understand that clips, fasteners and other types of devices may be used to secure the legs 30a, 30b in the collapsed position. The pivotal connection of the legs 30a, 30b and the plurality of leg receiving recesses 50 allows the height of the personal table 10 to be easily adjusted. As described in more detail below, the user can select which leg receiving recesses 50 to receive the legs 30a, 30b and this allows the desired height to be selected. For example, it will be appreciated that if the legs 30a, 30b are attached to two leg receiving recesses 50 that are close together, the table 10 will have a given height. However, if the legs 30a, 30b are attached to two leg receiving recesses 50 that are farther apart, then the table 10 will have a lower height.. The legs 30a, 30b can desirably be quickly and easily moved between the extended and collapsed positions. For example, if the support legs 30a, 30b are completely disengaged from table top 12, then the legs 30a, 30b can be folded into the collapsed position for storage. Alternatively, one or more of the legs 30a, 30b may be attached to the table top 12 when the legs in the collapsed position. Thus, a variety of different configurations are contemplated when table 10 is collapsed, including: (1) the support assembly 14 is completely disengaged from table top 12; (2) at least a portion of support assembly is connected to the table top while another portion of the support assembly is disconnected from the table top; and (3) at least a portion of support assembly is permanently coupled to table top. The support assembly 14 is preferably configured to maximize the legroom for the user when table 10 is in an upright position. For example, as shown in FIGS. 1-3, the body portions 34a, 34b of legs 30a, 30b are not centered with the lower portions 32a, 32b or upper portions 36a, 36b. Instead, the body portions 34a, 34b are disposed towards an end of the lower portions 32a, 32b and upper portions 36a, 36. Thus, when the table top 12 is coupled to the support assembly 14, as shown in FIG. 1 for example, the body portions 34a, 34b are located proximate the rear side 22 of the table top 12. Therefore, when the user is seated at front side 20 of table 10, the body portions 34a, 34b of the legs 30a, 30b are positioned farther away from the user so as to avoid impeding the user's space. In particular, because the body portions 34a, 34b of the legs 30a, 30b are positioned near the rear side 22 of table top 12, the user can slide the table 10 closer to their body. This allows the user to position the top surface 16 of the table top 12 in a desired position while still maintaining adequate legroom underneath the table 10. Thus, it can be seen that table 10 facilitates the ergonomic comfort of the user by reducing the need of the user to lean forward over the table in order to perform a particular task, such as reading or crafting. The offset body portions 34a, 34b also allow the user to slide a chair under the table 10 such that the support assembly 14 does not generally interfere with the chair. It will be appreciated, however, that the body portions 34a, 34b may be located in any suitable relation to the lower portions 32a, 32b and/or upper portions 36a, 36b of the legs 30a, 30b. As seen in FIG. 13, for example, a plurality of depressions 60 may be formed in the bottom surface 18 of the table top 12. The depressions 60 are preferably sized and configured to provide additional structural support and integrity to table top 12. The depressions 60 may cover a substantial portion of the bottom surface 18 of the table top 12 or the depressions may cover only a portion of bottom surface of table top. The depressions 60 may also be located in the leg receiving recesses 50 and/or channel 54, if desired. Alternatively, the table top 12 can be constructed without any depressions 60. In addition, while the depressions 60 are preferably located in the bottom surface 18, it will be appreciated that depressions may also be formed in any desired portion of the table top 12. As shown in FIG. 13, the depressions 60 may be formed in an array. The depressions 60 in the array may be located in a staggered, geometric, random or other suitable pattern. Additionally, the depressions 60 may extend from one surface to an opposing surface such that an end of the depression contacts or engages the opposing surface. The depressions 60 may also extend only a portion of the distance between the opposing surfaces. For example, the depressions 60 may extend from the bottom surface 18 to the top surface 16, but the depressions may also extend only a portion of the distance between the bottom and top surfaces. The depressions 60 advantageously increase the strength of the table 12. While it was previously believed that stronger structures were provided by making the walls thicker and/or adding structures such as ribbing, the depressions 60 provide the surprising and unexpected result that an increased number of depressions may provide a stronger structure and/or thinner walls may be used to construct the structure. Surprisingly, the depressions 60 increase the structural integrity of the structure despite forming disruptions in the continuity of bottom surface 18, and less plastic can be used to make the structure even though the plurality of depressions 60 are formed in the structure. The costs of manufacturing and transportation may be decreased because thinner plastic walls may be used to construct the table top 12, which may create a lighter weight table 10. Additionally, when blow-molded structures are formed, a certain amount of time must elapse before the structure can be removed from the mold. Blow-molded structures with thicker walls require a longer cooling time than structures with thinner walls. The depressions 60, however, allow table tops 12 with thinner plastic walls to be constructed and that reduces the cooling time before the structure can be removed from the mold. Significantly, a reduced cycle time increases the efficiency of manufacturing process. In addition, because less plastic is required, the cost of the table 10 may be reduced. Advantageously, the leg receiving recesses 50, retaining members 52, channels 54, extending tabs 56 and/or depressions 60 may be formed integrally with table top 12 during the blow-molding process as part of a one-piece structure. Advantageously, this allows a strong, lightweight structure to be created. It will be appreciated, however, that these structures do not have to be formed as part of a unitary structure and, in contrast, one or more of these structures can be formed after the blow-molding process. The personal table can also have other suitable configurations such as shown in FIGS. 16-18. In particular, the personal table 10 shown in FIGS. 16-18 includes a table top 12 with a plurality of receiving recesses 50 formed in the bottom surface 18 and this allows the support assembly 14 to be connected to the table top. This allows, as seen in FIG. 17 for example, the first leg 30a to be connected to one of the receiving recesses 50 disposed near the right side of the table top 12 and the second leg 30b to be connected to the receiving recess disposed near the left side of the table top. Advantageously, the first leg 30a can be selectively connected to any suitable receiving recess 50 disposed near the right side of the table top 12 in order to allow the height of the table 10 to be adjusted. For example, if the first leg 30a is connected to the receiving recess 50 disposed proximate the center of the table top 12, then the table 10 will have a first height such as twenty-eight inches. On the other hand, if the first leg 30a is connected to the receiving recess 50 disposed proximate the right side 24, then the table 10 will have a second height such as twenty-one inches. Of course, the first leg 30a could also be connected to one of the other receiving recesses 50 to create a table 10 with a height such as twenty-four or twenty-six inches. It will be appreciated that the table 10 could be sized and configured to have any suitable height and the table may include any desired number of receiving recesses 50 to allow the height of the table to be adjusted. The table top 12 shown in FIGS. 16-18 includes an outer edge 70 and a recessed center section 72. The recessed center section 72 is preferably located between the leg receiving recesses 50 disposed on the right side 24 of the table top 12 and the left side 26 of the table top. The recessed center section 72 may include one or more depressions 60 and the recessed center section preferably extends towards the top surface 16 of the table top 12. The table top 12 may also include one or more recessed outer sections 74 disposed towards the outer edge 70 of the table top. The recessed center section 72 and recessed outer sections 74 may be located in any desired configuration and the leg receiving recesses 50 and/or channel 54 may be located within one or more of these recessed sections. As best seen in FIGS. 16 and 17, at least a portion of the channel 54 is formed in the recessed center section 72. The channel 54, however, may be flush with the recessed center section 72 if desired. In addition, the table top 12 may include one or more generally planar portions 76 that allow instructions, warnings, safety labels, manufacturer information, operating instructions and other information to be attached to the table top. The table top 12 may also include one or more support grooves 78 or other desired types of reinforcement structures. Desirably, the support grooves 78 may be sized and configured to increase the strength and rigidity of the table top 12. In order to use the table 10 shown in FIGS. 16-18, one of the legs of the support assembly 14 is inserted into one of the desired leg receiving recesses 50 and the other leg is inserted into another of the desired leg receiving recesses. This allows a personal table 10 with the desired height to be created. In order to adjust the height of the personal table 10, one or both of the legs may be removed from their respective leg receiving recesses 50 and inserted into another desired leg receiving recess. In order to collapse the table 10, the first leg 30a is preferably removed from its leg receiving recess 50 and the legs 30a, 30b are positioned within the channel 54 as shown in FIG. 18. Advantageously, the extending tabs 56 may help hold the legs 30a, 30b in the collapsed position. When it is desired to use the table 10, the legs 30a, 30b are removed from the channel 54 and the first leg is inserted into the desired leg receiving recess 50. It will be appreciated that the entire support assembly 14 can be removed if desired or one of the legs may be permanently attached to the table top 12. It will be appreciated that the leg receiving recesses 50 may also be disposed along the length of table top 12. That is, the leg receiving recesses 50 may be disposed proximate the front side 20 and rear side 22 of the table top 12. Advantageously, this may provide additional uses for the personal table 10. Further, if desired, the leg receiving recesses 50 may be disposed along the length and/or width of the table top 12 depending, for example, upon the intended use of the table 10. From the foregoing description, the leg receiving recesses 50 allow the personal table 10 to be readily adjusted to various suitable heights. For example, the personal table 10 may be configured to have a maximum height, an intermediate height, and a minimum height. Thus, the table 10 may be configured to have a height that enables a user to stand and utilize the table, a height that is generally equal to the height of a counter top, and/or a height that enables the user to be seated at the table. Additionally, the height of the table 10 may be adjusted according to the desired use of the table. For example, the height of the table may be adjusted to allow the table to be used by children, or the table may have a height which allows it to be used as a television tray or table. Significantly, the various heights of table 10 can be predetermined and designed for any suitable purpose. This provides great flexibility and a wide variety of uses for table 10. FIG. 19 illustrates another aspect of a personal table 80. The personal table 80 includes a table top 12 with an outer wall or lip 82. The outer wall 82 a preferably extends generally downwardly from the bottom surface 18 of the table top 12 and it may form a boarder or edge to the table top. The outer wall 82 preferably encloses a central area 84 in which one or more receiving members 86 are located. Advantageously, the outer wall 82 may help hide parts of the table 80 from the view of the user and it may also help protect the user from unintentionally contacting parts of the table. The receiving members 86 include one or more curved receiving portions 88 that are sized and configured to receive the upper portions 36a, 36b of the legs 30a, 30b. The upper portions 36a, 36b of the legs 30a, 30b are inserted into the desired receiving portions 88 and the legs are preferably held within the receiving portions by a snap, friction or interference fit. It will be appreciated that the legs 30a, 30b may be attached to the receiving members 86 by any suitable means such as fasteners, clips, brackets, clasps and the like. As shown in FIG. 19, the table 80 includes four receiving members 86 that are located proximate the four corners of the table. The receiving members 86 may be integrally formed in the table top 12 during the blow-molding process to form a one-piece structure, or the receiving members may be attached to the table top 12. The receiving members 86 are preferably disposed within the central area 84 so that the receiving members are generally hidden from view by the lip 82. The receiving members 86 are also preferably generally parallel aligned and the receiving members are sized and configured to selectively receive the upper portions 36a, 36b of the legs 30a, 30b. It will be understood that the receiving members 86 may be positioned in any desired location and the table top 12 may include other features such as a channel 54 and/or depressions 60. The receiving members 86 provide a height adjustment mechanism for selectively increasing or decreasing the distance between the upper portions 36a, 36b of legs 30a, 30b of the support assembly 14, which allows the height of the table 80 to be adjusted. Advantageously, because the receiving members 86 preferably include a plurality of receiving portions 88, that allows the table to have a plurality of different heights. One skilled in the art will understand that the receiving members 86 may have any suitable number of receiving portions 88 and it is not required that all the receiving members have the same number of receiving portions. In order to use the table 80, one of the legs 30a, 30b of the support assembly 14 is inserted into a desired pair of receiving portions 88 in the receiving members 86. The other leg is then inserted into another desired pair of receiving portions 88 in the receiving members 86 to create a personal table 80 with the desired height. In order to adjust the height of the personal table 80, one or both of the legs 30a, 30b may be removed from their respective receiving portions 88 and inserted into other desired receiving portions. In order to collapse the table 10, one or both of the legs 30a, 30b are removed from the receiving portions 88 and the legs may be moved into a collapsed position. Another aspect is a personal table 90, as shown in FIGS. 20 and 21, which includes a table top 12 and a support assembly 14. The support assembly 14 includes legs 30a, 30b with a lower portion 32a, 32b, a body portion 34a, 34b and an upper portion 36a, 36b. The table top includes a lip 92 that is preferably disposed about the circumference of the table top and it encloses a central area 94. A leg attachment member 96 is preferably located proximate each end of the table top 12 and it is configured to allow the legs 30a, 30b to be connected to the table top. In particular, the leg attachment member 96 is preferably attached to the table top 12 by fasteners such as screws 98 and a plurality of grooves or channels 100 are formed in the leg attachment member. A receiving member 102 is sized and configured to be selectively attached to any of the desired grooves 100 and the receiving member allows the legs 30a, 30b to be selectively attached to the table top 12. The receiving member 102, for example, may be selectively connected to a desired groove 100 in the leg attachment member 96 and an upper portion 36a, 36b of a leg 30a, 30b may be selectively or permanently attached to the receiving member. This allows the leg 30a, 30b to be attached to the table top 12. In greater detail, the receiving member 102 may be selectively connected to the groove 100 by a friction, snap or interference fit, or other suitable means. The receiving member 102 may also be attached to the leg attachment member 96 by a locking member 104 that includes a handle 106 disposed near an edge of the table top 12. The receiving member 102 may be selectively attached to a desired groove 100 by the locking member 104. The upper portion 36a, 36b of the leg 30a, 30b may be attached to the receiving member 102 either before or after the receiving member is attached to the groove 100. Alternatively, the leg 30a, 30b may be permanently attached to the receiving member 102. As shown in FIG. 20, the legs 30a, 30b may be disposed in a collapsed position with the legs being positioned generally adjacent to the bottom surface 18 of the table top 12. In this collapsed position, the receiving members 102 are disposed in the grooves 100 proximate the edges of the table top 12. The receiving members 102 can then be released from the grooves 100 proximate the edges of the table top 12, for example by pulling the handle 106, and the receiving members are then connected to any desired groove 100 according to the desired height of the table 90. Another aspect of a personal table 110 is shown in FIGS. 22 through 26. The personal table 110 includes a table top 12 with a lip 112 and a central area 114 that is enclosed by the lip. Attached to the bottom surface 18 of the table top 12, preferably in the central area 114, are two height adjustment members 116a, 116b. The height adjustment members 116a, 116b allow the height of table top 12 to be altered by changing the relative positioning of legs 30a, 30b with respect to one another. In particular, the height adjustment members 116a, 116b allow the distance separating the upper portions 36a, 36b of the legs 30a, 30b to be changed, which changes the height of the personal table 110. In greater detail, the height adjustment members 116a, 116b preferably consist of dual hinge or pivoting members 118 with a connecting member 120 having a first end 122 and a second end 124. The first end 122 of the connecting member 120 is pivotally connected to the table top 12 by a base 123, but any suitable method may be used to attach the first end of the dual hinge member 118 to the table top. The second end 124 of the connecting member 120 is pivotally attached to the upper portion 36a, 36b of the legs 30a, 30b. Thus, the dual hinge members 118 are pivotally connected to the table top 12 and the legs 30a, 30b. As illustrated in FIGS. 23-26, the lengths of the connecting members 120 are preferably different. That is, one connecting member 120 is preferably longer than the other connecting member. In addition, the dual hinge members 118 also allow the upper portions 36a, 36b of the legs 30a, 30b to be positioned in two different positions. In particular, the dual hinge members 118 allow the upper portions 36a, 36b of the legs 30a, 30b to be positioned towards an edge of the table top or towards the center of the table top. Because the dual hinge members 118 allow the upper portions 36a, 36b of the legs 30a, 30b to be positioned in two different locations and the connecting members 120 preferably have different lengths, that allows the legs to be positioned into four different configurations and the table to have corresponding different heights. In greater detail, as shown in FIGS. 23-26, the first height adjusting member 116a may have a shorter connecting member 120 than the second height adjusting member 116b. For example, the length of the connecting member 120 of the first height adjustment member 116a may be approximately half the length of the connecting member of the second height adjustment member 116b. In particular, the length of the first height adjusting member 116a may be about one to two inches, and the length of the second height adjusting member 116b is preferably about five to six inches, but the connecting members may have any suitable length. Because the dual hinge members 118 are movable between two different positions and the connecting members 120 have different lengths, the table may have four different heights. For example, as seen in FIG. 23, the first height adjustment member 116a has the upper portion 36a of the leg 30a disposed towards the center of the table top 12 and the second height adjustment member 116b has the upper portion 36b of the leg 30b disposed towards the center of the table top. This creates a table with a maximum height. FIG. 24 shows the first height adjustment member 116a has the upper portion 36a of the leg 30a disposed towards the center of the table top 12 and the second height adjustment member 116b has the upper portion 36b of the leg 30b disposed towards the edge of the table top. This creates a table with an intermediate height. FIG. 25 illustrates the first height adjustment member 116a disposed towards the edge of the table top 12 and the second height adjustment member 116b disposed towards the center of the table top to create a table with an intermediate height. FIG. 26 shows both the first height adjustment member 116a and the second height adjustment member 116b disposed towards the edges of the table top 12, which creates a table with a minimum height. Advantageously, the height adjustment members 116a, 116b allow the table 110 to be readily adjusted to various suitable heights. Significantly, the various heights of the table 110 can be predetermined and designed for any suitable purpose. This provides great flexible and a wide variety of uses for the table. Further, the height adjustment members 116a, 116b can be used in connection with any suitable type of table or support structure. Further, please note that the above description of the dual hinge members 118 is but one example of a height adjustment member that may be used to adjust the height of the table. Accordingly, one skilled in the art will recognize that various modifications may be made to the height adjustment members 116a, 116b in order to suit the needs of a particular application. It will also be understood that the table can be constructed with only a single height adjustment member 116. For example, one leg 30a, 30b could be coupled to table top 12 using a height adjustment member 116 while the other leg is attached to table top 12 using a standard hinge or pivotal connection. FIGS. 27 and 28 illustrate another aspect of a personal table 130 that includes a support assembly coupled to a table top. The personal table 130 includes a lip 132 and a central area 134 that is generally enclosed by the lip. Four brackets 136 are attached to the bottom surface 18 of the table top 12 and the brackets are preferably located in the corners of table top. The brackets 136 are attached to the table top 12 by fasteners such as screws, but any suitable means may be used to connect the brackets to the table top. The brackets 136 are preferably elongated members with a slot 136 disposed towards the center of table top 12. The ends of the upper portions 36a, 36b of the legs 30a, 30b are preferably disposed within opposing slots and the slots allow the upper portions of the legs to slide along the length of bracket 136. Because both the legs 30a, 30b are slidably received within brackets 136, it will be appreciated that the legs can be configured to adjust the height of table 130. Alternatively, only one leg 30a, 30b may be slidably coupled to table top 12 via the brackets 136. The table 130 also includes a height adjustment mechanism 140 for selectively adjusting the height of the table by increasing or decreasing the distance between the upper portions 36a, 36b of legs 30a, 30b. The height adjustment mechanism 140 includes a ratchet assembly 142 that is pivotally connected to table top 12. The ratchet assembly 142 includes a gear 144 with a plurality of teeth 146 and a pair of outwardly extending arms 148. The arms 148 are attached to the legs 30a, 30b of the support assembly 14 by connectors 150 such as elongated rods. The ratchet assembly 142 also includes a pawl 152 that is configured to engage the teeth 146 on the gear 144. The pawl 152 is attached to a lever 154 that is accessible by a user at outer edge of table top 12. As shown in FIG. 27, the gear 144 may be rotated in a clockwise direction to position the upper portions 36a, 36b of the legs 30a, 30b closer together. Alternatively, as shown in FIG. 28, the gear 144 may be rotated in a counter-clockwise direction and the upper portions 36a, 36b of the legs 30a, 30b may be moved apart. Similar to that described above, when the upper portions 36a, 36b of the legs 30a, 30b are spaced closer together, the height of the table increases. On the other hand, when the upper portions 36a, 36b of the legs 30a, 30b are spaced farther apart, the height of the table decreases. It will be appreciated that the ratchet assembly allows the table to have a plurality of different heights. Although this invention has been described in terms of certain preferred embodiments, other embodiments apparent to those of ordinary skill in the art are also within the scope of this invention. Accordingly, the scope of the invention is intended to be defined only by the claims which follow. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention generally relates to tables and, in particular, to a light-weight table that may be adjustable in height and may have legs that can be collapsed into a storage position. 2. Description of Related Art Conventional tables are used for a variety of purposes and come in a wide array of designs. In some situations, it is desirable to have a smaller table for personal or individual use. For example, persons living in a small space, such as a studio apartment, may choose to use a smaller personal-sized table on which to dine or perform other tasks. Other persons may use a personal table to place beside a chair for the convenience of holding objects while reading, watching television or listening to the radio. Still others may use personal tables to perform tasks such as writing, working, or using a computer. Conventional tables often include table tops constructed from wood, particle board or metal. Table tops constructed from wood, particle board or metal, however, are often relatively heavy and this may make the table awkward or difficult to move. Conventional table tops constructed from wood or metal are also relatively expensive and the table tops must generally be treated or finished before use. For example, table tops constructed from wood must generally be sanded and painted, and metal table tops must be formed into the desired shape and painted. In addition, these relatively heavy table tops increase the cost of transportation, shipping, and storage of the tables. In order to decrease the weight of conventional tables, table tops can be constructed from relatively thin, light-weight materials. Disadvantageously, these light-weight table tops frequently require reinforcing members or other structural parts such as frames, railings, brackets and the like to strengthen the table top. These additional parts may increase the strength of the table top, but these additional parts also increase the weight of the table. In addition, these additional parts increase manufacturing costs and require additional time to assemble the table. Furthermore, these additional parts may have sharp edges that can injure the user's legs, arms or other body parts. Known tables may also allow the height of the table to be adjusted to suit the needs of the user. For example, the length of the table legs may be increased or decreased by a telescoping assembly. Disadvantageously, because the telescoping assemblies include overlapping components, the assembly is relatively heavy. Additionally, conventional tables may use other mechanisms to allow the height of the table to be adjusted, but these devices are often relatively complex and require additional parts, which increases the costs to manufacture and assemble the table. These complex designs may also result in tables that are relatively difficult to use. Another type of known table is a traditional card table in which each leg is pivotally connected to the table top by a brace and each leg individually folds against the table top. Known tables may attempt to reduce the inconvenience of individually folding legs against the table top by coupling two of the legs together by a long connecting rod. This may increase the stability of the table top and enable the user to simultaneously fold two legs into the collapsed position. The connecting rods, however, increase the cost of the table, reduce space under the table top, and may easily break or become disconnected. Conventional tables may also detachably connect the legs to the table top to allow the user to more easily collapse, move and store the table. Disadvantageously, the detachable legs often create a table that is not sturdy or stable. Additionally, moving a table with this type of attachment when the legs are still attached is often difficult because the legs may undesirably detach. These known types of table may include an attachment that mechanically secures the leg to the table top. These mechanical attachments, such as plastic or metal clips or brackets, often break or are otherwise damaged. Further, attachment of these devices to the table top may structurally weaken the table top, which may allow the table to unexpectedly fail. Further, attaching the four separate attachment mechanisms to the table top by fasteners such as screws or bolts may undesirably weaken the table top. Many conventional tables include four legs in order to support the table top above a surface such as the floor. The four separate legs, however, increase the weight of the table. In additional, the four legs require four separate attachment mechanisms to attach the legs to the table top, which increases the cost and complexity of the table. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>A need exists for a table that eliminates the above-described disadvantages and problems. One aspect of the present invention is a relatively small-sized table that is designed for use by a single person. This type of table that is intended for use by an individual is referred to as a personal table, but it will be appreciated that more than one person could use the table if desired. Advantageously, the personal table is relatively small and light-weight, which makes the table easy to move and transport. Significantly, because the table is sized and configured for personal use, it does not take up unnecessary space or provide a large amount of unused space. Therefore, the personal table provides ample space for a single user without requiring a large area or wasting unnecessary space. Another aspect of the personal table is it can be used for a wide variety of different situations and uses such as a table for supporting a television, computer, sewing machine, microwave, lamp, luggage, and the like. The table can also be used for a wide variety of other uses such as a bedside table, coffee table, night stand, desk, shop table, and the like. Further, the table can be used while performing a wide variety of tasks such as reading, writing, studying, working, etc. Thus, the personal table can be used in a number of different environments and it can perform numerous different tasks. Yet another aspect of the personal table is the height of the table can be readily adjusted. Advantageously, the adjustable height table allows it to be used for many different purposes, such as those discussed above. A further aspect of the personal table is the table top is support by a single pair of legs. The legs are preferably pivotally connected and the legs preferably allow the height of the table top to be easily adjusted. Significantly, because the table top is support by a single pair of legs, that provides additional leg room and/or storage room under the table. In addition, the single pair of legs is light-weight and easily attached to the table top. The single pair of legs can desirably support the table top and suitable objects placed on the personal table. Advantageously, because the personal table has a relatively small size, the single pair of legs can properly support the table. A still further aspect of the personal table is the legs are preferably movable between a use position and a storage position. The legs preferably extend outwardly from the table top in the use position and the legs support the table top above a surface such as the floor. In the storage position, the legs are preferably collapsed into a relatively compact area, which allows the table to be easily transported or stored. The legs, for example, may be placed adjacent and/or proximate to the bottom surface of the table top in the collapsed position. Another aspect of the personal table is the table top is preferably constructed from a lightweight material so that the table is easily portable and can be readily lifted and moved by a single person. Desirably, the table top is constructed from blow-molded plastic, such as high density polyethylene. The blow-molded plastic table top provides a rigid, high-strength structure that is capable of withstanding repeated use and wear. Advantageously, the blow-molded table top can be easily manufactured and formed into the desired size and shape. In addition, the blow-molded table top can form a structural component of the table to minimize the number of components and size of the table. Thus, frames, braces or other support members are not required to support the table top. Yet another aspect of the personal table is the legs can be attached to recesses and/or grooves formed in the table top. In particular, the legs are preferably attached to the table top by a snap, interference or friction fit. This connection of the legs to the table top may also allow the legs to be selectively removed or detached from the table top. Advantageously, because the legs do not require any fasteners or other structures to be connected to the table top, no stress points or other types of weakness are formed in the table top. Thus, the strength and rigidity of the table top is not decreased by forming holes or inserting fasteners into the table top. The legs may also be pivotally or slidably attached to the table top. One aspect of the personal table is both legs may be removably attached to the table top. This allows the legs to be easily removed for transportation and/or storage. In addition, the removal of both legs may allow the height of the table to be easily adjusted by attaching the legs to different grooves or recess in the table top. One of the legs, however, may be permanently or more securely attached to the table top, and the other leg may be more easily attached or detached from the table top. Thus, the selectively detachable leg may be detached from the table top when the height of the a table is desired to be adjusted and/or the table is desired to be moved or stored. Of course, both of the legs may be easily detached from the table top, but only one of the legs may be detached to allow, for example, the height of the table to be adjusted or to move the legs into a collapsed position. A further aspect of the personal table is the pair of legs are preferably pivotally connected by a pin, bolt or screw into a generally X-shaped configuration. The pivotal connection advantageously allows the legs to be quickly moved between the storage and use positions. The pivotal connection also allows the height of the table to be readily adjusted. Desirably, each leg includes a lower portion that contacts a support surface such as the floor, a body portion, and an upper portion that is sized and configured to be connected to the table top. The body portion of each of the legs may include two support members, which helps prevent twisting or undesirable torque on the connection of the upper and lower portions to the elongated body portion. Another aspect of the personal table is the legs can be attached to the table top via double hinge members. Advantageously, the legs can be pivotally attached by the double hinge members to the table top to allow the height of the table top to be adjusted. In particular, the double hinge members are preferably movable between different positions and that allows the height of the table top to be changed. The legs can also be slidably attached to the table top and a ratchet assembly may be used to selectively adjust the height of the table top. A further aspect of the personal table is the legs are preferably offset towards one side of the table top. Advantageously, because the legs are not placed in the center of the table, that provides enhanced legroom for the user. This also allows the table top to be positioned closer to the body of the user, which may be more convenient for the user. Advantageously, the personal table is relatively simple to manufacture because it preferably consists of a table top constructed from blow-molded plastic and a pair of pivotally interconnected legs. The blow-molded table top includes two opposing walls that are spaced apart, which increase the strength and rigidity of the table top. The blow-molded table top may also include one or more depressions or tack-offs to further increase the strength of the table top and/or interconnect the spaced apart walls. Significantly, a blow-molded table top is light-weight, durable, generally weather resistant and temperature insensitive, and it does not corrode, rust or otherwise deteriorate. The blow-molded table top can also be formed in various shapes, sizes, configurations and designs. Additionally, the personal table is easy to assemble, which reduces manufacturing and labor costs. Further, the consumer can easily assemble the personal table and the consumer will appreciate many of the aspects of the personal table such as the light-weight, easy height adjustment, portability, sturdiness, and wide variety of uses in any different environments. These and other aspects, features and advantages of the present invention will become more fully apparent from the following detailed description of preferred embodiments and appended claims. | 20050118 | 20070904 | 20050616 | 96010.0 | 1 | CHEN, JOSE V | PERSONAL TABLE | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,387 | ACCEPTED | Mouse model for psoriasis and psoriatic arthritis | A mouse that is deficient for c-Jun and JunB in the epidermis or in which deletion of c-Jun and JunB can be specifically induced in the epidermis, and methods for obtaining such mice. The mice and keratinocytes derived therefrom are useful as an animal model for psoriasis and psoriatic arthritis. | 1. A mouse that is deficient for c-Jun and JunB in the epidermis. 2. A mouse, in which deletion of c-Jun and JunB can be specifically induced in the epidermis. 3. The mouse of claim 1 or 2, in which deletion of c-Jun and JunB is achieved by expression of a constitutively active or inducible recombination enzyme in the epidermis. 4. A method for obtaining a mouse of claim 2, wherein a transgenic mouse having the c-Jun and JunB genes flanked with recognition sites for a site specific recombination enzyme is crossed with a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis. 5. The method of claim 4, wherein the recombination enzyme is Cre-recombinase, which is fused to the estrogene receptor, under the control of a keratinocyte-specific promoter. 6. A method for obtaining a mouse of claim 1, wherein a transgenic mouse having the c-Jun and JunB genes flanked with recognition sites for a site-specific recombination enzyme is crossed with a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis, and deletion of c-jun and junB is specifically induced in the epidermis. 7. The method of claim 6, wherein the recognition sites are loxP sites and the recombination enzyme is Cre-recombinase, which is fused to the estrogene receptor, under the control of a keratinocyte-specific promoter, and wherein epidermis-specific deletion of c-jun and junB is induced by applying an anti-estrogen. 8. The method of claim 7, wherein the anti-estrogen is applied by intraperitoneal injection or topical application. 9. The method of claim 7 or 8, wherein the anti-estrogen is tamoxifen. 10. Keratinocytes derived from a mouse of claim 1 or 2. 11. A mouse of claim 1 as an animal model for psoriasis and psoriatic arthritis in humans. | This patent application claims priority to provisional patent application No. 60/548,426 filed Feb. 27, 2004, which is hereby incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the field of psoriasis. 2. Background Art Psoriasis, affecting about 2% of the population, is one of the most common human skin disorders that affect skin and joints. It is characterized by complex alterations of various cell types. This includes epidermal hyperproliferation and altered differentiation, as well as angiogenesis and dilation of dermal blood vessels (Schön, 1999; Lebwohl, 2003). In addition, a mixed leukocytic infiltrate is seen. It is composed of activated T lymphocytes, neutrophiles within the dermis and epidermal microabscesses, lining macrophages, and an increased number of dermal mast cells. Cytokines including tumor necrosis factor-α (TNF-α), and interleukin-1 (IL-1), interferon-γ(INF-γ), IL-6, IL-8, vascular endothelial growth factor (VEGF) and transforming growth factor-α (TGF-α) are thought to mediate the psoriatic tissue alterations (Schön, 1999). For decades the ongoing controversy is whether psoriasis results from primary abnormalities in the epidermis or is immunologically based (Nickoloff et al., 2000). Although evidence is accumulating that it has an immunological basis others interpret psoriasis as a genetically determined, abnormal epithelial response pattern to infection and/or physicochemical skin insults. It has become clear that psoriatic skin is a hotbed of epidermal growth factors and inflammatory mediators. Supportive evidence of a key role for such mediators comes from patients who respond to immunsuppressive, anti-inflammatory, and antiproliferative therapies such as cyclosporine, methotrexate, tacrolimus, corticosteroids, and ultraviolet-light-activated psoralen. However, extensive efforts aimed at transgenically delivered inflammatory mediators or keratinocyte growth factors to the skin have not completely reproduced the psoriatic phenotype (Xia et al., 2003), which has thus far only been faithfully modeled in animals by transplanting psoriatic skin onto mice with severe combined immunodeficiency disease (SCID). So far no reported mouse model for psoriasis mimics all characteristics seen in psoriasis in humans, including psoriatic arthritis which is present in up to 40% of psoriasis patients. Since there is no naturally occurring animal skin disease mirroring both phenotype and immunopathogenesis of psoriasis, research into the pathogenesis of this common skin disorder has been severely hampered. Consequently, there is a need for an efficient and significant animal model for the study of psoriasis and for testing drug candidates effective in the treatment of this disorder. BRIEF SUMMARY OF THE INVENTION It was an object of the invention to provide an animal model for psoriasis, including psoriatic arthritis. In a first aspect, the invention relates to a mutant mouse which is deficient for c-Jun and JunB in the epidermis (junΔep*,junBΔep*). In a preferred embodiment, the deficiency of c-Jun and JunB is caused by a deletion of c-Jun and JunB achieved by expression of a constitutively active or inducible recombination enzyme in the epidermis. In a further aspect, the invention relates to a mutant mouse, in which deletion of c-Jun and JunB can be specifically induced in the epidermis. In a preferred embodiment, deletion of c-Jun and JunB is achieved by expression of a constitutively active or inducible recombination enzyme in the epidermis. In a further aspect, the present invention relates to a mutant mouse which is deficient for c-Jun and JunB. In an additional aspect, the present invention relates to a method for producing a mutant mouse that is deficient for c-Jun and JunB in the epidermis comprising crossing (a) a transgenic mouse comprising a genetic construct containing the c-Jun and JunB genes flanked with recognition sites for a site-specific recombination enzyme with (b) a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis, wherein deletion of c-Jun and JunB is specifically induced in the epidermis. In one embodiment, the deficiency of c-Jun and JunB in the epidermis of the mutant mouse is induced by applying an anti-estrogen. The anti-estrogen is applied by intraperitoneal injection or by topical application. An example of a suitable anti-estrogen is tamoxifen. In a further aspect, the present invention relates to a method for producing a mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis comprising crossing (a) a transgenic mouse comprising a genetic construct containing the c-Jun and JunB genes flanked with recognition sites for a site specific recombination enzyme with (b) a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis. In one embodiment, the epidermal cells in the mutant mouse comprise a genetic construct comprising a keratinocyte-specific promoter operably linked to a nucleic acid molecule encoding Cre-recombinase, wherein said promoter is also operably linked to an estrogen receptor. In another embodiment of the invention, isolated keratinocytes may be derived from the mutant mouse that is either deficient for c-Jun and JunB in the epidermis or the mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis. Furthermore, the present invention is directed to the method of testing a drug to treat psoriasis in a human comprising administration of the drug to the mutant mouse that is deficient for c-Jun and JunB in the epidermis. Additionally, the present invention is directed to the method of testing a drug to treat psoriatic arthritis in a human comprising administration of the drug to the mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 A.) Schematic outline of the floxed c-jun and floxed junB locus and the inducible Cre-ER transgene used to delete both genes upon tamoxifen application. B.) Treatment scheme. Adult mice were injected intraperitoneally 5 times with 1 mg tamoxifen and analyzed 14 days thereafter. C.) Southern Blot for c-jun and junB to confirm deletion of both genes after tamoxifen application specifically in the epidermis of adult mice. D.) RPA (RNAse protection assay) for AP-1 genes after deletion of c-jun and junB demonstrating downregulation of all AP-1 genes beside fra-2. FIG. 2 A.) Macroscopy of ear, feet and tail from adult mice after inducible deletion of c-jun and junB in the epidermis of adult mice resembling psoriasis. B.) Histology of psoriatic mouse ears reflecting the hallmarks of psoriasis: abnormally thickened epidermis, parakeratosis (nucleated keratinocytes in the cornified layer), thickened keratinized upper layer (hyperkeratosis), and fingerlike epidermal projections into the dermis (rete ridges). Epidermal microabscesses and the typical inflammatory cell infiltrate are seen: intraepidermal T-cells (CD3 staining), increased numbers of neutrophils in the epidermis (esterase staining), and macrophages in the dermis (esterase- and F4/80-staining). C.) H&E staining from affected mouse finger demonstrating granulocytic infiltrates into the joint region similar to psoriatic arthritis. DETAILED DESCRIPTION OF THE INVENTION The solution of the problem underlying the invention is based on the molecular mechanisms associated with the transcription factor AP-1. The transcription factor AP-1 is generated by a series of dimers of products of the Fos, Jun, and CREB/ATF protein families (Eferl and Wagner, 2003), as well as other bZip proteins. In addition, associations have been observed between Fos or Jun and the p65 subunit of NFκB (Stein et al., 1993), and ATF-2 and p50-NFκB (Du et al., 1993). Combinatorial association can draw on three Jun genes (c-jun, junB, junD), four Fos genes (c-fos, fosB, fra-1, fra-2) and several CREB/ATF genes. Despite the high degree of homology in the overall structural features, the different members of the Fos, Jun and CREB families exhibit significant differences, which lead to subtle differences in DNA binding and transcriptional activation (Angel and Herrlich, 1994) suggesting specific functions in gene regulation for individual dimers. The members of the AP-1 family are engaged in the control of cell proliferation as well as various types of differentiation, and also in neural function and stress responses. AP-1 is one of the key factors that translate external stimuli both into short- and long-term changes of gene expression. The transcription factor c-Jun interacts with related and unrelated transcription factors, gaining influence on different and seemingly unrelated signal pathways controlling diverse target genes. c-Jun receives regulatory input originating outside of the cell, traversing the plasma membrane, cytoplasm, and nuclear envelope in a cascade of biochemical reactions (Herrlich and Ponta, 1989; Ransone and Verma, 1990; Karin and Smeal, 1992). These signals can modify the transcription of the c-jun gene or affect the activity of the c-Jun protein post-translationally. The regulation of c-Jun's transactivation potential takes place at two different levels: increased phosporylation in the transactivation domain causes enhanced transcriptional activity, and enhanced binding to DNA is due to dephosphorylation in the DNA binding region (Sachsenmaier and Radler-Pohl, 1994). Unstimulated mammalian cells contain low, but detectable, amounts of c-Jun protein. In this state c-Jun is phosphorylated constitutively at serines and threonines close to its C-terminal DNA binding domain. Phosporylation in this region markedly reduces DNA binding and transactivation ability of c-Jun in vitro (Boyle et al., 1991) and in vivo (Lin et al., 1992). In contrast to the negative effect of hyperphosphorylation in DNA binding, enhanced phosphorylation at the N-terminus is required for the activation of the transactivation function of c-Jun. Serines 73 and 63 are located close to a stretch of amino acids described as the “proline-rich region”, which is required for transactivation and can serve as in vitro substrates for mitogen-activated protein (MAP) kinases (Pulverer et al., 1991). Transcriptional regulation by c-Jun is highly cell type dependent (Imler et al., 1988; Bohmann and Tjian, 1989; Baichwald and Tjian, 1990), because of different upstream activators, partner molecules, or downstream targets present in the different cell types. A functional role for c-Jun in the skin has been suggested for differentiation and carcinogenesis. Since c-jun knock-out mice are not viable (Johnson et al., 1993; Hilberg et al., 1993), the consequence of lacking c-Jun in skin development and skin carcinogenesis could only be investigated by generation of conditional c-jun knock-out mice (c-junΔep) (Zenz R. et al., 2003; Li et al., 2003). Mice lacking c-jun in keratinocytes (c-junΔep) develop normal skin but express reduced levels of EGFR in the eyelids, leading to open eyes at birth, as observed in EGFR null mice. Primary keratinocytes from c-junΔep mice proliferate poorly, show increased differentiation, and form prominent cortical actin bundles, most likely because of decreased expression of EGFR and its ligand HB-EGF. In the absence of c-Jun, tumor-prone K5-SOS-F transgenic mice develop smaller papillomas, with reduced expression of EGFR in basal keratinocytes. Thus, using three experimental systems, we showed that EGFR and HB-EGF are regulated by c-Jun, which controls eyelid development, keratinocyte proliferation, and skin tumor formation. All the Jun proteins (c-Jun, JunB and JunD) are similar with respect to their primary structure and their DNA-binding specificity. However, JunB, due to a small number of amino acid changes in its basic-leucine zipper region exhibits a 10-fold weaker DNA-binding activity and a decreased homodimerization property compared to c-Jun. Transfection studies have suggested that junB is a repressor of AP-1 mediated transactivation and transformation most likely due to the preferential formation of inactive c-Jun/junB dimers (Chiu et al., 1989; Deng and Karin, 1993). However, in vitro and in vivo data have demonstrated that JunB can also be a strong transactivator depending on both the interacting partner and the promoter context (Chiu et al., 1989; Li et al., 1999). Since junB knock-out mice are not viable (Schorpp-Kistner et al., 1999), the consequence of lacking JunB in skin development and skin carcinogenesis can only be investigated by generation of conditional junB knock-out mice (junBΔep). Depending on the experimental system, c-Jun and JunB have been thought to have opposite functions in regulating gene expression, thereby influencing the biological output of various external and internal signals triggering AP-1 activity. To verify this, in the experiments leading to the invention, a novel experimental system was used by generating epidermis-specific double knock-out mice that are deficient for both c-jun and junB (c-junΔep, junBΔep). Unexpectedly, these mice die shortly after birth preventing the analysis of phenotypes at later stages in the development of these mice. Therefore, in the experiments of the invention, an inducible conditional knock-out mouse that is deficient for c-jun and junB in the epidermis was generated. For clarity, the terminology and abbreviations used herein have the following meanings: c-junf/f; junBf/f or c-junf/f, junBf/f, respectively, refers to mice with a floxed c-Jun or junB locus or mice with floxed c-Jun and JunB loci, respectively. c-junf/f K5-Cre-ER (or junBf/f K5-Cre-ER or c-junf/f, junBf/f K5-Cre-ER, respectively) refers to the floxed mice, in which the respective gene(s) are not (yet) deleted, since Cre needs to be activated first. Activation of Cre, and consequently deletion of the gene(s), is achieved by applying tamoxifen. (c-junf/f, junBf/f K5-Cre-ER mice are representative for the above-defined mice, in which deletion of c-Jun and JunB can be specifically induced in the epidermis.) c-junf/f K5-Cre (or junBf/f K5-Cre or c-junf/f, junBf/f K5-Cre, respectively), refers to mice in which the respective gene(s) have been deleted in the epidermis (Cre is in the active status). c-junf/f, junBf/f K5-Cre mice are representative for the above-defined mice, which are deficient for c-Jun and JunB in the epidermis (such mice are also designated “c-junΔep*, junBΔep* mice”). The constituents K5, Cre and ER can be replaced by any other suitable epidermis-specific promoter, recombination enzyme or gene encoding a biological molecule, respectively, which, upon binding of its ligand, induces activation of the recombination enzyme, e.g. another hormone receptor like the progesterone receptor binding domain, which is activated upon binding of an antiprogestin, e.g. RU486 binding (Minamino et al., 2001). In a further aspect, the invention relates to methods for generating c-junΔep*, junBΔep* mice. The principle of suitable methods is based on known protocols for generating transgenic mice, preferably on embryonic stem (ES) cell technology. The essential features of suitable preferred methods for obtaining the c-junΔep*, junBΔep* mice of the invention are, on the one hand, that the c-Jun and JunB genes are flanked with recognition sites for a site specific recombination enzyme (recombinase), and that, on the other hand, the recombinase can be provided by crossing the conditional knock-out mouse with a transgenic mouse expressing a constitutively active or inducible recombinase in the tissue of interest, i.e. the epidermis. Epidermis-specific expression can be achieved by using a promoter specific for skin cells, in particular keratinocytes; examples for suitable promoters are K5, K6, K10 or K14 (Jiang et al., 1991). In the experiments of the invention, the inducible gene deletion system enabling to delete both genes in adult mice, as described by Vasioukhin et al., 1999), was used. This system allows to prevent postnatal lethality of c-junΔep, junBΔep mice, which would not allow for analysis of phenotypes at later stages in the development. This system uses a K5-Cre-ER transgenic mouse line, which expresses a Cre-recombinase estrogene receptor fusion under the control of the keratinocyte-specific Keratin 5 promoter (K5) specifically in the epidermis. Using this system, both genes in adult mice can be deleted by consecutive intraperitoneal tamoxifen injection (Brocard et al., 1999; Vasioukhin et al., 1999). In keratinocytes expressing the Cre-ER fusion protein tamoxifen, an anti-estrogene, binds to the mutated estrogen receptor domain. This mutated fusion protein does not bind the endogenous 17β-estradiol, whereas it binds the synthetic ligand tamoxifen (Danielian et al., 1993). Tamoxifen binding is inducing a conformational change in the protein structure leading to an active Cre-recombinase. The active Cre-recombinase is transported into the nucleus and deletes the DNA-sequences between 2 loxP sites (floxed gene). For obtaining the epidermis-specific double knock-out mice of the invention, which are deficient for both c-jun and junB mice, according to a preferred embodiment, the inducible loxP/Cre system is used. To date, this system is considered to be the most reliable experimental setup for spatio-temporally controlled site-specific somatic gene deletion in vivo. The deletion of the gene(s) of interest (in the case of the present invention c-jun and junB) can be induced either by intraperitoneal injection or topic application of an anti-estrogen like tamoxifen or OH-tamoxifen to the skin (Vasioukhin et al., 1999). Alternatively to the loxP/Cre-system, other spatio-temporally controlled site-specific somatic gene deletion systems can be used to generate epidermis-specific double knock-out mice for c-jun and junB. Examples for such alternative methods for engineering the conditional knock-out mice of the invention are the Flp-FRT and the phiC31-att site-specific recombinase systems. As the loxP/Cre-system, these systems fulfill the requirements of having the gene(s) of interest flanked with recognition sites for the site specific recombination enzyme and of providing the recombination enzyme by crossing the conditional knock-out mouse with a transgenic mouse expressing a constitutively active or inducible recombinase in the tissue of interest (Branda and Dymecki, 2004). Alternatively to spatio-temporally controlled site-specific somatic gene deletion systems, siRNA techniques can be used for skin-specific gene silencing. Recently, plasmid-based systems using RNA-polymerase III promoters to drive short hairpin RNA (shRNA) molecules have been established to produce siRNA and the generation of knockdown ES cell lines with transgenic shRNA was reported (Kunath et al., 2003). Furthermore, viral-mediated delivery for specific silencing of target genes in liver and brain in mice through expression of small interfering RNA (siRNA) has been established (Xia et al., 2002). These systems can be adapted to generate knockdown mice or knocking down c-jun and junB in the epidermis of mice, e.g. by designing siRNA constructs that are expressed in the epidermis of mice after delivery by means of suitable gene delivery protocols. In a further aspect, the invention relates to keratinocytes derived from a mouse which is deficient for c-Jun and JunB in the epidermis (junΔep*, junBΔep*) or from a mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis. Keratinocytes can be obtained according to known methods, e.g. by using a protocol as described by or by Carroll et al., 1995, Carroll and Molès, 2000, or the following protocol (described in U.S. Pat. No. 6,566,136): Sections of skin obtained from sacrificed mice that have been shaved and washed are separated in dermis and epidermis, e.g. by treatment with trypsin, for example by flotation of the samples of skin tissue in a trypsin solution (for example about 0.5%) during a time sufficient to provoke cell separation. The dermis is separated and the epidermis is subsequently placed in a medium for achieving a suspension. The medium for achieving a suspension may contain a solution of soy trypsin inhibitor (SBTI) and is put in contact with the cells for a time sufficient to inactivate the trypsin and to provoke the release of the cells. The cells are grown in a serum-free tissue culture medium and filtered in order to obtain the desired keratinocytes. The resulting primary keratinocytes are subsequently seeded, in a suitable cell concentration, e.g. about 1.2×104 cells/cm2, on previously coated culture plates. The culture plates are usually coated with a composition that increases fixation and growth of keratinocytes, usually a solution containing fibronectin and of collagen type I. It was surprisingly found in the experiments of the invention that mice, after induced epidermis-specific deletion of c-jun and junB (c-junΔep*;junBΔep* mice), develop a psoriasis-like disease reflecting the hallmarks of psoriasis in humans within 2 weeks after tamoxifen injection. This phenotype was only seen after deletion of both c-jun and junB, but not after epidermis-specific deletion of c-jun or junB alone. Thus the invention relates, in a further aspect, to the use of c-junΔep*, junBΔep* mice as an animal model for psoriasis and psoriatic arthritis. The present invention provides a unique mouse model recapitulating many of the histological and molecular characteristics seen in the skin and joints of psoriatic patients. The phenotype develops very rapidly with 100% efficiency. The disease is not characterized by a generalized inflammatory response, but is prominent to hairless areas of the skin (ears, paws and tail) reminiscent of the symmetrically distributed psoriatic lesions in humans which are well demarcated from adjacent symptom-less skin. The diseased epidermis mirrors the changes in the cytokine and chemokine network reported for psoriasis. Expression profiling revealed further evidence that the changes in gene expression resemble most of the documented genetic changes described for human psoriasis. The c-junΔep*, junBΔep* mice of the invention and keratinocytes derived therefrom are useful for testing drugs against psoriasis and psoriatic arthritis in vivo. For example, given the role for pro-inflammatory cytokines such as IL-1, IL-8 and TNF-α in the pathogenesis of psoriasis, the mice of the invention may be utilized to evaluate specific inhibitors of these cytokine pathways or to test compounds whether they have an inhibitory effect. A specific illustration is the evaluation of inhibitors of the TNF-α pathway. For instance, c-junf/f, junBf/f K5-Cre-ER mice are treated with tamoxifen to obtain junΔep*, junBΔep* mice that develop the psoriasis-like disease. Upon first observation of symptoms, e.g. skin abnormality, the mice receive an inhibitor of this cytokine, e.g. a monoclonal antibody against mouse TNF-α, a well documented inhibitor of this cytokine in vivo. The mice are then be observed for the progression of skin lesions and the extent of disease progression can be compared to placebo-treated animals. Novel inhibitors of the TNF-α pathway, such as decoy receptors, TNF-synthesis inhibitors, MAP kinase inhibitors or therapeutic siRNA can also be used and the effects of treatment can be compared to anti-TNF-α treated animals. Likewise, test compounds, e.g. from compound libraries, can be applied to the animals and the effect of the compounds evaluated. The extent of lesion development post-treatment as well as the histopathologic makeup of the lesion can be analyzed (Carroll et al., 1995). Also the effect of compounds on disease induction can be determined by treating c-junf/f, junBf/f K5-Cre-ER mice prior to tamoxifen administration. Changes in systemic markers of inflammation, such as cytokine levels, acute phase proteins, lymphocyte subsets and immunoglobulin levels and isotypes can be evaluated. The extent of inflammation pre- and post-treatment may also be assessed through determining the vascular permeability of diseased skin using extravasation markers such as Evans blue dye or 125I labeled albumin. The animal model of the invention is not limited to the evaluation of inhibitors of pro-inflammatory cytokines. For instance, novel inhibitors of leukocyte trafficking, such as adhesion molecules or chemokines, can be tested in the model similar to the aforementioned protocol. Also, specific inhibitors of the immune system such as inhibitors of T-cell activation, cytokine production or co-stimulation can be used. Agents or methods aimed at the induction of T regulatory cells can also be assessed. Finally, the animal model of the invention is useful to test the effect of modulators directed specifically against keratinocyte function or other cells of the skin. Such agents can be evaluated both in vivo and in vitro. For instance, animals can be induced for disease as described above and keratinocyte/skin specific agents applied via topical or systemic routes. The effect of such agents, or test compounds, on lesion development can be measured via histopathologic analysis (Carroll et al., 1995) and compared to untreated animals. Likewise, primary keratinocyte cultures or keratinocyte lines can be established in vitro from diseased animals using standard protocols (Carroll et al., 1995). Test compounds can be administered to the cultured cells in various doses and the effect on keratinocyte proliferation, viability, morphology and cytokine/growth factor production can be evaluated. Furthermore, cultured double knock-out keratinocytes, which can be obtained from the mice of the invention according to standard protocols, e.g. as described by Carroll et al. 1995; Carroll and Molès, 2000; Zenz et al., 2003, or in vitro skin tissue equivalents (Szabowski et al., 2000) or three-dimensional skin culture models (Carroll and Molés, 2000) can be used to screen for drugs inhibiting the production of keratinocytes-derived growth factors and cytokines responsible for psoriasis. EXAMPLES In the Examples, the following materials and methods were used: Generation of junBf/f Mice A floxed and frt-flanked neomycin resistance and thymidine kinase gene selection cassette was inserted into a SmaI site present in the 5′ untranslated region (UTR) of junB. The 3′ loxP site was inserted into the XhoI site, 161 bp downstream of the translation stop codon. A diphtheria toxin gene was included for selection against random integrants. The linearized targeting construct was electroporated into HM-1 ES cells and the identification of homologous recombinants by PCR using two sets of primers was performed as described previously (Schorpp-Kistner et al., 1999). The neomycin and thymidine kinase genes were deleted by transient transfection of a vector expressing flp recombinase. Two ES cell clones carrying a floxed allele of junB were injected into C57BL/6 blastocysts and several chimeras from one ES cell clone transmitted the mutant allele to their offspring. Generation of c-junΔep*; junBΔep* Mice Mice carrying a floxed c-jun allele (c-junf/f; Behrens at al., 2002) were crossed to mice carrying a floxed junB allele (junBf/f, Kenner et al., 2004) to obtain mice double-floxed mice (c-junf/f; junBf/f). Double floxed mice were crossed to transgenic mice expressing the Cre recombinase-estrogene receptor fusion under the control of the keratinocyte-specific Keratin 5 promoter (K5-Cre-ER; Brocard et al., 1997) to obtain c-junf/f; junBf/f and c-junf/f; junBf/f; K5-Cre-ER mice. Inducible Deletion of -junf/f and junBf/f 8 weeks old experimental mice (c-junf/f; junBf/f; K5-Cre-ER) and control mice (c-junf/f; junBf/f) were injected intraperitoneally 5 times with 1 mg tamoxifen (Sigma; Vasioukhin et al., 1999). Southern Blot and RNase Protection Assay (RPA) For the c-jun Southern blot, 10 μg of epidermal DNA was digested with XbaI (for c-jun) yielding a 6.9 kb fragment for the floxed c-jun allele and a 3.3 kb fragment for the deleted c-jun allele (Behrens et al., 2002). For the junB Southern 10 μg of genomic DNA was digested with PstI yielding a 2.3 kb fragment for the floxed junB allele and a 0.7 kb fragment for the deleted junB allele. For detection of the bands a 176 bp PstI/HindIII fragment of junB was used as probe (Kenner et al., 2004). For the RNase protection assay total epidermal RNA was isolated with the TRIZOL protocol (Sigma). RNase protection assays were performed using the RiboQuant multi-probe RNase protection assay systems mJun/Fos (PharMingen) according to the manufacturer's protocol. Histology Tissues were fixed overnight with neutral buffered 4% PFA at 4° C. and either directly or after decalcification (bone) in 0.5% EDTA for 12 days embedded in paraffin. Five-micrometer sections were stained either with hematoxylin and eosin (H&E) or processed further. Immunohistochemical staining for anti CD3 and F4/80 (Santa Cruz) was performed after antigen-retrieval (Dako S1699) with the MultiLink Dako system (Dako E0453) according to the manufacturer's recommendations. Example 1 Generation of c-junΔep*; junBΔep* Mice c-junf/f; junBf/f mice were crossed to K5-Cre-ER transgenic mice and heterozygous progenies were intercrossed to get c-junf/f; junBf/f; K5-Cre-ER and c-junf/f; junBf/f mice. The approach to delete c-jun and junB in the epidermis is outlined in FIGS. 1A and 1B. In brief, 8 weeks old experimental mice (c-junf/f; junBf/f; K5-Cre-ER) and control mice (c-junf/f; junBf/f) were injected intraperitoneally 5 times with 1 mg tamoxifen. 2 weeks after the last injection the mice were analyzed. The deletion of c-jun and junB was analyzed by Southern blot and RPA (RNAse protection assay). Southern blot analyses for c-jun and JunB deletion (FIG. 1C) showed deletion in both cases. The remaining signal for floxed c-jun and floxed junB is explained by incomplete deletion and the inflammatory infiltrate seen in the epidermis of c-junΔep*; junBΔep* mice (FIG. B). Quantification of AP-1 mRNA in the epidermis of c-junΔep*; junBΔep* mice showed significant down regulation of c-jun and junB mRNA and also for other AP-1 genes except fra2. Example 2 Characterization of c-junΔep*; junBΔep* Mice Mice obtained according to the treatment described in Example 1 develop a phenotype resembling psoriasis within 2 weeks. Hairless skin like ear, tail and feet were dramatically affected (FIG. 2A). Histological examination (FIG. 2B) revealed abnormally thickened epidermis, parakeratosis (nucleated keratinocytes in the cornified layer), thickened keratinized upper layer (hyperkeratosis), and fingerlike epidermal projections into the dermis (rete ridges). Furthermore, epidermal microabscesses and the typical inflammatory cell infiltrate are seen: intraepidermal T-cells (CD3 staining), increased numbers of neutrophils in the epidermis (esterase staining), and macrophages in the dermis (esterase- and F4/80-staining). H&E staining from affected mouse finger demonstrating granulocytic infiltrates into the joint region resembling psoriatic arthritis (FIG. 2C). REFERENCES Baichwal V. R. and Tjian R. (1990). Control of c-Jun activity by interaction of a cell-specific inhibitor with regulatory domain d: Differences between v- and c-Jun. Cell 63, 815-25. Behrens A., Sibilia M., David J P., Mohle-Steinlein U., Tronche F., Schutz G., Wagner E F. (2002). Impaired postnatal hepatocyte proliferation and liver regeneration in mice lacking c-jun in the liver. EMBO J. 21, 1782-90. Bohmann D. and Tjian R. (1989). Biochemical analysis of transcriptional activation by Jun: Differential activity of c- and v-Jun. Cell 59, 709-17. Boyle W. J., Smeal T., Defize L. H. K., Angel P., Woodgett J. R., Karin M., and Hunter T. (1991). Activation of protein kinase C decreases phosphorylation of c-Jun at sites that negatively regulate its DNA-binding activity. Cell 64, 573-584. Branda C. S. and Dymecki S. M. (2004). Talking about a Revolution. The impact of site-specific recombinases on genetic analyses in Mice. Dev. Cell 6(1):7-28. Brocard J., Warot X., Wendling O., Messaddeq N., Vonesch J L., Chambon P., Metzger D. (1997). Spatio-temporally controlled site-specific somatic mutagenesis in the mouse. Proc. Natl. Acad. Sci. 94, 14559-63. Carroll J M., Luetteke N C., Lee D C., Watt F M. (1995). Suprabasal integrin expression in the epidermis of transgenic mice results in developmental defects and a phenotype resembling psoriasis. Cell 83:957-968. Carroll J M, Molès J P. (2000) A three-dimensional skin culture model for mouse keratinocytes: application to transgenic mouse keratinocytes. Exp Dermatol 2000: 9: 20-24. Chiu R., Angel P., Karin M. (1989). Jun-B differs in its biological properties from, and is a negative regulator of, c-Jun. Cell 59, 979-86. Danielian P S., White R., Hoare S A., Fawell S E., Parker M G. (1993). Identification of residues in the estrogene receptor that confer differential sensitivity to estrogen and hydroxytamoxifen. Mol Endocrinol 7(2):232-40. Deng T., Karin M. (1993). JunB differs from c-Jun in its DNA-binding and dimerization domains, and represses c-Jun by formation of inactive heterodimers. Genes Dev. 7(3):479-90. Du W., Thanos D., and Maniatis T. (1993). Mechanisms of transcriptional synergism between distinct virus-inducible enhancer elements. Cell 74, 887-98. Eferl, R. and Wagner, E. F. (2003). AP-1: A double-edged sword in tumorigeneis. Nature Reviews Cancer 3, 859-868. Herrlich P. and Ponta H. (1989). “Nuclear” oncogenes convert extracellular stimuli into changes in the genetic program. Trends Genet. 5: 112-5. Imler J. L., Ugarte E., Wasylyk C. and Wasylyk B. (1988) v-jun is a transcriptional activator, but not in all cell lines. Nucleic Acids Res. 16, 3005-12. Hilberg F., Agguzi A., Howells N., and Wagner E. F. (1993). c-Jun is essential for normal mouse development and hepatogenesis. Nature 365, 179-181. Jiang C K., Epstein H S., Tomic M., Freedberg I M. and Blumenberg M. (1991). Functional comparison of the upstream regulatory DNA sequences of four human epidermal keratin genes. J. Invest. Dermatol., Vol 96, 162-167. Johnson R. S., van Lingen B., Papaioannou V. E., and Spiegelman B. M. (1993). A null mutation at the c-jun locus causes embryonic lethality and retarded cell growth in culture. Genes Dev. 7, 1309-1317. Karin M. and Smeal T. (1992). Control of transcription factors by signaling transduction pathways: The beginning of the end. Trends Biochem. Sci. 17, 418-22. Kenner L, Hoebertz A, Beil T, Keon N, Karreth F, Eferl R, Scheuch H, Szremska A, Amling M, Schorpp-Kistner M, Angel P, Wagner E F. (2004): Mice lacking JunB are osteopenic due to cell-autonomous osteoblast and osteoclast defects. J Cell Biol. 164(4):613-23. Kunath T., Gish G., Lickert H., Jones N., Pawson T., Rossant J. (2003). Transgenic RNA interference in ES cell derived embryos recapitulates a genetic null phenotype. Nat. Biotchnol. 21(5): 559-61 Lebwohl M (2003). Psoriasis. Lancet 361(9364):1197-204 Li B., Tournier C., Davis R J., Flavell R A. (1999). Regulation of IL-4 expression by the transcription factor JunB during T helper cell differentiation. EMBO 18(2):420-32. Li G., Gustafson-Brown C., Hanks S K., Nason K., Arbeit J M., Pogliano K., Wisdom R M., Johnson R S. (2003). c-jun is essential for organization of the epidermal leading edge. Dev. Cell 4(6): 865-77. Lin A., Frost J., Deng T., Smeal T., al-Alawi N., Kikkawa U., Hunter T., Brenner D., and Karin M. (1992). Casein kinase II is a negative regulator of c-Jun DNA binding and AP-1 activity. Cell. 70, 777-89. Minamino T, Gaussin V, DeMayo F J, Schneider M D (2001). Inducible gene targeting in postnatal myocardium by cardiac-specific expression of a hormone-activated Cre fusion protein. Circ Res. Mar 30; 88(6): 587-92 Nickoloff B J., von den Driesch P., Raychaudhuri S P., Boehncke W-H., Morhenn V B., Farber E M., Holik M F., Schröder J M. (2000). Is psoriasis a T-cell disease? Exp Dermatol 9: 359-375. Pulverer B. J., Kyriakis J. M., Avruch K., Nikolakaki E., and Woodgett J. R. (1991). Phosphorylation of c-jun mediated by MAP kinases. Nature 353, 670-674. Ransone L. J. and Verma I. M. (1990). Nuclear proto-oncogenes Fos and Jun. Annu. Rev. Cell Biol. 6, 539-57. Sachsenmaier C. and Radler-Pohl A. (1994). Regulation of c-Jun activity by phosphorylation. In: The fos and jun families of transcription factor/edited by Peter E. Angel and Peter A. Herrlich. CRC Press. pp. 61-70. Schön M P (1999). Animal models of psoriasis—what can we learn from them? J Invest Dermatol. 112(4):405-10 Schorpp-Kistner M., Wang Z Q., Angel P., Wagner E F. (1999). JunB is essential for mammalian placentation. EMBO J. 18(4):934-48. Stein B., Baldwin A. S. Jr., Ballard D., Greene A, Angel P. and Herrlich P. (1993). Cross-coupling of the NF(Bp65 and Fos/Jun transcription factors produces potentiated biological functions. EMBO J. 12, 3879-91. Szabowski A., Mass-Szabowski N., Andrecht S., Kolbus A., Schorpp-Kistner M., Fusenig N E., Angel P. (2000). c-Jun and junB antagonistically control cytokine-regulated mesenchymal-epidermal interaction in skin. Cell 103(5):745-55 Vasioukhin V., Degenstein L. Wise B., Fuchs E. (1999). The magic touch: Genome targeting in epidermal stem cells induced by tamoxifen application to mouse skin. Proc. Natl. Acad. Sci. 96: 8551-8556. Xia H., Mao Q., Paulson H. L., Davidson B. L. (2002) siRNA-mediated gene silencing in vitro and in vivo. Nat. Biotechnol. 20(10): 1006-10. Xia Y P., Li B., Hylton D., Detmar M., Yancopoulos G D., Rudge J S. (2003) Transgenic delivery of VEGF to mouse skin leads to an inflammatory condition resembling human psoriasis. Blood 102(1):161-8. Zenz R., Scheuch H., Martin P., Frank C., Eferl R., Kenner L., Sibilia M., Wagner E F. (2003). c-Jun regulates eyelid closure and skin tumor development trough EGFR signaling. Dev. Cell 4(6): 879-89. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The invention relates to the field of psoriasis. 2. Background Art Psoriasis, affecting about 2 % of the population, is one of the most common human skin disorders that affect skin and joints. It is characterized by complex alterations of various cell types. This includes epidermal hyperproliferation and altered differentiation, as well as angiogenesis and dilation of dermal blood vessels (Schön, 1999; Lebwohl, 2003). In addition, a mixed leukocytic infiltrate is seen. It is composed of activated T lymphocytes, neutrophiles within the dermis and epidermal microabscesses, lining macrophages, and an increased number of dermal mast cells. Cytokines including tumor necrosis factor-α (TNF-α), and interleukin-1 (IL-1), interferon-γ(INF-γ), IL-6, IL-8, vascular endothelial growth factor (VEGF) and transforming growth factor-α (TGF-α) are thought to mediate the psoriatic tissue alterations (Schön, 1999). For decades the ongoing controversy is whether psoriasis results from primary abnormalities in the epidermis or is immunologically based (Nickoloff et al., 2000). Although evidence is accumulating that it has an immunological basis others interpret psoriasis as a genetically determined, abnormal epithelial response pattern to infection and/or physicochemical skin insults. It has become clear that psoriatic skin is a hotbed of epidermal growth factors and inflammatory mediators. Supportive evidence of a key role for such mediators comes from patients who respond to immunsuppressive, anti-inflammatory, and antiproliferative therapies such as cyclosporine, methotrexate, tacrolimus, corticosteroids, and ultraviolet-light-activated psoralen. However, extensive efforts aimed at transgenically delivered inflammatory mediators or keratinocyte growth factors to the skin have not completely reproduced the psoriatic phenotype (Xia et al., 2003), which has thus far only been faithfully modeled in animals by transplanting psoriatic skin onto mice with severe combined immunodeficiency disease (SCID). So far no reported mouse model for psoriasis mimics all characteristics seen in psoriasis in humans, including psoriatic arthritis which is present in up to 40% of psoriasis patients. Since there is no naturally occurring animal skin disease mirroring both phenotype and immunopathogenesis of psoriasis, research into the pathogenesis of this common skin disorder has been severely hampered. Consequently, there is a need for an efficient and significant animal model for the study of psoriasis and for testing drug candidates effective in the treatment of this disorder. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>It was an object of the invention to provide an animal model for psoriasis, including psoriatic arthritis. In a first aspect, the invention relates to a mutant mouse which is deficient for c-Jun and JunB in the epidermis (jun Δep *,junB Δep *). In a preferred embodiment, the deficiency of c-Jun and JunB is caused by a deletion of c-Jun and JunB achieved by expression of a constitutively active or inducible recombination enzyme in the epidermis. In a further aspect, the invention relates to a mutant mouse, in which deletion of c-Jun and JunB can be specifically induced in the epidermis. In a preferred embodiment, deletion of c-Jun and JunB is achieved by expression of a constitutively active or inducible recombination enzyme in the epidermis. In a further aspect, the present invention relates to a mutant mouse which is deficient for c-Jun and JunB. In an additional aspect, the present invention relates to a method for producing a mutant mouse that is deficient for c-Jun and JunB in the epidermis comprising crossing (a) a transgenic mouse comprising a genetic construct containing the c-Jun and JunB genes flanked with recognition sites for a site-specific recombination enzyme with (b) a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis, wherein deletion of c-Jun and JunB is specifically induced in the epidermis. In one embodiment, the deficiency of c-Jun and JunB in the epidermis of the mutant mouse is induced by applying an anti-estrogen. The anti-estrogen is applied by intraperitoneal injection or by topical application. An example of a suitable anti-estrogen is tamoxifen. In a further aspect, the present invention relates to a method for producing a mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis comprising crossing (a) a transgenic mouse comprising a genetic construct containing the c-Jun and JunB genes flanked with recognition sites for a site specific recombination enzyme with (b) a transgenic mouse expressing a constitutively active or inducible recombinase in the epidermis. In one embodiment, the epidermal cells in the mutant mouse comprise a genetic construct comprising a keratinocyte-specific promoter operably linked to a nucleic acid molecule encoding Cre-recombinase, wherein said promoter is also operably linked to an estrogen receptor. In another embodiment of the invention, isolated keratinocytes may be derived from the mutant mouse that is either deficient for c-Jun and JunB in the epidermis or the mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis. Furthermore, the present invention is directed to the method of testing a drug to treat psoriasis in a human comprising administration of the drug to the mutant mouse that is deficient for c-Jun and JunB in the epidermis. Additionally, the present invention is directed to the method of testing a drug to treat psoriatic arthritis in a human comprising administration of the drug to the mutant mouse in which deletion of c-Jun and JunB can be specifically induced in the epidermis. | 20050121 | 20070724 | 20051201 | 94673.0 | 0 | SAJJADI, FEREYDOUN GHOTB | MOUSE MODEL FOR PSORIASIS AND PSORIATIC ARTHRITIS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,413 | ACCEPTED | Diagnosis system for variable valve controller | A control mode of an intake valve lift controller is changed between a low-speed mode and a high-speed mode. Based on the control mode, an ignition timing is adjusted. When a knocking is detected by a knock sensor after the control mode is changed from the low-speed mode to the high-speed mode, it is determined that the intake valve lift controller has a malfunction in which the intake valve lift controller is stuck in the low-speed mode. When a combustion stability is lowered to a predetermined level after the control mode is changed from the high-speed mode to the low-speed mode, it is determined that the intake valve lift controller has a malfunction in which the intake valve lift controller is stuck in the high-speed mode. | 1. A diagnosis system for a variable valve controller, the variable valve controller changing a valve profile of an intake valve and/or an exhaust valve from a control mode to another control mode based on a condition of an internal combustion engine, an ignition timing varied according to a change of the control mode, comprising: a knock detecting means for detecting a knocking of the internal combustion engine; and a malfunction diagnosis means for diagnosing whether a malfunction of the variable valve controller exists based on a detecting result by the knock detecting means when the control mode of the variable valve controller is changed. 2. The diagnosis system for a variable valve controller according to claim 1, wherein the malfunction diagnosis means determines that the variable valve controller has a malfunction when a knocking is detected by the knock detecting means after the control mode is changed from a low-speed mode in which a valve lift amount and/or a valve opening period is decreased to a high-speed mode in which the valve lift amount and/or the valve opening period is increased. 3. The diagnosis system for a variable valve controller according to claim 1, further comprising a cam angle sensor outputting a cam angle signal every predetermined cam angles, the malfunction diagnosis means diagnosing a malfunction of the variable valve controller for individual cylinders based on the cam angle signal and an output signal of the knock detecting means. 4. The diagnosis system for a variable valve controller according to claim 1, further comprising a combustion determine means for determining whether a combustion stability of the engine is over a predetermined value, the malfunction diagnosis means determines that the variable valve controller has a malfunction when the combustion stability is lowed to the predetermined value after the control mode is changed from a high-speed mode in which a valve lift amount and/or a valve opening period is increased to a low-speed mode in which the valve lift amount and/or the valve opening period is decreased. | CROSS REFERENCE TO RELATED APPLICATION This application is based on Japanese Patent Application No. 2004-015411 filed on Jan. 23, 2004, the disclosure of which is incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to a diagnosis system for a variable valve controller. The variable valve controller varies a valve profile of an intake valve and/or an exhaust valve. The valve profile represents a valve lift amount, a valve-opening period, a valve timing, and the like. BACKGROUND OF THE INVENTION It is known an engine for an automobile, which is provided with a variable valve controller varying a valve profile of an intake valve and/or an exhaust valve in order to improve the power, enhance the fuel economy, and reduce the exhaust emission of the engine. For instance, the variable valve controller changes the control mode of the valves between a low-speed mode and a high-speed mode. In the low-speed mode, a cam which drives the valve is turned into a low-speed cam to reduce the valve lift amount for obtaining a stable combustion. In high-speed mode, the cam is turned into a high-speed cam to increase the valve lift amount for enhancing the power of the engine. In such a variable valve controller, when the valve mode is not changed properly, the drivability of engine is deteriorated. For instance, when an actual control mode is still in the high-speed mode even though the control mode should be turned into the low-speed mode in a low-load driving condition, the combustion stability is deteriorated to cause the engine stalling. When the actual control mode is still in the low-speed mode even though the control mode should be turned into the high-speed mode in a high-load driving condition, the power of engine is reduced to deteriorate an acceleration thereof. Under such a situation, diagnosis systems for the variable valve controller have been proposed. Japanese Patent No. 2817055 shows a diagnosis system in which malfunctions of the variable valve controller are detected based on a deviation between an actual valve lift amount sensed by a lift sensor and a reference valve lift amount determined on the basis of the engine speed. Japanese Patent No. 2571629 shows a diagnosis system in which the valve-close timing is detected by a vibration sensor to be compared with a reference timing, by which malfunctions of the variable valve controller are detected. JP-4-159426 A shows a diagnosis system in which an intake pipe pressure derived from control conditions of the engine and variable valve controller is compared with an actual intake pipe pressure detected by an intake pipe pressure sensor, by which malfunctions of the variable valve controller are detected. In the diagnosis system shown in Japanese Patent No. 2817055, it is necessary to newly provide a lift sensor and to keep a mounting space for the lift sensor in a narrow space at vicinity of the valve, which makes the system complicated and increases a cost. In the diagnosis systems shown in Japanese Patent No. 2571629 and JP-4-159426 A, since the output signals from the pressure sensor and the lift sensor include noises, it is relatively hard to distinguish correct signals from incorrect signals. Therefore, it is difficult to diagnose the variable valve controller correctly. SUMMARY OF THE INVENTION The present invention is made in view of the foregoing matter and it is an object of the present invention to provide a diagnosis system for a variable valve controller which correctly diagnoses the variable valve controller, to simplify the structure thereof, and to reduce the cost thereof. According to the present invention, the diagnosis system includes the variable valve controller which changed a valve profile of an intake valve and/or an exhaust valve from a control mode to another control mode based on a condition of an internal combustion engine. An ignition timing is varied according to a change of the control mode. The diagnosis system includes a knock detecting means for detecting a knocking of the internal combustion engine, and a malfunction diagnosis means for diagnosing whether a malfunction of the variable valve controller exists based on a detecting result by the knock detecting means when the control mode of the variable valve controller is changed. BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings, in which like parts are designated by like reference numbers and in which: FIG. 1 is a schematic view of an engine control system according to an embodiment of the present invention; FIG. 2 is a front view of an intake valve lift controller; FIG. 3 is a chart showing a characteristic of the intake valve lift controller at both a low-speed mode and a high-speed mode; FIG. 4 is a chart showing a characteristic of the intake valve lift controller; FIG. 5 is a chart showing a ignition timing at both a low-speed mode and a high-speed mode of the intake valve lift controller; FIG. 6A is a time chart showing an output signal of a knock sensor in case that knocking is generating; FIG. 6B is a time chart showing an output signal of the knock sensor in case that no knocking is generated; FIG. 7 is a flowchart showing a basic ignition timing calculation routine; and FIG. 8 is a flowchart showing a malfunction diagnosis routine. DETAILED DESCRIPTION OF EMBODIMENT An embodiment of the present invention will be described hereinafter with reference to the drawings. The schematic construction of the entirety of an engine control system is illustrated in FIG. 1. An engine 11 is provided with an air cleaner 13 at the most upstream portion of an intake pipe 12 and with an air flow meter 14 for detecting an intake airflow on the downstream side of the air cleaner 13. On the downstream side of the air flow meter 14, there are disposed a throttle valve 15 having an opening adjusted by a DC motor or the like, and a throttle opening sensor 16 for detecting the throttle opening. On the downstream side of the throttle valve 15, moreover, there is disposed a surge tank 17, which is provided with an intake pipe pressure sensor 18 for detecting the intake pipe pressure. Moreover, the surge tank 17 is provided with an intake manifold 19 for introducing the intake air into the individual cylinders of the engine 11. Fuel injection valves 20 for individually injecting the fuel are attached to the vicinities of the intake ports of the intake manifold 19 of the individual cylinders. To the cylinder head of the engine 11, moreover, there are attached ignition plugs 21 for the individual cylinders, so that the air/fuel mixtures in the cylinders are ignited by the spark discharges of the individual ignition plugs 21. The engine 11 has an intake valve 32 and an exhaust valve 34, which are respectively provided with valve lift controllers 33 and 35. The intake valve 32 and the exhaust valve 34 may be further provided with variable valve timing controllers, which respectively varies the opening/closing timings of the valves 32, 34. The engine 11 has an exhaust pipe 22, which is provided with a catalyst 23 such as a three-way catalyst for reducing CO, HC, NOx and soon in the exhaust gas. On the upstream side of the catalyst 23, there is disposed an exhaust gas sensor 24 (e.g., an air/fuel ratio sensor or an oxygen sensor) for detecting the air/fuel ratio or a richness/leanness of the exhaust gas. To the cylinder block of the engine 11, moreover, there are attached a cooling water temperature sensor 25 for detecting the temperature of cooling water, and a crank angle sensor 26 for outputting a pulse signal each time the crankshaft of the engine 11 turns a predetermined crank angle. The crank angle and the engine speed are detected on the basis of the output signal of the crank angle sensor 26. A knock sensor 42 detecting a knocking of the engine is attached on the cylinder block of the engine 11. The outputs of the sensors are inputted to an electric control circuit, which is referred to as ECU 27 hereinafter. The ECU 27 is constructed mainly of a microcomputer including CPU 28, ROM 29, RAM 30, and backup RAM 31. The ECU 27 executes the various engine control programs stored in the ROM 29 thereby to control the fuel injection rate of the fuel injection valve 20 and the ignition timing of the ignition plug 21 in accordance with the engine running state. Referring to FIG. 2, the construction of the intake valve lift controller 33 is described hereinafter. As shown in FIG. 2, a camshaft 36 of the intake valve 32 is provided with a low-speed cam 37 and high-speed cam 38, which rotate integrally with the camshaft 36. Under the camshaft 36, a rocker shaft 39 is located. A rocker arm 40 is pivoted on the rocker shaft 39 in such a manner that the rocker arm 40 swing around the rocker shaft 39. An upper end of the intake valve 32 is attached to a tip portion of the rocker arm 40, so that the intake valve 32 is moved up/down by the rocker arm 40. The rocker arm 40 has a pushing portion for the high-speed cam 38 and a pushing portion for the low-speed cam 37. The low-speed cam 37 has a cam-profile in which a pushing amount to the rocker arm 40 is relatively small and a pushing period is also relatively short. On the other hand, the high-speed cam 38 has a cam-profile in which the pushing amount is relatively large and the pushing period is relatively long. The rocker arm 40 has a cam-switching mechanism 41 driven by an oil pressure. The cam-switching mechanism 41 switches the cam engaging with the rocker arm 40 between the high-speed cam 38 and the low-speed cam 37. When the control mode of the intake valve lift controller 33 is turned into the low-speed mode, the low-speed cam 37 is in contact with the rocker arm 40 to drive the intake valve 32. Thereby, as shown by a solid line in FIG. 3, the valve lift amount of intake valve 32 is decreased and the pushing period by the rocker arm 40 is decreased. Thus, the opening period of the intake valve 32 is decreased. On the other hand, when the control mode of the intake valve lift controller 33 is turned into the high-speed mode, the high-speed cam 38 is in contact with the rocker arm 40 to drive the intake valve 32. Thereby, as shown by a dotted line in FIG. 3, the valve lift amount of intake valve 32 is increased and the pushing period by the rocker arm 40 is increased. Thus, the opening period of the intake valve 32 is increased. The ECU 27 switches the control mode of the intake valve lift controller 33 between the low-speed mode and the high-speed mode according to the engine operation condition such as engine speed and engine load. An output torque of the engine 11 at the time of changing the control mode into the low-speed mode is equal to an output torque of the engine at the time of changing the control mode into the high-speed mode. Thus, torque variations are restricted when the control mode of the intake valve lift controller 33 is changed. Generally, when the control mode of the intake valve lift controller 33 is changed to vary the valve profile, which is a valve lift amount, a valve opening period, a valve closing timing and the like, the proper ignition timing is varied. Thus, the ECU 27 executes a basic-ignition-timing calculation routine shown in FIG. 7 to correct the ignition timing in case of changing the control mode of the intake valve lift controller 33. In high-speed mode, since the valve-opening period of the intake valve 32 is relatively long and valve-closing timing is retarded, it is necessary to advance the ignition timing to keep a stable combustion. Therefore, the ignition timing is advanced in the high-speed mode rather than in the low-speed mode at the same engine condition. As illustrated in FIG. 5, when the control mode is changed from the low-speed mode to the high-speed mode, the ignition timing is advanced. On the other hand, when the control mode is changed from the high-speed mode to the low-speed mode, the ignition timing is retarded. The ECU 27 executes a malfunction diagnosis routine shown in FIG. 8 to detect malfunctions of the intake valve lift controller 33. When the control mode of the intake valve lift controller 33 is changed from the low-speed mode to the high-speed mode, the ignition timing is advanced. When the control mode is still in the low-speed mode even if the computer outputs a signal to change the control mode from the low-speed mode to the high-speed mode, the advanced ignition timing exceeds the knock limit to cause a knocking as shown in FIG. 6A. When the ECU 27 receives a knocking signal from the knock sensor 42 in a predetermined period after the control mode is changed from the low-speed mode to the high-speed mode, it is determined that there are malfunctions in the intake valve lift controller 33. In order to distinguish the knocking due to the malfunctions of the intake valve lift controller 33 from the knocking due to the other reason, the diagnosis is executed only in the predetermined period. On the other hand, when the control mode of the intake valve lift controller 33 is changed from the high-speed mode to the low-speed mode, the ignition timing is retarded. When the control mode is still in the high-speed mode even if the computer outputs a signal to change the control mode from the high-speed mode to the low-speed mode, the ignition timing is retarded than a proper ignition timing of the high-speed mode, so that the combustion becomes unstable in low-load driving, such as in idling. The ECU determines that the intake valve lift controller 33 has malfunctions when the combustion stability has been under a predetermined level for a predetermined period in a low-load driving after the control mode is changed from the high-speed mode to the low-speed mode. Referring to FIG. 7 and FIG. 8, the program routine which the ECU 27 executes is described hereinafter. [Calculation of Basic Ignition Timing] A basic ignition timing calculation routine shown in FIG. 7 is executed is a predetermined interval while the engine is running. In step 101, it is determined whether the controls mode of the intake valve lift controller 33 is the high-speed mode. When it is Yes in step 101, the procedure proceeds to step 102 in which a basic ignition timing is calculated according to the present engine condition, such as an engine speed Ne and a required torque, by means of a basic ignition timing map for high-speed mode. Since the close timing of the intake valve 32 is retarded in the high-speed mode, it is necessary to advance the ignition timing to keep a stable combustion. The basic ignition timing map for the high-speed mode is formed to be more advanced than the map for the low-speed mode. When it is determined that the control mode of the intake valve lift controller 33 is the low-speed mode, the procedure proceeds to step 103 in which a basic ignition timing is calculated according to the present engine condition, such as an engine speed Ne and a required torque, by means of a basic ignition timing map for low-speed mode. As described above, the final ignition timing is determined according to the control mode. [Malfunctions Diagnosis] A malfunction diagnosis routine shown in FIG. 8, which is a diagnosis means, is executed is a predetermined interval while the engine is running. In step 201, it is determined whether the control mode of the intake valve lift controller 33 is the high-speed mode. When it is Yes in step 201, the procedure proceeds to step 202. In step 202, it is determined whether the previous control mode is the low-speed mode. When it is Yes in step 202, the procedure proceeds to step 203 in which a count number of a counter L is cleared to zero, the counter L measuring an elapsed time after the control mode is turned from the low-speed mode to the high-speed mode. Then, the procedure proceeds to step 206. When it is determined that the previous control mode is the high-speed mode in step 202, the procedure proceeds to step 204, in which the counter L is incremented. Then, the procedure proceeds to step 205 in which it is determined the count value of the counter L exceeds a predetermined value “A”. The count value of the counter L corresponds to an elapsed time after the control mode is turned into the high-speed mode. When the count value is less than the predetermined value “A”, the procedure proceeds to step 206. After processing step 205 or when it is No in step 205, the procedure proceeds to step 206, in which it is determined whether a knocking is detected by a knock sensor 42. When the number of knocking detection exceeds a predetermined number, it can be determined that a knocking is generated. The predetermine number can be altered according to a level of knocking. In a predetermined period after the control mode is turned from the low-speed mode to the high-speed mode, when it is determined that the knocking is generated in step 206, it is determined that the actual control mode is stuck in the low-speed mode even though the control mode is turned to high-speed mode. That is, it is determined that the advanced ignition timing based on the turning of the control mode exceeds the knock limit in the low-speed mode to generate the knocking. Then, the procedure proceeds to step 207 in which it is determined that the intake valve lift controller 33 has malfunctions so that a low-speed mode malfunction flag is set ON that represents the intake valve controller 33 is stuck in the low-speed mode. An alarm lump (not shown) or an alarm sign on a instrument panel is turned on to alert a driver, and malfunction data, such as malfunction codes, are stored in a nonvolatile memory such as a buck-up RAM 31 in the ECU 27 to end the routine. When it is determined that the knocking is not detected in step 206 in the predetermined period after the control mode is turned from the low-speed mode to the high speed mode, or when it is determined Yes in step 205 in the predetermined period, the procedure proceeds to step 208. In step 208, it is determined that the intake valve lift controller 33 has no malfunctions and the low-speed mode malfunction flag is turned OFF to end the routine. In step 201, when it is determined that the control mode of the intake valve lift controller 33 is the low-speed mode, the procedure proceeds to step 209 in which it is determined whether the engine is in a low-load condition such as idling where the engine speed is lower than a predetermined value and the engine load, such as an intake air volume, an intake pipe pressure, and the like, is lower than a predetermined value. When it is determined Yes in step 209, the procedure proceeds to step 210. In step 210, it is determined whether the combustion of the engine is stable based on whether an engine speed fluctuation ΔNe, a torque fluctuation ΔTr, and a control amount of idle speed control valve are lower than predetermined values respectively. When it is determined No in step 209 or when it is determined that the combustion condition is higher than a predetermined level in step 210, the procedure proceeds to step 211. In step 211, the count value of a counter H is cleared. The counter H counts a duration in which the engine load is low and the combustion condition is unstable. Then, the procedure proceeds to step 214 in which a high-speed mode malfunction flag is turned OFF to end the routine. When it is determined that the engine is running under the low-load condition in step 209 and the combustion condition is unstable in step 210, the procedure proceeds to step 212 in which the counter H is incremented. Then, the procedure proceeds to step 213 in which it is determined whether the count value of the counter H exceeds the predetermined value “B”. In step 213, when it is determined that a duration of low-load condition and unstable combustion of the engine exceeds a predetermined period, it is determined that the actual control mode is stuck in the high-speed mode even though the control mode is turned to the low-speed mode. That is, it is determined that the engine is running under more retarded ignition timing than a proper ignition timing in the high-speed mode, and that the combustion under the low-load is unstable. Then, the procedure proceeds to step 215 in which it is determined that the intake valve lift controller 33 has malfunctions and the high-speed mode malfunction flag is turned ON to end the routine. On the other hand, when it is determined that the duration of the low-load and unstable combustion does not reach to a predetermined period in step 213, the procedure proceeds to step 214 in which it is determined that the intake valve lift controller 33 has no malfunctions and the high-speed mode malfunction flag is turned OFF to end the routine. According to the present embodiment, when the intake valve lift controller 33 is stuck in the low-speed mode, a knocking is generated and it is determined that the intake valve lift controller 33 has malfunctions. The knocking is precisely detected by the knock sensor 42, so that the malfunctions of the intake valve lift controller 33 is also precisely detected. Thus, an additional lift sensor for the intake valve is not necessary, so that the construction of the system is simplified and cost is reduced. Based on output signals of cam angel sensor (FIGS. 6A, 6B) and output signals of the knock sensor 42, the malfunctions of the intake valve lift controller 33 can be diagnosed with respect to the individual cylinders. Since the combustion cylinder can be identified based on the output signal of the cam angle sensor, the knocking can be detected cylinder by cylinder to diagnose the intake valve lift controller 33. As mentioned above, the combustion of the engine becomes unstable when the intake valve lift controller 33 is stuck in the high-speed mode. According to the present invention, the malfunctions of the intake valve lift controller 33 are precisely detected when the combustion stability is lowed to a predetermined value or less. The present invention can be applied to not only an intake valve controller varying a valve lift or valve opening period but also a controller varying an intake valve opening timing and/or a valve profile of the exhaust valve, the valve profile representing at least one of a valve lift amount of the exhaust valve, a valve opening period of the exhaust valve, and a valve timing of the exhaust valve. In the aforementioned embodiment, the variable valve controller switches its valve profile between stages. The variable valve controller can switch its valve profile between three stages or more. The variable valve controller can vary its valve profile continuously. The variable valve controller is not limited to an oil-hydraulic driving controller, which can be replaced by an electromagnetic driving valve. | <SOH> BACKGROUND OF THE INVENTION <EOH>It is known an engine for an automobile, which is provided with a variable valve controller varying a valve profile of an intake valve and/or an exhaust valve in order to improve the power, enhance the fuel economy, and reduce the exhaust emission of the engine. For instance, the variable valve controller changes the control mode of the valves between a low-speed mode and a high-speed mode. In the low-speed mode, a cam which drives the valve is turned into a low-speed cam to reduce the valve lift amount for obtaining a stable combustion. In high-speed mode, the cam is turned into a high-speed cam to increase the valve lift amount for enhancing the power of the engine. In such a variable valve controller, when the valve mode is not changed properly, the drivability of engine is deteriorated. For instance, when an actual control mode is still in the high-speed mode even though the control mode should be turned into the low-speed mode in a low-load driving condition, the combustion stability is deteriorated to cause the engine stalling. When the actual control mode is still in the low-speed mode even though the control mode should be turned into the high-speed mode in a high-load driving condition, the power of engine is reduced to deteriorate an acceleration thereof. Under such a situation, diagnosis systems for the variable valve controller have been proposed. Japanese Patent No. 2817055 shows a diagnosis system in which malfunctions of the variable valve controller are detected based on a deviation between an actual valve lift amount sensed by a lift sensor and a reference valve lift amount determined on the basis of the engine speed. Japanese Patent No. 2571629 shows a diagnosis system in which the valve-close timing is detected by a vibration sensor to be compared with a reference timing, by which malfunctions of the variable valve controller are detected. JP-4-159426 A shows a diagnosis system in which an intake pipe pressure derived from control conditions of the engine and variable valve controller is compared with an actual intake pipe pressure detected by an intake pipe pressure sensor, by which malfunctions of the variable valve controller are detected. In the diagnosis system shown in Japanese Patent No. 2817055, it is necessary to newly provide a lift sensor and to keep a mounting space for the lift sensor in a narrow space at vicinity of the valve, which makes the system complicated and increases a cost. In the diagnosis systems shown in Japanese Patent No. 2571629 and JP-4-159426 A, since the output signals from the pressure sensor and the lift sensor include noises, it is relatively hard to distinguish correct signals from incorrect signals. Therefore, it is difficult to diagnose the variable valve controller correctly. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention is made in view of the foregoing matter and it is an object of the present invention to provide a diagnosis system for a variable valve controller which correctly diagnoses the variable valve controller, to simplify the structure thereof, and to reduce the cost thereof. According to the present invention, the diagnosis system includes the variable valve controller which changed a valve profile of an intake valve and/or an exhaust valve from a control mode to another control mode based on a condition of an internal combustion engine. An ignition timing is varied according to a change of the control mode. The diagnosis system includes a knock detecting means for detecting a knocking of the internal combustion engine, and a malfunction diagnosis means for diagnosing whether a malfunction of the variable valve controller exists based on a detecting result by the knock detecting means when the control mode of the variable valve controller is changed. | 20050121 | 20060404 | 20050728 | 59279.0 | 0 | VO, HIEU T | DIAGNOSIS SYSTEM FOR VARIABLE VALVE CONTROLLER | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,421 | ACCEPTED | System for protecting a portable computing device | The invention relates to a system for protecting a portable computing device wherein the system comprises a device housing adapted to protectively encase a portable computing device, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing. When the portable computing device is encased within the device housing, a user of the portable computing device can operate the portable computing device via the protectively hardened user input device and the protectively hardened display. The device housing may further comprise sealing elements, insulating elements, and shock-absorbing elements. | 1. A system for protecting a portable computing device, the system comprising: a device housing adapted to protectively encase the portable computing device to prevent exposure of the portable computing device to potentially harmful operational conditions, the portable computing device including at least one of a user input device and a display; a protectively hardened user input device in communication with said device housing; and a protectively hardened display in communication with said device housing, wherein said device housing allows a user of the portable computing device to operate the portable computing device via said protectively hardened user input device and said protectively hardened display. 2. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a laptop. 3. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a personal digital assistant. 4. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a handheld computer. 5. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a router. 6. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a switch. 7. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a telephone. 8. The system for protecting a portable computing device of claim 7, wherein the telephone is a cellular telephone. 9. The system for protecting a portable computing device of claim 1, wherein the portable computing device is a hub. 10. The system for protecting a portable computing device of claim 1, wherein the portable computing device is optical communications equipment. 11. The system for protecting a portable computing device of claim 1, wherein said protectively hardened user input device is a mouse. 12. The system for protecting a portable computing device of claim 1, wherein said protectively hardened user input device is a touch pad. 13. The system for protecting a portable computing device of claim 1, wherein said protectively hardened user input device is a joystick. 14. The system for protecting a portable computing device of claim 1, wherein said device housing further comprises a sealing element. 15. The system for protecting a portable computing device of claim 14, wherein said sealing element comprises a moisture seal. 16. The system for protecting a portable computing device of claim 14, wherein said sealing element comprises a debris seal. 17. The system for protecting a portable computing device of claim 14, wherein said sealing element comprises a vapor seal. 18. The system for protecting a portable computing device of claim 14, wherein said sealing element comprises a electromagnetic seal. 19. The system for protecting a portable computing device of claim 1, wherein said device housing further comprises an insulating element. 20. The system for protecting a portable computing device of claim 19, wherein said insulating element comprises thermal insulation. 21. The system for protecting a portable computing device of claim 19, wherein said insulating element comprises an electromagnetic interference shield. 22. The system for protecting a portable computing device of claim 19, wherein said insulating element comprises a radio frequency interference shield. 23. The system for protecting a portable computing device of claim 1, wherein said device housing further comprises a shock-absorbing element. 24. The system for protecting a portable computing device of claim 1, wherein at least a portion of said device housing is formed of a plastic material. 25. The system for protecting a portable computing device of claim 1, wherein at least a portion of said device housing is formed of a metal material. 26. The system for protecting a portable computing device of claim 1, wherein at least a portion of said device housing is formed of Kevlar or carbon fiber. 27. The system for protecting a portable computing device of claim 1, wherein, when the portable computing device includes an upper housing for housing a display, a lower housing for housing a user input device, and a hinge element for pivotally connecting the upper housing to the lower housing and enabling the portable computing device to rotate around the hinge element into an open position and a closed position, said device housing further comprising a recessed portion for protectively encasing the portable computing device when the portable computing device is in the closed position. 28. The system for protecting a portable computing device of claim 11, wherein said device housing allows a user of the portable computing device to operate the portable computing device via said protectively hardened user input device and said protectively hardened display when the portable computing device is in the closed position and is protectively encased within said recessed portion of said device housing. 29. The system for protecting a portable computing device of claim 1, wherein the portable computing device is electronically coupled to said device housing. 30. The system for protecting a portable computing device of claim 1, wherein said protectively hardened user input device is mounted on said device housing. 31. The system for protecting a portable computing device of claim 1, wherein said protectively hardened display is mounted on said device housing. 32. The system for protecting a portable computing device of claim 1, wherein said device housing allows a user of the portable computing device to operate the portable computing device via said protectively hardened user input device and said protectively hardened display without exposing the portable computing device to potentially harmful operational conditions of use. 33. A system for protecting a communications device having at least one communications port, the system comprising: a device housing adapted to protectively encase the communications device, said device housing having at least one interface corresponding to the at least one communications port of the communications device; a protectively hardened user input device in communication with said device housing; and a protectively hardened display in communication with said device housing. 34. The system for protecting a communications device of claim 33, wherein said communications device is a switch. 35. The system for protecting a communications device of claim 33, wherein said communications device is a router. 36. The system for protecting a communications device of claim 33, wherein said communications device is a hub. 37. The system for protecting a communications device of claim 33, wherein said at least one interface of said device housing enables at least one of configuration, control, and management of the communications device via said protectively hardened user input device. 38. The system for protecting a portable computing device of claim 33, wherein said communications device is an optical communications device. | BACKGROUND OF THE INVENTION The present invention relates generally to a system for protecting a portable computing device. More specifically, the present invention relates to a system for protecting a portable computing device which allows use of the portable computing device without exposing any of the integrated components of the portable computing device to potentially harmful operational conditions. Since the advent of personal computers, manufacturers and industrial users have continually developed faster, smaller and more versatile machines, including portable computers that are dedicated to perform a specific function such as word processing, data collection or item identification. Alternatively, portable computing devices may be all purpose computing machines capable of running a variety of types of software programs. These portable computing devices, such as personal computers, may interact with a variety of portable and stationary peripheral input/output devices such as printers, light pens, image scanners, video scanners, etc. Moreover, these computers may have an electric power cord for receiving power from a standard electric outlet, as well as a battery pack for powering the unit when an electric outlet is unavailable or is inconvenient. The portability and versatility of portable computers, in combination with the ever decreasing size and weight of these machines, has attracted a significant number of users, with the number of users expected to dramatically increase in the near term. The design and versatility of portable computers have progressed significantly, and in addition to laptop computers, personal digital assistants (PDAs), tablet computers, and other handheld computers have become popular. Laptop computers generally include an upper housing for a display, a lower housing for a keyboard, and a pivot for pivotally attaching the upper housing to the lower housing. Such construction is often referred to as “clam shell” construction. Generally, the upper housing and display are rotated away from the keyboard when the user wishes to utilize the portable computer, and are similarly rotated toward the keyboard when the palm top or portable computer is not in use. The cost of these versatile portable computers continues to decrease as they are becoming increasingly common in all areas of business and personal life, and the manufacturers enjoy savings due to the economies of scale associated with mass production. Alternatively, many types of portable computers are designed to fill a specific need, for example, the need for a portable computer that can withstand a rugged environment. While devices of this type offer added convenience to the end user, and are manufactured of heavier materials, these devices are generally more application specific and thus do not enjoy the economies of scale associated with mass production. Thus, these “ruggedized” or “hardened” portable computers cost significantly more than a typical portable computer. In cases wherein the computer may be dropped, exposed to high amounts of moisture, dirt, extreme temperatures, etc., a typical portable computer may be irreparably damaged. Therefore, users are forced to continue to purchase ruggedized computers at an increased cost to prevent having to frequently repair or replace their typical portable computers due to their operational conditions. Also, ruggedizing, also known as “hardening”, to extend the range of operating conditions, such as temperature, vibration, and shock, that can be sustained by the device is very expensive, especially considering the testing and certifications that must be performed for government and other compliance applications. Moreover, computer technology is one of the most rapidly developing technological fields in industry today. A top of the line portable computer is likely to be outdated as soon as within a year from its release in the marketplace, and may also be eventually unusable due to the system requirements of newer software applications. Similarly, interactive and multimedia applications, which are becoming increasingly popular, require significantly higher system performance than traditional word processing applications. Thus, users are forced to frequently replace their existing computers to maintain a high level of technological capability. With the increased cost of ruggedized portable computers as compared to typical portable computers, frequent upgrading and replacement of portable computer can be quite costly and is not desirable. In some instances, such as government specification applications, replacement might not be possible due to the length of time required for the applicable certification testing. However, the ever increasing overhaul required for typical operating systems and application software require that hardware be upgraded frequently. In an attempt to overcome this problem, those skilled in the art have attempted to enable the use of typical portable computers in rugged environments by designing protective cases of housings which can protect the portable computer during transport, etc. Various U.S. patents relate to this technology such as U.S. Pat. No. 6,297,236 issued to Seok, U.S. Pat. No. 5,632,373 issued to Kumar et al., and U.S. Pat. No. 5,214,574 issued to Chang. However, these protective cases still do not enable a user to operate a typical portable computer in harsh and rugged environments. In particular, the protective cases only protect the portable computer from environmental conditions while the computer is not being operatied, for example, during transport. When the portable computer is being operated, the computer and its peripherals are exposed to the environment. Thus, if the portable computer is being operated in the rain, for example, the protective cover will protect the portable computer from the rain until the computer is opened and operatied, at which time the computer will be unprotected. While protective cases, membranes, and the like are utilized for other types of electronic devices while still allowing use of the device, for example, a waterproof case for a non-waterproof camera, none of the existing protective cases offer protection for a device as complex or demanding as a portable computer or allow for the use of peripherals, such as a keyboard and a display, as is preferred for successful operation of a portable computer. SUMMARY OF INVENTION A preferred embodiment of the invention relates to a system for protecting a portable computing device, the system comprising a device housing adapted to protectively encase the portable computing device to prevent exposure of the portable computing device to potentially harmful operational conditions, the portable computing device including at least one of a user input device and a display, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing, wherein the device housing allows a user of the portable computing device to operate the portable computing device via the protectively hardened user input device and the protectively hardened display. In addition, a preferred embodiment of the invention relates to a system for protecting a communications device having at least one communications port, the system comprising a device housing adapted to protectively encase the communications device, the device housing having at least one interface corresponding to the at least one communications port of the communications device, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing. The protectively hardened input device may be one of an interface, a keyboard, a mouse, a touch pad, or a joystick, for example. Accordingly, the at least one interface of the device housing may enable at least one of configuration, control, and management of the communications device or portable computing device via the protectively hardened user input device. Moreover, the device housing may further comprise a sealing element, such as a moisture seal, a debris seal, a vapor seal, a electromagnetic seal, or an insulating element, such as thermal insulation, an electromagnetic interference (EMI) shield, or a radio frequency interference (RFI) shield. The device housing may also include a shock-absorbing element to attenuate any vibrations. In additional, the device housing may be formed of a plastic material, a metal material, or any other suitable material. Moreover, if the portable computing device or communications device includes an upper housing for housing a display, a lower housing for housing a user input device, and a hinge element for pivotally connecting the upper housing to the lower housing and enabling the portable computing device or communications device to rotate around the hinge element into an open position and a closed position, the device housing further comprising a recessed portion for protectively encasing the portable computing device or communications device when the portable computing device or communications device is in the closed position. Accordingly, the device housing may allow a user of the portable computing device or communications device to operate the portable computing device or communications device via the protectively hardened user input device and the protectively hardened display when the portable computing device or communications device is in the closed position and is protectively encased within the recessed portion of the device housing. The portable computing device or communications device may be communicatively coupled to the device housing, using electrical, optical, electromagnetic, or other communication mechanisms. Furthermore, the protectively hardened user input device and the protectively hardened display may be mounted on the device housing. Accordingly, the device housing may allow a user of the portable computing device or communications device to operate the portable computing device or communications device via the protectively hardened user input device and the protectively hardened display without exposing the portable computing device or communications device to potentially harmful operational conditions of use. The invention may be applied to and used in conjunction with all types of portable computing devices or communications devices. Some examples of acceptable portable computing devices include laptops, personal digital assistants, handheld computers, routers, switches, hubs, telephones, cellular and other mobile telephones, or optical communications equipment. Some examples of such communications devices include routers, hubs, or switches. Examples of optical communications equipment include optical multiplexers and de-multiplexers. These and other features, objects and advantages of the present invention will be in part apparent to those skilled in art and in part pointed out hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A-1C are perspective views of an aspect of a preferred embodiment of the invention. FIGS. 2A-2D are perspective views of an aspect of a preferred embodiment of the invention. FIGS. 3A-3D are perspective views of an aspect of a preferred embodiment of the invention. FIG. 4A-4C are perspective views of an aspect of a preferred embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION The following description is of an embodiment presently contemplated for practicing the invention. This description is not to be taken in a limiting sense but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be ascertained with reference to the issued claims. In the description of the invention that follows, like numerals or reference designators will be used to refer to like parts or elements throughout. Each system or system component described herein or shown on the enclosed figures has a three digit reference numeral. The last two digits of each reference numeral are consistent throughout for related systems or system components. Unless specifically noted to the contrary, every system or system component described herein has the same general characteristics and features of the other related systems or system components. For example, device housing 140 in FIGS. 1A-1C is related to and has the same general characteristics and features of device housing 240 in FIGS. 2A-2D, device housing 340 in FIGS. 3A-3D, and device housing 440 in FIGS. 4A-4C. The invention relates generally to a system for protecting a portable computing device, or a communications device, the system comprising a device housing adapted to protectively encase the portable computing device or communications device to prevent exposure of the portable computing device or communications device to potentially harmful operational conditions, the portable computing device or communications device including at least one of a user input device and a display, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing, wherein the device housing allows a user of the portable computing device or communications device to operate the portable computing device via the protectively hardened user input device and the protectively hardened display. In this manner, the portable computing device or communications device retains functionality while exposure of the portable computing device or communications device to potentially harmful operational condition is prevented. In addition, a preferred embodiment of the invention relates to a system for protecting a communications device having at least one communications port, the system comprising a device housing adapted to protectively encase the communications device, the device housing having at least one interface corresponding to the at least one communications port of the communications device, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing. Referring now to FIGS. 1A-1C, a preferred embodiment of the invention relates to a system 100 for protecting a portable computing device 500. Portable computing device 500 may be any type of portable computing device or communications device. For example, portable computing device 500 may be a portable computer, a laptop, a personal digital assistant (PDA), a handheld computer, a router, a switch, a hub, a telephone, or a cellular telephone. System 100 includes device housing 140, which is adapted to protectively encase portable computing device 500. Housing 140 includes a rugged outer shell 120, a recessed portion 115, and a lid portion 110. Outer shell 120 is preferably formed integrally with housing 140, as is shown in the figures. Moreover, outer shell 120 is constructed of a rugged and strong material, for example, plastic or metal, which is resistant to breakage, etc. Moreover, each of the components described herein as being “rugged” or “protectively hardened” include outer coverings similar to outer shell 120. Recessed portion 115 may be formed in any position on housing 140, for example, on the top, as is exemplified in FIGS. 1A-1C, on the side, as is exemplified in FIGS. 2A-2D, or on the front, as is exemplified in FIG. 3A-3D. Moreover, recessed portion 115 is sized to fit portable computing device 500, regardless of what type of portable computing device is received. For example, recessed portion 115 will be relatively small if portable computing device 500 is a smaller portable computing device such as a PDA or a handheld computer. However, as is exemplified by the figures, portable computing device 500 may be a laptop computer, with recessed portion 115 being large enough to receive the laptop computer. When portable computing device 500 is a laptop computer or any type of portable computing device that includes an upper housing for housing a display, a lower housing for housing a keyboard, and a hinge element for pivotally connecting the upper housing to the lower housing and enabling the portable computing device to rotate around the hinge element into an open position and a closed position, recessed portion 115 of housing 140 may be sized to receive portable computing device 500 in the closed position. In addition, it is preferable that portable computing device 500 fit snuggly within recessed portion 115 to prevent motion of portable computing device 500 relative to housing 140 while portable computing device 500 is positioned within recessed portion 115. Thus, padding or any other suitable material may be used in recessed portion 115 to ensure a snug fit. This material can be an inexpensive custom foam designed for the particular portable computing device being used. For example, this material may generally resemble the foam liner typically found in laptop computer carrying cases. Each different model of portable computing device may have a custom liner of a size and shape appropriate to secure that particular portable computing device within the recessed portion. In addition, when positioned within recessed portion 115, portable computing device 500 is in communication with, and electronically coupled to, housing 140 via docking elements 130. The positioning of docking elements 130 on housing 140 will vary depending on the size and type of portable computing device used. For example, when portable computing device 500 is a laptop computer, docking elements 130 will be space further apart to correspond to the larger size of a laptop computer. In the alternative, if portable computing device 500 is a PDA or a handheld computer, docking elements 130 will be closer together to correspond to the smaller size of the PDA or handheld computer. Housing 140 may include a plurality of sets of docking elements 130 such that different type of portable computing devices 500 may be used without making any significant changes to housing 140. In the alternative, housing 140 may be designed specifically to receive only one type of portable computing device, such as a laptop computer. In this case, docking elements 130 can be customized to receive that type of portable computing device. Docking elements 130 may consist of a variety of individuals docking elements for the various outputs of portable computing device 500. For example, docking elements 130 may include elements for allowing communication for a variety of communication elements such as a telephone connection to facilitate use of a modem and an Ethernet connection to facilitate use of the network connectivity of portable computing device 500. In addition, docking elements 130 may include elements for enabling communication between portable computing device 500 and any of a variety of peripherals, for example, a mouse, a keyboard, a display, speakers, a printer, additional storage or encrypted storage and communication systems, a network such as Ethernet, an antenna for wireless communication, and an authentication key or biometric access key. Furthermore, docking elements 130 may also include connections to a power source, USB ports, firewire ports, infrared connections, and any other types of connections and ports available on portable computing device 500. Thus, docking elements 130 may include many different types of docking elements include electrical power, serial ports, printer ports, USB and firewire ports, printer ports, etc. Accordingly, portable computing device 500 can achieve its same connectivity and functionality by docking with docking elements 130 that it could achieve if used separately from housing 140. Docking elements are not limited to connectors, but may include pigtails to allow a number of different types of portable computing devices to be connected, as well as power conditioning equipment such as filters and regulators, or custom interface modules or docking stations. When portable computing device 500 is positioned within recessed portion 115 of housing 140, rugged lid portion 110 is closed over portable computing device 500, thereby completely encasing portable computing device 500 within recessed portion 115. As is exemplified in FIGS. 1A-1C, lid portion 110 may be attached to housing 140 with a plurality of hinges 125. Hinges 125 are merely an example of how lid portion 110 may be mounted on housing 140. Other possible means of mounting lid portion 110 on housing 140 include a set of screws for attaching lid portion 110 to housing 140, sliding lid portion 110 relative to housing 140, and forming lid portion 110 integrally with housing 140 in a manner that allows portable computing device 500 to be encased with housing 140. When lid portion 110 is closed over recessed portion 115 and portable computing device 500, a sealing element 160 is compressed between lid portion 110 and housing 140, thereby forming a seal between housing 140 and lid portion 110. Sealing element 160 can be mounted on or formed integrally with either lid portion 110 or housing 140, or may be a separate component. For example, sealing element 160 may be a gasket type element affixed to either lid portion 110 or housing 140. As exemplified in the figures, sealing element 110 is preferably affixed to lid portion 110. The seal formed between lid portion 110 and housing 140 can consist of one or more of a moisture seal, a debris seal, and a vapor seal, for example. A moisture seal is a seal that prevents liquids, for example, water, from entering recessed portion 115 and coming into contact with portable computing device 500. The moisture seal thus prevents the portable computing device from being exposed to external moisture such as rain, chemicals, drinks, etc. A debris seal is a seal that prevents debris, for example, dirt and sand, from entering recessed portion 115 and coming into contact with portable computing device 500. The debris seal thus prevents the portable computing device from being exposed to external debris such as dust, etc. A vapor seal is a seal that prevents vapors, for example, gases, from entering recessed portion 115 and coming into contact with portable computing device 500. The vapor seal accordingly prevents the portable computing device from being exposed to external vapors such as potentially harmful gases, water vapors, etc. Thus, when portable computing device 500 is encased within housing 140, sealing element 160 can prevent damage to portable computing device 500 when portable computing device 500 is used, for example, outside during a hurricane or dust storm. Various sealing functions, such as those described above, may be accomplished by either a single sealing element 160 or by multiple sealing elements 160 used in combination. Additionally, an electromagnetic interference (EMI) shield or radio frequency interference (RFI) shield can be used to prevent the transmission of electromagnetic energy. Housing 140 and lid portion 110 may also include one or more of insulating elements 170. Insulating elements 170, which are formed of an insulating material such as foam or the like, are preferably positioned in and around recessed portion 115 of housing 140 and lid portion 110. For example, insulating elements 170 may be positioned on the inner side of lid portion 110 facing recessed portion 115 and on the bottom and sides of recessed portion 115. Thus, when portable computing device 500 is encased within housing 140, insulating elements 170 effectively surround portable computing device 500. In the alternative, insulating elements 170 may be formed integrally within housing 140. For example, housing 140 and lid portion 110 may be constructed of a material that is naturally insulating. Insulating elements 170 insulate portable computing device 500 from external conditions that may be harmful to portable computing device 500. For example, insulating elements 170 may provide thermal insulation to protect portable computing device 500 from extreme external temperatures, for example, extreme heat or cold. Thus, if portable computing device 500 is encased within housing 140 and is used in extremely cold conditions, for example, in the arctic, insulating elements 170 insulate portable computing device 500 and prevent portable computing device 500 from freezing. Additionally, temperature compensating devices such as solid-state heat pumps or heat-sinking (conducting) shock-absorbing foam, can be incorporated to maintain the portable computing device within its operational range. Insulating elements 170 may also function as shock-absorbing elements. In this case, insulating elements 170 protect portable computing device 500 from external vibrations that may be harmful to portable computing device 500. For example, insulating elements 170 can absorb external vibrations that impact housing 140. Thus, if housing 140 is subjected to potentially harmful levels of vibration, for example, being dropped or being used in a vehicle in motion, insulating elements 170 protect portable computing device 500 from those vibrations. Therefore, if portable computing device 500 is encased within housing 140 and is used in a manner that would normally expose portable computing device 500 to potentially harmful shocks and vibrations, for example, in a moving vehicle, insulating elements 170 absorb those vibrations and prevent the vibrations from damaging portable computing device 500. When portable computing device 500 is encased within housing 140, portable computing device is in communication with one or more peripherals, for example, a rugged display 105 and a rugged user input device 135. Other peripherals may include a mouse, a printer, a network, a phone jack, etc. This communication may be facilitated by cables 145. One end of cables 145 are connected to one or more peripherals. The other end of cable 145 is connected to housing 140. The end of cable 145 connected to housing 140 are in communication with portable computing device 500 via docking elements 130, as described above. Thus, cables 145 may be any type of cable adapted for use with a portable computing device such as USB cables, telephone cables, network cables, firewire cables, and serial cables. As an alternative to cables 145, housing 140 or computer 500 may have wireless capability, thereby being in communication with one or more peripherals wirelessly. The rugged peripherals, for example, rugged display 105 and rugged user input device 135, are designed for use in harsh and potentially harmful environments. As with housing 140, each of the peripherals preferably includes an outer shell similar to outer shell 120 of housing 140. In addition, each of the rugged peripherals should be resistant to external conditions of concern. For example, if system 100 is used in a wet environment, for example, during a hurricane, and sealing element 160 includes a moisture seal, it is preferable for each of the rugged peripherals to also be resistant to moisture. Accordingly, the rugged user input device 135 would be impervious to moisture and would be fully functional in a wet environment. Therefore, when portable computing device 500 is encased within housing 140 as described above, portable computing device 500 may be operated using rugged peripherals in communication with portable computing device 145, such as rugged user input device 135 and rugged display 105. Accordingly, portable computing device 500 may be used via the rugged peripherals in unfavorable and potentially damaging conditions without exposing portable computing device 500 to those conditions. The preferred embodiments of the invention shown in FIGS. 2A-2D, 3A-3D, and 4A-4C include slight variations from the preferred embodiment shown in FIGS. 1A-1C in two ways. First, as is described above, the recessed portion of the housing may be located in different positions on the housing. Second, the rugged peripherals, such as a rugged user input device and a rugged display, may be mounted onto the housing. FIGS. 2A-2D exemplify a system 200 for protecting portable computing device 500 wherein system 200 includes a device housing 240 adapted to protectively encase portable computing device 500 to prevent exposure of portable computing device 500 to potentially harmful operational conditions. As is described above, portable computing device 500 may include a user input device and a display, for example, a laptop computer. However, portable computing device 500 may be any type of portable computing device, for example, a PDA or a handheld computer. Housing 240 includes a rugged outer shell 220, a recessed portion 215, and a lid portion 210. As is shown in the figures, recessed portion 215 may be formed on the side of housing 240. Thus, portable computing device 500 can be inserted into recessed portion 215 from the side of housing 140, and docked with housing 240 as described above with reference to docking elements 130 shown in FIGS. 1A-1C. Thus, portable computing device 500 is in communication with docking elements of housing 240. When portable computing device 500 is positioned within recessed portion 215 of housing 240, rugged lid portion 210 is closed over portable computing device 500, thereby completely encasing portable computing device 500 within recessed portion 215. Lid portion 210 may be attached to housing 240 with a plurality of hinges 225 or by any other suitable means. When lid portion 210 is closed over recessed portion 215 and portable computing device 500, a sealing element 260 is compressed between lid portion 210 and housing 240, thereby forming a seal between housing 240 and lid portion 210. As described above, the seal formed between lid portion 210 and housing 240 can consist of one or more of a moisture seal, a debris seal, and a vapor seal, for example. Thus, when portable computing device 500 is encased within housing 240, sealing element 260 can prevent damage to portable computing device 500 when portable computing device 500 is used, for example, outside during a hurricane or dust storm. Housing 240 and lid portion 210 may also include one or more of insulating elements 270. Insulating elements 270, which are formed of an insulating material such as foam or the like, are preferably positioned in and around recessed portion 215 of housing 240 and lid portion 210. For example, insulating elements 270 may be positioned on the inner side of lid portion 210 facing recessed portion 215 and on the top, bottom, and sides of recessed portion 215. Thus, when portable computing device 500 is encased within housing 240, insulating elements 270 effectively surround portable computing device 500. In the alternative, insulating elements 270 may be formed integrally within housing 240. For example, housing 240 and lid portion 210 may be constructed of a material that is naturally insulating. Insulating elements 270 insulate portable computing device 500 from external conditions that may be harmful to portable computing device 500. For example, insulating elements 270 may provide thermal insulation to protect portable computing device 500 from extreme external temperatures, for example, extreme heat or cold. Thus, if portable computing device 500 is encased within housing 240 and is used in extremely cold conditions, for example, in the arctic, insulating elements 270 insulate portable computing device 500 and prevent portable computing device 500 from freezing. Insulating elements 270 may also function as shock-absorbing elements. In this case, insulating elements 270 protect portable computing device 500 from external vibrations that may be harmful to portable computing device 500. For example, insulating elements 270 can absorb external vibrations that impact housing 240. Thus, if housing 240 is subjected to potentially harmful levels of vibration, for example, being dropped or being used in a vehicle in motion, insulating elements 270 protect portable computing device 500 from those vibrations. Therefore, if portable computing device 500 is encased within housing 240 and is used in a manner that would normally expose portable computing device 500 to potentially harmful shocks and vibrations, for example, in a moving vehicle, insulating elements 270 absorb those vibrations and prevent the vibrations from damaging portable computing device 500. When portable computing device 500 is encased within housing 240, portable computing device is in communication with one or more peripherals, for example, a rugged display 205 and a rugged user input device 235. Other peripherals may include a mouse, a printer, a network, a phone jack, etc. As is shown in FIGS. 2A-2D, these rugged peripherals may be mounted directly on, or be formed integrally with, housing 240. For example, rugged user input device 235 and rugged display 205 may be mounted directly on housing 240. The rugged peripherals, for example, rugged display 205 and rugged user input device 235, are designed for use in harsh and potentially harmful environments. As with housing 240, each of the peripherals preferably includes an outer shell similar to outer shell 220 of housing 240. In addition, each of the rugged peripherals should be resistant to external conditions of concern. For example, if system 200 is used in a wet environment, for example, during a hurricane, and sealing element 260 includes a moisture seal, it is preferable for each of the rugged peripherals to also be resistant to moisture. Therefore, when portable computing device 500 is encased within housing 240 as described above, portable computing device 500 may be operated using rugged peripherals mounted on or formed integrally with housing 240, such as rugged user input device 235 and rugged display 205. Accordingly, portable computing device 500 may be used via the rugged peripherals in unfavorable and potentially damaging conditions without exposing portable computing device 500 to those conditions. FIGS. 3A-3D exemplify a system 300 similar to system 200 shown in FIGS. 2A-2D with the exception that a recessed portion 315 is positioned on the front of housing 340. Thus, system 300 is a system for protecting portable computing device 500 wherein system 300 includes a device housing 340 adapted to protectively encase portable computing device 500 to prevent exposure of portable computing device 500 to potentially harmful operational conditions. Housing 340 includes a rugged outer shell 320, a recessed portion 315, and a lid portion 310. As is shown in the figures, recessed portion 315 may be formed on the front of housing 340. Thus, portable computing device 500 can be inserted into recessed portion 315 from the front of housing 340, and docked with housing 340 as described above with reference to docking elements 130 shown in FIGS. 1A-1C. When portable computing device 500 is positioned within recessed portion 315 of housing 340, rugged lid portion 310 may be closed over portable computing device 500, thereby completely encasing portable computing device 500 within recessed portion 315. Lid portion 310 may be attached to housing 340 with a plurality of hinges 325 or by any other suitable means. When lid portion 310 is closed over recessed portion 315 and portable computing device 500, a sealing element 360 is compressed between lid portion 310 and housing 340, thereby forming a seal between housing 340 and lid portion 310. As described above, the seal formed between lid portion 310 and housing 340 can consist of one or more of a moisture seal, a debris seal, and a vapor seal, for example. Thus, when portable computing device 500 is encased within housing 340, sealing element 360 can prevent damage to portable computing device 500 when portable computing device 500 is used, for example, outside during a hurricane or dust storm. Housing 340 and lid portion 310 may also include one or more of insulating elements 370. Insulating elements 370, which are formed of an insulating material such as foam or the like, are preferably positioned in and around recessed portion 315 of housing 340 and lid portion 310. For example, insulating elements 370 may be positioned on the inner side of lid portion 310 facing recessed portion 315 and on the top, bottom, and sides of recessed portion 315. Thus, when portable computing device 500 is encased within housing 340, insulating elements 370 effectively surround portable computing device 500. In the alternative, insulating elements 370 may be formed integrally within housing 340. For example, housing 340 and lid portion 310 may be constructed of a material that is naturally insulating. Insulating elements 370 insulate portable computing device 500 from external conditions that may be harmful to portable computing device 500. For example, insulating elements 370 may provide thermal insulation to protect portable computing device 500 from extreme external temperatures, for example, extreme heat or cold. Thus, if portable computing device 500 is encased within housing 340 and is used in extremely cold conditions, for example, in the arctic, insulating elements 370 insulate portable computing device 500 and prevent portable computing device 500 from freezing. Insulating elements 370 may also function as shock-absorbing elements. In this case, insulating elements 370 protect portable computing device 500 from external vibrations that may be harmful to portable computing device 500. For example, insulating elements 370 can absorb external vibrations that impact housing 340. Thus, if housing 340 is subjected to potentially harmful levels of vibration, for example, being dropped or being used in a vehicle in motion, insulating elements 370 protect portable computing device 500 from those vibrations. Therefore, if portable computing device 500 is encased within housing 340 and is used in a manner that would normally expose portable computing device 500 to potentially harmful shocks and vibrations, for example, in a moving vehicle, insulating elements 370 absorb those vibrations and prevent the vibrations from damaging portable computing device 500. When portable computing device 500 is encased within housing 340, portable computing device is in communication with one or more peripherals, for example, a rugged display 305 and a rugged user input device 335. Other peripherals may include a mouse, a printer, a network, a phone jack, etc. As is shown in FIGS. 3A-3D, these rugged peripherals may be mounted directly on, or be formed integrally with, housing 340. For example, rugged user input device 335 and rugged display 305 may be mounted directly on housing 340. The rugged peripherals, for example, rugged display 305 and rugged user input device 335, are designed for use in harsh and potentially harmful environments. As with housing 340, each of the peripherals preferably includes an outer shell similar to outer shell 320 of housing 340. In addition, each of the rugged peripherals should be resistant to external conditions of concern. For example, if system 300 is used in a wet environment, for example, during a hurricane, and sealing element 360 includes a moisture seal, it is preferable for each of the rugged peripherals to also be resistant to moisture. Therefore, when portable computing device 500 is encased within housing 340 as described above, portable computing device 500 may be operated using rugged peripherals mounted on or formed integrally with housing 340, such as rugged user input device 335 and rugged display 305. Accordingly, portable computing device 500 may be used via the rugged peripherals in unfavorable and potentially damaging conditions without exposing portable computing device 500 to those conditions. FIGS. 4A-4C also exemplify a system 400 similar to system 200 shown in FIGS. 2A-2D with the exception that a recessed portion 415 is positioned on the top of housing 440. Thus, system 400 is a system for protecting portable computing device 500 wherein system 400 includes a device housing 440 adapted to protectively encase portable computing device 500 to prevent exposure of portable computing device 500 to potentially harmful operational conditions. Housing 440 includes a rugged outer shell 420, a recessed portion 415, and a lid portion 410. As is shown in the figures, recessed portion 415 may be formed on the front of housing 440. Thus, portable computing device 500 can be inserted into recessed portion 415 from the front of housing 440, and docked with docking elements 430 as described above with reference to docking elements 130 shown in FIGS. 1A-1C. When portable computing device 500 is positioned within recessed portion 415 of housing 440, rugged lid portion 410 may be closed over portable computing device 500, thereby completely encasing portable computing device 500 within recessed portion 415. Lid portion 410 may be attached to housing 440 with a plurality of hinges 425 or by any other suitable means. When lid portion 410 is closed over recessed portion 415 and portable computing device 500, a sealing element 460 is compressed between lid portion 410 and housing 440, thereby forming a seal between housing 440 and lid portion 410. As described above, the seal formed between lid portion 410 and housing 440 can consist of one or more of a moisture seal, a debris seal, and a vapor seal, for example. Thus, when portable computing device 500 is encased within housing 440, sealing element 460 can prevent damage to portable computing device 500 when portable computing device 500 is used, for example, outside during a hurricane or dust storm. Housing 440 and lid portion 410 may also include one or more of insulating elements 470. Insulating elements 470, which are formed of an insulating material such as foam or the like, are preferably positioned in and around recessed portion 415 of housing 440 and lid portion 410. For example, insulating elements 470 may be positioned on the inner side of lid portion 410 facing recessed portion 415 and on the bottom and sides of recessed portion 415. Thus, when portable computing device 500 is encased within housing 440, insulating elements 470 effectively surround portable computing device 500. In the alternative, insulating elements 470 may be formed integrally within housing 440. For example, housing 440 and lid portion 410 may be constructed of a material that is naturally insulating. Insulating elements 470 insulate portable computing device 500 from external conditions that may be harmful to portable computing device 500. For example, insulating elements 470 may provide thermal insulation to protect portable computing device 500 from extreme external temperatures, for example, extreme heat or cold. Thus, if portable computing device 500 is encased within housing 440 and is used in extremely cold conditions, for example, in the arctic, insulating elements 470 insulate portable computing device 500 and prevent portable computing device 500 from freezing. Insulating elements 470 may also function as shock-absorbing elements. In this case, insulating elements 470 protect portable computing device 500 from external vibrations that may be harmful to portable computing device 500. For example, insulating elements 470 can absorb external vibrations that impact housing 440. Thus, if housing 440 is subjected to potentially harmful levels of vibration, for example, being dropped or being used in a vehicle in motion, insulating elements 470 protect portable computing device 500 from those vibrations. Therefore, if portable computing device 500 is encased within housing 440 and is used in a manner that would normally expose portable computing device 500 to potentially harmful shocks and vibrations, for example, in a moving vehicle, insulating elements 470 absorb those vibrations and prevent the vibrations from damaging portable computing device 500. When portable computing device 500 is encased within housing 440, portable computing device is in communication with one or more peripherals, for example, a rugged display 405 and a rugged user input device 435. Other peripherals may include a mouse, a printer, a network, a phone jack, etc. As is shown in FIGS. 4A-4D, these rugged peripherals may be mounted directly on, or be formed integrally with, housing 440 or lid portion 410. For example, rugged display 405 may be mounted directly on, or be formed integrally with, housing 440 and rugged user input device 435 may be mounted directly on, of formed integrally with, lid portion 410. The rugged peripherals, for example, rugged display 405 and rugged user input device 435, are designed for use in harsh and potentially harmful environments. As with housing 440, each of the peripherals preferably includes an outer shell similar to outer shell 420 of housing 440. In addition, each of the rugged peripherals should be resistant to external conditions of concern. For example, if system 400 is used in a wet environment, for example, during a hurricane, and sealing element 460 includes a moisture seal, it is preferable for each of the rugged peripherals to also be resistant to moisture. Therefore, when portable computing device 500 is encased within housing 440 as described above, portable computing device 500 may be operated using rugged peripherals mounted on or formed integrally with housing 440, such as rugged user input device 435 and rugged display 405. Accordingly, portable computing device 500 may be used via the rugged peripherals in unfavorable and potentially damaging conditions without exposing portable computing device 500 to those conditions. As is described above and shown in the enclosed figures, the invention relates to a system for protecting a portable computing device wherein the system comprises a device housing adapted to protectively encase a portable computing device, a protectively hardened user input device mounted on, or in communication with, the device housing, and a protectively hardened display mounted on, or in communication with, the device housing. When the portable computing device is encased within the device housing, a user of the portable computing device can operate the portable computing device via the protectively hardened user input device and the protectively hardened display, thereby allowing and enabling use of the portable computing device while preventing exposure of the portable computing device to potentially harmful operational conditions. Moreover, the housing may also encase a portable computing device in the closed position while still enabling a user of the portable computing device to operate the portable computing device via the protectively hardened user input device and the protectively hardened display. In addition, the device housing may further comprise one or more of a sealing element, an insulating element, and a shock-absorbing element. Furthermore, the device housing may be formed of many different types of materials including, but not limited to, plastic materials or metal materials. The invention may be applied to and used in conjunction with all types of portable computing devices. Some examples of acceptable portable computing devices include laptop computers, personal digital assistants (PDA's), and handheld computers. Thus, the invention allows a user to pay only once for the high cost of an environmentally rugged system that uses a potentially inexpensive portable computing device and then simply replace the portable computing device with another potentially inexpensive unit as necessary upon the original unit's failure or obsolescence. Also, the invention permits government and other certifications for harsh environments to be accomplished only once, for the case itself, without the need to recertify for each computing device. This can yield tremendous time and cost savings. For the first time, the invention permits the most up to date devices to be used in harsh environments, such as the battlefield. The invention further allows a user to simply use his own portable computing device preloaded with software and data, or an encrypted computer system, with the environmentally rugged system of the invention. It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made, in carrying out the above processes, in a described instrument, and in the construction set forth, without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention, which, as a matter of language, might be said to fall there between. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates generally to a system for protecting a portable computing device. More specifically, the present invention relates to a system for protecting a portable computing device which allows use of the portable computing device without exposing any of the integrated components of the portable computing device to potentially harmful operational conditions. Since the advent of personal computers, manufacturers and industrial users have continually developed faster, smaller and more versatile machines, including portable computers that are dedicated to perform a specific function such as word processing, data collection or item identification. Alternatively, portable computing devices may be all purpose computing machines capable of running a variety of types of software programs. These portable computing devices, such as personal computers, may interact with a variety of portable and stationary peripheral input/output devices such as printers, light pens, image scanners, video scanners, etc. Moreover, these computers may have an electric power cord for receiving power from a standard electric outlet, as well as a battery pack for powering the unit when an electric outlet is unavailable or is inconvenient. The portability and versatility of portable computers, in combination with the ever decreasing size and weight of these machines, has attracted a significant number of users, with the number of users expected to dramatically increase in the near term. The design and versatility of portable computers have progressed significantly, and in addition to laptop computers, personal digital assistants (PDAs), tablet computers, and other handheld computers have become popular. Laptop computers generally include an upper housing for a display, a lower housing for a keyboard, and a pivot for pivotally attaching the upper housing to the lower housing. Such construction is often referred to as “clam shell” construction. Generally, the upper housing and display are rotated away from the keyboard when the user wishes to utilize the portable computer, and are similarly rotated toward the keyboard when the palm top or portable computer is not in use. The cost of these versatile portable computers continues to decrease as they are becoming increasingly common in all areas of business and personal life, and the manufacturers enjoy savings due to the economies of scale associated with mass production. Alternatively, many types of portable computers are designed to fill a specific need, for example, the need for a portable computer that can withstand a rugged environment. While devices of this type offer added convenience to the end user, and are manufactured of heavier materials, these devices are generally more application specific and thus do not enjoy the economies of scale associated with mass production. Thus, these “ruggedized” or “hardened” portable computers cost significantly more than a typical portable computer. In cases wherein the computer may be dropped, exposed to high amounts of moisture, dirt, extreme temperatures, etc., a typical portable computer may be irreparably damaged. Therefore, users are forced to continue to purchase ruggedized computers at an increased cost to prevent having to frequently repair or replace their typical portable computers due to their operational conditions. Also, ruggedizing, also known as “hardening”, to extend the range of operating conditions, such as temperature, vibration, and shock, that can be sustained by the device is very expensive, especially considering the testing and certifications that must be performed for government and other compliance applications. Moreover, computer technology is one of the most rapidly developing technological fields in industry today. A top of the line portable computer is likely to be outdated as soon as within a year from its release in the marketplace, and may also be eventually unusable due to the system requirements of newer software applications. Similarly, interactive and multimedia applications, which are becoming increasingly popular, require significantly higher system performance than traditional word processing applications. Thus, users are forced to frequently replace their existing computers to maintain a high level of technological capability. With the increased cost of ruggedized portable computers as compared to typical portable computers, frequent upgrading and replacement of portable computer can be quite costly and is not desirable. In some instances, such as government specification applications, replacement might not be possible due to the length of time required for the applicable certification testing. However, the ever increasing overhaul required for typical operating systems and application software require that hardware be upgraded frequently. In an attempt to overcome this problem, those skilled in the art have attempted to enable the use of typical portable computers in rugged environments by designing protective cases of housings which can protect the portable computer during transport, etc. Various U.S. patents relate to this technology such as U.S. Pat. No. 6,297,236 issued to Seok, U.S. Pat. No. 5,632,373 issued to Kumar et al., and U.S. Pat. No. 5,214,574 issued to Chang. However, these protective cases still do not enable a user to operate a typical portable computer in harsh and rugged environments. In particular, the protective cases only protect the portable computer from environmental conditions while the computer is not being operatied, for example, during transport. When the portable computer is being operated, the computer and its peripherals are exposed to the environment. Thus, if the portable computer is being operated in the rain, for example, the protective cover will protect the portable computer from the rain until the computer is opened and operatied, at which time the computer will be unprotected. While protective cases, membranes, and the like are utilized for other types of electronic devices while still allowing use of the device, for example, a waterproof case for a non-waterproof camera, none of the existing protective cases offer protection for a device as complex or demanding as a portable computer or allow for the use of peripherals, such as a keyboard and a display, as is preferred for successful operation of a portable computer. | <SOH> SUMMARY OF INVENTION <EOH>A preferred embodiment of the invention relates to a system for protecting a portable computing device, the system comprising a device housing adapted to protectively encase the portable computing device to prevent exposure of the portable computing device to potentially harmful operational conditions, the portable computing device including at least one of a user input device and a display, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing, wherein the device housing allows a user of the portable computing device to operate the portable computing device via the protectively hardened user input device and the protectively hardened display. In addition, a preferred embodiment of the invention relates to a system for protecting a communications device having at least one communications port, the system comprising a device housing adapted to protectively encase the communications device, the device housing having at least one interface corresponding to the at least one communications port of the communications device, a protectively hardened user input device in communication with the device housing, and a protectively hardened display in communication with the device housing. The protectively hardened input device may be one of an interface, a keyboard, a mouse, a touch pad, or a joystick, for example. Accordingly, the at least one interface of the device housing may enable at least one of configuration, control, and management of the communications device or portable computing device via the protectively hardened user input device. Moreover, the device housing may further comprise a sealing element, such as a moisture seal, a debris seal, a vapor seal, a electromagnetic seal, or an insulating element, such as thermal insulation, an electromagnetic interference (EMI) shield, or a radio frequency interference (RFI) shield. The device housing may also include a shock-absorbing element to attenuate any vibrations. In additional, the device housing may be formed of a plastic material, a metal material, or any other suitable material. Moreover, if the portable computing device or communications device includes an upper housing for housing a display, a lower housing for housing a user input device, and a hinge element for pivotally connecting the upper housing to the lower housing and enabling the portable computing device or communications device to rotate around the hinge element into an open position and a closed position, the device housing further comprising a recessed portion for protectively encasing the portable computing device or communications device when the portable computing device or communications device is in the closed position. Accordingly, the device housing may allow a user of the portable computing device or communications device to operate the portable computing device or communications device via the protectively hardened user input device and the protectively hardened display when the portable computing device or communications device is in the closed position and is protectively encased within the recessed portion of the device housing. The portable computing device or communications device may be communicatively coupled to the device housing, using electrical, optical, electromagnetic, or other communication mechanisms. Furthermore, the protectively hardened user input device and the protectively hardened display may be mounted on the device housing. Accordingly, the device housing may allow a user of the portable computing device or communications device to operate the portable computing device or communications device via the protectively hardened user input device and the protectively hardened display without exposing the portable computing device or communications device to potentially harmful operational conditions of use. The invention may be applied to and used in conjunction with all types of portable computing devices or communications devices. Some examples of acceptable portable computing devices include laptops, personal digital assistants, handheld computers, routers, switches, hubs, telephones, cellular and other mobile telephones, or optical communications equipment. Some examples of such communications devices include routers, hubs, or switches. Examples of optical communications equipment include optical multiplexers and de-multiplexers. These and other features, objects and advantages of the present invention will be in part apparent to those skilled in art and in part pointed out hereinafter. | 20050121 | 20080304 | 20060727 | 68532.0 | G06F116 | 1 | LEA EDMONDS, LISA S | SYSTEM FOR PROTECTING A PORTABLE COMPUTING DEVICE | SMALL | 0 | ACCEPTED | G06F | 2,005 |
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11,038,424 | ACCEPTED | Broadcast method in wireless network and communication apparatus using the same | A broadcast method in a wireless network and a communication apparatus using the same. The broadcast method determines whether the broadcast packet is first received upon receiving a broadcast packet. If a determination reveals that the packet is first received, the broadcast packet is stored and rebroadcast to neighbor nodes. Subsequently, a node, among the neighbor nodes, from which the broadcast packet is received, is marked as ‘relayed’. The broadcast packet is rebroadcast when all of the neighbor nodes from which the broadcast packet is received are not marked as ‘relayed’. When all of the neighbor nodes from which the broadcast packet is received are marked as ‘relayed’, the broadcast packet is destroyed. Accordingly, an efficient link-based broadcast method is provided. | 1. A broadcast method in a wireless network comprising the steps of: receiving a broadcast packet; determining whether the broadcast packet is first received; storing the broadcast packet and rebroadcasting the broadcast packet to neighbor nodes when the broadcast packet is first received; and destroying the broadcast packet when the broadcast packet is not first received. 2. The broadcast method of claim 1, wherein the first received packet is a received packet that is not the same as a previously received packet. 3. The broadcast method of claim 1, further comprising the steps of marking a node, among the neighbor nodes, from which the broadcast packet is received as ‘relayed’; checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time; and rebroadcasting the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are not marked as ‘relayed’. 4. The broadcast method of claim 3, further comprising the step of destroying the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are marked as ‘relayed’. 5. The broadcast method of claim 3, wherein a rebroadcast timer counts the predetermined time, thereby setting a rebroadcast time. 6. The broadcast method of claim 3, wherein the predetermined time is set based on a link quality indicator (LQ) value of the received broadcast packet. 7. The broadcast method of claim 3, wherein the rebroadcast step is repeated a number of times corresponding to a predetermined value, at intervals of the predetermined time until all of the neighbor nodes relay the broadcast packet. 8. The broadcast method of claim 1, wherein the wireless network is a ZigBee network compliant to the IEEE 802.15.4 standard. 9. The broadcast method of claim 8, wherein the marking step sets a neighbor list corresponding to information relative to the neighbor nodes, and marks the nodes listed in the neighbor list. 10. The broadcast method of claim 9, wherein the neighbor list is set using a bitmap based on an index of the listed neighbor nodes. 11. The broadcast method of claim 9, wherein the listed neighbor nodes are located within one hop from a broadcast source. 12. The broadcast method of claim 9, wherein the listed neighbor nodes are grouped based on a ZigBee address, and the grouped neighbor nodes are checked to determine whether the grouped neighbor nodes are marked as ‘relayed’. 13. A broadcast method in a wireless network, comprising the steps of receiving a broadcast packet; determining whether a designated field in a header of the broadcast packet is set; rebroadcasting the broadcast packet according to a reliable broadcast method when the designated field is set; and rebroadcasting the broadcast packet according to a unreliable broadcast method when the designated field is not set. 14. The broadcast method of claim 13, wherein the wireless network is a ZigBee network compliant to IEEE 802.15.4. 15. The broadcast method of claim 14, wherein the reliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and rebroadcasts the broadcast packet after a predetermined time if there is a node, among neighbor nodes, which does not relay the broadcast packet, and wherein the reliable broadcast method destroys the broadcast packet if the packet is not first received. 16. The broadcast method of claim 14, wherein the unreliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and destroys the broadcast packet if the broadcast packet is not first received. 17. The broadcast method of claim 14, wherein the designated field is a ‘Lost Parent’ field in a packet control field included in the header of the broadcast packet. 18. A communication apparatus using a broadcast method in a wireless network, comprising: a means for receiving a broadcast packet; a means for determining whether the broadcast packet is first received; a means for storing and rebroadcasting the broadcast packet to neighbor nodes if the broadcast packet is first received; and a means for destroying the broadcast packet if the broadcast packet is not first received. 19. The communication apparatus of claim 18, further comprising: a means for marking a node, among the neighbor nodes from which the broadcast packet is received, as ‘relayed’; a means for checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time; and a means for rebroadcasting the broadcast packet if all of the neighbor nodes are not marked as ‘relayed’. 20. The communication apparatus of claim 19, further comprising a means for destroying the broadcast packet if all of the neighbor nodes are marked as ‘relayed’. | CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the priority of Korean Patent Application No. 2004-84309 filed on Oct. 21, 2004 in the Korean Intellectual Property Office and U.S. Provisional Patent Application No. 60/544,226 filed on Feb. 13, 2004 in the United States Patent and Trademark Office, the disclosures of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a broadcast method in a wireless network and a communication apparatus using the broadcast method. More particularly, the present invention relates to a broadcast method in a wireless network and a communication apparatus using the broadcast method, which are capable of efficiently broadcasting data by a link-based broadcast in a ZigBee network compliant to the IEEE 802.15.4 standard. 2. Description of The Related Art In contrast to a Local Area Network (LAN) or a Wide Area Network (WAN), a Personal Area Network (PAN) is a network owned by an individual. Devices owned by the individual are interconnected to construct a network in order to provide convenience for the owner. The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 802.15 Working Group developed the WPAN for short distance wireless networks to standardize and implement the PAN. The IEEE 802.15 standard has four Task Groups. More particularly, IEEE 802.15.1 standardizes the well-known Bluetooth technology, whereas IEEE 802.15.3 and IEEE 802.15.3a standardizes the high rate WPAN. Additionally, IEEE 802.15.4, alias ZigBee, standardizes low rate WPAN which corresponds to data rates less than 250 kbps. One of the goals of ZigBee is to standardize the protocol stacks above a media access control (MAC) layer for wireless sensor networks. To this end, the current ZigBee specification supports reliable data broadcast at a network layer. A broadcast method specified in the ZigBee specification consists of three major parts, which include a network-wide broadcast, a local broadcast repair, and a limited radius broadcast. FIGS. 1 through 4 illustrate conventional broadcast methods according to the ZigBee specification. Referring now to FIGS. 1 through 4, the conventional broadcast methods of the ZigBee specification and drawbacks associated with the conventional broadcast methods are described below. FIG. 1 illustrates the network-wide broadcast mechanism in the ZigBee network which is specified in the ZigBee specification. According to the ZigBee specification, the network-wide broadcast mechanism is a tree-based broadcast in which broadcast packets are only forwarded via a tree structure. For example, if the source of a broadcast packet is a node A in a network as shown in FIG. 1, the broadcast packet must be transmitted through its parent node in order to reach neighbor nodes because the broadcast packet is delivered only following the tree structure. Thus, transmission of the broadcast packet from node A to node B or node C, as shown in FIG. 1, requires six transmissions and relays following the tree structure. However, by utilizing physical links instead of the tree structure, the broadcast packet can be delivered to node B or node C (of FIG. 1) via three or four nodes along links indicated as dotted lines in FIG. 1. Therefore, the transmission of the broadcast packets following the tree structure according to the ZigBee specification delays the delivery of the broadcast packets unnecessarily. FIG. 2 illustrates the local broadcast repair mechanism in the ZigBee network. As explained above, the broadcast method of the ZigBee specification utilizes a parent and child relationship based on the three structure. If a node loses contact with its parent node, a broadcast packet is not delivered farther. The local broadcast repair mechanism is used to repair the lost link in such a situation. The ZigBee specification specifies that a child node, which loses contact with its parent node, performs a local broadcast repair using a ‘Lost Parent’ bit in a packet control field included in a packet header. However, there is no solution with respect to delivery of a broadcast packet from a parent node when the parent node loses contact with the child node. For example, if a link between node C and node B is broken, as shown in FIG. 2, node F can receive a packet from a node, such as node G, via another branch of node C. However, since the packet received from node G is not delivered from its parent or child node, the packet is discarded. As a result, the sub-tree under node B is not covered. FIG. 3 illustrates the limited radius broadcast mechanism used in a ZigBee network. According to the limited radius broadcast mechanism, a range to which a broadcast packet reaches can be set using a radius counter (RC) value. Referring to FIG. 3, a node 0 performs the limited radius broadcast with RC=2. The RC value decreases by 1 every time the broadcast packet is retransmitted from each node. The broadcast packet is not retransmitted farther when the RC value becomes zero. The limited radius broadcast, which allows the tree structure, may present undesired results. For example, as shown in FIG. 4, if nodes F and G are one-hop neighbor nodes and node F attempts to perform the limited radius broadcast with RC=3, the broadcast packet will not be delivered to the node G. In order to reach node G, the limited radius broadcast has to be performed with RC=4. That is, the RC value needs to be unnecessarily large to cover neighbor nodes, and therefore, unnecessary traffic increases. SUMMARY OF THE INVENTION To address the problems described above with respect to the conventional broadcast methods which correspond to the ZigBee specification, an aspect of the present invention provides a link-based broadcast method in a wireless network. To achieve the above aspect of the present invention, the broadcast method in a wireless network comprises the steps of receiving a broadcast packet, determining whether the broadcast packet is first received, storing the broadcast packet and rebroadcasting the broadcast packet to neighbor nodes when the broadcast packet is first received, and destroying the broadcast packet when the broadcast packet is not first received. The wireless network is a ZigBee network compliant to the IEEE 802.15.4 standard. The broadcast method further comprises marking a node, among the neighbor nodes, from which the broadcast packet is received as ‘relayed’, checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time, and rebroadcasting the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are not marked as ‘relayed’. The broadcast method further comprises the step of destroying the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are marked as ‘relayed’. A rebroadcast timer counts the predetermined time, thereby setting a rebroadcast time. The predetermined time may be set based on a link quality indicator (LQI) value of the received broadcast packet. The rebroadcast step is repeated a number of times corresponding to a predetermined value at intervals of the predetermined time until all of the neighbor nodes relay the broadcast packet. Thus, unrestricted rebroadcast is prevented. The marking step sets a neighbor list corresponding to information relative to the neighbor nodes, and marks nodes listed in the neighbor list. The neighbor list is set using a bitmap based on an index of the listed neighbor nodes. The listed neighbor nodes are located within one hop from a broadcast source. The listed neighbor nodes are grouped based on a ZigBee address and the grouped neighbor nodes are checked to determine whether the grouped neighbor nodes are marked as ‘relayed’. Consistent with an aspect of the present invention, a broadcast method in a wireless network comprises receiving a broadcast packet, determining whether a designated field in a header of the broadcast packet is set, rebroadcasting the broadcast packet according to a reliable broadcast method when the designated field is not set, and rebroadcasting the broadcast packet according to an unreliable broadcast method when the designated field is set. The wireless network mentioned above is a ZigBee network compliant to the IEEE 802.15.4 standard. The reliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and rebroadcasts the broadcast packet after a predetermined time if there is a node, among the neighbor nodes, which does not relay the broadcast packet. If the packet is not first received, the reliable broadcast method destroys the broadcast packet. The unreliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and destroys the broadcast packet if the broadcast packet is not first received. The designated field is a ‘Lost Parent’ field in a packet control field included in the header of the broadcast packet. Consistent with an aspect of the present invention, a communication apparatus using a broadcast method in a wireless network, comprises a means for receiving a broadcast packet, a means for determining whether the broadcast packet is first received, a means for storing and rebroadcasting the broadcast packet to neighbor nodes if the broadcast packet is first received, and a means for destroying the broadcast packet if the broadcast packet is not first received. The communication method further comprises a means for marking a node, among the neighbor nodes, from which the broadcast packet is received, as ‘relayed’, a means for checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time, and a means for rebroadcasting the broadcast packet if all of the neighbor nodes are not marked as ‘relayed’. The communication apparatus further comprises a means for destroying the broadcast packet if all of the neighbor nodes are marked as ‘relayed’. BRIEF DESCRIPTION OF THE FIGURES These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawing figures of which: FIGS. 1 through 4 are diagrams of conventional broadcast methods according to a ZigBee specification; FIGS. 5A and 5B are flowcharts of a broadcast method according to a first embodiment of the present invention; FIG. 6 is a diagram of an exemplary embodiment of a neighbor list; FIG. 7 is a diagram of an exemplary embodiment of a packet control field; and FIG. 8 is a diagram illustrating that a neighbor list is built by grouping neighbor nodes. DETAILED DESCRIPTION OF THE EMBODIMENTS Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below in order to explain the present invention by referring to the drawings. A broadcast method in a wireless network according to exemplary embodiments of the present invention utilizes a link-based broadcast rather than a parent node and child node relationship which is based on a tree-based broadcast. Accordingly, the parent node and the child node relationship which is based on the tree structure are not the only nodes that can participate in the delivery of broadcast packets. In other words, all nodes can participate in the delivery of broadcast packets according to the broadcast method of the present invention. The broadcast method in the wireless network according to the present invention is primarily applied to a ZigBee network compliant to the IEEE 802.15.4 standard However, the broadcast method according the present invention is not limited to the ZigBee network. For instance, any network meeting the criteria corresponding to embodiments of the present invention may be employed. FIGS. 5A and 5B are flowcharts of the broadcast method in the wireless network according to a first embodiment of the present invention. Referring initially to FIG. 5A, a node linked to the wireless network receives a broadcast packet (S100), and the node determines whether the received packet is first received (S105). The first received packet denotes that the received packet is not the same as a previously received packet. A determination is made as to whether the packet is first received by checking the presence of packet information corresponding to the received packet in a broadcast transaction record (BTR) of a broadcast transaction table (BTT). If the determination performed at step S105 reveals that the packet is first received, a BTR corresponding to the received packet is created and stored in the BTT (S110). The BTR created corresponding to the received packet contains a source address and a broadcast sequence number (BCSN) of the packet. After creating the BTR, the received broadcast packet is stored in a buffer and a rebroadcast timer is set (S115). The rebroadcast timer is used to determine a rebroadcast time. Subsequently, the received packet is rebroadcast at step S120. In step S125, each of the neighbor nodes in the neighbor list from which the broadcast packet is received are checked and marked as ‘relayed’, as shown in FIG. 6. According to the present invention, the neighbor list organizes information relating to neighbor nodes within one hop from a broadcast source. In order to mark a relayed field of the neighbor list a bitmap based on an index of each node is utilized. The length of the bitmap equals the number of neighbor nodes in the neighbor list. If it is determined at step S105 that the packet has been received, each of the neighbor nodes in the neighbor list from which the broadcast packet is received are checked and marked as ‘relayed’ when the source address of the received packet corresponds to the neighbor nodes in the neighbor list (S130). After the neighbor nodes in the neighbor list are marked as ‘relayed’ in step S130, the received packet is destroyed in step S140. As a result, the received broadcast packet is processed. Referring to FIG. 5B, when the set rebroadcast timer expires after a predetermined time (S150), a determination is made as to whether all of the neighbor nodes in the neighbor list are marked as ‘relayed’ (S155). If the determination reveals that each of the neighbor nodes are not marked as ‘relayed’, the received packet is rebroadcast in step S170 and the rebroadcast timer is re-set in step S175. A Maximum Retransmission Limit parameter to count the number of times rebroadcast has occurred is increased (S180). If the Maximum Retransmission Limit parameter is below a predetermined value (S195), steps S150 through S180 are repeated. Accordingly, the number of the times rebroadcast may occur is limited to the predetermined value. As a result, unrestricted rebroadcast is not allowed. If all of the neighbor nodes in the neighbor list are marked as ‘relayed’ at step S155, the packet stored in the buffer is cleared (S160) and the BTR is cleared (S165). In other words, the packet is destroyed when all of the neighbor nodes from which the packet is received are marked as ‘relayed’. As a result, it is guaranteed that all the neighbor nodes receive the broadcast packet according to the link-based broadcast. A broadcast method according to a second embodiment of the present invention selectively utilizes a reliable broadcast method and an unreliable and best-effort broadcast. According to the second embodiment of the present invention, an ‘Unreliable Broadcast’ field is newly defined, and the broadcast method is selected depending on whether the ‘Unreliable Broadcast’ field is set. For example, if the ‘Unreliable Broadcast’ field is not set, the broadcast method using the neighbor list according to the first embodiment of the present invention is used. In other words, when the ‘Unreliable Broadcast’ field is not set, the reliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and rebroadcasts the broadcast packet after a predetermined time if there is a node, among the neighbor nodes listed in the neighbor list, which does not relay the broadcast packet. If the packet is not first received, the reliable broadcast method destroys the broadcast packet. On the contrary, if the ‘Unreliable Broadcast’ field is set, the broadcast packet is not forwarded according to the reliable method as in the first embodiment of the present invention. Instead, according to the unreliable broadcast method, the broadcast packet is forwarded if the packet is first received and the broadcast packet is destroyed if the broadcast packet is not first received. Additionally, when the ‘Unreliable Broadcast’ field is set, the creation of the BTR is maintained. However, marking of the corresponding neighbor node in the neighbor list as ‘relayed’ is not utilized. Referring to FIG. 7, the ‘Unreliable Broadcast’ field can use a ‘Lost Parent’ field in a packet control field which is added into a header at a network layer. A ‘Broadcast’ bit, a ‘Lost Parent’ bit, and a ‘Broadcast Radius Present’ bit in the packet control field respectively relate to the network-wide broadcast, the local broadcast repair, and the limited radius broadcast of the ZigBee specification. As described above, broadcast method according to the exemplary embodiments of the present invention allows all nodes to participate in the forwarding of the broadcast packet. Thus, there is no need to utilize the local broadcast repair to find the link to the parent node. Accordingly, the ‘Lost Parent’ field can be used as the ‘Unreliable Broadcast’ field. A broadcast method according to a third embodiment of the present invention selectively utilizes tree-based and link-based limited radius broadcasts. To this end, a ‘Tree-based Broadcast’ sub-field is added in the header of a packet control field. By default, the ‘Tree-based Broadcast’ sub-field is not set, and the link-based limited radius broadcast according to the first embodiment of the present invention is utilized. However, if the ‘Tree-based Broadcast’ sub-field is set, the tree-based limited radius broadcast is utilized according to the conventional broadcast methods of the ZigBee specification. When building a neighbor list which includes information regarding the nodes within one hop from a broadcast source, it is possible to group the nodes based on the parent and child relationship by using a ZigBee address. FIG. 8 illustrates that a neighbor list is built by grouping neighbor nodes. Referring to FIG. 8, the first to third neighbor lists 210, 310 and 410 are built for the first to third areas 200, 300 and 400, respectively. Nodes 6 and 7 are in the parent and child relationship in the first and second neighbor lists 210 and 310. Nodes 8, 9, and 10 are in the parent and child relationship in the third neighbor list 410. After grouping the neighbor nodes in the parent and child relationship, and once the broadcast packet is received from one of the nodes in a specific group, all nodes in the corresponding group are checked and marked as ‘relayed’ according to the normal reception of the broadcast packet in the neighbor list. Nodes in a group, which share a superframe, enable reliable transmission within the group. In addition, waiting time at a source node is reduced. When determining a rebroadcast time, the received broadcast packet may be rebroadcast to nodes in an order corresponding to the distance away from the source node by setting a backoff value in proportion to a link quality indicator (LQI) value of the received broadcast packet. In this situation, if the rebroadcast packet generated at the node farthest from the source node is received, the nodes close to the source node receive the packet in the usual manner. Since the node farthest from the source node performs the rebroadcast, high-speed broadcast can be performed over the entire network. In light of the foregoing, each of the nodes linked to a wireless network can participate in the forwarding of the broadcast packet according to the link-based broadcast. Since the broadcast packet is delivered along the links, the broadcast packet is performed faster than the tree-based broadcast. The tree structure is not utilized according to the embodiments of the present invention, and therefore, the local broadcast repair mechanism to repair the tree structure is not needed. Since the link-based limited radius broadcast is utilized, it is possible to efficiently set the transmission range of the broadcast packet, and the RC value represents the actual limited hop. If needed, it is possible to selectively utilize the reliable broadcast and the unreliable and best-effort broadcast. The rebroadcast time can be efficiently set by grouping the neighbor list by use of the ZigBee address, or, according to the LQI value. While the exemplary embodiments of the present invention have been described, additional variations and modifications of the exemplary embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims shall be construed to include the aforementioned exemplary embodiments and all such variations and modifications that fall within the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention generally relates to a broadcast method in a wireless network and a communication apparatus using the broadcast method. More particularly, the present invention relates to a broadcast method in a wireless network and a communication apparatus using the broadcast method, which are capable of efficiently broadcasting data by a link-based broadcast in a ZigBee network compliant to the IEEE 802.15.4 standard. 2. Description of The Related Art In contrast to a Local Area Network (LAN) or a Wide Area Network (WAN), a Personal Area Network (PAN) is a network owned by an individual. Devices owned by the individual are interconnected to construct a network in order to provide convenience for the owner. The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 802.15 Working Group developed the WPAN for short distance wireless networks to standardize and implement the PAN. The IEEE 802.15 standard has four Task Groups. More particularly, IEEE 802.15.1 standardizes the well-known Bluetooth technology, whereas IEEE 802.15.3 and IEEE 802.15.3a standardizes the high rate WPAN. Additionally, IEEE 802.15.4, alias ZigBee, standardizes low rate WPAN which corresponds to data rates less than 250 kbps. One of the goals of ZigBee is to standardize the protocol stacks above a media access control (MAC) layer for wireless sensor networks. To this end, the current ZigBee specification supports reliable data broadcast at a network layer. A broadcast method specified in the ZigBee specification consists of three major parts, which include a network-wide broadcast, a local broadcast repair, and a limited radius broadcast. FIGS. 1 through 4 illustrate conventional broadcast methods according to the ZigBee specification. Referring now to FIGS. 1 through 4 , the conventional broadcast methods of the ZigBee specification and drawbacks associated with the conventional broadcast methods are described below. FIG. 1 illustrates the network-wide broadcast mechanism in the ZigBee network which is specified in the ZigBee specification. According to the ZigBee specification, the network-wide broadcast mechanism is a tree-based broadcast in which broadcast packets are only forwarded via a tree structure. For example, if the source of a broadcast packet is a node A in a network as shown in FIG. 1 , the broadcast packet must be transmitted through its parent node in order to reach neighbor nodes because the broadcast packet is delivered only following the tree structure. Thus, transmission of the broadcast packet from node A to node B or node C, as shown in FIG. 1 , requires six transmissions and relays following the tree structure. However, by utilizing physical links instead of the tree structure, the broadcast packet can be delivered to node B or node C (of FIG. 1 ) via three or four nodes along links indicated as dotted lines in FIG. 1 . Therefore, the transmission of the broadcast packets following the tree structure according to the ZigBee specification delays the delivery of the broadcast packets unnecessarily. FIG. 2 illustrates the local broadcast repair mechanism in the ZigBee network. As explained above, the broadcast method of the ZigBee specification utilizes a parent and child relationship based on the three structure. If a node loses contact with its parent node, a broadcast packet is not delivered farther. The local broadcast repair mechanism is used to repair the lost link in such a situation. The ZigBee specification specifies that a child node, which loses contact with its parent node, performs a local broadcast repair using a ‘Lost Parent’ bit in a packet control field included in a packet header. However, there is no solution with respect to delivery of a broadcast packet from a parent node when the parent node loses contact with the child node. For example, if a link between node C and node B is broken, as shown in FIG. 2 , node F can receive a packet from a node, such as node G, via another branch of node C. However, since the packet received from node G is not delivered from its parent or child node, the packet is discarded. As a result, the sub-tree under node B is not covered. FIG. 3 illustrates the limited radius broadcast mechanism used in a ZigBee network. According to the limited radius broadcast mechanism, a range to which a broadcast packet reaches can be set using a radius counter (RC) value. Referring to FIG. 3 , a node 0 performs the limited radius broadcast with RC=2. The RC value decreases by 1 every time the broadcast packet is retransmitted from each node. The broadcast packet is not retransmitted farther when the RC value becomes zero. The limited radius broadcast, which allows the tree structure, may present undesired results. For example, as shown in FIG. 4 , if nodes F and G are one-hop neighbor nodes and node F attempts to perform the limited radius broadcast with RC=3, the broadcast packet will not be delivered to the node G. In order to reach node G, the limited radius broadcast has to be performed with RC=4. That is, the RC value needs to be unnecessarily large to cover neighbor nodes, and therefore, unnecessary traffic increases. | <SOH> SUMMARY OF THE INVENTION <EOH>To address the problems described above with respect to the conventional broadcast methods which correspond to the ZigBee specification, an aspect of the present invention provides a link-based broadcast method in a wireless network. To achieve the above aspect of the present invention, the broadcast method in a wireless network comprises the steps of receiving a broadcast packet, determining whether the broadcast packet is first received, storing the broadcast packet and rebroadcasting the broadcast packet to neighbor nodes when the broadcast packet is first received, and destroying the broadcast packet when the broadcast packet is not first received. The wireless network is a ZigBee network compliant to the IEEE 802.15.4 standard. The broadcast method further comprises marking a node, among the neighbor nodes, from which the broadcast packet is received as ‘relayed’, checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time, and rebroadcasting the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are not marked as ‘relayed’. The broadcast method further comprises the step of destroying the broadcast packet when all of the neighbor nodes from which the broadcast packet is received are marked as ‘relayed’. A rebroadcast timer counts the predetermined time, thereby setting a rebroadcast time. The predetermined time may be set based on a link quality indicator (LQI) value of the received broadcast packet. The rebroadcast step is repeated a number of times corresponding to a predetermined value at intervals of the predetermined time until all of the neighbor nodes relay the broadcast packet. Thus, unrestricted rebroadcast is prevented. The marking step sets a neighbor list corresponding to information relative to the neighbor nodes, and marks nodes listed in the neighbor list. The neighbor list is set using a bitmap based on an index of the listed neighbor nodes. The listed neighbor nodes are located within one hop from a broadcast source. The listed neighbor nodes are grouped based on a ZigBee address and the grouped neighbor nodes are checked to determine whether the grouped neighbor nodes are marked as ‘relayed’. Consistent with an aspect of the present invention, a broadcast method in a wireless network comprises receiving a broadcast packet, determining whether a designated field in a header of the broadcast packet is set, rebroadcasting the broadcast packet according to a reliable broadcast method when the designated field is not set, and rebroadcasting the broadcast packet according to an unreliable broadcast method when the designated field is set. The wireless network mentioned above is a ZigBee network compliant to the IEEE 802.15.4 standard. The reliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and rebroadcasts the broadcast packet after a predetermined time if there is a node, among the neighbor nodes, which does not relay the broadcast packet. If the packet is not first received, the reliable broadcast method destroys the broadcast packet. The unreliable broadcast method rebroadcasts the broadcast packet if the broadcast packet is first received, and destroys the broadcast packet if the broadcast packet is not first received. The designated field is a ‘Lost Parent’ field in a packet control field included in the header of the broadcast packet. Consistent with an aspect of the present invention, a communication apparatus using a broadcast method in a wireless network, comprises a means for receiving a broadcast packet, a means for determining whether the broadcast packet is first received, a means for storing and rebroadcasting the broadcast packet to neighbor nodes if the broadcast packet is first received, and a means for destroying the broadcast packet if the broadcast packet is not first received. The communication method further comprises a means for marking a node, among the neighbor nodes, from which the broadcast packet is received, as ‘relayed’, a means for checking whether all of the neighbor nodes are marked as ‘relayed’ after a predetermined time, and a means for rebroadcasting the broadcast packet if all of the neighbor nodes are not marked as ‘relayed’. The communication apparatus further comprises a means for destroying the broadcast packet if all of the neighbor nodes are marked as ‘relayed’. | 20050121 | 20080923 | 20050818 | 67978.0 | 0 | HSU, ALPUS | BROADCAST METHOD IN WIRELESS NETWORK AND COMMUNICATION APPARATUS USING THE SAME | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,457 | ACCEPTED | Methods and apparatuses for filtering water | The invention relates to a method and apparatus for filtering or purifying water. | 1. A recycling apparatus for recycling wash solution from a power washer: a holding tank constructed and arranged for holding filtered wash solution and having at least one opening to the environment to allow air to freely transfer between the holding tank the environment; a first filter assembly in gravity feed relation with the holding tank, said first filter assembly having a first filter sheet; a second filter assembly in gravity feed relation with holding tank, said third filter assembly having a second filter sheet having a filtration size of 10 microns or less, wherein said first and second filter assemblies are constructed and arranged such that during operation a first filtered wash solution from the first filter assembly filters through the second filter assembly to form a recycled wash solution and drops into the holding tank a second distance of from about 1 to about 30 inches before contacting recycled wash solution in the holding tank; and a power washer in communication with the recycled wash solution in the holding tank; and screen structure constructed and arranged for collecting wash solution sprayed from the power washer during operation and transferring the wash solution to the first filter assembly. 2. A recycling apparatus according to claim 1, wherein the first and second filter assemblies are constructed and arranged such that during operation the wash solution filters through the first filter assembly to form the first filtered wash solution and drops into the second filter assembly a first distance of from about 1 to about 30 inches before contacting first filtered wash solution in the second filter assembly. 3. A recycling apparatus according to claim 1, further comprising a pump constructed and arranged to provide pressurized recycled wash solution from the holding tank of a pressure sufficient to operate the power washer. 4. A recycling apparatus according to claim 1, further comprising an oil separator tank, wherein the oil separator tank comprises an oil skimmer and an intake at a lower portion of the oil separator tank for supplying oil reduced wash solution to the first filter assembly during operation. 5. A recycling apparatus according to claim 4, further comprising at least one agitator in the oil separator tank to prevent sediment buildup. 6. A recycling apparatus according to claim 1, further comprising an agitator in said holding tank connected to a pump such that during operation recycled wash solution flows from the holding tank to at least one of the filter assemblies. 7. A recycling apparatus according to claim 1, further comprising at least one other filter assembly in gravity feed relation with any of the first and second filter assemblies. 8. A recycling apparatus according to claim 1, wherein each filter assembly is slidable in relation to each other for ease of replacement of the filter sheets. 9. A recycling apparatus according to claim 1, wherein each filter assembly is adjustable in height such the distance the filtered wash solution drops is adjustable. 10. A recycling apparatus according to claim 1, wherein each filter assembly comprises a mesh screen and means for holding the filter sheet in place. 11. A recycling apparatus according to claim 1, wherein the filter sheet is cut to size from a roll of filter material. 12. A recycling apparatus according to claim 1, wherein a distance the filtered wash solution drops from the second filter assembly to the holding tank is from about 2 to about 24 inches. 13. A recycling apparatus according to claim 1, wherein a distance the filtered wash solution drops from the second filter assembly to the holding tank is from about 3 to about 12 inches. 14. A recycling apparatus according to claim 1, wherein a distance the filtered wash solution drops from the second filter assembly to the holding tank is from about 4 to about 8 inches. 15. A recycling apparatus according to claim 1, wherein the first filter sheet has a filtration size of about 10 microns or less. 16. A recycling apparatus according to claim 1, wherein the first filter sheet has a filtration size of about 10 microns or less and the second filter sheet has a filtration size of about 1 microns or less. 17. A recycling apparatus according to claim 1, wherein the filter assemblies are sized to provide at least a 5 gallon per minute flow rate under ambient pressure and gravity. 18. A recycling apparatus according to claim 1, wherein the power washer is a car wash, a steam washer, or a laundry machine. 19. A recycling apparatus according to claim 1, wherein the power washer is constructed and arranged to accept the recycled wash solution containing both wash chemicals and water in a water inlet of the power washer. 20. A method of recycling wash solution from a power washer comprising; filtering wash solution through a first filter assembly having a first filter sheet under ambient pressure to form a first filtered wash solution and allowing the first filtered wash solution to flow into a second filter assembly; filtering the first filtered wash solution through the second filter assembly having a second filter sheet of 10 micron or less filtration size under ambient pressure to form a recycled wash solution and allowing the recycled wash solution to drop a second distance into a recycled wash solution tank before contacting a surface of the recycled wash solution being contained in the recycled wash solution tank, the second distance being sufficient to aerate the recycled wash solution in the recycled wash solution tank; supplying the recycled wash solution to a power washer; washing an object with the recycled wash solution; collecting wash solution from the washing step; and supplying at least a portion of the collected wash solution to the first filter assembly for recycling. 21. A method according to claim 20, further comprising the step of continuously monitoring the level of wash solution in the recycled wash solution tank and automatically adding water as needed. 22. A method according to claim 20, further comprising transferring recycled wash solution from the recycled wash solution tank to at least one of the first and second filter assemblies to remove precipitates formed in the recycled wash solution tank. 23. A method according to claim 20, further comprising the step of removing oil from the wash solution prior to filtering through the first filter assembly. 24. A method according to claim 20, further comprising using a 10 micron or less filtration size in the first and second filter sheets. 25. A method according to claim 20, further comprising using filtration size of about 0.2 microns or less in the second filter assembly to remove heavy metals from solution. 26. A method according to claim 20, further comprising cutting the first and second filter sheets having a width of at least 1 foot and a length of at least 2 feet from one or more rolls of sheet material. 27. A method according to claim 20, further comprising drying a used filter, combining the dried used filter with powder coating materials, and firing the used filter and powder coating materials in an oven to bind the heavy metals. 28. A method according to claim 27, wherein the powder coating materials are waste powder coating materials collected from the floor following powder coating an object. 29. A method according to claim 20, further comprising filtering the first filtered wash solution through at least one other filter assembly before supplying the filtered wash solution to the second filter assembly. 30. A method according to claim 20, wherein the power washer is a car washer, a steam washer, or a laundry machine. 31. A method according to claim 20, further comprising screening the collected wash solution to remove particles prior to supplying the collected wash solution to the first filter assembly. 32. A method according to claim 20, wherein any pumps used to move the solution are air pressure driven. 33. A method according to claim 20, wherein the filtered wash solution comprises wash chemicals and the filtered wash solution is supplied to the water inlet of the power washer. 34. A method according to claim 20, wherein the filtered wash solution comprises water run-off from vehicles. 35. A method according to claim 20, wherein the first and second filter assemblies are constructed and arranged such that during operation the wash solution filters through the first filter assembly to form the first filtered wash solution and drops into the second filter assembly a first distance before contacting first filtered wash solution in the second filter assembly to provide aeration. 36. A flat roll filter material comprising: an inner flat roll filter material impregnated with an active material that removes an undesired material from water filtered therethrough, the inner flat roll material being encased by two outer flat roll filter materials that are sealed along a length of the flat roll. 37. A flat roll filter material according to claim 36, wherein said inner filter material is a larger size than said outer flat roll filter materials. 38. A flat roll filter material according to claim 36, wherein said inner filter material has a size of from about 1 to about 10 microns and said outer filter materials have a size of about 1 micron or less. 39. A flat roll filter material according to claim 36, wherein said inner filter material has a size of from about 1 to about 5 microns and said outer filter materials have a size of about 0.5 to about 0.01 micron. 40. A flat roll material according to claim 36, wherein the active material is selected from the group consisting of activated charcoal, lignite, laterite and positive charged polymers. 41. A flat roll material according to claim 40, wherein the active material is present in an amount from about 1 to about 90% by weight. 42. A flat roll material according to claim 40, wherein the active material is present in an amount from about 10 to about 50% by weight. | This application is a Continuation-in-Part of U.S. appl'n Ser. No. 10/939,335, filed Sep. 14, 2004, which is a Continuation of U.S. appl'n Ser. No. 10/636,808, filed Aug. 8, 2003, which claims priority to U.S. appl'n Ser. No. 60/411,382, filed Sep. 18, 2002; 60/408,281, filed Sep. 6, 2002; 60/406,059, filed Aug. 27, 2002; 60/404,403, filed Aug. 20, 2002; and 60/402,526, filed Aug. 12, 2002, the complete disclosures of which are incorporated herein by reference. This application also claims priority to U.S. patent appl'n Ser. Nos. 60/632,076, filed Dec. 1, 2004; 60/618,605, filed Oct. 15, 2004; 60/598,443, filed Aug. 4, 2004; 60/542,872, filed Feb. 10, 2004; and 60/538,240, filed Jan. 23, 2004, the complete disclosures of which are incorporated herein by reference. 1. FIELD OF THE INVENTION The invention relates to methods and apparatuses for filtering and/or purifying water, for example, from wash solutions used in spray washing, steam cleaning or car washes, as well as water run off from other applications, and well, river, lake and ocean water. 2. BACKGROUND OF THE INVENTION There have been many attempts to filter water. One such conventional recycling apparatus is sold commercially under the Cyclonator™ name. A description can be found on the internet at www.cyclonator.com. This system uses numerous hoses to and from a specially designed washing platform, an additional separate filtering tank to remove larger debris and oils, a special holding tank, and two vacuum canister type filters that require expensive filters. This recycling apparatus provides no visual monitoring ability except for vacuum gauges, has no pH monitoring nor automatic adjustment capability, and the location of the unit has to be in close proximity to the wash platform and the power washer. Furthermore, the filtering apparatus is difficult to maintain, requires a large area of space and numerous extra equipment at additional cost. Moreover, the vacuum or pressure used to force the wash solution through a filter can undesirably force dirt through filters. There are many other systems that use pressure or vacuum, including those from Cyclonator standard filtration weir, www.cyclonator.com; Powder-X Pretreatment Station, Powder-X Coating Systems, Inc., www.powder-x-.com; Rapid Pretreatment Station, www.rapidengineering.com; PKG Equipment, Inc., www.pkgeguipment.com; Water Treatment Tech Equipment, MFG.; Pressure Island; Arkal Filtration; ADF-Liquid Filtration; Kemco Systems; and Tiger Enterprises, 39126 Alston Ave., Zephyrhills, Fl 33542. Two open water filtration systems, CFS3 and CMAFU-2 are commercially sold by HydroEngineering, disclosed at www.hydroblaster.com. However, in these systems the filtered water is not continuously filtered through the filter media and there is only one filter media. While there are other filtering systems disclosed on the website which refer to circulation of water for multiple passes through polishing media (see description of Model ACF3) this appears to be a closed system since hydrobiodigesters must be utilized. Furthermore, conventional water purification systems for producing potable water from non-potable water are complicated, difficult to use and require extensive maintenance. An example of such a system utilizes reverse osmosis. There is a need for an improved water filtering apparatus that does not require a vacuum or pressure pumps, provides easy visual inspection of the filters during operation, is easy to maintain and operate, and can be scaled to any size operation. There is also need for a simplified water purification system for producing potable water from non-potable water. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A illustrates a side view of the water filtering apparatus; FIG. 1B illustrates a view of a filter assembly; FIG. 2A illustrates a view of a horse water filtering apparatus; FIG. 2B illustrates a view of a horse water filtering apparatus; FIG. 3A illustrates a view of a potable water filtration system; FIG. 3B illustrates a view of a magnetic filter mount; FIG. 3C illustrates a view of an activated material impregnated flat roll Filter material; FIG. 4A illustrates a view of a water filtering apparatus and spray washer; FIG. 4B illustrates a partial cut-away side view of a water filtering apparatus; FIGS. 4C through 4E illustrate views of a filter assembly; FIG. 4F illustrates a clamp for mounting a filter material in a filter assembly; and FIG. 4G illustrates a basin for collecting filtered solution. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention will now be described with reference to preferred embodiments as shown in the Figures. The claimed invention is not limited to these preferred embodiments. As shown in FIG. 1A, the water filtering apparatus 1 comprises a main tank 2. The main tank 2 can be sized as desired for the particular application. An example of a suitable size tank 2 is 4 feet high by 4 feet wide by 8 feet long. The main tank 2 is constructed of 14 gauge mild steel, but can be constructed of any desired material that is suitable to hold the filtered solution. Examples of suitable materials include, but are not limited to, metals, alloys, rubbers, plastics, glass, coated wood, or fiberglass. Preferably, if metal parts are utilized in the recycling apparatus 1, the metal parts are powder coated to prevent rust. The main tank 2 contains a holding tank 3 defined by baffle 4. The baffle 4 can be formed from the same material as the holding tank, or any material suitable to hold the filtered solution. If desired, separate tanks can be used instead of splitting one large tank into smaller tanks with the use of baffles. The main tank 2 contains three cascading filter assemblies 20, 30 and 40. The filter assemblies 20, 30 and 40 are sized to removably fit within the main tank 2, as shown in FIG. 1. More or less filter assemblies can be utilized as desired for the particular application. Each filter assembly has an associated filter material 24, 34 and 44. The filter material can be selected for the particular application. Preferably, the filter material is a small size in the direction of the water flow to enhance the life time of the smaller filter size material. For example, filter paper 24 can be 15 micron size, filter paper 34 can 1 micron size, and filter paper 44 can be 0.5 micron size. Filter assemblies 20 and 30 are constructed such that filter assembly 20 can be rotated up about axis 22 to expose filter assembly 30, and filter assembly 30 can rotated up about axis 32 to expose the filter assembly 40. The filter assemblies 20 and 30 rest on respective holders 26 and 36. In this manner, the filter material can easily be changed for each filter assembly 20, 30 and 40 without completely removing the filter assembly (although they can be removed easily if needed) from the main tank 2. Filter assembly 40 rests on holders 46. Respective handles 38 and 40 facilitate removal of the filter assemblies 30 and 40 from the main tank 2, when desired. The filter assemblies 20, 30 and 40 are constructed such that water to be filtered is introduced to filter assembly 20. After the water passes through the filter material 24 it falls into filter assembly 30. After the water passes through the filter material 34 it falls into filter assembly 40. After the water passes through filter material 44 it falls into holding tank 3. The filter assemblies and apparatus can also utilize any and all apparatus disclosed in my copending U.S. Ser. No. 10/636,808, filed Aug. 7, 2003, the complete disclosure of which is incorporated herein by reference. As shown in FIG. 1B, the filter assembly 20 comprises ½ to ¾ inch expanded steel mesh 23 having a V-shape, but can be any shape to allow maximum ability in any given circumstance. In this example, the ends of the filter assembly 20 are sealed using plates 25 designed to conform to whatever style filter holder is needed. The filter material 24 is held in place using the magnetic filter holder 600 as described below. In this example a 5 foot wide filter paper is uses, so the expanded steel mesh 23 is sized such that it is about 5 feet in length, shown from A to B in FIG. 1B. The filter assembly 40 is constructed and arranged such that during operation, the filtered solution drops about 1 inch to 30 inches, more preferably from about 2 inches to about 24 inches, more preferably from about 3 inches to about 12 inches, and most preferably about 6 to about 8 inches, before contacting the surface of the filtered water in the holding tank 3 to provide suitable aeration to prevent or inhibit mold formation and to allow volatiles to escape. Preferably, the filter assemblies are offset so that water dripping from the bottom of a higher filter assembly contacts a side surface of a lower filter assembly. Even more preferably, the filter assemblies 20, 30 and 40 are v-shaped and constructed such that water to be filtered is delivered to at least one side of filter assembly 20, filtered water dripping from the bottom of the v in filter assembly 20 contacts a side of filter assembly 30 and filtered water dripping from the bottom of the v in filter assembly 30 contacts a side of filter assembly 40. In this manner, the water path though the filter material is significantly longer than merely the thickness of the filter material. The filter assemblies can be formed in many different ways to conform to the needs of the situation. If desired, the filtered water in holding tank 3 can flow therefrom into another filter assembly 50. The filter assembly 50 is constructed to be removable from the main tank 2. To facilitate ease of removal, the filter assembly 50 contains an arm 51. The filter assembly 50 as an associated filter material 54. After the water flows through the filter material 54, it leaves the main tank 2 through exit 60. However, filtered water can be taken directly from the holding tank 3 for use. A power washer can be connected to the filtering apparatus 1 in a manner similar as disclosed herein below or my earlier U.S. appl'n Ser. No. 10/939,335, filed Sep. 14, 2004, such that used wash solution can be collected and filtered, and filtered wash solution can be supplied from the holding tank 3 to the power washer for reuse. The water level in the holding tank 3 can be monitored using a water lever monitor 5, which can be any conventional water level monitor, such as commonly used in toilets or the well-known water levelers used in the commercially available Swamp Cooler™. In an alternative embodiment, a closed door system (CDS) can be utilized in which the main tank 2 is used as the holding tank for the wash water that will be going to the power washer. In this embodiment, a typical tank is 4 feet high by 4 feet wide by 10 feet long. It will then have a holding tank capacity of at least 266 gallons. 4 feet of the length can go under the incoming filters and 6 feet can become a prewash holding tank by using a baffle. The baffle can be sized to provide any depth of water, for example 18 inches from bottom of tank up. In this embodiment, no water is discharged to the sewer. The wash water can contain wash chemicals as desired. The size and structure of the filter assembly can be varied as desired. Preferably, the size of the filter should be such that at least a 5 gallon per minute flow rate is provided under ambient pressure and gravity. The preferred filter material is a rolled filter sheet material that is easily obtained from commercial manufacturers or from a filter supply company. The spool is usually about three feet to about five feet wide and about one hundred or more feet long. Preferably, the filter sheet material is at least 20 inches wide, more preferably at least 30 inches wide, and most preferably at least 60 inches wide. The filter sheet material is easily cut to any desired length or width to fit the filter assembly. Examples of preferred commercially available filter sheet materials include, but are not limited to, the BR-60 and BR-80 series from Mountain States Filter, Colorado. The filter sheet material easily takes any desired shape in the filtering apparatus. While inexpensive flat sheets of filter cloth, synthetic or natural, are preferred filters, any suitable filter material can be used as desired for the particular application. The filters usually last about 1 week in duration before changing is required, but should be monitored daily. Usually, the filter material is formed from plastics. However, in certain applications, the filter material preferably comprises cellulose or wood products for environmental friendly disposal, such as incineration or shredding. The filter can be selected by the end user to provide the desired level of filtering based on the particular application. It has been found that filters having a size of less than 10 microns are preferred. A preferred arrangement is the use of a filter having a size of about 3 to 8 microns in the filter assembly 30, and about 1 micron or less in each of the filter assemblies 32 and 34. However, the size of the filter can be varied as desired for the particular application. Prior to introducing the water into filter 20, oil can be mechanically or manually removed from the water using well know techniques, such as an oil skimmer. The main tank 2 also preferably contains recycling apparatus, such as pump 8, which continually recycles filtered water from holding tank 3 to at least one of the filter assemblies 20, 30 or 40. It is believed that this continuous recycling is responsible for unexpectedly removing unwanted contaminates, such as those shown in the Examples, which the filter material is not know for being capable of removing. It is also believed that the filter performance increases over time due to sediment building in the filter material. Furthermore, it is also believed that salts present in solution may crystallize out of solution on the filters during the continuous recycling. It is also believed that the aeration reduces unwanted buildup of undesired organic volatiles and even facilitates removal of unwanted organic compounds and salts from the water. Using the present invention, it has surprisingly been found that numerous unwanted salts, inorganic compounds and organic compounds are surprisingly removed using filter materials that are known not be capable of removing these compounds. A small electrical charge or magnets can be applied to the system to enhance the capabilities of the filter media. For example, an electric jolt to the solution to be treated can change the properties of the contaminants and make the filter media more effective. Furthermore, a UV light source can be used to provided UV light to the filtered water in the holding tank or to the filtered water anywhere as desired in the filtering apparatus. The state of Colorado is currently in an extreme drought condition and the land that many businesses are located on does not accommodate leaching a large amount of water discharge through the sewage leach field. Public sewage may also not be within reach. With my new water filtering apparatus, the wastewater and the drought are no longer an issue. This embodiment is useful for purifying water to meet EPA guidelines for disposal. It has been extensively tested at Colorado Department of Transportation sites to purify water running off from trucks, which contains salts, metals, inorganic compounds and organic compounds that the EPA prohibits from disposing in sewers. The filtering apparatus removed all of the materials the EPA required and the filtered water complied with EPA guidelines for disposal in sewers. The filtering apparatus can also be used for recycling wash solutions, such as spray washing, car washes, steam washers and laundry machines. Further, the filtering apparatus is applicable whenever purifying to comply with environmental guidelines, or recycling of water and/or chemicals present in the water is desired. Horse Water Horses are sensitive to elevated levels of iron in water. It has been found that the method and apparatus described herein can be used to reduce iron levels, as well as undesirable heavy metals, in water to make it safer for horses. Any of the cascading filter systems described herein can be used. If desired, a self generating horse water filtering apparatus 400 as shown in FIGS. 2A-2B can also be used. The horse water filtering apparatus includes main tank 401. A holding tank 404 is defined by the main tank 401 and baffles 401 and 402. A rotating filter assembly 410 includes filter material 412. The filter material 412 is sized to remove iron from the water. Preferably, the filter material 412 is about 0.2 micron or less. The filter material 412 rotates about shafts 414 and 416. Water to be filtered is introduced by water input 418. The water flows through the filter material 412 and drops onto collecting sheet 420. The filtered water drops off of the collecting sheet 420 and into holding tank 404. Sediments removed by the filter material 412 drop off of and into a sediment trap 428. Optionally, to facilitate sediment removal, air can be blown through the filter material 412 from air supply 430. The sediment trap 428 can be a light-weight trap that is removable from the main tank 401 for easy cleaning. The filter material 412 is rotated during operation. Water leaving the holding tank 404 can be used to drive a paddle wheel 440 or other device for powering the rotation of the filter material 412, such as solar, wind, electrical, gas or other power means. If a paddle wheel 440 is used, the paddle wheel 440 can be connected to the shaft 416 using pulleys 441 and 442 to drive the filter material 412. The paddle wheel 440 can also be used to drive a bellows to power the air supply 430 to clean the filter material 412. The filtered water can exit the main tank 401 through exit 450 and flow to a water trough to be consumed by horses. Preferably, a biodegradable filter material 412 is used, such as wood fiber. Water Clean Up Post Forest Fire. When forest fires burn a large area of vegetation, it has been found that the vegetation releases a significant quantity of undesirable contaminates, such as lead, mercury, and other heavy metals. Since the filtering systems described herein are capable of removing such contaminates from water on a large scale economically, the runoff water from streams and creeks leaving the forest fire area can easily be purified using the present invention. Potable Water The potable water system will be described with reference to FIGS. 3A and 3B. Incoming water to be treated flows through a conduit 512 and into a pre-sediment tank 510 where anti-algae fighting additives can be introduced to the contained water 518. The pre-sediment tank 510 can comprise baffles 514 and 516 to facilitate removal of sediments from the water 518. If desired, other designs for removing sediments from the incoming water can be utilized. The water is then pumped into a primary filtration tank 520 using pump 521 and filtered using the degree of filters as deemed necessary. A cascading filter system having four filters is shown in FIG. 3A. The first filter 522 is a 1 micron filter, the second filter 524 is a 0.5 micron filter and the third filter 526 is a 0.2 micron filter. Any desired filter size, such as from about 0.01 micron to about 10 micron filters, can be used as desired for the particular application. The water should flow through a 0.2 micron or less filter. The preceding filters having a larger size are used to prefilter the water to extend the life of the 0.2 micron or less filter. The water then can flow through a fourth filter 528 if desired. The water is then drained or pumped using pump 540 into a secondary filtration tank 550 containing a series of filters 552, 554 and 556. The water can be continuously recycled between the primary filtration tank 520 and secondary filtration tank 550 using pump 560. Additives can be added as desired. The water is then exposed to UV light by pumping it using pump 570 to a glass walled cylinder 572 around an ultra-violet light assembly 574. After being exposed to UV light, the water is pumped using pump 580 to a final holding tank 590 and through a final stage of filters 592, 594 and 596. These filters preferably comprise a flat roll filter material 700 infiltrated with activated charcoal, as shown in FIG. 3C. A charcoal impregnated flat filter 701 encased on two sides by outer filter materials 702 and 704. Filter materials 702 and 704 are sealed along the length of the filter material 700 at 706 and 708 using any desired sealing method, such as sonic welding, heat sealing or gluing. Preferably, the outer filter materials 702 and 704 are a smaller size than the inner activated charcoal impregnated filter material 701. For example, the filter materials 702 and 704 can be in the range of about 5 micron and less in size, preferably about 1 micron or less, more preferably about 0.5 to about 0.01 micron in size, and the filter material 701 can be about 1 to about 10 microns, preferably about 1 to about 5 microns in size. In another embodiment, the outer filter 704 is a smaller size than the outer filter 702 and the filter assembly is used such that the flow of water is through the larger size outer filter 702 before the smaller size outer filter 704. For example, in this embodiment the outer filter 702 has a size of 5 microns or less and the outer filter 704 has a size of 0.5 to 0.1 micron in size. Final additives can be introduced in the final holding tank 590. Clean potable water can be removed through outlet 598. Pumps may be deleted as desired by using a cascading assembly. Some, or all, of the filters can be of an automated roller system with sensors that can automatically advance the filter paper as needed. One or more of the tanks can be deleted depending on the particular application. The filters and filter assemblies can be as described in my co-pending U.S. patent application Ser. No. 10/636,808, filed Aug. 7, 2003, the complete disclosure of which is incorporated herein by reference. The first and second filter assemblies can be hinged for easy change out of the filter material without having to remove the whole filter tray, as described above. The filter material can be held in place using the structure shown in my co-pending application or by a magnetic filer holder comprising bar magnets as shown in FIG. 3B. The magnetic filter holder 600 is a channel style with two to three small magnets 602 set inside a channel 604. The magnets 602 are not held in by glue, but by powder coating the channel 604 with an epoxy powder, inserting the magnets 602 inside the channel 604 and then baking the unit to melt cure the epoxy powder and bind the magnets 602 to the channel 604. This is a much more cost effective way than the very expensive glues that are currently being used. It is my belief that we will also be able to remove salt from sea water by adding magnesium chloride or another substance that will bond to, or react, to sea water and then filtering the sea water through our recycling system described herein. It is believed that the magnesium chloride bonds to the sea salt making the molecular structure large enough to be filtered out by using our 0.2 micron or the 0.05 micron filter material. It may be possible to shred the material and reuse the combined amalgam to salt roads, or the amalgam may be removed and the filter material reused. Without being bound by any theory, it is also believed that when chlorides pass through the plastic filter material the chlorides become charged and are removed by the filter. Filter Material The filters preferably comprise a flat roll filter material 700 infiltrated or impregnated with an active material, as shown in FIG. 3C. An active material impregnated flat filter 701 encased on two sides by outer filter materials 702 and 704. Filter materials 702 and 704 are sealed along the length of the filter material 700 at 706 and 708 using any desired sealing method, such as sonic welding, heat sealing or gluing. Preferably, the outer filter materials 702 and 704 are a smaller size than the inner activated charcoal impregnated filter material 701. For example, the filter materials 702 and 704 can be in the range of about 5 micron and less in size, preferably about 1 micron or less, more preferably about 0.5 to about 0.01 micron in size, and the filter material 701 can be about 1 to about 10 microns, preferably about 1 to about 5 microns in size. In another embodiment, the outer filter 704 is a smaller size than the outer filter 702 and the filter assembly is used such that the flow of water is through the larger size outer filter 702 before the smaller size outer filter 704. For example, in this embodiment the outer filter 702 has a size of 5 microns or less and the outer filter 704 has a size of 0.5 to 0.1 micron in size. Examples of suitable active materials include a material that binds or otherwise removes an undesired material from the water filtered therethrough. Examples of suitable active materials include activated charcoal, lignite, positive charged polymers, laterite, silver, and activated aluminum. Other examples other examples of active materials include antibacterial and antifungal agents. The activate material can be present in an effective amount for removing the undesired material from water filtered therethrough. Examples of suitable amounts is from about 1% to about 90%, preferably from about 10% to about 50%, and most preferably about 30%, by weight. Power Washer Recycling As shown in FIGS. 4A-4G, the recycling apparatus 200 comprises a main tank 202 that is about four and a half feet wide, about four feet deep, and about four feet high. The exemplary main tank 202 is sized to operate with one standard spray washer operating at a maximum of about 5 gallons per minute. The main tank 202 can be sized for any desired flow rate and number of spray washers. The main tank 202 is constructed of 14 gauge mild steel, but can be constructed of any desired material that is suitable to hold the filtered solution. Examples of suitable materials include, but are not limited to, metals, alloys, rubbers, plastics, glass, coated wood, or fiberglass. Preferably, if metal parts are utilized in the recycling apparatus 1, the metal parts are powder coated to prevent rust. The main tank 202 has about a 1.25 inch lip around the top formed by rolling the sheet metal back on itself to provide improved strength and safety. Wash solutions are well-known and any conventional wash solution or even water run-off from vehicles can be used in the present recycling apparatus. While this embodiment is described with reference to the term “wash solution,” this embodiment may be used to filter any type of water to form potable water and/or to clean up water for discharging to the environment, such as salt water, mine water runoff, wash water, and residential and industrial waste water. The wash solution may contain one or more phosphates as desied. The wash solution may be acidic or basic as desired. The wash solution is preferably free-of chemicals that cannot be recycled, such as butyl cellusolve (a glycol ether), which can vaporize or break down at 175° F. and cause undesirable vapors during spray washing. Preferably, the wash solution is free-of heavy metals such as molybdate, that are environmentally unfriendly. A suitable commercially available phosphate that can be combined with water to form the wash solution is sold under the name DuBoise Diversy/Lever, secure steam ultra. In some embodiments, the wash solution will be recovered filtered water from spraying trucks with fresh water and/or run off from trucks, as shown in the Examples below. Connected to the main tank 202 is a filtering tank 208. The filtering tank 208 is about seven feet long, about 4 feet deep and about 3 feet high. The filtering tank is split into two separate tanks for holding the filtered wash solution, second tank 210 and primary tank 212 by baffle 211. The baffle 211 is about 6 inches high. The baffle can be formed from the same material as the holding tank, or any material suitable to hold the filtered solution. If desired, separate tanks can be used instead of splitting one large tank into smaller tanks with the use of baffles. The filtering tank 208 contains associated pairs of slide rails 213, 214, 215 and 216 on two opposite inside surfaces for holding filter assemblies 220, 221, 222, 223, and 224. The filter assemblies each have associated mounts 225 formed from angle iron pieces welded to the filter assembly for movably holding the filter assembly on a pair of slide rails. Each filter assembly can be slid on a pair of slide rails for ease of replacing the filters, removing the filter assemblies, and/or for aligning the filter assemblies. FIG. 4B shows the filter assemblies in a preferred location, such filter assembly 220 drops filtered solution into one side of the filter assembly 221, and each successive filter assembly drops the filtered wash solution into a side of the next lower filter assembly. The filter assemblies and slide rails are constructed and arranged such that during operation, the filtered wash solution drops about 1 inch to 30 inches, more preferably from about 2 inches to about 24 inches, more preferably from about 3 inches to about 12 inches, and most preferably about 6 to about 8 inches, before contacting the surface of the wash solution in the next filter below or tank to provide aeration. The bottom of the filter assembly 221 is angled toward the center as shown in FIGS. 4C and 4D and formed of expanded mesh or perforations to allow the wash solution to pass through. In this manner, the flat filter material 228 lays down and substantially conforms to the shape of the filter assembly 221. Small creases may form in the filter material 227. The filter material is held in place on the edges from A to B using rods 228 and clamps 229. Any number of clamps 229 can be used to hold the rod 228 in place and apply pressure against the filter material 228 and filter assembly 221. Instead of rods, any shaped material can be used. If desired, the filter material 228 can be held in place using any of the means described herein, such as the magnetic filter holders. The other filter assemblies have structure similar to that described for filter assembly 221. If desired, any of the filter assemblies described herein or in my co-pending application U.S. Ser. No. 10/636,808, filed Aug. 8, 2003, the complete disclosure of which is incorporated herein by reference, can be utilized. The preferred filter assembly shown uses a flat rolled filter material 228, which can be purchased in spools three feet wide and 150 feet long and easily cut to the proper length. Examples of preferred commercially available filter materials include, but are not limited to, the BR-60 and BR-80 series from Mountain States Filter, Colorado. Preferably, the flat filter material comprises plastic. While inexpensive flat sheets of filter cloth are preferred filters, any suitable filter material can be used as desired for the particular application. Any of the filter materials described herein can be utilized. Used wash solution is collected and dirt separated therefrom in a pit 287 using the basin 289. The screened used wash solution is then pumped to an optional presediment tank 230 of the recycling apparatus using the pump 290 and line 291. The basin 289 is constructed to raise the pump 290 off of the bottom of the pit to reduce the amount of sediment transferred by the pump 290. The presediment tank 230 can be hung from the side of the as desired for the particular use. After sediments are removed from the wash solution in the presediment tank 230, the wash solution is dropped into the filter assemblies. The filtered wash solution leaving the filter assemblies drops into the primary tank 212. Filtered wash solution in primary tank 212 flows over the baffle 211 and into the second tank 210. Filtered water from the second tank 210 is transferred to the main tank 202 using the pump 240 and line 242. An optional filter 244 can be provided on the line 242 to further filter the filtered water before entering the main tank 202. Filtered wash solution from the main tank 202 is recycled to the filter assemblies using pump 250, line 252 and spreader 254. In this manner, wash solution is constantly recycled through the filter assemblies. Filtered wash solution from the main tank 202 can be supplied to the power washer 280 using outlet 260 and line 281. Preferably, the outlet 260 removes filtered wash solution at least one foot from the bottom of main tank 202, and more preferably at least 1.5 feet from the bottom of the main tank. It is believed that undesirable residual chlorides reside in greater quantity at the bottom of the main tank 202 if present in the filtered wash solution. The recycling apparatus 200 preferably contains a water level monitor 288 in the main tank 202 to alert the user of low wash solution conditions. If desired, the water level monitor 200 can be connected to a water supply to automatically add water to the recycled wash solution tank 200 through inlet 202 as needed. The water level monitor 200 can be any conventional water level monitor, such as commonly used in toilets or the well-known water levelers used in the commercially available Swamp Cooler™. The main tank 202 preferably contains one or more overflow outlets 26 that drain into the second tank 210 to prevent overfilling of the main tank 202. During operation, the recycling apparatus 200 is connected to a power washer 280 using hose 281. The power washers 280 heats the wash solution to any desired pressure and temperature, for example, about 180 to about 220° F. and about 1500 to about 3000 psi. The object to be washed is sprayed with the heated pressurized wash solution using the wand 286. The used wash solution is collected and the dirt separated therefrom in a pit 287 using the basin 289. The screened used wash solution is then pumped to the optional presediment tank 230 of the recycling apparatus using the pump 290 and line 291 to form a continuous loop through the recycling apparatus 200. Conventional spray washers 280 have two inputs, a fresh water input 282 and chemical input 284. When the present recycling apparatus is utilized in a manner to supply a recycled wash solution containing chemicals, it can be supplied to the spray washer 280 through the fresh water input 282. The chemical input 284 and any associated metering unit can be removed since they are no longer needed, which usually results in a desired increase of pressure at the spray wand 286. By using the present recycling apparatus, a less complicated spray washer 282 can be utilized that does not have a chemical input 284 and metering unit since the chemicals can be added to the recycling apparatus. The coil for heating fresh water in the spray washer 282 usually comprises black pipe and brass fittings, which can be corroded by the chemicals when present in the wash solution. Thus, preferably, if present, the black pipe and brass fittings are replaced with stainless steel or another material that does not corrode in the presence of the chemicals. Preferably, no high-voltage electricity is utilized in the water recycling or purifying apparatuses described herein to provide enhanced safety. In this regard, the pumps are all preferably pressurized air operated pumps. Commercial examples of suitable air operated pumps include those sold under the Ingersoll-Rand ARO line, such as the Model 6660. The air operated pumps are preferably mounted inside the tanks so that if there are any leaks in the pump they will be contained. However, if desired, the pumps can be mounted external to the tanks. The recycling apparatus and method described herein is environmentally friendly. Bacterial and fungus buildup in the recycling apparatus is substantially avoided without the use of environmentally unfriendly chemicals by a combination of continuous aeration and filtering. The phosphate, which is usually of the same type as used in laundry and dish washers as a cleaning and disinfecting agent, will help kill the bacteria. Furthermore, the high temperature achieved in the power washer will kill even more bacteria. Heat Recovery Many powder coating operations utilize an oven 300 for baking the powder coating thereon. Once the baking procedure is complete, the substantial amount of heat for heating the oven 300 is simply allowed to dissipate into the atmosphere. Applicant applies heat exchangers 302 and 304 to the oven to thereby transfer wasted heat from the oven 300 to the recycled wash solution 202 using lines 312, pump 310, outlet 308 and inlet 306. Optionally, the heated recycled wash solution leaving the heat exchangers 302 and 304 can be supplied directly to the line 281 and power washer 280 using line 314. The heat exchangers 302 and 304 can be turned off and on selectively using valve 303 so that the heat exchangers 302 and 304 are only on when the baking procedure is complete. Alternatively the heat exchanger 302 can be located above the oven 300 and turned on continuously, such that heat escaping from the oven 300 heats the heat exchanger 302 during and after the backing procedure. In this manner, the substantial cost of heating the power washing solution will be greatly reduced. Street Cleaners Street, sidewalk and floor cleaners containing a sprayer and vacuum system for sucking up sprayed cleaning solution have the problem of how to discard the waste. The filtration systems described herein can be used to treat the vacuumed wastewater so that it can be reused for cleaning surfaces. Portable Spray System The spray wash systems described herein can be made portable. The portable spray wash system includes a filtration system as described herein in communication with a power spray washer and generator to power the power spray washer and filtration system. The portable system also includes a vacuum system or portable drain system and pump to return the used wash solution to the filtration system. The whole system can be mounted on a portable transport. Dairies Dairies use large amounts of water in processing cheese. For example, vats, bottles and other equipment must be washed and rinsed and the cheese is formed in water. The waste water from this use can be filtered through any of our filtering systems described herein or our parent applications, and then used to clean sinks, tables, floors, etc. The filtering system can be modified and sized as desired for the particular application. If bacteria is a problem, silver nitrate or other antibacterial agents, or a UV light source, can be utilized. In the cheese industry, the loss of whey is great. Our filtering system can be used to separate the whey from the process water for reuse. Wineries Wineries use large amounts of water in processing wine. For example, vats, bottles and other equipment must be washed and rinsed prior to use. Furthermore, the manufactures of the bottles, such as Ball Jar, need to flush the bottles prior to usage. The waste water from these uses can be filtered through any of our filtering systems described herein or our parent applications, and then used to clean sinks, tables, floors, etc. The filtering system can be modified and sized as desired for the particular application. If bacteria is a problem, silver nitrate or other antibacterial agents, or a UV light source, can be utilized. PVC and Plastics Extrusion Plastics and pvc extrusion plants must cool their extruded product as it is forced out of the forming dies. The discharge water usually has a bacterial problem since the cooling water is typically in a closed system. By using one of our filter systems, with its aeration through the filters, in this case three to four separate filter levels, the water is oxygenated. Oxygenated water retards the growth of bacteria. The filter media is selected to remove contaminates from the water. Pumps may not be needed if the filtering system is higher than the holding vat for the water. A once pass through system is normally all that is required since the holding tank usually has its own associated pumping system to transfer treated water to the forming dies. A water filtration system was tested at an extrusion plant and the results are shown in the attached table entitled “Chemical Usage Post TASROP Installation.” As shown in that table, the plant had an annual chemical cost of $16,034 to treat the process water. During the past 8 months time, the process water quality was fair at best. On Sep. 7, 2004, a trial filtration system was installed. There was a visible marked improvement in the water quality. The expected annual cost savings is $8,500. Gypsum Natural gypsum and its man-made replacement can be added to water to form a slurry for flow purposes. After forming the desired shape, the water must then be removed. This discharged water normally picks up contaminates that prevent it from being recycled causing a loss of the water and any good gypsum from being reused. Depending on the size of the location, one or more filtering systems, having optimized pumps, filter media, filter numbers, flow meters, back flush devices and automated filter advancing capabilities, will allow the water and the separated product to be recycled. Uranium Recovery It is now known that certain bacteria have the ability to consume material containing uranium, such as waste uranium, and retain the uranium in their bodies. Thus, the bacteria can be spread over a waste site containing uranium and the bacteria will concentrate the uranium in their bodies. The bacteria containing uranium can be separated from their surroundings by filtration using the filter systems described herein. The bacteria and filter media containing them can then be combusted to provide concentrated uranium waste. In this manner, uranium can be recovered or separated easily and economically from a waste site or any desired site, including creeks and rivers. EXAMPLES In the Examples, the filter media was in a sheet form ranging from 1 foot wide×1 foot long to 6 feet wide×10 feet long. A sock style filter is currently being tested by the Colorado Department of Transportation (CDOT) that slides up over the lip on the pre-sediment tank and is tied to the spreader tube attached to the pre-sediment tank. This sock style filter is much easier to replace than the tray filter. The sock style filter can be formed by overlapping the filter sheet and sealing the ends. The filtration size of the media used ranged from about 0.01 micron (1 micron=0.000039 inches) to about 10 microns. Particular filtrations sizes used were 0.2 microns, 0.2 micron, 0.5 micron, 1 micron, 3 micron, 5 micron, and up in increments as needed. This varied in capability by as much as 25%. The micron capability is primarily determined by the weight of the cloth used and can be varied as needed. The manner in which the different filter media's were used depended on what the challenge was. Different media were used at different stages to accomplish a wide range of effects. Different filter media types were also used together to provide desired effects. We used from 1 to 5 filter assemblies in each filtration apparatus. The filter assemblies were layered as needed with the filter sheet media. Usually the filter sheet media was selected so that the filter assemblies above act to catch heavier or larger contaminants and the filter assemblies below catch anything that might leach out of the above filter assemblies. A water purification apparatus as shown in FIG. 1A was installed at the Frisco CDOT site. The water run-off from the CDOT trucks and equipment contains inorganic and organic contaminates that cannot be discarded using public waster water treatment. This waste water is currently trucked off site and stored in a storage facility. Once the storage facility reaches capacity, it costs the state of Colorado about $70,000 to have the waste water treated at a hazardous waste treatment site. The Frisco filtration system did not include the use of the 0.2 micron filter sheet material since it was not available. Water samples were collected and tested before (Pre-Test) and after filtration (TS-1, TS-2, and TS-3) by CDOT personnel. The test results are disclosed in Table 1 below. Water samples were also collected and tested before and after filtration by an independent test lab, Analytica. Analytica prepared three extensive test reports dated Dec. 29, 2003, Jan. 12, 2004 and Feb. 13, 2004, that are disclosed in U.S. appl'n ser. No. 60/598,443, filed Aug. 4, 2004, which is part of the present application. TABLE 1 TS-1 TS-2 TS-3 ANALYTE MCL Pre-Test Dec. 29, 2004 Jan. 12, 2004 Jan. 29, 2004 Volatile Organic Contaminents 1,1,1,2- 5 <1.2 ND ND ND Tetrachloroethane 1,1,1-Trichloroethne 200 <1.2 ND ND ND 1,1,2,2- 5 <1.1 ND ND ND Tetrachloroethane 1,1,2-Trichloroethane 5 <2.2 ND ND ND 1,1-Dichloroethane <1.4 ND ND ND 1,1-Dichloroethylene 7 <1.7 ND ND ND 1,1-Dichloropropene <0.93 ND ND ND 1,2,3- 70 <0.78 ND ND ND Trichlorobenzene 1,2,3- <2.5 ND ND ND Trichloropropane 1,2,4- 70 <0.59 ND ND ND Trichlorobenzene 1,2,4- 70 2.6 ND ND ND Trimethylbenzene 1,2-Dibromo-3- 0.2 <5.9 ND ND ND Chloropropane 1,2-Dibromomethane <0.86 ND ND ND 1,2-Dichlorobenzene 600 <1.1 ND ND ND 1,2-Dichloroethane 5 <1.8 ND ND ND 1,2-Dichloropropane 5 <1.8 ND ND ND 1,3,5- <1.2 ND ND ND Trimethylbenzene 1,3-Dichlorobenzene 620 <1.1 ND ND ND 1,3-Dichloropropane <0.66 ND ND ND 1,4- 75 <1.4 ND ND ND Dichlorobenzene(p−) 2,2-Dichloropropane <1.4 ND ND ND 2-Butanone <2.6 ND ND 2.7J 2-Chloroethyl Vinyl <1.2 ND ND ND Ether 2-Chlorotoluene <0.56 ND ND ND 2-Hexanone <0.87 ND ND ND 4-Chlorotoluene <1.2 ND ND ND 4-Isopropyltoluene <0.57 ND ND ND 4-Methyl-2-Pentanone <0.76 ND ND 86 Acetone 60 76B 6.6J 230 Acrylonitrile <1.6 ND ND ND Benzene 5 <0.88 ND ND .81J Bromobenzene <1.7 ND ND ND Bromochloromethane <1.7 ND ND ND Bromodichloromethane 0.56 <1.1 ND ND ND Bromoform 4 <1.6 ND ND ND Bromomethane <3.8 ND ND ND Carbon Disulfide <0.66 ND ND ND Carbon Tetrachloride 5 <0.85 ND ND ND Chlorobenzene 100 <0.55 ND ND ND Chloroethane <1.8 ND ND ND Chloroform 6 <1.3 ND ND ND Chloromethane <1.4 ND ND ND cis-1,2- 70 <1.2 ND ND ND Dichloroethylene cis-1,2- <0.38 ND ND ND Dichloropropene Dibromochloromethane 0.42 <1.6 ND ND ND Dibromomehane <1.1 ND ND ND Dichlorodifluoromethane <3.0 ND ND ND Ethyl Benzene 680 <0.93 ND ND ND Hexachlorobutadiene 1 <2.1 ND ND ND Iodomethane <2.1 ND ND ND Isopropylbenzene <0.40 ND ND ND m&p-Xylene 10,000 <0.76 ND ND ND Methylene Chloride 5 <5.8 ND ND ND Naphthalene <0.49 ND ND ND n-Butylbenzene <0.47 ND ND ND n-Propylbenzene <0.81 ND ND ND O-Xylene 10,000 <1.4 ND ND 1.7J sec-Butylbenzene <0.46 ND ND ND Styrene 100 <0.82 ND ND ND tert-Butyl Methyl Ether <0.61 ND ND ND tert-Butylbenzene <1.1 ND ND ND Tetrachlroethylene 5 <0.58 ND ND ND Toluene 1,000 <1.3 ND ND 1.8J trans-1,2- 100 <1.8 ND ND ND Dichloroethylene trans-1,2- 100 <0.99 ND ND ND Dichloropropene trans-1,4-Dichloro-2 100 <3.1 ND ND ND Buten Trichloroethylene 5 <1.3 ND ND ND Trichlorofluromethane <1.7 ND ND ND Trichlorotrifluoroethane <1.9 ND ND ND Vinyl Acetate <1.1 ND ND ND Vinyl Chloride 2 <1.6 ND ND ND Diesel Range Organics 230,000 8,100 Gasoline Range 970 <100 Organics Metals/Inorganics Aluminum 5,000 <6.6 3,360 69 449 Antimony 6 7.4 1.68 3.92 2.34 Arsenic 10 69 4.19 2.84 9.27 Barium 2,000 172 592 298 651 Boron 750b 4,700 310 310 1,100 Beryllium 4 <0.9 0.172 <.05 0.0553 Cadmium 5 <1.2 <.1 <.1 0.598 Chloride 250,000a 6,700,000 450,000 2,700,000 11,000,000 Chromium 100 8.52 9.66 1.33 4.54 Copper 300 46.5 24.1 19.8 33.6 Cyanide 200 <4 Fluoride 4,000 36,000 Iron 5,000 <4 420 270 1,700 Lead 15 24 14.4 10.2 13 Manganese 800 1,000 888 362 1,250 Mercury 2 <0.2 <0.2 <0.2 <0.2 Nickel 100 12.2 14.7 5.06 13.8 Thallium 2 <0.34 Zinc 2,000 6,770 926 744 626 8,000,000 is acceptable. MCL is the maximum allowable concentration. Black space means the test was not conducted. ND means there was no detectible amount of contaminate present. As can be seen from the test data provided in Table 1 and the Analytica reports, the present filtration apparatus surprisingly removed a very large number of undesirable organic and inorganic contaminates. The plastic filter sheet material utilized is not known by those skilled in the art to remove these types of contaminates. The removal of these contaminates was completely unexpected. The waste water was sufficiently cleaned so that it could be discarded using the public waste water treatment, which avoided the very high cost of hazardous material treatment. Because the Frisco site was so successful, the CDOT installed 10 further locations, of which 8 are currently online. The new locations used an apparatus as shown in FIGS. 4A-4G. The filtration size was: #1 filter—5 mic #2 filter—1 mic #3 filter—0.5 mic #4 filter—0.2 mic #5 filter—0.2 mic The #1 filter is the top most filter and the #5 filter is the lowest. The filter material is a heat welded polyester sheet. The CDOT sites used an Alaadin power washer model # T416, 3,000 psi, 4 gallon per minute, 220v, which is propane or natural gas heated. The CDOT bays range in size to accommodate from 3 to 16 vehicles and equipment. CDOT also recently tested the chloride concentration in five of the locations using chloride strips and the results are shown in Table 2. 8000 ppm of chloride is considered acceptable. However, the lower the chloride level the better. TABLE 2 Date and Location Pre-Filter Post-Filter Boomfield Location Dec. 22, 2004 NP Strip 4.8; 1,517 ppm Dec. 29, 2004 Strip 8.6; >6,211 ppm Strip 6.2; 2,766 ppm Derby Location Dec. 1, 2004 NP Strip 7.0; 3,870 ppm Dec. 9, 2004 Strip 1.8; 308 ppm1 Strip 0.8; <257 ppm Dec. 22, 2004 NP Strip 1.8; 308 ppm Dec. 29, 2004 NP Strip 3.3; 804 ppm Havana Location Nov. 23, 2004 Strip 7.8; 5,608 ppm Strip 1.6; 257 ppm Dec. 10, 2004 Strip 8.2; >6,211 ppm Strip 8.0; 6,200 ppm Dec. 22, 2004 NP Strip 7.7; 5,347 ppm Dec. 29, 2004 NP Strip 4.8; 1,571 ppm Knox Ct. Location Dec. 29, 2004 NP Strip 4.8; 1,571 ppm Valley Hwy Dec. 12, 2004 NP Strip 1.8; 308 ppm 1The filtration system was cleaned out and filled with fresh water just before the test, which explains the low pre-filter chloride concentration. NP = Not Performed. The test data demonstrates that the present filtration system is capable of cleaning up the CDOT water run-off to such a degree that it is no longer considered hazardous material. The filtrated water can simply be discarded using public waste treatment facilities saving the CDOT many thousands of dollars. Furthermore, the present filtration systems can be run as closed systems so that no waste water needs to be discarded. While the claimed invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one of ordinary skill in the art that various changes and modifications can be made to the claimed invention without departing from the spirit and scope thereof. | <SOH> 2. BACKGROUND OF THE INVENTION <EOH>There have been many attempts to filter water. One such conventional recycling apparatus is sold commercially under the Cyclonator™ name. A description can be found on the internet at www.cyclonator.com. This system uses numerous hoses to and from a specially designed washing platform, an additional separate filtering tank to remove larger debris and oils, a special holding tank, and two vacuum canister type filters that require expensive filters. This recycling apparatus provides no visual monitoring ability except for vacuum gauges, has no pH monitoring nor automatic adjustment capability, and the location of the unit has to be in close proximity to the wash platform and the power washer. Furthermore, the filtering apparatus is difficult to maintain, requires a large area of space and numerous extra equipment at additional cost. Moreover, the vacuum or pressure used to force the wash solution through a filter can undesirably force dirt through filters. There are many other systems that use pressure or vacuum, including those from Cyclonator standard filtration weir, www.cyclonator.com; Powder-X Pretreatment Station, Powder-X Coating Systems, Inc., www.powder-x-.com; Rapid Pretreatment Station, www.rapidengineering.com; PKG Equipment, Inc., www.pkgeguipment.com; Water Treatment Tech Equipment, MFG.; Pressure Island; Arkal Filtration; ADF-Liquid Filtration; Kemco Systems; and Tiger Enterprises, 39126 Alston Ave., Zephyrhills, Fl 33542. Two open water filtration systems, CFS3 and CMAFU-2 are commercially sold by HydroEngineering, disclosed at www.hydroblaster.com. However, in these systems the filtered water is not continuously filtered through the filter media and there is only one filter media. While there are other filtering systems disclosed on the website which refer to circulation of water for multiple passes through polishing media (see description of Model ACF3) this appears to be a closed system since hydrobiodigesters must be utilized. Furthermore, conventional water purification systems for producing potable water from non-potable water are complicated, difficult to use and require extensive maintenance. An example of such a system utilizes reverse osmosis. There is a need for an improved water filtering apparatus that does not require a vacuum or pressure pumps, provides easy visual inspection of the filters during operation, is easy to maintain and operate, and can be scaled to any size operation. There is also need for a simplified water purification system for producing potable water from non-potable water. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>FIG. 1A illustrates a side view of the water filtering apparatus; FIG. 1B illustrates a view of a filter assembly; FIG. 2A illustrates a view of a horse water filtering apparatus; FIG. 2B illustrates a view of a horse water filtering apparatus; FIG. 3A illustrates a view of a potable water filtration system; FIG. 3B illustrates a view of a magnetic filter mount; FIG. 3C illustrates a view of an activated material impregnated flat roll Filter material; FIG. 4A illustrates a view of a water filtering apparatus and spray washer; FIG. 4B illustrates a partial cut-away side view of a water filtering apparatus; FIGS. 4C through 4E illustrate views of a filter assembly; FIG. 4F illustrates a clamp for mounting a filter material in a filter assembly; and FIG. 4G illustrates a basin for collecting filtered solution. detailed-description description="Detailed Description" end="lead"? | 20050121 | 20060711 | 20051020 | 66563.0 | 0 | POPOVICS, ROBERT J | METHODS AND APPARATUSES FOR FILTERING WATER | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,038,654 | ACCEPTED | Microcontroller with synchronised analog to digital converter | A microcontroller is provided, which includes a control unit (UC), at least one digital to analog converter (DAC) as a peripheral of the said control unit, and a buffer register located between the said control unit and the said converter, receiving data and a first command to transfer the said data from the said control unit. The microcontroller includes means of synchronisation of the said converter including a register inserted between the said buffer register and the said converter, the said register receiving a second transfer command independent of the said control unit. | 1. A microcontroller comprising: a control unit (UC), at least one digital to analog converter (DAC) as a peripheral of the said control unit, a buffer register located between the said control unit and the said converter, receiving data and a first command to transfer the said data from the said control unit, and means of synchronisation of the said converter including a register inserted between the said buffer register and the said converter, the said register receiving a second transfer command independent of the said control unit. 2. The microcontroller according to claim 1, wherein the said second transfer command is a hardware interrupt. 3. The microcontroller according to claim 2, wherein the said hardware interrupt is generated by at least one timer internal to the microcontroller. 4. The microcontroller according to claim 2, wherein the said hardware interrupt corresponds to at least one of the elements belonging to the group comprising: end of counting of a time base; an exit from a comparison at a pre-programmed time; an external signal associated with collection of the internal time; and an external signal generating a software interrupt. 5. The microcontroller according to claim 1, wherein the said synchronisation means also include a synchronisation block for the said register into which at least one synchronisation signal and the said first transfer command are input. 6. The microcontroller according to claim 1, wherein the said digital to analog converter processes N-bit words, and the control unit outputs the said data in the form of M-bit words, where M<N, and the said microcontroller comprises means for formatting an N-bit word from two M-bit words. 7. The microcontroller according to claim 6, wherein the said formatting means comprise means for extracting an N-bit word from two M-bit words, selecting either the N high order bits, or the N low order bits. 8. The microcontroller according to claim 6, wherein M=8 and N=10. 9. The microcontroller according to claim 1, wherein the said converter generates a predetermined wave shape. 10. The microcontroller according to claim 1, wherein the said converter outputs an analog signal to at least one of the elements belonging to the group containing: industrial logic controllers; power supplies; ballasts; household appliances; position slaving devices; electric motor control means. | CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority of French Application No. FR 04/00507, filed Jan. 20, 2004, not in English. FIELD OF THE INVENTION The field of the invention is electronic components, and particularly microcontrollers. More precisely, the invention relates to a microcontroller comprising one or several integrated analog to digital converters (ADC). The invention can be used in applications in all fields in which a process or a function including a microcontroller is required to generate variable analog voltage, particularly in the presence of strict time constraints. Thus, the invention is used for example in applications in industrial logic controllers, power supplies, ballasts, household appliances, position slaving devices or electric motor control means. BACKGROUND OF THE INVENTION A microcontroller is generally composed of a central control unit, data and program memories, and peripherals. For example, one peripheral might be a communication interface, another peripheral might be a timer, and yet another might be an analog to digital converter (ADC) or sometimes a digital to analog converter (DAC). At the moment few microcontrollers have an integrated DAC. Consequently, when there is no microcontroller with an integrated DAC, an external DAC has to be used controlled by a peripheral, the interface between the microcontroller and the DAC being made through a serial bus usually of the SPI (Serial Peripheral Interface) type, or the I2C (Inter Integrated Circuit) type, or directly in parallel. However, regardless of whether the DAC is integrated into the microcontroller or is external, time management by the central processing unit of this microcontroller is not very precise. Since the microcontroller usually manages real time, the execution of a program may be modified by hardware or software interrupts being introduced, processed asynchronously by the control unit. In the DAC, the beginning of the conversion is initiated by execution of an instruction in the control unit of the microcontroller, making a write in a buffer register. In order to generate an analog wave shape F(t) on the DAC output, the converter has to be programmed so that it converts the value F(n) at precise instants ta. This technique is described in more detail later, with reference to FIGS. 1A, 1B and 2. One major disadvantage of systems described according to prior art is that the conversions are not made at precise instants, with the control unit triggering the conversion at the DAC. The control unit is configured to deal with interrupts, consequently it delays real time instructions. SUMMARY OF THE INVENTION The main purpose of an embodiment of the invention is to overcome this disadvantage of prior art. More precisely, one purpose of an embodiment of the invention is to provide a synchronisation interface used to make a digital to analog conversion at a precise instant, regardless of the internal activity of the microcontroller. Another purpose of an embodiment of the invention is to avoid the need for means external to the microcontroller and therefore to integrate such a synchronisation interface into a microcontroller. Another purpose of an embodiment of the invention is to provide such an interface that is easy to implement, while remaining inexpensive. Yet another purpose of an embodiment of the invention is to obtain a variable analog voltage as a function of time and respecting a particular wave shape. These objectives and others that will become clear later, are achieved using a microcontroller comprising a control unit (UC), at least one digital to analog converter (DAC) as a peripheral of the said control unit, and a buffer register located between the said control unit and the said converter, receiving data and a first command to transfer the said data from the said control unit. According to an embodiment of the invention, such a microcontroller includes means of synchronisation of the said converter including a register inserted between the said buffer register and the said converter, the said register receiving a second transfer command independent of the said control unit. Thus, an embodiment of the invention is based on a quite new and innovative approach to the generation of an analog wave shape on the output from a digital to analog converter, synchronisation of the conversion no longer being managed by the control unit which avoids delays due to processing of interrupts. More precisely, the buffer register is controlled by the control unit, while the register inserted between the buffer register and the DAC is controlled by a transfer command independent of the control unit. Preferably, the second transfer command is a hardware interrupt. Advantageously, the hardware interrupt is generated by at least one timer internal to the microcontroller. Thus, the data transfer between the buffer register and the register inserted between the DAC and the buffer register is triggered by a pulse sent by the timer that manages the time precisely, and is not dependent on interrupts, giving pulses at precise instants. In particular, the hardware interrupt may correspond to: end of counting of a time base; an exit from a comparison at a pre-programmed time; an external signal associated with collection of the internal time; an external signal generating a software interrupt. In one advantageous embodiment, the synchronisation means also include a register synchronisation block into which at least one synchronisation signal and the first transfer command are input. These synchronisation signals originate from synchronisation sources and particularly timers. Preferably, the digital to analog converter processes N-bit words and the control unit outputs data in the form of M-bit words, where M<N, and the microcontroller includes means of formatting an N-bit word from two M-bit words. In particular, the formatting means include means of extracting an N-bit word from two M-bit words, selecting either the N high order bits, or the N low order bits. According to one advantageous embodiment of the invention, M=8 and N=10. Advantageously, the converter generates a predetermined wave shape. Preferably, the converter outputs an analog signal to at least one of the elements belonging to the group containing: industrial logic controllers; power supplies; ballasts; household appliances; position slaving devices; electric motor control means. BRIEF DESCRIPTION OF THE DRAWINGS Other characteristics and advantages of the invention will become clearer after reading the following description of a preferred embodiment given as a simple illustrative and non-limitative example, and the attached drawings among which: FIGS. 1A and 1B show a synchronisation interface for a digital to analog converter integrated into a microcontroller according to the state of the art; FIG. 2 shows an analog wave shape at the output from a DAC according to prior art as shown in FIG. 1A; FIGS. 3A and 3B show a synchronisation interface for a digital to analog converter integrated into a microcontroller according to the invention; FIG. 4 shows an analog wave shape at the output from the DAC shown in FIG. 3A; FIG. 5 shows an example of a DAC according to a particular embodiment of the invention; FIG. 6 shows a DAC like that shown in FIG. 5, in more detail; FIGS. 7A, 7B and 7C show the contents of the different registers of a DAC like that shown in FIG. 6. DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 1. General Principle The general principle of an embodiment of the invention is based on the insertion of a -register between a buffer register and a digital to analog converter, inside a microcontroller such that the buffer register is controlled by a signal controlled by the control unit of the microcontroller and such that the said register is controlled by a signal independent of the control unit. 2. Existing Technique The operation of a digital to analog converter (DAC) integrated into a microcontroller according to prior art is described with relation to FIG. 1A, in the case in which the microcontroller outputs data in the form of M-bit words and the DAC processes N-bit words, where N is less than or equal to M. Such a microcontroller with an integrated DAC usually comprises: a control unit 11; a buffer register RT 12. a digital to analog converter DAC 13; synchronisation sources 14, for example timers; data and program memory blocks (not shown). As already mentioned, the beginning of the conversion at the DAC 13 is initialised by execution of a write instruction addressed to RT, into the control unit UC 11 of the microcontroller. Therefore, the buffer register RT 12 receives data 15 from the control unit 11, along with a command to transfer these data, called the first transfer command 16. However, some instructions will be delayed because the execution of the program within the control unit 11 can be modified by the acceptance of hardware or software interrupts; the microcontroller will then no longer be able to precisely synchronise the digital to analog conversion. FIG. 1B shows another situation in which the microcontroller outputs data in the form of M-bit words and in which the DAC converts N-bit words, where N is greater than M. In this case, the microcontroller firstly includes the same elements as those described in FIG. 1A, namely a control unit 11, a buffer register RT, a digital to analog converter DAC 13, synchronisation sources 14, data and program memory blocks (not shown), but it also has an additional N bit register R 123 necessary to increase the size of the data bus to N bits. In this embodiment, the contents of the register RT are implemented on two registers RT 121 and RT 122 with size M. A word with size N is then built up in the register R 123, from two words with size M in registers RT 121 and 122. As mentioned above, the beginning of the conversion at the DAC 13 is initialised by execution of a write instruction addressed to register R 123, in the microcontroller control unit UC 11. Therefore the register R 123 receives a command to transfer these data, called the first transfer command 16, from the control unit 11. Thus as shown in FIG. 2, the digital to analog conversions are not done at precise instants ti (where i is a relative integer), but at instants ti+ei where ei is equal to a delay due to interrupts 25 managed by the control unit 11. Consequently, the shape of the analog wave F(t) at the output from the DAC is incorrect, since the DAC converts a digital value at instant tn+en and not at instant tn. 3. Embodiment of the Invention Case N<M FIG. 3A shows a synchronisation interface capable of eliminating inaccuracies in the digital to analog conversion within a microcontroller according to an embodiment of the invention, when the microcontroller outputs data in the form of M-bit words and the DAC converts N-bit words, where N is less than or equal to M. The microcontroller includes firstly elements shown in FIG. 1A; a control unit 31, a buffer register RT 32, a digital to analog converter 34, different synchronisation sources 36, data and program memory blocks and possibly other peripherals. According to the embodiment, a register R 33 inserted between the buffer RT 32 and the DAC 34, and a synchronisation block 35, are also integrated into the microcontroller. The purpose of the synchronisation block 35 is to assure that the digital to analog conversion is done at a precise instant, regardless of the internal activity of the microcontroller and particularly its control unit 31. To achieve this, the synchronisation block 35 receives synchronisation signals 37 from the control unit 31 or from synchronisation sources 36, and particularly timers, as input. These signals 37 are hardware interrupts, and may correspond to one of the following: end of counting of a time base that provides a periodic interrupt; an interrupt at a pre-programmed time (for example an exit from a comparison); an external signal generating a software interrupt; an external signal generating an interrupt associated with collection of the internal time. The synchronisation interface includes two conversion registers: the register R 33 directly connected to the DAC 34, for which the digital contents correspond to the analog value output from the DAC 34; the buffer register RT 32 for which the digital contents initially correspond to the future analog value. As for the system according to prior art described in FIG. 1A, the buffer register RT 32 receives data 38 and a command 39 to transfer these data called the first transfer command 39, from the control unit 31. The synchronisation block 35 is then used to control the final transfer of data between the buffer register RT 32 and the register R 33 using a second transfer command independent of the control unit 31. This transfer is actually done when a transition is detected in a synchronisation signal. In one preferred embodiment of the invention, the synchronisation signal is output from a timer. The data transfer between the buffer register RT 32 and the register 33 is then triggered by a pulse, the timer managing the time precisely and not dependently on interrupts, by outputting pulses at precise instants. Case N>M FIG. 3B shows the case in which the microcontroller outputs data in the form of M-bit words and in which the DAC processes N-bit words, where N is greater than M. In this case, the microcontroller has the same elements as those described in FIG. 3A. However, in this embodiment, the contents of register RT are stored in two registers RT 321 and RT 322 with size. M. A word with size N is then built up in register R from the two words with size M in registers RT 321 and RT 322. The means of formatting an N-bit word from two M-bit words are described in more detail below, with reference to FIG. 5. “DETAILED EXAMPLE” SECTION As described above, the synchronisation block 35 receives input synchronisation signals 37 from the control unit 31 or synchronisation sources 36, and particularly timers. This synchronisation block 35 is used to control final transfer of data between buffer registers RT 321 and RT 322 and register R 33, using a second transfer command independent of the control unit 31. This transfer is made as soon as a transition is detected in a synchronisation signal. 4. Implementing an Embodiment of the Invention As shown in FIG. 4, digital to analog conversions are then made at precise instants ti, the conversion being synchronised with an event originating from the timer (or another synchronisation source) and not, as in prior art, from the control unit, that delays instructions as a function of interrupts. In another embodiment, the synchronisation signal originates from an interrupt at a pre-programmed time corresponding to the output from a comparison. The value t1 is programmed in a comparison register, and the value F(t1) is programmed in the buffer conversion registers RT 321 and 322. When the interrupt corresponding to t1 takes place, the value t2 is programmed in the comparison register and the value F(t2) is programmed in the buffer conversion registers RT 321 and 322. When the interrupt corresponding to ti-1 takes place, the value t1 is programmed in the comparison register and the value F(ti) is programmed in the buffer conversion registers RT 321 and 322, where i is a relative integer. This summarises a wave shape F(ti). Obviously, the invention is not limited to synchronisation signals internal to the microcontroller, and synchronisation sources 36 may also be internal or external to the microcontroller. Therefore, an embodiment of the invention eliminates uncertainties about conversion times due to the real time activity of the microcontroller and generates an analog wave shape with less distortion. 5. DETAILED EXAMPLE We will now show an example of a digital to analog converter according to a particular embodiment of the invention, with reference to FIG. 5. For further details refer to the complete diagram for such a DAC, shown in FIGS. 6, 7A, 7B and 7C and described in the appendix. In this particular embodiment, the synchronisation of the DAC is implemented in an AVR type 8-bit (brand held by the holder of this patent application) microcontroller. This type of microcontroller may be used particularly in lighting systems. The control unit of such a microcontroller outputs data in the form of 8 bit words, while the DAC processes 10 bit words in this embodiment. Consequently, it is decided to implement the register R and the buffer register RT on two 8-bit registers. These two pairs of registers widen the data bus from 8 to 10 bits and perform the synchronisation function. Since the register R is directly connected to the DAC, it is important to format the contents of the register R implemented on two 8-bit registers (the register DACSH and the register DACSL) to form a 10-bit word input to the DAC. Preferably, the contents of the register R are formatted by choosing: either to keep the 10 high order bits of the register R corresponding to the 8 bits of the DACSH register and the first 2 bits of the DACSL register, to form a 10 bit “DAC High bits” word; or to keep the 10 low order bits of register R corresponding to the last 2 bits of the DACSH register and the 8 bits of the DACSL register to form a 10 bit “DAC Low bits” word; these 10 bits being selected among the 16 bits (two 8 bit words) combinationally at the output from the DACSH and DACSL registers. The digital to analog converter interface includes five 8 bit registers, namely the DACH register and the DACL register (corresponding to the buffer register RT), the DACSH register and the DACSL register (corresponding to the register R) and the DACON register. An analog wave shape F(t) is obtained at the output from the DAC. The DACON (Digital-to-Analog Conversion Control Register) register is used for checking the digital to analog conversion. It enables configuration of the DAC by choosing whether to enable or disable synchronisation, selection of the interrupt source (for example an external signal, an exit from comparison, or an end of counting of an external or internal time base, etc.) or selection of the 10 bit word corresponding to the high order bits (DAC High bits) or the low order bits (DAC Low bits). Therefore, this type of DAC can process N-bit words, even if the control unit outputs data in the form of M-bit words, where M is less than N, by combining several M-bit words. In particular, many applications use 8 bit words (M=8). This invention is particularly useful for any application that has to generate a variable voltage with strict time constraints, for example such as a position slaving application, an electric motor control application, a welding station application, an instrumentation application, or a power supply application. 6. Appendices Operation: The Digital Analog Converter (DAC) shown in FIG. 6 generates an analog signal as a function of the contents of DAC write registers. It is possible to update the DAC input values taking account of the different events originating from “triggers”, in order to have a precise control sampling frequency. Control Registers: The DAC is controlled by three dedicated registers: the Digital to Analog Conversion Control Register (DACON), used for configuration of the DAC and shown in FIG. 7A; the DACH and DACL registers, used for data to be converted and shown in FIGS. 7B and 7C. The DACON register (FIG. 7A): Bit 7—DAATE (DAC Auto Trigger Enable Bit). Set this bit to ‘1’ to update the DAC input value on a rising front of the trigger, also called the synchronisation signal, selected from the DATS2, DATS1, DATS0 bits in the DACON register. Leave it equal to ‘0’ to automatically update the DAC input when a value is written in the DACH register. Bit 6:4—DATS2, DATS1, DATS0 (DAC Trigger Selection bits) These bits are only necessary if the DAC is working in “auto trigger” mode, in other words when the DAATE bit is used. As shown in table 1, the three DATS2:0 bits are used to select the interrupt that will trigger an update to the DAC input values. The update will be triggered by a rising front in a selected interrupt signal, regardless of whether or not the interrupt is enabled. TABLE 1 Selection of the Trigger Event (DAC Auto Trigger Source) DATS2 DATS1 DATS0 Description 0 0 0 Analog comparator 0 0 0 1 Analog comparator 1 0 1 0 External interrupt request 0 0 1 1 Comparison Timer/Counter 0, value A 1 0 0 Timer/Counter 0, overrun 1 0 1 Comparison Timer/Counter 0, value B 1 1 0 Timer/Counter 1, overrun 1 1 1 Comparison Timer/Counter 0, collection event Bit 2—DALA (Digital to Analog Left Adjust) Set this bit equal to ‘1’ to write data to be entered into the DAC from the left. Set it equal to ‘0’ to enter data from the right. The DALA bit has an incidence on the configuration of DAC write registers. When the value his bit is modified, the output from the DAC is modified at the time of the next write in the DACH register. Bit 1—DAOE (Digital to Analog Output Enable Bit) Set this bit equal to ‘1’ to output the result of the conversion on the external DA pin, and leave it equal to ‘0’ to keep the result inside the DAC. Bit 0—DAEN (Digital to Analog Enable bit) Set this bit equal to ‘1’ to enable the digital to analog converter. Set it equal to ‘0’ to disable it. Converter input registers: DACH and DACL The DACH and DACL registers contain the value to be converted. Writing into DACL prevents updating the value to be converted until the DACL register has been updated. Thus, the normal means of writing a value to be converted is firstly to write DACL and then DACH. The input value can be adjusted from the left, to make it easy to work with 8-bit words. Thus, the value of the DAC can be updated simply by writing into the DACH register. The contents of the DACH register depend on the configuration selected from the DALA bit. When this DALA bit is equal to ‘0’, as shown in FIG. 7B, the first point is to write data to be input into the DAC from the right. Therefore, the first 8 data bits are written into the DACL register and the last 2 bits are written into the DACH register. When this DALA bit is equal to ‘1’ as shown in FIG. 7C, the data to be input into the DAC are written from the left. Therefore, the first 8 data bits are written into the DACH register and the last 2 bits are written into the DACL register. The DAC must update two registers to convert 10-bit words. To prevent intermediate values, the DAC input values that are actually converted into an analog signal are stored in a register that cannot be accessed by program, and is not shown (corresponding to the DACSH and DACSL registers in FIG. 5). In normal mode, the value to be converted is updated when the DACH register is written. If the DAATE bit is set equal to ‘1’, the DAC input values will be updated when the event takes place on the trigger, selected from the DATS2:0 bits, immediately after the DACH register has been written. If the DAATE bit in the DACON register is set equal to ‘0’, the DAC is in an automatic update mode. Writing in the DACH register automatically updates the DAC input values with the contents of the DACH and DACL registers. This means that changing the contents of the DACL register has no effect on the output from the DAC until the DACH register has been updated. Thus, to work with 10-bit words, the first step is to write into the DACL register before writing into the DACH register. When working with 8-bit words, writing into DACH will cause the DAC to be updated. Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>A microcontroller is generally composed of a central control unit, data and program memories, and peripherals. For example, one peripheral might be a communication interface, another peripheral might be a timer, and yet another might be an analog to digital converter (ADC) or sometimes a digital to analog converter (DAC). At the moment few microcontrollers have an integrated DAC. Consequently, when there is no microcontroller with an integrated DAC, an external DAC has to be used controlled by a peripheral, the interface between the microcontroller and the DAC being made through a serial bus usually of the SPI (Serial Peripheral Interface) type, or the I2C (Inter Integrated Circuit) type, or directly in parallel. However, regardless of whether the DAC is integrated into the microcontroller or is external, time management by the central processing unit of this microcontroller is not very precise. Since the microcontroller usually manages real time, the execution of a program may be modified by hardware or software interrupts being introduced, processed asynchronously by the control unit. In the DAC, the beginning of the conversion is initiated by execution of an instruction in the control unit of the microcontroller, making a write in a buffer register. In order to generate an analog wave shape F(t) on the DAC output, the converter has to be programmed so that it converts the value F(n) at precise instants t a . This technique is described in more detail later, with reference to FIGS. 1A, 1B and 2 . One major disadvantage of systems described according to prior art is that the conversions are not made at precise instants, with the control unit triggering the conversion at the DAC. The control unit is configured to deal with interrupts, consequently it delays real time instructions. | <SOH> SUMMARY OF THE INVENTION <EOH>The main purpose of an embodiment of the invention is to overcome this disadvantage of prior art. More precisely, one purpose of an embodiment of the invention is to provide a synchronisation interface used to make a digital to analog conversion at a precise instant, regardless of the internal activity of the microcontroller. Another purpose of an embodiment of the invention is to avoid the need for means external to the microcontroller and therefore to integrate such a synchronisation interface into a microcontroller. Another purpose of an embodiment of the invention is to provide such an interface that is easy to implement, while remaining inexpensive. Yet another purpose of an embodiment of the invention is to obtain a variable analog voltage as a function of time and respecting a particular wave shape. These objectives and others that will become clear later, are achieved using a microcontroller comprising a control unit (UC), at least one digital to analog converter (DAC) as a peripheral of the said control unit, and a buffer register located between the said control unit and the said converter, receiving data and a first command to transfer the said data from the said control unit. According to an embodiment of the invention, such a microcontroller includes means of synchronisation of the said converter including a register inserted between the said buffer register and the said converter, the said register receiving a second transfer command independent of the said control unit. Thus, an embodiment of the invention is based on a quite new and innovative approach to the generation of an analog wave shape on the output from a digital to analog converter, synchronisation of the conversion no longer being managed by the control unit which avoids delays due to processing of interrupts. More precisely, the buffer register is controlled by the control unit, while the register inserted between the buffer register and the DAC is controlled by a transfer command independent of the control unit. Preferably, the second transfer command is a hardware interrupt. Advantageously, the hardware interrupt is generated by at least one timer internal to the microcontroller. Thus, the data transfer between the buffer register and the register inserted between the DAC and the buffer register is triggered by a pulse sent by the timer that manages the time precisely, and is not dependent on interrupts, giving pulses at precise instants. In particular, the hardware interrupt may correspond to: end of counting of a time base; an exit from a comparison at a pre-programmed time; an external signal associated with collection of the internal time; an external signal generating a software interrupt. In one advantageous embodiment, the synchronisation means also include a register synchronisation block into which at least one synchronisation signal and the first transfer command are input. These synchronisation signals originate from synchronisation sources and particularly timers. Preferably, the digital to analog converter processes N-bit words and the control unit outputs data in the form of M-bit words, where M<N, and the microcontroller includes means of formatting an N-bit word from two M-bit words. In particular, the formatting means include means of extracting an N-bit word from two M-bit words, selecting either the N high order bits, or the N low order bits. According to one advantageous embodiment of the invention, M=8 and N=10. Advantageously, the converter generates a predetermined wave shape. Preferably, the converter outputs an analog signal to at least one of the elements belonging to the group containing: industrial logic controllers; power supplies; ballasts; household appliances; position slaving devices; electric motor control means. | 20050119 | 20080401 | 20051110 | 67150.0 | 2 | TRAN, VINCENT HUY | MICROCONTROLLER WITH SYNCHRONISED ANALOG TO DIGITAL CONVERTER | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,688 | ACCEPTED | Systems for negotiating buffer size and attribute characteristics in media processing systems that create user-defined development projects | In one embodiment, a system receives an indication to generate a filter graph representing a user-defined development project. Media sources that are to be used in the user-defined development project are identified and a programming grid is establishing that incorporates a user's editing instructions. A matrix switch filter is generated based, at least in part, on the programming grid. The filter graph is assembled and comprises a plurality of individual filters. Buffer size and attribute characteristics are negotiated between an input/output of the matrix switch filter and an input/output of adjacent filters. Negotiated buffers are utilized to communicate media content between the matrix switch filter and adjacent filters by sharing a common buffer between inputs and outputs. | 1. A computing device comprising: one or more processors; one or more computer-readable media; computer-readable instructions embodied on the one or more computer-readable media which, when executed by the one or more processors, implement a method comprising: receiving an indication to generate a filter graph representing a user-defined development project; identifying media sources that are to be used in the user-defined development project; based, at least in part, on the identified media sources, exposing sources, transform filters and rendering filters configured for use in the user-defined development project; establishing a programming grid that incorporates a user's editing instructions; generating a matrix switch filter based, at least in part, on the programming grid, wherein the programming grid identifies which matrix switch filter inputs are to be coupled to which matrix switch filter outputs at particular project times; assembling the filter graph representing the user-defined development project, wherein the filter graph comprises a plurality of individual filters including said matrix switch filter, transform filters and rendering filters; and instructing filters of the filter graph to negotiate buffer size and attribute characteristics between adjacent filters, wherein negotiated buffers are utilized to communicate media content between the matrix switch filter and adjacent filters by sharing a common buffer between inputs and outputs. 2. The computing device of claim 1, wherein the method further comprises: modifying input/output associations between filters of the development project based at least in part on the negotiation. 3. The computing device of claim 2, wherein input/output associations are communicative connections through one or more buffers. 4. The computing device of claim 1, wherein the act of assembling comprises providing a separate buffer for each input and output of each filter within the project, and wherein the method further comprises after and responsive to said act of negotiating, replacing at least a pair of separate adjacent buffers with a single buffer shared therebetween. 5. The computing device of claim 1, wherein the method further comprises attempting, with the matrix switch filter, to be an allocator for buffers shared with each of its input(s) and output(s). 6. The computing device of claim 5, wherein the method further comprises, in an event the matrix switch filter cannot be an allocator for one or more of its input(s) or output(s), not sharing a common buffer between such input(s) and output(s) and filters coupled thereto. 7. The computing device of claim 6, wherein the method further comprises using memory copy operations to communicate information from the matrix switch filter to a downstream filter in an event the matrix switch filter cannot be an allocator for a matrix switch filter output associated with said downstream filter. 8. A computing device comprising: one or more processors; one or more computer-readable media; computer-readable instructions embodied on the one or more computer-readable media which, when executed by the one or more processors, implement a method comprising: providing one or more processing chains that can be utilized to implement a user-defined development project, wherein individual processing chains comprise a plurality of filters, individual filters comprising one of at least a source filter, a transform filter or a render filter; providing a matrix switch, coupled to the one or more processing chains, to recursively pass content received from the one or more processing chains through one or more filters to implement the development project; and negotiating, with the matrix switch, buffer size and attributes between the matrix switch and adjacent filters, wherein the negotiated buffers are utilized to communicate media content between the matrix switch and adjacent filters without requiring a buffer copy operation. 9. The computing device of claim 8, wherein each of the filters comprising the one or more processing chains attempts to negotiate buffer size and attribute characteristics in order to facilitate a shared buffer for communicating information between the filters of the processing chain. 10. The computing device of claim 9, wherein the filters establish shared buffers between an input of one filter and the output of an upstream filter upon negotiating mutually acceptable buffer size and attribute characteristics. 11. The computing device of claim 8, wherein the method further comprises establishing the development project using a render engine that is exposed from an operating system executing on a computing system implementing the development system. 12. The computing device of claim 11, wherein the method further comprises: using the render engine to facilitate negotiation between filters of the processing chains for buffer size and attribute requirements, and using the render engine to establish a shared buffer for communicating content between filters when an agreement as to the requirements is achieved. 13. The computing device of claim 8, wherein the method further comprises using the matrix switch to negotiate to be an allocator of buffers between the matrix switch and any filter coupled to its input and output to facilitate communication between the matrix switch and external filters as well as between its input(s) and output(s), without the need for a memory copy operation. 14. The computing device of claim 13, wherein the method further comprises, in an event the matrix switch is not able to be an allocator of a buffer for an output of the matrix switch, using a memory copy operation to communicate with a downstream filter associated with that matrix switch output. 15. A computing device comprising: one or more processors; one or more computer-readable media; computer-readable instructions embodied on the one or more computer-readable media which, when executed by the one or more processors, implement a method comprising: providing a matrix switch object; providing a dynamically determined number of matrix switch object inputs to receive content from one or more processing chains; providing a dynamically determined number of matrix switch object outputs; selectively coupling one or more of the dynamically determined inputs to one or more of the dynamically determined outputs; and negotiating, using the matrix switch object, with filters coupled to each of the dynamically determined inputs and outputs for buffer size and attribute requirements to facilitate communication between filters and within the matrix switch object using a shared buffer of agreed upon size and attribute characteristics. 16. The computing device of claim 15, wherein the method further comprises, in an event the matrix switch object cannot negotiate an agreed upon buffer size and attribute characteristics between an input/output and a filter coupled to the input/output, communicating with the input/output using a memory copy operation. 17. The computing device of claim 16, wherein the method further comprises, in an event an input/output coupling the filter to the input/output of the matrix switch object each have an independent buffer, communicating between the filter and the matrix switch object by copying content from one buffer to another buffer. 18. The computing device of claim 15, wherein the method further comprises communicating between the input/output of the matrix switch object and any other input/output, internal or external to the matrix switch object, using a memory copy operation. 19. The computing device of claim 16, wherein the method further comprises, in an event an input/output of the matrix switch object and an input/output of a filter coupled to the input/output of the matrix switch object do agree upon buffer size and attribute requirements, communicating between the filter and the matrix switch object through a shared buffer coupling the input/output of the filter to the input/output of the matrix switch object. 20. The computing device of claim 19, wherein the method further comprises communicating between the input/output of the matrix switch object and a second input/output of the matrix switch object through a shared buffer, unless the second input/output does not adhere to the agreed upon buffer size and attribute requirements. | RELATED APPLICATIONS This application is related to the following commonly-filed U.S. Pat. No. Applications, all of which are commonly assigned to Microsoft Corp., the disclosures of which are incorporated by reference herein: Application Ser. No. 09/731,560, entitled “An Interface and Related Methods for Reducing Source Accesses in a Development System”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-643US; Application Ser. No. 09/732,084, entitled “A System and Related Interfaces Supporting the Processing of Media Content”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-629US; Application Ser. No. 09/731,490, entitled “A System and Related Methods for Reducing Source Filter Invocation in a Development Project”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS163US; Application Ser. No. 09/731,529, entitled “A System and Related Methods for Reducing the Instances of Source Files in a Filter Graph”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-633US; Application Ser. No. 09/732,087, entitled “An Interface and Related Methods for Dynamically Generating a Filter Graph in a Development System”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-634US; Application Ser. No. 09/732,090, entitled “A System and Related Methods for Processing Audio Content in a Filter Graph”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-639US; Application Ser. No. 09/732,085, entitled “A System and Methods for Generating an Managing Filter Strings in a Filter Graph”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-642US; Application Ser. No. 09/731,491, entitled “Methods and Systems for Processing Media Content”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-640US; Application Ser. No. 09/731,563, entitled “Systems for Managing Multiple Inputs and Methods and Systems for Processing Media Content”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-635US; Application Ser. No. 09/731,892, entitled “Methods and Systems for Implementing Dynamic Properties on Objects that Support Only Static Properties”, naming Daniel J. Miller and David Maymudes as inventors, and bearing attorney docket number MS1-638US; Application Ser. No. 09/732,089, entitled “Methods and Systems for Efficiently Processing Compressed and Uncompressed Media Content”, naming Daniel J. Miller and Eric H. Rudolph as inventors, and bearing attorney docket number MS1-630US; Application Ser. No. 09/731,581, entitled “Methods and Systems for Effecting Video Transitions Represented By Bitmaps”, naming Daniel J. Miller and David Maymudes as inventors, and bearing attorney docket number MS1-637US; TECHNICAL FIELD This invention generally relates to processing media content and, more particularly, to a system and related interfaces facilitating the processing of media content. BACKGROUND Recent advances in computing power and related technology have fostered the development of a new generation of powerful software applications. Gaming applications, communications applications, and multimedia applications have particularly benefited from increased processing power and clocking speeds. Indeed, once the province of dedicated, specialty workstations, many personal computing systems now have the capacity to receive, process and render multimedia objects (e.g., audio and video content). While the ability to display (receive, process and render) multimedia content has been around for a while, the ability for a standard computing system to support true multimedia editing applications is relatively new. In an effort to satisfy this need, Microsoft Corporation introduced a multimedia processing architecture that supports editing functions. An example of this architecture is presented in a U.S. Pat. No. 5,913,038 issued to Griffiths and commonly owned by the assignee of the present invention, the disclosure of which is expressly incorporated herein by reference. In the '038 patent, Griffiths introduced the filter graph manager, exposed to higher-level, user interface application(s), which enabled a user to graphically construct a multimedia processing project by piecing together a collection of filters offered by the filter graph manager. The filter graph manager controls the data structure of the filter graph and the way data moves through the filter graph. The filter graph manager provides a set of component object model (COM) interfaces for communication between a filter graph and its application. Filters of a filter graph architecture are preferably implemented as COM objects, each implementing one or more interfaces, each of which contains a predefined set of functions, called methods. Methods are called by an application program or other component objects in order to communicate with the object exposing the interface. The application program can also call methods or interfaces exposed by the filter graph manager object. Filter graphs work with data representing a variety of media (or non-media) data types, each type characterized by a data stream that is processed by the filter components comprising the filter graph. A filter positioned closer to the source of the data is referred to as an upstream filter, while those further down the processing chain is referred to as a downstream filter. For each data stream that the filter handles it exposes at least one virtual pin (i.e., distinguished from a physical pin such as one might find on an integrated circuit). A virtual pin can be implemented as a COM object that represents a point of connection for a unidirectional data stream on a filter. Input pins represent inputs and accept data into the filter, while output pins represent outputs and provide data to other filters. Each of the filters include at least one memory buffer, wherein communication of the media stream between filters is accomplished by a series of “copy” operations from one filter to another. As introduced in Griffiths, a filter graph has three different types of filters: source filters, transform filters, and rendering filters. A source filter is used to load data from some source; a transform filter processes and passes data; and a rendering filter renders data to a hardware device or other locations (e.g., saved to a file, etc.). An example of a filter graph for a simplistic media rendering process is presented with reference to FIG. 1. FIG. 1 graphically illustrates an example filter graph for rendering media content. As shown, the filter graph 10 is comprised of a plurality of filters 124-22, which read, process (transform) and render media content from a selected source file. As shown, the filter graph includes each of the types of filters described above, interconnected in a linear fashion. Products utilizing the filter graph have been well received in the market as it has opened the door to multimedia editing using otherwise standard computing systems. It is to be appreciated, however, that the construction and implementation of the filter graphs are computationally intensive and expensive in terms of memory usage. Even the most simple of filter graphs requires and abundance of memory to facilitate the copy operations required to move data between filters. Complex filter graphs can become unwieldy, due in part to the linear nature of prior art filter graph architecture. Moreover, it is to be appreciated that the filter graphs themselves consume memory resources, thereby compounding the issue introduced above. Thus, what is required is a filter graph architecture which reduces the computational and memory resources required to support even the most complex of multimedia projects. Indeed, what is required is a dynamically reconfigurable multimedia editing system and related methods, unencumbered by the limitations described above. Just such a system and methods are disclosed below. SUMMARY In one embodiment, a system receives an indication to generate a filter graph representing a user-defined development project. Media sources that are to be used in the user-defined development project are identified and a programming grid is establishing that incorporates a user's editing instructions. A matrix switch filter is generated based, at least in part, on the programming grid. The filter graph is assembled and comprises a plurality of individual filters. Buffer size and attribute characteristics are negotiated between an input/output of the matrix switch filter and an input/output of adjacent filters. Negotiated buffers are utilized to communicate media content between the matrix switch filter and adjacent filters by sharing a common buffer between inputs and outputs. BRIEF DESCRIPTION OF THE DRAWINGS The same reference numbers are used throughout the figures to reference like components and features. FIG. 1 is a graphical representation of a conventional filter graph representing a user-defined development project. FIG. 2 is a block diagram of a computing system incorporating the teachings of the described embodiment. FIG. 3 is a block diagram of an example software architecture incorporating the teachings of the described embodiment. FIG. 4 is a graphical illustration of an example software-enabled matrix switch, according to an exemplary embodiment. FIG. 5 is a graphical representation of a data structure comprising a programming grid to selectively couple one or more of a scalable plurality of input pins to a scalable plurality of output pins of the matrix switch filter, in accordance with one aspect of the described embodiment. FIG. 6 is a graphical illustration denoting shared buffer memory between filters, according to one aspect of the described embodiment. FIG. 7 is a flow chart of an example method for generating a filter graph, in accordance with one aspect of the described embodiment. FIG. 8 is a flow chart of an example method for negotiating buffer requirements between at least two adjacent filters, according to one aspect of the described embodiment. FIG. 9 graphically illustrates an overview of a process that takes a user-defined editing project and composites a data structure that can be used to program the matrix switch. FIG. 10 graphically illustrates the project of FIG. 9 in greater detail. FIG. 11 shows an exemplary matrix switch dynamically generated in support of the project developed in FIGS. 9 and 10, according to one described embodiment. FIG. 12 illustrates a graphic representation of an exemplary data structure that represents the project of FIG. 10, according to one described embodiment. FIGS. 13-18 graphically illustrate various states of a matrix switch programming grid at select points in processing the project of FIGS. 9 and 10 through the matrix switch, in accordance with one described embodiment. FIG. 19 is a flow chart of an example method for processing media content, in accordance with one described embodiment. FIG. 20 illustrates an example project with a transition and an effect, in accordance with one described embodiment. FIG. 21 shows an exemplary data structure in the form of a hierarchical tree that represents the project of FIG. 20. FIGS. 22 and 23 graphically illustrate an example matrix switch programming grid associated with the project of FIG. 20 at select points in time, according to one described embodiment. FIG. 24 shows an example matrix switch dynamically generated and configured as the grid of FIGS. 22 and 23 was being processed, in accordance with one described embodiment. FIG. 25 shows an exemplary project in accordance with one described embodiment. FIG. 26 graphically illustrates an example audio editing project, according to one described embodiment. FIG. 27 depicts an example matrix switch programming grid associated with the project of FIG. 26. FIG. 28 shows an example matrix switch dynamically generated and configured in accordance with the programming grid of FIG. 27 to perform the project of FIG. 26, according to one described embodiment. FIG. 29 illustrates an exemplary media processing project incorporating another media processing project as a composite, according to yet another described embodiment. FIG. 30 graphically illustrates an example data structure in the form of a hierarchical tree structure that represents the project of FIG. 29. FIGS. 31-36 graphically illustrate various matrix switch programming grid states at select points in generating and configuring the matrix switch to implement the media processing of FIG. 29. FIG. 38 illustrates an example matrix switch suitable for use in the media processing project of FIG. 29, according to one described embodiment. FIG. 38a graphically illustrates an example data structure in the form of a hierarchical tree structure that represents a project that is useful in understanding composites in accordance with the described embodiments. FIG. 39 is a flow diagram that describes steps in a method in accordance with one described embodiment. DETAILED DESCRIPTION Application Ser. No. 09/732,372, entitled “Methods and Systems for Mixing Digital Audio Signals”, naming Eric H. Rudolph as inventor, and bearing attorney docket number MS1-636US; and Application Ser. No. 09/732,086, entitled “Methods and Systems for Processing Multi-media Editing Projects”, naming Eric H. Rudolph as inventor, and bearing attorney docket number MS1-641US. Various described embodiments concern an application program interface associated with a development system. According to one example implementation, the interface is exposed to a media processing application to enable a user to dynamically generate complex media processing tasks, e.g., editing projects. In the discussion herein, aspects of the invention are developed within the general context of computer-executable instructions, such as program modules, being executed by one or more conventional computers. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the invention may be practiced with other computer system configurations, including hand-held devices, personal digital assistants, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. In a distributed computer environment, program modules may be located in both local and remote memory storage devices. It is noted, however, that modification to the architecture and methods described herein may well be made without deviating from spirit and scope of the present invention. Moreover, although developed within the context of a media processing system paradigm, those skilled in the art will appreciate, from the discussion to follow, that the application program interface may well be applied to other development system implementations. Thus, the media processing system described below is but one illustrative implementation of a broader inventive concept. Example System Architecture FIG. 2 illustrates an example of a suitable computing environment 200 on which the system and related methods for processing media content may be implemented. It is to be appreciated that computing environment 200 is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the media processing system. Neither should the computing environment 200 be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary computing environment 200. The media processing system is operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with the media processing system include, but are not limited to, personal computers, server computers, thin clients, thick clients, hand-held or laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. In certain implementations, the system and related methods for processing media content may well be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The media processing system may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices. In accordance with the illustrated example embodiment of FIG. 2 computing system 200 is shown comprising one or more processors or processing units 202, a system memory 204, and a bus 206 that couples various system components including the system memory 204 to the processor 202. Bus 206 is intended to represent one or more of any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, and a processor or local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnects (PCI) buss also known as Mezzanine bus. Computer 200 typically includes a variety of computer readable media. Such media may be any available media that is locally and/or remotely accessible by computer 200, and it includes both volatile and non-volatile media, removable and non-removable media. In FIG. 2, the system memory 204 includes computer readable media in the form of volatile, such as random access memory (RAM) 210, and/or non-volatile memory, such as read only memory (ROM) 208. A basic input/output system (BIOS) 212, containing the basic routines that help to transfer information between elements within computer 200, such as during start-up, is stored in ROM 208. RAM 210 typically contains data and/or program modules that are immediately accessible to and/or presently be operated on by processing unit(s) 202. Computer 200 may further include other removable/non-removable, volatile/non-volatile computer storage media. By way of example only, FIG. 2 illustrates a hard disk drive 228 for reading from and writing to a non-removable, non-volatile magnetic media (not shown and typically called a “hard drive”), a magnetic disk drive 230 for reading from and writing to a removable, non-volatile magnetic disk 232 (e.g., a “floppy disk”), and an optical disk drive 234 for reading from or writing to a removable, non-volatile optical disk 236 such as a CD-ROM, DVD-ROM or other optical media. The hard disk drive 228, magnetic disk drive 230, and optical disk drive 234 are each connected to bus 206 by one or more interfaces 226. The drives and their associated computer-readable media provide nonvolatile storage of computer readable instructions, data structures, program modules, and other data for computer 200. Although the exemplary environment described herein employs a hard disk 228, a removable magnetic disk 232 and a removable optical disk 236, it should be appreciated by those skilled in the art that other types of computer readable media which can store data that is accessible by a computer, such as magnetic cassettes, flash memory cards, digital video disks, random access memories (RAMs), read only memories (ROM), and the like, may also be used in the exemplary operating environment. A number of program modules may be stored on the hard disk 228, magnetic disk 232, optical disk 236, ROM 208, or RAM 210, including, by way of example, and not limitation, an operating system 214, one or more application programs 216 (e.g., multimedia application program 224), other program modules 218, and program data 220. In accordance with the illustrated example embodiment of FIG. 2, operating system 214 includes an application program interface embodied as a render engine 222. As will be developed more fully below, render engine 222 is exposed to higher-level applications (e.g., 216) to automatically assemble filter graphs in support of user-defined development projects, e.g., media processing projects. Unlike conventional media processing systems, however, render engine 222 utilizes a scalable, dynamically reconfigurable matrix switch to reduce filter graph complexity, thereby reducing the computational and memory resources required to complete a development project. Various aspects of the innovative media processing system represented by a computer 200 implementing the innovative render engine 222 will be developed further, below. Continuing with FIG. 2, a user may enter commands and information into computer 200 through input devices such as keyboard 238 and pointing device 240 (such as a “mouse”). Other input devices may include a audio/video input device(s) 253, a microphone, joystick, game pad, satellite dish, serial port, scanner, or the like (not shown). These and other input devices are connected to the but may be connected by other interface and bus structures, such as a parallel port, game port, or a universal serial bus (USB). A monitor 256 or other type of display device is also connected to bus 206 via an interface, such as a video adapter 244. In addition to the monitor, personal computers typically include other peripheral output devices (not shown), such as speakers and printers, which may be connected through output peripheral interface 246. Computer 200 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 250. Remote computer 250 may include many or all of the elements and features described herein relative to computer 200 including, for example, render engine 222 and one or more development applications 216 utilizing the resources of render engine 222. As shown in FIG. 2. computing system 200 is communicatively coupled to remote devices (e.g., remote computer 250) through a local area network (LAN) 251 and a general wide area network (WAN) 252. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets, and the Internet. When used in a LAN networking environment, the computer 200 is connected to LAN 251 through a suitable network interface or adapter 248. When used in a WAN networking environment, the computer 200 typically includes a modem 254 or other means for establishing communications over the WAN 252. The modem 254, which may be internal or external, may be connected to the system bus 206 via the user input interface 242, or other appropriate mechanism. In a networked environment, program modules depicted relative to the personal computer 200, or portions thereof, may be stored in a remote memory storage device. By way of example, and not limitation, FIG. 2 illustrates remote application programs 216 as residing on a memory device of remote computer 250. It will be appreciated that the network connections shown and described are exemplary and other means of establishing a communications link between the computers may be used. Turning next to FIG. 3, a block diagram of an example development system architecture is presented, in accordance with one embodiment of the present invention. In accordance with the illustrated example embodiment of FIG. 3, development system 300 is shown comprising one or more application program(s) 216 coupled to render engine 222 via an appropriate communications interface 302. As used herein, application program(s) 216 are intended to represent any of a wide variety of applications which may benefit from use of render engine 222 such as, for example a media processing application 224. The communications interface 302 is intended to represent any of a number of alternate interfaces used by operating systems to expose application program interface(s) to applications. According to one example implementation, interface 302 is a component object model (COM) interface, as used by operating systems offered by Microsoft Corporation. As introduced above, COM interface 302 provides a means by which the features of the render engine 222, to be described more fully below, are exposed to an application program 216. In accordance with the illustrated example implementation of FIG. 3, render engine 222 is presented comprising source filter(s) 304A-N, transform filter(s) 306A-N and render filter 310, coupled together utilizing virtual pins to facilitate a user-defined media processing project. According to one implementation, the filters of system 300 are similar to the filters exposed in conventional media processing systems. According to one implementation, however, filters are not coupled via such interface pins. Rather, alternate implementations are envisioned wherein individual filters (implemented as objects) make calls to other objects, under the control of the render engine 222, for the desired input. Unlike conventional systems, however, render engine 222 exposes a scalable, dynamically reconfigurable matrix switch filter 308, automatically generated and dynamically configured by render engine 222 to reduce the computational and memory resource requirements often associated with development projects. As introduced above, the pins (input and/or output) are application interface(s) designed to communicatively couple other objects (e.g., filters). In accordance with the example implementation of a media processing system, an application communicates with an instance of render engine 222 when the application 216 wants to process streaming media content. Render engine 222 selectively invokes and controls an instance of filter graph manager (not shown) to automatically create a filter graph by invoking the appropriate filters (e.g., source, transform and rendering). As introduced above, the communication of media content between filters is achieved by either (1) coupling virtual output pins of one filter to the virtual input pins of requesting filter; or (2) by scheduling object calls between appropriate filters to communicate the requested information. As shown, source filter 304 receives streaming data from the invoking application or an external source (not shown). It is to be appreciated that the streaming data can be obtained from a file on a disk, a network, a satellite feed, an Internet server, a video cassette recorder, or other source of media content. As introduced above, transform filter(s) 306 take the media content and processes it in some manner, before passing it along to render filter 310. As used herein, transform filter(s) 306 are intended to represent a wide variety of processing methods or applications that can be performed on media content. In this regard, transform filter(s) 306 may well include a splitter, a decoder, a sizing filter, a transition filter, an effects filter, and the like. The function of each of these filters is described more fully in the Griffiths application, introduced above, and generally incorporated herein by reference. The transition filter, as used herein, is utilized by render engine 222 to transition the rendered output from a first source to a second source. The effect filter is selectively invoked to introduce a particular effect (e.g., fade, wipe, audio distortion, etc.) to a media stream. In accordance with one aspect of the embodiment, to be described more fully below, matrix switch filter 308 selectively passes media content from one or more of a scalable plurality of input(s) to a scalable plurality of output(s). Moreover, matrix switch 308 also supports implementation of a cascaded architecture utilizing feedback paths, i.e., wherein transform filters 306B, 306C, etc. coupled to the output of matrix switch 308 are dynamically coupled to one or more of the scalable plurality of matrix switch input(s). An example of this cascaded filter graph architecture is introduced in FIG. 3, and further explained in example implementations, below. Typically, media processed through source, transform and matrix switch filters are ultimately passed to render filter 310, which provides the necessary interface to a hardware device, or other location that accepts the renderer output format, such as a memory or disk file, or a rendering device. FIG. 4 is a graphical illustration of an example software-enabled matrix switch 308, according to one example embodiment of the present invention. As shown, the matrix switch 308 is comprised of a scalable plurality of input(s) 402 and a scalable plurality of output(s) 404, wherein any one or more of the input(s) 402 may be iteratively coupled to any one or more of the output(s) 404, based on the content of the matrix switch programming grid 406, automatically generated by render engine 222. According to an alternate implementation introduced above, switch matrix 308 is programmed by render engine 222 to dynamically generate object calls to communicate media content between filters. In addition, according to one implementation, matrix switch 308 includes a plurality of input/output (I/O) buffers 408, as well as means for maintaining source, or media time 410 and/or timeline, or project time 412. It is to be appreciated, however, that in alternate implementations matrix switch 308 does not maintain both source and project times, relying on an upstream filter to convert between these times. As will be developed more fully below, matrix switch 308 dynamically couples one or more of the scalable plurality of inputs 402 to one or more of the scalable plurality of outputs 404 based, at least in part, on the media time 410 and/or the project time 412 and the content of matrix switch programming grid 406. In this regard, matrix switch 308 may be characterized as time-aware, supporting such advanced editing features as searching/seeking to a particular point (e.g., media time) in the media content, facilitating an innovative buffering process utilizing I/O buffers 408 to facilitate look-ahead processing of media content, and the like. Thus, it will be appreciated given the discussion to follow that introduction of the matrix switch 308 provides a user with an editing flexibility that was heretofore unavailable in a personal computer-based media processing system. As introduced above, the inputs 402 and outputs 404 of matrix switch 308 are interfaces which facilitate the time-sensitive routing of data (e.g., media content) in accordance with a user-defined development project. Matrix switch 308 has a scalable plurality of inputs 402 and outputs 404, meaning that the number of inputs 402 and outputs 404 are individually generated to satisfy a given editing project. Insofar as each of the inputs/outputs (I/O) has an associated transfer buffer (preferably shared with an adjacent filter) to communicate media content, the scalability of the input/output serves to reduce the overall buffer memory consumed by an editing project. According to one implementation, output 1 is generally reserved as a primary output, e.g., coupled to a rendering filter (not shown). According to one implementation, for each input 402 and output 404, matrix switch 308 attempts to be the allocator, or manager of the buffer associated with the I/O(s) shared with adjacent filters. One reason is to ensure that all of the buffers are of the same size and share common attributes so that a buffer associated with any input 402 may be shared with any output 404, thereby reducing the need to copy memory contents between individual buffers associated with such inputs/outputs. If matrix switch 308 cannot be an allocator for a given output (404), communication from an input (402) to that output is performed using a conventional memory copy operation between the individual buffers associated with the select input/output. As introduced above, the matrix switch programming grid 406 is dynamically generated by render engine 222 based, at least in part, on the user-defined development project. As will be developed below, render engine 222 invokes an instance of filter graph manager to assembles a tree structure of an editing project, noting dependencies between source, filters and time to dynamically generate the programming grid 406. A data structure comprising an example programming grid 406 is introduced with reference to FIG. 5, below. Turning briefly to FIG. 5, a graphical representation of a data structure comprising an example programming grid 406 is presented, in accordance with one embodiment of the present invention. In accordance with the illustrated example embodiment of FIG. 5, programming grid 406 is depicted as a two-dimensional data structure comprising a column along the y-axis 502 of the grid denoting input pins associated with a content chain (e.g., series of filters to process media content) of the development project. The top row along the x-axis 504 of the data structure denotes project time. With these grid “borders”, the body 506 of the grid 406 is populated with output pin assignments, denoting which input pin is coupled to which output pin during execution of the development project. In this way, render engine 222 dynamically generates and facilitates matrix switch 308. Those skilled in the art will appreciate, however, that data structures of greater or lesser complexity may well be used in support of the programming grid 406 without deviating from the spirit and scope of the present invention. Returning to FIG. 4, matrix switch 308 is also depicted with a plurality of input/output buffers 408, shared among all of the input(s)/ouptut(s) (402, 404) to facilitate advanced processing features. That is, while not required to implement the core features of matrix switch 308, I/O buffers 408 facilitate a number of innovative performance enhancing features to improve the performance (or at least the user's perception of performance) of the processing system, thereby providing an improved user experience. According to one implementation, I/O buffers 408 are separate from the buffers assigned to each individual input and output pin in support of communication through the switch. According to one implementation, I/O buffers 408 are primarily used to foster look-ahead processing of the project. Assume, for example, that a large portion of the media processing project required only 50% of the available processing power, while some smaller portion required 150% of the available processing power. Implementation of the shared I/O buffers 408 enable filter graph manager to execute tasks ahead of schedule and buffer this content in the shared I/O buffers 408 until required. Thus, when execution of the filter graph reaches a point where more than 100% of the available processing power is required, the processing system can continue to supply content from the I/O buffers 408, while the system completes execution of the CPU-intensive tasks. If enough shared buffer space is provided, the user should never know that some tasks were not performed in real-time. According to one implementation, shared buffers 408 are dynamically split into two groups by render engine 222, a first group supports the input(s) 402, while a second (often smaller) group is used in support of a primary output (e.g., output pin 1) to facilitate a second, independent output processing thread. The use of an independent output buffers the render engine from processing delays that might occur in upstream and/or downstream filters, as discussed above. It will be appreciated by those skilled in the art that such that matrix switch 308 and the foregoing described architecture beneficially suited to support media streaming applications. As introduced above, the filter graph is time-aware in the sense that media (source) time and project execution time are maintained. According to one implementation, matrix switch 308 maintains at least the project clock, while an upstream filter maintains the source time, converting between source and project time for all downstream filters (i.e., including the matrix switch 308). According to one implementation, the frame rate converter filter of a filter graph is responsible for converting source time to project time, and vice versa, i.e., supporting random seeks, etc. Alternatively, matrix switch 308 utilizes an integrated set of clock(s) to independently maintain project and media times. Having introduced the architectural and operational elements of matrix switch filter 308, FIG. 6 graphically illustrates an example filter graph implementation incorporating the innovative matrix switch 308. In accordance with the illustrated example embodiment, filter graph 600 is generated by render engine 222 in response to a user defined development project. Unlike the lengthy linear filter graphs typical of convention development systems however, filter graph 600 is shown incorporating a matrix switch filter 308 to recursively route the pre-processed content (e.g., through filters 602, 606, 610, 614 and 618, described more fully below) through a user-defined number of transform filters including, for example, transition filter(s) 620 and effects filter(s) 622. Moreover, as will be developed more fully below, the scalable nature of matrix switch filter 308 facilitates such iterative processing for any number of content threads, tracks or compositions. According to one implementation, a matrix switch filter 308 can only process one type of media content, of the same size and at the same frame-rate (video) or modulation type/schema (audio). Thus, FIG. 6 is depicted comprising pre-processing filters with a parser filter 606 to separate, independent content type(s) (e.g., audio content and video content), wherein one of the media types would be processed along a different path including a separate instance of matrix switch 308. Thus, in accordance with the illustrated example embodiment of a media processing system, processing multimedia content including audio and video would utilize two (2) matrix switch filters 308, one dedicated to audio processing (not shown) and one dedicated to video processing. That is not to say, however, that multiple switch filters 308 could not be used (e.g., two each for audio and video) for each content type in alternate implementations. Similarly, it is anticipated that in alternate implementations a matrix switch 308 that accepts multiple media types could well be used without deviating from the spirit and scope of the present invention. In addition filter graph 600 includes a decoder filter 610 to decode the media content. Resize filter 614 is employed when matrix switch 308 is to receive content from multiple sources, ensuring that the size of the received content is the same, regardless of the source. According to one implementation, resize filter 614 selectively employed in video processing paths to adjust the media size of content from one or more sources to a user-defined level. Alternatively, resizer filter 614 adjusts the media size to the largest size provided by any one or more media sources. That is, if, for example, render engine 222 identifies the largest required media size (e.g., 1270×1040 video pixels per frame) and, for any content source not providing content at this size, the content is modified (e.g., stretched, packed, etc.) to fill this size requirement. The frame rate converter (FRC) and pack filter 618, introduced above, ensures that video content from the multiple sources is arriving at the same frame rate, e.g., ten (10) frames per second. As introduced above, the FRC also maintains the distinction between source time and project time. In accordance with one aspect of the present invention, filter graph 600 is depicted utilizing a single, negotiated buffer 604, 608, 612, 616, etc. between adjacent filters. In this regard, render engine 222 reduces the buffer memory requirements in support of a development project. From the point of pre-processing (filters 602, 606, 610, 614, 618), rather than continue a linear filter graph incorporating all of the transition 620 and effect 622 filter(s), render engine 222 utilizes a cascade architecture, recursively passing media content through the matrix switch 308 to apply to the transform filter(s) (e.g., 620, 622, etc.) to complete the execution of the development project. It will be appreciated by those skilled in the art that the ability to recursively pass media content through one or more effect and/or transition filters provided by the matrix switch filter 308 greatly reduces the perceived complexity of otherwise large filter graphs, while reducing memory and computational overhead. Turning to FIG. 7, a flow chart of an example method for generating a filter graph is presented, in accordance with one aspect of the present invention. The method 700 begins with block 702 wherein render engine 222 receives an indication to generate a filter graph representing a user-defined development project (e.g., a media editing project). According to one example implementation, the indication is received from an application 224 via COM interface(s) 302. In block 704, render engine 222 facilitates generation of the editing project, identifying the number and type of media sources selected by the user. In block 706, based at least in part on the number and/or type of media sources, filter graph manger 222 exposes source, transform and rendering filter(s) to effect a user defined media processing project, while beginning to establish a programming grid 406 for the matrix switch filter 308. In block 708, reflecting user editing instructions, render engine 222 completes the programming grid 406 for matrix switch 308, identifying which inputs 402 are to be coupled to which outputs 404 at particular project times. Based, at least in part, on the programming grid 406 render engine 222 generates a matrix switch filter 308 with an appropriate number of input 402 and output 404 pins to effect the project, and assembles the filter graph, block 710. In block 712, to reduce the buffer memory requirements for the processing project, the render engine 222 instructs the filters populating the filter graph to (re)negotiate buffer memory requirements between filters. That is, adjacent filters attempt to negotiate a size and attribute standard so that a single buffer can be utilized to couple each an output pin of one filter to an input pin of a downstream filter. An example implementation of the buffer negotiation process of block 712 is presented in greater detail with reference to FIG. 8. Turning briefly to FIG. 8, an example method of negotiating buffer requirements between adjacent filters is presented, in accordance with one example implementation of the present invention. Once the final connection is established to matrix switch 308, matrix switch 308 identifies the maximum buffer requirements for any filter coupled to any of its pins (input 402 and/or output 404), block 802. According to one implementation, the maximum buffer requirements are defined as the lowest common multiple of buffer alignment requirements, and the maximum of all the pre-fix requirements of the filter buffers. In block 804, matrix switch 308 selectively removes one or more existing filter connections to adjacent filters. Matrix switch 308 then reconnects all of its pins to adjacent filters using a common buffer size between each of the pins, block 806. In block 808, matrix switch 308 negotiates to be the allocator for all of its pins (402, 404). If the matrix switch 308 cannot, for whatever reason, be the allocator for any of its input pins 402 minimal loss to performance is encountered, as the buffer associated with the input pin will still be compatible with any downstream filter (i.e., coupled to an output pin) and, thus, the buffer can still be passed to the downstream filter without requiring a memory copy operation. If, however, matrix switch 308 cannot be an allocator for one of its output pins 404, media content must then be transferred to at least the downstream filter associated with that output pin using a memory copy operation, block 810. In block 812, once the matrix switch 308 has re-established its connection to adjacent filters, render engine 222 restores the connection in remaining filters using negotiated buffer requirements emanating from the matrix switch filter 308 buffer negotiations. Once the connections throughout the filter graph have been reconnected, the process continues with block 714 of FIG. 7. In block 714 (FIG. 7), have re-established the connections between filters, render engine 222 is ready to implement a user's instruction to execute the media processing project. Example Operation and Implementation(s) The matrix switch described above is quite useful in that it allows multiple inputs to be directed to multiple outputs at any one time. These input can compete for a matrix switch output. The embodiments described below permit these competing inputs to be organized so that the inputs smoothly flow through the matrix switch to provide a desired output. And, while the inventive programming techniques are described in connection with the matrix switch as such is employed in the context of multi-media editing projects, it should be clearly understood that application of the inventive programming techniques and structures should not be so limited only to application in the field of multi-media editing projects or, for that matter, multi-media applications or data streams. Accordingly, the principles about to be discussed can be applied to other fields of endeavor in which multiple inputs can be characterized as competing for a particular output during a common time period. In the multi-media example below, the primary output of the matrix switch is a data stream that defines an editing project that has been created by a user. Recall that this editing project can include multiple different sources that are combined in any number of different ways, and the sources that make up a project can comprise audio sources, video sources, or both. The organization of the inputs and outputs of the matrix switch are made manageable, in the examples described below, by a data structure that permits the matrix switch to be programmed. FIG. 9 shows an overview of a process that takes a user-defined editing project and renders from it a data structure that can be used to program the matrix switch. Specifically, a user-defined editing project is shown generally at 900. Typically, when a user creates an editing project, they can select from a number of different multimedia clips that they can then assemble into a unique presentation. Each individual clip represents a source of digital data or a source stream (e.g., multimedia content). Projects can include one or more sources 902. In defining their project, a user can operate on sources in different ways. For example, video sources can have transitions 904 and effects 906 applied on them. A transition object is a way to change between two or more sources. As discussed above, a transition essentially receives as input, two or more streams, operates on them in some way, and produces a single output stream. An exemplary transition can comprise, for example, fading from one source to another. An effect object can operate on a single source or on a composite of sources. An effect essentially receives a single input stream, operates on it in some way, and produces a single output stream. An exemplary effect can comprise a black-and-white effect in which a video stream that is configured for presentation in color format is rendered into a video stream that is configured for presentation in black and white format. Unlike conventional effect filters, effect object 906 may well perform multiple effect tasks. That is, in accordance with one implementation, an effect object (e.g., 906) may actually perform multiple tasks on the received input stream, wherein said tasks would require multiple effect filters in a conventional filter graph system. An exemplary user interface 908 is shown and represents what a user might see when they produce a multimedia project with software executing on a computer. In this example, the user has selected three sources A, B, and C, and has assembled the sources into a project timeline. The project timeline defines when the individual sources are to be rendered, as well as when any transitions and/or effects are to occur. In the discussion that follows, the notion of a track is introduced. A track can contain one or more sources or source clips. If a track contains more than one source clip, the source clips cannot overlap. If source clips are to overlap (e.g. fading from one source to another, or having one source obscure another), then multiple tracks are used. A track can thus logically represent a layer on which sequential video is produced. User interface 908 illustrates a project that utilizes three tracks, each of which contains a different source. In this particular project source A will show for a period of time. At a defined time in the presentation, source A is obscured by source B. At some later time, source B transitions to source C. In accordance with the described embodiment, the user-defined editing project 900 is translated into a data structure 910 that represents the project. In the illustrated and described example, this data structure 910 comprises a tree structure. It is to be understood, however, that other data structures could be used. The use of tree structures to represent editing projects is well-known and is not described here in any additional detail. Once the data structure 910 is defined, it is processed to provide a data structure 912 that is utilized to program the matrix switch. In the illustrated and described embodiment, data structure 912 comprises a grid from which the matrix switch can be programmed. It is to be understood and appreciated that other data structures and techniques could, however, be used to program the matrix switch without departing from the spirit and scope of the claimed subject matter. The processing that takes place to define data structures 910 and 912 can take place using any suitable hardware, software, firmware, or combination thereof. In the examples set forth below, the processing takes place utilizing software in the form of a video editing software package that is executable on a general purpose computer. Example Project For purposes of explanation, consider FIG. 10 which shows project 908 from FIG. 9 in a little additional detail. Here, a time line containing numbers 0-16 is provided adjacent the project to indicate when particular sources are to be seen and when transitions and effects (when present) are to occur. In the examples in this document, the following convention exists with respect to projects, such as project 908. A priority exists for video portions of the project such that as one proceeds from top to bottom, the priority increases. Thus, in the FIG. 10 example, source A has the lowest priority followed by source B and source C. Thus, if there is an overlap between higher and lower priority sources, the higher priority source will prevail. For example, source B will obscure source A from between t=4-8. In this example, the following can be ascertained from the project 908 and time line: from time t=0-4 source A should be routed to the matrix switch's primary output; from t=4-12 source B should be routed to the matrix switch's primary output; from t=12-14 there should be a transition between source B and source C which should be routed to the matrix switch's primary output; and from t=14-16 source C should be routed to the matrix switch's primary output. Thus, relative to the matrix switch, each of the sources and the transition can be characterized by where it is to be routed at any given time. Consider, for example, the table just below: Object Routing for a given time C t = 0-12 (nowhere); t = 12-14 (transition); t = 14-16 (primary output) B t = 0-4 (nowhere); t = 4-12 (primary output); t = 12-14 (transition); t = 14-16 (nowhere) A t = 0-4 (primary output); t = 4-16 (nowhere) Transition t = 0-12 (nowhere); t = 12-14 (primary output); t = 14-16 (nowhere) FIG. 11 shows an exemplary matrix switch 1100 that can be utilized in the presentation of the user's project. Matrix switch 1100 comprises multiple inputs and multiple outputs. Recall that a characteristic of the matrix switch 1100 is that any of the inputs can be routed to any of the outputs at any given time. A transition element 1102 is provided and represents the transition that is to occur between sources B and C. Notice that the matrix switch includes four inputs numbered 0-3 and three outputs numbered 0-2. Inputs 0-2 correspond respectively to sources A-C, while input 3 corresponds to the output of the transition element 1102. Output 0 corresponds to the switch's primary output, while outputs 1 and 2 are routed to the transition element 1102. The information that is contained in the table above is the information that is utilized to program the matrix switch. The discussion presented below describes but one implementation in which the information contained in the above table can be derived from the user's project time line. Recall that as a user edits or creates a project, software that comprises a part of their editing software builds a data structure that represents the project. In the FIG. 9 overview, this was data structure 910. In addition to building the data structure that represents the editing project, the software also builds and configures a matrix switch that is to be used to define the output stream that embodies the project. Building and configuring the matrix switch can include building the appropriate graphs (e.g., a collection of software objects, or filters) that are associated with each of the sources and associating those graphs with the correct inputs of the matrix switch. In addition, building and configuring the matrix switch can also include obtaining and incorporating additional appropriate filters with the matrix switch, e.g. filters for transitions, effects, and mixing (for audio streams). This will become more apparent below. FIG. 12 shows a graphic representation of an exemplary data structure 1200 that represents the project of FIG. 10. Here, the data structure comprises a traditional hierarchical tree structure. Any suitable data structure can, however, be utilized. The top node 1202 constitutes a group node. A group encapsulates a type of media. For example, in the present example the media type comprises video. Another media type is audio. The group node can have child nodes that are either tracks or composites. In the present example, three track nodes 1204, 1206, and 1208 are shown. Recall that each track can have one or more sources. If a track comprises more than one source, the sources cannot overlap. Here, all of the sources (A, B, and C) overlap. Hence, three different tracks are utilized for the sources. In terms of priority, the lowest priority source is placed into the tree furthest from the left at 1204a. The other sources are similarly placed. Notice that source C (1208a) has a transition 1210 associated with it. A transition object, in this example, defines a two-input/one output operation. When applied to a track or a composition (discussed below in more detail), the transition object will operate between the track to which it has been applied, and any objects that are beneath it in priority and at the same level in the tree. A “tree level” has a common depth within the tree and belongs to the same parent. Accordingly, in this example, the transition 1210 will operate on a source to the left of the track on which source C resides, and beneath it in priority, i.e. source B. If the transition is applied to any object that has nothing beneath it in the tree, it will transition from blackness (and/or silence if audio is included). Once a data structure representing the project has been built, in this case a hierarchical tree structure, a rendering engine processes the data structure to provide another data structure that is utilized to program the matrix switch. In the FIG. 9 example, this additional data structure is represented at 912. It will be appreciated and understood that the nodes of tree 1200 can include so-called meta information such as a name, ID, and a time value that represents when that particular node's object desires to be routed to the output, e.g. node 1204a would include an identifier for the node associating it with source A, as well as a time value that indicates that source A desires to be routed to the output from time t=0-8. This meta information is utilized to build the data structure that is, in turn, utilized to program the matrix switch. In the example about to be described below, a specific data structure in the form of a grid is utilized. In addition, certain specifics are described with respect to how the grid is processed so that the matrix switch can be programmed. It is to be understood that the specific described approach is for exemplary purposes only and is not intended to limit application of the claims. Rather, the specific approach constitutes but one way of implementing broader conceptual notions embodied by the inventive subject matter. FIGS. 13-18 represent a process through which the inventive grid is built. In the grid about to be described, the x axis represents time, and the y axis represents layers in terms of priority that go from lowest (at the top of the grid) to highest (at the bottom of the grid). Every row in the grid represents the video layer. Additionally, entries made within the grid represent output pins of the matrix switch. This will become apparent below. The way that the grid is built in this example is that the rendering engine does a traversal operation on the tree 1200. In this particular example, the traversal operation is known as a “depth-first, left-to-right” traversal. This operation will layerize the nodes so that the leftmost track or source has the lowest priority and so on. Doing the above-mentioned traversal on tree 1200 (FIG. 12), the first node encountered is node 1204 which is associated with source A. This is the lowest priority track or source. A first row is defined for the grid and is associated with source A. After the first grid row is defined, a grid entry is made and represents the time period for which source A desires to be routed to the matrix switch's primary output. FIG. 13 shows the state of a grid 1300 after this first processing step. Notice that from time t=0-8, a “0” has been placed in the grid. The “0” represents the output pin of the matrix switch-in this case the primary output. Next, the traversal encounters node 1206 (FIG. 12) which is associated with source B. A second row is thus defined for the grid and is associated with source B. After the second grid row is defined, a grid entry is made and represents the time period for which source B desires to be routed to the matrix switch's primary output. FIG. 14 shows the state of grid 1300 after this second processing step. Notice that from time t=4-14, a “0” has been placed in the grid. Notice at this point that something interesting has occurred which will be resolved below. Each of the layers has a common period of time (i.e. t=4-8) for which it desires to be routed to the matrix switch's primary output. However, because of the nature of the matrix switch, only one input can be routed to the primary output at a time. Next, the traversal encounters node 1208 (FIG. 12) which is associated with source C. In this particular processing example, a rule is defined that sources on tracks are processed before transitions on the tracks are processed because transitions operate on two objects that are beneath them. A third row is thus defined for the grid and is associated with source C. After the third row is defined, a grid entry is made and represents the time period for which source C desires to be routed to the matrix switch's primary output. FIG. 15 shows the state of grid 1300 after this third processing step. Notice that from time t=12-16, a “0” has been placed in the grid. Next, the traversal encounters node 1210 (FIG. 12) which corresponds to the transition. Thus, a fourth row is defined in the grid and is associated with the transition. After the fourth row is defined, a grid entry is made and represents the time period for which the transition desires to be routed to the matrix switch's primary output. FIG. 16 shows the state of grid 1300 after this fourth processing step. Notice that from time t=12-14, a “0” has been placed in the grid for the transition entry. The transition is a special grid entry. Recall that the transition is programmed to operate on two inputs and provide a single output. Accordingly, starting at the transition entry in the grid and working backward, each of the entries corresponding to the same tree level are examined to ascertain whether they contain entries that indicate that they want to be routed to the output during the same time that the transition is to be routed to the output. If grid entries are found that conflict with the transition's grid entry, the conflicting grid entry is changed to a value to corresponds to an output pin that serves as an input to the transition element 1102 (FIG. 11). This is essentially a redirection operation. In the illustrated grid example, the transition first finds the level that corresponds to source C. This level conflicts with the transition's grid entry for the time period t=12-14. Thus, for this time period, the grid entry for level C is changed to a switch output that corresponds to an input for the transition element. In this example, a “2” is placed in the grid to signify that for this given time period, this input is routed to output pin 2. Similarly, continuing up the grid, the next level that conflicts with the transition's grid entry is the level that corresponds to source B. Thus, for the conflicting time period, the grid entry for level B is changed to a switch output that corresponds to an input for the transition element. In this example, a “1” is placed in the grid to signify that for this given time period, this input is routed to output pin 1 of the matrix switch. FIG. 17 shows the state of the grid at this point in the processing. Next, a pruning function is implemented which removes any other lower priority entry that is contending for the output with a higher priority entry. In the example, the portion of A from t=4-8 gets removed because the higher priority B wants the output for that time. FIG. 18 shows the grid with a cross-hatched area that signifies that portion of A's grid entry that has been removed. At this point, the grid is in a state in which it can be used to program the matrix switch. The left side entries—A, B, C, and TRANS represent input pin numbers 0, 1, 2, and 3 (as shown) respectively, on the matrix switch shown in FIG. 11. The output pin numbers of the matrix switch are designated at 0, 1, and 2 both on the switch in FIG. 11 and within the grid in FIG. 18. As one proceeds through the grid, starting with source A, the programming of the matrix switch can be ascertained as follows: A is routed to output pin 0 of the matrix switch (the primary output) from t=0-4. From t=4-16, A is not routed to any output pins. From t=0-4, B is not routed to any of the output pins of the matrix switch. From t=4-12, B is routed to the primary output pin 0 of the matrix switch. From t=12-14, B is routed to output pin 1 of the matrix switch. Output pin 1 of the matrix switch corresponds to one of the input pins for the transition element 1102 (FIG. 11). From t=14-16, B is not routed to any of the output pins of the matrix switch. From t=0-12, C is not routed to any of the output pins of the matrix switch. From t=12-14, C is routed to output pin 2 of the matrix switch. Output pin 2 of the matrix switch corresponds to one of the input pins for the transition element 302 (FIG. 3). From t=12-14 the transition element (input pin 3) is routed to output pin 0. From t=14-16, C is routed to output pin 0 of the matrix switch. As alluded to above, one of the innovative aspects of the matrix switch 308 is its ability to seek to any point in a source, without having to process the intervening content serially through the filter. Rather, matrix switch 308 identifies an appropriate transition point and dumps at least a subset of the intervening content, and continues processing from the seeked point in the content. The ability of the matrix switch 308 to seek to any point in the media content gives rise to certain performance enhancement heretofore unavailable in computer implemented media processing systems. For example, generation of a filter graph by render engine 222 may take into account certain performance characteristics of the media processing system which will execute the user-defined media processing project. In accordance with this example implementation, render engine 222 may access and analyze the system registry of the operating system, for example, to ascertain the performance characteristics of hardware and/or software elements of the computing system implementing the media processing system, and adjust the filter graph construction to improve the perceived performance of the media processing system by the user. Nonetheless, there will always be a chance that a particular instance of a filter graph will not be able to process the media stream fast enough to provide the desired output at the desired time, i.e., processing of the media stream bogs down leading to delays at the rendering filter. In such a case, matrix switch 308 will recognize that it is not receiving media content at the appropriate project time, and may skip certain sections of the project in an effort to “catch-up” and continue the remainder of the project in real time. According to one implementation, when matrix switch 308 detects such a lag in processing, it will analyze the degree of the lag and issue a seek command to the source (through the source processing chain) to a future point in the project, where processing continues without processing any further content prior to the seeked point. Thus, for the editing project depicted in FIG. 10, the processing described above first builds a data structure (i.e. data structure 1200 in FIG. 12) that represents the project in hierarchical space, and then uses this data structure to define or create another data structure that can be utilized to program the matrix switch. FIG. 19 is a flow diagram that describes steps in a method in accordance with the described embodiment. The method can be implemented in any suitable hardware, software, firmware, or combination thereof. In the illustrated and described embodiment, the method is implemented in software. Step 1900 provides a matrix switch. An exemplary matrix switch is described above. Step 1902 defines a first data structure that represents the editing project. Any suitable data structure can be used, as will be apparent to those of skill in the art. In the illustrated and described embodiment, the data structure comprises a hierarchical tree structure having nodes that can represent tracks (having one or more sources), composites, transitions and effects. Step 1904 processes the first data structure to provide a second data structure that is configured to program the matrix switch. Any suitable data structure can be utilized to implement the second data structure. In the illustrated and described embodiment, a grid structure is utilized. Exemplary processing techniques for processing the first data structure to provide the second data structure are described above. Step 1906 then uses the second data structure to program the matrix switch. Example Project with a Transition and an Effect Consider project 2000 depicted in FIG. 20. In this project there are three tracks, each of which contains a source, i.e. source A, B and C. This project includes an effect applied on source B and a transition between sources B and C. The times are indicated as shown. As the user creates their project, a data structure representing the project is built. FIG. 21 shows an exemplary data structure in the form of a hierarchical tree 2100 that represents project 2000. There, the data structure includes three tracks, each of which contains one of the sources. The sources are arranged in the tree structure in the order of their priority, starting with the lowest priority source on the left and proceeding to the right. There is an effect (i.e. “Fx”) that is attached to or otherwise associated with source B. Additionally, there is a transition attached to or otherwise associated with source C. In building the grid for project 2000, the following rule is employed for effects. An effect, in this example, is a one-input/one-output object that is applied to one object—in this case source B. When the effect is inserted into the grid, it looks for any one object beneath it in priority that has a desire to be routed to the primary output of the matrix switch at the same time. When it finds a suitable object, it redirects that object's output from the matrix switch's primary output to an output associated with the effect. As an example, consider FIG. 22 and the grid 2200. At this point in the processing of tree 2100, the rendering engine has incorporated entries in the grid corresponding to sources A, B and the effect. It has done so by traversing the tree 2100 in the above-described way. In this example, the effect has already looked for an object beneath it in priority that is competing for the primary output of the matrix switch. It found an entry for source B and then redirected B's grid entry to a matrix switch output pin that corresponds to the effect—here output pin 1. As the render engine 222 completes its traversal of tree 2100, it completes the grid. FIG. 23 shows a completed grid 2200. Processing of the grid after that which is indicated in FIG. 22 takes place substantially as described above with respect to the first example. Summarizing, this processing though: after the effect is entered into the grid and processed as described above, the traversal of tree 2100 next encounters the node associated with source C. Thus, a row is added in the grid for source C and an entry is made to indicate that source C desires the output from t=12-16. Next, the tree traversal encounters the node associated with the transition. Accordingly, a row is added to the grid for the transition and a grid entry is made to indicate that the transition desires the output from t=12-14. Now, as described above, the grid is examined to find two entries, lower in priority than the transition and located at the same tree level as the transition, that compete for the primary output of the matrix switch. Here, those entries correspond to the grid entries for the effect and source C that occur from t=12-14. These grid entries are thus redirected to output pins of the matrix switch 308 that correspond to the transition—here pins 2 and 3 as indicated. Next, the grid is pruned which, in this example, removes a portion of the grid entry corresponding to source A for t=4-8 because of a conflict with the higher-priority entry for source B. FIG. 24 shows the resultant matrix switch that has been built and configured as the grid was being processed above. At this point, the grid can be used to program the matrix switch. From the grid picture, it is very easy to see how the matrix switch 308 is going to be programmed. Source A will be routed to the matrix switch's primary output (pin 0) from t=0-4; source B will be redirected to 11 output pin 1 (effect) from t=4-14 and the effect on B will be routed to the output pin 0 from t=4-12. From t=12-14, the effect and source C will be routed to output pins corresponding to the transition (pins 2 and 3) and, accordingly, during this time the transition (input pin 4) will be routed to the primary output (output pin 0) of the matrix switch. From t=14-16, source C will be routed to the primary output of the matrix switch. It will be appreciated that as the software, in this case the render engine 222, traverses the tree structure that represents a project, it also builds the appropriate graphs and adds the appropriate filters and graphs to the matrix switch. Thus, for example, as the render engine 222 encounters a tree node associated with source A, in addition to adding an entry to the appropriate grid, the software builds the appropriate graphs (i.e. collection of linked filters), and associates those filters with an input of the matrix switch. Similarly, when the render engine 222 encounters an effect node in the tree, the software obtains an effect object or filter and associates it with the appropriate output of the matrix switch. Thus, in the above examples, traversal of the tree structure representing the project also enables the software to construct the appropriate graphs and obtain the appropriate objects and associate those items with the appropriate inputs/outputs of the matrix switch 308. Upon completion of the tree traversal and processing of the grid, an appropriate matrix switch has been constructed, and the programming (i.e. timing) of inputs to outputs for the matrix switch has been completed. Treatment of “blanks” in a Project There may be instances in a project when a user leaves a blank in the project time line. During this blank period, no video or audio is scheduled for play. FIG. 25 shows a project that has such a blank incorporated therein. If there is such a blank left in a project, the software is configured to obtain a “black” source and associate the source with the matrix switch at the appropriate input pin. The grid is then configured when it is built to route the black source to the output at the appropriate times and fade from the black (and silent) source to the next source at the appropriate times. The black source can also be used if there is a transition placed on a source for which there is no additional source from which to transition. Audio Mixing In the examples discussed above, sources comprising video streams were discussed. In those examples, at any one time, only two video streams were combined into one video stream. However, each project can, and usually does contain an audio component. Alternately, a project can contain only an audio component. The audio component can typically comprise a number of different audio streams that are combined. The discussion below sets forth but one way of processing and combining audio streams. In the illustrated example, there is no limit on the number of audio streams that can be combined at any one time. Suppose, for example, there is an audio project that comprises 5 tracks, A-E. FIG. 26 shows an exemplary project. The shaded portions of each track represent the time during which the track is not playing. So, for example, at t=0-4, tracks B, D, and E are mixed together and will play. From t=4-10, tracks A-E are mixed together and will play, and the like. FIG. 27 shows the grid for this project at 2700. Since we are dealing with this composition now, all of the effects and transitions including the audio mixing are only allowed to affect things in this composition. Thus, there is the concept of a boundary 2702 that prevents any actions or operations in this composition from affecting any other grid entries. Note that there are other entries in the grid and that the presently-illustrated entries represent only those portions of the project that relate to the audio mixing function. Grid 2700 is essentially set up in a manner similar to that described above with respect to the video projects. That is, for each track, a row is added to the grid and a grid entry is made for the time period during which the source on that track desires to be routed to the primary output of the matrix switch. In the present example, grid entries are made for sources A-E. Next, in the same way that a transition or effect was allocated a row in the grid, a “mix” element is allocated a row in the grid as shown and a grid entry is made to indicate that the mix element desires to be routed to the primary output of the matrix switch for a period of time during which two or more sources compete for the matrix switch's primary output. Note that in this embodiment, allocation of a grid row for the mix element can be implied. Specifically, whereas in the case of a video project, overlapping sources simply result in playing the higher priority source (unless the user defines a transition between them), in the audio realm, overlapping sources are treated as an implicit request to mix them. Thus, the mix element is allocated a grid row any time there are two or more overlapping sources. Once the mix element is allocated into the grid, the grid is processed to redirect any conflicting source entries to matrix switch output pins that correspond to the mix element. In the above case, redirection of the grid entries starts with pin 3 and proceeds through to pin 7. The corresponding matrix switch is shown in FIG. 28. Notice that all of the sources are now redirected through the mix element which is a multi-input/one output element. The mix element's output is fed back around and becomes input pin 15 of the matrix switch. All of the programming of the matrix switch is now reflected in the grid 2700. Specifically, for the indicated time period in the grid, each of the sources is routed to the mix element which, in turn, mixes the appropriate audio streams and presents them to the primary output pin 0 of the matrix switch. Compositions There are situations that can arise when building an editing project where it would be desirable to apply an effect or a transition on just a subset of a particular project or track. Yet, there is no practicable way to incorporate the desired effect or transition. In the past, attempts to provide added flexibility for editing projects have been made in the form of so called “bounce tracks”, as will be appreciated and understood by those of skill in the art. The use of bounce tracks essentially involves processing various video layers (i.e. tracks), writing or moving the processed layers or tracks to another location, and retrieving the processed layers when later needed for additional processing with other layers or tracks. This type of processing can be slow and inefficient. To provide added flexibility and efficiency for multi-media editing projects, the notion of a composite or composition is introduced. A composite or composition can be considered as a representation of an editing project as a single track. Recall that editing projects can have one or more tracks, and each track can be associated with one or more sources that can have effects applied on them or transitions between them. In addition, compositions can be nested inside one another. Example Project with Composite Consider, for example, FIG. 29 which illustrates an exemplary project 2900 having a composition 2902. In this example, composition 2902 comprises sources B and C and a transition between B and C that occurs between t=12-14. This composition is treated as an individual track or layer. Project 2900 also includes a source A, and a transition between source A and composition 2902 at t=4-8. It will be appreciated that compositions can be much more complicated than the illustrated composition, which is provided for exemplary purposes only. Compositions are useful because they allow the grouping of a particular set of operations on one or more tracks. The operation set is performed on the grouping, and does not affect tracks that are not within the grouping. To draw an analogy, a composition is similar in principle to a mathematical parenthesis. Those operations that appear within the parenthesis are carried out in conjunction with those operations that are intended to operate of the subject matter of the parenthesis. The operations within the parenthesis do not affect tracks that do not appear within the parenthesis. In accordance with the processing that is described above in connection with FIG. 19, a first data structure is defined that represents the editing project. FIG. 30 shows an exemplary data structure 3000 in the form of a hierarchical tree structure. In this example, group node 3002 includes two children—track node 3004 and composite node 3006. Track node 3004 is associated with source A. Composite node 3006 includes two children—track nodes 3008 and 3010 that are respectively associated with sources B (3008a) and C (3010a). A transition T2 (3012) is applied on source C and a transition T1 (3014) is applied on composition 3006. Next, data structure 3000 is processed to provide a second data structure that is configured to program the matrix switch. Note that as the data structure is being programmed, a matrix switch is being built and configured at the same time. In this example, the second data structure comprises a grid structure that is assembled in much the same way as was described above. There are, however, some differences and, for purposes of understanding, the complete evolution of the structure is described here. In the discussion that follows, the completed matrix switch is shown in FIG. 38. When the rendering engine initiates the depth-first, left-to-right traversal of data structure 3000, the first node it encounters is track node 3004 which is associated with source A. Thus, a first row of the grid is defined and a grid entry is made that represents the time period for which source A desires to be routed to the matrix switch's primary output pin. FIG. 31 shows the state of a grid 3100 after this first processing step. Next the traversal of data structure 3000 encounters the composite node 3006. The composite node is associated with two tracks—track 3008 and track 3010. Track 3008 is associated with source B. Accordingly, a second tow of the grid is defined and a grid entry is made that represents the time period for which source B desires to be routed to the matrix switch's primary output pin. Additionally, since B is a member of a composition, meta-information is contained in the grid that indicates that this grid row defines one boundary of the composition. This meta-11 information is graphically depicted with a bracket that appears to the left of the grid row. FIG. 32 shows the state of grid 3100 after this processing step. Next, the traversal of data structure 3000 encounters node 3010 which is associated with source C. Thus, a third row of the grid is added and a grid entry is made that represents the time period for which source C desires to be routed to the matrix switch's primary output pin. FIG. 33 shows the state of grid 3100 after this processing step. Notice that the bracket designating the composition now encompasses the grid row associated with source C. The traversal next encounters node 3012 which is the node associated with the second transition T2. Thus, as in the above example, a grid row is added for the transition and a grid entry is made that represents the time period for which the transition desires to be routed to the matrix switch's primary output pin. FIG. 34 shows the state of grid 3100 after this processing step. Notice that the bracket designating the composition is now completed and encompasses grid row entries that correspond to sources B and C and the transition between them. Recall from the examples above that a transition, in this example, is programmed to operate on two inputs and provide a single output. In this instance, and because the transition occurs within a composition, the transition is constrained by a rule that does not allow it to operate on any elements outside of the composition. Thus, starting at the transition entry and working backward through the grid, entries at the same tree level and within the composition (as designated by the bracket) are examined to ascertain whether they contain entries that indicate that they want to be routed to the output during the same time that the transition is to be routed to the output. Here, both of the entries for sources B and C have portions that conflict with the transition's entry. Accordingly, those portions of the grid entries for sources B and C are redirected or changed to correspond to output pins that are associated with a transition element that corresponds to transition T2. FIG. 35 shows the state of grid 3100 after this processing step. The traversal next encounters node 3014 which is the node that is associated with the transition that occurs between source A and composition 2902 (FIG. 29). Processing of this transition is similar to processing of the transition immediately above except for the fact that the transition does not occur within the composition. Because the transition occurs between the composition and another source, one of the inputs for the transition will be the composition, and one of the inputs will be source A (which is outside of the composition). Thus, a grid row is added for this transition and a grid entry is made that represents the time period for which the transition desires to be routed to the matrix switch's primary output pin. FIG. 36 shows the state of grid 3100 after this processing step. At this point then, the grid is examined for entries that conflict with the entry for transition T1. One conflicting grid entry is found for the row that corresponds to source B (inside the composition) and one that corresponds to source A (outside the composition). Accordingly, those portions of the grid row that conflict with transition T1 are changed or redirected to have values that are associated with output pins of the matrix switch that are themselves associated with a transition element T1. In this example, redirection causes an entry of “3” and “4” to be inserted as shown. FIG. 37 shows the state of grid 3100 after this processing step. If necessary, a pruning operation would further ensure that the grid has no competing entries for the primary output of the matrix switch. The associated input pin numbers of the matrix switch are shown to the left of grid 3100. FIG. 38 shows a suitably configured matrix switch that has been build in accordance with the processing described above. Recall that, as data structure 3000 (FIG. 30) is processed by the rendering engine, a matrix switch is built and configured in parallel with the building and processing of the grid structure that is utilized to program the matrix switch. From the matrix switch and grid 3100 of FIG. 37, the programming of the switch can be easily ascertained. FIG. 38a shows an exemplary data structure that represents a project that illustrates the usefulness of composites. In this example, the project can mathematically be represented as follows: (Fx-noisy (A Tx-Blend B)) Tx-Blend C Here, an effect (noisy) is applied to A blended with B, the result of which is applied to a blend with C. The composite in this example allows the grouping of the things beneath it so that the effect (noisy), when it is applied, is applied to everything that is beneath it. Notice that without the composite node, there is no node where an effect can be applied that will affect (A Tx-Blend B). Hence, in this example, operations that appear within the parenthesis are carried out on tracks that appear within the parenthesis. Those operations do not affect tracks that are not within the parenthesis. FIG. 39 is a flow diagram that described steps in a method in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware, or combination thereof. In the presently-described example, the method is implemented in software. Step 3900 defines a multimedia editing project that includes at least one composite. The composite represents multiple tracks as a single track for purposes of the processing described just below. It is important to note that, in the processing described just below, and because of the use of composites, the extra processing that is required by bounce tracks is avoided (i.e. operating on two tracks, moving the operation result to another location, and retrieving the operation result when later needed). This reduces the processing time that is required to render a multi-media project. Step 3902 defines a first data structure that represents the editing project. Any suitable data structure can be utilized. In the present example, a data structure in the form of a hierarchical tree is utilized. An exemplary tree is shown in FIG. 30. Step 3904 processes the first data structure to provide a second data structure that is configured to program a matrix switch. In the illustrated example, the second data structure comprises a grid structure. Exemplary processing is described in the context of FIGS. 30-37. Step 3906 then programs the matrix switch using the second data structure. Although the invention has been described in language specific to structural features and/or methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or steps described. Rather, the specific features and steps are disclosed as preferred forms of implementing the claimed invention. | <SOH> BACKGROUND <EOH>Recent advances in computing power and related technology have fostered the development of a new generation of powerful software applications. Gaming applications, communications applications, and multimedia applications have particularly benefited from increased processing power and clocking speeds. Indeed, once the province of dedicated, specialty workstations, many personal computing systems now have the capacity to receive, process and render multimedia objects (e.g., audio and video content). While the ability to display (receive, process and render) multimedia content has been around for a while, the ability for a standard computing system to support true multimedia editing applications is relatively new. In an effort to satisfy this need, Microsoft Corporation introduced a multimedia processing architecture that supports editing functions. An example of this architecture is presented in a U.S. Pat. No. 5,913,038 issued to Griffiths and commonly owned by the assignee of the present invention, the disclosure of which is expressly incorporated herein by reference. In the '038 patent, Griffiths introduced the filter graph manager, exposed to higher-level, user interface application(s), which enabled a user to graphically construct a multimedia processing project by piecing together a collection of filters offered by the filter graph manager. The filter graph manager controls the data structure of the filter graph and the way data moves through the filter graph. The filter graph manager provides a set of component object model (COM) interfaces for communication between a filter graph and its application. Filters of a filter graph architecture are preferably implemented as COM objects, each implementing one or more interfaces, each of which contains a predefined set of functions, called methods. Methods are called by an application program or other component objects in order to communicate with the object exposing the interface. The application program can also call methods or interfaces exposed by the filter graph manager object. Filter graphs work with data representing a variety of media (or non-media) data types, each type characterized by a data stream that is processed by the filter components comprising the filter graph. A filter positioned closer to the source of the data is referred to as an upstream filter, while those further down the processing chain is referred to as a downstream filter. For each data stream that the filter handles it exposes at least one virtual pin (i.e., distinguished from a physical pin such as one might find on an integrated circuit). A virtual pin can be implemented as a COM object that represents a point of connection for a unidirectional data stream on a filter. Input pins represent inputs and accept data into the filter, while output pins represent outputs and provide data to other filters. Each of the filters include at least one memory buffer, wherein communication of the media stream between filters is accomplished by a series of “copy” operations from one filter to another. As introduced in Griffiths, a filter graph has three different types of filters: source filters, transform filters, and rendering filters. A source filter is used to load data from some source; a transform filter processes and passes data; and a rendering filter renders data to a hardware device or other locations (e.g., saved to a file, etc.). An example of a filter graph for a simplistic media rendering process is presented with reference to FIG. 1 . FIG. 1 graphically illustrates an example filter graph for rendering media content. As shown, the filter graph 10 is comprised of a plurality of filters 124 - 22 , which read, process (transform) and render media content from a selected source file. As shown, the filter graph includes each of the types of filters described above, interconnected in a linear fashion. Products utilizing the filter graph have been well received in the market as it has opened the door to multimedia editing using otherwise standard computing systems. It is to be appreciated, however, that the construction and implementation of the filter graphs are computationally intensive and expensive in terms of memory usage. Even the most simple of filter graphs requires and abundance of memory to facilitate the copy operations required to move data between filters. Complex filter graphs can become unwieldy, due in part to the linear nature of prior art filter graph architecture. Moreover, it is to be appreciated that the filter graphs themselves consume memory resources, thereby compounding the issue introduced above. Thus, what is required is a filter graph architecture which reduces the computational and memory resources required to support even the most complex of multimedia projects. Indeed, what is required is a dynamically reconfigurable multimedia editing system and related methods, unencumbered by the limitations described above. Just such a system and methods are disclosed below. | <SOH> SUMMARY <EOH>In one embodiment, a system receives an indication to generate a filter graph representing a user-defined development project. Media sources that are to be used in the user-defined development project are identified and a programming grid is establishing that incorporates a user's editing instructions. A matrix switch filter is generated based, at least in part, on the programming grid. The filter graph is assembled and comprises a plurality of individual filters. Buffer size and attribute characteristics are negotiated between an input/output of the matrix switch filter and an input/output of adjacent filters. Negotiated buffers are utilized to communicate media content between the matrix switch filter and adjacent filters by sharing a common buffer between inputs and outputs. | 20050119 | 20060718 | 20050707 | 66795.0 | 0 | NGUYEN, VAN H | SYSTEMS FOR NEGOTIATING BUFFER SIZE AND ATTRIBUTE CHARACTERISTICS IN MEDIA PROCESSING SYSTEMS THAT CREATE USER-DEFINED DEVELOPMENT PROJECTS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,708 | ACCEPTED | Flexible cable interconnect with integrated EMC shielding | In a flat flex cable, signal lines are surrounded by logic ground planes above and below which are viaed together left and right. The ground planes coupled with the flex cable dielectric determine characteristic the impedance and attenuation of the cable and provide differential signal EMI shielding. All signal layers and logic ground planes are enclosed within the two outermost shield layers which are viaed together left and right and around the connectors to enclose both signal layers and logic ground planes to provide common mode EMI shielding. | 1. A shielded flat flexible cable comprising at least one series of conductor traces secured to the surface of a dielectric support layer; first and second conductive logic ground layers disposed respectively above and below said at least one series of conductor traces and separated therefrom by a layer of dielectric material; third and fourth conductive frame ground layers respectively disposed above said first conductive logic ground layer and below said second conductive logic ground layer and separated therefrom by a layer of dielectric material; said third and fourth conductive frame ground layers extending laterally beyond said first and second logic ground layers; and periodic electrical connecting means electrically connecting said third and fourth conductive frame ground layers along the marginal edge portions of said frame ground layers which extend laterally beyond said first and second conductive logic ground layers. 2. The shielded flat flexible cable of claim 1 wherein said periodic electrical connecting means comprises a first sequence of plated through vias which electrically connect said third and fourth conductive frame ground layers at locations beyond the lateral edges of said first and second conductive logic ground layers. 3. The shielded flat flexible cable of claim 2 wherein adjoining plated through vias of said electrical connecting means are separated by a distance which is smaller than the wave length of the highest frequency signal carried by said conductor traces. 4. The shielded flat flexible cable of claim 3 wherein said third and fourth conductive frame ground layers comprise a common mode EMI shield which is electrically connected to a device frame adjacent each cable end. 5. The shielded flat flexible cable of claim 2 wherein said cable comprises a plurality of layers of conductive traces with a logic ground layer, similar to said first and second conductive logic ground layers, positioned between and electrically isolated from each of the adjoining layers of conductor traces. 6. The shielded flat flexible cable of claim 5 further comprising a second sequence of plated through vias electrically interconnecting said conductive logic ground layers laterally outward with respect to signal carrying traces of each said layer of conductive traces, said second sequence of plated through vias being laterally inward and longitudinally staggered with respect to said first sequence of plated through vias. 7. A shielded flat flexible cable comprising: at least one series of conductive traces secured to the surface of a dielectric support layer; first and second conductive logic ground layers respectively disposed above said first conductive logic ground layer and below said second conductive logic ground layer and separated therefrom by a layer of dielectric material; third and fourth conductive frame ground layers respectively disposed above said first conductive logic ground layer and below said second conductive logic ground layer and separated therefrom by a layer of dielectric material; and a series of periodic electrical connecting means electrically connecting said third and fourth conductive frame ground layers along marginal edge portions of said frame ground layers causing the frame ground to surround and be electrically isolated from said conductive traces and said first and second logic ground layers. 8. The shielded flat flexible cable of claim 7 wherein said periodic electrical connecting means comprises a first sequence of plated through vias which electrically connect said third and fourth conductive frame ground layers. 9. The shielded flat flexible cable of claim 8 where adjoining plated through vias of said electrical connecting means are separated by a distance which is smaller than the wave length of the highest frequency signal carried by said conductive traces. 10. (canceled) 11. The shielded flat flexible cable of claim 8 wherein said cable comprises a plurality of layers of conductive traces with an intervening logic ground layer positioned between and electrically isolated from each of the adjoining layers of conductive traces. 12. The shielded flat flexible cable of claim 11 further comprising a second sequence of plated through vias electrically connecting said first and second logic ground layers and said intervening logic ground layers laterally outward with respect to signal carrying traces of said layers of conductive traces. 13. The shielded flat flexible cable of claim 12 wherein said second sequence of plated through vias are positioned laterally inward and electrically isolated from said first sequence of plated through vias and longitudinally staggered with respect to said first sequence of plated through vias. | FELD OF THE INVENTION The invention pertains to flat flex cables and more particularly to EMC (electromagnetic compatibility) shielded and grounded flex cables for use externally between devices. BACKGROUND OF THE INVENTION Electronic systems composed of multiple devices housed in separate enclosures commonly require external signal interconnects between devices. These systems require that integrated EMC shielding be provided in the flexible cabling extending between enclosures. It is not unusual to find that the external connecting cables are among the largest structures in the system, with the result that common mode currents on these cables are almost always the source of an EMI (electromagnetic interference) problem. To control both differential mode and common mode signals it is necessary to provide both logic ground shielding about the signal lines and secondary frame ground shielding about the logic ground shielding. High performance double shielded coaxial cables are a solution, but are too bulky and require large radius bends and as a result are not suitable for use in current state of the art devices that are continuously attempting to achieve smaller, more compact device sizes. SUMMARY OF THE INVENTION This invention provides integrated EMC shielding and grounding for flex cables allowing them to be used externally of device enclosures to afford interconnection. The high density flexible interconnecting cable includes a combination of high performance signals enclosed within and referencing surrounding logic ground planes, surrounded by frame ground shield layers which are viaed together at the external boundaries of the cable throughout the cable's entire length, thus forming an external cable shield. These outer frame ground layers are then physically connected to the frame or chassis ground of the connected device at both the source and termination locations of the cable. This combination of surrounding the signals with both logic ground and then frame ground controls both the differential mode and common mode EMI, necessary for high performance EMI shielding, as well as providing the controlled impedance necessary for signal integrity in a high speed interconnect environment. The advantages of this flat flex cable design is high performance EMI shielding of a high density pin count interconnect that can be used where a small bend radius is required while still retaining enough flexibility for concurrent maintenance. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a flex cable incorporating the present invention with one plate member surrounding a connector site removed to illustrate the frame ground via sequence. FIG. 2 is a schematic view of the cable structure taken along line 2-2 of FIG. 1. FIG. 3 is an exploded schematic view of the dielectric layers of FIG. 2 including the copper and adhesive layers prior to assembly. DETAILED DESCRIPTION FIG. 1 illustrates an example of the shielded flat flexible cable 10 of the present invention as an external cable assembly for interconnecting signal lines of two devices that connect to the cable at the high density pin connector sites 12 and 13. The layered structure of the cable is shown in FIG. 2 taken along line 2-2 of FIG. 1, with an exploded view of FIG. 2 shown in FIG. 3 wherein the individual layers of dielectric material and the coatings of etched copper and adhesive are identified. As seen in the exploded view of FIG. 3, the flexible cable 10 is formed of a series of dielectric layers which separate the various etched copper layers. A typical dielectric used for these layers is polyimide film. The dielectric layers 14 and 15 each have an upper copper coating which is etched to form a series of conductive traces 17 and carries on the lower surface a copper coating 18 which extends laterally beyond the conductive traces 18, but is etched away from the outer edge of cable 10 to form a logic ground plane. The conductive traces 17 are principally signal lines, but may also include logic ground lines which cooperate the logic ground planes and dielectric material characteristics to optimize signal line performance or reduce signal line emissions. As shown, cable 10 contains two layers of conductive traces 17, but the cable could be designed with a single layer or three or more layers of conductive traces to meet the requirements of the devices that are to be interconnected. The polyimide dielectric layer 21 carries adhesive coatings 22 on each side and functions to separate the ground plane 18 from the conductive traces 17. Dielectric layers 24 and 25 (similarly coated on each side with adhesive coatings 26) provide electrical isolation of the conductive trace layers from the adjacent conductive layers. Dielectric layer 29 has a logic ground plane copper surface 30 at the lower surface which, like logic ground planes 18, extends over conductive traces 17, but is etched away at the cable edge. Thus, copper layers 18 and 30 function to provide a logic ground plane immediately above and below each layer of conductive traces 17. The upper surfaces of dielectric layers 29 and 33 are respectively coated with copper layers 34 and 35, which are the principal conductive surfaces forming the frame ground to provide the common mode EMI shielding. Each of the copper layers 34 and 35 extend to the edge or near to the edge of the polyimide dielectric layer upon which they are formed and thereby to the edge or near to the edge of the cable assembly 10. The copper layers 34 and 35 are etched to form generally circular voids 37 which are aligned with the margins of the logic ground planes 18 and 30 to enable vias to be formed subsequently that connect the logic ground planes, but are electrically isolated from the frame ground planes 34 and 35. A final pad cap layer 40 is provided at the upper surface of the cable assembly 10 as a copper layer on polyimide dielectric layer 41. Dielectric layer 41 has an adhesive layer 42 on the lower surface to enable attachment to the frame ground layer 37. A similar copper pad cap layer 45 is presented at the lower surface of the dielectric layer 33. The pad cap layers 40 and 45 are subsequently etched to remove the copper from all, but the pad caps which are utilized to enable via interconnects for the ground planes as described below and for signal line interconnecting vias which are not further described herein. FIG. 2 is a section of the cable edge showing the assembled condition of the cable 10. FIGS. 2 and 3 are schematic views for purposes of illustration, wherein the layer thicknesses are not to scale. In FIG. 2 the thickness of the assembly adjacent the outer edge would actually be modestly reduced as a consequence of the copper layers that do not extend to the cable edge. With the dielectric layers compressed together and bonded by the adhesive coatings, two series of holes 48 and 49 are drilled through the assembly to enable plated through vias to be formed. Along the entire perimeter of the cable a series of vias 54 are formed, each extending through a drilled hole 48 between a pad 51 at the upper surface 52 and a pad 53 at the lower surface 56. The outermost row of vias 54 each electrically connects the upper ground frame layer 34 to the lower ground frame layer 35 and together form a sequence of electrical connections. An inner row of vias 55, each extending from an upper pad cap 57 to a lower pad cap 58 and through openings 37 in the frame ground layers 34 and 35, interconnect the logic ground plane layers 18 and 30 disposed above and below each of the conductive trace layers 17. The inner row of vias 55 form a sequence of periodic electrical connecting means which extends along the length of the cable assembly, but are not present in the interconnect areas about the high density interconnect sites 12 and 13 of the cable assembly. The spacing between the outer row of frame ground vias 54 is selected such that the space between adjoining vias is smaller than the wave length of the highest frequency signal encountered on the signal lines. The sequence of inner row logic ground vias are longitudinally staggered with respect to the outer row vias 54 so that the vias of one sequence are aligned with the spaces separating vias of the other sequence. The staggered via rows thereby maximize the optical coverage as viewed from the cable edge to maximize the shielding effectiveness of the overall shielding system. As seen in FIG. 1, the series of pad caps 51 and the sequence of vias connecting the marginal edge portions of the frame ground planes to which they are connected extend about the entire periphery of the cable 10 including the terminal end portions 60 and 61. The terminal end portions include a metal plate member 63 which overlies the cable and surrounds the connector site such as site 13 of terminal end 61. Terminal end 60 is shown with the plate removed to reveal the continuous row of via pad caps 51 about the edge of the cable assembly. The plate 63, as shown installed on terminal end 61, is bonded to the cable and electrically connected to the underlying pad caps 51 to afford a positive frame ground connection as the plate 63 engages the frame of the device attached at the connector site 13. The frame ground planes of the cable 10 that, in cooperation with vias 54, surround the logic ground structure and signal lines are thus connected to the device frame ground at each end of the cable assembly. While a particular embodiment of the invention has been illustrated and described, it would be obvious to those skilled in the art that various other combinations and modifications can be made without departing from the scope of the invention. For example, other techniques than plated through vias may be employed to electrically “stitch” together the margins of the frame ground planes and the logic ground planes to effect the common mode and differential mode shielding for EMI control while maintaining the flex cable characteristics for optimum external connection of electronic devices. It is therefore intended to cover in the appended claims all such combinations and modifications that are within the scope of this invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>Electronic systems composed of multiple devices housed in separate enclosures commonly require external signal interconnects between devices. These systems require that integrated EMC shielding be provided in the flexible cabling extending between enclosures. It is not unusual to find that the external connecting cables are among the largest structures in the system, with the result that common mode currents on these cables are almost always the source of an EMI (electromagnetic interference) problem. To control both differential mode and common mode signals it is necessary to provide both logic ground shielding about the signal lines and secondary frame ground shielding about the logic ground shielding. High performance double shielded coaxial cables are a solution, but are too bulky and require large radius bends and as a result are not suitable for use in current state of the art devices that are continuously attempting to achieve smaller, more compact device sizes. | <SOH> SUMMARY OF THE INVENTION <EOH>This invention provides integrated EMC shielding and grounding for flex cables allowing them to be used externally of device enclosures to afford interconnection. The high density flexible interconnecting cable includes a combination of high performance signals enclosed within and referencing surrounding logic ground planes, surrounded by frame ground shield layers which are viaed together at the external boundaries of the cable throughout the cable's entire length, thus forming an external cable shield. These outer frame ground layers are then physically connected to the frame or chassis ground of the connected device at both the source and termination locations of the cable. This combination of surrounding the signals with both logic ground and then frame ground controls both the differential mode and common mode EMI, necessary for high performance EMI shielding, as well as providing the controlled impedance necessary for signal integrity in a high speed interconnect environment. The advantages of this flat flex cable design is high performance EMI shielding of a high density pin count interconnect that can be used where a small bend radius is required while still retaining enough flexibility for concurrent maintenance. | 20050120 | 20060808 | 20060720 | 67451.0 | H01R13648 | 0 | NGUYEN, KHIEM M | FLEXIBLE CABLE INTERCONNECT WITH INTEGRATED EMC SHIELDING | UNDISCOUNTED | 0 | ACCEPTED | H01R | 2,005 |
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11,038,781 | ACCEPTED | Method and apparatus to stimulate the immune system of a biological entity | A system and method for stimulating the immune systems of biological entities in an environment are disclosed. Pulsed electrical currents are generated using an electric current generator. The pulsed electrical currents are fed through an arrangement of electrically conductive material such that magnetic energy is emitted from the arrangement into the environment. The arrangement of electrically conductive material is designed such that an intensity of the emitted magnetic energy varies across at least one spatial dimension of the environment. Certain embodiments of the arrangement, which have width-to-length ratios of approximately 0.6, tend to provide variations in the intensity of the magnetic energy field which are very good for stimulating the immune systems of the biological entities. | 1. A system for stimulating immune systems of biological entities in an environment, said system comprising: at least one electric current generator providing a source of pulsed electrical current; and at least one continuous coil of electrically conductive material having a first end and a second end, both of said ends being connected to said at least one generator to form a closed circuit such that said at least one coil emits a spatially non-uniform pulsed magnetic field into said environment in response to said pulsed electrical current to stimulate said immune systems as said biological entities move within said environment, and wherein a configuration of said at least one coil comprises a plurality of turns of said conductive material in substantially a single spatial plane, and wherein said coil has an overall width-to-length ratio of between 0.4 and 0.8. 2. The system of claim 1 wherein said biological entities include at least one of humans, animals, and plants. 3. The system of claim 1 wherein an intensity of said magnetic field varies non-linearly across at least one spatial dimension of said at least one coil, said at least one spatial dimension being parallel to said single spatial plane. 4. The system of claim 3 wherein said intensity of said magnetic field varies through a range of about 0.5 to 30 Gauss across said at least one spatial dimension at a predetermined distance from said spatial plane. 5. The system of claim 1 wherein a pulse frequency of said pulsed magnetic field is in a range of 0.5 to 30 Hertz. 6. The system of claim 5 wherein said pulse frequency is incremented and/or decremented over time. 7. The system of claim 1 wherein said at least one coil is positioned at a depth of between 1.0 and 30 inches below a surface of said environment. 8. The system of claim 1 wherein said environment is selected from a group consisting of livestock yards, gardens, orchards, athletic grounds, and play grounds. 9. The system of claim 1 wherein said environment is selected from a group consisting of ponds, lakes, swimming pools, whirl pools, hot tubs, and aquariums. 10. The system of claim 1 wherein said at least one coil is insulated by a non-conductive material. 11. The system of claim 1 wherein said at least one electric current generator comprises a programmable subsystem which may be programmed to control at least an intensity and a pulsed frequency of said electrical current. 12. The system of claim 1 wherein said width-to-length ratio is approximately 0.6. 13. The system of claim 1 wherein a maximum intensity of said spatially non-uniform pulsed magnetic field occurs approximately at a center of said coil. 14. The system of claim 5 wherein a duty cycle of said pulse frequency is approximately 50%. 15. A system for stimulating immune systems of biological entities in an environment, said system comprising: at least one electric current generator providing a source of pulsed electrical current; and at least one arrangement of electrically conductive material having a first end and a second end, both of said ends being connected to said at least one generator to form a closed circuit such that said at least one arrangement emits a spatially non-uniform pulsed magnetic field into said environment in response to said pulsed electrical current to stimulate said immune systems as said biological entities move within said environment, and wherein a configuration of said at least one arrangement comprises a plurality of substantially parallel segments of said conductive material forming a flat, substantially rectangular grid having an overall width-to-length ratio of between 0.4 and 0.8. 16. The system of claim 15 wherein said biological entities include at least one of humans, animals, and plants. 17. The system of claim 15 wherein an intensity of said magnetic field varies non-linearly across at least one spatial dimension of said rectangular grid, said at least one spatial dimension being parallel to a spatial plane containing said segments of said rectangular grid. 18. The system of claim 17 wherein said intensity of said magnetic field varies through a range of about 0.5 to 30 Gauss across said at least one spatial dimension at a predetermined distance from said spatial plane. 19. The system of claim 15 wherein a pulse frequency of said pulsed magnetic field is in a range of 0.5 to 30 Hertz. 20. The system of claim 19 wherein said pulse frequency in incremented and/or decremented over time. 21. The system of claim 15 wherein said at least one arrangement is positioned at a depth of between 1.0 and 30 inches below a surface of said environment. 22. The system of claim 15 wherein said environment is selected from a group consisting of livestock yards, gardens, orchards, athletic grounds, and play grounds. 23. The system of claim 15 wherein said environment is selected from a group consisting of ponds, lakes, swimming pools, whirl pools, hot tubs, and aquariums. 24. The system of claim 15 wherein said at least one arrangement of electrically conductive material is insulated by a non-conductive material. 25. The system of claim 15 wherein said at least one electric current generator comprises a programmable subsystem which may be programmed to control at least an intensity and a pulsed frequency of said electrical current. 26. The system of claim 15 wherein said width-to-length ratio is approximately 0.6. 27. The system of claim 15 wherein a maximum intensity of said spatially non-uniform pulsed magnetic field occurs approximately at a center of said coil. 28. The system of claim 19 wherein a duty cycle of said pulse frequency is approximately 50%. 29. A method for stimulating immune systems of biological entities in an environment, said method comprising: positioning at least one arrangement of electrically conductive material below a surface of said environment; connecting said at least one arrangement of said electrically conductive material to at least one electric current generator to form a closed circuit through said arrangement; generating a pulsed electrical current with said generator such that said pulsed electrical current propagates through said arrangement from a first end of said arrangement to a second end of said arrangement, and wherein said arrangement emits pulsed magnetic energy into said environment in response to said pulsed electrical current such that an intensity of said pulsed magnetic energy is non-uniform across at least one spatial dimension of said arrangement to stimulate said immune systems as said biological entities move within said environment. 30. The method of claim 29 wherein said biological entities include at least one of humans, animals, and plants. 31. The method of claim 29 wherein said at least one arrangement comprises at least one continuous coil of electrically conductive material having a first end and a second end such that said pulsed electrical current is conducted from said first end to said second end, and wherein a configuration of said at least one coil comprises a plurality of spiraling turns of said conductive material forming a flat, substantially oval surface having an overall width-to-length ratio of between 0.4 and 0.8. 32. The method of claim 29 wherein said at least one arrangement comprises at least one continuous coil of electrically conductive material having a first end and a second end such that said pulsed electrical current is conducted from said first end to said second end, and wherein a configuration of said at least one coil comprises a plurality of winding turns of said conductive material forming a flat, substantially rectangular surface having an overall width-to-length ratio of between 0.4 and 0.8. 33. The method of claim 29 wherein said at least one arrangement comprises a plurality of electrically conductive wire segments, said arrangement having a first end and a second end such that said pulsed electrical current is conducted from said first end to said second end, and wherein said wire segments are substantially parallel to each other forming a flat, substantially rectangular grid having an overall width-to-length ratio of between 0.4 and 0.8. 34. The method of claim 29 wherein said intensity of said magnetic energy varies through a range of about 0.5 to 30 Gauss across said at least one spatial dimension at a predetermined distance from a surface of said arrangement. 35. The method of claim 29 wherein said magnetic energy is pulsed at a rate of between 0.5 and 30 Hertz. 36. The method of claim 35 wherein said magnetic energy is pulsed at a rate that varies over time. 37. The method of claim 29 wherein said arrangement is positioned at a depth of between 1.0 and 30 inches below said surface of said environment. 38. The method of claim 29 wherein said environment is selected from a group consisting of livestock yards, gardens, orchards, athletic grounds, and play grounds. 39. The method of claim 29 wherein said environment is selected from a group consisting of ponds, lakes, swimming pools, whirl pools, hot tubs, and aquariums. 40. The method of claim 29 further comprising insulating said at least one arrangement with a non-conductive material. 41. The method of claim 29 wherein said generator comprises a programmable subsystem which may be programmed to control at least an intensity and a pulsed frequency of said electrical current. 42. The method of claim 31 wherein said width-to-length ratio is approximately 0.6. 43. The method of claim 32 wherein said width-to-length ratio is approximately 0.6. 44. The method of claim 33 wherein said width-to-length ratio is approximately 0.6. 45. The method of claim 29 wherein a maximum intensity of said spatially non-uniform pulsed magnetic energy occurs approximately at a center of said arrangement. 46. The method of claim 35 wherein a duty cycle of said pulsed rate is approximately 50%. 47. A system for stimulating immune systems of biological entities in an environment, said system comprising: at least one electric current generator providing a source of pulsed electrical current; and at least one continuous coil of electrically conductive material having a first end and a second end, both of said ends being connected to said at least one generator to form a closed circuit such that said at least one coil emits a spatially non-uniform pulsed magnetic field into said environment in response to said pulsed electrical current to stimulate said immune systems as said biological entities move within said environment, and wherein a configuration of said at least one coil comprises a plurality of parallel straight segments of said conductive material, being substantially of a same length, and a plurality of curved segments of said conductive material, and wherein said continuous coil spirals outward from a central position of said coil in substantially a single spatial plane. 48. The system of claim 47 wherein said coil has an overall width-to-length ratio of between 0.4 and 0.8. 49. The system of claim 47 wherein said biological entities include at least one of humans, animals, and plants. 50. The system of claim 47 wherein an intensity of said magnetic field varies non-linearly across at least one spatial dimension of said at least one coil, said at least one spatial dimension being parallel to said single spatial plane. 51. The system of claim 50 wherein said intensity of said magnetic field varies through a range of about 0.5 to 30 Gauss across said at least one spatial dimension at a predetermined distance from said spatial plane. 52. The system of claim 47 wherein a pulse frequency of said pulsed magnetic field is in a range of 0.5 to 30 Hertz. 53. The system of claim 52 wherein said pulse frequency in incremented and/or decremented over time. 54. The system of claim 47 wherein said at least one coil is positioned at a depth of between 1.0 and 30 inches below a surface of said environment. 55. The system of claim 47 wherein said environment is selected from a group consisting of livestock yards, gardens, orchards, athletic grounds, and play grounds. 56. The system of claim 47 wherein said environment is selected from a group consisting of ponds, lakes, swimming pools, whirl pools, hot tubs, and aquariums. 57. The system of claim 47 wherein said at least one coil is insulated by a non-conductive material. 58. The system of claim 47 wherein said at least one electric current generator comprises a programmable subsystem which may be programmed to control at least an intensity and a pulsed frequency of said electrical current. 59. The system of claim 48 wherein said width-to-length ratio is approximately 0.6. 60. The system of claim 47 wherein a maximum intensity of said spatially non-uniform pulsed magnetic field occurs approximately at a center of said coil. 61. The system of claim 52 wherein a duty cycle of said pulse frequency is approximately 50%. 62. A system for stimulating immune systems of biological entities in an environment, said system comprising: at least one electric current generator providing a source of pulsed electrical current; and at least one continuous coil of electrically conductive material having a first end and a second end, both of said ends being connected to said at least one generator to form a closed circuit such that said at least one coil emits a spatially non-uniform pulsed magnetic field into said environment in response to said pulsed electrical current to stimulate said immune systems as said biological entities move within said environment, and wherein a configuration of said at least one coil comprises a first plurality of parallel straight segments of said conductive material and a second plurality of parallel straight segments of said conductive material being substantially perpendicular to said first plurality of segments, and wherein said continuous coil winds outward from a central position of said coil in substantially a single spatial plane. 63. The system of claim 62 wherein said coil has an overall width-to-length ratio of between 0.4 and 0.8. 64. The system of claim 62 wherein said biological entities include at least one of humans, animals, and plants. 65. The system of claim 62 wherein an intensity of said magnetic field varies non-linearly across at least one spatial dimension of said at least one coil, said at least one spatial dimension being parallel to said single spatial plane. 66. The system of claim 65 wherein said intensity of said magnetic field varies through a range of about 0.5 to 30 Gauss across said at least one spatial dimension at a predetermined distance from said spatial plane. 67. The system of claim 62 wherein a pulse frequency of said pulsed magnetic field is in a range of 0.5 to 30 Hertz. 68. The system of claim 67 wherein said pulse frequency in incremented and/or decremented over time. 69. The system of claim 62 wherein said at least one coil is positioned at a depth of between 1.0 and 30 inches below a surface of said environment. 70. The system of claim 62 wherein said environment is selected from a group consisting of livestock yards, gardens, orchards, athletic grounds, and play grounds. 71. The system of claim 62 wherein said environment is selected from a group consisting of ponds, lakes, swimming pools, whirl pools, hot tubs, and aquariums. 72. The system of claim 62 wherein said at least one coil is insulated by a non-conductive material. 73. The system of claim 62 wherein said at least one electric current generator comprises a programmable subsystem which may be programmed to control at least an intensity and a pulsed frequency of said electrical current. 74. The system of claim 63 wherein said width-to-length ratio is approximately 0.6. 75. The system of claim 62 wherein a maximum intensity of said spatially non-uniform pulsed magnetic field occurs approximately at a center of said coil. 76. The system of claim 67 wherein a duty cycle of said pulse frequency is approximately 50%. | CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE This U.S. patent application is a continuation-in-part (CIP) of pending U.S. patent application Ser. No. 10/114,656, filed on Apr. 2, 2002 which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/281,203 filed Apr. 3, 2001, both applications hereby incorporated by reference. TECHNICAL FIELD Certain embodiments of the present invention relate to stimulating the immune system of biological entities. More particularly, certain embodiments of the present invention relate to a system and method to stimulate the immune system of biological entities moving in an environment through application of pulsed magnetic energy. BACKGROUND OF THE INVENTION Use of magnetic energy to increase physiological performance of organisms has long been attempted. However, many of these techniques have been limited to belts, pads or mats which apply magnetic or electromagnetic energy to the person or other organism. Problems inherent in these techniques include the necessity for the organism to wear the belt or pad, and the necessity for a portable power source in order to generate magnetic energy. Furthermore, these techniques do not effect the environment surrounding the organism. Accordingly, there is a demand for an apparatus and method of applying pulsed magnetic energy to an organism (i.e., a biological entity) and its surrounding environment that is without the aforementioned disadvantages. Further limitations and disadvantages of conventional, traditional, and proposed approaches will become apparent to one of skill in the art, through comparison of such systems and methods with the present invention as set forth in the remainder of the present application with reference to the drawings. BRIEF SUMMARY OF THE INVENTION An embodiment of the present invention comprises a system for stimulating immune systems of living biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end, both of the ends being connected to the at least one generator to form a closed circuit such that the at least one coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. Also, a configuration of the at least one coil comprises a plurality of turns of the conductive material in substantially a single spatial plane, and wherein the coil has an overall width-to-length ratio of between 0.4 and 0.8. Another embodiment of the present invention comprises a system for stimulating immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one arrangement of electrically conductive material having a first end and a second end, both of the ends being connected to the at least one generator to form a closed circuit such that the at least one arrangement emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. Also, a configuration of the at least one arrangement comprises a plurality of substantially parallel segments of the conductive material forming a flat, substantially rectangular grid having an overall width-to-length ratio of between 0.4 and 0.8. A further embodiment of the present invention comprises a method for stimulating immune systems of living biological entities in an environment. The method comprises positioning at least one arrangement of electrically conductive material below a surface of the environment and connecting the at least one arrangement of electrically conductive material to at least one electric current generator to form a closed circuit through the arrangement. The method further comprises generating a pulsed electrical current with the generator such that the pulsed electrical current propagates through the arrangement from a first end of the arrangement to a second end of the arrangement. The arrangement emits pulsed magnetic energy into the environment in response to the pulsed electrical current such that an intensity of the pulsed magnetic energy is non-uniform across at least one spatial dimension of the arrangement to stimulate the immune systems as the biological entities move within the environment. Another embodiment of the present invention includes a system for stimulating the immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end where both ends are connected to the generator to form a closed circuit such that the coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. A configuration of the coil includes a plurality of parallel straight segments of the conductive material, being substantially of the same length, and a plurality of curved segments of the conductive material. The continuous coil spirals outward from a central position of the coil in substantially a single spatial plane. A further embodiment of the present invention includes a system for stimulating the immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end where both ends are connected to the generator to form a closed circuit such that the coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. A configuration of the coil comprises a first plurality of parallel straight segments of the conductive material and a second plurality of parallel straight segments of the conductive material being substantially perpendicular to the first plurality of segments. The continuous coil winds outward from a central position of the coil in substantially a single spatial plane. These and other advantages and novel features of the present invention, as well as details of illustrated embodiments thereof, will be more fully understood from the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a first exemplary embodiment of a system for applying pulsed magnetic energy to an aquatic environment, in accordance with various aspects of the present invention. FIG. 2 illustrates a first exemplary embodiment of a flat coil used to generate magnetic energy, in accordance with various aspects of the present invention. FIGS. 3A-3C illustrate various views of an embodiment of the flat coil of FIG. 2, clearly showing the spacing between the coil turns, in accordance with various aspects of the present invention. FIG. 4 illustrates an exemplary simulated graph of how a magnetic field intensity generated by the coil of FIG. 2 may be expected to vary non-linearly across a spatial dimension of the coil of FIG. 2, in accordance with various aspects of the present invention. FIG. 5 illustrates an exemplary graph of measured data of how a magnetic field intensity generated by the coil of FIGS. 3A-3C varies across three spatial dimensions of the coil of FIGS. 3A-3C, in accordance with various aspects of the present invention. FIG. 6 is a flowchart of an embodiment of a method to stimulate immune systems of biological entities in an environment, in accordance with various aspects of the present invention. FIG. 7 illustrates a second exemplary embodiment of a flat coil used to generate magnetic energy, in accordance with various aspects of the present invention. FIG. 8 illustrates a second exemplary embodiment of a system for applying pulsed magnetic energy to a stock pen environment, in accordance with various aspects of the present invention. FIG. 9 illustrates a third exemplary embodiment of a system for applying pulsed magnetic energy to a garden environment, in accordance with various aspects of the present invention. FIG. 10 illustrates a fourth exemplary embodiment of a system for applying pulsed magnetic energy to a sports environment, in accordance with various aspects of the present invention. FIG. 11 illustrates a fifth exemplary embodiment of a system for applying pulsed magnetic energy to a golf course environment, in accordance with various aspects of the present invention. FIG. 12 illustrates exemplary resultant current pulses that may be produced in the coil of FIG. 2 when applying an exemplary DC pulsed voltage waveform to the coil of FIG. 2, in accordance with an embodiment of the present invention. FIG. 13 illustrates exemplary resultant current pulses produced in the coil of FIGS. 3A-3C when applying an exemplary DC pulsed voltage waveform to the coil of FIGS. 3A-3C, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the various embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. FIG. 1 illustrates a first exemplary embodiment of a system for applying pulsed magnetic energy to an aquatic environment, in accordance with various aspects of the present invention. Shown generally at 10, the embodiment of FIG. 1 includes a water reservoir 12, such as an aquarium, a pool, a pond or some other body of water. Below water reservoir 12 is placed electric wiring 16. In FIG. 1 electric wiring 16 is shown as a continuous coil of wiring, originating from the electric current generator 14 at a first end 17 and connecting back to the electric current generator 14 at a second end 19 to form a closed circuit. The electrical wiring 16 is placed over a substantial area of the water reservoir 12, at 1 to 30 inches below the bottom surface of the water reservoir 12, and is insulated from the surrounding elements and cross currents from other cables that may be present. If the water reservoir 12 has sides, such as in a pool, electric wiring 16 can also be placed behind the surface of the sides of reservoir 12. Electric wiring 16 is insulated by neutral materials, such as plastics, that will insulate the electric wiring 16, yet not produce a significant charge in the surrounding soil or substance. The electric wiring may be coated with an insulating material or may be placed in a non-conductive conduit, for example. Further, highly shielded electrical wire (e.g., using a conductive shield) is not desired as it decreases the capacity of diffusion of the pulsed magnetic energy into the aquatic environment. A pulsed DC voltage waveform is supplied to the electric wiring 16, and is controlled by the electric current generator 14. Pulsed current supplied by the generator 14 propagates from a first end 17 of the coil 16 to a second end 19 of the coil 16 in a closed loop in response to the pulsed DC voltage waveform. That is, both ends 17 and 19 of the coil 16 are connected to output terminals of the generator 14. Alternatively, pulsed current supplied by the generator 14 may propagate from the second end 19 to the first end 17. Optionally, an air pump 18 and perforated air hose 20 may be included in the system embodied in FIG. 1. Air pump 18 and air hose 20 provide an oxygen source to the water within reservoir 12, thus, aerating the water and increasing the oxygen concentration of the water. In use, pulsed electrical current is applied to the electric wiring 16 by an electric current generator 14. Various electronic components may be utilized to generate electric current for use in this system and may include a computer controlled subsystem, for example, to control the intensity and pulsed frequency of the emitted magnetic energy. An electric current generator typically includes a power transformer, a rectifier and filter circuit, and an electronic switching circuit. For example, an electric current generator may be plugged into a 240 VAC single phase power source and output a pulsed DC voltage waveform having a maximum peak amplitude of, for example, 80 VDC. In accordance with an embodiment of the present invention, the magnetic energy emitted from the wiring 16 has magnetic field components in the range of about 0.5 to 30 Gauss, and the frequency range of the pulses is between 0.5 and 30 Hertz. Concurrently, air pump 18 pumps air through hose 20 to increase the oxygen concentration of the water. The water in free motion around the air bubbles is energized to a higher state because of the application of the pulsed magnetic energy, and thus may become even more saturated with oxygen. Application of the magnetic energy to the reservoir 12 provides for application of magnetic energy to both plants and animals (i.e., biological entities) situated within the aquatic system. The affected plants and animals exhibit enhanced physiologic effects such as increased growth and overall health, for example, due to stimulation of the immune systems of the plants and animals. Furthermore, the highly oxygenated and energized water can then be utilized for watering plants which may not be directly exposed to the magnetic energy. Electric current flows in a wire when a potential difference (i.e., a voltage) is applied across both ends of the wire. When electric current flows through a wire, a magnetic field is set up or emanates from the wire. If the wire is arranged in a coiled or grid-like configuration, for example, the magnetic fields from the various turns of the coil may combine constructively and destructively to form a spatially non-uniform magnetic field profile. FIG. 2 illustrates an exemplary embodiment of a flat coil 200 used to generate magnetic energy, in accordance with various aspects of the present invention. The coil is a continuous coil of electrically conductive material (e.g., copper wire) having a first end 201 and a second end 202. Both ends 201 and 202 are connected to at least one generator (e.g. generator 14 in FIG. 1) to form a closed circuit. The generator creates a pulsed voltage waveform (e.g., a DC pulsed waveform) that results in pulsed electrical currents that propagate through the coil 200 from the first end 201 to the second end 202 (or vice versa). When the current pulses propagate through the coil 200, magnetic energy is emitted from the coil in the form of a pulsed magnetic field. When the coil is placed in an environment such as, for example, a swimming pool, a livestock yard, a garden, orchards, an athletic ground, a play ground, a pond, a lake, a whirl pool, a hot tub, or an aquarium, the magnetic energy is dispersed into the environment. The magnetic energy tends to stimulate the immune systems of biological entities (e.g., plants, animals, and humans) that are moving within the environment. In accordance with an embodiment of the present invention, a configuration of the coil 200 comprises a plurality of spiraling turns of a conductive material such as, for example, copper wire. The spiraling turns do not necessarily follow a strictly mathematical spiral, but rather, the turns spiral at least in the sense that the turns wrap around on each other from the inside (i.e., from a central position 203 of the coil 200) to the outside of the coil 200. The configuration forms a flat, substantially oval surface having a width-to-length ratio of between 0.4 and 0.8. Ideally, the width-to-length ratio is 0.618 which is the “golden mean” ratio found in many instances of nature. For example, the width-to-length ratio of the coil 200 shown in FIG. 2 is 84.1232 inches divided by 156 inches which is a ratio of 0.539. The coil 200 of FIG. 2 has approximately 37 turns spaced at approximately 1 inch separation. In accordance with an embodiment of the present invention, the coil 200 comprises 8 Gage solid copper wire having a resistance of about 0.6 ohms per 1000 feet. The configuration of the coil 200 includes a plurality of parallel straight segments 210 of insulated copper wire being of substantially the same length, and a plurality of curved segment of insulated copper wire 220. The segments 210 and 220 are not discrete in the sense that they must be connected to form the coil 200. Instead, the coil 200 is a continuous piece of copper wire. However, in an alternative embodiment the coil 200 could be made from discrete segments that are connected together by, for example, welding or soldering. The configuration of the coil 200 is such that the plurality of turns of the coil are substantially in a single spatial plane, which gives the coil 200 its flat shape. In accordance with the embodiment of FIG. 2, the coil emits a magnetic field at least perpendicular to the surface of the coil (i.e., out of the page of FIG. 2). The intensity of the magnetic field varies (i.e., is non-uniform) across the coil 200, in a spatial dimension which is parallel to the surface of the coil 200. The variation may be non-linear, in accordance with certain embodiments of the present invention. Therefore, as a biological entity moves within the environment in which the coil 200 is placed, the biological entity experiences the variations of the magnetic field. The variations stimulate the immune system of the biological entity. Typically, the coil 200 is insulated using a non-conducting material such as a plastic, to prevent direct conduction of the electrical currents into the surrounding environment. FIGS. 3A-3C illustrate various views of an embodiment of the flat coil 200 of FIG. 2, clearly showing the spacing between the coil turns, in accordance with various aspects of the present invention. The coil 200 shown in FIG. 3A is mounted on a surface 310 (e.g., a plywood board) using plastic clips to secure the wiring of the coil 200. FIG. 3B shows a curved section of the coil 200 with the spacing 320 between the curved segments being about one inch. FIG. 3C shows a straight section of the coil 200 with the spacing 330 between the straight and parallel segments being about one inch. FIG. 4 illustrates an exemplary simulated graph 400 of how a magnetic field intensity Bm 401 generated by the coil 200 of FIG. 2 may be expected to vary non-linearly across a spatial dimension 402 of the coil of FIG. 2 (distance across coil), in accordance with various aspects of the present invention. The peak magnetic intensity 403 occurs at the center of the coil 200. It is the configuration of the coil (e.g., shape, dimensions, spacing) that largely determines the shape of the spatially non-uniform magnetic field intensity. For example, the graph 400 of FIG. 4 may represent the variation in magnetic field intensity Bm across the width dimension 240 of the coil 200 and through a first center axis 250 of the coil 200 (see FIG. 2). FIG. 5 illustrates an exemplary graph 500 of measured data of how a magnetic field intensity 501 generated by the coil 200 of FIGS. 3A-3C varies across three spatial dimensions of the coil 200 of FIGS. 3A-3C, in accordance with various aspects of the present invention. The data set 510 shows the variation in measured magnetic field intensity above (e.g., 18 inches) the coil 200 and across the length dimension 260 of the coil 200 along the axis 265 which includes the physical center point 205 of the coil 200 (see FIG. 2). The coil center 540 is shown on the distance axis 550 in FIG. 5. The data set 520 shows the variation in measured magnetic field intensity above (e.g., 18 inches) above the coil 200 and across the width dimension 240 of the coil 200 along the axis 250 which includes the physical center point 205 of the coil 200. The data set 530 shows the variation in measured magnetic field intensity above (e.g., 18 inches) the coil 200 and across a diagonal dimension of the coil 200 along the axis 270 which includes the physical center 205 of the coil 200. The direction of the magnetic field intensities 510, 520, and 530 shown in the graph 500 is perpendicular to the flat surface of the coil 200. The absolute magnitude of the magnetic field intensities is a function of distance away from the surface or plane of the coil. In general, the magnetic field intensity decreases at points further away from the surface or plane of the coil. Notice that the magnetic field intensity 560 at the physical center of the coil is the same for all three data sets 510, 520, and 530 since the center corresponds to the same physical point in all three cases. For example, if the coil 200 is placed flat and just beneath the bottom surface of a swimming pool (e.g., 1 to 30 inches), the magnetic field intensity 501 of the data sets 510, 520, and 530 will emanate above the coil into the water of the pool. As a swimmer swims through the pool across the coil (e.g., parallel to the surface of the coil), the swimmer will experience the magnetic variations of the magnetic field generated by the coil which stimulate the swimmer's immune system. In accordance with an embodiment of the present invention, the magnetic field is a pulsed magnetic field having a pulsed frequency of between 0.5 and 30 Hertz, and the intensity of the magnetic fields 510, 520, and 530 at a predetermined distance from the surface of the coil (e.g., 18 inches) vary through a range of about 0.5 to 30 Gauss across at least one spatial dimension of the coil 200. The electric current generator may comprise a programmable subsystem (e.g., a programmable logic controller or a computer-based subsystem such as a personal computer) which may control the frequency and intensity of the current pulses and, therefore, of the magnetic energy pulses. FIG. 6 is a flowchart of an embodiment of a method 600 to stimulate immune systems of biological entities in an environment, in accordance with various aspects of the present invention. In step 610, at least one arrangement of electrically conductive material is positioned below a surface of an environment (for example, referring to FIG. 1, the coil 16 is positioned below the surface of the aquatic environment 12). In step 620, the at least one arrangement of electrically conductive material is connected to at least one electric current generator to form a closed circuit through the arrangement (for example, referring to FIG. 1, the ends 17 and 19 of the coil 16 are connected to electric terminals of the generator 14). In step 630, a pulsed electrical current is generated with the generator such that the pulsed electrical current propagates through the arrangement from a first end (e.g., end 19 in FIG. 1) of the arrangement to a second end (e.g., end 17 in FIG. 1) of the arrangement, and wherein the arrangement emits pulsed magnetic energy into the environment in response to the pulsed electrical current such that an intensity of the pulsed magnetic energy is non-uniform across at least one spatial dimension of the arrangement (e.g., see the non-uniform magnetic fields of FIGS. 4 and 5) to stimulate the immune systems as the biological entities move within the environment. FIG. 7 illustrates a second exemplary embodiment of a flat coil 700 used to generate magnetic energy, in accordance with various aspects of the present invention. The coil 700 has a first end 701 and a second end 702 and comprises a first plurality of vertically oriented, parallel straight segments 710 of conductive wire and a second plurality 720 of horizontally oriented, parallel straight segments 720 of conductive wire which are substantially perpendicular to the first plurality of segments. The coil 700 is a continuous wire, winding outward from a central position 730 of the coil 700 in substantially a single spatial plane forming a flat, rectangular coil (i.e., a coil forming a flat, rectangular surface). The coil 700 of FIG. 7 is similar to the coil 200 of FIG. 2 except the curved segments of FIG. 2 are replaced with the straight segments 720 of FIG. 7 and the straight segments 710 are not all of the same length. Referring now to FIG. 8, there is shown a second exemplary embodiment a system of the present invention, illustrating the application of pulsed magnetic energy to livestock animal pens. In this second embodiment, there is a stock pen 830 which can be used to retain any type of livestock animal or poultry. Further, it should be understood that such a stock pen can be enclosed in buildings or open fields. Electrical wiring 820 extends below the surface and laterally across first stock pen 830 to cover at least a substantial area of stock pen 830. The configuration of the electrical wiring 820 includes a plurality of substantially parallel segments of conductive material (e.g., segments of wiring) forming a flat, substantially rectangular grid. As in the first embodiment 10 of FIG. 1, electrical wiring 820 is comprised of electrical wiring having neutral insulating materials, and is placed under the surface of the selected area at a preferred depth of 1 to 30 inches. Electric current generator 810 generates and transmits pulsed electric currents through electric wiring 820. In accordance with an embodiment of the present invention, the width-to-length ratio of the substantially rectangular grid is between 0.4 and 0.8. Optionally, this system may also include a water tank 840 for the watering of the animals. An air pump 850 may be used to pump air into the water tank 840 through hose 860. Aeration of water tank 840 by pump 850 increases the oxygen concentration of the water held within water tank 840. In the embodiment of FIG. 8, the electrical wiring 820 forms a type of horizontal grid configuration across the stock pen 830. Pulsed current flows from the generator 810 through the various branches of the grid of wiring 820 and back to the generator 810, emitting pulsed magnetic energy (i.e., magnetic fields) into the environment of the stock pen 830. If the stockyard is enclosed, the electric wiring is buried at a depth between 1 and 30 inches within the dirt or other flooring material, such as concrete, for example. Again, a spatially non-uniform magnetic field is generated across the grid. However, the non-uniformity may be substantially different from that shown in FIGS. 4 and 5 due largely to the different configuration of the wiring 820 from that of the coil 200 of FIG. 2. However, a coil of the configuration of that of FIG. 1 or FIG. 2, or other configurations, could be used in the stockyard environment instead. Now referring to FIG. 9, there is shown a third exemplary embodiment of a system of the present invention illustrating the application of pulsed magnetic energy to a plant bio-system 900, such as a garden. The plant based bio-system may include, for example, a grain plot 910, fruit or other trees 920, plants 930 and/or flowers 940. The plants may either be grown within the ground itself or within planting containers such as pots and the like. The environment 900 may optionally also include a water reservoir 950, which is aerated by hose 960 and air pump 970 to increase the oxygen concentration of the water held within reservoir 950. Pulsed magnetic energy is generated by an electric current generator 980 applying pulsed currents to electric wiring grid 990. Electric wiring grid 990 is positioned to cover at least a substantial portion of environment 900, and is placed below the surface of environment 900, at a depth of 1 to 30 inches. The plants affected by the application of the pulsed magnetic energy exhibit improved physiological effects such as improved and more rapid growth, and better overall health for example. Shown in FIG. 10 is yet another exemplary embodiment of the present invention, illustrating applying magnetic energy to an athletic playing surface 1000, such as, for example a basketball court, a football field, a soccer field, a swimming pool, playgrounds or other playing surfaces. Electrical wiring 1010 is placed below playing surface 1000 at a preferred depth of between 1 and 30 inches. Electrical current generator 1020 generates and conducts electrical currents through electric wiring 1010 to create and diffuse the resultant magnetic energy throughout playing surface 1000. The magnetic energy is applied to those persons playing or competing on playing surface 1000. Upon application of the magnetic energy, humans may experience higher energy levels for longer periods of time, reduced fatigue, less muscle strain and soreness, in addition to increased concentration and precision in playing the particular sport. Referring now to FIG. 11, there is shown yet another exemplary embodiment of the present invention, illustrating application of magnetic energy to a golf course hole. This embodiment includes a tee box 1110, a green 1120 and/or optionally a water reservoir 1130. Below tee box 1110 is placed electrical wiring 1140, which is placed at a depth of 1 to 30 inches. Electrical wiring 1150 is also placed below golf green 1120 at a preferred depth of 1 to 30 inches. If water reservoir 1130 is used, electrical wiring 1160 is positioned below the bottom of reservoir 1130 at a depth of 1 to 30 inches for emission of magnetic energy. Air pump 1195 and air hose 1196 may optionally be used to pump air into the water reservoir 1130 to increase the oxygen content. Treated water from reservoir 1130 may be used to water the golf course fairways, greens, or other plants associated with the course as to achieve the benefits as described above in relation to the plant based bio-system embodiment. Electric current generators 1170, 1180 and 1190 produce pulsed electric currents such that magnetic energy is emitted from electrical wiring 1140, 1160, and 1150 respectively. Optionally, a single generator can control the emission of magnetic energy from electrical wiring 1140, 1160, and 1150. As with the above described embodiments, electric current generators 1170, 1180 and 1190 cause magnetic energy to be emitted having magnetic field components about in the range of 0.5 to 30 Gauss, and the frequency range of the pulses is between 0.5 and 30 Hertz. Effects seen through application of the pulsed magnetic energy to a grass surfaces such as soccer fields, play grounds, football fields, golf greens and tee boxes include more rapid and healthier growth of grass, faster regeneration or repair of divots and ball marks, fewer attacks to these grasses by pests as the grasses are healthier. The human players experience gentle invigoration, increased energy, greater concentration, and less muscle soreness or strain. Increased mental activity and faster healing of wounds has also been noted. Sporting equipment such as golf clubs are not affected by the application of magnetic energy because no sustained electrical current is conducted to the metal portions of the clubs. In use with any of the above embodiments, the characteristics of the magnetic energy remain the same, that is the magnetic energy having magnetic field components about in the range of 0.5 to 30 Gauss, and the frequency range of the pulses between 0.5 and 30 Hertz. In application of pulsed magnetic energy to humans, the magnetic field strength may be adjusted to vary between 4 to 8 Gauss. The placement of the electrical wiring below the surface of the selected area is adjusted to accommodate these parameters. Further, it is important to note that the spacing and arrangement of the electric wiring in the above described embodiments may be altered to achieve certain desired effects. FIG. 12 illustrates exemplary resultant current pulses 1210 and 1220 that may be produced in the coil 200 of FIG. 2 when applying an exemplary DC pulsed voltage waveform 1230 to the coil 200 of FIG. 2, in accordance with an embodiment of the present invention. The pulsed voltage waveform 1230 shown in FIG. 12 is a square voltage waveform having a 50% duty cycle. Other duty cycles are possible as well, in accordance with various embodiments of the present invention. The pulsed voltage waveform 1230 is applied to the coil 200 by a generator (e.g., generator 14 of FIG. 1). The frequency of the pulsed voltage waveform 1230 may be, for example, anywhere between 0.1 Hz and 30 Hz. Depending on the various parameters (e.g., the voltage level, the time constant, the pulsed frequency, etc.) of the system, the resultant pulsed current waveform in the coil may look like that of waveform 1210. Referring to the pulsed current waveform 1210, as the voltage level of the pulsed voltage waveform 1230 increases, the current level in the coil will begin to increase as seen in the segment 1211 of the pulsed current waveform 1210. The curved nature of the rising current level of the segment 1211 is due, at least in part, to the time constant of the system (including the coil) which is determined by inductive, capacitive, and resistive factors of the system. In the pulsed current waveform 1210, the current level rises continuously until the voltage level of the driving pulsed voltage waveform drops off. When the voltage level of the pulsed voltage waveform 1230 decreases, the current level in the coil will begin to decrease as seen in the segment 1212 of the pulsed current waveform 1210. Again, the curved nature of the falling current level of the segment 1212 is due, at least in part, to the time constant of the system. In the pulsed current waveform 1210, the current level decreases continuously until the voltage level of the driving pulsed voltage waveform again rises. For example, the peak voltage level of the DC pulsed voltage waveform 1230 may be 80 VDC and the resultant peak current level of the pulsed current waveform 1210 may be 100 amps. Referring to the pulsed current waveform 1220, as the voltage level of the pulsed voltage waveform 1230 increases, the current level in the coil will begin to increase as seen in the segment 1221 of the pulsed current waveform 1220. Again, the curved nature of the rising current level of the segment 1221 is due, at least in part, to the time constant of the system. In the pulsed current waveform 1220, the current level rises and then flattens off to a peak current level 1222 well before the voltage level of the pulsed voltage waveform drops off. This flattening off tends to occur when the peak voltage level 1231 is relatively low. The lower peak voltage level 1231 means that the current will not build to as high a level as it would with a higher peak voltage level driving the coil. Therefore, the pulsed current waveform 1220 reaches its peak level sooner and stays there. When the voltage level of the pulsed voltage waveform 1230 decreases, the current level in the coil will begin to decrease as seen in the segment 1223 of the pulsed current waveform 1220. Again, the curved nature of the falling current level of the segment 1223 is due, at least in part, to the time constant of the system. In the pulsed current waveform 1220, the current level decreases to a zero current level 1224 well before the voltage level of the pulsed voltage waveform increases again. Again, this flattening off tends to occur when the peak voltage level 1231 is relatively low. That is, the current level does not have as far to fall since the peak current level was relatively low. Therefore, the current level reaches zero sooner and flattens off. For example, the peak voltage level of the DC pulsed voltage waveform 1230 may be 20 VDC and the resultant peak current level of the pulsed current waveform 1210 may be 10 amps. FIG. 13 illustrates exemplary resultant current pulses 1310 produced in the coil 200 of FIGS. 3A-3C when applying an exemplary DC pulsed voltage waveform 1320 to the coil 200 of FIGS. 3A-3C, in accordance with an embodiment of the present invention. The pulsed voltage waveform 1320 shown in FIG. 13 is a pseudo-square voltage waveform having a 50% duty cycle. Other duty cycles are possible as well, in accordance with various embodiments of the present invention. The pulsed voltage waveform 1320 tends to droop over the segment 1330 due to the load the coil provides to the generator. Therefore, the pulsed voltage waveform 1320 is not perfectly square. The frequency of the pulsed voltage waveform 1320 may be, for example, anywhere between 0.1 Hz and 30 Hz. Depending on the various parameters (e.g., the voltage level, the time constant, the pulsed frequency, etc.) of the system, the resultant pulsed current waveform in the coil may look like that of waveform 1310. Referring to the pulsed current waveform 1310, as the voltage level of the pulsed voltage waveform 1320 increases, the current level in the coil will begin to increase as seen in the segment 1311 of the pulsed current waveform 1310. The curved nature of the rising current level of the segment 1311 is due, at least in part, to the time constant of the system (including the coil) which is determined by inductive, capacitive, and resistive factors of the system. In the pulsed current waveform 1310, the current level rises continuously until the voltage level of the driving pulsed voltage waveform begins to droop. There is a time delay, however, between when the voltage level begins to droop and when the current level begins to decrease slightly over the segment 1312. When the voltage level of the pulsed voltage waveform 1320 drops off, the current level in the coil will begin to decrease as seen in the segment 1313 of the pulsed current waveform 1310. Again, the curved nature of the falling current level of the segment 1313 is due, at least in part, to the time constant of the system. In the pulsed current waveform 1310, the current level decreases continuously until the voltage level of the driving pulsed voltage waveform again rises. In accordance with various embodiments of the present invention, the systems described herein may be used by incrementing and/or decrementing the pulsed frequency over time. For example, in accordance with an embodiment of the present invention, the pulsed frequency may start at 0.5 Hz and be incremented every one minute by 0.5 Hz until reaching 28 Hz. Then the pulsed frequency may be decremented from 28 Hz back down to 0.5 Hz at a frequency step of 0.5 Hz every minute. Other methods of varying the pulsed frequency over time are possible as well and may be tailored to certain physiological conditions to be treated by stimulating the immune system. In summary, a method and systems are disclosed for stimulating the immune systems of biological entities in an environment. A magnetic energy field is generated such that the magnetic energy field varies non-uniformly in intensity across at least one spatial dimension of the environment. The magnetic energy field is generated using an electric current generator which is connected to a coil or other alternate arrangement of conductive material such as wire. The coil or arrangement is typically placed beneath a surface of the environment. The magnetic energy field is pulsed at a predetermined frequency. While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Use of magnetic energy to increase physiological performance of organisms has long been attempted. However, many of these techniques have been limited to belts, pads or mats which apply magnetic or electromagnetic energy to the person or other organism. Problems inherent in these techniques include the necessity for the organism to wear the belt or pad, and the necessity for a portable power source in order to generate magnetic energy. Furthermore, these techniques do not effect the environment surrounding the organism. Accordingly, there is a demand for an apparatus and method of applying pulsed magnetic energy to an organism (i.e., a biological entity) and its surrounding environment that is without the aforementioned disadvantages. Further limitations and disadvantages of conventional, traditional, and proposed approaches will become apparent to one of skill in the art, through comparison of such systems and methods with the present invention as set forth in the remainder of the present application with reference to the drawings. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>An embodiment of the present invention comprises a system for stimulating immune systems of living biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end, both of the ends being connected to the at least one generator to form a closed circuit such that the at least one coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. Also, a configuration of the at least one coil comprises a plurality of turns of the conductive material in substantially a single spatial plane, and wherein the coil has an overall width-to-length ratio of between 0.4 and 0.8. Another embodiment of the present invention comprises a system for stimulating immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one arrangement of electrically conductive material having a first end and a second end, both of the ends being connected to the at least one generator to form a closed circuit such that the at least one arrangement emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. Also, a configuration of the at least one arrangement comprises a plurality of substantially parallel segments of the conductive material forming a flat, substantially rectangular grid having an overall width-to-length ratio of between 0.4 and 0.8. A further embodiment of the present invention comprises a method for stimulating immune systems of living biological entities in an environment. The method comprises positioning at least one arrangement of electrically conductive material below a surface of the environment and connecting the at least one arrangement of electrically conductive material to at least one electric current generator to form a closed circuit through the arrangement. The method further comprises generating a pulsed electrical current with the generator such that the pulsed electrical current propagates through the arrangement from a first end of the arrangement to a second end of the arrangement. The arrangement emits pulsed magnetic energy into the environment in response to the pulsed electrical current such that an intensity of the pulsed magnetic energy is non-uniform across at least one spatial dimension of the arrangement to stimulate the immune systems as the biological entities move within the environment. Another embodiment of the present invention includes a system for stimulating the immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end where both ends are connected to the generator to form a closed circuit such that the coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. A configuration of the coil includes a plurality of parallel straight segments of the conductive material, being substantially of the same length, and a plurality of curved segments of the conductive material. The continuous coil spirals outward from a central position of the coil in substantially a single spatial plane. A further embodiment of the present invention includes a system for stimulating the immune systems of biological entities in an environment. The system comprises at least one electric current generator providing a source of pulsed electrical current. The system further comprises at least one continuous coil of electrically conductive material having a first end and a second end where both ends are connected to the generator to form a closed circuit such that the coil emits a spatially non-uniform pulsed magnetic field into the environment in response to the pulsed electrical current to stimulate the immune systems as the biological entities move within the environment. A configuration of the coil comprises a first plurality of parallel straight segments of the conductive material and a second plurality of parallel straight segments of the conductive material being substantially perpendicular to the first plurality of segments. The continuous coil winds outward from a central position of the coil in substantially a single spatial plane. These and other advantages and novel features of the present invention, as well as details of illustrated embodiments thereof, will be more fully understood from the following description and drawings. | 20050119 | 20080304 | 20050804 | 99875.0 | 0 | GILBERT, SAMUEL G | METHOD AND APPARATUS TO STIMULATE THE IMMUNE SYSTEM OF A BIOLOGICAL ENTITY | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,038,788 | ACCEPTED | Game apparatus and storage medium storing game program | A game apparatus includes two LCDs, a touch panel is provided in association with the one LCD. On the touch panel, an operation button corresponding to each player character is set. A setting of the operation button is changed according to an operation state (frequency of usage, operation coordinates position) by a player during playing the game. For example, a size of an operation effective area and a display position of the operation button are changed according to the frequency of usage. Furthermore, at least any one of the operation effective areas and the display position of the operation button is changed according to the operation coordinates position. | 1. A game apparatus utilizing a pointing device, comprising: a display portion for displaying at least more than one figures operated by a player; a figure position setting means for setting the figure at an arbitrary position of said display portion on the basis of an instruction from the player; an operation effective area setting means for setting a display area of said figure set by said figure position setting means as an operation effective area; an operation coordinates position detecting means for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining means for determining whether or not the operation coordinates position detected by said operation coordinates position detecting means is within said operation effective area, and a game processing means for executing a game process corresponding to the operation of said figure when it is determined to be within said operation effective area by said operation coordinates position determining means. 2. A game apparatus according to claim 1, further comprising a figure selecting means for selecting a figure to be displayed on said display portion out of a plurality of kinds of figures, wherein said figure position setting means sets the figure selected by said figure selecting means to an arbitrary position of said display portion. 3. A game apparatus according to claim 1, wherein said figure position setting means sets the display area of the figure rendered on said display portion according to the operation of said pointing device by said player as a figure position. 4. A game apparatus according to claim 3, further comprising a operation state detecting means for detecting an operation state of said figure; and a display position changing means for changing the display position of said figure on the basis of the operation state detected by said operation state detecting means. 5. A game apparatus according to claim 4, wherein said operation effective area setting means sets the display area of the figure changed by said display position changing means as an operation effective area. 6. A game apparatus according to claim 3, further comprising an operation state detecting means for detecting an operation state of said figure; and an operation effective area changing means for changing the operation effective area of said figure on the basis of the operation state detected by said operation state detecting means. 7. A game apparatus according to claim 1, further comprising a figure size changing means for changing a size of the figure displayed on said display portion; wherein said operation effective area setting means sets a display area of the figure changed by said figure size changing means as an operation effective area. 8. A game apparatus according to claim 7, wherein said figure size changing means changes the size of said figure according to an operation time of said pointing device by said player. 9. A game apparatus according to claim 1, further comprising an operation state detecting means for detecting an operation state of said figure; and a figure display area changing means for changing the display area of said figure on the basis of the operation state detected by said operation state detecting means; wherein said operation effective area setting means sets the display area of the figure changed by said figure display area changing means as an operation effective area. 10. A game apparatus according to claim 1, further comprising a game proceeding detecting means for detecting a game proceeding; and a figure display state changing means for changing a display state of the figure displayed on said display portion when it is detected that said game proceeding is shifted to a predetermined state by said game proceeding detecting means, wherein said operation effective area setting means sets the display area of the figure changed by said figure display state changing means as an operation effective area. 11. A game apparatus according to claim 10, further comprising a figure function setting means for setting a function of said figure; a figure function displaying means for displaying in association with said figure the function set by said figure function setting means; and a figure function changing means for changing the function set by said figure function setting means when said game proceeding is shifted to a predetermined state by said game proceeding detecting means; wherein said figure display state changing means changes in a displaying manner from the function displayed by said figure function displaying means to the function changed by said figure function changing means. 12. A game apparatus according to claim 10, wherein said figure display state changing means displays a new figure on said display portion when said game proceeding is shifted to a predetermined state by said game proceeding detecting means, and said operation effective area setting means sets a display area of said figure newly displayed as an operation effective area. 13. A game apparatus according to claim 10, further comprising a character selecting means for selecting an arbitrary character out of a plurality of kinds of characters; wherein said figure position setting means sets said figure at an arbitrary position of said display portion for each character selected by said character selecting means, said game proceeding detecting means detects whether or not the character selected by said character selecting means is changed, said figure display state detecting means, when the character is changed by said game proceeding detecting means, changes the position of said figure to the figure position set to the changed character, and said operation effective area setting means sets the display area of the figure changed by said figure display state changing means as an operation effective area. 14. A game apparatus according to claim 1, wherein said pointing device is a touch panel provided in association with said display portion, and said operation effective area setting means sets an area of said touch panel corresponding to the display area of said figure as an operation effective area. 15. A game apparatus utilizing a pointing device, comprising: a first display portion for displaying a game image; a second display portion arranged in proximity to said first display portion for displaying one or more figures to be operated by the player; a figure position setting means for setting said figure at an arbitrary position of said display portion on the basis of an instruction from the player; an operation effective area setting means for setting a display area of said figure set by said figure position setting means as an operation effective area; an operation coordinates position detecting means for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining means for determining whether or not the operation coordinates position detected by said operation coordinates position detecting means is within said operation effective area; and a game processing means for changing a game image displayed on at least said first display portion in response to the operation of said figure when it is determined to be within said operation effective area by said operation coordinates position determining means. 16. A game apparatus utilizing a pointing device, comprising: a display portion for displaying one or more figures to be operated by a player; a figure position setting means for setting said figure at a predetermined position of said display portion; an operation effective area setting means for setting a display area of said figure set by said figure position setting means as an operation effective area; an operation coordinates position detecting means for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining means for determining whether or not the operation coordinates position detected by said operation coordinates position detecting means is within said operation effective area; a game processing means for executing a game process corresponding to said figure when it is determined to be within said operation effective area by said operation coordinates position determining means; an operation state detecting means for detecting an operation state of said figure by the player; and an operation effective area changing means for changing at least the operation effective area of said figure on the basis of the operation state detected by said operation state detecting means. 17. A game apparatus according to claim 16, further comprising a figure display area changing means for changing the display area of said figure on the basis of the operation state detected by said operation state detecting means. 18. A game apparatus according to claim 16, further comprising a representative coordinates position extracting means for extracting a representative coordinates position out of a plurality of operation coordinates positions detected by said operation coordinates position detecting means; wherein said operation effective area changing means changes a position of the operation effective area of said figure on the basis of the representative coordinates position extracted by said representative coordinates position extracting means. 19. A game apparatus according to claim 18, wherein said representative coordinates position extracting means extracts an operation coordinates position being the greatest in number out of said plurality of operation coordinates positions as said representative coordinates position. 20. A game apparatus according to claim 16, wherein said operation state detecting means detects a difference between a central coordinates position of said figure and the operation coordinates position detected by said operation coordinates position detecting means, and said operation effective area changing means changes a position of the operation effective area of said figure on the basis of said difference. 21. A game apparatus according to claim 20, wherein said operation effective area changing means changes the positions of the operation effective areas as to all figures displayed on said display portion on the basis of said difference. 22. A game apparatus according to claim 20, further comprising an average value calculating means for calculating an average value of differences detected by said operation state detecting means every operation of said figure; wherein said operation effective area changing means changes the position of the operation effective area of said figure on the basis of the average value calculated by said average value calculating means. 23. A game apparatus according to claim 16, wherein said operation state detecting means detects the number of times of operations of said figure, and said operation effective area changing means changes a size of the operation effective area of said figure on the basis of said number of times of operations. 24. A game apparatus utilizing a pointing device, comprising a display portion for displaying at least one or more figures to be operated by a player; a figure position setting means for setting said figure at a predetermined position of said display portion; an operation effective area setting means for setting a display area of said figure set by said figure position setting means as an operation effective area; an operation coordinates position detecting means for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining means for determining whether or not the operation coordinates position detected by said operation coordinates position detecting means is within said operation effective area; a game processing means for executing a game process corresponding to said figure when it is determined to be within said operation effective area by said operation coordinates position determining means; an operation state detecting means for detecting an operation state of said figure by the player; and a figure display area changing means for changing the display area of said figure on the basis of the operation state detected by said operation state detecting means. 25. A game apparatus according to claim 24, further comprising an operation effective area changing means for changing the operation effective area of said figure in correspondence to the display area of the figure changed by said figure display area changing means. 26. A game apparatus according to claim 24, wherein said operation state detecting means detects a difference between a central coordinates position of said figure and the operation coordinates position detected by said operation coordinates position detecting means, and said figure display area changing means changes a position of the display area of said figure on the basis of said difference. 27. A game apparatus according to claim 24, wherein said operation state detecting means detects the number of times of operations of said figure, and said figure display area changing means changes a size of the display area of said figure on the basis of said number of times of operations. 28. A game apparatus according to claim 27, wherein said figure display area changing means reduces the display area of said figure when said number of times of operations is equal to or less than a first setting number of times, and enlarges the display area of said figure when said number of times of operations is equal to or more than a second setting number of times. 29. A game apparatus according to claim 27, wherein said figure display area changing means enlarges the display area of said figure when said number of times of operations is equal to or less than a first setting number of times, and reduces the display area of said figure when said number of times of operations is equal to or more than a second setting number of times. 30. A game apparatus according to claim 27, wherein said figure display area changing means erases the display area of said figure when said the number of times of operations is equal to or less than a third setting number of times. 31. A storage medium storing a game program to be executed by a game apparatus that utilizes a pointing device, and is provided with a display portion for displaying at least one or more figures to be operated by a player, said game program causes a processor of said game apparatus to execute a following steps of: a figure position setting step for setting said figure at an arbitrary position of said display portion on the basis of an instruction from the player; an operation effective area setting step for setting a display area of said figure set by said figure position setting step as an operation effective area; an operation coordinates position detecting step for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining step for determining whether or not the operation coordinates position detected by said operation coordinates position detecting step is within said operation effective area; and a game processing step for executing a game process corresponding to the operation of said figure when it is determined to be within said operation effective area by said operation coordinates position determining step. 32. A storage medium storing a game program according to claim 31, wherein said game program further executes a figure selecting step for selecting a figure to be displayed on said display portion out of a plurality of kinds of figures, and said figure position setting step sets the figure selected by said figure selecting step to an arbitrary position of said display portion. 33. A storage medium storing a game program according to claim 31, wherein said figure position setting step sets the display area of the figure rendered in said display portion according to an operating of said pointing device by said player as a figure position. 34. A storage medium storing a game program according to claim 31, wherein a figure size changing step for changing a size of the figure displayed on said display portion is further executed, and said operation effective area setting step sets a display area of the figure changed by said figure size changing step as an operation effective area. 35. A storage medium storing a game program according to claim 31, wherein said game program further executes a game proceeding detecting step for detecting a game proceeding, and a figure display state changing step for changing a display state of the figure displayed on said display portion when it is detected that said game proceeding is shifted to a predetermined state by said game proceeding detecting step, and said operation effective area setting step sets the display area of the figure changed by said figure display state changing step as an operation effective area. 36. A storage medium storing a game program to be executed by a game apparatus utilizing a pointing device that is provided with a first display portion for displaying a game image and a second display portion that is arranged in proximity to said first display portion and displays at least one or more figures to be operated by a player, said game program causes a processor of said game apparatus to execute a following steps of: a figure position setting step for setting said figure at an arbitrary position of said display portion on the basis of an instruction from the player; an operation effective area setting step for setting a display area of said figure set by said figure position setting step as an operation effective area; an operation coordinates position detecting step for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining step for determining whether or not the operation coordinates position detected by said operation coordinates position detecting step is within said operation effective area; and a game processing step for changing a game image displayed on at least said first display portion in response to an operation of said figure when it is determined to be within said operation effective area by said operation coordinates position determining step. 37. A storage medium storing a game program of a game apparatus utilizing a pointing device that is provided with a display portion for displaying one or more figures to be operated by a player, said game program causes a processor of said game apparatus to execute following steps of: a figure position setting step for setting said figure at a predetermined position of said display portion; an operation effective area setting step for setting a display area of said figure set by said figure position setting step as an operation effective area; an operation coordinates position detecting step for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining step for determining whether or not the operation coordinates position detected by said operation coordinates position detecting step is within said operation effective area; a game processing step for executing a game process corresponding to said figure when it is determined to be within said operation effective area by said operation coordinates position determining step; an operation state detecting step for detecting an operation state of said figure by the player; and an operation effective area changing step for changing at least, the operation effective area of said figure on the basis of the operation state detected by said operation state detecting step. 38. A storage medium storing a game program according to claim 37, wherein said game program further executes a figure display area changing step for changing the display area of said figure on the basis of the operation state detected by said operation state detecting step. 39. A storage medium storing a game program according to claim 37, wherein said game program further executes a representative coordinates position extracting step for extracting a representative coordinates position out of a plurality of operation coordinates positions detected by said operation coordinates position detecting step, and said operation effective area changing step for changing a position of the operation effective area of said figure on the basis of the representative coordinates position extracted by said representative coordinates position extracting step. 40. A storage medium storing a game program according to claim 39, wherein said representative coordinates position extracting step extracts an operation coordinates position being the greatest in number out of said plurality of operation coordinates positions as said representative coordinates position. 41. A storage medium storing a game program according to claim 37, wherein said operation state detecting step detects a difference between a central coordinates position of said figure and the operation coordinates position detected by said operation coordinates position detecting step, and said operation effective area changing step changes a position of the operation effective area of said figure on the basis of said difference. 42. A storage medium storing a game program according to claim 41, wherein said operation effective area changing step changes the positions of the operation effective areas as to all figures displayed on said display portion on the basis of said difference. 43. A storage medium storing a game program according to claim 41, wherein said game program executes an average value calculating step for calculating an average value of differences detected by said operation state detecting step every operation of said figure, and said operation effective area changing step changes a position of the operation effective area of said figure on the basis of the average value calculated by said average value calculating step. 44. A storage medium storing a game program according to claim 37, wherein said operation state detecting step detects the number of times of operations of said figure, and said operation effective area changing step changes a size of the operation effective area of said figure on the basis of said number of times of operations. 45. A storage medium storing a game program of a game apparatus utilizing a pointing device that is provided with a display portion for displaying one or more figures operated by a player, said game program causes a processor of said game apparatus to execute following steps of: a figure position setting step for setting said figure at a predetermined position of said display portion; an operation effective area setting step for setting a display area of said figure set by said figure position setting step as an operation effective area; an operation coordinates position detecting step for detecting an operation coordinates position on the basis of operation information detected by an operation of said pointing device; an operation coordinates position determining step for determining whether or not the operation coordinates position detected by said operation coordinates position detecting step is within said operation effective area; a game processing step for executing a game process corresponding to said figure when it is determined to be within said operation effective area by said operation coordinates position determining step; an operation state detecting step for detecting an operation state of said figure by the player; and a figure display area changing step for changing the display area of said figure on the basis of the operation state detected by said operation state detecting step. 46. A storage medium storing a game program according to claim 45, wherein said game program further executes an operation effective area changing step for changing the operation effective area of said figure in correspondence to the display area of the figure changed by said figure display area changing step. 47. A storage medium storing a game program according to claim 45, wherein said operation state detecting step detects a difference between a central coordinates position of said figure and the operation coordinates position detected by said operation coordinates position detecting step, and said figure display area changing step changes a position of the display area of said figure on the basis of said difference. 48. A storage medium storing a game program according to claim 45, wherein said operation state detecting step detects the number of times of operations of said figure, and said figure display area changing step changes a size of the display area of said figure on the basis of said number of times of operations. 49. A storage medium storing a game program according to claim 48, wherein said figure display area changing step reduces the display area of said figure when said number of times of operations is equal to or less than a first setting number of times, and enlarges the display area of said figure when said number of times of operations is equal to or more than a second setting number of times. 50. A storage medium storing a game program according to claim 48, wherein said figure display area changing step enlarges the display area of said figure when said number of times of operations is equal to or less than a first setting number of times, and reduces the display area of said figure when said number of times of operations is equal to or more than a second setting number of times. 51. A storage medium storing a game program according to claim 48, wherein said figure display area changing step erases the display area of said figure when said number of times of operation is equal to or less than a third setting number of times. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a game apparatus and a storage medium storing a game program. More specifically, the present invention relates to a game apparatus executing a game process by operating a pointing device provided in association with a display portion, and a storage medium storing a game program. 2. Description of the Prior Art An example of this kind of a conventional game apparatus is disclosed in a Japanese Patent Laying-open No.1994-285257 [A63F 9/22, A63F 5/04] laid-open on Oct. 11, 1994. An electronic composite game apparatus of this prior art can be executed by selecting any one of a plurality of kinds of games, and according to the kind of the selected game, a switch displayed on a display operation plate provided with a touch panel is changed. Furthermore, only a switch required to be displayed in correspondence with progress of the selected game is sequentially generated on the display operation plate. Another example of this kind of a conventional game apparatus is disclosed in a Japanese Patent Laying-open No. 1994-285259 [A63F 9/22] laid-open on Oct. 11, 1994. The liquid crystal controller of the other prior art is provided with a touch panel and a liquid crystal monitor on the controller main body, and is connected to a game machine main body to display operation information to be transmitted from the game machine main body on the liquid crystal monitor. The operation information is stored in a game cartridge loaded into the game machine main body, and therefore, it is possible to change the operation information according to a kind of the game similarly to the above-described prior art. However, in the above-described both prior arts, the switch (operation information) to be displayed on liquid crystal screen depending on the kind or in correspondence with the game is merely changed in number and function, and an operation effective area and a display area of the switch are not changed on the basis of an operation state of the displayed switch. For example, the game controller is generally made for a right-handed player, and therefore, it is difficult to operate for a left-handed player. Furthermore, a position, a size, etc. of the switch that is operable for the player is different between respective players. Furthermore, it is impossible to set and modify the switch according to a way (habit) of operation, frequency of operation by the player. SUMMARY OF THE INVENTION Therefore, it is a primary object of the present invention to provide a novel game apparatus and storage medium storing a game program. Another object of the present invention is to provide a game apparatus and a storage medium storing a game program that allows a player to freely display and set an operation figure at an arbitrary position of a display portion. The other object of the present invention is to provide a game apparatus and a storage medium storing a game program capable of changing an operation effective area according to an operation manner of the operation figure by the player. A further object of the present invention is to provide a game apparatus and a storage medium storing a game program capable of changing a display area of the operation figure according to an operation manner of the operation figure by the player. A game apparatus utilizing a pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, and a game processing means. The display portion displays one or more figures to be operated by a player. The figure position setting means sets a figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting means sets an area on the touch panel in correspondence to the display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. Then, the game processing means executes a game process corresponding to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. More specifically, the game apparatus (10: a reference numeral corresponding in the “preferred embodiment” described later and so forth) is provided with the display portion (14). The display portion (14) displays one or more figures to be operated by the player. For example, the pointing device (22) is provided in association with the display portion (14). The figure position setting means (42, S37, S329) sets the figure at an arbitrary position of the display portion (14) on the basis of the instruction from the player. The operation effective area setting means (42, S41, S331) sets the display area of the figure set by the figure position setting means (42, S37, S329) as the operation effective area. The operation coordinates position detecting means (42, S153) detects the operation coordinates position the on the basis of the operation information detected by the operation of the pointing device (22). The operation coordinates position determining means (42, S155) determines whether or not the operation coordinates position detected by the operation coordinates position detecting means (42, S153) is within the operation effective area. That is, it is determined whether or not the set figure is operated. The game processing means (42, S157) executes the game process corresponding to the operation of the figure to which the operation effective area is set when it is determined to be within the operation effective area by the operation coordinates position determining means (42, S155). According to the present invention, it is possible to freely set the figure at an arbitrary position of the screen, and it is possible to set the figure at a position suitable for operation for each player, capable of improving operability. In one aspect of this invention, a figure selecting means for selecting a figure to be displayed on the display portion out of a plurality of kinds of figures is further provided, and the figure position setting means sets the figure selected by the figure selecting means at an arbitrary position of the display portion. More specifically, the game apparatus (10) is further provided with the figure selecting means (42, S21, S23). The figure selecting means (42) selects the figure to be displayed on the display portion (14) out of the plurality of kinds of figures. The figure position setting means (42, S37, S329) sets the figure selected by the figure selecting means (42, S21, S23) at the arbitrary position of the display portion. Accordingly, a figure to suit the needs or preferences of the player out of the various kinds of figures can be selected. In one embodiment of this invention, the figure position setting means sets the display area of the figure rendered on the display portion according to the operation of the pointing device by the player as a figure position. More specifically, the figure position setting means (42, S37, S329) sets the display area of the figure rendered on the display portion (14) according to the operation of the pointing device (22) by the player as the figure position. For example, the player can freely render the figure. At this time, a position of the figure is set, and a shape and a size thereof are also set. Thus, the player can freely render the figure, capable of improving a savor of the game. In one aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and a display position changing means for changing the display position of the figure on the basis of the operation state detected by the operation state detecting means are further provided. More specifically, the game apparatus further comprises the operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′) and the display position changing means (42, S235, S235′, S235″, S235a, S239). The operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′) detects the operation state of the figure, and the display position changing means (42, S235, S235′, S235″, S235a, S239) changes the display position of the figure on the basis of the operation state detected by the operation state detecting means. Accordingly, by changing the display position of the figure according to a habit of operation, etc. of the player, it is possible to guide an operation position of the player so as to be coincident with the center of the operation effective area. In one embodiment of this invention, the operation effective area setting means sets the display area of the figure changed by the display position changing means as an operation effective area. More specifically, the operation effective area setting means (42, S41, S331) sets the changed display area of the figure as an operation effective area. That is, the position of the operation effective area is also changed. Thus, it is possible to easily inform the player that the position of the operation effective area is changed. In another aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and an operation effective area changing means for changing the operation effective area of the figure on the basis of the operation state are further provided. More specifically, the game apparatus comprises the operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′) and the operation effective area changing means (42, S233, S233′, S233″, S237). The operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′) detects the operation state of the figure, the operation effective area changing means (42, S233, S233′, S233″, S237) changes the operation effective area of the figure according to the detected operation state. That is, the display state by the player is reflected on the operation effective area. Accordingly, the position of the operation effective area can be changed according to an operation pattern, habit, etc. by the player, capable of improving operability. In the other aspect of this invention, a figure size changing means for changing a size of the figure displayed on the display portion is further provided, and the operation effective area setting means sets a display area of the figure changed by the figure size changing means as an operation effective area. More specifically, the figure size changing means (42, S39, S73, S95) changes the size of the figure displayed on the display portion (14). The operation effective area setting means (42, S41, S331) sets the display area of the figure changed by the figure size changing means (42, S39, S73, S95) as the operation effective area. Thus, it is freely change the size of the displayed figure. For example, the figure being high frequency of usage is displayed in an enlarged manner, and the figure being low frequency of usage is displayed in a reduced manner, and this makes it easy to operate. In one embodiment of this invention, the figure size changing means changes the size of the figure according to an operation time of the pointing device by the player. More specifically, the figure size changing means (42, S39, S95) changes the size of the figure according to the operation time of the pointing device (22) by the player. For example, the longer the operation time is, the larger the figure is rendered, or the figure is gradually rendered large for each unit of time. Thus, the size of the displayed figure is changed according to the operation time, and therefore, it is easy to operate. In another aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and a figure display area changing means for changing the display area of the figure on the basis of the operation state detected by the operation state detecting means are further provided, and the operation effective area setting means sets the display area of the figure changed by the figure display area changing means as an operation effective area. More specifically, the game apparatus (10) further comprises the operation state detecting means (42, S159, S185, S191) and the display area changing means (42, S187, S193). The operation state detecting means (42, S159, S185, S191) detects the operation state of the figure, and the display area changing means (42, S187, S193) changes the display area of the figure on the basis of the detected operation state. Here, the operation effective area setting means (42, S89, S195) sets the changed display area as the operation effective area. Thus, the display area of the figure (size) is modified according to the operation state of the displayed figure, capable of changing the display of the figure depending on the frequency of usage of the figure. In the other aspect of this invention, a game proceeding detecting means for detecting a game proceeding and a figure display state changing means for changing a display state of the figure displayed on the display portion when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means are further provided, and the operation effective area setting means sets the display area of the figure changed by the figure display state changing means as an operation effective area. More specifically, the game proceeding detecting means (42, S161, S167, S197) detects the game proceeding. The figure display state changing means (42, S145, S147, S163, S165, S169) changes the display state of the figure displayed on the display portion when it is detected that the game proceeding is shifted to the predetermined state (“YES” in the steps S161, S167, S197). Accordingly, the operation effective area setting means (42, S171) sets the display area of the figure changed by the figure display state changing means as the operation effective area. Thus, it is possible to change the display state of the figure according to the game proceeding. In another aspect of this invention, a figure function setting means for setting a function of the figure, a figure function displaying means for displaying the function set by the figure function setting means in association with the figure, and a figure function changing means for changing the function set by the figure function setting means when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means are further provided, and the figure display state changing means changes in a displaying manner from the function displayed by the figure function displaying means to the function changed by the figure function changing means. More specifically, the figure function setting means (42, S43, S45, S47) sets the function of the figure. The figure function displaying means (42, S147) displays in association with the figure the function set by the figure function setting means. The figure function changing means (42, S163) changes the function set to the figure when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means (“YES” in the step S161). The figure display state changing means (42, S163, S165) changes in a displaying manner from the function of the figure to the modified function. Thus, it is possible to change the function of the figure according to the game proceeding, capable of displaying the figure with the function required for the game state at that time. In one embodiment of this invention, the figure display state changing means displays a new figure on the display portion when the game proceeding is shifted to a predetermined state by the game proceeding detecting means, and the operation effective area setting means sets a display area of the figure newly displayed as an operation effective area. More specifically, when it is detected that the game proceeding is shifted to the predetermined state (“YES” in the S167), the figure display state changing means (42, S169) displays a new figure on the display portion (14). Accordingly, the operation effective area setting means (42, S171) sets the display area of the figure newly displayed as the operation effective area. Thus, it is possible to display a new figure in correspondence with the game proceeding, capable of increasing figures in correspondence with the game proceeding. In another aspect of this invention, a character selecting means for selecting an arbitrary character out of a plurality of kinds of characters is further provided, and the figure position setting means sets the figure at an arbitrary position of the display portion for each character selected by the character selecting means, and the game proceeding detecting means detects whether or not the character selected by the character selecting means is changed, the figure display state detecting means, when the character is changed by the game proceeding detecting means, changes the position of the figure to the figure position set to the changed character, and the operation effective area setting means sets the display area of the figure changed by the figure display state changing means as an operation effective area. More specifically, the character selecting means (42, S143) selects the arbitrary character out of the plurality of kinds of characters. The figure setting means (42, S145, S147) sets the figure at an arbitrary position of the display portion (14) for each character, the game proceeding detecting means (42, S197) detects whether or not the character selected by the character selecting means (42, S143) is changed. The figure display state detecting means (42, S145, S147), when the character is changed, changes the position of the figure to the figure position set to the changed character. Then, the operation effective area setting means (42, S145) sets the changed display area of the figure as an operation effective area. Accordingly, it is possible to set the display position of the figure for each plurality of kinds of characters, and when the character is modified, the figure can be changed to the display position set to the changed character, capable of setting the figure to an operable position for each character. In one embodiment of this invention, a pointing device is a touch panel provided in association with the display portion, and the operation effective area setting means sets an area of the touch panel corresponding to the display area of the figure as an operation effective area. More specifically, the pointing device is the touch panel (22) provided in association with the display portion (14). The operation effective area setting means (42, S41, S331) sets the area of the touch panel (22) corresponding to the display area of the figure as the operation effective area. Thus, the touch panel is utilized as a pointing device, capable of performing an intuitive operation. A game apparatus utilizing another pointing device according to this invention comprises a first display portion, a second display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, and a game processing means. The first display portion displays. a game image. The second display portion is arranged in proximity to the first display portion, and displays one or more figures to be operated by the player. The figure position setting means sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means changes a game image displayed on at least the first display portion in response to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The another game apparatus is approximately the same as the above-described game apparatus of this invention, and the game image is displayed on the first display portion (12), and in proximity thereto, the image to be operated by the player is displayed on the second display portion (14). In the other invention also, similarly to the above-described invention, it is possible to freely set the figure at an arbitrary position on the screen, capable of setting the figure at an operable position for each player. That is, it is possible to improve operability. A game apparatus utilizing the other pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, a game processing means, an operation state detecting means, and an operation effective area changing means. The display portion displays at least one or more figures. The figure position setting means sets the figure at a predetermined position of the display portion. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The operation state detecting means detects an operation state of the figure by the player. The operation effective area changing means changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting means. More specifically, the game apparatus (10) is provided with the display portion (14) for displaying one or more figures to be operated by the player. For example, the pointing device (22) is provided in association with the display portion (14). The figure position setting means (42, S37) sets the figure at the predetermined position of the display portion. The operation effective area setting means (42, S41) sets the display area of the figure set by the figure position setting means as the operation effective area. The operation coordinates position detecting means (42, S153) detects the operation coordinates position on the basis of the operation information detected by the operation of the pointing device (22). The operation coordinates position determining means (42, S155) determines whether or not the operation coordinates position detected by the operation coordinates position detecting means (42, S153) is within the operation effective area. The game processing means (42, S157) executes the game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means (42, S155). That is, the game process according to the function (command) set to the button is executed. The operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′) detects the operation state of the figure by the player. Then, the operation effective area changing means (42, S189, S195, S233, S233′, S233″, S237, S237′) changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting means(42, S159, S185, S191, S221, S221′, S229, S229′). According to the present invention, the operation effective area of the figure can be modified according to the operation state of the displayed figure, and therefore, the position of the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player. Thus, it is possible to improve operability. In one aspect of this invention, a figure display area changing means for changing the display area of the figure on the basis of the operation state detected by the operation state detecting means is further provided. More specifically, the figure display area changing means (42, S187, S193, S235, S235′, S235″, S239, S239′) changes the display area of the figure on the basis of the operation state detected by the operation state detecting means (42, S159, S185, S191, S221, S221′, S229, S229′). That is, the display area of the figure is also changed according to the operation state by the payer, and thus, it is possible to easily inform the player that the position of the operation effective area is changed. In another aspect of this invention, a representative coordinates position extracting means for extracting a representative coordinates position out of a plurality of operation coordinates positions detected by the operation coordinates position detecting means is further provided. The operation effective area changing means changes a position of the operation effective area of the figure on the basis of the representative coordinates position extracted by the representative coordinates position extracting means. More specifically, the representative coordinates position extracting means (42, S229′) extracts the representative coordinates position out of the plurality of operation coordinates positions detected by the operation coordinates position detecting means (42, S221′). The operation effective area changing means (42, S233″, S237) changes the position of the operation effective area of the figure on the basis of the representative coordinates position extracted by the representative coordinates position extracting means (42, S229′). Thus, the position of the operation effective area of the figure is changed to the representative coordinates position according to the operation state of the player, and therefore, the operation effective area can be corrected to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In one embodiment of this invention, the representative coordinates position extracting means extracts an operation coordinates position being the greatest in number out of the plurality of operation coordinates positions as the representative coordinates position. More specifically, the representative coordinates position extracting means (42, S229′) extracts the operation coordinates position being the greatest in number out of the plurality of operation coordinates positions, that is, the operation coordinates position being the highest in frequency of operation as the representative coordinates position. It is noted that an average value of a plurality of operation coordinates positions is calculated, and the operation coordinates position indicated by the calculated average value may be extracted as the representative coordinates position. Thus, the operation effective area is changed to the operation coordinates position being the highest in frequency of usage, and therefore, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player. In another aspect of this invention, the operation state detecting means detects the difference between a central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means, and the operation effective area changing means changes a position of the operation effective area of the figure on the basis of the difference. More specifically, the operation state detecting means (42, S159, S185, S191, S221, S229) detects the difference between the central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means (42, S153), and the operation effective area changing means (42, S189, S195, S233, S233′, S237, S237′) changes the position of the operation effective area of the figure on the basis of the difference. That is, the position of the operation effective area of the figure is changed on the basis of the difference between the central position of the figure and the operation coordinates position detected by the operation of the player, and therefore, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In one embodiment of this invention, the operation effective area changing means changes the positions of the operation effective areas as to all figures displayed on the display portion on the basis of the difference. More specifically, the operation effective area changing means (42, S189, S195, S233, S237) changes the positions of the operation effective areas as to all the figures displayed on the display portion on the basis of the difference. Thus, the positions of the operation effective areas of all the figures are changed on the basis of the difference between the central position of the figure and the operation coordinates position detected by the operation of the player, and therefore, it is possible to reduce a processing load for changing the position of the operation effective area. In another embodiment of this invention, an average value calculating means for calculating an average value of differences detected by the operation state detecting means every operation of the figure is further provided, and the operation effective area changing means changes the position of the operation effective area of the figure on the basis of the average value calculated by the average value calculating means. More specifically, the average value calculating means (42, S229) calculates the average value of the differences detected by the operation state detecting means (42, S221) every operation of the figure. The operation effective area changing means (42, S189, S195, S233, S237) changes the position of the operation effective area of the figure on the basis of the average value calculated by the average value calculating means (42, S229). That is, the position of the operation effective area of the figure can be changed on the basis of the average value of the differences detected by the central position of the figure and a plurality of number of times of operations by the player, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In the other aspect of this invention, the operation state detecting means detects the number of times of operations of the figure, and the operation effective area changing means changes a size of the operation effective area of the figure on the basis of the number of times of operations. More specifically, the operation state detecting means (42, S159) detects the number of times of operations of the figure. The operation effective area changing means (42, S189, S195) changes the size of the operation effective area of the figure on the basis of the number of times of operations. Thus, the operation effective area of the figure can be changed to an adequate size according to the number of times of operations, capable of improving operability. The game apparatus utilizing another pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, a game processing means, an operation state detecting means, and a figure display area changing means. The display portion displays one or more figures to be operated by the player. The figure position setting means sets the figure at a predetermined position of the display portion. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The operation state detecting means detects an operation state of the figure by the player. Then, the figure display area changing means changes the display area of the figure on the basis of the operation state detected by the operation state detecting means. In the other game apparatus, the display area of the figure is modified accord to the display state of the figure dissimilar to the above-described invention. According to this invention, the display area of the figure is modified according to an operation pattern, habit, frequency etc. of the figure by the player, and this leads the player to surely operate the position within the operation effective area, capable of improving operability. In one aspect of this invention, the figure display area changing means for changing the operation effective area of the figure in correspondence to the display area of the figure changed by the figure display area changing means is further provided. More specifically, the operation effective area changing means (42, S189, S195, S233, S237) modifies the operation effective area of the figure changed by the figure display area changing means (42, S187, S193, S235, S235′, S235″, S239′, S239″). That is, the operation effective area of the figure is modified according to an operation pattern, habit, frequency etc. of the figure by the player, capable of improving operability. Also, it is possible to inform the player that the operation effective area of the figure is modified. In one embodiment of this invention, the operation state detecting means detects a difference between a central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means, and the figure display area changing means changes a position of the display area of the figure on the basis of the difference. In this invention also, similarly to the above-described invention, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In another embodiment of this invention, the operation state detecting means detects the number of times of operations of the figure, and the figure display area changing means changes a size of the display area of the figure on the basis of the number of times of operations. In this invention also, similarly to the above-described invention, the operation effective area of the figure can be changed to an adequate size according to the number of times of operations, capable of improving operability. In the other embodiment of this invention, the figure display area changing means reduces the display area of the figure when the number of times of operations is equal to or less than a first setting number of times, and enlarges the display area of the figure when the number of times of operations is equal to or more than a second setting number of times. More specifically, the figure display area changing means (42, S187, S193) reduces the display area of the figure when the number of times of operations is equal to or less than the first setting number of times (“YES” in the S185), and enlarges the display area of the figure when the number of times of operations is equal to or more than the second setting number of times (“YES” in the S191). That is, the figure being a low frequency of usage is displayed in a reduced manner, and the figure being a high frequency of usage is displayed in an enlarged manner, and therefore, the figure not frequently utilized is displayed so as to makes it difficult to operate, and the figure frequently operated is displayed so as to make it easy to operate. In a further embodiment of this invention, the figure display area changing means enlarges the display area of the figure when the number of times of operations is equal to or less than a first setting number of times, and reduces the display area of the figure when the number of times of operations is equal to or more than a second setting number of times. More specifically, contrary to the above-described other embodiment, when the number of times of operations of the figure is equal to or less than the first setting number of times, the figure is displayed in an enlarged manner, and when the number of times of operations is equal to or more than the second setting number of times, the display area of the figure is reduced. That is, the figure being a low frequency of usage is displayed in an enlarged manner, and the figure being a high frequency of usage is displayed in a reduced manner, and therefore, a difficulty level of the game operation can be increased, capable of preventing reduction in an interest to the game play. In another embodiment of this invention, the figure display area changing means erases the display area of the figure when the number of times of operations is equal to or less than a third setting number of times. More specifically, the display area of the figure being a low frequency of usage, that is, having the number of times of operations being equal to or less than the third setting number of times is erased. That is, the figure being a low frequency of usage is erased, and therefore, it is possible to make it impossible to use the figure not frequently utilized. In a storage medium storing a game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus comprises a display portion for displaying one or more figures to be operated by the player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, and a game processing step. The figure position setting step sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. Then, the game processing step executes a game process corresponding to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. In the storage medium storing the game program of this invention, similalry to the above-described invention of the game apparatus, it is possible to freely set the figure at an arbitrary position of the screen, and therefore it is possible to set the figure at an operable position for each player. In a storage medium storing another game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a first display portion for displaying a game image and a second display portion arranged in proximity to the first display portion for displaying at least one or more figures to be operated by a player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, and a game processing step. The figure position setting step sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. Then, the game processing step changes a game image displayed on at least the first display portion in response to an operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. In the storage medium of this invention also, similarly to the above-described invention of the game apparatus, it is possible to freely set the figure at an arbitrary position of the screen, and therefore it is possible to set the figure at an operable position for each player. That is, operability is improved. In a storage medium storing the other game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a display portion for displaying at least one or more figures. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, a game processing step, an operation state detecting step, and an operation effective area changing step. The figure position setting step sets the figure at a predetermined position of the display portion. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. The game processing step executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. The operation state detecting step detects an operation state of the figure by the player. Then, the operation effective area changing step changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting step. In the storage medium of this invention also, similalry to the above-described invention of the game apparatus, the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player, capable of improving operability. In a storage medium storing another game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a display portion for displaying one or more figures to be operated by the player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, a game processing step, an operation state detecting step, and a figure display area changing step. The figure position setting step sets the figure at a predetermined position of the display portion. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. The game processing step executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. The operation state detecting step detects an operation state of the figure by the player. The figure display area changing step changes the display area of the figure on the basis of the operation state detected by the operation state detecting step. In the storage medium according to this invention, similalry to the above-described invention of the game apparatus, the position of the display area and the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player, capable of improving operability. Also, it is possible to easily inform the player that the operation effective area of the figure is modified. The above described objects and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustrative view showing one example of a game apparatus in a first embodiment of this invention; FIG. 2 is a block diagram showing an electric configuration of the game apparatus shown in FIG. 1; FIG. 3 is an illustrative view showing a memory map of a RAM (working memory) of the game apparatus shown in FIG. 2; FIG. 4 is a flowchart showing an entire process of a CPU core shown in FIG. 2; FIG. 5 is a flowchart showing one part of a button setting process to a touch panel by the CPU core shown in FIG. 2; FIG. 6 is a flowchart showing another part of the button setting process to the touch panel by the CPU core shown in FIG. 2; FIG. 7 is a flowchart showing a button figure size changing process (1) by the CPU core shown in FIG. 2; FIG. 8 is a flowchart showing a button figure size changing process (2) by the CPU core shown in FIG. 2; FIG. 9 is an illustrative view showing one example of a button figure selecting screen displayed on a second LCD of the game apparatus shown in FIG. 1; FIG. 10 is an illustrative view showing one example of a button arrangement position pointing screen displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 11 is an illustrative view showing one example of a button figure size change selecting screen displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 12 is an illustrative view showing one example of a button figure size changing screen displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 13 is an illustrative view showing another example of the button figure size changing screen displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 14 is an illustrative view showing one example of a button function selecting screen displayed on the second LCD of the game apparatus shown in FIG. 1;. FIG. 15 is an illustrative view showing one example of a next button setting selecting screen displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 16 is an illustrative view showing another example of the button figure selecting screen to be displayed on the second LCD of the game apparatus shown in FIG. 1; FIG. 17 is a flowchart showing a part of a game process on the basis of a touch panel by the CPU core shown in FIG. 2; FIG. 18 is a flowchart showing another part of the game process on the basis of the touch panel by the CPU core shown in FIG. 2; FIG. 19 is a flowchart showing the other part of the game process on the basis of the touch panel by the CPU core shown in FIG. 2; FIG. 20 is an illustrative view showing one example of a game screen displayed on the first LCD and an operation panel screen displayed on the second LCD in FIG. 1; FIG. 21 is an illustrative view showing another example of the game screen displayed on the first LCD and the operation panel screen displayed on the second LCD in FIG. 1; FIG. 22 is an illustrative view showing one example of a battle screen displayed on the first LCD and the operation panel screen displayed on the second LCD in FIG. 1; FIG. 23 is an illustrative view showing another example of the battle screen displayed on the first LCD and the operation panel screen displayed on the second LCD in FIG. 1; FIG. 24 is an illustrative view showing the other example of the game screen displayed on the first LCD and the operation panel screen displayed on the second LCD in FIG. 1; FIG. 25 is an illustrative view showing a further example of the game screen displayed on the first LCD and the operation panel screen displayed on the second LCD in FIG. 1; FIG. 26 is a flowchart showing a part of the game process based on the touch panel by the CPU core in a second embodiment of this invention; FIG. 27 is a flowchart showing another part of the game process based on the touch panel by the CPU core in the second embodiment of this invention; FIG. 28 is a flowchart showing the other part of the game process based on the touch panel by the CPU core in the second embodiment of this invention; FIG. 29 is a flowchart showing a further part of the game process based on the touch panel by the CPU core in the second embodiment of this invention; FIG. 30 is a flowchart showing a part of an operation button position correcting process by the CPU core in the second embodiment; FIG. 31 is a flowchart showing another part of the operation button position correcting process by the CPU core in the second embodiment; FIG. 32 is an illustrative view for describing an upper set in the operation button position correcting process in the second embodiment and a method of changing an operation effective area and a display position of the operation button on the basis of the upper; FIG. 33 is an illustrative view showing one example a state in which the operation effective area and the display position of the operation button are corrected in the operation button position correcting process in the second embodiment; FIG. 34 is an illustrative view showing one example the game screen displaying a message informing that the operation button position is corrected in the operation button position correcting process in the second embodiment; FIG. 35 is a flowchart showing a part of the game process based on the touch panel operation by the CPU core in a third embodiment of this invention; FIG. 36 is a flowchart showing another part of the game process based on the touch panel operation by the CPU core in the third embodiment of this invention; FIG. 37 is a flowchart showing a part of the operation button position correcting process by the CPU core in a fourth embodiment of this invention; FIG. 38 is an illustrative view showing one example of a state in which the operation effective area is corrected by the operation button position correcting process in the fourth embodiment; FIG. 39 is a flowchart showing a part of the operation button position correcting process by the CPU core in a fifth embodiment of this invention; FIG. 40 is an illustrative view showing one example of a state in which an operation effective area and a display position of each operation button is corrected by the operation button position correcting process in the fifth embodiment; FIG. 41 is a flowchart showing a part of the operation button position correcting process by the CPU core in a sixth embodiment of this invention; FIG. 42 is a flowchart showing another part of the operation button position correcting process by the CPU core in the sixth embodiment of this invention; FIG. 43 is a flowchart showing a part of the operation button position correcting process by the CPU core in a seventh embodiment of this invention; FIG. 44 is an illustrative view showing one example of a state in which only the display position of each operation button is corrected by the operation button position correcting process in the seventh embodiment; FIG. 45 is an illustrative view showing a memory map of a RAM of a game apparatus in a eighth embodiment; FIG. 46 is a flowchart showing a part of a button setting process to the touch panel in the eighth embodiment; FIG. 47 is an illustrative view showing one example of a button rendering instructing screen displayed on the second LCD shown in FIG. 1; FIG. 48 is an illustrative view showing one example of a rendering failure screen displayed on the second LCD shown in FIG. 1; FIG. 49 is an illustrative view showing one example of a button function selecting screen displayed on the second LCD shown in FIG. 1; FIG. 50 is an illustrative view showing one example of a next button rendering selecting screen displayed on the second LCD shown in FIG. 1; and FIG. 51 is an illustrative view showing another example of the button rendering instructing screen displayed on the second LCD shown in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Referring to FIG. 1, a game apparatus 10 (hereinafter simply referred to as “game apparatus”) of one embodiment of this invention includes a first liquid crystal display (LCD) 12 and a second LCD 14. The LCD 12 and the LCD 14 are provided on a housing 16 so as to be arranged in a predetermined position. In this embodiment, the housing 16 consists of an upper housing 16a and a lower housing 16b, and the LCD 12 is provided on the upper housing 16a while the LCD 14 is provided on the lower housing 16b. Accordingly, the LCD 12 and the LCD 14 are closely arranged so as to be longitudinally (vertically) parallel with each other. It is noted that although an LCD is utilized as a display in this embodiment, an EL (Electronic Luminescence) display and a plasma display may be used in place of the LCD. As can be understood from FIG. 1, the upper housing 16a has a plane shape little larger than a plane shape of the LCD 12, and has an opening formed so as to expose a display surface of the LCD 12 from one main surface thereof. On the other hand, the lower housing 16b has a plane shape horizontally longer than the upper housing 16a, and has an opening formed so as to expose a display surface of the LCD 14 at an approximately center of the horizontal direction. Furthermore, the lower housing 16b is provided with a sound hole 18 and an operating switch 20 (20a, 20b, 20c, 20d, 20e, 20L and 20R). In addition, the upper housing 16a and the lower housing 16b are rotatably connected at a lower side (lower edge) of the upper housing 16a and a part of an upper side (upper edge) of the lower housing 16b. Accordingly, in a case of not playing a game, for example, if the upper housing 16a is rotatably folded such that the display surface of the LCD 12 and the display surface of the LCD 14 are face to face with each other, it is possible to prevent the display surface of the LCD 12 and the display surface of the LCD 14 from being damaged such as a flaw, etc. It is noted that the upper housing 16a and the lower housing 16b are not necessarily rotatably connected with each other, and may alternatively be provided integrally (fixedly) to form the housing 16. The operating switch 20 includes a direction instructing switch (cross switch) 20a, a start switch 20b, a select switch 20c, an action switch (A button) 20d, an action switch (B button) 20e, an action switch (L button) 20L, and an action switch (R button) 20R. The switches 20a, 20b and 20c are placed at the left of the LCD 14 on the one main surface of the lower housing 16b. Also, the switches 20d and 20e are placed at the right of the LCD 14 on the one main surface of the lower housing 16b. Furthermore, the switches 20L and 20R are placed at a part of an upper edge (top surface) of the lower housing 16b at a place except for a connected portion, and lie of each side of the connected portion with the upper housing 16a. The direction instructing switch 20a functions as a digital joystick, and is utilized for instructing a moving direction of a player character (or player object) to be operated by a player, instructing a moving direction of a cursor, and so forth by operating any one of four depression portions. The start switch 20b is formed by a push button, and is utilized for starting (restarting), suspending (pausing) a game, and so forth. The select switch 20c is formed by the push button, and utilized for a game mode selection, etc. The action switch 20d, that is, the A button is formed by the push button, and allows the player character to perform an arbitrary action, except for instructing the direction, such as hitting (punching), throwing, holding (obtaining), riding, jumping, etc. For example, in an action game, it is possible to apply an instruction of jumping, punching, moving arms, etc. In a role-playing game (RPG) and a simulation RPG, it is possible to apply an instruction of obtaining an item, selecting and determining arms or commands, etc. The action switch 20e, that is, the B button is formed by the push button, and is utilized for changing a game mode selected by the select switch 20c, canceling an action determined by the A button 20d, and so forth. The action switch (left depression button) 20L and the action switch (right depression button) 20R are formed by the push button, and the left depression button (L button) 20L and the right depression button (R button) 20R can perform the same operation as the A button 20d and the B button 20e, and also function as a subsidiary of the A button 20d and the B button 20e. Also, on a top surface of the LCD 14, a touch panel 22 is provided. As the touch panel 22, any one kind of a resistance film system, an optical system (infrared rays system) and an electrostatic capacitive coupling system, for example, can be utilized. In response to an operation by depressing, stroking (touching), and so forth with a stick 24, a pen (stylus pen), or a finger (hereinafter, referred to as “stick 24, etc.”) on a top surface of the touch panel 22, the touch panel 22 detects a coordinates position of the stick 24, etc. to output coordinates position data. It is noted that in this embodiment, a resolution of the display surface of the LCD 14 is 256 dots×192 dots, and a detection accuracy of a detection surface of the touch panel 22 is also rendered 256 dots×192 dots in correspondence to the resolution of the display surface (this is true for the LCD 12). However, detection accuracy of the detection surface of the touch panel 22 may be lower than the resolution of the display surface of the LCD 14, or higher than it. In this embodiment, a game screen is displayed on the LCD 12, and text information, an icon, etc. are displayed on the LCD 14. Accordingly, the player is able to, for example, select a command indicated by the texture information, the icon, etc. displayed on the display screen of the LCD 14, instruct a scrolling (gradual moving display) direction of the game screen (map) displayed on the LCD 12, and so forth by operating the touch panel 22 with the use of the stick 24, etc. Furthermore, depending on the kind of the game, the player is able to use the LCD 14 for another various input instructions, such as selecting or operating the icon displayed on the LCD 14, instructing a coordinates input, and so forth. Thus, the game apparatus 10 has the LCD 12 and the LCD 14 as a display portion of two screens, and the touch panel 22 is provided on an upper surface of any one of them (LCD 14 in this embodiment), and whereby, the game apparatus 10 has two screens (LCD 12, 14) and the operating portions (20, 22) of two systems. Furthermore, in this embodiment, the stick 24 can be inserted into a housing portion (housing slot) 26 provided in proximity to a side surface (right side surface) of the upper housing 16a, for example, and taken out therefrom as necessary. It is noted that in a case of preparing no stick 24, it is not necessary to provide the housing portion 26. Also, the game apparatus 10 includes a memory card (or game cartridge) 28, and the memory card 28 is detachable, and inserted into a loading slot 30 provided on a rear surface or a lower edge (bottom surface) of the lower housing 16b. Although omitted in FIG. 1, a connector 46 (see FIG. 2) is provided at a depth portion of the loading slot 30 for connecting a connector (not shown) provided at an end portion of the memory card 28 in the loading direction, and when the memory card 28 is loaded into the loading slot 30, the connectors are connected with each other, and therefore, the memory card 28 is accessible by a CPU core 42 (see FIG. 2) of the game apparatus 10. It is noted that although not illustrated in FIG. 1, a speaker 32 (see FIG. 2) is provided at a position corresponding to the sound hole 18 inside the lower housing 16b. Furthermore although omitted in FIG. 1, for example, a battery accommodating box is provided on a rear surface of the lower housing 16b, and a power switch, a volume switch, an external expansion connector, an earphone jack, etc. are provided on a bottom surface of the lower housing 16b. FIG. 2 is a block diagram showing an electric configuration of the game apparatus 10. Referring to FIG. 2, the game apparatus 10 includes an electronic circuit board 40, and on the electronic circuit board 40, a circuit component such as a CPU core 42, etc. is mounted. The CPU core 42 is connected to the connector 46 via a bus 44, and is connected with a RAM 48, a first graphics processing unit (GPU) 50, a second GPU 52, an input-output interface circuit (hereinafter, referred to as “I/F circuit”) 54, and an LCD controller 60. The connector 46 is detachably connected with the memory card 28 as described above. The memory card 28 includes a ROM 28a and a RAM 28b, and although illustration is omitted, the ROM 28a and the RAM 28b are connected with each other via a bus and also connected with a connector (not shown) to be connected with the connector 46. Accordingly, the CPU core 42 gains access to the ROM 28a and the RAM 28b. The ROM 28a stores in advance a game program for a game (virtual game) to be executed by the game apparatus 10, image data (character image, background image, item image, icon (button) image, message image, etc.), data of the sound (sound data) necessary for the game (music), etc. The RAM (backup RAM) 28b stores (saves) proceeding data and result data of the game. The RAM 48 is utilized as a buffer memory or a working memory. That is, the CPU core 42 loads the game program, the image data, the sound data, etc. stored in the ROM 28a of the memory card 28 into the RAM 48, and executes the loaded game program. The CPU core 42 executes a game process while storing in the RAM 48 data (game data and flag data) temporarily generated in correspondence with a progress of the game. It is noted that such the game program, the image data, the sound data, etc. are loaded from the ROM 28a entirely at a time, or partially and sequentially so as to be stored (loaded) into the RAM 48. Each of the GPU 50 and the GPU 52 forms a part of a rendering means, is constructed by, for example, a single chip ASIC, and receives a graphics command (construction command) from the CPU core 42 to generate game image data according to the graphics command. It is noted that the CPU core 42 applies to each of the GPU 50 and the GPU 52 an image generating program (included in the game program) necessary to generate game image data in addition to the graphics command. It is noted that each of the GPU 50 and the GPU 52 gains access to the RAM 48 to fetch data (image data) required for executing the construction command by the GPU 50 and the GPU 52. Furthermore, the GPU 50 is connected with a first video RAM (hereinafter, referred to as “VRAM”) 56, and the GPU 52 is connected with a second VRAM 58. The GPU 50 renders the created game image data in the VRAM 56, and the GPU 52 renders the created game image data in the VRAM 58. The VRAM 56 and the VRAM 58 are connected to the LCD controller 60. The LCD controller 60 includes a register 62, and the register 62 consists of, for example, one bit, and stores a value of “0” or “1” (data value) according to an instruction of the CPU core 42. The LCD controller 60 outputs the game image data rendered in the VRAM 56 to the LCD 12, and outputs the game image data rendered in the VRAM 58 to the LCD 14 in a case that the data value of the register 62 is “0”. Furthermore, the LCD controller 60 outputs the game image data rendered in the VRAM 56 to the LCD 14, and outputs the game image data rendered in the VRAM 58 to the LCD 12 in a case that the data value of the register 62 is “1”. The I/F circuit 54 is connected with the operating switch 20, the touch panel 22 and the speaker 32. Here, the operating switch 20 is the above-described switches 20a, 20b, 20c, 20d, 20e, 20L and 20R, and in response to an operation of the operating switch 20, a corresponding operation signal (operation data) is input to the CPU core 42 via the I/F circuit 54. Furthermore, the coordinates position data from the touch panel 22 is input to the CPU core 42 via the I/F circuit 54. In addition, the CPU core 42 reads-out the sound data necessary for the game such as a game music (BGM), a sound effect or voices of a game character (onomatopoeic sound), etc. from the RAM 48, and outputs it from the speaker 32 via the I/F circuit 54. For example, in the game apparatus 10, it is possible to play the game by use of the operating switch 20 provided on the housing 16 (housing 16b), and it is also possible to play the game by use of the operation button (operation panel) displayed on the LCD 14. In this embodiment, the operation button set on the operation panel 22, that is, the operation button displayed on the LCD 14 (touch panel screen) can arbitrarily be set by the player. That is, it is possible to arbitrarily set a figure, a position, a size, and a function (command) of the button as to the operation button displayed on the LCD 14. This is because that although in the game apparatus 10 (it is true for a general game apparatus), an arrangement of the operation button 20 is determined taking operability of a right-handed player, there is a problem of making it difficult to operate for a left-handed player. Furthermore, not all right-handed players feel ease of operation, and not all players feel ease of operation. Such the setting of the operation button can be performed for each character to be operated by the player (operation character), that is, the player character. The content of the setting is stored in the RAM 48, and during the game, a content of the setting corresponding to the player character is reads-out from the RAM 48 to display the operation button on the LCD 14. In addition, a display of the operation button is modified according to the change of the player character. Furthermore, in correspondence with the proceeding of the game, the size of the operation button is changed, the function of the operation button is changed, or a special operation button is displayed/non-displayed, and so forth. It is noted that although the operation button is arbitrarily set on the touch panel 22 in this embodiment, in a case of starting the game from the top, the operation button set in advance is displayed in the form of a predetermined figure in a predetermined size at a predetermined position. Thereafter, in correspondence with the progress of the game, the size of the operation button may be changed, the function of the operation button may be changed, or a special operation button may be displayed/non-displayed. Alternatively, the operation button set in advance is displayed in a predetermined figure in a predetermined size at a predetermined position, and before starting a main story of the game, the setting may be changed. FIG. 3 shows a memory map of the RAM 48. As shown in FIG. 3, the RAM 48 includes an operation button storing area 70 and another storing area 72. Although illustration is omitted for the sake of drawings, the game program, the image data, the sound data, etc. loaded from the ROM 28a and the game data (including a flag and a counter) generated inc correspondence with progress of the game are stored in the other storing area 72. The operation button storing area 70 includes an operation button storing area 80 of a first player character, an operation button storing area 82 of a second player character, etc. Here, the first player character and the second player character are player characters selected by the player, and not fixedly determined. In the operation button storing area 80 of the first player character, a setting A button storing area 800, a setting B button storing area 802, etc. are provided. Here, the “A button”, the “B button”, etc. are names applied as a matter of convenience in order to distinguish the operation button set by the player, and do not mean that they have functions the same as the above-described A button 20d, and B button 20e. It is noted that they may have the same function depending on the setting of the player. The setting A button storing area 800 stores attribute information as to the A button set by the player in correspondence to the first player character. More specifically, the setting A button storing area 800 stores as attribute information as to the A button figure data 800a, coordinates position data 800b, size data 800c, function data 800d, and operation effective area data 800e. For example, the figure data 800a is image (figure) data in the form of a circle prepared in advance as a default or a label indicative of a figure of the circle. The coordinates position data 800b is data of central coordinates (Xa, Ya) of the figure (circle). The size data 800c is data of a length from a center of the circle to an apex, that is, a radius (La). The function data 800d is data indicative of a command input of “talk (speak)” or a label indicative of the command. Here, although one function is set for simplicity, two or more functions may be set. This is because that in the action RPG, an input command (function) of the same operation button is different between when a player character moves on a map and when the player character fights with the enemy character in a fighting scene. Hereinafter, this is the same. Then, the operation effective area data 800e is a coordinates position data collection for determining whether or not an operation of the operation button (A button, here) is effective. These are the coordinates position data indicative of a position on the touch panel 22 in correspondence to the display area in a case of displaying operation button on the LCD 14, and correspond to respective dots within the display area. Accordingly, when the coordinates position data is fetched from the touch panel 22 during the game process based on the operation of the touch panel 22, it is determined whether or not the coordinates position data is coincident with the operation effective area data, and whereby, it is possible to easily determine whether or not the operation button is operated. Hereinafter, this is the same. It is noted that the operation effective area (of data) is not necessarily set, by determining whether or not the operation button is displayed at the coordinates position indicated by the coordinates position data fetched from the touch panel 22, whether or not the operation button is operated can also be determined. The setting B button storing area 802 stores the attribute information as to the B button set in correspondence with the first player character by the player. More specifically, the setting B button storing area 802, similarly to the setting A button storing area 800, stores figure data 802a, coordinates position data 802b, size data 802c, function data 802d and operation effective area data 802e. For example, the figure data 802a is image (figure) data in the form of a square prepared in advance as a default, or a flag indicative of the square figure. The coordinates position data 802b is central coordinates (Xb, Yb) data of the figure (square). The size data 802c is data of a length (Lb) from the center of the square to an apex. The function data 802d is data indicative of a command input of the “swing a sword”, or a label indicative of the command. Then, the operation effective area data 802e is a coordinates position data collection for determining whether or not an operation of the operation button (B button, here) is effective. In the operation button storing area 82 of the second player character, the setting A button storing area 820, etc. is provided. The setting A button storing area 820 stores the attribute information as to the A button set in correspondence to the second player character by the player. Here, the “A button” is a name applied by the player in order to distinguish the operation button set in correspondence to the second player character by the player as a matter of convenience, and this does not mean that they have functions the same as the above-described A button 20d, and B button 20e. Furthermore, this does not mean having the same figure, position, size, function and operation effective area as the A button, etc. set in correspondence to the first player character. It is noted that this may be settable so as to have a function the same as the A button 20d and the B button 20e, and can be set with a figure, etc. the same as the A button, etc. in correspondence to the first player character. The setting A button storing area 820 stores figure data 820a, coordinates position data 820b, function data 820c, and operation effective area data 820d. For example, the figure data 820a is image (figure) data in the form of a star prepared in advance as a default and a flag indicative of the figure of the star. The coordinates position data 820b is data of the central coordinates (Xc, Yc) of the figure (star). The size data 820c is data of a length (Lc) from the center of the star to an apex. The function data 820d is data indicative of a command input of “use a magic”, or a label indicative of the command. Then, the operation effective area data 820e is a coordinates position data collection indicative of whether or not an operation of the operation button (A button, here) is effective. Such the setting of the operation button and the attribute information can be performed before starting the main story of the game. During the game, the operating switch 20 or the operation button set on the touch panel 22 can be used. In addition, in the game process based on the operation of the touch panel 22, as described above, the attribute information of the set operation button is modified in correspondence to the progress of the game, or a special operation button is displayed (usable)/non-displayed (unusable). A detailed content is described by use of flowcharts shown in FIG. 4 and the succeeding, and display examples of the LCD 12 and the LCD 14. It is noted that the CPU core 42 shown in FIG. 2 processes according to the flowchart shown in FIG. 4 and the succeeding. FIG. 4 is the flowchart showing an entire process of the CPU core 42. When a main power supply of the game apparatus 10 is turned on, the CPU core 42 starts a process, and executes an initial setting in a step S1. For example, here, various flags are initialized (turned off), the VRAMs 56, 58 are initialized, and so forth. In a succeeding step S3, a player character is selected, and in a step S5, a button setting process (see FIG. 5 and FIG. 6) to the touch panel to be described later in detail is executed. It is noted that in the step S3, strictly speaking, the CPU core 42 displays a selection screen (not illustrated) of the player character to allow the player to select arbitrary (desired) player character. Then, in a step S7, it is determined whether or not another player character is selected. That is, a screen (not illustrated) for determining whether or not to select another player character is displayed to allow the player to select any one of them. If “YES” in the step S7, that is, if another player character is selected, the process returns to the step S3. On the other hand, if “NO” in the step S7, that is, if another player character is not selected, the process proceeds to a step S9. Thus, by executing such the processes in the steps S3 to S7, the player can select one or more player characters, and can execute a setting (S5) of the operation button with respect to the selected player character. In the step S9, it is determined whether or not the game according to an operation of the touch panel is executed. Here, a screen (not illustrated) for determining whether or not to execute the game according to the operation of the touch panel is displayed to allow the player to determine any one of them. If “YES” in the step S9, that is, if the game according to the operation of the touch panel is executed, a game process according to the operation of the touch panel (see FIG. 17 to FIG. 19) to be described later in detail is executed in a step S11, and then, the process proceeds to a step S15. On the other hand, if “NO” in the step S9, that is, if the game according to the operation of the touch panel is not executed, a normal game process based on a button operation (operating switch 20) is executed, and then, the process proceeds to the step S15. In the step S15, a game end process is executed to end the entire process. For example, in the step S15, in a case that a game over flag is turned on during the game process in the step S11 or S13, the game end process is executed. FIG. 5 and FIG. 6 show a flowchart showing the button setting process to the touch panel in the step S5 shown in FIG. 4. As shown in FIG. 5, when the button setting process is started, a button figure selecting screen 100 shown in FIG. 9 is displayed on the LCD 14 in a step S21. Referring to FIG. 9, the button figure selecting screen 100 is provided with a button figure icon displaying area 102 at an upper part of the screen, and message displaying area 104 at a lower part of the screen. In the button figure icon displaying area 102, button figures (designs) 102a, 102b, 102c and 102d prepared as a default are displayed. It is noted that these button figures are a simple example, or may be another figure. Alternatively, a multiplicity of button figures may be displayed. In the message displaying area 104, a message instructing a selection of the button figure as to the button (A button, here) first set is displayed. Accordingly, on the button figure selecting screen 100, a button figure as to the A button to be set can be selected, and at a time of selection, a touch (depression) on the LCD 14 (touch panel 22) with the stick 24, etc. is appropriate. Returning to FIG. 5, in a succeeding step S23, it is determined whether or not the button figure is selected. Here, a position (coordinates position) on the LCD 14 corresponding to the coordinates position indicated by the coordinates position data from the touch panel 22 is specified, and it is determined whether or not a button figure 102a, 102b, 102c or 102d displayed on the specified position is present. Furthermore, in a case that the button figure 102a, 102b, 102c or 102d displayed at the specified position is present, the button figure 102a, 102b, 102c or 102d is specified. It is noted that similalry to the operation button set by the player, an operation effective area corresponding to each of the button figures 102a to 102d is set on the touch panel 22, it is possible to determine whether or not the button figure is selected on the basis of the coordinates position data from the touch panel 22, and, if the button figure is selected, easily determine which is the selected button figure. If “NO” in the step S23, that is, if the button figure is not selected, it is determined to be canceled or not in a step S25. That is, it is determined whether or not a setting as to the A button is stopped. More specifically, it is determined whether or not the cancel button (B button 20e in this embodiment) is turned on. It is noted that the cancel button (icon) is displayed on the LCD 14 to be operable with the stick 24, etc. The same is true for the later description. If “NO” in the step S25, that is, if it is not canceled, it is determined that no button figure is selected, and then, the process returns to the step S21. However, if “YES” in the step S25, that is, if it is canceled, the process proceeds to a step S49 shown in FIG. 6. Alternatively, if “YES” in the step S23, that is, if the button figure is selected, the selected button figure is set in a step S27. Here, as shown in FIG. 3, the button figure data is written to the RAM 48 in correspondence to the player character selected in the step S3 shown in FIG. 4. In a succeeding step S29, the image data of the selected button figure is read from the RAM 48, and in a step S31, a button arrangement position pointing screen 110 shown in FIG. 10 is displayed on the LCD 14. Referring to FIG. 10, on the button arrangement position pointing screen 110, a message displaying area 104 is provided at the lower part of the screen. Furthermore, on the button arrangement position pointing screen 110, the selected button figure (button figure 102a, here) is displayed at the center of the screen. In the message displaying area 104, a message indicative of pointing the arrangement position as to the button (A button, here) to be set is displayed. Accordingly, the player can arbitrarily designate the arrangement position of the A button by the stick 24, etc. In a case that the arrangement position of the A button designated, it becomes possible to touch (depress) the LCD 14 (touch panel 22) in order to designate (click) a desired (arbitrary) arrangement position, and to stroke the LCD 14 (touch panel 22) in order to move (drag) the button figure 102a to a desired arrangement position. It is noted that the designated arrangement position is the central position of the button figure. Returning to FIG. 5, in a succeeding step S33, it is determined whether or not the button arrangement position is pointed. Here, it is determined whether or not the above-described designating operation of the arrangement position is present on the basis of the coordinates position data from the touch panel 22. If “NO” in the step S33, that is, if the button arrangement position is not pointed, it is determined whether or not to be canceled in a step S35. Here, if it is not canceled, “NO” is determined, and the process directly returns to the step S31 while if it is canceled, “YES” is determined, and the process directly proceeds to the step S49. On the other hand, if “YES” in the step S33, that is, if the button arrangement position is pointed, the button figure arrangement position is set to a pointed coordinates position in a step S37. That is, the coordinates position data is written to the RAM 48 in correspondence to the player character. In a following step S39, a size changing process of the button figure (see FIG. 7 and FIG. 8) is executed. In this embodiment, two ways of the size changing process of the button figure is present, and FIG. 7 shows a flowchart of a size changing process of the button figure (1), and FIG. 8 shows a flowchart of a size changing process of the button figure (2). It is noted that it is appropriate that any one of these processes is executed, and can be set in advance by a programmer or a developer of the game, or selected by the player on the menu screen. Referring to FIG. 7, when the button figure size changing process (1) is started, a button figure size change selecting screen 120 as shown in FIG. 11 is displayed on the LCD 14 in a step S61. The screen 120 is a screen for selecting whether or not the figure size of the button is changed. Referring to FIG. 11, on the button figure size change selecting screen 120, a message displaying area 104 is provided at the lower part of the screen. Furthermore, a button figure 102a of the A button is displayed at the left from the center of the screen. That is, the button figure 102a is displayed at the arrangement position pointed on the button arrangement position pointing screen 110 shown in FIG. 10. Furthermore, in the message displaying area 104, a message allowing the player to select whether or not to change the button size is displayed. As can be understood from FIG. 11, in this embodiment, “YES” and “NO” are displayed as the message so as to be selected by the stick 24, etc., but this may be selected by use of the operating switch 20. For example, when the A button 20d is turned on (operated), it is determined the size of the button figure is changed while when the B button 20e is turned on, it is determined the size of the button figure is not changed. Returning to FIG. 7, in a succeeding step S63, it is determined whether or not the button size is to be changed. That is, it is determined whether or not “YES” is selected. If “NO” in the step S63, that is, if “NO” is selected, it is determined the size of the button figure is not changed, and then, the button figure size changing process (1) is directly returned. On the other hand, if “YES” in the step S63, that is, if “YES” is selected, it is determined that the size of the button figure is changed, and in a step S65, a figure size changing screen 130 as shown in FIG. 12 is displayed on the LCD 14. Referring to FIG. 12, as to the figure size changing screen 130, a message displaying area 104 is provided at the lower part of the screen. Furthermore, on the figure size changing screen 130, the button figure 102a as to the A button is displayed at the left from the center of the screen (displayed by dotted lines in FIG. 12), and guide lines 132 for changing the size is displayed around it. In addition, in the message displaying area 104, a message prompting the player to determine the size of the button figure 102a is displayed. For example, the player strokes the LCD 14 (touch panel 22) by moving any one of the guide lines 132 such that the button figure becomes a size desired to be changed. Thereupon, corresponding thereto, the size of the button figure 102a is changed. In this embodiment, in order to display a text (name and function of the button) in the button figure, a size of the button figure to be displayed as a default is rendered minimum, and the size of the button figure 102a can be changed (reduced or enlarged) within the minimum value. It is noted that a maximum value of the size of the button figure may be set in advance as described later. It is noted that although the stick 24, etc. strokes the LCD 14 so as to move the guide lines 132 in this embodiment, the button figure may be enlarged depending on the number of times of designating (touching or depressing) the button figure (102a). In such a case, the button figure can be enlarged such that a distance from the center of the button figure to the apex (radius in the button figure 102a) is extended by a predetermined value (predetermined length) successively or every predetermined number of times. Returning to FIG. 7, in a following step S67, it is determined whether or not the operation is started. That is, it is determined whether or not an operation of the stick 24, etc. is started so as to move the guide lines 132. If “NO” in the step S67, that is, if the operation is not started, it is determined whether or not to be canceled in a step S69. Here, if it is not canceled, “NO” is determined, and the process directly returns to the step S65 while if it is canceled, “YES” is determined, and the button figure size changing process (1) is directly returned. On the other hand, if “YES” in the step S67, that is, if the operation is started, it is determined whether or not to be the maximum value in a step S71. That is, it is determined whether or not the size of the button figure (102a) becomes the maximum value set in advance. It is noted that the maximum value is arbitrarily set in advance with respect to each of the button figures 102a, 102b, 102c, 102d on the basis of the size, etc. of the LCD 14 by the programmer or the developer of the game. If “YES” in the step S71, that is, if it is the maximum value, the button figure size changing process (1) is returned. In this case, the size of the button figure 102a is set to the maximum value, and the size data is written to the RAM 48 in correspondence to the player character. On the other hand, if “NO” in the step S71, that is, if it is not the maximum value, the size of the button figure is changed on the basis of the operation by the player in a step S73. Here, the button figure is displayed in an enlarged or reduced manner such that a distance (radius in the button figure 102a) from the center of the button figure to the apex is extended by a moving length of the guide lines 132. It is noted that the button figure changed in size has similar figure to the button figure before change. Then, in a step S75, it is determined whether or not the operation is completed. Here, it is determined whether or not the stick 24, etc. is released from the LCD 14 (touch panel 22), that is, whether or not the coordinates position data is not input from the touch panel 22. If “NO” in the step S75, that is, if the operation is not completed, the process directly returns to the step S71. On the other hand, if “YES” in the step S75, that is, if the operation is completed, the button figure size changing process (1) is returned. In this case, the size of the button figure 102a is set to the size directed (designated) by the player, and the size data is written to the RAM 48 in correspondence to the player character. It is noted that if “NO” in the step S63, or if “YES” in the step S69, the size of the button figure 102a is set to the default value, and the size data is written to the RAM 48 in correspondence to the player character. FIG. 8 shows a flowchart showing the button figure size changing process (2). Here, the size of the button figure is changed according to the time length during which the button figure displayed on the LCD 14 is designated by the player by use of the stick, 24 etc. Hereafter, although the description is made in detail, the same process and the same screen as the button figure size changing process (1) shown in FIG. 7 is briefly described. As shown in FIG. 8, when the button figure size changing process (2) is started, the figure size change selecting screen 120 shown in FIG. 11 is displayed on the LCD 14 in a step S81. In a following step S83, it is determined whether or not the button size is changed. In a case the button size is not changed, “NO” is determined, and the button figure size changing process (2) is directly returned while in a case that the button size is changed, “YES” is determined, a button figure size changing screen 130′ shown in FIG. 13 is displayed on the LCD 14 in a step S85. The button figure size changing screen 130′ is the same as the button figure size changing screen 130 except that the guide lines 132 are not displayed, and therefore, a duplicated description is omitted. In a step S87, it is determined whether or not the operation is started. Here, it is determined whether or not the player starts to point (designate) the button figure 102a by use of the stick 24, etc. If “NO” in the step S87, that is, if the operation is not started, it is determined whether or not to be canceled in a step S89. Here, if it is not canceled, “NO” is determined, and the process directly returns to the step S85 while if it is canceled, “YES” is determined, the button figure size changing process (2) is directly returned. On the other hand, if “YES” in the step S87, that is, if the operation is started, an operation time period starts to be counted in a step S91. Although omitted in FIG. 2, an internal timer of the game apparatus 10 starts to be counted. It is noted that the internal timer counts a unit of time (three seconds, for example), and, when the time is up, is repeatedly reset and started until the button figure size changing process (2) is completed (returned). In a following step S93, it is determined whether or not the unit of time (three seconds, here) elapses. Here, if the unit of time does not elapse, “NO” is determined, and the process directly proceeds to a step S97. On the other hand, if the unit of time elapses, “YES” is determined, the button figure is enlarged by a predetermined value in a step S95, and the process proceeds to the step S97. In the step S95, an enlargement process is executed such that the length from the center of the button figure (design) is extended by a length set in advance. Thus, the button figure is set so as to be gradually enlarged. It is noted that it may be successively enlarged according to the elapse of time. In the step S97, it is determined whether or not the operation is completed. If “YES” in the step S97, that is, if the operation is completed, the button figure size changing process (2) directly is returned. In this case, the size of the button figure is set to the size at a time that the player releases the stick 24, etc. from the LCD 14 (touch panel 22), and the size data is written to the RAM 48 in correspondence to the player character. On the other hand, if “NO” in the step S97, that is, if the operation is not completed, it is determined whether or not the size of the button figure is the maximum value in a step S99. If “NO” in the step S99, that is, if the size of the button figure is not the maximum value, the process directly returns to the step S91. On the other hand, if “YES” in the step S99, that is, the size of the button figure is the maximum value, the button figure size changing process (2) is returned. In this case, the size of the button figure is set to the maximum value, and the size data is written to the RAM 48 in correspondence to the player character. It is noted that if “NO” in the step S83, or if “YES” in the step S89, the size of the button figure is set to the initial value, the size data is written to the RAM 48 in correspondence to the player character. Returning to FIG. 5, when the button figure size changing process is completed, an area on the touch panel 22 corresponding to the display area (closed region) of the button figure changed in a step S41 is set as an operation effective area. That is, a position coordinates data collection on the touch panel 22 corresponding to the display area of the operation button is written to the RAM 48 in correspondence to the player character. It is noted that in a case that the size of the button figure is not changed in the button figure size changing process, the display area of the button figure of the default is set as the operation effective area. Succeedingly, in a step S43 shown in FIG. 6, a button function selecting screen 140 as shown in FIG. 14 is displayed on the LCD 14. As shown in FIG. 14, on the button function selecting screen 140, a function selecting menu displaying area 106 is provided at the upper part of the screen, and a message displaying area 104 is provided at the lower part of the screen. In the function selecting menu displaying area 106, a function (command) prepared as a default is text-displayed. It is noted that these functions are only examples, may be another function. Furthermore, a multiplicity of functions, if only two or more functions, may be displayed. In the message displaying area 104, a message prompting the player to select the function as to the set operation button (A button, here) is displayed. On the button function selecting screen 140, the button figure 102a whose arrangement position and size are determined (set) is displayed according to the arrangement position and the size. On the button function selecting screen 140, a function of the operation button (A button, here) to be set can be selected, and in selecting, merely touching (depressing) the LCD 14 (touch panel 22) with the use of the stick 24, etc. is appropriate. Returning to FIG. 6, in a step S45, it is determined whether or not a button function is selected. The determining process in the step S45 is approximately the same as the process shown in the step S23 in FIG. 5, and therefore, a detailed description is omitted. It is noted that in a case that one operation button has to have a plurality of functions like an action RPG, it is determined whether or not a plurality of functions are selected. If “NO” in the step S45, that is, if the button function is not selected, the process directly returns to the same step S45. That is, a selection of the button function is waited. On the other hand, if “YES” in the step S45, that is, if the button function is selected, the button function is set in a step S47. That is, the function data is written to the RAM 48 in correspondence to the player character. Then, in a step S49, a next button setting selecting screen 150 shown in FIG. 15 is displayed on the LCD 14. The next button setting selecting screen 150 is a screen for selecting whether or not a new button is set, and has the message displaying area 104 at a lower part of the screen. In the message displaying area 104, a message prompting the player to select whether or not a next operation button (B button, here) is to be set is displayed. Furthermore, the next button setting selecting screen 150 is displayed in the same arrangement position and the same size as the operation button (A button, here) already set. It is noted that although illustration is omitted, the set function may be displayed inside the button figure 102a, or its periphery. Furthermore, a selecting operation on the next button setting selecting screen 150 is the same as the selecting operation of the button on the button figure size change selecting screen 120 shown in FIG. 11, and therefore, a detailed description will be omitted here. Returning to FIG. 6, in a succeeding step S51, it is determined whether or not a next operation button is set. If “YES” in the step S51, that is, if the next operation button is set, the process returns to the step S21 shown in FIG. 5. In this case, a button figure selecting screen 100′ as shown in FIG. 16 is displayed in the step S21. The button figure selecting screen 100′ is the same as the button figure selecting screen 100 shown in FIG. 9 except that the operation button (A button, here) already set is displayed on the LCD 14, and therefore, a detailed description is omitted. On the other hand, if “NO” in the step S51, that is, if the next operation button is not set, the button setting process to the touch panel is directly returned. FIG. 17 to FIG. 19 are a flowchart showing a game process based on the operation of the touch panel in the step S11 shown in FIG. 4. When the game process is started, a game image (game screen) 200 shown in shown FIG. 20 is displayed on the LCD 12 in a step S141 shown in FIG. 17. On the game screen 200, a player character 202 and a non-player character 204 are displayed, and a background image is also displayed. For example, the player character 202 is a soldier character, and the non-player character 204 is a character such as an enemy or a villager. As a background image, an object such as a ground, a tree, a building, etc. is displayed. It is noted that as the player character 202, a character first selected by the player is displayed on the screen. In a next step S143, a selecting process of the operated character is executed. Although illustration is omitted, for example, a selection screen for allowing the player to select an arbitrary player character out of a plurality of kinds of player characters is displayed on the LCD 12 (LCD 14 is possible) to prompt the player to select. Here, in a case that another player character is selected, the display is changed to the selected player character (see FIG. 25). However, in a case that another player character is not selected, and canceled, the player character first selected is displayed as it is. In a succeeding step S145, a button arrangement corresponding to the selected operated character (player character) 202 is read from the RAM 48 so as to be displayed and set on the LCD 14. Here, the GPU 52 reads from the RAM 48 button figure data stored in correspondence to the player character 202 in response to an instruction from the CPU core 42, and renders the button figure data in the VRAM 58. In a case that a plurality of operation buttons are set, button figure data in correspondence to all the operation buttons are rendered. At this time, coordinates position data and size data stored in correspondence to the button figure data are also read-out, and thus, the button figure data is rendered in a size at a coordinates position respectively indicated by the size data and the coordinates position data. Furthermore, in the RAM 48, operation effective area data is also stored in correspondence to the button figure data, and therefore, an area on the touch panel 22 corresponding to the display area on which the button figure (operation button) is to be displayed is set as an operation effective area. Succeedingly, in a step S147, a function of each of the buttons is displayed and set. That is, the GPU 52 reads function data stored in correspondence to the button figure data in response to the instruction from the CPU core 42, and writes (overwrites) it to the VRAM 58 so as to display text data as to the function data inside the closed region of the button figure. Then, in a step S149, an operation panel image (screen) 210 shown in FIG. 20 is displayed on the LCD 14. Here, the operation panel screen 210 developed in the VRAM 58, that is, the button figure data describing a name and a function of the operation button is displayed on the LCD 14 by the LCD controller 60 in response to an instruction from the CPU core 42. Accordingly, as shown in FIG. 20, in the game apparatus 10, a game screen 200 is displayed on the LCD 12, and the operation panel screen 210 corresponding to the player character 202 displayed on the game screen 202 is displayed on the LCD 14. Here, operation buttons 212a, 212b and 212c are displayed on the operation panel image 210 in correspondence to the player character 202. Returning to FIG. 17, in a next step S151, a counting process of the game time is executed. It is noted that in a case of executing the process in the step S151 first, a timer for counting the game time (internal timer not shown in the game apparatus 10) starts to count a game time, and in a case of executing the process in the step S151 after that, the counting of the timer is continued. In a succeeding step S153, it is determined whether or not an operation by use of the touch panel 22 is present. If “NO” in the step S153, that is, if the operation by use of the touch panel 22 is not present, the process directly proceeds to a step S161 shown FIG. 18. On the other hand, if “YES” in the step S153, that is, if the operation by use of the touch panel 22 is present, an operation coordinates position is detected on the basis of the operation information detected by the touch panel 22, and it is determined whether or not a coordinates position from the touch panel 22 indicated by the coordinates position data is within the operation effective area in a step S155. That is, it is determined whether or not the operation position by the player is within the closed region of the button figure displayed on the LCD 14. If “NO” in the step S155, that is, if the operation position by the player is not within the closed region of the button figure, it is determined that the operation is not effective, and the process directly proceeds to a step S161. However, if “YES” in the step S155, that is, if the operation position by the player is within the closed region of the button figure, it is determined the operation is effective, a process corresponding to the function of the operated operation button is executed in a step S157. For example, in a case that an operation button 212c is operated on the operation panel screen 210 shown in FIG. 20, the player character 202 checks his foots, a cave, a tree, a drawer of a desk, etc. FIG. 21 shows the game screen 200 and the operation panel screen 210 in a case that the player character 202 checks his foots in response to an operation of the operation button 212c. Here, a message informing the player of coming up with nothing in a case of checking his foots is displayed at the upper left of the game screen 200. Although illustration is omitted, in a case of finding any item, etc., a message indicative of finding the item, etc is displayed. It is noted that although illustration is omitted, in a case that the operation button 212a is operated, the player character 202 talks with the non-player character 204 such as a villager. Furthermore, in a case that the operation button 212b is operated, the player character 202 uses a predetermined item (arms, medicine, etc). Returning to FIG. 17, in a succeeding step S159, the number of times of operations of the operation button is added by 1, and then, the process proceeds to the step S161. Although omitted in FIG. 3, it is appropriate that a counter for counting the number of times of operations consists of a register, and is set in the RAM 48 in correspondence to each operation button. As shown in FIG. 18, in the step S161, it is determined whether or not a state of the operated character, that is, the player character 202a is changed. For example, it is determined whether or not the player character 202 encounters the enemy character, and it is shifted to a battle mode. It is noted that without applying only to a case of shifting to the battle mode, it is determined that the player character 202 is level-up, changed, or evolved. If “NO” in the step S161, that is, if the state of the player character 202 is not changed, the process directly proceeds to a step S167. On the other hand, if “YES” in the step S161, that is, if the state of the player character 202 is changed, a function of each operation button is changed according to a shifted state in a step S163. More specifically, the text data is rewritten in the VRAM 58 by text data indicative of a function of each of the operation buttons in a case of being shifted to the battle mode. Then, in a step S165, the changed function is displayed on each button, and then, the process proceeds to the step S167. It is noted that once that it is shifted to the battle mode, and then, shifted to a non-battle mode through a shift of the state, “YES” is determined in the step S161, and the function of each of the operation buttons is changed according to the shift of the state. For example, when “YES” is determined in the step S161, and it is shifted to the battle mode, a battle screen 220 is displayed on the LCD 12 as shown in FIG. 22. Correspondingly thereto, in the step S165, the operation panel screen 210 including the operation buttons 212a, 212b and 212c that is changed in function for battle mode is displayed on the LCD 14. It is noted that as can be seen from FIG. 22, a message informing the player of being shifted to the battle mode is displayed on the upper left of the battle screen 220. Returning to FIG. 18, in the succeeding step S167, it is determined whether or not a displaying timing of a special button comes. Here, the special button means an operation button generally not displayed on the LCD 14, and is displayed on the LCD 14 according to the predetermined timing (event). For example, the special button is an operation button capable of instructing a command input of a special weapon, and therefore, in a case of executing the game process by use f the operating switch 20, even if a special weapon (function) required to be operated by a plurality of operating switches 20 is selected, it is possible to easily instruct an attack operation. It is noted that the special button 214 may be set similarly to another operation buttons 212a to 212c by the player, and may be set in advance together with its displaying timing (progress of the game or predetermined event) by a programmer or a developer. If “NO” in the step S167, that is, if it is not the displaying timing of the special button, the process directly proceeds to a step S183 shown in FIG. 19. On the other hand, if “YES” in the step S167, that is, if it is the displaying timing of the special button, a special button 214 is displayed on the LCD 14 in a step S169 as shown in FIG. 23, and an area on the touch panel 22 corresponding to the display area (closed region) of the button figure of the special button 214 is set as an operation effective area in a step S171. As can be understood from FIG. 23, in a case that the special button 214 is overlapped by another operation buttons 212a, 212b and 212c, the operation of the special button 214 is handled with a priority. That is, in a case that the coordinates position data of the overlapped area is input from the touch panel 22, the CPU core 42 determines that the special button 214 is operated. In a succeeding step S173, it is determined whether or not the special button 214 is operated. If “NO” in the step S173, that is, if the special button 214 is not operated, it is determined whether or not a display end timing of the special button 214 comes in a step S175. If it is not the display end timing of the special button 214, “NO” is determined in the step S175, and the process directly returns to the step S173. However, if it is the display end timing of the special button 214, “YES” is determined in the step S175, and the process proceeds to a step S179. Furthermore, if “YES” in the step S173, that is, if the special button 214 is operated, a process corresponding to the function set to the special button 214 is executed in a step S177. For example, in a case that the special weapon is set, by attacking the enemy character 204 with the special weapon, its effect or staging is reflected on the battle screen 220, a life of the enemy character 204 is drastically reduced, the enemy character 204 is defeated at one blow, and so on. Then, the special button 214 is erased from the LCD 14 in the step S179, a setting of the operation effective area of the special button 214 is canceled in a step S181, and then, the process proceeds to the step S183. As shown in FIG. 19, it is determined whether or not a unit of time (10 minutes in this embodiment) from the start of the game elapses in the step S183. If “NO” in the step S183, that is, if the unit of time does not elapse, the process directly proceeds to a step S197. On the other hand, if “YES” in the step S183, that is, if the unit of time elapses, it is determined whether or not an operation button whose operation number of times is equal to or less than a predetermined number of times (twenty times, for example) is present in a step S185. If “NO” in the step S185, that is, if the operation button whose operation number of times is equal to or less than a predetermined number of times is not present, the process directly proceeds to a step S191. On the other hand, if “YES” in the step S185, that is, if the operation button whose operation number of times is equal to or less than a predetermined number of times is present, a button figure of the relevant operation button is displayed in a reduced manner by a predetermined value in a step S187, an area on the touch panel 22 corresponding to the display area of the changed (reduced) button figure is set as an operation effective area in a step S189, and then, the process proceeds to the step S191. It is noted that although an illustration is omitted, in a case of displaying in a reduced manner, the size data as to the relevant operation button is changed. That is, the changed size data is written (set) to the RAM 48. In the step S191, it is determined whether or not an operation button whose operation number of times is equal to or more than a predetermined number of times (fifty times, for example) is present. If “NO” in the step S191, that is, if the operation button whose operation number of times is equal to or more than a predetermined number of times is not present, the process directly proceeds to a step S197. On the other hand, if “YES” in the step S191, that is, if the operation button whose operation number of times is equal to or more than a predetermined number of times is present, a button figure of the relevant operation button is displayed in a enlarged manner by a predetermined value in a step S193, and an area on the touch panel 22 corresponding to the display area of the changed button figure is set as an operation effective area in a step S195, and then, the process proceeds to the step S197. It is noted that although. an illustration is omitted, in a case of displaying in an enlarged manner, the size data as to the relevant operation button is changed. That is, the changed size data is written (set) to the RAM 48. Thus, when the process in the steps S183 to S195 is executed, the operation panel screen 210 on which the operation button is changed in size is displayed on the LCD 14 as shown in FIG. 24, for example. Here, a case where the operation button 212a is reduced, and the operation button 212b is enlarged is shown. It is noted that the display area enclosed by dotted lines is the button figure before change. Accordingly, as to the operation button with high frequency of usage, its display area (operation effective area) is enlarged, and as to the operation button with low frequency of usage, its display area is reduced, and whereby, it is possible to improve operability. It is noted that as to the operation button with high frequency of usage, its display area is reduced, and as to the operation button with low frequency of usage, its display area is enlarged, and whereby, it is possible to complicate operability. Thus, it is considered that it is possible to prevent even a skilled player from losing interest in the game. Furthermore, although illustration is omitted, after completion of the reducing and enlarging process of the operation button, if the number of times of operations is reset, the operation button once enlarged or reduced can be enlarged or reduced thereafter, and the size of the display area of the operation button can be changed in size in correspondence to progress of the game. Alternatively, if an operation button whose operation number of times is equal to or less than 0 or a predetermined number of times (five times, for example) per unit of time is present, a relevant operation button may be erased. Furthermore, the “predetermined number of times” in the step S185 or step S191 may be set to a different value for each operation button. Returning to FIG. 19, in the step S197, it is determined whether or not the player character is changed. If “YES” in the step S197, that is, if the player character is changed, the process returns to the step S145. For example, when the player character is changed to select a witch or wizard player character 202′ shown in FIG. 25, an operation panel screen 230 including operation buttons 232a, 232b and 232c having a button figure and a function in a set arrangement position and size is displayed correspondingly thereto. That is, a display state of the operation button is changed. On the other hand, if “NO” in the step S197, that is, if the player character is not changed, it is determined whether or not to be the game end in a step S199. That is, it is determined whether or not the game end is instructed by the player, or whether or not to be game over. If “NO” in the step S199, that is, if it is not the game end, the process returns to the step S151 shown in FIG. 17. On the other hand, if “YES” in the step S199, that is, if it is the game end, a game over flag, although illustration is omitted, is turned on, the game process based on the touch panel operation is returned. According to the first embodiment, a display of the operation button arranged at the predetermined position on the touch panel is changed in correspondence to the progress of the game and according to a frequency of usage, and therefore, it is possible to improve operability. Furthermore, the player can freely set the operation buttons on the touch panel, and executes the game by use of the set operation buttons, and therefore, it is possible to provide ease of operation for every player. Thus, it is possible to improve savor of the game. It is noted that although the touch panel is provided in correspondence to the second LCD in this embodiment, the touch panel may be provided in correspondence to the first LCD, and the touch panel may be provided in correspondence to both of the LCDs. In the former, the operation button set by the player is displayed on the first LCD, and the game screen is displayed on the second LCD. In the latter, a selectively display is possible such that the operation button set by the player is displayed on one LCD, and the game screen is displayed on the other LCD. In addition, although the first LCD and the second LCD are vertically arranged in this embodiment, under certain circumstances, these may be horizontally arranged. Furthermore, although the first LCD and the second LCD are separately provided in this embodiment, dividing one display surface into two, the touch panel is provided in association with at least one display surface. In addition, although a selected button figure is arranged in a pointed coordinates position in this embodiment, a position (area) pointed by a plurality of fingers, etc. is detected so as to be regarded as the display area of the operation button. Thus, an operation button fitted into a shape of fingers of the player is settable. Furthermore, the display area of the operation button is changed depending on the number of times of operations in this embodiment. However, by counting an operation time period of the operated operation button as another operation state, for example, the display area of the operation button may be changed depending on whether or not the accumulated operation time period is equal to or more than a predetermined time period (or equal to or less than predetermined time period). Second Embodiment The game apparatus 10 of the second embodiment is the same as the game apparatus 10 in the first embodiment except for that the operation effective area and the display position as to the operation button set on the touch panel are changed on the basis of the operation state of the player during playing the game, and therefore, a duplicated description will be omitted. It is noted that in the second embodiment, positions of all the operation buttons displayed on the LCD 14 is changed on the basis of an operation state of one notable operation button. FIG. 26 to FIG. 29 show a flowchart of the game process based on the operation of the touch panel in the second embodiment. The flowchart shown in FIG. 26 to FIG. 29 is a flowchart made by deleting the process (step) of changing the size of the operation button, and adding a process (step) of changing a display and an operation effective area of the operation button from and to the flowchart of the first embodiment shown in FIG. 17 to FIG. 19. Briefly, the flowchart shown in FIG. 26 to FIG. 29 is a flowchart made by deleting the steps S151, S159 and S183 to S195 of the flowchart shown in FIG. 17 to FIG. 19, providing steps S211 and S213 between the step S149 and the step S153, and providing steps S215 and S217 between the step S157 and the step S161. The process except for the above description is the same, and therefore, the same reference numerals are applied. Thus, a description is made on only the different steps (S211, S213, S215, S217) here, and a description except for is omitted. As shown in FIG. 26, in the step S149, when the operation panel image (screen) 210 shown in FIG. 20 is displayed on the LCD 14, a cumulative difference (cumulative value of difference) R is reset in the step S211. That is, an accumulator (not illustrated) is reset. The accumulator is for accumulating a difference between a central coordinates (the central position of the operation effective area) of the display position of the current operation button and an operation position coordinates in response to the operation to the touch panel 22 by the player for each operation by the player, and has a register for x coordinate and a register for y coordinate. Accordingly, in the step S211, the register for x coordinate and the register for y coordinate are reset. That is, the data value “0” is set to each of the registers. It is noted that the accumulator may be for general purpose use, and may be mounted on the electronic circuit card 40 inside the game apparatus 10, although not shown in the above-described first embodiment, so as to be accessible by the CPU core 42. In a next step S213, a position correcting counter is reset. That is, a count value n of the position correcting counter is set to “0”. The position correcting counter is, although not illustrated in the above-described first embodiment, a register provided in the RAM 48 of the game apparatus 10. When a process corresponding to the function of the operated operation button is executed in the step S157 as shown in FIG. 27, it is determined whether or not the operated operation button is a notable operation button (A button, for example) in the step S215. If “NO” in the step S215, that is, if the operated operation button is not the notable operation button, the process directly proceeds to the step 161 shown in FIG. 28. On the other hand, if “YES” in the step S215, that is, if the operated operation button is the notable operation button, an operation button position correcting process (see FIG. 30 and FIG. 31) described later is executed in the step S217, and then, the process proceeds to the step S161. In FIG. 28, as described in the first embodiment, the process in the steps S161 to S181 is executed, and then, the process proceeds to a step S197 shown in FIG. 29. That is, the size changing process (step S183 to S195) as to the operation button (and operation effective area) shown in FIG. 19 in the first embodiment is not executed. FIG. 30 and FIG. 31 are a flowchart showing the operation button position correcting process in the step S217 shown in FIG. 27. When the CPU core 42 starts the operation button position correcting process, a difference r between the central coordinates position of the operation button and the operation coordinates position is detected in a step S221. More specifically, the coordinates is divided into an x component and a y component, and the difference (rx, ry) for each of them is detected (calculated). Here, in this embodiment, in the display area of the LCD 14 (this is true for the LCD 12), an upper left apex of the screen is set to an original point (0, 0), and a right direction of the display area is rendered a positive direction of the X axis, and a lower direction of the display area is rendered a positive direction of the Y axis. Furthermore, within the display area, coordinates is assigned to each of dots. On the other hand, detection accuracy of the detection surface of the touch panel 22 is the same as a resolution of the display surface of the LCD 14 as described above, and coordinates data of the operation position coordinates as to a position (dot) subjected to a touch operation is input in response to the touch operation (touching, stroking, depressing) by the player. Furthermore, in this embodiment, on the touch panel 22, an upper left apex of the operable area is set to an original point (0, 0), and a right direction of the operable area is rendered a positive direction of the X axis, and a lower direction of the operable area is rendered a positive direction of the Y axis. That is, a coordinates system of the display area of the LCD 14 and a coordinates system of the operable area of the touch panel 22 are coincident with each other, and therefore, the operation position coordinates indicated by the position coordinates data fetched from the touch panel 22 is used as the position coordinates on the LCD 14 as it is. Accordingly, in the step S221, the x component and the y component of the difference r is evaluated by a simple arithmetic operation (subtraction). More specifically, according to an equation 1, the difference r (rx, ry) is evaluated. It is noted that the central coordinates position of the operation button is rendered (X1, Y1), and the operation coordinates position is rendered (X2, Y2). r(rx, ry)=(X1, Y1)−(X2, Y2)=(X1−X2, Y1−Y2) [Equation 1] In a next step S223, differences r is accumulated by use of the differences calculated in the step S221. That is, the cumulative difference R is updated. More specifically, each of data value Rx of the register for x coordinate of the accumulator and data value Ry of the register for y coordinate is updated according to an equation 2. Rx=Rx+rx [Equation 2] Ry=Ry+ry Succeedingly, in a step S225, the position correcting counter is updated. That is, the position correcting counter is incremented (count value n=n+1). Then, in a step S227, it is determined whether or not the count value n of the position correcting counter is “100”. If the count value of the position correcting counter is less than “100”, “NO” in the step S227, the operation button position correcting process is directly returned as shown in FIG. 31. However, if the count value of the position correcting counter is equal to “100”, “YES” in the step S227, and an average value of the differences r is calculated according to the equation 3 in a next step S229. average value=R/n=(Rx/n, Ry/n) [Equation 3] In a succeeding step S231, if a notable operation button is moved on the basis of the calculated average value, it is determined whether or not the central position coordinates of the operation button exceeds an upper. In this embodiment, the upper is a central position coordinates of the figure of the operation button (and operation effective area) so as to prevent the figure of the operation button (and operation effective area) from running off the LCD 14, and set by a different value corresponding to the figure of the notable operation button. In this embodiment, the upper is set on the basis of the size of the operation button. For example, if the notable operation button is an A button, the upper is set on the basis of the size (La). More specifically, as shown in FIG. 32 (A), each of the uppers in the x axis direction is defined by La (x=La) and a maximum value in the x direction of the display area on the LCD 14−La (x=maximum value−La), and each of the uppers in the y axis direction is defined by La (y=La) and a maximum value in the y direction of the display area on the LCD 14−La (y=maximum value−La). Although illustration is omitted, the uppers are similarly set for another operation button. It is noted that the upper may arbitrarily be set by the programmer or the developer of the game. Furthermore, whether or not the central position coordinates of the operation button exceeds the upper depends on, in a case the average value of the calculated differences r is subtracted from the central position coordinates of the operation button to correct the position, whether or not the corrected central position coordinates is out of the range defined by the uppers in the x axis direction and the uppers in the y axis direction. If “NO” in the step S231, that is, if an operation button exceeding the uppers is not present, positions as to all the operation buttons in the operation effective area are changed on the basis of the calculated average value in a step S233 shown in FIG. 31, the display positions of all the operation buttons (figure) are changed on the basis of the calculated average value in a step S235, and then, the process proceeds to a step S241. That is, in the step S233, the average value of the calculated differences r is subtracted from each of the coordinates position data as to the data of the operation effective area correspondingly stored in each of the operation buttons displayed on the LCD 14. In the step S235, the average value of the calculated differences r is subtracted from the coordinates position data correspondingly stored in each of the operation buttons displayed on the LCD 14. On the other hand, if “YES” in the step S231, that is, if the operation button exceeds the uppers, the positions of all the operation effective areas are changed on the basis of the upper in a step S237 shown in FIG. 31, and the display positions of all the operation buttons (figures) are changed on the basis of the upper in a step S239, and then, the process proceeds to a step S241. For example, as shown in FIG. 32 (B), assuming that the central position coordinates of the operation button (notable operation button) moved on the basis of the average value exceeds the upper (x=La, for example). In this embodiment, in such a case, a point of intersection of a line segment connecting the central position coordinates of the current operation button to be moved and the central position coordinates of the operation button moved based on the average value, and a line defined as the upper (x=La, here) is defined as the central position coordinates of the moved operation button. This is the central coordinates of the operation button (operation effective area and display position) moved on the basis of the upper. Furthermore, the changed operation effective area and the changed display position as to the operation button except for the notable operation button is evaluated by subtracting a difference between the central position coordinates of the current notable operation button and the central coordinates position of the moved notable operation button. It is noted that in a case that the notable operation button is moved on the basis of the average value, when it exceeds the upper, the operation effective areas and the display positions of all the operation buttons are changed on the basis of the upper in this embodiment. However, by determining whether or not the upper is exceeded for each operation button, the operation effective area and the display position is separately changed on the basis of the average value or the upper. According to the above-described process in the steps S233 and the step S235, or the steps S237 and the S239, as shown in FIG. 33, the operation effective area and the display position as to the operation button on the LCD 14 are moved. In FIG. 33, the operation effective area and the display position of the operation button to be moved is represented by dotted lines, and the operation effective area and the display position of the moved operation button is represented by a solid line. Returning to FIG. 31, in the step S241, a message for changing the display position is displayed. That is, as described above, a message informing that the operation effective area and the display position of the operation button on the LCD 14 are moved is displayed on the LCD 12 (game screen 200) as shown in FIG. 34. It is noted that in place of the message display, a message by a notification sound or a voice may be output, or both of the message display and the message output by the notification sound or the voice may be executed. In a succeeding step S243, the cumulative difference accumulator is reset, in a step S245, the position correcting counter is reset, and then, the operation button position correcting process is returned. According to the second embodiment, the operation effective area and the display position as to the operation button provided on the LCD is moved on the basis of the operation state of the player during the play, and therefore, a button arrangement according to a size of fingers and the hands of the player, an operation pattern, a habit of operation is possible. That is, it is possible to improve operability. Furthermore, the display area of the operation button is also changed, and therefore, it is possible to easily inform that the operation effective area is changed. It is noted that in the second embodiment, the operation effective area and the display position of the operation button is changed on the basis of the cumulative value of differences by a predetermined number of times. However, every time that the difference is detected (each time), the operation effective area and the display position may be changed on the basis of the difference. Furthermore, although a message informing that the display position of the operation button is changed is displayed in the second embodiment, to what extent the change is made may be displayed by a message, numerical value, etc. Thus, it is possible for the player to easily know his own operation pattern, habit, etc. Third Embodiment The game apparatus 10 in the third embodiment is the same as the game apparatus 10 in the first embodiment except for that on the basis of the operation state of the player during the game, the size of the button figure and the operation effective area as to the operation button provided on the LCD are changed, and the operation effective area and the display position as to the operation button are moved and therefore, a duplicated description will be omitted. Briefly, the game apparatus 10 in the third embodiment is an embodiment made by adding to the game apparatus 10 in the first embodiment the process of moving the operation effective area and the display position as to the operation button in the game apparatus 10 in the second embodiment. That is, a process (S211, S213, S215, S217) of moving the operation effective area and the display position as to the operation button is added to a process of the game process based on the touch panel operation in the first embodiment shown in FIG. 17. More specifically, a part of the game process based on the touch panel operation in the third embodiment is shown in FIG. 35 and FIG. 36. Although illustration is omitted, another part of the game process based on the touch panel operation is the same as the flowchart shown in FIG. 17 and FIG. 18. As shown in FIG. 35, the steps S211 and S213 are provided between the step S149 and the step S151. Furthermore, as shown in FIG. 36, after the step S159, the steps S215 and S217 are provided. A description as to each of the processes in the steps S211, S213, S215 and S217 is made in detail in the second embodiment, and therefore, this is omitted here. According to the third embodiment, the size of the figure and the operation effective area as to the operation button is changed, and the operation effective area and the display position as to the operation button are changed, thus, it is possible to further improve operability. Fourth Embodiment The game apparatus 10 in the fourth embodiment is the same as the game apparatus 10 in the above-described second embodiment or third embodiment except for that only the operation effective area of the operation button provided on the LCD 14 is changed on the basis of the operation state of the player during the game, and therefore, a duplicated description is omitted. Briefly, in the operation button position correcting process, only the operation effective area of the operation button provided on the LCD 14 is moved on the basis of the operation state of the player. Accordingly, in the operation button position correcting process shown in the second embodiment, a changing process (steps S235, S239) of the display position as to the operation button is deleted. Furthermore, the display position of the operation button is not changed, and therefore, a process of displaying a message of changing the display position of the operation button is also deleted (step S241). FIG. 37 shows a flowchart showing a part of the operation button position correcting process in the fourth embodiment. As described above, the process in the steps S235, S239 and S241 is deleted. It is noted that another part of the operation button position correcting process is the same as the flowchart of the second embodiment shown in FIG. 30, and therefore, the illustration is omitted. Accordingly, in the fourth embodiment, when a notable operation button is operated predetermined number of times (one hundred times, for example), only the position of the operation effective area is corrected as shown in FIG. 38. According to the fourth embodiment, the operation effective area is corrected according to a game operation, and therefore, a button setting according to a habit, etc. of operation by the player can be performed. It is noted that although only the operation effective area is changed in the fourth embodiment, and a message, etc. about-that is not output, due to a case of accepting an operation except for the figure of the operation button, a message, etc. indicative of changing only the operation effective area may be output so as to prevent the player from taking for a breakdown of the game apparatus. Furthermore, although the operation effective area of the operation button is changed on the basis of the cumulative value of the differences by the predetermined number of times in the fourth embodiment, the operation effective area may be changed every time that a difference is detected and on the basis of the difference. Fifth Embodiment The game apparatus 10 of the fifth embodiment is the same as the second embodiment or the third embodiment except for that the operation button position correcting process is executed as to each operation button, and therefore, a duplicated description is omitted. Briefly, the operation button position correcting process is executed for each of the operation buttons set on the LCD 14 on the basis of an operation state of the player. Accordingly, in the operation button position correcting process in the second embodiment shown in FIG. 30 and FIG. 31, a changing process of the operation effective area and the display position of the operation button (S233, S235, S237, S239) is executed on only one notable operation button. That is, a part of the operation button position correcting process is shown in a flowchart in FIG. 39. It is noted that another part of the operation button position correcting process is the same as the flowchart shown in FIG. 30, and therefore, the illustration is omitted. In the operation button position correcting process of the fifth embodiment shown in FIG. 39, the operation effective area and the display position of the operation button as to one notable (relevant) operation button is changed on the basis of the calculated average value or the upper. (steps S233′, S235′, S237′, S239′). Accordingly, when the operation button position correcting process is executed for each operation button, it is changed to a different position for each operation button as shown in FIG. 40. Thus, it may be possible that the operation button can be arranged according to a position of the finger of the player and a habit of operation. According to the fifth embodiment, the operation effective area and the display position of the operation button are modified for each operation button, and therefore, it is possible to further improve operability. Sixth Embodiment The game apparatus 10 in the sixth embodiment is the same as the second embodiment except for that the operation position coordinates is recorded every time that a notable operation button is operated, and the operation effective areas and the display positions of all the operation buttons are moved such that the notable operation button is moved to the operation position coordinates being the highest frequency of the operation, and therefore, a duplicated description is omitted. Specifically, the operation button position correcting process is shown in FIG. 41 and FIG. 42. Hereafter, the content thereof is described, but the content the same as the above-described content is briefly described. Referring to FIG. 41, when the CPU core 42 starts the operation button position correcting process, in a step S221′, the operation coordinates position is stored in the other storing area 72 of the RAM 48, that is, the buffer area. In a succeeding step S225, the position correcting counter is updated. Then, in a step S227, it is determined whether or not the count value n of the position correcting counter is “100”. If “NO” here, the operation button position correcting process is directly returned as shown in FIG. 42. However, If “YES”, an operation coordinates position being the highest frequency of operation (the greatest in number) out of the operation coordinates positions stored in the buffer area is extracted in a step S229′. It is noted that if a plurality of operation coordinates positions having the highest frequency of the operation exist, an average value thereof is calculated, or any one of them is selected at random. In a succeeding step S231, it is determined whether or not the upper is exceeded. If the upper is not exceeded, “NO” in the step S231, and the process proceeds to a step S233″ shown in FIG. 42. However, if the upper is exceeded, “YES” in the step S231, and the process proceeds to a step S237 shown in FIG. 42. As shown in FIG. 42, in the step S233″, the data constellation is moved such that the operation effective area of the notable operation button is moved to the extracted operation coordinates position, and similarly, as to another operation button, the data constellation is moved in parallel. Then, in a step S235″, the display position of each operation button is changed on the basis of the extracted operation coordinates position similarly to the operation effective area, and the process proceeds to a step S241. Furthermore, in the step S237, the operation effective areas of all the operation buttons are changed on the basis of the upper, and in the step S239, similarly, the display positions of all the operation buttons are changed on the basis of the upper, and the process proceeds to the step S241. In the step S241, a message for changing the display position is displayed on the game screen 200, and in a step S243′, all the operation coordinates positions stored in the buffer area are cleared (erased). Then, the position correcting counter is reset, and then, the operation button position correcting process is returned. According to the sixth embodiment, the operation button position is corrected to a position having the highest frequency of operation, and therefore, similairy to the above-described embodiment, the button setting according to a habit of operation by the user, etc. can be performed, capable of improving operability. It is noted that in the sixth embodiment, the operation button position is corrected to the position being the highest frequency of the operation. However, an average value of the detected all of the operation coordinates positions is calculated to correct the operation effective area and the display position of the operation button to a position indicated by the calculated average value. Furthermore, although an illustration, etc. is omitted, the operation button position correcting process in the sixth embodiment can be applied to the third embodiment and the fourth embodiment. In addition, as shown in the fifth embodiment, the operation button position correcting process shown in the sixth embodiment can also be executed for each operation button. Seventh Embodiment The game apparatus 10 in the seventh embodiment is the same as the game apparatus 10 in the above-described second embodiment or the third embodiment except for that only the display position of the operation buttons provided on the LCD 14 is moved on the basis of an operation state of the player during the game, and therefore, a duplicated description is omitted. Briefly, in the operation button position correcting process, only the display position of the operation button set on the LCD 14 is moved according to an operation state of the player. Accordingly, in the operation button position correcting process in the second embodiment shown in FIG. 31, the process for changing the operation effective area as to the operation button (step S233, S237) is deleted. Furthermore, a process for changing the display position of the operation button (step S235, S239) is inversely moved (subjected to an adding process) on the basis of the average value. That is, a part of the operation button position correcting process in the seventh embodiment is shown in a flowchart in FIG. 43. It is noted that another part of the operation button position correcting process is the same as the flowchart of the second embodiment shown in FIG. 30, and therefore, the illustration is omitted. As shown in FIG. 43, in the operation button position correcting process of the seventh embodiment, if the operation button that exceeds the upper is not present in the step S231 shown in FIG. 30, (that is, an average value of the calculated differences r is added to the central position coordinates of the operation button to correct the position, the corrected central position coordinates is within a range defined by the uppers in the x axis direction and the uppers in the y axis direction), the display positions of all the operation buttons (figures) are changed on the basis of the calculated average value in a step S235a, and then, the process proceeds to the step S241. That is, in the step S235a, the calculated average value of the differences r is added to the coordinates position data correspondingly stored for each of the operation buttons displayed on the LCD 14. Accordingly, in the seventh embodiment, when the notable operation button is operated predetermined number of times (one hundred, for example), only the display position of the operation button is corrected as shown in FIG. 44. According to the seventh embodiment, since only the display position of the button figure is corrected according to the game operation leaving the operation effective area of the button figure as it is, by changing the display position of the button figure according to a habit of operation, etc. by the player, the operation position of the player can be lead to the neighbor of the center of the operation effective area. It is noted that although the display position of the operation button is changed on the basis of the cumulative value by the predetermined number of times in the seventh embodiment, every time that the difference is detected (every time), the display position may be changed on the basis of the difference. In addition, in these embodiments, an example of the operation button as a figure is described, but it is not limited thereto, and another figure, if being an object to be operated by the player, is applicable. For example, a character of a target of a shooting game, etc. is applicable. Eighth Embodiment The game apparatus 10 of the eighth embodiment is the same as the first embodiment except for that in a case that the button is set on the touch panel 22, the button figure is freely rendered by the player, and the operation effective area is set to the button figure rendered by the player, and therefore, a duplicated description is omitted. FIG. 45 is an illustrative view showing a memory map of the RAM 48 of the game apparatus 10 in the eighth embodiment. The memory map in FIG. 45 is approximately the same as the memory map shown in FIG. 3, and therefore, a duplicated description is omitted. As understood from FIG. 45, in the memory map of the RAM 48 in the eighth embodiment, in place of the operation button storing area 82 of the second player character shown in FIG. 3, the operation button storing area 84 of the second player character is provided. In the operation button storing area 84 of the second player character, a setting A button storing area 840, etc. is provided. The setting A button storing area 840 stores attribute information as to the A button set in correspondence to the second player character by the player. Here, the “A button” is a name applied in order to distinguish the operation button set in correspondence to the second player character by the player as a matter of convenience, and does not mean that it has the same function as that of the A button 20d and the B button 20e. Furthermore, this does not mean that it has the same figure, position, size, function, and operation effective area as the A button, etc. set in correspondence to the first player character. It is noted that it can be set so as to have the same function as the A button 20d and the B button 20e, and set so as to have the same figure, etc. as the A button set in correspondence to the first player character, etc. The setting A button storing area 840 stores figure data 840a, coordinates position data 840b, function data 840c, and operation effective area data 840d. For example, the figure data 840a is data (referred as “rendering” in the drawing as a matter of convenience) obtained by rendering freely the figure (pattern) by the player. It is noted that the image data of the figure (pattern) actually rendered may be stored. The coordinates position data 840b is data as to a plurality of coordinates positions ((Xd, Yd), (Xe, Ye), . . . ) for specifying (defining) a position, a shape (appearance) and a size of the figure (pattern) freely rendered by the player. The function data 840c is data indicative of a command input of “use a magic” or a label indicative of the command. Then, the operation effective area data 840d is a coordinates position data collection for determining whether or not an operation of the operation button (A button, here) freely rendered by the player is effective. It is noted that in a case that the player freely renders the figure (pattern) of the button, the plurality of coordinates data for specifying the position, the shape (appearance) and the size of the figure are stored as the coordinates position data, and therefore, dissimilar to the case where the figure prepared (as default) in advance is stored in the first embodiment, the size data is not present. Furthermore, as understood from FIG. 45, it seems that the player sets the A button and the B button with respect to the first player character by use of the button figure of the default. That is, there are cases of executing the button setting process by use of the button figure as the default and of executing the button setting process by freely rendering the button figure by the player in the eighth embodiment. Accordingly, although an illustration is omitted in FIG. 4, before shifting to the process in the step S5, which button setting process is to be executed is selected by the player. FIG. 46 shows a part of the flowchart of a button setting process to the touch panel in the eighth embodiment. Here, as described above, the button figure is freely rendered by the player. Accordingly, when the button is rendered, the size of the button is also determined, and therefore, the size changing process of the button figure as described in the first embodiment is not executed. In addition, another part of the button setting process with respect to touch panel in the eighth embodiment is the same as the flowchart in FIG. 6, and therefore, drawings and a detailed description as to another part is omitted. Furthermore, the button setting process to the touch panel described in the first embodiment and the duplicated content are simply described. Referring to FIG. 46, when the button setting process to the touch panel in the eighth embodiment is started, a button rendering instructing screen 160 as shown in FIG. 47 is displayed on the LCD 14 in a step S311. On button rendering instructing screen 160, a message displaying area 104 is provided at a lower part of the screen. At a start of displaying the button rendering instructing image 160, no screen display is performed except for the message displaying area 104. In the message displaying area 104, a message for prompting for a rendering of the button figure as to the operation button (A button, here) to be set is displayed. Accordingly, the player can render the button figure by stroking the surface of the LCD 14 (touch panel 22) by use of the stick 24, etc. to be described later. It is noted that in a case of rendering it with a finger, a surface to be contacted to the LCD 14 (touch panel 22) is larger than that of the stick 24, it may be impossible to render a precise line (button figure), and therefore, it is considered good to perform rendering by use of the stick 24. Accordingly, in the button setting process to the touch panel, a description is made on a case where an operation is made by use of the stick 24. In a next step S313, it is determined whether or not rendering of the button figure is started. More specifically, it is determined whether or not the stick 24 touches (depresses) the LCD 14 (touch panel 22), that is, whether or not the coordinates position data is input from the touch panel 22. If “NO” in the step S313, that is, if the rendering of the button figure is not started, it is determined whether or not to be canceled in a step S315. Here, if it is not canceled, “NO” is determined, and the process directly returns to the step S311 while if it is canceled, “YES” is determined, and the process proceeds to a step S49 shown in FIG. 6. On the other hand, if “YES” in the step S313, that is, if the rendering of the button figure is started, the coordinates position data of a depressing point or a contacted point is sequentially read out in a step S317. At this time, read coordinates position data is temporarily written to not the operation button storing area 70 but another area 72. Here, the reason why the coordinates position data is sequentially read is that it is necessary to display the button figure freely rendered by the player or to set the operation effective area. It is noted that a time interval for reading the coordinates position data, that is, a scan time (a time period for taking one circle of a closed loop consisting of S317, S319, S321) can be set to a speed equal to or less than the reading speed of the coordinates position data in the touch panel 22. However, the shorter the scan time is set, the larger the coordinates position data (coordinates position data to be set) to be read is while the longer the scan time is set, the rougher the image at a time of displaying the button figure becomes. Therefore, the scan time has to be set to an adequate value by an examination, etc. In a step S319, the depressing point or the contacted point is displayed so as to be rendered. Here, a display of the LCD 14 is controlled such that a dot is plotted (rendered) at the coordinates position indicated by the coordinates position data fetched from the touch panel 22. In a following step S321, it is determined whether or not the rendering of the button figure is stopped (completed). That is, it is determined whether or not in response to a release of the stick 24 from the LCD 14 (touch panel 22) by the player, there is no input of the coordinates position data from the touch panel 22. If “NO” in the step S321, that is, if the rendering of the button figure is not stopped, the process directly returns to the step S317. On the other hand, if “YES” in the step S321, that is, if the rendering of the button figure is stopped, it is determined whether or not the coordinates of a stopping point is a starting point or an end point in a step S323. That is, it is determined whether or not the rendered button figure becomes a closed region. This is because that the closed region (display area) of the rendered button figure is set as an operation effective area. In a case that the button figure is rendered within the display area of the LCD 14, the starting point and the stopping point need to be coincident with each other, and in a case of starting to render from the end point defining a range of the display area on the LCD 14 (forming a circumference of the display area), the stopping point needs to be coincident with the starting point or becomes another end point. In a case that the starting point is an end point (referred to as “first end point” for the sake of convenience of description), the stopping point is another end point (referred to as “second end point” for the sake of convenience of description), the closed region of the button figure is formed by a line connecting the first end point and the second end point rendered by the player and a line connecting the first end point and the second end point in the circumference of the display area of the LCD 14 (see FIG. 51). If “NO” in the step S323, that is, if the coordinates of the stopping point is not the starting point or the end point, it is determined that an adequate button figure is not rendered, and a rendering failure screen 170 as shown in FIG. 48 is displayed in a step S325. On the rendering failure screen 170, a message displaying area 104 is provided at a lower part of the screen. In the message displaying area 104, a message indicative of failing in rendering the operation button (A button, here) and a message prompting a determination (selection) whether or not the button figure as to the operation button is re-rendered are displayed. Returning to FIG. 46, in a succeeding step S327, it is determined whether or not the button figure of the button is re-rendered. That is, it is determined whether or not “YES” is selected on the rendering failure screen 170. If “YES” is determined here, that is, if it is re-rendered, the process directly returns to the step S311. However, if “NO” is determined, that is, if it is not re-rendered, the process proceeds to the step S49 shown in FIG. 6. Furthermore, if “YES” in the step S323, that is, if the coordinates of the stopping point is the starting point or the end point, and the rendered button figure forms the closed region, the display area (closed region) of the rendered figure (button figure) is set to an operation button position, that is, the coordinates position data written to the another area 72 is written to the RAM 48 as the coordinates position data in correspondence to the player character selected in the step S3 in a step S329. Then, in a step S331, an area on the touch panel 22 corresponding to the display area of the set operation button is set as an operation effective area. The setting is the same as the button setting process to the touch panel described in the first embodiment. Thereafter, the process proceeds to the step S43 shown in FIG. 6 to set a function of the operation button, and execute a next operation button setting, etc. It is noted that a button function selecting screen and a next button setting selecting screen displayed in the button setting process to the touch panel in the eighth embodiment are the same as the respective screens (140, 150) described in the button setting process to the touch panel in the first embodiment except for that the button figure freely rendered by the player is displayed on the LCD 14. Briefly, as shown in FIG. 49, on the button function selecting screen 180, a function selecting menu displaying area 106 is provided at an upper part of the screen, and the message displaying area 104 is provided at a lower part of the screen. Furthermore, the button figure 108 rendered by the player is displayed. In addition, as shown in FIG. 50, on the next button rendering selecting screen 190, the message displaying area 104 is provided at a lower part of the screen, and the button figure 108 rendered by the player is displayed. Also, as shown in FIG. 51, on a button rendering instructing screen 160′ for rendering the button figure of the next operation button, the message displaying area 104 is provided at a lower part of the screen, and the button figure 108 that has already been written by the player is displayed. On the button rendering instructing screen 160′, a state in which the button figure as to the next operation button (B button, here) is rendered is shown. However, at a start of displaying the screen 160′, only the button figure of the operation button (button A, here) that has already been rendered and the message area are displayed. According to the eighth embodiment, the player can freely render the figure of the operation button, and sets the operation effective area with respect to the rendered figure, and therefore, it is possible for all the players to operate with ease similarly to the first embodiment. Furthermore, in the eighth embodiment, the size of the button figure and the operation effective area cannot be changed, but the position thereof is changeable. That is, according to an operation state in the above-described game process based on the touch panel operation, a position of any one of the button figure and the operation effective area can be changed (moved). As a method of changing the position, any one of methods shown in the second embodiment to the seventh embodiment can be adopted. It is noted that in the eighth embodiment, the plurality of coordinates corresponding to the button figure and the operation effective area of the operation button are stored, and therefore, in a case that the position of the button figure and the operation effective area are changed (moved), the plurality of coordinates are moved (in parallel). It is noted that although in each of the above-described embodiment, the touch panel provided on the display is used as one example of a pointing device, another pointing device is useable. Here, the pointing device is for designating an input position and coordinates on the screen, and is applicable to a case where a directing operation within the display area of the figure or the operation effective area by use of, for example, a mouse, a track pad, a track ball, etc. is performed. It is noted that in this case, an image of a cursor, a mouse pointer, etc. for directing an input position (directing position) by the player is displayed on the screen. Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a game apparatus and a storage medium storing a game program. More specifically, the present invention relates to a game apparatus executing a game process by operating a pointing device provided in association with a display portion, and a storage medium storing a game program. 2. Description of the Prior Art An example of this kind of a conventional game apparatus is disclosed in a Japanese Patent Laying-open No.1994-285257 [A63F 9/22, A63F 5/04] laid-open on Oct. 11, 1994. An electronic composite game apparatus of this prior art can be executed by selecting any one of a plurality of kinds of games, and according to the kind of the selected game, a switch displayed on a display operation plate provided with a touch panel is changed. Furthermore, only a switch required to be displayed in correspondence with progress of the selected game is sequentially generated on the display operation plate. Another example of this kind of a conventional game apparatus is disclosed in a Japanese Patent Laying-open No. 1994-285259 [A63F 9/22] laid-open on Oct. 11, 1994. The liquid crystal controller of the other prior art is provided with a touch panel and a liquid crystal monitor on the controller main body, and is connected to a game machine main body to display operation information to be transmitted from the game machine main body on the liquid crystal monitor. The operation information is stored in a game cartridge loaded into the game machine main body, and therefore, it is possible to change the operation information according to a kind of the game similarly to the above-described prior art. However, in the above-described both prior arts, the switch (operation information) to be displayed on liquid crystal screen depending on the kind or in correspondence with the game is merely changed in number and function, and an operation effective area and a display area of the switch are not changed on the basis of an operation state of the displayed switch. For example, the game controller is generally made for a right-handed player, and therefore, it is difficult to operate for a left-handed player. Furthermore, a position, a size, etc. of the switch that is operable for the player is different between respective players. Furthermore, it is impossible to set and modify the switch according to a way (habit) of operation, frequency of operation by the player. | <SOH> SUMMARY OF THE INVENTION <EOH>Therefore, it is a primary object of the present invention to provide a novel game apparatus and storage medium storing a game program. Another object of the present invention is to provide a game apparatus and a storage medium storing a game program that allows a player to freely display and set an operation figure at an arbitrary position of a display portion. The other object of the present invention is to provide a game apparatus and a storage medium storing a game program capable of changing an operation effective area according to an operation manner of the operation figure by the player. A further object of the present invention is to provide a game apparatus and a storage medium storing a game program capable of changing a display area of the operation figure according to an operation manner of the operation figure by the player. A game apparatus utilizing a pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, and a game processing means. The display portion displays one or more figures to be operated by a player. The figure position setting means sets a figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting means sets an area on the touch panel in correspondence to the display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. Then, the game processing means executes a game process corresponding to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. More specifically, the game apparatus ( 10 : a reference numeral corresponding in the “preferred embodiment” described later and so forth) is provided with the display portion ( 14 ). The display portion ( 14 ) displays one or more figures to be operated by the player. For example, the pointing device ( 22 ) is provided in association with the display portion ( 14 ). The figure position setting means ( 42 , S 37 , S 329 ) sets the figure at an arbitrary position of the display portion ( 14 ) on the basis of the instruction from the player. The operation effective area setting means ( 42 , S 41 , S 331 ) sets the display area of the figure set by the figure position setting means ( 42 , S 37 , S 329 ) as the operation effective area. The operation coordinates position detecting means ( 42 , S 153 ) detects the operation coordinates position the on the basis of the operation information detected by the operation of the pointing device ( 22 ). The operation coordinates position determining means ( 42 , S 155 ) determines whether or not the operation coordinates position detected by the operation coordinates position detecting means ( 42 , S 153 ) is within the operation effective area. That is, it is determined whether or not the set figure is operated. The game processing means ( 42 , S 157 ) executes the game process corresponding to the operation of the figure to which the operation effective area is set when it is determined to be within the operation effective area by the operation coordinates position determining means ( 42 , S 155 ). According to the present invention, it is possible to freely set the figure at an arbitrary position of the screen, and it is possible to set the figure at a position suitable for operation for each player, capable of improving operability. In one aspect of this invention, a figure selecting means for selecting a figure to be displayed on the display portion out of a plurality of kinds of figures is further provided, and the figure position setting means sets the figure selected by the figure selecting means at an arbitrary position of the display portion. More specifically, the game apparatus ( 10 ) is further provided with the figure selecting means ( 42 , S 21 , S 23 ). The figure selecting means ( 42 ) selects the figure to be displayed on the display portion ( 14 ) out of the plurality of kinds of figures. The figure position setting means ( 42 , S 37 , S 329 ) sets the figure selected by the figure selecting means ( 42 , S 21 , S 23 ) at the arbitrary position of the display portion. Accordingly, a figure to suit the needs or preferences of the player out of the various kinds of figures can be selected. In one embodiment of this invention, the figure position setting means sets the display area of the figure rendered on the display portion according to the operation of the pointing device by the player as a figure position. More specifically, the figure position setting means ( 42 , S 37 , S 329 ) sets the display area of the figure rendered on the display portion ( 14 ) according to the operation of the pointing device ( 22 ) by the player as the figure position. For example, the player can freely render the figure. At this time, a position of the figure is set, and a shape and a size thereof are also set. Thus, the player can freely render the figure, capable of improving a savor of the game. In one aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and a display position changing means for changing the display position of the figure on the basis of the operation state detected by the operation state detecting means are further provided. More specifically, the game apparatus further comprises the operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′) and the display position changing means ( 42 , S 235 , S 235 ′, S 235 ″, S 235 a, S 239 ). The operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′) detects the operation state of the figure, and the display position changing means ( 42 , S 235 , S 235 ′, S 235 ″, S 235 a, S 239 ) changes the display position of the figure on the basis of the operation state detected by the operation state detecting means. Accordingly, by changing the display position of the figure according to a habit of operation, etc. of the player, it is possible to guide an operation position of the player so as to be coincident with the center of the operation effective area. In one embodiment of this invention, the operation effective area setting means sets the display area of the figure changed by the display position changing means as an operation effective area. More specifically, the operation effective area setting means ( 42 , S 41 , S 331 ) sets the changed display area of the figure as an operation effective area. That is, the position of the operation effective area is also changed. Thus, it is possible to easily inform the player that the position of the operation effective area is changed. In another aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and an operation effective area changing means for changing the operation effective area of the figure on the basis of the operation state are further provided. More specifically, the game apparatus comprises the operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′) and the operation effective area changing means ( 42 , S 233 , S 233 ′, S 233 ″, S 237 ). The operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′) detects the operation state of the figure, the operation effective area changing means ( 42 , S 233 , S 233 ′, S 233 ″, S 237 ) changes the operation effective area of the figure according to the detected operation state. That is, the display state by the player is reflected on the operation effective area. Accordingly, the position of the operation effective area can be changed according to an operation pattern, habit, etc. by the player, capable of improving operability. In the other aspect of this invention, a figure size changing means for changing a size of the figure displayed on the display portion is further provided, and the operation effective area setting means sets a display area of the figure changed by the figure size changing means as an operation effective area. More specifically, the figure size changing means ( 42 , S 39 , S 73 , S 95 ) changes the size of the figure displayed on the display portion ( 14 ). The operation effective area setting means ( 42 , S 41 , S 331 ) sets the display area of the figure changed by the figure size changing means ( 42 , S 39 , S 73 , S 95 ) as the operation effective area. Thus, it is freely change the size of the displayed figure. For example, the figure being high frequency of usage is displayed in an enlarged manner, and the figure being low frequency of usage is displayed in a reduced manner, and this makes it easy to operate. In one embodiment of this invention, the figure size changing means changes the size of the figure according to an operation time of the pointing device by the player. More specifically, the figure size changing means ( 42 , S 39 , S 95 ) changes the size of the figure according to the operation time of the pointing device ( 22 ) by the player. For example, the longer the operation time is, the larger the figure is rendered, or the figure is gradually rendered large for each unit of time. Thus, the size of the displayed figure is changed according to the operation time, and therefore, it is easy to operate. In another aspect of this invention, an operation state detecting means for detecting an operation state of the figure, and a figure display area changing means for changing the display area of the figure on the basis of the operation state detected by the operation state detecting means are further provided, and the operation effective area setting means sets the display area of the figure changed by the figure display area changing means as an operation effective area. More specifically, the game apparatus ( 10 ) further comprises the operation state detecting means ( 42 , S 159 , S 185 , S 191 ) and the display area changing means ( 42 , S 187 , S 193 ). The operation state detecting means ( 42 , S 159 , S 185 , S 191 ) detects the operation state of the figure, and the display area changing means ( 42 , S 187 , S 193 ) changes the display area of the figure on the basis of the detected operation state. Here, the operation effective area setting means ( 42 , S 89 , S 195 ) sets the changed display area as the operation effective area. Thus, the display area of the figure (size) is modified according to the operation state of the displayed figure, capable of changing the display of the figure depending on the frequency of usage of the figure. In the other aspect of this invention, a game proceeding detecting means for detecting a game proceeding and a figure display state changing means for changing a display state of the figure displayed on the display portion when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means are further provided, and the operation effective area setting means sets the display area of the figure changed by the figure display state changing means as an operation effective area. More specifically, the game proceeding detecting means ( 42 , S 161 , S 167 , S 197 ) detects the game proceeding. The figure display state changing means ( 42 , S 145 , S 147 , S 163 , S 165 , S 169 ) changes the display state of the figure displayed on the display portion when it is detected that the game proceeding is shifted to the predetermined state (“YES” in the steps S 161 , S 167 , S 197 ). Accordingly, the operation effective area setting means ( 42 , S 171 ) sets the display area of the figure changed by the figure display state changing means as the operation effective area. Thus, it is possible to change the display state of the figure according to the game proceeding. In another aspect of this invention, a figure function setting means for setting a function of the figure, a figure function displaying means for displaying the function set by the figure function setting means in association with the figure, and a figure function changing means for changing the function set by the figure function setting means when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means are further provided, and the figure display state changing means changes in a displaying manner from the function displayed by the figure function displaying means to the function changed by the figure function changing means. More specifically, the figure function setting means ( 42 , S 43 , S 45 , S 47 ) sets the function of the figure. The figure function displaying means ( 42 , S 147 ) displays in association with the figure the function set by the figure function setting means. The figure function changing means ( 42 , S 163 ) changes the function set to the figure when it is detected that the game proceeding is shifted to a predetermined state by the game proceeding detecting means (“YES” in the step S 161 ). The figure display state changing means ( 42 , S 163 , S 165 ) changes in a displaying manner from the function of the figure to the modified function. Thus, it is possible to change the function of the figure according to the game proceeding, capable of displaying the figure with the function required for the game state at that time. In one embodiment of this invention, the figure display state changing means displays a new figure on the display portion when the game proceeding is shifted to a predetermined state by the game proceeding detecting means, and the operation effective area setting means sets a display area of the figure newly displayed as an operation effective area. More specifically, when it is detected that the game proceeding is shifted to the predetermined state (“YES” in the S 167 ), the figure display state changing means ( 42 , S 169 ) displays a new figure on the display portion ( 14 ). Accordingly, the operation effective area setting means ( 42 , S 171 ) sets the display area of the figure newly displayed as the operation effective area. Thus, it is possible to display a new figure in correspondence with the game proceeding, capable of increasing figures in correspondence with the game proceeding. In another aspect of this invention, a character selecting means for selecting an arbitrary character out of a plurality of kinds of characters is further provided, and the figure position setting means sets the figure at an arbitrary position of the display portion for each character selected by the character selecting means, and the game proceeding detecting means detects whether or not the character selected by the character selecting means is changed, the figure display state detecting means, when the character is changed by the game proceeding detecting means, changes the position of the figure to the figure position set to the changed character, and the operation effective area setting means sets the display area of the figure changed by the figure display state changing means as an operation effective area. More specifically, the character selecting means ( 42 , S 143 ) selects the arbitrary character out of the plurality of kinds of characters. The figure setting means ( 42 , S 145 , S 147 ) sets the figure at an arbitrary position of the display portion ( 14 ) for each character, the game proceeding detecting means ( 42 , S 197 ) detects whether or not the character selected by the character selecting means ( 42 , S 143 ) is changed. The figure display state detecting means ( 42 , S 145 , S 147 ), when the character is changed, changes the position of the figure to the figure position set to the changed character. Then, the operation effective area setting means ( 42 , S 145 ) sets the changed display area of the figure as an operation effective area. Accordingly, it is possible to set the display position of the figure for each plurality of kinds of characters, and when the character is modified, the figure can be changed to the display position set to the changed character, capable of setting the figure to an operable position for each character. In one embodiment of this invention, a pointing device is a touch panel provided in association with the display portion, and the operation effective area setting means sets an area of the touch panel corresponding to the display area of the figure as an operation effective area. More specifically, the pointing device is the touch panel ( 22 ) provided in association with the display portion ( 14 ). The operation effective area setting means ( 42 , S 41 , S 331 ) sets the area of the touch panel ( 22 ) corresponding to the display area of the figure as the operation effective area. Thus, the touch panel is utilized as a pointing device, capable of performing an intuitive operation. A game apparatus utilizing another pointing device according to this invention comprises a first display portion, a second display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, and a game processing means. The first display portion displays. a game image. The second display portion is arranged in proximity to the first display portion, and displays one or more figures to be operated by the player. The figure position setting means sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means changes a game image displayed on at least the first display portion in response to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The another game apparatus is approximately the same as the above-described game apparatus of this invention, and the game image is displayed on the first display portion ( 12 ), and in proximity thereto, the image to be operated by the player is displayed on the second display portion ( 14 ). In the other invention also, similarly to the above-described invention, it is possible to freely set the figure at an arbitrary position on the screen, capable of setting the figure at an operable position for each player. That is, it is possible to improve operability. A game apparatus utilizing the other pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, a game processing means, an operation state detecting means, and an operation effective area changing means. The display portion displays at least one or more figures. The figure position setting means sets the figure at a predetermined position of the display portion. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The operation state detecting means detects an operation state of the figure by the player. The operation effective area changing means changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting means. More specifically, the game apparatus ( 10 ) is provided with the display portion ( 14 ) for displaying one or more figures to be operated by the player. For example, the pointing device ( 22 ) is provided in association with the display portion ( 14 ). The figure position setting means ( 42 , S 37 ) sets the figure at the predetermined position of the display portion. The operation effective area setting means ( 42 , S 41 ) sets the display area of the figure set by the figure position setting means as the operation effective area. The operation coordinates position detecting means ( 42 , S 153 ) detects the operation coordinates position on the basis of the operation information detected by the operation of the pointing device ( 22 ). The operation coordinates position determining means ( 42 , S 155 ) determines whether or not the operation coordinates position detected by the operation coordinates position detecting means ( 42 , S 153 ) is within the operation effective area. The game processing means ( 42 , S 157 ) executes the game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means ( 42 , S 155 ). That is, the game process according to the function (command) set to the button is executed. The operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′) detects the operation state of the figure by the player. Then, the operation effective area changing means ( 42 , S 189 , S 195 , S 233 , S 233 ′, S 233 ″, S 237 , S 237 ′) changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting means( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′). According to the present invention, the operation effective area of the figure can be modified according to the operation state of the displayed figure, and therefore, the position of the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player. Thus, it is possible to improve operability. In one aspect of this invention, a figure display area changing means for changing the display area of the figure on the basis of the operation state detected by the operation state detecting means is further provided. More specifically, the figure display area changing means ( 42 , S 187 , S 193 , S 235 , S 235 ′, S 235 ″, S 239 , S 239 ′) changes the display area of the figure on the basis of the operation state detected by the operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 221 ′, S 229 , S 229 ′). That is, the display area of the figure is also changed according to the operation state by the payer, and thus, it is possible to easily inform the player that the position of the operation effective area is changed. In another aspect of this invention, a representative coordinates position extracting means for extracting a representative coordinates position out of a plurality of operation coordinates positions detected by the operation coordinates position detecting means is further provided. The operation effective area changing means changes a position of the operation effective area of the figure on the basis of the representative coordinates position extracted by the representative coordinates position extracting means. More specifically, the representative coordinates position extracting means ( 42 , S 229 ′) extracts the representative coordinates position out of the plurality of operation coordinates positions detected by the operation coordinates position detecting means ( 42 , S 221 ′). The operation effective area changing means ( 42 , S 233 ″, S 237 ) changes the position of the operation effective area of the figure on the basis of the representative coordinates position extracted by the representative coordinates position extracting means ( 42 , S 229 ′). Thus, the position of the operation effective area of the figure is changed to the representative coordinates position according to the operation state of the player, and therefore, the operation effective area can be corrected to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In one embodiment of this invention, the representative coordinates position extracting means extracts an operation coordinates position being the greatest in number out of the plurality of operation coordinates positions as the representative coordinates position. More specifically, the representative coordinates position extracting means ( 42 , S 229 ′) extracts the operation coordinates position being the greatest in number out of the plurality of operation coordinates positions, that is, the operation coordinates position being the highest in frequency of operation as the representative coordinates position. It is noted that an average value of a plurality of operation coordinates positions is calculated, and the operation coordinates position indicated by the calculated average value may be extracted as the representative coordinates position. Thus, the operation effective area is changed to the operation coordinates position being the highest in frequency of usage, and therefore, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player. In another aspect of this invention, the operation state detecting means detects the difference between a central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means, and the operation effective area changing means changes a position of the operation effective area of the figure on the basis of the difference. More specifically, the operation state detecting means ( 42 , S 159 , S 185 , S 191 , S 221 , S 229 ) detects the difference between the central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means ( 42 , S 153 ), and the operation effective area changing means ( 42 , S 189 , S 195 , S 233 , S 233 ′, S 237 , S 237 ′) changes the position of the operation effective area of the figure on the basis of the difference. That is, the position of the operation effective area of the figure is changed on the basis of the difference between the central position of the figure and the operation coordinates position detected by the operation of the player, and therefore, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In one embodiment of this invention, the operation effective area changing means changes the positions of the operation effective areas as to all figures displayed on the display portion on the basis of the difference. More specifically, the operation effective area changing means ( 42 , S 189 , S 195 , S 233 , S 237 ) changes the positions of the operation effective areas as to all the figures displayed on the display portion on the basis of the difference. Thus, the positions of the operation effective areas of all the figures are changed on the basis of the difference between the central position of the figure and the operation coordinates position detected by the operation of the player, and therefore, it is possible to reduce a processing load for changing the position of the operation effective area. In another embodiment of this invention, an average value calculating means for calculating an average value of differences detected by the operation state detecting means every operation of the figure is further provided, and the operation effective area changing means changes the position of the operation effective area of the figure on the basis of the average value calculated by the average value calculating means. More specifically, the average value calculating means ( 42 , S 229 ) calculates the average value of the differences detected by the operation state detecting means ( 42 , S 221 ) every operation of the figure. The operation effective area changing means ( 42 , S 189 , S 195 , S 233 , S 237 ) changes the position of the operation effective area of the figure on the basis of the average value calculated by the average value calculating means ( 42 , S 229 ). That is, the position of the operation effective area of the figure can be changed on the basis of the average value of the differences detected by the central position of the figure and a plurality of number of times of operations by the player, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In the other aspect of this invention, the operation state detecting means detects the number of times of operations of the figure, and the operation effective area changing means changes a size of the operation effective area of the figure on the basis of the number of times of operations. More specifically, the operation state detecting means ( 42 , S 159 ) detects the number of times of operations of the figure. The operation effective area changing means ( 42 , S 189 , S 195 ) changes the size of the operation effective area of the figure on the basis of the number of times of operations. Thus, the operation effective area of the figure can be changed to an adequate size according to the number of times of operations, capable of improving operability. The game apparatus utilizing another pointing device according to this invention comprises a display portion, a figure position setting means, an operation effective area setting means, an operation coordinates position detecting means, an operation coordinates position determining means, a game processing means, an operation state detecting means, and a figure display area changing means. The display portion displays one or more figures to be operated by the player. The figure position setting means sets the figure at a predetermined position of the display portion. The operation effective area setting means sets a display area of the figure set by the figure position setting means as an operation effective area. The operation coordinates position detecting means detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining means determines whether or not the operation coordinates position detected by the operation coordinates position detecting means is within the operation effective area. The game processing means executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining means. The operation state detecting means detects an operation state of the figure by the player. Then, the figure display area changing means changes the display area of the figure on the basis of the operation state detected by the operation state detecting means. In the other game apparatus, the display area of the figure is modified accord to the display state of the figure dissimilar to the above-described invention. According to this invention, the display area of the figure is modified according to an operation pattern, habit, frequency etc. of the figure by the player, and this leads the player to surely operate the position within the operation effective area, capable of improving operability. In one aspect of this invention, the figure display area changing means for changing the operation effective area of the figure in correspondence to the display area of the figure changed by the figure display area changing means is further provided. More specifically, the operation effective area changing means ( 42 , S 189 , S 195 , S 233 , S 237 ) modifies the operation effective area of the figure changed by the figure display area changing means ( 42 , S 187 , S 193 , S 235 , S 235 ′, S 235 ″, S 239 ′, S 239 ″). That is, the operation effective area of the figure is modified according to an operation pattern, habit, frequency etc. of the figure by the player, capable of improving operability. Also, it is possible to inform the player that the operation effective area of the figure is modified. In one embodiment of this invention, the operation state detecting means detects a difference between a central coordinates position of the figure and the operation coordinates position detected by the operation coordinates position detecting means, and the figure display area changing means changes a position of the display area of the figure on the basis of the difference. In this invention also, similarly to the above-described invention, it is possible to correct the operation effective area to an adequate position according to an operation pattern, habit, etc. by the player, capable of improving operability. In another embodiment of this invention, the operation state detecting means detects the number of times of operations of the figure, and the figure display area changing means changes a size of the display area of the figure on the basis of the number of times of operations. In this invention also, similarly to the above-described invention, the operation effective area of the figure can be changed to an adequate size according to the number of times of operations, capable of improving operability. In the other embodiment of this invention, the figure display area changing means reduces the display area of the figure when the number of times of operations is equal to or less than a first setting number of times, and enlarges the display area of the figure when the number of times of operations is equal to or more than a second setting number of times. More specifically, the figure display area changing means ( 42 , S 187 , S 193 ) reduces the display area of the figure when the number of times of operations is equal to or less than the first setting number of times (“YES” in the S 185 ), and enlarges the display area of the figure when the number of times of operations is equal to or more than the second setting number of times (“YES” in the S 191 ). That is, the figure being a low frequency of usage is displayed in a reduced manner, and the figure being a high frequency of usage is displayed in an enlarged manner, and therefore, the figure not frequently utilized is displayed so as to makes it difficult to operate, and the figure frequently operated is displayed so as to make it easy to operate. In a further embodiment of this invention, the figure display area changing means enlarges the display area of the figure when the number of times of operations is equal to or less than a first setting number of times, and reduces the display area of the figure when the number of times of operations is equal to or more than a second setting number of times. More specifically, contrary to the above-described other embodiment, when the number of times of operations of the figure is equal to or less than the first setting number of times, the figure is displayed in an enlarged manner, and when the number of times of operations is equal to or more than the second setting number of times, the display area of the figure is reduced. That is, the figure being a low frequency of usage is displayed in an enlarged manner, and the figure being a high frequency of usage is displayed in a reduced manner, and therefore, a difficulty level of the game operation can be increased, capable of preventing reduction in an interest to the game play. In another embodiment of this invention, the figure display area changing means erases the display area of the figure when the number of times of operations is equal to or less than a third setting number of times. More specifically, the display area of the figure being a low frequency of usage, that is, having the number of times of operations being equal to or less than the third setting number of times is erased. That is, the figure being a low frequency of usage is erased, and therefore, it is possible to make it impossible to use the figure not frequently utilized. In a storage medium storing a game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus comprises a display portion for displaying one or more figures to be operated by the player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, and a game processing step. The figure position setting step sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. Then, the game processing step executes a game process corresponding to the operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. In the storage medium storing the game program of this invention, similalry to the above-described invention of the game apparatus, it is possible to freely set the figure at an arbitrary position of the screen, and therefore it is possible to set the figure at an operable position for each player. In a storage medium storing another game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a first display portion for displaying a game image and a second display portion arranged in proximity to the first display portion for displaying at least one or more figures to be operated by a player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, and a game processing step. The figure position setting step sets the figure at an arbitrary position of the display portion on the basis of an instruction from the player. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. Then, the game processing step changes a game image displayed on at least the first display portion in response to an operation of the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. In the storage medium of this invention also, similarly to the above-described invention of the game apparatus, it is possible to freely set the figure at an arbitrary position of the screen, and therefore it is possible to set the figure at an operable position for each player. That is, operability is improved. In a storage medium storing the other game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a display portion for displaying at least one or more figures. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, a game processing step, an operation state detecting step, and an operation effective area changing step. The figure position setting step sets the figure at a predetermined position of the display portion. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. The game processing step executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. The operation state detecting step detects an operation state of the figure by the player. Then, the operation effective area changing step changes at least the operation effective area of the figure on the basis of the operation state detected by the operation state detecting step. In the storage medium of this invention also, similalry to the above-described invention of the game apparatus, the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player, capable of improving operability. In a storage medium storing another game program according to this invention, the game program is executed by a game apparatus utilizing a pointing device. The game apparatus is provided with a display portion for displaying one or more figures to be operated by the player. The game program causes the processor of the game apparatus to execute a figure position setting step, an operation effective area setting step, an operation coordinates position detecting step, an operation coordinates position determining step, a game processing step, an operation state detecting step, and a figure display area changing step. The figure position setting step sets the figure at a predetermined position of the display portion. The operation effective area setting step sets a display area of the figure set by the figure position setting step as an operation effective area. The operation coordinates position detecting step detects an operation coordinates position on the basis of operation information detected by an operation of the pointing device. The operation coordinates position determining step determines whether or not the operation coordinates position detected by the operation coordinates position detecting step is within the operation effective area. The game processing step executes a game process corresponding to the figure when it is determined to be within the operation effective area by the operation coordinates position determining step. The operation state detecting step detects an operation state of the figure by the player. The figure display area changing step changes the display area of the figure on the basis of the operation state detected by the operation state detecting step. In the storage medium according to this invention, similalry to the above-described invention of the game apparatus, the position of the display area and the operation effective area can be changed according to an operation pattern, habit, frequency, etc. of the figure by the player, capable of improving operability. Also, it is possible to easily inform the player that the operation effective area of the figure is modified. The above described objects and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. | 20050121 | 20110517 | 20051013 | 93769.0 | 0 | KIM, KEVIN Y | GAME APPARATUS AND STORAGE MEDIUM STORING GAME PROGRAM | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,038,880 | ACCEPTED | Inductor coil and method for making same | A high current, low profile inductor includes a conductor coil surrounded by magnetic material to form an inductor body. The inductor coil is formed from a flat plate which is cut into a sine-shaped configuration and then is folded in accordion fashion to create a helical coil. | 1-37. (canceled) 38. A method for making an inductor comprising: forming an inductor element having first and second inductor ends from an electrically conductive material; creating first and second terminal ends for the inductor element either by attaching the first and second terminal ends to first and second inductor ends of the inductor element or by forming the first and second terminal ends from the first and second inductor ends of the inductor element; making a mixture comprising a resin and a non-ferrite powdered magnetic material; compressing the mixture of resin and powdered magnetic material without liquefying the resin tightly around the inductor element to create an inductor body; the compressing step being accomplished without injection molding; leaving the first and second terminal ends outside the inductor body during the compressing step. 39. An inductor comprising: an inductor element of electrically conductive material having first and second inductor ends; first and second terminal ends either attached to the first and second inductor ends of the inductor element or being formed from the first and second inductor ends of the inductor element; an inductor body formed from a mixture of resin and non-ferrite powdered magnetic material that is compressed without injection molding and without liquefying the resin; and the first and second terminal ends being outside the inductor body. 40. The inductor of claim 39 wherein the inductor element is in the form of a coil including a coil center, the coil body comprising a single body formed from the compressed mixture of resin and non-ferrite powdered magnetic material, the coil body extending and contacting the coil both inside and outside the coil center. | BACKGROUND OF THE INVENTION The present invention relates to an inductor coil structure and method for making same. The coil structure of the present invention is preferably for use in a high current low profile inductor commonly referred to by the designation IHLP. However, the particular coil structure may be used in other types of inductors. Inductor coils have in the prior art been constructed from various shapes of materials formed into various helical shapes. However, there is a need for an improved inductor coil structure which is simple to manufacture and which provides an efficient and reliable inductance coil. Therefore, a primary object of the present invention is the provision of an improved inductor coil structure and method for making same. A further object of the present invention is the provision of an inductor coil structure which can be used in a high current low profile inductor having no air spaces in the inductor, and which includes a magnetic material completely surrounding the coil. A further object of the present invention is the provision of an inductor coil structure which includes a closed magnetic system which has self-shielding capability. A further object of the present invention is the provision of an inductor coil structure which maximizes the utilization of space needed for a given inductance performance so that the inductor can be of a minimum size. A further object of the present invention is the provision of an improved inductor coil structure which is smaller, less expensive to manufacture, and is capable of accepting more current without saturation than previous inductor coil structures. A further object of the present invention is the provision of an inductor coil structure which lowers the series resistance of the inductor. SUMMARY OF THE INVENTION The foregoing objects may be achieved by a high current low profile inductor comprising a conductor coil having first and second coil ends. A magnetic material surrounds the conductor coil to form an inductor body. The inductor coil comprises a plurality of coil turns extending around a longitudinal coil axis in an approximately helical path which progresses axially along the coil axis. The coil turns are formed from a flat plate having first and second opposite flat surfaces, at least a portion of each of the flat surfaces of the coil turns facing in a axial direction with respect to the coil axis. The method for making the inductor includes taking an elongated plate conductor having a first end, a second end, opposite side edges, opposite flat surfaces, and a longitudinal plate axis. A plurality of slots are cut in each of the opposite side edges of the plate conductor so as to form the plate conductor into a plurality of cross segments extending transversely with respect to the plate axis and a plurality of connecting segments extending approximately axially with respect to the plate axis. The connecting segments connect the cross segments together into a continuous conductor which extends in a sine shaped path. As used herein the term “sine shaped” refers to any shape which generally conforms to a sine curve, but which is not limited to a continuous curve and may include apexes, squared off corners or other various shapes. After cutting the slots in the opposite side edges of the plate conductor the connecting segments are bent along one or more bend axes extending transversely with respect to the plate axis so as to form the plate conductor into a plurality of accordion folds, each of which comprise one of the cross segments and a portion of one of the connecting segments. In the resulting structure, the cross segments and the connecting segments form a continuous conductor coil of approximate helical shape having first and second opposite ends. BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS FIG. 1 is a perspective view of the inductor constructed in accordance with the present invention and mounted upon a circuit board. FIG. 2 is a pictorial view of the coil of the inductor before the molding process. FIG. 3 is a pictorial view of the inductor of the present invention after the molding process is complete, but before the leads have been formed. FIG. 4 is an end elevational view taken along line 4-4 of FIG. 2. FIG. 5 is an elevational view taken along lines 5-5 of FIG. 4. FIG. 6 is a perspective view of an elongated conductor blank from which the inductor coil is formed. FIG. 7 shows the blank of FIG. 6 after the formation of slots extending inwardly from the opposite edges thereof. FIG. 8 is a view similar to FIG. 7, showing the first folding step in the formation of the inductor coil of the present invention. FIG. 9 is a side elevational view showing the same folding step shown in FIG. 8. FIG. 10 is a view similar to 8 and showing a second folding step in the process for making the inductor coil of the present invention. FIG. 11 is an inverted pictorial view of the inductor after it has been pressed, but before the leads have been formed. FIG. 12 is a view similar to FIG. 11 showing the inductor after partial forming of the leads. FIG. 13 is a view similar to FIGS. 11 and 12 showing the final forming of the leads. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings the numeral 10 generally designates an inductor of the present invention mounted upon a circuit board 12. Inductor 10 includes an inductor body 14 having a first lead 16 and a second lead 18 extending therefrom and being folded over the opposite ends of body 14. Leads 16, 18 are soldered or otherwise electrically connected on the circuit board 12. Referring to FIG. 2, the inductor coil of the present invention is generally designated by the numeral 20. Leads 16, 18 form the ends of coil 22. Between leads 16, 18 are a plurality of L-shaped coil segments 26 each comprising a horizontal leg 28 and a vertical leg 30. Vertical leg 30 terminates at a connecting segment 32 which is folded over at approximately 180° so as to create an accordion like configuration for inductor coil 20. The L-shaped coil segments are connected together to form a helical coil having an open coil center 34 extending along a longitudinal coil axis 36. FIGS. 6-10 show the process for making the coil 20. Initially as shown in FIG. 6 a blank flat conductor plate 50 formed of copper or other electrically conductive material includes: first and second ends 52, 54; a pair of opposite flat surfaces 56; and a pair of opposite side edges 58, 60. FIG. 7 shows the first step in forming the coil 20. In this step a plurality of slots 62, 64 are cut in the opposite edges 58, 60 respectively of the blank flat plate 50. Various cutting methods may be used such as stamping or actual cutting by laser or other cutting tools known in the art. Upon completion of the cutting operation, the blank 50 is transformed into an elongated sine shaped body formed from a plurality of cross segments 66 extending transversely to the longitudinal axis of plate 50 and a plurality of connecting segments 67 extending axially with respect to the longitudinal axis of plate 50. The segments 66, 67 form a continuous sine shaped configuration as shown in FIG. 7. FIG. 8 shows the next step in forming the coil 20. The end 52 is folded over at an angle of 180° to form the 180° angle bend 63 in the first connecting segment 67. FIG. 10 shows a second bend 65 which is in the next connecting segment 67. Bends 63, 65 are in opposite directions, and are repeated until an accordion like structure is provided similar to that shown in FIG. 5. In FIG. 5 the coil 20 includes opposite ends 16, 18 which are formed from the opposite ends 52, 54 of blank 50. The cross segments 66 of blank 50 form the first horizontal legs 28 of coil 20, and the connecting segments 67 of blank 50 form the second vertical legs 30 and the connecting segments 32 of coil 20. An example of a preferred material for coil 20 is a copper flat plate made from OFHC copper 102, 99.95% pure. The magnetic molding material of body 14 is comprised of a powdered iron, a filler, a resin, and a lubricant. The preferred powdered material is manufactured by BASF Corporation, 100 Cherryhill Road, Parsippany, N.J. under the trade designation Carbonyl Iron, Grade SQ. This SQ material is insulated with 0.875% mass fraction with 75% H3PO4. An epoxy resin is also added to the mixture, and the preferred resin for this purpose is manufactured by Morton International, Post Office Box 15240, Reading, Pa. under the trade designation Corvel Black, Number 10-7086. In addition a lubricant is added to the mixture. The lubricant is a zinc stearate manufactured by Witco Corporation, Box 45296, Huston, Tex. under the product designation Lubrazinc W. Various combinations of the above ingredients may be mixed together, but the preferred mixture is as follows: 1,000 grams of the powdered iron. 3.3% by weight of the resin. 0.3% by weight of the lubricant. The above materials (other than the lubricant) are mixed together and then acetone is added to wet the material to a mud-like consistency. The material is then permitted to dry and is screened to a particle size of −50 mesh. The lubricant is then added to complete the material 82. The material 82 is then ready for pressure molding. The next step in the process involves compressing the material completely around the coil 20 so that it has a density produced by exposure to pressure of from 15 to 25 tons per square inch. This causes the powdered material 82 to be compressed and molded tightly completely around the coil so as to form the inductor body 14 shown in FIG. 1 and in FIGS. 11-13. At this stage of the production the molded assembly is in the form which is shown in FIG. 11. After baking, the leads 16, 18 are formed or bent as shown in FIGS. 12 and 13. The molded assemblies are then baked at 325° F. for one hour and forty-five minutes to set the resin. When compared to other inductive components the IHLP inductor of the present invention has several unique attributes. The conductive coil, lead frame, magnetic core material, and protective enclosure are molded as a single integral low profile unitized body that has termination leads suitable for surface mounting. The construction allows for maximum utilization of available space for magnetic performance and is magnetically self-shielding. The unitary construction eliminates the need for two core halves as was the case with prior art E cores or other core shapes, and also eliminates the associated assembly labor. The unique conductor winding of the present invention allows for high current operation and also optimizes magnetic parameters within the inductor's footprint. The manufacturing process of the present invention provides a low cost, high performance package without the dependence on expensive, tight tolerance core materials and special winding techniques. The magnetic core material has high resistivity (exceeding 3 mega ohms) that enables the inductor as it is manufactured to perform without a conductive path between the surface mount leads. The magnetic material also allows efficient operation up to 1 MHz. The inductor package performance yields a low DC resistance to inductance ratio of two milliOhms per microHenry. A ratio of 5 or below is considered very good. The unique configuration of the coil 20 reduces its cost of manufacture. Coil 20 may be used in various inductor configurations other than IHLP inductors. In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to an inductor coil structure and method for making same. The coil structure of the present invention is preferably for use in a high current low profile inductor commonly referred to by the designation IHLP. However, the particular coil structure may be used in other types of inductors. Inductor coils have in the prior art been constructed from various shapes of materials formed into various helical shapes. However, there is a need for an improved inductor coil structure which is simple to manufacture and which provides an efficient and reliable inductance coil. Therefore, a primary object of the present invention is the provision of an improved inductor coil structure and method for making same. A further object of the present invention is the provision of an inductor coil structure which can be used in a high current low profile inductor having no air spaces in the inductor, and which includes a magnetic material completely surrounding the coil. A further object of the present invention is the provision of an inductor coil structure which includes a closed magnetic system which has self-shielding capability. A further object of the present invention is the provision of an inductor coil structure which maximizes the utilization of space needed for a given inductance performance so that the inductor can be of a minimum size. A further object of the present invention is the provision of an improved inductor coil structure which is smaller, less expensive to manufacture, and is capable of accepting more current without saturation than previous inductor coil structures. A further object of the present invention is the provision of an inductor coil structure which lowers the series resistance of the inductor. | <SOH> SUMMARY OF THE INVENTION <EOH>The foregoing objects may be achieved by a high current low profile inductor comprising a conductor coil having first and second coil ends. A magnetic material surrounds the conductor coil to form an inductor body. The inductor coil comprises a plurality of coil turns extending around a longitudinal coil axis in an approximately helical path which progresses axially along the coil axis. The coil turns are formed from a flat plate having first and second opposite flat surfaces, at least a portion of each of the flat surfaces of the coil turns facing in a axial direction with respect to the coil axis. The method for making the inductor includes taking an elongated plate conductor having a first end, a second end, opposite side edges, opposite flat surfaces, and a longitudinal plate axis. A plurality of slots are cut in each of the opposite side edges of the plate conductor so as to form the plate conductor into a plurality of cross segments extending transversely with respect to the plate axis and a plurality of connecting segments extending approximately axially with respect to the plate axis. The connecting segments connect the cross segments together into a continuous conductor which extends in a sine shaped path. As used herein the term “sine shaped” refers to any shape which generally conforms to a sine curve, but which is not limited to a continuous curve and may include apexes, squared off corners or other various shapes. After cutting the slots in the opposite side edges of the plate conductor the connecting segments are bent along one or more bend axes extending transversely with respect to the plate axis so as to form the plate conductor into a plurality of accordion folds, each of which comprise one of the cross segments and a portion of one of the connecting segments. In the resulting structure, the cross segments and the connecting segments form a continuous conductor coil of approximate helical shape having first and second opposite ends. | 20050120 | 20060425 | 20050609 | 57822.0 | 6 | NGUYEN, TUYEN T | INDUCTOR COIL AND METHOD FOR MAKING SAME | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,038,956 | ACCEPTED | Ligands directed to the non-secretory component, non-stalk region of pIgR and methods of use thereof | The invention provides compositions and methods for specific binding to a region of the polymeric immunoglobulin receptor (pIgR) of a cell with the provisos that the ligand does not substantially bind to the most abundant form of the secretory component (SC) of pIgR present in an organ of interest of an animal of interest under physiological conditions, and does not bind to the pIgR stalk. In some embodiments, the ligand decreases cleavage of SC from the stalk by at least one-third. The ligands and methods of the invention can be used with both birds and mammals. In more preferred embodiments, the animal is a mammal. In the most preferred embodiment, the animal is a human. The ligand may be targeted into the cell or may undergo retrograde transcytosis and release at the basolateral side of the cell, and may comprise a biologically active composition. | 1. A method of introducing a ligand into a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor, by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. 2. A method of claim 1, wherein the ligand is an antibody. 3. A method of claim 1, wherein the ligand is a humanized antibody. 4. A method of claim 1, wherein the ligand is selected from the group consisting of a recombinant single chain variable region fragment of an antibody and a disulfide stabilized variable region fragment. 5. A method of claim 1, wherein the ligand forms the binding portion of an immunoconjugate further comprising an effector moiety. 6. A method of claim 5, wherein the effector moiety is a nucleic acid which encodes the wildtype cystic fibrosis transmembrane conductance regulator. 7. A method of claim 5, wherein the effector moiety is selected from the group consisting of a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. 8. A method of claim 5, wherein the effector moiety is a therapeutic agent. 9. A method of claim 1, wherein the cell is a mammalian cell. 10. A method of claim 9, wherein the cell is an epithelial cell. 11. A method of claim 1, wherein the organ of interest is selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. 12. A method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. 13. A method of claim 12, wherein the ligand is an antibody. 14. A method of claim 13, wherein the ligand is a humanized antibody. 15. A method of claim 13, wherein the ligand is selected from the group consisting of a recombinant single chain variable region fragment of an antibody and a disulfide stabilized variable region fragment. 16. A method of claim 12 wherein the ligand is the binding component of an immunoconjugate further comprising an effector moiety. 17 A method of claim 16, wherein the effector moiety is selected from the group consisting of a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. 18. A method of claim 16, wherein the effector moiety is a therapeutic agent. 19. A method of claim 12, wherein the cell is a mammalian cell. 20. A method of claim 19, wherein the cell is an epithelial cell. 21. A method of claim 12, wherein the organ of interest is selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. 22. A method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by attaching the ligand to a region of the pIgR, provided that (a) binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby permitting transcytosis of the ligand from the apical side to the basolateral side of the cell. 23. A method of claim 22, wherein the ligand is an antibody. 24. A method of claim 23, wherein the ligand is a humanized antibody. 25. A method of claim 23, wherein the ligand is a scFv. 26. A method of claim 23, wherein the ligand is selected from the group consisting of a recombinant single chain variable region fragment of an antibody and a disulfide stabilized variable region. 27. A method of claim 22, wherein the ligand is the binding component of an immunoconjugate further comprising an effector moiety. 28. A method of claim 27, wherein said effector moiety is selected from the group consisting of: a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. 29. A method of claim 22, wherein the animal is a mammal. 30 A method of claim 22, wherein the cell is a mammalian cell. 31. A method of claim 30, wherein the cell is an epithelial cell. | CROSS-REFERENCES TO RELATED APPLICATIONS This application claims priority from U.S. Provisional Patent Application No. 60/192,197, filed Mar. 27, 2001, and U.S. Provisional Patent Application No. 60/192,198, filed Mar. 27, 2001. The contents of both applications are incorporated herein by reference. STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT This invention was made with government support under grant number A139161 awarded by the National Institute of Allergy and Infectious Diseases of the U.S. National Institutes of Health. The government has certain rights in the invention. FIELD OF THE INVENTION The present invention relates, in general, to compositions and methods for the specific binding of a ligand to a region of the polymeric immunoglobulin receptor (“pIgR”) which is not within the stalk nor in the most abundant species of the secretory component as it exists in an organ or on a tissue of interest, for internalization into, or transport across, a cell which secretes pIgR. BACKGROUND OF THE INVENTION One of the most challenging problems facing the pharmaceutical and biopharmaceutical industries is delivering therapeutic agents past the various semi-permeable membranes within the body. Particularly in the case of macromolecules, the obstacle to cost effective or convenient treatment is often due to the lack of an adequate drug delivery system. In turn, this issue dictates whether production of a drug is economically feasible. Thus, the search for alternative delivery systems often rivals the search for new drugs themselves. Gene transfer methods can be viewed as a paradigm of macromolecular drug delivery. These methods can be divided into three categories: physical (e.g., electroporation, direct gene transfer, and particle bombardment), chemical (e.g., proteinoids, microemulsions, and liposomes), and biological (e.g., virus-derived vectors, and receptor-mediated uptake). Among biological transfer methods, receptor-mediated uptake is a particularly promising approach. Targeting a ligand to an endocytosed receptor acts as a means to ferry that ligand into the cell. One drawback of receptor-mediated systems, however, has been their general reliance on intravenous administration, which severely limits their use. Mucosal epithelial cells line a number of readily accessible tissues such as those found in the upper respiratory and gastrointestinal tracts. The accessibility of these cells make them an attractive target for drug delivery. See, e.g., Ferkol et al., J. Clin. Invest. 92:2394-2400 (1993); Ferkol et al., J. Clin. Invest. 95:493-502 (1995). Retrograde transport of an antibody from the lumenal to the basolateral surface of epithelial cells has been reported, albeit at very low levels. Breitfeld et al., J. Cell Biol. 109:475-486 (1989). In that study, movement across the cell was followed by binding an antibody to the secretory component of polymeric immunoglobulin receptor (“pIgR”). Relative to the level of basolateral to apical transport, Breitfeld et al. reported that less than 5% of the transport was retrograde in nature. The nominal level of counter-transport minimizes the utility of secretory component as a means to deliver biologically active compositions into cells. Moreover, due to the abundance of cleaved pIgR in the lumen, binding of ligand to cleaved pIgR, rather than the intact pIgR of the cell surface, would diminish the utility of pIgR counter-transport as a mechanism of drug delivery. In commonly-assigned application Ser. No. 08/856,383, now U.S. Pat. No. 6,042,833, it was reported that a stalk remained on the surface of the cell following cleavage of the secretory component (“SC”). It was further found that ligands could be targeted to the stalk and thereafter undergo internalization and retrograde transport. As useful as this is, the stalk represents a limited target for ligands and it would be helpful to have additional targets for ligands which can be internalized and which are not diluted by binding in substantial amounts to cleaved pIgR. BRIEF SUMMARY OF THE INVENTION This invention provides ligands that bind specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell of an animal, which pIgR when cleaved has a stalk region which remains attached to the cell and a secretory component (SC) which exists in an organ of interest in several forms, provided that the ligands do not substantially bind to the most abundant form of SC present in the organ of interest and provided further that the ligands do not substantially bind to the stalk of said pIgR under physiological conditions. The ligands can bind to the pIgR of birds or of mammals. With regard to mammals, the ligands can bind to the pIgR of a mammal selected from the group consisting of pig, cow, horse, sheep, goat, cat, dog, and human. The ligands can be, for example, an antibody, a humanized antibody, a recombinant single chain variable region fragment of an antibody or a disulfide stabilized variable region fragment. In some preferred embodiments, the ligands bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some particularly preferred embodiments, the ligands bind to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The organ of interest may be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a salivary gland, a stomach, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The ligands may comprise a binding component for binding to pIgR and a biologically active component. In one set of embodiments, the biologically active component is a nucleic acid encoding the wildtype cystic fibrosis transmembrane conductance regulator. In other sets of embodiments, the biologically active component is selected from the group consisting of a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. In one set of embodiments, the invention provides ligands that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell of an animal, which pIgR has an initial cleavage site and which upon initial cleavage has a stalk region which remains attached to the cell and a secretory component (SC) which exists in an organ of interest in several forms, provided that the ligand does not substantially bind to the most abundant form of SC present in the organ of interest and provided further that the ligand does not substantially bind to a peptide comprising 31 amino acids that are cell-membrane-proximal to the initial cleavage site. In another group of embodiments, the invention provides a method of introducing a ligand into a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor, by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. In some of these embodiments, the ligand is an antibody, and may be a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region fragment, either of which may be humanized. The ligand can selectively bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some preferred embodiments, the ligand binds to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The method further encompasses embodiments wherein the ligand is further defined as having a binding component for selectively binding to pIgR and a biologically active component. The biologically active component may be a nucleic acid which encodes the wildtype cystic fibrosis transmembrane conductance regulator. In other embodiments, the biologically active component may be selected the group consisting of a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. The cell may be a mammalian cell, especially an epithelial cell. The organ of interest may be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. In another group of embodiments, the invention provides a method of introducing a ligand into a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), which pIgR has an initial cleavage site which, upon initial cleavage has a stalk region, the method comprising binding the ligand to a region of the pIgR, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions; (b) the ligand does not substantially bind to a stalk region of the pIgR; and (c) the ligand does not bind to an extracellular epitope within the first 31 amino acids that are cell membrane proximal to the initial cleavage site of the pIgR, thereby permitting introduction of the ligand into the cell. Yet another method provided by the invention is a method of increasing the rate by which a first ligand which binds to secretory component (SC) is internalized into a cell secreting a polymeric immunoglobulin receptor (pIgR) from an apical surface by (a) binding the pIgR with a second ligand, which second ligand inhibits proteolytic cleavage of SC by at least one-third, and further which second ligand does not substantially bind to a stalk remaining attached to the cell after proteolytic cleavage, and (b) binding the first ligand to the SC, thereby permitting internalization into said cell of the SC to which the first ligand is bound. The invention further provides ligands that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell, provided that binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of binding of the ligand and provided further that the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions. The ligand may be an antibody, a scFv, a recombinant single chain variable region fragment of an antibody, a disulfide stabilized variable region fragment (“dsFv”), a humanized scFv, or a humanized dsFv. The ligands may bind to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In one set of embodiments, the ligand binds to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The ligand may further be a binding component of a molecule comprising a biologically active component. In some embodiments, the biologically active component may be selected from the group consisting of: a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. In yet another, the biologically active component is a nucleic acid encoding the wildtype cystic fibrosis transmembrane conductance regulator. In yet another set of embodiments. the invention provides a conjugate, fusion protein, or complex, said conjugate fusion protein or complex comprising a ligand that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell and a biologically active component, provided that binding of the conjugate, fusion protein, or complex to pIgR reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of binding of the conjugate, fusion protein, or complex and provided further that the conjugate, fusion protein, or complex does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions. In another set of embodiments, the invention provides methods of introducing a ligand into a cell expressing a polymeric immunoglobulin receptor (pIgR) by attaching the ligand to a region of the pIgR, provided that (a) binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby permitting introduction of the ligand into the cell. The ligand may be, for example, an antibody, a humanized antibody, a scFv, a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region. The ligand preferably binds to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some embodiments, the ligand binds to an epitope of pIgR selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The ligand may have a binding component for selectively binding to a region of pIgR and a biologically active component. The biologically active component may be selected from the group consisting of: a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In one set of embodiments, the biologically active component is a small molecule. The animal can be a mammal. In one embodiment, the biologically active component is a nucleic acid encodes the wildtype cystic fibrosis transmembrane conductance regulator. The cell can be a mammalian cell, especially an epithelial cell. The ligand can bind to the pIgR at the apical surface of the cell. The ligand can then be transcytosed to the basolateral side of the cell, and may remain attached or can be released from the pIgR at the basolateral surface of the cell. The SC can exist in several forms in an organ of interest, provided that the ligand (a) does not bind to the most abundant form of SC present in the organ of interest, and (b) does not bind to a stalk remaining on an extracellular surface of a cell of the organ of interest after pIgR cleavage. The organ of interest can be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The invention further relates to methods of attaching a ligand to a cell expressing a polymeric immunoglobulin receptor comprising the step of binding the ligand to the receptor with the provisos that (a) the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby attaching the ligand to the cell. The method can permit the ligand to be internalized into the cell after binding. The invention also provides a method of attaching a conjugate, fusion protein, or complex to a cell expressing a polymeric immunoglobulin receptor, said conjugate, fusion protein, or complex comprising a ligand that binds to a region of pIgR and a biologically active component, said method comprising the step of binding the ligand to the receptor with the provisos that (a) the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby attaching the conjugate, fusion protein, or complex to the cell. The invention further provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. The ligand may be, for example, an antibody, a humanized antibody, a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region fragment. The ligand may selectively bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In one set of preferred embodiments, the ligand may bind to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). In some embodiments of the method, the ligand may further be defined as having a binding component for selectively binding to pIgR and a biologically active component. The biologically active component is selected from the group consisting of a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. In one set of embodiments, the biologically active component can be a small molecule. The method can be used with respect to a mammalian cell, and especially where the cell is an epithelial cell. The organ of interest can be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The invention further provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), which pIgR has an initial cleavage site which, upon initial cleavage has a stalk region, the method comprising binding the ligand to a region of the pIgR, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions; (b) the ligand does not substantially bind to a stalk region of the pIgR; and (c) the ligand does not bind to an extracellular epitope within the first 31 amino acids that are cell membrane proximal to the initial cleavage site of the pIgR, thereby permitting introduction of the ligand into the cell. The invention additionally provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by attaching the ligand to a region of the pIgR, provided that (a) binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby permitting transcytosis of the ligand from the apical side to the basolateral side of the cell. The ligand can be, for example, an antibody, including a humanized antibody, a scFv (including a recombinant single chain variable region fragment of an antibody), and a disulfide stabilized variable region. The ligand can bind to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some preferred embodiments, the ligand binds to an epitope of pIgR selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). In one group of embodiments of this method, the ligand is further defined as having a binding component for selectively binding to a region of pIgR and a biologically active component. The biologically active component can be a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. In one group of embodiments, the biologically active component is a small molecule. The animal can be a mammal, and the cell can be a mammalian cell, and preferably is an epithelial cell. The invention further provides a method of increasing the rate by which a first ligand which binds to secretory component (SC) is transcytosed from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR) from an apical surface by (a) binding the pIgR at the apical side of said cell with a second ligand, which second ligand inhibits proteolytic cleavage of SC by at least one-third, and further which second ligand does not substantially bind to a stalk remaining attached to the cell after proteolytic cleavage, and (b) binding the first ligand to the SC, thereby permitting transcytosis of the SC to which the first ligand has bound from the apical to the basolateral side of said cell. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1. FIG. 1 shows an alignment of the sequences of the human (SEQ ID NO:1), bovine (SEQ ID NO:2), rat (SEQ ID NO:3), mouse (SEQ ID NO:4), possum (SEQ ID NO:5), and rabbit (SEQ ID NO:6) pIgR, including a leader sequence (labeled “Leader peptide” in the Figure) which is not present in the mature pIgR molecule. Residues identical to those of the human sequence at the same location are shown as dashes, residues differing at a particular point are shown. Ends of domains are denoted by opposed arrows. Some of the cleavage sites for the secretory component suggested by the experimental evidence (see text) are marked by vertical arrows. The box in the top portion of the figure labeled “Ig-binding site” denotes the site at which IgA binds to pIgR and is not the intended target of the ligands discussed herein. The vertical arrow labeled “Bridge to IgA” designates a cysteine which forms a disulfide bond to IgA. Stars designate the cysteine residues. The opposed arrows to the left of the label “Transmembrane” denote the end of the transmembrane domain and the start of the extracellular portion of pIgR. The extracellular portion of pIgR closest to the transmembrane domain comprises the stalk. Note: as described in more detail in the text, the numbering of the residues of human pIgR in FIG. 1 does not include the 18 residue leader sequence counted in the numbering system used in the SWISS-PROT database and followed in the text. FIG. 2. FIG. 2 shows the sequence of human pIgR (SEQ ID NO:1) as set forth in the SWISS-PROT database under accession number P01833. The amino acids in the sequence are set forth in standard single-letter code. FIG. 3 FIG. 3 shows the results of experiments mapping the epitopes of pIgR recognized by various scFv antibodies from a human library. The lines marked “Human” set forth a portion of the amino acid sequence of human pIgR (the portion set forth is SEQ ID NO:17), encompassing part of domain 5 and all of domain 6. The sequences marked “Rat” set forth a corresponding portion of the amino acid sequence of rat pIgR (the portion set forth is SEQ ID NO:18). A further line sets forth the sequence of the human pIgR stalk (SEQ ID NO:19). The downward arrows denote the initial cleavage site of pIgR. The upward arrows denote various C termini of the SC of human colostrum found by Eiffert et al. or by Hughes et al. The shorter horizontal, double-ended arrow denotes the minimal colostrum B region, which is bounded by the initial pIgR cleavage site on the C terminal side, and by the C terminus found by Hughes et al. on the other. The longer horizontal, double-ended arrow denotes the maximal colostrum B region, bounded by the initial cleavage site on the C terminal side of the B region and by the most amino terminal residue found by Eiffert et al. on the other. It should be noted that other organs, such as the intestine, have more and greater concentrations of proteases, so the B region in those organs is expected to be bigger. The number and letter combinations, such as “4A,” denote particular scFvs. The shaded boxes show the epitopes to which the designated scFv bound. As shown, certain epitopes were bound by more than one scFv. FIG. 4 FIG. 4 shows the results of studies mapping the epitopes of pIgR recognized by polyclonal antibodies raised in a goat in response to immunizations with a fusion protein comprising a portion of rat pIgR. The lines labeled “Human” set forth a portion of the human pIgR sequence than used in FIG. 3 (the sequence in this Figure is SEQ ID NO:20). The line labeled “Rat” sets forth a portion of the rat pIgR sequence (the sequence used in this Figure is SEQ ID NO:21). The downward facing, upward facing and horizontal arrows are as described for FIG. 3. The shaded boxes show where the polyclonal antibodies bound in the mapping studies. FIG. 5 FIG. 5 shows the amino acid sequence (SEQ ID NO:22) of a secreted form of scFv 4A, bearing two labels: the FLAG® epitope and an epitope from the myc oncogene, as well as a six-histidine tail for easy purification. PelB leader: PelB leader promotes secretion of the peptide from E. coli. FLAG®: FLAG® epitope. Heavy chain FR: Framework region of immunoglobulin heavy chain. Light chain FR: Framework region of immunoglobulin light chain. CDR: complementarity determining region. Numbers after the abbreviations designate the particular numbered region, e.g., CDR3 designates complementarity determining region 3, which is considered in the art to have the greatest contact with the target epitope of the antigen. Linker: linker peptide used in 4A construct (GGGS=SEQ ID NO:23). myc: epitope from myc oncogene recognized by commercially available antibodies. 6 HIS: 6 histidine tail. DETAILED DESCRIPTION Introduction The present invention is directed to a ligand that binds specifically to a portion of a polymeric immunoglobulin receptor (pIgR) of a cell with the provisos that the ligand does not substantially bind to the most abundant species (or form) of the secretory component present in an animal tissue, organ, or lumen, or to the stalk remaining on the extracellular surface of the cell after pIgR is cleaved. The invention provides, inter alia, methods of attaching and introducing a ligand into a cell expressing pIgR. After transport to the apical surface of epithelial cells, the pIgR undergoes an initial cleavage and the secretory component (sometimes hereafter abbreviated as “SC”), comprising the bulk of the molecule, is released into the extracellular space, while a residual extracellular region of pIgR (the “stalk”) remains accessible on the cell surface. Newly-cleaved SC contains a carboxy-terminal region adjacent to the cleavage site which is rapidly degraded by proteases to provide the SC typically found in the lumenal space, such as the mammalian intestine. Hereafter, the region of the SC adjacent to the cleavage site which undergoes further proteolytic digestion or secondary cleavage following cleavage from intact pIgR is sometimes referred to as the “B region.” Since the B region is rapidly degraded, the most abundant form of the SC present in the extracellular space (for example, SC present in the animal intestine and, in particular, the mammalian small and large intestines) does not contain it. Hereafter, this processed SC is referred to interchangeably as the “most abundant form,” “most abundant species,” or “major species” of SC present in an organ of interest (such as in the lumen of the intestine or on the surface of the lung) or on a tissue of interest (such as on the surface of nasal or sinus passages, etc.) when the distinction from newly-cleaved, but as yet unprocessed, SC is necessary. In the intestinal tract, which has particularly high levels of proteases, some of the SC may undergo further proteolysis, but a substantial amount of the SC survives intestinal degradation and is excreted in the feces. While the level of proteases is highest in the intestines, proteases exist in the lumen of other organs and on mucosal surfaces. Thus, degradation of the B region is not limited to the intestinal tract. While rapid, the cleavage of the pIgR at the apical surface is not instantaneous. Thus, there exists a limited pool of uncleaved, intact pIgR at the cell surface. As the pIgR is cleaved and the SC undergoes rapid processing, however, the epitopes to which ligands directed to the B region bind are destroyed. This offers a surprising advantage to using ligands targeted to this region compared to ligands targeted to the remaining, much larger, portion of the SC. Because the epitopes to which ligands targeted to the B region are rapidly degraded after pIgR cleavage, a high proportion of ligands directed to the B region bind to intact pIgR and are available for internalization and transcytosis to the basolateral surface of the cell. In contrast, ligands directed to other portions of the SC will bind both to intact pIgR and to SC present in the extracellular space; thus, a markedly smaller proportion of such ligands will bind to intact pIgR than will ligands targeted to the B region. Since ligands bound to free SC do not internalize into a pIgR-expressing cell, these ligands will not be available to be transcytosed from the apical surface to the basolateral surface of the cell, and a correspondingly higher amount of such ligands will have to be introduced to accomplish transcytosis of a given amount of ligand to the basolateral surface. Thus, if retrograde transport of the ligand from the lumen to the basolateral side of a pIgR-expressing cell is desired, it is advantageous if the ligand binds to the B region rather than to portions of the SC not within the B region. This advantage of ligands targeted to the B region has not previously been recognized or exploited in the art. Even more advantageously, ligands can be directed specifically to the area of or around the initial cleavage site at which SC is severed from the stalk, thereby inhibiting cleavage of secreted pIgR. For example, ligands directed to this region can sterically block access of proteases to the cleavage site. A higher proportion of such ligands will be internalized into the pIgR-secreting cell compared to ligands which bind to areas of the SC on the N-terminal side of the B region, for two reasons. First, since the ligand prevents the pIgR from being cleaved, the intact pIgR is available to be reinternalized, along with the ligand. Second, ligands which inhibit cleavage are unlikely to bind to free SC since free SC is unlikely to have the epitope or other conformation recognized by a ligand which has this functionality. Thus, such ligands are especially advantageous. In some embodiments, the ligand itself may not be large enough to impede access of a protease to the initial pIgR cleavage site, but the ligand may be conjugated, fused, or complexed to another moiety (such as a peptide, nucleic acid, antibody, radioisotope, lipid, carbohydrate, small molecule, peptidomimetic, radioisotope, antibiotic, anti-infective, or the like), and the conjugate, fusion protein, or complex may be large enough to impede access by the protease. These conjugates, fusions, and complexes are also within the scope of the present invention. The ability of ligands or of conjugates, fusions, or complexes, to inhibit or block cleavage of the SC can be readily determined by assays determining the rate of SC cleavage in the presence and in the absence of the ligand, conjugate, fusion, or complex. A number of assays are known in the art; an exemplary assay, using a pulse-chase technique, is set forth in the Examples. The present invention has utility as a means of transporting therapeutic or diagnostic compositions to, into (endocytosis) or across (transcytosis) a cell expressing pIgR. Thus the invention can be used to transport biologically active compositions such as proteins, nucleic acids, or detectable labels specifically to cells expressing pIgR. The invention also provides a means of labeling and distinguishing epithelial cells from among a mixed cell population in pathology studies. Further, since pIgR expression is reduced in carcinomas relative to normal epithelium, the labeling of pIgR has utility as a diagnostic adjunct in endoscopic or radiologic procedures. Additionally, binding of therapeutic ligands to pIgR has utility in extending the duration of the ligands in the lumen of various passageways and increasing their effectiveness. The invention can be used in a number of contexts. pIgR is secreted on mucosal surfaces throughout the body, including the gastrointestinal tract, most if not all of the genito-urinary tract, the entire respiratory system, from nose and sinuses to the aveloli of the lung, and the lacrimal glands of the eye. Thus, the invention can be used, for example, to deliver agents to (a) the gastrointestinal tract, including the stomach, small intestine, or large intestine, through oral administration or endoscopic administration, (b) the mouth, and specifically the salivary glands, by, for example, cannulation of the glands, (c) the liver-biliary tree, by endoscopic retrograde cannulation of the pancreatic duct or bile duct (these are a common duct in most humans), (d) to the nose or sinuses, by nose drops or sprays, (e) to the lung, typically by inhalation of aerosolized mists (see, e.g., U.S. Pat. Nos. 5,960,792, 5,934,272, 5,906,202, and 5,622,162) or finely dispersible dry powders (see, e.g., U.S. Pat. Nos. 5,740,794, and 5,458,135), (f) to the vagina, by spray, douche, or suppository, (g) to the uterus, typically by spray, (h) to the anus, typically by suppository, (i) to the mammary gland, typically by cannulation, to treat infectious, hormonal, or other conditions, and, (j) to the eyes, and especially the conjunctiva, by eye drops or opthalmic ointments. These applications permit localized delivery of the therapeutic agent to an affected organ or tissue, often with higher concentrations than can be easily achieved with systemic administration. For example, a therapeutic agent can be delivered to the tissues surrounding the conjunctiva or lacrimal gland or associated structures and ducts in a person with an infectious or inflammatory eye condition by using eye drops incorporating the compositions of the invention. The ligands and methods of the invention can generally be used to deliver compositions to animals which express pIgR and in which a secretory component of pIgR is cleaved away, leaving a stalk. In some embodiments, for example, the invention is used in birds, which are known to express SC. The invention is especially useful for birds reared for human consumption, such as chickens, turkeys, ducks, and ostriches. These birds are raised commercially in flocks and the invention provides a new and convenient method of administering veterinary compositions to one or more members of a flock. The invention can also be used, however, with respect to individual birds, such as parrots, cockatiels, and macaws, being raised for sale or kept as pets, as well as to other birds, such as sea birds rescued from oil slicks, to which veterinary attention may be directed. In preferred embodiments, the invention is used to deliver compositions to mammals. In veterinary uses, the invention can be used as a means of administering therarpeutic compositions to pigs, sheep, goats, cows, dogs, cats, horses, and other farm and domestic animals. In one group of embodiments, the invention can be used to deliver therapeutic formulations to populations of wild animals, such as raccoons, foxes, bison, elk, rodents, and the like, to reduce the likelihood of their spreading disease to farm animals or human populations. In the most preferred embodiments, the invention is used to administer compositions of interest, such as therapeutic compositions, to humans. DEFINITIONS Unless defined otherwise herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Singleton et al. (1994) Dictionary of Microbiology and Molecular Biology, second edition, John Wiley and Sons (New York), and Hale and Marham (1991) The Harper Collins Dictionary of Biology, Harper Perennial, NY provide one of skill with a general dictionary of many of the terms used in this invention. Amino acids may be referred to herein by either their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission. Nucleotides, likewise, may be referred to by their commonly accepted single-letter codes. For purposes of the present invention, the following terms are defined below. By “pIgR” or “polymeric immunoglobulin receptor” is meant the receptor which is expressed in mucosal epithelial cells, including airway epithelial cells, submucosal gland cells, intestinal cells, nasal epithelium, breast, oral mucosa, urinary and reproductive tract epithelium, and conjunctival tissue, and is implicated in basolateral to apical transcytosis of dimeric immunoglobulin A (dIgA) and/or pentameric IgM. Both mammals and birds express pIgR. The nucleic acid and amino acid sequence of the polymeric immunoglobulin receptor has been identified in a variety of taxonomically diverse species. See, Piskurich et al., Journal of Immunology 154:1735-1747 (1995); the amino acid sequences for human pIgR (SEQ ID NO:1), bovine pIgR (SEQ ID NO:2), rat pIgR (SEQ ID NO:3), mouse pIgR (SEQ ID NO:4), possum pIgR (SEQ ID NO:5) and rabbit pIgR (SEQ ID NO:6) are set forth in FIG. 1. As explained in more detail below, the most common current numbering system for pIgR counts the leader sequence and therefore accords the residues a position 18 places higher than the numbers set forth for the same residues in FIG. 1. By “stalk” is meant the extracellular component of the polymeric immunoglobulin receptor (pIgR) that corresponds to that region of pIgR that is bound to the cell following cleavage of that segment of pIgR which constitutes the secretory component. The stalk is present regardless of whether the segment of pIgR which corresponds to secretory component is cleaved or uncleaved from pIgR. By “secretory component” or “SC” is meant that extracellular portion of pIgR which is generally cleaved following basolateral to apical transcytosis. Typically, the secretory component comprises the dimeric IgA (dIgA) binding portion of pIgR. Secretory component is typically released into the lumen with or without dIgA bound to the secretory component. The term “B region” refers to a portion of SC which undergoes rapid proteolytic digestion or secondary cleavages after cleavage of the SC from intact pIgR in an tissue of interest or organ of interest which secretes pIgR. The B region is therefore absent from the majority of free SC as it exists, for example, in the mammalian small and large intestines. The SC, and the proteolytic processes which result in the degradation of the “B region,” also occur in certain non-mammalian animals, such as birds. The term “B region” therefore further relates as appropriate to the portion of the SC of birds, such as chickens and turkeys, which rapidly degrades after cleavage of the SC. The terms “major species,” “most abundant species,” and “most abundant form” are generally used interchangeably herein and refer to the most abundant form of the SC in the organ of interest or on the tissue of interest of an animal species under consideration. For example, with respect to oral administration to the intestine of an animal, the terms refer to the most abundant form in the intestinal tract of the animal and, with reference to humans, refers to the most abundant form in the human intestinal tract. A “tissue of interest” refers to those tissues, such as those of the nasal cavity, the paranasal sinuses, and the lacrimal glands of the eyes, which secrete pIgR into adjacent fluids, such as mucus in the nasal passages in the case of the nasal cavity or tears on the conjunctiva in the case of the lacrimal glands, but which are not conveniently described as being part of a discrete organ. An “organ of interest” refers to an organ containing a lumen or other internal space (such as the interior surface of the lung or of the uterus) into which pIgR is secreted and to which a practitioner wishes to deliver ligands of the invention. Suitable organs include the organs of the gastrointestinal tract, the liver-biliary tree, the lungs, the vagina, and the uterus. References herein to the most abundant form of SC in the organ refer to the most abundant form of SC in the lumen or internal space of the organ. The distinction between a “tissue of interest” and an “organ of interest” is made herein for clarity in discussions relating to the definition of the major form of SC present. In a “tissue of interest,” the major form of the SC is that in the fluids (such as mucus or tear) on the surfaces around the pIgR-secreting cells. Thus, the major form of the SC in the nasal passages is the major form found in the mucus inside the nose. In an “organ of interest,” the major form of SC is that found within the lumen of the organ (such as the intestine) or in a internal space into which the organ (such as the uterus or vagina) secretes pIgR, and, in the case of organs in which the major form of the SC may be different at different sites (such as in the small intestine, where the number and concentration of proteases may be different in the duodenum and in the ileum), it generally means at the site of intended administration. Except where necessary for clarity, as used herein, the term “tissue of interest” is encompassed herein by the term “organ of interest.” By “ligand” or “ligand binding moiety”, is meant all molecules capable of specifically binding to the polymeric immunoglobulin receptor (pIgR). Ligands include, but are not limited to, antibodies, proteins, peptides, nucleic acids, lipids, and carbohydrates. As used herein, “antibody” includes reference to an immunoglobulin molecule immunologically reactive with a particular antigen, and includes both polyclonal and monoclonal antibodies. The term also includes genetically engineered forms such as chimeric antibodies (e.g., humanized murine antibodies), heteroconjugate antibodies (e.g., bispecific antibodies) and recombinant single chain Fv fragments (scFv), disulfide stabilized (dsFv) Fv fragments, or pFv fragments. The term “antibody” also includes antigen binding forms of antibodies (e.g., Fab′, F(ab′)2, Fab, Fv and rIgG. See also, Pierce Catalog and Handbook, 1994-1995 (Pierce Chemical Co., Rockford, Ill.). See also, e.g., Kuby, J., Immunology, 3rd Ed., W.H. Freeman & Co., New York (1997). An antibody immunologically reactive with a particular antigen can be generated by recombinant methods such as selection of libraries of recombinant antibodies in phage or similar vectors, see, e.g., Huse, et al., Science 246:1275-1281 (1989); Ward, et al., Nature 341:544-546 (1989); and Vaughan, et al., Nature Biotech. 14:309-314 (1996), or by immunizing an animal with the antigen or with DNA encoding the antigen. Typically, an immunoglobulin has a heavy and light chain. Each heavy and light chain contains a constant region and a variable region, (the regions are also known as “domains”). Light and heavy chain variable regions contain a “framework” region interrupted by three hypervariable regions, also called “complementarity-determining regions” or “CDRs”. The extent of the framework region and CDRs have been defined (see, Kabat, E., et al., SEQUENCES OF PROTEINS OF IMMUNOLOGICAL INTEREST, U.S. Department of Health and Human Services, (1987), which is hereby incorporated by reference). The sequences of the framework regions of different light or heavy chains are relatively conserved within a species. The framework region of an antibody, that is the combined framework regions of the constituent light and heavy chains, serves to position and align the CDRs in three dimensional space. The CDRs are primarily responsible for binding to an epitope of an antigen. The CDRs of each chain are typically referred to as CDR1, CDR2, and CDR3, numbered sequentially starting from the N-terminus, and are also typically identified by the chain in which the particular CDR is located. Thus, a VH CDR3 is located in the variable domain of the heavy chain of the antibody in which it is found, whereas a VL CDR1 is the CDR1 from the variable domain of the light chain of the antibody in which it is found. References to “VH” or a “VH” refer to the variable region of an immunoglobulin heavy chain, including an Fv, scFv, dsFv or Fab. References to “VL” or a “VL” refer to the variable region of an immunoglobulin light chain, including of an Fv, scFv, dsFv or Fab The phrase “single chain Fv” or “scFv” refers to an antibody in which the variable domains of the heavy chain and of the light chain of a traditional two chain antibody have been joined to form one chain. Typically, a linker peptide is inserted between the two chains to allow for proper folding and creation of an active binding site. The term “linker peptide” includes reference to a peptide within an antibody binding fragment (e.g., Fv fragment) which serves to indirectly bond the variable domain of the heavy chain to the variable domain of the light chain. A “targeting moiety” is the portion of an immunoconjugate intended to target the immunoconjugate to cells of interest. Typically, the targeting moiety is an antibody, a scFv, a dsFv, an Fab, or an F(ab′)2. A “toxic moiety” is the portion of a immunotoxin which renders the immunotoxin cytotoxic to cells of interest. A “therapeutic moiety” is the portion of an immunoconjugate intended to act as a therapeutic agent. The term “therapeutic agent” includes any number of compounds currently known or later developed to act as anti-neoplastics, anti-inflammatories, cytokines, anti-infectives, enzyme activators or inhibitors, allosteric modifiers, antibiotics or other agents administered to induce a desired therapeutic effect in a patient. It further includes nucleic acids, including antisense molecules. As used herein, it further encompasses prophylatic and therapeutic vaccines, such as proteins which are intended to cause a heightened immune response to an infectious disease or a cancer, as well as nucleic acids encoding such proteins. A “detectable label” means, with respect to an immunoconjugate, a portion of the immunoconjugate which has a property rendering its presence detectable. For example, the immunoconjugate may be labeled with a radioactive isotope which permits cells in which the immunoconjugate is present to be detected in immunohistochemical assays. The term “effector moiety” means the portion of an immunoconjugate intended to have an effect on a cell to which the moiety is delivered by the targeting moiety or to identify the presence of the immunoconjugate. Thus, the effector moiety can be, for example, a therapeutic moiety or a detectable label, such as a radiolabel or a fluorescent label. The terms “effective amount” or “amount effective to” or “therapeutically effective amount” includes reference to a dosage of a therapeutic agent sufficient to produce a desired result, such as inhibiting cell protein synthesis by at least 50%, or killing the cell. The term “contacting” includes reference to placement in direct physical association. An “expression plasmid” comprises a nucleotide sequence encoding a molecule of interest, which is operably linked to a promoter. As used herein, the term “anti-pIgR” in reference to an antibody, includes reference to an antibody which is generated against pIgR. In preferred embodiments, the pIgR is a primate pIgR such as human pIgR. In a preferred embodiment, the antibody is generated against human pIgR synthesized by a non-primate mammal after introduction into the animal of cDNA which encodes human pIgR. As used herein, the term “polypeptide” includes proteins, fusion proteins, oligopeptides and polypeptide derivatives, with the exception that peptidomimetics are considered to be small molecules herein. Although they are polypeptides, antibodies and their derivatives are described separately. A “protein” is a molecule having a sequence of amino acids that are linked to each other in a linear molecule by peptide bonds. The term protein refers to a polypeptide that is isolated from a natural source, or produced from an isolated cDNA using recombinant DNA technology; and has a sequence of amino acids having a length of at least about 200 amino acids. A “fusion protein” is a type of recombinant protein that has an amino acid sequence that results from the linkage of the amino acid sequences of two or more normally separate polypeptides. In the context of the present invention, the term usually refers to a ligand, such as an antibody, linke to a biologically active molecule, such as a chemotherapeutic agent or an anti-infective. A “protein fragment” is a proteolytic fragment of a larger polypeptide, which may be a protein or a fusion protein. A proteolytic fragment may be prepared by in vivo or in vitro proteolytic cleavage of a larger polypeptide, and is generally too large to be prepared by chemical synthesis. Proteolytic fragments have amino acid sequences having a length from about 200 to about 1,000 amino acids. An “oligopeptide” is a polypeptide having a short amino acid sequence (i.e., 2 to about 200 amino acids). An oligopeptide is generally prepared by chemical synthesis. Although oligopeptides and protein fragments may be otherwise prepared, it is possible to use recombinant DNA technology and/or in vitro biochemical manipulations. For example, a nucleic acid encoding an amino acid sequence may be prepared and used as a template for in vitro transcription/translation reactions. A “polypeptide derivative” includes without limitation mutant polypeptides, chemically modified polypeptides, and peptidomimetics. The polypeptides or derivatives may generally be prepared by solid phase synthetic methods as taught in, e.g., Merrifield (1964), J. Am. Chem. Soc., 85: 2149; Stewart and Young (1984), Solid Phase polypeptide Synthesis, Pierce Chemical Company, Rockford, Ill.; Bodansky and Bodanszky (1984), The Practice of polypeptide Synthesis, Springer-Verlag, New York; Atherton and Sheppard (1989), Solid Phase polypeptide Synthesis: A Practical Approach, IRL Press, New York, or by recombinant techniquest using polynucleotide sequences encoding the polypeptides. For example, fusion proteins are typically prepared using recombinant DNA technology. A “derivative” of a polypeptide is a compound that is not, by definition, a polypeptide, i.e., it contains at least one chemical linkage that is not a peptide bond. Thus, polypeptide derivatives include without limitation proteins that naturally undergo post-translational modifications such as, e.g., glycosylation. Preferred polypeptide derivatives retain a desirable attribute, which may be biological activity; more preferably, a polypeptide derivative is enhanced with regard to one or more desirable attributes, or has one or more desirable attributes not found in the parent polypeptide. A polypeptide having an amino acid sequence identical to that found in a protein prepared from a natural source is a “wildtype” polypeptide. “Mutant polypeptides” can be prepared by chemical synthesis, including without limitation combinatorial synthesis. Mutant polypeptides larger than oligopeptides can be prepared using recombinant DNA technology by altering the nucleotide sequence of a nucleic acid encoding a polypeptide. Although some alterations in the nucleotide sequence will not alter the amino acid sequence of the polypeptide encoded thereby (“silent” mutations), many will result in a polypeptide having an altered amino acid sequence that is altered relative to the parent sequence. Such altered amino acid sequences may comprise substitutions, deletions and additions of amino acids, with the proviso that such amino acids are naturally occurring amino acids. Polypeptides having deletions or insertions of naturally occurring amino acids may be synthetic oligopeptides that result from the chemical synthesis of amino acid sequences that are based on the amino acid sequence of a parent polypeptide but which have one or more amino acids inserted or deleted relative to the sequence of the parent polypeptide. Insertions and deletions of amino acid residues in polypeptides having longer amino acid sequences may be prepared by directed mutagenesis. The term “polypeptide” includes those having one or more chemical modification relative to another polypeptide, i.e., chemically modified polypeptides. The polypeptide from which a chemically modified polypeptide is derived may be a wildtype protein, a mutant protein or a mutant polypeptide, or polypeptide fragments thereof; an antibody or other polypeptide ligand according to the invention including without limitation single-chain antibodies, bacterial proteins and polypeptide derivatives thereof; or polypeptide ligands prepared according to the disclosure. Preferably, the chemical modification(s) confer(s) or improve(s) desirable attributes of the polypeptide but does not substantially alter or compromise the biological activity thereof. Desirable attributes include but are limited to increased shelf-life; enhanced serum or other in vivo stability; resistance to proteases; and the like. Such modifications include by way of non-limiting example N-terminal acetylation, glycosylation, and biotinylation. Substitution of unnatural amino acids for natural amino acids in a subsequence of a polypeptide can confer or enhance desirable attributes including biological activity. Such a substitution can, for example, confer resistance to proteolysis by exopeptidases acting on the N-terminus. The synthesis of polypeptides with unnatural amino acids is routine and known in the art. Different host cells will contain different post-translational modification mechanisms that may provide particular types of post-translational modification of a fusion protein if the amino acid sequences required for such modifications is present in the fusion protein. A large number (˜100) of post-translational modifications have been described. One skilled in the art will be able to choose appropriate host cells, and design chimeric genes that encode protein members comprising the amino acid sequence needed for a particular type of modification. Glycosylation is one type of post-translational chemical modification that occurs in many eukaryotic systems, and may influence the activity, stability, pharmacogenetics, immunogenicity and/or antigenicity of proteins. Another type of post-translation modification is the phosphorylation of a free hydroxyl group of the side chain of one or more Ser, Thr or Tyr residues. Protein kinases catalyze such reactions. Phosphorylation is often reversible due to the action of a protein phosphatase, an enzyme that catalyzes the dephosphorylation of amino acid residues. Differences in the chemical structure of amino terminal residues result from different host cells, each of which may have a different chemical version of the methionine residue encoded by a start codon, and these will result in amino termini with different chemical modifications. For example, many or most bacterial proteins are synthesized with an amino terminal amino acid that is a modified form of methionine, i.e, N-formyl-methionine (fMet). In eukaryotes, acetylation of the initiator methionine residue, or the penultimate residue if the initiator methionine has been removed, typically occurs co- or post-translationally. The acetylation reactions are catalyzed by N-terminal acetyltransferases (NATs, a.k.a. N-alpha-acetyltransferases), whereas removal of the initiator methionine residue is catalyzed by methionine aminopeptidases (for reviews, see Bradshaw et al., Trends Biochem. Sci. 23:263-267, 1998; and Driessen et al., CRC Crit. Rev. Biochem. 18:281-325, 1985). Amino terminally acetylated proteins are said to be “N-acetylated,” “N alpha acetylated” or simply “acetylated.” A polypeptide mimetic (“peptidomimetic”) is a molecule that mimics the biological activity of a polypeptide but is no longer peptidic in chemical nature. By strict definition, a peptidomimetic is a molecule that contains no peptide bonds (that is, amide bonds between amino acids). However, the term peptidomimetic is sometimes used to describe molecules that are no longer completely peptidic in nature, such as pseudo-peptides, semi-peptides and peptoids. Whether completely or partially non-peptide, peptidomimetics according to this invention provide a spatial arrangement of reactive chemical moieties that closely resembles the three-dimensional arrangement of active groups in the polypeptide on which the peptidomimetic is based. As a result of this similar active-site geometry, the peptidomimetic has effects on biological systems that are similar to the biological activity of the polypeptide. There are several potential advantages for using a mimetic of a given polypeptide rather than the polypeptide itself. For example, polypeptides may exhibit two undesirable attributes, i.e., poor bioavailability and short duration of action. Peptidomimetics are often small enough to be both orally active and to have a long duration of action. There are also problems associated with stability, storage and immunoreactivity for polypeptides that are not experienced with peptidomimetics. Candidate, lead and other polypeptides having a desired biological activity can be used in the development of peptidomimetics with similar biological activities. Techniques of developing peptidomimetics from polypeptides are known. Peptide bonds can be replaced by non-peptide bonds that allow the peptidomimetic to adopt a similar structure, and therefore biological activity, to the original polypeptide. Further modifications can also be made by replacing chemical groups of the amino acids with other chemical groups of similar structure. The development of peptidomimetics can be aided by determining the tertiary structure of the original polypeptide, either free or bound to a ligand, by NMR spectroscopy, crystallography and/or computer-aided molecular modeling. These techniques aid in the development of novel compositions of higher potency and/or greater bioavailability and/or greater stability than the original polypeptide (Dean (1994), BioEssays, 16: 683-687; Cohen and Shatzmiller (1993), J. Mol. Graph., 11: 166-173; Wiley and Rich (1993), Med. Res. Rev., 13: 327-384; Moore (1994), Trends Pharmacol. Sci., 15: 124-129; Hruby (1993), Biopolymers, 33: 1073-1082; Bugg et al. (1993), Sci. Am., 269: 92-98, all incorporated herein by reference]. As used herein, “recombinant” includes reference to a protein produced using cells that do not have, in their native state, an endogenous copy of the DNA able to express the protein. The cells produce the recombinant protein because they have been genetically altered by the introduction of the appropriate isolated nucleic acid sequence. The term also includes reference to a cell, or nucleic acid, or vector, that has been modified by the introduction of a heterologous nucleic acid or the alteration of a native nucleic acid to a form not native to that cell, or that the cell is derived from a cell so modified. Thus, for example, recombinant cells express genes that are not found within the native (non-recombinant) form of the cell, express mutants of genes that are found within the native form, or express native genes that are otherwise abnormally expressed, underexpressed or not expressed at all. As used herein, “nucleic acid” or “nucleic acid sequence” includes reference to a deoxyribonucleotide or ribonucleotide polymer in either single- or double-stranded form, and unless otherwise limited, encompasses known analogues of natural nucleotides that hybridize to nucleic acids in a manner similar to naturally occurring nucleotides. Unless otherwise indicated, a particular nucleic acid sequence includes the complementary sequence thereof as well as conservative variants, i.e., nucleic acids present in wobble positions of codons and variants that, when translated into a protein, result in a conservative substitution of an amino acid. As used herein, “encoding” with respect to a specified nucleic acid, includes reference to nucleic acids which comprise the information for translation into the specified protein. The information is specified by the use of codons. Typically, the amino acid sequence is encoded by the nucleic acid using the “universal” genetic code. However, variants of the universal code, such as is present in some plant, animal, and fungal mitochondria, the bacterium Mycoplasma capricolum (Proc. Nat'l Acad. Sci. USA 82:2306-2309 (1985), or the ciliate Macronucleus, may be used when the nucleic acid is expressed in using the translational machinery of these organisms. The phrase “fusing in frame” refers to joining two or more nucleic acid sequences which encode polypeptides so that the joined nucleic acid sequence translates into a single chain protein which comprises the original polypeptide chains. As used herein, “expressed” includes reference to translation of a nucleic acid into a protein. Proteins may be expressed and remain intracellular, become a component of the cell surface membrane or be secreted into the extracellular matrix or medium. By “host cell” is meant a cell which can support the replication or expression of the expression vector. Host cells may be prokaryotic cells such as E. coli, or eukaryotic cells such as yeast, insect, amphibian, or mammalian cells. By “bind(s) specifically” or “specifically bind(s)” or “attached” or “attaching” is meant the preferential association of a ligand, in whole or part, with a cell or tissue bearing a particular target molecule or marker and not to cells or tissues lacking that target molecule. It is, of course, recognized that a certain degree of non-specific interaction may occur between a molecule and a non-target cell or tissue. Nevertheless, specific binding, may be distinguished as mediated through specific recognition of the target molecule. Typically specific binding results in a much stronger association between the delivered molecule and cells bearing the target molecule than between the bound molecule and cells lacking the target molecule. Specific binding typically results in greater than 2 fold, preferably greater than 5 fold, more preferably greater than 10 fold and most preferably greater than 100 fold increase in amount of bound ligand (per unit time) to a cell or tissue bearing the target molecule as compared to a cell or tissue lacking the target molecule or marker. By “biologically active component” is meant a compound which, in vivo, directly causes or inhibits an increase or decrease in cellular transcription, translation, receptor binding, active or passive transport, cell signaling, signal transduction, cell division, cell differentiation, cell death, cell adhesion, cell movement, cell morphology, metabolism, enzyme activity, apoptosis, protein degradation, protein movement (e.g., secretion), protein stability, or phosphorylation. Biologically active components also comprise diagnostic compositions which allow the foregoing events to be assessed. A “biologically active component—ligand conjugate” refers to a chimeric molecule comprised of a biologically active component coupled to a targeting moiety, such as an antibody or a scFv, which confers on the conjugate the ability to bind selectively to a target. In the case of a scFv for example, the target is typically a cell bearing an antigen to which the scFv specifically binds. By “domain” or “substructure” of a protein is meant a portion of a protein, which portion has a defined functionality. Such domains or substructures include catalytic domains of enzymes, regulatory domains of enzymes, cytoplasmic domains of transmembrane proteins, signaling domains, such as src homology domain 2 and domain 3 (known in the art as SH2 and SH3), and the pleckstrin homology domain. Fragments of antibodies which retain antigen recognition, such as Fab, scFv, dsFv, and the like, also can be considered domains or substructures of proteins for purposes of this invention. By “not substantially bind” is meant that no more than 15% of a ligand which specifically binds to a target molecule is bound to a particular non-target molecule. More preferably, no more than 10% is bound to the non-target molecule, even more preferably less than 5%, and most preferably less than 1%. The term “physiological conditions” is used herein in two meanings. With reference to culturing cells or the like, it means an extracellular milieu having conditions (e.g., temperature, pH, and osmolarity) which allows for the sustenance or growth of a cell of interest. With reference to the species of secretory component (SC) which is most abundant under such conditions, “physiological conditions” refers to the conditions normally present in the organ of interest or tissue of interest, such as the lumen of the small or large intestine. By “humanized antibody” is meant an antibody which comprises a non-human amino acid sequence but whose constant region has been altered to reduce immunogenicity in humans. By “apical surface” is meant that surface of a cell to which intact pIgR is transcytosed to after endocytosis from the basolateral surface. Generally, the apical surface of the cell adjoins a lumen and once pIgR is secreted from the cell surface, the pIgR is cleaved to release the secretory component, leaving a region proximal to the cell (the stalk) attached. By “basolateral surface” is meant that surface of a cell from which intact pIgR is delivered to after synthesis in the endoplasmic reticulum and passage through the Golgi complex. By “transcytosed” or “transcytosis” is meant conveyance from one plasma membrane of the cell to another via an intracellular route. Typically, transcytosis occurs from the basolateral to apical or apical to basolateral plasma membrane of the cell. “Retrograde” motion is motion from the apical to the basolateral surfaces of the cell. By “cell membrane proximal” is meant next to or nearer the cell membrane. By “extracellular” is meant the region extending outward from the lipid bilayer encompassing a cell. The term “residue” or “amino acid residue” or “amino acid” includes reference to an amino acid that is incorporated into a protein, polypeptide, or peptide (collectively “peptide”). The amino acid can be a naturally occurring amino acid and, unless otherwise limited, can encompass known analogs of natural amino acids that can function in a similar manner as naturally occurring amino acids. The amino acids and analogs referred to herein are described by shorthand designations as follows in Table 1: TABLE 1 Amino Acid Nomenclature Name 3-letter 1-letter Alanine Ala A Arginine Arg R Asparagine Asn N Aspartic Acid Asp D Cysteine Cys C Glutamic Acid Glu E Glutamine Gln Q Glycine Gly G Histidine His H Isoleucine Ile I Leucine Leu L Lysine Lys K Methionine Met M Phenylalanine Phe F Proline Pro P Serine Ser S Threonine Thr T Tryptophan Trp W Tyrosine Tyr Y Valine Val V A “conservative substitution”, when describing a protein refers to a change in the amino acid composition of the protein that does not substantially alter the protein's activity. Thus, “conservatively modified variations” of a particular amino acid sequence refers to amino acid substitutions of those amino acids that are not critical for protein activity or substitution of amino acids with other amino acids having similar properties (e.g., acidic, basic, positively or negatively charged, polar or non-polar, etc.) such that the substitutions of even critical amino acids do not substantially alter activity. Conservative substitution tables providing functionally similar amino acids are well known in the art. The following six groups in Table 2 each contain amino acids that are conservative substitutions for one another: TABLE 2 1) Alanine (A), Serine (S), Threonine (T); 2) Aspartic acid (D), Glutamic acid (E); 3) Asparagine (N), Glutamine (Q); 4) Arginine (R), Lysine (K); 5) Isoleucine (I), Leucine (L), Methionine (M), Valine (V); and 6) Phenylalanine (F), Tyrosine (Y), Tryptophan (W). See also, Creighton, PROTEINS, W.H. Freeman and Company, New York (1984). The terms “substantially similar” in the context of a peptide indicates that a peptide comprises a sequence with at least 90%, preferably at least 95% sequence identity to the reference sequence over a comparison window of 10-20 amino acids. Percentage of sequence identity is determined by comparing two optimally aligned sequences over a comparison window, wherein the portion of the polynucleotide sequence in the comparison window may comprise additions or deletions (i.e., gaps) as compared to the reference sequence (which does not comprise additions or deletions) for optimal alignment of the two sequences. The percentage is calculated by determining the number of positions at which the identical nucleic acid base or amino acid residue occurs in both sequences to yield the number of matched positions, dividing the number of matched positions by the total number of positions in the window of comparison and multiplying the result by 100 to yield the percentage of sequence identity. The Polymeric Immunoglobulin Receptor The nucleic acid and amino acid sequence of the polymeric immunoglobulin receptor has been identified in a variety of taxonomically diverse species. See, Piskurich et al., Journal of Immunology 154:1735-1747 (1995). The alignment and sequences of a number of mammalian pIgRs are shown in Mostov, K. E. and Kaetzel, C. “Immunoglobulin transport and the polymeric immunoglobulin receptor,” In: Mucosal Immunology, P. L. Ogra, et al., (eds.), Academic Press, Inc., New York, pp. 181-211 (2nd ed., 1999) (hereafter, “Mostov and Kaetzel”). The amino acid sequences for the pIgR of for a number of mammalian species have been aligned and set forth in the art. Identification of pIgR from other species can be accomplished by any number of methods well known to those of skill in the art. For example, using published pIgR sequences, a nucleic acid probe to pIgR can be constructed. The probe typically should be derived from a conserved region of pIgR. Hybridization of the probe to a genomic or cDNA library can be used to identify pIgR in an unknown species. It will be understood by the skilled artisan that the nucleic acid sequence of the pIgR probe should generally be that of the species most closely related to the probed species. An extensive guide to the hybridization of nucleic acids is found in Tijssen (1993) Laboratory Techniques in Biochemistry and Molecular Biology—Hybridization with Nucleic Acid Probes Part I, Chapter 2 “Overview of principles of hybridization and the strategy of nucleic acid probe assays”, Elsevier, New York. In an alternative approach, pIgR or peptide fragments thereof (e.g., secretory component) can be used to create antibodies to screen expression libraries. See, e.g., Ferkol et al., J. Clin. Invest. 95:493-502 (1995). These and other methods well known to the skilled artisan may be found, for example, in Berger and Kimmel, Guide to Molecular Cloning Techniques, Methods in Enzymology volume 152 Academic Press, Inc., San Diego, Calif. (Berger); Sambrook et al. (1989) Molecular Cloning—A Laboratory Manual (2nd ed.) Vol. 1-3; and Current Protocols in Molecular Biology, F. M. Ausubel et al., eds., Current Protocols, a joint venture between Greene Publishing Associates, Inc. and John Wiley & Sons, Inc., (1994 Supplement) (Ausubel). Confirmation of the identity of a nucleic acid or protein as encoding pIgR may be had by such approaches as constructing antibodies to the putative pIgR protein and confirming the ability of these antibodies to bind to a protein having the characteristics of pIgR (e.g., being present on the surface of epithelial cells, binding of dimeric IgA or pentameric IgM, etc.). The nucleic acid and amino acid sequence of the polymeric immunoglobulin receptor has been identified in a variety of taxonomically diverse species. See, Piskurich et al., Journal of Immunology 154:1735-1747 (1995). The sequence of human pIgR is set forth, inter alia, in Eiffert et al., Hoppe Seyler's Z. Physiol. Chem. Bd. 365, S.1489-1495 (1984), and in Hughes et al., FEBS Letters 410:443-446 (1997), and further set forth in SWISS-PROT, a curated protein sequence database maintained by the European Molecular Biology Laboratory Data Library, under accession number P01833 (the sequence is publicly available on the World Wide Web at, e.g., expasy.ch/cgi-bin/sprot-search-ac?P01833). The numbering in SWISS-PROT (see, e.g., SEQ ID NO:1) includes an 18-residue leader sequence; thus, references to particular residues in the SWISS-PROT database are 18 numbers higher than the numbers accorded the same residues by references which do not include the leader sequence (such as Hughes et al. and the Mostov and Kaetzel reference), even though they refer to the same protein. References herein to one or more numbered residues of human pIgR are to the residues as numbered in the SWISS-PROT database. The SWISS-PROT database also reports that an alanine to valine variant has been found at position 580 of the sequence. Ligands that bind to B regions containing this or other similar variants are encompassed within the present invention. Such variants include variants of the sequence set forth in SWISS-PROT so long as they do not destroy the function of the variant pIgR molecule as a receptor for polymeric immunoglobulin and do not destroy the ability of the variant pIgR molecule to internalize and transcytose a ligand bound to it. Assays for determining internalization and transcytosis of a bound ligand are set forth in the Examples. Methods of alignment of sequences for comparison are well-known in the art. Optimal alignment of sequences for comparison may be conducted by the local homology algorithm of Smith and Waterman (1981) Adv. Appl. Math. 2: 482; by the homology alignment algorithm of Needleman and Wunsch (1970) J. Mol. Biol. 48: 443; by the search for similarity method of Pearson and Lipman (1988) Proc. Natl. Acad. Sci. USA 85: 2444; by computerized implementations of these algorithms (including, but not limited to CLUSTAL in the PC/Gene program by Intelligenetics, Mountain View, Calif., GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group (GCG), 575 Science Dr., Madison, Wis., USA); the CLUSTAL program is well described by Higgins and Sharp (1988) Gene, 73: 237-244 and Higgins and Sharp (1989) CABIOS 5: 151-153; Corpet, et al. (1988) Nucleic Acids Research 16, 10881-90; Huang, et al. (1992) Computer Applications in the Biosciences 8, 155-65, and Pearson, et al. (1994) Methods in Molecular Biology 24, 307-31. Alignment is also often performed by inspection and manual alignment. The alignment and sequences of a number of mammalian pIgRs are shown in Mostov, K. E. and Kaetzel, C. “Immunoglobulin transport and the polymeric immunoglobulin receptor,” In: Mucosal Immunology, P. L. Ogra, et al., (eds.), Academic Press, Inc., New York, pp. 181-211 (2nd ed., 1999). Identification of pIgR The nucleic acid and amino acid sequence of the polymeric immunoglobulin receptor has been identified in a variety of taxonomically diverse species. See, Piskurich et al., Journal of Immunology 154:1735-1747 (1995). The alignment and sequences of a number of mammalian pIgRs are shown in Mostov, K. E. and Kaetzel, C. “Immunoglobulin transport and the polymeric immunoglobulin receptor,” In: Mucosal Immunology, P. L. Ogra, et al., (eds.), Academic Press, Inc., New York, pp. 181-211 (2nd ed., 1999) (hereafter, “Mostov and Kaetzel”). The amino acid sequences for the pIgR of six mammalian species are aligned and set forth in FIG. 1. Identification of pIgR from other species can be accomplished by any number of methods well known to those of skill in the art. For example, using published pIgR sequences, a nucleic acid probe to pIgR can be constructed. The probe typically should be derived from a conserved region of pIgR. Hybridization of the probe to a genomic or cDNA library can be used to identify pIgR in an unknown species. It will be understood by the skilled artisan that the nucleic acid sequence of the pIgR probe should generally be that of the species most closely related to the probed species. An extensive guide to the hybridization of nucleic acids is found in Tijssen (1993) Laboratory Techniques in Biochemistry and Molecular Biology—Hybridization with Nucleic Acid Probes Part I, Chapter 2 “Overview of principles of hybridization and the strategy of nucleic acid probe assays”, Elsevier, New York. In an alternative approach, pIgR or peptide fragments thereof (e.g., secretory component) can be used to create antibodies to screen expression libraries. See, e.g., Ferkol et al., J. Clin. Invest. 95:493-502 (1995). These and other methods well known to the skilled artisan may be found, for example, in Berger and Kimmel, Guide to Molecular Cloning Techniques, Methods in Enzymology volume 152 Academic Press, Inc., San Diego, Calif. (Berger); Sambrook et al. (1989) Molecular Cloning—A Laboratory Manual (2nd ed.) Vol. 1-3; and Current Protocols in Molecular Biology, F. M. Ausubel et al., eds., Current Protocols, a joint venture between Greene Publishing Associates, Inc. and John Wiley & Sons, Inc., (1994 Supplement) (Ausubel). Confirmation of the identity of a nucleic acid or protein as encoding pIgR may be had by such approaches as constructing antibodies to the putative pIgR protein and confirming the ability of these antibodies to bind to a protein having the characteristics of pIgR (e.g., being present on the surface of epithelial cells, binding of dimeric IgA or pentameric IgM, etc.). Identification of the Initial SC Cleavage Site A putative heptapeptide consensus sequence which identifies the cleavage site of pIgR and thereby defines the amino terminus of the stalk has previously been identified. The sequence Phe-Ala-X-Glu, where X is a polar or charged amino acid, was identified as immediately preceding this putative cleavage site. Piskurich et al., Journal of Immunology 154:1735-1747 (1995). It appears now that there is some conflicting evidence regarding the cleavage site and that there may be different cleavage sites depending on the particular species and the particular organ in which the pIgR is expressed. Thus, the C-terminus of the B region may vary according to the particular species of organism under consideration. One of skill can, however, readily determine whether a particular ligand binds to the B region of any particular species of organism. Where the sites of cleavage differ among the organs of a particular organism, the relevant B region for purposes of this invention is preferably that of the animal's intestinal tract. The cleavage liberates the secretory component and defines its initial carboxy terminus. The carboxy terminus of secretory component is then altered by secondary cleavage events (e.g., exopeptidase or endopeptidase activity) to yield secondary carboxy termini. Mostov and Kaetzel, supra, reviews and summarizes much of the available information regarding SC cleavage. They note that Hughes et al., FEBS Letters 410:443-446 (1997), isolated human colostrum SC from a single individual and showed that the C terminal residue was Arg585. In contrast, earlier work published in German (Eiffert, et al, Hoppe Seyler's Z. Physiol. Chem. Bd. 365, S.1489-1495 (1984), found a “ragged” (i.e. variable C-terminus of SC from human colostrum (pooled from several individuals). The C-termini that they reported were Ala550, Gly551, Ser552, Ala558, and Lys559. (The numbering of the residues in Eiffert et al. is considered by those of skill to be off by one. The numbering of the residues set forth in the text have been corrected to their accepted numbering as set forth in the SWISS-PROT database (see SEQ ID NO:2), and in other sources. For ease of reference, the numbering used by those of skill is used in the text herein. In Eiffert et al., the residues mentioned above were designated Ala449, Gly550, Ser551, Ala557, and Lys558, respectively.) The predominant species ended in Ser552. It appears that in human mammary gland (at least during the first few days post partum when colostrum is being produced) an initial cleavage occurs at Arg585 or even closer to the C-terminus. Subsequently, secondary cleavages occur to chew the C-terminus back to between Ala550 and Lys559. It thus appears that Eiffert et al were studying SC that had been subject to secondary cleavages, whereas Hughes et al. had studied SC that either had not been subject to secondary cleavage, or at least to less secondary cleavage than Eiffert et al.'s samples. Some of the putative cleavage sites are denoted in FIG. 1 (which is taken from Mostov and Kaetzel) by vertical arrows. Thus, in the mammary gland, the N terminus of the B region can start, for example, from Lys 559, from the most abundant C-terminus, Ser551, found by Eiffert et al., or from Ala550. In tissues other than mammary gland, there may be additional secondary cleavages, so the B region may extend even further towards the N-terminal region of the protein. This is more likely to occur in the intestinal tract, where the level of proteases is much higher than that present in colostrum. Ahnen et al (J. Clin. Invest 77:1841-1848 (1986)) reported that SC isolated from the lumen of rat intestine had a molecular weight 10,000 to 20,000 Daltons smaller than SC from rat bile. They hypothesized that the SC in the rat intestinal lumen had undergone more secondary cleavage, accounting for the decrease in MW. They did not report the C-terminal residues of any of these forms of SC, so the exact sites of cleavage were not shown. Based on the size of SC isolated from the intestinal lumen by Ahnen et al. though, it appears that the N terminal end of the B region (and, thus, the C terminal end of fully processed free SC) commences at or about the residue marked “Bridge to IgA” in FIG. 1. The exact N-terminal boundary of the B region is likely to be variable. This is to be expected, as secondary cleavages (especially exoproteases) may leave a ragged end. This merely means that a ligand targeted to the terminal portions of the B region may or may not bind in small amounts to a free SC which still has the target epitope present. In more preferred embodiments, the ligands are targeted to epitopes which are promptly degraded on all or most SC after cleavage and are therefore always within a B region. Any particular ligand can be tested for whether it binds to the B region, to the stalk, or to the major species of SC present in an organ of interest or on a tissue of interest by assays known in the art, including the exemplary assays set forth in the Examples. One Example demonstrates the use of SC from the lumen of the intestines of sacrificed Cynomologous monkeys. SC from the gastrointestinal tract of monkeys and other mammals can further also be obtained by, for example, taking fluid samples from the colon by endoscopy. Samples of human intestinal SC can be obtained directly by such procedures as endoscopy, sigmoidoscopy, or colonoscopy, or by surgical procedures. Similarly, samples from the lung or uterus can be obtained by endoscopy or surgical procedures. Samples from organs such as the vagina and from tissues such as the nasal passages and lacrimal glands can be obtained by swabs and other routine medical procedures. Once obtained, sample can be treated with a “cocktail” of protease inhibitors to prevent further degradation of the pIgR and of any cleaved SC, and to permit determination of the major form of SC present in the sample. Sequences of pIgR from different species can be aligned, as in FIG. 1. It should be noted that FIG. 1 employs various gaps and insertions to align the sequences of the different species and the numbering used is a “unified” numbering that does not correspond to any one species. The sequence of human pIgR is set forth, inter alia, in Eiffert et al., supra, and in Hughes et al., supra, and further set forth in SWISS-PROT, a curated protein sequence database maintained by the European Molecular Biology Laboratory Data Library, under accession number P01833 (the sequence is set forth herein as FIG. 2 and is publicly available on the World Wide World at, e.g., expasy.ch/cgi-bin/sprot-search-ac?P01833). The numbering in SWISS-PROT includes the 18-residue leader sequence shown in FIG. 1; thus, references to particular residues in the SWISS-PROT database are 18 numbers higher than the numbers accorded the same residues by references which do not include the leader sequence (such as Hughes et al.), even though they refer to the same protein. References below to one or more numbered residues of human pIgR are to the residues as numbered in the SWISS-PROT database. Methods of alignment of sequences for comparison are well-known in the art. Optimal alignment of sequences for comparison may be conducted by the local homology algorithm of Smith and Waterman (1981) Adv. Appl. Math. 2: 482; by the homology alignment algorithm of Needleman and Wunsch (1970) J. Mol. Biol. 48: 443; by the search for similarity method of Pearson and Lipman (1988) Proc. Natl. Acad. Sci. USA 85: 2444; by computerized implementations of these algorithms (including, but not limited to CLUSTAL in the PC/Gene program by Intelligenetics, Mountain View, Calif., GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group (GCG), 575 Science Dr., Madison, Wis., USA); the CLUSTAL program is well described by Higgins and Sharp (1988) Gene, 73: 237-244 and Higgins and Sharp (1989) CABIOS 5: 151-153; Corpet, et al. (1988) Nucleic Acids Research 16, 10881-90; Huang, et al. (1992) Computer Applications in the Biosciences 8, 155-65, and Pearson, et al. (1994) Methods in Molecular Biology 24, 307-31. Alignment is also often performed by inspection and manual alignment. In another approach, secretory component can be isolated from fluids in the apical lumen (e.g., vaginal mucus, milk, and bile) or on surfaces proximal to the secreting cells (e.g., nasal mucus, tears) and sequenced by amino acid sequencing methods well known to those of skill such as Edman degradation, or mass spectrometry. Eiffert et al., Hoppe-Seyler's Z. Physiol. Chem. 365:1489-1495 (1984). Among the various secondary carboxyl ends defined by secondary cleavage events, the carboxy terminal amino acid adjacent to the cleavage site can be identified. Identification of the Stalk The stalk can be identified by a variety of techniques well known to those of skill. For example, cells expressing pIgR can be subjected to proteolytic cleavage, the cleaved product washed away, the cell sonicated, the remaining portion of pIgR immobilized by antibodies generated against the cytoplasmic domain, and the protein then subjected to standard chemical degradation to determine the sequence of the amino acids on the N-terminal side of the transmembrane domain, thereby defining the stalk. Alternatively, the putative stalk region of the species of interest can be immobilized on a support. A library of scFv, such as human scFv, displayed as fusion proteins on filamentous phage, is then screened for phage displaying scFv that bind to the immobilized stalk. After several rounds of enrichment, phage which bind to the stalk can be selected and its binding to the stalk confirmed by ELISA. DNA from phage of interest can then be subcloned into expression vectors to facilitate larger scale production. In preferred embodiments, the stalk is identified by use of antibodies specific for the first 15-30 amino acids of pIgR extracellular to the transmembrane domain of the species of interest. An exemplary protocol for generating antibodies identifying the stalk region of pIgR is set forth in Example 1. Peptides that correspond to the pIgR stalks of mouse, rat, human, bovine, and rabbit are set forth as SEQ ID NOS:2, 3, 4, 5, and 6 of U.S. Pat. No. 6,042,833. In particular, SEQ ID NO:4 of the '833 patent sets forth the peptide corresponding to the stalk of human pIgR as: Glu-Lys-Ala-Val-Ala-Asp-Thr-Arg-Asp-Gln-Ala-Asp-Gly-Ser-Arg-Ala-Ser-Val-Asp-Ser-Gly-Ser-Ser-Glu-Glu-Gln-Gly-Gly-Ser-Ser-Arg. In preferred embodiments, the ligands of the invention do not substantially bind to an extracellular epitope within the first 33 amino acids that are cell membrane proximal to the initial pIgR cleavage site. Cells Expressing pIgR The present invention broadly pertains to eukaryotic cells. The pIgR expressing cell of the present invention is preferably a mammalian cell and more preferably a mammalian epithelial cell that normally secretes IgA. Mammalian cells can be transfected with a nucleic acid encoding pIgR isolated, synthesized or otherwise derived from one or more desired species. Methods of transfecting and expressing genes in mammalian cells are known in the art. Transducing cells with viral vectors can involve, for example, incubating viruses with cells within the viral host range under conditions and concentrations necessary to cause infection. See, e.g., Methods in Enzymology, vol. 185, Academic Press, Inc., San Diego, Calif. (D. V. Goeddel, ed.) (1990) or M. Krieger, Gene Transfer and Expression—A Laboratory Manual, Stockton Press, New York, N.Y., (1990) and the references cited therein. The culture of cells which can be used in the present invention include cell lines and cultured cells from tissue is well known in the art. Freshney (Culture of Animal Cells, a Manual of Basic Technique, Wiley-Liss, New York (3rd ed., 1994)) and the references cited therein provides a general guide to the culture of cells. The nucleic acid sequences encoding pIgR from the desired species may be expressed in a variety of eukaryotic host cells, including yeast, and various higher eukaryotic cells such as the COS, CHO and HeLa cells lines and myeloma cell lines as well as MDCK and human colon carcinoma derived cells such as Caco2. The recombinant protein gene will be operably linked to appropriate expression control sequences for each host. For eukaryotic cells, the control sequences will include a promoter and preferably an enhancer derived, for example, from immunoglobulin genes, SV40, cytomegalovirus, etc., and a polyadenylation sequence, and may include splice donor and acceptor sequences. Binding Ligands to the pIgR B Region The specific ligand is not critical to this invention and various ligands may be used. A host of methods for construction and selection of ligands such as nucleic acids, proteins or peptides (collectively, “peptides), or antibodies, or small organic or inorganic molecules (e.g., U.S. Pat. No. 5,143,854; WO 90/15070; WO 92/10092; WO 96/11878) having the desired specific binding characteristics are well known in the art. Preferably, ligands of the present invention will, under physiological conditions, not bind to the stalk and will not substantially bind to the major species of the secretory component of pIgR present in the tissue or organ of interest (for example, the mammalian intestine) under physiological conditions (that is, that the ligand will not bind to a portion of mature SC after completion of the secondary proteolytic cleavages which occur following cleavage of the SC from intact pIgR). Typical physiological conditions vary from tissue to tissue and can also vary with certain disease conditions. For example, some intestinal tract conditions may affect the secretion of proteases and alter somewhat the timing and nature of the secondary proteolytic cleavages affecting the most abundant form of the SC present. However, the most abundant form of the SC present in a particular organ or tissue, such as the intestine, lung, vagina, nose, or lacrimal gland, during particular disease states, and in particular organisms, can be determined easily using the assays taught herein. In preferred embodiments, the ligand further binds to a portion of the SC and inhibits cleavage of the SC from the pIgR by its binding. Without wishing to be bound by theory, it is believed that binding of a ligand to epitopes close to the initial cleavage site sterically inhibit pIgR cleavage by impeding or even blocking access of protease to the cleavage site. Preferably, the ligand inhibits cleavage by at least one-quarter (25 %). In more preferred embodiments, binding of the ligand inhibits SC cleavage by 30%, 33⅓%, 40%, 50%, 60%, 66%, 70%, 75%, or even higher percentages. In some preferred embodiments, the ligand binds to an epitope present in intact pIgR prior to cleavage but which is not present in the pIgR stalk once cleavage has occurred. Thus, in this group of embodiments, the ligands typically bind to epitopes which span the cleavage site, but do not bind to epitopes present in the stalk after the pIgR is cleaved. Such ligands do not, for example, bind to a peptide consisting of the first 31 amino acids counting from the surface of cell membrane to the pIgR initial cleavage site and, in a further group of embodiments, do not bind to a peptide consisting of the first 33 amino acids counting from the surface of cell membrane to the pIgR initial cleavage site. Antibodies, including polyclonal, monoclonal, or recombinant single chain Fv antibodies, can be constructed for use as ligands in the present invention. Methods of producing polyclonal and monoclonal antibodies are known to those of skill in the art. See, e.g., Coligan (1991) Current Protocols in Immunology Wiley/Greene, NY; and Harlow and Lane (1989) Antibodies: A Laboratory Manual Cold Spring Harbor Press, NY; Stites et al. (eds.) Basic and Clinical Immunology (4th ed.) Lange Medical Publications, Los Altos, Calif., and references cited therein; Goding (1986) Monoclonal Antibodies: Principles and Practice (2d ed.) Academic Press, New York, N.Y.; and Kohler and Milstein (1975) Nature 256: 495-497; See, Huse et al. (1989) Science 246: 1275-1281; and Ward, et al. (1989) Nature 341: 544-546. Birch and Lennox, Monoclonal Antibodies: Principles and Applications, Wiley-Liss, New York, N.Y. (1995). As noted above, an exemplary protocol for generating antibodies identifying the stalk region of pIgR is set forth in Example 1. The same protocol can be employed to generate antibodies against the B region by substituting peptides selected from the B region of the animal species of interest for the peptides of the stalk region in the Example (FIG. 1 sets forth the amino acid sequences of the pIgR for a number of species). The Examples further set forth a protocol by which polyclonal goat antibodies were generated to peptides generated from a portion of the sequence of rat pIgR (the portion of rat pIgR used comprises the B region and the stalk). In general, peptides from anywhere within the B region can be used. Typically, such antibodies will be generated by using a peptide sequence selected from about the first 50 amino acid residues adjacent to the primary pIgR cleavage site, on the side distal from the surface of the pIgR-expressing cell. More preferably, the peptide chosen should be selected from about the first 40 amino acid residues and even more preferably from about the first 30 amino acid residues. The length of the particular peptide chosen should be long enough to act by itself as an antigen; shorter peptides should be coupled to a hapten to generate an immunogenic response. While any peptides of the B region can be tested for their ability to raise antibodies specific for the B region, the following are exemplary of peptides from the human sequence which can be used to generate ligands of the invention: Lys487-Arg603; Lys487-Glu607; Lys487-Val611; Lys487-Arg615; Lys487-Ala618; Cys520-Arg603; Cys520-Glu607; Cys520-Val611; Cys520-Arg615; Cys520-Ala618; Lys577-Arg603; Lys577-Glu607; Lys577-Val611; Lys577-Arg615; Lys577-Ala618; Ser574-Arg603; Ser574-Glu607; Ser574-Val611; Ser574-Arg615; Ser574-Ala618; Val560-Arg603; Val560-Glu607; Val560-Val611; Val560-Arg615; Val560-Ala618; Cys544-Arg603; Cys544-Glu607; Cys544-Val611; Cys544-Arg615; and Cys544-Ala618. Following the nomenclature of the art, the peptides are set forth listing their first and last amino acid residues, in three letter code, and their position in the sequence of the intact molecule (to avoid confusion, amino acid residues of the SC and the stalk are also referred to where appropriate by their position in the sequence of the intact pIgR molecule). As previously noted, the numbering used herein for referring to residues of human pIgR is that set forth in SWISS-PROT under accession number P01833, as shown in FIG. 2. Thus, for example, the first peptide consists of the amino acid residue Lysine at position 487 of the sequence set forth in SWISS-PROT through and including the Arginine at position 603 of the SWISS-PROT sequence. Alternatively, one can generate antibodies against full-length pIgR and screen the antibodies against peptides of the B region to select those which specifically bind to the B region. A number of techniques are known in the art for such selections. Conveniently, one can perform the selection by immobilizing the peptides of interest on a support, such as a dish or on beads on a column, and running over the surface of the dish or the beads the medium containing the antibodies. Antibodies which do not recognize the B region will not bind, and can be washed off the surfaces, leaving behind those which do bind to the B region peptides. If desired, the antibodies can then be eluted from the surface and screened against peptides of the stalk (such as those of various exemplary species set forth above in the section on identification of the stalk), or of the processed SC, or both, if desired, to ensure that the antibodies are not reactive with the stalk or with the SC. If desired, antibodies passing these screens can then be tested to determine whether they inhibit cleavage of SC, as set forth in the next section. In a variation on this technique, polyclonal antibodies were raised in goats to a glutathione-S-transferase (“GST”)-fusion peptide in which the fusion peptide comprised the rat pIgR B region and stalk. (GST was used not only to permit recombinant expression of the fusion peptide, but also ready purification of the peptide on glutathione columns). Antibodies raised in goats challenged with the fusion peptide were screened against 15-mer peptides immobilized in 96-well microtiter plates and detected by ELISAs, as described in the Examples. It should be noted that the B region and the stalk are regions without significant sequence identity (see, for example, the sequences of pIgR of six species set forth in FIG. 1). Accordingly, it is not generally necessary to test antibodies which bind to the B region to confirm that they do not also bind to the stalk. Antibodies which bind to epitopes spanning the initial pIgR cleavage site can, however, be tested against peptides of the stalk sequence to confirm that the epitope to which the antibodies bind is one that exists in intact pIgR, but that does not bind to the pIgR stalk following the initial cleavage of pIgR. In preferred embodiments, the ligands of the invention do not bind to an epitope within the first 33 amino acids that are cell membrane proximal to the initial pIgR cleavage site. Other suitable techniques for antibody or peptide ligand preparation include selection of libraries of recombinant antibodies/peptides in phage or similar vectors. High affinity antibodies and peptides to the B region can be rapidly isolated by using phage display methods to express recombinant single chain Fv (scFv) fragments or peptide ligands on the phage surface. Briefly, genes encoding the surface protein of a phage are altered so as to allow the insertion of an antibody or peptide gene which is expressed as a fusion protein on the surface of the phage that carries the gene. The phage expressing the desired antibody or peptide ligand can be selectively enriched and isolated by virtue of its affinity/avidity for the B region. The DNA encoding the ligand is packaged in the same phage and which allows the gene encoding the ligand to be isolated. A variety of such methods are amply discussed in the literature and well known to the skilled artisan. See, e.g., Winter et al., Annu. Rev. Immunol. 12:433-455 (1994); Marks et al., J. Mol. Biol. 222:581-597 (1991); Vaughan et al., Nature Biotechnology 14:309-314 (1996), U.S. Pat. Nos. 4,642,334; 4,816,397; 4,816,567; 4,704,692; WO 86/01533; WO 88/09344; WO 89/00999; WO 90/02809; WO 90/04036; EP 0 324 162; EP 0 239 400. In chemical peptide synthesis, a procedure termed “Divide, Couple and Recombine” (DCR) has been used to produce combinatorial peptide libraries. See, Furka et al., Int. J. Pept. Protein Res. 37:487-493 (1991) and Houghten et al., Nature 354:84-86 (1991). As an alternative to DCR, peptide mixtures have also been made by direct coupling of monomer mixtures. See, Rutter et al., U.S. Pat. No. 5,010,175. The use of such methods to produce mixtures of other linear polymers, such as “peptoids”, has been suggested. See, Simon, et al., Proc. Natl. Acad. Sci. USA 89:9367-9371 (1992). In oligonucleotide synthesis, “degenerate” or “wobble” mixtures of oligonucleotide products can be made by, for example, delivery of equimolar mixtures of monomers to an oligonucleotide polymer at specific steps during synthesis. See, Atkinson and Smith, in M Gait, ed., “Oligonucleotide Synthesis. A Practical Approach”, (IRL Press, Oxford, U.K., 1994), pp 35-81. These methods of synthesizing peptides or oligonucleotides provide large numbers of compounds for testing which, if active, can be readily identified. The techniques described above can be used to select antibodies which bind to the B region of humans, or of a non-human species of interest which secretes pIgR. As noted in the Introduction, such animals include birds, such as chickens, turkeys, ducks, and ostriches, farm animals, such as cows, pigs, sheep, rabbits, and goats, primates, such as chimpanzees and rhesus monkeys, animals kept at pets, such as cats and dogs, and laboratory animals such as mice and rats. Suitable peptides can be selected by analogy to the peptides set forth above with respect to the human sequence. Preferably, ligands will be constructed to minimize immunogenicity in the host as, for example, by maximizing the number of autologous (self) sequences present in the ligand. Accordingly, chimeric antibodies having non-xenogenic variable regions are preferred. Particularly preferred are the use of antibodies in which xenogenic portions are excluded, or are essentially limited to the complementarity determining regions as in humanized antibodies. Assaying for Inhibition of Cleavage In preferred embodiments, the ligands binding to the B region inhibit cleavage of the SC from intact pIgR. A number of means exist for determining whether a given ligand inhibits pIgR cleavage. In general, one of skill is aware that inhibition of cleavage can be determined by distinguishing free SC from SC still incorporated into pIgR. Thus, any assay which can determine the rate of formation of free SC can potentially be used as an assay for determining the ability of a ligand to inhibit cleavage. In a simple example, a culture of cells expressing pIgR can be divided into separate samples and the samples cultured under identical conditions. The ligand being tested can then be added to one sample, while an equal amount of the carrier fluid (such as MEM, 5% fetal bovine serum, and the like) is added to the second sample as a control. The supernatant from the two samples can then be run onto affinity columns containing immobilized antibodies to SC or to pIgR, and any bound SC can then be eluted and measured, typically by running a western blot and probing with anti-SC antibodies. A ligand inhibiting cleavage will result in less free SC being present in the test sample compared to the sample to which the carrier alone is added. One can also measure the level of pIgR associated with the pIgR-expressing cells by western blotting. The amount of pIgR associated with the cells will go up as the cleavage of pIgR is inhibited. If desired, the proteins producted by the cells, such as pIgR, can be labeled prior to the study to facilitate detection of the SC captured in the assay. Conveniently, this can be done by providing the cell with cysteine labeled with 35S. An exemplary assay for determining inhibition of cleavage by yet another method, radioactive pulse-chase labeling is set forth in Example 8. This method is preferred since it provides a more direct measurement of cleavage rate. The Major Form of SC Present in an Organ or Tissue, and Methods of Assaying for it SC is secreted by cells lining various organs and tissues. For example, SC is secreted by both the small and the large intestine, and the concentration of proteases diminishes in a gradient proceeding from the small to the large intestine. Additionally, some of the fluid bathing the epithelial cells in the intestine may have originated in other tissues and organs which secrete pIgR, such as the salivary glands and the stomach, which also have different protease concentrations. The most abundant form may also vary according to physiological conditions, With respect to the intestine, for example, the most abundant form may vary in part depending on factors such as how much food is in the intestine, the type of food ingested, the presence of diarrhea or constipation, and the like. The most abundant form may also vary in part according to pathological states, such as inflammation or infection of the organ in question. It is contemplated, however, that the most abundant form of the SC throughout the intestinal tract will be that in which the B region has been digested, and indeed, given the concentration of proteases in the intestinal tract, the B region will generally be somewhat larger than it is in organs in which lower amounts or different kinds of proteases are present. The actual form of the SC which is the most abundant in a particular physiological condition or during a particular pathological state can be determined by assays such as those set forth herein. Similarly, the most abundant form of the SC present in other organs or tissues, such as the lung, vagina, nose, sinuses, uterus, and lacrimal glands of the eye will depend on the particular proteases present in the organ and their concentration, but it is contemplated that the most abundant form will be that in which the B region has been digested. The invention contemplates that compositions of the invention will be tailored to the major species of SC present in the organ of interest. For organs and tissues which can be easily accessed, such as the conjunctiva of the eyes, the passages of the nasal cavity, the vagina, and the anus, the compositions can be applied directly in, for example, eye drops, nasal spray, or vaginal or anal suppositories, respectively. For organs and tissues which are less easily accessible, such as portions of the gastrointestinal tract, the compositions can be administered by cannulation or other methods of direct delivery, or, often more conveniently, by oral administration. Where oral delivery to the small or large intestine is desired, it may be desirable to protect the compositions from degradation in the mouth and stomach. A number of technologies are known in the art for protecting compositions from acid and premature proteolytic digestion. Such technologies include enteric coatings, encapsulation, polymer coats, hydrogel coats, and capsules. See generally, Gennaro et al., eds., Remington's Pharmaceutical Sciences, 17th ed., Mack Publishing Co., Easton, Pa. (1985). A number of means exist for determining the major species of SC present in a tissue or organ of interest. If the invention is to be used with respect to a particular animal species, and the most abundant form of SC present in the organ or tissue of that animal species has not previously been identified, it will be desirable to determine it. For tissues or organs which are not readily accessible, samples from non-human animals can be obtained by a number of means, including sacrificing the animals and extracting the contents of their lungs, intestines or other organs of interest. This is likely the most convenient way to obtain samples from most of the animals raised for meat, such as chickens, turkeys, ducks, sheep, pigs, and cows, since they are killed and their internal organs removed in the course of processing. Samples from humans, primates, and other animals can be obtained in the course of surgery or, often more conveniently, by endoscopy. Samples of fluids from organs or tissues which are readily accessible, such as tears, nasal secretions, and vaginal fluids, can be obtained by simple swabs or other routine sampling procedures. If desired, samples can be taken from both healthy animals and those with particular disease conditions to establish the most abundant form of SC present in the particular organ or tissue in normal individuals and in those with particular disease states. Once a sample of a fluid from a tissue or organ is available, the most abundant form of SC present can be determined by any of a number of means. In general, one of skill will appreciate that the different forms of SC in the sample can be distinguished on the basis of their molecular weight and electrophoretic properties and identified by SC-specific antibodies. Thus, the species of SC can conveniently be distinguished by subjecting the sample to SDS-polyacrylamide gel electrophoresis, followed by western blotting. The identity of the SC species present in the blot can be confirmed by the use of antibodies for portions of the SC expected to be present in all species of SC. For example, the N-terminal portion of the SC would not be expected to be degraded by the proteases which degrade the C-terminal portion (the portion proximal to the site of cleavage from pIgR) and should therefore be present on both freshly cleaved SC and on SC in which the B region has been degraded. An exemplary assay for determining the major species of SC in an organ of is set forth in Example 7. Ligand Binding and Testing Binding (i.e., attachment) of the ligand to the pIgR B region may be at the basolateral or the apical surface. Thus, the ligand can be endocytosed basolaterally or apically, or be subject to apical to basolateral, or basolateral to apical transcytosis. The fate of the ligand, or any element thereof, will vary according to its physico-chemical characteristics. Accordingly, the properties of the ligand may be selected or designed to perform the desired function at the cell surface, within the endosome, or following transcytosis. For example, varying the sensitivity of a ligand to proteolytic or reducing environments can be used to determine the distribution of ligand bound, internalized, or transported across the cell. Where desirable, a ligand may be designed to remain specifically bound to the cell following attachment or transcytosis or, alternatively, to be released into the extracellular milieu on the basolateral side of the cell following apical to basolateral transcytosis. Thus, the properties of any of the various elements of the ligand, including the binding component, biologically active component or linker, may be designed or selected to allow for different degrees of affinity, stability, or activity at different intracellular compartments or surfaces of the cell, as desired. A. Ex Vivo Testing of Ligand Binding In vitro binding of the ligand to the pIgR B region may be conveniently assessed by measuring endocytosis or transcytosis of bound ligand in epithelial cells, and particularly those of humans. “Endocytosis” refers generally to the phenomenon of a cell ingesting material, e.g., by phagocytosis or pinocytosis. Receptor-mediated endocytosis provides an efficient means of causing a cell to ingest material which binds to a cell surface receptor. See, Wu and Wu (1987) J. Biol. Chem. 262:4429-4432; Wagner et al. (1990) Proc. Natl. Acad. Sci. USA 87:3410-3414, and EP-AL 0388 758. Any number of well known methods for assaying endocytosis may be used to assess binding. For example, binding, transcytosis, and internalization assays are described at length in Breitfeld et al. J. Cell Biol. 109:475-486 (1989). Apical endocytosis is conveniently measured by binding a ligand such as a Fab fragment of an antibody to the B region at the apical surface of Madin-Darby canine kidney (MDCK) cells at 4° C., warming to 37° C. for brief periods (0-10 min), and cooling the cells back down to 4° C. Methods of pIgR expression in MDCK cells are well known in the art. Breitfeld et al., Methods in Cell Biology 32:329-337 (1989). Fab remaining on the surface are removed by stripping at pH 2.3. Intracellular Fab are those that remain cell-associated after the stripping, while surface-bound Fab are those removed by the acid wash. Controls for non-specific sticking include using pre-immune Fab and/or MDCK cells that are not transfected with pIgR. Transcytosis can be readily assessed by allowing MDCK cells to bind the Fab at the apical surface at 4° C., warming up to 37° C. for 0-240 min, and then measuring the amount of Fab delivered into the basolateral medium. This basolaterally-delivered Fab is compared to the sum of Fab that remains associated with the cells (intracellular or acid-stripped) and the Fab released back into the apical medium. Alternatively, transcytosis can be assessed by continuously exposing cells to the Fab in the apical medium and measuring accumulation of Fab in the basolateral medium. This method avoids cooling the cells, but does not provide the kinetics of transporting a single cohort of ligand. In both methods, degradation of the Fab can be assessed by running aliquots of the transcytosed Fab on SDS-PAGE and probing a Western blot with appropriate antibodies. Non-specific transport (e.g. due to fluid phase endocytosis and transcytosis, or paracellular leakage between cells) can be controlled for by using MDCK cells that are not transfected with the pIgR and/or pre-immune Fab. B. In Vivo Testing of Ligand Binding Transcytosis in vivo may conveniently be assessed using pathogen-free experimental animals, such as Sprague-Dawley rats. For example, labeled ligand (e.g., radioiodinated antibody) can be administered orally in any of a variety of formulations which have been developed to deliver pharmaceutical agents to the intestine without digestion in the stomach. Alternatively, the ligands can also be delivered surgically by cannulation of the intestine. An exemplary protocol for such an assay is set forth in the Examples, below. As will be understood by those of skill in the art, a “label” is a composition detectable by spectroscopic, photochemical, biochemical, immunochemical, enzymatic, electromagnetic, radiochemical, or chemical means such as fluorescence, chemifluoresence, or chemiluminescence. Apical to basolateral transcytosis can be readily determined by measuring delivery of the ligand into the circulation as determined by the presence of label. The integrity of the ligand recovered from the circulation can be assessed by analyzing the ligand on SDS-polyacrylamide gel electrophoresis. Similar assays can be employed using eye drops to deliver agents to the conjunctiva or lacrimal glands of the eyes, using nose drops to deliver agents to the mucosal surfaces of the nose or nasal sprays to deliver agents to the sinuses, or using vaginal suppositories or washes to deliver agents to the mucosal surfaces of the vagina. C. Antibody Production Monoclonal antibodies may be obtained by various techniques familiar to those skilled in the art. Description of techniques for preparing such monoclonal antibodies may be found in, e.g., Stites, et al. (eds.) BASIC AND CLINICAL IMMUNOLOGY (4TH ED.), Lange Medical Publications, Los Altos, Calif., and references cited therein; Harlow & Lane, supra; Goding, MONOCLONAL ANTIBODIES: PRINCIPLES AND PRACTICE (2D ED.), Academic Press, New York, N.Y. (1986); Kohler & Milstein, Nature 256:495-497 (1975); and particularly (Chowdhury, P. S., et al., Mol. Immunol. 34:9 (1997)), which discusses one method of generating monoclonal antibodies. To immunize with pIgR-coding DNA, pIgR-coding cDNA is introduced into a plasmid so that transcription of the coding sequence is under the control of a promoter such as the CMV promoter. The plasmid is then injected into an animal, either subcutaneously, intradermally, intraperitoneally, etc. As a result, the pIgR cDNA is transcribed in the animal into mRNA, pIgR is translated from the mRNA, the translated protein undergoes proper post-translational modifications and is expressed on the surface of cells which synthesized pIgR. The animal raises antibodies to pIgR and the sera is monitored for antibody titer. Optionally, in addition to the coding region and regulatory elements, the plasmid carries an ampicillin resistance (Amp) gene. The Amp gene is known to have immunostimulatory sequences for Th1 responses necessary for increased antibody production (Sato, et al., Science 273:352-354 (1996)). As described above, in preferred embodiments, the monoclonal antibody is a scFv. Methods of making scFv antibodies have been described. See, Huse, et al., supra; Ward, et al. Nature 341:544-546 (1989); and Vaughan, et al., supra. In brief, mRNA from B-cells is isolated and cDNA is prepared. The cDNA is amplified by well known techniques, such as PCR, with primers specific for the variable regions of heavy and light chains of immunoglobulins. The PCR products are purified by, for example, agarose gel electrophoresis, and the nucleic acid sequences are joined. If a linker peptide is desired, nucleic acid sequences that encode the peptide are inserted between the heavy and light chain nucleic acid sequences. The sequences can be joined by techniques known in the art, such as blunt end ligation, insertion of restriction sites at the ends of the PCR products or by splicing by overlap extension (Chowdhury, et al., Mol. Immunol. 34:9 (1997)). After amplification, the nucleic acid which encodes the scFv is inserted into a vector, again by techniques well known in the art. Preferably, the vector is capable of replicating in prokaryotes and of being expressed in both eukaryotes and prokaryotes. D. Binding Affinity of Antibodies Binding affinity for a target antigen is typically measured or determined by standard antibody-antigen assays, such as competitive assays, saturation assays, or immunoassays such as ELISA or RIA. Such assays can be used to determine the dissociation constant of the antibody. The phrase “dissociation constant” refers to the affinity of an antibody for an antigen. Specificity of binding between an antibody and an antigen exists if the dissociation constant (KD=1/K, where K is the affinity constant) of the antibody is <1 μM, preferably <100 nM, and most preferably <0.1 nM. Antibody molecules will typically have a KD in the lower ranges. KD=[Ab-Ag]/[Ab][Ag] where [Ab] is the concentration at equilibrium of the antibody, [Ag] is the concentration at equilibrium of the antigen and [Ab-Ag] is the concentration at equilibrium of the antibody-antigen complex. Typically, the binding interactions between antigen and antibody include reversible noncovalent associations such as electrostatic attraction, Van der Waals forces and hydrogen bonds. This method of defining binding specificity applies to single heavy and/or light chains, CDRs, fusion proteins or fragments of heavy and/or light chains, that are specific for pIgR if they bind pIgR alone or in combination. The dissociation constant is also described in the art in terms of the constants by which a molecule binds to another (the “Kon”) and dissociates from that molecule (the “Koff”). As reported herein, the scFv of the invention have surprisingly high rates of retrograde transcytosis and basolateral release compared to all other antibodies tested to date. Without being bound by theory, it appears that this may be due in part to a balance of the Kon and Koff rates of the antibodies, by which the Kon rate is sufficient to permit the antibody to bind to pIgR, but the Koff rate is sufficient to permit the release of the antibody at the basolateral surface. Antibodies to the B Region A. Antibodies In one set of preferred embodiments, the ligands of the invention are antibodies which result in surprisingly high rates of retrograde transcytosis of the antibody across pIgR-secreting cells and release on the basolateral surface of these cells. In preferred embodiments, the antibody is a single chain Fv portion of an antibody. In studies with several antibodies, a version of an anti-B region antibody was developed which has proven useful in monitoring binding and transcytosis. This version of the antibody bears the “FLAG®” peptide, a label system commercially available from Sigma (St. Louis, Mo.). Experiments showed that scFvs labeled with the FLAG® peptide and bearing an anti-FLAG antibody could bind to B region of pIgR, undergo apical to basolateral transcytosis and be released into the basolateral medium. The amino acid sequence of an exemplary scFv labeled with the FLAG® epitope (SEQ ID NO:22), an scFv designated 4AF, is set forth in FIG. 5 (the unlabeled scFv, 4A, is the same sequence, minus the FLAG® eptiope). The scFv is labeled with both FLAG® and with an epitope from the myc oncogene. This “FLAGged” form of scFv 4A has a pelb sequence to facilitate secretion of the finished protein when produced in E. coli (as is well known in the art, different leader sequences would be used to facilitate secretion in other organisms), and a 6-histidine tail to facilitate purification using immobilized metal-ion affinity chromatography (“IMAC”). The unboxed “AAA” residues are part of the Not I site engineered in for cloning. Construction of the scFV is described in the Examples. In studies with a second scFv, the primer used to add the FLAG® epitope introduced a non-conserved substitution of a valine for a glutamine at a position within the framework region of the scFv. No statistically significant difference was noted between the tagged and the untagged antibody in assays of retrograde trancytosis or basolateral release. This substitution demonstrated that a non-conservative substition in the framework region did not affect the binding and transport properties of the scFv. This is expected since almost all the antigen recognition and binding properties are considered in the art to be localized in the CDRs. See generally, Kuby, J., Immunology, 3rd Ed., W.H. Freeman & Co., New York (1997). On the basis of these results, it is expected that conservative substitutions in the framework region would be even less likely to affect ligand internalization into the cell, or transcytosis and release into the basolateral medium. Moreover, conservative substitutions can often also be made in the CDRs without adversely affecting the retrograde transcytosis and release at the basolateral surface of the scFvs. The affect of any substitution or substitutions on these properties can readily be tested by standard assays, such as those set forth in the Examples. The particular antibodies tested are scFvs. Persons of skill in the art will recognize that other means of making recombinant antibodies are known in the art which permit making antibodies with the favorable properties of the scFvs tested. For example, scFv sequences can be used to produce disulfide stabilized antibodies, wherein the heavy and light chains of the antibody are associated by disulfide bonds rather than a peptide linker. Such variations on the antibodies are expected to work as do the scFv forms, and are contemplated within the scope of the present invention. Formation of scFv and dsFv antibodies are discussed further below. As noted above, in preferred embodiments of the present invention, the anti-pIgR antibody is a recombinant antibody such as a scFv or a disulfide stabilized Fv antibody. Fv antibodies are typically about 25 kDa and contain a complete antigen-binding site with 3 CDRs per heavy and light chain. If the VH and the VL chain are expressed non-contiguously, the chains of the Fv antibody are typically held together by noncovalent interactions. However, these chains tend to dissociate upon dilution, so methods have been developed to crosslink the chains through glutaraldehyde, intermolecular disulfides, or a peptide linker. In a particularly preferred embodiment, the antibody is a single chain Fv (scFv). The VH and the VL regions of a scFv antibody comprise a single chain which is folded to create an antigen binding site similar to that found in two chain antibodies. Once folded, noncovalent interactions stabilize the single chain antibody. In a more preferred embodiment, the scFv is recombinantly produced. One of skill will realize that conservative variants of the antibodies of the instant invention can be made. Such conservative variants employed in scFv fragments will retain critical amino acid residues necessary for correct folding and stabilizing between the VH and the VL regions. The anti-pIgR antibodies of the invention can be linked to biologically active molecules (sometimes called “effector molecules,” or “EM”) through the EM carboxyl terminus, the EM amino terminus, through an interior amino acid residue of the EM such as cysteine, or any combination thereof. Similarly, the EM can be linked directly to the heavy or light chains or a framework region of the antibody. Linkage can occur through the antibody's amino or carboxyl termini, or through an interior amino acid residue. Further, multiple EM molecules (e.g., any one of from 2-10) can be linked to the anti-pIgR antibody and/or multiple antibodies (e.g., any one of from 2-5) can be linked to an EM. In some embodiments of the present invention, the scFv antibody is directly linked to the EM through the light chain or through the heavy chain. Additionally, scFv antibodies can be linked to the EM via its amino or carboxyl terminus. The scFv can, for example, be engineered to contain a cysteine at the amino or the carboxy terminus to permit coupling to a compound through a sulfhydryl-reactive linker. While the VH and VL regions of some antibody embodiments can be directly joined together, one of skill will appreciate that the regions may be separated by a peptide linker consisting of one or more amino acids. Peptide linkers and their use are well-known in the art. See, e.g., Huston, et al., Proc. Nat'l Acad. Sci. USA 8:5879 (1988); Bird, et al., Science 242:4236 (1988); Glockshuber, et al., Biochemistry 29:1362 (1990); U.S. Pat. No. 4,946,778, U.S. Pat. No. 5,132,405 and Stemmer, et al., Biotechniques 14:256-265 (1993), all incorporated herein by reference. Generally the peptide linker will have no specific biological activity other than to join the regions or to preserve some minimum distance or other spatial relationship between them. However, the constituent amino acids of the peptide linker may be selected to influence some property of the molecule such as the folding, net charge, or hydrophobicity. Single chain Fv (scFv) antibodies optionally include a peptide linker of no more than 50 amino acids, generally no more than 40 amino acids, preferably no more than 30 amino acids, and more preferably no more than 20 amino acids in length. In some embodiments, the peptide linker is the sequence is Gly-Gly-Gly-Ser, Gly-Gly-Gly-Ser-Gly-Gly-Gly (optionally, an additional Gly can be on either or both ends), or Gly-Gly-Gly-Gly-Ser or a concatamer of this sequence, and will preferably comprise 2, 3, 4, 5, or 6 copies of this sequence. It should be noted that glycine is generally preferred in peptide linkers because it is flexible, does not have a side group expected to interfere with the intended biological activity of the linked molecules, and under physiological conditions does not bear a charge. However, it is to be appreciated that some amino acid substitutions within the linker can be made. For example, a valine can be substituted for a glycine. B. Epitope Binding of Anti-B Region Antibodies As set forth in the Examples, the epitopes to which phage displaying scFv from a human library bound were mapped using a series of 15-residue peptides. Both human pIgR and rat pIgR sequences were used for mapping. The results of the ELISAs revealed that the scFv bound primarily to regions on the N-terminal side of the major cleavage site. For example, as shown in FIG. 3, scFv 4A bound to the epitope defined by the sequence QDPRLF (SEQ ID NO:10) in human pIgR (residues 600 to 605 of the human sequence as set forth in SWISS-PROT) and to the epitope defined by the sequence LDPRLF in rat pIgR (SEQ ID NO:11) (residues 605-610 of the rat pIgR sequence). Although not tested directly, it appears likely that the “Q” in the human sequence and the “L” in the rat sequence may not be necessary and that the antibody will bind to the epitope defined by the amino acids DPRLF. As further shown in FIG. 3, the epitope LDPRFL of rat pIgR was also bound by antibody 5D, which also bound to the epitope defined by the sequence KAIQDPRLF (SEQ ID NO:12) of human pIgR. ScFv 2E bound to the epitope defined by the sequence LDPRLFADERI (SEQ ID NO:13) of rat pIgR. ScFv 2H bound to the epitope defined by the sequence DENKANLDPRLF (SEQ ID NO:14). ScFv IF bound to the epitope defined by the sequence RLFADERI (SEQ ID NO:15). ScFvs IC, 7H, and 6B all bound to the epitope defined by the sequence LDPRLFADE (SEQ ID NO:16). Since the peptides tested were “staggered” by three residues, the more peptides the antibodies were tested against, the more it was possible to map the precise epitope to which the antibody bound. C. Immunoassays The antibodies can be detected and/or quantified using any of a number of well recognized immunological binding assays (see, e.g., U.S. Pat. Nos. 4,366,241; 4,376,110; 4,517,288; and 4,837,168). For a review of general immunoassays, see also METHODS IN CELL BIOLOGY, VOL. 37, Asai, ed. Academic Press, Inc. New York (1993); BASIC AND CLINICAL IMMUNOLOGY 7TH EDITION, Stites & Terr, eds. (1991). Immunological binding assays (or immunoassays) typically utilize a ligand (e.g., pIgR) to specifically bind to and often immobilize an antibody. The antibodies employed in immunoassays of the present invention are discussed in greater detail supra. Immunoassays also often utilize a labeling agent to specifically bind to and label the binding complex formed by the ligand and the antibody. The labeling agent may itself be one of the moieties comprising the antibody/analyte complex, i.e., the anti-pIgR antibody. Alternatively, the labeling agent may be a third moiety, such as another antibody, that specifically binds to the antibody/pIgR protein complex. In one aspect, a competitive assay is contemplated wherein the labeling agent is a second anti-pIgR antibody bearing a label. The two antibodies then compete for binding to the immobilized pIgR. Alternatively, in a non-competitive format, the pIgR antibody lacks a label, but a second antibody specific to antibodies of the species from which the anti-pIgR antibody is derived, e.g., murine, and which binds the anti-pIgR antibody, is labeled. In particular, competitive assays as just described can be used to see if an antibody binds to the same epitope as the scFvs discussed above. Typically, columns are prepared with a pIgR protein or a portion thereof, such as residues 600-605 of the human pIgR sequence, immobilized on the surface. The first column is contacted with a quantity of the antibody being tested (the “test antibody”) and is then contacted with a known amount of an scFv which is known to bind to the epitope in question (the “known antibody”) has been detectably labeled. The pIgR protein or peptide on the second column is contacted with the same amount of known antibody as used on the first column, but without first being contacted with the known antibody, and the amount of known antibody present on each column is determined. If the amounts of known antibody present on both columns are the same, then the test antibody is considered not to bind to the same epitope as does the known antibody or to inhibit the binding of the known antibody. If the amounts of known antibody bound on the column which was contacted by known antibody but not the test antibody is higher than than the amount of known antibody bound to the column which was first contacted with the test antibody, then the test antibody is considered to bind to the same epitope as does the known antibody or to inhibit the binding of the known antibody to its epitope. Other proteins, such as Protein A or Protein G, may also be used as the label agent. For example, tests have shown that scFv antibodies of the invention bind Protein A. These proteins are normal constituents of the cell walls of streptococcal bacteria. Other proteins known in the art, such as Protein L, may also be used. These proteins exhibit a strong non-immunogenic reactivity with immunoglobulin constant regions from a variety of species (see, generally Kronval, et al., J. Immunol. 111: 1401-1406 (1973); and Akerstrom, et al., J. Immunol. 135:2589-2542 (1985)). Throughout the assays, incubation and/or washing steps may be required after each combination of reagents. Incubation steps can vary from about 5 seconds to several hours, preferably from about 5 minutes to about 24 hours. However, the incubation time will depend upon the assay format, antibody, volume of solution, concentrations, and the like. Usually, the assays will be carried out at ambient temperature, although they can be conducted over a range of temperatures, such as 10° C. to 40° C. While the details of the immunoassays of the present invention may vary with the particular format employed, the method of detecting anti-pIgR antibodies in a sample containing the antibodies generally comprises the steps of contacting the sample with an antibody which specifically reacts, under immunologically reactive conditions, to the pIgR/antibody complex. Assaying Antibody Transcytosis and Release Binding (i.e., attachment) of the ligands of the invention to pIgR is typically at the apical surface. Thus, the ligand is typically endocytosed apically and subject to apical to basolateral (retrograde) transcytosis. The fate of the ligand, or any element thereof, will vary according to its physico-chemical characteristics. Accordingly, the properties of the ligand may be selected or designed to perform the desired function following transcytosis. For example, varying the sensitivity of a ligand to proteolytic or reducing environments can be used to determine the distribution of ligand bound, internalized, or transported across the cell. Thus, the properties of any of the various elements of the ligand, including the binding component, biologically active component or linker, may be designed or selected to allow for different degrees of affinity, stability, or activity at different intracellular compartments or surfaces of the cell, as desired. As noted in the Introduction, the antibodies of the invention bind to pIgR and undergo reverse transcytosis from the apical surface of a pIgR-secreting epithelial cell and are released into the extracellular fluid at the basolateral side of the cell at rates that are at least twice that of the polyclonal antibodies developed by Brietfield et al., and which are at least twice that of all other polyclonal and scFv antibodies tested to date when measured, for instance, in standard assays. An exemplary assay by which transcytosis and release can be measured is set forth in the Examples, below. Studies with radiolabeled scFv tested by this assay have demonstrated that over a twelve hour period, as much as 15% of the starting amount of antibody introduced into an in vitro culture underwent reverse transcytosis and was released into the medium in contact with the basolateral surface of the pIgR-secreting cells in the culture. Tests with an scFv conjugated to a second antibody (in this case, an antibody against a FLAG peptide expressed in frame with the scFv, as explained in the Examples) following the same assay procedure showed that this complex similarly underwent reverse transcytosis and was released into the medium in contact with the basolateral surface of the pIgR-secreting cells in the culture at rates significantly higher than those reported by Breitfeld et al. for their uncomplexed antibodies. Production of Immunoconjugates Immunoconjugates include, but are not limited to, molecules in which there is a covalent linkage of a therapeutic agent to an antibody. A therapeutic agent is an agent with a particular biological activity directed against a particular target molecule or a cell bearing a target molecule. One of skill in the art will appreciate that therapeutic agents may include various drugs such as vinblastine, daunomycin and the like, encapsulating agents, (e.g., liposomes) which themselves contain pharmacological compositions, radioactive agents such as 125I, 32P, 14C, 3H and 35S and other labels, target moieties and ligands. The choice of a particular therapeutic agent depends on the particular target molecule or cell and the biological effect is desired to evoke. Thus, for example, a therapeutic agent may be used to ameliorate a symptom or a cause of a disease. Or, compositions of the invention may comprise a diagnostic agent whose such as a radiolabel may be used to visualize circulation or other aspects of a pratitioner's concern. With the therapeutic agents and antibodies herein provided, one of skill can readily construct a variety of clones containing functionally equivalent nucleic acids, such as nucleic acids which differ in sequence but which encode the antibody sequence. Thus, the present invention provides nucleic acids encoding antibodies and conjugates and fusion proteins thereof. A. Recombinant Methods The nucleic acid sequences of the present invention can be prepared by any suitable method including, for example, cloning of appropriate sequences or by direct chemical synthesis by methods such as the phosphotriester method of Narang, et al., Meth. Enzymol. 68:90-99 (1979); the phosphodiester method of Brown, et al., Meth. Enzymol. 68:109-151 (1979); the diethylphosphoramidite method of Beaucage, et al., Tetra. Lett. 22:1859-1862 (1981); the solid phase phosphoramidite triester method described by Beaucage & Caruthers, Tetra. Letts. 22(20):1859-1862 (1981), e.g., using an automated synthesizer as described in, for example, Needham-VanDevanter, et al. Nucl. Acids Res. 12:6159-6168 (1984); and, the solid support method of U.S. Pat. No. 4,458,066. Chemical synthesis produces a-single stranded oligonucleotide. This may be converted into double stranded DNA by hybridization with a complementary sequence, or by polymerization with a DNA polymerase using the single strand as a template. One of skill would recognize that while chemical synthesis of DNA is limited to sequences of about 100 bases, longer sequences may be obtained by the ligation of shorter sequences. In a preferred embodiment, the nucleic acid sequences of this invention are prepared by cloning techniques. Examples of appropriate cloning and sequencing techniques, and instructions sufficient to direct persons of skill through many cloning exercises are found in Sambrook, et al., MOLECULAR CLONING: A LABORATORY MANUAL (2ND ED.), Vols. 1-3, Cold Spring Harbor Laboratory (1989)), Berger and Kimmel (eds.), GUIDE TO MOLECULAR CLONING TECHNIQUES, Academic Press, Inc., San Diego Calif. (1987)), or Ausubel, et al. (eds.), CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, Greene Publishing and Wiley-Interscience, NY (1987). Product information from manufacturers of biological reagents and experimental equipment also provide useful information. Such manufacturers include the SIGMA chemical company (Saint Louis, Mo.), R&D systems (Minneapolis, Minn.), Pharmacia LKB Biotechnology (Piscataway, N.J.), CLONTECH Laboratories, Inc. (Palo Alto, Calif.), Chem Genes Corp., Aldrich Chemical Company (Milwaukee, Wis.), Glen Research, Inc., GIBCO BRL Life Technologies, Inc. (Gaithersberg, Md.), Fluka Chemica-Biochemika Analytika (Fluka Chemie AG, Buchs, Switzerland), Invitrogen, San Diego, Calif., and Applied Biosystems (Foster City, Calif.), as well as many other commercial sources known to one of skill. Nucleic acids encoding anti-pIgR antibodies can be modified. Modification by site-directed mutagenesis is well known in the art. Nucleic acids encoding anti-pIgR antibodies can be amplified by in vitro methods. Amplification methods include the polymerase chain reaction (PCR), the ligase chain reaction (LCR), the transcription-based amplification system (TAS), the self-sustained sequence replication system (3SR). A wide variety of cloning methods, host cells, and in vitro amplification methodologies are well known to persons of skill. In a preferred embodiment, immunoconjugates are prepared by inserting the cDNA which encodes an anti-pIgR scFv antibody into a vector which comprises the cDNA encoding a biologically active component (sometimes called an “effector molecule,” or “EM”). The insertion is made so that the scFv and the EM are read in frame, that is in one continuous polypeptide which contains a functional Fv region and a functional EM region. Once the nucleic acids encoding an anti-pIgR antibody of the present invention or a conjugate employing such an antibody are isolated and cloned, one may express the desired protein in recombinantly engineered cells, such as bacteria, plant, yeast, insect and mammalian cells. It is expected that those of skill in the art are knowledgeable in the numerous expression systems available for expression of proteins including E. coli, other bacterial hosts, yeast, and various higher eucaryotic cells such as the COS, CHO, HeLa and myeloma cell lines. No attempt to describe in detail the various methods known for the expression of proteins in prokaryotes or eukaryotes will be made. In brief, the expression of natural or synthetic nucleic acids encoding the isolated proteins of the invention will typically be achieved by operably linking the DNA or cDNA to a promoter (which is either constitutive or inducible), followed by incorporation into an expression cassette. The cassettes can be suitable for replication and integration in either prokaryotes or eukaryotes. Typical expression cassettes contain transcription and translation terminators, initiation sequences, and promoters useful for regulation of the expression of the DNA encoding the protein. To obtain high level expression of a cloned gene, it is desirable to construct expression cassettes which contain, at the minimum, a strong promoter to direct transcription, a ribosome binding site for translational initiation, and a transcription/translation terminator. For E. coli, this includes a promoter such as the T7, trp, lac, or lambda promoters, a ribosome binding site and preferably a transcription termination signal. For eukaryotic cells, the control sequences can include a promoter and preferably an enhancer derived from immunoglobulin genes, SV40, cytomegalovirus, and a polyadenylation sequence, and may include splice donor and acceptor sequences. The cassettes of the invention can be transferred into the chosen host cell by well-known methods such as calcium chloride transformation or electroporation for E. coli and calcium phosphate treatment, electroporation or lipofection for mammalian cells. Cells transformed by the cassettes can be selected by resistance to antibiotics conferred by genes contained in the cassettes, such as the amp, gpt, neo and hyg genes. One of skill would recognize that modifications can be made to a nucleic acid encoding a polypeptide of the present invention (i.e., anti-pIgR antibody, or an immunoconjugate formed using an anit-pIgR antibody) without diminishing its biological activity. Some modifications may be made to facilitate the cloning, expression, or incorporation of the targeting molecule into a fusion protein. Such modifications are well known to those of skill in the art and include, for example, a methionine added at the amino terminus to provide an initiation site, or additional amino acids (e.g., poly His) placed on either terminus to create conveniently located restriction sites or termination codons or purification sequences. In addition to recombinant methods, antibodies and conjugates employing antibodies of the present invention can also be constructed in whole or in part using standard peptide synthesis. Solid phase synthesis of the polypeptides of the present invention of less than about 50 amino acids in length may be accomplished by attaching the C-terminal amino acid of the sequence to an insoluble support followed by sequential addition of the remaining amino acids in the sequence. Techniques for solid phase synthesis are described by Barany & Merrifield, THE PEPTIDES: ANALYSIS, SYNTHESIS, BIOLOGY. VOL. 2: SPECIAL METHODS IN PEPTIDE SYNTHESIS, PART A. pp. 3-284; Merrifield, et al. J. Am. Chem. Soc. 85:2149-2156 (1963), and Stewart, et al., SOLID PHASE PEPTIDE SYNTHESIS, 2ND ED., Pierce Chem. Co., Rockford, Ill. (1984). Proteins of greater length may be synthesized by condensation of the amino and carboxyl termini of shorter fragments. Methods of forming peptide bonds by activation of a carboxyl terminal end (e.g., by the use of the coupling reagent N,N′-dicycylohexylcarbodiimide) are known to those of skill. B. Purification Once expressed, the recombinant immunoconjugates, antibodies, and/or effector molecules of the present invention can be purified according to standard procedures of the art, including ammonium sulfate precipitation, affinity columns, column chromatography, and the like (see, generally, R. Scopes, PROTEIN PURIFICATION, Springer-Verlag, N.Y. (1982)). Substantially pure compositions of at least about 90 to 95% homogeneity are preferred, and 98 to 99% or more homogeneity are most preferred for pharmaceutical uses. Once purified, partially or to homogeneity as desired, if to be used therapeutically, the polypeptides should be substantially free of endotoxin. Methods for expression of single chain antibodies and/or refolding to an appropriate active form, including single chain antibodies, from bacteria such as E. coli have been described and are well-known and are applicable to the antibodies of this invention. See, Buchner, et al., Anal. Biochem. 205:263-270 (1992); Pluckthun, Biotechnology 9:545 (1991); Huse, et al., Science 246:1275 (1989) and Ward, et al., Nature 341:544 (1989), all incorporated by reference herein. Often, functional heterologous proteins from E. coli or other bacteria are isolated from inclusion bodies and require solubilization using strong denaturants, and subsequent refolding. During the solubilization step, as is well-known in the art, a reducing agent must be present to separate disulfide bonds. An exemplary buffer with a reducing agent is: 0.1 M Tris pH 8, 6 M guanidine, 2 mM EDTA, 0.3 M DTE (dithioerythritol). Reoxidation of the disulfide bonds can occur in the presence of low molecular weight thiol reagents in reduced and oxidized form, as described in Saxena, et al., Biochemistry 9: 5015-5021 (1970), incorporated by reference herein, and especially described by Buchner, et al., supra. Renaturation is typically accomplished by dilution (e.g., 100-fold) of the denatured and reduced protein into refolding buffer. An exemplary buffer is 0.1 M Tris, pH 8.0, 0.5 M L-arginine, 8 mM oxidized glutathione (GSSG), and 2 mM EDTA. As a modification to the two chain antibody purification protocol, the heavy and light chain regions are separately solubilized and reduced and then combined in the refolding solution. A preferred yield is obtained when these two proteins are mixed in a molar ratio such that a 5 fold molar excess of one protein over the other is not exceeded. It is desirable to add excess oxidized glutathione or other oxidizing low molecular weight compounds to the refolding solution after the redox-shuffling is completed. Egress of the Ligand from the Endosome A number of methods well known to the skilled artisan may be used to transport ligand, or any portion thereof, out of the endosome. A poly-L-lysine/nucleic acid complex bound to a ligand which binds specifically to the B region can be used for efficient transfection. Methods of complexing nucleic acids to antibodies are known in the art. See, e.g., Ferkol et al., J. Clin. Invest., 92:2394-2400 (1993); and Ferkol et al., J. Clin. Invest., 95:493-502 (1995). In another approach, poly-L-lysine can be linked, such as by genetic fusion or chemical linkers, to a ligand that binds specifically to the pIgR B region. In turn, this complex can be linked to defective adenovirus. Curiel and co-workers have demonstrated that naked plasmid DNA bound electrostatically to poly-L-lysine or poly-L-lysine-transferrin which has been linked to defective adenovirus mutants can be delivered to cells with transfection efficiencies approaching 90%. The adenovirus-poly-L-lysine-DNA conjugate binds to the normal adenovirus receptor and is subsequently internalized by receptor-mediated endocytosis. This approach has been used to obtain as much as a 1000-fold increase in expression of gene therapy vectors. Herpes viruses have similar properties. Curiel et al. (1991) Proc Natl Acad Sci USA 88:8850-8854; Cotten et al. (1992) Proc Natl Acad Sci USA 89:6094-6098; Curiel et al. (1992) Hum Gene Ther 3:147-154; Wagner et al. (1992) Proc Natl Acad Sci USA 89:6099-6103; Michael et al. (1993) J Biol Chem 268:6866-6869; Curiel et al. (1992) Am J Respir Cell Mol Biol 6:247-252, and Harris et al. (1993) Am J Respir Cell Mol Biol 9:441-447); Gao et al. (1993) Hum. Gene Ther. 4:17-24; Curiel et al. U.S. patent application Ser. No. 07/768,039. In yet another approach using influenza virus, a hydrophobic peptide in the hemagglutinin can act as a fusion peptide at low pH to effect fusion of the virus with the membrane of the endosome and delivering the virus into the cytoplasm. This peptide has been used in transferrin/peptide/poly-L-lysine/DNA complexes for gene transfer using the transferrin receptor and substantially improved the efficiency of expression. Wagner et al., Proc. Natl. Acad. Sci USA 89:7934-7938 (1992). This peptide can be engineered into a ligand for transport of the ligand, or a portion thereof, out of the endosome. A further approach may employ ricin A. Ricin A chain is capable of penetrating out of endosome and into the cytosol. Beaumell et al., J. Biol. Chem. 268:23661-23669 (1993). A ligand of the present invention may be linked to ricin A, such as by genetic fusion or chemical linkers. EXAMPLES The following examples are offered to illustrate, but not to limit the claimed invention. Example 1 This Example describes a method of producing and assaying for antibodies and Fab fragments which specifically bind to the rabbit pIgR stalk region. Among other things, such antibodies can be used as negative controls in assays for determining that ligands bind to the B region rather than to the pIgR stalk. The membrane-spanning segment of the rabbit pIgR begins at the Valine residue at position 630. The sequence of the twenty three extracellular residues of the rabbit pIgR that precede the membrane-spanning segment is: 607-AspProAlaSerGlySerArgAlaSerValAsp AlaSerSerAlaSerGlyGlnSerGlySerAlaLys-629 (SEQ ID NO:7). Two peptides were synthesized (Immuno-Dynamics, Inc., La Jolla, Calif.) representing the extracellular, membrane proximal 16 and 23 amino acids of pIgR. A C-terminal cysteine was added for conjugation purposes. Peptide sequences (in single letter code) were: DPA SGS RAS VDA SSA SGQ SGS AKC (SEQ ID NO:8) for the primary peptide; and the subsequence peptide: ASV DAS SAS GQS GSA KC (SEQ ID NO:9). Half of each amount of peptide was conjugated to keyhole limpet hemocyanin (KLH) (by Immuno-Dynamics, Inc). The KLH-conjugated peptides were sent to Lampire Biological Laboratories (Pipersville, Pa.) for production of chicken antibodies in two chickens per peptide. Lampire's standard protocol for chicken immunization was followed by collection of pre-immune eggs and a pre-immune test bleed; intramuscular injection of 2 mg of peptide with Freund's complete suspension at project initiation; intramuscular injection of 0.5 mg of peptide with Freund's incomplete suspension week 1; intramuscular injection of 0.25 mg of peptide with Freund's incomplete suspension week 2; rest week 3; intramuscular injection of 0.25 mg of peptide with Freund's incomplete suspension week 4; rest week 5, and test bleed week 6. Daily egg collection began around week 6 and monthly test bleeds were collected. Eggs were delivered monthly. Upon arrival, egg yolks were carefully separated from egg whites, and stored at 4° C. in 50-80 mls of basic buffer (0.01M sodium phosphate pH 7.5, 0.1M NaCl, 0.01% azide) per egg yolk until processed for extracting chicken antibody (“IgY”). IgY was extracted from batches of stored egg yolks by a series of PEG precipitations followed by a series of ammonium sulfate precipitations, according to the method of Polson et al. Immunol Commun. 9:475 (1980)). Briefly, solid PEG (polyethylene glycol, MW 8000) was added to yolks in basic buffer to 3.5% by weight of PEG to volume of diluted yolk, and stirred at room temperature until dissolved. The solution was centrifuged at 14,000 g for 10 min at 20° C. and decanted through a funnel containing a loose layer of absorbent cotton gauze. More PEG was added to the clear filtrate for a final PEG concentration of 12% to precipitate the IgA. After sedimenting the precipitate by centrifuging at 14,000 g for 10 min at 20° C., the precipitate was dissolved in 60 ml of basic buffer per yolk and an equal volume of 24% PEG in basic buffer was added to reform the precipitate. The precipitate was centrifuged twice more at 14,000 g for 10 min at 20° C. to remove all residual PEG solution. Pellets were dissolved in 30 mls of basic buffer per egg yolk, and the protein was precipitated in 50% saturated (NH4)2SO4 by slowly adding an equal volume of saturated (NH4)2SO4. and by stirring overnight at 4° C. The precipitate was centrifuged at 14,000 g for 10 min at 4° C. and the pellet was washed in an equal volume of cold 50% (NH4)2SO4. The precipitate was centrifuged again at 14,000 g for 10 min at 4° C., dissolved in PBS without calcium or magnesium, pH 7.5, and dialyzed extensively in PBS to remove all (NH4)2SO4. Purity of the IgY preparation was confirmed by SDS-PAGE (approx. 90-95%), and quantitation of IgY was estimated by measuring the absorbance at 280 nm and using an extinction coefficient of 1.3. Affinity purification of IgY from chickens injected with the primary peptide of SEQ ID NO:7 was accomplished by first covalently linking the peptide to SULFOLINK coupling gel (Pierce Chemical Company), which allows binding specifically to sulfhydryl groups such as that on the C-terminal cysteine of the peptide. A 3 ml column was made with 3 mg of peptide according to the product instructions. Briefly, a 3 ml column was equilibrated with 6 column volumes of 50 mM Tris, 5 mM EDTA, pH 8.5, and then 3 mg of the primary peptide SEQ ID NO:7 in 3 ml 50 mM Tris, 5 mM EDTA pH 8.5 were added to the column for mixing at room temperature for 15 min. The column gel and peptide were incubated for another 30 min without mixing. The peptide buffer was drained off the gel and saved for later testing to confirm coupling efficiency using Ellman's reagent (DTNB (5,5′-dithiobis(2-nitrobenzoic acid), Pierce Chemical Company) which detects sulfhydryl groups. The primary peptide SEQ ID NO:7 does not contain any aromatic amino acid groups and could not be detected spectrophotometrically or by standard protein assay techniques, such as by Bradford analysis. Using Ellman's reagent according to the product instructions for comparison of an aliquot of peptide solution before and after binding to the gel, confirmed 100% binding efficiency. The gel column was washed with 3 column volumes of 50 mM Tris, 5 mM EDTA pH 8.5 before blocking nonspecific binding sites with 3 ml of cysteine solution in 50 mM Tris, 5 mM EDTA pH 8.5 for 15 min mixing at room temperature followed by 30 minutes without mixing. The column was drained, and washed with 16 column volumes of 1M NaCl and then with 16 column volumes of degassed 0.05% sodium azide. IgY was affinity purified on this peptide-linked SULFOLINK gel according to a modified version of Rosol et al. Veterinary Immunology and Immunopathology, 35:321-337, 1993. Once at room temperature, the column was washed with 10 column volumes of PBS. IgY was recycled on the column for 2 hours. The column was then washed with 10 column volumes of PBS followed by 10 column volumes of phosphate buffered saline (PBS) with 0.5M NaCl. Peptide-specific IgY was eluted with 500 mM glycine pH 2.5 and neutralized with 1M Tris pH 9.5. A UV spectrophotometer and graphing apparatus were used to follow the washing and elution of protein off the column. Samples with a signal at OD280 nm were concentrated in a centriprep 30 (Amicon) to a volume of 500-600 μl. Fab fragments (known in this context as “Yab fragments” since they are derived from IgY) were made from affinity purified IgY incubated with immobilized pepsin (Pierce Chemical Company) according to product instructions and modified from the method of Akita and Nakai. Journal of Immunological Methods. 162:155-164, 1993. Pepsin slurry was washed twice with 16 times the volume of 50 mM sodium acetate buffer pH 4.2, and resuspended in twice the volume of sodium acetate buffer. Affinity purified IgY was incubated with the immobilized pepsin at 37° C. and mixed for 5 hours. One molar Tris-HCl pH 8.0 was added to give a final pH of 7.5. The pepsin mixture was centrifuged at 1000 g for 5 min and the supernatant containing the fragments was added to a CENTRICON 10 filter (Amicon) to remove small Fc fragments. Complete cleavage was confirmed by SDS-PAGE. Chicken serum from successive test bleeds and IgY extracted from batches of pooled egg yolks were tested by ELISA to confirm recognition of the peptide. Affinity purified IgY and Fab′ fragments (“Yab′”) were tested for their ability to recognize intact pIgR by western blot. Cell lysates were made from Madin-Darby canine kidney (MDCK) cells and MDCK cells transfected with rabbit pIgR (“pWe”), according to the method of Breitfeld et al. (Methods in Cell Biology 32:329-337 (1989)) using 10% NP40 lysis buffer containing 1 μg/ml of protease inhibitors and phenylmethylsulfonyl fluoride (PMSF). Cell lysates were run on a 10% gel under reducing conditions and transferred onto a PVDF (polyvinyldifluoride) membrane (Millipore, Bedford, Mass.). A mouse monoclonal antibody to the cytoplasmic portion of pIgR, SC166 (Solari et al., Cell, 36:61-71 (1984)), was used as a positive control antibody, and IgY isolated from pre-Immune yolks was used as a negative control. HRP-conjugated rabbit anti-chicken IgY (Jackson Immunochemicals) and HRP-conjugated rabbit anti-mouse (Biorad) were used as secondary antibodies. IgY from a chicken injected with the primary peptide and IgY from a chicken injected with the subsequence peptide recognized intact pIgR, but IgY from one of the chickens injected with the subsequence antibody did not. Immunofluorescence studies of IgY and Fab fragments (from chickens injected with the primary peptide) with MDCK and pWe cells grown on coverslips, fixed with 4% paraformaldehyde and permeabilized with saponin showed more specific staining of the pIgR-transfected cells (FITC-conjugated rabbit anti-chicken and anti-mouse antibodies obtained from Jackson Immunochemicals). A cell ELISA (modified from M Hahne et al., Journal of Cell Biology. 121:655-64, 1993) on fixed and permeabilized cells showed Fab fragment staining 5-fold greater with pWe cells than MDCK cells. These data demonstrate that we successfully raised polyclonal antibodies against the rabbit pIgR stalk peptide and that they recognize intact pIgR. Example 2 Antibodies directed to desired portions of the pIgR B region can be generated by using peptides of the B region following art recognized techniques, such as those set forth in the preceding Example. Suitable peptides of portions of the B region can be selected from, for example, the sequences shown in FIG. 1. With reference to FIG. 2, suitable examples include: Lys577-Arg603; Lys577-Glu607; Ser574-Arg603; Ser574-Glu607; Val560-Arg603; Val560-Glu607; Cys544-Arg603; and, Cys544-Glu607. Antibodies raised against these or other peptides are then tested against the most abundant form of SC present in the intestine of the animal species of interest; any antibodies that bind to that form of SC are not within the scope of the ligands of the present invention. Example 3 This Example describes selection of human recombinant single chain variable region fragment (scFv) antibodies by phage display. Selection of scFv by phage display requires a soluble biotinylated antigen or antigen immobilized on a solid support. Because scFv selected by phage display tend to be low affinity binders and because the soluble antigen may allow selection of higher affinity scFv (R Schier et al., J. Mol. Biol. 255:28-43, 1996), the selection approach with soluble antigen is chosen. The pIgR B region peptide corresponding to 23 amino acids of the putative B region of the rabbit pIgR is conjugated to biotin via the sulfhydryl group of the cysteine residue using biotin-BMCC ((1-Biotinamido-4-(4′[maleimidomethyl]cyclohexane-carboxamido)butane) (Pierce Chemical Company, Rockford, Ill.) based on the method described in the product instructions. To ensure that the peptide does not dimerize via the sulfhydryl groups, the peptide is first reduced with 1% sodium borohydride in 0.1M Tris, 5 mM EDTA pH 8.0. The pH of the solution is lowered to pH 5 by adding 1N HCl. Once the solution finishes fizzing, 1M Tris is added back to reach pH 7.0. A 8.5 mM biotin-BMCC solution is prepared by dissolving the biotinylation reagent in DMSO. A 5-fold molar excess of biotin-BMCC is added to the reduced peptide and incubated overnight at 4° C. The biotinylated peptide is separated from free biotin by HPLC with a C18 column with a gradient ranging from 10 to 50% CH3CN over 30 min, with UV detection at 215 nm. Mass spectrometry by electrospray and LSIMS (liquid secondary ion mass spectrometry) identifies the correct peak corresponding to the biotinylated peptide. The biotinylated primary peptide is incubated with a phage library encoding a large number of different human scFv (approx. 1010). This phage library is prepared as previously described (Marks et al., J. Mol. Biol. 222:581-97, 1991; Marks et al., Bio/Technology 10;779-783, 1992; Marks et al., Bio/Technology 11:1145-1149, 1993; Griffiths et al., EMBO J. 12:725-734, 1993). A total of four rounds of selection, phagemid rescue and expansion in Escherichia coli suppressor strain TG-1 are performed as described in Marks et al. (J. Mol. Biol. 222:581-97, 1991) with the following modifications. The phage library used is known to contain several streptavidin binders, so the first three rounds of selection include a preclearing step with two 30 min incubations of the phage with streptavidin agarose (Sigma). The phage are then incubated with 5 μg of biotinylated primary peptide for 1 hour. To bind the biotinylated peptide with the attached phage, the peptide-phage solution is incubated with avidin magnetic beads on the first and third rounds for 15 and 5 minutes, respectively, and with streptavidin magnetic beads on the second and fourth rounds for 10 and 5 minutes, respectively. Rescued phage from the fourth round of selection are infected into Escherichia coli non-suppressor strain HB2151, and individual phagemid clones are induced to produce soluble scFv fragments with IPTG as described in Marks et al. (J. Mol. Biol. 222:581-97, ((1991)). Bacterial supernatants from the individual clones are analyzed for expression of soluble scFv fragments in a dot blot assay and for binding to biotinylated primary peptide in an ELISA assay (Finnern et al., Clin. Exp. Immunol. 102:566-574, 1995). The ELISA assay, however, is modified in the following manner: 96-well microwell plates (Immulon-4) are coated with avidin (10 μg/ml in phosphate buffered saline (PBS)) overnight at 4° C., washed 3 times with PBS, blocked with 2% milk in PBS and bound with biotinylated primary peptide (5 μg/ml in PBS). TMB (3,3′,5,5′ tetramethylbenzidine) solution (Kirkegaard and Perry) is used as substrate (100 μl/well), and the reaction is stopped with 0.18M H2SO4 before reading the color reaction in an ELISA reader at a wavelength of 450 nm. Dot blot analysis shows that 66% of the 96 selected colonies of HB2151 infected with phage rescued from the fourth round of selection produces scFv. ELISA assay shows that 43 of the 96 colonies produces scFv that binds to the peptide. The diversity of all positive clones is determined by PCR screening. The scFv insert of the heavy and light chain is first amplified with the primers LMB3 and fd-Seq1 (Marks et al., J. Mol. Biol. 222:581-97, 1991), and then digested with the restriction enzyme BstN1. Clones with different DNA fingerprint patterns are sequenced using a SequiTherm Long-Read cycle sequencing kit (Epicentre Technologies) and a Licor machine. Five unique sequences are identified. To obtain large amounts of purified scFv for further characterization and use, the five unique scFv are subcloned into the expression vector pUC119 Sfi-NotmycHis, which adds a hexa-histidine tag at the C-terminal end of the scFv (Schier et al., J. Mol. Biol., 255:28-43, 1996). Example 4 This Example describes targeting of the wildtype cystic fibrosis transconductance regulator (CFTR) gene into mammalian cells expressing pIgR using a variation of the methods disclosed in Ferkol et al., J. Clin. Invest., 92:2394-2400 (1993); and Ferkol et al., J. Clin. Invest., 95:493-502 (1995), each of which is incorporated herein by reference. An Fab fragment reactive to the B region of pIgR is made and purified by techniques such as that disclosed in Example 1 (but using a B region peptide rather than the pIgR stalk peptide discussed therein). The Fab is linked to poly (L-lysine) (MW 20,000 Daltons) using the heterobifunctional crosslinking reagent N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP) according to the method of Ferkol et al. (1993). A plasmid comprising the CFTR gene is ligated to a cytomegalovirus early promoter and inserted into the vector pCB6. Thomas et al., J. Biol. Chem., 268:3313-3320 (1993). Complexes of Fab-polylysine-DNA are made by combining plasmid DNA with the Fab-polylysine in 3M NaCl. The complex is introduced by dissolving it in 0.1 ml of phosphate buffered saline, and placing it into the nares of pathogen-free Sprague-Dawley rats (250-300 grams) lightly anesthetized with Metofane inhalant anesthesia. A micropipet will be used to apply 100 μL of the plasmid in PBS directly into the nares of rats that are manually restrained in the supine position. Rats will be held in this position until the solution has been inhaled. This technique has been shown to result in effective application of the sample onto the nasal mucosa. Shahin et al., Infection and Immunity 60:1482-1488 (1992); Gizurarson et al., Vaccine 10:101-106 (1992). Transcription of the transfected gene is assayed by immunofluorescence assay of production of the CFTR protein. Example 5 This Example describes a means of in vivo targeting of exogenous proteins into cells expressing pIgR. An efficient method to allow egress of proteins from endosomes will employ the protein-Fab complex coupled to adenovirus. This method has been used with a number of receptor systems resulting in as much as a 1000-fold increase in expression. Curiel et al., J. Respir. Cell Mol. Biol. 6:247-252 (1992); Curiel et al., Proc. Natl. Acad. Sci. USA 88:8850-8854 (1991), Gao et al., Hum. Gene Ther. 4:17-24 (1993), each of which is incorporated herein by reference. Coupling is accomplished by biotinylation of the adenovirus and the Fab/poly-lysine followed by cross-linking with avidin. The resultant complex is administered as in the preceding Examples. Example 6 This Example describes transcytosis of antibodies which specifically bind to the B region, from the apical to basolateral membrane of a MDCK (Madin Darby canine kidney) cell comprising pIgR. Fab fragments reactive to pIgR are made as described in the preceding Examples. Anti-pIgR B region Fab fragments are radio-iodinated by the iodine monochloride method of Goldstein et al. (Meth. Enzymol. 96:241-249, 1983). Radio-iodinated IgA is used as a control ligand. Radio-iodinated Fab fragments or IgA (107 cpm in 100 μl/well) are added to the apical surface of MDCK and pWe cells grown in a polarized manner for 4 days on 12 mm diameter, 0.4 μm pore size cell culture inserts (Transwells, Costar). Breitfeld et al., Methods in Cell Biology 32:329-337 (1989). Radio-labeled Fab fragments are added to cells with and without a 2 h preincubation with the protease inhibitor, leupeptin, 50 μl/ml. After 20 min of apical uptake at 37° C., unbound radio-labeled ligand is washed with MEM (minimal essential medium)/BSA (bovine serum albumen) three times quickly, one 5 min wash and two more quick washes. The apical and basolateral media are collected and changed at 7, 15, 30, 60 and 120 min time points for quantitation in a gamma counter (Beckman Instruments, Palo Alto, Calif.). Cell culture inserts are cut out at 120 min for quantitation in a gamma counter and to calculate the total initial uptake of radioactivity. The background uptake by MDCK cells are subtracted from that by pWe cells to calculate specific recycling and transcytosis of the radiolabeled ligands. Example 7 This Example sets forth an assay for demonstrating that a ligand binds to the B region of the pIgR, such that the ligand does not bind to a major species of SC present after proteolytic cleavage of the pIgR and does not bind to the stalk of the pIgR. The principle of the assay is immunoblotting (“western blotting”) of pIgR and various fragments of pIgR. The pIgR and its various fragments are first separated by SDS-PAGE, then blotted onto a membrane. The membrane is probed with the test ligand or control antibodies. The membrane is then probed with a secondary antibody which binds to the primary antibody. The membrane is then “developed” with a visualization system, such as the Enhanced Chemiluminescence System, “ECL Plus” kit from Amersham (Amersham Pharmacia Biotech, Piscataway, N.J.)), and the lumninescent light signal is detected by exposing the blot to photographic light. This indicates which fragments of the pIgR do or do not react with the test ligand. A. Expression of pIgR in Madin-Darby Canine Kidney (MDCK) Cells A variety of methods have been used to express cloned cDNAs in MDCK cells, both transiently and in stable cell lines. Conveniently, the retroviral pWE vector may be used, although pDOL vector (Korman et al., Proc Natl Acad Sci USA 84(8):2150-4 (1987) may also be used. In the pWE vector, the gene of interest (cloned into the BamHI site) is driven by an internal chicken beta actin promoter. The neomycin-resistance gene is driven by the viral LTR. BglII linkers are added to the pIgR cDNA. This linked DNA can then be inserted into the BamHI site. Once a suitable construct has been made, plasmid DNA is purified by at least one round of CsCl centrifugation. The psiAM packaging cells can be obtained from Richard Mulligan (Cone and Mulligan, Proc Natl Acad Sci USA 81(20):6349-53 (1984)). Cells are maintained in Dulbecco's minimal essential medium (DME) with 10% calf serum (not fetal bovine serum), 100 units/ml penicillin, and 100 μg/ml streptomycin in 5% CO2. Cells are passaged with trypsin-EDTA every 4-7 days. For transfection, a confluent 10-cm dish is divided 1:10 12-24 hours before use, so that cells are ˜20% confluent when transfected. Plasmid DNA, 10 μg in a volume of 5-20 μl is added to 0.5 ml of sterile HBS in a clear plastic tube. (HBS is prepared by combining 4 g NaCl, 0.185 g KCl, 0.05 g Na2HPO4, 0.5 g dextrose, 2.5 g HEPES in ˜450 ml H20. The pH is adjusted to exactly 7.05 with NaOH. After bringing the volume to 500 ml, the solution is filter-sterilized.) Then, 32 μl of sterile 2 M CaCl2 are added and the tube gently flicked for 20 seconds. The tube is kept at room temperature for 45 minutes to allow a very faint, hazy precipitate to form. The medium is removed from a 10-cm plate of psiAM cells, and the DNA solution is added to the center of the plate. After 10 minutes at room temperature, the plate is gently rocked. After 10 additional minutes, 10 ml of medium are added and the plate placed in the 37° C. CO2 incubator for 4 hours. The medium is removed and 3 ml of a sterile mixture of 85% HBS-15% glycerol are added at room temperature. This is removed after 3.5 minutes and the dish gently washed three times with 10 ml of medium. Finally, 5 ml of medium are added and the dish placed at 37° C. for 18 hours. All necessary biosafety precautions must be observed, and gloves should be worn when handling the virus. After 18 hours the medium, containing transiently produced virus, is removed. Polybrene (Sigma Chemical Co., St. Louis, Mo.) is added to a final concentration of 8 μg/ml. (A polybrene stock of 0.8 mg/ml is prepared in H2O, filter-sterilized, and kept at −20° C.) The virus stock can be frozen at −80° C., although each freeze-thaw cycle decreases the titer somewhat. The titer obtained varies from 10 to 1000 colony-forming units per ml. Titer is determined by infecting the appropriate cells (in this case MDCK), and counting the number of neomycin-resistant colonies that result. There is considerable batch-to-batch variability in the concentration of the neomycin analog, G418, necessary to use with MDCK cells. G418, obtained from Gibco, is dissolved at 100 mg/ml in 0.2 M HEPES-NaOH (pH 7.9), sterile-filtered, and stored at −20° C. G418 shows slow deterioration over several years of storage. It is necessary to determine the optimal concentration of G418 for each batch of drug. MDCK cells are maintained in MEM with 5% fetal bovine serum (FBS), penicillin, and streptomycin, in 5% CO2. (Calf serum can be used, but fetal serum is preferred because it lacks IgA). A confluent 10-cm plate is split 1:10 into several 10-cm dishes. Various amounts of G418 are added to give 0.1-1 mg/ml final concentration. The media and drugs are changed after 7 days. The concentration of drug that kills all cells after 14 days should be used. A 60-cm dish of strain II MDCK cells that is roughly 10% confluent is infected. Then, 1-2 ml of transiently produced virus are added to the dish. After 3 hours, 5 ml of medium are added. In 3 days the cells should be confluent. Cells are trypsinized and taken up in 6.5 ml of medium. To a series of six 10-cm dishes, we add 0.1, 0.2, 0.4, 0.8, 1.6, or 3.2 ml of cells. Medium is added to a final volume of 10 ml, and G418 is added. After 7 days, the media and drug are replaced. After 14 days, medium can be replaced without adding G418. Colonies are visible after 10-14 days, and are picked around day 18-25. Colonies should be picked from a plate containing a few well-separated colonies. Circle the desired colonies with a marker on the bottom outside of the plate. Remove all the medium from the plate. Suck the area around each colony dry with a Pasteur pipet and suction hose, using a separate pipet for each colony. Using sterile forceps, an 8-mm glass cloning ring (Bellco) is dipped in autoclaved Vaseline and then placed firmly over the colony. Then, 75 μl of concentrated tryspin-EDTA (0.5% trypsin 5 mM EDTA) are added. The plate is incubated at 37° C. for 5-10 minutes. Cells are monitored by phase-contrast microscopy. When the cells have rounded up, 75 μl of medium are added to each ring. Using a P-200 Rainin Pipetman® (Rainin Instrument Co., Inc., Emeryville, Calif.) and a sterile yellow tip, the cells are pipeted up and down a few times in the ring. Cells are then transferred. Generally, 80-90% of the cells are put into a 35-mm dish for screening and the balance into a 25-cm2 flask as a reserve. The cells are usually screened by metabolic labeling and immunoprecipitation, which is described below. Usually six clones are selected and screened for a given construct. B. Screening of Clones and Immunoprecipitation For screening clones, 35-mm dishes of cells are labeled. When cells are confluent or nearly confluent, the medium is removed and the monolayer rinsed with PBS. One-half to 0.6 ml of labeling medium containing 2-3 micro of [35S]cysteine (Amersham, ˜700-1100 Ci/mmol, 10-15 mCi/ml) is added. Labeling medium is DME formulated without cysteine and supplemented with 5% FBS (dialyzed against 0.15 M NaCI) and 20 mM HEPES-Na, pH 7.3. The monolayer is labeled for 1-2 hours, and the plates are gently rocked every 15 minutes to keep the cells covered. To harvest the cells, the labeling medium is removed. After this, 0.5 ml of SDS lysis buffer (0.5% SDS, 150 mM NaCl, 5 mM EDTA, 100 units/ml Trasylol® (Bayer Corp., Pittsburgh, Pa.), 20 mM triethanolamine-HCl, pH 8.1) is added, and the cells are scraped off the dish with a small, flat, flexible, rubber spatula. The cell lysate is transferred to a 1.5-ml tube and boiled for 2-5 minutes. After cooling at room temperature for at least 15 minutes, the cells are sonicated. Conveniently, a Branson Sonifier® sonicator (Branson Ultrasonics Corp., Danbury, Conn.) with a cup horn attachment may be used. The tube is sonicated at full power for two 30-second bursts, with intervening cooling period. Then, 0.5 ml of 2.5% Triton dilution buffer (2.5% Triton X-100, 100 mM NaCl, 5 mM EDTA, 100 units/ml Trasylol, 0.1% NaN3, 50 mM triethanolamine-HCl, pH 8.6) is added, along with 30 μl of a 50% slurry of Sepharose CL-2B. The tube is mixed by inverting several times. The tube is centrifuged for 5 minutes in a microfuge, and the supernatant is transferred to a new tube. If any particulate material or “globs” of DNA are observed, a second preadsorption with Sepharose can be performed. Antibody to SC is added to the supernatant. Generally we use 2 μl of a 1:10 dilution of whole serum. Immunoprecipitation is performed by placing the tubes on a gently rotating mixer for at least 90 minutes at room temperature, or overnight at 4° C. Twenty microliters of a 15% slurry of protein A-Sepharose (Pharmacia) are added and the tubes mixed for an additional 30 minutes. Beads are washed by brief (5 seconds) centrifugation, and resuspending in 1.4 ml of wash buffer. The beads are washed are four times with mixed micelle buffer and once with final wash buffer. The protein A-Sepharose beads are sucked dry with a 50 μl Hamilton syringe. Then, SDS-gel sample buffer is added directly to the beads, and the samples are boiled. The samples are analyzed on 10% polyacrylamide SDS gels. The gels are then dried and the distribution of radioactivity determined with a Molecular Dynamics, Inc. Storm® Phosphorimager. The software included with the Molecular Dynamics Phosphorimager is used to calculate the amount of radioactivity associated with each band. C. Preparation of SC-Containing Extract from MDCK Cells Expressing pIgR. MDCK cells expressing pIgR (human, rat, rabbit, etc) can be used. Extracts can be made from cells grown in tissue culture dishes or on permeable supports, such as Corning Costar Transwell membranes. For SC harvest, 1 ml of the apical media is collected into a 1.5 ml tube and SDS is added to 0.5%. The sample is boiled for 5 minutes, followed by addition of 0.5 ml of 5% triton dilution buffer (5% Triton X-100, 100 mM NaCl, 5 mM EDTA, 100 units/ml Trasylol, 0.1% NaN3, 50 mM triethanolamine-HCl, pH 8.6). Then 50 μl of a 50% slurry of Sepharose CL-2B is added, the tube is shaken, and centrifuged at 12,000×g. Antibody to SC is added to the supernatant. Generally, 2 μl of a 1:10 dilution of whole serum is used. Immunoprecipitation is performed by placing the tubes on a gently rotating mixer for at least 90 minutes at room temperature, or overnight at 4° C. Twenty microliters of a 15% slurry of protein A-Sepharose (Pharmacia) are added and the tubes mixed for an additional 30 minutes. Beads are washed by brief (5 seconds) centrifugation, and resuspended in 1.4 ml of wash buffer. Four washes are performed with mixed micelle buffer (20 mM Triethanolamine pH 8.6, 150 mM NaCl, 5 mM EDTA, 5% sucrose, 1% Triton X-100, 0.02% SDS, 10 Units/ml aprotinin, 0.02% sodium azide) and one with final wash buffer (20 mM Triethanolamine pH 8.6, 150 mM NaCl, 5 mM EDTA, 5% sucrose, 10 Units/ml aprotinin, 0.02% sodium azide). The protein A-Sepharose beads are sucked dry with a 50 μl Hamilton syringe. Then, SDS-gel sample buffer is added directly to the beads, and the samples are boiled and subjected to western blot analysis as described below. D. Preparation of SC-Containing Extract from the Lumen of Cynomologous Monkey Intestine Rinse the lumen of freshly harvested monkey intestine (10 cm segment) into a dish or other container with 3 ml PBS. To the lumenal contents rinsed into the dish or other container, add the following protease inhibitors: 5 μg/ml pepstatin, 10 μg/ml chymostatin, 5 μg/ml leupeptin, 10 μg/ml antipain, 500 μM benzamidine, 0.01 U/ml aprotinin (trasylol, Bayer), and 1 mM PMSF. Add EDTA to a final concentration of 1 mM. Add SDS to a final concentration of 2%. Boil the sample for 5 minutes. Centrifuge at 12,000 g (full speed in a table top microcentrifuge) for 10 minutes at room temperature. Transfer the supernatant to a new tube. Vortex shake the sample for 5 minutes. Add 1/10 volume of a 50% slurry of CL-2B. Mix by inverting 5 times, then centrifuge at 12,000 g for 5 minutes at room temp. Transfer the supernatant to a new tube. Repeat the procedure in this paragraph once. Optionally, the supernatant can be subjected to immunoprecipitation with an appropriate antibody to concentrate the sample. To the sample add an equal volume of 2× Laemmli SDS gel sample buffer containing 100 mM DTT. Boil 3 minutes and load 10 μL on a 10% polyacrylamide gel (Laemmli). Electrophorese until the bromophenol blue is ˜1 cm from the bottom. E. Production of Antibody Against Secretory Component Secretory component (SC) is a large proteolytic fragment of the pIgR and is easily purified from rabbit bile, rat bile, or bile from other species of interest. Rabbit bile can be purchased from Pel Freez Biologicals, Rogers, Ariz. Rat bile can be obtained by canulation of the bile duct of anesthetized rats. Phenylmethylsulfonyl fluoride (PMSF) is added to 1 mM, and the bile is dialyzed against three 12-hour changes of 100 volumes 0.15 M NaCl. About 1 ml of bile is loaded onto each of six preparative sodium dodecyl sulfate (SDS)-7% polyacrylamide gels (20×20×0.15 cm) using the Laemlli system. No reducing agent is used. As a molecular-weight standard, 1 microliter of whole serum can be run in a side lane. The gel is stained with Coomassie blue. The smeary complex of bands running slightly slower than serum albumin is SC and is excised. The gel slices are lyophilized and ground with a mortar and pestle. We have found that guinea pigs produce excellent antibodies against this preparation of SC, and the antibodies bind well to protein A. The animals are injected with 50 mg of ground gel every 3 weeks for six injections, using Ribi adjuvant (Ribi Immunochem Research, Inc., Hamilton, Mont.). Animals are bled 7-10 days after each of the last three injections. Whole serum can be used for immunoprecipitation F. Modified Rapid Western Blot Procedure: Transfer the gels from steps C and D, above, to PVDF according to Millipore instructions for 1 hour (Millipore Corp., Bedford, Mass.). Transfer buffer: 25 mM Tris, 192 mM glycine, 10% (v/v) methanol. After transfer, dip the blot in methanol for 10 sec. then air dry for 20 minutes. Incubate blot for 1 hour with primary (Test) antibody in Ab dilution buffer (PBS containing 0.05% Tween 20 and 1% non-fat milk). Wash 3 times 10-60 seconds each with PBS. Incubate 30 minutes with appropriate secondary antibody in Ab dilution buffer at 1/10,000- 1/20,000 or empirically determined dilution. Wash as before. Develop with chemiluminescent substrate (Enhanced Chemiluminescence, “ECL”, kit from Amersham (Amersham Pharmacia Biotech, Piscataway, N.J.)) and expose to appropriate film. As a reference, all forms of pIgR SC can be visualized with a polyclonal anti-SC antibody. Sheep anti-SC antibody works for most primate species, including human. G. Interpretation: Duplicate gels should be run, with the following samples run side by side on each of the gels to facilitate comparison: 1. Intact pIgR from pIgR-expressing MDCK cells. 2. SC from apical medium of pIgR-expressing MDCK cells. 3. SC from monkey intestinal lumen. The gels should then be blotted in a western blot as described above, with incubation and development steps as described in the previous section. One gel is probed with a sheep anti-SC antibody which will react with all forms of pIgR and SC in all three samples. The other duplicate gel is probed with the test ligand to the B region. A ligand binding to the B region but not to the stalk and not to the major species of the SC present in a mammalian intestine will react with intact pIgR and with SC from the apical medium of pIgR expressing MDCK cells. This ligand will not react with the major form of SC present in the monkey intestinal lumen. Example 8 This Example sets forth an exemplary assay for determining whether a ligand inhibits the cleavage of pIgR. The principle of this assay is to metabolically pulse label the pIgR with radioactive amino acids. In a pulse-chase experiment, the cleavage of the pIgR to SC and its release into the apical medium overlying a MDCK cell monolayer is then followed. The rate of cleavage to SC and release is compared in the presence or absence of a ligand that may inhibit cleavage; if the rate of cleavage is decreased in the presence of the ligand, it is deemed to inhibit cleavage. A. Production of Antibody Against Secretory Component Antibody binding to SC is produced following the procedure set forth in part C of the preceding Example. B. Expression of pIgR in Madin-Darby Canine Kidney (MDCK) Cells Expression of pIgR in MDCK cells is performed as in the previous Example. C. Screening of Clones and Immunoprecipitation Screening of clones and immunoprecipitation are performed as described in section B of the preceding Example. D. Growing MDCK Cells on Filters. Growth of MDCK cells on filters leads to increased cell polarity and allows separate access to the apical and basolateral surfaces. In preferred embodiments, the filters are 12 mm diameter, 0.4 micron pore size polycarbonate Transwell filters from Coming (Transwell permeable supports, Coming Inc., Miami Fla.). Cells are maintained on 10-cm tissue culture plates in medium containing 5% FBS. However, 10% serum is used when the cells are actually on the filters. To plate cells on filters, a Transwell filter is placed in a 12-well tissue culture tray. Sufficient medium (containing 10% serum) is added to both the inside and outside of the Transwell filter to wet the filter. Cells from a confluent 10-cm dish are trypsinized, gently pelleted by centrifugation, and resuspended in 10 ml of medium containing 10% serum. 0.4 ml of cells are pipeted into the Transwell. Transwells are then placed in the 37° C. incubator, and are generally used after 3 or 4 days. The medium is changed after 1 or 2 days. E. Pulse-Chase Analysis of Cells on Filters. Confluent MDCK cell monolayers on polycarbonate filters are washed twice with PBS and starved in MEM minus cysteine for 15 min at 37° C. Proteins are then pulse-labeled by placing the Transwell on a 25 μl drop of MEM minus cysteine containing 44 μCi of [35S] cysteine (specific activity: 1000 Ci/mmole) for 10 min at 37° C. For the chase, cells are then rinsed with MEM and by adding 0.2 ml MEM to the apical surface and 1 ml to the basolateral surface. Cells are then chased for various times, generally 0.5 h, 1 h, 2 h, 3 h, and 4 h. During the chase period, the test ligand directed against the pIgR that may or may not inhibit cleavage of the pIgR is included in the apical medium. In different samples, the test ligand is included at different concentrations, such as 10 μg/ml, 100 μg/ml, 1 mg/ml, and 5 mg/ml. In a negative control experiment, the test ligand is omitted, or a control ligand that is known not to inhibit cleavage of the pIgR is included in the apical medium. In a positive control experiment, leupeptin is included in the medium at a concentration of 0.1 mg/ml during the chase period. At the conclusion of each chase period (i.e. 0, 0.5, 1, 2, 3 or 4 h), the apical medium is collected. To harvest the cells on filters, the filter is cut out from the holder with a scalpel. The filter is placed in a 1.5-ml tube containing 0.5 ml of SDS lysis buffer and boiled for 5 minutes. The liquid is then transferred to a new tube and immunoprecipitated as described earlier. To immunoprecipitate the medium, SDS is added to the medium to a final concentration of 0.8%, and the medium is boiled for 2 minutes. An equal volume of 5% Triton dilution buffer (same as 2.5% Triton dilution buffer, except with 5% Triton X-100) is added and the sample processed for immunoprecipitation in the same manner as the cell extract described above. The immunoprecipitates are analyzed by SDS-PAGE and the radioactivity in the different species quantitated using the Molecular Dynamics Phosphorimager. F. Interpreting the Results of Pulse-Chase Experiments. Immediately after the pulse period, the pIgR immunoprecipitated from the cells will have a Mr of approximately 105,000. After a chase of 0.5 or 1 h, the pIgR immunoprecipitated from the cells will have a Mr of approximately 120,000 due to modification of its oligosaccharide side chains to the complex type. Beginning at about 1 h and continuing thereafter, the pIgR will be cleaved to SC with an Mr of approximately 80,000 and released into the apical medium, where it will be immunoprecipitated. The rate of disappearance of the intact 120,000 Mr pIgR from the cells and the appearance of the 80,000 Mr SC in the apical medium is indicative of the rate of cleavage of pIgR to SC. The presence of a ligand that inhibits cleavage of pIgR to SC in the apical medium during the chase period will inhibit this process and will be reflected in a lower rate of appearance of the 80,000 Mr SC. Example 9 This Example sets forth an exemplary protocol for in vivo testing of ligand binding. As discussed in more detail below, rats are anesthetized, the contents of the colon flushed, and radiolabeled ligand perfused through the colon. Ligand binding, transcytosis, delivery into the circulation and delivery into the organs is then monitored by measuring radioactivity in blood samples and in organs. A. Animals The experiments are performed on male Sprague Dawley Rats(Sasco), weighing 250-380 g. The rats are fasted overnight before each experiment. Anesthesia is induced by an i.m. injection of ketamine (70 mg/kg) and acepromazine(30 mg/kg). B. Animal Surgery The perfused segment is colon. The surgical procedure is similar to that described in earlier publications (Hu, et al., J Theor. Biol., 131:107-114 (1988); Zheng et al., Pharm. Res., 11: 1771-1776 (1994)), with minor modifications. In this study, the cannulation to the colon is through an inter-cannulae, which is 1.5-2 cm long and can be easily disconnected or reconnected. The bile duct is also cannulated for collecting the bile (see, Borchardt, R. T., et al., eds. Models for Assessing Drug Absorption and Metabolism (Plenum Press, New York, N.Y. 1996)). Briefly, after the cannulation of the colon, the bile duct is located and cannulated using PE10 tubing. The cannulae is secured with surgical silk suture. The incision is then covered with a paper towel wetted with normal saline. A piece of plastic wrap is put on the towel to keep the segment moist. To keep the temperature of the perfusate constant, the inlet cannulate is insulated and kept warm by a 37° C. circulating bath. C. Perfusion The colon is perfused in situ with a washing buffer (a modified Hank's Balanced Salt Solution with leupeptin (0.1 mg/ml), aprotinin (50 U/ml), BSA(1 mg/ml), chymostatin (0.05 mg/ml)and NaI 0.1 mM, with/without NAC (20 mM)) to clean up the content. A washing buffer is then introduced into the colon under mild pressure to ensure distention for 2 min, and then removed. This washing is repeated 3 times. The perfusate solution (washing buffer without NAC but with the ligand and with PEG-4000 (100 μM)) is then introduced at a flow rate of 0.192 ml/min for the first 15 min, and at a flow rate of 0.077 ml/min for additional 15 min. D. Sampling Samples of the perfusate are collected for two hours at 30 min intervals at a flow rate of 0.077 ml/min. The perfusion is then stopped, and the colon is closed and kept closed for the remainder of the study. After 8 hr of perfusion, the perfusate is pushed out of colon using a syringe and collected. The perfused segment is then collected and its length measured by wetting it with normal saline and carefully laying it flat without stretching. The outlet concentration of the test compound is determined by a Gamma counter. In addition to perfusate sampling, the blood samples(0.15-0.20 ml) are taken at 15, 30, 60, 90, 120 150, 240, 330, 420 and 480 min after the start of the perfusion. The bile is collected from the cannulae of the bile duct from time zero to the end of the studies. The weights of the blood and the bile are recorded by weighing the tubes with heparin (for the blood) or without (for the bile) before and after sample collection. Rats are euthanized and organs harvested at the end the study. Weights of heart, lung, liver, spleen, kidney, intestine, colon and cecum are measured. The amount of the test compound in each organ is determined by using the gamma counter. The appearance of the radiolabel in the organs is a measure of the binding, internalization, transcytosis, and release, of the ligand. The stability of the perfused 125I-labeled proteins is checked by precipitation of the collected blood, bile and perfusate samples. Briefly, 100 μL (2 M) trichloracetic acid (“TCA”) is added to 200 μL each of the samples. The mixture is centrifuged at 16,000 G, for 5 min at room temperature. The pellet is collected by discarding the supernatant. The efficiency of the precipitation is calculated from the measured CPM values before and after the precipitation. Example 10 This Example describes the creation of an antibody bearing a “FLAG”®. FIG. 5 sets forth the sequence of an exemplary antibody, antibody 4AF, bearing a FLAG® tag. Antibodies for detecting the FLAG® tag are commercially available from Sigma (St. Louis, Mo.). For convenience in secreting the antibody, scFv are typically engineered to have a so-called “pelB” leader sequence, which improves periplasmic secretion when the antibody is produced in E. coli. The leader sequence is cleaved upon secretion by the bacteria. The sequence further contains, immediately following the carboxy-terminus of the scFv, a Not I restriction site and a “myc” tag (an epitope from the myc oncogne) which can be specifically bound by commercially available antibodies. Finally, the sequence includes at the carboxy end six histidines. This “6HIS” tag permits ready purification of the secreted protein by running the protein over a column packed with nickel immobilized on a resin, as the histidines chelate to the metal. The preferred immobilized metal affinity chromatography, or “IMAC,” process used to purify the scFv is nickel-NTA-superflow. The “FLAG®” tagged version of the scFv is made by amplifying the scFv DNA in the plasmid pSyn (a pUC119 derivative which contains the pelb leader sequence which improves secretion in E. coli), using a primer which hybridizes in the vector sequence 3′ to the ScFv coding region. A second primer is used which adds a FLAG® tag to the N-terminus of the ScFv. This primer is designed to contain a Nco I restriction site. The primer hybridizes to the 5′ end of the ScFv coding region in the conserved framework region. The resulting PCR product is cloned back into pSyn using the restriction enzymes Nco I and Not I. Myc is a second tag, which is identified by a mouse monoclonal antibody, 9E10, available from the American Type Culture Collection (Manassas, Va.). Example 11 This Example sets forth an exemplary protocol for in vitro testing of binding, transcytosis, and release of anti-pIgR-antibodies. The scFv or other antibody to be tested is radio-iodinated by the method of Goldstein et al., (Meth Enzymol. 96:241-249, 1983), except that the iodine monochloride is diluted an additional 5-fold before addition to the reaction mixture. For each scFv to be tested, three 12 mm 0.4 um pore size Transwell filters (Costar) containing MDCK cells transfected with the appropriate species of pIgR (that is, human, rat, etc.) and three filters containing non transfected MDCK cells as a control, are cultured for 4 days, as described in Breitfeld et al., (1989), supra. The iodinated scFvs (10 cpm in 300 ul of minimum essential medium (“MEM”)/bovine serum albumin (“BSA”) are added to the apical chamber of each Transwell, and 800 μl of MEM/BSA is added to the basal medium. The filter units are transferred to new cluster dishes containing fresh basal medium at the desired time points (typically 1, 2, 4, 8, and 12 hours). At the end of the assay, apical medium is collected, and the filters are washed four times with cold MEM/BSA. If the scFv is engineered to contain a tail containing six or more histidines, the intact scFv cam can be precipitated from the apical and basal media using immobilized nickel resin (Qiagen). If the scFv are not engineered to contain a repetitive histidine sequence, the scFv can be precipitated with an antibody to another tag on the ScFv, or by TCA precipitation. After washing with PBS to remove non-specific radioactivity, the basal media, apical media, and filters can be quantitated in a gamma counter (Beckman Instruments, Palo Alto, Calif.). The percentage of the total ligand added that is transcytosed can be determined, and specific transcytosis can be assessed by comparing the pIgR expressing cells with the non-transfected MDCK cells. Example 12 This Example describes the epitopes to which various human scFvs displayed in filamentous phage bound. A series of 87 “staggered” peptides of 15 amino acid residues each were created from the pIgR sequences of the human, rat and mouse pIgR sequences, respectively. Each peptide within a series (that is, from the peptide sequence of a particular species) overlapped by 12 amino acids the next peptide in that series. Additionally, peptides created from the sequence of rabbit pIgR were created. Peptide binding was tested by ELISA, following a protocol developed by Chiron Technologies (since acquired by Mimitopes Pty. LTD., Melbourne, Australia), as set forth in the Example below. The studies revealed that antibody 4A bound to the epitope defined by the sequence QDPRLF in human pIgR (residues 600 to 605 of the human sequence as set forth in SWISS-PROT) and to the epitope defined by the sequence LDPRLF (SEQ ID NO:11) in rat pIgR (residues 605-610 of the rat pIgR sequence), an epitope also bound by antibody 5D. Antibody 5D also bound to the epitope defined by the sequence KAIQDPRLF (SEQ ID NO:12) of human pIgR. ScFv 2E bound to the epitope defined by the sequence LDPRLFADERI (SEQ ID NO:13) of rat pIgR. ScFv 2H bound to the epitope defined by the sequence DENKANLDPRLF (SEQ ID NO:14). ScFv IF bound to the epitope defined by the sequence RLFADERI (SEQ ID NO:15). ScFvs 5F, 10H, 1C, 7H, and 6B all bound to the epitope defined by the sequence LDPRLFADE (SEQ ID NO:16). Example 13 This Example describes determining assaying for binding of scFv or other antibodies to peptides derived from pIgR. The binding of scFv antibodies from a human library was mapped by creating 94 peptides derived from pIgR of human, mouse, rat, and rabbit. The peptides were tested pursuant to the following protocol: Introduction The use of peptides in solid-phase immunoassays requires an efficient method for immobilization of the peptides on the solid phase, i.e. a method which does not depend on the amino acid sequence of the peptide being tested (Geerligs, H. J. et al., J. Immunol. Meth. 106:239-244 (1988)). For this purpose, multiple synthetic peptides are biotinylated and attached to a plastic surface coated with avidin or streptavidin (Weiner, A. J. et al., Proc. Natl. Acad. Sci. USA 3468-3472 (1992)). Materials Required Biotinylated synthetic peptides; microtiter plates e.g. Nunc Immuno-Plate MaxiSorb F96 (Cat. No. 4-42404); streptavidin (Sigma Cat. No. S-4762); bovine serum albumin (BSA); sodium azide PBS/Tween 20 (0.1% Tween 20 in PBS); PBS/BSA/azide (0.1% BSA and 0.1% sodium azide in PBS); 2% BSA/PBS (PBS containing 2% BSA) conjugate substrate; and an ELISA plate reader. Method 1. Coat Nunc Immuno-Plate MaxiSorb F96 flat bottomed plates (Cat. No. 4-42404) with 5 microgram/mL streptavidin (Sigma Cat. No. S-4762) diluted in purified water. Add 100 microlitres of the streptavidin solution to each well and leave plates exposed to the air at 37 degrees C. overnight to allow the solution to evaporate to dryness. 2. Wash plates with Phosphate Buffered Saline (“PBS,” 0.01M sodium phosphate in 0.15M sodium chloride, pH7.2) containing 0.1% (v/v) Tween 20 (PBS/Tween 20). The washing technique is as follows: flood the plate, filling all the wells with solution, then vigorously flick the solution from the wells. This washing step is repeated 4 times. After the washings, excess buffer is removed from the wells by vigorously “slapping” the plates, wells down, on a benchtop covered with an absorbent material (paper towels). 3. To block non-specific absorption, add to each well 200 uL of a solution consisting of PBS containing 2% (w/v) bovine serum albumin (2% BSA/PBS) and incubate the plate at 20 degrees C. for 1 hr. 4. Repeat washes as described in Step 2. 5. The biotinylated peptides are supplied as a dry powder in Bio-Rad polypropylene tubes (Cat. No. 223-9390). The identity of the peptide in each tube is given in the information supplied with the peptides. For use, we recommend that the peptides are reconstituted in 200 microlitre of either a pure solvent (e.g. dimethyl sulfoxide or dimethyl formamide) or solvent/water mixture. Each peptide should be diluted just before use to a working strength of 1/1000 in PBS/BSA/azide, i.e. PBS containing 0.1% BSA and 0.1% sodium azide. The peptide stock solution may be diluted further (down to 1/5000), however some loss in ELISA sensitivity may occur if used too dilute. 6. An initial 1/100 dilution is conveniently made using 1 mL capacity polypropylene tubes, held in an 8×12 format rack (Bio-Rad Cat. No. 223-9390 as used for supply of the peptides is suitable). Using a multichannel pipette, transfer a 10 uL aliquot of peptide solution into each tube, then add 1 mL of the PBS/BSA/azide, cap the tubes and invert several times to ensure thorough mixing. The diluted peptide solutions may be stored for several days at 4 degrees C. For longer storage the diluted peptide solutions should be stored frozen. The tubes containing the supplied peptides should be resealed and stored frozen immediately after sampling, at −70 degrees C. To react the streptavidin coated, BSA blocked plates with the biotinylated peptides, transfer 100 microlitre of each of the diluted peptide solutions into the corresponding well positions of the plate, place the plate shaker and allow the reaction to proceed for 1 hr at 20 degrees C. For convenience, several sets of immobilised peptides may be prepared simultaneously. 7. Repeat washes as described in Step 2. The plates should be dried at 37 degrees C. before storage at 4 degrees C. in the dry state if they are not to be used immediately. 8. Dilute the serum to be tested, using as diluent 2% BSA/PBS containing 0.1% sodium azide. The dilution of the serum will depend to some extent on the source and the level of antibodies present in sample. The recommended dilutions are 1/1000 for hyperimmune serum from experimental animals and ascites fluid from hybridoma-bearing mice, and 1/500 for human serum. For scFvs, a concentration of between about 10 and 100 μg/mL is desirable. Conveniently, an scFv with an epitope tag to faciliater later detection. Add 100 microliters of the scFv or diluted serum to each of the wells of the plate containing captured peptides. Place the plate on a shaker and incubate for 1 hr at 20 degrees C. or overnight at 4 degrees C. Better sensitivity has been observed for some antibodies with overnight reaction. 9. Repeat washes as described in Step 2. 10. Bound antibody is detected after reaction for 1 hr at 20 degrees C. with 100 microlitre conjugate comprising a saturating level of horse radish peroxidase-labelled anti-species antibody (for the diluted serum samples; use 1/2000 dilution of the 0.5 mg pack size conjugate from Kirkegaard and Perry Labs, Maryland, to be made up in 2% BSA/PBS. Note: do not use a diluent containing azide for HRP conjugates. For an epitope-tagged scFv, use an antibody appropriate for the epitope tag employed.) 11. Repeat washes as described in Step 2. 12. Wash the plate twice with PBS only (no Tween): to remove traces of Tween remaining from the washing buffer. 13. The presence of enzyme is detected by reaction for up to 45 min at 20 degrees C. with 100 microlitre/well freshly prepared enzyme substrate solution. The substrate solution consists of 50 mg of (2,2′-Azino-di-[3-ethylbenzothiazoline sulphonate]; Boehringer Mannheim Cat. No. 122661) and 30microlitre of 35% (w/w) hydrogen peroxide solution in 100 mL of 0.1 M phosphate/0.08M citrate buffer, pH4.0. Using substrate the absorbance of the converted substrate solutions (product) in each well is read using a plate reader. The Titertek Multiskan MC plate reader in the dual wavelength mode at 405 nm against a wavelength of 492 nm is suitable. The absorbance values are recorded and stored on a diskette for later analysis. The plate-reading software suppied with peptide synthesis kits is suitable for this purpose. Notes Other brands of streptavidin, or avidin, may be used to coat plates; however, to obtain optimum results, coating conditions may need to be varied. Avidin is cheaper than streptavidin but avidin-coated plates tend to result in higher background absorbance readings. Other ELISA enzyme/substrate systems may be used, but the sensitivity of the test will vary accordingly. conditions for each ELISA system should be optimised (substrate concentration, pH, temperature, time etc.). A test should be done using preimmune, negative or normal serum to verify that any binding observed was to specific antibodies. Likewise, a negative control test can be performed with direct addition of conjugate toplates coated with (strept)avidin-peptide to ensure that the positives are not due to conjugate binding directly the peptide. Example 14 This Examples sets forth an exemplary protocol for the production of fusion proteins comprising the pIgR B region and the stalk, and for producing polyclonal antibodies directed against the B-region and the stalk. A. Production of Glutathione-S-Transferase Fused to Rat pIgR Residues 547-643 (GST-ratpIgR547-643). cDNA encoding rat pIgR was amplified by PCR to incorporate BamI and EcoRI sites. The resulting PCR product was cleaved with BamHI and EcoRI, and cloned into BamHI/EcoRI cleaved pGEX2tk (Pharmacia). The pGEX2tk had been previously modified so that it encodes an in-frame 6HIS tag downstream of the cloning sites. The ligation mixture was used to transform E. coli DH5alpha. Positive clones were screened for expression of fusion protein after induction of cultures with IPTG. Clones that expressed well were used to make large scale (1 Liter) cultures expressing fusion protein. The bacteria were pelleted, resuspended in 1/100th the original culture volume (10 ml) PBS containing 0.2 mM PMSF. Tubes containing 5-10 ml of the cell suspension were sonicated using a Branson Model 250 sonifier (8 15 sec burst at setting 7). Trion X-100 was added to a final concentration of 1%, and the sample was rotated at 4 degrees for 10 minutes. Fusion protein was then purified using Glutathione Sepharose according to the Pharmacia protocol. Yields from DH5alpha were typically 2 mg fusion protein per liter of bacterial culture. The pGEX2tk vector with the 6HIS tag was also transformed into E. coli strain DH5alpha, and protein was prepared as described above. B. Antibody Production Fusion proteins were sent to to HTI Bioproducts (now called Strategic Biosolutions, Ramona, Calif.) for antibody production in goats, rabbits and chickens. For goats, 200 ug of fusion protein was used for the initial injection (Day 1) with Complete Freund's Adjuvant. Booster injections of 200 ug fusion protein with Incomplete Freund's Adjuvant were given on days 14, 28, and 42. All injections were subcutaneous. A test bleed was done on day 49, and the blood was screened by ELISA for reactivity with the fusion protein. Positive bleeds were tested by western blot to confirm reactivity with pIgR. Animals with high titers were subjected to plasmaphoresis. Goat IgG was purified from plasma ion-exchange chromatography. IgG was further purified by affinity purification on GST-ratpIgR547-643 coupled to Affi-Gel (Bio-Rad) according to the protocol supplied with Affi-Gel. Antibodies reactive with the GST portion of the molecule were removed by incubating the antibody preparation with GST protein coupled to Affi-Gel. Epitope mapping of the antibodies was performed as described above with respect to testing of scFvs, using non-affinity purified IgG. It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. All publications and patents mentioned in this specification are herein incorporated by reference into the specification to the same extent as if each individual publication or patent was specifically and individually indicated to be incorporated herein by reference. | <SOH> BACKGROUND OF THE INVENTION <EOH>One of the most challenging problems facing the pharmaceutical and biopharmaceutical industries is delivering therapeutic agents past the various semi-permeable membranes within the body. Particularly in the case of macromolecules, the obstacle to cost effective or convenient treatment is often due to the lack of an adequate drug delivery system. In turn, this issue dictates whether production of a drug is economically feasible. Thus, the search for alternative delivery systems often rivals the search for new drugs themselves. Gene transfer methods can be viewed as a paradigm of macromolecular drug delivery. These methods can be divided into three categories: physical (e.g., electroporation, direct gene transfer, and particle bombardment), chemical (e.g., proteinoids, microemulsions, and liposomes), and biological (e.g., virus-derived vectors, and receptor-mediated uptake). Among biological transfer methods, receptor-mediated uptake is a particularly promising approach. Targeting a ligand to an endocytosed receptor acts as a means to ferry that ligand into the cell. One drawback of receptor-mediated systems, however, has been their general reliance on intravenous administration, which severely limits their use. Mucosal epithelial cells line a number of readily accessible tissues such as those found in the upper respiratory and gastrointestinal tracts. The accessibility of these cells make them an attractive target for drug delivery. See, e.g., Ferkol et al., J. Clin. Invest. 92:2394-2400 (1993); Ferkol et al., J. Clin. Invest. 95:493-502 (1995). Retrograde transport of an antibody from the lumenal to the basolateral surface of epithelial cells has been reported, albeit at very low levels. Breitfeld et al., J. Cell Biol. 109:475-486 (1989). In that study, movement across the cell was followed by binding an antibody to the secretory component of polymeric immunoglobulin receptor (“pIgR”). Relative to the level of basolateral to apical transport, Breitfeld et al. reported that less than 5% of the transport was retrograde in nature. The nominal level of counter-transport minimizes the utility of secretory component as a means to deliver biologically active compositions into cells. Moreover, due to the abundance of cleaved pIgR in the lumen, binding of ligand to cleaved pIgR, rather than the intact pIgR of the cell surface, would diminish the utility of pIgR counter-transport as a mechanism of drug delivery. In commonly-assigned application Ser. No. 08/856,383, now U.S. Pat. No. 6,042,833, it was reported that a stalk remained on the surface of the cell following cleavage of the secretory component (“SC”). It was further found that ligands could be targeted to the stalk and thereafter undergo internalization and retrograde transport. As useful as this is, the stalk represents a limited target for ligands and it would be helpful to have additional targets for ligands which can be internalized and which are not diluted by binding in substantial amounts to cleaved pIgR. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>This invention provides ligands that bind specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell of an animal, which pIgR when cleaved has a stalk region which remains attached to the cell and a secretory component (SC) which exists in an organ of interest in several forms, provided that the ligands do not substantially bind to the most abundant form of SC present in the organ of interest and provided further that the ligands do not substantially bind to the stalk of said pIgR under physiological conditions. The ligands can bind to the pIgR of birds or of mammals. With regard to mammals, the ligands can bind to the pIgR of a mammal selected from the group consisting of pig, cow, horse, sheep, goat, cat, dog, and human. The ligands can be, for example, an antibody, a humanized antibody, a recombinant single chain variable region fragment of an antibody or a disulfide stabilized variable region fragment. In some preferred embodiments, the ligands bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some particularly preferred embodiments, the ligands bind to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The organ of interest may be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a salivary gland, a stomach, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The ligands may comprise a binding component for binding to pIgR and a biologically active component. In one set of embodiments, the biologically active component is a nucleic acid encoding the wildtype cystic fibrosis transmembrane conductance regulator. In other sets of embodiments, the biologically active component is selected from the group consisting of a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. In one set of embodiments, the invention provides ligands that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell of an animal, which pIgR has an initial cleavage site and which upon initial cleavage has a stalk region which remains attached to the cell and a secretory component (SC) which exists in an organ of interest in several forms, provided that the ligand does not substantially bind to the most abundant form of SC present in the organ of interest and provided further that the ligand does not substantially bind to a peptide comprising 31 amino acids that are cell-membrane-proximal to the initial cleavage site. In another group of embodiments, the invention provides a method of introducing a ligand into a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor, by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. In some of these embodiments, the ligand is an antibody, and may be a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region fragment, either of which may be humanized. The ligand can selectively bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some preferred embodiments, the ligand binds to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The method further encompasses embodiments wherein the ligand is further defined as having a binding component for selectively binding to pIgR and a biologically active component. The biologically active component may be a nucleic acid which encodes the wildtype cystic fibrosis transmembrane conductance regulator. In other embodiments, the biologically active component may be selected the group consisting of a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. The cell may be a mammalian cell, especially an epithelial cell. The organ of interest may be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. In another group of embodiments, the invention provides a method of introducing a ligand into a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), which pIgR has an initial cleavage site which, upon initial cleavage has a stalk region, the method comprising binding the ligand to a region of the pIgR, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions; (b) the ligand does not substantially bind to a stalk region of the pIgR; and (c) the ligand does not bind to an extracellular epitope within the first 31 amino acids that are cell membrane proximal to the initial cleavage site of the pIgR, thereby permitting introduction of the ligand into the cell. Yet another method provided by the invention is a method of increasing the rate by which a first ligand which binds to secretory component (SC) is internalized into a cell secreting a polymeric immunoglobulin receptor (pIgR) from an apical surface by (a) binding the pIgR with a second ligand, which second ligand inhibits proteolytic cleavage of SC by at least one-third, and further which second ligand does not substantially bind to a stalk remaining attached to the cell after proteolytic cleavage, and (b) binding the first ligand to the SC, thereby permitting internalization into said cell of the SC to which the first ligand is bound. The invention further provides ligands that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell, provided that binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of binding of the ligand and provided further that the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions. The ligand may be an antibody, a scFv, a recombinant single chain variable region fragment of an antibody, a disulfide stabilized variable region fragment (“dsFv”), a humanized scFv, or a humanized dsFv. The ligands may bind to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In one set of embodiments, the ligand binds to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The ligand may further be a binding component of a molecule comprising a biologically active component. In some embodiments, the biologically active component may be selected from the group consisting of: a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In yet another embodiment, the biologically active component is a small molecule. In yet another, the biologically active component is a nucleic acid encoding the wildtype cystic fibrosis transmembrane conductance regulator. In yet another set of embodiments. the invention provides a conjugate, fusion protein, or complex, said conjugate fusion protein or complex comprising a ligand that binds specifically to a region of a polymeric immunoglobulin receptor (pIgR) of a cell and a biologically active component, provided that binding of the conjugate, fusion protein, or complex to pIgR reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of binding of the conjugate, fusion protein, or complex and provided further that the conjugate, fusion protein, or complex does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions. In another set of embodiments, the invention provides methods of introducing a ligand into a cell expressing a polymeric immunoglobulin receptor (pIgR) by attaching the ligand to a region of the pIgR, provided that (a) binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby permitting introduction of the ligand into the cell. The ligand may be, for example, an antibody, a humanized antibody, a scFv, a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region. The ligand preferably binds to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some embodiments, the ligand binds to an epitope of pIgR selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). The ligand may have a binding component for selectively binding to a region of pIgR and a biologically active component. The biologically active component may be selected from the group consisting of: a nucleic acid, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antibiotic, and an anti-infective. In one set of embodiments, the biologically active component is a small molecule. The animal can be a mammal. In one embodiment, the biologically active component is a nucleic acid encodes the wildtype cystic fibrosis transmembrane conductance regulator. The cell can be a mammalian cell, especially an epithelial cell. The ligand can bind to the pIgR at the apical surface of the cell. The ligand can then be transcytosed to the basolateral side of the cell, and may remain attached or can be released from the pIgR at the basolateral surface of the cell. The SC can exist in several forms in an organ of interest, provided that the ligand (a) does not bind to the most abundant form of SC present in the organ of interest, and (b) does not bind to a stalk remaining on an extracellular surface of a cell of the organ of interest after pIgR cleavage. The organ of interest can be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The invention further relates to methods of attaching a ligand to a cell expressing a polymeric immunoglobulin receptor comprising the step of binding the ligand to the receptor with the provisos that (a) the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby attaching the ligand to the cell. The method can permit the ligand to be internalized into the cell after binding. The invention also provides a method of attaching a conjugate, fusion protein, or complex to a cell expressing a polymeric immunoglobulin receptor, said conjugate, fusion protein, or complex comprising a ligand that binds to a region of pIgR and a biologically active component, said method comprising the step of binding the ligand to the receptor with the provisos that (a) the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby attaching the conjugate, fusion protein, or complex to the cell. The invention further provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by binding the ligand to a region of the polymeric immunoglobulin receptor, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions and (b) the ligand does not substantially bind to a stalk region of the pIgR, thereby permitting introduction of the ligand into the cell. The ligand may be, for example, an antibody, a humanized antibody, a recombinant single chain variable region fragment of an antibody, or a disulfide stabilized variable region fragment. The ligand may selectively bind to a peptide derived from human pIgR (SEQ ID NO:1), which peptide is selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In one set of preferred embodiments, the ligand may bind to an epitope selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). In some embodiments of the method, the ligand may further be defined as having a binding component for selectively binding to pIgR and a biologically active component. The biologically active component is selected from the group consisting of a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. In one set of embodiments, the biologically active component can be a small molecule. The method can be used with respect to a mammalian cell, and especially where the cell is an epithelial cell. The organ of interest can be selected from the group consisting of a small intestine, a large intestine, a liver-biliary tree, a stomach, a salivary gland, a lung, a vagina, a uterus, a lacrimal gland, a mammary gland, a nasal passage, and a sinus. The invention further provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), which pIgR has an initial cleavage site which, upon initial cleavage has a stalk region, the method comprising binding the ligand to a region of the pIgR, with the provisos that (a) the ligand does not substantially bind to a form of secretory component which is the most abundant form present in the organ of interest under physiological conditions; (b) the ligand does not substantially bind to a stalk region of the pIgR; and (c) the ligand does not bind to an extracellular epitope within the first 31 amino acids that are cell membrane proximal to the initial cleavage site of the pIgR, thereby permitting introduction of the ligand into the cell. The invention additionally provides a method of transcytosing a ligand from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR), by attaching the ligand to a region of the pIgR, provided that (a) binding of the ligand reduces proteolytic cleavage of secretory component (SC) by at least one-third compared to the cleavage of SC from a cell in the absence of the ligand, and (b) the ligand does not substantially bind to a stalk of said pIgR remaining after proteolytic cleavage under physiological conditions, thereby permitting transcytosis of the ligand from the apical side to the basolateral side of the cell. The ligand can be, for example, an antibody, including a humanized antibody, a scFv (including a recombinant single chain variable region fragment of an antibody), and a disulfide stabilized variable region. The ligand can bind to a peptide derived from human pIgR (SEQ ID NO:1), selected from the group consisting of: Lys487-Arg603, Lys487-Glu607, Lys487-Val611, Lys487-Arg615, Lys487-Ala618, Cys520-Arg603, Cys520-Glu607, Cys520-Val611, Cys520-Arg615, Cys520-Ala618, Lys577-Arg603, Lys577-Glu607, Lys577-Val611, Lys577-Arg615, Lys577-Ala618, Ser574-Arg603, Ser574-Glu607, Ser574-Val611, Ser574-Arg615, Ser574-Ala618, Val560-Arg603, Val560-Glu607, Val560-Val611, Val560-Arg615, Val560-Ala618, Cys544-Arg603, Cys544-Glu607, Cys544-Val611, Cys544-Arg615, and Cys544-Ala618. In some preferred embodiments, the ligand binds to an epitope of pIgR selected from the group consisting of QDPRLF (SEQ ID NO:10), LDPRLF (SEQ ID NO:11), KAIQDPRLF (SEQ ID NO:12), LDPRLFADEREI (SEQ ID NO:13), DENKANLDPRLF (SEQ ID NO:14), RLFADEREI (SEQ ID NO:15), and LDPRLFADE (SEQ ID NO:16). In one group of embodiments of this method, the ligand is further defined as having a binding component for selectively binding to a region of pIgR and a biologically active component. The biologically active component can be a nucleic acid, a peptide, a protein, a radioisotope, a lipid, a carbohydrate, a peptidomimetic, an anti-inflammatory, an antisense oligonucleotide, an antibiotic, and an anti-infective. In one group of embodiments, the biologically active component is a small molecule. The animal can be a mammal, and the cell can be a mammalian cell, and preferably is an epithelial cell. The invention further provides a method of increasing the rate by which a first ligand which binds to secretory component (SC) is transcytosed from an apical to a basolateral side of a cell of an organ of interest in an animal, which cell expresses a polymeric immunoglobulin receptor (pIgR) from an apical surface by (a) binding the pIgR at the apical side of said cell with a second ligand, which second ligand inhibits proteolytic cleavage of SC by at least one-third, and further which second ligand does not substantially bind to a stalk remaining attached to the cell after proteolytic cleavage, and (b) binding the first ligand to the SC, thereby permitting transcytosis of the SC to which the first ligand has bound from the apical to the basolateral side of said cell. | 20050119 | 20080729 | 20050915 | 76433.0 | 0 | BELYAVSKYI, MICHAIL A | METHODS OF TARGETING AGENTS TO CELLS EXPRESSING THE POLYMERIC IMMUNOGLOBULIN RECEPTOR | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,038,995 | ACCEPTED | Vascular plug having composite construction | This invention relates to apparatus and methods for use in sealing a vascular puncture site, particularly sites of punctures that are the result of catheterization or other interventional procedures. In several of the preferred embodiments, the sealing device includes a sealing member and a tether. The sealing member generally performs the function of occupying a space in an incision, puncture, or other wound and sealing the space in the incision, puncture, or wound that it occupies, to prevent further blood flow. The tether is typically attached in some manner to the sealing member, and provides the user with the ability to withdraw the sealing member if necessary. In a particularly preferred form, the sealing device further includes a restraining member associated with the sealing member. The restraining member provides the ability to more securely restrain the sealing member to prevent it from migrating from the deployment location within a tissue tract. The restraining member may also provide an additional capability of manipulating the sealing member after deployment. | 1. A device for substantially sealing a wound that extends through tissue to an opening in a body lumen comprising: a restraining member comprising a first bioabsorbable material and defining an interior space therein, and a sealing member comprising a second bioabsorbable material at least partially located within the interior space of said restraining member. 2. The device of claim 1 further comprising a tether attached at a first end to said sealing member. 3. The device of claim 1, wherein said first bioabsorbable material is the same as said second bioabsorbable material. 4. The device of claim 1, wherein said first bioabsorbable material is selected from the group consisting of polyglycolic acid, polylactide, polyglycol-lactide acid, collagen, and hydrogel. 5. The device of claim 1, wherein said restraining member comprises a porous member. 6. The device of claim 5, wherein said restraining member comprises a material having a knit, braided or woven construction. 7. The device of claim 5, wherein said restraining member is a tubular fabric member and said sealing member is a coiled foam pad enclosed by said tubular fabric member. 8. The device of claim 7, wherein said coiled form pad comprises a hydrogel. 9. A method for substantially sealing a wound that extends through tissue to an opening in a body lumen, comprising: providing a sealing device comprising a hydrogel material, and deploying the sealing device in the wound. 10. The method of claim 9, wherein said sealing device comprises a restraining member comprising a first bioabsorbable material and defining an interior space therein, and a sealing member comprising a second bioabsorbable material at least partially located within the interior space of said restraining member. 11. The method of claim 10, wherein said sealing device further comprises a tether attached at a first end to said sealing member. 12. The method of claim 10, wherein said first bioabsorbable material is selected from the group consisting of polyglycolic acid, polylactide, polyglycol-lactide acid, collagen, and hydrogel. 13. The method of claim 10, wherein said restraining member comprises a material having a knit, braided or woven construction. 14. The method of claim 13, wherein said restraining member is a tubular fabric member and said sealing member is a coiled foam pad enclosed by said tubular fabric member. 15. The method of claim 14, wherein said coiled form pad comprises a hydrogel. 16. A device for substantially sealing a wound that extends through tissue to an opening in a body lumen comprising: a sealing member, at least a portion of which having a first radial dimension for delivery of said sealing member into the wound and a second radial dimension upon delivery into said wound and exposure to fluid flow associated with said wound, the second radial dimension being larger than the first radial dimension, and wherein said sealing member comprises a hydrogel. 17. The device of claim 16, further comprising a tether connected to said sealing member and having a length sufficient to extend externally of said wound after delivery of the sealing member. 18. The device of claim 17, further comprising a stop member at a terminal end of said tether, said stop member adapted to retain the sealing member on the tether. 19. The device of claim 17, further comprising a first endcap located on the tether on a first side of said sealing member, and a second endcap located on the tether at a second side of said sealing member. 20. The device of claim 16, wherein said sealing member comprises a plurality of disc-shaped members. 21. The device of claim 16, further comprising a restraining member comprising a 10 first bioabsorbable material and defining an interior space therein, said sealing member being located at least partially within the interior space of said restraining member. 22. The device of claim 21, wherein said first bioabsorbable material is selected from the group consisting of polyglycolic acid, polylactide, polyglycol-lactide acid, collagen, and hydrogel. | RELATED APPLICATION This patent application is a continuation-in-part of U.S. patent application Ser. No. 10/142,735, filed May 10, 2002, which is a continuation-in-part of U.S. patent application Ser. No. 09/866,548, filed May 25, 2001, which is a continuation-in-part of U.S. patent application Ser. No. 09/738,431, filed Dec. 14, 2000, the disclosures of which are expressly incorporated by reference herein. FIELD OF THE INVENTION The present invention relates generally to apparatus and methods for sealing or closing passages through tissue, and more particularly to devices for sealing punctures or other openings communicating with body lumens, such as blood vessels. BACKGROUND OF THE INVENTION Catheterization and interventional procedures, such as angioplasty or stenting, generally are performed by inserting a hollow needle through a patient's skin and muscle tissue into the vascular system. A guide wire may then be passed through the needle lumen into the patient's blood vessel accessed by the needle. The needle may be removed, and an introducer sheath may be advanced over the guide wire into the vessel, e.g., in conjunction with or subsequent to a dilator. A catheter or other device may then be advanced through a lumen of the introducer sheath and over the guide wire into a position for performing a medical procedure. Thus, the introducer sheath may facilitate introduction of various devices into the vessel, while minimizing trauma to the vessel wall and/or minimizing blood loss during a procedure. Upon completion of the procedure, the devices and introducer sheath may be removed, leaving a puncture site in the vessel wall. External pressure may be applied to the puncture site until clotting and wound sealing occur. This procedure, however, may be time consuming and expensive, requiring as much as an hour of a physician's or nurse's time. It is also uncomfortable for the patient, and requires that the patient remain immobilized in the operating room, catheter lab, or holding area. In addition, a risk of hematoma exists from bleeding before hemostasis occurs. Various apparatus have been suggested for percutaneously sealing a vascular puncture by occluding the puncture site. For example, U.S. Pat. Nos. 5,192,302 and 5,222,974, issued to Kensey et al., describe the use of a biodegradable plug that may be delivered through an introducer sheath into a puncture site. When deployed, the plug may seal the vessel and provide hemostasis. Such devices, however, may be difficult to position properly with respect to the vessel, which may be particularly significant since it is generally undesirable to expose the plug material, e.g., collagen, within the bloodstream, where it may float downstream and risk causing an embolism. Another technique has been suggested that involves percutaneously suturing the puncture site, such as that disclosed in U.S. Pat. No. 5,304,184, issued to Hathaway et al. Percutaneous suturing devices, however, may require significant skill by the user, and may be mechanically complex and expensive to manufacture. Staples and surgical clips have also been suggested for closing wounds or other openings in tissue. For example, U.S. Pat. Nos. 5,007,921 and 5,026,390, issued to Brown, disclose staples that may be used to close a wound or incision. In one embodiment, an “S” shaped staple is disclosed that includes barbs that may be engaged into tissue on either side of the wound. In another embodiment, a ring-shaped staple is disclosed that includes barbs that project from the ring. These staples, however, have a large cross-sectional profile and therefore may not be easy to deliver through a percutaneous site to close an opening in a vessel wall. U.S. Pat. No. 6,033,427, issued to Lee, discloses a method and device for sealing internal puncture sites which, in one embodiment, uses a dual lumen bleed back system in which the distal bleed back ports are axially spaced from each other such that when the obturator is in a certain location, there will be bleed back through one of the lumens, but not through the other. In addition, skin seals have been proposed that may be threaded into an opening in skin. For example, U.S. Pat. No. 5,645,565, issued to Rudd et al., discloses a surgical plug that may be screwed into a puncture to seal the puncture. The surgical plug includes an enlarged cap and a threaded shaft that extends from the cap. During an endoscopic procedure, the plug may be threaded into an opening through skin until the cap engages the surface of the skin. The plug is intended to seal the opening communicating with a body cavity to prevent insufflation fluid from leaking from the cavity. Such plugs, however, may only be used at the surface of the skin, and may not be introduced through tissue, for example, to seal an opening in the wall of a blood vessel or other subcutaneous region. Various methods and means for determining the location of the distal end of a closure device have been proposed, including “bleed back” methodology such as that disclosed in U.S. Pat. No. 4,738,658 issued to Magro et al. However, prior bleed back devices have been constructed such that blood flow out of the patient continues for a longer period of time during deployment of the sealing means than would be desirable. A further development in bleed back technology is disclosed in published U.S. Patent Application 2004/0019330, in which a control element having an enlarged distal end is used both to control blood flow through the blood vessel puncture and to provide an indication of the position of the distal end of an introducer sheath by withdrawing the enlarged distal end from the lumen of the blood vessel into the puncture in the wall of the blood vessel such that bleed back is, according to this published application, stopped. Leschinsky U.S. Pat. No. 5,871,501 discloses the use of an anchor on a guide wire to provide an indication of the location of the wall of a blood vessel to assist in the placement of a hemostatic material to block flow of blood out of a puncture in the vessel. Although these and other methods and devices have been proposed for deploying a plug to prevent blood flow from a puncture in a blood vessel, a need remains for a safe and effective device and method for deploying a plug for this purpose, and for plugs that are more easily deployed and that provide improved prevention of blood flow. SUMMARY OF INVENTION The present invention is directed to improved vascular sealing devices used to seal incisions and/or punctured blood vessels, and to methods of using the devices as well. The vascular sealing devices are particularly useful for sealing incisions and punctures that result from catheterization or interventional procedures, such as angioplasty or stenting, although they are not limited to such uses. These incisions and punctures are commonly made to the femoral artery, and the devices described herein are particularly adapted for these purposes. It should be understood, however, that the devices may also be used to seal incisions and/or punctures in other blood vessels or organs. In several of the preferred embodiments, the sealing device includes a sealing member and a tether. The sealing member generally performs the function of occupying a space in an incision, puncture, or other wound and sealing the space in the incision, puncture, or wound that it occupies, to prevent further blood flow. The tether is typically attached in some manner to the sealing member, and provides the user with the ability to withdraw the sealing member if necessary. In certain embodiments, the tether also provides the user with the ability to manipulate the sealing member for desired effect, such as to radially expand the sealing member within the incision. In a particularly preferred form, the sealing device further includes a restraining member associated with the sealing member. The restraining member provides the ability to more securely restrain the sealing member to prevent it from migrating from the deployment location within a tissue tract. The restraining member may also provide an additional capability of manipulating the sealing member after deployment. In several preferred embodiments, it is desirable to have the sealing member material expand when the sealing member is deployed and exposed to blood flow from the target vessel. This expansion may cause the sealing member, and therefore the sealing device, to expand radially upon deployment and to thereby engage the incision tissue more firmly, thus tending to prevent migration of the sealing device and increase the effectiveness of the seal. The sealing device may take any of a variety of different forms or shapes depending upon the nature of the intended use, the material used to make up the device, and other factors. For example, the sealing device may take the form of an undefined mass in situations where the size and/or shape of the sealing device is not a priority or where the sealing portion of the device is restrained by a restraining portion. In another example, the sealing device takes the form of a disc that is adapted to occupy an incision or puncture wound. Other examples include multiple-disc sealing members, and a pair of discs serving as endcaps to a separate tube shaped member. Still further examples include a solid or rolled tube and a mechanical flower. Other and further shapes and sizes are possible, as is any combinations of these shapes and sizes. Preferably, the tether is attached to the sealing member and is adapted to extend proximally from the sealing member, through and out of the incision, thereby allowing for manipulation by the user. The tether may be used to adjust the sealing member after its deployment, such as by increasing the effective radial dimension of the sealing member, or to remove the sealing member altogether if necessary. In several preferred embodiments, the sealing device has a composite structure that includes one or more sealing members, as described above, and one or more restraining members. Preferably, the restraining member provides the ability to more easily deliver a sealing member and the ability to reduce the likelihood that the sealing member will migrate after its deployment. In a particular preferred form, the restraining member comprises a braided “sock” that encloses the sealing member and allows the sealing member to be more easily delivered to an incision tract. In several preferred embodiments, the sealing member, restraining member, and the tether of the vascular sealing device are preferably formed of bioabsorbable materials such as collagen, polyglycolic acids (PGAs), polylactides (PLAs), hydrogel, or gel-foam. These materials may be provided in solid, gel, foam, felt, or other forms. Of these, hydrogels, such as hydroxypropyl cellulose (HPC) hydrogels, are particularly preferred to be used to make the sealing member due to several of their physical properties. In particular, hydrogels are highly absorbent and exhibit high mechanical strength after absorbing a large amount of liquid. In several alternative embodiments, the sealing device has a composite structure that includes one or more sealing members, as described above, and one or more restraining members. In the alternative embodiments, either the sealing member or the restraining member is formed of a non-bioabsorbable material, while the other member is formed of a bioabsorbable material. Thus, in the alternative embodiments, a bioabsorbable sealing member may be associated with a non-bioabsorbable restraining member, or a non-bioabsorbable sealing member may be associated with a bioabsorbable restraining member. Examples of non-bioabsorbable materials suitable for use in the sealing member or restraining member include nylon, stainless steel, ceramic materials, titanium, gold, platinum, nickel, nickel-titanium alloys, other metals and metal alloys, and other conventional materials suitable for medical use. For example, the restraining member may be formed of a nylon mesh, or of a mesh or braids of stainless steel filaments. The vascular sealing devices described herein may be deployed by any suitable mechanism. One such mechanism particularly adapted for deploying such devices in an incision created by a catheterization or interventional procedure is described in co-pending U.S. patent application Ser. No. 10/850,795, entitled “Locator and Delivery Device and Method of Use,” filed on May 21, 2004, and assigned to Ensure Medical, Inc., the assignee herein. The foregoing application is hereby incorporated by reference in its entirety as if fully set forth herein. The descriptions herein are particularly directed to sealing puncture wounds created during catheterization or interventional procedures, particularly to such wounds in the femoral artery, but it is to be understood that the vascular sealing devices of the present invention can be used to seal other blood vessels and puncture wounds in them. With that understanding, we turn to a more detailed description of the preferred embodiments. DESCRIPTION OF THE DRAWINGS FIG. 1A is an illustration of a vascular sealing device according to the present invention. FIG. 1B is an illustration of the device shown in FIG. 1A, shown in an expanded state. FIG. 2B is an illustration of the device shown in FIG. 2A, shown in an unexpanded state. FIG. 2C is an illustration of the device shown in FIG. 2A, shown in an expanded state. FIG. 3A is an illustration of another vascular sealing device according to the present invention, shown within a delivery tube prior to deployment. FIG. 3B is an illustration of the vascular sealing device shown in FIG. 3A, shown after deployment by a delivery tube. FIG. 3C is an illustration of the vascular sealing device shown in FIG. 3A, shown after alignment and compression of the discs contained on the device. FIG. 4A is an illustration of another vascular sealing device according to the present invention, shown after deployment by a delivery tube. FIG. 4B is an illustration of the vascular sealing device shown in FIG. 4A, shown after compression of the end caps contained on the device. FIG. 5A is an illustration of another vascular sealing device according to the present invention. FIG. 5B is an illustration of a process for loading the sealing device shown in FIG. 5A into a delivery tube. FIG. 5C is an illustration of a the sealing device shown in FIG. 5A, shown after deployment from the delivery tube. FIG. 5D is an illustration of a process for making another vascular sealing device according to the present invention. FIG. 5E is an illustration of a vascular sealing device that is the product of the process shown in FIG. 5D. FIG. 5F is an illustration of the vascular sealing device shown in FIG. 5E, shown as loaded into a delivery tube. FIG. 5G is an illustration of the vascular sealing device shown in FIG. 5E, shown after deployment from the delivery tube. FIG. 6A is an illustration of another vascular sealing device according to the present invention. FIG. 6B is an illustration of the device shown in FIG. 6A, shown in an expanded state. FIG. 7A is an illustration of another vascular sealing device according to the present invention. FIG. 7B is an illustration of the device shown in FIG. 7A, shown in an expanded state. FIG. 8A is an illustration of another vascular sealing device according to the present invention. FIG. 8B is an illustration of the vascular sealing device shown in FIG. 8A, shown in an expanded state. FIG. 9A is an illustration of a pad used as a starting material for a sealing member. FIG. 9B is an illustration of a process for compressing the pad shown in FIG. 9B. FIG. 9C is an illustration the pad shown in FIG. 9A, after compression, shown partially rolled into a coiled form. FIG. 9D is an illustration of a tube of braided material suitable for use as a restraining member according to the present invention. FIG. 9E is an illustration of part of a process of inserting the pad shown in FIG. 9A in its coiled form into the tube shown in FIG. 9D. FIG. 9F is an illustration of a vascular sealing device according to the present invention. FIG. 9G is an illustration of the device shown in FIG. 9F, shown in an expanded state. FIG. 9H is an illustration of a vascular sealing device similar to that shown in FIG. 9F, further including a separate tether member. FIG. 9I is an illustration of the device shown in FIG. 9H, shown in an expanded state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1A and 1B are rudimentary illustrations of a vascular sealing device in accordance with the present invention. The device 20 includes a sealing member 22 retained on a tether 24. The sealing member 22 is preferably retained on the tether 24 at or near its distal end point by a stop member 26 formed at the distal end of the tether 24. The stop member 26 is preferably a knot formed at the distal end of the tether 24. FIG. 1A shows the device in its unexpanded, predeployment state. FIG. 1B shows the device after it has expanded due to fluid exposure. The sealing member 22 is formed from a material that is able to expand, or to be expanded, once the sealing device 22 is deployed for use. The sealing member is preferably formed from a bioabsorbable material, but, in several alternative embodiments, the sealing member may be formed from a non-bioabsorbable material. Examples of suitable bioabsorbable materials include bioabsorbable collagen, polyglycolic acids (PGAs), polylactides (PLAs), polyglycol-lactides (PGLAs), hydrogels, and gel-foams. These materials may be provided in solid, gel, foam, felt, or other forms as appropriate for the particular application. Of these materials, hydrogels are particularly preferred due to several of their physical properties. A hydrogel is an absorbent, microporous gel comprising a crosslinked polymer having interconnected fluid cells distributed throughout its mass. Hydrogels absorb fluids very quickly, and exhibit high mechanical strength even after absorbing large amounts of fluids. Moreover, hydrogels typically expand isotropically, meaning that they are able to maintain their original shapes during and after expansion due to fluid absorption. Additional information relating to hydrogels suitable for use in the vascular sealing devices described herein can be found in U.S. Pat. Nos. 5,573,994 and 6,030,442, each of which is incorporated herein by reference in its entirety as if fully set forth herein. Examples of nonbioabsorbable materials that may be used to form the sealing member 22 include nylon, stainless steel, ceramic materials, titanium, gold, platinum, nickel, nickel-titanium alloys, other metals and metal alloys, and other conventional materials suitable for medical use. The sealing member 22 of the device shown in FIG. 1A has a generally tubular shape that surrounds the tether 24 near its end. The sealing member 22 may be loosely or firmly secured to the tether 24 by conventional means, or it may be allowed to slide along at least a portion of the length of the tether 24. The tether 24 shown in the FIG. 1A sealing device performs at least the function of providing the user the ability to retrieve the sealing device 20 from its deployed state if necessary. The tether 24 is preferably formed of conventional suture material, such as a biodegradable polymer having sufficient tensile strength to perform the above functions. Examples of such materials include PGA, PLA, and PGLA polymers. Alternatively, the tether may be formed of a non-bioabsorbable material such as those described above. The stop member 26 shown in the FIG. 1A sealing device performs at least the function of retaining the sealing member 22 on the tether 24. The stop member 26 may be formed of any biocompatible material suitable to perform this purpose. Alternatively, as in the device 20 shown in FIGS. 1A and 1B, the stop member 26 may comprise a knot formed at the end of the tether 24. The sealing device 20 is particularly adapted to be used to seal an incision, puncture, or other wound found in the body of a patient, typically a human or other mammal. The device 20 may be delivered to the wound site by any suitable means. For example, in the case of an incision created to gain access to the femoral artery for a catheterization or other interventional procedure, the device may be delivered to the incision tract using the delivery device described in co-pending U.S. patent application Ser. No. 10/850,795, entitled “Locator and Delivery Device and Method of Use,” filed on May 21, 2004, and assigned to Ensure Medical, Inc., the assignee herein (hereinafter referred to as “the '795 application”). The delivery device described in the '795 application is adapted to deliver a vascular plug or other sealing device in an incision tract to a point proximal to the blood vessel. In the case of the vascular sealing device 20 shown in FIG. 1A herein, once deployed, the sealing member 22 is exposed to blood flow from the blood vessel. This exposure causes the sealing member 22 to expand due to absorption of the blood, as shown in FIG. 1B. This expansion of the sealing member 22, which has been inserted into the incision tract, causes the sealing member 22 to lodge itself firmly in the incision tract, thereby preventing the sealing device 20 from migrating out of position and creating an effective seal that prevents blood flow from the vessel. The components making up the sealing device 20 may be formed entirely of bioabsorbable materials, or they may be formed of a combination of bioabsorbable and non-bioabsorbable materials. For example, the sealing member 22 may be formed of one or more bioabsorbable materials, while the tether 24 is formed of a nonbioabsorbable material. Other combinations are also possible. Optionally, a clotting agent or other hemostasis promoting material—such as a thromboplastin or other conventional clotting agent—may be incorporated into, added to, or used in combination with the sealing device 20. FIGS. 2A through 2C show an alternative embodiment of a vascular sealing device 20 in which the tether 24 is used to enclose and retain the sealing member 22. With reference to FIG. 2A, the device 20 includes a sealing member 22 and a tether 24. The sealing member 22 and tether 24 may be formed of any of the same materials described above in relation to the sealing device 20 shown in FIGS. 1A and 1B. The tether 24 is formed in a surgical knot 25 at its distal end in order to loosely enclose the sealing member 22. In FIG. 2B, the device 20 is shown with the surgical knot 25 snugged in order to more firmly enclose and retain the sealing member 22 prior to deployment of the device. Upon deployment into an incision tract, the sealing member 22 comes into contact with blood flowing from a vessel and expands, providing a seal, as shown in FIG. 2C. Turning to FIGS. 3A through 3C, an alternative embodiment of a vascular sealing device 20 includes a number of disc-shaped sealing member 22a-d that are slidably attached to the end of a tether 24. A stop member 26, preferably a knot formed at the distal end of the tether, retains the sealing members 22a-c on the tether 24. The disc-shaped sealing members 22a-d and tether 24 may be formed of any of the same materials described above in relation to the sealing device 20 shown in FIGS. 1A and 1B. Turning first to FIG. 3A, the sealing device 20 is shown loaded into a delivery device 100, the distal end of which is shown in the Figure. The delivery device has a cylindrical delivery tube 102, shown in cross-section in FIG. 3A, which in turn has an opening 104 at its distal end. The internal space defined by the interior of the delivery tube 102 is adapted to receive and retain the sealing device 20 for delivery to an incision. Once the delivery device 100 is placed into the incision at the appropriate location for delivery of the sealing device 20, the sealing device 20 is deployed through the opening 104 (by a plunger, by retraction of the delivery tube 102, or by another mechanism associated with the delivery device) and into the incision tract, adjacent to the blood vessel opening. As shown in FIG. 3A, the disc-shaped sealing members 22a-c are spaced apart slightly on the tether 24 in order to be slanted at an angle relative to the axis defined by the tether 24 as they are loaded into and retained within the delivery device. This slanting reduces the radial profile of the disc-shaped sealing members 22a-c, allowing them to be loaded into a smaller diameter delivery tube than would be needed if the sealing members 22a-c were loaded without the slant. FIG. 3B shows the sealing device 20 after delivery within an incision tract and withdrawal of the delivery device 100. At this point, the sealing members 22a-d remain in the slanted, spaced-apart orientation that they occupied within the interior of the delivery tube 102. Also at this point, the disc-shaped sealing members 22a-d are exposed to blood flow and begin to expand. As shown in FIG. 3C, it is possible and desirable to align and compress the individual disc-shaped sealing members 22a-c by backing the delivery tube 102 up against the most proximally located disc 22d, and pulling on the tether 24 (see arrow “A” in FIG. 3B) to cause the individual discs 22a-d to align and compress against one another while being retained on the tether 24. The effect is to form a radially compressed sealing member 22a-d having an effectively larger radial dimension. The compressed sealing member 22a-d is thereby lodged firmly within the incision tract, seals the tract against blood flow from the blood vessel, and promotes hemostasis. FIGS. 4A and 4B show still another alternative embodiment of the sealing device 20. In this embodiment, the device includes a sealing member 22 formed as a tube that surrounds a portion of a tether 24. A first endcap 28 is attached to the end of the tether 24, and a second endcap 29 is slidably attached to the tether 24 just proximally of the tubular sealing member 22. The tubular sealing member 22 and tether 24 may be formed of any of the same materials described above in relation to the sealing device 20 shown in FIGS. 1A and 1B. The end caps 28 and 29 are preferably in the form of solid or semi-solid discs. The end caps may be formed of either a bioabsorbable material or a non-bioabsorbable material. In the preferred embodiment, the end caps are formed of a bioabsorbable material, preferably polymeric. The device 20 shown in FIGS. 4A and 4B may be delivered with a delivery device 100 as shown in FIG. 4A. The device 20 may be expelled from the delivery tube 102 through the opening 104 at its distal end by a plunger 106, or, alternatively, the delivery tube 102 is withdrawn from around the sealing device 20 as the sealing device 20 is retained in place in an incision tract. In either case, the sealing device 20 and delivery device 100 are separated, leaving the sealing device in place within an incision tract. After delivery, the sealing device 20 may be compressed in a manner similar to that described above in relation to FIGS. 3A through 3C. In reference to FIG. 4B, the plunger 106, the delivery tube 102, or some other member may be placed against the second endcap 29 to provide a back up, and the tether 24 is then drawn taught (see arrow “A”) in order to drive the two endcaps 28, 29 toward one another and compress the tubular sealing member 22. Alternatively, the tether 24 may be simply held taut, and the second endcap 29 is then forced down toward the first endcap 28 by the plunger 106, the delivery tube 102, or other member (see arrows “B”), compressing the tubular sealing member 22 in the process. In either event, the end result is that shown in FIG. 4B, with the tubular sealing member 22 compressed radially (see arrows “E”) to cause the sealing device to lodge firmly in the incision tract and to provide a seal against blood flow from the blood vessel. Turning next to FIGS. 5A through 5G, a still further alternative embodiment of the sealing device 20 is shown. In reference to FIG. 5A, the sealing device 20 includes a pair of disc-shaped sealing members 22a-b that are attached to a tether 24 near its distal end. The disc-shaped sealing members 22a-b and tether 24 may be formed of any of the same materials described above in relation to the sealing device 20 shown in FIGS. 1A and 1B. Moreover, although two disc-shaped sealing members 22a-b are shown in the Figures, more or fewer disc-shaped sealing members may be provided. As shown in the Figures, the discs are separated by only a small amount of space, unlike the embodiment shown in FIGS. 3A-B. Therefore, as shown in FIG. 5B, in order to load the disc-shaped sealing members 22a-b into the delivery tube 102 of a delivery device 100 (see arrow “L” in FIG. 5B), the disc-shaped sealing members 22a-b are compressed radially during the loading process (see arrows “C” in FIG. 5B). In many cases, one result of this radial compression is that the disc-shaped sealing members 22a-b remain in their compressed state after delivery, i.e., after exiting the delivery tube 102. This effect is illustrated in FIG. 5C, where a plunger 106 associated with the delivery device 100 is shown deploying the sealing device 20 by applying a force (see arrows “F”) on the proximal end of the plunger 106. After deployment, the radial dimension (see arrows “d”) of the sealing members 22a-b of the sealing device 20 is approximately the same as the inner diameter of the delivery tube 102 (arrows “d”). This effect may be problematic in cases in which the disc-shaped sealing members 22a-b are formed of a material that does not expand significantly upon deployment in an incision tract, and in cases in which the tissue in which the incision tract is formed has become inelastic due to, for example, multiple sheath exchanges during any surgical procedures. In those cases, the sealing member 22a-b will tend to have a radial dimension (effective diameter) that may be slightly smaller than the diameter of the incision, and the tissue surrounding the incision has insufficient elasticity to adequately collapse around the sealing member 22a-b to cause it to firmly lodge in place. One solution proposed herein is to provide a volumetric expansion member in association with the sealing member. One example is shown in FIGS. 5D through 5G. Turning to FIG. 5D, each of the pair of disc-shaped sealing members 22a-b is provided with a cylindrical void space at its center. The sealing members 22a-b are preferably formed from a material that demonstrates a relatively small amount of expansion when exposed to fluids in comparison to the expansion capability of the hydrogels described above. An example of a suitable material is a PGA felt material. A separate volumetric expansion member 30 is dimensioned to be inserted into the void space formed in the sealing member 22a-b. As shown in FIG. 5D, the expansion member 30 may be formed as a rolled sheet of highly expandable material, such as a hydrogel foam pad, that is formed to surround the tether 24. The expansion element 30 may then be inserted into the void space formed in the sealing element 22a-b, as shown, for example, in FIG. 5E. The sealing device 20 is then loaded into a delivery device, as shown in FIG. 5F. The delivery device 100, like those described elsewhere herein, includes a delivery tube 102 and a plunger 106 adapted to expel the sealing device 20 through the opening 104 at the distal end of the delivery device 100, or to maintain the position of the sealing device 20 while the delivery tube 102 is withdrawn. Upon deployment, the sealing member 22a-b, including the volumetric expansion member 30, is exposed to blood flow from the blood vessel. Whereas the disc-shaped sealing members 22a-b tend only to expand slightly upon exposure to fluids, the expansion member associated with the sealing member 22a-b expands radially to a much greater degree, as illustrated by arrows “E” in FIG. 5G. This enhances the expansion of the disc-shaped sealing members 22a-b, causing the sealing member 22a-b to more effectively seal the incision tract against further blood flow and to promote hemostasis. Although a particular orientation of the volumetric expansion member 30 in relation to the sealing member 22a-b is illustrated in FIGS. 5D through 5G, it should be understood that other and different orientations are also possible. For example, the volumetric expansion member may be provided on the exterior of the sealing member, or it may be embedded elsewhere within the sealing member. The expansion member may also take on forms other than a rolled sheet, and the sealing member may take on forms other than the disc-shaped members shown in the Figures. These and other variations are possible while obtaining the advantages provided by a composite structure including one or more sealing members formed from a first material, and one or more volumetric expansion members formed from a second material having substantially greater expansion capacity than the first material. The sealing members and volumetric expansion members may be formed entirely of a combination of bioabsorbable materials, or by a combination of bioabsorbable materials and non-bioabsorbable materials. Turning next to FIGS. 6A and 6B, an additional embodiment of a sealing device 20 includes a sealing member 22 in the form of a mechanical flower. The sealing member 22 is preferably formed of a hydrogel or any of the other materials described herein. The mechanical flower includes a number of petals 32 that project radially away from the core 34 of the flower. A tether 24 is attached to the core 34 and is adapted to extend out of an incision upon deployment of the sealing device 20 in an incision tract. The shape of the mechanical flower is selected due to its capacity for expanding after deployment and exposure to blood flow. For example, as shown in FIG. 6A, prior to deployment (as, for example, while loaded in a delivery device 100), the mechanical flower may be compressed such that all of the petals 34 extend in a single general direction and each is in close proximity the others. Upon deployment, however, the mechanical flower is allowed to “bloom,” i.e., to expand such that the petals 34 separate from one another, as shown, for example, in FIG. 6B. This expansion may be caused by a combination of release from the confines of the delivery device and the expansion attributable to the exposure of the superabsorbent sealing member 22 to blood flow in the incision tract 50. This expansion provides the capability for the sealing device to lodge firmly within a tissue tract and to seal the tract against blood flow from the blood vessel 52. Turning next to FIG. 7, an alternative embodiment of the sealing device 20 includes a collection of individual fibers 36 secured by a center tie 38. The fibers 36 are preferably formed of an hydrogel or other expansive material such as those discussed herein. The center tie 38 is also formed of one of the materials described above, but preferably a more rigid material to provide a secure attachment to the collection of fibers 36 making up the sealing member 22. A tether 24 extends from the center tie 38 and outward from an incision tract once the sealing device 20 is deployed. A construction of the sealing device that is particularly preferred is a composite construction that includes a tether, a sealing member, and a separate restraining member. One example of this structure is shown in the embodiment illustrated in FIGS. 8A and 8B. In this embodiment, the sealing member 22 preferably comprises a bundle or other body of a material such as a hydrogel or other of those materials discussed herein. The sealing member 22 may be in the form of a felt, a gel, a foam, or other solid or semi-solid material. The sealing member 22 is enclosed and retained by a restraining member 40. In the embodiment shown in FIGS. 8A and 8B, the restraining member 40 comprises a porous basket, such as a knit, braided, or woven fabric that encloses and/or encapsulates the sealing member 22. The restraining member 40 preferably is formed from a material that is porous but fairly rigid and/or that has fairly high tensile strength in order to adequately restrain the sealing member 22. The restraining member may comprise a fairly loose knit, a braided structure, a tightly-woven fabric, or something in between. Preferably, both the sealing member 22 and the restraining member 40 are formed from bioabsorbable materials. In alternative embodiments, however, one of the sealing member 22 and the restraining member 40 is formed of a bioabsorbable material, while the other is formed from a non-bioabsorbable material. Suitable bioabsorbable and non-bioabsorbable materials are those described above. The restraining member 40 shown in FIGS. 8A and 8B includes a mechanism for selectively compressing and radially expanding the sealing member 22 enclosed within the restraining member 40. The mechanism includes a cinch line 42 that runs through a channel 44 formed on the upper periphery of the restraining member 40. A snare knot 46 is formed on the cinch line 42 in the channel 44 and provides the ability to draw the cinch line tight in order to compress the sealing member 22 enclosed in the restraining member 40. When the cinch line 42 is drawn tight (see arrows “T” in FIG. 8B), it changes the shape of the porous basket forming the restraining member 40 by reducing its height, causing the volume of the sealing member 22 enclosed within the restraining member 40 to expand radially, as shown in FIG. 8B. The material making up the restraining member 40 is preferably constructed in such a way to facilitate this change of shape, such as by providing a looser or more flexible braided, woven, or knit structure along the sides of the restraining member 40. The cinch line 42 and snare knot 46 may be accessible by way of the tether 24, or by a separate line that extends from the restraining member 40. The sealing device 20 shown in FIGS. 8A and 8B may be deployed in a manner similar to those described elsewhere herein. For example, the sealing device 20 may be deployed in an incision tract by using a delivery device having a delivery tube that expels the sealing device 20 from its distal end once properly located within the incision tract. Once deployed, the sealing device 20 will encounter blood flow from the vessel being sealed, thereby causing the sealing member 22 enclosed by the restraining member 40 to expand, including radial expansion. In addition, the user may selectively tighten the cinch line 42 to compress the sealing member 22 to provide additional radial expansion. In this way, the sealing device 20 may be expanded to firmly lodge the device within the incision tract to prevent its migration out of the tract and to seal the tract against blood flow. Turning to FIGS. 9A through 9I, an additional embodiment of a sealing device is shown, as is a method of making the sealing device. The sealing device shown in FIGS. 9A through 9I is constructed to include a tether, a sealing member, and a restraining member. Turning first to FIG. 9A, in the preferred embodiment the sealing member 22 is a hydrogel foam pad, although other bioabsorbable, highly-expandable materials may be used as well. In other embodiments, the sealing member 22 may be formed from a non-bioabsorbable material. The foam pad preferably has dimensions that allow it to be compressed and rolled (as described below) to a shape and size suitable for receipt in a delivery device and for its ultimate use as a sealing device in an incision tract. In order to optimize the volume and capacity of the sealing member 22, it is preferable to compress the foam pad prior to installation in the sealing device. One method of performing this compression step is to use a compressive roller 110 to apply a compressing force to the pad, much like a rolling pin. This method is illustrated by arrow “R” in FIG. 9B. The result of the compression step is to obtain a highly compressed, flat foam pad of hydrogel or other bioabsorbable (or non-bioabsorbable) material. Turning to FIG. 9C, in the preferred embodiment, the sealing member is rolled into a coil. The coil shape is preferred because it creates a low-profile sealing member in the dry state that is capable of a high degree of radial expansion when the sealing member is exposed to blood flow. The low profile in the dry state is useful to facilitate delivery of the sealing device, while the high degree of radial expansion when exposed to fluid is useful to facilitate firmly lodging the sealing device in an incision tract and sealing the tract against blood flow. Other and different shapes and dimensions are also possible, and each may contribute more or less to these objectives. For example, the sealing member may be a wadded or otherwise compressed mass. The coiled sheet shape is a preferred embodiment. FIG. 9D shows a preferred restraining member 40 for use with the sealing device. The restraining member 40 is a porous, tubular member formed of a knit, woven, or braided material. The composition of the tubular restraining member 40 is preferably of a bioabsorbable material, such as suture material formed from PGA, PLA, or PGLA. In alternative embodiments, the restraining member 40 may be formed of a non-bioabsorbable material, such as nylon or stainless steel filament mesh. The knit or braided structure allows the restraining member 40 to expand when needed to accommodate the sealing member 22 within its interior. FIG. 9E provides an illustration of a process for inserting the sealing member 22, in this case a compressed and coiled sheet of hydrogel material, into the restraining member 40. The arrow “A” indicates passage of the sealing member 22 into the interior space defined by the restraining member 40, within which the sealing member is enclosed and retained. As shown in the Figure, the woven, braided, or knit structure of the restraining member 40 material allows for expansion of the restraining member 40 to accommodate the sealing member 22. After inserting the sealing member 22 into the restraining member 40, the open end of the restraining member 40 (through which the sealing member has passed) may be closed or sealed to fully enclose the sealing member 22, as shown in FIG. 9F. In addition, a proximal portion 41 of the restraining member 40 that extends proximally of the sealing member 22 may be used instead of, or as a replacement for, a tether as used in other embodiments described herein. Thus, after deployment of the sealing device 20, the proximal portion 41 of the restraining member 40 would extend out of the incision tract and may be used to manipulate the sealing device 20 and/or to remove the sealing device 20 from the incision if necessary. FIG. 9F illustrates one embodiment of the complete sealing device 20 in its predeployment, unexpanded state. This state, in which the sealing device 20 has a reduced profile, is suitable for loading the device 20 into an appropriate delivery device, such as the delivery devices described previously herein. The sealing device is then able to be delivered by, for example, expelling the device out of the open distal end of a delivery tube, into an incision tract and near an opening in a target blood vessel. Upon exposure to blood flow, the sealing member 22 within the sealing device will expand, as illustrated by the arrows “E” in FIG. 9G. This expansion will cause the sealing device 20 to lodge firmly within the incision tract, sealing the incision against blood flow. FIGS. 9H and 9I show a sealing device 20 similar to that described above in relation to FIGS. 9F and 9G, but also including a tether 24. The tether 24 is preferably attached to the sealing member 22 and the restraining member 40, and may be used to manipulate the sealing device 20 after deployment, or to remove the sealing device 20 from the incision if necessary. For example, as shown in FIG. 91, the tether 24 may be attached to the sealing member 22 and restraining member 40 in a manner that allows the user to exert an upward force (see arrows “F”) on the tether that increases the radial expansion (arrows “E”) of the sealing member 22 inside the restraining member 40. This increased radial expansion due to mechanical manipulation of the sealing device will increase the ability of the device to lodge firmly within the incision tract, seal the incision against blood flow, and promote hemostasis. As noted above, the several embodiments of the sealing device described herein are preferably constructed of components formed entirely from bioabsorbable materials. However, each of the foregoing embodiments may also be constructed of a combination of one or more components formed from bioabsorbable materials, and one or more components formed from non-bioabsorbable materials. While the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Catheterization and interventional procedures, such as angioplasty or stenting, generally are performed by inserting a hollow needle through a patient's skin and muscle tissue into the vascular system. A guide wire may then be passed through the needle lumen into the patient's blood vessel accessed by the needle. The needle may be removed, and an introducer sheath may be advanced over the guide wire into the vessel, e.g., in conjunction with or subsequent to a dilator. A catheter or other device may then be advanced through a lumen of the introducer sheath and over the guide wire into a position for performing a medical procedure. Thus, the introducer sheath may facilitate introduction of various devices into the vessel, while minimizing trauma to the vessel wall and/or minimizing blood loss during a procedure. Upon completion of the procedure, the devices and introducer sheath may be removed, leaving a puncture site in the vessel wall. External pressure may be applied to the puncture site until clotting and wound sealing occur. This procedure, however, may be time consuming and expensive, requiring as much as an hour of a physician's or nurse's time. It is also uncomfortable for the patient, and requires that the patient remain immobilized in the operating room, catheter lab, or holding area. In addition, a risk of hematoma exists from bleeding before hemostasis occurs. Various apparatus have been suggested for percutaneously sealing a vascular puncture by occluding the puncture site. For example, U.S. Pat. Nos. 5,192,302 and 5,222,974, issued to Kensey et al., describe the use of a biodegradable plug that may be delivered through an introducer sheath into a puncture site. When deployed, the plug may seal the vessel and provide hemostasis. Such devices, however, may be difficult to position properly with respect to the vessel, which may be particularly significant since it is generally undesirable to expose the plug material, e.g., collagen, within the bloodstream, where it may float downstream and risk causing an embolism. Another technique has been suggested that involves percutaneously suturing the puncture site, such as that disclosed in U.S. Pat. No. 5,304,184, issued to Hathaway et al. Percutaneous suturing devices, however, may require significant skill by the user, and may be mechanically complex and expensive to manufacture. Staples and surgical clips have also been suggested for closing wounds or other openings in tissue. For example, U.S. Pat. Nos. 5,007,921 and 5,026,390, issued to Brown, disclose staples that may be used to close a wound or incision. In one embodiment, an “S” shaped staple is disclosed that includes barbs that may be engaged into tissue on either side of the wound. In another embodiment, a ring-shaped staple is disclosed that includes barbs that project from the ring. These staples, however, have a large cross-sectional profile and therefore may not be easy to deliver through a percutaneous site to close an opening in a vessel wall. U.S. Pat. No. 6,033,427, issued to Lee, discloses a method and device for sealing internal puncture sites which, in one embodiment, uses a dual lumen bleed back system in which the distal bleed back ports are axially spaced from each other such that when the obturator is in a certain location, there will be bleed back through one of the lumens, but not through the other. In addition, skin seals have been proposed that may be threaded into an opening in skin. For example, U.S. Pat. No. 5,645,565, issued to Rudd et al., discloses a surgical plug that may be screwed into a puncture to seal the puncture. The surgical plug includes an enlarged cap and a threaded shaft that extends from the cap. During an endoscopic procedure, the plug may be threaded into an opening through skin until the cap engages the surface of the skin. The plug is intended to seal the opening communicating with a body cavity to prevent insufflation fluid from leaking from the cavity. Such plugs, however, may only be used at the surface of the skin, and may not be introduced through tissue, for example, to seal an opening in the wall of a blood vessel or other subcutaneous region. Various methods and means for determining the location of the distal end of a closure device have been proposed, including “bleed back” methodology such as that disclosed in U.S. Pat. No. 4,738,658 issued to Magro et al. However, prior bleed back devices have been constructed such that blood flow out of the patient continues for a longer period of time during deployment of the sealing means than would be desirable. A further development in bleed back technology is disclosed in published U.S. Patent Application 2004/0019330, in which a control element having an enlarged distal end is used both to control blood flow through the blood vessel puncture and to provide an indication of the position of the distal end of an introducer sheath by withdrawing the enlarged distal end from the lumen of the blood vessel into the puncture in the wall of the blood vessel such that bleed back is, according to this published application, stopped. Leschinsky U.S. Pat. No. 5,871,501 discloses the use of an anchor on a guide wire to provide an indication of the location of the wall of a blood vessel to assist in the placement of a hemostatic material to block flow of blood out of a puncture in the vessel. Although these and other methods and devices have been proposed for deploying a plug to prevent blood flow from a puncture in a blood vessel, a need remains for a safe and effective device and method for deploying a plug for this purpose, and for plugs that are more easily deployed and that provide improved prevention of blood flow. | <SOH> SUMMARY OF INVENTION <EOH>The present invention is directed to improved vascular sealing devices used to seal incisions and/or punctured blood vessels, and to methods of using the devices as well. The vascular sealing devices are particularly useful for sealing incisions and punctures that result from catheterization or interventional procedures, such as angioplasty or stenting, although they are not limited to such uses. These incisions and punctures are commonly made to the femoral artery, and the devices described herein are particularly adapted for these purposes. It should be understood, however, that the devices may also be used to seal incisions and/or punctures in other blood vessels or organs. In several of the preferred embodiments, the sealing device includes a sealing member and a tether. The sealing member generally performs the function of occupying a space in an incision, puncture, or other wound and sealing the space in the incision, puncture, or wound that it occupies, to prevent further blood flow. The tether is typically attached in some manner to the sealing member, and provides the user with the ability to withdraw the sealing member if necessary. In certain embodiments, the tether also provides the user with the ability to manipulate the sealing member for desired effect, such as to radially expand the sealing member within the incision. In a particularly preferred form, the sealing device further includes a restraining member associated with the sealing member. The restraining member provides the ability to more securely restrain the sealing member to prevent it from migrating from the deployment location within a tissue tract. The restraining member may also provide an additional capability of manipulating the sealing member after deployment. In several preferred embodiments, it is desirable to have the sealing member material expand when the sealing member is deployed and exposed to blood flow from the target vessel. This expansion may cause the sealing member, and therefore the sealing device, to expand radially upon deployment and to thereby engage the incision tissue more firmly, thus tending to prevent migration of the sealing device and increase the effectiveness of the seal. The sealing device may take any of a variety of different forms or shapes depending upon the nature of the intended use, the material used to make up the device, and other factors. For example, the sealing device may take the form of an undefined mass in situations where the size and/or shape of the sealing device is not a priority or where the sealing portion of the device is restrained by a restraining portion. In another example, the sealing device takes the form of a disc that is adapted to occupy an incision or puncture wound. Other examples include multiple-disc sealing members, and a pair of discs serving as endcaps to a separate tube shaped member. Still further examples include a solid or rolled tube and a mechanical flower. Other and further shapes and sizes are possible, as is any combinations of these shapes and sizes. Preferably, the tether is attached to the sealing member and is adapted to extend proximally from the sealing member, through and out of the incision, thereby allowing for manipulation by the user. The tether may be used to adjust the sealing member after its deployment, such as by increasing the effective radial dimension of the sealing member, or to remove the sealing member altogether if necessary. In several preferred embodiments, the sealing device has a composite structure that includes one or more sealing members, as described above, and one or more restraining members. Preferably, the restraining member provides the ability to more easily deliver a sealing member and the ability to reduce the likelihood that the sealing member will migrate after its deployment. In a particular preferred form, the restraining member comprises a braided “sock” that encloses the sealing member and allows the sealing member to be more easily delivered to an incision tract. In several preferred embodiments, the sealing member, restraining member, and the tether of the vascular sealing device are preferably formed of bioabsorbable materials such as collagen, polyglycolic acids (PGAs), polylactides (PLAs), hydrogel, or gel-foam. These materials may be provided in solid, gel, foam, felt, or other forms. Of these, hydrogels, such as hydroxypropyl cellulose (HPC) hydrogels, are particularly preferred to be used to make the sealing member due to several of their physical properties. In particular, hydrogels are highly absorbent and exhibit high mechanical strength after absorbing a large amount of liquid. In several alternative embodiments, the sealing device has a composite structure that includes one or more sealing members, as described above, and one or more restraining members. In the alternative embodiments, either the sealing member or the restraining member is formed of a non-bioabsorbable material, while the other member is formed of a bioabsorbable material. Thus, in the alternative embodiments, a bioabsorbable sealing member may be associated with a non-bioabsorbable restraining member, or a non-bioabsorbable sealing member may be associated with a bioabsorbable restraining member. Examples of non-bioabsorbable materials suitable for use in the sealing member or restraining member include nylon, stainless steel, ceramic materials, titanium, gold, platinum, nickel, nickel-titanium alloys, other metals and metal alloys, and other conventional materials suitable for medical use. For example, the restraining member may be formed of a nylon mesh, or of a mesh or braids of stainless steel filaments. The vascular sealing devices described herein may be deployed by any suitable mechanism. One such mechanism particularly adapted for deploying such devices in an incision created by a catheterization or interventional procedure is described in co-pending U.S. patent application Ser. No. 10/850,795, entitled “Locator and Delivery Device and Method of Use,” filed on May 21, 2004, and assigned to Ensure Medical, Inc., the assignee herein. The foregoing application is hereby incorporated by reference in its entirety as if fully set forth herein. The descriptions herein are particularly directed to sealing puncture wounds created during catheterization or interventional procedures, particularly to such wounds in the femoral artery, but it is to be understood that the vascular sealing devices of the present invention can be used to seal other blood vessels and puncture wounds in them. With that understanding, we turn to a more detailed description of the preferred embodiments. | 20050119 | 20111227 | 20051201 | 98119.0 | 0 | WOO, JULIAN W | VASCULAR PLUG HAVING COMPOSITE CONSTRUCTION | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,039,088 | ACCEPTED | Maintenance of metallization baths | A method for the regeneration of an electrolyte bath used for an electroless metallization process. A partial flow of electrolyte is removed from the process vessel and regenerated by dialysis or electrodialysis. Metallization components are replenished. The partial flow is returned to the process vessel. | 1. A method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising: a) removing at least a partial flow of the electrolyte from the process vessel; b) regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis; c) adding metallization components to the at least partial flow; and d) returning the at least partial flow to the process vessel; whereby anions released during the metallization process are exchanged via an ion-selective membrane during said regeneration; and whereby as a counter-solution for the regeneration, a solution is used which is selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution. 2. The method according to claim 1 wherein the anions released in the metallization process are exchanged for hydroxide ions. 3. The method according to claim 1 wherein the operation selected from the group consisting of dialysis and electrodialysis employs an anion-selective membrane. 4. The method according to claim 2 wherein the operation selected from the group consisting of dialysis and electrodialysis employs an anion-selective membrane. 5. The method according to claim 1 wherein the metallization process is for deposition of at least one metal selected from the group consisting of copper, nickel, a ternary nickel alloy, or gold. 6. The method according to claim 4 wherein the metallization process is for deposition of at least one metal selected from the group consisting of copper, nickel, a ternary nickel alloy, or gold. 7. The method of claim 1 wherein the operation selected from the group consisting of dialysis and electrodialysis involves exchange of at least one ion from the group consisting of sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, and chloride ions. 8. The method of claim 6 wherein the operation selected from the group consisting of dialysis and electrodialysis involves exchange of at least one ion from the group consisting of sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, and chloride ions. 9. The method according to claim 1 wherein the counter solution is conducted in a counter-flow with respect to the partial flow of electrolyte. 10. The method according to claim 1 wherein the counter solution is conducted in parallel with respect to the partial flow of electrolyte. 11. The method of claim 1 further comprising regenerating the counter-solution after the operation selected from the group consisting of dialysis and electrodialysis. 12. The method according to claim 11 wherein at least one oxidation agent selected from the group consisting of hydrogen peroxide, peroxide sulfates, or Caroat is used in regenerating the counter-solution. 13. The method of claim 1 further comprising precipitating the anions received in the counter-solution as hard-to-dissolve salts to regenerate the counter-solution after the operation selected from the group consisting of dialysis and electrodialysis. 14. The method of claim 13 wherein at least one substance selected from the group consisting of barium hydroxide and calcium hydroxide is used for said precipitation. 15. A method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising: a) removing at least a partial flow of the electrolyte from the process vessel; b) regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of anions selected from the group consisting of sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, and chloride ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; c) replenishing to the at least partial flow a metallic source for deposition of a metal selected from the group consisting of copper, nickel, a ternary nickel alloy, and gold; d) replenishing to the at least partial flow a reducing agent; and e) returning the at least partial flow to the process vessel. 16. The method of claim 15 further comprising regenerating the counter-solution by oxidation after the operation selected from the group consisting of dialysis and electrodialysis. 17. The method of claim 15 further comprising precipitating the anions received in the counter-solution as hard-to-dissolve salts to regenerate the counter-solution after the operation selected from the group consisting of dialysis and electrodialysis. 18. The method of claim 17 wherein at least one substance selected from the group consisting of barium hydroxide and calcium hydroxide is used for said precipitation. 19. A method for the regeneration of an electrolyte bath used for an electroless copper metallization process in a process vessel comprising: a) removing at least a partial flow of the electrolyte from the process vessel; b) regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of sulfate ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; c) replenishing copper sulfate to the at least partial flow as a metallic source for deposition of a copper; d) replenishing a reducing agent to the at least partial flow; and e) returning the at least partial flow to the process vessel. 20. The process of claim 19 wherein the reducing agent comprises forhaldehyde. | FIELD OF THE INVENTION The invention under consideration concerns a method for the maintenance of metallization baths in electroplating and electroforming technology. In particular, the invention concerns a method for the maintenance of metallization baths in the deposition of metals without a current. BACKGROUND OF THE INVENTION In the deposition of metals without an outside current, such as in the chemical deposition of copper from corresponding electrolytes without an outside current, a reducing agent is added to the electrolyte, which agent as an interior voltage source makes possible the deposition of the metal. The basic principle of metal deposition without an outside current will be explained here with the example of a copper electrolyte. As a rule, electrolytes for chemical copper deposition without an outside current contain complex- or chelate-bound copper ions, such as copper tartrate complexes or copper-EDTA chelates. Formaldehyde or a comparable reducing agent, which, as the result of an oxidation reaction to the formate or to the corresponding anion, provides the electrons needed for the reduction of the copper, is used, as a rule, as the reducing agent. Formaldehyde, however, is able to act as a sufficiently strong reducing agent on divalent copper ions, as they are used, as a rule, in electrolytes for the deposition of copper without an outside current, and to make possible a metal deposition, only in a highly alkaline pH range such as between about pH 11 and about pH 14. From this, it follows that the copper ions present in the electrolyte are so strongly complexed or chelated that they cannot form hard-to-dissolve metal hydroxides. Moreover, copper is introduced into the electrolyte, as a rule, in the form of sulfates. As a consequence of the reaction of divalent copper ions to elementary copper, the electrolyte is enriched with sulfate anions. This sulfate anions enrichment, produced by the oxidation of the formaldehyde in combination with the concentration increase of formate anions, leads to a lowering of the pH value. In order to continue to hold the electrolyte in a workable pH range, alkali hydroxides, such as sodium hydroxide, are added. Moreover, the consumed quantities of copper sulfate and formaldehyde are subsequently metered to the electrolyte. As a result of the foregoing, the chemical and physical characteristics of the electrolyte therefore change, which leads to a limited durability and applicability of the electrolyte. Nickel baths without a current work mostly in an acidic pH range. There, bath maintenance by means of electrodialysis is already known from documents EP 1 239 057 A1, DE 198 49 278 C1, and EP 0 787 829 A1. The process described there and the combination of methods and membranes cannot be used, however, for copper without a current, or for others in alkaline metallization baths working without a current. SUMMARY OF THE INVENTION Thus, a goal of the invention is to make available a method which is able to overcome the aforementioned disadvantages and guarantee a longer electrolyte use and operability for the deposition of metals without a current. This goal is attained, in accordance with the invention, by a method for the regeneration of electrolyte baths for metallization without a current by means of the following method steps: a) carrying off at least a partial flow of the electrolyte from the process vessel; b) regeneration of the carried-off electrolyte flow; c) addition of components used in the metallization process; d) return of regenerated electrolyte flow to the process vessel; characterized in that for the regeneration, the carried-off partial flow is supplied to a dialysis and/or electrodialysis unit, in which the anions released during the metallization process without a current are exchanged via an ion-selective membrane. In an advantageous manner, the anions released in the metallization process are exchanged for hydroxide ions in the dialysis and/or electrodialysis unit in the method of the invention. For this purpose, the dialysis and/or electrodialysis unit in the method of the invention advantageously has an anion-selective membrane. As a counter-solution to the dialysis and/or electrodialysis of the electrolyte, alkali hydroxide-containing and/or alkaline earth hydroxide-containing solutions can be used in the method of the invention. Such an invention is suitable for electrolytes for the deposition of copper, nickel, ternary nickel alloys, and gold, without a current. The ions to be exchanged by means of dialysis and/or electrodialysis can be sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, chloride ions, and other anions which dissolve well. Briefly, therefore, the invention is directed to a method for the regeneration of alkali, cyanide-free, zinc- and nickel-containing electrolyte baths for metallization without a current. The method of the invention has the following steps: the carrying-off of at least a partial flow of the electrolyte from the process vessel into a regeneration unit, the return of the regenerated electrolyte flow to the process vessel, wherein the regeneration unit has a dialysis and/or electrodialysis unit with an anion-selective membrane and in which the anions formed during the process of the metallization without a current are exchanged for hydroxide ions. The electrolyte current thus regenerated can be supplemented by the consumed components. In another aspect, the invention is a method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis; c) adding metallization components to the at least partial flow; and d) returning the at least partial flow to the process vessel. The anions released during the metallization process are exchanged via an ion-selective membrane during said regeneration; and as a counter-solution for the regeneration, a solution is used which is selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution. The invention is also directed to a method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of anions selected from the group consisting of sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, and chloride ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; replenishing to the at least partial flow a metallic source for deposition of a metal selected from the group consisting of copper, nickel, a ternary nickel alloy, and gold; d) replenishing to the at least partial flow a reducing agent; and e) returning the at least partial flow to the process vessel. In a further aspect the invention is directed to a method for the regeneration of an electrolyte bath used for an electroless copper metallization process in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of sulfate ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; replenishing copper sulfate to the at least partial flow as a metallic source for deposition of a copper; replenishing a reducing agent to the at least partial flow; and returning the at least partial flow to the process vessel. In another refinement of the method of the invention, the alkali hydroxide-containing and/or alkaline earth hydroxide-containing solutions, used as a counter-solution in the dialysis and/or electrodialysis and/or electrodialysis process, are regenerated according to the dialysis process. This can occur, according to the invention, by suitable oxidation agents. Following such a regeneration, the alkali and/or alkaline-earth solutions can optionally be concentrated. Another possibility for regenerating the used alkali and/or alkaline earth solutions in the method of the invention is the precipitation of the anions received in the dialysis and/or electrodialysis process as hard-to-dissolve salts. Such a salt can be, for example, the hard-to-dissolve barium sulfate, in the case of sulfate ions, which can be precipitated by the addition of barium hydroxide to the alkali hydroxide-containing and/or alkaline earth hydroxide-containing counter-solutions of the dialysis and/or electrodialysis processes to be regenerated. Other suitable salts are, for example, calcium hydroxide or, in general, other substances forming hard-to-dissolve compounds with sulfates. Formate ions can be reacted in CO2 and water by oxidation agents suitable for the regeneration of the counter-solutions. Suitable oxidation agents for such a reaction are hydrogen peroxide, peroxide sulfates or the product known as Caroat from the Degussa Company. Prerequisite for the use of a dialysis and/or electrodialysis method for the regeneration of electrolytes for the deposition of metals without an outside current, is the use of anion-selective membranes in the dialysis and/or electrodialysis steps. Suitable anion-selective membranes for a method in accordance with the invention are, for example, commercial mono- and bivalent anion-exchanger membranes from Tokuyama Soda Co. Ltd., Asaki Glass Co. Ltd., Purolite International, Polymerchemie Altmeier, or Reichelt Chemietechnik. The application of an electric field in the dialysis step of the method of the invention advantageously accelerates the deposition process. In principle, the electrolyte to be regenerated and the alkali- and/or alkaline earth-containing counter-solution can be conducted in a parallel flow, as well as in a counter-flow, both when using a dialysis stage and also when using an electrodialysis stage. BRIEF DESCRIPTION OF THE FIGURES FIGS. 1 and 2 are schematic illustrations of variations of the invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS This application claims priority from German application 10 2004 002 778.1, the entire disclosure of which is expressly incorporated herein by reference. FIG. 1 shows a conventional method for the metallization of substrates without a current. In the case of a copper deposition without a current on a substrate (3) to obtain a metallized substrate (7), a partial flow (5) is removed from the electrolyte (4), which partial flow is enriched with, for example, copper sulfate (1) and formaldehyde (2), as a function of the consumed quantity of metal ions and reducing agent, and is again supplied to the electrolyte (4). The electrolyte (4) is enriched, in the course of the method, with formate and sulfate ions (6). FIG. 2 shows the method of the invention for the regeneration of electrolytes for the deposition of metals without a current. A partial flow is removed from the electrolyte (4), for example, via a pump (8), and supplied to a dialysis and/or electrodialysis unit (11). The dialysis and/or electrodialysis unit has anion-selective membranes (19). The counter-solution for the dialysis/electrodialysis (9) is also supplied to the dialysis and/or electrodialysis unit (11), for example, via a pump (8). This can occur in a parallel flow or also in a counter-flow to the electrolyte (4) to be regenerated. The branched-off electrolyte partial flow (5) is enriched again with metal ions and reducing agents, following the regeneration in the dialysis and/or electrodialysis unit (11). These can be, for example, copper sulfate (1) and formaldehyde (2). In the case of copper sulfate and formaldehyde, formate and sulfate ions are received by the counter-solution (9) in the dialysis and/or electrolysis unit (11) via the anion-selective membrane (19). For the regeneration of the counter-solution, precipitation agents (12), such as barium hydroxide, can then be added to it for sulfate precipitation (13). The precipitated sulfates (14) can be separated. The formate ions received in the counter-solution can be reacted by the addition of oxidation agents (15) in an oxidation (16) to carbon dioxide (17) and water. The regenerated counter-solution (18) can be returned, with the addition of alkali and/or alkaline earth hydroxides (10). Reference Symbol List 1 Addition of copper sulfate 2 Addition of formaldehyde 3 Substrate to be metallized 4 Electrolyte for copper deposition without a current 5 Partial flow 6 Enrichment in formate and sulfate ions 7 Metallized substrate 8 Pump 9 Counter-solution for the dialysis/electrodialysis 10 Alkali-/Alkaline earth hydroxide addition 11 Dialysis/Electrodialysis unit 12 Addition of precipitation agent 13 Sulfate precipitation 14 Precipitated sulfates 15 Addition of oxidation agents 16 Oxidation of formate ions 17 Carbon dioxide 18 Return regenerated counter-solution 19 Anion-selective membrane When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. As various changes could be made in the above methods and products without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in any accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | <SOH> BACKGROUND OF THE INVENTION <EOH>In the deposition of metals without an outside current, such as in the chemical deposition of copper from corresponding electrolytes without an outside current, a reducing agent is added to the electrolyte, which agent as an interior voltage source makes possible the deposition of the metal. The basic principle of metal deposition without an outside current will be explained here with the example of a copper electrolyte. As a rule, electrolytes for chemical copper deposition without an outside current contain complex- or chelate-bound copper ions, such as copper tartrate complexes or copper-EDTA chelates. Formaldehyde or a comparable reducing agent, which, as the result of an oxidation reaction to the formate or to the corresponding anion, provides the electrons needed for the reduction of the copper, is used, as a rule, as the reducing agent. Formaldehyde, however, is able to act as a sufficiently strong reducing agent on divalent copper ions, as they are used, as a rule, in electrolytes for the deposition of copper without an outside current, and to make possible a metal deposition, only in a highly alkaline pH range such as between about pH 11 and about pH 14. From this, it follows that the copper ions present in the electrolyte are so strongly complexed or chelated that they cannot form hard-to-dissolve metal hydroxides. Moreover, copper is introduced into the electrolyte, as a rule, in the form of sulfates. As a consequence of the reaction of divalent copper ions to elementary copper, the electrolyte is enriched with sulfate anions. This sulfate anions enrichment, produced by the oxidation of the formaldehyde in combination with the concentration increase of formate anions, leads to a lowering of the pH value. In order to continue to hold the electrolyte in a workable pH range, alkali hydroxides, such as sodium hydroxide, are added. Moreover, the consumed quantities of copper sulfate and formaldehyde are subsequently metered to the electrolyte. As a result of the foregoing, the chemical and physical characteristics of the electrolyte therefore change, which leads to a limited durability and applicability of the electrolyte. Nickel baths without a current work mostly in an acidic pH range. There, bath maintenance by means of electrodialysis is already known from documents EP 1 239 057 A1, DE 198 49 278 C1, and EP 0 787 829 A1. The process described there and the combination of methods and membranes cannot be used, however, for copper without a current, or for others in alkaline metallization baths working without a current. | <SOH> SUMMARY OF THE INVENTION <EOH>Thus, a goal of the invention is to make available a method which is able to overcome the aforementioned disadvantages and guarantee a longer electrolyte use and operability for the deposition of metals without a current. This goal is attained, in accordance with the invention, by a method for the regeneration of electrolyte baths for metallization without a current by means of the following method steps: a) carrying off at least a partial flow of the electrolyte from the process vessel; b) regeneration of the carried-off electrolyte flow; c) addition of components used in the metallization process; d) return of regenerated electrolyte flow to the process vessel; characterized in that for the regeneration, the carried-off partial flow is supplied to a dialysis and/or electrodialysis unit, in which the anions released during the metallization process without a current are exchanged via an ion-selective membrane. In an advantageous manner, the anions released in the metallization process are exchanged for hydroxide ions in the dialysis and/or electrodialysis unit in the method of the invention. For this purpose, the dialysis and/or electrodialysis unit in the method of the invention advantageously has an anion-selective membrane. As a counter-solution to the dialysis and/or electrodialysis of the electrolyte, alkali hydroxide-containing and/or alkaline earth hydroxide-containing solutions can be used in the method of the invention. Such an invention is suitable for electrolytes for the deposition of copper, nickel, ternary nickel alloys, and gold, without a current. The ions to be exchanged by means of dialysis and/or electrodialysis can be sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, chloride ions, and other anions which dissolve well. Briefly, therefore, the invention is directed to a method for the regeneration of alkali, cyanide-free, zinc- and nickel-containing electrolyte baths for metallization without a current. The method of the invention has the following steps: the carrying-off of at least a partial flow of the electrolyte from the process vessel into a regeneration unit, the return of the regenerated electrolyte flow to the process vessel, wherein the regeneration unit has a dialysis and/or electrodialysis unit with an anion-selective membrane and in which the anions formed during the process of the metallization without a current are exchanged for hydroxide ions. The electrolyte current thus regenerated can be supplemented by the consumed components. In another aspect, the invention is a method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis; c) adding metallization components to the at least partial flow; and d) returning the at least partial flow to the process vessel. The anions released during the metallization process are exchanged via an ion-selective membrane during said regeneration; and as a counter-solution for the regeneration, a solution is used which is selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution. The invention is also directed to a method for the regeneration of an electrolyte bath used for a metallization process without a current in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of anions selected from the group consisting of sulfate ions, formate ions, hypophosphite ions, phosphite ions, phosphate ions, and chloride ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; replenishing to the at least partial flow a metallic source for deposition of a metal selected from the group consisting of copper, nickel, a ternary nickel alloy, and gold; d) replenishing to the at least partial flow a reducing agent; and e) returning the at least partial flow to the process vessel. In a further aspect the invention is directed to a method for the regeneration of an electrolyte bath used for an electroless copper metallization process in a process vessel comprising removing at least a partial flow of the electrolyte from the process vessel; regenerating said at least partial flow removed in step (a) via an operation selected from the group consisting of dialysis and electrodialysis involving exchange of sulfate ions released during the metallization process for hydroxide ions via an anion-selective membrane and a counter-solution selected from the group consisting of an alkali hydroxide-containing solution and an alkaline earth hydroxide-containing solution; replenishing copper sulfate to the at least partial flow as a metallic source for deposition of a copper; replenishing a reducing agent to the at least partial flow; and returning the at least partial flow to the process vessel. In another refinement of the method of the invention, the alkali hydroxide-containing and/or alkaline earth hydroxide-containing solutions, used as a counter-solution in the dialysis and/or electrodialysis and/or electrodialysis process, are regenerated according to the dialysis process. This can occur, according to the invention, by suitable oxidation agents. Following such a regeneration, the alkali and/or alkaline-earth solutions can optionally be concentrated. Another possibility for regenerating the used alkali and/or alkaline earth solutions in the method of the invention is the precipitation of the anions received in the dialysis and/or electrodialysis process as hard-to-dissolve salts. Such a salt can be, for example, the hard-to-dissolve barium sulfate, in the case of sulfate ions, which can be precipitated by the addition of barium hydroxide to the alkali hydroxide-containing and/or alkaline earth hydroxide-containing counter-solutions of the dialysis and/or electrodialysis processes to be regenerated. Other suitable salts are, for example, calcium hydroxide or, in general, other substances forming hard-to-dissolve compounds with sulfates. Formate ions can be reacted in CO 2 and water by oxidation agents suitable for the regeneration of the counter-solutions. Suitable oxidation agents for such a reaction are hydrogen peroxide, peroxide sulfates or the product known as Caroat from the Degussa Company. Prerequisite for the use of a dialysis and/or electrodialysis method for the regeneration of electrolytes for the deposition of metals without an outside current, is the use of anion-selective membranes in the dialysis and/or electrodialysis steps. Suitable anion-selective membranes for a method in accordance with the invention are, for example, commercial mono- and bivalent anion-exchanger membranes from Tokuyama Soda Co. Ltd., Asaki Glass Co. Ltd., Purolite International, Polymerchemie Altmeier, or Reichelt Chemietechnik. The application of an electric field in the dialysis step of the method of the invention advantageously accelerates the deposition process. In principle, the electrolyte to be regenerated and the alkali- and/or alkaline earth-containing counter-solution can be conducted in a parallel flow, as well as in a counter-flow, both when using a dialysis stage and also when using an electrodialysis stage. | 20050119 | 20111115 | 20050908 | 75111.0 | 0 | PHASGE, ARUN S | MAINTENANCE OF METALLIZATION BATHS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,039,129 | ACCEPTED | Vehicular information and monitoring system and methods | Information management and monitoring system for a vehicle including a vehicle monitoring system including a plurality of sensors for monitoring vehicular components, a diagnostic module arranged on the vehicle and coupled to the vehicle monitoring system to receive and process data about the components therefrom, and a remote service center capable of servicing the components. A communication system, e.g., a cellular telephone capable of voice communications, is arranged on the vehicle and coupled to the diagnostic module to enable communications of data from the diagnostic module to the remote service center such that the remote service center receives data about the vehicular components. The remote service center can be situated at a dealer which can have its personnel contact the driver, e.g., via the telephone, to schedule service of the vehicle, the service being determined based on the communicated data from the diagnostic module on the vehicle. | 1. An information management and monitoring system for a vehicle, comprising: a vehicle monitoring system including a plurality of sensors for monitoring components of the vehicle; a diagnostic module arranged on the vehicle, said diagnostic module being coupled to said vehicle monitoring system and arranged to receive and process data about the monitored components from said vehicle monitoring system; a remote service center capable of servicing the vehicle components; and a communication system arranged on the vehicle and coupled to said diagnostic module for enabling communications of data from said diagnostic module to said remote service center such that said remote service center receives data about the monitored components of the vehicle. 2. The system of claim 1, wherein said communication system is a cellular telephone capable of voice communications. 3. The system of claim 1, further comprising a user interactive device coupled to and controlled by said diagnostic module, said user interactive device being a display on which messages relating to the monitored components are provided to the user. 4. The system of claim 1, wherein said diagnostic module is arranged to derive diagnostic data from data about the monitored components provided by said sensors of said vehicle monitoring system. 5. The system of claim 4, wherein the data derived by said diagnostic module from data about the monitored components provided by said sensors of said vehicle monitoring system is an indication of a potential failure of one of the components of the vehicle. 6. The system of claim 1, further comprising a vehicle bus for coupling said diagnostic module, said vehicle monitoring system and said communication system. 7. The system of claim 1, wherein said communication system is arranged to communicate with said remote service center via a satellite. 8. A method for information management and monitoring of a vehicle, comprising: arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle; arranging a diagnostic module on the vehicle; directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby; coupling a communication system on the vehicle to the diagnostic module; and establishing communications between the diagnostic module and a remote service center capable of servicing the monitored components to enable transmission of data between the diagnostic module and the remote service center such that the remote service center receives data about the monitored components of the vehicle. 9. The method of claim 8, wherein the communication system is a cellular telephone capable of voice communications. 10. The method of claim 8, further comprising: coupling a display to the diagnostic module; and causing the display of messages to the driver to notify the driver of the status of the monitored components as determined by the diagnostic system. 11. The method of claim 8, further comprising deriving diagnostic data in the diagnostic module from the data about the monitored components provided by the vehicle monitoring system, the derived data being transmitted to the remote service center. 12. The method of claim 11, wherein the data derived from the data about the monitored components provided by the vehicle monitoring system is an indication of a potential failure of one of the components of the vehicle. 13. The method of claim 8, further comprising coupling the diagnostic module, the vehicle monitoring system and the communication system via a vehicle bus. 14. The method of claim 8, further comprising contacting the vehicle owner from the remote service center to schedule repair or maintenance of the vehicle upon receiving data from the diagnostic module at the remote service center. 15. A method for scheduling servicing of a vehicle, comprising: arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle; arranging a diagnostic module on the vehicle; directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby; coupling a communication system on the vehicle to the diagnostic module; establishing communications between the diagnostic module and a dealer capable of servicing the monitored components to enable transmission of data between the diagnostic module and the dealer such that the dealer receives data about the monitored components of the vehicle; and upon receiving data from the diagnostic module at the dealer, contacting the vehicle owner to schedule repair or maintenance of the vehicle. 16. The method of claim 15, wherein the communication system is a cellular telephone capable of voice communications. 17. The method of claim 15, further comprising: coupling a display to the diagnostic module; and causing the display of messages to the driver to notify the driver of the status of the components as determined by the diagnostic system. 18. The method of claim 15, further comprising deriving diagnostic data in the diagnostic module from the data about the monitored components provided by the vehicle monitoring system, the derived data being transmitted to the dealer. 19. The method of claim 18, wherein the data derived from the data about the monitored components provided by the vehicle monitoring system is an indication of a potential failure of one of the components of the vehicle. 20. The system of claim 15, further comprising coupling the diagnostic module, the vehicle monitoring system and the communication system via a vehicle bus. 21. A method for information management and monitoring of a plurality of vehicles, comprising: arranging a vehicle monitoring system including a plurality of sensors on each vehicle to monitor components of the vehicle; arranging a diagnostic module on each vehicle; directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby; coupling a communication system on each vehicle to the diagnostic module; establishing communications between the diagnostic module and a data gathering facility which accumulates information about the failure rate of the components to enable transmission of data between the diagnostic module and the data gathering facility such that the data gathering facility receives data about the monitored components of the vehicle; and accumulating date from the vehicle at the data gathering facility to enable calculation of statistics about failure rate of the components. 22. The method of claim 21, wherein the communication system is a cellular telephone capable of voice communications. 23. The method of claim 21, further comprising deriving diagnostic data in the diagnostic module from the data about the monitored components provided by the vehicle monitoring system, the derived data being transmitted to the data gathering facility. 24. The method of claim 23, wherein the data derived from the data about the monitored components provided by the vehicle monitoring system is an indication of a potential failure of one of the components of the vehicle. | CROSS REFERENCE TO RELATED APPLICATIONS This application is a divisional of U.S. patent application Ser. No. 10/701,361, filed Nov. 4, 2003 which is: 1) a continuation-in-part of U.S. patent application Ser. No. 10/188,673 filed Jul. 3, 2002, now U.S. Pat. No. 6,738,697, which is a continuation-in-part of U.S. patent application Ser. No. 09/753,186 filed Jan. 2, 2001, now U.S. Pat. No. 6,484,080, which is a continuation-in-part of U.S. patent application Ser. No. 09/137,918 filed Aug. 20, 1998, now U.S. Pat. No. 6,175,787, which is a continuation-in-part of U.S. patent application Ser. No. 08/476,077 filed Jun. 7, 1995, now U.S. Pat. No. 5,809,437; and 2) a continuation-in-part of U.S. patent application Ser. No. 10/174,709 filed Jun. 19, 2002, now U.S. Pat. No. 6,733,506; 3) a continuation-in-part of U.S. patent application Ser. No. 10/330,938 filed Dec. 27, 2002, now U.S. Pat. No. 6,823,244; 4) a continuation-in-part of U.S. patent application Ser. No. 10/613,453 filed Jul. 3, 2003; 5) a continuation-in-part 0f U.S. patent application Ser. No. 09/925,062 filed Aug. 8, 2001, now U.S. Pat. No. 6,733,036, which is a continuation-in-part of U.S. patent application Ser. No. 09/767,020 filed Jan. 23, 2001, now U.S. Pat. No. 6,533,316, which is a continuation-in-part of U.S. patent application Ser. No. 09/356,314 filed Jul. 16, 1999, now U.S. Pat. No. 6,326,704, which is A) a continuation-in-part of U.S. patent application Ser. No. 08/947,661 filed Oct. 9, 1997, now abandoned, which claims priority under 35 U.S.C. §119(e) of U.S. provisional patent application Ser. No. 60/028,046, filed Oct. 9, 1996; and B) a continuation-in-part of U.S. patent application Ser. No. 09/137,918 filed Aug. 20, 1998, now U.S. Pat. No. 6,175,787 which is a continuation-in-part of U.S. patent application Ser. No. 08/476,077 filed Jun. 7, 1995, now U.S. Pat. No. 5,809,437; and 6) a continuation-in-part of U.S. patent application Ser. No. 10/638,743 filed Aug. 11, 2003. All of the references, patents and patent applications that are referred to above are incorporated by reference in their entirety as if they had each been set forth herein in full. FIELD OF THE INVENTION The present invention relates to methods and apparatus for obtaining and transmitting data relating to the components in a vehicle and other information relating to the operating conditions of the vehicle to one or more remote locations distant from the vehicle, e.g., via a telematics link. The present invention also relates to systems and method for diagnosing the state or condition of a vehicle, e.g., whether the vehicle is about to rollover or is experiencing a crash and whether the vehicle has a component which is operating abnormally and could possibly fail resulting in a crash or severe handicap for the operator, and transmitting data relating to the diagnosis of the components in the vehicle and optionally other information relating to the operating conditions of the vehicle to one or more remote locations, i.e., via a telematics link. The present invention further relates to methods and apparatus for diagnosing components in a vehicle and determining the status of occupants in a vehicle and transmitting data relating to the diagnosis of the components in the vehicle, and optionally other information relating to the operating conditions of the vehicle, and data relating to the occupants to one or more remote facilities such as a repair facility and an emergency response station. BACKGROUND OF THE INVENTION Set below is some relevant background relating to the invention. Additional background is found in the parent application, U.S. patent application Ser. No. 10/701,361, and is incorporated by reference herein. 1. Diagnostics 1.1 General Diagnostics When a vehicle component begins to fail, the repair cost is frequently minimal if the impending failure of the component is caught early, but increases as the repair is delayed. Sometimes, if a component in need of repair is not caught in a timely manner, the component, and particularly the impending failure thereof, can cause other components of the vehicle to deteriorate. One example is where the water pump fails gradually until the vehicle overheats and blows a head gasket. Another example is when a tire gradually loses air until it heats up, fails and causes an accident. It is desirable, therefore, to determine that a vehicle component is about to fail as early as possible so as to minimize the probability of a breakdown and the resulting repair costs. There are various gages on an automobile which alert the driver to various vehicle problems. For example, if the oil pressure drops below some predetermined level, the driver is warned to stop his vehicle immediately. Similarly, if the coolant temperature exceeds some predetermined value, the driver is also warned to take immediate corrective action. In these cases, the warning often comes too late as most vehicle gages alert the driver after he or she can conveniently solve the problem. Thus, what is needed is a component failure warning system that alerts the driver to the impending failure of a component sufficiently in advance of the time when the problem gets to a catastrophic point. Some astute drivers can sense changes in the performance of their vehicle and correctly diagnose that a problem with a component is about to occur. Other drivers can sense that their vehicle is performing differently but they don't know why or when a component will fail or how serious that failure will be, or possibly even what specific component is the cause of the difference in performance. The invention disclosed herein will, in most cases, solve this problem by predicting component failures in time to permit maintenance and thus prevent vehicle breakdowns. Presently, automobile sensors in use are based on specific predetermined or set levels, such as the coolant temperature or oil pressure, whereby an increase above the set level or a decrease below the set level will activate the sensor, rather than being based on changes in this level over time. The rate at which coolant heats up, for example, can be an important clue that some component in the cooling system is about to fail. There are no systems currently on automobiles to monitor the numerous vehicle components over time and to compare component performance with normal performance. Nowhere in the vehicle is the vibration signal of a normally operating front wheel stored, for example, or for that matter, any normal signal from any other vehicle component. Additionally, there is no system currently existing on a vehicle to look for erratic behavior of a vehicle component and to warn the driver or the dealer that a component is misbehaving and is therefore likely to fail in the very near future. Basically, the operating of an automobile should be a process not a project. A purpose of this invention is to eliminate breakdowns through identifying potential component failures before they occur so that they can be repaired in a timely manner. Another purpose is to notify the operator and a service facility of the pending failure so that it can be prevented. Sometimes, when a component fails, a catastrophic accident results. In the Firestone tire case, for example, over 100 people were killed when a tire of a Ford Explorer blew out which caused the Ford Explorer to rollover. Similarly, other component failures can lead to loss of control of the vehicle and a subsequent accident. It is thus important to accurately forecast that such an event will take place but furthermore, for those cases where the event takes place suddenly without warning, it is also important to diagnose the state of the entire vehicle, which in some cases can lead to automatic corrective action to prevent unstable vehicle motion or rollovers resulting in an accident. Finally, an accurate diagnostic system for the entire vehicle can determine much more accurately the severity of an automobile crash once it has begun by knowing where the accident is taking place on the vehicle (e.g., the part of or location on the vehicle which is being impacted by an object) and what is colliding with the vehicle based on a knowledge of the force deflection characteristics of the vehicle at that location. Therefore, in addition to a component diagnostic, the teachings of this invention also provide a diagnostic system for the entire vehicle prior to and during accidents. In particular, this invention is concerned with the simultaneous monitoring of multiple sensors on the vehicle so that the best possible determination of the state of the vehicle can be determined. Current crash sensors operate independently or at most one sensor may influence the threshold at which another sensor triggers a deployable restraint as taught in the current assignee's U.S. patent application Ser. No. 10/638,743 filed Aug. 11, 2003 and related patents and pending applications. In the teachings of this invention, two or more sensors, frequently accelerometers, are monitored simultaneously and the outputs of these multiple sensors can be combined continuously in making the crash severity analysis. U.S. Pat. No. 5,754,965 (Hagenbuch) describes an apparatus for diagnosing the state of health of a construction vehicle and providing the operator of the vehicle with a substantially real-time indication of the efficiency of the vehicle in performing as assigned task with respect to a predetermined goal. A processor in the vehicle monitors sensors that provide information regarding the state of health of the vehicle and the amount of work the vehicle has done. The processor records information that describes events leading up to the occurrence of an anomaly for later analysis. The sensors are also used to prompt the operator to operate the vehicle at optimum efficiency. The system of this patent does not predict or warn the operator or the home base of a pending problem. Asami et al. (U.S. Pat. No. 4,817,418) is directed to a failure diagnosis system for a vehicle including a failure display means for displaying failure information to a driver. This system only reports failures after they have occurred and does not predict them. Tieman et al. (U.S. Pat. No. 5,313,407) is directed, inter alia, to a system for providing an exhaust active noise control system, i.e., an electronic muffler system, including an input microphone 60 which senses exhaust noise at a first location 61 in an exhaust duct 58. An engine has exhaust manifolds 56,57 feeding exhaust air to the exhaust duct 58. The exhaust noise sensed by the microphone 60 is processed to obtain an output from an output speaker 65 arranged downstream of the input microphone 61 in the exhaust path in order to cancel the noise in the exhaust duct 58. No attempt is made to diagnose system faults nor predict them. Haramaty et al. (U.S. Pat. No. 5,406,502) describes a system that monitors a machine in a factory and notifies maintenance personnel remote from the machine (not the machine operator) that maintenance should be scheduled at a time when the machine is not in use. Haramaty et al. does not expressly relate to vehicular applications. NASA Technical Support Package MFS-26529 “Engine Monitoring Based on Normalized Vibration Spectra”, describes a technique for diagnosing engine health using a neural network based system but does not suggest that this system can or should be used on land vehicles. A paper “Using acoustic emission signals for monitoring of production processes” by H. K. Tonshoff et al. also provides a good description of how acoustic signals can be used to predict the state of machine tools and is incorporated by reference herein in its entirety. Again no suggestion is made that this can be used for diagnosing components of land vehicles. 1.2 Pattern Recognition Marko et al. (U.S. Pat. No. 5,041,976) is directed to a diagnostic system using pattern recognition for electronic automotive control systems and particularly for diagnosing faults in the engine of a motor vehicle after they have occurred. For example, Marko et al. is interested in determining cylinder specific faults after the cylinder is operating abnormally. More specifically, Marko et al. is directed to detecting a fault in a vehicular electromechanical system directly, i.e., by means of the measurement of parameters of sensors which are designed to be affected only by that system, and after that fault has already manifested itself in the system. In order to form the fault detecting system, the parameters from these sensors are input to a pattern recognition system for training thereof. Then, known faults are introduced and the parameters from the sensors are input into the pattern recognition system with an indicia of the known fault. Thus, during subsequent operation, the pattern recognition system can determine the fault of the electromechanical system based on the parameters of the sensors, assuming that the fault was “trained” into the pattern recognition system and has already occurred. When the electromechanical system is an engine, the parameters input into the pattern recognition system for training thereof, and used for fault detection during operation, all relate to the engine. In other words, each parameter will be affected by the operation of the engine and depend thereon and changes in the operation of the engine will alter the parameter, e.g., the manifold absolute pressure is an indication of the airflow into the engine. In this case, the signal from the manifold absolute pressure sensor may be indicative of a fault in the intake of air into the engine, e.g., the engine is drawing in too much or too little air, and is thus affected by the operation of the engine. Similarly, the mass air flow is the airflow into the engine and is an alternative to the manifold absolute pressure. It is thus a parameter that is directly associated with, related to and dependent on the engine. The exhaust gas oxygen sensor is also affected by the operation of the engine, and thus directly associated therewith, since during normal operation, the mixture of the exhaust gas is neither rich or lean whereas during abnormal engine operation, the sensor will detect an abrupt change indicative of the mixture being too rich or too lean. Thus, the system of Marko et al. is based on the measurement of sensors which affect or are affected by, i.e., are directly associated with, the operation of the electromechanical system for which faults are to be detected. However, the system of Marko et al. does not detect faults in the sensors that are conducting the measurements, e.g., a fault in the exhaust gas oxygen sensor, or faults that are only developing but have not yet manifested themselves or faults in other systems. Rather, the sensors are used to detect a fault in the system after it has occurred. Marko does not attempt to forecast or predict that a fault will occur. Aside from the references above of assignee's patents and patent applications and the one example of an engine control system, pattern recognition has not been applied to the diagnosis of any faults on a vehicle. In the referenced examples, the engine controller for example, only sensors directly associated with the component have been used. No attempt has been made to forecast that a failure will occur and no system has been disclosed other than by the assignee for transmitting such diagnostic information to a site off of the vehicle. 2.0 Telematics Every automobile driver fears that his or her vehicle will break down at some unfortunate time, e.g., when he or she is traveling at night, during rush hour, or on a long trip away from home. To help alleviate that fear, certain luxury automobile manufacturers provide roadside service in the event of a breakdown. Nevertheless, unless the vehicle is equipped with OnStar® or an equivalent service, the vehicle driver must still be able to get to a telephone to call for service. It is also a fact that many people purchase a new automobile out of fear of a breakdown with their current vehicle. The inventions described herein are primarily concerned with preventing breakdowns and with minimizing maintenance costs by predicting component failure that would lead to such a breakdown before it occurs. Another important aspect disclosed in the Breed et al. patents relates to the operation of the cellular communications system in conjunction with the vehicle interior monitoring system. Vehicles can be provided with a standard cellular phone as well as the Global Positioning System (GPS), an automobile navigation or location system with an optional connection to a manned assistance facility. In the event of an accident, the phone may automatically call 911 for emergency assistance and report the exact position of the vehicle. If the vehicle also has a system as described below for monitoring each seat location, the number and perhaps the condition of the occupants could also be reported. In that way, the emergency service (EMS) would know what equipment and how many ambulances to send to the accident site. Moreover, a communication channel can be opened between the vehicle and a monitoring facility/emergency response facility or personnel to determine how badly people are injured, the number of occupants in the vehicle, and to enable directions to be provided to the occupant(s) of the vehicle to assist in any necessary first aid prior to arrival of the emergency assistance personnel. Communications between a vehicle and a remote assistance facility are also important for the purpose of diagnosing problems with the vehicle and forecasting problems with the vehicle, called prognostics. Motor vehicles contain complex mechanical systems that are monitored and regulated by computer systems such as electronic control units (ECUs) and the like. Such ECUs monitor various components of the vehicle including engine performance, carburetion, speed/acceleration control, transmission, exhaust gas recirculation (EGR), braking systems, etc. However, vehicles perform such monitoring typically only for the vehicle driver and without communication of any impending results, problems and/or vehicle malfunction to a remote site for trouble-shooting, diagnosis or tracking for data mining. In the past, systems that provide for remote monitoring did not provide for automated analysis and communication of problems or potential problems and recommendations to the driver. As a result, the vehicle driver or user is often left stranded, or irreparable damage occurs to the vehicle as a result of neglect or driving the vehicle without the user knowing the vehicle is malfunctioning until it is too late, such as low oil level and a malfunctioning warning light, fan belt about to fail, failing radiator hose etc. U.S. Pat. No. 5,400,018 (Scholl et al.) describes a system for relaying raw sensor output from an off road work site relating to the status of a vehicle to a remote location over a communications data link. The information consists of fault codes generated by sensors and electronic control modules indicating that a failure has occurred rather than forecasting a failure. The vehicle does not include a system for performing diagnosis. Rather, the raw sensor data is processed at an off-vehicle location in order to arrive at a diagnosis of the vehicle's operating condition. Bi-directional communications are described in that a request for additional information can be sent to the vehicle from the remote location with the vehicle responding and providing the requested information but no such communication takes place with the vehicle operator and not of an operator of a vehicle traveling on a road. Also, Scholl et al. does not teach the diagnostics of the problem or potential problem on the vehicle itself nor does it teach the automatic diagnostics or any prognostics. In Scholl et al. the determination of the problem occurs at the remote site by human technicians. U.S. Pat. No. 5,955,942 (Slilkin et al.) describes a method for monitoring events in vehicles in which electrical outputs representative of events in the vehicle are produced, the characteristics of one event are compared with the characteristics of other events accumulated over a given period of time and departures or variations of a given extent from the other characteristics are determined as an indication of a significant event. A warning is sent in response to the indication, including the position of the vehicle as determined by a global positioning system on the vehicle. For example, for use with a railroad car, a microprocessor responds to outputs of an accelerometer by comparing acceleration characteristics of one impact with accumulated acceleration characteristics of other impacts and determines departures of a given magnitude from the other characteristics as a failure indication which gives rise of a warning. Of course there are many areas of the country where cell phone reception is not available and thus a system that relies on the availability of such a system for diagnostics will not always be available and thus has a significant failure mode. Furthermore, it would be difficult if not impossible for such a location to have all of the information to diagnose problems with all vehicle models that are on the road and to be able to retrieve that information and act on raw data on a continuous basis to keep track of whether all vehicles on the roadways are operating properly and to forecast all potential problems with each vehicle. Thus, this function must be resident on the vehicle. Additionally is a human operator is required then the system quickly becomes unmanageable. 3.0 Definitions As used herein, a diagnosis of the “state of the vehicle” means a diagnosis of the condition of the vehicle with respect to its stability and proper running and operating condition. Thus, the state of the vehicle could be normal when the vehicle is operating properly on a highway or abnormal when, for example, the vehicle is experiencing excessive angular inclination (e.g., two wheels are off the ground and the vehicle is about to rollover), the vehicle is experiencing a crash, the vehicle is skidding, and other similar situations. A diagnosis of the state of the vehicle could also be an indication that one of the parts of the vehicle, e.g., a component, system or subsystem, is operating abnormally. As used herein, a “part” of the vehicle includes any component, sensor, system or subsystem of the vehicle such as the steering system, braking system, throttle system, navigation system, airbag system, seatbelt retractor, air bag inflation valve, air bag inflation controller and airbag vent valve, as well as those listed below in the definitions of “component” and “sensor”. As used herein, a “sensor system” includes any of the sensors listed below in the definition of “sensor” as well as any type of component or assembly of components which detect, sense or measure something. The term “vehicle” shall mean any means for transporting or carrying something including automobiles, trucks, vans, containers, trailers, boats, railroad cars and engines. The term “gage” as used herein interchangeably with the terms “gauge”, “sensor” and “sensing device”. The following additional terms will be used in the description of the invention and for the sake of clarity are defined here. The “A-pillar” of a vehicle and specifically of an automobile is defined as the first roof supporting pillar from the front of the vehicle and usually supports the front door. It is also known as the hinge pillar. The “B-Pillar” is the next roof support pillar rearward from the A-Pillar. The “C-Pillar” is the final roof support usually at or behind the rear seats. The windshield header as used herein includes the space above the front windshield including the first few inches of the roof. The headliner is the roof interior cover that extends back from the header. The term “squib” represents the entire class of electrically initiated pyrotechnic devices capable of releasing sufficient energy to cause a vehicle window to break, for example. It is also used to represent the mechanism which starts the burning of an initiator which in turn ignites the propellant within an inflator. The term “airbag module” generally connotes a unit having at least one airbag, gas generator means for producing a gas, attachment or coupling means for attaching the airbag(s) to and in fluid communication with the gas generator means so that gas is directed from the gas generator means into the airbag(s) to inflate the same, initiation means for initiating the gas generator means in response to a crash of the vehicle for which deployment of the airbag is desired and means for attaching or connecting the unit to the vehicle in a position in which the deploying airbag(s) will be effective in the passenger compartment of the vehicle. In the instant invention, the airbag module may also include occupant sensing components, diagnostic and power supply electronics and componentry which are either within or proximate to the module housing. The term “occupant protection device” or “occupant restraint device” as used herein generally includes any type of device which is deployable in the event of a crash involving the vehicle for the purpose of protecting an occupant from the effects of the crash and/or minimizing the potential injury to the occupant. Occupant restraint or protection devices thus include frontal airbags, side airbags, seatbelt tensioners, knee bolsters, side curtain airbags, externally deployable airbags and the like. “Pattern recognition” as used herein will generally mean any system which processes a signal that is generated by an object (e.g., representative of a pattern of returned or received impulses, waves or other physical property specific to and/or characteristic of and/or representative of that object) or is modified by interacting with an object, in order to determine to which one of a set of classes that the object belongs. Such a system might determine only that the object is or is not a member of one specified class, or it might attempt to assign the object to one of a larger set of specified classes, or find that it is not a member of any of the classes in the set. The signals processed are generally a series of electrical signals coming from transducers that are sensitive to acoustic (ultrasonic) or electromagnetic radiation (e.g., visible light, infrared radiation, capacitance or electric and/or magnetic fields), although other sources of information are frequently included. Pattern recognition systems generally involve the creation of a set of rules that permit the pattern to be recognized. These rules can be created by fuzzy logic systems, statistical correlations, or through sensor fusion methodologies as well as by trained pattern recognition systems such as neural networks, combination neural networks, cellular neural networks or support vector machines. A trainable or a trained pattern recognition system as used herein generally means a pattern recognition system that is taught to recognize various patterns constituted within the signals by subjecting the system to a variety of examples. The most successful such system is the neural network used either singly or as a combination of neural networks. Thus, to generate the pattern recognition algorithm, test data is first obtained which constitutes a plurality of sets of returned waves, or wave patterns, or other information radiated or obtained from an object (or from the space in which the object will be situated in the passenger compartment, i.e., the space above the seat) and an indication of the identify of that object. A number of different objects are tested to obtain the unique patterns from each object. As such, the algorithm is generated, and stored in a computer processor, and which can later be applied to provide the identity of an object based on the wave pattern being received during use by a receiver connected to the processor and other information. For the purposes here, the identity of an object sometimes applies to not only the object itself but also to its location and/or orientation in the passenger compartment. For example, a rear facing child seat is a different object than a forward facing child seat and an out-of-position adult can be a different object than a normally seated adult. Not all pattern recognition systems are trained systems and not all trained systems are neural networks. Other pattern recognition systems are based on fuzzy logic, sensor fusion, Kalman filters, correlation as well as linear and non-linear regression. Still other pattern recognition systems are hybrids of more than one system such as neural-fuzzy systems. The use of pattern recognition, or more particularly how it is used, is important to the instant invention. In the above-cited prior art, except in that assigned to the current assignee, pattern recognition which is based on training, as exemplified through the use of neural networks, is not mentioned for use in monitoring the interior passenger compartment or exterior environments of the vehicle in all of the aspects of the invention disclosed herein. Thus, the methods used to adapt such systems to a vehicle are also not mentioned. A pattern recognition algorithm will thus generally mean an algorithm applying or obtained using any type of pattern recognition system, e.g., a neural network, sensor fusion, fuzzy logic, etc. To “identify” as used herein will generally mean to determine that the object belongs to a particular set or class. The class may be one containing, for example, all rear facing child seats, one containing all human occupants, or all human occupants not sitting in a rear facing child seat, or all humans in a certain height or weight range depending on the purpose of the system. In the case where a particular person is to be recognized, the set or class will contain only a single element, i.e., the person to be recognized. A “combination neural network” as used herein will generally apply to any combination of two or more neural networks that are either connected together or that analyze all or a portion of the input data. A combination neural network can be used to divide up tasks in solving a particular occupant problem. For example, one neural network can be used to identify an object occupying a passenger compartment of an automobile and a second neural network can be used to determine the position of the object or its location with respect to the airbag, for example, within the passenger compartment. In another case, one neural network can be used merely to determine whether the data is similar to data upon which a main neural network has been trained or whether there is something radically different about this data and therefore that the data should not be analyzed. Combination neural networks can sometimes be implemented as cellular neural networks. Preferred embodiments of the invention are described below and unless specifically noted, it is the applicants' intention that the words and phrases in the specification and claims be given the ordinary and accustomed meaning to those of ordinary skill in the applicable art(s). If the applicant intends any other meaning, he will specifically state he is applying a special meaning to a word or phrase. Likewise, applicants' use of the word “function” here is not intended to indicate that the applicants seek to invoke the special provisions of 35 U.S.C. §112, sixth paragraph, to define their invention. To the contrary, if applicants wish to invoke the provisions of 35 U.S.C. §112, sixth paragraph, to define their invention, they will specifically set forth in the claims the phrases “means for” or “step for” and a function, without also reciting in that phrase any structure, material or act in support of the function. Moreover, even if applicants invoke the provisions of 35 U.S.C. §112, sixth paragraph, to define their invention, it is the applicants' intention that their inventions not be limited to the specific structure, material or acts that are described in the preferred embodiments herein. Rather, if applicants claim their inventions by specifically invoking the provisions of 35 U.S.C. §112, sixth paragraph, it is nonetheless their intention to cover and include any and all structure, materials or acts that perform the claimed function, along with any and all known or later developed equivalent structures, materials or acts for performing the claimed function. OBJECTS AND SUMMARY OF THE INVENTION 1.0 Telematics Objects of the inventions disclosed herein include: 1. To provide new and improved weight or load measuring sensors, switches, temperature sensors, acceleration sensors, angular position sensors, angular rate sensors, angular acceleration sensors, proximity sensors, rollover sensors, occupant presence and position sensors, strain sensors and humidity sensors which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 2. To provide new and improved sensors for detecting the presence of fluids or gases which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 3. To provide new and improved sensors for detecting chemicals which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 4. To utilize any of the foregoing sensors for a vehicular component control system in which a component, system or subsystem in the vehicle is controlled based on the information provided by the sensor. Additionally, the information provided by the sensor can be transmitted via a telematics link to one or more remote facilities for further analysis. 5. To provide a new and improved method and system for diagnosing components in a vehicle and the operating status of the vehicle and alerting the vehicle's dealer, or another repair facility, via a telematics link that a component of the vehicle is functioning abnormally and may be in danger of failing. 6. To provide a new and improved method and apparatus for obtaining information about a vehicle system and components in the vehicle in conjunction with failure of the component or the vehicle and sending this information to the vehicle manufacturer. 7. To provide a new and improved method and system for diagnosing components in a vehicle by monitoring the patterns of signals emitted from the vehicle components and, through the use of pattern recognition technology, forecasting component failures before they occur. Vehicle component behavior is thus monitored over time in contrast to systems that wait until a serious condition occurs. The forecast of component failure can be transmitted to a remote location via a telematics link. 8. To provide a new and improved on-board vehicle diagnostic module utilizing pattern recognition technologies which are trained to differentiate normal from abnormal component behavior. The diagnosis of component behavior can be transmitted to a remote location via a telematics link. 9. To provide a diagnostic module that determines whether a component is operating normally or abnormally based on a time series of data from a single sensor or from multiple sensors that contain a pattern indicative of the operating status of the component. The diagnosis of component operation can be transmitted to a remote location via a telematics link. 10. To provide a diagnostic module that determines whether a component is operating normally or abnormally based on data from one or more sensors that are not directly associated with the component, i.e., do not depend on the operation of the component. The diagnosis of component operation can be transmitted to a remote location via a telematics link. 11. To incorporate surface acoustic wave technology into sensors on a vehicle with the data obtained by the sensors being transmittable via a telematics link to a remote location. 12. To provide new and improved sensors which obtain and provide information about the vehicle, about individual components, systems, vehicle occupants, subsystems, or about the roadway, ambient atmosphere, travel conditions and external objects with the data obtained by the sensors being transmittable via a telematics link to a remote location. 13. To alert the dealer, or other repair facility, that a component of the vehicle is functioning differently than normal and is in danger of failing. 14. To provide a device which provides information to the vehicle manufacturer of the events leading to a component failure. 15. To provide new and improved sensors for a vehicle which wirelessly transmits information about a state measured or detected by the sensor. In order to achieve these objects and others, an information management and monitoring system for a vehicle in accordance with the invention includes a vehicle monitoring system including a plurality of sensors for monitoring components of the vehicle, a diagnostic module arranged on the vehicle and coupled to the vehicle monitoring system to receive and process data about the monitored components therefrom, and a remote service center capable of servicing the vehicle components. A communication system, e.g., a cellular telephone capable of voice communications, is arranged on the vehicle and coupled to the diagnostic module to enable communications of data from the diagnostic module to the remote service center, for example using a satellite or relay link, such that the remote service center receives data about the monitored components of the vehicle. The remote service center can be situated at a dealer which can then have its personnel contact the driver or another occupant of the vehicle, e.g., via the telephone, to schedule service of the vehicle, the service being determined based on the communicated data from the diagnostic module on the vehicle. The diagnostic module may derive diagnostic data from data about the monitored components provided by the sensors of the vehicle monitoring system, e.g., an indication of a potential failure of one of the components of the vehicle. A user interactive device, such as a display, may be coupled to and controlled by the diagnostic module such that a message about the component failure may be provided to the driver or other vehicle occupant. A vehicle bus may be provided to couple the diagnostic module, vehicle monitoring system and communication system. A method for information management and monitoring of a vehicle includes arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle, arranging a diagnostic module on the vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on the vehicle to the diagnostic module, and establishing communications between the diagnostic module and a remote service center capable of servicing the monitored components to enable transmission of data between the diagnostic module and the remote service center. As such, the remote service center receives data about the monitored components of the vehicle and can direct personnel to contact the driver or other occupant of the vehicle to schedule servicing thereof, with the service being required being based on the communicated data. The same variations to the system described above can be applied in this method as well. A method for scheduling servicing of a vehicle in accordance with the invention includes arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle, arranging a diagnostic module on the vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on the vehicle to the diagnostic module, establishing communications between the diagnostic module and a dealer capable of servicing the monitored components to enable transmission of data between the diagnostic module and the dealer such that the dealer receives data about the monitored components of the vehicle, and upon receiving data from the diagnostic module at the dealer, contacting the vehicle owner to schedule repair or maintenance of the vehicle. The same variations to the system described above can be applied in this method as well. A method for information management and monitoring of a plurality of vehicles in accordance with the invention is designed for manufacturers and other parties interested in statistical failure of vehicle components and includes arranging a vehicle monitoring system including a plurality of sensors on each vehicle to monitor components of the vehicle, arranging a diagnostic module on each vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on each vehicle to the diagnostic module, establishing communications between the diagnostic module and a data gathering facility which accumulates information about the failure rate of the components to enable transmission of data between the diagnostic module and the data gathering facility such that the data gathering facility receives data about the monitored components of the vehicle, and accumulating date from the vehicle at the data gathering facility to enable calculation of statistics about failure rate of the components. Diagnostic data may be derived in the diagnostic module from the data about the monitored components provided by the vehicle monitoring system, e.g., using a pattern recognition algorithm, and the derived data transmitted to the data gathering facility. The derived data may be an indication of a potential or actual failure of one of the components of the vehicle. 2. Diagnostics 2.1 General Diagnostics Further objects of inventions disclosed herein are: 1. To prevent vehicle breakdowns. 2. To alert the driver of the vehicle that a component of the vehicle is functioning differently than normal and might be in danger of failing. 3. To provide an early warning of a potential component failure and to thereby minimize the cost of repairing or replacing the component. 4. To provide a device which will capture available information from signals emanating from vehicle components for a variety of uses such as current and future vehicle diagnostic purposes. 5. To provide a device that uses information from existing sensors for new purposes thereby increasing the value of existing sensors and, in some cases, eliminating the need for sensors that provide redundant information. 6. To provide a device which analyzes vibrations from various vehicle components that are transmitted through the vehicle structure and sensed by existing vibration sensors such as vehicular crash sensors used with airbag systems or by special vibration sensors, accelerometers, or gyroscopes. 2.2 Pattern Recognition Further objects of inventions disclosed herein are: 1. To provide a device which is trained to recognize deterioration in the performance of a vehicle component, or of the entire vehicle, based on information in signals emanating from the component or from vehicle angular and linear accelerations. 2. To apply pattern recognition techniques based on training to diagnosing potential vehicle component failures. 3. To apply trained pattern recognition techniques using multiple sensors to provide an early prediction of the existence and severity of an accident. 2.3 Vehicle or Component Control Further objects of inventions disclosed herein are: 1. To utilize pattern recognition techniques and the output from multiple sensors to determine at an early stage that a vehicle rollover might occur and to take corrective action through control of the vehicle acceleration, brakes and steering to prevent the rollover or if it is preventable, to deploy side head protection airbags to reduce the injuries. 2. To apply component diagnostic techniques in combination with intelligent or smart highways wherein vehicles may be automatically guided without manual control in order to permit the orderly exiting of the vehicle from a restricted roadway prior to a breakdown of the vehicle. 3. To use the output from multiple sensors to determine that the vehicle is skidding or sliding and to send messages to the various vehicle control systems to activate the throttle, brakes and/or steering to correct for the vehicle sliding or skidding motion. BRIEF DESCRIPTION OF THE DRAWINGS The following drawings are illustrative of embodiments of the system developed or adapted using the teachings of these inventions and are not meant to limit the scope of the invention as encompassed by the claims. FIG. 1 is a schematic illustration of a generalized component with several signals being emitted and transmitted along a variety of paths, sensed by a variety of sensors and analyzed by the diagnostic module in accordance with the invention and for use in a method in accordance with the invention. FIG. 2 is a schematic of one pattern recognition methodology known as a neural network which may be used in a method in accordance with the invention. FIG. 3 is a schematic of a vehicle with several components and several sensors and a total vehicle diagnostic system in accordance with the invention utilizing a diagnostic module in accordance with the invention and which may be used in a method in accordance with the invention. FIG. 4 is a flow diagram of information flowing from various sensors onto the vehicle data bus and thereby into the diagnostic module in accordance with the invention with outputs to a display for notifying the driver, and to the vehicle cellular phone for notifying another person, of a potential component failure. FIG. 5 is an overhead view of a roadway with vehicles and a SAW road temperature and humidity monitoring sensor. FIG. 5A is a detail drawing of the monitoring sensor of FIG. 5. FIG. 6 is a perspective view of a SAW system for locating a vehicle on a roadway, and on the earth surface if accurate maps are available, and also illustrates the use of a SAW transponder in the license plate for the location of preceding vehicles and preventing rear end impacts. FIG. 7 is a partial cutaway view of a section of a fluid reservoir with a SAW fluid pressure and temperature sensor for monitoring oil, water, or other fluid pressure. FIG. 8 is a perspective view of a vehicle suspension system with SAW load sensors. FIG. 8A is a cross section detail view of a vehicle spring and shock absorber system with a SAW torque sensor system mounted for measuring the stress in the vehicle spring of the suspension system of FIG. 8. FIG. 8B is a detail view of a SAW torque sensor and shaft compression sensor arrangement for use with the arrangement of FIG. 8. FIG. 9 is a cutaway view of a vehicle showing possible mounting locations for vehicle interior temperature, humidity, carbon dioxide, carbon monoxide, alcohol or other chemical or physical property measuring sensors. FIG. 10A is a perspective view of a SAW tilt sensor using four SAW assemblies for tilt measurement and one for temperature. FIG. 10B is a top view of a SAW tilt sensor using three SAW assemblies for tilt measurement each one of which can also measure temperature. FIG. 11 is a perspective exploded view of a SAW crash sensor for sensing frontal, side or rear crashes. FIG. 12 is a perspective view with portions cutaway of a SAW based vehicle gas gage. FIG. 12A is a top detailed view of a SAW pressure and temperature monitor for use in the system of FIG. 12. FIG. 13A is a schematic of a prior art deployment scheme for an airbag module. FIG. 13B is a schematic of a deployment scheme for an airbag module in accordance with the invention. FIG. 14 is a schematic of a vehicle with several accelerometers and/or gyroscopes at preferred locations in the vehicle. FIG. 15A illustrates a driver with a timed RFID standing with groceries by a closed trunk. FIG. 15B illustrates the driver with the timed RFID 5 seconds after the trunk has been opened. FIG. 15C illustrates a trunk opening arrangement for a vehicle in accordance with the invention. FIG. 16A is a view of a SAW switch sensor for mounting on or within a surface such as a vehicle armrest. FIG. 16B is a detailed perspective view of the device of FIG. 16A with the force-transmitting member rendered transparent. FIG. 16C is a detailed perspective view of an alternate SAW device for use in FIGS. 16A and 16B showing the use of one of two possible switches, one that activates the SAW and the other that suppresses the SAW. FIG. 17A is a detailed perspective view of a polymer and mass on SAW accelerometer for use in crash sensors, vehicle navigation, etc. FIG. 17B is a detailed perspective view of a normal mass on SAW accelerometer for use in crash sensors, vehicle navigation, etc. FIG. 18 is a view of a prior art SAW gyroscope that can be used with this invention. FIGS. 19A, 19B and 19C are block diagrams of three interrogators that can be used with this invention to interrogate several different devices. FIG. 20 is a side view with parts cutaway and removed of a vehicle showing the passenger compartment containing a rear facing child seat on the front passenger seat and a preferred mounting location for an occupant and rear facing child seat presence detector. FIG. 21 is a partial cutaway view of a vehicle drives wearing a seatbelt with SAW force sensors. FIG. 22 illustrates a strain gage on a bolt weight sensor. FIGS. 23A, 23B, 23C, 23D and 23E are views of occupant seat weight sensors using a slot spanning SAW strain gage and other strain concentrating designs. FIG. 24 is a flow chart of the methods for automatically monitoring a vehicular component in accordance with the invention. FIG. 25 is a schematic illustration of the components used in the methods for automatically monitoring a vehicular component. FIG. 26 is a side view with parts cutaway and removed showing schematically the interface between the vehicle interior monitoring system of this invention and the vehicle cellular communication system. FIG. 27 is a diagram of one exemplifying embodiment of the invention. FIG. 28 is a perspective view of a carbon dioxide SAW sensor for mounting in the trunk lid for monitoring the inside of the trunk for detecting trapped children or animals. FIG. 28A is a detailed view of the SAW carbon dioxide sensor of FIG. 28. FIG. 29 is a schematic view of overall telematics system in accordance with the invention. FIG. 30 is a perspective view of the combination of an occupant position sensor, diagnostic electronics and power supply and airbag module designed to prevent the deployment of the airbag if the seat is unoccupied. FIG. 31 shows the application of a preferred implementation of the invention for mounting on the rear of front seats to provide protection for rear seat occupants. FIG. 32 is another implementation of the invention incorporating the electronic components into and adjacent the airbag module. FIGS. 33A, 33B, 33C and 33D are different views of an automotive connector for use with a coaxial electrical bus for a motor vehicle illustrating the teachings of this invention. DETAILED DESCRIPTION OF THE INVENTION 1.1 General Diagnostics A preferred embodiment of the vehicle diagnostic unit described below performs the diagnosis, i.e., processes the input from the various sensors, on the vehicle using for example a processor embodying a pattern recognition technique such as a neural network. The processor thus receives data or signals from the sensors and generates an output indicative or representative of the operating conditions of the vehicle or its component. A signal could thus be generated indicative of an under-inflated tire, or an overheating engine. For the discussion below, the following terms are defined as follows: The term “component” as used herein generally refers to any part or assembly of parts which is mounted to or a part of a motor vehicle and which is capable of emitting a signal representative of its operating state. The following is a partial list of general automobile and truck components, the list not being exhaustive: engine; transmission; brakes and associated brake assembly; tires; wheel; steering wheel and steering column assembly; water pump; alternator; shock absorber; wheel mounting assembly; radiator; battery; oil pump; fuel pump; air conditioner compressor; differential gear; exhaust system; fan belts; engine valves; steering assembly; vehicle suspension including shock absorbers; vehicle wiring system; and engine cooling fan assembly. The term “sensor” as used herein generally refers to any measuring, detecting or sensing device mounted on a vehicle or any of its components including new sensors mounted in conjunction with the diagnostic module in accordance with the invention. A partial, non-exhaustive list of common sensors mounted on an automobile or truck is as follows: airbag crash sensor; accelerometer; microphone; camera; antenna, capacitance sensor or other electromagnetic wave sensor; stress or strain sensor; pressure sensor; weight sensor; magnetic field sensor; coolant thermometer; oil pressure sensor; oil level sensor; air flow meter; voltmeter; ammeter; humidity sensor; engine knock sensor; oil turbidity sensor; throttle position sensor; steering wheel torque sensor; wheel speed sensor; tachometer; speedometer; other velocity sensors; other position or displacement sensors; oxygen sensor; yaw, pitch and roll angular sensors; clock; odometer; power steering pressure sensor; pollution sensor; fuel gauge; cabin thermometer; transmission fluid level sensor; gyroscopes or other angular rate sensors including yaw, pitch and roll rate sensors; coolant level sensor; transmission fluid turbidity sensor; brake pressure sensor; tire pressure sensor; tire temperature sensor, tire acceleration sensor; GPS receiver; DGPS receiver; and coolant pressure sensor. The term “signal” as used herein generally refers to any time-varying output from a component including electrical, acoustic, thermal, electromagnetic radiation or mechanical vibration. Sensors on a vehicle are generally designed to measure particular parameters of particular vehicle components. However, frequently these sensors also measure outputs from other vehicle components. For example, electronic airbag crash sensors currently in use contain an accelerometer for determining the accelerations of the vehicle structure so that the associated electronic circuitry of the airbag crash sensor can determine whether a vehicle is experiencing a crash of sufficient magnitude so as to require deployment of the airbag. This accelerometer continuously monitors the vibrations in the vehicle structure regardless of the source of these vibrations. If a wheel is out of balance, or if there is extensive wear of the parts of the front wheel mounting assembly, or wear in the shock absorbers, the resulting abnormal vibrations or accelerations can, in many cases, be sensed by the crash sensor accelerometer. There are other cases, however, where the sensitivity or location of the airbag crash sensor accelerometer is not appropriate and one or more additional accelerometers may be mounted onto a vehicle for the purposes of this invention. Some airbag crash sensors are not sufficiently sensitive accelerometers or have sufficient dynamic range for the purposes herein. For example, a technique for some implementations of this invention is the use of multiple accelerometers and/or microphones that will allow the system to locate the source of any measured vibrations based on the time of flight, time of arrival, direction of arrival and/or triangulation techniques. Once a distributed accelerometer installation has been implemented to permit this source location, the same sensors can be used for smarter crash sensing as it will permit the determination of the location of the impact on the vehicle. Once the impact location is known, a highly tailored algorithm can be used to accurately forecast the crash severity making use of knowledge of the force vs. crush properties of the vehicle at the impact location. Every component of a vehicle emits various signals during its life. These signals can take the form of electromagnetic radiation, acoustic radiation, thermal radiation, vibrations transmitted through the vehicle structure and voltage or current fluctuations, depending on the particular component. When a component is functioning normally, it may not emit a perceptible signal. In that case, the normal signal is no signal, i.e., the absence of a signal. In most cases, a component will emit signals that change over its life and it is these changes which typically contain information as to the state of the component, e.g., whether failure of the component is impending. Usually components do not fail without warning. However, most such warnings are either not perceived or if perceived, are not understood by the vehicle operator until the component actually fails and, in some cases, a breakdown of the vehicle occurs. In a few years, it is expected that various roadways will have systems for automatically guiding vehicles operating thereon. Such systems have been called “smart highways” and are part of the field of intelligent transportation systems (ITS). If a vehicle operating on such a smart highway were to breakdown, serious disruption of the system could result and the safety of other users of the smart highway could be endangered. When a vehicle component begins to change its operating behavior, it is not always apparent from the particular sensors which are monitoring that component, if any. The output from any one of these sensors can be normal even though the component is failing. By analyzing the output of a variety of sensors, however, the pending failure can be diagnosed. For example, the rate of temperature rise in the vehicle coolant, if it were monitored, might appear normal unless it were known that the vehicle was idling and not traveling down a highway at a high speed. Even the level of coolant temperature which is in the normal range could be in fact abnormal in some situations signifying a failing coolant pump, for example, but not detectable from the coolant thermometer alone. The pending failure of some components is difficult to diagnose and sometimes the design of the component requires modification so that the diagnosis can be more readily made. A fan belt, for example, frequently begins failing as a result of a crack of the inner surface. The belt can be designed to provide a sonic or electrical signal when this cracking begins in a variety of ways. Similarly, coolant hoses can be designed with an intentional weak spot where failure will occur first in a controlled manner that can also cause a whistle sound as a small amount of steam exits from the hose. This whistle sound can then be sensed by a general purpose microphone, for example. In FIG. 1, a generalized component 35 emitting several signals which are transmitted along a variety of paths, sensed by a variety of sensors and analyzed by the diagnostic device in accordance with the invention is illustrated schematically. Component 35 is mounted to a vehicle 52 and during operation it emits a variety of signals such as acoustic 36, electromagnetic radiation 37, thermal radiation 38, current and voltage fluctuations in conductor 39 and mechanical vibrations 40. Various sensors are mounted in the vehicle to detect the signals emitted by the component 35. These include one or more vibration sensors (accelerometers) 44, 46 and/or gyroscopes also mounted to the vehicle, one or more acoustic sensors 41, 47, electromagnetic radiation sensors 42, heat radiation sensors 43 and voltage or current sensors 45. In addition, various other sensors 48, 49 measure other parameters of other components that in some manner provide information directly or indirectly on the operation of component 35. All of the sensors illustrated on FIG. 1 can be connected to a data bus 50. A diagnostic module 51, in accordance with the invention, can also be attached to the vehicle data bus 5 and receives the signals generated by the various sensors. The sensors may however be wirelessly connected to the diagnostic module 51 and be integrated into a wireless power and communications system or a combination of wired and wireless connections. The diagnostic module 51 will analyze the received data in light of the data values or patterns itself either statically or over time. In some cases, a pattern recognition algorithm as discussed below will be used and in others, a deterministic algorithm may also be used either alone or in combination with the pattern recognition algorithm. Additionally, when a new data value or sequence is discovered the information can be sent to an off-vehicle location, perhaps a dealer or manufacturer site, and a search can be made for other similar cases and the results reported back to the vehicle. Also additionally as more and more vehicles are reporting cases that perhaps are also examined by engineers or mechanics, the results can be sent to the subject vehicle or to all similar vehicles and the diagnostic software updated automatically. Thus, all vehicles can have the benefit of all information relative to performing the diagnostic function. Similarly, the vehicle dealers and manufacturers can also have up-to-date information as to how a particular class or model of vehicle is performing. This telematics function is discussed in more detail elsewhere herein. By means of this system, a vehicle diagnostic system can better and better be able to predict component failures long before they occur and thus prevent on-road problems. An important function that can be performed by the diagnostic system herein is to substantially diagnose its own problems rather then, as is the case with the prior art, forwarding raw data to a central site for diagnosis. Eventually, a prediction as to the failure point of all significant components can be made and the owner can have a prediction that the fan belt will last another 20,000 miles, or that the tires should be rotated in 2,000 miles or replaced in 20,000 miles. This information can be displayed or reported orally or sent to the dealer who can then schedule a time for the customer to visit the dealership or for the dealer to visit the vehicle wherever it is located. If it is displayed, it can be automatically displayed periodically or when there is urgency or whenever the operator desires. The display can be located at any convenient place such as the dashboard or it can be a heads-up display. The display can be any convenient technology such as an LCD display or an OLED based display. It is worth emphasizing that in many cases, it is the rate that a parameter is changing that can be as or more important than the actual value in predicting when a component is likely to fail. In a simple case when a tire is losing pressure, for example, it is a quite different situation if it is losing one psi per day or one psi per minute. Similarly for the tire case, if the tire is heating up at one degree per hour or 100 degrees per hour may be more important in predicting failure due to delamination or overloading than the particular temperature of the tire. The diagnostic module, or other component, can also consider situation awareness factors such as the age or driving habits of the operator, the location of the vehicle (e.g., is it in the desert, in the arctic in winter), the season, the weather forecast, the length of a proposed trip, the number and location of occupants of the vehicle etc. The system may even put limits on the operation of the vehicle such as turning off unnecessary power consuming components if the alternator is failing or limiting the speed of the vehicle if the driver is an elderly woman sitting close to the steering wheel, for example. 1.2 Pattern Recognition In accordance with the invention, each of the signals emitted by the vehicle components can be converted into electrical signals and then digitized (i.e., the analog signal is converted into a digital signal) to create numerical time series data which is entered into a processor. Pattern recognition algorithms can be applied in the processor to attempt to identify and classify patterns in this time series data. For a particular component, such as a tire for example, the algorithm attempts to determine from the relevant digital data whether the tire is functioning properly or whether it requires balancing, additional air, or perhaps replacement. Frequently, the data entered into the computer needs to be preprocessed before being analyzed by a pattern recognition algorithm. The data from a wheel speed sensor, for example, might be used “as is” for determining whether a particular tire is operating abnormally in the event it is unbalanced, whereas the integral of the wheel speed data over a long time period (a preprocessing step), when compared to such sensors on different wheels, might be more useful in determining whether a particular tire is going flat and therefore needs air. This is the basis of some tire monitors now on the market. In some cases, the frequencies present in a set of data are a better predictor of component failures than the data itself. For example, when a motor begins to fail due to worn bearings, certain characteristic frequencies began to appear. In most cases, the vibrations arising from rotating components, such as the engine, will be normalized based on the rotational frequency. Moreover, the identification of which component is causing vibrations present in the vehicle structure can frequently be accomplished through a frequency analysis of the data. For these cases, a Fourier transformation of the data can be made prior to entry of the data into a pattern recognition algorithm. Other mathematical transformations are also made for particular pattern recognition purposes in practicing the teachings of this invention. Some of these include shifting and combining data to determine phase changes for example, differentiating the data, filtering the data and sampling the data. Also, there exist certain more sophisticated mathematical operations that attempt to extract or highlight specific features of the data. This invention contemplates the use of a variety of these preprocessing techniques and the choice of which one or ones to use is left to the skill of the practitioner designing a particular diagnostic module. As shown in FIG. 1, the diagnostic module 51 has access to the output data of each of the sensors that are known to have or potentially may have information relative to or concerning the component 35. This data appears as a series of numerical values each corresponding to a measured value at a specific point in time. The cumulative data from a particular sensor is called a time series of individual data points. The diagnostic module 51 compares the patterns of data received from each sensor individually, or in combination with data from other sensors, with patterns for which the diagnostic module has been trained to determine whether the component is functioning normally or abnormally. Important to some embodiments of this invention is the manner in which the diagnostic module 51 determines a normal pattern from an abnormal pattern and the manner in which it decides what data to use from the vast amount of data available. This is accomplished using pattern recognition technologies such as artificial neural networks and training and in particular, combination neural networks as described in co-pending U.S. patent application Ser. No. 10/413,426 filed Apr. 14, 2003. The theory of neural networks including many examples can be found in several books on the subject including: (1) Techniques And Application Of Neural Networks, edited by Taylor, M. and Lisboa, P., Ellis Horwood, West Sussex, England, 1993; (2) Naturally Intelligent Systems, by Caudill, M. and Butler, C., MIT Press, Cambridge Mass., 1990; (3) J. M. Zaruda, Introduction to Artificial Neural Systems, West publishing Co., N.Y., 1992, (4) Digital Neural Networks, by Kung, S. Y., PTR Prentice Hall, Englewood Cliffs, N.J., 1993, Eberhart, R., Simpson, P., (5) Dobbins, R., Computational Inteligence PC Tools. Academic Press, Inc., 1996, Orlando, Fla., (6) Cristianini, N. and Shawe-Taylor, J. An Introduction to Support Vector Machines and other kemal-based learning methods, Cambridge University Press, Cambridge England, 2000; (7) Proceedings of the 2000 6th IEEE International Workshop on Cellular Neural Networks and their Applications (CNNA 2000), IEEE, Piscataway N.J.; and (8) Sinha, N. K. and Gupta, M.M. Soft Computing & Intelligent Systems, Academic Press 2000 San Diego, Calif.,. The neural network pattern recognition technology is one of the most developed of pattern recognition technologies. The invention described herein frequently uses combinations of neural networks to improve the pattern recognition process, as discussed in detail in U.S. patent application Ser. No. 10/413,426 referenced above. The neural network pattern recognition technology is one of the most developed of pattern recognition technologies. The neural network will be used here to illustrate one example of a pattern recognition technology but it is emphasized that this invention is not limited to neural networks. Rather, the invention may apply any known pattern recognition technology including various segmentation techniques, sensor fusion and various correlation technologies. A brief description of a particular simple example of a neural network pattern recognition technology is set forth below. Neural networks are constructed of processing elements known as neurons that are interconnected using information channels call interconnects and are arranged in a plurality of layers. Each neuron can have multiple inputs but only one output. Each output however is usually connected to many, frequently all, other neurons in the next layer. The neurons in the first layer operate collectively on the input data as described in more detail below. Neural networks learn by extracting relational information from the data and the desired output. Neural networks have been applied to a wide variety of pattern recognition problems including automobile occupant sensing, speech recognition, optical character recognition and handwriting analysis. To train a neural network, data is provided in the form of one or more time series that represents the condition to be diagnosed as well as normal operation. As an example, the simple case of an out-of-balance tire will be used. Various sensors on the vehicle can be used to extract information from signals emitted by the tire such as an accelerometer, a torque sensor on the steering wheel, the pressure output of the power steering system, a tire pressure monitor or tire temperature monitor. Other sensors that might not have an obvious relationship to tire unbalance (or imbalance) are also included such as, for example, the vehicle speed or wheel speed that can be determined from the anti-lock brake (ABS) system. Data is taken from a variety of vehicles where the tires were accurately balanced under a variety of operating conditions also for cases where varying amounts of tire unbalance was intentionally introduced. Once the data had been collected, some degree of preprocessing or feature extraction is usually performed to reduce the total amount of data fed to the neural network. In the case of the unbalanced tire, the time period between data points might be selected such that there are at least ten data points per revolution of the wheel. For some other application, the time period might be one minute or one millisecond. Once the data has been collected, it is processed by a neural network-generating program, for example, if a neural network pattern recognition system is to be used. Such programs are available commercially, e.g., from NeuralWare of Pittsburgh, Pa. or from International Scientific Research, Inc., of Romeo, Mich. for modular neural networks. The program proceeds in a trial and error manner until it successfully associates the various patterns representative of abnormal behavior, an unbalanced tire in this case, with that condition. The resulting neural network can be tested to determine if some of the input data from some of the sensors, for example, can be eliminated. In this manner, the engineer can determine what sensor data is relevant to a particular diagnostic problem. The program then generates an algorithm that is programmed onto a microprocessor, microcontroller, neural processor, FPGA, or DSP (herein collectively referred to as a microprocessor or processor). Such a microprocessor appears inside the diagnostic module 51 in FIG. 1. Once trained, the neural network, as represented by the algorithm, will now recognize an unbalanced tire on a vehicle when this event occurs. At that time, when the tire is unbalanced, the diagnostic module 51 will output a message to the driver indicating that the tire should now be balanced as described in more detail below. The message to the driver is provided by an output device coupled to or incorporated within the module 51 and may be, e.g., an icon or text display, a light on the dashboard, a vocal tone or any other recognizable indication apparatus. A similar message may also be sent to the dealer or other repair facility or remote facility via a communications channel between the vehicle and the dealer or repair facility. It is important to note that there may be many neural networks involved in a total vehicle diagnostic system. These can be organized either in parallel, series, as an ensemble, cellular neural network or as a modular neural network system. In one implementation of a modular neural network, a primary neural network identifies that there is an abnormality and tries to identify the likely source. Once a choice has been made as to the likely source of the abnormality, another, specific neural network of a group of neural networks can be called upon to determine the exact cause of the abnormality. In this manner, the neural networks are arranged in a tree pattern with each neural network trained to perform a particular pattern recognition task. Discussions on the operation of a neural network can be found in the above references on the subject and are understood by those skilled in the art. Neural networks are the most well-known of the pattern recognition technologies based on training, although neural networks have only recently received widespread attention and have been applied to only very limited and specialized problems in motor vehicles such as occupant sensing and engine control. Other non-training based pattern recognition technologies exist, such as fuzzy logic. However, the programming required to use fuzzy logic, where the patterns must be determine by the programmer, usually render these systems impractical for general vehicle diagnostic problems such as described herein (although their use is not impossible in accordance with the teachings of the invention). Therefore, preferably the pattern recognition systems that learn by training are used herein. It should be noted that neural networks are frequently combined with fuzzy logic and such a combination is contemplated herein. The neural network is the first highly successful of what will be a variety of pattern recognition techniques based on training. There is nothing that suggests that it is the only or even the best technology. The characteristics of all of these technologies which render them applicable to this general diagnostic problem include the use of time-based input data and that they are trainable. In most cases, the pattern recognition technology learns from examples of data characteristic of normal and abnormal component operation. A diagram of one example of a neural network used for diagnosing an unbalanced tire, for example, based on the teachings of this invention is shown in FIG. 2. The process can be programmed to periodically test for an unbalanced tire. Since this need be done only infrequently, the same processor can be used for many such diagnostic problems. When the particular diagnostic test is run, data from the previously determined relevant sensor(s) is preprocessed and analyzed with the neural network algorithm. For the unbalanced tire, using the data from an accelerometer for example, the digital acceleration values from the analog-to-digital converter in the accelerometer are entered into nodes 1 through n and the neural network algorithm compares the pattern of values on nodes 1 through n with patterns for which it has been trained as follows. Each of the input nodes is connected to each of the second layer nodes, h-1, h-2, . . . , h-n, called the hidden layer, either electrically as in the case of a neural computer, or through mathematical functions containing multiplying coefficients called weights, in the manner described in more detail in the above references. At each hidden layer node, a summation occurs of the values from each of the input layer nodes, which have been operated on by functions containing the weights, to create a node value. Similarly, the hidden layer nodes are, in a like manner, connected to the output layer node(s), which in this example is only a single node 0 representing the decision to notify the driver, and/or a remote facility, of the unbalanced tire. During the training phase, an output node value of 1, for example, is assigned to indicate that the driver should be notified and a value of 0 is assigned to not notifying the driver. Once again, the details of this process are described in above-referenced texts and will not be presented in detail here. In the example above, twenty input nodes were used, five hidden layer nodes and one output layer node. In this example, only one sensor was considered and accelerations from only one direction were used. If other data from other sensors such as accelerations from the vertical or lateral directions were also used, then the number of input layer nodes would increase. Again, the theory for determining the complexity of a neural network for a particular application has been the subject of many technical papers and will not be presented in detail here. Determining the requisite complexity for the example presented here can be accomplished by those skilled in the art of neural network design. Also one particular preferred type of neural network has been discussed. Many other types exist as discussed in the above references and this invention is not limited to the particular type discussed here. Briefly, the neural network described above defines a method, using a pattern recognition system, of sensing an unbalanced tire and determining whether to notify the driver, and/or a remote facility, and comprises the steps of: (a) obtaining an acceleration signal from an accelerometer mounted on a vehicle; (b) converting the acceleration signal into a digital time series; (c) entering the digital time series data into the input nodes of the neural network; (d) performing a mathematical operation on the data from each of the input nodes and inputting the operated on data into a second series of nodes wherein the operation performed on each of the input node data prior to inputting the operated-on value to a second series node is different from that operation performed on some other input node data (e.g., a different weight value can be used); (e) combining the operated-on data from most or all of the input nodes into each second series node to form a value at each second series node; (f) performing a mathematical operation on each of the values on the second series of nodes and inputting this operated-on data into an output series of nodes wherein the operation performed on each of the second series node data prior to inputting the operated-on value to an output series node is different from that operation performed on some other second series node data; (g) combining the operated-on data from most or all of the second series nodes into each output series node to form a value at each output series node; and, (h) notifying a driver if the value on one output series node is within a selected range signifying that a tire requires balancing. This method can be generalized to a method of predicting that a component of a vehicle will fail comprising the steps of: (a) sensing a signal emitted from the component; (b) converting the sensed signal into a digital time series; (c) entering the digital time series data into a pattern recognition algorithm; (d) executing the pattern recognition algorithm to determine if there exists within the digital time series data a pattern characteristic of abnormal operation of the component; and (e) notifying a driver and/or a remote facility if the abnormal pattern is recognized. The particular neural network described and illustrated above contains a single series of hidden layer nodes. In some network designs, more than one hidden layer is used, although only rarely will more than two such layers appear. There are of course many other variations of the neural network architecture illustrated above which appear in the referenced literature. For the purposes herein, therefore, “neural network” will be defined as a system wherein the data to be processed is separated into discrete values which are then operated on and combined in at least a two stage process and where the operation performed on the data at each stage is in general different for each discrete value and where the operation performed is at least determined through a training process. A different operation here is meant any difference in the way that the output of a neuron is treated before it is inputted into another neuron such as multiplying it by a different weight or constant. The implementation of neural networks can take on at least two forms, an algorithm programmed on a digital microprocessor, FPGA, DSP or in a neural computer (including a cellular neural network or support vector machine). In this regard, it is noted that neural computer chips are now becoming available. In the example above, only a single component failure was discussed using only a single sensor since the data from the single sensor contains a pattern which the neural network was trained to recognize as either normal operation of the component or abnormal operation of the component. The diagnostic module 870 contains preprocessing and neural network algorithms for a number of component failures. The neural network algorithms are generally relatively simple, requiring only a relatively small number of lines of computer code. A single general neural network program can be used for multiple pattern recognition cases by specifying different coefficients for the various terms, one set for each application. Thus, adding different diagnostic checks has only a small affect on the cost of the system. Also, the system has available to it all of the information available on the data bus. During the training process, the pattern recognition program sorts out from the available vehicle data on the data bus or from other sources, those patterns that predict failure of a particular component. If more than one sensor is used to sense the output from a component, such as two spaced-apart microphones or acceleration sensors, then the location of the component can sometimes be determined by triangulation based on the phase difference or time of arrival of the signals to the different sensors. In this manner, a particular vibrating tire can be identified, for example. Since each tire on a vehicle does not always make the same number of revolutions in a given time period, a tire can be identified by comparing the wheel sensor output with the vibration or other signal from the tire to identify the failing tire. The phase of the failing tire will change relative to the other tires, for example. In FIG. 3, a schematic of a vehicle with several components and several sensors is shown in their approximate locations on a vehicle along with a total vehicle diagnostic system in accordance with the invention utilizing a diagnostic module in accordance with the invention. A flow diagram of information passing from the various sensors shown in FIG. 3 onto the vehicle data bus and thereby into the diagnostic device in accordance with the invention is shown in FIG. 4 along with outputs to a display for notifying the driver and to the vehicle cellular phone, or other communication device, for notifying the dealer, vehicle manufacturer or other entity concerned with the failure of a component in the vehicle. If the vehicle is operating on a smart highway, for example, the pending component failure information may also be communicated to a highway control system and/or to other vehicles in the vicinity so that an orderly exiting of the vehicle from the smart highway can be facilitated. FIG. 4 also contains the names of the sensors shown numbered in FIG. 3. Sensor 1 is a crash sensor having an accelerometer (alternately one or more dedicated accelerometers 31 can be used), sensor 2 is represents one or more microphones, sensor 3 is a coolant thermometer, sensor 904 is an oil pressure sensor, sensor 5 is an oil level sensor, sensor 6 is an air flow meter, sensor 7 is a voltmeter, sensor 8 is an ammeter, sensor 9 is a humidity sensor, sensor 10 is an engine knock sensor, sensor 11 is an oil turbidity sensor, sensor 12 is a throttle position sensor, sensor 13 is a steering torque sensor, sensor 14 is a wheel speed sensor, sensor 15 is a tachometer, sensor 16 is a speedometer, sensor 17 is an oxygen sensor, sensor 18 is a pitch/roll sensor, sensor 19 is a clock, sensor 20 is an odometer, sensor 21 is a power steering pressure sensor, sensor 22 is a pollution sensor, sensor 23 is a fuel gauge, sensor 24 is a cabin thermometer, sensor 25 is a transmission fluid level sensor, sensor 26 is a yaw sensor, sensor 27 is a coolant level sensor, sensor 28 is a transmission fluid turbidity sensor, sensor 29 is brake pressure sensor and sensor 30 is a coolant pressure sensor. Other possible sensors include a temperature transducer, a pressure transducer, a liquid level sensor, a flow meter, a position sensor, a velocity sensor, a RPM sensor, a chemical sensor and an angle sensor, angular rate sensor or gyroscope. If a distributed group of acceleration sensors or accelerometers are used to permit a determination of the location of a vibration source, the same group can, in some cases, also be used to measure the pitch, yaw and/or roll of the vehicle eliminating the need for dedicated angular rate sensors. In addition, as mentioned above, such a suite of sensors can also be used to determine the location and severity of a vehicle crash and additionally to determine that the vehicle is on the verge of rolling over. Thus, the same suite of accelerometers optimally performs a variety of functions including inertial navigation, crash sensing, vehicle diagnostics, roll-over sensing etc. Consider now some examples. The following is a partial list of potential component failures and the sensors from the list on FIG. 4 that might provide information to predict the failure of the component: Out of balance tires 1, 13, 14, 15, 20, 21 Front end out of alignment 1, 13, 21, 26 Tune up required 1, 3, 10, 12, 15, 17, 20, 22 Oil change needed 3, 4, 5, 11 Motor failure 1, 2, 3, 4, 5, 6, 10, 12, 15, 17, 22 Low tire pressure 1, 13, 14, 15, 20, 21 Front end looseness 1, 13, 16, 21, 26 Cooling system failure 3, 15, 24, 27, 30 Alternator problems 1, 2, 7, 8, 15, 19, 20 Transmission problems 1, 3, 12, 15, 16, 20, 25, 28 Differential problems 1, 12, 14 Brakes 1, 2, 14, 18, 20, 26, 29 Catalytic converter and muffler 1, 2, 12, 15, 22 Ignition 1, 2, 7, 8, 9, 10, 12, 17, 23 Tire wear 1, 13, 14, 15, 18, 20, 21, 26 Fuel leakage 20, 23 Fan belt slippage 1, 2, 3, 7, 8, 12, 15, 19, 20 Alternator deterioration 1, 2, 7, 8, 15, 19 Coolant pump failure 1, 2, 3, 24, 27, 30 Coolant hose failure 1, 2, 3, 27, 30 Starter failure 1, 2, 7, 8, 9, 12, 15 Dirty air filter 2, 3, 6, 11, 12, 17, 22 Several interesting facts can be deduced from a review of the above list. First, all of the failure modes listed can be at least partially sensed by multiple sensors. In many cases, some of the sensors merely add information to aid in the interpretation of signals received from other sensors. In today's automobile, there are few if any cases where multiple sensors are used to diagnose or predict a problem. In fact, there is virtually no failure prediction undertaken at all. Second, many of the failure modes listed require information from more than one sensor. Third, information for many of the failure modes listed cannot be obtained by observing one data point in time as is now done by most vehicle sensors. Usually an analysis of the variation in a parameter as a function of time is necessary. In fact, the association of data with time to create a temporal pattern for use in diagnosing component failures in automobile is believed to be unique to this invention as in the combination of several such temporal patterns. Fourth, the vibration measuring capability of the airbag crash sensor, or other accelerometer, is useful for most of the cases discussed above yet there is no such current use of accelerometers. The airbag crash sensor is used only to detect crashes of the vehicle. Fifth, the second most used sensor in the above list, a microphone, does not currently appear on any automobiles, yet sound is the signal most often used by vehicle operators and mechanics to diagnose vehicle problems. Another sensor that is listed above which also does not currently appear on automobiles is a pollution sensor. This is typically a chemical sensor mounted in the exhaust system for detecting emissions from the vehicle. It is expected that this and other chemical sensors will be used more in the future. In addition, from the foregoing depiction of different sensors which receive signals from a plurality of components, it is possible for a single sensor to receive and output signals from a plurality of components which are then analyzed by the processor to determine if any one of the components for which the received signals were obtained by that sensor is operating in an abnormal state. Likewise, it is also possible to provide for a plurality of sensors each receiving a different signal related to a specific component which are then analyzed by the processor to determine if that component is operating in an abnormal state. Neural networks can simultaneously analyze data from multiple sensors of the same type or different types. As can be appreciated from the above discussion, the invention described herein brings several new improvements to vehicles including, but not limited to, the use of pattern recognition technologies to diagnose potential vehicle component failures, the use of trainable systems thereby eliminating the need of complex and extensive programming, the simultaneous use of multiple sensors to monitor a particular component, the use of a single sensor to monitor the operation of many vehicle components, the monitoring of vehicle components which have no dedicated sensors, and the notification of both the driver and possibly an outside entity of a potential component failure prior to failure so that the expected failure can be averted and vehicle breakdowns substantially eliminated. Additionally, improvements to the vehicle stability, crash avoidance, crash anticipation and occupant protection are available. To implement a component diagnostic system for diagnosing the component utilizing a plurality of sensors not directly associated with the component, i.e., independent of the component, a series of tests are conducted. For each test, the signals received from the sensors are input into a pattern recognition training algorithm with an indication of whether the component is operating normally or abnormally (the component being intentionally altered to provide for abnormal operation). The data from the test are used to generate the pattern recognition algorithm, e.g., neural network, so that in use, the data from the sensors is input into the algorithm and the algorithm provides an indication of abnormal or normal operation of the component. Also, to provide a more versatile diagnostic module for use in conjunction with diagnosing abnormal operation of multiple components, tests may be conducted in which each component is operated abnormally while the other components are operating normally, as well as tests in which two or more components are operating abnormally. In this manner, the diagnostic module may be able to determine based on one set of signals from the sensors during use that either a single component or multiple components are operating abnormally. Furthermore, the pattern recognition algorithm may be trained based on patterns within the signals from the sensors. Thus, by means of a single sensor, it would be possible to determine whether one or more components are operating abnormally. To obtain such a pattern recognition algorithm, tests are conducted using a single sensor, such as a microphone, and causing abnormal operation of one or more components, each component operating abnormally while the other components operate normally and multiple components operating abnormally. In this manner, in use, the pattern recognition algorithm may analyze a signal from a single sensor and determine abnormal operation of one or more components. Note that in some cases, simulations can be used to analytically generate the relevant data. The discussion above has centered mainly on the blind training of a pattern recognition system, such as a neural network, so that faults can be discovered and failures forecast before they happen. Naturally, the diagnostic algorithms do not have to start out being totally dumb and in fact, the physics or structure of the systems being monitored can be appropriately used to help structure or derive the diagnostic algorithms. Such a system is described in a recent article “Immobots Take Control”, MIT Technology Review December, 2002. Also, of course, it is contemplated that once a potential failure has been diagnosed, the diagnostic system can in some cases act to change the operation of various systems in the vehicle to prolong the time of a failing component before the failure or in some rare cases, the situation causing the failure might be corrected. An example of the first case is where the alternator is failing and various systems or components can be turned off to conserve battery power and an example of the second case is rollover of a vehicle may be preventable through the proper application of steering torque and wheel braking force. Such algorithms can be based on pattern recognition or on models, as described in the Immobot article referenced above, or a combination thereof and all such systems are contemplated by the invention described herein. 1.3 SAW and Other Wireless Sensors in General Many sensors are now in vehicles and many more will be installed in vehicles. The following disclosure is primarily concerned with wireless sensors based on MEMS and in particular SAW technologies. Vehicle sensors include tire pressure, temperature and acceleration monitoring sensors; weight or load measuring sensors; switches; vehicle temperature, acceleration, angular position, angular rate, angular acceleration sensors; proximity; rollover; occupant presence; humidity; presence of fluids or gases; strain; road condition and friction, chemical sensors and other similar sensors providing information to a vehicle system, vehicle operator or external site. The sensors can provide information about the vehicle and/or its interior or exterior environment, about individual components, systems, vehicle occupants, subsystems, and/or about the roadway, ambient atmosphere, travel conditions and external objects. For wireless sensors, one or more interrogators can be used each having one or more antennas that transmit radio frequency energy to the sensors and receive modulated radio frequency signals from the sensors containing sensor and/or identification information. One interrogator can be used for sensing multiple switches or other devices. For example, an interrogator may transmit a chirp form of energy at 905 MHz to 925 MHz to a variety of sensors located within and/or in the vicinity of the vehicle. These sensors may be of the RFID electronic type or of the surface acoustic wave (SAW) type. In the electronic type, information can be returned immediately to the interrogator in the form of a modulated backscatter RF signal. In the case of SAW devices, the information can be returned after a delay. RFID tags may also exhibit a delay due to the charging of the capacitor. Naturally, one sensor can respond in both the electronic (either RFID or backscatter) and SAW delayed modes. When multiple sensors are interrogated using the same technology, the returned signals from the various sensors can be time, code, space or frequency multiplexed. For example, for the case of the SAW technology, each sensor can be provided with a different delay. Alternately, each sensor can be designed to respond only to a single frequency or several frequencies. The radio frequency can be amplitude, code or frequency modulated. Space multiplexing can be achieved through the use of two or more antennas and correlating the received signals to isolate signals based on direction. In many cases, the sensors will respond with an identification signal followed by or preceded by information relating to the sensed value, state and/or property. In the case of a SAW-based switch, for example, the returned signal may indicate that the switch is either on or off or, in some cases, an intermediate state can be provided signifying that a light should be dimmed, rather than or on or off, for example. SAW devices have been used for sensing many parameters including devices for chemical sensing and materials characterization in both the gas and liquid phase. They also are used for measuring pressure, strain, temperature, acceleration, angular rate and other physical states of the environment. Economies are achieved by using a single interrogator or even a small number of interrogators to interrogate many types of devices. For example, a single interrogator may monitor tire pressure and temperature, the weight of an occupying item of the seat, the position of the seat and seatback, as well as a variety of switches controlling windows, door locks, seat position, etc. in a vehicle. Such an interrogator may use one or multiple antennas and when multiple antennas are used, may switch between the antennas depending on what is being monitored. Similarly, the same or a different interrogator can be used to monitor various components of the vehicle's safety system including occupant position sensors, vehicle acceleration sensors, vehicle angular position, velocity and acceleration sensors, related to both frontal, side or rear impacts as well as rollover conditions. The interrogator could also be used in conjunction with other detection devices such as weight sensors, temperature sensors, accelerometers which are associated with various systems in the vehicle to enable such systems to be controlled or affected based on the measured state. Some specific examples of the use of interrogators and responsive devices will now be described. The antennas used for interrogating the vehicle tire pressure transducers can be located outside of the vehicle passenger compartment. For many other transducers to be sensed the antennas can be located at various positions within passenger compartment. This invention contemplates, therefore, a series of different antenna systems, which can be electronically switched by the interrogator circuitry. Alternately, in some cases, all of the antennas can be left connected and total transmitted power increased. There are several applications for weight or load measuring devices in a vehicle including the vehicle suspension system and seat weight sensors for use with automobile safety systems. As described in U.S. Pat. No. 4,096,740, U.S. Pat. No. 4,623,813, U.S. Pat. No. 5,585,571, U.S. Pat. No. 5,663,531, U.S. Pat. No. 5,821,425 and U.S. Pat. No. 5,910,647 and International Publication No. WO 00/65320(A1), SAW devices are appropriate candidates for such weight measurement systems. In this case, the surface acoustic wave on the lithium niobate, or other piezoelectric material, is modified in delay time, resonant frequency, amplitude and/or phase based on strain of the member upon which the SAW device is mounted. For example, the conventional bolt that is typically used to connect the passenger seat to the seat adjustment slide mechanism can be replaced with a stud which is threaded on both ends. A SAW or other strain device can be mounted to the center unthreaded section of the stud and the stud can be attached to both the seat and the slide mechanism using appropriate threaded nuts. Based on the particular geometry of the SAW device used, the stud can result in as little as a 3 mm upward displacement of the seat compared to a normal bolt mounting system. No wires are required to attach the SAW device to the stud. In use, the interrogator transmits a radio frequency pulse at, for example, 925 MHz that excites antenna on the SAW strain measuring system. After a delay caused by the time required for the wave to travel the length of the SAW device, a modified wave is re-transmitted to the interrogator providing an indication of the strain of the stud with the weight of an object occupying the seat corresponding to the strain. For a seat that is normally bolted to the slide mechanism with four bolts, at least four SAW strain sensors could be used. Since the individual SAW devices are very small, multiple devices can be placed on a stud to provide multiple redundant measurements, or permit bending and twisting strains to be determined, and/or to permit the stud to be arbitrarily located with at least one SAW device always within direct view of the interrogator antenna. In some cases, the bolt or stud will be made on non-conductive material to limit the blockage of the RF signal. In other cases, it will be insulated from the slide (mechanism) and used as an antenna. If two longitudinally spaced apart antennas are used to receive the SAW transmissions from the seat weight sensors, one antenna in front of the seat and the other behind the seat, then the position of the seat can be determined eliminating the need for current seat position sensors. A similar system can be used for other seat and seatback position measurements. For strain gage weight sensing, the frequency of interrogation can be considerably higher than that of the tire monitor, for example. However, if the seat is unoccupied, then the frequency of interrogation can be substantially reduced. For an occupied seat, information as to the identity and/or category and position of an occupying item of the seat can be obtained through the multiple weight sensors described. For this reason, and due to the fact that during the pre-crash event, the position of an occupying item of the seat may be changing rapidly, interrogations as frequently as once every 10 milliseconds can be desirable. This would also enable a distribution of the weight being applied to the seat to be obtained which provides an estimation of the position of the object occupying the seat. Using pattern recognition technology, e.g., a trained neural network, sensor fusion, fuzzy logic, etc., the identification of the object can be ascertained based on the determined weight and/or determined weight distribution. There are many other methods by which SAW devices can be used to determine the weight and/or weight distribution of an occupying item other than the method described above and all such uses of SAW strain sensors for determining the weight and weight distribution of an occupant are contemplated. For example, SAW devices with appropriate straps can be used to measure the deflection of the seat cushion top or bottom caused by an occupying item, or if placed on the seat belts, the load on the belts can determined wirelessly and powerlessly. Geometries similar to those disclosed in U.S. Pat. No. 6,242,701 (which discloses multiple strain gage geometries) using SAW strain-measuring devices can also be constructed, e.g., any of the multiple strain gage geometries shown therein. Although a preferred method for using the invention is to interrogate each of the SAW devices using wireless mechanisms, in some cases, it may be desirable to supply power to and/or obtain information from one or more of the SAW devices using wires. As such, the wires would be an optional feature. One advantage of the weight sensors of this invention along with the geometries disclosed in the '701 patent and herein below, is that in addition to the axial stress in the seat support, the bending moments in the structure can be readily determined. For example, if a seat is supported by four “legs”, it is possible to determine the state of stress, assuming that axial twisting can be ignored, using four strain gages on each leg support for a total of 16 such gages. If the seat is supported by three legs, then this can be reduced to 12 gages. Naturally, a three-legged support is preferable to four since with four legs, the seat support is over-determined which severely complicates the determination of the stress caused by an object on the seat. Even with three supports, stresses can be introduced depending on the nature of the support at the seat rails or other floor-mounted supporting structure. If simple supports are used that do not introduce bending moments into the structure, then the number of gages per seat can be reduced to three, provided a good model of the seat structure is available. Unfortunately, this is usually not the case and most seats have four supports and the attachments to the vehicle not only introduce bending moments into the structure but these moments vary from one position to another and with temperature. The SAW strain gages of this invention lend themselves to the placement of multiple gages onto each support as needed to approximately determine the state of stress and thus the weight of the occupant depending on the particular vehicle application. Furthermore, the wireless nature of these gages greatly simplifies the placement of such gages at those locations that are most appropriate. One additional point should be mentioned. In many cases, the determination of the weight of an occupant from the static strain gage readings yields inaccurate results due to the indeterminate stress state in the support structure. However, the dynamic stresses to a first order are independent of the residual stress state. Thus, the change in stress that occurs as a vehicle travels down a roadway caused by dips in the roadway can provide an accurate measurement of the weight of an object in a seat. This is especially true if an accelerometer is used to measure the vertical excitation provided to the seat. Some vehicle models provide load leveling and ride control functions that depend on the magnitude and distribution of load carried by the vehicle suspension. Frequently, wire strain gage technology is used for these functions. That is, the wire strain gages are used to sense the load and/or load distribution of the vehicle on the vehicle suspension system. Such strain gages can be advantageously replaced with strain gages based on SAW technology with the significant advantages in terms of cost, wireless monitoring, dynamic range, and signal level. In addition, SAW strain gage systems can be significantly more accurate than wire strain gage systems. A strain detector in accordance with this invention can convert mechanical strain to variations in electrical signal frequency with a large dynamic range and high accuracy even for very small displacements. The frequency variation is produced through use of a surface acoustic wave delay line as the frequency control element of an oscillator. A surface acoustic wave delay line comprises a transducer deposited on a piezoelectric material such as quartz or lithium niobate which is arranged so as to be deformed by strain in the member which is to be monitored. Deformation of the piezoelectric substrate changes the frequency control characteristics of the surface acoustic wave delay line, thereby changing the frequency of the oscillator. Consequently, the oscillator frequency change is a measure of the strain in the member being monitored and thus the weight applied to the seat. A SAW strain transducer is capable of a degree of accuracy substantially greater than that of a conventional resistive strain gage. Other applications of weight measuring systems for an automobile include measuring the weight of the fuel tank or other containers of fluid to determine the quantity of fluid contained therein. One problem with SAW devices is that if they are designed to operate at the GHz frequency, the feature sizes become exceeding small and the devices are difficult to manufacture. On the other hand, if the frequencies are considerably lower, for example, in the tens of megahertz range, then the antenna sizes become excessive. It is also more difficult to obtain antenna gain at the lower frequencies. This is also related to antenna size. One method of solving this problem is to transmit an interrogation signal in the high GHz range which is modulated at the hundred MHz range. At the SAW transducer, the transducer is tuned to the modulated frequency. Using a nonlinear device such as a Shocky diode, the modified signal can be mixed with the incoming high frequency signal and re-transmitted through the same antenna. For this case, the interrogator could continuously broadcast the carrier frequency. Devices based on RFID or SAW technology can be used as switches in a vehicle as described in U.S. Pat. No. 6,078,252 and U.S. Pat. No. 6,144,288, and U.S. provisional patent application Ser. No. 60/231,378. There are many ways that it can be accomplished. A switch can be used to connect an antenna to either an RFID electronic device or to a SAW device. This of course requires contacts to be closed by the switch activation. An alternate approach is to use pressure from an occupant's finger, for example, to alter the properties of the acoustic wave on the SAW material much as in a SAW touch screen. The properties that can be modified include the amplitude of the acoustic wave, and its phase, and/or the time delay or an external impedance connected to one of the SAW reflectors as disclosed in U.S. Pat. No. 6,084,503, incorporated by reference herein. In this implementation, the SAW transducer can contain two sections, one which is modified by the occupant and the other which serves as a reference. A combined signal is sent to the interrogator that decodes the signal to determine that the switch has been activated. By any of these technologies, switches can be arbitrarily placed within the interior of an automobile, for example, without the need for wires. Since wires and connectors are the clause of most warranty repairs in an automobile, not only is the cost of switches substantially reduced but also the reliability of the vehicle electrical system is substantially improved. The interrogation of switches can take place with moderate frequency such as once every 100 milliseconds. Either through the use of different frequencies or different delays, a large number of switches can be either time, code, space or frequency multiplexed to permit separation of the signals obtained by the interrogator. Another approach is to attach a variable impedance device across one of the reflectors on the SAW device. The impedance can therefore used to determine the relative reflection from the reflector compared to other reflectors on the SAW device. In this manner, the magnitude as well as the presence of a force exerted by an occupant's finger, for example, can be used to provide a rate sensitivity to the desired function. In an alternate design, as shown U.S. Pat. No. 6,144,288, the switch is used to connect the antenna to the SAW device. Of course, in this case, the interrogator will not get a return from the SAW switch unless it is depressed. Temperature measurement is another field in which SAW technology can be applied and the invention encompasses several embodiments of SAW temperature sensors. U.S. Pat. No. 4,249,418 is one of many examples of prior art SAW temperature sensors. Temperature sensors are commonly used within vehicles and many more applications might exist if a low cost wireless temperature sensor is available such as disclosed herein. The SAW technology can be used for such temperature sensing tasks. These tasks include measuring the vehicle coolant temperature, air temperature within passenger compartment at multiple locations, seat temperature for use in conjunction with seat warming and cooling systems, outside temperatures and perhaps tire surface temperatures to provide early warning to operators of road freezing conditions. One example, is to provide air temperature sensors in the passenger compartment in the vicinity of ultrasonic transducers used in occupant sensing systems as described in the current assignee's U.S. Pat. No. 5,943,295 (Varga et al.), since the speed of sound in the air varies by approximately 20% from −40° C. to 85° C. Current ultrasonic occupant sensor systems do not measure or compensate for this change in the speed of sound with the effect of significantly reducing the accuracy of the systems at the temperature extremes. Through the judicious placement of SAW temperature sensors in the vehicle, the passenger compartment air temperature can be accurately estimated and the information provided wirelessly to the ultrasonic occupant sensor system thereby permitting corrections to be made for the change in the speed of sound. Since the road can be either a source or a sink of thermal energy, strategically placed sensors that measure the surface temperature of a tire can also be used to provide an estimate of road temperature. Acceleration sensing is another field in which SAW technology can be applied and the invention encompasses several embodiments of SAW accelerometers. U.S. Pat. No. 4,199,990, U.S. Pat. No. 4,306,456 and U.S. Pat. No. 4,549,436 are examples of prior art SAW accelerometers. Most airbag crash sensors for determining whether the vehicle is experiencing a frontal or side impact currently use micromachined accelerometers. These accelerometers are usually based on the deflection of a mass which is sensed using either capacitive or piezoresistive technologies. SAW technology has previously not been used as a vehicle accelerometer or for vehicle crash sensing. Due to the importance of this function, at least one interrogator could be dedicated to this critical function. Acceleration signals from the crash sensors should be reported at least preferably every 100 microseconds. In this case, the dedicated interrogator would send an interrogation pulse to all crash sensor accelerometers every 100 microseconds and receive staggered acceleration responses from each of the SAW accelerometers wirelessly. This technology permits the placement of multiple low-cost accelerometers at ideal locations for crash sensing including inside the vehicle side doors, in the passenger compartment and in the frontal crush zone. Additionally, crash sensors can now be located in the rear of the vehicle in the crush zone to sense rear impacts. Since the acceleration data is transmitted wirelessly, concern about the detachment or cutting of wires from the sensors disappears. One of the main concerns, for example, of placing crash sensors in the vehicle doors where they most appropriately can sense vehicle side impacts, is the fear that an impact into the A-pillar of the automobile would sever the wires from the door-mounted crash sensor before the crash was sensed. This problem disappears with the current wireless technology of this invention. If two accelerometers are placed at some distance from each other, the roll acceleration of the vehicle can be determined and thus the tendency of the vehicle to rollover can be predicted in time to automatically take corrective action and/or deploy a curtain airbag or other airbag(s). Although the sensitivity of measurement is considerably greater than that obtained with conventional piezoelectric accelerometers, the frequency deviation of SAW devices remains low (in absolute value). Accordingly, the frequency drift of thermal origin should be made as low as possible by selecting a suitable cut of the piezoelectric material. The resulting accuracy is impressive as presented in U.S. Pat. No. 4,549,436, incorporated by reference herein, which discloses an angular accelerometer with a dynamic a range of I million, temperature coefficient of 0.005%/deg F., an accuracy of 1 microradian/sec2, a power consumption of 1 milliwatt, a drift of 0.01% per year, a volume of 1 cc/axis and a frequency response of 0 to 1000 Hz. The subject matter of the '436 patent is hereby included in the invention to constitute a part of the invention. A similar design can be used for acceleration sensing. In a similar manner as the polymer-coated SAW device is used to measure pressure, a device wherein a seismic mass is attached to a SAW device through a polymer interface can be made to sense acceleration. This geometry has a particular advantage for sensing accelerations below 1 G, which has proved to be very difficult for conventional micro-machined accelerometers due to their inability to both measure low accelerations and withstand shocks. Gyroscopes are another field in which SAW technology can be applied and the inventions herein encompass several embodiments of SAW gyroscopes. SAW technology is particularly applicable for gyroscopes as described in International Publication No. WO 00/79217A2 to Varadan et al. The output of such gyroscopes can be determined with an interrogator that is also used for the crash sensor accelerometers, or a dedicated interrogator can be used. Gyroscopes having an accuracy of approximately 1 degree per second have many applications in a vehicle including skid control and other dynamic stability functions. Additionally, gyroscopes of similar accuracy can be used to sense impending vehicle rollover situations in time to take corrective action. SAW gyroscopes of the type described in WO 00/79217A2 have the capability of achieving accuracies approaching about 3 degrees per hour. This high accuracy permits use of such gyroscopes in an inertial measuring unit (IMU) that can be used with accurate vehicle navigation systems and autonomous vehicle control based on differential GPS corrections. Such a system is described in U.S. Pat. No. 6,370,475. Such navigation systems depend on the availability of four or more GPS satellites and an accurate differential correction signal such as provided by the OmniStar Corporation or NASA or through the National Differential GPS system now being deployed. The availability of these signals degrades in urban canyon environments, in tunnels and on highways when the vehicle is in the vicinity of large trucks. For this application, an IMU system should be able to accurately control the vehicle for perhaps 15 seconds and preferably for up to five minutes. IMUs based on SAW technology or the technology of U.S. Pat. No. 4,549,436 discussed above are the best-known devices capable of providing sufficient accuracies for this application at a reasonable cost. Other accurate gyroscope technologies such as fiber optic systems are more accurate but can be cost-prohibitive, although recent analysis by the current assignee indicates that such gyroscopes can eventually be made cost-competitive. In high volume production, an IMU of the required accuracy based on SAW technology is estimated to cost less than about $100. Once an IMU of the accuracy described above is available in the vehicle, this same device can be used to provide significant improvements to vehicle stability control and rollover prediction systems. Keyless entry systems are another field in which SAW technology can be applied and the invention encompasses several embodiments of access control systems using SAW devices. A common use of SAW technology is for access control to buildings. RFID technology using electronics is also applicable for this purpose; however, the range of electronic RFID technology is usually limited to one meter or less. In contrast, the SAW technology, particularly when boosted, can permit sensing up to about 30 meters. As a keyless entry system, an automobile can be configured such that the doors unlock as the holder of a card containing the SAW ID system approaches the vehicle and similarly, the vehicle doors can be automatically locked when the occupant with the card travels beyond a certain distance from the vehicle. When the occupant enters the vehicle, the doors can again automatically lock either through logic or through a current system wherein doors automatically lock when the vehicle is placed in gear. An occupant with such a card would also not need to have an ignition key. The vehicle would recognize that the SAW-based card was inside vehicle and then permit the vehicle to be started by issuing an oral command if a voice recognition system is present or by depressing a button, for example, without the need for an ignition key. Although they will not be discussed in detail, SAW sensors operating in the wireless mode can also be used to sense for ice on the windshield or other exterior surfaces of the vehicle, condensation on the inside of the windshield or other interior surfaces, rain sensing, heat-load sensing and many other automotive sensing functions. They can also be used to sense outside environmental properties and states including temperature, humidity, etc. SAW sensors can be economically used to measure the temperature and humidity at numerous places both inside and outside of a vehicle. When used to measure humidity inside the vehicle, a source of water vapor can be activated to increase the humidity when desirable and the air conditioning system can be activated to reduce the humidity when necessary. Temperature and humidity measurements outside of the vehicle can be an indication of potential road icing problems. Such information can be used to provide early warning to a driver of potentially dangerous conditions. Although the invention described herein is related to land vehicles, many of these advances are equally applicable to other vehicles such as boats, airplanes and even, in some cases, homes and buildings. The invention disclosed herein, therefore, is not limited to automobiles or other land vehicles. Road condition sensing is another field in which SAW technology can be applied and the invention encompasses several embodiments of SAW road condition sensors. The temperature and moisture content of the surface of a roadway are critical parameters in determining the icing state of the roadway. Attempts have been made to measure the coefficient of friction between a tire and the roadway by placing strain gages in the tire tread. Naturally, such strain gages are ideal for the application of SAW technology especially since they can be interrogated wirelessly from a distance and they require no power for operation. As discussed herein, SAW accelerometers can also perform this function. The measurement of the friction coefficient, however, is not predictive and the vehicle operator is only able to ascertain the condition after the fact. Boosted SAW based transducers have the capability of being interrogated as much as 100 feet from the interrogator. Therefore, the judicious placement of low-cost powerless SAW temperature and humidity sensors in and/or on the roadway at critical positions can provide an advance warning to vehicle operators that the road ahead is slippery. Such devices are very inexpensive and therefore could be placed at frequent intervals along a highway. An infrared sensor that looks down the highway in front of the vehicle can actually measure the road temperature prior to the vehicle traveling on that part of the roadway. This system also would not give sufficient warning if the operator waited for the occurrence of a frozen roadway. The probability of the roadway becoming frozen, on the other hand, can be predicted long before it occurs, in most cases, by watching the trend in the temperature. Once vehicle-to-vehicle communications are common, roadway icing conditions can be communicated between vehicles. Some lateral control of the vehicle can also be obtained from SAW transducers or electronic RFID tags placed down the center of the lane, either above the vehicles and/or in the roadway, for example. A vehicle having two receiving antennas approaching such devices, through triangulation, is able to determine the lateral location of the vehicle relative to these SAW devices. If the vehicle also has an accurate map of the roadway, the identification number associated with each such device can be used to obtain highly accurate longitudinal position determinations. Ultimately, the SAW devices can be placed on structures beside the road and perhaps on every mile or tenth of a mile marker. If three antennas are used, as discussed herein, the distances from the vehicle to the SAW device can be determined. Electronic RFID tags are also suitable for lateral and longitudinal positioning purposes, however, the range available for current electronic RFID systems can be less than that of SAW-based systems. On the other hand, as disclosed in U.S. provisional patent application Ser. No. 60/231,378, the time-of-flight of the RFID system can be used to determine the distance from the vehicle to the RFID tag. Because of the inherent delay in the SAW devices and its variation with temperature, accurate distance measurement is probably not practical based on time-of-flight but somewhat less accurate distance measurements based on relative time-of-arrival can be made. Even if the exact delay imposed by the SAW device was accurately known at one temperature, such devices are usually reasonably sensitive to changes in temperature, hence they make good temperature sensors, and thus the accuracy of the delay in the SAW device is more difficult to maintain. An interesting variation of an electronic RFID that is particularly applicable to this and other applications of this invention is described in A. Pohl, L. Reindl, “New passive sensors”, Proc. 16th IEEE Instrumentation and Measurement Technology Conf., IMTC/99, 1999, pp. 1251-1255, which is incorporated by reference herein in its entirety. Many SAW devices are based on lithium niobate or similar strong piezoelectric materials. Such materials have high thermal expansion coefficients. An alternate material is quartz that has a very low thermal expansion coefficient. However, its piezoelectric properties are inferior to lithium niobate. One solution to this problem is to use lithium niobate as the coupling system between the antenna and the material or substrate upon which the surface acoustic wave travels. In this manner, the advantages of a low thermal expansion coefficient material can be obtained while using the lithium niobate for its strong piezoelectric properties. Other useful materials such as Langasite™ have properties that are intermediate between lithium niobate and quartz. The use of SAW tags as an accurate precise positioning system as described above would be applicable for accurate vehicle location, as discussed in U.S. Pat. No. 6,370,475, for lanes in tunnels, for example, or other cases where loss of satellite lock is common. The various technologies discussed above can be used in combination. The electronic RFID tag can be incorporated into a SAW tag providing a single device that provides both an instant reflection of the radio frequency waves as well as a re-transmission at a later time. This marriage of the two technologies permits the strengths of each technology to be exploited in the same device. For most of the applications described herein, the cost of mounting such a tag in a vehicle or on the roadway far exceeds the cost of the tag itself Therefore, combining the two technologies does not significantly affect the cost of implementing tags onto vehicles or roadways or side structures. A variation of this design is to use an RF circuit such as in an RFID to serve as an energy source. One design could be for the RFID to operate with directional antennas at a relatively high frequency such as 2.4 GHz. This would be primarily used to charge a capacitor to provide the energy for boosting the signal from the SAW sensor using circuitry such as a circulator discussed below. The SAW sensor could operate at a lower frequency, such as 400 MHz, permitting it to not interfere with the energy transfer to the RF circuit and also permit the signal to travel better to the receiver since it will be difficult to align the antenna at all times with the interrogator. Also, by monitoring the reception of the RF signal, the angular position of the tire can be determined and the SAW circuit designed so that it only transmits when the antennas are aligned or when the vehicle is stationary. Many other opportunities now present themselves with the RF circuit operating at a different frequency from the SAW circuit which will now be obvious to one skilled in the art. An alternate method to the electronic RFID tag is to simply use a radar reflector and measure the time-of-flight to the reflector and back. The radar reflector can even be made of a series of reflecting surfaces displaced from each other to achieve some simple coding. It should be understood that RFID antennas can be similarly configured. Another field in which SAW technology can be applied is for “ultrasound-on-a-surface” type of devices. U.S. Pat. No. 5,629,681, assigned to the current assignee herein and incorporated by reference herein, describes many uses of ultrasound in a tube. Many of the applications are also candidates for ultrasound-on-a-surface devices. In this case, a micro-machined SAW device will in general be replaced by a much larger structure. Based on the frequency and power available, and on FCC limitations, SAW devices can be designed to permit transmission distances of many feet. Since SAW devices can measure both temperature and humidity, they are also capable of monitoring road conditions in front of and around a vehicle. Thus, a properly equipped vehicle can determine the road conditions prior to entering a particular road section if such SAW devices are embedded in the road surface or on mounting structures close to the road surface as shown at 60 in FIG. 5. Such devices could provide advance warning of freezing conditions, for example. Although at 60 miles per hour, such devices may only provide a one second warning, this can be sufficient to provide information to a driver to prevent dangerous skidding. Additionally, since the actual temperature and humidity can be reported, the driver will be warned prior to freezing of the road surface. SAW device 60 is shown in detail in FIG. 5A. If a SAW device 63 is placed in a roadway, as illustrated in FIG. 6, and if a vehicle 68 has two receiving antennas 61 and 62, an interrogator can transmit a signal from either of the two antennas and at a later time, the two antennas will receive the transmitted signal from the SAW device 63. By comparing the arrival time of the two received pulses, the position of vehicle 68 on a lane of the roadway can precisely calculated. If the SAW device 63 has an identification code encoded into the returned signal generated thereby, then a processor in the vehicle 68 can determine its position on the surface of the earth, provided a precise map is available such as by being stored in the processor's memory. If another antenna 66 is provided, for example, at the rear of the vehicle 68, then the longitudinal position of the vehicle 68 can also be accurately determined as the vehicle 68 passes the SAW device 63. The SAW device 63 does not have to be in the center of the road. Alternate locations for positioning of the SAW device 63 are on overpasses above the road and on poles such as 64 and 65 on the roadside. For such cases, a source of power may be required. Such a system has an advantage over a competing system using radar and reflectors in that it is easier to measure the relative time between the two received pulses than it is to measure time-of-flight of a radar signal to a reflector and back. Such a system operates in all weather conditions and is known as a precise location system. Eventually, such a SAW device 63 can be placed every tenth of a mile along the roadway or at some other appropriate spacing. If a vehicle is being guided by a DGPS and an accurate map system such as disclosed in U.S. Pat. No. 6,405,132 is used, a problem arises when the GPS receiver system looses satellite lock as would happen when the vehicle enters a tunnel, for example. If a precise location system as described above is placed at the exit of the tunnel, then the vehicle will know exactly where it is and can re-establish satellite lock in as little as one second rather than typically 15 seconds as might otherwise be required. Other methods making use of the cell phone system can be used to establish an approximate location of the vehicle suitable for rapid acquisition of satellite lock as described in G. M. Djuknic, R. E. Richton “Geolocation and Assisted GPS”, Computer Magazine, February 2001, IEEE Computer Society, which is incorporated by reference herein in its entirety. An alternate location system is described in U.S. Pat. No. 6,480,788. More particularly, geolocation technologies that rely exclusively on wireless networks such as time of arrival, time difference of arrival, angle of arrival, timing advance, and multipath fingerprinting offer a shorter time-to-first-fix (TTFF) than GPS. They also offer quick deployment and continuous tracking capability for navigation applications, without the added complexity and cost of upgrading or replacing any existing GPS receiver in vehicles. Compared to either mobile-station-based, stand-alone GPS or network-based geolocation, assisted-GPS (AGPS) technology offers superior accuracy, availability and coverage at a reasonable cost. AGPS for use with vehicles would comprise a communications unit with a partial GPS receiver arranged in the vehicle, an AGPS server with a reference GPS receiver that can simultaneously “see” the same satellites as the communications unit and a wireless network infrastructure consisting at least of base stations and a mobile switching center. The network can accurately predict the GPS signal the communication unit will receive and convey that information to the mobile, greatly reducing search space size and shortening the TTFF from minutes to a second or less. In addition, an AGPS receiver in the communication unit can detect and demodulate weaker signals than those that conventional GPS receivers require. Because the network performs the location calculations, the communication unit only needs to contain a scaled-down GPS receiver. It is accurate within about 15 meters when they are outdoors, an order of magnitude more sensitive than conventional GPS. Since an AGPS server can obtain the vehicle's position from the mobile switching center, at least to the level of cell and sector, and at the same time monitor signals from GPS satellites seen by mobile stations, it can predict the signals received by the vehicle for any given time. Specifically, the server can predict the Doppler shift due to satellite motion of GPS signals received by the vehicle, as well as other signal parameters that are a function of the vehicle's location. In a typical sector, uncertainty in a satellite signal's predicted time of arrival at the vehicle is about ±5 μs, which corresponds to ±5 chips of the GPS coarse acquisition (C/A) code. Therefore, an AGPS server can predict the phase of the pseudorandom noise (PRN) sequence that the receiver should use to despread the C/A signal from a particular satellite—each GPS satellite transmits a unique PRN sequence used for range measurements—and communicate that prediction to the vehicle. The search space for the actual Doppler shift and PRN phase is thus greatly reduced, and the AGPS receiver can accomplish the task in a fraction of the time required by conventional GPS receivers. Further, the AGPS server maintains a connection with the vehicle receiver over the wireless link, so the requirement of asking the communication unit to make specific measurements, collect the results and communicate them back is easily met. After despreading and some additional signal processing, an AGPS receiver returns back “pseudoranges”—that is, ranges measured without taking into account the discrepancy between satellite and receiver clocks—to the AGPS server, which then calculates the vehicle's location. The vehicle can even complete the location fix itself without returning any data to the server. Sensitivity assistance, also known as modulation wipe-off, provides another enhancement to detection of GPS signals in the vehicle's receiver. The sensitivity-assistance message contains predicted data bits of the GPS navigation message, which are expected to modulate the GPS signal of specific satellites at specified times. The mobile station receiver can therefore remove bit modulation in the received GPS signal prior to coherent integration. By extending coherent integration beyond the 20-ms GPS data-bit period—to a second or more when the receiver is stationary and to 400 ms when it is fast-moving—this approach improves receiver sensitivity. Sensitivity assistance provides an additional 3-to-4-dB improvement in receiver sensitivity. Because some of the gain provided by the basic assistance—code phases and Doppler shift values—is lost when integrating the GPS receiver chain into a mobile system, this can prove crucial to making a practical receiver. Achieving optimal performance of sensitivity assistance in TIA/EIA-95 CDMA systems is relatively straightforward because base stations and mobiles synchronize with GPS time. Given that global system for mobile communication (GSM), time division multiple access (TDMA), or advanced mobile phone service (AMPS) systems do not maintain such stringent synchronization, implementation of sensitivity assistance and AGPS technology in general will require novel approaches to satisfy the timing requirement. The standardized solution for GSM and TDMA adds time calibration receivers in the field—location measurement units-that can monitor both the wireless-system timing and GPS signals used as a timing reference. Many factors affect the accuracy of geolocation technologies, especially terrain variations such as hilly versus flat and environmental differences such as urban versus suburban versus rural. Other factors, like cell size and interference, have smaller but noticeable effects. Hybrid approaches that use multiple geolocation technologies appear to be the most robust solution to problems of accuracy and coverage. AGPS provides a natural fit for hybrid solutions because it uses the wireless network to supply assistance data to GPS receivers in vehicles. This feature makes it easy to augment the assistance-data message with low-accuracy distances from receiver to base stations measured by the network equipment. Such hybrid solutions benefit from the high density of base stations in dense urban environments, which are hostile to GPS signals. Conversely, rural environments, where base stations are too scarce for network-based solutions to achieve high accuracy, provide ideal operating conditions for AGPS because GPS works well there. SAW transponders can also be placed in the license plates 67 (FIG. 6) of all vehicles at nominal cost. An appropriately equipped automobile can then determine the angular location of vehicles in its vicinity. If a third antenna 66 is placed at the center of the vehicle front, then a more accurate indication of the distance to a license plate of a preceding vehicle can also be obtained as described above. Thus, once again, a single interrogator coupled with multiple antenna systems can be used for many functions. Alternately, if more than one SAW transponder is placed spaced apart on a vehicle and if two antennas are on the other vehicle, then the direction and position of the SAW-equipped vehicle can be determined by the receiving vehicle. A general SAW temperature and pressure gage which can be wireless and powerless is shown generally at 70 located in the sidewall 73 of a fluid container 74 in FIG. 7. A pressure sensor 71 is located on the inside of the container 74, where it measures deflection of the container wall, and the fluid temperature sensor 72 on the outside. The temperature measuring SAW 70 can be covered with an insulating material to avoid the influence of the ambient temperature outside of the container 74. A SAW load sensor can also be used to measure load in the vehicle suspension system powerless and wirelessly as shown in FIG. 8. FIG. 8A illustrates a strut 75 such as either of the rear struts of the vehicle of FIG. 8. A coil spring 80 stresses in torsion as the vehicle encounters disturbances from the road and this torsion can be measured using SAW strain gages as described in U.S. Pat. No. 5,585,571 for measuring the torque in shafts. This concept is also described in U.S. Pat. No. 5,714,695. The use of SAW strain gages to measure the torsional stresses in a spring, as shown in FIG. 8B, and in particular in an automobile suspension spring has, to the knowledge of the inventors, not been heretofore disclosed. In FIG. 8B, the strain measured by SAW strain gage 78 is subtracted from the strain measured by SAW strain gage 77 to get the temperature compensated strain in spring 76. Since a portion of the dynamic load is also carried by the shock absorber, the SAW strain gages 77 and 78 will only measure the steady or average load on the vehicle. However, additional SAW strain gages 79 can be placed on a piston rod 81 of the shock absorber to obtain the dynamic load. These load measurements can then be used for active or passive vehicle damping or other stability control purposes. FIG. 9 illustrates a vehicle passenger compartment, and the engine compartment, with multiple SAW temperature sensors 85. SAW temperature sensors can be distributed throughout the passenger compartment, such as on the A-pillar, on the B-pillar, on the steering wheel, on the seat, on the ceiling, on the headliner, and on the rear glass and generally in the engine compartment. These sensors, which can be independently coded with different IDs and different delays, can provide an accurate measurement of the temperature distribution within the vehicle interior. Such a system can be used to tailor the heating and air conditioning system based on the temperature at a particular location in the passenger compartment. If this system is augmented with occupant sensors, then the temperature can be controlled based on seat occupancy and the temperature at that location. If the occupant sensor system is based on ultrasonics, then the temperature measurement system can be used to correct the ultrasonic occupant sensor system for the speed of sound within the passenger compartment. Without such a correction, the error in the sensing system can be as large as about 20 percent. In one case, the SAW temperature sensor can be made from PVDF film and incorporated within the ultrasonic transducer assembly. For the 40 kHz ultrasonic transducer case, for example, the SAW temperature sensor would return the several pulses sent to drive the ultrasonic transducer to the control circuitry using the same wires used to transmit the pulses to the transducer after a delay that is proportional to the temperature within the transducer housing. Thus, a very economical device can add this temperature sensing function using much of the same hardware that is already present for the occupant sensing system. Since the frequency is low, PVDF could be fabricated into a very low cost temperature sensor for this purpose. Other piezoelectric materials could also be used. Other sensors can be combined with the temperature sensors 85, or used separately, to measure carbon dioxide, carbon monoxide, alcohol, humidity or other desired chemicals as discussed above. The SAW temperature sensors 85 provide the temperature at their mounting location to a processor unit 83 via an interrogator with the processor unit 83 including appropriate control algorithms for controlling the heating and air conditioning system based on the detected temperatures. The processor unit 83 can control, e.g., which vents in the vehicle are open and closed, the flow rate through vents and the temperature of air passing through the vents. In general, the processor unit 83 can control whatever adjustable components are present or form part of the heating and air conditioning system. As shown in FIG. 9, a child seat 84 is present on the rear vehicle seat. The child seat 84 can be fabricated with one or more RFID tags or SAW tags (not shown). The RFID tag(s) and SAW tag(s) can be constructed to provide information on the occupancy of the child seat, i.e., whether a child is present, based on the weight. Also, the mere transmission of waves from the RFID tag(s) or SAW tag(s) on the child seat 84 would be indicative of the presence of a child seat. The RFID tag(s) and SAW tag(s) can also be constructed to provide information about the orientation of the child seat 84, i.e., whether it is facing rearward or forward. Such information about the presence and occupancy of the child seat and its orientation can be used in the control of vehicular systems, such as the vehicle airbag system. In this case, a processor would control the airbag system and would receive information from the RFID tag(s) and SAW tag(s) via an interrogator. There are many applications for which knowledge of the pitch and/or roll orientation of a vehicle or other object is desired. An accurate tilt sensor can be constructed using SAW devices. Such a sensor is illustrated in FIG. 10A and designated 86. This sensor 86 utilizes a substantially planar and rectangular mass 87 and four supporting SAW devices 88 which are sensitive to gravity. For example, the mass 87 acts to deflect a membrane on which the SAW device 88 resides thereby straining the SAW device 88. Other properties can also be used for a tilt sensor such as the direction of the earth's magnetic field. SAW devices 88 are shown arranged at the corners of the planar mass 87, but it must be understood that this arrangement is a preferred embodiment only and not intended to limit the invention. A fifth SAW device 89 can be provided to measure temperature. By comparing the outputs of the four SAW devices 88, the pitch and roll of the automobile can be measured. This sensor 86 can be used to correct errors in the SAW rate gyros described above. If the vehicle has been stationary for a period of time, the yaw SAW rate gyro can initialized to 0 and the pitch and roll SAW gyros initialized to a value determined by the tilt sensor of FIG. 10A. Many other geometries of tilt sensors utilizing one or more SAW devices are now envisioned for automotive and other applications. In particular, an alternate preferred configuration is illustrated in FIG. 10B where a triangular geometry is used. In this embodiment, the planar mass is triangular and the SAW devices 88 are arranged at the corners, although as with FIG. 10A, this is a non-limiting, preferred embodiment. Either of the SAW accelerometers described above can be utilized for crash sensors as shown in FIG. 11. These accelerometers have a substantially higher dynamic range than competing accelerometers now used for crash sensors such as those based on MEMS silicon springs and masses and others based on MEMS capacitive sensing. As discussed above, this is partially a result of the use of frequency or phase shifts which can be easily measured over a very wide range. Additionally, many conventional accelerometers that arc designed for low acceleration ranges are unable to withstand high acceleration shocks without breaking. This places practical limitations on many accelerometer designs so that the stresses in the silicon springs are not excessive. Also for capacitive accelerometers, there is a narrow limit over which distance, and thus acceleration, can be measured. The SAW accelerometer for this particular crash sensor design is housed in a container 96 which is assembled into a housing 97 and covered with a cover 98. This particular implementation shows a connector 99 indicating that this sensor would require power and the response would be provided through wires. Altemately, as discussed for other devices above, the connector 99 can be eliminated and the information and power to operate the device transmitted wirelessly. Such sensors can be used as frontal, side or rear impact sensors. They can be used in the crush zone, in the passenger compartment or any other appropriate vehicle location. If two such sensors are separated and have appropriate sensitive axes, then the angular acceleration of the vehicle can also be determined. Thus, for example, forward-facing accelerometers mounted in the vehicle side doors can be used to measure the yaw acceleration of the vehicle. Alternately, two vertical sensitive axis accelerometers in the side doors can be used to measure the roll acceleration of vehicle, which would be useful for rollover sensing. U.S. Pat. No. 6,615,656, assigned to the current assignee of this invention, provides multiple apparatus for determining the amount of liquid in a tank. Using the SAW pressure devices of this invention, multiple pressure sensors can be placed at appropriate locations within a fuel tank to measure the fluid pressure and thereby determine the quantity of fuel remaining in the tank. This is illustrated in FIG. 12. In this example, four SAW pressure transducers 100 are placed on the bottom of the fuel tank and one SAW pressure transducer 101 is placed at the top of the fuel tank to eliminate the effects of vapor pressure within tank. Using neural networks, or other pattern recognition techniques, the quantity of fuel in the tank can be accurately determined from these pressure readings in a manner similar that described the '656 patent. The SAW measuring device illustrated in FIG. 12A combines temperature and pressure measurements in a single unit using parallel paths 102 and 103 in the same manner as described above. FIG. 13A shows a schematic of a prior art airbag module deployment scheme in which sensors, which detect data for use in determining whether to deploy an airbag in the airbag module, are wired to an electronic control unit (ECU) and a command to initiate deployment of the airbag in the airbag module is sent wirelessly. By contrast, as shown in FIG. 13B, in accordance with the invention, the sensors are wireless connected to the electronic control unit and thus transmit data wirelessly. The ECU is however wired to the airbag module. SAW sensors also have applicability to various other sectors of the vehicle, including the powertrain, chassis, and occupant comfort and convenience. For example, SAW sensors have applicability to sensors for the powertrain area including oxygen sensors, gear-tooth Hall effect sensors, variable reluctance sensors, digital speed and position sensors, oil condition sensors, rotary position sensors, low pressure sensors, manifold absolute pressure/manifold air temperature (MAP/MAT) sensors, medium pressure sensors, turbo pressure sensors, knock sensors, coolant/fluid temperature sensors, and transmission temperature sensors. SAW sensors for chassis applications include gear-tooth Hall effect sensors, variable reluctance sensors, digital speed and position sensors, rotary position sensors, non-contact steering position sensors, and digital ABS (anti-lock braking system) sensors. SAW sensors for the occupant comfort and convenience area include low tire pressure sensors, HVAC temperature and humidity sensors, air temperature sensors, and oil condition sensors. SAW sensors also have applicability such areas as controlling evaporative emissions, transmission shifting, mass air flow meters, oxygen, NOx and hydrocarbon sensors. SAW based sensors are particularly useful in high temperature environments where many other technologies fail. SAW sensors can facilitate compliance with U.S. regulations concerning evaporative system monitoring in vehicles, through a SAW fuel vapor pressure and temperature sensors that measure fuel vapor pressure within the fuel tank as well as temperature. If vapors leak into the atmosphere, the pressure within the tank drops. The sensor notifies the system of a fuel vapor leak, resulting in a warning signal to the driver and/or notification to a repair facility or compliance monitoring facility. This application is particularly important since the condition within the fuel tank can be ascertained wirelessly reducing the chance of a fuel fire in an accident. The same interrogator that monitors the tire pressure SAW sensors can also monitor the fuel vapor pressure and temperature sensors resulting in significant economies. A SAW humidity sensor can be used for measuring the relative humidity and the resulting information can be input to the engine management system or the heating, ventilation and air conditioning (HVAC) system for more efficient operation. The relative humidity of the air entering an automotive engine impacts the engine's combustion efficiency; i.e., the ability of the spark plugs to ignite the fuel/air mixture in the combustion chamber at the proper time. A SAW humidity sensor in this case can measure the humidity level of the incoming engine air, helping to calculate a more precise fuel/air ratio for improved fuel economy and reduced emissions. Dew point conditions are reached when the air is fully saturated with water. When the cabin dew point temperature matches the windshield glass temperature, water from the air condenses quickly, creating frost or fog. A SAW humidity sensor with a temperature-sensing element and a window glass-temperature-sensing element can prevent the formation of visible fog formation by automatically controlling the HVAC system. FIG. 14 illustrates the placement of a variety of sensors, primarily accelerometers and/or gyroscopes, which can be used to diagnose the state of the vehicle itself. Sensor 105 can be located in the headliner or attached to the vehicle roof above the side door. Typically, there can be two such sensors one on either side of the vehicle. Sensor 106 is shown in a typical mounting location midway between the sides of the vehicle attached to or near the vehicle roof above the rear window. Sensor 109 is shown in a typical mounting location in the vehicle trunk adjacent the rear of the vehicle. Either one, two or three such sensors can be used depending on the application. If three such sensors are used, preferably one would be adjacent each side of vehicle and one in the center. Sensor 107 is shown in a typical mounting location in the vehicle door and sensor 108 is shown in a typical mounting location on the sill or floor below the door. Sensor 110, which can be also multiple sensors, is shown in a typical mounting location forward in the crush zone of the vehicle. Finally, sensor 111 can measure the acceleration of the firewall or instrument panel and is located thereon generally midway between the two sides of the vehicle. If three such sensors are used, one would be adjacent each vehicle side and one in the center. In general, sensors 105-111 provide a measurement of the state of the vehicle, such as its velocity, acceleration, angular orientation or temperature, or a state of the location at which the sensor is mounted. Thus, measurements related to the state of the sensor would include measurements of the acceleration of the sensor, measurements of the temperature of the mounting location as well as changes in the state of the sensor and rates of changes of the state of the sensor. As such, any described use or function of the sensors 105-111 above is merely exemplary and is not intended to limit the form of the sensor or its function. Each of the sensors 105-111 may be single axis, double axis or triaxial accelerometers and/or gyroscopes typically of the MEMS type. These sensors 105-111 can either be wired to the central control module or processor directly wherein they would receive power and transmit information, or they could be connected onto the vehicle bus or, in some cases, using RFID, SAW or similar technology, the sensors can be wireless and would receive their power through RF from one or more interrogators located in the vehicle. In this case, the interrogators can be connected either to the vehicle bus or directly to control module. Alternately, an inductive or capacitive power and information transfer system can be used. One particular implementation will now be described. In this case, each of the sensors 105-111 is a single or dual axis accelerometer. They are made using silicon micromachined technology such as described in U.S. Pat. No. 5,121,180 and U.S. Pat. No. 5,894,090. These are only representative patents of these devices and there exist more than 100 other relevant U.S. patents describing this technology. Commercially available MEMS gyroscopes such as from Systron Doner have accuracies of approximately one degree per second. In contrast, optical gyroscopes typically have accuracies of approximately one degree per hour. Unfortunately, the optical gyroscopes are believed to be expensive for automotive applications. However new developments by the current assignee are reducing this cost and such gyroscopes are likely to become cost effective in a few years. On the other hand, typical MEMS gyroscopes are not sufficiently accurate for many control applications. The angular rate function can be obtained through placing accelerometers at two separated, non-co-located points in a vehicle and using the differential acceleration to obtain an indication of angular motion and angular acceleration. From the variety of accelerometers shown on FIG. 14, it can be appreciated that not only will all accelerations of key parts of the vehicle be determined, but the pitch, yaw and roll angular rates can also be determined based on the accuracy of the accelerometers. By this method, low cost systems can be developed which, although not as accurate as the optical gyroscopes, are considerably more accurate than conventional MEMS gyroscopes. Alternately, it has been found that from a single package containing up to three low cost MEMS gyroscopes and three low cost MEMS accelerometers, when carefully calibrated, an accurate inertial measurement unit (IMU) can be constructed that performs as well as units costing a great deal more. Such a package is sold by Crossbow Technology, Inc. 41 Daggett Dr., San Jose, Calif. 95134. If this IMU is combined with a GPS system and sometimes other vehicle sensor inputs using a Kalman filter, accuracy approaching that of expensive military units can be achieved. Instead of using two accelerometers at separate locations on the vehicle, a single conformal MEMS-IDT gyroscope may be used. Such a conformal MEMS-IDT gyroscope is described in a paper by V. K. Karadan, Conformal MEMS-IDT Gyroscopes and Their Comparison With Fiber Optic Gyro. The MEMS-IDT gyroscope is based on the principle of surface acoustic wave (SAW) standing waves on a piezoelectric substrate. A surface acoustic wave resonator is used to create standing waves inside a cavity and the particles at the anti-nodes of the standing waves experience large amplitude of vibrations, which serves as the reference vibrating motion for the gyroscope. Arrays of metallic dots are positioned at the anti-node locations so that the effect of Coriolis force due to rotation will acoustically amplify the magnitude of the waves. Unlike other MEMS gyroscopes, the MEMS-IDT gyroscope has a planar configuration with no suspended resonating mechanical structures. Other SAW-based gyroscopes are also now under development. The system of FIG. 14 using dual axis accelerometers, or the IMU Kalman filter system, therefore provides a complete diagnostic system of the vehicle itself and its dynamic motion. Such a system is far more accurate than any system currently available in the automotive market. This system provides very accurate crash discrimination since the exact location of the crash can be determined and, coupled with knowledge of the force deflection characteristics of the vehicle at the accident impact site, an accurate determination of the crash severity and thus the need for occupant restraint deployment can be made. Similarly, the tendency of a vehicle to roll over can be predicted in advance and signals sent to the vehicle steering, braking and throttle systems to attempt to ameliorate the rollover situation or prevent it. In the event that it cannot be prevented, the deployment side curtain airbags can be initiated in a timely manner. Similarly, the tendency of the vehicle to the slide or skid can be considerably more accurately determined and again the steering, braking and throttle systems commanded to minimize the unstable vehicle behavior. Thus, through the sample deployment of inexpensive accelerometers at a variety of locations in the vehicle, or the IMU Kalman filter system significant improvements are made in vehicle stability control, crash sensing, rollover sensing and resulting occupant protection technologies. As mentioned above, the combination of the outputs from these accelerometer sensors and the output of strain gage weight sensors in a vehicle seat, or in or on a support structure of the seat, can be used to make an accurate assessment of the occupancy of the seat and differentiate between animate and inanimate occupants as well as determining where in the seat the occupants are sitting. This can be done by observing the acceleration signals from the sensors of FIG. 14 and simultaneously the dynamic strain gage measurements from seat-mounted strain gages. The accelerometers provide the input function to the seat and the strain gages measure the reaction of the occupying item to the vehicle acceleration and thereby provide a method of determining dynamically the mass of the occupying item and its location. This is particularly important during occupant position sensing during a crash event. By combining the outputs of the accelerometers and the strain gages and appropriately processing the same, the mass and weight of an object occupying the seat can be determined as well as the gross motion of such an object so that an assessment can be made as to whether the object is a life form such as a human being. For this embodiment, a sensor, not shown, that can be one or more strain gage weight sensors is mounted on the seat or in connection with the seat or its support structure. Suitable mounting locations and forms of weight sensors are discussed in the current assignee's U.S. Pat. No. 6,242,701 and contemplated for use in this invention as well. The mass or weight of the occupying item of the seat can thus be measured based on the dynamic measurement of the strain gages with optional consideration of the measurements of accelerometers on the vehicle, which are represented by any of sensors 105-111. A SAW Pressure Sensor can also be used with bladder weight sensors permitting that device to be interrogated wirelessly and without the need to supply power. Similarly, a SAW device can be used as a general switch in a vehicle and in particular as a seatbelt buckle switch indicative of seatbelt use. Such systems can be boosted as disclosed herein or not as required by the application. Both of these inventions are disclosed in patents and co-pending patent applications of the current assignee. The operating frequency of SAW devices has hereto for been limited to less that about 500 MHz due to problems in lithography resolution, which of course is constantly improving. This is related to the speed of sound in the SAW material. Diamond has the highest speed of sound and thus would be an ideal SAW material. However, diamond is not piezoelectric. This problem can be solved partially by using a combination or laminate of diamond and a piezoelectric material. Recent advances in the manufacture of diamond films that can be combined with a piezoelectric material such as lithium niobate promise to permit higher frequencies to be used since the spacing between the inter-digital transducer (IDT) fingers can be increased for a given frequency. A particularly attractive frequency is 2.4 GHz or Wi-Fi as the potential exists for the use of more sophisticated antennas such as the Yagi antenna that have more gain and directionality. In a related invention, the driver can be provided with a keyless entry device, other RFID tag, smart card or cell phone with an RF transponder, that can be powerless in the form of an RFID or similar device, which can also be boosted as described herein. The interrogator determines the proximity of the driver to the vehicle door or other similar object such as a building or house door or vehicle trunk. As shown in FIG. 15A, if a driver 118 remains within 1 meter, for example, from the door or trunk lid 116, for example, for a time period such as 5 seconds, then the door or trunk lid 116 can automatically unlock and ever open in some implementations. Thus, as the driver 118 approaches the trunk with his or her arms filled with packages 117 and pauses, the trunk can automatically open (see FIG. 15B). Such a system would be especially valuable for older people. Naturally, this system can also be used for other systems in addition to vehicle doors and trunk lids. As shown in FIG. 15C, an interrogator 96 is placed on the vehicle, e.g., in the trunk 98 as shown, and transmits waves. When the keyless entry device 100, which contains an antenna 102 and a circuit including a circulator 104 and a memory containing a unique ID code 106, is a set distance from the interrogator 96 for a certain duration of time, the interrogator 96 directs a trunk opening device 108 to open the trunk 98. A SAW device can also be used as a wireless switch as shown in FIGS. 16A and 16B. FIG. 16A shows a surface 120 containing a projection 122 on top of a SAW device 121. Surface material 120 could be, for example, the armrest of an automobile, the steering wheel airbag cover, or any other surface within the passenger compartment of an automobile or elsewhere. Projection 122 will typically be a material capable of transmitting force to the surface of SAW device 121. As shown in FIG. 16B, a projection 123 may be placed on top of the SAW device 124. This projection 123 permits force exerted on the projection 122 to create a pressure on the SAW device 124. This increased pressure changes the time delay or natural frequency of the SAW wave traveling on the surface of material. Alternately, it can affect the magnitude of the returned signal. The projection 123 is typically held slightly out of contact with the surface until forced into contact with it. An alternate approach is to place a switch across the IDT 127 as shown in FIG. 16C. If switch 125 is open, then the device will not return a signal to the interrogator. If it is closed, than the IDT 127 will act as a reflector sending a signal back to IDT 128 and thus to the interrogator. Alternately, a switch 126 can be placed across the SAW device. In this case, a switch closure shorts the SAW device and no signal is returned to the interrogator. For the embodiment of FIG. 16C, using switch 126 instead of switch 125, a standard reflector IDT would be used in place of the IDT 127. Most SAW-based accelerometers work on the principle of straining the SAW surface and thereby changing either the time delay or natural frequency of the system. An alternate novel accelerometer is illustrated FIG. 17A wherein a mass 130 is attached to a silicone rubber coating 131 which has been applied the SAW device. Acceleration of the mass in FIG. 17A in the direction of arrow X changes the amount of rubber in contact with the surface of the SAW device and thereby changes the damping, natural frequency or the time delay of the device. By this method, accurate measurements of acceleration below 1 G are readily obtained. Furthermore, this device can withstand high deceleration shocks without damage. FIG. 17B illustrates a more conventional approach where the strain in a beam 132 caused by the acceleration acting on a mass 133 is measured with a SAW strain sensor 134. It is important to note that all of these devices have a high dynamic range compared with most competitive technologies. In some cases, this dynamic range can exceed 100,000. This is the direct result of the ease with which frequency and phase can be accurately measured. A gyroscope, which is suitable for automotive applications, is illustrated in FIG. 18 and described in detail in V. K. Varadan's International Application No. WO 00/79217, which is incorporated by reference herein in its entirety. This SAW-based gyroscope has applicability for the vehicle navigation, dynamic control, and rollover sensing among others. Note that any of the disclosed applications can be interrogated by the central interrogator of this invention and can either be powered or operated powerlessly as described in general above. Block diagrams of three interrogators suitable for use in this invention are illustrated in FIGS. 19A-19C. FIG. 19A illustrates a super heterodyne circuit and FIG. 19B illustrates a dual super heterodyne circuit. FIG. 19C operates as follows. During the burst time two frequencies, F1 and F1+F2, are sent by the transmitter after being generated by mixing using oscillator Osc. The two frequencies are needed by the SAW transducer where they are mixed yielding F2 which is modulated by the SAW and contains the information. Frequency (F1+F2) is sent only during the burst time while frequency F1 remains on until the signal F2 returns from the SAW. This signal is used for mixing. The signal returned from the SAW transducer to the interrogator is F1+F2 where F2 has been modulated by the SAW transducer. It is expected that the mixing operations will result in about 12 db loss in signal strength. As discussed, theoretically a SAW can be used for any sensing function provided the surface across which the acoustic wave travels can be modified in terms of its mass, elastic properties or any property that affects the speed amplitude or damping of the surface wave. Thus, gases and vapors can be sensed through the placement of a layer on the SAW that absorbs the gas or vapor, for example. Similarly, a radiation sensor can result through the placement of a radiation sensitive coating on the surface of the SAW. Normally, a SAW device is interrogated with a constant amplitude and frequency RF pulse. This need not be the case and a modulated pulse can also be used. If for example a pseudorandom or code modulation is used, then a SAW interrogator can distinguish its communication from that of another vehicle that may be in the vicinity. This doesn't totally solve the problem of interrogating a tire that is on an adjacent vehicle but it does solve the problem of the interrogator being confused by the transmission from another interrogator. This confusion can also be partially solved if the interrogator only listens for a return signal based on when it expects that signal to be present based on when it sent the signal. That expectation can be based the physical location of the tire relative to the interrogator which is unlikely to come from a tire on an adjacent vehicle which only momentarily could be at an appropriate distance from the interrogator. The interrogator would of course need to have correlation software in order to be able to differentiate the relevant signals. The correlation technique also permits the interrogator to separate the desired signals from noise thereby improving the sensitivity of the correlator. As discussed elsewhere herein, the particular tire that is sending a signal can be determined if multiple antennas, such as three, each receive the signal. For a 500 MHz signal, for example, the wave length is about 60 cm. If the distance from a tire transmitter to each of three antennas is on the order of one meter, then the relative distance from each antenna to the transmitter can easily be determined to within a few centimeters and thus the location of the transmitter can be found by triangulation. If that location is not a possible location for a tire transmitter, then the data can be ignored thus solving the problem of a transmitter from an adjacent vehicle being read by the wrong vehicle interrogator. This will be discussed in more detail below with regard to solving the problem of a truck having 18 tires that all need to be monitored. Note also, each antenna can have associated with it some simple circuitry that permits it to receive a signal, amplify it, change its frequency and retransmit it either through a wire of through the air to the interrogator thus eliminating the need for long and expensive coax cables. U.S. Pat. No. 6,622,567 describes a peak strain RFID technology based device with the novelty being the use of a mechanical device that records the peak strain experienced by the device. Like the system of the invention herein, the system does not require a battery and receives its power from the RFID circuit. The invention described herein includes the use of RFID based sensors either in the peak strain mode or in the preferred continuous strain mode. This invention is not limited to measuring strain as SAW and RFID based sensors can be used for measuring many other parameters including chemical vapor concentration, temperature, acceleration, angular velocity etc. 1.4 Tire Monitoring Various mechanisms to monitor tires and obtain data about the properties of the tires, e.g., temperature and pressure of the air therein, are disclosed in the parent application, U.S. patent application Ser. No. 10/701,361, along with mechanisms for boosting signals from certain tire monitors and others sensors and generating energy to power such tire monitors and other sensors, and the disclosure of all of these mechanism is incorporated by reference herein. Any of these tire monitors can be provided on the vehicle and coupled to the diagnostic module so that information about the tires is obtained by the diagnostic module and used to assess potential problems with the tires and/or be conveyed to a remote service center, dealer and/or manufacturers. 1.5 Occupant Sensing Occupant presence and position sensing is another field in which SAW technology can be applied and the invention encompasses several embodiments of SAW occupant presence and/or position sensors. Many sensing systems are available for the use to identify and locate occupants or other objects in a passenger compartment of the vehicle. Such sensors include ultrasonic sensors, chemical sensors (e.g., carbon dioxide), cameras, radar systems, heat sensors, capacitance, magnetic or other field change sensors, etc. Most of these sensors require power to operate and return information to a central processor for analysis. An ultrasonic sensor, for example, may be mounted in or near the headliner of the vehicle and periodically it transmits a few ultrasonic waves and receives reflections of these waves from occupying items of the passenger seat. Current systems on the market are controlled by electronics in a dedicated ECU. FIG. 20 is a side view, with parts cutaway and removed of a vehicle showing the passenger compartment containing a rear-facing child seat 342 on a front passenger seat 343 and one mounting location for a first embodiment of a vehicle interior monitoring system in accordance with the invention. The interior monitoring system is capable of detecting the presence of an object, determining the type of object, determining the location of the object, and/or determining another property or characteristic of the object. A property of the object could be the orientation of a child seat, the velocity of an adult and the like. For example, the vehicle interior monitoring system can determine that an object is present on the seat, that the object is a child seat and that the child seat is rear-facing. The vehicle interior monitoring system could also determine that the object is an adult, that he is drunk and that he is out-of-position relative to the airbag. In this embodiment, six transducers 344, 345, 346, 347, 348 and 349 are used, although any number of transducers may be used. Each transducer 344, 345, 346, 347, 348, 349 may comprise only a transmitter which transmits energy, waves or radiation, only a receiver which receives energy, waves or radiation, both a transmitter and a receiver capable of transmitting and receiving energy, waves or radiation, an electric field sensor, a capacitive sensor, or a self-tuning antenna-based sensor, weight sensor, chemical sensor, motion sensor or vibration sensor, for example. Such transducers or receivers 344-349 may be of the type which emit or receive a continuous signal, a time varying signal (such as a capacitor or electric field sensor) or a spatial varying signal such as in a scanning system. One particular type of radiation-receiving receiver for use in the invention is a receiver capable of receiving electromagnetic waves. When ultrasonic energy is used, transducer 345 can be used as a transmitter and transducers 344,346 as receivers. Naturally, other combinations can be used such as where all transducers are transceivers (transmitters and receivers). For example, transducer 345 can be constructed to transmit ultrasonic energy toward the front passenger seat, which is modified, in this case by the occupying item of the passenger seat, i.e., the rear-facing child seat 342, and the modified waves are received by the transducers 344 and 346, for example. A more common arrangement is where transducers 344, 345 and 346 are all transceivers. Modification of the ultrasonic energy may constitute reflection of the ultrasonic energy as the ultrasonic energy is reflected back by the occupying item of the seat. The waves received by transducers 344 and 346 vary with time depending on the shape of the object occupying the passenger seat, in this case, the rear-facing child seat 342. Each object will reflect back waves having a different pattern. Also, the pattern of waves received by transducer 344 will differ from the pattern received by transducer 346 in view of its different mounting location. This difference generally permits the determination of the location of the reflecting surface (i.e., the rear-facing child seat 342) through triangulation. Through the use of two transducers 344,346, a sort of stereographic image is received by the two transducers and recorded for analysis by processor 340, which is coupled to the transducers 344,345,346. This image will differ for each object that is placed on the vehicle seat and it will also change for each position of a particular object and for each position of the vehicle seat. Elements 344,345,346, although described as transducers, are representative of any type of component used in a wave-based analysis technique. For ultrasonic systems, the “image” recorded from each ultrasonic transducer/receiver, is actually a time series of digitized data of the amplitude of the received signal versus time. Since there are two receivers, two time series are obtained which are processed by the processor 340. The processor 340 may include electronic circuitry and associated, embedded software. Processor 340 constitutes one form of a generating system in accordance with the invention which generates information about the occupancy of the passenger compartment based on the waves received by the transducers 344,345,346. When different objects are placed on the front passenger seat, the two images from transducers 344,346, for example, are different but there are also similarities between all images of rear-facing child seats, for example, regardless of where on the vehicle seat they are placed and regardless of what company manufactured the child seat. Alternately, there will be similarities between all images of people sitting on the seat regardless of what they are wearing, their age or size. The problem is to find the “rules” which differentiate the images of one type of object from the images of other types of objects, e.g., which differentiate the occupant images from the rear-facing child seat images. The similarities of these images for various child seats are frequently not obvious to a person looking at plots of the time series and thus computer algorithms are developed to sort out the various patterns. For a more detailed discussion of pattern recognition, see U.S. Pat. No. 5,943,295 to Varga et al. The determination of these rules is important to the pattern recognition techniques used in this invention. In general, three approaches have been useful, artificial intelligence, fuzzy logic and artificial neural networks (including cellular and modular or combination neural networks and support vector machines) (although additional types of pattern recognition techniques may also be used, such as sensor fusion). In some embodiments of this invention, such as the determination that there is an object in the path of a closing window as described below, the rules are sufficiently obvious that a trained researcher can sometimes look at the returned signals and devise an algorithm to make the required determinations. In others, such as the determination of the presence of a rear-facing child seat or of an occupant, artificial neural networks are used to determine the rules. One such set of neural network software for determining the pattern recognition rules is available from the NeuralWare Corporation of Pittsburgh, Pa. The system used in a preferred implementation of this invention for the determination of the presence of a rear-facing child seat, of an occupant or of an empty seat is the artificial neural network. In this case, the network operates on the two returned signals as sensed by transducers 344 and 346, for example. Through a training session, the system is taught to differentiate between the three cases. This is done by conducting a large number of experiments where all possible child seats are placed in all possible orientations on the front passenger seat. Similarly, a sufficiently large number of experiments are run with human occupants and with boxes, bags of groceries and other objects (both inanimate and animate). Sometimes, as many as 1,000,000 such experiments are run before the neural network is sufficiently trained so that it can differentiate among the three cases and output the correct decision with a very high probability. Of course, it must be realized that a neural network can also be trained to differentiate among additional cases, e.g., a forward-facing child seat. Once the network is determined, it is possible to examine the result using tools supplied by NeuralWare or International Scientific Research, for example, to determine the rules that were finally arrived at by the trial and error techniques. In that case, the rules can then be programmed into a microprocessor resulting in a fuzzy logic or other rule-based system. Alternately, a neural computer, or cellular neural network, can be used to implement the net directly. In either case, the implementation can be carried out by those skilled in the art of pattern recognition. If a microprocessor is used, a memory device is also required to store the data from the analog-to-digital converters that digitize the data from the receiving transducers. On the other hand, if a neural network computer is used, the analog signal can be fed directly from the transducers to the neural network input nodes and an intermediate memory is not required. Memory of some type is needed to store the computer programs in the case of the microprocessor system and if the neural computer is used for more than one task, a memory is needed to store the network specific values associated with each task. Electromagnetic energy-based occupant sensors exist that use many portions of the electromagnetic spectrum. A system based on the ultraviolet, visible or infrared portions of the spectrum generally operate with a transmitter and a receiver of reflected radiation. The receiver may be a camera or a photo detector such as a pin or avalanche diode as described in detail in above-referenced patents and patent applications. At other frequencies, the absorption of the electromagnetic energy is primarily and at still other frequencies, the capacitance or electric field influencing effects are used. Generally, the human body will reflect, scatter, absorb or transmit electromagnetic energy in various degrees depending on the frequency of the electromagnetic waves. All such occupant sensors are included herein. In the embodiment wherein electromagnetic energy is used, it is to be appreciated that any portion of the electromagnetic signals that impinges upon, surrounds or involves a body portion of the occupant is at least partially absorbed by the body portion. Sometimes, this is due to the fact that the human body is composed primarily of water, and that electromagnetic energy of certain frequencies is readily absorbed by water. The amount of electromagnetic signal absorption is related to the frequency of the signal, and size or bulk of the body portion that the signal impinges upon. For example, a torso of a human body tends to absorb a greater percentage of electromagnetic energy than a hand of a human body. Thus, when electromagnetic waves or energy signals are transmitted by a transmitter, the returning waves received by a receiver provide an indication of the absorption of the electromagnetic energy. That is, absorption of electromagnetic energy will vary depending on the presence or absence of a human occupant, the occupant's size, bulk, surface reflectivity, etc. depending on the frequency, so that different signals will be received relating to the degree or extent of absorption by the occupying item on the seat. The receiver will produce a signal representative of the returned waves or energy signals which will thus constitute an absorption signal as it corresponds to the absorption of electromagnetic energy by the occupying item in the seat. One or more of the transducers 344,345,346 can also be image-receiving devices, such as cameras, which take images of the interior of the passenger compartment. These images can be transmitted to a remote facility to monitor the passenger compartment or can be stored in a memory device for use in the event of an accident, i.e., to determine the status of the occupants of the vehicle prior to the accident. In this manner, it can be ascertained whether the driver was falling asleep, talking on the phone, etc. To aid in the detection of the presence of child seats as well as their orientation, a device 341 can be placed on the child seat in some convenient location where its presence can be sensed by a vehicle-mounted sensor that can be in the seat, dashboard, headliner or any other convenient location depending on the system design. The device 341 can be a reflector, resonator, RFID tag, SAW device, or any other tag or similar device that permits easy detection of its presence and perhaps its location or proximity. A memory device for storing the images of the passenger compartment, and also for receiving and storing any of the other information, parameters and variables relating to the vehicle or occupancy of the vehicle, may be in the form a standardized “black box” (instead of or in addition to a memory part in a processor 340). The IEEE Standards Association is currently beginning to develop an international standard for motor vehicle event data recorders. The information stored in the black box and/or memory unit in the processor 340, can include the images of the interior of the passenger compartment as well as the number of occupants and the health state of the occupants. The black box would preferably be tamper-proof and crash-proof and enable retrieval of the information after a crash. The use of wave-type sensors as the transducers 344,345,346 as well as electric field sensors is discussed above. Electric field sensors and wave sensors are essentially the same from the point of view of sensing the presence of an occupant in a vehicle. In both cases, a time-varying electric field is disturbed or modified by the presence of the occupant. At high frequencies in the visual, infrared and high frequency radio wave region, the sensor is based on its capability to sense change of wave characteristics of the electromagnetic field, such as amplitude, phase or frequency. As the frequency drops, other characteristics of the field are measured. At still lower frequencies, the occupant's dielectric properties modify parameters of the reactive electric field in the occupied space between/near the plates of a capacitor. In this latter case, the sensor senses the change in charge distribution on the capacitor plates by measuring, for example, the current wave magnitude or phase in the electric circuit that drives the capacitor. These measured parameters are directly connected with parameters of the displacement current in the occupied space. In all cases, the presence of the occupant reflects, absorbs or modifies the waves or variations in the electric field in the space occupied by the occupant. Thus, for the purposes of this invention, capacitance, electric field or electromagnetic wave sensors are equivalent and although they are all technically “field” sensors they will be considered as “wave” sensors herein. What follows is a discussion comparing the similarities and differences between two types of field or wave sensors, electromagnetic wave sensors and capacitive sensors as exemplified by Kithil in U.S. Pat. No. 5,702,634. An electromagnetic field disturbed or emitted by a passenger in the case of an electromagnetic wave sensor, for example, and the electric field sensor of Kithil, for example, are in many ways similar and equivalent for the purposes of this invention. The electromagnetic wave sensor is an actual electromagnetic wave sensor by definition because they sense parameters of a wave, which is a coupled pair of continuously changing electric and magnetic fields. The electric field here is not a static, potential one. It is essentially a dynamic, rotational electric field coupled with a changing magnetic one, that is, an electromagnetic wave. It cannot be produced by a steady distribution of electric charges. It is initially produced by moving electric charges in a transmitter, even if this transmitter is a passenger body for the case of a passive infrared sensor. In the Kithil sensor, a static electric field is declared as an initial material agent coupling a passenger and a sensor (see Column 5, lines 5-7): “The proximity sensor 12 each function by creating an electrostatic field between oscillator input loop 54 and detector output loop 56, which is affected by presence of a person near by, as a result of capacitive coupling, . . . ”). It is a potential, non-rotational electric field. It is not necessarily coupled with any magnetic field. It is the electric field of a capacitor. It can be produced with a steady distribution of electric charges. Thus, it is not an electromagnetic wave by definition but if the sensor is driven by a varying current, then it produces a quasistatic electric field in the space between/near the plates of the capacitor. Kithil declares that his capacitance sensor uses a static electric field. Thus, from the consideration above, one can conclude that Kithil's sensor cannot be treated as a wave sensor because there are no actual electromagnetic waves but only a static electric field of the capacitor in the sensor system. However, this is not believed to be the case. The Kithil system could not operate with a true static electric field because a steady system does not carry any information. Therefore, Kithil is forced to use an oscillator, causing an alternate current in the capacitor and a reactive quasi-static electric field in the space between the capacitor plates, and a detector to reveal an informative change of the sensor capacitance caused by the presence of an occupant (see FIG. 7 and its description). In this case, the system becomes a “wave sensor” in the sense that it starts generating actual time-varying electric field that certainly originates electromagnetic waves according to the definition above. That is, Kithil's sensor can be treated as a wave sensor regardless of the shape of the electric field that it creates a beam or a spread shape. As follows from the Kithil patent, the capacitor sensor is likely a parametric system where the capacitance of the sensor is controlled by influence of the passenger body. This influence is transferred by means of the near electromagnetic field (i.e., the wave-like process) coupling the capacitor electrodes and the body. It is important to note that the same influence takes place with a real static electric field also, that is in absence of any wave phenomenon. This would be a situation if there were no oscillator in Kithil's system. However, such a system is not workable and thus Kithil reverts to a dynamic system using time-varying electric fields. Thus, although Kithil declares the coupling is due to a static electric field, such a situation is not realized in his system because an alternating electromagnetic field (“quasi-wave”) exists in the system due to the oscillator. Thus, the sensor is actually a wave sensor, that is, it is sensitive to a change of a wave field in the vehicle compartment. This change is measured by measuring the change of its capacitance. The capacitance of the sensor system is determined by the configuration of its electrodes, one of which is a human body, that is, the passenger inside of and the part which controls the electrode configuration and hence a sensor parameter, the capacitance. The physics definition of “wave” from Webster's Encyclopedic Unabridged Dictionary is: “11. Physics. A progressive disturbance propagated from point to point in a medium or space without progress or advance of the points themselves, . . . ”. In a capacitor, the time that it takes for the disturbance (a change in voltage) to propagate through space, the dielectric and to the opposite plate is generally small and neglected but it is not zero. As the frequency driving the capacitor increases and the distance separating the plates increases, this transmission time as a percentage of the period of oscillation can become significant. Nevertheless, an observer between the plates will see the rise and fall of the electric field much like a person standing in the water of an ocean. The presence of a dielectric body between the plates causes the waves to get bigger as more electrons flow to and from the plates of the capacitor. Thus, an occupant affects the magnitude of these waves which is sensed by the capacitor circuit. The electromagnetic field is a material agent that carries information about a passenger's position in both Kithil's and a beam-type electromagnetic wave sensor. An alternate method as taught in this invention is to use an interrogator to send a signal to the headliner-mounted ultrasonic sensor causing that sensor to transmit and receive ultrasonic waves. The sensor in this case would perform mathematical operations on the received waves and create a vector of data containing perhaps twenty to forty values and transmit that vector wirelessly to the interrogator. By means of this system, the ultrasonic sensor need only be connected to the vehicle power system and the information can be transferred to and from the sensor wirelessly. Such a system significantly reduces the wiring complexity especially when there may be multiple such sensors distributed in the passenger compartment. Then, only a power wire needs to be attached to the sensor and there does not need to be any direct connection between the sensor and the control module. The same philosophy applies to radar-based sensors, electromagnetic sensors of all kinds including cameras, capacitive or other electromagnetic field change sensitive sensors etc. In some cases, the sensor itself can operate on power supplied by the interrogator through radio frequency transmission. In this case, even the connection to the power line can be omitted. This principle can be extended to the large number of sensors and actuators that are currently in the vehicle where the only wires that are needed are those to supply power to the sensors and actuators and the information is supplied wirelessly. Such wireless powerless sensors can also be use, for example, as close proximity sensors based on measurement of thermal radiation from an occupant. Such sensors can be mounted on any of the surfaces in the passenger compartment, including the seats, which are likely to receive such radiation. A significant number of people are suffocated each year in automobiles due to excessive heat, carbon dioxide, carbon monoxide, or other dangerous fumes. The SAW sensor technology is particularly applicable to solving these kinds of problems. The temperature measurement capabilities of SAW transducers have been discussed above. If the surface of a SAW device is covered with a material which captures carbon dioxide, for example, such that the mass, elastic constants or other property of surface coating changes, the characteristics of the surface acoustic waves can be modified as described in detail in U.S. Pat. No. 4,637,987 and elsewhere. Once again, an interrogator can sense the condition of these chemical-sensing sensors without the need to supply power and connect the sensors with either wireless communication or through the power wires. If a concentration of carbon monoxide is sensed, for example, an alarm can be sounded, the windows opened, and/or the engine extinguished. Similarly, if the temperature within the passenger compartment exceeds a certain level, the windows can be automatically opened a little to permit an exchange of air reducing the inside temperature and thereby perhaps saving the life of an infant or pet left in the vehicle unattended. In a similar manner, the coating of the surface wave device can contain a chemical which is responsive to the presence of alcohol. In this case, the vehicle can be prevented from operating when the concentration of alcohol vapors in the vehicle exceeds some predetermined limit. Such a device can advantageously be mounted in the headliner above the driver's seat. Each year, a number of children and animals are killed when they are locked into a vehicle trunk. Since children and animals emit significant amounts of carbon dioxide, a carbon dioxide sensor connected to the vehicle system wirelessly and powerlessly provides an economic way of detecting the presence of a life form in the trunk. If a life form is detected, then a control system can release a trunk lock thereby opening the trunk. Alarms can also be sounded or activated when a life form is detected in the trunk. An infrared sensor can perform a similar function. FIG. 21 illustrates a SAW strain gage as described above, where the tension in the seat belt 350 can be measured without the requirement of power or signal wires. FIG. 21 illustrates a powerless and wireless passive SAW strain gage-based device 357 for this purpose. There are many other places that such a device can be mounted to measure the tension in the seatbelt at one place or at multiple places. In FIG. 22, a bolt 360 is used to attach a vehicle seat to a support structure such as a slide mechanism as illustrated in FIGS. 21 and 22 in U.S. Pat. No. 6,242,701. The bolt 360 is attached to the seat or seat structure (not shown) by inserting threaded section 361 containing threads 362 and then attaching a nut (not shown) to secure the bolt 360 to the seat or seat structure. Similarly, the lower section of the bolt 360 is secured to the slide mechanism (not shown) by lower bolt portion 363 by means of a nut (not shown) engaging threads 364. Four such bolts 360 are typically used to attach the seat to the vehicle. As the weight in the seat increases, the load is transferred to the vehicle floor by means of stresses in bolts 360. The stress in the bolt section 365 is not affect by stresses in the bolt sections 361 and 363 caused by the engagement of the nuts that attach the bolts 360 to the seat and vehicle respectively. The silicon strain gage 366 is attached, structured and arranged to measure the strain in bolt section 365 caused by loading from the seat and its contents. Silicon strain gage 366 is selected for its high gage factor and low power requirements relative to other strain gage technologies. Associated electronics 367 are typically incorporated into a single chip and may contain connections/couplings for wires, not shown, or radio frequency circuits and an antenna for radio frequency transfer of power and signals from the strain gage 366 to an interrogator mounted on the vehicle, not shown. In this manner, the interrogator supplies power and receives the instantaneous strain value that is measured by the strain gage 366. Although a single strain element 366 has been illustrated, the bolt 360 may contain 1, 2, or even as many as 4 such strain gage assemblies on various sides of bolt section 365. Another example of a stud which is threaded on both ends and which can be used to measure the weight of an occupant seat is illustrated in FIGS. 23A-23D. The operation of this device is disclosed in U.S. patent application Ser. No. 09/849,558 wherein the center section of stud 371 is solid. It has been discovered that sensitivity of the device can be significantly improved if a slotted member is used as described in U.S. Pat. No. 5,539,236. FIG. 23A illustrates a SAW strain gage 372 mounted on a substrate and attached to span a slot 374 in a center section 375 of the stud 371. This technique can be used with any other strain-measuring device. FIG. 23B is a side view of the device of FIG. 23A. FIG. 23C illustrates use of a single hole 376 drilled off-center in the center section 375 of the stud 371. The single hole 376 also serves to magnify the strain as sensed by the strain gage 372. It has the advantage in that strain gage 372 does not need to span an open space. The amount of magnification obtained from this design, however, is significantly less than obtained with the design of FIG. 23A. To improve the sensitivity of the device shown in FIG. 23C, multiple smaller holes 377 can be used as illustrated in FIG. 23D. FIG. 23E in an alternate configuration showing three of four gages 372 for determining the bending moments as well as the axial stress in the support member. In operation, the SAW strain gage 372 receives radio frequency waves from an interrogator 378 and returns electromagnetic waves via a respective antenna 373 which are delayed based on the strain sensed by strain gage 372. Occupant weight sensors can give erroneous results if the seatbelt is pulled tight pushing the occupant into the seat. This is particularly a problem when the seatbelt is not attached to the seat. For such cases, it has been proposed to measure the tension in various parts of the seatbelt. Conventional technology requires that such devices be hard-wired into the vehicle complicating the wire harness. Other components of the vehicle can also be wirelessly coupled to the processor or central control module for the purposes of data transmission and/or power transmission. A discussion of some components follows. Seat Systems In more enhanced applications, it is envisioned that components of the seat will be integrated into the power transmission and communication system. In many luxury cars, the seat subsystem is becoming very complicated. Seat manufacturers state that almost all warranty repairs are associated with the wiring and connectors associated with the seat. The reliability of seat systems can therefore be substantially improved and the incidence of failures or warranty repairs drastically reduced if the wires and connectors can be eliminated from the seat subsystem. Today, there are switches located on the seat or at other locations in the vehicle for controlling the forward and backward motions, up and down motions, and rotation of the seat and seat back. These switches are connected to the appropriate motors by wires. Additionally, many seats now contain an airbag that must communicate with a sensor located, for example, in the vehicle door. Many occupant presence sensors and weight sensing systems are also appearing on vehicle seats. Finally, some seats contain heaters and cooling elements, vibrators, and other comfort and convenience devices that require wires and switches. As an example, let us now look at weight sensing. Under the teachings of this invention, silicon strain gage weight sensors can be placed on the bolts that secure each seat to the slide mechanism as shown in FIG. 22. These strain gage subsystems can contain sufficient electronics and inductive pickup coils so as to receive their operational energy from a pair of wires appropriately placed beneath the seats. The seat weight measurements can then be superimposed on the power frequency or transmitted wirelessly using RF or other convenient wireless technology. Other weight sensing technologies such as bladders and pressure sensors or two-dimensional resistive deflection sensing mats can also be handled in a similar manner. Other methods of seat weight sensing include measuring the deflection of a part of the seat or the deflection of the bolts that connect the seat to the seat slide. For example, the strain in a bolt can be readily determined using SAW, wire or silicon strain gages, optical fiber strain gages, time of flight of ultrasonic waves traveling through the strained bolt, or the capacitive change of two appropriately position capacitor plates. Using the loosely coupled inductive system, power in excess of a kilowatt can be readily transferred to operate seat position motors without the use of directly connected wires. The switches can also be coupled into the inductive system without any direct wire connections and the switches, which now can be placed on the door armrest or on the seat as desired, can provide the information to control the seat motors. Additionally, since microprocessors will now be present on every motor and switch, the classical problem of the four-way seat system to control three degrees of freedom can be easily solved. In current four-way seat systems, when an attempt is made to vertically raise the seat, the seat also rotates. Similarly, when an attempt is made to rotate the seat, it also invariably moves either up or down. This is because there are four switches to control three degrees of freedom and thus there is an infinite combination of switch settings for each seat position setting. This problem can be easily solved with an algorithm that translates the switch settings to the proper motor positions. The positions of the seat, seatback and headrest, can also be readily monitored without having direct wire connections to the vehicle. This can be done in numerous ways beginning with the encoder system that is currently in use and ending with simple RFID radar reflective tags that can be interrogated by a remote RFID tag reader. Based on the time of flight of radar waves, the positions of all of the desired surfaces of the seat can be instantly determined wirelessly. 1.6 Vehicle or Component Control The invention is also particularly useful in light of the foreseeable implementation of smart highways. Smart highways will result in vehicles traveling down highways under partial or complete control of an automatic system, i.e., not being controlled by the driver. The on-board diagnostic system will thus be able to determine failure of a component prior to or upon failure thereof and inform the vehicle's guidance system to cause the vehicle to move out of the stream of traffic, i.e., onto a shoulder of the highway, in a safe and orderly manner. Moreover, the diagnostic system may be controlled or programmed to prevent the movement of the disabled vehicle back into the stream of traffic until the repair of the component is satisfactorily completed. In a method in accordance with this embodiment, the operation of the component would be monitored and if abnormal operation of the component is detected, e.g., by any of the methods and apparatus disclosed herein (although other component failure systems may of course be used in this implementation), the guidance system of the vehicle which controls the movement of the vehicle would be notified, e.g., via a signal from the diagnostic module to the guidance system, and the guidance system would be programmed to move the vehicle out of the stream of traffic, or off of the restricted roadway, possibly to a service station or dealer, upon reception of the particular signal from the diagnostic module. The automatic guidance systems for vehicles traveling on highways may be any existing system or system being developed, such as one based on satellite positioning techniques or ground-based positioning techniques. Since the guidance system may be programmed to ascertain the vehicle's position on the highway, it can determine the vehicle's current position, the nearest location out of the stream of traffic, or off of the restricted roadway, such as an appropriate shoulder or exit to which the vehicle may be moved, and the path of movement of the vehicle from the current position to the location out of the stream of traffic, or off of the restricted roadway. The vehicle may thus be moved along this path under the control of the automatic guidance system. In the alternative, the path may be displayed to a driver and the driver can follow the path, i.e., manually control the vehicle. The diagnostic module and/or guidance system may be designed to prevent re-entry of the vehicle into the stream of traffic, or off of the restricted roadway, until the abnormal operation of the component is satisfactorily addressed. FIG. 24 is a flow chart of some of the methods for directing a vehicle off of a roadway if a component is operating abnormally. The component's operation is monitored at step 380 and a determination is made at step 381 whether its operation is abnormal. If not, the operation of the component is monitored further. If the operation of the component is abnormal, the vehicle can be directed off the roadway at step 382. More particularly, this can be accomplished by generating a signal indicating the abnormal operation of the component at step 383, directing this signal to a guidance system in the vehicle at step 384 that guides movement of the vehicle off of the roadway at step 385. Also, if the component is operating abnormally, the current position of the vehicle and the location of a site off of the roadway can be determined at step 386, e.g., using satellite-based or ground-based location determining techniques, a path from the current location to the off-roadway location determined at step 387 and then the vehicle directed along this path at step 388. Periodically, a determination is made at step 389 whether the component's abnormality has been satisfactorily addressed and/or corrected and if so, the vehicle can re-enter the roadway and operation of the component begins again. If not, the re-entry of the vehicle onto the roadway is prevented at step 390. FIG. 25 schematically shows the basic components for performing this method, i.e., a component operation monitoring system 391 (such as described above), an optional satellite-based or ground-based positioning system 392 and a vehicle guidance system 393. 2.0 Telematics Described above is a system for determining the status of occupants in a vehicle, and in the event of an accident or at any other appropriate time, transmitting the status of the occupants, and optionally additional information, via a communications channel or link to a remote monitoring facility. In addition to the status of the occupant, it is also important to be able to analyze the operating conditions of the vehicle and detect when a component of the vehicle is about to fail. By notifying the driver of the impending failure of the component, appropriate corrective action can be taken to avoid such failure. As noted above, at least one invention herein relates generally to telematics and the transmission of information from a vehicle to one or more remote sites which can react to the position or status of the vehicle or occupant(s) therein. Initially, sensing of the occupancy of the vehicle and the optional transmission of this information, which may include images, to remote locations will be discussed. This entails obtaining information from various sensors about the occupant(s) in the passenger compartment of the vehicle, e.g., the number of occupants, their type and their motion, if any. Thereafter, a discussion of general vehicle diagnostic methods will be discussed with the diagnosis being transmittable via a communications device to the remote locations. Finally, an extensive discussion of various sensors for use on the vehicle to sense different operating parameters and conditions of the vehicle is provided. All of the sensors discussed herein can be coupled to a communications device enabling transmission of data, signals and/or images to the remote locations, and reception of the same from the remote locations. FIG. 26 shows schematically the interface between a vehicle interior monitoring system in accordance with the invention and the vehicle's cellular or other telematics communication system. An adult occupant 395 is shown sitting on the front passenger seat 343 and four transducers 344, 345, 347 and 348 are used to determine the presence (or absence) of the occupant on that seat 343. One of the transducers 345 in this case acts as both a transmitter and receiver while transducer 344 can act only as a receiver or as both a transmitter and receiver. Alternately, transducer 344 could serve as both a transmitter and receiver or the transmitting function could be alternated between the two transducers 344, 345. Also, in many cases more than two transmitters and receivers are used and in still other cases, other types of sensors, such as electric field, capacitance, self-tuning antennas (collectively represented by 347 and 348), weight, seatbelt, heartbeat, motion and seat position sensors, are also used in combination with the radiation sensors. For a general object, transducers 344, 345, 347, 348 can also be used to determine the type of object, determine the location of the object and/or determine another property or characteristic of the object. A property of the object could be the orientation of a child seat, the velocity of an adult and the like. For example, the transducers 344, 345, 347, 348 can be designed to enable a determination that an object is present on the seat, that the object is a child seat and that the child seat is rear-facing. The transducers 344 and 345 are attached to the vehicle buried in the A-pillar trim, where their presence can be disguised, and are connected to processor 340 that may also be hidden in the trim as shown (this being a non-limiting position for the processor 340). Other mounting locations can also be used. For example, transducers 344, 345 can be mounted inside the seat (along with or in place of transducers 347 and 348), in the ceiling of the vehicle, in the B-pillar, in the C-pillar and in the doors. Indeed, the vehicle interior monitoring system in accordance with the invention may comprise a plurality of monitoring units, each arranged to monitor a particular seating location. In this case, for the rear seating locations, transducers might be mounted in the B-pillar or C-pillar or in the rear of the front seat or in the rear side doors. Possible mounting locations for transducers, transmitters, receivers and other occupant sensing devices are disclosed in the above-referenced patents and patent applications and all of these mounting locations are contemplated for use with the transducers described herein. The cellular phone or other communications system 396 outputs to an antenna 397. The transducers 344, 345, 347 and 348 in conjunction with the pattern recognition hardware and software, which is implemented in processor 340 and is packaged on a printed circuit board or flex circuit along with the transducers 344 and 345, determine the presence of an occupant within a few seconds after the vehicle is started, or within a few seconds after the door is closed. Similar systems located to monitor the remaining seats in the vehicle also determine the presence of occupants at the other seating locations and this result is stored in the computer memory which is part of each monitoring system processor 340. Periodically and in particular in the event of or in anticipation of an accident, the electronic system associated with the cellular phone system 396 interrogates the various interior monitoring system memories and arrives at a count of the number of occupants in the vehicle, and optionally, even makes a determination as to whether each occupant was wearing a seatbelt and if he or she is moving after the accident. The phone or other communications system then automatically dials the EMS operator (such as 911 or through a telematics service such as OnStar®) and the information obtained from the interior monitoring systems is forwarded so that a determination can be made as to the number of ambulances and other equipment to send to the accident site, for example. Such vehicles will also have a system, such as the global positioning system, which permits the vehicle to determine its exact location and to forward this information to the EMS operator. An alternate preferred communications system is the use of satellite internet or Wi-Fi internet such is expected to be operational in a few years. In this manner, the vehicle will always have communications access regardless of its location on the earth. This is based on the premise that Wi-Fi will be in place for all those locations where satellite communication is not available such as in tunnels, urban canyons and the like. Thus, in basic embodiments of the invention, wave or other energy-receiving transducers are arranged in the vehicle at appropriate locations, trained if necessary depending on the particular embodiment, and function to determine whether a life form is present in the vehicle and if so, how many life forms are present and where they are located etc. To this end, transducers can be arranged to be operative at only a single seating locations or at multiple seating locations with a provision being made to eliminate repetitive count of occupants. A determination can also be made using the transducers as to whether the life forms are humans, or more specifically, adults, children in child seats, etc. As noted above, this is possible using pattern recognition techniques. Moreover, the processor or processors associated with the transducers can be trained to determine the location of the life forms, either periodically or continuously or possibly only immediately before, during and after a crash. The location of the life forms can be as general or as specific as necessary depending on the system requirements, i.e., that a human is situated on the driver's seat in a normal position (general) or a determination can be made that a human is situated on the driver's seat and is leaning forward and/or to the side at a specific angle as well as the position of his or her extremities and head and chest (specifically). The degree of detail is limited by several factors, including, for example, the number and position of transducers and training of the pattern recognition algorithm. In addition to the use of transducers to determine the presence and location of occupants in a vehicle, other sensors could also be used. For example, a heartbeat sensor which determines the number and presence of heartbeats can also be arranged in the vehicle, which would thus also determine the number of occupants as the number of occupants would be equal to the number of heartbeats. Conventional heartbeat sensors can be adapted to differentiate between a heartbeat of an adult, a heartbeat of a child and a heartbeat of an animal. As its name implies, a heartbeat sensor detects a heartbeat, and the magnitude thereof, of a human occupant of the seat, if such a human occupant is present. The output of the heartbeat sensor is input to the processor of the interior monitoring system. One heartbeat sensor for use in the invention may be of the types as disclosed in McEwan (U.S. Pat. No. 5,573,012 and U.S. Pat. No. 5,766,208). The heartbeat sensor can be positioned at any convenient position relative to the seats where occupancy is being monitored. A preferred location is within the vehicle seat back. An alternative way to determine the number of occupants is to monitor the weight being applied to the seats, i.e., each seating location, by arranging weight sensors at each seating location which might also be able to provide a weight distribution of an object on the seat. Analysis of the weight and/or weight distribution by a predetermined method can provide an indication of occupancy by a human, an adult or child, or an inanimate object. Another type of sensor which is not believed to have been used in an interior monitoring system heretofore is a micropower impulse radar (MIR) sensor which determines motion of an occupant and thus can determine his or her heartbeat (as evidenced by motion of the chest). Such an MIR sensor can be arranged to detect motion in a particular area in which the occupant's chest would most likely be situated or could be coupled to an arrangement which determines the location of the occupant's chest and then adjusts the operational field of the MIR sensor based on the determined location of the occupant's chest. A motion sensor utilizing a micro-power impulse radar (MIR) system is disclosed, for example, in McEwan (U.S. Pat. No. 5,361,070), as well as many other patents by the same inventor. Motion sensing is accomplished by monitoring a particular range from the sensor, as disclosed in that patent. MIR is one form of radar which has applicability to occupant sensing and can be mounted at various locations in the vehicle. It has an advantage over ultrasonic sensors in that data can be acquired at a higher speed and thus the motion of an occupant can be more easily tracked. The ability to obtain returns over the entire occupancy range is somewhat more difficult than with ultrasound resulting in a more expensive system overall. MIR has additional advantages in lack of sensitivity to temperature variation and has a comparable resolution to about 40 kHz ultrasound. Resolution comparable to higher frequency is also possible. Additionally, multiple MIR sensors can be used when high speed tracking of the motion of an occupant during a crash is required since they can be individually pulsed without interfering with each through time division multiplexing. An alternative way to determine motion of the occupant(s) is to monitor the weight distribution of the occupant whereby changes in weight distribution after an accident would be highly suggestive of movement of the occupant. A system for determining the weight distribution of the occupants could be integrated or otherwise arranged in the right center and left, front and back vehicle seats such as 343 and several patents and publications describe such systems. More generally, any sensor which determines the presence and health state of an occupant can also be integrated into the vehicle interior monitoring system in accordance with the invention. For example, a sensitive motion sensor can determine whether an occupant is breathing and a chemical sensor can determine the amount of carbon dioxide, or the concentration of carbon dioxide, in the air in the vehicle which can be correlated to the health state of the occupant(s). The motion sensor and chemical sensor can be designed to have a fixed operational field situated where the occupant's mouth is most likely to be located. In this manner, detection of carbon dioxide in the fixed operational field could be used as an indication of the presence of a human occupant in order to enable the determination of the number of occupants in the vehicle. In the alternative, the motion sensor and chemical sensor can be adjustable and adapted to adjust their operational field in conjunction with a determination by an occupant position and location sensor which would determine the location of specific parts of the occupant's body, e.g., his or her chest or mouth. Furthermore, an occupant position and location sensor can be used to determine the location of the occupant's eyes and determine whether the occupant is conscious, i.e., whether his or her eyes are open or closed or moving. The use of chemical sensors can also be used to detect whether there is blood present in the vehicle, for example, after an accident. Additionally, microphones can detect whether there is noise in the vehicle caused by groaning, yelling, etc., and transmit any such noise through the cellular or other communication connection to a remote listening facility (such as operated by OnStar®). FIG. 27 shows a schematic diagram of an embodiment of the invention including a system for determining the presence and health state of any occupants of the vehicle and a telecommunications link. This embodiment includes a system for determining the presence of any occupants 400 which may take the form of a heartbeat sensor or motion sensor as described above and a system for determining the health state of any occupants 401. The health state determining system may be integrated into the system for determining the presence of any occupants, i.e., one and the same component, or separate therefrom. Further, a system for determining the location, and optionally velocity, of the occupants or one or more parts thereof 402 are provided and may be any conventional occupant position sensor or preferably, one of the occupant position sensors as described herein (e.g., those utilizing waves electromagnetic radiation or electric fields) or as described in the current assignee's patents and patent applications referenced above. A processor 403 is coupled to the presence determining system 400, the health state determining system 401 and the location determining system 402. A communications unit 404 is coupled to the processor 403. The processor 403 and/or communications unit 404 can also be coupled to microphones 405 that can be distributed throughout the vehicle and include voice-processing circuitry to enable the occupant(s) to effect vocal control of the processor 403, communications unit 404 or any coupled component or oral communications via the communications unit 404. The processor 403 is also coupled to another vehicular system, component or subsystem 406 and can issue control commands to effect adjustment of the operating conditions of the system, component or subsystem. Such a system, component or subsystem can be the heating or air-conditioning system, the entertainment system, an occupant restraint device such as an airbag, a glare prevention system, etc. Also, a positioning system 407 could be coupled to the processor 403 and provides an indication of the absolute position of the vehicle, preferably using satellite-based positioning technology (e.g., a GPS receiver). In normal use (other than after a crash), the presence determining system 400 determines whether any human occupants are present, i.e., adults or children, and the location determining system 402 determines the occupant's location. The processor 403 receives signals representative of the presence of occupants and their location and determines whether the vehicular system, component or subsystem 406 can be modified to optimize its operation for the specific arrangement of occupants. For example, if the processor 403 determines that only the front seats in the vehicle are occupied, it could control the heating system to provide heat only through vents situated to provide heat for the front-seated occupants. Another possible vehicular system, component or subsystem is a navigational aid, i.e., a route display or map. In this case, the position of the vehicle as determined by the positioning system 407 is conveyed through processor 403 to the communications unit 404 to a remote facility and a map is transmitted from this facility to the vehicle to be displayed on the route display. If directions are needed, a request for the same could be entered into an input unit 408 associated with the processor 403 and transmitted to the facility. Data for the display map and/or vocal instructions could be transmitted from this facility to the vehicle. Moreover, using this embodiment, it is possible to remotely monitor the health state of the occupants in the vehicle and most importantly, the driver. The health state determining system 401 may be used to detect whether the driver's breathing is erratic or indicative of a state in which the driver is dozing off. The health state determining system 401 could also include a breath-analyzer to determine whether the driver's breath contains alcohol. In this case, the health state of the driver is relayed through the processor 403 and the communications unit 404 to the remote facility and appropriate action can be taken. For example, it would be possible to transmit a command (from the remote facility) to the vehicle to activate an alarm or illuminate a warning light or if the vehicle is equipped with an automatic guidance system and ignition shut-off, to cause the vehicle to come to a stop on the shoulder of the roadway or elsewhere out of the traffic stream. The alarm, warning light automatic guidance system and ignition shut-off are thus particular vehicular components or subsystems represented by 406. In use after a crash, the presence determining system 400, health state determining system 401 and location determining system 402 can obtain readings from the passenger compartment and direct such readings to the processor 403. The processor 403 analyzes the information and directs or controls the transmission of the information about the occupant(s) to a remote, manned facility. Such information would include the number and type of occupants, i.e., adults, children, infants, whether any of the occupants have stopped breathing or are breathing erratically, whether the occupants are conscious (as evidenced by, e.g., eye motion), whether blood is present (as detected by a chemical sensor) and whether the occupants are making noise. Moreover, the communications link through the communications unit 404 can be activated immediately after the crash to enable personnel at the remote facility to initiate communications with the vehicle. An occupant sensing system can also involve sensing for the presence of a living occupant in a trunk of a vehicle or in a closed vehicle, for example, when a child is inadvertently left in the vehicle or enters the trunk and the trunk closes. To this end, a SAW-based chemical sensor 410 is illustrated in FIG. 28A for mounting in a vehicle trunk as illustrated in FIG. 28. The chemical sensor 410 is designed to measure carbon dioxide concentration through the mass loading effects as described in U.S. Pat. No. 4,895,017, which is incorporated by reference herein, with a polymer coating selected that is sensitive to carbon dioxide. The speed of the surface acoustic wave is a function of the carbon dioxide level in the atmosphere. Section 412 of the chemical sensor 410 contains a coating of such a polymer and the acoustic velocity in this section is a measure of the carbon dioxide concentration. Temperature effects are eliminated through a comparison of the sonic velocities in sections 412 and 411 as described above. Thus, when the trunk lid 409 is closed and a source of carbon dioxide such as a child or animal is trapped within the trunk, the chemical sensor 410 will provide information indicating the presence of the carbon dioxide producing object to the interrogator which can then release a trunk lock permitting the trunk lid 409 to automatically open. In this manner, the problem of children and animals suffocating in closed trunks is eliminated. Alternately, information that a person or animal is trapped in a trunk can be sent by the telematics system to law enforcement authorities or other location or facility remote from the vehicle. A similar device can be distributed at various locations within the passenger compartment of vehicle along with a combined temperature sensor. If the car has been left with a child or other animal while owner is shopping, for example, and if the temperature rises within the vehicle to an unsafe level or, alternately, if the temperature drops below an unsafe level, then the vehicle can be signaled to take appropriate action which may involve opening the windows or starting the vehicle with either air conditioning or heating as appropriate. Alternately, information that a person or animal is trapped within a vehicle can be sent by the telematics system to law enforcement authorities or other location remote from the vehicle. Thus, through these simple wireless powerless sensors, the problem of suffocation either from lack of oxygen or death from excessive heat or cold can all be solved in a simple, low-cost manner through using an interrogator as disclosed in the current assignee's U.S. patent application Ser. No. 10/079,065. Additionally, a sensitive layer on a SAW can be made to be sensitive to other chemicals such as water vapor for humidity control or alcohol for drunk-driving control. Similarly, the sensitive layer can be designed to be sensitive to carbon monoxide thereby preventing carbon monoxide poisoning. Many other chemicals can be sensed for specific applications such as to check for chemical leaks in commercial vehicles, for example. Whenever such a sensor system determines that a dangerous situation is developing, an alarm can be sounded and/or the situation can be automatically communicated to an off-vehicle location through the internet, telematics, a cell phone such as a 911 call, the Internet or though a subscriber service such as OnStar®. The operating conditions of the vehicle can also be transmitted along with the status of the occupants to a remote monitoring facility. The operating conditions of the vehicle include whether the motor is running and whether the vehicle is moving. Thus, in a general embodiment in which information on both occupancy of the vehicle and the operating conditions of the vehicle are transmitted, one or more properties or characteristics of occupancy of the vehicle are determined, such constituting information about the occupancy of the vehicle, and one or more states of the vehicle or of a component of the vehicle is determined, such constituting information about the operation of the vehicle. The information about the occupancy of the vehicle and operation of the vehicle are selectively transmitted, possibly the information about occupancy to an emergency response center and the information about the vehicle to a dealer or repair facility. Transmission of the information about the operation of the vehicle, i.e., diagnostic information, may be achieved via a satellite and/or via the Internet. The vehicle would thus include appropriate electronic hardware and/or software to enable the transmission of a signal to a satellite, from where it could be retransmitted to a remote location, and/or to enable the transmission to a web site or host computer. In the latter case, the vehicle could be assigned a domain name or e-mail address for identification or transmission origination purposes. The diagnostic discussion above has centered on notifying the vehicle operator of a pending problem with a vehicle component. Today, there is great competition in the automobile marketplace and the manufacturers and dealers who are most responsive to customers are likely to benefit by increased sales both from repeat purchasers and new customers. The diagnostic module disclosed herein benefits the dealer by making him instantly aware, through the cellular telephone system, or other communication link, coupled to the diagnostic module or system in accordance with the invention, when a component is likely to fail. As envisioned when the diagnostic module 33 detects a potential failure it not only notifies the driver through a display 34 (as shown in FIGS. 3 and 4), but also automatically notifies the dealer through a vehicle cellular phone 32 or other telematics communication link such as the internet via satellite or Wi-Fi. The dealer can thus contact the vehicle owner and schedule an appointment to undertake the necessary repair at each party's mutual convenience. Contact by the dealer to the vehicle owner can occur as the owner is driving the vehicle, using a communications device. Thus, the dealer can contact the driver and informed him of their mutual knowledge of the problem and discuss scheduling maintenance to attend to the problem. The customer is pleased since a potential vehicle breakdown has been avoided and the dealer is pleased since he is likely to perform the repair work. The vehicle manufacturer also benefits by early and accurate statistics on the failure rate of vehicle components. This early warning system can reduce the cost of a potential recall for components having design defects. It could even have saved lives if such a system had been in place during the Firestone tire failure problem mentioned above. The vehicle manufacturer will thus be guided toward producing higher quality vehicles thus improving his competitiveness. Finally, experience with this system will actually lead to a reduction in the number of sensors on the vehicle since only those sensors that are successful in predicting failures will be necessary. For most cases, it is sufficient to notify a driver that a component is about to fail through a warning display. In some critical cases, action beyond warning the driver may be required. If, for example, the diagnostic module detected that the alternator was beginning to fail, in addition to warning the driver of this eventuality, the diagnostic system could send a signal to another vehicle system to turn off all non-essential devices which use electricity thereby conserving electrical energy and maximizing the time and distance that the vehicle can travel before exhausting the energy in the battery. Additionally, this system can be coupled to a system such as OnStar®) or a vehicle route guidance system, and the driver can be guided to the nearest open repair facility or a facility of his or her choice. FIG. 29 shows a schematic of the integration of the occupant sensing with a telematics link and the vehicle diagnosis with a telematics link. As envisioned, the occupant sensing system 415 includes those components which determine the presence, position, health state, and other information relating to the occupants, for example the transducers discussed above with reference to FIGS. 20 and 27 and the SAW device discussed above with reference to FIG. 28. Information relating to the occupants includes information as to what the driver is doing, talking on the phone, communicating with OnStar®, the internet or other route guidance, listening to the radio, sleeping, drunk, drugged, having a heart attack, etc. The occupant sensing system may also be any of those systems and apparatus described in any of the current assignee's above-referenced patents and patent applications or any other comparable occupant sensing system which performs any or all of the same functions as they relate to occupant sensing. Examples of sensors which might be installed on a vehicle and constitute the occupant sensing system include heartbeat sensors, motion sensors, weight sensors, microphones and optical sensors. A crash sensor 416 is provided and determines when the vehicle experiences a crash. Crash sensor 416 may be any type of crash sensor. Vehicle sensors 417 include sensors which detect the operating conditions of the vehicle such as those sensors discussed with reference to FIG. 28 and others above. Also included are tire sensors such as disclosed in U.S. patent application Ser. No. 10/079,065. Other examples include velocity and acceleration sensors, and angular and angular rate pitch, roll and yaw sensors. Of particular importance are sensors that tell what the car is doing: speed, skidding, sliding, location, communicating with other cars or the infrastructure, etc. Environment sensors 418 include sensors which provide data to the operating environment of the vehicle, e.g., the inside and outside temperatures, the time of day, the location of the sun and lights, the locations of other vehicles, rain, snow, sleet, visibility (fog), general road condition information, pot holes, ice, snow cover, road visibility, assessment of traffic, video pictures of an accident, etc. Possible sensors include optical sensors which obtain images of the environment surrounding the vehicle, blind spot detectors which provide data on the blind spot of the driver, automatic cruise control sensors that can provide images of vehicles in front of the host vehicle, and various radar devices which provide the position of other vehicles and objects relative to the subject vehicle. The occupant sensing system 415, crash sensors 416, vehicle sensors 417, and environment sensors 418 can all be coupled to a communications device 419 which may contain a memory unit and appropriate electrical hardware to communicate with all of the sensors, process data from the sensors, and transmit data from the sensors. The memory unit would be useful to store data from the sensors, updated periodically, so that such information could be transmitted at set time intervals. The communications device 419 can be designed to transmit information to any number of different types of facilities. For example, the communications device 419 could be designed to transmit information to an emergency response facility 420 in the event of an accident involving the vehicle. The transmission of the information could be triggered by a signal from the crash sensor 416 that the vehicle was experiencing a crash or had experienced a crash. The information transmitted could come from the occupant sensing system 415 so that the emergency response could be tailored to the status of the occupants. For example, if the vehicle was determined to have ten occupants, more ambulances might be sent than if the vehicle contained only a single occupant. Also, if the occupants are determined not be breathing, then a higher priority call with living survivors might receive assistance first. As such, the information from the occupant sensing system 415 could be used to prioritize the duties of the emergency response personnel. Information from the vehicle sensors 417 and environment sensors 418 could also be transmitted to law enforcement authorities 422 in the event of an accident so that the cause(s) of the accident could be determined. Such information can also include information from the occupant sensing system 415, which might reveal that the driver was talking on the phone, putting on make-up, or another distracting activity, information from the vehicle sensors 417 which might reveal a problem with the vehicle, and information from the environment sensors 418 which might reveal the existence of slippery roads, dense fog and the like. Information from the occupant sensing system 415, vehicle sensors 417 and environment sensors 418 could also be transmitted to the vehicle manufacturer 423 in the event of an accident so that a determination can be made as to whether failure of a component of the vehicle causes or contributed to the cause of the accident. For example, the vehicle sensors might determine that the tire pressure was too low so that advice can be disseminated to avoid maintaining the tire pressure too low in order to avoid an accident. Information from the vehicle sensors 417 relating to component failure could be transmitted to a dealer/repair facility 421 which could schedule maintenance to correct the problem. The communications device 419 could be designed to transmit particular information to each site, i.e., only information important to be considered by the personnel at that site. For example, the emergency response personnel have no need for the fact that the tire pressure was too low but such information is important to the law enforcement authorities 422 (for the possible purpose of issuing a recall of the tire and/or vehicle) and the vehicle manufacturer 423. The communication device can be a cellular phone, OnStar® or other subscriber-based telematics system, a peer-to-peer vehicle communication system that eventually communicates to the infrastructure and then, perhaps, to the Internet with e-mail to the dealer, manufacturer, vehicle owner, law enforcement authorities or others. It can also be a vehicle to LEO or Geostationary satellite system such as SkyBitz which can then forward the information to the appropriate facility either directly or through the Internet or a direct connection to the internet through a satellite or Wi-Fi link. The communication may need to be secret so as not to violate the privacy of the occupants and thus encrypted communication may, in many cases, be required. Other innovations described herein include the transmission of any video data from a vehicle to another vehicle or to a facility remote from the vehicle by any means such as a telematics communication system such as OnStar, a cellular phone system, a communication via GEO, geocentric or other satellite system and any communication that communicates the results of a pattern recognition system analysis. Also, any communication from a vehicle can combine sensor information with location information. When optical sensors are provided as part of the occupant sensing system 415, video conferencing becomes a possibility, whether or not the vehicle experiences a crash. That is, the occupants of the vehicle can engage in a video conference with people at another location 424 via establishment of a communications channel by the communications device 419. The vehicle diagnostic system described above using a telematics link can transmit information from any type of sensors on the vehicle. In one particular use of the invention, a wireless sensing and communication system is provided whereby the information or data obtained through processing of input from sensors of the wireless sensing and communication system is further transmitted for reception by a remote facility. Thus, in such a construction, there is an intra-vehicle communications between the sensors on the vehicle and a processing system (control module, computer or the like) and remote communications between the same or a coupled processing system (control module, computer or the like). The electronic components for the intra-vehicle communication may be designed to transmit and receive signals over short distances whereas the electronic components which enable remote communications should be designed to transmit and receive signals over relatively long distances. The wireless sensing and communication system includes sensors that are located on the vehicle or in the vicinity of the vehicle and which provide information which is transmitted to one or more interrogators in the vehicle by wireless radio frequency means, using wireless radio frequency transmission technology. In some cases, the power to operate a particular sensor is supplied by the interrogator while in other cases, the sensor is independently connected to either a battery, generator, vehicle power source or some source of power external to the vehicle. One particular system requires mentioning which is the use of high speed satellite or Wi-Fi internet service such as supplied by Wi-Fi hot spots or KVH Industries, Inc. for vehicle telephone, TV and radio services. With thousands of radio stations available over the internet, for example, a high speed internet connection is clearly superior to satellite radio systems that are now being marketed. Similarly, with ubiquitous internet access that KVH supplies throughout the country, the lack of coverage problems with cell phones disappears. This capability becomes particularly useful for emergency notification when a vehicle has an accident or becomes disabled. There is a serious problem developing with vehicles such as cars, trucks, boats and private planes and computer systems. The quality and lifetime of vehicles is increasing and now many vehicles have a lifetime that exceeds ten or more years. On the other hand, computer and related electronic systems have shorter and shorter lift spans as they are made obsolete by the exponential advances in technology. Owners do not want to dispose of their vehicles just because the electronics have become obsolete. Therefore, a solution as proposed in this invention, whereby the information, programs, processing power and memory is made separate from the vehicle, will increasingly become necessary. One implementation of such as system is for the information, programs, processing power and memory to be resident in a portable device that can be removed from the vehicle. Once removed, the vehicle may still be operable but with reduced functionality. The navigation system, for example, may be resident in the removable device which hereinafter will be referred to as a Personal Information Device (PID) including a GPS subsystem and perhaps an IMU along with appropriate maps allowing a person to navigate on foot as well as in the vehicle. The telephone system which can be either internet or cell phone-based and if internet-based, can be either satellite internet, Wi-Fi or equivalent system which would be equally operable in a vehicle or on foot. The software data and programs can be kept updated including all of the software for diagnostic functions, for example, for the vehicle through the internet connection. The vehicle would contain supplemental displays, input devices including voice recognition and cameras for occupant position determination, and other output devices such as speakers, warning lights etc., for example. As computer hardware improves it can be an easy step for the owner to replace the PID with the latest version which may even be supplied to the owner under subscription by the Cell Phone Company, car dealership, vehicle manufacturer, computer manufacturer etc. Similarly, the same device can be used to operate the home computer system or entertainment system. In other words, the owner would own one device, the PID, that would contain substantially all of the processing power, software and information that the owner requires to operate his vehicles, computer systems etc. The system can also be periodically backed up, automatically providing protection against loss of data in the event of a system failure. The PID can also have a biometrics-based identification system that prevents unauthorized users from using the system and an automatic call back location system based on GPS or other location technologies that permits the owner to immediately find the location of the PID in the event of misplacement or theft. The PID can also be the repository of credit card information permitting instant purchases without the physical scanning of a separate credit card and other information of a medical nature to air emergency services in the event of a medical emergency. The possibilities are limitless for such a device. A PID, for example, can be provided with sensors to monitor the vital functions of an elderly person and signal if a problem occurs. The PID can be programmed and provided with sensors to sense fire, cold, harmful chemicals or vapors for use in a vehicle or any other environment. Since the PID would have universal features, it could be taken from vehicle to vehicle allowing each person to have personal features in whatever vehicle he or she was operating. This would be useful for rental vehicles, for example. The same PID can also be used to signal the presence of a particular person in a room and thereby to set the appropriate TV or radio stations, room temperature, lighting, wall pictures etc. For example, the PID could also assume the features of a remote when a person is watching TV. A person could of course have more than one PID and a PID could be used by more than one person provided a means of identification is present such as a biometric based ID or password system. Thus, each individual would need to learn to operate one device, the PID, instead of multiple devices. The PID could even be used to automatically unlock and initiate some action such as opening a door or turning on lights in a vehicle, house, apartment or building. Naturally, the PID can have a variety of associated sensors as discussed above including cameras, microphones, accelerometers, an IMU, GPS receiver, Wi-Fi receiver etc. Other people could also determine the location of a person carrying the PID, if such a service is authorized by the PID owner. In this manner, parents can locate their children or friends can locate each other in a crowded restaurant or airport. The location or tracking information can be made available on the internet through the Skybitz or similar low power tracking system. Also, the batteries that operate the PID can be recharged in a variety of ways including fuel cells and vibration-based power generators. 3.0 Wiring and Busses In the discussion above, the diagnostic module of this invention assumes that a vehicle data bus exists which is used by all of the relevant sensors on the vehicle. Most vehicles today do not have a data bus although it is widely believed that most vehicles will have one in the future. The relevant signals can be transmitted to the diagnostic module through a variety of coupling systems other than through a data bus and this invention is not limited to vehicles having a data bus. For example, the data can be sent wirelessly to the diagnostic module using the Bluetooth™ specification. In some cases, even the sensors do not have to be wired and can obtain their power via RF from the interrogator as is well known in the RFID-radio frequency identification (either silicon or surface acoustic wave (SAW)-based)) field. Alternately, an inductive or capacitive power transfer system can be used. Several technologies have been described above all of which have the objective of improving the reliability and reducing the complexity of the wiring system in an automobile and particularly the safety system. Most importantly, the bus technology described has as its objective simplification and increase in reliability of the vehicle wiring system. This wiring system was first conceived of as a method for permitting the location of airbag crash sensors at locations where they can most effectively sense a vehicle crash and yet permit that information to be transmitted to airbag control circuitry which may be located in a protective portion of the interior of the vehicle or may even be located on the airbag module itself Protecting this affirmation transmission requires a wiring system that is far more reliable and resistant to being destroyed in the very crash that the sensor is sensing. This led to the realization that the data bus that carries the information from the crash sensor must be particularly reliable. Upon designing such a data bus, however, it was found that the capacity of that data bus far exceeded the needs of the crash sensor system. This then led to a realization that the capacity, or bandwidth, of such a bus would be sufficient to carry all of the vehicle information requirements. In some cases, this requires the use of high bandwidth bus technology such as twisted pair wires, shielded twisted pair wires, or coax cable. If a subset of all of the vehicle devices is included on the bus, then the bandwidth requirements are less and simpler bus technologies can be used in place of the coax cable, for example. The economics that accompany a data bus design which lies the highest reliability, highest bandwidth, is justified if all of the vehicle devices use the same system. This is where the greatest economies and greatest reliability occur. As described above, this permits, for example, the placement of the airbag firing electronics into the same housing that contains the airbag inflator. Once the integrity of the data bus is assured, such that it will not be destroyed during the crash itself, then the proper place for the airbag intelligence is in the airbag module itself. This further proves the reliability of the system since the shorting of the wires to the airbag module will not inadvertently set off the airbag as has happened frequently in the past. When operating on the vehicle data bus, each device should have a unique address and each associated device must know that address. For most situations, therefore, this address must be predetermined and then assigned through an agreed-upon standard for all vehicles. Thus, the left rear tail light must have a unique address so that when the turn signal is turned to flash that light, it does not also flash the right tail light, for example. Similarly, the side impact crash sensor which will operate on the same data bus as the frontal impact crash sensor, must issue a command to the side impact airbag and not to the frontal impact airbag. One of the key advantages of a single bus system connecting all sensors in the vehicle together is the possibility of using this data bus to diagnose the health of the entire vehicle, as described in the detail above. Thus, there are clear synergistic advantages to all the disparate technologies described above. The design, construction, installation, and maintenance a vehicle data bus network requires attention to a many issues, including: an appropriate communication protocol, physical layer transceivers for the selected media, capable microprocessors for both application and protocol execution, device controller hardware and software for the required sensors and actuators, etc. Such activities are known to those skilled in the art and will not be described in detail here. An intelligent distributed system as described above can be based on the CAN Protocol, for example, which is a common protocol used in the automotive industry. CAN is a full function network protocol that provides both message checking and correction to insure communication integrity. Many of the devices on the system will have special diagnostics designed into them. For instance, some of the inflator controls can send warning messages if their backup power supply has insufficient charge. In order to assure the integrity and reliability of the bus system, most devices will be equipped with bidirectional communication as described above. Thus, when a message is sent to the rear right taillight to turn on, the light can return a message that it has executed the instruction. In a refinement of this embodiment, more of the electronics associated with the airbag system are decentralized and housed within or closely adjacent to each of the airbag modules. Each module has its own electronic package containing a power supply and diagnostic and sometimes also the occupant sensor electronics. One sensor system is still used to initiate deployment of all airbags associated with the frontal impact. To avoid the noise effects of all airbags deploying at the same time, each module sometimes has its own delay. The modules for the rear seat, for example, can have a several millisecond firing delay compared to the module for the driver, and the front passenger module can have a lesser delay. Each of the modules sometimes also has its own occupant position sensor and associated electronics. In this configuration, there is a minimum reliance on the transmission of power and data to and from the vehicle electrical system which is the least reliable part of the airbag system, especially during a crash. Once each of the modules receives a signal from the crash sensor system, it is on its own and no longer needs either power or information from the other parts of the system. The main diagnostics for a module can also reside within the module which transmits either a ready or a fault signal to the main monitoring circuit which now needs only to turn on a warning light if any of the modules either fails to transmit a ready signal or sends a fault signal. The placement of electronic components in or near the airbag module can be important. The placement of the occupant sensing as well as the diagnostics electronics within or adjacent to the airbag module has additional advantages to solving several current important airbag problems. There have been numerous inadvertent airbag deployments caused by wires in the system becoming shorted. Then, when the vehicle hits a pothole, which is sufficient to activate the arming sensor or otherwise disturb the sensing system, the airbag deploys. Such an unwanted deployment of course can directly injure an occupant who is out-of-position or cause an accident that results in occupant injuries. If the sensor were to send a coded signal to the airbag module rather than a DC voltage with sufficient power to trigger the airbag, and if the airbag module had stored within its electronic circuit sufficient energy to initiate the inflator, then these unwanted deployments could be prevented. A shorted wire cannot send a coded signal and the short can be detected by the module resident diagnostic circuitry. This would require that the airbag module contain the backup power supply which further improves the reliability of the system since the electrical connection to the sensor, or to the vehicle power, can now partially fail, as might happen during an accident, and the system will still work properly. It is well known that the electrical resistance in the “clockspring” connection system, which connects the steering wheel-mounted airbag module to the sensor and diagnostic system, is marginal in design and prone to failure. The resistance of this electrical connection must be very low or there will not be sufficient power to reliably initiate the inflator squib. To reduce the resistance to the level required, high quality gold-plated connectors are preferably used and the wires must also be of unusually high quality. Due to space constraints, however, these wires have only a marginally adequate resistance thereby reducing the reliability of the driver airbag module and increasing its cost. If, on the other hand, the power to initiate the airbag were already in the module, then only a coded signal needs to be sent to the module rather than sufficient power to initiate the inflator. Thus, the resistance problem disappears and the module reliability is increased. Additionally, the requirements for the clockspring wires become less severe and the design can be relaxed reducing the cost and complexity of the device. It may even be possible to return to the slip ring system that existed prior to the implementation of airbags. Under this system, the power supply can be charged over a few seconds, since the power does not need to be sent to the module at the time of the required airbag deployment because it is already there. Thus, all of the electronics associated with the airbag system except the sensor and its associated electronics, if any, would be within or adjacent to the airbag module. This includes optionally the occupant sensor, the diagnostics and the backup power supply, which now becomes the primary power supply, and the need for a backup disappears. When a fault is detected, a message is sent to a display unit located typically in the instrument panel. The placement of the main electronics within each module follows the development path that computers themselves have followed from a large centralized mainframe base to a network of microcomputers. The computing power required by an occupant position sensor, airbag system diagnostics and backup power supply is greater than that required by a single point sensor. For this reason, it is more logical to put this electronic package within or adjacent to each module. In this manner, the advantages of a centralized single point sensor and diagnostic system fade since most of the intelligence will reside within or adjacent to the individual modules and not the centralized system. A simple and more effective CrushSwitch sensor such as disclosed in U.S. Pat. No. 5,441,301, for example, now becomes more cost effective than the single point sensor and diagnostic system which is now being widely adopted. Finally, this also is consistent with the migration to a bus system where the power and information are transmitted around the vehicle on a single bus system thereby significantly reducing the number of wires and the complexity of the vehicle wiring system. The decision to deploy an airbag is sent to the airbag module sub-system as a signal not as a burst of power. Although it has been assumed that the information would be sent over a wire bus, it is also possible to send the deploy command by a variety of wireless methods. A partial implementation of the system as just described is depicted schematically in FIG. 30 which shows a view of the combination of an occupant position sensor and airbag module designed to prevent the deployment of the airbag for a seat which is unoccupied or if the occupant is too close to the airbag and therefore in danger of deployment-induced injury. The module, shown generally at 430, includes a housing which comprises an airbag 431, an inflator assembly 432 for the airbag 431, an occupant position sensor comprising an ultrasonic transmitter 433 and an ultrasonic receiver 434. Other occupant position sensors can also be used instead of the ultrasonic transmitter/receiver pair to determine the position of the occupant to be protected by the airbag 431, and also the occupant position sensor (433,434) may be located outside of the housing of the module 430. The housing of the module 430 also contains an electronic module or package 435 coupled to each of the inflator assembly 432, the transmitter 433 and the receiver 434 and which performs the functions of sending the ultrasonic signal to the transmitter 433 and processing the data from the occupant position sensor receiver 434. Electronics module 435 may be arranged within the housing of the module 430 as shown or adjacent or proximate the housing of the module 430. Module 430 also contains a power supply (not shown) for supplying power upon command by the electronics module 435 to the inflator assembly 432 to cause inflation of the airbag 431. Thus, electronics module 435 controls the inflation or deployment of the airbag 431 and may sometimes herein be referred to as a controller or control unit. In addition, the electronic module 435 monitors the power supply voltage, to assure that sufficient energy is stored to initiate the inflator assembly 432 when required, and power the other processes, and reports periodically over the vehicle bus 436 to the central diagnostic module, shown schematically at 437, to indicate that the module is ready, i.e., there is sufficient power of inflate or deploy the airbag 431 and operate the occupant position sensor transmitter/receiver pair 433, 434, or sends a fault code if a failure in any component being monitored has been detected. A CrushSwitch sensor is also shown schematically at 438, which is the only discriminating sensor in the system. Sensor 438 is coupled to the vehicle bus 436 and transmits a coded signal over the bus to the electronics module 435 to cause the electronics module 435 to initiate deployment of the airbag 431 via the inflator assembly 432. The vehicle bus 436 connects the electronic package 435, the central sensor and diagnostic module 437 and the CrushSwitch sensor 438. Bus 436 may be the single bus system, i.e., consists of a pair of wires, on which power and information are transmitted around the vehicle as noted immediately above. Instead of CrushSwitch sensor 438, other crash sensors may be used. When several crash sensors and airbag modules are present in the vehicle, they can all be coupled to the same bus or discrete portions of the airbag modules and crash sensors can be coupled to separate buses. Other ways for connecting the crash sensors and airbag modules to an electrical bus can also be implemented in accordance with the invention such as connecting some of the sensors and/or modules in parallel to a bus and others daisy-chained into the bus. This type of bus architecture is described in U.S. Pat. No. 6,212,457. It should be understood that airbag module 430 is a schematic representation only and thus, may represent any of the airbag modules described above in any of the mounting locations. For example, airbag module 430 may be arranged in connection with the seat 525 as module 510 is in FIG. 31. As such, the bus, which is connected to the airbag module 510, would inherently extend at least partially into and within the seat. Another implementation of the invention incorporating the electronic components into and adjacent to the airbag module as illustrated in FIG. 32 which shows the interior front of the passenger compartment generally at 445. Driver airbag module 446 is partially cutaway to show an electronic module 447 incorporated within the airbag module 446. Electronic module 447 may be comparable to electronic module 435 in the embodiment of FIG. 30 in that it can control the deployment of the airbag in airbag module 446. Electronic airbag module 446 is connected to an electronic sensor illustrated generally as 451 by a wire 448. The electronic sensor 451 is, e.g., an electronic single point crash sensor that initiates the deployment of the airbag when it senses a crash. Passenger airbag module 450 is illustrated with its associated electronic module 452 outside of but adjacent or proximate to the airbag module. Electronic module 452 may be comparable to electronic module 439 in the embodiment of FIG. 30 in that it can control the deployment of the airbag in airbag module 450. Electronic module 452 is connected by a wire 449, which could also be part of a bus, to the electronic sensor 451. One or both of the electronic modules 447 and 452 can contain diagnostic circuitry, power storage capability (either a battery or a capacitor), occupant sensing circuitry, as well as communication electronic circuitry for either wired or wireless communication. It should be understood that although only two airbag modules 446,450 are shown, it is envisioned that an automotive safety network may be designed with several and/or different types of occupant protection devices. Such an automotive network can comprise one or more occupant protection devices connected to the bus, each comprising a housing and a component deployable to provide protection for the occupant, at least one sensor system for providing an output signal relevant to deployment of the deployable component(s) (such as the occupant sensing circuitry), a deployment determining system for generating a signal indicating for which of the deployable components deployment is desired (such as a crash sensor) and an electronic controller arranged in, proximate or adjacent each housing and coupled to the sensor system(s) and the deployment determining system. The electrical bus electrically couples the sensor system(s), the deployment determining system and the controllers so that the signals from one or more of the sensor systems and the deployment determining system are sent over the bus to the controllers. Each controller controls deployment of the deployable component of the respective occupant protection device in consideration of the signals from the sensor system(s) and the deployment determining system. The crash sensor(s) may be arranged separate and at a location apart from the housings and generate a coded signal when deployment of any one of the deployable components is desired. Thus, the coded signal varies depending on which of deployment components are to be deployed. If the deployable component is an airbag associated with the housing, the occupant protection device would comprise an inflator assembly arranged in the housing for inflating the airbag. A connector for joining two coaxial cables 457 and 458 is illustrated in FIGS. 33A, 33B, 33C and 33D generally at 455. A cover 456 is hingably attached to a base 459. A connector plate 461 is slidably inserted into base 459 and contains two abrasion and connection sections 463 and 464. A second connecting plate 465 contains two connecting pins 462, one corresponding to each cable to be connected. To connect the two cables 457 and 458 together, they are first inserted into their respective holes 466 and 467 in base 459 until they are engaged by pins 462. Sliding connector plate 461 is then inserted and cover 460 rotated pushing connector plate 461 downward until the catch 468 snaps over mating catch 469. Other latching devices are of course usable in accordance with the invention. During this process, the serrated part 463 of connector plate 461 abrades the insulating cover off of the outside of the respective cable exposing the outer conductor. The particle coated section 464 of connector plate 461 then engages and makes electrical contact with the outer conductor of the coaxial cables 457 and 458. In this manner, the two coaxial cables 457, 458 are electrically connected together in a very simple manner. Consider now various uses of a bus system. 3.1 Airbag Systems The airbag system currently involves a large number of wires that carry information and power to and from the airbag central processing unit. Some vehicles have sensors mounted in the front of the vehicle and many vehicles also have sensors mounted in the side doors. In addition, there are sensors and an electronic control module mounted in the passenger compartment. All cars now have passenger and driver airbags and some vehicles have as many as eight airbags considering the side impact torso airbag and head airbags as well as knee bolster airbags. To partially cope with this problem, there is a movement to connect all of the safety systems onto a single bus (see for example U.S. Pat. No. 6,326,704). Once again, the biggest problem with the reliability of airbag systems is the wiring and connectors. By practicing the teachings of this invention, one single pair of wires can be used to connect all of the airbag sensors and airbags together and to do so without the use of connectors. Thus, the reliability of the system is substantially improved and the reduced installation costs more than offsets the added cost of having a loosely coupled inductive network. With such a system, more and more of the airbag electronics can reside within or adjacent to the airbag module with the crash sensor and occupant information fed to the electronics modules for the deploy decision. Thus, all of the relevant information can reside on the vehicle safety or general bus with each airbag module making its own deploy decision locally. 3.2 Steering Wheel The steering wheel of an automobile is becoming more complex as more functions are incorporated utilizing switches and/or a mouse touch pad on the steering wheel or other haptic or non-haptic input device. Many vehicles have controls for heating and air conditioning, cruise control, radio, etc. Additionally, the airbag must have a very high quality connection so that it reliably deploys even when an accident is underway. This has resulted in the use of clockspring ribbon cables that make all of the electrical connections between the vehicle and the rotating steering wheel. The ribbon cable must at least able to carry sufficient current to reliably initiate airbag deployment even at very cold temperatures. This requires that the ribbon cable contain at least two heavy conductors to bring power to the airbag. Under the airbag network concept, a capacitor or battery is used within the airbag module and kept charged thereby significantly reducing the amount of current that must pass through the ribbon cable. Thus, the ribbon cable can be kept considerably smaller. An alternate and preferred solution uses the teachings of this invention to inductively couple the steering wheel with the vehicle thus eliminating all wires and connectors. All of the switch functions, control functions, and airbag functions are multiplexed on top of the inductive carrier frequency. This greatly simplifies the initial installation of the steering wheel onto the vehicle since the complicated ribbon cable is no longer necessary. Similarly, it reduces warranty repairs caused by people changing steering wheels without making sure that the ribbon cable is properly positioned. 3.3 Door Subsystem More and more electrical functions are also being placed into vehicle doors. This includes window control switches and motors as well as seat control switches, airbag crash sensors, etc. As a result the bundle of wires that must pass through the door edge and through the A-pillar has become a serious assembly and maintenance problem in the automotive industry. Using the teachings of this invention, the loosely coupled inductive system could pass anywhere near the door and an inductive pickup system placed on the other side where it obtains power and exchanges information when the mating surfaces are aligned. If these surfaces are placed in the A-pillar, then sufficient power can be available even when the door is open. Alternately, a battery or capacitive storage system can be provided in the door and the coupling can exist through the doorsill, for example. This eliminates the need for wires to pass through the door interface and greatly simplifies the assembly and installation of doors. It also greatly reduces warranty repairs caused by the constant movement of wires at the door and car body interface. 3.4 Blind Spot Monitor Many accidents are caused by a driver executing a lane change when there is another vehicle in his blind spot. As a result, several firms are developing blind spot monitors based on radar, optics, or passive infrared, to detect the presence of a vehicle in the driver's blind spot and to warn the driver should he attempt such a lane change. These blind spot monitors are typically placed on the outside of the vehicle near or on the side rear view mirrors. Since the device is exposed to rain, salt, snow etc., there is a reliability problem resulting from the need to seal the sensor and to permit wires to enter the sensor and also the vehicle. Special wire, for example, should be used to prevent water from wicking through the wire. These problems as well as similar problems associated with other devices which require electric power and which are exposed to the environment, such as forward-mounted airbag crash sensors, can be solved utilizing and inductive coupling techniques of this invention. 3.5 Truck to Trailer Power and Information Transfer. A serious source of safety and reliability problems results from the flexible wire connections that are necessary between a truck and a trailer. The need for these flexible wire connections and their associated connector problems can be eliminated using the inductive coupling techniques of this invention. In this case, the mere attachment of the trailer to the tractor automatically aligns an inductive pickup device on the trailer with the power lines imbedded in the fifth wheel. 3.6 Wireless Switches Switches in general do not consume power and therefore they can be implemented wirelessly according to the teachings of this invention in many different modes. For a simple on-off switch, a one bit RFID tag similar to what is commonly used for protecting against shoplifting in stores with a slight modification can be easily implemented. The RFID tag switch would contain its address and a single accessible bit permitting the device to be interrogated regardless of its location in the vehicle without wires. As the switch function becomes more complicated, additional power may be required and the options for interrogation become more limited. For a continuously varying switch, for example the volume control on a radio, it may be desirable to use a more complicated design where an inductive transfer of information is utilized. On the other hand, by using momentary contact switches that would set the one bit on only while the switch is activated and by using the duration of activation, volume control type functions can still be performed even though the switch is remote from the interrogator. This concept then permits the placement of switches at arbitrary locations anywhere in the vehicle without regard to the placement of wires. Additionally, multiple switches can be easily used to control the same device or a single switch can control many devices. For example, a switch to control the forward and rearward motion of the driver seat can be placed on the driver door-mounted armrest and interrogated by RFID reader located in the headliner of the vehicle. The interrogator periodically monitors all RFID switches located in the vehicle which may number over 100. If the driver armrest switch is depressed and the switch bit is changed from 0 to 1, the reader knows based on the address or identification number of the switch that the driver intends to operate his seat in a forward or reverse manner. A signal is then sent over the inductive power transfer line to the motor controlling the seat and the motor is commanded to move the seat either forward based on one switch ID or backward based on another switch ID. Thus, the switch in the armrest would actually contain two identification RFIDs, one for forward movement of seat and one for rearward movement of the seat. As soon the driver ceases operating the switch, the switch state returns to 0 and a command is sent to the motor to stop moving the seat. The RFID can be passive or active. By this process as taught by this invention, all of the 100 or so switches and other simple sensors can become wireless devices and vastly reduce the number of wires in a vehicle and increase the reliability and reduce warranty repairs. One such example is the switch that determines whether the seatbelt is fastened which can now be a wireless switch. 3.7 Wireless Lights In contrast to switches, lights require power. The power required generally exceeds that which can be easily transmitted by RF or capacitive coupling. For lights to become wireless, therefore, inductive coupling or equivalent is required. Now, however, it is no longer necessary to have light sockets, wires and connectors. Each light bulb could be outfitted with an inductive pickup device and a microprocessor. The microprocessor listens to the information coming over the inductive pickup line and when it recognizes its address, it activates an internal switch which turns on the light. The light bulb becomes a totally sealed, self-contained unit with no electrical connectors or connections to the vehicle. It is automatically connected by mounting in a holder and by its proximity, which can be as far away as several inches, to the inductive power line. It has been demonstrated that power transfer efficiencies of up to about 99 percent can be achieved by this system and power levels exceeding about 1 kW can be transferred to a device. This invention therefore considerably simplifies the mounting of lights in a vehicle since the lights are totally self-contained and not plugged into the vehicle power system. Problems associated with sealing the light socket from the environment disappear vastly simplifying the installation of headlights, for example, into the vehicle. The skin of the vehicle need not contain any receptacles for a light plug and therefore there is no need to seal the light bulb edges to prevent water from entering behind the light bulb. Thus, the reliability of vehicle exterior lighting systems is significantly improved. Similarly, the ease with which light bulbs can be changed when they bum out is greatly simplified since the complicated mechanisms for sealing the light bulb into the vehicle are no longer necessary. Although headlights were discussed, the same principles apply to all other lights mounted on a vehicle exterior. Since it is contemplated that the main power transfer wire pair will travel throughout the automobile in a single branched loop, several light bulbs can be inductively attached to the inductive wire power supplier by merely locating a holder for the sealed light bulb within a few inches of the wire. Once again, no electrical connections are required. Consider for example the activation of the right turn signal. The microprocessor associated with the turn switch on the steering column is programmed to transmit the addresses of the right front and rear turn light bulbs to turn them on. A fraction of a second later, the microprocessor sends a signal over the inductive power transfer line to turn the light bulbs off. This is repeated for as long as the turn signal switch is placed in the activation position for a right turn. The right rear turn signal light bulb receives a message with its address and a bit set for the light to be turned on and it responds by so doing and similarly, when the signal is received for turning the light off. Once again, all such transmissions occur over a single power and information inductive line and no wire connections are made to the light bulb. In this example, all power and information is transferred inductively. 3.8 Keyless Entry The RFID technology is particularly applicable to keyless entry. Instead of depressing a button on a remote vehicle door opener, the owner of vehicle need only carry an RFID card in his pocket. Upon approaching the vehicle door, the reader located in the vehicle door, activates the circuitry in the RFID card and receives the identification number, checks it and unlocks the vehicle if the code matches. It can even open the door or trunk based on the time that the driver stands near the door or trunk. Simultaneously, the vehicle now knows that this is driver No. 3, for example, and automatically sets the seat position, headrest position, mirror position, radio stations, temperature controls and all other driver specific functions including the positions of the petals to adapt the vehicle to the particular driver. When the driver sits in the seat, no ignition key is necessary and by merely depressing a switch which can be located anywhere in the vehicle, on the armrest for example, the vehicle motor starts. The switch can be wireless and the reader or interrogator which initially read the operator's card can be connected inductively to the vehicle power system. U.S. Pat. No. 5,790,043 describes the unlocking of a door based on a transponder held by a person approaching the door. By adding the function of measuring the distance to the person, by use of the backscatter from the transponder antenna for example, the distance from the vehicle-based transmitter and the person can be determined and the door opened when the person is within 5 feet, for example, of the door as discussed elsewhere herein. 3.9 In-Vehicle Mesh Network, Intra-Vehicle Communications The use of wireless networks within a vehicle has been discussed elsewhere herein. Of particular interest here is the use of a mesh network (or mesh) wherein the various wireless elements are connected via a mesh such that each device can communicate with each other to thereby add information that might aid a particular node. In the simplest case, nodes on the mesh can merely aid in the transfer of information to a central controller. In more advanced cases, the temperature monitored by one node can be used by other nodes to compensate for the effects of temperature of the node operation. In another case, the fact that a node has been damaged or is experiencing acceleration can be used to determine the extent of and to forecast the severity of an accident. Such a mesh network can operate in the ultra wideband mode. 3.10 Road Conditioning Sensing—Black Ice Warning A frequent cause of accidents is the sudden freezing of roadways or bridge surfaces when the roadway is wet and temperatures are near freezing. Sensors exist that can detect the temperature of the road surface within less than one degree. These sensors can be mounted in locations where they have a clear view of the road and thus they are susceptible to assault from rain, snow, ice, salt etc. The reliability of connecting these sensors into the vehicle power and information system is thus compromised. Using the teachings of this invention, black ice warning sensors can be mounted externally to the vehicle and coupled into the vehicle power and information system inductively, thus removing a significant cause of failure of such sensors. The use of appropriate cameras and sensors along with multispectral analysis of road surfaces can be particularly useful to discover icing. Similar sensors can also used to detect the type of roadway on which the car is traveling. Gravel roads, for example, have typically a lower effective coefficient of friction than do concrete roads. Knowledge of the road characteristics can provide useful information to the vehicle control system and, for example, warn the driver when the speed driven is above what is safe for the road conditions, including the particular type of roadway. 3.11 Antennas Including Steerable Antennas As discussed above, the antennas used in the systems disclosed herein can contribute significantly to the operation of the systems. In the simplest case, a silicon or gallium arsenide (for higher frequencies) element can be placed at an antenna to process the returned signal as needed. High gain antennas such as the yagi antenna or steerable antennas such as electronically controllable (or tunable) dielectric constant phased array antennas are also contemplated. For steerable antennas, reference is made to U.S. Pat. No. 6,452,565 “Steerable-beam multiple-feed dielectric resonator antenna”. Also contemplated are variable slot antennas and Rotman lenses. All of these plus other technologies go under the heading of smart antennas and all such antennas are contemplated herein. The antenna situation can be improved as the frequency increases. Currently, SAW devices are difficult to make that operate much above about 500 MHz. It is expected that as lithography systems improve that eventually these devices will be made to operate in the GHz range permitting the use of antennas that are more directional. 3.12 Other Miscellaneous Sensors Many new sensors are now being adapted to an automobile to increase the safety, comfort and convenience of vehicle occupants. Each of the sensors currently requires separate wiring for power and information transfer. Under the teachings of this invention, these separate wires would become unnecessary and sensors could be added at will to the automobile at any location within a few inches of the inductive power line system or, in some cases, within view of an RF interrogator. Even sensors that were not contemplated by the vehicle manufacturer can be added later with a software change to the appropriate vehicle CPU. Such sensors include heat load sensors that measure the sunlight coming in through the windshield and adjust the environmental conditions inside the vehicle or darken the windshield to compensate. Seatbelt sensors that indicate that the seatbelt is buckled can now also use RFID technology as can low power microphones. Door-open or door-ajar sensors also can use the RFID technology and would not need to be placed near an inductive power line. Gas tank fuel level and other fluid level sensors which do not require external power and are now possible thus eliminating any hazard of sparks igniting the fuel in the case of a rear impact accident which ruptures the fuel tank, for example. Capacitive proximity sensors that measure the presence of a life form within a few meters of the automobile can be coupled wirelessly to the vehicle. Cameras or other vision or radar sensors that can be mounted external to the vehicle and not require unreliable electrical connections to the vehicle power system permitting such sensors to be totally sealed from the environment are also now possible. Such sensors can be based on millimeter wave radar, passive or active infrared, or optical or any other portion of the electromagnetic spectrum that is suitable for the task. Radar or ultrasonic backup sensors or rear impact anticipatory sensors also are now feasible with significantly greater reliability. Previously, the use of radio frequency to interrogate an RFID tag has been discussed. Other forms of electromagnetic radiation are possible. For example, an infrared source can illuminate an area inside the vehicle and a pin diode or CMOS camera can receive reflections from corner cube reflectors located on objects that move within the vehicle. These objects would include items such as the seat, seatback, and headrest. Through this technique, the time of flight, by pulse or phase lock loop technologies, of the modulated IR radiation can be measured to each of the corner cube reflectors and the distance to the reflector thereby determined. The above discussion has concentrated on applications primarily inside of the vehicle (although mention is often made of exterior monitoring applications). There are also a significant number of applications concerning the interaction of a vehicle with its environment. Although this might be construed as a deviation from the primary premise of this invention, which is that the device is either powerless in the sense that no power is required other than perhaps that which can be obtained from a radio frequency signal or a powered device and where the power is obtained through induction coupling, it is encompassed within the invention. When looking exterior to the vehicle, devices that interact vehicle may be located sufficiently far away that they will require power and that power cannot be obtained from the automobile. In the discussion below, two types of such devices will be considered, the first type which does not require infrastructure-supplied power and the second which does. A rule of thumb is that an RFID tag of normal size that is located more than one meter away from the reader or interrogator must have a battery. Exceptions to this involve cases where the only information that is transferred is due to the reflection off of a radar reflector-type device and for cases where the tag is physically larger. For those cases, a purely passive RFID can be five and sometimes more meters away from the interrogator. Nevertheless, we shall assume that if the device is more than a few meters away that the device must contain some kind of external power supply. The first interesting application is a low-cost form of adaptive cruise control or forward collision avoidance system. In this case, a purely passive RFID tag would be placed on every rear license plate in a particular geographical area, such as a state. The subject vehicle would contain two readers, one on the forward left side of the vehicle and one on the forward right side. Upon approaching the rear of a car having the RFID license plate, the interrogators in the vehicle would be able to determine the distance, by way of reflected signal time of flight, from each reader to the license plate transducer. If the license plate RFID is passive, then the range is limited to about 5 meters depending on the size of the tag. Nevertheless, this will be sufficient to determine that there is a vehicle in front of or to the right or left side of the subject vehicle. If the relative velocity of the two vehicles is such that a collision will occur, the subject vehicle can automatically have its speed altered so as to prevent the collision, typically a rear end collision. Alternately, the front of the vehicle can have two spaced-apart tags in which case, a single interrogator could suffice. Systems are under development that will permit an automobile to determine its absolute location on the surface of the earth. These systems are being developed in conjunction with intelligent transportation systems. Such location systems are frequently based on differential GPS (DGPS). One problem with such systems is that the appropriate number of GPS satellites is not always within view of the automobile. For such cases, it is necessary to have an earth-based system which will provide the information to the vehicle permitting it to absolutely locate itself within a few centimeters. One such system can involve the use of RFID tags placed above, adjacent or below the surface of the highway. For the cases where the RFID tags are located more than a few meters from the vehicle, a battery will probably be required and this will be discussed below. For the systems without batteries, such as placing the RFID tag in the concrete, with two readers located one on each side of the vehicle, the location of the tag embedded in the concrete can be precisely determine based on the time of flight of the radar pulse from the readers to the tag and back. Using this method, the precise location of the vehicle relative to a tag within a few centimeters can be readily determined and since the position of the tag will be absolutely known by virtue of an in-vehicle resident digital map, the position of the vehicle can be absolutely determined regardless of where the vehicle is. For example, if the vehicle is in a tunnel, then it will know precisely its location from the RFID pavement embedded tags. It is also possible to determine the relative velocity of the vehicle relative to the RFID tag using the Doppler Effect based on the reflected signals. For tags located on license plates or elsewhere on the rear of vehicles, the closing velocity of the two vehicles can be determined and for tags located in or adjacent to the highway pavement, the velocity of the vehicle can be readily determined. The velocity can in both cases be determined based on differentiating two distance measurements. In many cases, it may be necessary to provide power to the RFID tag since the distance to the vehicle will exceed a few meters. This is currently being used in reverse for automatic tolling situations where the RFID tag is located on the vehicle and interrogated using readers located at the toll both. When the RFID tag to be interrogated by vehicle-mounted readers is more than a few meters from the vehicle, the tag in many cases must be supplied with power. This power can come from a variety of sources including a battery which is part of the device, direct electrical connections to a ground wire system, solar batteries, generators that generate power from vehicle or component vibration, or inductive energy transfer from a power line. For example, if an RFID tag were to be placed on a light post in downtown Manhattan, sufficient energy could be obtained from an inductive pickup from the wires used to power the light to recharge a battery in the RFID. Thus, when the lights are turned on at night, the RFID battery could be recharged sufficiently to provide power for operation 24 hours a day. In other cases, a battery would be included in the device and replacement of the battery would be necessitated periodically, perhaps once every two years. An alternate approach to having a vehicle transmit a pulse to the tag and wait for a response, would be to have the tag periodically broadcast a few waves of information at precise timing increments. Then, the vehicle with two receivers could locate itself accurately relative to the earth-based transmitter. For example, in downtown Manhattan it would be difficult to obtain information from satellites that are constantly blocked by tall buildings. Nevertheless, inexpensive transmitters could be placed on a variety of lampposts that would periodically transmit a pulse to all vehicles in the vicinity. Such a system could be based on a broadband micropower impulse radar system as disclosed in several U.S. patents. Alternately, a narrow band signal could be used. Once again, although radar type microwave pulses have been discussed, other portions of the electromagnetic spectrum could be utilized. For example, a vehicle could send a beam of modulated infrared toward infrastructure-based devices such as poles which contain corner reflectors. The time of flight of IR radiation from the vehicle to the reflectors can be accurately measured and since the vehicle would know, based on accurate maps, where the reflector is located, there is the little opportunity for an error. The invention is also concerned with wireless devices that contain transducers. An example is a temperature transducer coupled with appropriate circuitry which is capable of receiving power either inductively or through radio frequency energy transfer or even, and some cases, capacitively. Such temperature transducers may be used to measure the temperature inside the passenger compartment or outside of the vehicle. They also can be used to measure the temperature of some component in the vehicle, e.g., the tire. A distinctive feature of some embodiments of this invention is that such temperature transducers are not hard-wired into the vehicle and do not rely solely on batteries. Such temperature sensors have been used in other environments such as the monitoring of the temperature of domestic and farm animals for health monitoring purposes. Upon receiving power inductively or through the radio frequency energy transfer, the temperature transducer conducts its temperature measurement and transmits the detected temperature to a process or central control module in the vehicle. The wireless communication within a vehicle can be accomplished in several ways. The communication can be through the same path that supplies power to the device, or it can involve the transmission of waves that are received by another device in the vehicle. These waves can be either electromagnetic (microwave, infrared, etc) or ultrasonic. Many other types of transducers or sensors can be used in this manner. The distance to an object a vehicle can be measured using a radar reflector type RFID (Radio Frequency Identification) tag which permits the distance to the tag to be determined by the time of flight of radio waves. Another method of determining distance to an object can be through the use of ultrasound wherein the device is commanded to emit an ultrasonic burst and the time required for the waves to travel to a receiver is an indication of the displacement of the device from the receiver. Although in most cases the communication will take place within the vehicle, and some cases such as external temperature transducers or tire pressure transducers, the source of transmission will be located outside of the compartment of the vehicle. A discussion of RFID technology including its use for distance measurement is included in the RFID Handbook, by Klaus Finkenzeller, John Wiley & Sons, New York 1999. In its simplest form the invention can involve a single transducer and system for providing power and receiving information. An example of such a device would be an exterior temperature monitor which is placed outside of the vehicle and receives its power and transmits its information through the windshield glass. At the other extreme, a pair of parallel wires carrying high frequency alternating current can travel to all parts of the vehicle where electric power is needed. In this case, every device could be located within a few inches of this wire pair and through an appropriately designed inductive pickup system, each device receives the power for operation inductively from the wire pair. A system of this type which is designed for use in powering vehicles is described in several U.S. patents listed above. In this case, all sensors and actuators on the vehicle could be powered by the inductive power transfer system. The communication with these devices could either be over the same system or, alternately, could be take place via RF or other similar communication system. If the communication takes place either by RF or over a modulated wire system, a protocol such as the Bluetooth™ protocol can be used. Other options include the Ethernet and token ring protocols. The above system technology is frequently referred to as loosely coupled inductive systems. Such systems have been used for powering a vehicle down a track or roadway but have not been used within the vehicle. The loosely coupled inductive system makes use of high frequency (typically 10,000 Hz) and resonant circuits to achieve a power transfer approaching 99 percent efficiency. The resonant system is driven using a switching amplifier. As discussed herein, this is believed to be the first example of a high frequency power system for use within vehicles. Every device that utilizes the loosely coupled inductive system would contain a microprocessor and thus would be considered a smart device. This includes every light, switch, motor, transducer, sensor etc. Each device would have an address and would respond only to information containing its address. It is now contemplated that the power systems for next generation automobiles and trucks will change from the current standard of 12 volts to a new standard of 42 volts. The power generator or alternator in such vehicles will produce alternating current and thus will be compatible with the system described herein wherein all power within the vehicle will be transmitted using AC. It is contemplated that some devices will require more power then can be obtained instantaneously from the inductive, capacitive or radio frequency source. In such cases, batteries, capacitors or ultra-capacitors may be used directly associated with a particular device to handle peak power requirements. Such a system can also be used when the device is safety critical and there is a danger of disruption of the power supply during a vehicle crash, for example. In general, the battery or capacitor would be charged when the device is not being powered. In some cases, the sensing device may be purely passive and require no power. One such example is when an infrared or optical beam of energy is reflected off of a passive reflector to determine the distance to that reflector. Another example is a passive reflective RFID tag. As noted above, several U.S. patents describe arrangements for monitoring the pressure inside a rotating tire and to transmit this information to a display inside the vehicle. A preferred approach for monitoring the pressure within a tire is to instead monitor the temperature of the tire using a temperature sensor and associated power supplying circuitry as discussed above and to compare that temperature to the temperature of other tires on the vehicle, as discussed above. When the pressure within a tire decreases, this generally results in the tire temperature rising if the vehicle load is being carried by that tire. In the case where two tires are operating together at the same location such as on a truck trailer, just the opposite occurs. That is, the temperature of the fully inflated tire increases since it is now carrying more load than the partially inflated tire. 4. Summary Among the inventions disclosed above is an arrangement for obtaining and conveying information about occupancy of a passenger compartment of a vehicle comprises at least one wave-receiving sensor for receiving waves from the passenger compartment, a generating system coupled to the wave-receiving sensor(s) for generating information about the occupancy of the passenger compartment based on the waves received by the wave-receiving sensor(s) and a communications system coupled to the generating system for transmitting the information about the occupancy of the passenger compartment. As such, response personnel can receive the information about the occupancy of the passenger compartment and respond appropriately, if necessary. There may be several wave-receiving sensors and they may be, e.g., ultrasonic wave-receiving sensors, electromagnetic wave-receiving sensors, capacitance or electric field sensors, or combinations thereof The information about the occupancy of the passenger compartment can include the number of occupants in the passenger compartment, as well as whether each occupant is moving non-reflexively and breathing. A transmitter may be provided for transmitting waves into the passenger compartment such that each wave-receiving sensor receives waves transmitted from the transmitter and modified by passing into and at least partially through the passenger compartment. One or more memory units may be coupled to the generating system for storing the information about the occupancy of the passenger compartment and to the communications system. The communications system then can interrogate the memory unit(s) upon a crash of the vehicle to thereby obtain the information about the occupancy of the passenger compartment. In one particularly useful embodiment, the health state of at least one occupant is determined by a sensor or sensor system, e.g., by a heartbeat sensor, a motion sensor such as a micropower impulse radar sensor for detecting motion of the at least one occupant and motion sensor for determining whether the occupant(s) is/are breathing, and provided to the communications system. The communications system can interrogate the health state determining sensor(s) upon a crash of the vehicle to thereby obtain and transmit the health state of the occupant(s). The health state determining sensor(s) can also comprise a chemical sensor for analyzing the amount of carbon dioxide in the passenger compartment or around the at least one occupant or for detecting the presence of blood in the passenger compartment. Movement of the occupant can be determined by monitoring the weight distribution of the occupant(s), or an analysis of waves from the space occupied by the occupant(s). Each wave-receiving sensor generates a signal representative of the waves received thereby and the generating system may comprise a processor for receiving and analyzing the signal from the wave-receiving sensor in order to generate the information about the occupancy of the passenger compartment. The processor can comprise pattern recognition means for classifying an occupant of the seat so that the information about the occupancy of the passenger compartment includes the classification of the occupant. The wave-receiving sensor may be a micropower impulse radar sensor adapted to detect motion of an occupant whereby the motion of the occupant or absence of motion of the occupant is indicative of whether the occupant is breathing. As such, the information about the occupancy of the passenger compartment generated by the generating means is an indication of whether the occupant is breathing. Also, the wave-receiving sensor may generate a signal representative of the waves received thereby and the generating means receive this signal over time and determine whether any occupants in the passenger compartment are moving. As such, the information about the occupancy of the passenger compartment generated by the generating system includes the number of moving and non-moving occupants in the passenger compartment. In another embodiment of the component diagnostic system discussed above, at least one sensor detects a signal containing information as to whether the component is operating normally or abnormally and outputs a corresponding electrical signal. A processor or other computing device is coupled to the sensor(s) for receiving and processing the electrical signal(s) and for determining if the component is operating abnormally based thereon. The processor preferably comprises or embodies a pattern recognition algorithm for analyzing a pattern within the signal detected by each sensor. An output device (or multiple output devices) is coupled to the processor for affecting another system within the vehicle if the component is operating abnormally. The other system may be a display as mentioned above or a warning device. In other embodiments disclosed above, the state of the entire vehicle is diagnosed whereby two or more sensors, preferably acceleration sensors and gyroscopes, detect the state of the vehicle and if the state is abnormal, an output system is coupled to the processor for affecting another system in the vehicle. The another system may be the steering control system, the brake system, the accelerator or the frontal or side occupant protection system. An exemplifying control system for controlling a part of the vehicle in accordance with the invention thus comprises a plurality of sensor systems mounted at different locations on the vehicle, each sensor system providing a measurement related to a state of the sensor system or a measurement related to a state of the mounting location, and a processor coupled to the sensor systems and arranged to diagnose the state of the vehicle based on the measurements of the sensor system, e.g., by the application of a pattern recognition technique. The processor controls the part based at least in part on the diagnosed state of the vehicle. At least one of the sensor systems may be a high dynamic range accelerometer or a sensor selected from a group consisting of a single axis acceleration sensor, a double axis acceleration sensor, a triaxial acceleration sensor and a gyroscope, and may optionally include an RFID response unit. The gyroscope may be a MEMS-IDT gyroscope including a surface acoustic wave resonator which applies standing waves on a piezoelectric substrate. If an RFID response unit is present, the control system would then comprise an RFID interrogator device which causes the RFID response unit(s) to transmit a signal representative of the measurement of the sensor system associated therewith to the processor. The state of the vehicle diagnosed by the processor may be the vehicle's angular motion, angular acceleration and/or angular velocity. As such, the steering system, braking system or throttle system may be controlled by the processor in order to maintain the stability of the vehicle. The processor can also be arranged to control an occupant restraint or protection device in an attempt to minimize injury to an occupant. The state of the vehicle diagnosed by the processor may also be a determination of a location of an impact between the vehicle and another object. In this case, the processor can forecast the severity of the impact using the force/crush properties of the vehicle at the impact location and control an occupant restraint or protection device based at least in part on the severity of the impact. The system can also include a weight sensing system coupled to a seat in the vehicle for sensing the weight of an occupying item of the seat. The weight sensing system is coupled to the processor whereby the processor controls deployment or actuation of the occupant restraint or protection device based on the state of the vehicle and the weight of the occupying item of the seat sensed by the weight sensing system. A display may be coupled to the processor for displaying an indication of the state of the vehicle as diagnosed by the processor. A warning device may be coupled to the processor for relaying a warning to an occupant of the vehicle relating to the state of the vehicle as diagnosed by the processor. Further, a transmission device may be coupled to the processor for transmitting a signal to a remote site relating to the state of the vehicle as diagnosed by the processor. The state of the vehicle diagnosed by the processor may include angular acceleration of the vehicle whereby angular velocity and angular position or orientation are derivable from the angular acceleration. The processor can then be arranged to control the vehicle's navigation system based on the angular acceleration of the vehicle. Another control system for controlling a part of the vehicle in accordance with the invention comprises a plurality of sensor systems mounted on the vehicle, each providing a measurement of a state of the sensor system or a state of the mounting location of the sensor system and generating a signal representative of the measurement, and a pattern recognition system for receiving the signals from the sensor systems and diagnosing the state of the vehicle based on the measurements of the sensor systems. The pattern recognition system generates a control signal for controlling the part based at least in part on the diagnosed state of the vehicle. The pattern recognition system may comprise one or more neural networks. The features of the control system described above may also be incorporated into this control system to the extent feasible. The state of the vehicle diagnosed by the pattern recognition system may include a state of an abnormally operating component whereby the pattern recognition system is designed to identify a potentially malfunctioning component based on the state of the component measured by the sensor systems and determine whether the identified component is operating abnormally based on the state of the component measured by the sensor systems. In one preferred embodiment, the pattern recognition system may comprise a neural network system and the state of the vehicle diagnosed by the neural network system includes a state of an abnormally operating component. The neural network system includes a first neural network for identifying a potentially malfunctioning component based on the state of the component measured by the sensor systems and a second neural network for determining whether the identified component is operating abnormally based on the state of the component measured by the sensor systems. Modular neural networks can also be used whereby the neural network system includes a first neural network arranged to identify a potentially malfunctioning component based on the state of the component measured by the sensor systems and a plurality of additional neural networks. Each of the additional neural networks is trained to determine whether a specific component is operating abnormally so that the measurements of the state of the component from the sensor systems are input into that one of the additional neural networks trained on a component which is substantially identical to the identified component. Another method for controlling a part of the vehicle comprises the steps of mounting a plurality of sensor systems on the vehicle, measuring a state of the sensor system or a state of the respective mounting location of the sensor system, generating signals representative of the measurements of the sensor systems, inputting the signals into a pattern recognition system to obtain a diagnosis of the state of the vehicle and controlling the part based at least in part on the diagnosis of the state of the vehicle. In one notable embodiment, a potentially malfunctioning component is identified by the pattern recognition system based on the states measured by the sensor systems and the pattern recognition system determine whether the identified component is operating abnormally based on the states measured by the sensor systems. If the pattern recognition system comprises a neural network system, identification of the component entails inputting the states measured by the sensor systems into a first neural network of the neural network system and the determination of whether the identified component is operating abnormally entails inputting the states measured by the sensor systems into a second neural network of the neural network system. A modular neural network system can also be applied in which the states measured by the sensor systems are input into a first neural network and a plurality of additional neural networks are provided, each being trained to determine whether a specific component is operating abnormally, whereby the states measured by the sensor systems are input into that one of the additional neural networks trained on a component which is substantially identical to the identified component. Also disclosed above is a vehicle including a diagnostic system arranged to diagnose the state of the vehicle or the state of a component of the vehicle and generate an output indicative or representative thereof and a communications device coupled to the diagnostic system and arranged to transmit the output of the diagnostic system. The diagnostic system may comprise a plurality of vehicle sensors mounted on the vehicle, each sensor providing a measurement related to a state of the sensor or a measurement related to a state of the mounting location, and a processor coupled to the sensors and arranged to receive data from the sensors and process the data to generate the output indicative or representative of the state of the vehicle or the state of a component of the vehicle. The sensors may be wirelessly coupled to the processor and arranged at different locations on the vehicle. The processor may embody a pattern recognition algorithm trained to generate the output from the data received from the sensors, such as a neural network, fuzzy logic, sensor fusion and the like, and be arranged to control one or more parts of the vehicle based on the output indicative or representative of the state of the vehicle or the state of a component of the vehicle. The state of the vehicle can include angular motion of the vehicle. A display may be arranged in the vehicle in a position to be visible from the passenger compartment. Such as display is coupled to the diagnostic system and arranged to display the diagnosis of the state of the vehicle or the state of a component of the vehicle. A warning device may also be coupled to the diagnostic system for relaying a warning to an occupant of the vehicle relating to the state of the vehicle or the state of the component of the vehicle as diagnosed by the diagnostic system. The communications device may comprise a cellular telephone system including an antenna as well as other similar or different electronic equipment capable of transmitting a signal to a remote location, optionally via a satellite. Transmission via the Internet, i.e., to a web site or host computer associated with the remote location is also a possibility for the invention. If the vehicle is considered it sown site, then the transmission would be a site-to-site transmission via the Internet. An occupant sensing system can be provided to determine at least one property or characteristic of occupancy of the vehicle. In this case, the communications device is coupled to the occupant sensing system and transmits the determined property or characteristic of occupancy of the vehicle. In a similar manner, at least one environment sensor can be provided, each sensing a state of the environment around the vehicle. In this case, the communications device is coupled to the environment sensor(s) and transmits the sensed state of the environment around the vehicle. Moreover, a location determining system, optionally incorporating GPS technology, could be provided on the vehicle to determine the location of the vehicle and transmitted to the remote location along with the diagnosis of the state of the vehicle or its component. A memory unit may be coupled to the diagnostic system and the communications device. The memory unit receives the diagnosis of the state of the vehicle or the state of a component of the vehicle from the diagnostic system and stores the diagnosis. The communications device then interrogates the memory unit to obtain the stored diagnosis to enable transmission thereof, e.g., at periodic intervals. The sensors may be any known type of sensor including, but not limited to, a single axis acceleration sensor, a double axis acceleration sensor, a triaxial acceleration sensor and a gyroscope. The sensors may include an RFID response unit and an RFID interrogator device which causes the RFID response units to transmit a signal representative of the measurement of the associated sensor to the processor. In addition to or instead or an RFID-based system, one or more SAW sensors can be arranged on the vehicle, each receiving a signal and returning a signal modified by virtue of the state of the sensor or the state of the mounting location of the sensor. For example, the SAW sensor can measure temperature and/or pressure of a component of the vehicle or in a certain location or space on the vehicle, or the concentration and/or presence of a chemical. A method for monitoring a vehicle comprises diagnosing the state of the vehicle or the state of a component of the vehicle by means of a diagnostic system arranged on the vehicle, generating an output indicative or representative of the diagnosed state of the vehicle or the diagnosed state of the component of the vehicle, and transmitting the output to a remote location. Transmission of the output to a remote location may entail arranging a communications device comprising a cellular telephone system including an antenna on the vehicle. The output may be to a satellite for transmission from the satellite to the remote location. The output could also be transmitted via the Internet to a web site or host computer associated with the remote location. It is important to note that raw sensor data is not transmitted from the vehicle the remote location for analysis and processing by the devices and/or personnel at the remote location. Rather, in accordance with the invention, a diagnosis of the vehicle or the vehicle component is performed on the vehicle itself and this resultant diagnosis is transmitted. The diagnosis of the state of the vehicle may encompass determining whether the vehicle is stable or is about to rollover or skid and/or determining a location of an impact between the vehicle and another object. A display may be arranged in the vehicle in a position to be visible from the passenger compartment in which case, the state of the vehicle or the state of a component of the vehicle is displayed thereon. Further, a warning can be relayed to an occupant of the vehicle relating to the state of the vehicle. In addition to the transmission of vehicle diagnostic information obtained by analysis of data from sensors performed on the vehicle, at least one property or characteristic of occupancy of the vehicle may be determined (such as the number of occupants, the status of the occupants-breathing or not, injured or not, etc.) and transmitted to a remote location, the same or a different remote location to which the diagnostic information is sent. The information can also be sent in a different manner than the information relating to the diagnosis of the vehicle. Additional information for transmission by the components on the vehicle may include a state of the environment around the vehicle, for example, the temperature, pressure, humidity, etc. in the vicinity of the vehicle, and the location of the vehicle. A memory unit may be provided in the vehicle, possibly as part of a microprocessor, and arranged to receive the diagnosis of the state of the vehicle or the state of the component of the vehicle and store the diagnosis. As such, this memory unit can be periodically interrogated to obtain the stored diagnosis to enable transmission thereof Diagnosis of the state of the vehicle or the state of the component of the vehicle may entail mounting a plurality of sensors on the vehicle, measuring a state of each sensor or a state of the mounting location of each sensor and diagnosing the state of the vehicle or the state of a component of the vehicle based on the measurements of the state of the sensors or the state of the mounting locations of the sensors. These functions can be achieved by a processor which is wirelessly coupled to the sensors. The sensors can optionally be provided with RFID technology, i.e., an RFID response unit, whereby an RFID interrogator device is mounted on the vehicle and signals transmitted via the RFID interrogator device causes the RFID response units of any properly equipped sensors to transmit a signal representative of the measurements of that sensor to the processor. SAW sensors can also be used, in addition to or instead of RFID-based sensors. One embodiment of the diagnostic module in accordance with the invention utilizes information which already exists in signals emanating from various vehicle components along with sensors which sense these signals and, using pattern recognition techniques, compares these signals with patterns characteristic of normal and abnormal component performance to predict component failure, vehicle instability or a crash earlier than would otherwise occur if the diagnostic module was not utilized. If fully implemented, this invention is a total diagnostic system of the vehicle. In most implementations, the module is attached to the vehicle and electrically connected to the vehicle data bus where it analyzes data appearing on the bus to diagnose components of the vehicle. In some implementations, multiple distributed accelerometers and/or microphones are present on the vehicle and, in some cases, some of the sensors will communicate using wireless technology to the vehicle bus or directly to the diagnostic module. Although several preferred embodiments are illustrated and described above, there are possible combinations using other geometries, sensors, materials and different dimensions for the components that perform the same functions. This invention is not limited to the above embodiments and should be determined by the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Set below is some relevant background relating to the invention. Additional background is found in the parent application, U.S. patent application Ser. No. 10/701,361, and is incorporated by reference herein. 1. Diagnostics 1.1 General Diagnostics When a vehicle component begins to fail, the repair cost is frequently minimal if the impending failure of the component is caught early, but increases as the repair is delayed. Sometimes, if a component in need of repair is not caught in a timely manner, the component, and particularly the impending failure thereof, can cause other components of the vehicle to deteriorate. One example is where the water pump fails gradually until the vehicle overheats and blows a head gasket. Another example is when a tire gradually loses air until it heats up, fails and causes an accident. It is desirable, therefore, to determine that a vehicle component is about to fail as early as possible so as to minimize the probability of a breakdown and the resulting repair costs. There are various gages on an automobile which alert the driver to various vehicle problems. For example, if the oil pressure drops below some predetermined level, the driver is warned to stop his vehicle immediately. Similarly, if the coolant temperature exceeds some predetermined value, the driver is also warned to take immediate corrective action. In these cases, the warning often comes too late as most vehicle gages alert the driver after he or she can conveniently solve the problem. Thus, what is needed is a component failure warning system that alerts the driver to the impending failure of a component sufficiently in advance of the time when the problem gets to a catastrophic point. Some astute drivers can sense changes in the performance of their vehicle and correctly diagnose that a problem with a component is about to occur. Other drivers can sense that their vehicle is performing differently but they don't know why or when a component will fail or how serious that failure will be, or possibly even what specific component is the cause of the difference in performance. The invention disclosed herein will, in most cases, solve this problem by predicting component failures in time to permit maintenance and thus prevent vehicle breakdowns. Presently, automobile sensors in use are based on specific predetermined or set levels, such as the coolant temperature or oil pressure, whereby an increase above the set level or a decrease below the set level will activate the sensor, rather than being based on changes in this level over time. The rate at which coolant heats up, for example, can be an important clue that some component in the cooling system is about to fail. There are no systems currently on automobiles to monitor the numerous vehicle components over time and to compare component performance with normal performance. Nowhere in the vehicle is the vibration signal of a normally operating front wheel stored, for example, or for that matter, any normal signal from any other vehicle component. Additionally, there is no system currently existing on a vehicle to look for erratic behavior of a vehicle component and to warn the driver or the dealer that a component is misbehaving and is therefore likely to fail in the very near future. Basically, the operating of an automobile should be a process not a project. A purpose of this invention is to eliminate breakdowns through identifying potential component failures before they occur so that they can be repaired in a timely manner. Another purpose is to notify the operator and a service facility of the pending failure so that it can be prevented. Sometimes, when a component fails, a catastrophic accident results. In the Firestone tire case, for example, over 100 people were killed when a tire of a Ford Explorer blew out which caused the Ford Explorer to rollover. Similarly, other component failures can lead to loss of control of the vehicle and a subsequent accident. It is thus important to accurately forecast that such an event will take place but furthermore, for those cases where the event takes place suddenly without warning, it is also important to diagnose the state of the entire vehicle, which in some cases can lead to automatic corrective action to prevent unstable vehicle motion or rollovers resulting in an accident. Finally, an accurate diagnostic system for the entire vehicle can determine much more accurately the severity of an automobile crash once it has begun by knowing where the accident is taking place on the vehicle (e.g., the part of or location on the vehicle which is being impacted by an object) and what is colliding with the vehicle based on a knowledge of the force deflection characteristics of the vehicle at that location. Therefore, in addition to a component diagnostic, the teachings of this invention also provide a diagnostic system for the entire vehicle prior to and during accidents. In particular, this invention is concerned with the simultaneous monitoring of multiple sensors on the vehicle so that the best possible determination of the state of the vehicle can be determined. Current crash sensors operate independently or at most one sensor may influence the threshold at which another sensor triggers a deployable restraint as taught in the current assignee's U.S. patent application Ser. No. 10/638,743 filed Aug. 11, 2003 and related patents and pending applications. In the teachings of this invention, two or more sensors, frequently accelerometers, are monitored simultaneously and the outputs of these multiple sensors can be combined continuously in making the crash severity analysis. U.S. Pat. No. 5,754,965 (Hagenbuch) describes an apparatus for diagnosing the state of health of a construction vehicle and providing the operator of the vehicle with a substantially real-time indication of the efficiency of the vehicle in performing as assigned task with respect to a predetermined goal. A processor in the vehicle monitors sensors that provide information regarding the state of health of the vehicle and the amount of work the vehicle has done. The processor records information that describes events leading up to the occurrence of an anomaly for later analysis. The sensors are also used to prompt the operator to operate the vehicle at optimum efficiency. The system of this patent does not predict or warn the operator or the home base of a pending problem. Asami et al. (U.S. Pat. No. 4,817,418) is directed to a failure diagnosis system for a vehicle including a failure display means for displaying failure information to a driver. This system only reports failures after they have occurred and does not predict them. Tieman et al. (U.S. Pat. No. 5,313,407) is directed, inter alia, to a system for providing an exhaust active noise control system, i.e., an electronic muffler system, including an input microphone 60 which senses exhaust noise at a first location 61 in an exhaust duct 58 . An engine has exhaust manifolds 56 , 57 feeding exhaust air to the exhaust duct 58 . The exhaust noise sensed by the microphone 60 is processed to obtain an output from an output speaker 65 arranged downstream of the input microphone 61 in the exhaust path in order to cancel the noise in the exhaust duct 58 . No attempt is made to diagnose system faults nor predict them. Haramaty et al. (U.S. Pat. No. 5,406,502) describes a system that monitors a machine in a factory and notifies maintenance personnel remote from the machine (not the machine operator) that maintenance should be scheduled at a time when the machine is not in use. Haramaty et al. does not expressly relate to vehicular applications. NASA Technical Support Package MFS-26529 “Engine Monitoring Based on Normalized Vibration Spectra”, describes a technique for diagnosing engine health using a neural network based system but does not suggest that this system can or should be used on land vehicles. A paper “Using acoustic emission signals for monitoring of production processes” by H. K. Tonshoff et al. also provides a good description of how acoustic signals can be used to predict the state of machine tools and is incorporated by reference herein in its entirety. Again no suggestion is made that this can be used for diagnosing components of land vehicles. 1.2 Pattern Recognition Marko et al. (U.S. Pat. No. 5,041,976) is directed to a diagnostic system using pattern recognition for electronic automotive control systems and particularly for diagnosing faults in the engine of a motor vehicle after they have occurred. For example, Marko et al. is interested in determining cylinder specific faults after the cylinder is operating abnormally. More specifically, Marko et al. is directed to detecting a fault in a vehicular electromechanical system directly, i.e., by means of the measurement of parameters of sensors which are designed to be affected only by that system, and after that fault has already manifested itself in the system. In order to form the fault detecting system, the parameters from these sensors are input to a pattern recognition system for training thereof. Then, known faults are introduced and the parameters from the sensors are input into the pattern recognition system with an indicia of the known fault. Thus, during subsequent operation, the pattern recognition system can determine the fault of the electromechanical system based on the parameters of the sensors, assuming that the fault was “trained” into the pattern recognition system and has already occurred. When the electromechanical system is an engine, the parameters input into the pattern recognition system for training thereof, and used for fault detection during operation, all relate to the engine. In other words, each parameter will be affected by the operation of the engine and depend thereon and changes in the operation of the engine will alter the parameter, e.g., the manifold absolute pressure is an indication of the airflow into the engine. In this case, the signal from the manifold absolute pressure sensor may be indicative of a fault in the intake of air into the engine, e.g., the engine is drawing in too much or too little air, and is thus affected by the operation of the engine. Similarly, the mass air flow is the airflow into the engine and is an alternative to the manifold absolute pressure. It is thus a parameter that is directly associated with, related to and dependent on the engine. The exhaust gas oxygen sensor is also affected by the operation of the engine, and thus directly associated therewith, since during normal operation, the mixture of the exhaust gas is neither rich or lean whereas during abnormal engine operation, the sensor will detect an abrupt change indicative of the mixture being too rich or too lean. Thus, the system of Marko et al. is based on the measurement of sensors which affect or are affected by, i.e., are directly associated with, the operation of the electromechanical system for which faults are to be detected. However, the system of Marko et al. does not detect faults in the sensors that are conducting the measurements, e.g., a fault in the exhaust gas oxygen sensor, or faults that are only developing but have not yet manifested themselves or faults in other systems. Rather, the sensors are used to detect a fault in the system after it has occurred. Marko does not attempt to forecast or predict that a fault will occur. Aside from the references above of assignee's patents and patent applications and the one example of an engine control system, pattern recognition has not been applied to the diagnosis of any faults on a vehicle. In the referenced examples, the engine controller for example, only sensors directly associated with the component have been used. No attempt has been made to forecast that a failure will occur and no system has been disclosed other than by the assignee for transmitting such diagnostic information to a site off of the vehicle. 2.0 Telematics Every automobile driver fears that his or her vehicle will break down at some unfortunate time, e.g., when he or she is traveling at night, during rush hour, or on a long trip away from home. To help alleviate that fear, certain luxury automobile manufacturers provide roadside service in the event of a breakdown. Nevertheless, unless the vehicle is equipped with OnStar® or an equivalent service, the vehicle driver must still be able to get to a telephone to call for service. It is also a fact that many people purchase a new automobile out of fear of a breakdown with their current vehicle. The inventions described herein are primarily concerned with preventing breakdowns and with minimizing maintenance costs by predicting component failure that would lead to such a breakdown before it occurs. Another important aspect disclosed in the Breed et al. patents relates to the operation of the cellular communications system in conjunction with the vehicle interior monitoring system. Vehicles can be provided with a standard cellular phone as well as the Global Positioning System (GPS), an automobile navigation or location system with an optional connection to a manned assistance facility. In the event of an accident, the phone may automatically call 911 for emergency assistance and report the exact position of the vehicle. If the vehicle also has a system as described below for monitoring each seat location, the number and perhaps the condition of the occupants could also be reported. In that way, the emergency service (EMS) would know what equipment and how many ambulances to send to the accident site. Moreover, a communication channel can be opened between the vehicle and a monitoring facility/emergency response facility or personnel to determine how badly people are injured, the number of occupants in the vehicle, and to enable directions to be provided to the occupant(s) of the vehicle to assist in any necessary first aid prior to arrival of the emergency assistance personnel. Communications between a vehicle and a remote assistance facility are also important for the purpose of diagnosing problems with the vehicle and forecasting problems with the vehicle, called prognostics. Motor vehicles contain complex mechanical systems that are monitored and regulated by computer systems such as electronic control units (ECUs) and the like. Such ECUs monitor various components of the vehicle including engine performance, carburetion, speed/acceleration control, transmission, exhaust gas recirculation (EGR), braking systems, etc. However, vehicles perform such monitoring typically only for the vehicle driver and without communication of any impending results, problems and/or vehicle malfunction to a remote site for trouble-shooting, diagnosis or tracking for data mining. In the past, systems that provide for remote monitoring did not provide for automated analysis and communication of problems or potential problems and recommendations to the driver. As a result, the vehicle driver or user is often left stranded, or irreparable damage occurs to the vehicle as a result of neglect or driving the vehicle without the user knowing the vehicle is malfunctioning until it is too late, such as low oil level and a malfunctioning warning light, fan belt about to fail, failing radiator hose etc. U.S. Pat. No. 5,400,018 (Scholl et al.) describes a system for relaying raw sensor output from an off road work site relating to the status of a vehicle to a remote location over a communications data link. The information consists of fault codes generated by sensors and electronic control modules indicating that a failure has occurred rather than forecasting a failure. The vehicle does not include a system for performing diagnosis. Rather, the raw sensor data is processed at an off-vehicle location in order to arrive at a diagnosis of the vehicle's operating condition. Bi-directional communications are described in that a request for additional information can be sent to the vehicle from the remote location with the vehicle responding and providing the requested information but no such communication takes place with the vehicle operator and not of an operator of a vehicle traveling on a road. Also, Scholl et al. does not teach the diagnostics of the problem or potential problem on the vehicle itself nor does it teach the automatic diagnostics or any prognostics. In Scholl et al. the determination of the problem occurs at the remote site by human technicians. U.S. Pat. No. 5,955,942 (Slilkin et al.) describes a method for monitoring events in vehicles in which electrical outputs representative of events in the vehicle are produced, the characteristics of one event are compared with the characteristics of other events accumulated over a given period of time and departures or variations of a given extent from the other characteristics are determined as an indication of a significant event. A warning is sent in response to the indication, including the position of the vehicle as determined by a global positioning system on the vehicle. For example, for use with a railroad car, a microprocessor responds to outputs of an accelerometer by comparing acceleration characteristics of one impact with accumulated acceleration characteristics of other impacts and determines departures of a given magnitude from the other characteristics as a failure indication which gives rise of a warning. Of course there are many areas of the country where cell phone reception is not available and thus a system that relies on the availability of such a system for diagnostics will not always be available and thus has a significant failure mode. Furthermore, it would be difficult if not impossible for such a location to have all of the information to diagnose problems with all vehicle models that are on the road and to be able to retrieve that information and act on raw data on a continuous basis to keep track of whether all vehicles on the roadways are operating properly and to forecast all potential problems with each vehicle. Thus, this function must be resident on the vehicle. Additionally is a human operator is required then the system quickly becomes unmanageable. 3.0 Definitions As used herein, a diagnosis of the “state of the vehicle” means a diagnosis of the condition of the vehicle with respect to its stability and proper running and operating condition. Thus, the state of the vehicle could be normal when the vehicle is operating properly on a highway or abnormal when, for example, the vehicle is experiencing excessive angular inclination (e.g., two wheels are off the ground and the vehicle is about to rollover), the vehicle is experiencing a crash, the vehicle is skidding, and other similar situations. A diagnosis of the state of the vehicle could also be an indication that one of the parts of the vehicle, e.g., a component, system or subsystem, is operating abnormally. As used herein, a “part” of the vehicle includes any component, sensor, system or subsystem of the vehicle such as the steering system, braking system, throttle system, navigation system, airbag system, seatbelt retractor, air bag inflation valve, air bag inflation controller and airbag vent valve, as well as those listed below in the definitions of “component” and “sensor”. As used herein, a “sensor system” includes any of the sensors listed below in the definition of “sensor” as well as any type of component or assembly of components which detect, sense or measure something. The term “vehicle” shall mean any means for transporting or carrying something including automobiles, trucks, vans, containers, trailers, boats, railroad cars and engines. The term “gage” as used herein interchangeably with the terms “gauge”, “sensor” and “sensing device”. The following additional terms will be used in the description of the invention and for the sake of clarity are defined here. The “A-pillar” of a vehicle and specifically of an automobile is defined as the first roof supporting pillar from the front of the vehicle and usually supports the front door. It is also known as the hinge pillar. The “B-Pillar” is the next roof support pillar rearward from the A-Pillar. The “C-Pillar” is the final roof support usually at or behind the rear seats. The windshield header as used herein includes the space above the front windshield including the first few inches of the roof. The headliner is the roof interior cover that extends back from the header. The term “squib” represents the entire class of electrically initiated pyrotechnic devices capable of releasing sufficient energy to cause a vehicle window to break, for example. It is also used to represent the mechanism which starts the burning of an initiator which in turn ignites the propellant within an inflator. The term “airbag module” generally connotes a unit having at least one airbag, gas generator means for producing a gas, attachment or coupling means for attaching the airbag(s) to and in fluid communication with the gas generator means so that gas is directed from the gas generator means into the airbag(s) to inflate the same, initiation means for initiating the gas generator means in response to a crash of the vehicle for which deployment of the airbag is desired and means for attaching or connecting the unit to the vehicle in a position in which the deploying airbag(s) will be effective in the passenger compartment of the vehicle. In the instant invention, the airbag module may also include occupant sensing components, diagnostic and power supply electronics and componentry which are either within or proximate to the module housing. The term “occupant protection device” or “occupant restraint device” as used herein generally includes any type of device which is deployable in the event of a crash involving the vehicle for the purpose of protecting an occupant from the effects of the crash and/or minimizing the potential injury to the occupant. Occupant restraint or protection devices thus include frontal airbags, side airbags, seatbelt tensioners, knee bolsters, side curtain airbags, externally deployable airbags and the like. “Pattern recognition” as used herein will generally mean any system which processes a signal that is generated by an object (e.g., representative of a pattern of returned or received impulses, waves or other physical property specific to and/or characteristic of and/or representative of that object) or is modified by interacting with an object, in order to determine to which one of a set of classes that the object belongs. Such a system might determine only that the object is or is not a member of one specified class, or it might attempt to assign the object to one of a larger set of specified classes, or find that it is not a member of any of the classes in the set. The signals processed are generally a series of electrical signals coming from transducers that are sensitive to acoustic (ultrasonic) or electromagnetic radiation (e.g., visible light, infrared radiation, capacitance or electric and/or magnetic fields), although other sources of information are frequently included. Pattern recognition systems generally involve the creation of a set of rules that permit the pattern to be recognized. These rules can be created by fuzzy logic systems, statistical correlations, or through sensor fusion methodologies as well as by trained pattern recognition systems such as neural networks, combination neural networks, cellular neural networks or support vector machines. A trainable or a trained pattern recognition system as used herein generally means a pattern recognition system that is taught to recognize various patterns constituted within the signals by subjecting the system to a variety of examples. The most successful such system is the neural network used either singly or as a combination of neural networks. Thus, to generate the pattern recognition algorithm, test data is first obtained which constitutes a plurality of sets of returned waves, or wave patterns, or other information radiated or obtained from an object (or from the space in which the object will be situated in the passenger compartment, i.e., the space above the seat) and an indication of the identify of that object. A number of different objects are tested to obtain the unique patterns from each object. As such, the algorithm is generated, and stored in a computer processor, and which can later be applied to provide the identity of an object based on the wave pattern being received during use by a receiver connected to the processor and other information. For the purposes here, the identity of an object sometimes applies to not only the object itself but also to its location and/or orientation in the passenger compartment. For example, a rear facing child seat is a different object than a forward facing child seat and an out-of-position adult can be a different object than a normally seated adult. Not all pattern recognition systems are trained systems and not all trained systems are neural networks. Other pattern recognition systems are based on fuzzy logic, sensor fusion, Kalman filters, correlation as well as linear and non-linear regression. Still other pattern recognition systems are hybrids of more than one system such as neural-fuzzy systems. The use of pattern recognition, or more particularly how it is used, is important to the instant invention. In the above-cited prior art, except in that assigned to the current assignee, pattern recognition which is based on training, as exemplified through the use of neural networks, is not mentioned for use in monitoring the interior passenger compartment or exterior environments of the vehicle in all of the aspects of the invention disclosed herein. Thus, the methods used to adapt such systems to a vehicle are also not mentioned. A pattern recognition algorithm will thus generally mean an algorithm applying or obtained using any type of pattern recognition system, e.g., a neural network, sensor fusion, fuzzy logic, etc. To “identify” as used herein will generally mean to determine that the object belongs to a particular set or class. The class may be one containing, for example, all rear facing child seats, one containing all human occupants, or all human occupants not sitting in a rear facing child seat, or all humans in a certain height or weight range depending on the purpose of the system. In the case where a particular person is to be recognized, the set or class will contain only a single element, i.e., the person to be recognized. A “combination neural network” as used herein will generally apply to any combination of two or more neural networks that are either connected together or that analyze all or a portion of the input data. A combination neural network can be used to divide up tasks in solving a particular occupant problem. For example, one neural network can be used to identify an object occupying a passenger compartment of an automobile and a second neural network can be used to determine the position of the object or its location with respect to the airbag, for example, within the passenger compartment. In another case, one neural network can be used merely to determine whether the data is similar to data upon which a main neural network has been trained or whether there is something radically different about this data and therefore that the data should not be analyzed. Combination neural networks can sometimes be implemented as cellular neural networks. Preferred embodiments of the invention are described below and unless specifically noted, it is the applicants' intention that the words and phrases in the specification and claims be given the ordinary and accustomed meaning to those of ordinary skill in the applicable art(s). If the applicant intends any other meaning, he will specifically state he is applying a special meaning to a word or phrase. Likewise, applicants' use of the word “function” here is not intended to indicate that the applicants seek to invoke the special provisions of 35 U.S.C. §112, sixth paragraph, to define their invention. To the contrary, if applicants wish to invoke the provisions of 35 U.S.C. §112, sixth paragraph, to define their invention, they will specifically set forth in the claims the phrases “means for” or “step for” and a function, without also reciting in that phrase any structure, material or act in support of the function. Moreover, even if applicants invoke the provisions of 35 U.S.C. §112, sixth paragraph, to define their invention, it is the applicants' intention that their inventions not be limited to the specific structure, material or acts that are described in the preferred embodiments herein. Rather, if applicants claim their inventions by specifically invoking the provisions of 35 U.S.C. §112, sixth paragraph, it is nonetheless their intention to cover and include any and all structure, materials or acts that perform the claimed function, along with any and all known or later developed equivalent structures, materials or acts for performing the claimed function. | <SOH> OBJECTS AND SUMMARY OF THE INVENTION <EOH>1.0 Telematics Objects of the inventions disclosed herein include: 1. To provide new and improved weight or load measuring sensors, switches, temperature sensors, acceleration sensors, angular position sensors, angular rate sensors, angular acceleration sensors, proximity sensors, rollover sensors, occupant presence and position sensors, strain sensors and humidity sensors which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 2. To provide new and improved sensors for detecting the presence of fluids or gases which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 3. To provide new and improved sensors for detecting chemicals which utilize wireless data transmission, wireless power transmission, and/or surface acoustic wave technology with the data obtained by the sensors being transmittable via a telematics link to a remote location. 4. To utilize any of the foregoing sensors for a vehicular component control system in which a component, system or subsystem in the vehicle is controlled based on the information provided by the sensor. Additionally, the information provided by the sensor can be transmitted via a telematics link to one or more remote facilities for further analysis. 5. To provide a new and improved method and system for diagnosing components in a vehicle and the operating status of the vehicle and alerting the vehicle's dealer, or another repair facility, via a telematics link that a component of the vehicle is functioning abnormally and may be in danger of failing. 6. To provide a new and improved method and apparatus for obtaining information about a vehicle system and components in the vehicle in conjunction with failure of the component or the vehicle and sending this information to the vehicle manufacturer. 7. To provide a new and improved method and system for diagnosing components in a vehicle by monitoring the patterns of signals emitted from the vehicle components and, through the use of pattern recognition technology, forecasting component failures before they occur. Vehicle component behavior is thus monitored over time in contrast to systems that wait until a serious condition occurs. The forecast of component failure can be transmitted to a remote location via a telematics link. 8. To provide a new and improved on-board vehicle diagnostic module utilizing pattern recognition technologies which are trained to differentiate normal from abnormal component behavior. The diagnosis of component behavior can be transmitted to a remote location via a telematics link. 9. To provide a diagnostic module that determines whether a component is operating normally or abnormally based on a time series of data from a single sensor or from multiple sensors that contain a pattern indicative of the operating status of the component. The diagnosis of component operation can be transmitted to a remote location via a telematics link. 10. To provide a diagnostic module that determines whether a component is operating normally or abnormally based on data from one or more sensors that are not directly associated with the component, i.e., do not depend on the operation of the component. The diagnosis of component operation can be transmitted to a remote location via a telematics link. 11. To incorporate surface acoustic wave technology into sensors on a vehicle with the data obtained by the sensors being transmittable via a telematics link to a remote location. 12. To provide new and improved sensors which obtain and provide information about the vehicle, about individual components, systems, vehicle occupants, subsystems, or about the roadway, ambient atmosphere, travel conditions and external objects with the data obtained by the sensors being transmittable via a telematics link to a remote location. 13. To alert the dealer, or other repair facility, that a component of the vehicle is functioning differently than normal and is in danger of failing. 14. To provide a device which provides information to the vehicle manufacturer of the events leading to a component failure. 15. To provide new and improved sensors for a vehicle which wirelessly transmits information about a state measured or detected by the sensor. In order to achieve these objects and others, an information management and monitoring system for a vehicle in accordance with the invention includes a vehicle monitoring system including a plurality of sensors for monitoring components of the vehicle, a diagnostic module arranged on the vehicle and coupled to the vehicle monitoring system to receive and process data about the monitored components therefrom, and a remote service center capable of servicing the vehicle components. A communication system, e.g., a cellular telephone capable of voice communications, is arranged on the vehicle and coupled to the diagnostic module to enable communications of data from the diagnostic module to the remote service center, for example using a satellite or relay link, such that the remote service center receives data about the monitored components of the vehicle. The remote service center can be situated at a dealer which can then have its personnel contact the driver or another occupant of the vehicle, e.g., via the telephone, to schedule service of the vehicle, the service being determined based on the communicated data from the diagnostic module on the vehicle. The diagnostic module may derive diagnostic data from data about the monitored components provided by the sensors of the vehicle monitoring system, e.g., an indication of a potential failure of one of the components of the vehicle. A user interactive device, such as a display, may be coupled to and controlled by the diagnostic module such that a message about the component failure may be provided to the driver or other vehicle occupant. A vehicle bus may be provided to couple the diagnostic module, vehicle monitoring system and communication system. A method for information management and monitoring of a vehicle includes arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle, arranging a diagnostic module on the vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on the vehicle to the diagnostic module, and establishing communications between the diagnostic module and a remote service center capable of servicing the monitored components to enable transmission of data between the diagnostic module and the remote service center. As such, the remote service center receives data about the monitored components of the vehicle and can direct personnel to contact the driver or other occupant of the vehicle to schedule servicing thereof, with the service being required being based on the communicated data. The same variations to the system described above can be applied in this method as well. A method for scheduling servicing of a vehicle in accordance with the invention includes arranging a vehicle monitoring system including a plurality of sensors on the vehicle to monitor components of the vehicle, arranging a diagnostic module on the vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on the vehicle to the diagnostic module, establishing communications between the diagnostic module and a dealer capable of servicing the monitored components to enable transmission of data between the diagnostic module and the dealer such that the dealer receives data about the monitored components of the vehicle, and upon receiving data from the diagnostic module at the dealer, contacting the vehicle owner to schedule repair or maintenance of the vehicle. The same variations to the system described above can be applied in this method as well. A method for information management and monitoring of a plurality of vehicles in accordance with the invention is designed for manufacturers and other parties interested in statistical failure of vehicle components and includes arranging a vehicle monitoring system including a plurality of sensors on each vehicle to monitor components of the vehicle, arranging a diagnostic module on each vehicle, directing data about the monitored components from the vehicle monitoring system to the diagnostic module for analysis and processing thereby, coupling a communication system on each vehicle to the diagnostic module, establishing communications between the diagnostic module and a data gathering facility which accumulates information about the failure rate of the components to enable transmission of data between the diagnostic module and the data gathering facility such that the data gathering facility receives data about the monitored components of the vehicle, and accumulating date from the vehicle at the data gathering facility to enable calculation of statistics about failure rate of the components. Diagnostic data may be derived in the diagnostic module from the data about the monitored components provided by the vehicle monitoring system, e.g., using a pattern recognition algorithm, and the derived data transmitted to the data gathering facility. The derived data may be an indication of a potential or actual failure of one of the components of the vehicle. 2. Diagnostics 2.1 General Diagnostics Further objects of inventions disclosed herein are: 1. To prevent vehicle breakdowns. 2. To alert the driver of the vehicle that a component of the vehicle is functioning differently than normal and might be in danger of failing. 3. To provide an early warning of a potential component failure and to thereby minimize the cost of repairing or replacing the component. 4. To provide a device which will capture available information from signals emanating from vehicle components for a variety of uses such as current and future vehicle diagnostic purposes. 5. To provide a device that uses information from existing sensors for new purposes thereby increasing the value of existing sensors and, in some cases, eliminating the need for sensors that provide redundant information. 6. To provide a device which analyzes vibrations from various vehicle components that are transmitted through the vehicle structure and sensed by existing vibration sensors such as vehicular crash sensors used with airbag systems or by special vibration sensors, accelerometers, or gyroscopes. 2.2 Pattern Recognition Further objects of inventions disclosed herein are: 1. To provide a device which is trained to recognize deterioration in the performance of a vehicle component, or of the entire vehicle, based on information in signals emanating from the component or from vehicle angular and linear accelerations. 2. To apply pattern recognition techniques based on training to diagnosing potential vehicle component failures. 3. To apply trained pattern recognition techniques using multiple sensors to provide an early prediction of the existence and severity of an accident. 2.3 Vehicle or Component Control Further objects of inventions disclosed herein are: 1. To utilize pattern recognition techniques and the output from multiple sensors to determine at an early stage that a vehicle rollover might occur and to take corrective action through control of the vehicle acceleration, brakes and steering to prevent the rollover or if it is preventable, to deploy side head protection airbags to reduce the injuries. 2. To apply component diagnostic techniques in combination with intelligent or smart highways wherein vehicles may be automatically guided without manual control in order to permit the orderly exiting of the vehicle from a restricted roadway prior to a breakdown of the vehicle. 3. To use the output from multiple sensors to determine that the vehicle is skidding or sliding and to send messages to the various vehicle control systems to activate the throttle, brakes and/or steering to correct for the vehicle sliding or skidding motion. | 20050119 | 20060725 | 20050609 | 67987.0 | 11 | BEAULIEU, YONEL | VEHICULAR INFORMATION AND MONITORING SYSTEM AND METHODS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,039,200 | ACCEPTED | Dynamic channel selection for RF telemetry with implantable device | A telemetry system for radio-frequency communications between an implantable medical device and an external device providing improved noise immunity is disclosed. Multiple communications channels are used to enable establishment and re-establishment of communications between a particular pair of devices in a multiple device environment. | 1. A telemetry system for enabling radio-frequency (RF) communications between an implantable medical device and an external device over a wireless medium, comprising: an antenna, an RF transmitter, an RF receiver, and a controller incorporated into each of the implantable and external devices, wherein the RF transmitter and receiver of each device are tunable and may be switched among a plurality of different communications channels which differ in frequency; wherein the controller is interfaced to the RF transmitter and receiver in each device to enable establishment of a communications session and data transfer over a selected channel; wherein the external device and implantable device controllers are programmed to switch from a first communications channel to a second communications channel upon a degradation in the quality of the first communications channel. 2. The system of claim 1 wherein the external device controller is programmed to monitor the quality of a communications channel by determining if the channel throughput over a certain time falls below a certain level. 3. The system of claim 1 wherein the external device controller is programmed to monitor the quality of a communications channel by determining if a specified number of data frames are unacknowledged. 4. The system of claim 1 wherein the external device controller is programmed to monitor the quality of a communications channel by determining if the frame error rate exceeds a threshold value. 5. The system of claim 1 wherein the implantable device and external device controllers are programmed to revert to a selected channel if a communications session is interrupted. 6. The system of claim 1 wherein the external device and implantable device controllers are programmed to use a designated control channel for initiating a communications session and to use a designated data channel for transferring data. 7. The system of claim 6 wherein the external device controller is programmed to search for an available data channel by checking the data channels for activity. 8. The system of claim 7 wherein the external device controller is programmed to tune its receiver to a particular data channel, listen for a valid preamble known to be transmitted by all devices during the transmission of data frames, and regard the data channel as unused if no such preambles are detected over a specified time period. 9. The system of claim 7 wherein the external device controller is programmed to tune its receiver to a particular data channel, measure the signal strength of the channel over a specified period of time, and regard the channel as unused if the peak signal strength over specified period of time is less than a specified value. 10. The system of claim 7 wherein the external device controller is programmed to: tune its receiver to a particular data channel; listen for a valid preamble known to be transmitted by all devices during the transmission of data frames; measure the signal strength of the channel over a specified period of time; and, regard the data channel as unused if no such preambles are detected over a specified time period and if the peak signal strength over specified period of time is less than a specified value. 11. A method by which an implantable medical device and an external device may communicate over a wireless medium, comprising: providing a plurality of different communications channels which differ in frequency; establishing a communications session and data transfer between the implantable medical device and the external device over a selected channel; and, switching from a first communications channel to a second communications channel upon a degradation in the quality of the first communications channel. 12. The method of claim 11 further comprising monitoring the quality of a communications channel by determining if the channel throughput over a certain time falls below a certain level. 13. The method of claim 11 further comprising monitoring the quality of a communications channel by determining if a specified number of data frames are unacknowledged. 14. The method of claim 11 further comprising monitoring the quality of a communications channel by determining if the frame error rate exceeds a threshold value. 15. The method of claim 11 further comprising reverting to a selected channel if a communications session is interrupted. 16. The method of claim 11 further comprising using a designated control channel for initiating a communications session and to use a designated data channel for transferring data. 17. The method of claim 16 further comprising searching for an available data channel by checking the data channels for activity. 18. The method of claim 17 further comprising listening to a particular data channel for a valid preamble known to be transmitted by all devices during the transmission of data frames and regarding the data channel as unused if no such preambles are detected over a specified time period. 19. The method of claim 17 further comprising measuring the signal strength of a particular data channel over a specified period of time and regarding the channel as unused if the peak signal strength over specified period of time is less than a specified value. 20. The method of claim 17 further comprising: listening to a particular data channel for a valid preamble known to be transmitted by all devices during the transmission of data frames; measuring the signal strength of the particular data channel over a specified period of time; and, regarding the data channel as unused if no such preambles are detected over a specified time period and if the peak signal strength over specified period of time is less than a specified value. | FIELD OF THE INVENTION This invention pertains to implantable medical devices such as cardiac pacemakers and implantable cardioverter/defibrillators. In particular, the invention relates to a system and method for implementing telemetry in such devices. BACKGROUND Implantable medical devices (IMDs), including cardiac rhythm management devices such as pacemakers and implantable cardioverter/defibrillators, typically have the capability to communicate data with an external device (ED) via a radio-frequency telemetry link. One such external device is an external programmer used to program the operating parameters of an implanted medical device. For example, the pacing mode and other operating characteristics of a pacemaker are typically modified after implantation in this manner. Modern implantable devices also include the capability for bidirectional communication so that information can be transmitted to the programmer from the implanted device. Among the data that may typically be telemetered from an implantable device are various operating parameters and physiological data, the latter either collected in real-time or stored from previous monitoring operations. External programmers are commonly configured to communicate with an IMD over an inductive link. Coil antennas in the external programmer and the IMD are inductively coupled so that data can be transmitted by modulating a carrier waveform which corresponds to the resonant frequency of the two coupled coils. An inductive link is a short-range communications channel requiring that the coil antenna of the external device be in close proximity to the IMD, typically within a few inches. Other types of telemetry systems may utilize far-field radio-frequency (RF) electromagnetic radiation to enable communications between an IMD and an ED over a wireless medium. Such long-range RF telemetry allows the IMD to communicate with an ED, such as an external programmer or remote monitor, without the need for close proximity. In either the home or the clinic, however, there are external sources of RF energy which may interfere with communication between the ED and IMD. It is also common in clinical settings for there to be multiple implantable and/or external devices are present in an area so that communication over the wireless medium is possible between the multiple devices. Access to the medium among the multiple devices must be controlled in this situation in order for a communications session between any pair of devices to be established. It would also be desirable for there to be the possibility of multiple communications sessions between different devices occurring concurrently. SUMMARY The present disclosure relates to an RF telemetry system and method for enabling communication between an implantable medical device and an external device with an improved tolerance to noise from external sources. Multiple communications channels at different frequencies are provided which may be dynamically switched between during a communications session. In one embodiment, both devices are programmed to switch to different channels according to a predetermined scheme during the communications session. In another embodiment, the devices switch to a different channel when the quality of the presently used channel has degraded to an unacceptable level. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a telemetry system for an implantable device and an external device. FIG. 2 illustrates an exemplary embodiment of a scheme for dynamic channel selection. FIG. 3 illustrates an exemplary embodiment of a scheme for dynamic channel selection which employs separate data and control channels. DETAILED DESCRIPTION Described below is a system and method for providing wireless RF telemetry between an implantable medical device and an external device with improved tolerance to external noise. Most noise from external sources is of the narrow-band type, where the energy of the noise is confined to a particular frequency range. Examples of narrow-band noise sources include communications devices such as wireless telephones as well as many other kinds of electronic equipment which are commonly found in the home and in the clinic. When such narrow-band noise is in the same frequency range used for telemetry, it is said to be in-band and can interfere with communications between the devices. In order to deal with the problem of in-band noise, the available bandwidth of the wireless medium is divided into multiple communications channels at different frequencies. At any given time, only the channels at the same frequency as the in-band noise are interfered with. In one embodiment, the external device and implantable device are programmed to switch from channel to channel at predetermined times according to a switching algorithm during a communications session in order to minimize the effects of noise in one of the channels. In another embodiment, after a communications session is established and data transfer is taking place on one of the channels, the external device is programmed to monitor the quality of the channel so that a switch to another channel can be made if the channel currently being used has become degraded due to external noise. Channel quality may be monitored, for example, by monitoring particular quality parameter, such as the data transfer rate or throughput, during a communications session and comparing it to a threshold value. Alternative quality parameters such as the error rate, the number of repeated frames during a communications session, or the length of time in which no data transfer has taken place could also be compared to threshold values. If one or more quality parameters indicate that the channel quality has degraded to an unacceptable level and is thus effectively disabled, the external device may then be programmed to find an available unused channel with an acceptable noise level and switch the communications session with the implantable device to new channel. The channel switching may be accomplished by the external device communicating the new channel information to the implantable device, either over the presently used but degraded channel or over a predetermined alternate channel, and both devices then switching to the new channel. In the case where an alternate channel is to be used to communicate the new channel information, both the external and implantable device may be programmed to revert to a designated alternate channel if no communications are received over the currently used channel for a specified period of time. Multiple alternate channels may be provided for this purpose to allow for the possibility that an alternate channel may also be so degraded by noise that no communications are possible, with alternate channels being used in a defined sequence. It is also possible for an alternate channel which is reverted to by both devices to be used as the new channel for continuing the communications process. The channel switching process as just described may be repeated as necessary during the communications session. The multiple channels provided for noise reduction may also be used to allow concurrent communications between multiple devices over the common wireless medium. This is especially desirable in a clinical environment where there may be a number of external and implantable devices in range of one another. In one embodiment, a number of the channels are designated as data channels, each of which can be used for data transfer between an external and an implantable device, and one or more of the other channels are designated as control channels over which the devices communicate in order to establish a communications session by transmitting control frames. Once a communications session is established between two devices, one of the devices finds and selects an unused data channel and commands the other device over the control channel to utilize the selected data channel for further communications during which data transfer takes place. A control channel may also be used as a designated alternate channel so that both devices switch back to a specified control channel if the selected data channel becomes disabled. The data channel selection process is then repeated, and the devices switch to the selected data channel to continue the communications session. As described above, dynamic channel selection for providing improved noise immunity may be employed in a number of different wireless communications regimes. Various alternative embodiments are described in detail below after a description of exemplary hardware components. 1. Exemplary Hardware Platform FIG. 1 shows the primary telemetry components of an external device 200 and an implantable medical device 100. In this functional block diagram, the components are shown as being identical in each device. In this exemplary embodiment, the external device and the implantable device are microprocessor-based devices each having a controller 102a or 102b that includes a microprocessor and memory for data and program storage that supervises overall device operation as well as telemetry. Code executed by the controller also implements the dynamic channel selection schemes to be described below. The implantable device 100 may be a cardiac rhythm management device such as a pacemaker or implantable cardioverter/defibrillator, while the external device 200 may be an external programmer or a data-gathering device such as remote monitor. A user interface 300 (e.g., a keyboard and monitor) may be provided to enable a user such as a clinician to direct the operation of the external device. A long-range RF receiver 120a or 120b and a long-range RF transmitter 110a or 110b are interfaced to the microprocessor 102a or 102b in the implantable device and the external device, respectively. Also in each device, the transmitter and receiver are coupled to an antenna 101a or 101b through a transmit/receive switch 130a or 130b. The transmit/receive switches 130a and 130b are controlled by the microprocessor and either passes radio-frequency signals from the transmitter to the antenna or from the antenna to the receiver to establish an RF link. To effect communications between the devices over the RF link, a radio-frequency carrier signal modulated with digital data is transmitted wirelessly from one antenna to the other. A demodulator for extracting digital data from the carrier signal is incorporated into each receiver, and a modulator for modulating the carrier signal with digital data is incorporated into each transmitter. The interface to the controller for the RF transmitter and receiver in each device enables data transfer. The RF receiver and transmitter of each device are tunable and may be switched among a plurality of communications channels which differ in frequency. The implantable device also incorporates a means by which the controller can power up or power down the RF receiver and/or transmitter in order to manage duty cycles. A wakeup timer 180 for defining the RF duty cycle is also shown for the implantable device, and this timer can either be implemented in code executed by the controller or can be discrete components. FIG. 1 also shows an inductively coupled transmitter/receiver 140a or 140b and antenna 150a or 150b for the implantable and external devices by which communication may take place over an inductive link when the two devices are in close physical proximity to one another. 2. Exemplary Channel Selection Schemes In the embodiments described below, the controllers of the external and implantable devices are programmed to operate their respective telemetry hardware in a manner which utilizes multiple communications channels. The multiple channels are defined with different carrier frequencies so that communications over one channel does not disturb communications over any of the other channels. A dynamic channel selection scheme is then employed to avoid channels which are corrupted with external noise. Two example embodiments are described, each of which utilizes multiple data channels for transmitting data between an external device and an implantable device. In the first embodiment, the data channels are also used to transmit control information for initiating a communications session. In the second embodiment one or more channels are designated as control channels and dedicated to the transmission of control information. FIG. 2 illustrates the steps performed by the external device controller in communicating with an implantable device via a long-range RF telemetry link according to one embodiment. In this embodiment, multiple channels are provided with each channel capable of being used for both initiating communications sessions and transferring data. At step 201, the external device waits until a communications session with an implantable device is scheduled to occur by a programmed command or until a command is received via a user interface to initiate a communications session. After either type of command, the external device monitors a designated first channel for activity at step 202. The designated first channel is a particular one of the multiple channels which both devices have agreed to use first for establishing a communications session. The choice of a designated first channel may be communicated from the external device to the implantable device using the inductive link or during a previous communications session using long-range telemetry. The device continues to monitor the designated first channel until the channel is found to be not busy at step 203. Then, at step 204, a communications session is initiated, and data transfer begins at step 205. When the data transfer has been completed, as determined at step 206, the device returns to step 201. As the data is being transferred, the external device monitors the channel quality at step 207 and continues transferring data on the selected channel if no channel degradation is detected at step 208. If channel degradation is detected to the extent that the channel is non-operational, as determined at step 209, the external device and the implantable device both revert to a previously agreed upon fall-back channel at step 210 where the communications session is re-established by transmission of control frames. If the fall-back channel is not available, either because of interference or because it is busy, a plurality of previously agreed upon fall-back channels may be reverted to in a specified sequence. A timeout duration may be specified for each fall-back channel so that if no communications are established within the timeout duration, the devices move to the next fall-back channel in the sequence. Data transfer then continues at step 205 either on the fall-back channel or on a channel selected by the external device and communicated to the implantable device via the fall-back channel. If, at step 209, it is determined that the channel is degraded to an unacceptable level but is still operational, the external device ceases transferring data and begins scanning to find another non-busy channel at step 211. Such scanning may be performed over all of the multiple channels or over a specified and agreed upon sub-group or pool of channels. After selection of another channel, the external device communicates the information to the implantable device over the presently used channel. Both devices then switch to the selected channel and continue to transfer data at step 205. In another embodiment, the multiple channels are divided into data channels and one or more control channels, the former used for data transfer and the latter used for transmitting control frames in order to initiate and maintain a communications session. When multiple devices are in range of one another and want to access the common wireless medium, the embodiment as described with reference to FIG. 2 may cause delays in initiating a communications session between a pair of devices if the designated first channel is presently being used for data transfer by another pair of devices. By dedicating a control channel to the transmission of control frames only, it becomes more likely that a pair of devices will be able to access the control channel without delay and initiate a communications session. FIG. 3 illustrates a dynamic channel selection scheme which utilizes a single control channel for use by multiple devices in initiating communications sessions. (Other embodiments may employ a plurality of such control channels.) At step 301, the external device waits for a scheduled or manually input command to initiate a communications session. After such a command, the control channel is monitored for activity at step 302 until it becomes available. When the control channel is not busy, as determined at step 303, a communications session is initiated with a selected implantable device via the transmission of control frames over the control channel at step 304. Also transmitted to the implantable device over the control channel as part of a control frame is the identification of a data channel selected by the external device for use in the subsequent data transfer. Both devices then switch to the selected data channel for further transfer of data. When the data transfer has been completed, as determined at step 306, the device returns to step 301. As the data is being transferred, the external device monitors the channel quality of the data channel at step 307 and continues transferring data on the selected data channel if no channel degradation is detected at step 308. If channel degradation is detected, either to the extent that the data channel is non-operational or merely unacceptable, the external device ceases transferring data and begins scanning to find another non-busy channel at step 309. The scanning may cover all data channels or a specified sub-group of the data channels. After selection of another data channel, the external device returns to step 302 to wait for access to the control channel. A communications session is then re-established with the implantable device at step 304, and an identification of the selected data channel is transmitted to the implantable device. Both devices then switch to the selected data channel and continue to transfer data at step 305. Various techniques may be used in implementing the functions performed by the embodiments described above. Examples of such techniques are described in the following paragraphs. Initiation of a communications session may involve a handshaking procedure in which control frames are transmitted to synchronize the subsequent activity of both devices. For example, when the external device wishes to transmit data, an RTS frame is transmitted to the implantable device which then responds with a CTS frame. Similarly, when the external device wishes to receive data, an RRTS frame is transmitted to the implantable device, the implantable device responds with an RTS frame, and the external device transmits a CTS frame. One or more of the control frames may also contain other information such as the device ID, amount of data to be transmitted, and an identification of which channel is to be used for data transfer. The device receiving a CTS frame then begins transmitting data frames. During the data transfer, data frames sent by one of the devices are acknowledged by the other device with an ACK frame and repeated if necessary in order to ensure reliable data transmission. At various points in the embodiments described above, the external device searches for an available data channel by checking the data channels for activity. One way the external device may do this is to tune its receiver to a particular data channel and listen for a valid preamble known to be transmitted by all devices during the transmission of data frames. If no such preambles are detected over a specified time period (e.g., 200 msec) in a particular data channel, the external device can assume that the data channel is not being used. Alternatively, the external device may tune to a particular data channel and measure its signal strength over a specified period of time. If the peak signal strength over some period of time (e.g., 200 msec) is less than some defined value (e.g., −75 dBm where −85 dBm is considered the noise floor), then the data channel can be assumed to be clear and available for use. In another alternative, preamble detection and signal strength measurement can be combined so that a data channel is assumed to be available for use only if no preambles are detected and the peak signal strength is below a certain value over some period of time. However the availability of channels is determined, if a data channel is determined to be busy, the external device can proceed to check the other data channels for activity either randomly or in a defined sequence. Once a communications session has been established and data transfer is taking place over a selected data channel, environmental noise or other factors may disrupt communications over the channel. Both the external and implantable devices may be programmed to monitor the data transfer in order to determine if the quality of the link has fallen below a specified level so as to constitute an interruption of the communications session. For example, a communications interruption may be declared if the channel throughput falls below a certain level over a certain time (e.g., below 50% of channel capacity for 1 second), if a specified number of data frames are unacknowledged, and/or if the frame error rate exceeds a threshold value. Upon declaration of an interrupted session, both devices may be programmed to revert back to either a selected data channel or a control channel. After a clear and available data channel is found, the communications session is re-initiated, and the devices switch to the new data channel for data transfer. Control channels are also subject to interference from environmental noise or may suffer from degradation due to other factors. To deal with this problem, multiple control channels may be provided. For example, two control channels may be utilized with one designated as the primary control channel and the other designated as the secondary control channel. In an example embodiment, the primary control channel is always used for both connect and reconnect communications unless it is unavailable due to excess noise or other factors, in which case the secondary control channel is used. Excess noise in a control channel may be determined, for example, if the average signal strength exceeds a threshold value over a specified period of time (greater than −75 dBm over at least a 500 msec period) with no valid preambles being detected. In another embodiment, two connect control channels and two reconnect control channels are provided. The implantable device in an interrupted session first listens on the reconnect channel which is most isolated from the data channel that failed (e.g., farthest away in frequency). After some period of time (e.g., 500 msec), the implantable device begins cycling between the two reconnect channels, listening for some period of time on one channel (e.g., 200 msec) before switching to the other channel. In a similar fashion, the external device in an interrupted session also moves to the reconnect channel which is most isolated from the failed data channel and begins transmitting control frames (i.e., RRTS or RTS). If no response is received from the implantable device after some period of time (e.g., 500 msec), the external device cycles between the two reconnect control channels, transmitting control frames for some period of time (e.g., 50 msec) on each channel before moving to the other channel. As described earlier with reference to FIG. 1, the implantable device may be equipped with a wake up timer for the telemetry components in order to conserve energy. An implantable device not engaged in an active communications session must wake up periodically in order to monitor transmissions on the control channel or designated first data channel and determine if an external device is attempting to communicate with it. In an embodiment utilizing primary and secondary control channels, the implantable device may wake up to check for a signal on both the primary and secondary control channels, alternate between the control channels during each wakeup, or check for a signal on the primary control channel more frequently than it wakes up to check for a signal on the secondary control channel. For example, an implantable device not in an active communications session may wake up every 10 seconds to check the primary channel and wake up every 1 minute to check the secondary channel. The external device may transmit control frames alternately over each control channel at shorter intervals (e.g., 50 msec). Although the invention has been described in conjunction with the foregoing specific embodiment, many alternatives, variations, and modifications will be apparent to those of ordinary skill in the art. Such alternatives, variations, and modifications are intended to fall within the scope of the following appended claims. | <SOH> BACKGROUND <EOH>Implantable medical devices (IMDs), including cardiac rhythm management devices such as pacemakers and implantable cardioverter/defibrillators, typically have the capability to communicate data with an external device (ED) via a radio-frequency telemetry link. One such external device is an external programmer used to program the operating parameters of an implanted medical device. For example, the pacing mode and other operating characteristics of a pacemaker are typically modified after implantation in this manner. Modern implantable devices also include the capability for bidirectional communication so that information can be transmitted to the programmer from the implanted device. Among the data that may typically be telemetered from an implantable device are various operating parameters and physiological data, the latter either collected in real-time or stored from previous monitoring operations. External programmers are commonly configured to communicate with an IMD over an inductive link. Coil antennas in the external programmer and the IMD are inductively coupled so that data can be transmitted by modulating a carrier waveform which corresponds to the resonant frequency of the two coupled coils. An inductive link is a short-range communications channel requiring that the coil antenna of the external device be in close proximity to the IMD, typically within a few inches. Other types of telemetry systems may utilize far-field radio-frequency (RF) electromagnetic radiation to enable communications between an IMD and an ED over a wireless medium. Such long-range RF telemetry allows the IMD to communicate with an ED, such as an external programmer or remote monitor, without the need for close proximity. In either the home or the clinic, however, there are external sources of RF energy which may interfere with communication between the ED and IMD. It is also common in clinical settings for there to be multiple implantable and/or external devices are present in an area so that communication over the wireless medium is possible between the multiple devices. Access to the medium among the multiple devices must be controlled in this situation in order for a communications session between any pair of devices to be established. It would also be desirable for there to be the possibility of multiple communications sessions between different devices occurring concurrently. | <SOH> SUMMARY <EOH>The present disclosure relates to an RF telemetry system and method for enabling communication between an implantable medical device and an external device with an improved tolerance to noise from external sources. Multiple communications channels at different frequencies are provided which may be dynamically switched between during a communications session. In one embodiment, both devices are programmed to switch to different channels according to a predetermined scheme during the communications session. In another embodiment, the devices switch to a different channel when the quality of the presently used channel has degraded to an unacceptable level. | 20050119 | 20070515 | 20060720 | 96817.0 | A61N108 | 0 | PATEL, NATASHA | DYNAMIC CHANNEL SELECTION FOR RF TELEMETRY WITH IMPLANTABLE DEVICE | UNDISCOUNTED | 0 | ACCEPTED | A61N | 2,005 |
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11,039,202 | ACCEPTED | Central vacuum system with secondary airflow path | A central vacuum system includes a motor-cooling airflow path that provides sufficient cooling for the motor and its drive components even though the cooling air is partially restricted by a downstream filter that captures airborne carbon dust emitted from the motor's commutator brushes. A divider system creates multiple chambers within the vacuum system's canister, and in some embodiments, air passageways in the canister and in the divider system direct the cooling air through the chambers in a flow pattern that avoids contaminating the drive components with carbon dust. | 1. A central vacuum system for reducing the pressure of air to less than that of an ambient atmosphere that contains contaminants, the system comprising: a canister for installation at a substantially fixed location; a divider system disposed within the canister to help define within the canister a suction chamber, a motor chamber, a plenum, and an electrical chamber; a motor extending into the motor chamber, wherein the motor heats the air therein; a main impeller coupled to the motor to help create a suction pressure within the suction chamber; a secondary impeller coupled to the motor, wherein the secondary impeller forces air from the ambient atmosphere into the electrical chamber, forces air from the electrical chamber into the plenum, forces air from the plenum into the motor chamber, and forces air from the motor chamber to the ambient atmosphere; and a motor drive component disposed within the electrical chamber and being electrically coupled to the motor, wherein the air forced through the electrical chamber helps cool the motor drive component. 2. The central vacuum system of claim 1, wherein the air in the electrical chamber is upstream of the air in the motor chamber. 3. The central vacuum system of claim 1, wherein the motor chamber conveys air at a greater flow rate than that of the electrical chamber. 4. The central vacuum system of claim 1, wherein the air in the plenum is cooler than the air in the electrical chamber. 5. The central vacuum system of claim 1, wherein the electrical chamber conveys air at an electrical chamber pressure, the plenum conveys air at a plenum pressure, the motor chamber conveys air at a motor chamber pressure, and the suction chamber conveys air at a suction pressure, wherein: i. the motor chamber pressure is greater than the ambient atmosphere pressure, ii. the ambient atmosphere pressure is greater than the electrical chamber pressure, iii. the electrical chamber pressure is greater than the plenum pressure, and iv. the plenum pressure is greater than the suction pressure. 6. The central vacuum system of claim 1, wherein the plenum is above the electrical chamber and the motor chamber, and the suction chamber is below the electrical chamber and the motor chamber. 7. The central vacuum system of claim 1, wherein the canister comprises a substantially cylindrical outer wall within which the electrical chamber is contained. 8. The central vacuum system of claim 7, wherein the weight of the electrical component is carried by the substantially cylindrical outer wall. 9. The central vacuum system of claim 1, wherein the divider system includes a first divider and a second divider, wherein the first divider separates the motor chamber from the suction chamber, and the second divider separates the plenum from the motor chamber, and the second divider defines an opening that places the plenum in fluid communication with the electrical chamber. 10. The central vacuum system of claim 9, wherein the divider system includes a third divider extending between the first divider and the second divider. 11. The central vacuum system of claim 1, further comprising: a main separator interposed between the main impeller and the suction chamber to help separate the contaminants from the air that the main impeller draws from the suction chamber; and a secondary filter interposed between the motor chamber and the ambient atmosphere, wherein the secondary filter helps filter the air passing from the motor chamber to the ambient atmosphere. 12. A central vacuum system for reducing the pressure of air to less than that of an ambient atmosphere that contains contaminants, the system comprising: a canister that includes a tubular sidewall and an upper end cap, wherein the upper end cap defines a plenum inlet, and the tubular sidewall defines a suction inlet, an electrical chamber inlet and a motor chamber outlet; a first divider disposed within the canister, wherein the first divider and the tubular sidewall help define a suction chamber that is in fluid communication with the ambient atmosphere via the suction inlet; a second divider disposed within the canister and defining an electrical chamber outlet, wherein the second divider, the tubular sidewall and the upper end cap help define a plenum that is in fluid communication with the ambient atmosphere via the plenum inlet; a third divider disposed within the canister and extending between the first divider and the second divider, wherein first divider, the second divider, the third divider and the sidewall help define a motor chamber and an electrical chamber, wherein the motor chamber is in fluid communication with the ambient atmosphere via the motor chamber outlet, the motor chamber is in fluid communication with the plenum, and the electrical chamber is in fluid communication with the ambient atmosphere via the electrical chamber inlet; a motor extending into the motor chamber, wherein the motor heats the air therein; a main impeller coupled to the motor to help create a suction pressure within the suction chamber; a motor drive component disposed within the electrical chamber and being electrically coupled to the motor, wherein the motor drive component heats the air within the electrical chamber; and a secondary impeller coupled to the motor, wherein the secondary impeller: i. forces air from the ambient atmosphere into the electrical chamber via the electrical chamber inlet, ii. forces air from the electrical chamber into the plenum via the electrical chamber outlet, iii. forces air from the ambient atmosphere into the plenum via the plenum inlet, iv. forces air from the plenum into the motor chamber, and v. forces air from the motor chamber to the ambient atmosphere via the motor chamber outlet. 13. The central vacuum system of claim 12, wherein the motor chamber conveys air at a greater flow rate than that of the electrical chamber. 14. The central vacuum system of claim 12, wherein the air in the plenum is cooler than the air in the electrical chamber. 15. The central vacuum system of claim 12, wherein the electrical chamber conveys air at an electrical chamber pressure, the plenum conveys air at a plenum pressure, the motor chamber conveys air at a motor chamber pressure, and the suction chamber conveys air at a suction pressure, wherein: i. the motor chamber pressure is greater than the ambient atmosphere pressure, ii. the ambient atmosphere pressure is greater than the electrical chamber pressure, iii. the electrical chamber pressure is greater than the plenum pressure, and iv. the plenum pressure is greater than the suction pressure. 16. The central vacuum system of claim 12, wherein the plenum is above the electrical chamber and the motor chamber, and the suction chamber is below the electrical chamber and the motor chamber. 17. The central vacuum system of claim 12, further comprising: a main separator interposed between the main impeller and the suction chamber to help separate the contaminants from the air that the main impeller draws from the suction chamber; and a secondary filter interposed between the motor chamber and the ambient atmosphere, wherein the secondary filter helps filter the air passing from the motor chamber to the ambient atmosphere. 18. A central vacuum system for reducing the pressure of air to less than that of an ambient atmosphere that contains contaminants, the system comprising: a canister that includes a tubular sidewall and an upper end cap, wherein the upper end cap defines a plenum inlet, and the tubular sidewall defines a suction inlet and a heat-generating chamber outlet; a first divider disposed within the canister and a second divider disposed within the canister, such that: i. the second divider, the tubular sidewall and the upper end cap help define a plenum that is in fluid communication with the ambient atmosphere via the plenum inlet, ii. the first divider and the tubular sidewall help define a suction chamber that is in fluid communication with the suction inlet, and iii. the first divider, the second divider and the sidewall help define a heat-generating chamber that is in fluid communication with the plenum and the heat-generating chamber outlet; a motor extending into the heat-generating chamber, wherein the motor heats the air therein; a main impeller coupled to the motor to help create a suction pressure within the suction chamber; a main separator interposed between the main impeller and the suction chamber to help separate the contaminants from the air that the main impeller draws from the suction chamber; a motor drive component disposed within the heat-generating chamber and being electrically coupled to the motor, wherein the motor drive component heats the air within the heat-generating chamber; and a secondary impeller coupled to the motor, wherein the secondary impeller forces air from the plenum into the heat-generating chamber, and the secondary impeller forces air from within the heat-generating chamber out through the heat-generating chamber outlet, wherein the air being forced through the heat-generating chamber by the secondary impeller helps cool the motor and helps cool the motor drive component; and a secondary filter in series flow relationship with the heat-generating chamber outlet, such that the air passing through the heat-generating chamber outlet also passes through the secondary filter. 19. The central vacuum system of claim 18, wherein the air in the plenum is cooler than the air in the electrical chamber. 20. The central vacuum system of claim 18, wherein the plenum is above the heat-generating chamber, and the heat-generating chamber is above the suction chamber. | BACKGROUND OF THE INVENTION 1. Field of the Invention The subject invention generally pertains to central vacuum systems and more particularly to a motor-cooling airflow path for such a system. 2. Description of Related Art Typical central vacuum systems comprise a blower or vacuum motor that creates a vacuum within a stationary canister. A network of tubing usually connects the canister to several wall-mounted inlet ports that are installed at various locations throughout a house or building. A flexible hose can connect a portable vacuum tool to any of the inlet ports, so the tool can be used for vacuuming a floor or other surface. The vacuum motor draws dust-laden air in series through the tool, through the hose, through the tubing network and into the canister where the dust collects. The canister can be manually opened to empty it periodically. There are two main types of central vacuum system: cyclonic and filtered. With a cyclonic system, structure within the canister directs the dust-laden air to circulate in a vortex, which employs centrifugal force to help separate the heavier dust particles from the air. A chute directs the separated dust particles to the bottom of the canister where they accumulate for later disposal. The vacuum motor draws the lighter clean air out from within the center of the vortex and discharges the air to atmosphere. Some cyclonic vacuum systems also include a filter. In comparison, a filtered system includes a main filter instead of the vortex-generating structure. The filter blocks the dust particles while allowing clean air to be discharged to atmosphere. If the filter is in the form of a bag, the dust collects in the bag. Otherwise, the dust may simply drop from the filter onto the bottom of the canister for later disposal. Many vacuum cleaners direct air across its motor to help cool the motor. The cooling air, unfortunately, may entrain carbon dust from the motor's commutator brushes and deposit a carbon residue on the exterior of the machine. To avoid this problem, some vacuum cleaners have a separate filter to help keep the carbon dust inside the machine. Examples of vacuum cleaners with a filter for carbon dust are disclosed in U.S. Pat. Nos. 5,685,894 and 5,412,837. Although such filters help keep the machine clean, they also create an airflow restriction that may lead to overheating. Consequently, there is a need for a vacuum cleaner having a cooling airflow pattern that is suitable for use with a carbon dust filter. SUMMARY OF THE INVENTION One object of some embodiments of the invention is to provide a central vacuum system with a filter for catching carbon dust released from the vacuum motor's commutator brushes. Another object of some embodiments is to cool one or more of the motor's electrical drive components (e.g., a triac) with air that has not first been preheated by the motor. Another object of some embodiments is to help prevent carbon dust from a motor's commutator brushes from contaminating a motor drive component or its associated circuit board. Another object of some embodiments is to install a vacuum motor and its electrical drive components in two separate compartments within a tubular canister of a central vacuum system. Another object of some embodiments is to cool a vacuum motor with a greater volume of air than that used for cooling the motor's electrical drive components. Another object of some embodiments is to provide a central vacuum system with a filter for carbon dust without having to install the motor's drive components on the exterior of the vacuum canister. Another object of some embodiments is to mount air-cooled electrical components within a vacuum canister and still provide a removable cover at the top of the canister for accessing the motor and other interior components. Another object of some embodiments is to cool a vacuum motor's drive components with a relatively cool, low volume of air, and to cool the motor itself with warmer air but at a higher volume. Another object of some embodiments is to provide a vacuum canister with a plenum for mixing ambient air with air that has been preheated by the motor's electrical drive components. Another object of some embodiments is to maintain the absolute air pressure of various chambers within a vacuum canister to achieve a desired airflow pattern for cooling a motor and its electrical drive components. Another object of some embodiments is to position a motor chamber and an electrical chamber between an upper plenum and a lower suction chamber to facilitate the assembly, repair and operation of a central vacuum system. Another object of some embodiments is to install a motor's electrical components inside a central vacuum canister with the cylindrical sidewall of the canister supporting the weight of the components, thereby eliminating the need for an exterior mounted electrical box. One or more of these and/or other objects of the invention are provided by a central vacuum canister that includes a motor-cooling airflow pattern that can accommodate a filter for catching carbon dust released from the motor's commutator brushes. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional side view of a vacuum canister and a schematic illustration of the remainder of a central vacuum system, wherein the canister includes a filter for capturing carbon dust from a current of air that cools the motor and its electrical drive components. FIG. 2 a cross-sectional view taken generally along line 2-2 of FIG. 1, wherein portions of a canister divider system are cutaway to show underlying detail. Also, vent holes are shown elevated from their true position to more clearly show their function. FIG. 3 is similar to FIG. 2 but showing a different embodiment where the carbon dust filter is omitted. FIG. 4 is similar to FIG. 1 but showing one of the dividers omitted. FIG. 5 is similar to FIG. 4 but showing a vacuum system that includes a different type of main filter. DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1 and 2 show a vacuum system 10 that conveys primary air 12 for cleaning (larger arrows) and conveys secondary air 14 for cooling (smaller arrows). A motor 16 drives both a main impeller 18 for moving primary air 12 and a fan or secondary impeller 20 for moving cooling air 14. A divider system 22 installed within a cylindrical or otherwise tubular canister 24 divides the canister into various chambers and directs secondary air 14 in a flow pattern suitable for cooling motor 16 and for cooling at least one motor drive component 26 (e.g., triac). The flow pattern is such that air 14 provides ample cooling even though the airflow is partially restricted by a secondary filter 28 that captures carbon dust emitted from the motor's commutator brushes 30. In operation, main impeller 18 draws air 12 from within a suction chamber 32 of canister 24, which is installed at a generally fixed location. A suction inlet 34 connects suction chamber 32 to a network of tubing 36 that leads to several wall-mounted inlet ports 38 that are installed at various locations throughout a house or building 40. A flexible hose 42 connects a portable vacuum tool 44 to any of the inlet ports 38 so that tool 44 can be used for vacuuming a floor 46 or other surfaces. To clean a surface, motor-driven impeller 18 draws dust-laden air or some other fluid from ambient atmosphere 86 in series through tool 44, through hose 42, through tubing network 36, through suction inlet 34, and into suction chamber 32 where much of the dust and other contaminants collects within a filter bag or accumulates at the bottom of canister 24. A main separator 48 installed between suction inlet 34 and main impeller 18 helps trap the contaminants within canister 24. Although separator 48 is shown as a dust-collecting filter bag, other separator designs are well within the scope of the invention. A joint connector 50 enables canister 24 to be manually opened to change or clean separator 48 or to empty the canister periodically. In this example, the dust and air are separated by filtration and the dust is collected within a filter bag; however, other methods of separation and collection can be used. After separating the dust from the air, main impeller 18 discharges cleaner air through a discharge outlet 52 that exhausts the air to ambient atmosphere 86. The term, “ambient atmosphere” refers to any gas or other fluid outside canister 24. Examples of ambient atmosphere include, but are not limited to, the air surrounding the canister's exterior, the air just upstream of suction inlet 34, and the air within building 40. In some embodiments, in order to cool motor 16 and one or more of its drive components 26, divider system 22 comprises a first divider 54, a second divider 56 and a third divider 58. First and second dividers 54 and 56 are generally round and extend diametrically across canister 24 to help define a plenum 60 at the upper end of canister 24, suction chamber 32 at the bottom, and a heat-generating chamber 62 between chambers 32 and 60. Third divider 58 extends between dividers 54 and 56 to separate heat-generating chamber 62 into an electrical chamber 64 and a motor chamber 66. Motor 16 extends into motor chamber 66, and one or more motor drive components 26 are disposed within electrical chamber 64. The term, “motor drive component” refers to any heat-generating electrical device that affects the motor's electrical power. Examples of a motor drive component include, but are not limited to, a triac, diac, power transistor, resistor, inverter, etc. Many such motor drive components are particularly suited for central vacuum systems where a variable speed motor drive is important for switching between heavy and light duty vacuuming (e.g., vacuuming floors vs. curtains). To provide a path for cooling air 14 to circulate through electrical chamber 64, motor chamber 66 and plenum 60, a tubular sidewall 68 of canister 24 defines one or more electrical chamber inlets 70, an upper end cap 72 defines a plenum inlet 74, and second divider 56 defines an opening or electrical chamber outlet 76. Tubular sidewall 68 also defines one or more motor chamber outlets 78 that lead to secondary filter 28. In cases where third divider 58 is omitted, motor chamber outlet 78 can be referred to as a heat-generating chamber outlet because the heat-generating chamber would no longer be divided into two distinct chambers (i.e., no longer a motor chamber and an electrical chamber). To cool motor 16 and component 26, and to inhibit carbon dust from being discharged to atmosphere, secondary impeller 20 draws air 14 from plenum 60, through a secondary impeller inlet 80, and into motor chamber 66. Impeller 20 forces air 14 across motor 16 where some of air 14 passes between the motor's stator 82 and rotor 84 and other portions of air 14 pass out over the top of stator 82 near the motor's commutator brushes 30. After cooling motor 16, air 14 travels from motor chamber 66, through motor chamber outlet 78, through secondary filter 28, and out to ambient atmosphere 86. Secondary filter 28 helps capture airborne carbon dust to ensure that air 14 being exhausted to atmosphere is sufficiently clean. To supply plenum 60 with air, impeller 20 creates a negative pressure (below atmospheric pressure) within plenum 60, which draws ambient air into plenum 60 through plenum inlet 74. Electrical chamber outlet 76 allows the negative pressure in plenum 60 to also draw in 14 air that has been preheated by component 26 in electrical chamber 64. Thus, plenum 60 receives a mixture of ambient air and preheated air, wherein secondary impeller inlet 80 delivers the mixture to motor chamber 66. To cool motor drive component 26, the air entering plenum 60 through electrical chamber outlet 76 reduces the pressure within electrical chamber 64 such that ambient air is drawn into chamber 64 via electrical chamber inlet 70. Thus, air 14 travels in series through electrical chamber inlet 70, through electrical chamber 64 to cool component 26, and out through electrical chamber outlet 76 to mix with ambient air in plenum 60. A bracket 88 attached to sidewall 68 supports motor drive component 26 at a position where air 14 entering through electrical chamber inlet 70 can pass directly across and around component 26. The flow of air 14 through the upper portion of canister 24 is such that the motor chamber pressure is greater than the ambient atmosphere pressure, the ambient atmosphere pressure is greater than the electrical chamber pressure, the electrical chamber pressure is greater than the plenum pressure, and the plenum pressure is greater than the suction pressure in suction chamber 32. The term, “pressure” pertains to absolute pressure rather than gage pressure, thus even air below atmospheric pressure (e.g., below 14.7 psi) can be considered to have a positive absolute pressure. The electrical chamber inlet 70 enables component 26 to be cooled by relatively cool ambient air that is generally not preheated by motor 16. Also, the influx of ambient air through plenum inlet 74 allows motor 16 to receive at least some fresh air that has not first passed across component 26. Moreover, component 26 being upstream of motor 16 helps prevent the motor brush's carbon dust from contaminating component 26 or its associated circuit board. Since electrical chamber 64 receives unheated ambient air through electrical chamber inlet 70, and motor 16 receives a slightly warmer mixture of air, it may be desirable to have the flow rate of air 14 passing through motor chamber 66 be slightly greater than that passing through electrical chamber 64, which in fact is the case with vacuum system 10. By locating electrical chamber 64 along the side of canister 24, upper end cap 72 can be removed via a joint 90 without disturbing any electrical connections that feed into canister 24. Examples of such electrical connections include, but are not limited to, a power cord 92 from a power supply 94 (e.g., wall outlet), control-wiring 96 from a control panel 98, a fuse 100, etc. In a currently preferred embodiment, the electrical connections are supported by the same bracket 88 that supports motor drive component 26. In another embodiment, shown in FIG. 3, a vacuum system 10b is the same as vacuum system 10a; however, secondary filter 28 is omitted. Without filter 28, motor chamber outlet 78 exhausts unfiltered air 14 directly to atmosphere. Although carbon dust may be released, removing filter 28 may increase the cooling of motor 16 and component 26. In another embodiment, shown in FIG. 4, a vacuum system 10c is similar to vacuum system 10a; however, third divider 58, electrical chamber inlet 70 and electrical chamber outlet 76 are omitted. Without third divider 58, motor 16 and drive component 26 share the same space within heat-generating chamber 62. In this case, secondary impeller 20 forces cooling air 14 to travel in series from ambient atmosphere 86, through plenum inlet 74, through plenum 60, through secondary impeller inlet 80, into heat-generating chamber 62 to cool motor 16 and component 26, through heat-generating chamber outlet 78, through secondary filter 28 to impede carbon dust, and back out to ambient atmosphere 86. In another embodiment, shown in FIG. 5, a vacuum system 10d is the same as vacuum system 10c; however, main separator 48 (in the form of a bag) is replaced by another main filter 102 of a different shape. With filter 102, dust collects at the bottom of the vacuum canister. In another embodiment, shown in FIG. 6, a vacuum system 10e is similar to systems 10c and 10d; however vacuum system 10e separates contaminants from air 12 using a separator in the form of a vortex-generating cylinder 104 installed within a cylindrical canister 106. A suction inlet 34′ leading tangentially into canister 106 directs air 12 into a downward circular motion around cylinder 104. Centrifugal force separates the contaminants from air 12 by slinging the heavier contaminating particles and against the interior wall of canister 106. A funnel 108 then directs the separated contaminants to the bottom of canister 106 for later disposal. Once the contaminants are separated from the air, the cleaner air travels up through a central portion of cylinder 104. From there, impeller 18 forces the now cleaner air out through discharge outlet 52. Although the invention is described with reference to a preferred embodiment, it should be appreciated by those of ordinary skill in the art that various modifications are well within the scope of the invention. The separators of FIGS. 5 and 6, for example, can also be used in the vacuum systems illustrated in FIG. 1. Therefore, the scope of the invention is to be determined by reference to the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The subject invention generally pertains to central vacuum systems and more particularly to a motor-cooling airflow path for such a system. 2. Description of Related Art Typical central vacuum systems comprise a blower or vacuum motor that creates a vacuum within a stationary canister. A network of tubing usually connects the canister to several wall-mounted inlet ports that are installed at various locations throughout a house or building. A flexible hose can connect a portable vacuum tool to any of the inlet ports, so the tool can be used for vacuuming a floor or other surface. The vacuum motor draws dust-laden air in series through the tool, through the hose, through the tubing network and into the canister where the dust collects. The canister can be manually opened to empty it periodically. There are two main types of central vacuum system: cyclonic and filtered. With a cyclonic system, structure within the canister directs the dust-laden air to circulate in a vortex, which employs centrifugal force to help separate the heavier dust particles from the air. A chute directs the separated dust particles to the bottom of the canister where they accumulate for later disposal. The vacuum motor draws the lighter clean air out from within the center of the vortex and discharges the air to atmosphere. Some cyclonic vacuum systems also include a filter. In comparison, a filtered system includes a main filter instead of the vortex-generating structure. The filter blocks the dust particles while allowing clean air to be discharged to atmosphere. If the filter is in the form of a bag, the dust collects in the bag. Otherwise, the dust may simply drop from the filter onto the bottom of the canister for later disposal. Many vacuum cleaners direct air across its motor to help cool the motor. The cooling air, unfortunately, may entrain carbon dust from the motor's commutator brushes and deposit a carbon residue on the exterior of the machine. To avoid this problem, some vacuum cleaners have a separate filter to help keep the carbon dust inside the machine. Examples of vacuum cleaners with a filter for carbon dust are disclosed in U.S. Pat. Nos. 5,685,894 and 5,412,837. Although such filters help keep the machine clean, they also create an airflow restriction that may lead to overheating. Consequently, there is a need for a vacuum cleaner having a cooling airflow pattern that is suitable for use with a carbon dust filter. | <SOH> SUMMARY OF THE INVENTION <EOH>One object of some embodiments of the invention is to provide a central vacuum system with a filter for catching carbon dust released from the vacuum motor's commutator brushes. Another object of some embodiments is to cool one or more of the motor's electrical drive components (e.g., a triac) with air that has not first been preheated by the motor. Another object of some embodiments is to help prevent carbon dust from a motor's commutator brushes from contaminating a motor drive component or its associated circuit board. Another object of some embodiments is to install a vacuum motor and its electrical drive components in two separate compartments within a tubular canister of a central vacuum system. Another object of some embodiments is to cool a vacuum motor with a greater volume of air than that used for cooling the motor's electrical drive components. Another object of some embodiments is to provide a central vacuum system with a filter for carbon dust without having to install the motor's drive components on the exterior of the vacuum canister. Another object of some embodiments is to mount air-cooled electrical components within a vacuum canister and still provide a removable cover at the top of the canister for accessing the motor and other interior components. Another object of some embodiments is to cool a vacuum motor's drive components with a relatively cool, low volume of air, and to cool the motor itself with warmer air but at a higher volume. Another object of some embodiments is to provide a vacuum canister with a plenum for mixing ambient air with air that has been preheated by the motor's electrical drive components. Another object of some embodiments is to maintain the absolute air pressure of various chambers within a vacuum canister to achieve a desired airflow pattern for cooling a motor and its electrical drive components. Another object of some embodiments is to position a motor chamber and an electrical chamber between an upper plenum and a lower suction chamber to facilitate the assembly, repair and operation of a central vacuum system. Another object of some embodiments is to install a motor's electrical components inside a central vacuum canister with the cylindrical sidewall of the canister supporting the weight of the components, thereby eliminating the need for an exterior mounted electrical box. One or more of these and/or other objects of the invention are provided by a central vacuum canister that includes a motor-cooling airflow pattern that can accommodate a filter for catching carbon dust released from the motor's commutator brushes. | 20050120 | 20080805 | 20060720 | 67205.0 | A47L538 | 0 | THOMAS, DAVID B | CENTRAL VACUUM SYSTEM WITH SECONDARY AIRFLOW PATH | SMALL | 0 | ACCEPTED | A47L | 2,005 |
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11,039,282 | ACCEPTED | Distiller with pressure-difference maintenance | A distillation unit (10) employs a fluid circuit (FIG. 8) in which a counterflow heat exchanger (102, 104, 106, 108, 110) transfers heat from condensate and concentrate to feed liquid to be distilled. The pumping system (100, 238) that drives fluid through the circuit is arranged to keep the pressure in the counterflow heat exchanger's condensate higher than that in its feed-liquid passage. This tends to discourage the contamination that could otherwise occur in the concentrate if the fluid isolation ordinarily maintained between those passages is compromised. | 1. For distilling a liquid, a system comprising: A) a fluid circuit; B) an evaporator/condenser unit disposed in the fluid circuit, including a feed-liquid inlet and a condensate outlet, and operable to receive feed liquid at its feed-liquid inlet, cause the feed liquid to evaporate into a vapor, condense the vapor into a condensate, and discharge the condensate from its condensate outlet; C) a counterflow heat exchanger providing a feed-fluid passage and a condensate passage separated from the feed-fluid passage by a divider that conducts heat from the condensate passage to the feed-fluid passage when the temperature of the fluid in the condensate passage is greater than the temperature of the fluid in the feed-fluid passage, said counterflow heat exchanger being so disposed in the fluid circuit that the fluid circuit provides fluid communication between the condensate outlet of the evaporator/condenser unit and the condensate passage of the counterflow heat exchanger and further provides fluid communication between the feed-liquid inlet of the evaporator/condenser unit and the feed-fluid passage of the counterflow heat exchanger; and D) a pumping system, disposed in the fluid circuit, that drives fluid through the fluid circuit, wherein the fluid circuit's flow resistance is such as to keep the pressure in the condensate passage exchanger greater than the pressure in the feed-fluid passage. 2. A system as defined in claim 1 wherein: A) the counterflow heat exchanger includes a plurality of counterflow-heat-exchanger modules, each of which provides a respective module feed-liquid passage and a module condensate passage separated from the feed-liquid passage by a divider that is so thermally conductive as to transfer heat from the condensate passage to the feed-liquid passage when the temperature of the fluid in the condensate passage is greater than the temperature of the fluid in the feed-liquid passage; and B) the fluid circuit connects the module feed-fluid passages in series and connects the module condensate passages in series. 3. A system as defined in claim 1 wherein: A) the evaporator/condenser unit additionally includes a concentrate outlet and discharges from its concentrate outlet feed liquid that has not evaporated into a vapor; B) the counterflow heat exchanger further provides a concentrate passage separated from the feed-fluid passage by a divider that conducts heat from the concentrate passage to the feed-fluid passage when the temperature of the fluid in the concentrate passage is greater than the temperature of the fluid in the feed-fluid passage; and C) the fluid circuit provides fluid communication between the concentrate outlet of the evaporator/condenser unit and the concentrate passage of the counterflow heat exchanger. 4. A system as defined in claim 1 wherein the fluid circuit includes a pressure-maintenance valve disposed therein downstream of the condensate passage and operable to maintain a flow resistance high enough that the pressure the in the condensate passage exchanger is greater than the pressure in the feed-fluid passage. 5. For distilling a liquid, a method comprising: A) providing a fluid circuit in which is disposed: i) an evaporator/condenser unit that includes a feed-liquid inlet and a condensate outlet; ii) a counterflow heat exchanger providing a feed-fluid passage and a condensate passage separated from the feed-fluid passage by a divider that is so thermally conductive as to conduct heat from the condensate passage to the feed-fluid passage when the temperature of the fluid in the condensate passage is greater than the temperature of the fluid in the feed-fluid passage, said counterflow heat exchanger being disposed in the fluid circuit that the fluid circuit provides fluid communication between the condensate outlet of the evaporator/condenser unit and the condensate passage of the counterflow heat exchanger and further provides fluid communication between the feed-liquid inlet of the evaporator/condenser unit and the feed-fluid passage of the counterflow heat exchanger; and B) feeding liquid through the feed-liquid passage to the evaporator/condenser unit's feed-liquid inlet; C) employing the evaporator/condenser unit to cause one of the feed liquid received at the evaporator/condenser unit's feed-liquid inlet to evaporate into a vapor, condense the vapor into a condensate, and discharge the condensate from its condensate outlet to flow through the counterflow heat exchanger's condensate passage; and D) keeping the pressure condensate passage of the counterflow heat exchanger greater than the pressure in the feed-fluid passage of the counterflow heat exchanger. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of co-pending U.S. patent application Ser. No. 10/864,746, filed on Jun. 9, 2004, by William H. Zebuhr for a Distiller Employing Cyclical Evaporation-Surface Wetting, which is a divisional of U.S. patent application Ser. No. 09/765,263, filed on Jan. 18, 2001, by William H. Zebuhr for a Distiller Employing Cyclical Evaporation-Surface Wetting and issued a U.S. Pat. No. 6,802,941. It is also related to commonly assigned U.S. Pat. No. 6,689,251 to William H. Zebuhr entitled Cycled-Concentration Distiller, abandoned U.S. patent application Ser. No. 09/765,260 of William H. Zebuhr entitled Distiller Employing Separate Condensate and Concentrate Heat-Exchange Paths, and U.S. patent application No. 09/765,475 of William H. Zebuhr entitled Distiller Employing Recirculant-Flow Filter Flushing, all of which were filed on Jan. 18, 2001, and are hereby incorporated by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is directed to distillation. It has particular, but not exclusive, application to systems that purify water by distillation. 2. Background Information One of the most effective techniques for purifying water is to distill it. In distillation, the water to be purified is heated to the point at which it evaporates, and the resultant vapor is then condensed. Since the vapor leaves almost all impurities behind in the input, feed water, the condensate that results is typically of a purity much higher in most respects than the output of most competing purification technologies. But the amount of heat energy that needs to be imparted to produce an acceptable rate of evaporation is high, so distillation is expensive if most of the energy is not recovered. For this reason, distillers that employ the invention to be described below employ heat exchangers such as counterflow heat exchangers to recover heat from the distillation operation's condensate and/or concentrate output. They do so by conducting that heat to incoming feed liquid, which needs to be heated for distillation. Such energy recovery is crucial if any efficiency is to be achieved. But condensate purity can be compromised if defects occur in, say, a counterflow heat exchanger's divider element that conducts heat between the feed liquid and the condensate but ordinarily prevents fluid communication between the passages in which those two fluids flow. Age, corrosion, or other factors, for example, may cause the divider to develop a hole small enough to go unnoticed but large enough to permit some of the untreated feed liquid to mix with the previously purified condensate. SUMMARY OF THE INVENTION But I have recognized that such contamination can largely be avoided if the system's fluid circuit is so arranged as to keep the pressure in the heat exchanger's condensate passage higher than that in its feed-liquid passage. Under such circumstances, the direction of any leakage that results from such heat-exchanger defects will tend to be from the condensate passage to the feed-liquid passage, not from the feed-liquid passage to the condensate passage. Such pressure-difference maintenance can be accomplished readily by, for example, making the flow resistance downstream of the condensate passage high enough. In the embodiment described below, the expedient used for this purpose is a downstream pressure-maintenance valve. BRIEF DESCRIPTION OF THE DRAWINGS The invention description below refers to the accompanying drawings, of which: FIG. 1 is a front isometric view of a distillation unit that employs the present invention's teachings; FIG. 2 is a cross-sectional view taken through the distillation unit; 2 FIG. 3 is a plan view of one of the heat-exchange plates employed in the distillation unit's rotary heat exchanger; FIG. 4 is a cross-sectional view through two such plates taken at line 4-4 of FIG. 3; FIG. 5 is a diagram of the fluid flow through the rotary heat exchanger's evaporation and condensation chambers; FIG. 6 is a broken-away perspective view of the distillation unit's compressor; FIG. 7 is a broken-away cross-sectional view of one side of the compressor and the rotary heat exchanger's upper portion showing the fluid-flow paths between them; FIG. 8 is schematic diagram of the distillation unit's fluid circuit; FIG. 9 is a perspective view of the vapor-chamber base, main scoop tubes, and irrigation arms that the distillation unit employs; FIG. 10 is a plan view of the elements that FIG. 9 depicts; FIG. 11 is a cross-sectional view taken at line 11-11 of FIG. 10; FIG. 12 is a cross-sectional view taken at line 12-12 of FIG. 10; FIG. 13 is a cross-sectional view of one of the spray arms, taken at line 13-13 of FIG. 12; FIG. 14 is a broken-away perspective view of the distillation unit's transfer valve and related elements; FIG. 15 is a broken-away perspective view of the distillation unit's transfer pump; FIG. 16 is a broken-away isometric view of the distillation unit's filter assembly; FIG. 17 is a further broken-away perspective view of the transfer valve illustrating the valve crank and its actuator in particular; FIG. 18 is a view similar to FIG. 12, but showing the transfer valve in its elevated position; FIG. 19 is an isometric view of one of the distillation unit's counterflow-heat-exchanger modules; and FIG. 20 is a cross-sectional view of that heat-exchanger module. DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT FIG. 1 is an exterior isometric view of a distillation unit in which the present invention's heat-exchanger-irrigation approach can be employed. In general, the distillation unit 10 includes a feed inlet 12 through which the unit draws a feed liquid to be purified, typically water containing some contamination. The unit 10 purifies the water, producing a pure condensate at a condensate outlet 14. The volume rate of condensate produced by the unit 10 will in most cases be only slightly less than that of the feed liquid entering inlet 12, nearly all the remainder being a small stream of concentrated impurities discharged through a concentrate outlet 16. The unit also may include a safety-drain outlet 18. The illustrated unit is powered by electricity, and it may be remotely controlled or monitored. For this reason, electrical cables 20 are also provided. In the illustrated embodiment, the distillation unit 10 is intended for high-efficiency use, so it includes an insulating housing 22. But the present invention's teachings are applicable to a wide range of heat-exchanger applications, not all of which would typically employ such a housing. FIG. 2 is a simplified cross-sectional view of the distillation unit. It depicts the housing 22 as having a single-layer wall 24. In single-layer arrangements, the wall is preferably made of low-thermal-conductivity material. Alternatively, it may be a double-layer structure in which the layers are separated by insulating space. The present invention is an advantageous way to supply feed liquid to the unit's heat exchanger 32. While the present invention's teachings can be employed to feed a wide variety of heat exchangers, the drawings illustrate a particular type of rotary heat exchanger for the sake of concreteness. As will be explained in more detail directly, the illustrated embodiment's rotary heat exchanger is essentially a group of stacked plates, one plate 34 of which will be described in more detail in connection with subsequent drawings. That heat exchanger 32 is part of an assembly that rotates during operation and includes a generally cylindrical shell 36 driven by a motor 38. The rotating assembly's shell 36 is disposed inside a stationary vapor-chamber housing 40 on which is mounted a gear housing 42 that additionally supports the motor 38. The vapor-chamber housing 40 in turn rests in a support omitted from the drawing for the sake of simplicity. As FIG. 3's exemplary heat-exchanger plate 34 illustrates, each plate is largely annular; it may have an outer diameter of, say, 8.0 inches and an inner diameter of 3.35 inches. Each plate is provided with a number of passage openings 46. FIG. 4, which is a cross section taken at line 4-4 of FIG. 3, shows that the passage openings are formed with annular lips 48 that in alternating plates protrude upward and downward so that, as will explained in more detail presently, they mate to form passages between the heat exchanger's condensation chambers. To form alternating condensation and evaporation chambers, the heat-exchanger plates are provided with annular flanges 50 at their radially inward edges and annular flanges 52 at their radially outward edges. Like the passage lips 48, these flanges 50 and 52 protrude from their respective plates, but in directions opposite those in which the passage lips 48 protrude. FIG. 5, which depicts the radially inward part of the heat exchanger on the left and the radial outward part on the right, shows that successive plates thereby form enclosed condensation chambers 54 interspersed with open evaporation chambers 56. A recently tested prototype of the heat exchanger employs 108 such plate pairs. As will be explained in more detail below, a sprayer in the form of a stationary spray arm 58 located centrally of the spinning heat-exchanger plates sprays water to be purified onto the plate surfaces that define the evaporation chambers 56. (The use of the term spray is not intended to imply that the water is necessarily or preferably applied in droplets, although some embodiments may so apply the liquid.) That liquid absorbs heat from those surfaces, and some of it evaporates. FIG. 2's compressor 60 draws the resultant vapor inward. FIG. 6 depicts compressor 60 in more detail. The compressor spins with the rotary heat exchanger and includes a (spinning) compressor cylinder 62 within which a mechanism not shown causes two pistons 64 and 66 to reciprocate out of phase with each other. As a piston rises, its respective piston ring 68 or 70 forms a seal between the piston and the compressor cylinder 62's inner surface so that the piston draws vapor from the heat exchanger's central region. As a piston travels downward, on the other hand, its respective piston ring tends to lift off the piston surface and thereby break the seal between the cylinder wall and the pistons. When their respective pistons are traveling downward, annular piston-ring stops 72 and 74, which respective struts 76 and 77 secure to respective pistons 64 and 66, drag respective piston rings 68 and 70 downward after the seal has been broken. The piston rings and stops thus leave clearances for vapor flow past the pistons as they move downward, so a downward-moving piston does not urge the vapor back downward as effectively as an upward-moving piston draws it upward. Additionally, the pistons reciprocate so out of phase with each other that there is always one piston moving upward, and thereby effectively drawing the vapor upward, while the other is returning downward. As will be explained in more detail below, the vapor thus driven upward by the pistons 64 and 66 cannot pass upward beyond the compressor's cylinder head 78, but slots 80 formed in the compressor wall's upper lip provide paths by which the vapor thus drawn from the heat exchanger's central region can be driven down through an annular passage 82 formed between the compressor cylinder 62's outer surface and the rotating-assembly shell 36. This passage leads to openings 83 in an annular cover plate 84 sealed by O-rings 85a and 85b between the compressor cylinder 62 and the rotating-assembly shell 36. The openings 83 register with the openings 46 (FIG. 3) that form the passages between the condensation chambers. In short, the compressor cylinder 62, the cylinder head 78, and the rotating-assembly shell 36 cooperate to form a guide that directs vapor along a vapor path from FIG. 5's evaporation chambers 56 to its condensation chambers 54. And the compressor compresses the vapor that follows this path, so the vapor pressure in the condensation chambers 54 is higher than that in the evaporation chambers 56, from which the compressor draws the vapor. The boiling point in the condensation chambers therefore is also higher than in the evaporation chambers. So the heat of vaporization freed in the condensation chambers diffuses to the (lower-temperature) evaporation chambers 56. In the illustrated embodiment, the rotating assembly rotates at a relatively high rate of, say, 700 to 1000 rpm. The resultant centrifugal force causes the now-purified condensate to collect in the outer ends of the condensation chambers, between which it can flow through the passages that the heat-exchanger-plate openings 46 form. As FIG. 7 shows, the condensate therefore flows out through the openings 83 in the top of the heat exchanger and travels along the channel 82 by which the compressed vapor flowed into the heat exchanger. Like the compressed vapor, the condensate can flow through the openings 80 in the compressor wall's lip. But the condensate can also flow past the cylinder head 78 because of a clearance 86 between that cylinder head 78 and the rotating-assembly shell, whereas the condensate's presence in that clearance prevents the compressed vapor from similarly flowing past the cylinder head. An O-ring 88 seals between the rotating-assembly shell 36 and a rotating annular channel-forming member 90 secured to the cylinder head 78, but spaced-apart bosses 92 formed in the cylinder head 78 provide clearance between the cylinder head and the channel member so that the condensate, urged by the pressure difference that the compressor imposes, can flow inward and into channel member 90's interior. Like the cylinder head 78 to which it is secured, the channel-forming member 90 spins with the rotary heat exchanger to cause the purified condensate that it contains to collect under the influence of centrifugal force in the channel's radially outward extremity. The spinning condensate's kinetic energy drives it into a stationary scoop tube 94, from which it flows to FIG. 1's condensate outlet 14 by way of a route that will be described in due course. While the scoop tube 94 is thus removing the liquid condensate that has formed in the condensation chambers, centrifugal force drives the unevaporated feed liquid from the evaporation chambers to form an annular layer on the part of the rotating-assembly wall 36 below plate 84: that wall thus forms a liquid-collecting sump. Another scoop tube, which will be described below, removes this unevaporated liquid for recirculation through the rotary heat exchanger. Before we deal with the manner in which the recirculation occurs, we summarize the overall fluid circuit by reference to FIG. 8. A pump 100 draws feed liquid from the feed inlet 12 and drives it to the cold-water inlets 102C—IN and 104C—IN of respective counterflow-heat-exchanger modules 102 and 104. Those modules guide the feedwater along respective feed-water paths to respective cold-water outlets 102C—OUT and 104C—OUT. In flowing along those paths, the feedwater is in thermal communication with counterflows that enter those heat exchangers at hot-water inlets 102H—IN and 104H—IN and leave through hot-water outlets 102H—OUT and 104H—OUT, as will be explained in more detail below, so it is heated. (The terms hot and cold here respectively refer to the fluid flows from which and to which heat is intended to flow in the counterflow heat exchangers. They are not intended to refer to absolute temperatures; the liquid leaving a given counterflow heat exchanger's “cold”-water outlet, for instance, will ordinarily be hotter than the liquid leaving its “hot”-water outlet.) For reasons that will be set forth below, counterflow-heat-exchanger module 104 receives a minor fraction of the feed-water flow driven by the pump 100. Its volume flow rate is therefore relatively low, and the temperature increase of which it is capable in a single pass is relatively high as a consequence. For modularity purposes, counterflow-heat-exchanger module 102 in the illustrated embodiment is essentially identical to counterflow-heat-exchanger module 104, but it receives a much higher volume flow rate, and the temperature increase that it can impart is correspondingly low. So the cold-water flow through counterflow-heat-exchanger module 102 also flows serially through further modules 106, 108, and 110 to achieve a temperature increase approximately equal to module 104's. The series-connected modules' output from outlet 110C—OUT is fed to a degasser 112, as is the single heat exchanger 104's output from outlet 104C—OUT For the sake of simplicity, FIG. 2 omits the degasser, but the degasser would typically enclose the motor 38 to absorb heat from it. The degasser thus further heats the liquid. Together with the heat imparted by the counterflow heat exchangers, this heat may be enough to raise the feed-liquid temperature to the level required for optimum evaporator/condenser action when steady-state operation is reached. From a cold start, though, a supplemental heat source such as a heating coil (not shown) would in most cases contribute to the needed heat. The residence time in the degasser is long enough to remove most dissolved gasses and volatiles from the stream. The thus-degassed liquid then flows to a filter assembly 114, where its flow through a filter body 116 results in particulate removal. The resultant filtered liquid flows from the filter body 116 to an annular exit chamber 118, from which it issues in streams directed to two destinations. Most of that liquid flows by way of tube 119 to a nozzle 120. As FIG. 9 shows, nozzle 120 delivers the filtered feed liquid to the rotating-assembly shell 36's inner surface, where it joins the liquid layer formed by the liquid that has flowed through the evaporation chambers without evaporating. Only a minor fraction of the liquid that flows into the evaporation chambers evaporates in those chambers in one pass, so most of it contributes to the rotating layer, whereas the feed nozzle 120 delivers only enough liquid to that layer to replenish the fluid that has escaped by evaporation. Stationary scoop tubes 122 and 124 scoop liquid from this rotating layer. The scooped liquid's kinetic energy drives it along those tubes, which FIG. 10 shows in plan view and FIGS. 11 and 12 show in cross-sectional views respectively taken at lines 11-11 and 12-12 of FIG. 10. To minimize the kinetic energy's dissipation, each scoop tube bends gradually to a predominantly radial direction. Also, each scoop tube is relatively narrow at its entrance but widens gradually to convert some of the liquid's dynamic head into static head. Those tubes guide the thus scooped liquid into an interior chamber 126 (FIG. 11) of a transfer-valve assembly 128. Ordinarily, a transfer-valve member 130 is oriented as FIG. 12 shows. In this orientation it permits flow from the interior chamber 126 through entry ports 132 into spray arms 58 but prevents flow through a port 134 into a conduit 136 that leads to an upper entrance of FIG. 8's filter assembly 114. The static head drives the liquid up the spray arms. FIG. 13, which is cross-sectional view taken at line 13-13 of FIG. 12, shows that each of the spray arms 58 forms a longitudinal slit 138. These slits act as nozzles from which the (largely recirculated) liquid sprays into the evaporation chambers 56 depicted in FIG. 5. In short, the liquid-collecting inner surface of the rotating-assembly shell 36, the scoop tubes 122 and 124, the transfer-valve assembly 128, and the spray arms 58 form a guide that directs unevaporated liquid along a recirculation path that returns it to the evaporation chambers 56. And, since FIG. 8's nozzle 120 supplements the recirculating liquid with feed liquid, this guide cooperates with the main pump 100, the counterflow heat exchangers 102, 104, 106, 108, and 110, the degasser 112, the filter assembly 114, and the tubes that run between them as well as tube 118 and nozzle 120 to form a further guide. This further guide directs feed liquid along a make-up path from the feed inlet 12 to the evaporation chambers 56. Now, so long as its evaporator-chamber surfaces stay wetted, heat-transfer efficiency in the rotary heat exchanger is greatest when the water film on these surfaces is thinnest. The flow volume through the spray arms 58 should therefore be so controlled as to leave that film as thin as possible. In the illustrated embodiment, the flow rate through those spray arms is chosen to be just high enough to keep the surfaces from drying completely between periodic wetting sprays from a scanner 140 best seen in FIG. 9. The scanner includes two scanner nozzles 142 and 144 that provide a supplemental spray at two discrete (but changing) heights within the rotary heat exchanger. The nozzles' heights change because a drive rod 146 reciprocates, in a manner that will presently be described in more detail, to raise and lower a yoke 148 from which the scanner 140 extends. Control of the scanner feed is best seen in FIG. 14, which is a cross-sectional view, with parts removed, of the vapor-chamber housing 40's lower interior. FIG. 14 depicts the valve member 130 in the closed state, but when the valve member 130 is in its opposite, open state, it permits flow not only into the spray tubes' ports 132 but also into a path through a separate feed conduit 150 by way of an internal passage not shown into a vertically extending tube 152. A telescoping conduit 154 that slides in tube 152 conducts the flow, as best seen in FIG. 9, through the yoke 148 and into the scanner 140. So these elements guide liquid along a further branch of the recirculation and make-up paths. As the reciprocating rod 146 drives the yoke 148 and thereby the scanner 140 up and down, successive evaporation chambers momentarily receive a supplemental liquid spray. This spray is enough to wet the evaporator surfaces if they have become dry, or at least to prevent them from drying as they would if they were sprayed only through the spray arms 58. The flow rate experienced by each of the evaporation chambers is therefore cyclical. The steady flow from the spray arms can be low enough not to keep the surfaces wetted by itself. Indeed, the cyclical spray can keep the surfaces wetted even if the average flow rate that results when the supplemental scanner spray is taken into account would not be great enough to keep the surface wetted if it were applied steadily. Under testing conditions that I have employed, for example, the irrigation rate required to keep the plates wetted is about 4.0 gal./hr./plate if the irrigation rate is kept constant. But I have been able to keep the heat-transfer surfaces wetted when the spray arms together sprayed 216 gal./hr. on 216 plates, or only 1.0 gal/hr./plate. True, this spray was supplemented by the spray from the scanner. But the scanner nozzles together contributed only 30 gal./hr. Since the scanner nozzles together overlap two evaporation chambers in my prototype so as to spray an average of four plates at a time, this meant that the scanner sprayed each plate for about {fraction (4/216)}=1.9% of the time at about 30 gal./hr.÷4 plates=7.5 gal./hr./plate. Although the resultant peak irrigation rate was therefore 8.5 gal./hr./plate, which exceeds the constant rate required to keep the plates wetted, the average irrigation rate was only 1.14 gal./hr./plate, or only 28% of that constant rate of 4.0 gal./hr./plate. Such a low rate contributes to heat-exchanger efficiency, because it permits the average film thickness to be made less without drying than would be possible with only a steady spray. While it is not necessary to use these particular irrigation rates, most embodiments of the present invention will employ average rates no more than half the constant rate required for wetting, while the peak rate will exceed that constant rate. The manner in which the scanner 140's reciprocation is provided is not critical to the present invention; those skilled in the art will recognize many ways in which to cause reciprocation. But the way in which the illustrated embodiment provides the reciprocation is beneficial because it takes advantage of the mechanisms used to refresh the rotary-heat-exchanger fluid and to back flush the filter. To understand those mechanisms, it helps to refer to FIG. 14. FIG. 14 shows that the transfer-valve assembly 128 is provided on a vapor-chamber base 160 sealingly secured to the vapor-chamber housing 40's lower annular lip 162. Together that lip and the vapor-chamber base can be thought of as forming a secondary, stationary sump that catches any spillage from the main, rotating sump. The heating coil mentioned above for use on startup may be located in that sump and raise the system to temperature by heating sump liquid whose resultant vapor carries the heat to the remainder of the system. Among the several features that the vapor-chamber base 160 forms is a vertical transfer-pump port 164, through which the drive rod 146 extends. That rod extends into a transfer pump 166 that FIG. 14 omits but FIG. 15 illustrates in cross section. The transfer pump 166 includes an upper cylinder half 168 that forms a cylindrical lip 169, which mates with the transfer-pump port 164 of FIG. 14. It also forms a flange 170 by which a bolt 172 secures it to a corresponding flange 174 formed on a lower cylinder half 176. FIG. 15 also depicts a mounting post 178, which is one of two that are secured to FIG. 14's vapor-chamber base 160 and support the transfer pump 116 by means of flanges, such as flange 180, formed on the upper cylinder half 168. A piston 182 is movably disposed inside the transfer-pump cylinder that halves 168 and 176 form, and a spring 184 biases the piston 182 into the position that FIG. 15 depicts. As that drawing illustrates, the drive rod 146 is so secured to the piston 182 as to be driven by it as the piston reciprocates in response to spring 184 and fluid flows that will now be described by reference to FIG. 8. It will be recalled that the filter assembly 114's output is divided between two flows. In addition to the liquid-make-up flow through tube 119 to the feed nozzle 120, there is a second, smaller flow through another tube 186. This tube leads to a channel, not shown in FIG. 14, that communicates with an upper section 188, which FIG. 14 does show, of the transfer-pump port 164. During most of its operating cycle, the piston 182 shown in FIG. 15 moves slowly downward in response to the force of its bias spring 184 and thereby draws liquid from FIG. 8's tube 186 through port 164 into the portion of the transfer pump's interior above the piston 182. As will be seen, this portion serves as a refresh-liquid reservoir, and the components that guide feed liquid from FIG. 8's feed inlet 12 through the filter assembly 114 cooperate with tube 186 and port 164 to form a guide that directs feed liquid along a feed-liquid-storage path into that reservoir. As will also be seen, the pump's lower portion serves as a concentrate reservoir. While the piston is drawing liquid into the refresh-liquid reservoir, it is expelling liquid from the concentrate reservoir through an output port 190 formed, as FIG. 15 shows, by the lower cylinder half 176. The lower cylinder half further forms a manifold 192. One outlet 194 of that manifold leads to the filter assembly 114, which FIG. 15 omits but FIG. 16 depicts in cross section. FIG. 16 shows that the filter assembly includes a check valve 196 that prevents flow into the filter assembly from manifold outlet 194. As FIG. 15 shows, the flow leaving the transfer pump from its lower outlet 190 must therefore flow through the other manifold outlet 198. FIG. 8 shows that a tube 200 receives that transfer-pump output. A flow restricter 202 in that tube limits its flow and thus the rate at which the transfer-pump piston can descend. By thus limiting the transfer-pump piston 182's rate of descent, flow restricter 202 also limits how much of the filter assembly 114's output flows through tube 186 into the transfer pump 166's upper side, with the result that the transfer pump receives only a small fraction of the filter output and thus of the output from the input pump 100. A flow divider comprising a flow junction 203 and another flow restricter 204 so controls the proportion of pump 100's output that feeds counterflow-heat-exchanger module 104's cold side that this cold-side flow approximates the hot-side flow that flow restricter 202 permits: main pump 100's output is divided in the same proportion as the transfer pump 166's output is. As was mentioned above, the resultant relatively low flow rate into module 104 is what enables the entire heat transfer to occur in a single module 104, whereas the higher flow rate through modules 102, 106, 108, and 110 necessitates, their series combination. Because of the flow restricter 202, FIG. 15's transfer-pump piston 182 moves downward under spring force at a relatively leisurely rate, taking, say, five minutes to proceed from the top to the bottom of the transfer-pump cylinder. As the piston descends, it draws the drive rod 146 downward with it, thereby causing FIG. 9's scanner nozzles 142 and 144 to scan respective halves of the rotary heat exchanger's set of evaporation chambers. At the same time, it slides an actuator sleeve 206 provided by yoke 148 along an actuator rod 208. As FIG. 17 shows, a spring mount 210 is rigidly secured to the actuator rod 208 and so mounts a valve-actuating spring 212 that the spring's tip fits in the crotch 214 of a valve crank 216. The spring engages the crank in an over-center configuration that ordinarily keeps that actuator rod 208 in the illustrated relatively elevated position. The valve crank 216 is pivotably mounted in the transfer-valve assembly and secured to FIG. 12's transfer-valve member 130 to control its state. When the valve crank 216 is in its normal, upper position depicted in FIG. 17, the transfer-valve member 130 is in the lower position, depicted in FIG. 12, in which it directs liquid from the scoop tubes 122 and 124 (FIG. 10) to flow into the spray arms 58 and scanner 140 but not into the filter inlet port 134. As FIG. 9's yoke 148 continues its descent, though, its actuator sleeve 206 eventually begins to bear against a buffer spring 218 that rests on the spring mount 210's upper end. The resultant force on the mount and thus on the actuator rod 208 overcomes the restraining force of FIG. 17's valve-actuating spring 212, causing the valve crank 216 to snap to its lower position. It thereby operates FIG. 12's valve member 130 from its position illustrated in FIG. 12 to its FIG. 18 position, in which it redirects the scoop-tube flow from the spray arms 58 to the conduit 136 that feeds the filter assembly's upper inlet 220 (FIG. 16). Now, whereas fluid ordinarily flows through the filter at only the relatively low rate required to compensate for evaporation, the flow directed by this transfer-valve actuation into the filter is the entire recirculation flow; that is, it includes all of the liquid that has flowed through FIG. 5's evaporation chambers 56 without evaporating. Since only a relatively small proportion of the liquid that is fed to the evaporation chambers actually evaporates in any given pass, the recirculation flow is many times the feed flow, typically twenty times. The pressure that this high flow causes within the filter assembly opens the filter assembly's check valve 196 (FIG. 16) and thereby permits the recirculation flow to back through the outlet 194 of FIG. 15's transfer-pump-output manifold 192 and, because of the resistance offered by flow restricter 202 (FIG. 8), back through the transfer pump's outlet 190 to the concentrate reservoir. With the transfer valve in this state, that is, the scoop tubes 122 and 124 (FIG. 10), the transfer-valve assembly 128, and the filter assembly 114 (FIG. 16) form a guide that directs concentrate from the liquid-collecting inner surface of the rotating-assembly shell 36 (FIG. 9) along a concentrate-storage path to the transfer pump's concentrate reservoir. That redirected flow flushes the filter so as to reduce its impurities load and thus the maintenance frequency it would otherwise require. It also drives the transfer-pump piston 182 (FIG. 15) rapidly upward. The piston in turn rapidly drives the feed liquid that had slowly accumulated in the transfer pump's upper, refresh-reservoir portion out through the vapor-chamber base's port 164 (FIG. 14) along a refresh path. As FIG. 14 shows, that is, it flows into ports 132 by way of a check valve 224 provided to prevent recirculation flow from entering the refresh reservoir. With that flow now redirected to the transfer pump's lower side, i.e., to the concentrate reservoir, the resultant rapid flow through the check valve 224 and ports 132 enters the spray arms 58 and scanner 140, replacing the temporarily redirected recirculation flow. All this happens in a very short fraction of the recirculation cycle. In most embodiments, the duration of this refresh cycle will be only on the order of about a second, in contrast to the recirculation cycle, which will preferably be at least fifty times as long, typically lasting somewhere in the range of two to ten minutes. The effect of thus redirecting the feed and recirculation flows is to replace the rotary heat exchanger's liquid inventory with feed liquid that has not recirculated. As was explained previously, the rotary heat exchanger continuously removes vapor from the evaporation side, leaving impurities behind and sending the vapor to the condensation side. So impurities tend to concentrate in the recirculation flow. Such impurities may tend to deposit themselves on the heat-exchange surfaces. Although the periodic surface flushing that the scanner nozzles perform greatly reduces this tendency, it is still desirable to limit the impurities concentration. One could reduce impurities in a continuous fashion, continuously bleeding off some of the recirculation flow as concentrate exhaust. But the illustrated embodiment periodically replaces essentially the entire liquid inventory on the rotary heat exchanger's evaporation side. This results in an evaporator-side concentration that can average little more than half the exhaust concentration. So less water needs to be wasted, because the exhaust concentration can be higher for a given level of tolerated concentration in the system's evaporator side. As the transfer-pump piston rises rapidly, it slides FIG. 9's actuator sleeve 206 upward rapidly, too. Eventually, the sleeve begins to compress a further buffer spring 226 against a stop 230 that the actuator rod 208 provides at its upper end. At some point, the resultant upward force on the actuator rod 208 overcomes the restraining force that FIG. 17's valve-actuating spring 212 exerts on it through the spring mount 210, and the actuator rod rises to flip the valve crank 216 back to its upper position and thus return the transfer valve 130 to its normal position, in which the recirculation flow from FIG. 9's scoop tubes 122 and 124 is again directed to the spray arms and scanner. So the unit returns to its normal regime, in which the transfer pump slowly expels concentrate from its concentrate reservoir and draws feed liquid through the feed-liquid storage path to its refresh-liquid reservoir. As FIG. 8 shows, tube 200, counterflow-heat-exchanger module 104, and a further tube 232 guide the concentrate thus expelled along a concentrate-discharge path from manifold outlet 198 to the concentrate outlet 16. To achieve approximately the same peak concentration in different installations despite differences in those installations' feed-liquid impurity levels, different refresh-cycle frequencies may be used in different installations. And, since the typical feed-liquid impurity level at a given installation may not always be known before the unit is installed—or at least until rather late in the distiller's assembly process—some embodiments may be designed to make that frequency adjustable. For example, some embodiments may make the piston travel adjustable by, for instance, making the position of a component such as FIG. 9's stop 230 adjustable. In the illustrated embodiment, though, that travel also controls scanner travel, and any travel adjustability would instead be used to obtain proper scanner coverage. So one may instead affect frequency by adjusting the force of FIG. 15's transfer-pump spring 184. This could be done by, for instance, making the piston 182's position on the drive rod 146 adjustable. Refresh-frequency adjustability could also be provided by making the flow resistance of FIG. 8's flow restricter 202 adjustable. In any case, flow restricter 204, which balances the two counterflow-heat-exchanger flows to match the relative rate of concentrate discharge, would typically also be made adjustable if the refresh-cycle frequency is. The flow restricters could take the form of adjustable bleed valves, for instance. Having now described the distillation unit's rotary heat exchanger, we will describe one of its counterflow-heat-exchanger modules. Before doing so, though, we return to FIG. 8 to complete the discussion of the fluid circuit in which those modules reside. The flow of purified liquid that issues from FIG. 7's condensate scoop tube 94 is directed to FIG. 8's accumulator 236, which the drawings do not otherwise show. The accumulator 236 receives condensate in a resiliently expandable chamber. The accumulator's output feeds heat-exchanger module 110's hot-water inlet 110H—IN to provide the hot-side flow through the serial combination of heat exchangers 110, 108, 106, and 102. A condensate pump 238 drives this flow. After being cooled by flow through the serial heat-exchanger-module combination, the cooled condensate issues from module 102's “hot”-water outlet 102H—OUT and flows through a pressure-maintenance valve 240 and the concentrate outlet 16. Valve 240 keeps the pressure in the hot sides of counterflow heat exchangers 102, 106, 108, and 110 higher than in their cold sides so that any leakage results in flow from the pure-water side to the dirty-water side and not vice versa. The main pump 100's drive is controlled in response to a pressure sensor 242, which monitors the rotary heat exchanger's evaporator-side pressure at some convenient point, such as the transfer valve's interior chamber. Finally, to accommodate various leakages, tubes to the drain outlet 18 may be provided from elements such as the pump, pressure-maintenance valve, and sump. It can be seen from the description so far that the counterflow-heat-exchanger modules 102, 104, 106, and 108 act as a temperature-transition section. The rotary-heat-exchanger part of the fluid circuit is a distiller by itself, but one that relies on a high-temperature input and produces high-temperature outputs. The counterflow-heat-exchanger modules make the transition between those high temperatures and the relatively low temperatures at the feed inlet and condensate and concentrate outlets. The counterflow-heat-exchanger modules in essence form two heat exchangers, which respectively transfer heat from the condensate and concentrate to the feed liquid. We now turn to one example of the simple type of counterflow-heat-exchanger module that this arrangement permits. FIG. 19, which is an isometric view of counterflow heat exchanger 102 with parts removed, shows tubes that provide its cold-water inlets 102C—IN and 102C—OUT. It also shows the hot-water outlet 102H—OUT but not the hot-water inlet, which is hidden. FIG. 20 is a cross section taken through the cold-water inlet 102C—IN and the hot-water outlet 102H—OUT That drawing shows that heat exchanger 102 includes a generally U-shaped channel member 250, which provides an opening 252 that communicates with the heat exchanger's “hot”-side outlet. Similar openings 254 in a cover 258 and gasket 260 (both of which FIG. 19 omits) provide the cold-water inlet 102C—IN. A folded stainless-steel heat-transfer sheet 262 provides the heat-exchange surfaces that divide the cold-water side from the hot-water side, and elongated clips 264 secure the folded sheet's flanges 266, channel-member flanges 268, cover 258, and cover gasket 260. As FIG. 19 shows, spacer combs 270 are provided at spaced-apart locations along the heat exchanger's length. One spacer comb 270's teeth 272 are visible in FIG. 20, and it can be seen that the teeth help to maintain proper bend locations in the folded heat-transfer sheet 262. Similar teeth 274 of a similar spacer comb at the opposite side of the heat-transfer sheet 262 also serve to space its bends. FIG. 19 shows the upper surfaces of diverter gaskets 278, which extend between the upper spacer combs 270 and serve to restrict the cold-water flow to regions close to the folded heat-transfer sheet 262's upper surface. FIG. 19 also shows that the module includes end plates 280 and 281. These end plates cooperate with the channel member 250, the cover 258, and the cover gasket 260 to form a closed chamber divided by the sheet 262. Additionally, the leftmost diverter gasket 278 cooperates with the end plate 280 and the cover 258 and cover gasket 260 to form a plenum 282 (FIG. 20) by which cold water that has entered through port 102C—N is distributed among the heat-exchange-surface sheet 262's several folds. End plate 280 similarly cooperates with another diverter gasket 284 (FIG. 20) to form a similar plenum 286 by which water on the hot-water side that has flowed longitudinally along the heat-exchange surfaces issues from the heat exchanger 102 by way of its hot-water outlet 102H—OUT. Incoming hot-side water and outgoing cold-side water flow through similar plenums at the other end. It can be appreciated from the foregoing description that the present invention's teachings can significantly increase an evaporator-and-condenser unit's operating efficiency. It thus constitutes a significant advance in the art. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention is directed to distillation. It has particular, but not exclusive, application to systems that purify water by distillation. 2. Background Information One of the most effective techniques for purifying water is to distill it. In distillation, the water to be purified is heated to the point at which it evaporates, and the resultant vapor is then condensed. Since the vapor leaves almost all impurities behind in the input, feed water, the condensate that results is typically of a purity much higher in most respects than the output of most competing purification technologies. But the amount of heat energy that needs to be imparted to produce an acceptable rate of evaporation is high, so distillation is expensive if most of the energy is not recovered. For this reason, distillers that employ the invention to be described below employ heat exchangers such as counterflow heat exchangers to recover heat from the distillation operation's condensate and/or concentrate output. They do so by conducting that heat to incoming feed liquid, which needs to be heated for distillation. Such energy recovery is crucial if any efficiency is to be achieved. But condensate purity can be compromised if defects occur in, say, a counterflow heat exchanger's divider element that conducts heat between the feed liquid and the condensate but ordinarily prevents fluid communication between the passages in which those two fluids flow. Age, corrosion, or other factors, for example, may cause the divider to develop a hole small enough to go unnoticed but large enough to permit some of the untreated feed liquid to mix with the previously purified condensate. | <SOH> SUMMARY OF THE INVENTION <EOH>But I have recognized that such contamination can largely be avoided if the system's fluid circuit is so arranged as to keep the pressure in the heat exchanger's condensate passage higher than that in its feed-liquid passage. Under such circumstances, the direction of any leakage that results from such heat-exchanger defects will tend to be from the condensate passage to the feed-liquid passage, not from the feed-liquid passage to the condensate passage. Such pressure-difference maintenance can be accomplished readily by, for example, making the flow resistance downstream of the condensate passage high enough. In the embodiment described below, the expedient used for this purpose is a downstream pressure-maintenance valve. | 20050120 | 20100105 | 20050609 | 73936.0 | 0 | MANOHARAN, VIRGINIA | DISTILLER WITH PRESSURE-DIFFERENCE MAINTENANCE | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,039,358 | ACCEPTED | Method and apparatus for molding composite articles | A method and apparatus for molding composite articles can include a pair of opposed mold sections having first and second molding membranes that define a mold plenum. The mold sections have a thin-skin mold section configuration. Each mold section can be filled with a gas backing. The temperature of the mold plenum can be controlled by regulating the temperature of the gas backing. | 1. A method of molding an article comprising: (a) arranging first and second rigid mold sections in a spaced apart opposed relationship; (b) attaching a first membrane to the first mold section, the first member and the first mold section defining a first chamber; (c) attaching a second membrane to the second mold section, the second member and the second mold section defining a second chamber, the first and second members further defining a mold plenum between opposing surfaces of the first and second membranes; (d) filling and pressurizing the first and second chambers with a gas backing at a first gas pressure level; (e) injecting molding fluid into the mold plenum; (f) monitoring the gas pressure within the mold plenum; and (g) regulating the gas pressure within the first and second pressure chambers during the molding of the article. 2. The method of claim 1, further including monitoring a flow rate of the molding fluid during injection into the mold plenum. 3. The method of claim 2, further including sensing at least one parameter to determine the amount of molding fluid injected into the mold plenum. 4. The method of claim 3, further including controlling the flow in response to the at least one parameter. 5. The method of claim 4, wherein sensing at least one parameter further comprises sensing prevailing pressure at which the molding fluid is injected. 6. The method of claim 3 wherein, sensing the at least one parameter to determine the amount of molding fluid injected into the mold plenum further includes sensing prevailing pressure in one of the first and second chambers. 7. The method of claim 3 wherein, sensing at least one parameter further comprises detecting displacement of molding fluid between the first and second fluid filled mold sections. 8. The method of claim 1 further comprising heating the molding fluid prior to injecting the molding fluid into the mold plenum. 9. The method of claim 1 further comprising heating the gas backing to a gas temperature prior to injecting molding fluid into the mold plenum. 10. The method of claim 9 further comprising regulating and selectively modulating the gas temperature after injecting molding fluid into the mold plenum. 11. An injection molding apparatus comprising: (a) a first thin membrane coupled to a first rigid mold section to define a first gas pressure chamber; (b) a second thin membrane coupled to a second rigid mold section to define a second gas pressure chamber; (c) a mold plenum defined between opposingly positioned mold surfaces of the first and second thin membranes; (d) an injection sprue in fluid communication with the mold plenum for delivering molding fluid to the mold plenum; and (e) at least one sensor interconnected to one of the first mold section, the second mold section, and the mold plenum. 12. The apparatus of claim 11 wherein the sensor is arranged to detect a parameter indicative of an amount of molding fluid injected into the mold plenum. 13. The apparatus of claim 11 further including a pressure sensor positioned between a source of the molding fluid and the injection sprue to detect injection pressure. 14. The apparatus of claim 11 further including a heating unit positioned in thermal communication with a source of the molding fluid and the injection sprue. 15. The method of claim 11 further including a heating unit configured to heat a gas, the heating unit being in fluid communication with the first and second gas pressure chambers. | CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provision Application No. 60/538,992 filed on Jan. 23, 2004; which application is incorporated herein by reference. TECHNICAL FIELD This disclosure relates generally to the manufacture of injection-molded articles. More particularly, this disclosure relates to methods and apparatus for injection molding polymer and composite articles. BACKGROUND The present disclosure relates to the manufacture of injection molded articles. Such articles can be molded from a polymer thermoset resin or can be a composite, that is, can be made of a fiber reinforcement lattice within a cured resin matrix. More particularly, the present disclosure relates to a method and apparatus for injection molding such polymer and composite articles. Reaction injection molding and resin transfer molding are processes wherein dry fiber reinforcement plys (preforms) are loaded in a mold cavity having surfaces that define the ultimate configuration of an article. In such processes, a flowable resin is injected, or vacuumed, under pressure into the mold cavity (mold plenum) to produce the article, or to saturate/wet the fiber reinforcement preforms. After a period of curing, the finished article is removed from the mold plenum. What is needed in the industry is an injection molding apparatus that is easier and less costly to operate. In addition, it is desirable to improve article quality and shorten production cycle time offering increased temperature control during both endothermic and exothermic processes. SUMMARY In one aspect, the present disclosure relates to a method of molding an article including attaching first and second membranes to first and second rigid mold sections to define first and second chambers and a mold plenum between opposing surfaces of the first and second members. The method also includes filing and pressurizing the first and second chambers with a gas backing at a gas pressure level, injecting molding fluid into the mold plenum. The gas pressure within the mold plenum is monitored during the molding of the article. In another aspect, the present disclosure relates to an injection molding apparatus including a first thin membrane coupled to a first rigid mold section to define a first gas pressure chamber, and a second thin membrane coupled to a second rigid mold section to define a second gas pressure chamber. A mold plenum is defined between the first and second thin membranes. The apparatus further includes an injection sprue in fluid communication with the mold plenum and at least one sensor interconnected to the one of the first mold section, the second mold section, and the mold plenum, the sensor being configured to detect a parameter indicative of an amount of molding fluid injected into the mold plenum. A variety of examples of desirable apparatus features or methods are set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practicing various aspects of the disclosure. The aspects of the disclosure may relate to individual features as well as combinations of features. It is to be understood that both the foregoing general description and the following detailed description are explanatory only, and are not restrictive of the claimed invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially diagrammatic, partially exploded isometric view of an injection molding apparatus in accordance with the present disclosure. FIG. 2 is a cross-sectional view of the apparatus shown in FIG. 1, taken along line 2-2, subsequent to assembly of an upper mold section onto a lower mold section. FIG. 3 is a partially diagrammatic, partially exploded isometric view of another embodiment of an injection molding apparatus similar to FIG. 1, but further including devices for providing feedback during the molding process. FIG. 4 is an exploded perspective view of an embodiment of the apparatus in FIG. 1 used for molding boat hulls. FIG. 5 is a cross sectional view, similar to FIG. 2, of the apparatus embodiment shown in FIG. 4 subsequent to partial assembly. FIG. 6 is a simplified schematic of the apparatus shown in FIG. 4 illustrating the interchangeability of membranes. DETAILED DESCRIPTION Referring to FIG. 1, one embodiment of an apparatus 10 for molding a composite article is illustrated. The apparatus 10 includes a mold assembly 12 having an upper mold section 14 and a lower mold section 16. The upper mold section 14 is configured to couple with the lower mold section 16 to define a mold plenum 22 with matched molding surfaces 24, 26. The upper and lower mold sections 14, 16 can be coupled with the aid of locating pins 18 and complimentary pin receivers 20. The upper and lower mold sections 14, 16 each include a rigid housing 28, 30 and a semi-rigid membrane 32, 34. In one embodiment, the semi-rigid membrane 32, 34 is removably and sealably secured to the respective rigid housing 28, 30 along the membrane's peripheral edge by a flange 36. The flange 36 can have an inner periphery having a geometry which corresponds to the geometry of the semi-rigid membrane 32, 34 and an outer periphery having a geometry corresponding to the geometry of the housing 28, 30. In a preferred embodiment, the flange 36 is reusable so that when a semi-rigid membrane 32, 34 is replaced, the flange 36 can be detached from the old membrane and attached to a new membrane. Once assembled, the housings 28, 30 and membranes 32, 34 of each mold section 14, 16 cooperate to define gas-tight chambers 38, 40 (FIG. 2). In accordance with one feature of the present disclosure, each membrane 32, 34 is preferably a thin-skin configuration and formed of a composite overlay. The thin-skin configuration of the membrane is preferably of a thickness that reduces the overall weight of the apparatus as compared to conventional molding equipment. Further, as will be discussed in greater detail, the thin-skin configuration is also configured to reduce cycle time by increasing the rate of thermal communication during endothermic and exothermic processes. The semi-rigid membranes 32, 34 may be formed of fiber reinforced plastics, although other suitable materials such as light sheet metal, may also be used. In this regard, it is noted that the use of either the same or different materials for the respective membranes 32, 34 of each mold section 14, 16 is contemplated depending upon, for example, the desired characteristics of the membranes (e.g., its thermal conductivity, formability, and usable life), the desired characteristics of the fabricated article (e.g., surface finish and gloss), and/or overall process parameters (e.g., resin injection pressures, resin cure time and mold assembly cycle time). In one embodiment, each of the thin-skin, semi-rigid membrane 32, 34 has an overall thickness T1, although the disclosed principles can be applied in a variety of thicknesses and applications. The thickness T1 of the thin-skin membranes is generally defined as the average wall thickness T1 along a central region of each sidewall 33, 35 and bottom wall 37, 39, and is preferably between 0.3 and 1.0 cm (0.100 and 0.400 inches). In some applications, it may be desirable to have thin-skin membranes of different thickness rather than thin-skin membranes having the same average wall thickness T1 as illustrated. In use, each mold section 14, 16 is filled with a backing gas 42 supplied by a gas supply network 44 (FIG. 1). When the mold sections 14, 16 are adequately filed, the gas 42 supports each membrane 32, 34 in compression during resin injection in a manner to be further described below. In the embodiment shown in FIG. 2, the membrane backing gas 42 is supplied by the network 44 (FIG. 2) to the upper and lower mold sections 14, 16 through respective inlet control valves 46 and quick connect couplings 48. A pressure gauge 50 may be positioned downstream of each inlet valve 46 to monitor the flow rate of backing gas 42 into the chamber 38, 40 of each mold section 14, 16. To facilitate the discharge of backing gas 42 from the chambers 38, 40, each mold section 14, 16 can have a vent 52 through which the backing gas 42 may be exhausted. A vent valve 54 seals the chamber's vent 52 when pressurization is required. The vent valve 54 may include a pressure relief arrangement to reduce or limit undesired pressure build up within the chambers 38, 40 and control discharge of the backing gas 42 from the mold sections 14, 16. As shown in FIG. 2, wherein the relative dimensions of, for example, the membranes 32, 34 and mold plenum 22 are exaggerated for ease of illustration, each mold section 14, 16 is provided with a system of heating/cooling coils 56 extending within the gas-tight chambers 38, 40 for regulating the temperature of the mold plenum 22. The optional heating/cooling coils 56 can be coupled via quick connect couplings 58 to an external heater 60 and chiller 61 (FIG. 1) units of conventional design. As such, the coils 56 operate in conjunction with the heater 60 and chiller 61 units to precisely regulate the temperature of the backing gas 42 and, hence, the molding surface 24, 26 of each membrane 32, 34 during the injection molding process. The thermal conductivity of the backing gas 42 enables substantial design variation with respect to placement of the coils 56 within each mold section 14, 16. This, in turn, permits use of a given mold section 14, 16 and coil system 56 with a wide variety of membrane 32, 34 configurations. In the some applications, the backing gas 42 is supplied at a temperature different from the desired process temperature. The vent 52 of the apparatus 10 through which the backing gas 42 is exhausted may be used to accommodate the varying temperature and pressure changes during manufacturing process. Thus, during heating or cooling of each mold section 14, 16 to the desired temperature, any resulting thermal expansion of the backing gas 42 within the chambers 38, 40 is accommodated by a pressure relief valve, for example, of the vent 52 to prevent distortion and/or deleterious stress on the membranes 32, 34. In an alternative embodiment, a pressure relief valve or arrangement (not shown) may be located prior to the coupling 48 of the apparatus 10, or anywhere along the apparatus where thermal expansion of the backing gas 42 can be controlled. Preferably, the apparatus 10 includes a controller 62 (FIG. 1) that monitors and/or regulates the pressure of the backing gas 42. For example, a compressor (not shown), the control valve 46, the pressure gauge 50, and the chamber vent 52 may all be interconnected to the controller 62 and operated according to a particular manufacturing procedure, for example. Various sensors may be used to provide feedback for monitoring and regulating the pressure of the backing gas 42; the sensors being in communication with the controller 62. Such sensors can include, for example, pressure gauges located at various points in the system and chambers, strain gauges, or other sensors/gauges that provide feedback information related to the backing gas pressure. The controller can be used to precisely control and vary the pressure of the backing gas 42 within the chambers 38, 40. A preferred manufacturing cycle may include changing the backing gas pressure within the chambers 38, 40 at predetermined times during the manufacturing cycle. The pressures may range between 2 psi and 10 psi, for example, during a manufacturing cycle. In one embodiment, the controller 62 is programmed to automatically monitor and regulate the manufacturing cycle in accord with predetermined pressure values. Likewise, sensors, and components such as the heater/chiller units 60, 61, can also be interconnected to the controller 62 for monitoring and regulation of the backing gas temperature. As shown in FIG. 2, an injection sprue 64 extends through the upper mold section 14 to provide a pathway through which a desired thermoset resin from a molding fluid supply 66 (FIG. 1) may be injected. The resin is injected in the mold plenum 22 under pressure by a injection pump 68. The number and placement of such sprues 64 can vary depending upon the configuration and desired characteristics of the article to be molded and the flow characteristics of the molding fluid employed. A series of small vents 70 (FIG. 1) is provided between the opposed flanges 36 of the upper and lower mold sections 14, 16 to blend trapped air from the mold plenum 22 to the atmosphere during injection of the molding fluid into the mold plenum 22. Other conventional methods of bleeding trapped air from the mold plenum 22 may be used. In accordance with another feature of the present disclosure, the molding apparatus 10 can further include a mechanism indicated generally by reference numeral 72 (FIG. 1) for vibrating the mold assembly 12. Vibration of the mold assembly 12 during injection of the resin can facilitate resin flow through the mold plenum 22, and may also improve saturation and wetting of any fiber reinforcement preforms situated within the mold plenum. The mechanism 72 can be positioned on the lower mold section 16 as illustrated, or the upper mold section 14. In use, one or more fiber reinforcement preforms are laid within the mold cavity defined by the “female” molding surface 26 of the lower mold section 16. The upper mold section 14 is then lowered onto the lower mold section 16 to engage locational alignment hardware on each mold section 14, 16, such as locating pins 18 and respective pin receivers 20. If desired, the upper mold section 14 can then be secured to the lower mold section 16 by use of suitable clamps (not shown). Each mold section 14, 16 is then connected to the backing fluid supply network 44 and the inlet valve 46 is operated to adequately fill the chamber 38,40 with backing gas before injection molding of the articles begins. During manufacture of a number of articles, the mold sections 14, 16 may be filled with the backing gas 42 only once prior to beginning the injection process. It is not necessary to fill each mold section 14, 16 after removing the molded article to then refill the sections before molding additional articles. As can be understood, by using the backing gas 42, the apparatus 10 is significantly lighter than an apparatus having a backing liquid, for example. This permits an operator to more easily transport or manipulate the mold sections 14, 16 of the present apparatus 10. In addition, by using backing gas 42, the chambers fill more quickly and evenly than an apparatus that uses backing liquid. This increases production cycle time and manufacturing efficiency. Once the chambers 38, 40 are adequately filled with the backing gas 42, the controller 62 and the heater 60 and chiller 61 units are operated to bring each mold section 14, 16 to the desired process temperature and pressure. When the desired process temperature and pressure are reached, an amount of molding fluid is injected into the mold plenum 22. Injecting a proper amount of molding fluid can be visually confirmed by discharge of the molding fluid through air bleeds formed in the flanges 36 of each mold section 14, 16. In the alternative, sensors can be used to determine the proper injection amount. The use of feedback from different types of sensors to optimize the molding process is discussed below in more detail. The temperature of each molding surface 24, 26 can be regulated via operation of the heater 60 and chiller 61 units to thereby provide an optimum cure rate with which to obtain the desired surface finish and/or other desired characteristics of the finished article, or to otherwise optimize the molding process. The mold sections 14, 16 are thereafter separated, and the finished article can be removed from the mold cavity manually or using automatic injectors. In accordance with another feature of the present invention, due to the thin-skin configuration of the membranes 32, 34, the membranes can dimensionally flex slightly during the injection of molding fluid as the backing gas 42 distributes the resulting injection pressure load across the entire surface of the membranes 32, 34. In this manner, the thin-skin membranes 32, 34 avoid deleterious stress concentrations on the molding surfaces 24, 26 during injection. Further, the flexing of the molding surfaces 24,26 of one or both membranes 32, 34 during injection is believed to further improve or enhance the flow of molding fluid through the mold plenum 22, which effect may be enhanced by deliberately pulsing the injected molding fluid, or altering the backing gas pressure within the chambers, all without deleterious impact on the molding tools (i.e. the membranes 32, 34). To optimize the molding process, various devices can be employed to provide feedback that can be utilized to adjust different parameters of the molding process, such as injection rate, to improve the quality of the molded article. A second exemplary molding apparatus 100 is shown in FIG. 3, having a mold assembly 112 with mold sections 114, 116 similar to the molding apparatus 10 shown in FIG. 1. As shown, molding fluid can be delivered from a molding fluid storage container 166 by an injection pump 168. The system can also preferably include a resin heater 170, flowmeter 172, pressure sensor 174 and mixing head 176 between the pump 168 and the injection sprue 164. The molding apparatus 110 can also include certain preferred devices for providing feedback to optimize the molding process. Both internal and external devices can be employed to provide feedback for use in monitoring and optimizing the molding process while injection is ongoing. Sensors internal to the mold can include, for example, temperature sensors 191 which can be provided at multiple locations in each mold section 114, 116 to monitor the temperature in the mold plenum 122. The temperature sensors can be devices well known to those of skill in the art, such as RTDs and thermocouples. Other internal feedback systems can include pressure transducers 195 within the mold sections 114, 116 and passive sensors 198 (FIG. 5) within the mold plenum 122 itself for detecting the progress of the molding fluid as it fills the mold plenum 122. These passive sensors 198 are shown, in FIG. 5, as positioned, for example, on the male mold membrane 200. However, the passive sensors 198 could also be located on the female mold membrane 203 or on both membranes. The pressure transducers 195, sense the pressure in the mold sections 114, 116 while molding fluid is being injected into the mold plenum 122 and provide feedback indicative of the pressure in the mold plenum 122. As the plenum 122 is filling with molding fluid, pressure sensed in the mold section 114, 116 will typically gradually increase. However, as the mold plenum 122 becomes substantially filled, the pressure sensed will generally increase relatively sharply. The relatively sharp increase in pressure indicates that the plenum 122 is substantially full and the injection process can be regulated accordingly. Additionally, pressure sensors could be provided to sense pressure associated with mold plenum itself by, for example, providing sensors on the one or both of the mold membranes 200, 203. The passive sensors 198 can be arranged to detect the leading edge of the molding fluid as it fills the mold plenum 122. Such passive sensors 198 can be passive proximity switches. These switches are designed to detect the leading edge of the flow without impeding that flow through the mold plenum 122. The passive proximity switches can be of the types well known to those skilled in the art, a preferred type being, for example, a capacitive proximity switch. Additionally, external devices can also be provided for sensing various other parameters during the injection process. For example, linear velocity/displacement transducers (LVDTs) can be provided to detect when all or a part of the mold plenum has filled. The LVDTs detect displacement between the two mold sections 114, 116 when molding fluid is being injected into the mold plenum 122. The amount of displacement is indicative of whether, and how much, the mold plenum has filled. Such LVDTs as utilized herein are well known to those of ordinary skill in the art. The flow meter 172 can be employed to monitor the flow rate of the molding fluid as is being injected. Moreover, the pressure gauge 174 can be provided to measure the pressure at which the molding fluid is being injected. If the injection pressure falls outside of a desired range of pressure, the injection rate can be adjusted accordingly. Another device for optimizing the molding process is the molding fluid heating unit 170 which can be used to heat the molding fluid. Heating the molding fluid can alter its viscosity and thus change the flow rate. As shown in FIG. 3, the heating unit 170 can preferably be positioned in the system between the injection pump 168 and the flowmeter 172 so that the change in flow rate caused by the heater 170 can be monitored. Feedback from all of the aforementioned internal and external devices can be advantageously utilized to optimize the molding process even as the molding fluid is being injected. Together, the sensors form a response system which is designed to close the loop between CNC injection machinery and the floating mold. This response system, in conjunction with controller 62, for example, permits injection profiles to be adjusted dynamically based on actual mold conditions and parameters in order to optimize the injection process even as the mold plenum 122 is being filled with molding fluid. This ability to dynamically control and optimize the molding process also contributes to reduced cycle time and improved cosmetics of the molded part as well as reduced wear on tooling. The hollow gas filled mold sections 14, 16, 114, 116 provide excellent thermal conductivity which permits superior mold temperature control. The controlled temperature ranges permit the rheology to be much faster in cycle times and provides the added bonus of the chemical reaction's optimal control limits being unaffected by ambient temperature ranges that can otherwise effect production rates. In construction of a molding apparatus according to the invention, and as described above in connection with FIGS. 1-3, a master model can be used to create a pair of molding surfaces. As shown in FIGS. 4 through 6, one male mold membrane 200 and one female mold membrane 203 are produced to create the proper cavity size therebetween. Preferably, the sprue 164, sensors and any other hardware which must communicate through the mold membranes 200, 203 into the plenum 122 can be releasably connected using modular bulkhead fittings, such as the sprue bulkhead fitting 235 (FIG. 5) and passive proximity switch bulkheads 245. The modular bulkhead fittings 235, 245 can be adapted to releasably connect the requisite molding hardware and sensors to the mold membranes 200, 203. In this manner, all of the necessary closed molding hardware and sensors can be quickly connected or removed from the mold skins 200, 203. The molding hardware and sensors can include, for example, sprues, automatic ejectors, and various sensors such as thermocouples and proximity switches. Consequently, it is not necessary to laminate each individual piece of hardware and sensor directly into the mold membrane. Instead, all hardware is releasably connected to the modular fittings 235, 245 for convenience and efficiency of changing out the molds. When the membranes 200, 203 are changed out, the quick connected hardware is simply disconnected form the changed out membranes 200, 203 and reconnected to modular fittings 235, 245 provided on the replacement mold membranes 224, 227 (FIG. 6). However, these components could be alternatively laminated molded directly into the mold membrane 200, 203 itself. To construct the two mold halves, a pair of universal vessels 209, 212 are be created, one for the male membrane 200 and one for the female membrane 203. The framework of each universal vessel 209, 212, is provided with an outer skin 210, 213 (FIG. 5) which can be made from, for example, sheet metal, to form a rigid enclosed mold section 114, 116. Flanges 215 can be attached to each of the mold membranes 200, 203. Each mold membrane 200, 203 is attached to its own corresponding universal vessel 209, 212 via the flanges 215 to create a gas-tight seal between each universal vessels and its corresponding mold membrane. A single mold 112 comprised of two mold sections 114, 116 with attached mold membranes 200, 203 can be utilized to produce a variety of different parts simply by changing out the male 200 and female 203 mold membranes attached to each universal vessel 209, 212. Although not shown in FIG. 4, each mold section 114, 116 can also be provided with the heating coils 56 described in connection with FIG. 2. The optional heating coils 56 can likewise be connected to the heater 160 and chiller 161 units for controlling the temperature of the backing gas 42. Because each mold sections 114, 116 is gas filled, the mold has excellent thermal conductivity which allows for much improved temperature control of the mold surfaces which results in reduced cycle time and improved cosmetics. As shown in FIG. 6, molding differently configured parts is as simple as removing one set of mold membranes 200, 203 and replacing them with a differently configured set 227, 224. Some benefits of the floating mold are flexibility, reduced cost, speed to market and increased closed molding performance. For example, when a part design is changed, rather than creating new molds and obsoleting current molds, or performing expensive mold modifications, the molded membranes are simply changed out. As shown in FIGS. 4-6, a good example of an application for the floating mold is the molding of boat decks and hulls. The molder can easily change out the membranes 200, 203 of the mold sections 114, 116 to create different parts whenever needed. The floating molds are designed to allow the entire mold to be changed out in less than ten minutes. Because of the thin-skin configuration of the membranes, heat transfer control of the molded part is enhanced and the mold membranes can be formed more easily and less expensively. Preferably, each mold membrane can be formed from a highly thermally-conductive material. While certain preferred embodiments of the invention have been disclosed and described herein, it should be appreciated that the invention is susceptible of modification without departing from the spirit of the invention or the scope of the following claims. | <SOH> BACKGROUND <EOH>The present disclosure relates to the manufacture of injection molded articles. Such articles can be molded from a polymer thermoset resin or can be a composite, that is, can be made of a fiber reinforcement lattice within a cured resin matrix. More particularly, the present disclosure relates to a method and apparatus for injection molding such polymer and composite articles. Reaction injection molding and resin transfer molding are processes wherein dry fiber reinforcement plys (preforms) are loaded in a mold cavity having surfaces that define the ultimate configuration of an article. In such processes, a flowable resin is injected, or vacuumed, under pressure into the mold cavity (mold plenum) to produce the article, or to saturate/wet the fiber reinforcement preforms. After a period of curing, the finished article is removed from the mold plenum. What is needed in the industry is an injection molding apparatus that is easier and less costly to operate. In addition, it is desirable to improve article quality and shorten production cycle time offering increased temperature control during both endothermic and exothermic processes. | <SOH> SUMMARY <EOH>In one aspect, the present disclosure relates to a method of molding an article including attaching first and second membranes to first and second rigid mold sections to define first and second chambers and a mold plenum between opposing surfaces of the first and second members. The method also includes filing and pressurizing the first and second chambers with a gas backing at a gas pressure level, injecting molding fluid into the mold plenum. The gas pressure within the mold plenum is monitored during the molding of the article. In another aspect, the present disclosure relates to an injection molding apparatus including a first thin membrane coupled to a first rigid mold section to define a first gas pressure chamber, and a second thin membrane coupled to a second rigid mold section to define a second gas pressure chamber. A mold plenum is defined between the first and second thin membranes. The apparatus further includes an injection sprue in fluid communication with the mold plenum and at least one sensor interconnected to the one of the first mold section, the second mold section, and the mold plenum, the sensor being configured to detect a parameter indicative of an amount of molding fluid injected into the mold plenum. A variety of examples of desirable apparatus features or methods are set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practicing various aspects of the disclosure. The aspects of the disclosure may relate to individual features as well as combinations of features. It is to be understood that both the foregoing general description and the following detailed description are explanatory only, and are not restrictive of the claimed invention. | 20050119 | 20090630 | 20050825 | 94155.0 | 0 | HUSON, MONICA ANNE | METHOD AND APPARATUS FOR MOLDING COMPOSITE ARTICLES | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,039,375 | ACCEPTED | Light shades and lighting systems | Light shades and lighting systems that create a spectral effect when a lighting element is illuminated within the shade, and features that reflect light originating within the shade. Embodiments of the invention incorporate hollow body having a diffraction grating thereon and an internal cavity to retain one or more lighting elements, and in some instances, to also retain one or more lengths of conductor. | 1. A shade for use with at least one lighting element, the shade comprising: a body having an internal cavity large enough for at least one lighting element to be positioned therein, at least a portion of the body being configured to allow light from inside the body to escape therefrom, at least a portion of the body having features thereon for breaking up light to create a spectral effect, and the body having an opening therein configured to allow a conductor to be routed to the at least one lighting element when the at least one lighting element is positioned in the internal cavity. 2. The shade of claim 1 wherein a first portion of the body has a reflective finish configured to reflect light originating within the body back into the body, and the features for breaking up light are located on a second portion of the body. 3. The shade of claim 2 wherein the reflective finish is located on a sheet of material affixed to an external surface of the body. 4. The shade of claim 1 wherein a first portion of the body has a reflective finish, and the features for breaking up light are located on a second portion of the body. 5. The shade of claim 1 wherein at least some of the features for breaking up light are located on a sheet of material affixed to a surface of the body. 6. The shade of claim 1 wherein the body comprises a pair of complementary portions adjoined by a hinging means. 7. The shade of claim 1 wherein the body is an assembly of a plurality of parts. 8. The shade of claim 1 wherein the body is an assembly of two complementary parts. 9. The shade of claim 1 wherein the body is an assembly of two complementary parts, at least one of the parts being formed in three dimensions. 10. The shade of claim 1 wherein the body comprises similarly-shaped parts with at least one frame member positioned between them. 11. The shade of claim 1 wherein the portion of the body configured to allow light to escape from the body comprises a translucent sheet of material. 12. The shade of claim 11 wherein the translucent sheet of material is transparent. 13. The shade of claim 1 wherein the portion of the body configured to allow light to escape from the body comprises a translucent sheet of material having light-refracting features thereon. 14. The shade of claim 1 wherein the cavity is large enough to hold a plurality of lighting elements and a conductor connecting the lighting elements together. 15. A lighting device comprising: at least one lighting element; a conductor configured to couple the at least one lighting element to a source of electricity; and a light shade having a body with an internal cavity within which at least one lighting element is positioned, at least a portion of the body being configured to allow light from inside the body to escape therefrom, at least a portion of the body having features thereon for breaking up light to create a spectral effect, and the body having an opening therein configured to allow the conductor to be routed to the at least one lighting element in the internal cavity. 16. The lighting device of claim 15 wherein a plurality of lighting elements and lengths of conductor are located within the cavity in the body. 17. A light string comprising: a plurality of lighting elements; a conductor electrically coupling the lighting elements together and configured to couple the lighting elements to a source of electricity; and a plurality of shades positioned at different locations along a length of the conductor, each of the shades comprising a body having an internal cavity within which at least one of the lighting elements is positioned, at least a portion of the body being configured to allow light from inside the body to escape therefrom, at least a portion of the body having features thereon for breaking up light to create a spectral effect, and the body having an opening therein configured to allow the at least one lighting element to be positioned within the body. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electric light shades, lighting displays and lighting systems. 2. Description of the Related Art Many different designs of ornaments and lighted displays have been developed to help people decorate their houses and yards during particular holidays. BRIEF SUMMARY OF THE INVENTION The present invention is directed toward light shades and strings of lights. In one disclosed embodiment, the invention is directed toward a shade for use with at least one lighting element. The shade has a hollow body with an internal cavity large enough for at least one lighting element to be positioned therein; at least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow a conductor to be routed to the at least one lighting element when the at least one lighting element is positioned in the internal cavity. In another disclosed embodiment, the invention is directed toward a light having at least one lighting element, a conductor for coupling the lighting element to a source of electricity, and a hollow body having an internal cavity within which at least one lighting element is positioned. At least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow the conductor to be routed to the at least one lighting element in the internal cavity. In another disclosed embodiment, the invention is directed toward a light string having lighting elements, a conductor, and light shades. The conductor electrically couples the lighting elements together and is configured to couple the lighting elements to a source of electricity. The light shades are positioned at different locations along the length of the conductor. Each of the light shades has a hollow body with an internal cavity within which at least one of the lighting elements is positioned. At least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow the at least one lighting element to be positioned within the hollow body. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) In order to assist understanding of the present invention, embodiments will now be described, purely by way of non-limiting example, with reference to the attached drawings, in which: FIG. 1 is an isometric view of a light shade according to an embodiment of the present invention; FIG. 2 is a plan view of the light shade of FIG. 1; FIG. 3 is a side view of the light shade of FIG. 1; FIG. 4 is plan view of an unassembled light shade according to an embodiment of the present invention; FIG. 5 is a side view of the unassembled light shade of FIG. 4; FIG. 6 is an isometric view of a light according to another embodiment of the present invention; FIG. 7a is an enlarged isometric view of a portion of a light according to an embodiment of the present invention; FIG. 7b is an enlarged isometric view of a portion of a light according to another embodiment of the present invention; FIG. 8 is an isometric view of a light string according to an embodiment of the present invention; FIG. 9 is a flow chart illustrating a method for manufacturing a light shade according to an embodiment of the invention; FIG. 10 is a flow chart illustrating a method for manufacturing a light and a light string according to an embodiment of the present invention; FIG. 11 is an isometric view of a light according to another embodiment of the invention; FIG. 12 is an isometric view of a light shade according to another embodiment of the present invention; FIG. 13A is an isometric view of a light display according to yet another embodiment of the present invention; FIGS. 13B and 13C are enlarged views of portions of the light display of FIG. 13A; FIG. 14 is an exploded isometric view of the light display of FIG. 13A; and FIG. 15 is a cross-section of a portion of the light display of FIG. 13A, viewed along Section 15-15. DETAILED DESCRIPTION OF THE INVENTION The present invention is directed toward devices and systems for use in decorating a home or yard during a holiday or other event. The following is a detailed description of a few illustrative embodiments. The drawings are provided to clarify the description, and may not be to scale. FIGS. 1-5 illustrate a light shade 20 according to one disclosed embodiment of the present invention. The illustrated light shade 20 is star shaped, having four arms 22 each terminating in a point 24. As shown in FIG. 3, the illustrated light shade 20 is bilaterally symmetrical about a plane of symmetry 26, such that a front surface 28 of the light shade 20 is at least substantially identical to a back surface 30. Many different shapes could be used instead of a star shape without deviating from the spirit of the invention; and the front and back surfaces 28,30 need not by symmetrical. In certain embodiments, one of the front and back surfaces 28,30 is flat. The front and back surfaces 28,30 of the illustrated embodiment are made from thin sheet material formed in three dimensions to create the shape of a faceted star. Accordingly, the contoured shape of the light shade 20 creates a corresponding internal cavity. The inventor appreciates that the hollow light shade 20 can be made through other means, such as by blow molding or other suitable means, without deviating from the spirit of the invention. As best illustrated in FIGS. 4 and 5, this particular light shade 20 is fabricated through a particular method. The front and back surfaces 28,30 are connected by a hinge 32, such as the living hinge illustrated in FIG. 4, which allows the surfaces to be rotated with respect to each other between an operating configuration, illustrated in FIGS. 1-3, and a non-operating configuration, illustrated in FIGS. 4 and 5. The non-operating configuration can be useful when, for example, assembling, storing, and/or transporting the light shade 20. The living hinge 32 can have perforations 34 or other features to facilitate correctly bending the front and back surfaces 28,30 to form the light shade 20. The inventor notes that the light shade 20 can be assembled through other means; and an individual of ordinary skill in the art having reviewed this disclosure will appreciate other means for assembling such a shade. As illustrated in FIG. 6, the light shade 20 can be configured to hold one or more lighting elements therein, such as the illustrated light bulbs 32. Where several light bulbs 32 are retained within the body of the light shade 20, the cavity can also be configured to retain the corresponding sockets 34 and lengths of conductor 36. The conductor 36 enters the light shade 20 through an opening 38. In certain embodiments, as discussed below, the conductor 36 can also exit the light shade 20. The material of the light shade 20 can be, as indicated above, formed from a thin sheet. In particular embodiments, the thin sheet is a translucent-and in some instances, a transparent-polymer treated to break light leaving the light shade 20 into some of its spectral elements. For example, the sheet can have a diffraction grating printed or otherwise formed thereon to diffract the light into various wavelengths, giving the light shade 20 a colorful, rainbow-like effect. Such treatment can cover select portions of the light shade 20 or can cover the entire light shade. As a result, the light originating with each of the light bulbs 32 passes through the skin of the light shade 20, breaking up into a spectral pattern and dispersing, giving the light shade a brilliant effect. Further, where the light display incorporates several light bulbs 32, such as that illustrated in FIG. 6, the display creates an even more brilliant effect when illuminated, as each light bulb creates its own spectral pattern. FIGS. 7A and 7B illustrate two possible variations that can be made to the present invention. The embodiment illustrated in FIG. 7A incorporates two openings 38, which allow the conductor 36 to both enter and leave the light display 20 through separate holes. This embodiment may be useful, for example, where the light display is one of a string of displays; the conductor 36 leaving the light shade 20 can be routed to the previous or next light display in the string, or to a connector for coupling the light string to another string. The embodiment illustrated in FIG. 7B incorporates one opening 38 located at the extreme distal end of the point 24 on one of the arms 22. This particular embodiment may be useful, for example, where the light display is suspended by the conductor 36; the light shade 20 hanging vertically below the conductor due to the force of gravity. In other embodiments, the light display can be suspended from hooks, loops or other known hardware suitable for such purposes. FIG. 8 illustrates a light string 40 having a number of light displays along the length of the conductor 36. The light displays in the illustrated embodiment incorporate light shades 20 according one of the embodiments of the present invention. The light string 40 can be modified to incorporate light shades 20 according to any of the embodiments disclosed herein, as well as any known light shades, in any desired combination. FIG. 9 illustrates a method for making a light shade according to one particular embodiment of the present invention. In the disclosed embodiment, a translucent sheet is initially presented 42, having a diffraction grating or similar features thereon. The sheet is formed 44 to create a depression therein and, typically, to create a desired external shape. The formed sheet is then assembled 46 with one or more other sheets to form a light shade having a cavity therein. The other sheet or sheets can be flat or formed, and in instances such as those illustrated above, can be formed identical or similar to the first formed sheet. A light shade having one flat side may be more suitable than the other display for use against a wall or other flat surface, while the symmetrical style may be more desirable for being suspended in mid-air. FIG. 10 illustrates a method for making a light display and, if desired, a string of lights, according to a particular embodiment of the present invention. In the disclosed embodiment, a translucent sheet is presented 48. A diffraction grating is applied 50 to the translucent sheet. The diffraction grating can be applied directly to the transparent sheet, or can be applied to a separate sheet which is, subsequently, affixed to the translucent sheet. The separate sheet can itself be translucent, but could instead be opaque and, in some instances, reflective. The translucent sheet is formed 52 into a desired shape. In some embodiments, the translucent sheet may be formed 52 after the diffraction grating is applied 50 to the sheet; however, in other embodiments, the diffraction grating may be applied to the sheet after it has been formed. After the sheet has been formed 52, lights are enclosed 54 within a light shade made using the formed translucent sheet. After the light shade has been made, several light strings may be added 56 to the string. An individual of ordinary skill in the art, having reviewed this disclosure, will appreciate that the steps in the above methods can be exchanged in some instances, and/or can be combined in different sequences or without all of the other steps, to make other suitable light shades, light displays or light strings, without deviating from the spirit of the present invention. FIG. 11 illustrates another possible configuration of a light shade 120 according to the present invention. In the illustrated embodiment, a single light bulb 32 is positioned within a cavity in the light shade 120. The opening 38 in the light shade 120 receives the socket 34, and the conductor 36 passes to and from the socket without entering the light shade. FIG. 12 illustrates a configuration of a light display incorporating a light shade 220 according to still another possible embodiment of the present invention. In the illustrated embodiment, a front surface 228 similar to that illustrated and described in the first embodiment herein, is mounted to a frame 221, which can have an outer perimeter similar to an outer perimeter of the front surface. The front surface 228 can be glued to the frame 221, or can be affixed to the frame by any suitable means. The frame 221 can extend throughout portions of the light shade 220, and the sockets 34 for the light bulbs 32 can be attached to the frame at various places using known means. The conductor 36 is routed to the light sockets 34, and can enter and, if desired, leave the light shade 220 as discussed above. The front surface 228 can have different portions, each portion affecting light in a different way. A first portion 223 of the front surface can be adapted to allow light to escape the light shade 220. The first portion 223 could include holes and/or translucent material (again, a term intended herein to incorporate transparent materials), and can be a material similar to that discussed in connection with the first embodiment, above. That is, the first portion 223 can incorporate a diffraction grating, either directly or through affixation, to break light leaving the light shade 220 into its spectral elements. In situations where the diffraction grating is affixed to the front surface 228 of the first portion 223, the inventor appreciates that the diffraction grating can be printed or otherwise applied to a strip of material that is then either applied smoothly over the surface or at angles to the surface to provide the light shade 220 with an even more brilliant effect. The second portion 225 of the front surface 228 can be adapted to reflect light, externally and/or internally with respect to the light display. In addition, the second portion 225 can be adapted to refract light into some of its spectral elements, further increasing the brilliant effect of the light display. The second portion 225 can be covered with a metallic foil or with a paper that is itself covered with metallic foil, and/or can be printed or otherwise treated to create a diffraction grating over the reflective foil, thus both reflecting and breaking up light. The paper or foil can be smoothly affixed to the second portion 225 of the front surface 228, or can be bent, wrinkled or otherwise angled with respect to the surface to further break up the light and create a more brilliant effect. In the illustrated embodiment, the front surface 228 is faceted such that the several first portions 223 of the front surface face the several second portions 225. As a result, light escaping the light shade 220 through the first portions 223 is directed, at least in part, toward the second portions 225. The light impinging the second portions 225 of the front surface 228 is then refracted, creating several spectral effects. Thus, even though half of the front surface 228 in the illustrated embodiment is opaque, all of the front surface can create spectral light, making the entire lighted display 220 brilliant. FIGS. 13-15 illustrate a light display incorporating a light shade 320 according to still another embodiment of the present invention. In the illustrated embodiment, a frame 321 similar in structure to that disclosed above and illustrated in the corresponding drawings, is interposed between a front surface 328 and a back surface 330. A conductor 36 and several light bulbs 32 and sockets 34 are positioned within an internal cavity delimited by the frame 321 and the front and back surfaces 328,330. The illustrated front surface 328 is a flat, translucent sheet of material, such as a polymer or resin-based material, having indicia thereon to create a desired decorative effect. A first portion 323 of the front surface 328 can be translucent and can be treated or covered with light-diffracting features such as those disclosed above in connection with the first surface 223 in a previous embodiment. A second portion 325 of the front surface 328 can be colored, opaque and/or treated to diffract and/or reflect light, such as that discussed above in connection with the second portion 225 in a previous embodiment. The first and second portions can be randomly selected or can be selected to create a desired image, such as the present shown in the figures. The inventor intends this image to be merely an example, and appreciates that any other desired design could be used instead. The back surface 330 can be similar to the front surface 328 or can be a simple sheet of material, translucent or opaque, depending on the desired use of the display. In addition, the interior of the back surface 330 can be reflective to direct additional light toward-and through-the front surface 328. The back surface 330 could also be formed and contoured similar to one of the surfaces described in the first embodiment, above, to give the display two distinct designs, depending on the direction the display is facing. One of ordinary skill in the art, having reviewed this disclosure, will appreciate these and other variations and modifications that can be made to the disclosed embodiments without deviating from the spirit of the invention. As illustrated in FIGS. 13B and 13C, the first portion 323 of the front surface 328 can have deposits 331 thereon, which can be dispersed across the first portion in a pattern, array, or other distribution. The deposits 331 can be small enough not to distract an individual viewing the light display, while being large enough to reflect, refract and/or diffract light that impinges the deposit. In the illustrated embodiment, the deposits 331 are made with a material having reflective properties, and have a diffraction grating 333 thereon so that light impinging the deposits from outside the light display is reflected and diffracted, creating a brilliant spectral effect. Between the deposits 331, the first portion 323 of the front surface 328 can be translucent, allowing light to escape the light shade 320. As best illustrated in FIGS. 14 and 15, the disclosed light display is assembled such that the front surface 328 and/or back surface 330 is spaced apart from the frame 321. In the illustrated embodiment, the front surface 328, frame 321 and back surface 330 are coupled together and spaced apart using a rivet-type fastener 335, a bushing 337, and a cap 339. The rivet-type fastener 335 passes through corresponding holes 341 in the front and back surfaces 328, 330. Between the front and back surfaces 328,330, both the rivet-type fastener 335 and the bushing 337, surrounding the rivet-type fastener, pass through a hole 343 in the frame 321. The cap 339 is fixed to a distal end of the rivet-type fastener 335 on the external side of the back surface 330. The inventor appreciates that many other means can be used to assemble and, if desired, space apart the front surface 328, the frame 321, and the back surface 330. From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to electric light shades, lighting displays and lighting systems. 2. Description of the Related Art Many different designs of ornaments and lighted displays have been developed to help people decorate their houses and yards during particular holidays. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>The present invention is directed toward light shades and strings of lights. In one disclosed embodiment, the invention is directed toward a shade for use with at least one lighting element. The shade has a hollow body with an internal cavity large enough for at least one lighting element to be positioned therein; at least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow a conductor to be routed to the at least one lighting element when the at least one lighting element is positioned in the internal cavity. In another disclosed embodiment, the invention is directed toward a light having at least one lighting element, a conductor for coupling the lighting element to a source of electricity, and a hollow body having an internal cavity within which at least one lighting element is positioned. At least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow the conductor to be routed to the at least one lighting element in the internal cavity. In another disclosed embodiment, the invention is directed toward a light string having lighting elements, a conductor, and light shades. The conductor electrically couples the lighting elements together and is configured to couple the lighting elements to a source of electricity. The light shades are positioned at different locations along the length of the conductor. Each of the light shades has a hollow body with an internal cavity within which at least one of the lighting elements is positioned. At least a portion of the hollow body is configured to allow light from inside the body to escape therefrom; at least a portion of the hollow body has features thereon for breaking up light to create a spectral effect; and the hollow body has an opening therein configured to allow the at least one lighting element to be positioned within the hollow body. | 20050119 | 20071204 | 20060720 | 99877.0 | F21V1100 | 1 | HAN, JASON | LIGHT SHADES AND LIGHTING SYSTEMS | UNDISCOUNTED | 0 | ACCEPTED | F21V | 2,005 |
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11,039,448 | ACCEPTED | Releasably locking hinge for an orthopedic brace having adjustable rotation limits | A hinge is provided for an orthopedic brace having a first rotation plate, a second rotation plate, a pivotal connector connecting the first and second rotation plates, a rotation limiting mechanism, and a rotation locking mechanism. The rotation limiting mechanism includes a rotation limiting face formed in the peripheral edge of the second rotation plate and a rotation limiting assembly selectively positionable in a fixed position relative to the first rotation plate. The rotation limiting assembly has a stop face engageable with the rotation limiting face upon rotation of the first and second rotation plates, which limits further rotation in a first rotation direction. The rotation locking mechanism includes a rotation lock pin and a series of lock notches formed in the peripheral edge of the second rotation plate. The rotation lock pin is selectively positionable within one of the series of lock notches, which substantially locks the first and second rotation plates against rotation in the first rotation direction or in a second rotation direction opposite the first. | 1. A hinge for an orthopedic brace comprising: a first rotation plate having a first peripheral edge, an inner face and an outer face; a second rotation plate having a second peripheral edge; a pivotal connector connecting said first and second rotation plates; a rotation limiting mechanism including, a series of rotation limiting teeth formed in said inner face at said first peripheral edge, a rotation limiting face formed in said second peripheral edge, and a rotation limiting assembly having an engagement face selectively positionable between two adjacent teeth of said series of said teeth to place said rotation limiting assembly in a fixed position and having a stop face engageable with said rotation limiting face upon rotation of said second rotation plate relative to said first rotation plate in a first rotation direction to substantially limit further rotation of said second rotation plate relative to said first rotation plate in said first rotation direction; and a rotation locking mechanism including, a series of lock notches formed in said second peripheral edge, a lock pin slot formed in said inner face, and a rotation lock pin slidably positioned in said lock pin slot and selectively positionable within one of said series of lock notches to substantially lock said first and second rotation plates against rotation of said second rotation plate relative to said first rotation plate in said first rotation direction or in a second rotation direction opposite said first rotation direction. 2. The hinge of claim 1 wherein said rotation limiting mechanism further includes a biasing member biasing said engagement face radially inward from said first peripheral edge. 3. The hinge of claim 1 wherein said rotation locking mechanism further includes a lock actuator assembly engaging said rotation lock pin, wherein said rotation lock pin has a longitudinal axis, said lock actuator assembly maintaining said longitudinal axis of said rotation lock pin substantially perpendicular to said inner face. 4. The hinge of claim 1 wherein said rotation locking mechanism further includes a lock actuator assembly engaging said rotation lock pin, wherein said rotation lock pin has a longitudinal axis and said lock pin slot has a longitudinal axis, said lock actuator assembly maintaining said longitudinal axis of said rotation lock pin substantially perpendicular to said longitudinal axis of said lock pin slot. 5. The hinge of claim 1 wherein said rotation locking mechanism further includes a lock transition plate and a lock actuator assembly engaging said rotation lock pin, wherein said lock transition plate has a lock assembly cut-out and said lock actuator assembly has an actuator bar selectively and slidably positioned in said lock assembly cut-out. 6. The hinge of claim 5 wherein said lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and said actuator bar has a protrusion configured for close fitting within said first depression and said second depression when said actuator bar is selectively slid within said lock assembly cut-out. 7. The hinge of claim 1 wherein said rotation lock pin is transitionable between a locked position, wherein said rotation lock pin is selectively positioned within said one of said series of lock notches, and an unlocked position, wherein said rotation lock pin is selectively withdrawn from said one of said series of lock notches, without substantially modifying said fixed position of said rotation limiting assembly. 8. A hinge for an orthopedic brace comprising: a first rotation plate having a first peripheral edge, an inner face and an outer face; a second rotation plate having a second peripheral edge; a pivotal connector connecting said first and second rotation plates; a rotation limiting mechanism including, a rotation limiting face formed in said second peripheral edge, and a rotation limiting assembly selectively positionable in a fixed position relative to said first rotation plate and having a stop face engageable with said rotation limiting face upon rotation of said second rotation plate relative to said first rotation plate in a first rotation direction to substantially limit further rotation of said second rotation plate relative to said first rotation plate in said first rotation direction; and a rotation locking mechanism including, a series of lock notches formed in said second peripheral edge, and a rotation lock pin selectively positionable within one of said series of lock notches to substantially lock said first and second rotation plates against rotation of said second rotation plate relative to said first rotation plate in said first rotation direction or in a second rotation direction opposite said first rotation direction. 9. The hinge of claim 8 wherein said rotation limiting mechanism further includes a biasing member biasing said engagement face radially inward from said first peripheral edge. 10. The hinge of claim 8 wherein said rotation locking mechanism further includes a lock actuator assembly engaging said rotation lock pin, wherein said rotation lock pin has a longitudinal axis, said lock actuator assembly maintaining said longitudinal axis of said rotation lock pin substantially perpendicular to said inner face. 11. The hinge of claim 8 wherein said rotation locking mechanism further includes a lock transition plate and a lock actuator assembly engaging said rotation lock pin, wherein said lock transition plate has a lock assembly cut-out and said lock actuator assembly has an actuator bar selectively and slidably positioned in said lock assembly cut-out. 12. The hinge of claim 11 wherein said lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and said actuator bar has a protrusion configured for close fitting within said first depression and said second depression when said actuator bar is selectively slid within said lock assembly cut-out. 13. The hinge of claim 8 wherein said rotation lock pin is transitionable between a locked position, wherein said rotation lock pin is selectively positioned within said one of said series of lock notches, and an unlocked position, wherein said rotation lock pin is selectively withdrawn from said one of said series of lock notches, without substantially modifying said fixed position of said rotation limiting assembly. 14. A rotation locking mechanism for a hinge of an orthopedic brace, said hinge having a first rotation plate with a first peripheral edge, an inner face and an outer face, a second rotation plate with a second peripheral edge, and a pivotal connector connecting said first and second rotation plates, said rotation locking mechanism comprising: a series of lock notches formed in said second peripheral edge; a lock pin slot formed in said inner face; and a rotation lock pin slidably positioned in said lock pin slot and selectively positionable within one of said series of lock notches to substantially lock said first and second rotation plates against rotation of said second rotation plate relative to said first rotation plate in a first rotation direction or in a second rotation direction opposite said first rotation direction. 15. The hinge of claim 14 wherein said rotation locking mechanism further comprises a lock actuator assembly engaging said rotation lock pin, wherein said rotation lock pin has a longitudinal axis, said lock actuator assembly maintaining said longitudinal axis of said rotation lock pin substantially perpendicular to said inner face. 16. The hinge of claim 14 wherein said rotation locking mechanism further includes a lock transition plate and a lock actuator assembly engaging said rotation lock pin, wherein said lock transition plate has a lock assembly cut-out and said lock actuator assembly has an actuator bar selectively and slidably positioned in said lock assembly cut-out. 17. The hinge of claim 16 wherein said lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and said actuator bar has a protrusion configured for close fitting within said first depression and said second depression when said actuator bar is selectively slid within said lock assembly cut-out. 18. The hinge of claim 14 wherein said rotation lock pin is transitionable between a locked position, wherein said rotation lock pin is selectively positioned within said one of said series of lock notches, and an unlocked position, wherein said rotation lock pin is selectively withdrawn from said one of said series of lock notches. 19. A hinge for an orthopedic brace comprising: a first external rotation plate having a first external peripheral edge, a first external inner face and a first external outer face; an internal rotation plate having an internal peripheral edge; a second external rotation plate having a second external peripheral edge, a second external inner face and a second external outer face; a pivotal connector connecting said first and second external rotation plates and said internal rotation plate; a rotation limiting mechanism including, a series of rotation limiting teeth formed in said first external inner face at said first external peripheral edge, a rotation limiting face formed in said internal peripheral edge, and a rotation limiting assembly having an engagement face selectively positionable between two adjacent teeth of said series of said teeth to place said rotation limiting assembly in a fixed position and having a stop face engageable with said rotation limiting face upon rotation of said internal rotation plate relative to said first external rotation plate in a first rotation direction to substantially limit further rotation of said internal rotation plate relative to said first external rotation plate in said first rotation direction; and a rotation locking mechanism including, a series of lock notches formed in said internal peripheral edge, a lock pin slot formed in said first and/or second external inner face, and a rotation lock pin slidably positioned in said lock pin slot and selectively positionable within one of said series of lock notches to substantially lock said first external rotation plate and said internal rotation plate against rotation of said internal rotation plate relative to said first external rotation plate in said first rotation direction or in a second rotation direction opposite said first rotation direction. 20. The hinge of claim 19 wherein said engagement face is a first engagement face, said rotation limiting mechanism further including a series of rotation limiting teeth formed in said second external inner face at said second external peripheral edge, a second engagement face of said rotation limiting assembly selectively positionable between two adjacent teeth of said series of said teeth in said second external inner face. | TECHNICAL FIELD The present invention relates generally to orthopedic braces, and more particularly to a hinge for an orthopedic brace, wherein the hinge has a mechanism for selectively adjusting the range of hinge rotation and a mechanism for releasably locking the hinge in a fixed position without altering the selected hinge rotation limits. BACKGROUND OF THE INVENTION Hinges for orthopedic braces having an adjustable rotation range in the extension and flexion direction are well known in the art. For example, U.S. Pat. No. 4,481,941 to Rolfes discloses a hinge having a pair of threaded screws, each being selectively threadably securable in one of a plurality of correspondingly threaded holes formed in the body of the hinge. The hinge rotation range is a function of screw placement insofar as securing a screw in a given hole determines a particular hinge rotation limit. The hinge rotation range is adjusted by changing the hinge rotation limit, which requires removal of the screw from its respective hole and placement of the screw in an alternate hole. However, It has been found that the task of adjusting the hinge rotation range can require a significant degree of dexterity to maneuver the relatively small screws into and out of the threaded holes. Furthermore, the screws are susceptible to being misplaced or lost during this task. An alternate adjustable hinge disclosed by U.S. Pat. No. 401,933 to De Camp, substitutes pins for threaded screws as a means for setting the hinge rotation limit. The smooth surface of the pins enables them to slide in and out of the holes formed in the body of the hinge. The pins are secured in the holes by a leaf spring attached to each pin which biases the pin into its respective hole in a direction parallel to the axis of hinge rotation. Repositioning the pins of De Camp requires less dexterity than repositioning the screws of Rolfes. Nevertheless, De Camp still requires the user to pry the leaf spring away from the hinge body and remove the pin from the hole when adjusting the hinge rotation range. Accordingly, hinges having an improved adjustment mechanism were developed and disclosed in U.S. Pat. Nos. 5,672,152 and 5,827,208 to Mason et al. The hinges of Mason et al. are relatively easy to set at a desired rotation limit in the extension or flexion direction and also have the desirable capability of being selectively lockable against rotation altogether. In accordance with one embodiment, the hinge of Mason et al. includes a plurality of rotation limiting notches and a locking notch formed in the peripheral edge of the hinge. A rotation limiting assembly is provided which is selectively positionable in one of the rotation limiting notches to define a hinge rotation limit. Alternatively, the rotation limiting assembly is selectively positionable in the locking notch to lock the hinge against rotation. The hinge also includes a biasing assembly which biases the rotation limiting assembly in a radially inward direction perpendicular to the axis of hinge rotation, thereby retaining the rotation limiting assembly in its selected rotation limiting position or locked position. The biasing assembly, however, enables elastic radial displacement of the rotation limiting assembly in a radially outward direction when a radially outward displacement force is externally applied thereto. The biasing assembly returns the rotation limiting assembly to a selected rotation limiting or locked position when the displacement force is withdrawn. Although the above-recited hinge of Mason et al. is a substantial improvement over the hinges of De Camp and Rolfes, it is noted that the hinge of Mason et al. utilizes the same rotation limiting assembly for two different functions. In particular, the rotation limiting assembly is used to set a desired hinge rotation limit as well as to selectively lock the hinge against rotation altogether. Therefore, it is necessary to remove the rotation limiting assembly from its selected rotation limiting position and place the rotation limiting assembly in the locked position when it is desired to lock the hinge against rotation. When it is desired to enable rotation by unlocking the hinge, the rotation limiting assembly is removed from the locked position and returned to its selected rotation limiting position. This sequence of steps inherently increases the risk of erroneously resetting the hinge rotation limit when the rotation limiting assembly is returned to the rotation limiting position if the user has forgotten or improperly locates the prior prescribed hinge rotation limit. Therefore, a need exists for a hinge for an orthopedic brace having an adjustable rotation range, further wherein the hinge is selective between a locked mode and an unlocked mode of operation without disrupting the selected hinge rotation limits. Accordingly, it is an generally an object of the present invention to provide a hinge for an orthopedic brace, which has an adjustable rotation range, and which has a locked and an unlocked mode of operation. More particularly, it is an object of the present invention to provide such a hinge having a rotation limiting mechanism, which selectively enables adjustment of the hinge rotation range, and also having a locking mechanism, which selectively enables locking the hinge against rotation altogether. It is still another object of the present invention to provide such a hinge, wherein the locking mechanism can be transitioned between the locked and unlocked modes without altering the rotation limits of the rotation limiting mechanism. These objects and others are accomplished in accordance with the invention described hereafter. SUMMARY OF THE INVENTION The present invention is a hinge for an orthopedic brace comprising a first rotation plate, a second rotation plate, a pivotal connector connecting the first and second rotation plates, a rotation limiting mechanism, and a rotation locking mechanism. The first rotation plate has a first peripheral edge, an inner face, and an outer face. The second rotation plate has a second peripheral edge. The rotation limiting mechanism includes a rotation limiting face formed in the second peripheral edge and a rotation limiting assembly selectively positionable in a fixed position relative to the first rotation plate. The rotation limiting assembly has a stop face engageable with the rotation limiting face upon rotation of the second rotation plate relative to the first rotation plate in a first rotation direction, which substantially limits further rotation of the second rotation plate relative to the first rotation plate in the first rotation direction. The rotation locking mechanism includes a rotation lock pin and a series of lock notches formed in the second peripheral edge. The rotation lock pin is selectively positionable within one of the series of lock notches, which substantially locks the first and second rotation plates against rotation of the second rotation plate relative to the first rotation plate in the first rotation direction or in a second rotation direction opposite the first rotation direction. In accordance with specific embodiments, the rotation limiting mechanism includes a series of rotation limiting teeth formed in the inner face at the first peripheral edge. The rotation limiting assembly has an engagement face which is selectively positionable between two adjacent teeth of the series of teeth to place the rotation limiting assembly in the fixed position. The rotation limiting mechanism further includes a biasing member biasing the engagement face radially inward from the first peripheral edge. The rotation locking mechanism includes a lock pin slot formed in the inner face and a lock actuator assembly engaging the rotation lock pin. The rotation lock pin is slidably positioned in the lock pin slot. The rotation lock pin has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the inner face. Alternatively or additionally, the lock pin slot has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the longitudinal axis of the lock pin slot. The rotation lock pin is transitionable between a locked position and an unlocked position. The rotation lock pin is transitioned to the locked position by selectively positioning the rotation lock pin within one of the series of lock notches as recited above. The rotation lock pin is transitioned to the unlocked position by selectively withdrawing the rotation lock pin from one of the series of lock notches so that the rotation lock pin does not substantially impede rotation of the second rotation plate relative to the first rotation plate in the first or second rotation direction. The rotation lock pin can be transitionable between the locked and unlocked positions without substantially modifying the fixed position of the rotation limiting assembly. The rotation locking mechanism further includes a lock transition plate and a lock actuator assembly engaging the rotation lock pin. The lock transition plate has a lock assembly cut-out and the lock actuator assembly has an actuator bar selectively and slidably positioned in the lock assembly cut-out. The lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and the actuator bar has a protrusion configured for close fitting within the first or second depression when the actuator bar is selectively slid within the lock assembly cut-out. In accordance with an alternate embodiment, the present invention is a hinge for an orthopedic brace comprising a first external rotation plate, an internal rotation plate, a second external rotation plate, a pivotal connector connecting the first and second external rotation plates and internal rotation plate, a rotation limiting mechanism, and a rotation locking mechanism. The first external rotation plate has a first external peripheral edge, a first external inner face and a first external outer face. The internal rotation plate has an internal peripheral edge. The second external rotation plate has a second external peripheral edge, a second external inner face and a second external outer face. The rotation limiting mechanism includes a series of rotation limiting teeth formed in the first external inner face at the first external peripheral edge, a rotation limiting face formed in the internal peripheral edge, and a rotation limiting assembly. The rotation limiting assembly has an engagement face selectively positionable between two adjacent teeth of the series of teeth to place the rotation limiting assembly in a fixed position. The rotation limiting assembly also has a stop face engageable with the rotation limiting face upon rotation of the internal rotation plate relative to the first external rotation plate in a first rotation direction which substantially limits further rotation of the internal rotation plate relative to the first external rotation plate in the first rotation direction. The rotation locking mechanism includes a series of lock notches formed in the internal peripheral edge, a rotation lock pin, and a lock pin slot. The lock pin slot is formed in the first and second external inner faces, is formed only in the first external inner face, or is formed only in the second internal face. The rotation lock pin is slidably positioned in the lock pin slot and is selectively positionable within one of the series of lock notches, which substantially locks the first external rotation plate and the internal rotation plate against rotation of the internal rotation plate relative to the first external rotation plate in the first rotation direction or in a second rotation direction opposite the first rotation direction. In accordance with a specific embodiment, the engagement face is a first engagement face and the rotation limiting mechanism further includes a series of rotation limiting teeth formed in the second external inner face at the second external peripheral edge. The rotation limiting assembly has a second engagement face selectively positionable between two adjacent teeth of the series of teeth in the second external inner face. In accordance with another alternate embodiment, the present invention is a rotation locking mechanism for a hinge of an orthopedic brace. The hinge has a first rotation plate with a first peripheral edge, an inner face and an outer face, a second rotation plate with a second peripheral edge, and a pivotal connector connecting the first and second rotation plates. The rotation locking mechanism comprises a rotation lock pin, a series of lock notches formed in the second peripheral edge, and a lock pin slot formed in the inner face. The rotation lock pin is slidably positioned in the lock pin slot and is selectively positionable within one of the series of lock notches, which substantially locks the first and second rotation plates against rotation of the second rotation plate relative to the first rotation plate in a first rotation direction or in a second rotation direction opposite the first rotation direction. The rotation locking mechanism further comprises a lock actuator assembly engaging the rotation lock pin. The rotation lock pin has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the inner face. The rotation locking mechanism further comprises a lock transition plate having a lock assembly cut-out. The lock actuator assembly has an actuator bar which is selectively and slidably positioned in the lock assembly cut-out. The lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and the actuator bar has a protrusion configured for close fitting within the first or second depression when the actuator bar is selectively slid within the lock assembly cut-out. The rotation lock pin is transitionable between a locked position and an unlocked position. The rotation lock pin is transitioned to the locked position by selectively positioning the rotation lock pin within one of the series of lock notches as recited above. The rotation lock pin is transitioned to the unlocked position by selectively withdrawing the rotation lock pin from one of the series of lock notches so that the rotation lock pin does not substantially impede rotation of the second rotation plate relative to the first rotation plate in the first or second rotation direction. The present invention will be further understood from the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a leg having an orthopedic brace employing the hinge of the present invention mounted thereon. FIGS. 2A and 2B are an exploded perspective view of the hinge of FIG. 1. FIG. 3 is a rear view of the inner face of a lateral exterior rotation plate included in the hinge of FIG. 1. FIG. 4 is a side elevational view of a rotation limiting assembly included in the hinge of FIG. 1. FIG. 5 is a front elevational view of a rotation limiting assembly included in the hinge of FIG. 1. FIG. 6 is a top view of a lock transition plate included in the hinge of FIG. 1. FIG. 7 is a side elevational view of a lock actuator assembly included in the hinge of FIG. 1. FIG. 8 is a bottom view of a lock actuator assembly included in the hinge of FIG. 1. FIG. 9 is a front elevational view of a lock actuator assembly included in the hinge of FIG. 1. FIG. 10 is a cutaway frontal view of the hinge of FIG. 1, wherein a rotation limiting mechanism of the hinge is in a rotation mode of operation and a rotation locking mechanism of the hinge is in an unlocked mode of operation. FIG. 11 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in a rotation limit adjustment mode of operation and the rotation locking mechanism is in the unlocked mode of operation. FIG. 12 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in the rotation mode of operation and the rotation locking mechanism is in a locked mode of operation. FIG. 13 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in the rotation mode of operation and the rotation locking mechanism is in the unlocked mode of operation and further wherein the hinge is rotated in a clockwise direction to a preselected first flexion rotation limit. FIG. 14 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in the rotation mode of operation and the rotation locking mechanism is in the unlocked mode of operation and further wherein the hinge is rotated in a counterclockwise direction to a preselected first extension rotation limit. FIG. 15 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in the rotation limit adjustment mode of operation and the rotation locking mechanism is in the unlocked mode of operation and further wherein the flexion rotation limit of the hinge is being adjusted from the first flexion rotation limit of FIG. 13 to a second flexion rotation limit. FIG. 16 is a cutaway frontal view of the hinge of FIG. 1, wherein the rotation limiting mechanism is in the rotation mode of operation and the rotation locking mechanism is in the unlocked mode of operation and further wherein the hinge is rotated in the clockwise direction to the second flexion rotation limit of FIG. 15. DESCRIPTION OF PREFERRED EMBODIMENTS Referring initially to FIG. 1, a hinged orthopedic brace is shown and generally designated 10. There are a number of relative terms defined below which are used in the following description to distinguish various elements of the brace 10 from one another, but which are not to be construed as limiting the scope of the invention. The relative terms “medial” and “lateral” characterize certain elements of the brace 10, which are positioned about the axis of rotation of the brace 10. The terms describe the relative proximity of the given element to the central longitudinal axis of the body of the user when the brace 10 is mounted thereon. In particular, a “medial” element is closer to the central longitudinal axis of the body, while a “lateral” element is further from the central longitudinal axis of the body. The relative terms “inner” and “outer” likewise characterize certain elements of the brace 10, which are positioned about the axis of rotation of the brace 10. However, the terms describe the relative proximity of the given element to the central longitudinal axis of the brace 10. An “inner” element is closer to the central longitudinal axis of the brace 10, while an “outer” element is further from the central longitudinal axis of the brace 10. The terms “proximal” and “distal” characterize certain elements of the brace 10, which are aligned with the longitudinal axis of the brace 10. The terms describe the relative proximity of the given element to the axis of rotation of the brace 10. A “proximal” element is closer to the axis of rotation of the brace 10, while a “distal” element is further from the axis of rotation of the brace 10. The terms “upper” and “lower” likewise characterize certain elements of the brace 10, which are aligned with the longitudinal axis of the brace 10. However, the terms describe the position of the given element as being either above or below a horizontal plane bisected by the axis of rotation of the brace 10. In particular, an “upper” element is above the horizontal plane bisecting the axis of rotation of the brace 10, while a “lower” element is below the horizontal plane bisecting the axis of rotation of the brace 10. The hinged orthopedic brace 10 comprises a hinge 12, an upper rotation arm 14, a lower rotation arm 16, an upper strap retainer 18 associated with the upper rotation arm 14, and a lower strap retainer 20 associated with the lower rotation arm 16. The upper strap retainer 18 maintains an upper strap 22 distally connected to the upper rotation arm 14, while the lower strap retainer 20 maintains a lower strap 24 distally connected to the lower rotation arm 16. For purposes of illustration, the hinged orthopedic brace 10 is a specific type of hinged orthopedic brace commonly termed a post-operative knee brace. The brace 10 is mounted on a right leg 26 of a user, which is characterized as having an upper leg 28, a lower leg 30 and a knee joint 32 rotationally connecting the upper and lower legs 28, 30. It is apparent to the skilled artisan that the post-operative knee brace 10 is alternatively adaptable for mounting on the left leg of a user. It is further apparent from the foregoing that the above-recited brace components 12, 14, 16, 18, 20, 22, 24 are readily adaptable to other types of hinged orthopedic braces for the knee and other joints of the body. Both the upper and lower rotation arms 14, 16 are preferably relatively rigid, being formed from a lightweight, high-strength material, such as aluminum or stainless steel. When the brace 10 is mounted on the leg 26, the upper rotation arm 14 is longitudinally aligned with the lateral side of the upper leg 28, the hinge 12 is aligned with the lateral side of the knee joint 32 and the lower rotation arm 16 is longitudinally aligned with the lateral side of the lower leg 30. In particular, the longitudinal axis of the upper rotation arm 16 is oriented substantially parallel to the longitudinal axis of the upper leg 28 and is retained in removable engagement with the upper leg 28 by means of the upper strap 22 and upper strap retainer 18. The longitudinal axis of the lower rotation arm 16 is oriented substantially parallel to the longitudinal axis of the lower leg 30 and is retained in removable engagement with the lower leg 30 by means of the lower strap 24 and lower strap retainer 20. Although not shown, it is within the scope of the present invention to provide relatively rigid, fitted, upper and lower leg cuffs attached to or integral with the upper and lower rotation arms 14, 16 which further secure the upper and lower rotation arms 14,16 to the upper and lower legs 28, 30, respectively. It is also within the scope of the present invention to provide additional straps and strap retainers which further secure the upper and lower rotation arms 14, 16 to the upper and lower legs 28, 30, respectively. It is further within the scope of the present invention to reverse the configuration of the brace 10 in a manner readily apparent to the skilled artisan so that the upper rotation arm 14 is repositioned in longitudinal alignment with the lateral side of the lower leg 30 and the lower rotation arm 16 is repositioned in longitudinal alignment with the lateral side of the upper leg 28, while the hinge 12 remains aligned with the lateral side of the knee joint 32. In another alternative, the upper rotation arm 14 can be longitudinally aligned with the medial side of the upper leg 28, the hinge 12 aligned with the medial side of the knee joint 32, and the lower rotation arm 16 longitudinally aligned with the medial side of the lower leg 30. This configuration can likewise be reversed so that the upper rotation arm 14 is repositioned in longitudinal alignment with the medial side of the lower leg 30 and the lower rotation arm 16 is repositioned in longitudinal alignment with the medial side of the upper leg 28, while the hinge 12 remains aligned with the medial side of the knee joint 32. Referring additionally to FIGS. 2A and 2B, the hinge 12 comprises a lateral exterior rotation plate 34, a medial exterior rotation plate 36, and an interior rotation plate 38 rotatably positioned between the lateral and medial exterior rotation plates 34, 36. The lateral and medial exterior rotation plates 34, 36 are fixably fastened to a proximal end 40 of the upper rotation arm 14 by conventional fasteners 42, such as rivets or the like, which extend through fastening apertures 44 provided in the exterior rotation plates 34, 36. The interior rotation plate 38 is integral with the lower rotation arm 16, being contiguous with a proximal end 46 of the lower rotation arm 16. Although not shown, alternate constructions of the rotation plates 34, 36, 38 in association with the rotation arms 14,16 are within the scope of the present invention. For example, one or both of the lateral and medial exterior rotation plates 34, 36 may be integral with the upper rotation arm 14, while the interior rotation plate 38 is fixably fastened to the lower rotation arm 16. Alternatively, one or both of the lateral and medial exterior rotation plates 34, 36 may be integral with the upper rotation arm 14, while the interior rotation plate 38 is similarly integral with the lower rotation arm 16. In yet another alternative, the interior rotation plate 38 may be fixably fastened to the lower rotation arm 16, while the lateral and medial exterior rotation plates 34, 36 are similarly fixably fastened to the upper rotation arm 14. The lateral and medial exterior rotation plates 34, 36 are both preferably formed from a relatively rigid, lightweight, high-strength material, such as a plastic, while the interior rotation plate 38 is preferably formed from the same material as the lower rotation arm 16. Referring additionally to FIG. 3, each exterior rotation plate 34, 36 has a substantially similar circular configuration with an inner face 48 and an outer face 50, which are bounded by a peripheral edge 52. A plurality of flexion rotation limit markers 53, extension rotation limit markers 54, and rotation lock markers 55 are preferably provided on the outer face 50 of the lateral exterior rotation plate 34. A lock reference marker 56 is preferably provided on the proximal end 46 of the lower rotation arm 16. Each flexion rotation limit marker 53 displays a specific flexion rotation limit value (e.g., 0°, 30°, etc.), which correlates to the flexion angle of the upper and lower rotation arms 14,16, and correspondingly of the knee joint 32, when the hinge 12 reaches the specific flexion rotation limit corresponding to that value in a manner described hereafter. Each extension rotation limit marker 54 similarly displays a specific extension rotation limit value (e.g., 0°, 30°, etc.), which correlates to the extension angle of the upper and lower rotation arms 14, 16, and correspondingly of the knee joint 32, when the hinge 12 reaches the specific extension rotation limit corresponding to that value in a manner described hereafter. Each rotation lock marker 55 displays a specific lock position value (e.g., 0°, 30°, etc., and further characterized as either flexion or extension), which correlates to the flexion or extension angle of the upper and lower rotation arms 14, 16, and correspondingly of the knee joint 32, when the hinge 12 is locked in the specific lock position corresponding to that value (expressed as a flexion or extension angle) in a manner described hereafter. The peripheral edge 52 defines the circumference of each exterior rotation plate 34, 36. The inner face 48 of each exterior rotation plate 34, 36 is preferably a smooth, flat, low-friction surface. The interior rotation plate 38 likewise has a substantially circular configuration with a lateral face 57 and a medial face 58, which are bounded by a peripheral edge 59. The peripheral edge 59 defines the circumference of the interior rotation plate 38. The lateral and medial faces 57, 58 of the interior rotation plate 38 are preferably smooth, flat, low-friction surfaces. Each of the rotation plates 34, 36, 38 is provided with a centrally-positioned pivot aperture 60 extending therethrough. A pivot member 62, having a diameter smaller than the pivot apertures 60, extends through all of the pivot apertures 60 and is fixably, but rotatably, retained therein. As such, the exterior rotation plates 34, 36 are freely rotatable in unison about the pivot member 62 relative to the interior rotation plate 36 when not impeded by the rotation limiting and locking mechanisms of the hinge 12 described hereafter. A preferred pivot member 62 is a rivet having a narrow body and flattened heads at either end, which engage the outer faces 50 of the lateral and medial exterior rotation plates 34, 36, respectively. A bushing (not shown) may also be provided which encloses the body of the pivot member 62 and eases rotation of the rotation plates 34, 36, 38 about the pivot member 62. Each exterior rotation plate 34, 36 has an integrally-formed fastening extension 64 extending from a segment 66 of the peripheral edge 52. The fastening extension 64 includes the fastening apertures 44 and provides a base for fastening the exterior rotation plates 34, 36 to the proximal end 40 of the upper rotation arm 14 as described above. A plurality of rotation limiting teeth 68 are circumferentially formed at uniform periodically spaced intervals in the inner face 48 of each exterior rotation plate 34, 36 at the peripheral edges 52. The rotation limiting teeth 68 extend in a continuum along the peripheral edge 52 except where the fastening extension 64 extends from the peripheral edge 52. Each rotation limiting tooth 68 of the lateral exterior rotation plate 34 is aligned at all times with a uniquely corresponding rotation limiting tooth 68 of the medial exterior rotation plate 36 when the hinge 12 is assembled. Furthermore, each rotation limiting tooth 68 of the lateral exterior rotation plate 34 and corresponding rotation limiting tooth 68 of the medial exterior rotation plate 36 is uniquely correlated with a specific flexion or extension rotation limit of the hinge 12. As such, each flexion rotation limit marker 53 displaying a given flexion rotation limit value is uniquely aligned with the rotation limiting tooth 68 correlated with that given flexion rotation limit. Similarly, each extension rotation limit marker 54 displaying a given extension rotation limit value is uniquely aligned with the rotation limiting tooth 68 correlated with that given extension rotation limit. The rotation limiting teeth 68 each have an identical configuration and are radially aligned relative to the exterior rotation plate 34, 36. Each adjacent pair of rotation limiting teeth 68 on the lateral exterior rotation plate 34 defines a receiving space 70 therebetween and each adjacent pair of rotation limiting teeth 68 on the medial exterior rotation plate 36 likewise defines a receiving space 70 therebetween. Each receiving space 70 of the lateral exterior rotation plate 34 is aligned at all times with a uniquely corresponding receiving space 70 of the medial exterior rotation plate 36 when the hinge 12 is assembled. The rotation limiting teeth 68 and receiving spaces 70 shown herein each has an essentially U-shaped profile, but it is understood that other configurations of the rotation limiting teeth and receiving spaces are possible within the scope of the present invention. A pair of closely-spaced, side-by-side lock pin slots 74 are also formed in the inner face 48 of each exterior rotation plate 34, 36. Each lock pin slot 74 has an identical closed-ended configuration with an oval shape and each is configured to receive a rotation lock pin 76 in a manner described hereafter. The lock pin slots 74 are positioned at the peripheral edge 52 of each exterior rotation plate 34, 36 along the segment 66 of the peripheral edge 52 from which the fastening extension 64 extends. The lock pin slots 74, like the rotation limiting teeth 68, extend radially relative to the exterior rotation plates 34, 36. Furthermore, each lock pin slot 74 of the lateral exterior rotation plate 34 is aligned at all times with the uniquely corresponding lock pin slot 74 of the medial exterior rotation plate 36 when the hinge 12 is assembled. Although the exterior rotation plates 34, 36 have a substantially similar construction, as described above, there are some structural distinctions between the lateral and medial exterior rotation plates 34, 36 which facilitate the function of the hinge 12. In particular, the medial exterior rotation plate 36 has an integrally-formed pivot housing 78 positioned on the inner face 48 at the pivot aperture 60. In contrast, the lateral exterior rotation plate 34 is devoid of any additional structure at the pivot aperture 60 so that the inner face 48 of the lateral exterior rotation plate 34 transitions directly into the pivot aperture 60. The pivot housing 78 is a tubular member which extends away from the inner face 48 about the rotation axis of the medial exterior rotation plate 36. The pivot housing 78 has an open passageway, which is continuous with the pivot aperture 60 of the medial exterior rotation plate 36. The open passageway of the pivot housing 78 also aligns with the pivot aperture 60 of the lateral exterior rotation plate 34. The pivot aperture 60 of the lateral exterior rotation plate 34 is slightly larger than the pivot aperture 60 of the medial exterior rotation plate 36 so that the outer wall of the pivot housing 78 is close-fittingly received into the pivot aperture 60 of the lateral exterior rotation plate 34 when the hinge 12 is assembled. The configuration of the fastening extensions 64 also differs between the lateral and medial exterior rotation plates 34, 36, respectively. The fastening extension 64 of the lateral exterior rotation plate 34 has an inner face 80 which is raised relative to the remainder of the inner face 48 of the lateral exterior rotation plate 34. The raised inner face 80 includes a transition plate indentation 82 for receiving a lock transition plate 84 therein in a manner described hereafter. An actuator aperture 86 is also provided through the fastening extension 64 of the lateral exterior rotation plate 34, which is positioned between the fastening apertures 44, for receiving a lock actuator assembly 88 therein in a manner described hereafter. In contrast, the fastening extension 64 of the medial exterior rotation plate 36 has an inner face 90 which is relatively level with the remainder of the inner face 48 with the exception of raised rails 91 which extend along the edges of the fastening extension 64 away from the center of the medial exterior rotation plate 36. The rotation limiting mechanism of the hinge 12 includes the rotation limiting teeth 68 and receiving spaces 70 of the exterior rotation plates 34, 36, a flexion rotation limiting assembly 92, an extension rotation limiting assembly 93, and elements of the peripheral edge 59 of the interior rotation plate 38 described hereafter. Referring additionally to FIGS. 4 and 5, the extension rotation limiting assembly 93 comprises a rotation limiting assembly plate 94 having a substantially circular planar configuration with an inner face 96 and an outer face 98 which are bounded by a peripheral edge 100. The peripheral edge 100 defines the circumference of the rotation limiting assembly plate 94, which is preferably smaller than the circumference of the exterior rotation plates 34, 36. The inner and outer faces 96, 98 of the rotation limiting assembly plate 94 are preferably smooth, flat, low-friction surfaces. The extension rotation limiting assembly 93 further comprises a stop post 102 affixed to the peripheral edge 100 of the rotation limiting assembly plate 94. The longitudinal axis of the stop post 102 is aligned essentially perpendicular to the planar faces 96, 98 of the rotation limiting assembly plate 94. The stop post 102 is serially segmented into a lateral head 103, a lateral stop slot 104, a lateral tooth slot 105 and bounding lateral engagement faces 106, a stop face 107, a medial tooth slot 108 and bounding medial engagement faces 109, a medial stop slot 110, and a medial head 112. A central portion of the stop post 102 is affixed to the peripheral edge 100 of the rotation limiting assembly plate 94, preferably at the intersection of the stop face 107 and the lateral engagement faces 106 or at the intersection of the stop face 107 and the medial engagement faces 109. As such, the lateral head 103, lateral stop slot 104, lateral tooth slot 105, lateral engagement faces 106, and stop face 107 are on one side of the rotation limiting assembly plate 94, while the medial tooth slot 108, medial engagement faces 109, medial stop slot 110, and medial head 112 are on the opposite side of the rotation limiting assembly plate 94, or alternatively the lateral head 103, lateral stop slot 104, lateral tooth slot 105, and lateral engagement faces 106 are on one side of the rotation limiting assembly plate 94, while the stop face 107, medial tooth slot 108, medial engagement faces 109, medial stop slot 110, and medial head 112 are on the opposite side of the rotation limiting assembly plate 94. The stop face 107 is defined by a notch formed in the stop post 102 between the lateral and medial engagement faces 106, 109. As such, the stop face 107 has a concave configuration relative to the lateral and medial engagement faces 106, 109. The height of the stop face 107 is preferably slightly greater than the height of the interior rotation plate 38 (i.e., the thickness of the peripheral edge 59) to receive the peripheral edge 59 therein. The lateral stop slot 104 and peripheral edge 52 of the lateral exterior rotation plate 34 are cooperatively configured so that the lateral stop slot 104 receives a portion of the peripheral edge 52 which is aligned with a receiving space 70. In particular, the lateral stop slot 104 and peripheral edge 52 are configured such that the height of the lateral stop slot 104 is slightly greater than the thickness of the portions of the peripheral edge 52 aligned with the receiving spaces 70. The rotation limiting teeth 68 and lateral tooth slot 105 are cooperatively configured so that a desired rotation limiting tooth 68 fits within the lateral tooth slot 105. The receiving spaces 70 and lateral engagement faces 106 are likewise cooperatively configured so that each lateral engagement face 106 fits within a desired receiving space 70 adjacent to the rotation limiting tooth 68 in the lateral tooth slot 105. The lateral head 103 is manually accessible to a user at a position adjacent to the outer face 50 of the lateral exterior rotation plate 34. The medial stop slot 110 and peripheral edge 52 of the medial exterior rotation plate 36 are similarly cooperatively configured so that the medial stop slot 110 receives a portion of the peripheral edge 52 which is aligned with a receiving space 70. The rotation limiting teeth 68 and medial tooth slot 108 are cooperatively configured so that a desired rotation limiting tooth 68 fits within the medial tooth slot 108. The receiving spaces 70 and medial engagement faces 109 are likewise cooperatively configured so that each medial engagement face 109 fits within a desired receiving space 70 adjacent to the rotation limiting tooth 68 in the medial tooth slot 108. The medial head 112 is manually accessible to a user at a position adjacent to the outer face 50 of the medial exterior rotation plate 36. A spring cut-out 114 is formed through the rotation limiting assembly plate 94. The spring cut-out 114 has a relatively narrow central channel 116, which has a closed end 117 and an opposite open end continuous with an adjoining relatively wide peripheral channel 118. The pivot member 62 and pivot housing 78 are received within the central channel 116, the width of the central channel 116 being only slightly greater than the outside diameter of the pivot housing 78. As such, the rotation limiting assembly plate 94 is freely rotatable about the pivot member 62 and pivot housing 78 relative to the rotation plates 34, 36, 38 when not impeded by the rotation limiting and locking mechanisms of the hinge 12. In contrast, the length of the central channel 116 is substantially greater than the outside diameter of the pivot housing 78. As such, the rotation limiting assembly plate 94 is also displaceable in a linear path about the pivot member 62 and pivot housing 78 along the length of the central channel 116 between a fixed position, which enables a rotation mode of operation of the rotation limiting mechanism of the hinge 12, and a rotation limit adjustment position, which enables a rotation limit adjustment mode of operation of the rotation limiting mechanism of the hinge 12, as described hereafter. However, the rotation limiting assembly plate 94 is essentially not linearly displaceable about the pivot member 62 and pivot housing 78 along the width of the central channel 116. A leaf spring 120 is provided, which is configured to conform to the profile of the spring cut-out 114 and is positioned therein. The leaf spring 120 has two straight end segments 122 joined by a U-shaped middle segment 124. The end segments 122 of the leaf spring 120 engage the walls of the peripheral channel 118, while the middle segment 124 of the leaf spring 120 engages the walls of the central channel 116 and the pivot housing 78. The leaf spring 120 biases the rotation limiting assembly plate 94 in the fixed position. When the rotation limiting assembly plate 94 is in the fixed position, the lateral and medial engagement faces 106, 109 of the stop post 102 are received within correspondingly aligned receiving spaces 70 of the lateral and medial external rotation plates 34, 36 and the rotation limiting teeth 68 are received within correspondingly aligned lateral and medial tooth slots 105, 108. The lateral and medial engagement faces 106, 109 and rotation limiting teeth 68 are retained in their respective positions by the radially-inward directed biasing force of the leaf spring 120. Engagement of the lateral and medial engagement faces 106, 109 and the rotation limiting teeth 68 prevents rotational displacement of the extension rotation limiting assembly 93 about the pivot member 62 relative to the rotation plates 34, 36, 38. The rotation limiting assembly plate 94 can be transitioned to the rotation limit adjustment position by applying a spring tensioning displacement force to the rotation limiting assembly plate 94 in a radially outward direction aligned with the longitudinal axis of the central channel 116. The displacement force is preferably applied to the rotation limiting assembly plate 94 by manually gripping the lateral and medial heads 103, 112 of the extension rotation limiting assembly 93 and pulling the lateral and medial heads 103, 112 radially outward. When the radially outward displacement force exceeds the biasing force of the leaf spring 120, the displacement force displaces the rotation limiting assembly plate 94 radially outward to withdraw the lateral and medial engagement faces 106, 109 from the receiving spaces 70 and the rotation limiting teeth 68 from the lateral and medial tooth slots 105, 108. As long as a sufficient displacement force is maintained on the rotation limiting assembly plate 94, the rotation limiting assembly plate 94 is retained in the rotation limit adjustment position and the extension rotation limiting assembly 93 is freely rotatable about the pivot member 62 relative to the rotation plates 34, 36, 38. Once the displacement force is withdrawn, the biasing force of the leaf spring 120 returns the rotation limiting assembly plate 94 to the fixed position, which prevents further rotational displacement of the extension rotation limiting assembly 93 about the pivot member 62 relative to the rotation plates 34, 36, 38. The rotation limiting assembly plate 94 and stop post 102 are preferably integrally formed as a single unitary structure from a relatively rigid, lightweight, high-strength material, such as a plastic, which is the same or similar to that used to form the exterior rotation plates 34, 36. The leaf spring 120 is preferably a separate relatively elastic band formed from a lightweight, high-strength material, such as a malleable metal, e.g., copper. The flexion rotation limiting assembly 92 is substantially identical to the extension rotation limiting assembly 93 except that the orientation of the flexion rotation limiting assembly 92 is flipped 180° relative to the extension rotation limiting assembly 93 so that both rotation limiting assemblies 92, 93 can be rotated about the pivot member 62 and pivot housing 78 relative to the rotation plates 34, 36, 38 without interfering with one another. Accordingly, the flexion rotation limiting assembly 92 has a rotation limiting assembly plate, stop post and leaf spring which are essentially identical in structure and function to those of the extension rotation limiting assembly 93 described above and, as such, are identified by the same reference characters. When the hinge 12 is assembled, the inner face 48 of the lateral exterior rotation plate 34 adjoins the outer face 98 of the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92. The innerface 96 of the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 adjoins the lateral face 57 of the interior rotation plate 38. The inner face 48 of the medial exterior rotation plate 36 adjoins the outer face 98 of the rotation limiting assembly plate 94 of the extension rotation limiting assembly 93. The inner face 96 of the rotation limiting assembly plate 94 of the extension rotation limiting assembly 93 adjoins the medial face 58 of the interior rotation plate 38. Although not shown, the hinge 12 can alternately be assembled so that the inner face 48 of the lateral exterior rotation plate 34 adjoins the outer face 98 of the rotation limiting assembly plate 94 of the extension rotation limiting assembly 93. The inner face 96 of the rotation limiting assembly plate 94 of the extension rotation limiting assembly 93 adjoins the lateral face 57 of the interior rotation plate 38. The inner face 48 of the medial exterior rotation plate 36 adjoins the outer face 98 of the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92. The inner face 96 of the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 adjoins the medial face 58 of the interior rotation plate 38. The peripheral edge 59 of the interior rotation plate 38 has a rotation arc 126 of about 270°. The rotation arc 126 is bounded on one end by a flexion rotation limiting face 128, which functions in cooperation with the engagement faces 106, 109 of the flexion rotation limiting assembly 92 in a manner described hereafter. The rotation arc 126 is bounded on the opposite end by an extension rotation limiting face 130, which correspondingly functions in cooperation with the engagement faces 106, 109 of the extension rotation limiting assembly 93. The rotation arc 126 additionally has a plurality of lock notches 132 circumferentially formed in the peripheral edge 59 at spaced intervals along the rotation arc intermediately between the flexion and extension rotation limiting faces 128, 130. The lock notches 132 of the interior rotation plate 38 are elements of the rotation locking mechanism, which function in cooperation with the remaining elements of the rotation locking mechanism described hereafter. In addition to the lock notches 132, the rotation locking mechanism of the hinge 12 includes the lock pin slots 74 of the exterior rotation plates 34, 36, the rotation lock pins 76, the lock transition plate 84, and the lock actuator assembly 88. Referring additionally to FIG. 6, the lock transition plate 84 is a planar structure which is sized and configured to nest within the transition plate indentation 82 flush with the inner face 90 of the fastening extension 64 of the medial exterior rotation plate 36. A pair of fastening apertures 134 are formed through the lock transition plate 84, which correspond to the fastening apertures 44 of the exterior rotation plates 34, 36. The fastening apertures 134 are in alignment with the fastening apertures 44 when the hinge 12 is assembled, to receive the fasteners 42 therein. A lock assembly cut-out 136 and a pair of expansion slots 138 are also formed through the lock transition plate 84. The lock assembly cut-out 136 has an open end, a closed end and two parallel sides. The expansion slots 138 are closely positioned adjacent to the opposite sides of the lock assembly cut-out 136 and are essentially parallely aligned with one another and with the lock assembly cut-out 136. The small separation distance between each expansion slot 138 and the lock assembly cut-out 136 defines an expansion rail 140, which is a narrow strip of relatively flexible material. The edge 142 of each expansion rail 140 bordering the lock assembly cut-out 136 defines the parallel sides of the lock assembly cut-out 136. Each bordering edge 142 has a relatively smooth linear surface with the exception of an arcuately-shaped proximal indentation 144 and an arcuately-shaped distal indentation 146 formed adjacent to one another in the bordering edge 142. The proximal and distal indentations 144, 146 of the opposing bordering edges 142 are positioned in direct corresponding alignment with one another across the lock assembly cut-out 136. The lock transition plate 84 is preferably integrally formed as a single unitary structure from a relatively elastic, lightweight, high-strength material, such as a plastic. Referring additionally to FIGS. 7-9, the lock actuator assembly 88 comprises an actuator bar 148 having a proximal end 150, a distal end 152, and longitudinal sides 154 connecting the two ends 150, 152. The longitudinal sides 154 have a relatively smooth linear surface with the exception of an arcuate protrusion 156 formed on each longitudinal side 154 of the actuator bar 148 near the distal end 152. Each protrusion 156 is sized and configured in correspondence with the proximal and distal indentations 144, 146 of the lock transition plate 84, so that the contour of the protrusion 156 conforms closely to the contour of either the proximal indentation 144 or the distal indentation 146 when the protrusion 156 is positioned in one of the indentations 144 or 146. The actuator bar 148 is slidably retained in the lock assembly cut-out 136, wherein the longitudinal sides 154 of the actuator bar 148 are essentially parallely aligned with the bordering edges 142 of the expansion rails when the hinge 12 is assembled. A manually accessible actuator grip 158 is positioned adjacent to the outer face 50 of the lateral exterior rotation plate 34 and is connected to the distal end 152 of the actuator bar 148 through the actuator aperture 86 of the lateral exterior rotation plate 34. A lock pin retainer 160 is mounted on the proximal end 150 of the actuator bar 148. The lock pin retainer 160 includes a lateral pin retainer plate 161 and a medial pin retainer plate 162 positioned one atop the other and spaced a distance apart, which corresponds approximately to the thickness of the interior rotation plate 38. Each pin retainer plate 161, 162 has a pair of side-by-side pin apertures 164 formed therethrough and spaced a distance apart, which corresponds to the distance between the closely-spaced lock pin slots 74. Accordingly, there are a total of four pin apertures 164, two in the lateral pin retainer plate 161 and two in the medial pin retainer plate 162. One of the two rotation lock pins 76 is fixably mounted within the two pin apertures 164 aligned one atop the other in the two pin retainer plates 161, 162 and the remaining rotation lock pin 76 is fixably mounted within the remaining two vertically-aligned pin apertures 164. The ends 166 of each rotation lock pin 76 extend beyond the pin retainer plates 161, 162. One extended end 166 of each rotation lock pin 76 is slidably positioned in the adjoining lock pin slots 74 of the lateral exterior rotation plate 34 when the hinge 12 is assembled and the opposite extended end 166 of each rotation lock pin 76 is slidably positioned in the adjoining lock pin slots 74 of the medial exterior rotation plate 36. Each lock pin slot 74 and rotation lock pin 76 has a longitudinal axis. The longitudinal axes of the rotation lock pins 76 are aligned perpendicular to the inner faces of the 48 of the lateral and medial exterior rotation plates 34, 36 and are likewise aligned perpendicular to the longitudinal axes of the lock pin slots 74. The actuator bar 148, actuator grip 158, and pin retainer plates 161, 162 are preferably integrally formed as a single unitary structure from a relatively rigid, lightweight, high-strength material, such as a plastic, which is the same or similar to that used to form the exterior rotation plates 34, 36 and rotation limiting assemblies 92, 93. The rotation lock pins 76 are preferably separate relatively rigid rods formed from a lightweight, high-strength material, such as a metal, e.g. steel or aluminum. The rotation lock pins 76 are sized and configured to be received within the lock notches 132 on the peripheral edge 59 of the interior rotation plate 38. Operation of the rotation locking mechanism is effected by the positioning of the rotation lock pins 76 relative to the lock notches 132. In particular, placement of the rotation lock pins 76 and lock notches 132 in an unlocked position, wherein the rotation lock pins 76 are radially separated from the adjacent lock notches 132, enables an unlocked mode of operation of the rotation locking mechanism. Placement of the rotation lock pins 76 and lock notches 132 in a locked position, wherein the rotation lock pins 76 are fitted within adjacent lock notches 132, enables a locked mode of operation of the rotation locking mechanism. Method of Operation The modes of operation of the above-described hinge 12 and the corresponding positions of the hinge components are described hereafter with reference to the Figures. Referring initially to FIG. 10 in association with FIGS. 1-9, the rotation limiting mechanism of the hinge 12 is shown in the rotation mode of operation and the rotation locking mechanism of the hinge 12 is shown in the unlocked mode of operation. For clarity, the lateral exterior rotation plate 34, actuator grip 158 and lateral pin retainer plate 161 have been removed from the hinge 12 in the view of FIG. 10. In accordance with the rotation mode of operation, the flexion and extension rotation limiting assemblies 92, 93 are in the fixed position. More particularly, with specific reference to the flexion rotation limiting assembly 92, the rotation mode of operation comprises rotatably positioning the pivot housing 78 of the medial exterior rotation plate 36, which encloses the pivot member 62, within the central channel 116 of the spring cut-out 114 in the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 such that the pivot housing 78 is spaced a distance away from the closed end 117. The rotation mode of operation further comprises fitting a portion of the peripheral edge 52 aligned with a receiving space 70 of the medial exterior rotation plate 36 within the lateral stop slot 104 of the flexion rotation limiting assembly 92, fitting a desired rotation limiting tooth 68 of the medial exterior rotation plate 36 within the lateral tooth slot 105 of the flexion rotation limiting assembly 92, and fitting the lateral engagement faces 106 of the flexion rotation limiting assembly 92 within the receiving spaces 70 of the medial exterior rotation plate 36 adjacent to the rotation limiting tooth 68 in the lateral tooth slot 105. In addition, the lateral head 103 of the flexion rotation limiting assembly 92 is positioned adjacent to the outer face 50 of the medial exterior rotation plate 36. The biasing force of the leaf spring 120 maintains the position of the rotation limiting assembly plate 94 fixed relative to the pivot member 62 and pivot housing 78 preventing inadvertent repositioning of the rotation limiting assembly plate 94 during the rotation mode of operation. Although not shown in FIG. 10, the rotation mode of operation further comprises fitting a portion of the peripheral edge 52 aligned with the corresponding receiving space 70 of the lateral exterior rotation plate 34 within the medial stop slot 110 of the flexion rotation limiting assembly 92, fitting the corresponding rotation limiting tooth 68 of the lateral exterior rotation plate 34 within the lateral tooth slot 105 of the flexion rotation limiting assembly 92, and fitting the lateral engagement faces 106 of the flexion rotation limiting assembly 92 within the corresponding receiving spaces 70 of the lateral exterior rotation plate 34. In addition, the medial head 112 is positioned adjacent to the outer face 50 of the lateral exterior rotation plate 34. Only the lateral head 103 of the extension rotation limiting assembly 93 is shown in FIG. 10. However, it is understood that the components of the extension rotation limiting assembly 93, which correspond to like components of the flexion rotation limiting assembly 92, are positioned in a substantially similar manner to the above description relating to the flexion rotation limiting assembly 92. In accordance with the unlocked mode of operation, the lock actuator assembly 88 is in a distal or unlocked position. More particularly, the unlocked mode of operation comprises placing the actuator grip 158 connected to the distal end 152 of the actuator bar 148 at a distal position adjacent to the outer face 50 of the lateral exterior rotation plate 34. Distal positioning of the actuator grip 158 concurrently positions the extended ends 166 of the rotation lock pins 76 mounted within the lock pin retainer 160 at the proximal end 150 of the actuator bar 148 toward the distal end of the lock pin slots 74 in the medial exterior rotation plate 36. Although not shown, it is understood that the extended ends 166 of the rotation lock pins 76 are also positioned toward the distal end of the lock pin slots 74 in the lateral exterior rotation plate 34. The above-recited distal positions of the actuator grip 158 and rotation lock pins 76 are maintained by tightly fitting the protrusions 156 on the longitudinal sides 154 of the actuator bar 148 near the distal end 152 into the distal indentation 146 along the bordering edges 142 of the lock assembly cut-out 136 in the lock transition plate 84 to inhibit inadvertent slidable displacement of the actuator bar 148 and the associated actuator grip 158 and rotation lock pins 76 during the unlocked mode of operation. The effect of distally positioning the actuator grip 158 and rotation lock pins 76 as recited above is to radially separate the rotation lock pins 76 a sufficient distance from the lock notches 132 in the peripheral edge 59 of the interior rotation plate 38 so that the rotation locking mechanism does not substantially impede the rotation mode of operation of the rotation limiting mechanism, when the rotation locking mechanism is in the unlocked mode of operation. It is further noted that the medial pin retainer plate 162 is medially positioned essentially clear of the peripheral edge 59 of the interior rotation plate 38 and the lateral pin retainer plate 161 (not shown in FIG. 19) is laterally positioned essentially clear of the peripheral edge 59 so that neither pin retainer plate 161, 162 impedes rotation of the hinge 12 at any time during hinge operation. Referring to FIG. 11, the rotation limiting mechanism of the hinge 12 is shown in the rotation limit adjustment mode of operation, while the rotation locking mechanism of the hinge 12 is shown in the unlocked mode of operation. In accordance with the present depiction of the rotation limit adjustment mode of operation, the extension rotation limiting assembly 93 remains in the fixed position, while the flexion rotation limiting assembly 92 has been transitioned to the rotation limit adjustment position. However, it is readily apparent to the skilled artisan from the following description that the rotation limit adjustment mode of operation further encompasses transitioning the extension rotation limiting assembly 93 to the rotation limit adjustment position while the flexion rotation limiting assembly 92 remains in the fixed position or transitioning both the flexion and extension rotation limiting assemblies 92, 93 to the rotation limit adjustment position simultaneously. It is also apparent that the rotation locking mechanism of the hinge 12 can alternatively be in the locked mode of operation described hereafter, when the rotation limiting mechanism of the hinge 12 is in the rotation limit adjustment mode of operation. With specific reference to the flexion rotation limiting assembly 92, the rotation limit adjustment mode of operation comprises displacing the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 radially outward by applying a radially outward directed manual force to the medial head 103 to overcome the biasing force of the leaf spring 120. The leaf spring 120 is increasingly tensioned as the closed end 117 of the central channel 116 of the spring cut-out 114 in the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 is displaced toward the pivot housing 78 of the medial exterior rotation plate 36. At the same time, the lateral engagement faces 106 are radially withdrawn from the receiving spaces 70 and the corresponding rotation limiting tooth 68 is radially withdrawn from the lateral tooth slot 105. Transitioning the flexion rotation limiting assembly 92 to the rotation limit adjustment position enables rotation of the flexion rotation limiting assembly 92 about the pivot member 62 and pivot housing 78. Although not shown in FIG. 11, the rotation limit adjustment mode of operation may additionally or alternatively comprise displacing the rotation limiting assembly plate 94 of the flexion rotation limiting assembly 92 radially outward by applying a radially outward directed manual force to the medial head 112 to overcome the biasing force of the leaf spring 120. Increasingly tensioning the leaf spring 120 and displacing the closed end 117 of the central channel 116 toward the pivot housing 78 also simultaneously radially withdraws the medial engagement faces 109 from the corresponding receiving spaces 70 and the corresponding rotation limiting tooth 68 from the medial tooth slot 108. Referring to FIG. 12, the rotation limiting mechanism of the hinge 12 is shown in the rotation mode of operation, while the rotation locking mechanism of the hinge 12 is shown in the locked mode of operation. In accordance with the locked mode of operation, the lock actuator assembly 88 is transitioned from the distal or unlocked position to a proximal or locked position. More particularly, the locked mode of operation comprises manually gripping the actuator grip 158 and slidably displacing the actuator grip 158 in a radially inward direction from the distal position to a proximal position which is likewise adjacent to the outer face 50 of the lateral exterior rotation plate 34. Displacement of the actuator grip 158 is enabled by applying a manual displacement force to the actuator grip 158 which is sufficient to cause the protrusions 156 to press against the bordering edges 142 of the lock assembly cut-out 136 in the lock transition plate 84 and bow the expansion rails 140 outward in cooperation with the expansion slots 138. This provides sufficient clearance for the protrusions 156 to slide out of the distal indentation 146 and travel inwardly through the lock assembly cut-out 136 to the proximal indentation 144. Displacement of the actuator grip 158 concurrently effects slidable displacement of the extended ends 166 of the rotation lock pins 76 in a radially inward direction toward the proximal end of the lock pin slots 74 in the lateral and medial exterior rotation plates 34, 36. The above-recited proximal positions of the actuator grip 158 and rotation lock pins 76 are maintained by tightly fitting the protrusions 156 on the actuator bar 148 into the proximal indentation 144 to inhibit inadvertent slidable displacement of the actuator bar 148 and the associated actuator grip 158 and rotation lock pins 76 during the locked mode of operation. The effect of proximally positioning the actuator grip 158 and rotation lock pins 76 as recited above is to engage the rotation lock pins 76 within the lock notches 132 in the peripheral edge 59 of the interior rotation plate 38 so that the rotation locking mechanism substantially prevents the rotation mode of operation of the rotation limiting mechanism, when the rotation locking mechanism is in the locked mode of operation. The rotation locking mechanism enables the practitioner to select a desired locking point for the hinge 12 having a specific degree of rotation from a range of available locking points. The selected locking point is indicated by alignment of the lock reference marker 56 on the proximal end 46 of the lower rotation arm 16 with the selected rotation lock marker 56 on the outer face 50 of the lateral exterior rotation plate 34. An exemplary range of locking points available for selection is between −10° and 30° of extension, wherein the sequential locking points are at graduated intervals of 10°. The modes of operation of the rotation limiting and locking mechanisms of the hinge 12 are further described hereafter by way of example with reference to FIGS. 13-16. Referring initially to FIG. 13 in association with FIGS. 1-12, the rotation limiting mechanism is in the rotation mode of operation. The lower rotation arm 16 of the brace 10 is rotated about the hinge 12 in a first direction of rotation, which is clockwise as indicated by the arrow 168, until the hinge 12 reaches a preselected first flexion rotation limit where the flexion rotation limiting face 128 on the peripheral edge 59 of the interior rotation plate 38 engages the stop face 107 on the flexion rotation limiting assembly 92. The first flexion rotation limit is preselected in accordance with the rotation limit adjustment mode of operation described above. In the example of FIG. 13, the first flexion rotation limit is 600 as indicated by alignment of the lateral head 103 of the flexion rotation limiting assembly 92 with the 600 flexion rotation limit marker 53 on the outer face 50 of the lateral exterior rotation plate 34. An exemplary range of flexion rotation limits available for selection is between −10° and 120°, wherein the sequential flexion rotation limits are at graduated intervals of 10°. As noted above, each rotation limiting tooth 68 on the lateral exterior rotation plate 34 is uniquely correlated with a specific flexion or extension rotation limit of the hinge 12 and each flexion rotation limit marker 53 on the lateral exterior rotation plate 34 is aligned with the unique rotation limiting tooth 68 correlated with the flexion rotation limit value displayed by the marker 53. Thus, for example, when the lateral head 103 of the flexion rotation limiting assembly 92 is aligned with the flexion rotation limit marker 53 displaying a flexion rotation limit value of 60°, the rotation limiting tooth 68 correlated with the 60° flexion rotation limit is fitted in the lateral tooth slot 105 of the flexion rotation limiting assembly 92, and the hinge 12 is rotated to 60° flexion, the flexion rotation limiting face 128 on the peripheral edge 59 of the interior rotation plate 38 engages the stop face 107 of the flexion rotation limiting assembly 92. Referring to FIG. 14, the rotation limiting mechanism remains in the rotation mode of operation. The lower arm 16 of the brace 10 is rotated about the hinge 12 in a second direction of rotation, which is counterclockwise as indicated by the arrow 170, until the hinge 12 reaches a preselected first extension rotation limit where the extension rotation limiting face 130 on the peripheral edge 59 of the interior rotation plate 38 engages the stop face 107 on the extension rotation limiting assembly 93. The first extension rotation limit is likewise preselected in accordance with the rotation limit adjustment mode of operation described above. In the example of FIG. 14, the first extension rotation limit is 10° as indicated by alignment of the lateral head 103 of the extension rotation limiting assembly 93 with the 10° extension rotation limit marker 54 on the outer face 50 of the lateral exterior rotation plate 34. An exemplary range of extension rotation limits available for selection is between −10° and 30°, wherein the sequential extension rotation limits are at graduated intervals of 10°. As noted above, each rotation limiting tooth 68 on the lateral exterior rotation plate 34 is uniquely correlated with a specific flexion or extension rotation limit of the hinge 12 and each extension rotation limit marker 54 on the lateral exterior rotation plate 34 is aligned with the unique rotation limiting tooth 68 correlated with the extension rotation limit value displayed by the marker 54. Thus, for example, when the lateral head 103 of the extension rotation limiting assembly 93 is aligned with the extension rotation limit marker 54 displaying an extension rotation limit value of 10°, the rotation limiting tooth 68 correlated with the 10° extension rotation limit is fitted in the lateral tooth slot 105 of the extension rotation limiting assembly 93, and the hinge 12 is rotated to 10° extension, the extension rotation limiting face 130 on the peripheral edge 59 of the interior rotation plate 38 engages the stop face 107 of the extension rotation limiting assembly 93. It is further noted with reference to FIG. 14 that each pair of lock notches 132 on the peripheral edge 59 of the interior rotation plate 38 is uniquely correlated with a specific lock position of the hinge 12. In addition, the position of each rotation lock marker 55 relative to the rotation lock pins 76 is likewise uniquely correlated with a specific lock position of the hinge 12. Thus, for example, when the hinge 12 is rotated to 10° extension, the rotation lock marker 55 displaying a lock position value of 10° extension is aligned with the lock reference marker 56 on the lower rotation arm 16 and the rotation lock pins 76 are aligned with the pair of lock notches 132 correlated with a lock position corresponding to 10° extension. Once this alignment of the rotation lock marker 55, lock reference marker 56, rotation lock pins 76, and pair of lock notches 132 is achieved, the rotation locking mechanism can be transitioned to the locked mode of operation in the manner described above. It is apparent that the elements of the rotation locking mechanism are structurally distinct from the elements of the rotation limiting mechanism. Thus, none of the structural elements of the rotation locking mechanism are employed in the operation of the rotation limiting mechanism and vice versa. As a result, the lock position of the hinge 12 can be selected independent of the flexion and extension rotation limits of the hinge 12 as long as the selected value of the lock position is less than or equal to the value of the flexion or extension rotation limit. This is an advantageous feature of the present hinge because in most cases the practitioner is able to select the value of the lock position without changing the value of the flexion or extension rotation limit. Referring to FIG. 15, the rotation limiting mechanism is transitioned to the rotation limit adjustment mode of operation, wherein the preselected first flexion rotation limit of FIG. 13 is adjusted to a second flexion rotation limit in the clockwise direction of the arrow 168 in accordance with the rotation limit adjustment mode of operation described above. In the example of FIG. 15, the second flexion rotation limit is 110° as indicated by alignment of the lateral head 103 of the flexion rotation limiting assembly 92 with the 110° flexion rotation limit marker 53 on the outer face 50 of the lateral exterior rotation plate 34. Adjustment of the extension rotation limit can also be performed in a like manner to the above-described adjustment of the flexion rotation limit, as is readily apparent to the skilled artisan. Upon completion of the rotation limit adjustment mode of operation, operation of the rotation limiting mechanism is resumed in the rotation mode with the hinge 12 having an adjusted flexion and/or extension rotation limit. Referring to FIG. 16, the rotation limiting mechanism resumes the rotation mode of operation. The lower arm 16 of the brace 10 is rotated about the hinge 12 until the hinge 12 reaches the second flexion rotation limit selected in accordance FIG. 15 where the flexion rotation limiting face 128 on the peripheral edge 59 of the interior rotation plate 38 again engages the stop face 107 on the flexion rotation limiting assembly 92 in substantially the same as described above with reference to FIG. 13. While the forgoing preferred embodiments of the invention have been described and shown, it is understood that alternatives and modifications, such as those suggested and others, may be made thereto and fall within the scope of the invention. For example, the hinge 12 has been described above as having a pair of rotation lock pins 76 and a pair of rotation limiting assemblies 92, 93. However, a hinge having only a single rotation lock pin and/or a single rotation limiting assembly is alternatively within the purview of the skilled artisan and within the scope of the present invention. The hinge 12 has also been described above as having a pair of external rotation plates 34, 36 and an internal rotation plate 38. However, a hinge having only a single external rotation plate and internal rotation plate is alternatively within the purview of the skilled artisan and within the scope of the present invention. It is likewise readily apparent to the skilled artisan to modify or eliminate elements of the hinge, which are cooperative with the eliminated external rotation plate, rotation limiting assembly and/or rotation lock pin of the alternate embodiments. For example, the flexion and/or extension rotation limiting assemblies 92, 93, rotation lock pins 76, or lock actuator assembly 84 can be modified to accommodate such alternate embodiments. A hinge having two external rotation plates and a single internal rotation plate, but wherein only one of the external rotation plates includes the rotation limiting teeth 68, receiving spaces 70, and/or lock pin slots 74, is alternatively within the purview of the skilled artisan and within the scope of the present invention. In accordance with these alternate embodiments, one external rotation plate can include the rotation limiting teeth 68, receiving spaces 70, and lock pin slots 74, thereby supporting both the rotation limiting and rotation locking functions of the hinge, while the other external rotation plate is devoid of rotation limiting teeth, receiving spaces, and lock pin slots, thereby supporting neither the rotation limiting function nor the rotation locking function of the hinge. Alternatively, one external rotation plate can include the rotation limiting teeth 68 and receiving spaces 70, but not the lock pin slots 74, thereby only supporting the rotation limiting function of the hinge, while the other external rotation plate includes the lock pin slots 74, but not the rotation limiting teeth 68 and receiving spaces 70, thereby only supporting the rotation locking function of the hinge. | <SOH> BACKGROUND OF THE INVENTION <EOH>Hinges for orthopedic braces having an adjustable rotation range in the extension and flexion direction are well known in the art. For example, U.S. Pat. No. 4,481,941 to Rolfes discloses a hinge having a pair of threaded screws, each being selectively threadably securable in one of a plurality of correspondingly threaded holes formed in the body of the hinge. The hinge rotation range is a function of screw placement insofar as securing a screw in a given hole determines a particular hinge rotation limit. The hinge rotation range is adjusted by changing the hinge rotation limit, which requires removal of the screw from its respective hole and placement of the screw in an alternate hole. However, It has been found that the task of adjusting the hinge rotation range can require a significant degree of dexterity to maneuver the relatively small screws into and out of the threaded holes. Furthermore, the screws are susceptible to being misplaced or lost during this task. An alternate adjustable hinge disclosed by U.S. Pat. No. 401,933 to De Camp, substitutes pins for threaded screws as a means for setting the hinge rotation limit. The smooth surface of the pins enables them to slide in and out of the holes formed in the body of the hinge. The pins are secured in the holes by a leaf spring attached to each pin which biases the pin into its respective hole in a direction parallel to the axis of hinge rotation. Repositioning the pins of De Camp requires less dexterity than repositioning the screws of Rolfes. Nevertheless, De Camp still requires the user to pry the leaf spring away from the hinge body and remove the pin from the hole when adjusting the hinge rotation range. Accordingly, hinges having an improved adjustment mechanism were developed and disclosed in U.S. Pat. Nos. 5,672,152 and 5,827,208 to Mason et al. The hinges of Mason et al. are relatively easy to set at a desired rotation limit in the extension or flexion direction and also have the desirable capability of being selectively lockable against rotation altogether. In accordance with one embodiment, the hinge of Mason et al. includes a plurality of rotation limiting notches and a locking notch formed in the peripheral edge of the hinge. A rotation limiting assembly is provided which is selectively positionable in one of the rotation limiting notches to define a hinge rotation limit. Alternatively, the rotation limiting assembly is selectively positionable in the locking notch to lock the hinge against rotation. The hinge also includes a biasing assembly which biases the rotation limiting assembly in a radially inward direction perpendicular to the axis of hinge rotation, thereby retaining the rotation limiting assembly in its selected rotation limiting position or locked position. The biasing assembly, however, enables elastic radial displacement of the rotation limiting assembly in a radially outward direction when a radially outward displacement force is externally applied thereto. The biasing assembly returns the rotation limiting assembly to a selected rotation limiting or locked position when the displacement force is withdrawn. Although the above-recited hinge of Mason et al. is a substantial improvement over the hinges of De Camp and Rolfes, it is noted that the hinge of Mason et al. utilizes the same rotation limiting assembly for two different functions. In particular, the rotation limiting assembly is used to set a desired hinge rotation limit as well as to selectively lock the hinge against rotation altogether. Therefore, it is necessary to remove the rotation limiting assembly from its selected rotation limiting position and place the rotation limiting assembly in the locked position when it is desired to lock the hinge against rotation. When it is desired to enable rotation by unlocking the hinge, the rotation limiting assembly is removed from the locked position and returned to its selected rotation limiting position. This sequence of steps inherently increases the risk of erroneously resetting the hinge rotation limit when the rotation limiting assembly is returned to the rotation limiting position if the user has forgotten or improperly locates the prior prescribed hinge rotation limit. Therefore, a need exists for a hinge for an orthopedic brace having an adjustable rotation range, further wherein the hinge is selective between a locked mode and an unlocked mode of operation without disrupting the selected hinge rotation limits. Accordingly, it is an generally an object of the present invention to provide a hinge for an orthopedic brace, which has an adjustable rotation range, and which has a locked and an unlocked mode of operation. More particularly, it is an object of the present invention to provide such a hinge having a rotation limiting mechanism, which selectively enables adjustment of the hinge rotation range, and also having a locking mechanism, which selectively enables locking the hinge against rotation altogether. It is still another object of the present invention to provide such a hinge, wherein the locking mechanism can be transitioned between the locked and unlocked modes without altering the rotation limits of the rotation limiting mechanism. These objects and others are accomplished in accordance with the invention described hereafter. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention is a hinge for an orthopedic brace comprising a first rotation plate, a second rotation plate, a pivotal connector connecting the first and second rotation plates, a rotation limiting mechanism, and a rotation locking mechanism. The first rotation plate has a first peripheral edge, an inner face, and an outer face. The second rotation plate has a second peripheral edge. The rotation limiting mechanism includes a rotation limiting face formed in the second peripheral edge and a rotation limiting assembly selectively positionable in a fixed position relative to the first rotation plate. The rotation limiting assembly has a stop face engageable with the rotation limiting face upon rotation of the second rotation plate relative to the first rotation plate in a first rotation direction, which substantially limits further rotation of the second rotation plate relative to the first rotation plate in the first rotation direction. The rotation locking mechanism includes a rotation lock pin and a series of lock notches formed in the second peripheral edge. The rotation lock pin is selectively positionable within one of the series of lock notches, which substantially locks the first and second rotation plates against rotation of the second rotation plate relative to the first rotation plate in the first rotation direction or in a second rotation direction opposite the first rotation direction. In accordance with specific embodiments, the rotation limiting mechanism includes a series of rotation limiting teeth formed in the inner face at the first peripheral edge. The rotation limiting assembly has an engagement face which is selectively positionable between two adjacent teeth of the series of teeth to place the rotation limiting assembly in the fixed position. The rotation limiting mechanism further includes a biasing member biasing the engagement face radially inward from the first peripheral edge. The rotation locking mechanism includes a lock pin slot formed in the inner face and a lock actuator assembly engaging the rotation lock pin. The rotation lock pin is slidably positioned in the lock pin slot. The rotation lock pin has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the inner face. Alternatively or additionally, the lock pin slot has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the longitudinal axis of the lock pin slot. The rotation lock pin is transitionable between a locked position and an unlocked position. The rotation lock pin is transitioned to the locked position by selectively positioning the rotation lock pin within one of the series of lock notches as recited above. The rotation lock pin is transitioned to the unlocked position by selectively withdrawing the rotation lock pin from one of the series of lock notches so that the rotation lock pin does not substantially impede rotation of the second rotation plate relative to the first rotation plate in the first or second rotation direction. The rotation lock pin can be transitionable between the locked and unlocked positions without substantially modifying the fixed position of the rotation limiting assembly. The rotation locking mechanism further includes a lock transition plate and a lock actuator assembly engaging the rotation lock pin. The lock transition plate has a lock assembly cut-out and the lock actuator assembly has an actuator bar selectively and slidably positioned in the lock assembly cut-out. The lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and the actuator bar has a protrusion configured for close fitting within the first or second depression when the actuator bar is selectively slid within the lock assembly cut-out. In accordance with an alternate embodiment, the present invention is a hinge for an orthopedic brace comprising a first external rotation plate, an internal rotation plate, a second external rotation plate, a pivotal connector connecting the first and second external rotation plates and internal rotation plate, a rotation limiting mechanism, and a rotation locking mechanism. The first external rotation plate has a first external peripheral edge, a first external inner face and a first external outer face. The internal rotation plate has an internal peripheral edge. The second external rotation plate has a second external peripheral edge, a second external inner face and a second external outer face. The rotation limiting mechanism includes a series of rotation limiting teeth formed in the first external inner face at the first external peripheral edge, a rotation limiting face formed in the internal peripheral edge, and a rotation limiting assembly. The rotation limiting assembly has an engagement face selectively positionable between two adjacent teeth of the series of teeth to place the rotation limiting assembly in a fixed position. The rotation limiting assembly also has a stop face engageable with the rotation limiting face upon rotation of the internal rotation plate relative to the first external rotation plate in a first rotation direction which substantially limits further rotation of the internal rotation plate relative to the first external rotation plate in the first rotation direction. The rotation locking mechanism includes a series of lock notches formed in the internal peripheral edge, a rotation lock pin, and a lock pin slot. The lock pin slot is formed in the first and second external inner faces, is formed only in the first external inner face, or is formed only in the second internal face. The rotation lock pin is slidably positioned in the lock pin slot and is selectively positionable within one of the series of lock notches, which substantially locks the first external rotation plate and the internal rotation plate against rotation of the internal rotation plate relative to the first external rotation plate in the first rotation direction or in a second rotation direction opposite the first rotation direction. In accordance with a specific embodiment, the engagement face is a first engagement face and the rotation limiting mechanism further includes a series of rotation limiting teeth formed in the second external inner face at the second external peripheral edge. The rotation limiting assembly has a second engagement face selectively positionable between two adjacent teeth of the series of teeth in the second external inner face. In accordance with another alternate embodiment, the present invention is a rotation locking mechanism for a hinge of an orthopedic brace. The hinge has a first rotation plate with a first peripheral edge, an inner face and an outer face, a second rotation plate with a second peripheral edge, and a pivotal connector connecting the first and second rotation plates. The rotation locking mechanism comprises a rotation lock pin, a series of lock notches formed in the second peripheral edge, and a lock pin slot formed in the inner face. The rotation lock pin is slidably positioned in the lock pin slot and is selectively positionable within one of the series of lock notches, which substantially locks the first and second rotation plates against rotation of the second rotation plate relative to the first rotation plate in a first rotation direction or in a second rotation direction opposite the first rotation direction. The rotation locking mechanism further comprises a lock actuator assembly engaging the rotation lock pin. The rotation lock pin has a longitudinal axis and the lock actuator assembly maintains the longitudinal axis of the rotation lock pin substantially perpendicular to the inner face. The rotation locking mechanism further comprises a lock transition plate having a lock assembly cut-out. The lock actuator assembly has an actuator bar which is selectively and slidably positioned in the lock assembly cut-out. The lock assembly cut-out has a bordering edge with a first depression and a second depression formed therein and the actuator bar has a protrusion configured for close fitting within the first or second depression when the actuator bar is selectively slid within the lock assembly cut-out. The rotation lock pin is transitionable between a locked position and an unlocked position. The rotation lock pin is transitioned to the locked position by selectively positioning the rotation lock pin within one of the series of lock notches as recited above. The rotation lock pin is transitioned to the unlocked position by selectively withdrawing the rotation lock pin from one of the series of lock notches so that the rotation lock pin does not substantially impede rotation of the second rotation plate relative to the first rotation plate in the first or second rotation direction. The present invention will be further understood from the drawings and the following detailed description. | 20050112 | 20070626 | 20060713 | 66116.0 | A61F500 | 1 | ALI, SHUMAYA B | RELEASABLY LOCKING HINGE FOR AN ORTHOPEDIC BRACE HAVING ADJUSTABLE ROTATION LIMITS | UNDISCOUNTED | 0 | ACCEPTED | A61F | 2,005 |
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11,039,566 | ACCEPTED | Light emitting diodes including barrier layers/sublayers and manufacturing methods therefor | Semiconductor light emitting devices, such as light emitting diodes, include a substrate, an epitaxial region on the substrate that includes a light emitting region such as a light emitting diode region, and a multilayer conductive stack including a reflector layer, on the epitaxial region. A barrier layer is provided on the reflector layer and extending on a sidewall of the reflector layer. The multilayer conductive stack can also include an ohmic layer between the reflector and the epitaxial region. The barrier layer further extends on a sidewall of the ohmic layer. The barrier layer can also extend onto the epitaxial region outside the multilayer conductive stack. The barrier layer can be fabricated as a series of alternating first and second sublayers. | 1. A semiconductor light emitting device comprising: a substrate; an epitaxial region on the substrate that includes therein a light-emitting region; a multilayer conductive stack comprising a reflector layer including a reflector layer sidewall, on the epitaxial region, and an ohmic contact layer including an ohmic contact layer sidewall, between the reflector layer and the epitaxial region; and a conductive barrier layer directly on the reflector layer and extending directly on the reflector layer sidewall and directly on the ohmic contact layer sidewall. 2. A light emitting device according to claim 1 wherein the conductive barrier layer further extends onto the epitaxial region outside the multilayer conductive stack. 3. A light emitting device according to claim 1 wherein the conductive barrier layer comprises a plurality of first and second alternating sublayers. 4. A light emitting device according to claim 3 wherein the first sublayers include grain boundaries therein and wherein the second sublayers are substantially free of grain boundaries. 5. A light emitting device according to claim 3 wherein the first sublayers include grain boundaries therein that are arranged such that the grain boundaries define an offset brick wall structure in the first sublayers. 6. A light emitting device according to claim 3 wherein the first sublayers comprise titanium tungsten and wherein the second sublayers comprise platinum, titanium and/or nickel. 7. A light emitting device according to claim 5 wherein the first sublayers comprise titanium tungsten and wherein the second sublayers comprise platinum, titanium and/or nickel. 8. A light emitting device according to claim 3 wherein the first sublayers are configured to reduce migration of metal from the reflector layer and wherein the second sublayers are configured to prevent at least some grain boundaries in the first sublayers from propagating thereacross. 9. A light emitting device according to claim 5 wherein the first sublayers are configured to reduce migration of metal from the reflector layer and wherein the second sublayers are configured to prevent at least some grain boundaries in the first sublayers from propagating thereacross. 10. A light emitting device according to claim 3 wherein the second sublayers are thinner than the first sublayers. 11. A light emitting device according to claim 3 wherein the plurality of first and second alternating sublayers include a first sublayer that is closest to the reflector layer and a first sublayer that is furthest from the reflector layer. 12. A light emitting device according to claim 11 wherein the first sublayer that is furthest from the reflector layer is thicker than the first sublayer that is closest to the reflector layer. 13. A light emitting device according to claim 7 wherein the second sublayers are thinner than the first sublayers. 14. A light emitting device according to claim 13 wherein the plurality of first and second alternating sublayers include a first sublayer that is closest to the reflector layer and a first sublayer that is furthest from the reflector layer. 15. A light emitting device according to claim 14 wherein the first sublayer that is furthest from the reflector layer is thicker than the first sublayer that is closest to the reflector layer. 16. A light emitting device according to claim 3 wherein the first sublayers comprise titanium tungsten sublayers that are about 1000 Å thick and wherein the second sublayers comprise platinum sublayers that are about 500 Å thick. 17. A light emitting device according to claim 15 wherein the first sublayers comprise titanium tungsten sublayers that are about 1000 Å thick, wherein the second sublayers comprise platinum sublayers that are about 500 Å thick, wherein the first sublayer that is closest to the reflector layer comprises a titanium tungsten sublayer that is about 1000 Å thick and wherein the first sublayer that is farthest from the reflector layer comprises a titanium tungsten sublayer that is about 5000 Å thick. 18. A light emitting device according to claim 1 wherein the conductive barrier layer is configured to prevent at least some cracks from occurring therein, adjacent the reflector layer sidewall. 19. A light emitting device according to claim 1 wherein the substrate comprises silicon carbide and the epitaxial region comprises gallium nitride. 20. A light emitting diode according to claim 1 wherein the ohmic contact layer comprises platinum, palladium, nickel/gold, nickel oxide/gold, nickel oxide/platinum, titanium and/or titanium/gold and wherein the reflector layer comprises aluminum and/or silver. 21. A light emitting device according to claim 1 wherein the reflector layer comprises silver. 22. A light emitting device according to claim 3 wherein the first sublayers are sufficiently thick to reduce migration of metal from the reflector but sufficiently thin to prevent at least some cracking of the first sublayers and wherein the second sublayers are sufficiently thick to prevent at least some grain boundaries in the first sublayers from propagating thereacross but sufficiently thin so as not to degrade resistance of the multilayer conductive stack. 23. A method of manufacturing a semiconductor light emitting device that includes a substrate, an epitaxial region on the substrate that includes therein a device region and a multilayer conductive stack comprising a reflector layer including a reflector layer sidewall on the epitaxial region, and an ohmic contact layer including an ohmic contact layer sidewall, between the reflector layer and the epitaxial region, the method comprising: forming a conductive barrier layer directly on the reflector layer that extends directly on the reflector layer sidewall and directly on the ohmic contact layer sidewall. 24. A method according to claim 23 wherein the forming further comprises: forming a conductive barrier layer directly on the reflector layer and extending directly on the reflector layer sidewall, directly on the ohmic layer sidewall and directly onto the epitaxial region outside the multilayer conductive stack. 25. A method according to claim 23 further comprising: forming the barrier layer as a plurality of alternating first and second sublayers. 26. A method according to claim 25 wherein the first sublayers include grain boundaries therein that are arranged such that the grain boundaries define an offset brick wall structure of the first sublayers. 27. A method according to claim 25 wherein the forming the barrier layer as a plurality of first and second alternating sublayers further comprises forming the second sublayers to be thinner than the first sublayers. 28. A method according to claim 25 further comprising: terminating the plurality of alternating first and second sublayers with a first sublayer to define an outer sublayer. 29. A method according to claim 28 wherein the outer sublayer is thicker than the first sublayers. 30. A method according to claim 25 wherein the second sublayers are thinner than the first sublayers. 31. A method according to claim 25 wherein the substrate comprises silicon carbide and the epitaxial region comprises gallium nitride. 32. A method according to claim 25 wherein the reflector layer comprises silver. 33. A method according to claim 25 wherein the forming the barrier layer as a plurality of first and second alternating sublayers comprises: forming the first sublayers sufficiently thick to reduce migration of metal from the reflector but sufficiently thin to prevent cracking of the first sublayers and forming the second sublayers sufficiently thick to prevent at least some grain boundaries in the first sublayers from propagating thereacross but sufficiently thin so as not to degrade resistance of the multilayer conductive stack. | CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a continuation of PCT International Application No. PCT/JUS2003/021909, having an international filing date of Jul. 15, 2003. This application also claims the benefit of provisional Application Ser. No. 60/450,960, filed Feb. 28, 2003 to Slater et al., entitled Light Emitting Diodes Including Modifications for Submount Bonding and Manufacturing Methods Therefor, and is a continuation-in-part (CIP) of application Ser. No. 10/200,244, filed Jul. 22, 2002, to Slater et al., entitled Light Emitting Diodes Including Modifications for Submount Bonding and Manufacturing Methods Therefor, which itself claims the benefit of and priority from Provisional Application Ser. No. 60/352,941, filed Jan. 30, 2002, entitled LED Die Attach Methods and Resulting Structures, Provisional Application Ser. No. 60/307,311, filed Jul. 23, 2001, entitled Flip Chip Bonding of Light Emitting Diodes, and Provisional Application Ser. No. 60/307,234, filed Jul. 23, 2001 entitled Thermosonic Bonding of Flip Chip Light-Emitting Diodes, and is also a CIP of application Ser. No. 10/057,821, filed Jan. 25, 2002, entitled Light Emitting Diodes Including Modifications for Light Extraction and Manufacturing Methods Therefor, the disclosures of all of which are hereby incorporated herein by reference in their entirety as if set forth fully herein. FIELD OF THE INVENTION This invention relates to microelectronic devices and fabrication methods therefor, and more particularly to light emitting devices, such as light emitting diodes (LEDs) and manufacturing methods therefor. BACKGROUND OF THE INVENTION Light emitting diodes are widely used in consumer and commercial applications. As is well known to those having skill in the art, a light emitting diode generally includes a diode region on a microelectronic substrate. The microelectronic substrate may comprise, for example, gallium arsenide, gallium phosphide, alloys thereof, silicon carbide and/or sapphire. Continued developments in LEDs have resulted in highly efficient and mechanically robust light sources that can cover the visible spectrum and beyond. These attributes, coupled with the potentially long service life of solid state devices, may enable a variety of new display applications, and may place LEDs in a position to compete with the well entrenched incandescent and fluorescent lamps. Gallium Nitride (GaN)-based LEDs typically comprise an insulating or semiconducting substrate such as silicon carbide (SiC) or sapphire on which a plurality of GaN-based epitaxial layers are deposited. The epitaxial layers comprise an active or diode region having a p-n junction which emits light when energized. LEDs may be mounted substrate side down onto a submount, also called a package or lead frame (hereinafter referred to as a “submount”). In contrast, flip-chip mounting of light emitting diodes involves mounting the LED onto the submount with the substrate side facing up (i.e. away from the submount). Light may be extracted and emitted through the substrate. Flip chip mounting may be an especially desirable technique for mounting SiC-based LEDs. In particular, since SiC has a higher index of refraction than GaN, light generated in the active or diode region generally does not totally internally reflect (i.e. reflect back into the GaN-based layers) at the GaN/SiC interface. Flip chip mounting of SiC-based LEDs also can improve the effect of certain substrate-shaping techniques known in the art. Flip chip packaging of SiC LEDs may have other benefits, such as improved heat dissipation, which may be desirable depending on the particular application for the LED. Because of the high index of refraction of SiC, light passing through an SiC substrate tends to be totally internally reflected into the substrate at the surface of the substrate unless the light strikes the surface at a fairly low angle of incidence (i.e. fairly close to normal). The critical angle for total internal reflection generally depends on the material with which SiC forms an interface. It is possible to increase the light output from an SiC-based LED by shaping the SiC substrate in a manner that limits total internal reflection by causing more rays to strike the surface of the SiC at low angles of incidence. A number of such shaping techniques and resulting devices are taught in U.S. patent application Ser. No. 10/057,821 to Slater et al, corresponding to U.S. Publication No. US 2002/0123164 A1, published Sep. 5, 2002, entitled Light Emitting Diodes Including Modifications for Light Extraction and Manufacturing Methods Therefor. One potential problem with flip-chip mounting is that when an LED is mounted on a submount using conventional techniques, a conductive die attach material such as silver epoxy is deposited on the LED and/or on the package, and the LED and the submount are pressed together. This can cause the viscous conductive die attach material to squeeze out and make contact with the N-type substrate and/or layers in the device, thereby forming a Schottky diode connection that can short-circuit the p-n junction in the active region. Metal-metal bonds formed by soldering, thermosonic scrubbing and/or thermocompression bonding are alternative attach techniques. However, tin (Sn) is a component of most types of solder, and migration of Sn from the bonded surface into the device can cause unwanted degradation of the device. Such migration can interfere with metal-semiconductor interfaces such as ohmic contacts and/or the function of metal-metal interfaces such as reflective interfaces that serve as mirrors. SUMMARY OF THE INVENTION Semiconductor light emitting devices such as light emitting diodes, according to some embodiments of the present invention, include a substrate, an epitaxial region on the substrate that includes therein a light emitting region such as a light emitting diode region, and a multilayer conductive stack comprising a reflector layer including a reflector layer sidewall, on the epitaxial region. A barrier layer is provided on the reflector layer and extending on the reflector layer sidewall. In other embodiments, the multilayer conductive stack further comprises an ohmic layer, including an ohmic layer sidewall, between the reflector and the epitaxial region. The barrier layer further extends on the ohmic layer sidewall. In still other embodiments of the present invention, the barrier layer further extends onto the epitaxial region outside the multilayer conductive stack. In other embodiments of the present invention, the barrier layer comprises a plurality of first and second alternating sublayers. In some embodiments, the first sublayers include grain boundaries therein and the second sublayers are substantially free of grain boundaries. In other embodiments, the first sublayers include grain boundaries that are arranged such that the grain boundaries define an offset brick wall structure of the first sublayers. In still other embodiments, the first sublayers comprise titanium tungsten and the second sublayers comprise platinum, titanium and/or nickel. In some embodiments, the first sublayers are configured to reduce migration of metal from the reflector layer, and the second sublayers are configured to prevent at least some grain boundaries in the first sublayers for propagating thereacross. In other embodiments, the plurality of first and second alternating sublayers define first and second outer sublayers that comprise the first sublayer. In still other embodiments, the second outer sublayer is thicker than the first outer sublayer. Other embodiments of the invention provide methods of reducing migration of metal from the reflective layer into the epitaxial region of a semiconductor light emitting device, by forming a barrier layer on the reflector layer that extends on the reflector layer sidewall. In other embodiments, the barrier layer is formed to extend on the ohmic layer sidewall. In still other embodiments, the barrier layer extends onto the epitaxial region outside the multilayer conductive stack. Still other embodiments of the present invention form the barrier layer as a plurality of alternating first and second sublayers, which can reduce cracking of the barrier layer adjacent the reflector layer sidewall. The first and second sublayers can define an offset brick wall structure that can terminate with a first sublayer, to define an outer sublayer, wherein the second sublayers are thinner than the first sublayers and the outer sublayer is thicker than the first sublayers. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1-10 are cross-sectional views of light emitting diodes according to some embodiments of the present invention during intermediate fabrication steps according to some embodiments of the present invention. FIGS. 11A-12D graphically illustrate test results for light emitting diodes according to some embodiments of the present invention. FIGS. 13-15 are cross-sectional views of light emitting diodes according to other embodiments of the present invention. FIGS. 16 and 17 are SEM images of light emitting diodes according to other embodiments of the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention now will be described more fully hereinafter with reference to the accompanying figures, in which embodiments of the present invention are shown. This invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein. Accordingly, while the present invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the present invention to the particular forms disclosed, but on the contrary, the present invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the claims. Like numbers refer to like elements throughout the description of the figures. In the figures, the dimensions of layers and regions may be exaggerated for clarity. It will also be understood that when an element, such as a layer, region or substrate, is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element, such as a layer, region or substrate, is referred to as being “directly on” another element, there are no intervening elements present. Moreover, each embodiment described and illustrated herein includes its complementary conductivity type embodiment as well. Embodiments of the present invention now will be described generally with reference to gallium nitride-based light emitting diodes on silicon carbide-based substrates. However, it will be understood by those having skill in the art that many embodiments of the present invention may employ any combination of a substrate that is non-absorbing or transparent to the emitted light and an index matched light emitting diode epitaxial layer. In some embodiments of the present invention, the refractive index of the substrate is greater than that of the diode. Accordingly, combinations can include an AlGaInP diode on a GaP substrate; an InGaAs diode on a GaAs substrate; an AlGaAs diode on a GaAs substrate; an SiC diode on an SiC substrate, an SiC diode on a sapphire (Al2O3) substrate; and/or a nitride-based diode on a gallium nitride, silicon carbide, aluminum nitride, zinc oxide and/or other substrate. Finally, it will be understood that although embodiments of the present invention are described herein with respect to light emitting diodes having an epitaxial region that includes therein a light emitting diode region, other embodiments of the present invention may be used with other semiconductor light emitting devices such as lasers, wherein an epitaxial region includes therein a light emitting region such as a laser diode region. Some embodiments of the present invention provide a metal stack with a passivation layer on its perimeter that defines a bonding region on LED devices that can be well suited for die attachment via soldering and/or thermosonic scrub bonding. Other embodiments of the present invention provide LED devices that can be flip chip mounted using soldering and/or thermosonic bonding, and that include a barrier layer that can reduce or eliminate unwanted degradation of the metal and/or semiconductor layers of the LED. Still other embodiments of the present invention can provide both the passivation layer and the barrier layer. Yet other embodiments of the present invention provide methods of fabricating these LED devices. Passivation layers according to some embodiments of the present invention can provide means for preventing a short circuit across the diode region. Moreover, barrier layers according to some embodiments of the present invention can provide means for reducing migration of tin and/or other undesired materials into the LED. In a conventional sapphire-based approach, an LED, also referred to as a chip or die, is attached to a submount with a clear epoxy. In the case of LEDs having conductive SiC substrates, a conducting silver filled epoxy is typically used to attach the LED and the submount to one another. Conventional nitride-based LEDs on SiC or sapphire substrates generally are packaged with the epitaxial side up and with the substrate bonded to the submount. Some embodiments of conventional SiC-based LEDs have an n-type conductive substrate and an epitaxial region on the substrate that includes one or more n-type epitaxial layers and one or more p-type epitaxial layers to define a diode region. A transparent ohmic contact may be formed on the p-type epitaxial LED surface. As discussed in U.S. patent application Ser. No. 10/057,821, corresponding to U.S. Publication No. US 2002/0123164 A1, referenced above, it may be beneficial to form a reflector layer over the thin transparent ohmic contact to improve light extraction from the device. The reflective layer can serve to spread electric current uniformly across the thin contact, and also to reflect light back into the substrate, away from the submount. Unfortunately, if Sn and/or other contaminants from a solder or thermosonic/thermocompression bond migrates from the bonding surface to the reflector layer, the reflector layer may become less reflective. Moreover, if the contaminants migrate beyond the reflector to the transparent ohmic contact, the transparent ohmic contact may develop a higher specific contact resistivity, thus increasing the forward voltage (VF) of the device. Both of these results may be characterized as degradation of the device. A reflective layer may comprise Ag and/or Al, and the thin transparent ohmic layer can comprise Pt, Pd, Ni, Ti, Au or a combination of these elements. Unfortunately, Sn readily forms alloys with Ag, Pt, Au and with numerous other metals used in semiconductor manufacturing. A first portion of a series of conductive layers (referred to herein as a “multilayer conductive stack”) that may be formed on the p-type surface of an LED according to some embodiments of the present invention comprises an ohmic layer, a reflector layer, and a barrier layer. In some embodiments, the barrier layer comprises a thin layer of titanium, titanium/tungsten (TiW) and/or titanium nitride/tungsten (TiNW). In other embodiments, the barrier layer comprises a first layer of titanium/tungsten and a second layer comprising nickel on the first layer. In still other embodiments, the barrier layer extends onto the sidewalls of the ohmic layer and the reflector layer and/or includes an alternating stack of a barrier metal layer and a second metal. In some embodiments of the present invention, this portion of the multilayer conductive stack and the top of the device are passivated with a passivation layer, such as an insulating layer to which a solder or eutectic die attach material will not wet. The passivation layer can be formed by conventional spin-on or deposition techniques such as Chemical Vapor Deposition (CVD) and/or reactive sputtering, and it can comprise an insulating oxide and/or nitride such as silicon dioxide and/or silicon nitride. In some embodiments of the present invention, an opening in the passivation layer is then formed with lateral dimensions (i.e. surface area) that are smaller than the lateral dimensions of the barrier layer such that only a portion of the surface of the barrier layer is exposed. Such an opening can be produced using conventional photolithography and etching techniques. An optional adhesion layer that may comprise Ti, is formed in the opening and a thick bonding layer that may comprise Au, Sn and/or AuSn also is formed. In other embodiments, an optional solder wetting layer is provided between the adhesion layer and the bonding layer. The solder wetting layer can provide an enhanced mechanical connection between the solder and the LED, which can increase the shear strength of the connection. In some embodiments of the present invention, the bonding layer can serve to protect the barrier layer if mechanical stress is to be applied to the multilayer conductive stack by a probe tip during electrical tests. Furthermore, in other embodiments of the present invention, the Au in the bonding layer can serve to protect the barrier layer from oxidation. In yet other embodiments of the present invention, AuSn may be employed in the bonding layer as a eutectic die attach material that may be used to bond an LED and a submount to one another via thermosonic or thermocompression bonding as an alternative to solder bonding. Multilayer conductive stacks according to some embodiments of the present invention can be well suited for solid state devices in that some embodiments of the present invention can provide a stack that is considerably thinner than may be achieved if a solder barrier is formed using Ni or NiV. In some embodiments of the present invention, a barrier layer comprising W, TiW and/or TiNW and/or W and Ni layers can be less than half of the thickness that may be used if only Ni were used as the barrier layer. This may be advantageous when considering the generally small lateral dimensions of solid state devices and when considering the potential difficulty associated with the use of conventional fabrication techniques if large topographical dimensions are present. The barrier layer also can provide a desired vertical barrier against Sn and/or other undesired migration. Passivation layers according to some embodiments of the invention can cover the entire epitaxial surface of the LED except for a reduced area opening that exposes the barrier layer, and can provide a dam to reduce or prevent Sn and/or other undesired migration into the reflective mirror layer or the ohmic contact, or down the edges of the metal stack. In the case of an LED having a conducting substrate, passivation layers according to some embodiments of the invention also can serve to keep the die-attach material from contacting the substrate which could produce undesired effects such as formation of a parasitic Schottky diode. Large area LEDs operating at high power levels may use packaging that has low thermal resistance to reduce or prevent degradation of the device performance. Epoxy based die attach materials may have high thermal resistance in comparison to metal die attach materials. In a flip-chip configuration, the p-n junction region of an LED is mounted extremely close to the heat sinking package, which can bypass the thermal resistance of the substrate. This may be used for large-area SiC-based LEDs in some embodiments of the present invention, despite the low thermal resistance of SiC. The metal-metal bond provided by some embodiments of the present invention also may be used in LEDs having sapphire substrates, due to the high thermal resistance of sapphire. Consequently, some embodiments of the present invention may be used for large area LEDs, which may benefit from employing a junction down (flip-chip) metal-metal die attach configuration. Other embodiments of the present invention may be used with small-area LEDs. Some embodiments of the present invention also may increase the permissible temperature range that the device can withstand during subsequent packaging, assembly and re-work/repair steps. Metal-metal bonds can be engineered for subsequent thermal cycles, for example, where the LED is mounted to a printed circuit board. If the LED die is attached to its submount with a AuSn thermosonic or thermocompression bond at 300° C. or by SnAg solder at 230° C., subsequent processing cycles using SnPb solder at 200° C. may not cause mechanical failure by reflowing the die attach bond. That is, subsequent processing at elevated temperatures may not cause the LED die to detach from the submount. In contrast, LEDs using epoxy based die attach methods may not withstand high thermal cycles. Moreover, clear epoxy can become discolored during thermal processing, resulting in unwanted light attenuation. Some embodiments of the present invention may also increase the shear strength of resulting bonds between the LED and the submount. Inclusion of a solder barrier layer which reduces or prevents tin and/or other unwanted materials from reaching the epitaxial layers of the device can preserve the adhesive strength of the metal-semiconductor interface and can result in a more robust, mechanically stable device. In particular, it has been found that embodiments that include a nickel solder wetting layer beneath a gold bonding layer may exhibit superior shear strength. The shear strength may also be maintained through thermal cycles during subsequent packaging, assembly and re-work/repair steps. In addition, some embodiments of the present invention may improve the thermal conductivity of the resulting device. This effect may be particularly apparent in so-called “power” or large area LEDs which may carry a substantially higher current than conventional LEDs. In such LEDs, some embodiments of the present invention can prevent or reduce “voiding”within the metallic layers. Voiding refers to the formation of physical voids or spaces within a metallic region. Some embodiments of the present invention may serve to maintain a tight grain structure within such metallic layers, thereby allowing the device to maintain a high thermal conductivity despite operation at high power levels with correspondingly high junction temperatures. Improved thermal conductivity also may help reduce degradation of encapsulant materials in which LEDs, and in particular power LEDs, are packaged. Such encapsulants are typically sensitive to heat and may yellow and become less transparent after expose to high temperatures for extended periods of time. By improving the thermal conductivity of the LED mount interface, less heat may be dissipated through the encapsulant, which can result in reduced degradation. FIG. 1 illustrates an LED device precursor 10 according to some embodiments of the present invention, comprising a substrate 20 having first and second opposing faces 20a and 20b, respectively, and an epitaxial region 22 formed on the first face 20a of the substrate 20. Substrate 20 may comprise silicon carbide, sapphire, aluminum nitride, gallium nitride or any other suitable conductive or non-conductive substrate material. In some embodiments of the present invention, the substrate 20 comprises conductively doped SiC. In some embodiments of the present invention, the substrate 20 is transparent to optical radiation in a predetermined wavelength range. In some embodiments of the present invention, epitaxial region 22 comprises a conductive buffer layer and a plurality of Group III-nitride epitaxial layers, at least some of which provide a diode region. The dimensions of the substrate, epitaxial layers and metal layers shown in FIGS. 1-10 are not drawn to scale but are exaggerated for illustrative purposes. A thin SiO2 and/or other layer (not shown) may optionally be formed, for example, by Plasma Enhanced Chemical Vapor Deposition (PECVD) on the surface of the epitaxial region 22 to protect it during subsequent processing and cleaning steps. Subsequent to deposition of the epitaxial region 22, the epitaxial region 22 is patterned as shown in FIG. 2 to form a plurality of mesas 30 each having sidewalls 30a, 30b. Although not illustrated in FIG. 2, the mesas 30 may extend into the substrate 20. Moreover, in some embodiments of the present invention, the mesas 30 may be formed by selective epitaxial growth through openings in a mask, rather than blanket epitaxial growth and etching. Still referring to FIG. 2, in some embodiments of the present invention, a layer of photoresist 24 and/or other material is formed on the surface of the precursor 10 and patterned to expose the surface of the mesas 30, thereby defining a first reduced area 30c on the surface of the mesas 30. If an optional SiO2 layer is present, it may be etched through the openings in the photoresist 24 to expose the first reduced area 30c on the epitaxial surface layer of the epitaxial region 22 in the mesa 30. A multilayer conductive stack 35 is then formed on the first reduced areas 30c of the mesas 30 using, for example, conventional lift-off techniques. As shown in FIG. 3, the multilayer conductive stack 35 includes an ohmic layer 32, a reflector layer 34 and a barrier layer 36. In some embodiments of the present invention, the ohmic layer 32 comprises platinum, but in other embodiments it may comprise palladium, nickel/gold, nickel oxide/gold, nickel oxide/platinum, titanium and/or titanium/gold. Other embodiments of ohmic layers are described in the above-referenced U.S. Publication No. US 2002/0123164 A1. If the ohmic layer 32 comprises Pt, it is about 25 Å thick in some embodiments of the present invention. The reflector layer 34 may comprise any suitable reflective metal, and may comprise Al or Ag. The reflector layer 34 is about 1000 Å thick in some embodiments of the present invention. Other embodiments of reflector layers are described in the above-referenced application Ser. No. 10/057,821, corresponding to U.S. Publication No. US 2002/0123164 A1. In some embodiments of the present invention, the barrier layer 36 can be a solder barrier layer to prevent solder metals such as tin from reacting with the reflector layer 34 and/or ohmic layer 32. The barrier layer 36 comprises W, TiW and/or TiN/W and is between about 500 Å and about 50,000 Å thick in some embodiments of the present invention, and is about 5000 Å thick in other embodiments of the present invention. In other embodiments of the invention, the barrier layer 36 may comprise TiW having a composition of about 5% Ti and about 95% W. Other embodiments of the barrier layer 36 that comprise tungsten or titanium/tungsten and that are between about 500 Å thick to about 3000 Å thick, may be used when a solder bonding operation (described below) is performed at a reflow temperature of less than about 210° C. For example, when eutectic gold/lead/tin solders are used at reflow temperatures of about 190° C. to about 210° C., a barrier layer comprising between about 500 Å and about 3000 Å of titanium/tungsten may be used, according to some embodiments of the present invention. In other embodiments of the present invention, higher reflow temperatures may be used to accommodate other solders, such as solders comprising tin, silver and antimony, that have a reflow temperature of about 220° C. to about 260° C. One example of these solders is a Kester brand R276AC silver-tin solder paste that is about 96.5% tin and about 3.5% silver. Accordingly, in some embodiments of the present invention, the barrier layer 36 comprises a first layer of tungsten or titanium/tungsten 36a that is about 5000 Å thick, and a second layer 36b comprising nickel that is about 2000 Å thick, on the first layer, 36a. It has been found that some of these embodiments of the present invention can withstand temperatures of between about 325° and about 350° C., for about five minutes, without substantially increasing the forward voltage (VF) or reduce the light output of the LED. Thus, in some embodiments of the present invention, a multilayer barrier layer 36 comprising a layer of tungsten or titanium/tungsten 36a and a layer of nickel 36b is used with solders that have a reflow temperature of more than about 200° C. In other embodiments of the present invention, these multilayer barrier layers may be used with solders that have a reflow temperature of more than about 250° C. In some embodiments of the present invention, tungsten, silver and platinum are deposited, for example, using an e-beam technique. TiW may be deposited using an e-beam technique, but in other embodiments of the present invention, Ti and W are simultaneously sputter deposited. In addition, the TiW may be sputter deposited in the presence of nitrogen to form a TiN/TiW layer that also forms a barrier to Sn diffusion, in other embodiments of the present invention. In yet other embodiments of the present invention, the barrier layer 36 may consist essentially of nickel or NiV. In other embodiments of the present invention, the barrier layer 36 may comprise a 2500 Å nickel solder barrier covered completely with a layer of gold between about 500 Å and 10,000 Å thick. The gold layer can prevent the nickel layer from oxidizing. However, the use of a nickel barrier layer may result in unacceptably high degradation of optical and electrical performance at elevated temperature and current levels due to tin migration. Moreover, thicker films of nickel may be difficult to use since the film stress may be high. This may create concern with respect to delamination of the nickel from the adjacent reflective and/or ohmic layers. Moreover, the presence of Au at the edges of the barrier layer may create a path for Sn to migrate down and around the edges of the barrier. Referring now to FIG. 4, in some embodiments of the present invention, a passivation layer 40 is deposited or otherwise formed on the first (or epitaxial-side) surface 20a of device precursor 10. In some embodiments of the present invention, passivation layer 40 may comprise SiO2 and/or SiN (which may be deposited in stoichiometric or non-stoichiometric amounts) and may be deposited by conventional techniques such as PECVD and/or reactive sputtering. The passivation layer 40 is about 1500 Å thick in some embodiments of the present invention. As also shown in FIG. 4, this blanket deposition also forms the passivation layer on the sidewalls of the mesas 30 and the multilayer conductive stack 35, and on the exposed surface of the barrier layer 36. Referring now to FIG. 5, the passivation layer 40 is patterned with an etch mask (such as a photoresist) to provide a first patterned passivation layer 40a and to selectively reveal a second reduced area portion 36c of the surface of barrier layer 36. In other embodiments of the present invention, a lift off technique may be used to expose the second reduced area portion 36c of the surface of the barrier layer 36. In still other embodiments of the present invention, selective deposition of the passivation layer 40a may be used so that a separate patterning step need not be used. Still referring to FIG. 5, an optional adhesion layer 55 comprising, for example, Ti is then deposited on the second reduced area 36c of the barrier layer 36 and a bonding layer 60 is deposited on the adhesion layer 55. These depositions may be performed using the patterned passivation layer 40a as a mask and/or using lift-off techniques. The adhesion layer 55 is about 1000 Å thick in some embodiments of the present invention. The bonding layer 60 may comprise Au, Sn and/or AuSn and is about 1000 Å thick in some embodiments. The bonding layer 60 may be up to about 1 μm thick (if Au) or about 1.7 μm thick (if AuSn) in some embodiments of the present invention. However, in some embodiments, use of a layer of Au that is thicker than about 1000 Å may lead to inconsistent solder reflow processing or Au embrittlement of the solder attachment, which may result in low shear strength. As shown, the patterned passivation layer 40a also is on the sidewalls of the adhesion layer 55 and the bonding layer, according to some embodiments of the present invention. In other embodiments, the patterned passivation layer 40a does not extend on the sidewalls of the adhesion layer 55 and the bonding layer 60. In these embodiments, the passivation layer may extend on the sidewalls of the conductive stack 35. According to other embodiments of the present invention, the bonding layer 60 extends away from the multilayer conductive stack 35, to beyond the patterned passivation layer 40a. In yet other embodiments, the bonding layer 60 does not extend to beyond the outer surface of the patterned passivation layer 40a. For devices formed on conductive substrates, ohmic contacts and a wire bond pad (not shown) are formed on the second substrate face 20b opposite the epitaxial region to form a vertically-conductive device. Many such embodiments are described in application Ser. No. 10/057,821, corresponding to U.S. Publication No. US 2002/0123164 A1. For devices formed on non-conductive substrates, ohmic contacts and metal bonding layers (not shown) may be formed on an n-type epitaxial region of the device to form a horizontally-conductive device. Many such embodiments also are shown in application Ser. No. 10/057,821, corresponding to U.S. Publication No. US 2002/0123164 A1. Referring now to FIG. 6, the precursor 10 is diced into individual light emitting diodes 100. FIG. 6 also shows that LEDs 100 may be sawed such that they have a beveled sidewall configuration 70 to increase light extraction. Many other embodiments of substrate shaping are described in application Ser. No. 10/057,821, corresponding to U.S. Publication No. US 2002/0123164 A1. Accordingly, FIG. 6 illustrates light emitting diodes 100 according to some embodiments of the present invention that include a substrate 20, an epitaxial region (referred to previously as a mesa) 30 on the substrate 20 that includes therein a diode region, a multilayer conductive stack 35 on the epitaxial region 30 opposite the substrate 20, and a passivation layer 40b that extends at least partially on the multilayer conductive stack 35 opposite the epitaxial region 30, to define a reduced area bonding region 36c on the multilayer conductive stack 35 opposite the epitaxial region 30. In some embodiments, the passivation layer 40b also extends across the multilayer conductive stack 35, across the epitaxial region 30, and onto the first substrate face 20a. As also shown in FIG. 6, in some embodiments of the present invention, the multilayer conductive stack 35 and the epitaxial region 30 both include sidewalls, and the passivation layer 40b extends on the sidewalls of the multilayer conductive stack 35 and of the epitaxial region 30. As also shown in FIG. 6, a bonding layer 60 is provided on the bonding region 36c. The bonding layer 60 also includes a bonding layer sidewall, and the passivation layer 40b may or may not extend onto the bonding layer sidewall. Finally, an adhesion layer 55 may be provided between the multilayer conductive stack 35 and the bonding layer 60, and the passivation layer 40b also may or may not extend onto the sidewall of the adhesion layer 55 and/or the bonding layer 60. Still referring to FIG. 6, in some embodiments of the present invention, the substrate 20 includes a first face 20a adjacent the epitaxial region 30 and a second face 20b opposite the epitaxial region. As illustrated in FIG. 6, the bonding layer 60 has smaller surface area than the multilayer conductive stack 35 and the multilayer conductive stack 35 has smaller surface area than the epitaxial region 30. The epitaxial region 30 has smaller surface area than the first face 20a. The second face 20b also has smaller surface area than the first face 20a. FIG. 6 also illustrates light emitting diodes according to some embodiments of the invention that include a substrate 20 having first and second opposing faces 20a and 20b, respectively, the second face 20b having smaller surface area than the first face. An epitaxial region 30 is on the first face 20a, and includes therein a diode region. An ohmic layer 32 is on the epitaxial region 30 opposite the substrate 20. A reflector layer 34 is on the ohmic layer 32 opposite the epitaxial region 30. A barrier layer 36 is on the reflector layer 34 opposite the ohmic layer 32. An adhesion layer 55 is on the barrier layer 36 opposite the reflector layer 34. Finally, a bonding layer 60 is on the adhesion layer 55 opposite the barrier layer 36. As also shown in FIG. 6, in some embodiments of the present invention, the barrier layer 36 comprises tungsten, titanium/tungsten and/or titanium nitride/tungsten. In other embodiments of the present invention, the tin barrier layer 36 comprises a first layer 36a comprising tungsten and a second layer 36b comprising nickel on the first layer 36a comprising tungsten. As also shown in FIG. 6, in some embodiments of the present invention, the epitaxial region 30 has smaller surface area than the first face 20a. The barrier layer 36, the reflector layer 34 and the ohmic layer 32 have same surface area, that surface area being less than that of the epitaxial region 30. The adhesion layer 55 and the bonding layer 60 have same surface area, that surface area being smaller than that of the barrier layer 36, the reflector layer 34 and the ohmic layer 32. Finally, as also shown in FIG. 6, in some embodiments of the invention, the epitaxial region 30, the ohmic layer 32, the reflector layer 34, the barrier layer 36, the adhesion layer 55 and the bonding layer 60 each include a sidewall and the light emitting diode 100 further includes a passivation layer 40b on the sidewalls of the epitaxial region 30, the ohmic layer 32, the reflector layer 34 and the barrier layer 36. The passivation layer also may or may not extend onto the sidewalls of the adhesion layer 55 and/or the bonding layer 60. The passivation layer 40b also may extend on the first face 20a of the substrate 20. FIG. 7 illustrates other embodiments of the present invention in which the bonding layer 60 comprises a solder wetting layer 62 and a wetting passivation layer 64. In some embodiments, the solder wetting layer 62 comprises nickel and is about 2000 Å thick. In some embodiments, the wetting passivation layer 64 comprises Au and is about 500 Å thick. Use of the nickel solder wetting layer 62 can provide an enhanced mechanical bond to the solder, which can increase the shear strength of the connection and can reduce the possibility of mechanical failure, according to some embodiments of the invention. FIG. 8 illustrates other embodiments of the present invention in which the bonding layer 60 and optional adhesion layer 55 do not extend beyond the outer edge 40c of the passivation layer 40b. This configuration may be used when solder bonding is used to mount the LED to a lead frame, according to some embodiments of the invention. FIGS. 1-8 also illustrate methods of fabricating a plurality of light emitting diodes according to some embodiments of the present invention. These methods comprise epitaxially forming a plurality of spaced apart mesa regions 30 on a substrate 20, the mesa regions including therein a diode region (FIG. 2). A first reduced area region 30c is defined on the mesa regions (FIG. 2). A multilayer conductive stack 35 that includes a barrier layer, is formed on the first reduced area regions 30c of the mesa regions 30 (FIG. 3). A passivation layer 40a is formed on the substrate 20 between the mesa regions 30, on exposed portions of the mesa regions and on exposed portions of the multilayer stack 35, the passivation layer 40a defining a second reduced area region 36c on the multilayer conductive stack 35 (FIGS. 4 and 5). A bonding layer 60 then is formed on the second reduced area regions 36c of the multilayer conductive stacks 35 (FIG. 5). The substrate 20 is diced between the mesas 30 to produce the plurality of light emitting diodes 100 (FIG. 6). Referring now to FIGS. 9 and 10, once the LED 100 has been diced, the LED and a conductive submount 75 are attached to one another as illustrated in FIGS. 9 and 10. FIG. 9 illustrates embodiments of the present invention in which the LED 100 is mounted in a “flip-chip” configuration with the epitaxial side down, via thermosonic and/or thermocompression bonding. That is, instead of using an epoxy or a solder to form a mechanical connection or bond between the LED 100 and the submount 75, the bonding layer 60 of LED 100 is thermosonically or thermocompressively bonded directly to the submount 75 as described, for example, in U.S. Provisional Application Ser. No. 60/307,234 and U.S. Publication No. US 2003/0042507 A1. In some embodiments of thermosonic or thermocompression bonding according to some embodiments of the present invention, the LED chip 100 is placed into mechanical contact with the submount and subjected to mechanical and/or sonic stimulation at a temperature greater than the eutectic temperature of the bonding metal. The bonding metal thus forms a bond with the metallic submount, which provides an electromechanical connection between the LED and the submount. In embodiments of the present invention in which the bonding layer 60 has an Au/Sn relative composition of about 80%/20%, the temperature used for thermosonic bonding may be approximately 300° C. The presence of the barrier layer 36 and/or the passivation layer 40b can reduce or prevent unwanted interaction between metals in the bonding layer 60 with the reflective layer 34 and/or the ohmic layer 32. The barrier layer 36 and/or the passivation layer 40 may also serve to retard or inhibit unwanted migration of metal along the edge of the metal stack 35. In other embodiments of the present invention, the LED 100 may be mounted on the submount 75 using a metal solder 80 such as SnAg, SnPb and/or other solders as illustrated in FIG. 10. The passivation layer 40b can reduce or prevent Sn from solder 80 from migrating to (and thereby potentially degrading) the reflective layer 34 and/or ohmic layer 32. The passivation layer 40b also can reduce or prevent conductive solder 80 from contacting the substrate 20 and mesa sidewalls, which may otherwise result in the formation of unwanted parasitic Schottky contacts to n-type regions of the device 100. Other bonding techniques that may be used, according to other embodiments of the present invention, are disclosed in the above-cited Provisional Application Ser. No. 60/307,311 and U.S. Publication No. 2003/0045015 A1. Test Results The following test results are illustrative and shall not be construed as limiting the scope of the present invention. FIGS. 11A-11D graphically illustrate test results for a 2500 Å Ni solder barrier while FIGS. 12A-12D graphically illustrate results for a 5000 Å TiW barrier. In a first test, the high temperature operating life (HTOL) of a number of LED samples was measured. In this test, twenty LEDs were fabricated with TiW solder barriers 36, SiN passivation layers 40b and gold bonding layers 60. Twenty LEDs also were fabricated with the same structure except that they used an Ni solder barrier. The devices were mounted on silver-plated 5 mm radial lead frames via solder bonding. The devices were then operated at a forward current of 20 mA while being maintained at a temperature of 85° C. Optical output power and VF were measured after 24, 168, 336, 504, 672, 864 and 1008 hours. As shown in FIGS. 11A and 12A, the devices with the Ni barrier exhibited larger degradation in light output, compared to the devices with the TiW barrier. Moreover, VF increased more in the Ni barrier devices (FIG. 11B) than in the TiW barrier devices (FIG. 12B). In a second test, twenty LEDs were fabricated with TiW solder barriers 36, SiN passivation layers 40b and gold bonding layers 60, and twenty LEDs were fabricated with the same structure except that they used the Ni barrier. The devices were mounted as described above in reference to the HTOL tests and operated at a pulsed forward current of 70 mA (25% duty cycle at 4 kHz) for a period of 504 hours while being maintained at a temperature of 85° C. and a relative humidity of 85%. Optical output power and VF were measured after 24, 168, 336, 504, 672, 864 and 1008 hours. As shown in FIGS. 11C and 12C, larger degradation in light output occurred with the Ni barrier and, as shown in FIGS. 11D and 12D, a larger increase in VF occurred with the Ni barrier. Barrier Layer/Sublayer Structures and Fabrication Methods It is desirable to limit migration of metal from the reflector layer 34, also referred to as a mirror 34, since such metal can short circuit the pn junction of the device if it comes into contact with the mesa 30. This is particularly true when the mirror 34 comprises silver, which tends to migrate easily at relatively low temperatures. See, for example, the textbook entitled Corrosion and Environmental Degradation, Vol. II, to Schütze, 2000, pp. 451-452. In the presence of surface moisture and an electric field, silver ions can form at positive (anodic) metallizations due to oxidation and/or corrosion. When the silver ions migrate to negative (cathodic) metallizations, they can plate out in the form of a dendrite (i.e., a branching structure). The dendrite may eventually bridge the gap between the anode and cathode of the LED and cause a short circuit. In order to limit migration of the mirror metal 34 to the mesa 30, according to some embodiments of the invention, it may be desirable to extend the barrier layer 36 over the sidewalls of the reflector layer 34, as illustrated in FIG. 13. This may be accomplished by performing an additional photolithography step to form the ohmic contact layer 32 and the reflector layer 34 to have a reduced width compared to the width of barrier layer 36, and/or using other conventional techniques. Thus, when barrier layer 36 is formed, e.g., deposited, it may contact the sidewalls of reflector layer 34 and ohmic contact 32 as well as a portion of the surface of mesa 30 surrounding the ohmic contact 32 and reflector layer 34. If the barrier layer 36 is formed in such a way as to cover the sidewalls of reflector layer 34 as illustrated in FIG. 13, it is possible for cracks in the barrier layer to form near the sidewalls of the reflector layer 34. Such cracks may provide a migration path for silver from the reflector layer 34 to escape and potentially migrate to the mesa 30. The formation of cracks is illustrated in FIG. 14, which shows a mesa 30 on which a thin ohmic contact layer 32 has been formed. A silver reflector layer 34 is formed on the ohmic contact layer 32, and the entire structure is covered with a layer 36 of a barrier metal such as TiW. As can be seen in FIG. 14, when the TiW barrier metal layer 36 is deposited, it forms vertically oriented grains 47 separated by grain boundaries 49. Misalignment of the grains 47 at the corners of the reflector layer 34 may cause cracks 51 to form, which may provide a migration path for metal from the reflector layer 34 to escape and potentially migrate to the mesa 30. In order to reduce or avoid the formation of cracks 51, a barrier layer 36 according to some embodiments of the present invention may comprise a plurality of alternating sublayers of a barrier metal 36A such as TiW and a second metal 36B such as platinum, as illustrated in FIG. 15. Suitable metals for second metal 36B are Pt, Ti, Ni and/or other metals. Metal 36B should not be susceptible to migration in the LED structure and should have a melting point higher than any of the processing steps subsequently used in the fabrication of the LED (in some embodiments at least about 200° C.). In one embodiment, barrier layer 36 comprises alternating sublayers of about 1000 Å of TiW and about 500 Å of platinum repeated at least two times with the top and bottom sublayers of the stack both comprising TiW. In other words, the plurality of first and second alternating sublayers define first and second outer sublayers that comprise the first sublayer. In addition, the second (final) outer layer of TiW in the stack may be made approximately 5000 Å thick to act as a solder barrier. In one embodiment, the TiW/Pt layer stacks are repeated six times with the final (terminating) layer of TiW being about 5000 Å thick. Many other thicknesses of the barrier metal 36A and the second metal 36B may be used in other embodiments of the invention. In general, barrier metal 36A should be sufficiently thin to reduce or prevent cracking, but sufficiently thick to provide an effective barrier, while the second metal 36B should be sufficiently thin so as not to degrade the resistance of the contact, but sufficiently thick to prevent cracks in the barrier metal layer 36A from propagating across the second barrier layer. As illustrated in FIG. 15, the grain boundaries 49 of successive layers of TiW do not necessarily align vertically, thereby inhibiting the formation of long cracks through the barrier layer 36 that may otherwise provide a migration path for the reflector metal. In that regard, the successive TiW layers may form a pattern that generally resembles a brick wall with stacks of offset grains in each layer. This effect is illustrated in FIGS. 16 and 17, which are 40,000×SEM images of a metal stack fabricated in accordance with the embodiments illustrated in FIGS. 14 and 15, respectively. In the structure shown in FIG. 16, a TiW barrier layer 36 is deposited as a single layer over a reflector 34 and ohmic contact 32. Vertical grain boundaries 49 are visible within the barrier layer 36. In addition, a crack 51 is visible extending from the edge of the reflector layer 34 to the surface of the barrier layer. In contrast, in the structure shown in FIG. 17, the barrier layer 36 comprises a plurality of alternating layers of TiW 36A and platinum 36B. The grain boundaries 49 in the alternating layers of TiW 36A can be clearly seen to form a brick wall pattern over the reflector layer 34 and mesa 30. In contrast to the structure shown in FIG. 16, no cracking is evident in the barrier layer 36. In the drawings and specification, there have been disclosed embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Light emitting diodes are widely used in consumer and commercial applications. As is well known to those having skill in the art, a light emitting diode generally includes a diode region on a microelectronic substrate. The microelectronic substrate may comprise, for example, gallium arsenide, gallium phosphide, alloys thereof, silicon carbide and/or sapphire. Continued developments in LEDs have resulted in highly efficient and mechanically robust light sources that can cover the visible spectrum and beyond. These attributes, coupled with the potentially long service life of solid state devices, may enable a variety of new display applications, and may place LEDs in a position to compete with the well entrenched incandescent and fluorescent lamps. Gallium Nitride (GaN)-based LEDs typically comprise an insulating or semiconducting substrate such as silicon carbide (SiC) or sapphire on which a plurality of GaN-based epitaxial layers are deposited. The epitaxial layers comprise an active or diode region having a p-n junction which emits light when energized. LEDs may be mounted substrate side down onto a submount, also called a package or lead frame (hereinafter referred to as a “submount”). In contrast, flip-chip mounting of light emitting diodes involves mounting the LED onto the submount with the substrate side facing up (i.e. away from the submount). Light may be extracted and emitted through the substrate. Flip chip mounting may be an especially desirable technique for mounting SiC-based LEDs. In particular, since SiC has a higher index of refraction than GaN, light generated in the active or diode region generally does not totally internally reflect (i.e. reflect back into the GaN-based layers) at the GaN/SiC interface. Flip chip mounting of SiC-based LEDs also can improve the effect of certain substrate-shaping techniques known in the art. Flip chip packaging of SiC LEDs may have other benefits, such as improved heat dissipation, which may be desirable depending on the particular application for the LED. Because of the high index of refraction of SiC, light passing through an SiC substrate tends to be totally internally reflected into the substrate at the surface of the substrate unless the light strikes the surface at a fairly low angle of incidence (i.e. fairly close to normal). The critical angle for total internal reflection generally depends on the material with which SiC forms an interface. It is possible to increase the light output from an SiC-based LED by shaping the SiC substrate in a manner that limits total internal reflection by causing more rays to strike the surface of the SiC at low angles of incidence. A number of such shaping techniques and resulting devices are taught in U.S. patent application Ser. No. 10/057,821 to Slater et al, corresponding to U.S. Publication No. US 2002/0123164 A1, published Sep. 5, 2002, entitled Light Emitting Diodes Including Modifications for Light Extraction and Manufacturing Methods Therefor. One potential problem with flip-chip mounting is that when an LED is mounted on a submount using conventional techniques, a conductive die attach material such as silver epoxy is deposited on the LED and/or on the package, and the LED and the submount are pressed together. This can cause the viscous conductive die attach material to squeeze out and make contact with the N-type substrate and/or layers in the device, thereby forming a Schottky diode connection that can short-circuit the p-n junction in the active region. Metal-metal bonds formed by soldering, thermosonic scrubbing and/or thermocompression bonding are alternative attach techniques. However, tin (Sn) is a component of most types of solder, and migration of Sn from the bonded surface into the device can cause unwanted degradation of the device. Such migration can interfere with metal-semiconductor interfaces such as ohmic contacts and/or the function of metal-metal interfaces such as reflective interfaces that serve as mirrors. | <SOH> SUMMARY OF THE INVENTION <EOH>Semiconductor light emitting devices such as light emitting diodes, according to some embodiments of the present invention, include a substrate, an epitaxial region on the substrate that includes therein a light emitting region such as a light emitting diode region, and a multilayer conductive stack comprising a reflector layer including a reflector layer sidewall, on the epitaxial region. A barrier layer is provided on the reflector layer and extending on the reflector layer sidewall. In other embodiments, the multilayer conductive stack further comprises an ohmic layer, including an ohmic layer sidewall, between the reflector and the epitaxial region. The barrier layer further extends on the ohmic layer sidewall. In still other embodiments of the present invention, the barrier layer further extends onto the epitaxial region outside the multilayer conductive stack. In other embodiments of the present invention, the barrier layer comprises a plurality of first and second alternating sublayers. In some embodiments, the first sublayers include grain boundaries therein and the second sublayers are substantially free of grain boundaries. In other embodiments, the first sublayers include grain boundaries that are arranged such that the grain boundaries define an offset brick wall structure of the first sublayers. In still other embodiments, the first sublayers comprise titanium tungsten and the second sublayers comprise platinum, titanium and/or nickel. In some embodiments, the first sublayers are configured to reduce migration of metal from the reflector layer, and the second sublayers are configured to prevent at least some grain boundaries in the first sublayers for propagating thereacross. In other embodiments, the plurality of first and second alternating sublayers define first and second outer sublayers that comprise the first sublayer. In still other embodiments, the second outer sublayer is thicker than the first outer sublayer. Other embodiments of the invention provide methods of reducing migration of metal from the reflective layer into the epitaxial region of a semiconductor light emitting device, by forming a barrier layer on the reflector layer that extends on the reflector layer sidewall. In other embodiments, the barrier layer is formed to extend on the ohmic layer sidewall. In still other embodiments, the barrier layer extends onto the epitaxial region outside the multilayer conductive stack. Still other embodiments of the present invention form the barrier layer as a plurality of alternating first and second sublayers, which can reduce cracking of the barrier layer adjacent the reflector layer sidewall. The first and second sublayers can define an offset brick wall structure that can terminate with a first sublayer, to define an outer sublayer, wherein the second sublayers are thinner than the first sublayers and the outer sublayer is thicker than the first sublayers. | 20050120 | 20070501 | 20050908 | 72911.0 | 3 | TRAN, MINH LOAN | LIGHT EMITTING DIODES INCLUDING BARRIER LAYERS/SUBLAYERS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,039,625 | ACCEPTED | Vapor compression air conditioning or refrigeration system cleaning compositions and methods | The present invention relates to compositions that are suitable for removing or reducing residue from a vapor compression air conditioning or refrigeration system consisting essentially of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester, and methods of using the composition. | 1. A composition for removing residue from a vapor compression air conditioning or refrigeration system, said composition consisting essentially of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and a polyol ester. 2. The composition of claim 1 wherein said polyol ester is a reaction product of a carboxylic acid and at least one polyol selected from the group consisting of neopentyl glycol, glycerol, trimethylol propane and pentaerythritol. 3. The composition of claim 1 wherein said polyol ester is a neopentyl glycol ester represented by the formula C(CH3)2(CH2OC(O)R1)2, wherein each R1 is independently selected from C6-12 saturated, cyclic, straight chain or branched, hydrocarbon radicals. 4. The composition of claim 3 wherein each R1 is a saturated, branched C7 hydrocarbon radical. 5. The composition of claim 4 wherein each R1 is a 1-ethyl-pentyl radical. 6. The composition of claim 1 consisting essentially of from about 5 to about 25 weight percent 1,1,1,2,2,3,4,5,5,5-decafluoropentane and from about 75 to about 95 weight percent polyol ester. 7. The composition of claim 1 consisting essentially of about 15 weight percent 1,1,1,2,2,3,4,5,5,5-decafluoropentane and about 85 weight percent polyol ester. 8. A composition for removing residue from a vapor compression air conditioning or refrigeration system, said composition consisting essentially of about 15 weight percent 1,1,1,2,2,3,4,5,5,5-decafluoropentane and about 85 weight percent neopentyl glycol di-2-ethylhexanoate. 9. A method for removing or reducing residue in a vapor compression air conditioning or refrigeration system, said method comprising: removing essentially all refrigerant and lubricant from said vapor compression system, contacting said vapor compression system with a composition of any of claims 1-8 for a period of time sufficient to reduce the amount of residue in said system, and removing said composition from said system. 10. A method for cleaning a component of a vapor compression air conditioning or refrigeration system comprising the steps of: flushing the component with a composition of any of claims 1-8; and removing said composition from said component. | CROSS REFERENCE TO RELATED APPLICATION This application claims the priority benefit of U.S. Provisional Application 60/538,009, filed Jan. 20, 2004. FIELD OF THE INVENTION The present invention relates to compositions and methods for cleaning lubricated vapor compression systems. BACKGROUND OF THE INVENTION There is a need to clean lubricated vapor compression systems and their components during manufacture and service. Vapor compression air conditioning and refrigeration systems are well known in the art. They are used in a wide variety of applications such as heating, air conditioning, and refrigeration. By compressing and expanding a heat transfer agent or refrigerant, these systems absorb and release heat according to the needs of a particular application. Common components of a vapor compression system include: vapor or gas compressors; liquid pumps; heat-transfer equipment such as gas coolers, intercoolers, aftercoolers, heat exchangers, economizers; vapor compressors, such as reciprocating piston compressors, rotating screw compressors, centrifugal compressors, and scroll compressors; evaporators; liquid coolers and receivers; expanders; control valves and pressure-drop throttling devices such as capillaries and orifice tubes; refrigerant-mixture separating chambers; and connecting piping and insulation. These components are typically fabricated from aluminum, copper, brass, steel, various plastics and conventional gasket and O-ring materials. Since vapor compression systems have sliding, rotating or other moving components, most require the use of a lubricant which is mixed with the refrigerant. There is a need from time to time to clean such systems and their components by removing the lubricants as well as other contaminants and debris from their surfaces. Such a need arises, for example, during the retrofit of a chlorofluorocarbon (CFC) to a hydrochlorofluorocarbon (HCFC) or hydrofluorocarbon (HFC), or retrofit of a HCFC refrigerant to a HFC refrigerant, and during service, especially after a catastrophic event such as compressor burnout or mechanical failure. Until recently, CFCs, such as trichloromethane (R-11), and HCFCs, such as 1,1-dichloro-1-fluoroethane (HCFC-141 b), were used as cleaning agents for such systems. Although effective, CFCs and HCFCs are now considered environmentally unacceptable because they are believed to contribute to the depletion of the stratospheric ozone layer. As the use of CFCs and HCFCs is reduced and ultimately phased out, new cleaning agents are needed that not only perform well, but also pose no danger to the ozone layer. A number of environmentally acceptable solvents have been proposed, but their use has been met with limited success. For example, organic solvents, such as hexane, have good cleaning properties and do not deplete the ozone layer, but they are flammable. Aqueous-based cleaning compositions have zero ozone depletion potential and are non-flammable, but they tend to be difficult to remove from the cleaned surfaces due to their relatively low volatility and the presence therein of additives that leave a residue. Additionally, aqueous-based cleaning compositions are often inadequate for cleaning typical organic soils that are present in vapor compression systems. Terpene-based solvents, like aqueous-based cleaning compositions, are difficult to remove from the system. Therefore, a need exists for the identification of environmentally-acceptable cleaning agents that effectively clean vapor compression systems. The present invention fulfills this need. BRIEF SUMMARY OF THE INVENTION Disclosed herein is a composition for reducing and removing residue from a vapor compression air conditioning or refrigeration system, said composition consisting essentially of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester, wherein said polyol ester is selected from esters of neopentyl glycol, glycerol, trimethylol propane, pentaerythritol and carboxylic acids represented by the formula HOC(O)R1, where R1 is a C6-12 saturated, cyclic, straight chain or branched hydrocarbon radical. Also disclosed is a method for reducing residue in a vapor compression air conditioning or refrigeration system, said method comprising: removing substantially all refrigerant and lubricant from said vapor compression air conditioning or refrigeration system, contacting said vapor compression air conditioning or refrigeration system with the composition of the present invention for a period of time sufficient to reduce the amount of residue in said system, and removing said composition from said system. The present invention further comprises a method for cleaning a component of a vapor compression system, said method comprising the steps of: flushing the component with composition of the present invention; and removing said composition from said component. DETAILED DESCRIPTION OF THE INVENTION Vapor compression air conditioning or refrigeration system as used herein refers to a complete system, groupings of components of a system, individual components of a system, or portions of individual components of a system. The present composition and method have utility in removing residue from common compression refrigeration systems including components such as: vapor or gas compressors; liquid pumps; heat-transfer equipment such as gas coolers, intercoolers, aftercoolers, heat exchangers, economizers; vapor compressors, such as reciprocating piston compressors, rotating screw compressors, centrifugal compressors, and scroll compressors; evaporators; liquid coolers and receivers; expanders; control valves and pressure-drop throttling devices such as capillaries and orifice tubes; refrigerant-mixture separating chambers; and connecting piping and insulation. These components are typically fabricated from aluminum, copper, brass, steel, various plastics and conventional gasket and O-ring materials. Residue removed by the present composition and method may include compressor lubricant and particulates, including decomposed lubricant, metal (for example aluminum, copper, brass, steel particulates from system components), rubbers and plastics (for example, from system hoses and O-rings). The invention disclosed herein is a flushing or cleaning composition for removing residue from a vapor compression air conditioning or refrigeration system, said composition consisting essentially of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and a polyol ester. The composition may be used as a flushing composition with a flush kit, in a closed-loop system, or in any suitable manner to achieve flushing of a component with the inventive composition. 1,1,1,2,2,3,4,5,5,5-decafluoropentane (HFC-43-10mee, CF3CF2CHFCHFCF3) is a commercial product of E. I. du Pont de Nemours and Company, Wilmington, Del., USA. Polyol esters of the present invention are available commercially from Hatco Co., New Jersey, USA. Polyol esters of the present invention are reaction products of a carboxylic acid and at least one polyol selected from neopentyl glycol, glycerol, trimethylol propane and pentaerythritol. Preferred of the polyols is neopentyl glycol. Carboxylic acids that are used to produce the polyol esters of the present invention are represented by the formula HOC(O)R1, where R1 is a C6-12 saturated, cyclic, straight chain or branched, hydrocarbon radical. Examples of carboxylic acids include 2,2-dimethylpentanoic acid, 2-ethylpentanoic acid, 3-ethylpentanoic acid, 2-methylhexanoic acid, 3-methylhexanoic acid, 4-methylhexanoic acid, 5-methylhexanoic acid, cyclohexanecarboxylic acid, cyclopentylacetic acid, 2-ethylhexanoic acid, 3,5-dimethylhexanoic acid, 2,2-dimethylhexanoic acid, 2-methylheptanoic acid, 3-methylheptanoic acid, 4-methylheptanoic acid, 2-propylpentanoic acid, 3,4-dimethylhexanoic acid, cyclohexylacetic acid, 3-cyclopentylpropionic acid, 2,2-dimethylheptanoic acid, 3,5,5-trimethylhexanoic acid, 2-methyloctanoic acid, 2-ethylheptanoic acid, 3-methyloctanoic acid, 2-ethyl-2,3,3-trimethylbutyric acid, 2,2,4,4-tetramethylpentanoic acid and 2,2-diisopropylpropionic acid, with preference given to 2-methylhexanoic acid, 2-ethylhexanoic acid, 3,5-dimethylhexanoic acid and 3,5,5-trimethylhexanoic acid. Preferred of the carboxylic acids is 2-ethylhexanoic acid. Preferred polyol esters of the present invention are neopentyl glycol esters that are represented by C(CH3)2(CH2OC(O)R1)2, wherein each R1 is independently selected from C6-12 saturated, cyclic, straight chain or branched, hydrocarbon radicals. R1 is preferrably a saturated, branched C7 hydrocarbon radical and most preferrably the 1-ethylpentyl radical. A preferred neopentyl glycol ester is neopentyl glycol di-2-ethylhexanoate (C(CH3)2(CH2OC(O)CH(C2H5)(CH2)3CH3)2). The amount of 1,1,1,2,2,3,4,5,5,5-decafluoropentane in the present 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester composition is from about 5 to about 25 weight percent, preferably about 15 weight percent, with the remainder being polyol ester, based on the total weight of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester. A preferred composition of the present invention consists essentially of about 15 weight percent 1,1,1,2,2,3,4,5,5,5-decafluoropentane and about 85 weight percent neopentyl glycol di-2-ethylhexanoate. The compositions of the present invention is prepared by adding the weight percentage of each of component to a common vessel, optionally with agitation. The combination yields the composition of the present invention. The present invention further comprises a method for reducing or removing residue in a vapor compression refrigeration system comprising: removing essentially all refrigerant and lubricant from said vapor compression refrigeration system, contacting said vapor compression refrigeration system with an aforementioned 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester composition for a period of time sufficient to reduce the amount of residue in said system, and removing said composition from said system. The present invention further comprises a method for cleaning a component of a vapor compression system comprising the steps of: flushing the component with an aforementioned 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester composition, and removing said composition from said component. In use, a composition of the present invention may be first applied to the surface of a component of the lubricated vapor compression system. The application techniques are known in the art, and include exposing the composition in the liquid form to the component or system. Next, the cleaning composition is removed from the component or system by the use of pressurized air or nitrogen. Suitable cleaning techniques include degreasing a particular component or flushing the system. Degreasing particular components can be performed in an open or closed degreasers. Such cleaning apparatus is well known in the art. Various procedures used for flushing a component are well known in the art. For example, a component or a series of components is flushed by pumping the cleaning composition through the component. After the component is flushed, the cleaning composition can be removed from the component by blowing nitrogen gas, or other gas, through the component. Other suitable cleaning procedures can also be used to contact the cleaning composition of the present invention with the surfaces to be cleaned. In practice, the present methods may be carried out as described herein. One may employ a method using a flush method. In using this method one will recover refrigerant and luricant from the air conditioning or refrigeration system, and disconnect the inlet and outlet of the component that is to be cleaned or flushed from the system. The method is carried out by injecting a suitable composition, such as the composition of the present invention, using a flush kit. Generally, a flush kit includes a pressurized vessel containing the flushing composition, a nozzle for providing the composition to the component to be flushed, along with suitable connecting hoses, and air or nitrogen or other suitable gas to facilitate dispensing of the flushing composition from the vessel. Such flush kits are available commercially from FJC, Inc. Mooresville, N.C., USA. Alternatively, one may use a closed loop method. In this method, one will recover refrigerant and lubricant from the air conditioning or refrigeration system and and disconnect the inlet and outlet of the component that is to be cleaned or flushed from the system. When using a closed loop method, the cleaning is achieved using a suitablclosed loop apparatus. Generally, these closed loop apparatuses include a reservoir of suitable volume, equipped with a pump (operated by air, electricity or other suitable means), hoses, filters, etc. Such closed loop apparatuses are commercially available, for example, from Cliplight Co. in Toronto, Ontario Canada. The hoses that are connected to the closed loop apparatus are connected to the inlet/outlet of the component that is to cleaned or flushed. The flushing composition is circulated through the component from the reservoir for about 30 minutes, or a time sufficient to reduce or remove the residue in the component. The component is then purged with dry air or nitrogen for about 30 to about 60 minutes to remove any flushing composition that may remain in the component. The flushing composition may be used more than once if the closed loop system is equipped with suitable filters and/or separators, etc. | <SOH> BACKGROUND OF THE INVENTION <EOH>There is a need to clean lubricated vapor compression systems and their components during manufacture and service. Vapor compression air conditioning and refrigeration systems are well known in the art. They are used in a wide variety of applications such as heating, air conditioning, and refrigeration. By compressing and expanding a heat transfer agent or refrigerant, these systems absorb and release heat according to the needs of a particular application. Common components of a vapor compression system include: vapor or gas compressors; liquid pumps; heat-transfer equipment such as gas coolers, intercoolers, aftercoolers, heat exchangers, economizers; vapor compressors, such as reciprocating piston compressors, rotating screw compressors, centrifugal compressors, and scroll compressors; evaporators; liquid coolers and receivers; expanders; control valves and pressure-drop throttling devices such as capillaries and orifice tubes; refrigerant-mixture separating chambers; and connecting piping and insulation. These components are typically fabricated from aluminum, copper, brass, steel, various plastics and conventional gasket and O-ring materials. Since vapor compression systems have sliding, rotating or other moving components, most require the use of a lubricant which is mixed with the refrigerant. There is a need from time to time to clean such systems and their components by removing the lubricants as well as other contaminants and debris from their surfaces. Such a need arises, for example, during the retrofit of a chlorofluorocarbon (CFC) to a hydrochlorofluorocarbon (HCFC) or hydrofluorocarbon (HFC), or retrofit of a HCFC refrigerant to a HFC refrigerant, and during service, especially after a catastrophic event such as compressor burnout or mechanical failure. Until recently, CFCs, such as trichloromethane (R-11), and HCFCs, such as 1,1-dichloro-1-fluoroethane (HCFC-141 b), were used as cleaning agents for such systems. Although effective, CFCs and HCFCs are now considered environmentally unacceptable because they are believed to contribute to the depletion of the stratospheric ozone layer. As the use of CFCs and HCFCs is reduced and ultimately phased out, new cleaning agents are needed that not only perform well, but also pose no danger to the ozone layer. A number of environmentally acceptable solvents have been proposed, but their use has been met with limited success. For example, organic solvents, such as hexane, have good cleaning properties and do not deplete the ozone layer, but they are flammable. Aqueous-based cleaning compositions have zero ozone depletion potential and are non-flammable, but they tend to be difficult to remove from the cleaned surfaces due to their relatively low volatility and the presence therein of additives that leave a residue. Additionally, aqueous-based cleaning compositions are often inadequate for cleaning typical organic soils that are present in vapor compression systems. Terpene-based solvents, like aqueous-based cleaning compositions, are difficult to remove from the system. Therefore, a need exists for the identification of environmentally-acceptable cleaning agents that effectively clean vapor compression systems. The present invention fulfills this need. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>Disclosed herein is a composition for reducing and removing residue from a vapor compression air conditioning or refrigeration system, said composition consisting essentially of 1,1,1,2,2,3,4,5,5,5-decafluoropentane and polyol ester, wherein said polyol ester is selected from esters of neopentyl glycol, glycerol, trimethylol propane, pentaerythritol and carboxylic acids represented by the formula HOC(O)R 1 , where R 1 is a C 6-12 saturated, cyclic, straight chain or branched hydrocarbon radical. Also disclosed is a method for reducing residue in a vapor compression air conditioning or refrigeration system, said method comprising: removing substantially all refrigerant and lubricant from said vapor compression air conditioning or refrigeration system, contacting said vapor compression air conditioning or refrigeration system with the composition of the present invention for a period of time sufficient to reduce the amount of residue in said system, and removing said composition from said system. The present invention further comprises a method for cleaning a component of a vapor compression system, said method comprising the steps of: flushing the component with composition of the present invention; and removing said composition from said component. detailed-description description="Detailed Description" end="lead"? | 20050119 | 20071211 | 20050915 | 68231.0 | 0 | WEBB, GREGORY E | VAPOR COMPRESSION AIR CONDITIONING OR REFRIGERATION SYSTEM CLEANING COMPOSITIONS AND METHODS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,039,677 | ACCEPTED | Method of restoring catalytic activity to a spent hydroprocessing catalyst, a spent hydroprocessing catalyst having restored catalytic activity, and a hydroprocessing process | Disclosed is method for restoring catalytic activity to a hydroprocessing catalyst that has become spent due to its use or to the deposition of carbon thereon. The method includes a carbon reduction step whereby carbon is removed from the spent hydroprocessing catalyst in a controlled manner to within a specifically defined concentration range. Following the carbon removal step, the resulting catalyst, having a reduced concentration of carbon, is subjected to a chelation treatment whereby the resulting carbon-reduced catalyst is contacted with a chelating agent and aged for a time period necessary for realizing the benefit from the controlled carbon reduction step. In a preferred embodiment, the catalyst resulting from the chelation treatment is subjected to a sulfurization treatment involving the incorporation of elemental sulfur therein and contacting therewith an olefin. | 1. A method of restoring catalytic activity to a spent hydroprocessing catalyst, said method comprises: providing said spent hydroprocessing catalyst having a first carbon concentration exceeding about 3 weight percent; reducing the concentration of carbon on said spent hydroprocessing catalyst to thereby provide a carbon-reduced catalyst having a second carbon concentration in the range of from about 0.5 weight percent to about 2.5 weight percent by contacting under carbon burning conditions said spent hydroprocessing catalyst with an oxygen-containing gas comprising oxygen and controlling the amount of carbon removed from said spent hydroprocessing catalyst so as to provide said carbon-reduced catalyst having said second carbon concentration; and treating said carbon-reduced catalyst with a chelating agent to thereby provide a revitalized catalyst. 2. A method as recited in claim 1, wherein said treating step comprises: contacting said carbon-reduced catalyst with a solution comprising said chelating agent and a solvent so as to incorporate said chelating agent in said carbon-reduced catalyst; aging for an aging time said carbon-reduced catalyst, having incorporated therein said solution, to thereby provide an aged catalyst wherein said aging time is sufficient to provide for restored catalytic activity to said carbon-reduced catalyst; and drying said aged catalyst to remove a portion of said solvent from said aged catalyst to thereby provide a dried, aged catalyst and to thus provide said revitalized catalyst. 3. A method as recited in claim 2, wherein said treating step further comprises: sulfur treating said dried, aged catalyst to thus provide said revitalized catalyst. 4. A method as recited in claim 3, wherein said chelating agent is selected from the group consisting of aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines. 5. A method as recited in claim 4, wherein said solvent of said solution is water. 6. A method as recited in claim 5, wherein said chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), and diethylenetriaminepentaacetic acid (DTPA). 7. A method as recited in claim 6, wherein said aging time exceeds about 10 hours. 8. A method as recited in claim 7, wherein said first carbon concentration is in the range of from 5 weight percent to 25 weight percent and said second carbon concentration is in the range of from 0.75 weight percent to 1.75 weight percent. 9. A method as recited in claim 8, wherein more than about 50 percent of said chelating agent incorporated into said carbon-reduced catalyst remains in said dried, aged catalyst. 10. A method as recited in claim 9, wherein said cheltating agent is diethylenetriaminepentaacetic acid (DTPA); wherein said aging time exceeds 20 hours; wherein said first carbon concentration is in the range of from 6 weight percent to 20 weight percent; wherein more than 75 weight percent of said chelating agent incorporated into said carbon-reduced catalyst is in said dried, aged catalyst. 11. A method as recited in claim 1, wherein said treating step comprises: contacting said carbon-reduced spent catalyst with a solution comprising said chelating agent and a solvent so as to incorporate said chelating agent in said carbon-reduced spent catalyst; aging for an aging time said carbon-reduced catalyst, having incorporated therein said solution, to thereby provide an aged catalyst wherein said aging time is sufficient to provide for restored catalytic activity to said carbon-reduced catalyst; and drying said aged catalyst to remove a portion of said solvent therefrom and to provide said revitalized catalyst. 12. A method as recited in claim 11, further comprising the step of: sulfur treating said aged catalyst having removed said portion of said solvent therefrom to yield said revitalized catalyst. 13. A method as recited in claim 12, wherein said chelating agent is selected from the group consisting of aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines. 14. A method as recited in claime 13, wherein said solvent of said solution is water. 15. A method as recited in claim 14, wherein said chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), and diethylenetriaminepentaacetic acid (DTPA). 16. A method as recited in claim 15, wherein said aging time exceeds about 10 hours. 17. A method as recited in claim 14, wherein said first carbon concentration is in the range of from 5 weight percent to 25 weight percent and said second carbon concentration is in the range of from 0.75 weight percent to 1.75 weight percent. 18. A method as recited in claim 17, wherein said cheltating agent is diethylenetriaminepentaacetic acid (DTPA); wherein said aging time exceeds 20 hours; wherein said first carbon concentration is in the range of from 6 weight percent to 20 weight percent; and wherein said second carbon concentration is in the range of from 1 weight percent to 1.5 weight percent. 19. A method as recited in claim 18, wherein less than about 50 weight percent of said chelating agent incorporated into said carbon-reduced spent catalyst is removed from said aged catalyst during said drying step. 20. A method, comprising: providing a spent high activity hydroprocessing catalyst having a reduced RVA and a first carbon concentration of deposited carbon, wherein said spent high activity hydroprocessing catalyst is derived from the use of a high activity hydroprocessing catalyst under hydroprocessing conditions whereby carbon is deposited thereon to give said first carbon concentration of deposited carbon; heat treating said spent high activity hydroprocessing catalyst by contacting said spent high activity hydroprocessing catalyst with an oxygen-containing gas under carbon burning conditions to thereby provide a heat treated spent high activity hydroprocessing catalyst having a second carbon concentration; and controlling said second carbon concentration by controlling said carbon burning conditions so as to provide said heat treated spent high activity hydroprocessing catalyst having a maximized regenerated RVA. 21. A method as recited in claim 20, wherein said high activity hydroprocessing catalyst comprises a porous carrier and a catalytically active metal, wherein said high activity hydroprocessing catalyst is made by combining said porous carrier and said catalytically active metal in a manner so as to include a volatile compound; forming an uncalcined catalyst precursor having a volatile content in the range of from 0.5 wt. % to 25 wt. %; and sulfur treating said catalyst precursor to provide said high activity hydrotreating catalyst. 22. A method as recited in claim 21, further comprising: subjecting said heat treated spent high activity hydroprocessing catalyst to a chelating treatment to thereby provide a revitalized catalyst having a revitalized RVA. 23. A method as recited in claim 22, wherein said reduced RVA is less than 0.65, and wherein said revitalized RVA is at least 0.8. 24. A method as recited in claim 23, wherein said chelating treatment comprises: contacting said heat treated spent high activity hydroprocessing catalyst with a solution comprising said chelating agent and a solvent so as to incorporate said chelating agent in said heat treated spent high activity hydroprocessing catalyst; and aging for an aging time said heat treated spent high activity hydroprocessing catalyst, having incorporated therein said solution, to thereby provide an aged catalyst wherein said aging time is sufficient to provide for restored catalytic activity to said carbon-reduced catalyst to thereby provide said revitalized catalyst. 25. A method as recited in claim 24, wherein said chelating treatment further comprises drying said aged catalyst to remove a portion of said solvent therefrom to provide said revitalized catalyst. 26. A method as recited in claim 25, further comprising the step of: sulfurtreating said aged catalyst having removed therefrom said portion of said solvent therefrom to yield said revitalized catalyst. 27. A method as recited in claim 26, wherein said chelating agent is selected from the group consisting of aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines. 28. A method as recited in claim 27, wherein said solvent of said solution is water. 29. A method as recited in claim 28, wherein said chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), and diethylenetriaminepentaacetic acid (DTPA). 30. A method as recited in claim 29, wherein said aging time exceeds about 10 hours. 31. A method as recited in claim 30, wherein said first carbon concentration is in the range of from 5 weight percent to 25 weight percent and said second carbon concentration is in the range of from 0.75 weight percent to 1.75 weight percent. 32. A method as recited in claim 31, wherein said cheltating agent is diethylenetriaminepentaacetic acid (DTPA); wherein said aging time exceeds 20 hours; wherein said first carbon concentration is in the range of from 6 weight percent to 20 weight percent; wherein said second carbon concentration is in the range of from 1 weight percent to 1.5 weight percent; wherein said reduced RVA is less than 0.5; and wherein said revitalized RVA is at least 0.85. 33. A method as recited in claim 20, further comprising: treating said heat treated spent high activity hydroprocessing catalyst with a chelating agent to provide a revilatized catalyst. 34. A method as recited in claim 33, wherein said treating step comprises: contacting said heat treated spent high activity hydroprocessing catalyst with a solution comprising a chelating agent and a solvent so as to incorporate said chelating agent into said heat treated spent high activity hydroprocessing catalyst; and aging for an aging time said heat treated spent high activity hydroprocessing catalyst, having incorporated therein said chelating agent, to thereby provide an aged catalyst wherein said aging time is sufficient to provide for restored catalytic activity to said carbon-reduced catalyst. 35. A method as recited in claim 34, wherein said treating step further comprises: drying said aged catalyst to remove a portion of said solvent from said aged catalyst to thereby provide a dried, aged catalyst. 36. A method as recited in claim 35, further comprising: sulfur treating said aged catalyst having removed said portion of said solvent therefrom to yield said revitalized catalyst. 37. A method as recited in claim 36, wherein said chelating agent is selected from the group consisting of aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines. 38. A method as recited in claim 37, wherein said solvent of said solution is water. 39. A method as recited in claim 38, wherein said chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), and diethylenetriaminepentaacetic acid (DTPA). 40. A method as recited in claim 39, wherein said aging time exceeds about 10 hours. 41. A method as recited in claim 40, wherein said first carbon concentration is in the range of from 5 weight percent to 25 weight percent and said second carbon concentration is in the range of from 0.75 weight percent to 1.75 weight percent. 42. A method as recited in claim 41, wherein said cheltating agent is diethylenetriaminepentaacetic acid (DTPA); wherein said aging time exceeds 20 hours; wherein said first carbon concentration is in the range of from 6 weight percent to 20 weight percent; wherein said second carbon concentration is in the range of from 1 weight percent to 1.5 weight percent; and wherein said reduced RVA is less than 0.5. 43. A method of optimally revitalizing a spent hydroprocessing catalyst having a spent hydrotreating carbon concentration, said method comprises: heat treating said spent hydroprocessing catalyst by contacting said spent hydroprocessing catalyst with an oxygen-containing gas under carbon burning conditions to thereby provide a heat treated spent hydroprocessing catalyst having a reduced carbon concentration below said spent hydrotreating carbon concentration; controlling said reduced carbon concentration by controlling said carbon burning conditions so as to provide said reduced carbon concentration in the range that provides for a catalyst having a restored RVA exceeding about 0.85 after subjecting said heat treated spent hydroprocessing catalyst to a chelating treatment; and, thereafter, subjecting said heat treated spent hydroprocessing catalyst having said reduced carbon concentration to said chelating treatment to thereby provide said revitalized catalyst. 44. A method as recited in claim 43, wherein said spent hydrotreating carbon concentration exceeds about 3.5 wt. %. 45. A method as recited in claim 44, wherein said reduced carbon concentration is in the range of from 0.5 wt. % to 2.5 wt. %. 46. A method as recited in claim 45, wherein said RVA of said revitalized catalyst exceeds 0.85. 47. A catalyst having a restored activity made by the method of claim 1. 48. A composition, comprising: a catalyst having a restored activity comprising a spent hydroprocessing catalyst having deposited thereon a deactivating concentration of carbon, wherein a portion of said deactivating concentration of carbon is removed therefrom by the heat treatment of said spent hydroprocessing catalyst in the presence of an oxygen-containing gas to give an optimized concentration of carbon and, thereafter, the thus-heat treated spent hydroprocessing catalyst has been subjected to a chelating treatment. 49. A hydrotreating process, comprising: contacting a hydrocarbon feedstock under hydrotreatment conditions with the catalyst made by the method of claim 1. | This application claims the benefit of U.S. Provisional Application No. 60/537,502 filed Jan. 20, 2004, the entire disclosure of which is hereby incorporated by reference. BACKGROUND OF THE INVENTION This invention relates to a method of restoring catalytic activity to a spent hydroprocessing catalyst, the resulting hydroprocessing catalyst and its use in a hydroprocessing process. International publication number WO 01/02092 discloses a process for regenerating a used additive-based catalyst. The regeneration step is carried out by contacting the used additive-based catalyst with oxygen at a temperature of no more than 500° C. The resulting regenerated catalyst more preferably has below 1 wt. % carbon content before it is subjected to a rejuvenation step by being contacted with an organic additive. The method of the publication is limited to additive-based catalysts, and the publication does not recognize a need to control the concentration of carbon on the regenerated catalyst to within a specific range in order to obtain a better benefit from its rejuvenation. In fact, this publication suggests that it is best for the carbon content of the regenerated catalyst to be as low as possible before it is undergoes the rejuvenation treatment. This publication does not disclose that its catalyst rejuvenation step requires the organic additive to remain on the catalyst for an aging period prior to drying. European patent application publication EP 0 541 994 A1 discloses a process for regenerating a hydrogenation catalyst, comprising a support, a Group VI metal and a Group VIII metal, and having coke deposited thereon, by controlling the oxidative burning of the coke so as not to reduce the residual coke content to less than 0.5 weight percent and to control it within the range of from 0.5 to 10.0 weight percent. This publication notes that too severe oxidation conditions can negatively change the pore structure, surface area, and active sites of the catalyst. The publication does not provide experimental data that compares the activity of regenerated catalyst with the activity of the fresh catalyst, but it only presents comparative data for certain physical properties of the two catalysts. Also, nothing is disclosed concerning revitalization of a spent catalyst using chelating agents and the relationship between carbon removal and a chelation treatment. U.S. Pat. No. 6,239,066 B1 discloses a process for improving the activity of a catalyst by treatment thereof with a chelating agent. It is noted that the treatment method can also be used to improve the activity of a spent catalyst. Exemplary data presented in an example show that a used catalyst that has been both regenerated and then treated with ethylene diamine tetra acetic acid (EDTA) has better improved relative volumetric activity (RVA) than the used catalyst that has only been regenerated. There is no mention of carbon levels that are on the used catalyst, or the regenerated catalyst, or the regenerated and treated catalyst. There is an ongoing need to find better methods for restoring the activity of catalysts that have lost activity due to their use, particularly, when the catalyst is a spent high activity hydrotreating catalyst. SUMMARY OF THE INVENTION Accordingly, in one inventive method provided is a spent hydroprocessing catalyst having a first carbon concentration exceeding about 3 weight percent. The concentration of carbon on the spent hydroprocessing catalyst is reduced to thereby provide a carbon reduced spent catalyst having a second carbon concentration in the range of from about 0.5 weight percent to about 2.5 weight percent. The reduction of the concentration of carbon on the spent hydroprocessing catalyst is done by contacting under carbon burning conditions the spent hydroprocessing catalyst with a gas comprising oxygen and controlling the amount of carbon removed from the spent hydroprocessing catalyst so as to provide the carbon reduced spent catalyst having the second carbon concentration. The carbon reduced spent catalyst is thereafter treated with a chelating agent to provide a revitalized catalyst. In accordance with another inventive method, catalytic activity of a spent high activity hydroprocessing catalyst having a reduced RVA and a concentration of deposited carbon is restored to a maximized regenerated RVA. This method includes providing a spent high activity hydroprocessing catalyst having the reduced RVA and the concentration of deposited carbon. The spent high activity hydroprocessing catalyst is derived from the use of a high activity hydroprocessing catalyst under hydroprocessing conditions by which carbon is deposited thereon to give the concentration of deposited carbon. The spent high activity hydroprocessing catalyst is heat treated by contacting it with an oxygen-containing gas under carbon burning conditions to thereby provide a heat treated spent high activity hydroprocessing catalyst having a reduced carbon concentration. The reduced carbon concentration is controlled by controlling the carbon burning conditions so as to provide the heat treated spent high activity hydrotreating catalyst having the maximized regenerated RVA. In accordance with yet another invention, provided is a catalyst having restored activity and comprising a spent hydroprocessing catalyst having deposited thereon a deactivating concentration of carbon, wherein a portion of the deactivating concentration of carbon is removed therefrom by the heat treatment of the spent hydroprocessing catalyst in the presence of an oxygen-containing gas to give an optimized concentration of carbon and, thereafter, the thus-heat treated spent hydrotreating catalyst has been subjected to a chelating treatment. The catalyst having restored activity and those catalysts made by the aforementioned methods can be used in a hydroprocessing process comprising contacting the revitalized hydroprocessing catalyst with a hydrocarbon feedstock under hydroprocessing conditions. Other objects and advantages of the invention will become apparent from the following detailed description and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plot of the relative volumetric activity of a revitalized hydrotreating catalyst, which was prepared by the inventive method whereby a spent hydrotreating catalyst was treated first by removing a portion of the carbon thereon followed by a chelation treatment, as a function of the remaining carbon content of the spent hydrotreating catalyst after the carbon removal step. DETAILED DESCRIPTION OF THE INVENTION The invention relates to a method of restoring catalytic activity to a hydroprocessing catalyst that has become spent due to its use. The invention further relates to a method for maximizing the amount of restored catalytic activity to the spent hydroprocessing catalyst. Also, the invention relates to a revitalized hydroprocessing catalyst and other catalyst compositions made by the treatment of a spent hydroprocessing catalyst using the inventive methods described herein. Further, the invention relates to a hydroprocessing process that utilizes the revitalized hydroprocessing catalysts and other spent catalysts having restored catalytic activity of the invention. The hydroprocessing catalyst of the invention can be any suitable hydrogenation catalyst including conventional hydroprocessing catalysts that comprise a metal component on a support material. The metal component can include a Group VIB metal component or a Group VIII metal component, or both metal components. It is preferred for the hydroprocessing catalyst to comprise both a Group VIB metal component and a Group VIII metal component. The hydroprocessing catalyst can also include a promoter such as a phosphorous component. The Group VIII metal component of the hydroprocessing catalyst composition are those Group VIII metal or metal compounds that, in combination with the other components of the catalyst composition, suitably provide a hydroprocessing catalyst. The Group VIII metal can be selected from the group consisting of nickel, cobalt, palladium and platinum. Preferably, the Group VIII metal is either nickel or cobalt and, most preferably, the Group VIII metal is cobalt. The Group VIII metal component contained in the hydroprocessing catalyst composition can be in the elemental form or in the form of a metal compound, such as, for example, oxides, sulfides and the like. The amount of Group VIII metal in the hydroprocessing catalyst composition can be in the range of from about 0.1 about 6 weight percent elemental metal based on the total weight of the hydroprocessing catalyst composition. Preferably, the concentration of Group VIII metal in the hydroprocessing catalyst composition is in the range of from 0.3 weight % to 5 weight %, and, most preferably, the concentration is in the range of from 0.5 weight % to 4 weight %. The Group VIB metal component of the hydroprocessing catalyst composition are those Group VIB metal or metal compounds that, in combination with the other elements of the hydroprocessing catalyst composition, suitably provide a hydroprocessing catalyst. The Group VIB metal can be selected from the group consisting of chromium, molybdenum and tungsten. The preferred Group VIB metal is either molybdenum or chromium and, most preferred, it is molybdenum. The Group VIB metal component contained in the hydroprocessing catalyst composition can be in the elemental form or in the form of a metal compound, such as, for example, oxides, sulfides and the like. The amount of Group VIB metal in the hydroprocessing catalyst composition can be in the range of from about 5 to about 25 weight percent elemental metal based on the total weight of the hydroprocessing catalyst composition. Preferably, the concentration of Group VIB metal in the hydroprocessing catalyst composition is in the range of from 6 weight % to 22 weight %, and, most preferably, the concentration is in the range of from 7 weight % to 20 weight %. The support material of the hydroprocessing catalyst can be any material that suitably provides a support for the metal hydrogenation components of the hydroprocessing catalyst including porous refractory oxides. Examples of possible suitable porous refractory oxides include silica, magnesia, silica-titania, zirconia, silica-zirconia, titania, titania-alumina, zirconia-alumina, silica-titania, alumina, silica-alumina, and alumino-silicate. The alumina can be of various forms, such as, alpha alumina, beta alumina, gamma alumina, delta alumina, eta alumina, theta alumina, boehmite, or mixtures thereof. The preferred porous refractory oxide is amorphous alumina. Among the available amorphous aluminas, gamma alumina is most preferred. The porous refractory oxide generally has an average pore diameter in the range of from about 50 Angstroms to about 200 Angstroms, preferably, from 70 Angstroms to 175 Angstroms, and, most preferably, from 80 Angstroms to 150 Angstroms. The total pore volume of the porous refractory oxide, as measured by standard mercury porisimetry methods, is in the range of from about 0.2 cc/gram to about 2 cc/gram. Preferably, the pore volume is in the range of from 0.3 cc/gram to 1.5 cc/gram, and, most preferably, from 0.4 cc/gram to 1 cc/gram. The surface area of the porous refractory oxide, as measured by the B.E.T. method, generally exceeds about 100 m2/gram, and it is typically in the range of from about 100 to about 400 m2/gram. One inventive method is specifically directed to the treatment of a high activity hydroprocessing that has become spent catalyst in order to restore a portion of the catalytic activity that has been lost typically due to use or to the deposition of carbon thereon, or to both. This spent high activity hydroprocessing catalyst can have a relative volumetric activity (RVA) that is reduced below its RVA when in a fresh state, and it can have a concentration of deposited carbon. As the term is used in this specification, “relative volumetric activity” (RVA) refers to the catalytic activity with respect to either hydrodesulfurization (HDS) or hydrodenitrogenation (HDN) of a specific catalyst that has been used relative to the catalytic activity of the same specific catalyst when in its fresh, unused state. Thus, the RVA of the fresh, unused reference catalyst is by definition 1. The RVA of the evaluated catalyst can be represented by the following formula: RVA=(Rate Constant for evaluated catalyst)/(Rate Constant for fresh reference catalyst) where for the case of hydrodesulfurization (HDS) RVA, the Rate Constants are calculated assuming an HDS reaction order of 1.3, and for the case of hydrodenitrogenation (HDN) RVA, the Rate Constants are calculated assuming an HDN reaction order of 1.0. The high activity hydroprocessing catalyst is a sulfur-treated hydroprocessing catalyst comprising a porous refractory oxide and a metal hydrogenation component and is prepared by a specific method that provides for its high activity and other desirable properties. The high activity hydroprocessing catalyst can be prepared by first combining the porous refractory oxide support material and at least one metal hydrogenation component in a manner so as to include a volatile compound to thereby provide a catalyst precursor. The volatile compound is a compound used in the formation of the catalyst precursor, and it is generally selected from the group consisting of water, organic solvents, such as aliphatic and aromatic hydrocarbons, alcohols, ketones, organic ligands, and any combination thereof. The catalyst precursor, thus, can comprise porous refractory oxide support material, a metal hydrogenation component, and a concentration of the volatile compound. This catalyst precursor is then subjected to a sulfur treatment step to incorporate sulfur, either elemental sulfur or a sulfur compound, or a combination of both, into the catalyst precursor to thereby provide a sulfur treated catalyst precursor. The sulfur treatment step used to provide the sulfur treated catalyst precursor can include the simultaneous or subsequent reduction of the concentration of the volatile compound that is in the catalyst precursor to give the high activity hydrotreating catalyst. The porous oxide support material and metal hydrogenation components of the catalyst precursor are combined using any suitable and known method for combining such catalyst components and can include such methods as impregnation, co-mulling, and co-precipitation. It is preferred, however, for the porous refractory oxide support material to first be formed into particles, such as extrudates, pills and other agglomerates, and for the metal hydrogenation components to be incorporated into the particles by known incipient wetness impregnation methods. The metal impregnation solution used to incorporate the metal compound or compounds into the porous refractory oxide support can be the source of the volatile compound and can include, as mentioned above, water, or an alcohol compound, or an organic solvent or a combination thereof. It is preferred for the metal impregnation solution to be an aqueous solution of the metal compound. The metal compounds suitable for use in forming the metal impregnation solution are those compounds that are soluble in the particular solvent used to form the impregnation solution and which are convertible to metal sulfide upon further treatment. Group VIII metal compounds that may be used in the metal impregnation solution can include, for example, Group VIII metal carbonates, Group VIII metal nitrates, Group VIII metal sulfates, Group VIII metal thiocynates, Group VIII metal oxides and mixtures of any two or more thereof. Group VIB metal compounds that may be used in the metal impregnation solution can include, for example, Group VIB metal oxides, Group VIB metal sulfides, Group VIB carbonyl compounds, Group VIB acetate compounds, elemental Group VIB metals in solution and mixtures of any two or more thereof. For the preferred Group VIB metal compounds of molybdenum, molybdates and phosphomolybdate can be used. The concentration of the metal compounds in the metal impregnation solution is selected so as to provide the desired metal concentration in the final catalyst composition. Typically, the concentration of the metal compound in the impregnation solution is in the range of from 0.01 to 100 moles per liter of solution. The catalyst precursor that is to be further subjected to a sulfur treatment step is to have a concentration of volatile compound of no less than 0.5 weight percent, based on the total weight of the catalyst precursor, and, generally, the amount of volatile compound in the catalyst precursor should be in the range of from 0.5 weight percent to 25 weight percent. The preferred concentration of volatile compound in the catalyst precursor is in the range of from 2 weight percent to 25 weight percent, and, most preferred, it is in the range of from 4 weight percent to 10 weight percent. While prior to its sulfur treatment the catalyst precursor can, optionally, be dried in order to control the concentration of volatile compound in the catalyst precursor to within the aforementioned ranges, it is not to be subjected to calcination temperature conditions prior to the sulfur treatment step. Thus, the catalyst precursor is not calcined prior to incorporation therein of sulfur or a sulfur compound. Calcination temperature conditions are those temperatures at or exceeding 400° C., and they are usually in the range of from 400° C. to 600° C. Thus, the catalyst precursor can be exposed to a temperature of less than 400° C. prior to the sulfurization step; provided, the temperature conditions are not such that the resulting concentration of volatile compound in the resultant catalyst precursor is within the desired concentration ranges as noted above. Typically, the catalyst precursor can be dried in the presence of air at a drying temperature in the range from ambient to 400° C., but, more typically, from 30° C. to 250° C. The catalyst precursor having a concentration of volatile compound within the range as described above undergoes a sulfur treatment step by which sulfur or a sulfur compound is incorporated into the catalyst precursor to thereby provide the high activity hydrotreating catalyst. Any suitable method known to those skilled in the art can be used to treat the catalyst precursor with sulfur or a sulfur compound to yield the high activity hydrotreating catalsyt including, for example, both the known in-situ and ex-situ sulfurization and sulfiding methods. The use herein of such terms as sulfur treatment or treatment with sulfur or sulfur-treated or other similar type terminology is meant to refer to and to encompass sulfurization methods and sulfiding methods and methods that include the combination of both sulfurization and sulfiding, whether such methods are performed in-situ (i.e., within a process reactor zone) or ex-situ (i.e., external to a process reactor zone) or by any combination of in-situ or ex-situ treatment methods. In a typical in-situ sulfiding method, the catalyst precursor is placed in a reactor vessel that defines a reaction zone. A fluid stream containing a sulfur compound is passed over the catalyst precursor and contacted therewith under such suitable temperature conditions as to provide a sulfided catalyst, and, thus, the high activity hydrotreating catalyst. The sulfur compound can include any known and suitable sulfiding agent, such as hydrogen sulfide, organic sulfur compounds that are typically found in petroleum hydrocarbon feeds, and other organic sulfur compounds such as dimethylsulfide, dimethyldisulfide, dimethylsulfoxide, dimethylmercaptan, butylmercaptan, and carbon disulfide. Typical temperatures at which the sulfiding fluid stream is contacted with the catatlyst precursor can be in the range of from 150° C. to 400° C., and, more typically, from 200° C. to 350° C. In the ex-situ sulfiding method, the catalyst precursor is sulfided prior to its loading into the reactor vessel. The ex-situ sulfiding method can include any number of suitable sulfiding methods including, for example, the contacting of the catalyst precursor with a sulfiding agent, such as mentioned above, or with a hydrogen sulfide-containing fluid, under elevated temperature conditions followed by an optional passivation step. The preferred sulfurization step provides for the incorporation of sulfur into the catalyst precursor by contacting the catalyst precursor with elemental sulfur under conditions that cause the sulfur to be incorporated into the pores of the catalyst precursor either by sublimation or by melting, or by a combination of both. Suitable sulfurization methods for this sulfur incorporation are described in detail in U.S. Pat. No. 5,468,372, which is incorporated herein by reference. There are two general methods for carrying out the sulfurization of the catalyst precursor with elemental sulfur. The first and preferred method comprises contacting the catalyst precursor with elemental sulfur at a temperature such that the elemental sulfur is substantially incorporated in the pores of the catalyst precursor by sublimation and/or melting and subsequently heating the thus sulfur-incorporated catalyst precursor in the presence of a liquid olefinic hydrocarbon at a temperature greater than about 150° C. The second method comprises contacting the catalyst precursor with a mixture of powdered elemental sulfur and a liquid olefinic hydrocarbon and heating the resultant mixture of olefin, sulfur and catalyst precursor to a temperature above about 150° C. In this procedure, the heating rate is sufficiently slow such that the sulfur is incorporated into the pores of the catalyst precursor by sublimation and/or melting prior to reaching the temperature at which the olefin reacts to make the sulfur more resistant to removal by stripping. In the preferred sulfurization method, the catalyst precursor is first contacted with elemental sulfur at a temperature such that the sulfur is incorporated thereon by sublimation and/or melting. While the catalyst precursor can be contacted with sulfur in the molten state, it is preferred to first admix the catalyst precursor with powdered elemental sulfur and then heat the resultant mixture of sulfur and catalyst precursor to above the temperature at which sublimation of the sulfur occurs. Generally, the catalyst precursor is heated in the presence of the powdered elemental sulfur at a temperature greater than about 80° C. Preferably, this sulfur impregnation step will be carried out at a temperature ranging from about 90° C. to about 130° C. or higher, for example, up to the boiling point of sulfur of about 445° C. It is preferred for the catalyst precursor and sulfur to be heated together at a temperature ranging from about 105° C. to about 125° C. Typically, the catalyst precursor and powdered sulfur is placed in a vibratory or rotary mixer and heated to the desired temperature for sufficient time to allow the sulfur to be incorporated into the pores of the catalyst precursor. The time period for heating typically will range from about 0.1 hour to about 10 hours or longer. The amounts of sulfur used will depend upon the amounts of catalytic metal present in the catalyst precursor that needs to be converted to the sulfide. Typically the amount of sulfur used is determined on the basis of the stoichiometric amount of sulfur required to convert all of the metal in the catalyst precursor to the sulfide form. For example a catalyst precursor containing molybdenum would require two moles of sulfur to convert each mole of molybdenum to molybdenum disulfide, with similar determinations being made for other metals. The sulfur-incorporated catalyst precursor is then contacted with a liquid olefin at such an elevated temperature and time period that the olefin reacts and provides the high activity hydrotreating catalyst. Typically, the contact temperature is greater than about 150° C., and, more typically, it will range from about 150° C. to about 350° C., preferably from about 200° C. to about 325° C. Contact times will depend on the temperature and vapor pressure of the olefin, with higher temperatures and higher vapor pressures requiring shorter times. In general, contact times will range from about 0.1 hour to about 10 hours. It is important for the olefin to be liquid at the elevated temperature of contact. It is preferred for the olefin to be a higher olefin, i.e., one having a carbon number greater than six, preferably greater than eight. In one embodiment of the preferred sulfurizing method, the catalyst precursor is contacted simultaneously with both the elemental sulfur, preferably in powdered form, and the olefinic hydrocarbon. According to this method, a mixture of powdered elemental sulfur and olefinic hydrocarbon solvent is first produced. A ratio of oil to sulfur by weight ranging from about 1:1 to about 4:1 is suitable, with about 2:1 being a preferred ratio. The mixture may be heated to promote homogenous mixing of the components, particularly if the olefinic hydrocarbon is not liquid at ambient conditions. Toluene or other lightweight hydrocarbon solvents may be added to decrease the viscosity of the mixture. Also, increased heat will achieve the same effect. The mixture of olefin and sulfur is then added to a preweighted catalyst precursor and mixed therewith. The mixture of catalyst precursor, olefin and sulfur is then heated to the olefin reaction temperature of above about 150° C. Preferably, the temperature is in the range of from about 150° C. to about 350° C., and, more preferably, from about 200° C. to about 325° C. The heating time is in the range of from about 0.1 to about 10 hours. A sulfurized catalyst precursor may also be further treated with sulfur by sulfiding either in-situ or ex-situ or a combination thereof. A significant aspect of the inventive method is that it is directed to the restoration of the catalytic activity of a hydroprocessing catalyst, including a high activity hydrotreating catalyst, that has been lost as a result of use thereof, such as use under hydrotreating conditions, or carbon deposition thereon. It is understood that, as used in this specification, the term hydroprocessing catalyst is defined as being broad enough to include the high activity hydroprocessing catalyst as described above in detail. Thus, references herein to hydroprocessing catalyst also include or encompass high activity hydroprocessing catalyst. It is recognized that the inventive methods described herein are particularly applicable to the processing of high activity hydrotreating catalyst due to their unique and specific properties. The hydroprocessing catalyst can be used in the hydrotreatment of a hydrocarbon feedstock under suitable hydrotreatment process conditions. Typical hydrocarbon feedstocks can include petroleum-derived oils, for example, atmospheric distillates, vacuum distillates, cracked distillates, raffinates, hydrotreated oils, deasphalted oils, and any other hydrocarbon that can be subject to hydrotreatment. More typically, the hydrocarbon feedstock that is treated with the hydroprocessing catalyst is a petroleum distillate such as a straight run distillate or a cracked distillate with the hydrotreatment being to remove sulfur from sulfur-containing compounds or nitrogen from nitrogen-containing compounds, or both, from the hydrocarbon feedstock. More specifically, the hydrocarbon feedstock can include such streams as naphtha, which typically contains hydrocarbons boiling in the range of from 100° C. (212° F.) to 160° C. (320° F.), kerosene, which typically contains hydrocarbons boiling in the range of from 150° C. (302° F.) to 230° C. (446° F.), light gas oil, which typically contains hydrocarbons boiling in the range of from 230° C. (446° F.) to 350° C. (662° F.), and even heavy gas oils containing hydrocarbons boiling in the range of from 350° C. (662° F.) to 430° C. (806° F.) The hydrotreating conditions to which the hydroprocessing catalyst is subjected are not critical and are selected as is required taking into account such factors as the type of hydrocarbon feedstock that is treated and the amounts of sulfur and nitrogen contaminants contained in the hydrocarbon feedstock. Generally, the hydrocarbon feedstock is contacted with the hydroprocessing catalyst in the presence of hydrogen under hydrotreatment conditions such as a hydrotreating contacting temperature generally in the range of from about 150° C. (302° F.) to about 538° C. (1000° F.), preferably from 200° C. (392° F.) to 450° C. (842° F.) and most preferably from 250° C. (482° F.) to 425° C. (797° F.). The hydrotreating total contacting pressure is generally in the range of from about 500 psia to about 6,000 psia, which includes a hydrogen partial pressure in the range of from about 500 psia to about 3,000 psia, a hydrogen addition rate per volume of hydrocarbon feedstock in the range of from about 500 SCFB to about 10,000 SCFB, and a hydrotreating liquid hourly space velocity (LHSV) in the range of from about 0.2 hr−1 to 5 hr−1. The preferred hydrotreating total contacting pressure is in the range of from 500 psia to 2,500 psia, most preferably, from 500 psia to 2,000 psia, with a preferred hydrogen partial pressure of from 800 psia to 2,000 psia, and most preferred, from 1,000 psia to 1,800 psia. The LHSV is preferably in the range of from 0.2 hr−1 to 4 hr−1, and, most preferably, from 0.2 to 3 hr−1. The hydrogen addition rate is preferably in the range of from 600 SCFB to 8,000 SCFB, and, more preferably, from 700 SCFB to 6,000 SCFB. The spent hydroprocessing catalyst has a catalytic activity lower than the catalytic activity of such catalysts when in the fresh state as reflected in the relative volumetric activity (RVA) being less than 1. Generally, the hydroprocessing catalyst is considered spent when the RVA is less than 0.65, but economic and process considerations usually determine the point at which a catalyst is considered spent. Thus, the spent hydroprocessing catalyst can even have an RVA less than 0.5 and even less than 0.4. The hydroprocessing catalyst can become spent by use under hydrotreatment conditions as described above. It is generally considered that one cause of the loss of catalytic activity is due to the deposition of carbonaceous material into the pore structure of the hydroprocessing catalyst as a result of its use and that the spent hydroprocessing catalyst can have a carbon content generally above 3 weight percent with the weight percent being based on the total weight of the spent hydroprocessing catalyst including carbon and other components deposited upon the hydroprocessing catalyst. Typically, the carbon content of the spent hydroprocesing catalyst is in the range of from 5 weight percent to 25 weight percent, and, more typically, the carbon content is in the range of from 6 weight percent to 20 weight percent. An important feature of the inventive method for maximizing the restoration of catalytic activity to the spent hydroprocessing catalyst is for the carbon reduction of the first step to be such as to provide a controlled concentration of carbon on the spent hydroprocessing catalyst such that when it undergoes a subsequent treatment with a chelating agent in accordance with the inventive method a revitalized catalyst having the desired restored catalytic activity is provided. It has been found, unexpectedly, that to gain the best benefit from the treatment with the chelating agent there is an optimum amount of carbon that should remain on the spent hydroprocessing catalyst after the carbon reduction step. To provide for the best improvement in the restoration of catalytic activity from the chelation treatment, the spent hydroprocessing catalyst should first have its carbon content reduced to a level that is no less than about 0.5 weight percent to thereby provide a carbon-reduced catalyst, and, generally, the carbon concentration of the carbon-reduced catalyst should be in the range of from 0.5 weight percent to 2.5 weight percent. To provide for a greater amount of restored catalytic activity after the chelation treatment, the carbon concentration on the carbon-reduced catalyst should be in the range of from 0.75 weight percent to 2 weight percent, and, preferably, the carbon concentration is in the range of from 1 weight percent to 1.75 weight percent. If the carbon concentration of the carbon-reduced catalyst is controlled within the required concentration range in accordance with the inventive method, catalytic activity can be restored to the spent hydroprocessing in a manner that an optimum or maximum level of restored catalytic activity is obtained. This maximized regenerated RVA exceeds, and, preferably, substantially exceeds, the reduced RVA of the spent hydroprocessing catalyst. Thus, generally, the maximized regenerated RVA of the carbon-reduced catalyst can be greater than 0.65. But, it is most desirable for the maximized regenerated RVA to be as high as is achievable, thus, it can be greater than 0.7 and even greater than 0.75. In most instances, the practical upper limit for the maximized regenerated RVA is 0.9. Any suitable method know in the art can be used to reduce the carbon concentration on the spent hydroprocessing catalyst to thereby provide the carbon-reduced catalyst, but a preferred method includes heat treating the spent hydroprocessing catalyst by contacting it with an oxygen-containing gas, comprising oxygen, under suitable carbon burning conditions and in a controlled manner so as to combust or burn or oxidize the carbon that is on the spent hydroprocessing catalyst and so as to provide the carbon-reduced catalyst having a reduced carbon concentration that is less than the carbon concentration on the spent hydroprocessing catalyst. It is a particularly important aspect of the inventive process for the carbon concentration on the carbon-reduced catalyst to be controlled to within the specific ranges as noted above so that when the carbon-reduced catalyst is subsequently subjected to a treatment with the chelating agent the restored catalytic activity is maximized. The required carbon burning conditions can be dependent upon the amount of carbon on the spent hydroprocessing catalyst and the desired carbon concentration on the carbon-reduced catalyst. Generally, the spent hydroprocessing catalyst is contacted with the oxygen-containing gas under such conditions that the temperature of the spent hydroprocessing catalyst does not exceed 500° C. with a suitable heat treatment, or carbon burning, temperature being in the range of from about 300° C. to about 500° C. The preferred carbon burning temperature is in the range of from 320° C. to 475° C., and, most preferably, from 350° C. to 425° C. The oxygen concentration of the oxygen-containing gas can be controlled so as to provide the desired carbon burning temperature conditions. The oxygen-containing gas is preferably air, which can be diluted with other gases, for instance, inert gases such as nitrogen, to control the concentration of oxygen in the oxygen-containing gas. The carbon burn can be conducted within a combustion zone wherein is placed the spent hydroprocessing catalyst and into which is introduced the oxygen-containing gas. The time period for conducting the carbon burn is not critical and is such as to provide a carbon-reduced catalyst, having the desired carbon concentration, and it is generally in the range of from about 0.1 hours to 48 hours, or more. The carbon-reduced catalyst, having the specifically defined carbon concentration, undergoes a treatment with a chelating agent to thereby provide a revitalized catalyst that has a restored catalytic activity. One suitable chelation treatment method is described in detail in U.S. Pat. No. 6,291,394, which is incorporated herein by reference. In the preferred treatment method, the carbon-reduced catalyst is contacted, or wetted, with a chelating agent, which is preferably dissolved in a liquid carrier, in such a manner as to assure that the chelating agent is adequately incorporated into the carbon-reduced catalyst. This contacting is then followed by an aging period during which time the chelating agent is allowed to remain on the carbon-reduced catalyst to provide an aged catalyst. This aged catalyst then undergoes a heat treatment that can include drying or calcination, or both, followed by sulfur treatment to provide a catalyst with restored catalytic activity. The chelating agent, or chelant, suitable for use in the chelating treatment step of the inventive method includes those compounds that are capable of forming complexes with the metal components, such as any of the Group VIII metals and Group VIB metals, contained in the carbon-reduced catalyst. It is particularly important to the inventive method that the chelant have properties that provide for the restoration of catalytic activity in the carbon-reduced catalyst. While not wanting to be bound to any particular theory, it is nevertheless believed that the chelating agent provides for the restoration of catalytic activity by re-dispersing the active metals contained in the carbon-reduced catalyst that have become agglomerated due to prior use and exposure to high temperatures, including exposure to carbon burning conditions of the hydroprocessing catalyst and its derivatives from which the carbon-reduced catalyst is derived. The amount of metal redispersion may be demonstrated and observed through electron microscopic photographs. The chelating agent is added to the carbon-reduced catalyst in a liquid form preferably by use of a solution containing the chelating agent which complexes with the agglomerated metal of the carbon-reduced catalyst. The complexes are, thus, in a liquid phase that provides for mobility of the complexes and assists in the transport of the metal throughout the carbon-reduced catalyst to thereby provide for the re-dispersion of the metals. Any chelant compound that suitably provides for the benefit of restored catalytic activity as required by the inventive method described herein can be used in the chelating treatment of the carbon-reduced catalyst. Among these chelant compounds are those chelating agents that contain at least one nitrogen atom that can serve as the electron donor atom for forming the complexes with the metals of the carbon-reduced catalyst. Examples of possible nitrogen atom containing chelating agents include those compounds that can be classified as aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines. Examples of aminocarboxylic acids include ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTPA), and nitrilotriacetic acid (NTA). Examples of polyamines include ethylenediamine, diethylenetriamine, triethylenetetramine, and triaminotriethylamine. Examples of aminoalcohols include triethanolamine (TEA) and N-hydroxyethylethylenediamine. The preferred chelating agent for use in the inventive method is an aminocarboxylic acid that can be represented by the following formula: Wherein R1, R2, R3, R4 and R5 are each independently selected from alkyl, alkenyl, and allyl with up to 10 carbon atoms and which may be substituted with one or more groups selected from carbonyl, carboxyl, ester, ether, amino, or amide; wherein R6 and R7 are each independently selected from an alkylene group with up to 10 carbon atoms; wherein n is either 0 or 1; and wherein one or more of the R1, R2, R3, R4 and R5 has the formula: Wherein, R8 is an alkylene having from 1 to 4 carbon atoms; and wherein the X is either hydrogen or another cation. Preferred chelating agents include ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetriacetic acid (HEDTA), and diethylenetriaminepentaacetic acid (DTPA). The most preferred chelating agent is DTPA. Any suitable means or method can be used to contact the carbon-reduced catalyst with the chelating agent or solution having a concentration of chelating agent; provided, such means or method provides for the suitable incorporation or impregnation of the chelating agent within the pores of the carbon-reduced catalyst. Examples of suitable methods of applying the chelating agent or chelating solution to the carbon-reduced catalyst can include dipping or spraying. A preferred method for contacting the carbon-reduced catalyst with the chelating agent or chelating solution is by any suitable impregnation method known to those skilled in the art, for instance, impregnation by incipient wetness whereby the amount or volume of chelating solution added to the carbon-reduced catalyst is such that the total volume of the added chelating solution is such that it is in the range of up to about the total pore volume of the carbon-reduced catalyst to be impregnated with the chelating solution. The chelating solution can be a solution comprising the chelating agent and a solvent that suitably provides for the dissolution of the chelating agent. Possible solvents include water and alcohols, such as, methanol and ethanol, with water being the preferred solvent for the chelating agent. The amount of chelating agent that is applied to the carbon-reduced catalyst should be such as to provide for the desired restored catalytic activity as described herein; and, generally, the amount is such as to incorporate into the carbon-reduced catalyst chelating agent in the range of from about 0.005 moles chelant to about 1 mole chelant per mole of active metal, i.e., Group VIII and Group VIB metals described above, that is in the carbon-reduced catalyst. It is more preferred to add to the carbon-reduced catalyst an amount of chelating agent that is in the range of from 0.01 to 0.5 moles of added chelating agent per mole of hydrogenation metal in the carbon-reduced catalyst. Most preferred, the amount of chelating agent added to the carbon-reduced catalyst is in the range of from 0.05 to 0.1 moles of added chelant per mole of hydrogenation metal. It is recognized that a significant aspect of the invention is that, by combining the carbon removal step, which provides a concentration of remaining carbon on the carbon-reduced catalyst controlled to within a specific critical range, with the chelating agent treatment step, a revitalized catalyst can be provided having a higher level of restored catalytic activity than that which is provided using alternative methods for treating a spent hydroprocessing catalyst. And, additionally, it has been discovered that in order to realize the benefit from the combined steps of a controlled carbon removal from a spent hydroprocessing catalyst followed by a chelating agent treatment of the resulting carbon-reduced catalyst, it is essential for the chelating agent treatment step to include an aging or soaking of the carbon-reduced catalyst for a sufficiently long time period. If this time period is not long enough, no significant benefit is recognized. The carbon-reduced catalyst having incorporated therein the chelating agent is, thus, aged for an aging time period necessary to provide for the enhancement of restored catalytic activity. It is theorized that a sufficiently long aging period is required in order to allow for the chelant to react with the metals of the carbon-reduced catalyst to thereby form chelates and to allow the re-dispersion of the metals. In any event, there is a minimum time required for the aging period before a significant incremental benefit is seen in the restored catalytic activity of the carbon-reduced catalyst that is treated with the chelant. This minimum aging time can depend upon the temperature at which the aging is conducted and the type and amount, relative to the carbon-reduced catalyst, of chelant used. Generally, for the preferred amino carboxylic acid chelating agents to obtain any significant benefit from the aging, it is important, if not essential, for the aging time period to exceed about 10 hours, but, preferably, the aging time period should exceed 20 hours, and, most preferably, 40 hours. There is also a maximum amount of aging time at which no significant incremental increase in restored catalytic activity is achieved. The maximum aging time is generally no more than 1200 hours. The preferred maximum aging time is less than 1000 hours and, more preferred, the maximum aging time is less than 750 hours. Thus, the aging time period for contacting the carbon-reduced catalyst or for allowing the chelating agent that is incorporated within the pores of the carbon-reduced catalyst to remain thereon or to soak is in the range of from about 10 hours to about 1200 hours, preferably from 20 hours to 1000 hours, and, most preferably, from 40 hours to 750 hours. The aging temperature of which the aging is conducted can be any temperature that provides for the aged catalyst with at least some redispersion of the metals of the carbon-reduced catalyst and can generally be in the range of from about ambient temperature, for example, from about 10° C. to about 37° C., to about 50° C. or 60° C. The aged catalyst is then subjected to a heat treatment that can include drying or calcination, or both. But, it is preferred that the aged catalyst not be subjected to calcinations conditions. The drying of the aged catalyst is to remove at least a portion of the solvent of the chelating solution from the aged catalyst while leaving at least a portion, preferably a major portion of the chelating agent on the aged catalyst. In a preferred embodiment of the invention, it is important for the dried, aged catalyst to include therein an amount or a concentration of chelant when it undergoes a sulfur treatment, which is similar, if not identical, to the sulfur treatments described above with respect to the preparation or manufacture of a high activity hydroprocessing catalyst. In the drying of the aged catalyst it is desirable to remove as little of the chelant from the aged catalyst as is practical and, thus, more than about 50 weight percent of the chelant that is incorporated into the carbon-reduced catalyst, based on the total weight of chelant incorporated into the carbon-reduced catalyst, will remain in the resulting dried, aged catalyst. Preferably, the amount of chelant remaining on the dried, aged catalyst exceeds 75 weight percent, and, most preferably, more than 90 weight percent of the chelant originally added to the carbon-reduced catalyst remains in the carbon-reduced catalyst when it is subjected to the sulfurization treatment. Thus, less than about 50 weight percent of the chelant originally added to the carbon-reduced catalyst in the chelation treatment thereof should be removed from the aged catalyst during the drying step. Preferably, less than 25 weight percent and, most preferably, less than 10 weight percent, of the chelant incorporated into the carbon reduced catalyst is removed from the aged catalyst when it is desired. The drying can be conducted by any suitable method known to those skilled in the art. Typically, to dry the aged catalyst, hot air or any other suitable gas, such as nitrogen and carbon dioxide, is passed over the aged catalyst. The drying temperature should not exceed 200° C., and, can generally be in the range of from 90° C. to 180° C. Preferably, the drying temperature is less than 175° C. and can range from 100° C. to 175° C. The drying step is carefully controlled in order to avoid either evaporating or converting the chelant or chelates. In a preferred embodiment of the invention, the dried, aged catalyst having remaining therein, as discussed above, chelant or chelate is subjected to a sulfur treatment in order to re-sulfide the hydrogenation metal components that are in the oxide form. The sulfur treatment of the dried, aged catalyst is the same sulfur treatment methods as are described above with respect to the sulfur treatment of the catalyst precursor in the preparation or manufacture of the high activity hydroprocessing catalyst. The revitalized catalyst of the invention will have a restored catalytic activity such that its RVA is greater than 0.80, but, more particularly, the RVA of the revitalized catalyst is greater than 0.85. It is preferred to maximize the amount of restored activity to a spent hydroprocessing catalyst by the inventive method, and, thus, it is preferred for the RVA of the revitalized catalyst to exceed 0.90 and, most preferably, the RVA exceeds 0.95. The hydroprocessing catalysts treated in accordance with the methods described herein can be suitably used to hydrotreat hydrocarbon feedstocks under hydrotreating conditions as fully described hereinabove. The following Examples are presented to illustrate the invention, but they should not be construed as limiting the scope of the invention. EXAMPLE 1 This Example 1 describes the laboratory method used to revitalize and restore catalytic activity to a commercially available hydroprocessing catalyst that had become spent through its use in the hydrotreatment of distillate feedstock. Samples of spent CENTINEL™ DC-2118 high activity hydroprocessing catalyst were obtained from commercial users of the catalyst. CENTINEL™ DC-2118 is a high activity hydroprocessing catalyst that contains hydrogenation metal components of cobalt and molybdenum that are supported on an alumina support and is marketed by Criterion Catalysts & Technologies of Houston, Tex. The carbon concentration of each Sample A, B, C, D, E, F, G, and H respectively is presented in Table 2 below. Each sample was subjected to a carbon burn by passing air over the sample at a temperature of less than 400° C. The burning conditions were carefully controlled in order to combust only a portion of the carbon on each sample so as to leave a residual amount of carbon on the resulting heat treated spent catalyst, or carbon-reduced catalyst. The carbon concentration of each carbon-reduced catalyst Samples A, B, C, D, E, F, G, and H respectively is presented in Table 2 below. Samples A, B, C, F, G, and H were each subjected to a chelating agent treatment in accordance with the invention. Sample D was not subjected to a chelating agent treatment and Sample E was treated with a chelating agent but was not aged in accordance with the invention. The chelating solution used to treat the carbon-reduced catalyst samples comprised of one (1) part by weight DTPA, 0.11 part by weight ammonium hydroxide, and 10 parts by weight water. The carbon-reduced catalyst samples were impregnated with the chelating solution by a standard incipient wetness procedure by which approximately 98 volume percent of the available pore volume of the carbon-reduced catalyst was filled with the chelating solution. Each sample of the impregnated, carbon-reduced catalyst was then well mixed and allowed to age for an aging time period of two weeks at room temperature in a sealed container to provide an aged catalyst. The aged catalyst samples were then dried in air at a temperature of about 150° C. for a period of about 2 hours. This drying was conducted such that a major portion of the DTPA chelating agent remained on the resulting dried catalyst and that a major portion of the water was removed from the aged catalyst. The dried catalyst was then subjected to a sulfurization step. To sulfurize the dried catalyst, 13.5 parts by weight of elemental sulfur was added to and mixed with 100 parts by weight of dried catalyst. The mixture was then brought to a temperature of about 120° C. and maintained for a period of time sufficient to incorporate the sulfur into the pores of the dried catalyst. Following the sulfur incorporation, an alpha olefin blend containing alpha olefins having from 14 to 30 carbon atoms was incorporated into the pores of the sulfur incorporated, dried catalyst by incipient wetness. The amount of the alpha olefin added to the sulfur incorporated, dried catalyst was sufficient to fill approximately 90 volume percent of the available pore volume. The thus prepared catalyst was then subjected to a heat treatment by heating the samples in flowing air at a temperature of about 260° C. for a period sufficient to provide a dried revitalized catalyst. Each of the Samples A, B, C, F, G, and H (i.e., revitalized samples treated in accordance with the inventive method), Sample D that was not subjected to a chelating agent treatment, and Sample E that was treated with a chelating agent but was not aged in accordance with the invention, was tested for catalytic activity in accordance with the procedure describe in Example 2. EXAMPLE 2 This Example 2 describes the laboratory testing procedure and the feedstocks used to test the catalytic activity of the revitalized catalyst samples described in Example 1 relative to the catalytic activity of fresh CENTINEL™ DC-2118 high activity hydroprocessing catalyst. The properties of the feeds used in the performance of the activity tests are presented in Table 1. To perform the activity tests, 50 cc of the relevant catalyst sample was placed in a test reactor operated under hydrotreating reaction conditions. The reaction conditions included a reaction temperature of about 355° C., total pressure of 600 psia, a feed rate such that the liquid hourly space velocity was 1 hr −1, hydrogen-to-oil ratio of 1200 SCF/bbl, and an operating time of 500 hours. TABLE 1 Feed Properties Used in Activity Tests FEED PROPERTIES FEED A FEED B Sulfur, wt % 1.83 1.65 Nitrogen, ppm 291 243 Aromatics, wt % 12.7 32.8 Density @15.6° C., 0.8534 0.8531 g/cc Bromine Number 15.7 4.1 TBP (by GC) IBP (° F.) 263 320 10% 395 457 50% 561 559 90% 689 648 FBP 870 704 The results of the activity testing described in this Example 2 are presented in Table 2, and FIG. 1 presents a plot of such results. As can be seen from the presentation of the results, particularly as dramatically demonstrated by the graphical presentation of FIG. 1, the restoration of catalytic activity to the spent hydroprocessing catalyst after the chelation treatment is maximized when the carbon content is controlled within a specific range prior to the chelation treatment. TABLE 2 Relative Volumetric Activity of Revitalized Catalyst vs. Percent Carbon WT. % CARBON FEED SAMPLE AFTER BURN RVA USED FRESH N/A 1.00 A and B CATALSYT A 0.14 0.94 A B 1.2 1.00 B C 1.29 0.97 A D 1.29 0.77 A E 1.29 0.78 A F 1.9 0.97 B G 2.02 0.96 B H 3.03 0.86 A EXAMPLE 3 This Example 3 separately presents the results from the activity testing, performed as described in Example 2, of Sample C that was revitalized in accordance with the invention, Sample D that was not subjected to a chelating agent treatment, and Sample E that was treated with a chelating agent but was not aged in accordance with the invention. Table 3 presents the results from this testing. TABLE 3 Data Showing the Effect of Aging on Relative Volumetric Activity of Revitalized Catalyst WT. PERCENT CHELANT SAMPLE CARBON TREATED AGING RVA C 1.29 YES YES 0.97 D 1.29 NO N/A 0.77 E 1.29 YES NO 0.78 The data presented in Table 3 above demonstrate the improvement in catalytic activity that results from the aging of the carbon-reduced catalyst, having a carbon concentration in the optimal range, when it is treated with a chelating agent followed by aging versus treatment with no aging. The data show that there is a significant improvement in the catalytic activity of the carbon-reduced catalyst when it is subjected to a chelation treatment in which the chelant is allowed to age, but there is no improvement in catalytic activity of the carbon-reduced catalyst when it is treated with a chelant with no aging. Reasonable variations, modifications and adaptations of the invention can be made within the scope of the described disclosure and the appended claims without departing from the scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>This invention relates to a method of restoring catalytic activity to a spent hydroprocessing catalyst, the resulting hydroprocessing catalyst and its use in a hydroprocessing process. International publication number WO 01/02092 discloses a process for regenerating a used additive-based catalyst. The regeneration step is carried out by contacting the used additive-based catalyst with oxygen at a temperature of no more than 500° C. The resulting regenerated catalyst more preferably has below 1 wt. % carbon content before it is subjected to a rejuvenation step by being contacted with an organic additive. The method of the publication is limited to additive-based catalysts, and the publication does not recognize a need to control the concentration of carbon on the regenerated catalyst to within a specific range in order to obtain a better benefit from its rejuvenation. In fact, this publication suggests that it is best for the carbon content of the regenerated catalyst to be as low as possible before it is undergoes the rejuvenation treatment. This publication does not disclose that its catalyst rejuvenation step requires the organic additive to remain on the catalyst for an aging period prior to drying. European patent application publication EP 0 541 994 A1 discloses a process for regenerating a hydrogenation catalyst, comprising a support, a Group VI metal and a Group VIII metal, and having coke deposited thereon, by controlling the oxidative burning of the coke so as not to reduce the residual coke content to less than 0.5 weight percent and to control it within the range of from 0.5 to 10.0 weight percent. This publication notes that too severe oxidation conditions can negatively change the pore structure, surface area, and active sites of the catalyst. The publication does not provide experimental data that compares the activity of regenerated catalyst with the activity of the fresh catalyst, but it only presents comparative data for certain physical properties of the two catalysts. Also, nothing is disclosed concerning revitalization of a spent catalyst using chelating agents and the relationship between carbon removal and a chelation treatment. U.S. Pat. No. 6,239,066 B1 discloses a process for improving the activity of a catalyst by treatment thereof with a chelating agent. It is noted that the treatment method can also be used to improve the activity of a spent catalyst. Exemplary data presented in an example show that a used catalyst that has been both regenerated and then treated with ethylene diamine tetra acetic acid (EDTA) has better improved relative volumetric activity (RVA) than the used catalyst that has only been regenerated. There is no mention of carbon levels that are on the used catalyst, or the regenerated catalyst, or the regenerated and treated catalyst. There is an ongoing need to find better methods for restoring the activity of catalysts that have lost activity due to their use, particularly, when the catalyst is a spent high activity hydrotreating catalyst. | <SOH> SUMMARY OF THE INVENTION <EOH>Accordingly, in one inventive method provided is a spent hydroprocessing catalyst having a first carbon concentration exceeding about 3 weight percent. The concentration of carbon on the spent hydroprocessing catalyst is reduced to thereby provide a carbon reduced spent catalyst having a second carbon concentration in the range of from about 0.5 weight percent to about 2.5 weight percent. The reduction of the concentration of carbon on the spent hydroprocessing catalyst is done by contacting under carbon burning conditions the spent hydroprocessing catalyst with a gas comprising oxygen and controlling the amount of carbon removed from the spent hydroprocessing catalyst so as to provide the carbon reduced spent catalyst having the second carbon concentration. The carbon reduced spent catalyst is thereafter treated with a chelating agent to provide a revitalized catalyst. In accordance with another inventive method, catalytic activity of a spent high activity hydroprocessing catalyst having a reduced RVA and a concentration of deposited carbon is restored to a maximized regenerated RVA. This method includes providing a spent high activity hydroprocessing catalyst having the reduced RVA and the concentration of deposited carbon. The spent high activity hydroprocessing catalyst is derived from the use of a high activity hydroprocessing catalyst under hydroprocessing conditions by which carbon is deposited thereon to give the concentration of deposited carbon. The spent high activity hydroprocessing catalyst is heat treated by contacting it with an oxygen-containing gas under carbon burning conditions to thereby provide a heat treated spent high activity hydroprocessing catalyst having a reduced carbon concentration. The reduced carbon concentration is controlled by controlling the carbon burning conditions so as to provide the heat treated spent high activity hydrotreating catalyst having the maximized regenerated RVA. In accordance with yet another invention, provided is a catalyst having restored activity and comprising a spent hydroprocessing catalyst having deposited thereon a deactivating concentration of carbon, wherein a portion of the deactivating concentration of carbon is removed therefrom by the heat treatment of the spent hydroprocessing catalyst in the presence of an oxygen-containing gas to give an optimized concentration of carbon and, thereafter, the thus-heat treated spent hydrotreating catalyst has been subjected to a chelating treatment. The catalyst having restored activity and those catalysts made by the aforementioned methods can be used in a hydroprocessing process comprising contacting the revitalized hydroprocessing catalyst with a hydrocarbon feedstock under hydroprocessing conditions. Other objects and advantages of the invention will become apparent from the following detailed description and appended claims. | 20050119 | 20100413 | 20050721 | 80709.0 | 0 | WIESE, NOAH S | METHOD OF RESTORING CATALYTIC ACTIVITY TO A SPENT HYDROPROCESSING CATALYST, A SPENT HYDROPROCESSING CATALYST HAVING RESTORED CATALYTIC ACTIVITY, AND A HYDROPROCESSING PROCESS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,039,783 | ACCEPTED | Gradient calculating camera board | In a machine vision system utilizing computer processing of image data, an imaging module incorporates the image sensor as well as pre-processing circuitry, for example, for performing a background subtraction and/or a gradient calculation. The pre-processing circuitry may also compress the image information. The host computer receives the pre-processed image data and performs all other calculations necessary to complete the machine vision application, for example, to determine one or more wheel alignment parameters of a subject vehicle. In a disclosed example useful for wheel alignment, the module also includes illumination elements, and the module circuitry provides associated camera control. The background subtraction, gradient calculation and associated compression require simpler, less expensive circuitry than for typical image pre-processing boards. Yet, the pre-processing at the imaging module substantially reduces the processing burden on the host computer when compared to machine vision implementations using direct streaming of image data to the host computer. | 1. An imaging module for use in a system implementing a machine vision application, the imaging module comprising: an image sensor, for imaging a field of view encompassing a target subject of the machine vision application and generating representative image data; a processor, coupled to receive the image data from the image sensor, for calculating gradient information from the image data; and a data communication interface for transmitting the gradient information from the processor to a host implementing the machine vision application. 2-38. (canceled) | RELATED APPLICATION This application claims the benefit of U.S. Provisional Application No. 60/433,997 entitled “Gradient Calculating Camera Board” filed on Dec. 18, 2002, the disclosure of which is entirely incorporated herein by reference. TECHNICAL FIELD The present subject matter relates to a technique for processing image signals for input to a computer or the like, for machine vision and similar applications, which utilizes a gradient calculation and/or a background subtraction. BACKGROUND An increasing variety of industrial applications involve machine vision measurements taken by processing image data from cameras., For example, wheels of motor vehicles may be aligned on an alignment rack using a computer-aided, three-dimensional (3D) machine vision alignment apparatus. In such a technique, one or more cameras of the alignment apparatus view targets attached to the wheels of the vehicle. The cameras form images of the targets, and a computer in the alignment apparatus analyzes the images of the targets to determine wheel position. The computer guides an operator in properly adjusting the wheels to accomplish precise alignment, based on calculations obtained from processing of the image data. Examples of methods and apparatus useful in 3D alignment of motor vehicles are described in U.S. Pat. No. 5,943,783 entitled “Method and apparatus for determining the alignment of motor vehicle wheels;” U.S. Pat. No. 5,809,658 entitled “Method and apparatus for calibrating cameras used in the alignment of motor vehicle wheels;” U.S. Pat. No. 5,724,743 entitled “Method and apparatus for determining the alignment of motor vehicle wheels;” and U.S. Pat. No. 5,535,522 entitled “Method and apparatus for determining the alignment of motor vehicle wheels.” A wheel alignment system of the type described in these references is sometimes called a “3D aligner” or “aligner.” An example of a commercial vehicle wheel aligner is the Visualiner 3D, commercially available from John Bean Company, Conway, Ark., a unit of Snap-on Tools Company. Of course, the 3D wheel aligner discussed above is described here as just one example of a system utilizing machine vision in a commercial application. In a 3D aligner and in other applications involving machine vision, there is a substantial amount of processing required to interpret camera images. In current machine vision systems, such as the 3D aligners, there are two general ways to process the video image signals from the cameras, both of which have limitations or problems. The most common image processing technique in industrial machine vision applications utilizes a dedicated video processing module, comprising hard-wired and other processing devices specifically designed and adapted to process the image data before input of processed results to the host computer. In alignment systems, for example, such a board processes signals from one or more cameras to produce target orientation results or possibly even alignment numbers, for display and/or further processing by the host computer. However, video processing boards often require use of complex, expensive processors to perform all of the necessary calculations required for the image algorithms. The alternative approach to processing image data for machine vision applications involves streaming image data from the camera(s) to an image capture board whose image memory is accessible by the host computer. The host computer, in turn, performs all of the processing of the image data, which would otherwise be done on the dedicated video processing module, to obtain the necessary calculation results. However, the amount of processing required is quite large and imposes a substantial burden on the central processing unit of the host computer. Such intense processing may unacceptably slow down operation of the host computer. If the particular machine vision application requires processing of images from multiple cameras, the amount of the data to be handled and the attendant number of necessary calculations may overwhelm the host computer. SUMMARY Hence a need exists for an enhanced technique for performing the image data processing for machine vision applications in a manner that requires at most a minimal amount of specialized processing hardware and yet does not require the host computer to perform an excessive number of related calculations. As disclosed herein, circuitry associated with the image sensor, typically in a sensor module, performs pre-processing of the data before transmission thereof to a host computer. One image-processing task for machine vision applications involves the identification and accurate measurement of the boundaries of objects in the image. Properties of objects, such as area, centroid, and other relevant parameters may then be determined from these boundary measurements. Such objects are often characterized as groups of pixels having significantly different intensities than surrounding pixels, and their boundaries are at the peak of the gradient of the image. To support such an image-processing task, it is useful to perform a pre-processing at the image module to obtain the gradient of the image. Another image pre-processing operation is background subtraction. In a wheel alignment example, objects of interest in the image are produced by a source of illumination adjacent to the camera. To remove other objects, a background image is acquired by the camera, for example, without this illumination. Then a foreground image, e.g. with illumination present, is acquired. This foreground image has both the objects produced by the illumination and the other objects. A pixel-by-pixel subtraction of the background image from the foreground produces an image containing only the objects of interest. For this subtraction process, an image memory buffers the background image, and a processing device performs the subtraction. If gradient processing is provided, the background subtraction is performed before gradient calculation. If separate devices are used to perform subsequent processing on the pre-processed image data, compression may be used at the imaging module, to reduce the inter-device bandwidth requirements for transmission of the pre-processed data to the host computer. Ideally, these operations (background subtraction, gradient calculation and compression) are performed at the incoming image data rate, so that there are no delays or requirements for additional buffer memory. The concepts disclosed herein alleviate the above noted problems and address the stated needs relating to processing of image data in machine vision applications. One disclosed technique involves gradient calculation in response to image data from one or more image sensors. In a disclosed example, an imaging module includes an image sensor as well as elements for illumination and gain control. The imaging module performs the gradient calculation and may compress the resultant gradient data stream for transmission to a host computer for further processing, for example in a pipelined fashion, at the data rate of the image sensor. The gradient calculation is performed on every pixel. The example does not require foreground image pre-buffering. The resultant gradient data stream significantly reduces the amount of data to be transmitted to the host computer (and thus the transmission bandwidth) as well as the number of subsequent calculations performed by the host computer. Consequently, the connection between the host computer and the module may utilize a simple connection methodology, such as USB 1.0 or 2.0, and the processing performance requirements for the computer can be significantly reduced. However, because of the relative simplicity of the gradient pre-processing, the module does not require as complex (or expensive) hardware as currently available image processing boards. This reduces cost yet leaves the host computer with capacity to run other applications, or accept data from larger numbers of cameras, or both. Another disclosed technique involves performing a background subtraction in response to image data from one or more image sensors. In a disclosed example, an imaging module includes an image sensor as well as elements for illumination and gain control. The imaging module performs the background subtraction and may compress the resultant data stream for transmission to a host computer for further processing. The processor in the exemplary module may also perform a gradient computation, based on the result of the background subtraction. In the disclosed example, the “background” image is taken without illumination, whereas the “foreground” image is taken with illumination. The image data that remains after the background (light off) image is subtracted from the foreground (light on) image corresponds to the elements in the field of view that are illuminated by and highly reflective to the light from the illumination source. Such a subtraction takes out distracting objects, for example, objects not relevant to a wheel alignment application. In the examples, a number of other improvements are contemplated for the imaging module of a vehicle alignment system. In one such improvement, the imaging module includes a field programmable gate array (FPGA) coupled to the image sensor circuit, for pre-processing the digitized images. A communication interface, such as a USB 2.0 interface, sends the pre-processed image data to the host processor. In an example of this arrangement, the USB interface is part of an integrated circuit, which also includes the micro controller of the imaging module. Another improvement in the image sensing module involves providing active cooling, particularly for the image sensor circuit. In the example, a temperature sensor provides feedback data to the micro-controller, which controls a Peltier device or thermoelectric cooler arranged to cool the camera circuit. Yet a further improvement in the image sensing module involves optically isolating the strobe circuit. The module typically comprises an image sensor circuit, an electronic strobe circuit, a controller circuit coupled to the image sensor circuit and the electronic strobe circuit, and a communication interface circuit. At least one optical isolator is coupled to the electronic strobe circuit, for optically isolating the strobe circuit from the other circuits of the image sensing module. The optical isolation of the strobe circuit from the other circuits prevents the power from the strobe circuit feeding back into the logic circuits and damaging the logic circuits. Additional objects, advantages and novel features of the examples will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the accompanying drawings or may be learned by production or operation of the examples. The objects and advantages of the concepts may be realized and attained by means of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The drawing figures depict one or more implementations in accord with the present concepts, by way of example only, not by way of limitations. In the figures, like reference numerals refer to the same or similar elements. FIG. 1 a perspective view of a wheel alignment system utilizing machine vision, which may incorporate the gradient calculating and compression elements into the imaging modules. FIG. 2 is a simplified functional block diagram of an imaging module, which may be used in the machine vision system of FIG. 1. FIG. 3 is a simplified functional block diagram of the image processing elements of the imaging module of FIG. 2. FIG. 4 is a simplified functional block diagram of a personal computer implementation of the host computer of the machine vision system of FIG. 1. FIG. 5 is a functional block diagram of the circuitry of an image sensing module. FIG. 6 is a functional block diagram of an FPGA, which may be used in the module of FIG. 5. FIG. 7 is a functional block diagram of a strobe control, for example, as might be implemented as additional functions in an FPGA DETAILED DESCRIPTION The various examples disclosed herein relate to systems and techniques for implementing machine vision in an enhanced manner by providing an imaging module having an image sensor as well as associated pre-processing circuitry. In the examples, the pre-processing circuitry in the imaging module a background subtraction and/or a gradient calculation. The pre-processing circuitry or other means in the imaging module may also provide data compression for reduced bandwidth communication to a host processor. Reference now is made in detail to the examples illustrated in the accompanying drawings. The concepts discussed herein are applicable in a variety of different types of machine vision systems. For purposes of discussion, it may be helpful to consider a specific example of a machine vision system, such as a 3D aligner as illustrated in FIG. 1, before going into the details of the imaging module. In the example shown, the aligner system 100 consists of three major components. The first of these elements is an illumination and imaging system 102. This portion of the system comprises two imaging modules 110, 112. Each of the imaging modules 110, 112 includes a light emitter or illumination system (typically a strobe). Each of the imaging modules 110, 112 also includes an image sensor, typically in the form of a digital camera. Essentially, each camera forms an image of objects within its field of view, which in operation includes one or more targets; and in response to the image each camera generates digital image data. As discussed more, later, each of the imaging modules 110, 112 includes circuitry for processing of the digital image data to perform the gradient calculations and the compression of the gradient data. Each light emitter takes the form of an array of strobed (flashing) red LEDs mounted around the aperture of one of the cameras. The exemplary system uses high-resolution digital cameras. The imaging modules 110 and 112 are mounted at opposite ends of a horizontal beam 114. In the wheel alignment application, the beam provides desired separation between the modules, to allow the desired view of the vehicle wheels from opposite sides. The height of the beam, and thus the height of the cameras in the modules 110 and 112, may be fixed or adjustable. The structure of the beam 114 and the structure for supporting the beam 114 are not significant for purposes of this discussion. Those skilled in the art will recognize that machine vision applications, including wheel alignment, may use a single imaging module or use more than the two modules 110, 112 shown in the example. The second major element of the aligner 3D system is a set of four passive heads, 118, 120, 122 and 124 for attachment to the vehicle wheels 126, 128 130 and 132. Each head includes a wheel-rim clamp and an attached target object. In the example, each target object has a planar surface with a plurality of visually perceptible, geometrically configured, retro-reflective target elements, which appear as a pattern of reflective circles or dots of different sizes on the planar surface. Examples of target bodies 134 and target elements 136 acceptable for use in wheel alignment applications are described in U.S. Pat. No. 5,724,743. Other target designs may be used for wheel alignment, for example with different visually perceptible target elements 136; and those skilled in the art will recognize that other machine vision applications involve imaging of different types of targets or imaging of object features. In the wheel alignment application, targets 118, 120, 122, 124 are mounted on each of the wheels 126, 128, 130, 132 of the motor vehicle. Each target 118, 120, 120, 124 includes a target body 134, target elements 136, and an attachment apparatus 138. The target elements 136 are positioned on the target body 134. The attachment apparatus 138 attaches the target 118, 120, 120, 124 to wheel 126, 128, 130, 132, respectively. An example of an attachment apparatus is described in U.S. Pat. No. 5,024,001, entitled “Wheel Alignment Rim Clamp Claw” issued to Borner et al. on Jun. 18, 1991, incorporated herein by reference. Of course other mounting arrangements may be used. The beam 114 supporting the imaging modules 110 and 112 has a length sufficient to position the cameras in the modules 110, 112 respectively outboard of the sides of the vehicle to be imaged by the position determination system 100. Also, the beam 114 positions the cameras in the modules 110, 112 high enough above the wheels to ensure that the two targets 118, 120 on the left side of the vehicle are both within the field of view of the left side camera in module 110, and the two targets 122, 124 on the right side of the vehicle are both within the field of view of the right side camera in module 112. The other major element of the aligner system 100 is a programmed computer or host 111, typically a personal computer or similar programmable data processing device. In a typical implementation, the computer 111 includes a processor, a keyboard, a mouse, a printer and a color display monitor, as will be discussed in more detail, later. In the wheel alignment example of machine vision, the computer 111 is programmed to receive and process the compressed image gradient data from the imaging modules 110 and 112. The host computer 111 processes the received data to calculate alignment parameters for a vehicle and to provide a graphical three-dimensional representation of those parameters as a display to a mechanic. In general, the host processing system 111 processes the compressed gradient information to derive positional data regarding position of the visually perceptible target elements from the camera images; and the host processing system 111 processes the positional data to determine one or more wheel alignment parameters of the vehicle under test. The computer 111 also offers a variety of other information useful in adjusting vehicle alignment. The computer also provides the user interface for operation of the system. In operation, once the wheel aligner system 100 has been calibrated in a known manner, a vehicle can be driven onto the rack 140, and, if desired, the vehicle lifted to an appropriate repair elevation. The targets 118, 120, 122, 124, once attached to the wheel rims, are then oriented so that the target elements 136 on the target body 134 face the camera in the respective module 110 or 112. The camera height may be fixed or adjustable to correspond to lift height. The vehicle and model year can then be entered into the computer 111 along with other identifying parameters, such as vehicle VIN number, license number, owner name, etc. To take measurements, the mechanic begins by operating the system 100 to take a first set of images of the targets 118, 120, 122 and 124. The mechanic then rolls the vehicle back a slight distance, up to eight inches; and the system 100 takes another set of images of the targets 118, 120, 122 and 124. Finally, the mechanic rolls the vehicle forward to its initial position, and the system 100 takes more images. For each of the images, the processing in the respective module 110 or 112 forms gradient data, compresses the data and forwards the resultant data to the host computer 111. For example, from the position and orientation of the target in the images taken at the various positions, the computer 111 calculates the actual position and orientation of each wheel axis, including certain alignment parameters such as toe, camber, thrust angle and setback. In the exemplary system 100, one camera is referenced to the other, so that the host computer 111 utilizes a single coordinate system for modeling the vehicle under test. It is not necessary that the supporting rack 140 be level or even that all wheels lie within the same plane. For each vehicle, the computer 111 defines a reference plane that passes through the centers of rotation of the wheels (called “claw points” because they are the center of the points where the claws of the target assembly grip the wheel rims) as determined from the two test images taken at different positions of the wheels. Since one of these claw points may not lie in the plane defined by the other three, some liberties must be taken. For example, for the purpose of aligning the front wheels 126, 130, the computer 111 defines a reference plane as that formed by the measured claw point location of each of the two front wheels and a point midway between the measured claw point locations of the rear wheels 128, 132. Front wheel alignment calculations then are referenced to this individually measured plane. A similar technique may be used to reference measurements and adjustments with respect of the rear wheels. The front wheels 126, 130 of the vehicle may rest on turntables (not shown), so that the mechanic can operate the steering wheel of the vehicle to change the positions of the front wheel during alignment operations. For example, the mechanic will operate the system 100 to take an image of the targets 118, 120, 122 and 124 with the wheels 126, 130 turned to one side. The mechanic then turns the wheels 126, 130 to the other side; and the system 100 takes another image of the targets 118, 120, 122 and 124. From the position and orientation of the front targets 118, 120 in these images taken at the two turned positions, the computer 111 calculates the steering axis about which each front wheel 126 or 130 turns. Once all measurements are complete, the computer 111 generates a visual output of the measured alignment parameters and/or provides data relating to adjustments needed to bring the alignment parameters back to original manufacturer's specifications. The computer 111 stores manufacturers' specified values and tolerances for the alignment parameters, and retrieves the appropriate information based on the make and model information input by the mechanic. The mechanic may take corrective action, for example, by making adjustments and/or replacing worn parts, and then repeat the process to confirm that the corrective action resulted in appropriate alignment of the vehicle wheels. If necessary, the mechanic may repeat one or more steps of correcting alignment and re-testing, until all parameters are within acceptable tolerances. When complete, the system 111 can provide visual displays and/or printouts, for purposes of billings, reports to the customer, etc. The block diagram in FIG. 2 provides a high level illustration of the functional elements of an example of one of the imaging processing modules 110, 112, for use in the wheel alignment type system 100, using machine vision as outlined above relative to FIG. 1. The illustrated module includes an LED array 201, serving as an illuminator, to emit light for desired illumination of the targets of the wheel alignment system. The elements of the module (FIG. 2) may be built on a single circuit board, although in some implementations, the LED array is a separate replaceable component of the module. The illustrated module also includes a high-resolution digital camera 203, which incorporates the machine vision image sensor. A host computer communication interface 205 provides two-way data communications for the components of the imaging module 110 or 112 with the host computer 111 (FIG. 1). The host communications interface 205 conforms to an appropriate data protocol standard and provides a coupling to a desired physical media, to enable data communication to and from the host computer at desired speeds and in a manner desired for the particular installation. In a typical shop installation for wheel alignment, the host communications interface 205 is a USB interface with a USB connector for cable connection to a matching interface in the host computer 111. Of course those skilled in the art will recognize that other data communications interfaces may be used in wheel alignment systems or in other machine vision applications. For example, if it is desirable in a particular application for the user to have a portable terminal, the host may be a laptop or handheld device, in which case it may be advantageous to use an interface 205 facilitating wireless communications with the host. In addition to the LED array 201, the camera 203 and the host communication interface 205, the module includes circuitry 207 for driving the array 201 to emit light. The driver circuit 207 is coupled to the host communication interface 205, to enable the host computer system 111 to instruct the driver circuit 207 when to activate the array 201 and possibly the desired intensity of the illumination. In response to instructions from the host, the driver circuit activates the LED array 201, and when necessary, adjusts the intensity of the light emitted by the array. The module 110 or 112 may also include one or more control circuits 209. Although the control(s) may be incorporated in one or more of the illustrated elements of the module, for ease of discussion, the control 209 is shown as a single logically separate element. The control 209 is responsive to commands or the like received from the host via the communication interface 205, to provide control signals to the various elements in the imaging module 110 or 112. For example, in response to instructions from the host computer, the control 209 can provide control signals to the camera 203 to set the aperture exposure time thereof or to set a gain for the signal processing performed within the camera, so as to increase or decrease the sensitivity and thus the average pixel intensity level of the data output by the camera 203. The control 209 also activates the camera 203 in response to control data from the host computer system 111, received via the host communication interface 205, so as to form images and provide image data at times specified by the host computer system. The control 209 may also provide control signals to the LED driver circuit 207, for example, to control the timing and amount of illumination emitted from the LED array 201. As noted, the control 209 is responsive to commands from the host computer system, hence, the control 209 enables the host to specify when to activate the array 201 and possibly the desired intensity of the illumination. In operation, the camera 203 outputs a digital value of each image pixel based on analog intensity of the sensed light at the point in the image corresponding to the pixel. The value is digitized and read out. To get higher output values, the camera gain is increased, to effectively multiply the output of the CMOS sensor. Alternatively, the aperture (lens iris diameter) is opened or the sensor light collecting time is lengthened, to increase sensitivity and thereby obtain higher-value output data. For a given machine vision application, such as wheel alignment, it is desirable for the target elements or other visible objects of interest to appear as an intensity within a given range, in the camera image. In a system such as that shown, it is possible to adjust several parameters to modify the resultant intensity to bring the target or other object into the desired intensity range. In the example, the adjustable parameters include the intensity of illumination by the LED array 201, the aperture of the camera 203 and the gain of the camera's internal processing circuitry (typically an analog gain). In the wheel alignment example, the computer system 111 sends instructions to modify operation of the module 110 or 112, so target elements appear within the desired intensity range. For example, if the intensity in the camera output data appears too low, the computer system 111 can instruct the camera 203 (through the control 209) to change the opening and/or time of opening to increase exposure or to increase gain in the signal processing within the camera. Alternatively, the computer system 111 can instruct the driver circuit 207 (through the control 209) to drive the LED array 201 to emit at a higher level. In operation, the camera 203 supplies digital image data to the image processing circuitry 211. The image processing circuitry 211 performs gradient calculations on the digital value for each pixel. The resultant gradient data is compressed, for example, using a run length coding technique. Obviously, other data compression schemes may be used. The image processing circuitry 211 supplies the compressed gradient data to the host communication interface 205, for transmission to the host computer system 111. In general, the exemplary image processing circuitry 211 provides background subtraction, gradient calculation, and gradient compression at the image sensor output rate. Foreground image buffering is unnecessary. The circuitry 211 may also implement one or more thresholds to truncate data. The resultant data stream requires significantly lower transmission bandwidth and substantially reduces the amount of processing that must be performed by the host. As discussed in detail later, several functions or parameters of the processing are set or modified by operation of the control 209. Those skilled in the art will recognize that the image processing circuit 211 may be implemented in a variety of different ways, for example using different processing algorithms. It may be helpful, however, to consider a specific example of a image processing circuitry 211, for example, for use in the wheel alignment type machine vision application, in somewhat more detail. FIG. 3 provides a more detailed diagram of the functional elements of a pipelined implementation of the image processing circuitry 211 and shows the connection thereof to the image sensor (camera) 203 and to the host communication interface 205. The pipelined version of the image processing circuitry 211 may be implemented by a processor with memory or as a filed programmable gate array (FPGA), where the processor or FPGA is programmed to perform the data processing functions shown in the drawing. Alternatively, the image processing circuitry 211 may be implemented as discrete logic circuits designed to perform the specific processing functions. The image-sensing device (camera) 203 in the example uses a progressive scan array. The illustrated pipelined image processing circuitry 211 computes sum-of-squares gradient magnitude for each pixel in the array. The circuitry may selectively provide background subtraction and one or more threshold limiting functions. The circuitry also provides data compression. As previously noted, it is at times desirable to subtract background image data. In the example, “background” is an image taken without the illumination from the LED array 201. The “foreground” is an image taken with the LED array 201 turned on. The background (light off) image is subtracted from the foreground (light on) image. The image data that remains corresponds to the elements in the field of view that are illuminated by and highly reflective to the light from the strobe by the LED array 201. This subtraction takes out distracting objects not relevant to the wheel alignment. In present embodiments, use of the subtraction operation is software selectable. By sending appropriate commands to the control 209, the host computer system can tell the module 110 or 114 whether or not to do the background subtract operation. For example, the system 111 may instruct the module to always do the background subtract operation, when speed is not an issue. The computer system 111 may tell the imaging module 110 or 112 to take a background image periodically and determine noise. In this second case, if noise is high, the control 209 turns the background subtract operation on. Also, computer system 111 may turn the background subtraction function off, typically when image capture speed is an issue (although this means that more processing must be performed). To enable the background subtraction, the image processing circuitry 211 includes a memory or other storage element 215 for storing a background image and a subtraction element 217. When turned on via command from the host computer system 111, the background image data is subtracted from the foreground image data. Specifically, a background image (without illumination by LED array 201) is taken and the digital image data from the camera 203 is stored in the memory 215. In response to incoming foreground image data from the sensor 203 (taken with the LED array on), the subtraction element 217 retrieves corresponding pixel data from the memory 215, and subtracts the stored background data from the incoming image data, at the output rate of the camera 203. The subtraction element 217 performs the background subtraction for each pixel in the image array of the sensor/camera 203. The subtraction element 217 may also truncate the results. The data from the background subtraction element 217 then passes through a software selectable threshold function 219. The level of the threshold is set by the control 209, for example in response to an instruction from the host computer system 111, in a manner similar to setting the background subtraction function on/off. The computer system 111 may cause the module 110 or 112 to set the threshold level during operation, or the module can set the threshold as part of its start-up routine. Pixel intensities below this threshold are considered noise and are set to a fixed constant value, typically the threshold value. The truncated data from the threshold device 219 then passes through two sets 220, 221 of three delay lines, to inputs of Sobel X filter 223 and Sobel Y filter 225, respectively. Each Sobel filter essentially computes a gradient for each pixel in a line of the image with regard to eight surrounding pixels. In the example, each image line comprises 1000 pixels. To compute the intensity gradient for each pixel, each filter must have the data for the center pixel and the data for the eight pixels surrounding the center pixel. For a given line of the image, each filter, therefore, must have the data for the line currently being processed as well as the data for the immediately preceding line and the immediately following line. During any given cycle, each filter 223, 225 receives the current data value n as well as values from two previous lines (n−1, n−2). Hence, the delays 220, 221 provide first line, second line and third line, so that each filter 223 or 225 has enough data at the time to compute the gradient values for the second line of pixels from the image (n−1). By inputting three lines to each filter and processing the pixel data for those lines, the implementation does not need to buffer data for an entire image, and the processing circuitry 211 can perform the gradient calculations live in real time at the output rate of the image sensor 203. The filter 223 calculates the Sobel X (SX) gradient magnitude for each respective pixel in the array. Similarly, the filter 225 calculates the Sobel Y (SY) gradient magnitude for each respective pixel in the array. The desired gradient magnitude is the sum of the squares of these two values (SX and SY). One embodiment for obtaining the squares of these values is by looking up the squared values in tables indexed by the un-squared values. The embodiment of pipelined image processing circuitry shown in 211 includes memories 227, 229 storing such lookup tables. The data from the Sobel X filter 223 is used as an input to memory 227 to lookup the square (SX2) of the Sobel X (SX) gradient value. Similarly, the data from the Sobel Y filter 225 is used as an input to memory 229 to lookup the square (SY2) of the Sobel Y (SY) gradient value. Another embodiment (not shown) could use multiplying devices to produce these squares. A processing element 231 receives the squared data. This element 231 first performs an addition to compute the sum of the squares (SX2+SY2) of the X and Y gradient data. The processing element 231 then shifts and performs a thresholding operation on the sum of squares data to clip the shifted data to conform to the maximum magnitude for each output pixel. The magnitude (number of bits) and/or the threshold level may be set in software by the control 209, in a manner analogous to that of the background subtraction (at 217) and/or the first threshold (at 219). The Sobel filtering and sum of squares gradient calculations may be performed in discrete hardware using commercially available chips or programmed into a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC). The pipelined image processing circuitry 211 also includes a compression engine. A variety of different compression schemes may be used. In this example, compression engine is a run length encoder 233. Those skilled in the art will recognize that other forms of compression may be used along or in combination with run length encoding. In this example, the encoder 233 performs run length encoding (RLE) on the sum of squares data (SX2+SY2) output by the processing element 231 after the shifting and threshold processing. Those skilled in the art will recognize that other data compression techniques may be used. The run length encoder 233 supplies the compressed gradient data to the host communication interface 205, for transmission over the link to the host computer system 111. The host computer system 111 decompresses the received data stream, essentially to reverse the run length encoding and thereby recover the gradient data. Starting from the gradient data, the computer system 111 performs calculations based on the edges of the imaged target elements (dots) as defined by the gradient maxima, to find the centroids of these target elements (dots). The computer 111 uses these centroids to determine the angle/position of the targets in space in each captured image. Then, the computer uses that information to calculate wheel alignment. The image processing formulas are the same as in earlier wheel alignment systems, except that instead of doing much of the calculation on the image processing board or entirely in the host, the imaging module does only the gradient, and the host performs the remaining computations. Detailed discussions of the computations, for a wheel alignment application, are discussed in several of the cited patents. A host system 111 may be implemented on a specifically designed processing system, but in the example, it is implemented by a general-purpose computer controlled by software programming. Of course any of a number of different types of computer may be used, for wheel alignment or other machine vision application, however, the example utilizes a device within the class commonly referred to as a personal computer or “PC.” Although those familiar with the machine vision art and/or the data processing art will generally be familiar with such computers and their associated software, it may be helpful to summarize the structural and functional aspects thereof as they might relate to the wheel alignment example of FIG. 1. FIG. 4 is a functional block diagram of a PC or workstation type implementation of a host computer system 251, which may serve as the host computer 111. In such an application, one function of the system 251 is to process compressed gradient image data from the camera modules to determine wheel alignment parameters. The system may run a number of other programs that are useful to the mechanic and/or other personnel in the auto shop. The exemplary computer system 251 contains a central processing unit (CPU) 252, memories 253 and an interconnect bus 254. The CPU 252 may contain a single microprocessor, or may contain a plurality of microprocessors for configuring the computer system 252 as a multi-processor system. The memories 253 include a main memory, a read only memory, and mass storage devices such as various disk drives, tape drives, etc. The main memory typically includes dynamic random access memory (DRAM) and high-speed cache memory. In operation, the main memory stores at least portions of instructions and data for execution by the CPU 252. The mass storage may include one or more magnetic disk or tape drives or optical disk drives, for storing data and instructions for use by CPU 252. For a PC type implementation, for example, at least one mass storage system 255 in the form of a disk drive or tape drive, stores the operating system and application software as well as data. The mass storage 255 within the computer system 251 may also include one or more drives for various portable media, such as a floppy disk, a compact disc read only memory (CD-ROM), or an integrated circuit non-volatile memory adapter (i.e. PC-MCIA adapter) to input and output data and code to and from the computer system 251. The system 251 also includes one or more input/output interfaces for communications, shown by way of example as an interface 259 for data communications. For purposes of the wheel alignment application, the interface 259 provides two-way data communications with one or more of the imaging modules 110, 112. For example, the interface 259 may be a USB hub providing two or more ports for USB cable links to/from the imaging modules 110, 112. Although not shown, another communication interface may provide communication via a network, if desired. Such an additional interface may be a modem, an Ethernet card or any other appropriate data communications device. The physical links to and from the communication interface(s) may be optical, wired, or wireless. For example, in a typical wheel aligner application, the imaging modules typically connect via USB cables. However, infrared, RF, and broadband wireless technologies may be used for these links. Any external communications may use hard wiring or wireless technologies. The computer system 251 may further include appropriate input/output ports 256 for interconnection with a display 257 and a keyboard 258 serving as the respective user interface. For example, the computer may include a graphics subsystem to drive the output display 257. The output display 257 may include a cathode ray tube (CRT) display or liquid crystal display (LCD). Although not shown, the PC type system 111 typically would include a port for connection to a printer. The input control devices for such an implementation of the system 251 would include the keyboard 258 for inputting alphanumeric and other key information. The input control devices for the system 251 may further include a cursor control device (not shown), such as a mouse, a trackball, stylus, or cursor direction keys. The links of the peripherals 257, 258 to the system 251 may be wired connections or use wireless communications. The computer system 251 typically runs a variety of applications programs and stores data, enabling one or more interactions via the user interface, provided through elements such as 257 and 258 to implement the desired processing. For machine vision applications, the programming will include appropriate code to process the compressed gradient image data to produce the desired machine vision results. For example, when used to implement the host computer 111 for the wheel alignment system the programming enables the device 251 to process the compressed gradient image data to determine the desired alignment parameters. The host 111 will typically run an application or shell specifically adapted to provide the user interface for input and output of desired information for alignment and related services. As noted, because it is a general purpose system, the device 251 may run any one or more of a wide range of other desirable application programs, some of which may involve machine vision but many of which may not. The components contained in the computer systems 251 are those typically found in general purpose computer systems used as servers, workstations, personal computers, network terminals, and the like. In fact, these components are intended to represent a broad category of such computer components that are well known in the art. At various times, the relevant programming for the machine vision processing and any related application(s) such as the wheel alignment application may reside on one or more of several different media. For example, the programming may be stored on a hard disk and loaded into RAM for execution. The programming also may reside on or be transported by other media for uploading into the system 251, to essentially install the programming. Hence, at different times all or portions of the executable code or data for any or all of these software elements may reside in physical media or be carried by electromagnetic media or be transported via a variety of different media to program the particular system. As used herein, terms such as computer or machine “readable medium” therefore refer to any medium that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical or magnetic disks, such as any of the storage devices in the computer 251 of FIG. 4. Volatile media include dynamic memory, such as main memory. Transmission media include coaxial cables; copper wire and fiber optics, including the wires that comprise a bus within a computer system. Transmission media can also take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer can read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution. The following is a discussion of the circuitry of an example of the imaging module, specifically the camera board and an FPGA used for the pre-processing in the camera board. Exemplary Circuit for the Camera Board The embodiment of FIG. 5 usess a combined Controller/USB interface in the form of an integrated circuit (U2), whose functions include a micro controller and a USB2.0 interface. The USB interface can be configured to perform with minimal interaction with the micro controller. The micro controller is used to configure and control the camera and image processing circuits, to control cooling circuits, and provide diagnostic information. Also associated with the micro controller are two nonvolatile memory circuits (U1 and U3). U1 is used to store program code, currently a bootloader for the micro controller. U3 is used to store calibration/security data associated with the camera assembly. In this example, the camera (U4) is a CMOS image array with integrated analog to digital converter. The camera chip is configured for a region of interest (ROI) within the field of view, gain, and timing via the I2C bus from the Controller/USB (U2). Image acquisition is triggered from a single line (referred to as ‘FREX’) routed through the FPGA. The pre-processing functions are implemented by a circuit block consisting of a field programmable gate array (FPGA) (U5) and three static random access memory (SRAM) chips (U6, U7, U8) performing the functions of Background Subtraction, Gradient Processing, and Data Reduction/Compression, as discussed in detail above. This circuit (U5) is configured by the controller and thereafter autonomously processes an image into gradient data for transmission. Image acquisition is triggered by the controller driving a START line (not separately shown for convenience). The strobe (S) is activated as long as the line is high. When START transitions low a frame is requested from the camera. The first frame or “foreground image” is stored in SRAM memory. A second frame is requested and this “background image” is subtracted from the first image. The difference data is then processed via X and Y Sobel filters whose outputs are squared and then summed to provide gradient data. This data is then reduced to provide only data points in regions that have gradient above a threshold set by the controller. Attention is directed to the discussion of FIG. 3, above. The FPGA (U5) controls the taking of the second (background) image without further intervention from the microcontroller (U2). The FPGA (U5) also provides the pixel intensity summation data to the microcontroller (U2) to facilitate image intensity control. The present example of the imaging modules (FIG. 5) incorporates active cooling of the electronic circuitry, particularly that of the camera (U4). The primary cooling components are temperature sensor (U10), a Peltier device or thermoelectric cooler (TEC) (U12), and the drive circuits of a D/A (U9) and transistor (Q2). The temperature sensor U10 supplies the controller circuit with digital data of the temperature via the I2C bus. The controller sets the drive level for the TEC cooler (U12). The driver circuit for the TEC is a digital to analog converter U9 on the I2C bus, which drives the base of a PNP transistor Q2. Temperature control is done via software in the controller/USB device (U2). An earlier design was done with temperature control being accomplished with an autonomous circuit using a temperature sensitive resistor (PTC) to regulate the current from the base of the driving transistor. This circuit was replaced with the described digitally controlled circuit to allow the system to monitor the temperature of the camera and to achieve better and more flexible temperature control. For power, the voltages supplied to the board are 12V for the strobe (S) and 5V which is regulated down to 1.8V and 3.3V via a dual switching regulator in the buck configuration. The 5V line is also used to supply the cooling circuit. The strobe control circuit (SC) is a current regulated switch. The entire strobe circuit is optically isolated from the rest of the board. There is also a circuit to drain the energy from the strobe circuit when power is removed from the board. The primary circuit elements are a PNP transistor (Q3), a sense resistor (R25), a comparison resistor (R23), and an amplifier (U15). The transistor Q3 controls the current passed to the strobe. The voltage drop across the sense resistor R25 and the voltage drop across the comparison resistor R23 are compared and amplified by the amplifier and used to drive the Q3 transistor base. The strobe is turned on/off by gating the current through the comparison resistor (R23). This is accomplished by using the optoisolator U16. Another resistor (R27) is added in series with the comparison resistor and a diode (D26) is placed in parallel with this pair of resistors (R23 R27) to provide some immunity from power supply and on/off gate voltage variations. R24 is used to reduce the current requirements for the comparison circuit. R21 and R22 are used to force the amplifier/transistor to shut off when current through the comparison resistor is shut off. R26 and C75 are used as a snubber circuit to reduce ringing and electromagnetic interference. The optical isolation of the strobe circuit from the other circuits prevents the power from the strobe circuits feeding back into the logic circuits and damaging them. This allows “hot plugging” the circuits without damage. It also reduces the problems of surge currents in the strobe affecting the image accuracy and operation of the other circuits. The circuit around Q1 is used to drain the energy storage capacitor C74. When the 5V supply is no longer active the optoisolator U14 will turn off. R16 will pull the base of Q1 high and Q1 will gate current from C74 through R17 and R18. R17 and R18 were paralleled here to accommodate worst case power dissipation. This exemplary circuit enables configuration of the hardware (FPGA) from the host, as a regular function. This allows us to change the hardware configuration to perform special processing at will. The FPGA offers the option to use the same physical hardware and change its configuration to suit the needs of the application. This makes the camera system much more flexible. The configuration can be changed to aid in performing diagnostics for example. Additionally, the same physical camera could have one configuration for wheel alignment and then be reconfigured via software to do edge detection for frame/body work. Should the image processing algorithms change, it is possible to communicate the new configuration data as part of a software update. Exemplary FPGA for the Camera Board (Functional Description) This description will follow the data path of the FPGA. 10 bits of camera data are fed through a multiplexer such that 8 bits are selected for processing. If any of the camera bits of higher order than those selected for processing is set, the 8 bit value is set to 255. These 8 bits are latched into a FIFO with the pixel clock supplied by the camera chip. This same pixel clock is used to increment row/column counters for the control section to determine when a frame is completed. The actual processing section is divided into four primary sections: Sum, Input, Gradient, and Compress. These sections are driven with a 48 MHz clock, which is twice the maximum data rate of the camera. FIG. 6 is a block diagram of these functions implemented/performed in the FPGA. Sum: The sum section consists of an adder that adds the 8 bits of camera data during the strobed frame to a 32-bit register. This register is cleared at start of frame. The value in the register may be read out via the serial data line. The purpose of this section is to supply data to the processor to allow adjustment of the strobe duration. This section runs in parallel with the Input section. Input: This section performs the background subtraction, background threshold, and arranges the input into three rows of data for output to the gradient section. This section takes the 8 bits of camera data. The first frame of camera data is assumed to be a strobed image. This data is stored in frame memory off the FPGA chip. The second frame coming in is assumed to be the background image. As each byte is delivered, it is subtracted from the stored value for that pixel in the frame memory and the 8 result is compared to an 8 bit register value set by the processor. This 8-bit register is referred to as the background threshold. If the result of the subtraction is negative or less than the background threshold, a zero is passed through. These limited values are passed through two row FIFOs such that three output values are made available to the next section. These values are labeled R0, R1, and R2. R0 is the top row, R1 the middle row, and R2 the bottom row. The processing and FIFOs result in this section having a pipeline delay of X+(2*RowWidth). The items 220 and 221 in FIG. 3 are essentially combined and only the two FIFOs are required in the Input section of of the FPGA in FIG. 6. The use of the two FIFOs is cheaper than six. Gradient: The gradient section calculates sum of the squared X and Y Sobel values for a given pixel. This section takes in three row values as output from the Input section. These three values are each clocked through two registers such that 9 values are available for processing. These values can be referred to as X0Y0 through X2Y2. The processing performed can be represented as: topLbotR=X1Y1−X3Y3; // signed 9 bit result topMbotM=(X2Y1−X2Y3) * 2; // signed 10 bit result botLtopR=X1Y3−X3Y1; // signed 9 bit result midLmidR=(X3Y2−X1Y2) * 2; // signed 10 bit result X2=topLbotR+botLtopR; // signed 10 bit result X2=X2+midLmidR; // signed 11 bit result X2=X2*X2; // signed 22 bit result Y2=topLbotR−botLtopR; // signed 10 bit result Y2=X2+topMbotM; // signed 11 bit result Y2=Y2*Y2; // signed 22 bit result RESULT=X2+Y2; // signed 23 bit result 8 bits of RESULT are then selected through a multiplexer for output. If any RESULT bits of higher order than those selected is set, then the output will be set to 255. Pipeline delay of Gradient is x clocks. Compression: This section compresses the data stream. Input is a stream of 8 bit words. The input stream is fed through a 4 FIFOs such that we have 5 row inputs. These five inputs are compared to a Compression Threshold value set by the processor. If any of these five row inputs is over threshold, the two preceding values, the current value, and two following values from the middle (row 3) are to be sent. If the next set of row inputs is over threshold, then the two values following it are to be sent. The result is that all values over threshold and their adjacent values within a radius of two are sent. All values not to be sent are considered 0. Any time a 0 is encountered the next byte is a skip count. Skip count represents the number of additional bytes of zero value. The skip count will not extend beyond the frame. A zero that is to be sent due to proximity to a value over threshold may be sent as a 1. If the last byte of the frame is a zero and the skip count following it would be zero, that byte may be sent as a 1. A single byte of data below threshold MAY be sent as a 1. The output of the compression section feeds a FIFO that is read by the processor's GPIF (General Purpose Interface) section. The GPIF section provides an interface to certain types of micro controller that may be used as the controller 209. If the compression section attempts to write into the FIFO when it is full then the nOVERFLOW line will toggle and the FPGA will halt processing. The EMPTY line will be asserted if there is no data for the GPIF to read. The processing in the embodiment of FIGS. 5 and 6 is not entirely pipelined in nature. The camera generates data at a rate faster than it could be shipped via USB, and system performance is better if the FPGA pipelines just the background subtract and then buffers the subtracted image. As noted earlier, the FPGA can be dynamically reconfigured to allow the hardware to meet other image processing requirements. For example, it is also possible to implement the strobe control function in the FPGA. The FPGA can limit the duty cycle of the strobe to prevent overheating. The timing of the strobe relative to the camera framing can be more tightly controlled. The timing requirements of the background (dark) frame may be more precisely matched to the foreground (illuminated) frame. The FPGA could also stream multiple processed frames without further intervention. FIG. 7 is a functional block diagram illustrating the logic of a strobe control circuit, which may be implemented as a separate circuit or implemented as additional programmed functions of the FPGA. As shown, the processor sets the strobe width (or time period) via an I2C signal, just as it sets the other thresholds and settings of the FPGA. A Start signal activates the Strobe and starts counter 1 after a preset delay. The delay is used to make the transitions of FREX fall within certain parameters required by the camera chip. The output of counter 1 is compared to the strobe width, and when they are equal the strobe output and FREX outputs fall telling the camera chip to start transmitting frame data. The output of compare 3 also starts counter 3. Counter 3 has its clock divided by 4. After 4 strobe periods, the done signal is presented to the processor so that the duty cycle of the strobe will be 1 in 5 (on one strobe period and then off for 4). When the foreground frame is processed, the background signal is activated raising FREX but not the Strobe signal. Counter 2 is compared with the strobe width, and when they are equal, FREX falls telling the camera chip to start transmitting the background image. Those skilled in the art will recognize that the concepts disclosed herein have wide applicability and may admit of a wide range of modifications. For example, a machine vision technique such as outlined above could be implemented for other types of alignment processes (e.g. wing alignment) as well as for a wide range of other types of machine vision applications, such as product assessment in a manufacturing operation, code or character recognition in document or mail piece handling systems, etc. While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the technology disclosed herein may be implemented in various forms and examples, and that they may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all modifications and variations that fall within the true scope of the advantageous concepts disclosed herein. | <SOH> BACKGROUND <EOH>An increasing variety of industrial applications involve machine vision measurements taken by processing image data from cameras., For example, wheels of motor vehicles may be aligned on an alignment rack using a computer-aided, three-dimensional (3D) machine vision alignment apparatus. In such a technique, one or more cameras of the alignment apparatus view targets attached to the wheels of the vehicle. The cameras form images of the targets, and a computer in the alignment apparatus analyzes the images of the targets to determine wheel position. The computer guides an operator in properly adjusting the wheels to accomplish precise alignment, based on calculations obtained from processing of the image data. Examples of methods and apparatus useful in 3D alignment of motor vehicles are described in U.S. Pat. No. 5,943,783 entitled “Method and apparatus for determining the alignment of motor vehicle wheels;” U.S. Pat. No. 5,809,658 entitled “Method and apparatus for calibrating cameras used in the alignment of motor vehicle wheels;” U.S. Pat. No. 5,724,743 entitled “Method and apparatus for determining the alignment of motor vehicle wheels;” and U.S. Pat. No. 5,535,522 entitled “Method and apparatus for determining the alignment of motor vehicle wheels.” A wheel alignment system of the type described in these references is sometimes called a “3D aligner” or “aligner.” An example of a commercial vehicle wheel aligner is the Visualiner 3D, commercially available from John Bean Company, Conway, Ark., a unit of Snap-on Tools Company. Of course, the 3D wheel aligner discussed above is described here as just one example of a system utilizing machine vision in a commercial application. In a 3D aligner and in other applications involving machine vision, there is a substantial amount of processing required to interpret camera images. In current machine vision systems, such as the 3D aligners, there are two general ways to process the video image signals from the cameras, both of which have limitations or problems. The most common image processing technique in industrial machine vision applications utilizes a dedicated video processing module, comprising hard-wired and other processing devices specifically designed and adapted to process the image data before input of processed results to the host computer. In alignment systems, for example, such a board processes signals from one or more cameras to produce target orientation results or possibly even alignment numbers, for display and/or further processing by the host computer. However, video processing boards often require use of complex, expensive processors to perform all of the necessary calculations required for the image algorithms. The alternative approach to processing image data for machine vision applications involves streaming image data from the camera(s) to an image capture board whose image memory is accessible by the host computer. The host computer, in turn, performs all of the processing of the image data, which would otherwise be done on the dedicated video processing module, to obtain the necessary calculation results. However, the amount of processing required is quite large and imposes a substantial burden on the central processing unit of the host computer. Such intense processing may unacceptably slow down operation of the host computer. If the particular machine vision application requires processing of images from multiple cameras, the amount of the data to be handled and the attendant number of necessary calculations may overwhelm the host computer. | <SOH> SUMMARY <EOH>Hence a need exists for an enhanced technique for performing the image data processing for machine vision applications in a manner that requires at most a minimal amount of specialized processing hardware and yet does not require the host computer to perform an excessive number of related calculations. As disclosed herein, circuitry associated with the image sensor, typically in a sensor module, performs pre-processing of the data before transmission thereof to a host computer. One image-processing task for machine vision applications involves the identification and accurate measurement of the boundaries of objects in the image. Properties of objects, such as area, centroid, and other relevant parameters may then be determined from these boundary measurements. Such objects are often characterized as groups of pixels having significantly different intensities than surrounding pixels, and their boundaries are at the peak of the gradient of the image. To support such an image-processing task, it is useful to perform a pre-processing at the image module to obtain the gradient of the image. Another image pre-processing operation is background subtraction. In a wheel alignment example, objects of interest in the image are produced by a source of illumination adjacent to the camera. To remove other objects, a background image is acquired by the camera, for example, without this illumination. Then a foreground image, e.g. with illumination present, is acquired. This foreground image has both the objects produced by the illumination and the other objects. A pixel-by-pixel subtraction of the background image from the foreground produces an image containing only the objects of interest. For this subtraction process, an image memory buffers the background image, and a processing device performs the subtraction. If gradient processing is provided, the background subtraction is performed before gradient calculation. If separate devices are used to perform subsequent processing on the pre-processed image data, compression may be used at the imaging module, to reduce the inter-device bandwidth requirements for transmission of the pre-processed data to the host computer. Ideally, these operations (background subtraction, gradient calculation and compression) are performed at the incoming image data rate, so that there are no delays or requirements for additional buffer memory. The concepts disclosed herein alleviate the above noted problems and address the stated needs relating to processing of image data in machine vision applications. One disclosed technique involves gradient calculation in response to image data from one or more image sensors. In a disclosed example, an imaging module includes an image sensor as well as elements for illumination and gain control. The imaging module performs the gradient calculation and may compress the resultant gradient data stream for transmission to a host computer for further processing, for example in a pipelined fashion, at the data rate of the image sensor. The gradient calculation is performed on every pixel. The example does not require foreground image pre-buffering. The resultant gradient data stream significantly reduces the amount of data to be transmitted to the host computer (and thus the transmission bandwidth) as well as the number of subsequent calculations performed by the host computer. Consequently, the connection between the host computer and the module may utilize a simple connection methodology, such as USB 1.0 or 2.0, and the processing performance requirements for the computer can be significantly reduced. However, because of the relative simplicity of the gradient pre-processing, the module does not require as complex (or expensive) hardware as currently available image processing boards. This reduces cost yet leaves the host computer with capacity to run other applications, or accept data from larger numbers of cameras, or both. Another disclosed technique involves performing a background subtraction in response to image data from one or more image sensors. In a disclosed example, an imaging module includes an image sensor as well as elements for illumination and gain control. The imaging module performs the background subtraction and may compress the resultant data stream for transmission to a host computer for further processing. The processor in the exemplary module may also perform a gradient computation, based on the result of the background subtraction. In the disclosed example, the “background” image is taken without illumination, whereas the “foreground” image is taken with illumination. The image data that remains after the background (light off) image is subtracted from the foreground (light on) image corresponds to the elements in the field of view that are illuminated by and highly reflective to the light from the illumination source. Such a subtraction takes out distracting objects, for example, objects not relevant to a wheel alignment application. In the examples, a number of other improvements are contemplated for the imaging module of a vehicle alignment system. In one such improvement, the imaging module includes a field programmable gate array (FPGA) coupled to the image sensor circuit, for pre-processing the digitized images. A communication interface, such as a USB 2.0 interface, sends the pre-processed image data to the host processor. In an example of this arrangement, the USB interface is part of an integrated circuit, which also includes the micro controller of the imaging module. Another improvement in the image sensing module involves providing active cooling, particularly for the image sensor circuit. In the example, a temperature sensor provides feedback data to the micro-controller, which controls a Peltier device or thermoelectric cooler arranged to cool the camera circuit. Yet a further improvement in the image sensing module involves optically isolating the strobe circuit. The module typically comprises an image sensor circuit, an electronic strobe circuit, a controller circuit coupled to the image sensor circuit and the electronic strobe circuit, and a communication interface circuit. At least one optical isolator is coupled to the electronic strobe circuit, for optically isolating the strobe circuit from the other circuits of the image sensing module. The optical isolation of the strobe circuit from the other circuits prevents the power from the strobe circuit feeding back into the logic circuits and damaging the logic circuits. Additional objects, advantages and novel features of the examples will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the accompanying drawings or may be learned by production or operation of the examples. The objects and advantages of the concepts may be realized and attained by means of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims. | 20050124 | 20060704 | 20050616 | 92654.0 | 1 | FULTON, CHRISTOPHER W | GRADIENT CALCULATING CAMERA BOARD | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,039,833 | ACCEPTED | Stencil printing machine | A stencil printing machine includes: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies ink to the surface of the outer peripheral wall from the ink supply port; a pressure roller which presses a print medium fed thereto to the outer peripheral wall; and a first cap device capable of closing the ink supply port. Moreover, the stencil printing machine further includes: an ink return device which has an ink return port on the outer peripheral wall, and returns the ink which flows into the ink return port; and a second cap device capable of closing the ink return port. | 1. A stencil printing machine, comprising: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies an ink to the surface of the outer peripheral wall from the ink supply port; a pressure roller which presses a print medium fed thereto to the outer peripheral wall; and a first cap device which shifts between a closing position of closing the ink supply port and an opening position of opening the ink supply port. 2. The stencil printing machine according to claim 1, further comprising: an ink return device which has an ink return port on the outer peripheral wall, and returns the ink which flows into the ink return port; and a second cap device which shifts between a closing position of closing the ink return port and an opening position of opening the ink return port. 3. The stencil printing machine according to claim 1, wherein the first cap device comprises: a drive source fixed to a machine body side; and a first cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. 4. The stencil printing machine according to claim 2, wherein the second cap device comprises: a drive source fixed to a machine body side; and a second cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing machine which conveys a print medium while pressing the print medium to a drum on which a stencil sheet is mounted, and transfers ink oozing from perforations of the stencil sheet onto the print medium. 2. Description of the Related Art As a conventional printing method of a stencil printing machine, there are an inner press method (refer to Japanese Patent Laid-Open Publication No. Hei 7-132675 (published in 1995)) and an outer press method (refer to Japanese Patent Laid-Open Publication No. 2001-246828). The inner press method is briefly described. As shown in FIG. 1, a drum 100 and a back press roller 101 are provided, and the drum 100 and the back press roller 101 are provided so as to be freely rotatable in a state where outer peripheral surfaces thereof are partially made substantially adjacent to each other. A stencil clamping portion 100a which clamps a tip end of a stencil sheet 104 is provided on the outer peripheral surface of the drum 100, and an outer peripheral wall other than the stencil clamping portion 100a is formed of a screen 102 which is flexible and ink permeable. An ink supply mechanism 105 is provided inside the drum 100. As shown in FIG. 2, this ink supply mechanism 105 includes an inner press roller 106 which is an ink supply roller, and the inner press roller 106 is provided on a roller support member 107 so as to be freely rotatable. The inner press roller 106 is configured to be shiftable between a press position where the roller support member 107 is energized in a direction of an arrow a of FIG. 2 to press an inner peripheral surface of the screen 102 and a standby position where the roller support member 107 is rotated in a direction of an arrow b of FIG. 2 to be spaced from the inner peripheral surface of the screen 102. The inner press roller 106 is set at the press position when a print sheet 111 passes therethrough, and otherwise, set at the standby position. Moreover, the inner press roller 106 has a function to apply printing pressure from an inner periphery side of the screen 102. The roller support member 107 is supported so as to be freely rotatable about a support shaft 108, and a doctor roller 109 and a drive rod 110 are individually provided on the roller support member 107. The doctor roller 109 has a cylindrical shape, and is fixed to the roller support member 107 at a position close to the inner press roller 106. The drive rod 110 is supported on the roller support member 107 so as to be freely rotatable, and is placed in an upper space composed of outer peripheral surfaces of the inner press roller 106 and the doctor roller 109 on sides thereof adjacent to each other. Ink 103 is supplied from an ink supply unit (not shown) to the upper space. Next, printing operations are schematically described in order. The stencil sheet 104 on which a perforated image is formed is attached onto an outer peripheral surface of the screen 102. Then, during a printing mode, the drum 100 and the back press roller 101 are rotated in synchronization with each other in directions shown in arrows in FIG. 1, and the print sheet 111 is conveyed between the drum 100 and the back press roller 101. When the print sheet 111 is fed, the inner press roller 106 presses the screen 102, and the inner press roller 106 rotates following the drum 100 in such a pressing state. The ink 103 having passed through a gap between the inner press roller 106 and the doctor roller 109 is adhered onto the outer peripheral surface of the inner press roller 106, and the ink 103 thus adhered is sequentially supplied to an inner surface of the screen 102 by the rotation of the inner press roller 106. Moreover, when the inner press roller 106 presses the screen 102, the screen 102 swells out to the outer periphery side thereof by pressing force at this time, and the screen 102 is put into a press-contact state with the back press roller 101. Then, the print sheet 111 conveyed between the drum 100 and the back press roller 101 is conveyed while being brought into press contact with the screen 102 and the stencil sheet 104 in between the inner press roller 106 and the back press roller 101. By press-contact force at this time, the ink 103 on the screen 102 side is transferred to the print sheet 111 from perforations of the stencil sheet 104, and an ink image is printed on the print sheet 111. The outer press method is briefly described. As shown in FIG. 3, a drum 120 is provided. A stencil clamping portion 120a which clamps the tip end of the stencil sheet 104 is provided on an outer peripheral surface of this drum 120, and an outer peripheral wall 120b other than the stencil clamping portion 120a is formed of an ink permeable member with a porous structure. An ink supply mechanism 125 is provided inside the drum 120. The ink supply mechanism 125 includes a squeegee roller 126 supported so as to be freely rotatable, and a doctor roller 127 placed adjacent to the squeegee roller 126. Ink 128 accumulates in an outer peripheral space surrounded by the squeegee roller 126 and the doctor roller 127. The ink 128 adhered onto the outer periphery of the rotating squeegee roller 126 passes through a gap between the squeegee roller 126 and the doctor roller 127, and thus only the ink 128 with a predetermined film thickness is adhered onto the squeegee roller 126, and the ink 128 with the predetermined film thickness is supplied to an inner surface of the outer peripheral wall 120b. Moreover, a pressure roller 130 is provided at a position opposite to the squeegee roller 126, which is also an outside position of the drum 120. The pressure roller 130 is configured to be shiftable between a press position of pressing the outer peripheral wall 120b of the drum 120 and a standby position of being spaced from the outer peripheral wall 120b of the drum 120. The squeegee roller 126 is fixed to a support member which supports the outer peripheral wall 120b of the drum 120 so as to be freely rotatable, and an outer peripheral surface of the squeegee roller 126 and the inner peripheral surface of the outer peripheral wall 120b of the drum 120 are brought into a state of being slightly spaced from one another in a state where the outer peripheral wall 120b of the drum 120 is not pressed by the pressure roller 130. When the outer peripheral wall 120b of the drum 120 is pressed by the pressure roller 130, the outer peripheral wall 120b of the drum 120 is bent, and thus the outer peripheral surface of the squeegee roller 126 and the inner peripheral surface of the outer peripheral wall 120b of the drum 120 are brought into contact with each other. Next, printing operations are schematically described in order. The stencil sheet 104 on which the perforated image is formed is attached onto an outer peripheral surface of the outer peripheral wall 120b of the drum 120. Then, during the printing mode, the outer peripheral wall 120b of the drum 120 is rotated in a direction shown by an arrow in FIG. 3, and the print sheet 111 is fed between the drum 120 and the pressure roller 130. When the print sheet 111 is fed, the pressure roller 130 presses the outer peripheral wall 120b of the drum 120, and the outer peripheral wall 120b is shifted toward an inner periphery side thereof. The outer peripheral wall 120b is brought into a pressed state on the squeegee roller 126 by such shifting, and the squeegee roller 126 rotates following the drum 120. Onto the outer peripheral surface of the squeegee roller 126, the ink 128 having passed through the gap between the squeegee roller 126 and the doctor roller 127 is adhered. The ink 128 thus adhered is sequentially supplied to an inner surface of the outer peripheral wall 120b by the rotation of the squeegee roller 126. Moreover, when the pressure roller 130 presses the outer peripheral wall 120b of the drum 120, the print sheet 111 conveyed between the drum 120 and the pressure roller 130 is conveyed while being brought into press contact with the stencil sheet 104 in between the squeegee roller 126 and the pressure roller 130. By press-contact force at this time, the ink 128 on the outer peripheral wall 120b side is transferred to the print sheet 111 side from the perforations of the stencil sheet 104, and an ink image is printed on the print sheet 111. Incidentally, in the stencil printing machines of the conventional inner press method and outer press method, ink pools are individually formed in the outer peripheral space of the inner press roller 106 and the doctor roller 109 and in the outer peripheral space of the squeegee roller 126 and the doctor roller 127, and the inks 103 and 128 in the ink pools are supplied to the screen 102 and outer peripheral wall 120b of the drums 100 and 120 at the time of printing. Hence, when the printing is not performed for a long time, the inks 103 and 128 having accumulated in the ink pools and the inks 103 and 128 adhered onto the drums 100 and 120 and the like will be left standing in a state of being in contact with the atmosphere, which has caused a problem of degradation of the inks 103 and 128. SUMMARY OF THE INVENTION In this connection, the applicant of the present invention has proposed a stencil printing machine, which includes: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies ink to the surface of the outer peripheral wall from the ink supply port; and a pressure roller which presses a print medium fed thereto to the outer peripheral wall. In this stencil printing machine, when the print medium is fed thereto in a state where the outer peripheral wall of the drum is rotated and the ink is supplied to the surface of the outer peripheral wall from the ink supply port, the print medium is conveyed while being pressed to the stencil sheet and the outer peripheral wall of the drum by the pressure roller. Meanwhile, the ink between the outer peripheral wall of the drum and the stencil sheet is diffused downstream in a printing direction while being squeezed. Moreover, the ink thus diffused oozes out of perforations of the stencil sheet to be transferred to the print medium side, and an ink image is printed on the print medium. Accordingly, the ink supplied to the drum is held in a substantially enclosed space between the outer peripheral wall of the drum and the stencil sheet, and is restricted from being brought into contact with the atmosphere as much as possible. Hence, degradation of the ink can be prevented as much as possible even if the printing is not performed for a long time. However, in the stencil printing machine described above, the ink supply port is open to the outer peripheral wall of the drum, and this ink supply port is not always completely protected from the contact with the atmosphere even in a state of being covered with the stencil sheet. Moreover, some ink accumulates and remains in the ink supply port even after supply of the ink is stopped. Accordingly, such possibilities cannot be denied that the ink is cured by the contact with the atmosphere to clog the ink supply port, that the ink is degraded, and so on. In this connection, it is an object of the present invention to provide a stencil printing machine capable of restricting ink clogging of the ink supply port and the degradation of the ink in a type including the ink supply port on the outer peripheral wall of the drum. In order to achieve the foregoing object, the present invention includes: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies ink to the surface of the outer peripheral wall from the ink supply port; a pressure roller which presses a print medium fed thereto to the outer peripheral wall; and a first cap device which shifts between a closing position of closing the ink supply port and an opening position of opening the ink supply port. According to the above-described configuration, when the drum is stopped, the ink supply port is closed by the first cap device, thus making it possible not to bring the ink in the ink supply port into contact with the atmosphere. Hence, ink clogging and degradation of the ink at the ink supply port can be restricted. A preferred embodiment of the present invention may be adapted to include: an ink return device which has an ink return port on the outer peripheral wall, and returns the ink which flows into the ink return port; and a second cap device which shifts between a closing position of closing the ink return port and an opening position of opening the ink return port. According to the above-described configuration, when the drum is stopped, the ink return port is closed by the second cap device, thus making it possible not to bring the ink in the ink return port into contact with the atmosphere. Hence, ink clogging and degradation of the ink at the ink return port can be restricted. The first cap device may be adapted to include: a drive source fixed to a machine body side; and a first cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. According to the above-described configuration, the first cap device can be installed without involving a design change of the drum. Hence, the first cap device can be easily installed in the existing stencil printing machine. The second cap device may be adapted to include: a drive source fixed to a machine body side; and a second cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. According to the above-described configuration, the second cap device can be installed without involving the design change of the drum. Hence, the second cap device can be easily installed in the existing stencil printing machine. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of principal portions for printing according to an inner press method of a conventional example. FIG. 2 is a schematic view of an ink supply device according to the inner press method of the conventional example. FIG. 3 is a schematic view of principal portions for printing according to an outer press method according to the conventional example. FIG. 4 shows an embodiment of the present invention, and is a schematic configuration view of a stencil printing machine. FIG. 5 shows the embodiment of the present invention, and is a perspective view of a drum. FIG. 6 shows the embodiment of the present invention, and is a cross-sectional view along a line 6-6 in FIG. 5. FIG. 7 shows the embodiment of the present invention, and is a cross-sectional view along a line 7-7 in FIG. 5. FIG. 8 shows the embodiment of the present invention, and is a partial cross-sectional view of the drum, showing a state where an ink supply port and an ink return port are closed by a first cap device and a second cap device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is described below based on the drawings. As shown in FIG. 4, a stencil printing machine is mainly composed of an original reading unit 1, a stencil making unit 2, a printing unit 3, a paper feed unit 4, a paper discharge unit 5, and a stencil disposal unit 6. The original reading unit 1 includes an original setting tray 10 on which an original to be printed is mounted, reflective-type original sensors 11 and 12 which detect the presence of the original on the original setting tray 10, original conveyer rollers 13 and 14 which convey the original on the original setting tray 10, a stepping motor 15 which rotationally drives the original conveyer rollers 13 and 14, a contact image sensor 16 which optically reads image data of the original conveyed by the original conveyer rollers 13 and 14 and converts the read data into electrical signals, and an original discharge tray 17 on which the original discharged from the original setting tray 10 is mounted. The original mounted on the original setting tray 10 is conveyed by the original conveyer rollers 13 and 14, and the image sensor 16 reads the image data of the conveyed original. The stencil making unit 2 includes a stencil housing 19 which houses a long and rolled stencil sheet 18, a thermal print head 20 placed downstream of the stencil housing 19 in a conveying direction, a platen roller 21 placed at a position opposite to the thermal print head 20, a pair of stencil transfer rollers 22 and 22 placed downstream of the platen roller 21 and the thermal print head 20 in the conveying direction, a write pulse motor 23 which rotationally drives the platen roller 21 and the stencil transfer rollers 22 and 22, and a stencil cutter 24 placed downstream of the pair of stencil transfer rollers 22 and 22 in the conveying direction. The long stencil sheet 18 is conveyed by the rotation of the platen roller 21 and the stencil transfer rollers 22 and 22. Based on the image data read by the image sensor 16, each of dot-shaped heating elements of the thermal print head 20 selectively performs a heating operation, and thus the stencil sheet 18 is perforated due to thermal sensitivity thereof to make a stencil. Then, the stencil sheet 18 thus made is cut by the stencil cutter 24 to make the stencil sheet 18 with a predetermined length. The printing unit 3 includes a drum 26 which rotates in a direction of an arrow A of FIG. 4 by driving force of a main motor 25, a stencil clamping portion 27 which is provided on an outer peripheral surface of the drum 26 and clamps a tip end of the stencil sheet 18, an ink supply device 54 which supplies an ink to the surface of the drum 26, and an ink return device 73 which returns extra ink on the surface of the drum 26. Moreover, the printing unit 3 includes a stencil confirming sensor 28 which detects whether or not the stencil sheet 18 is wound and attached around the outer peripheral surface of the drum 26, a reference position detecting sensor 30 which detects a reference position of the drum 26, and a rotary encoder 31 which detects rotation of the main motor 25. Based on a detection output of the reference position detecting sensor 30, a pulse outputted from the rotary encoder 31 is detected, thus enabling a rotation position of the drum 26 to be detected. Furthermore, the printing unit 3 includes a pressure roller 35 placed below the drum 26. The pressure roller 35 is constructed to be shiftable between a press position of pressing the outer peripheral wall of the drum 26 by driving force of a solenoid device 36 and a standby position of being spaced from the outer peripheral surface of the drum 26. The pressure roller 35 is always located at the press position during a period of a printing mode (including a trial print mode) and located at the standby position during a period other than the period of the printing mode. Then, the tip end of the stencil sheet 18 conveyed from the stencil making unit 2 is clamped by the stencil clamping portion 27, and the drum 26 is rotated in such a clamping state, so that the stencil sheet 18 is wound and attached around the outer peripheral surface of the drum 26. Then, print sheets (print media) 37, which are fed by the paper feed unit 4 in synchronization with the rotation of the drum 26, are pressed to the stencil sheet 18 wound around the drum 26 by the pressure roller 35. Thus, the ink is transferred from perforations of the stencil sheet 18 onto the print sheets 37, and an image is printed thereon. The paper feed unit 4 includes a paper feed tray 38 on which the print sheets 37 are stacked, first paper feed rollers 39 and 40 which convey only the uppermost print sheet 37, a pair of second paper feed rollers 41 and 41 which convey the print sheet 37, which has been conveyed by the first paper feed rollers 39 and 40, between the drum 26 and the pressure roller 35 in synchronization with the rotation of the drum 26, and a paper feed sensor 42 which detects whether or not the print sheet 37 has been conveyed between the pair of second paper feed rollers 41 and 41. The first paper feed rollers 39 and 40 are constructed such that the rotation of the main motor 25 is selectively transmitted thereto through a paper feed clutch 43. The paper discharge unit 5 includes a sheet separator claw 44 which separates the printed print sheets 37 from the drum 26, a conveying passage 45 through which the print sheets 37 separated from the drum 26 by the sheet separator claw 44 are conveyed, and a paper receiving tray 46 on which the print sheets 37 discharged from the conveying passage 45 are mounted. The stencil disposal unit 6 includes a disposed stencil conveying device 47, a stencil disposal box 48, and a disposed stencil compression member 49. The disposed stencil conveying device 47 guides the tip end of the stencil sheet 18, of which clamping has been released from the outer peripheral surface of the drum 26, and conveys the used stencil sheet 18 thus guided while peeling off the same stencil sheet 18 from the drum 26. The stencil disposal box 48 houses the stencil sheet 18 conveyed by the disposed stencil conveying device 47. The disposed stencil compression member 49 pushes the stencil sheet 18, which has been conveyed by the disposed stencil conveying device 47 into the stencil disposal box 48, into a bottom of the stencil disposal box 48. Next, configurations of the drum 26, the stencil clamping portion 27, the ink supply device 54 and the ink return device 73 are described. As shown in FIG. 5 to FIG. 7, the drum 26 includes a support shaft 50 fixed to a machine body H, a pair of side disks 52 and 52 supported on the support shaft 50 so as to be freely rotatable with bearings 51 interposed therebetween, respectively, and a cylindrical outer peripheral wall 53 fixed between the pair of side disks 52 and 52. The outer peripheral wall 53 is rotationally driven by rotation force of the main motor 25 integrally with the pair of side disks 52 and 52. Moreover, the outer peripheral wall 53 has rigidity, and is formed of an ink impermeable member which does not allow the ink to permeate therethrough. Furthermore, the outer peripheral surface of the outer peripheral wall 53 is processed with a fluorine-contained resin coating process such as a Teflon (registered trademark) coating process, and is formed into an even cylindrical surface. The stencil clamping portion 27 is provided by use of a concave clamping portion 53a formed on the outer peripheral wall 53 along an axial direction of the support shaft 50. One end of the stencil clamping portion 27 is supported on the outer peripheral wall 53 such that the stencil clamping portion 27 is freely rotatable. The stencil clamping portion 27 is provided so as not to protrude from the outer peripheral wall 53 in a clamping state shown by a solid line in FIG. 7 while the stencil clamping portion 27 protrudes from the outer peripheral wall 53 in a clamping release state shown by a virtual line in FIG. 7. Hence, the stencil clamping portion 27 is configured to be capable of clamping the stencil sheet 18 without protruding from the outer peripheral wall 53. The outer peripheral wall 53 is rotated in the direction of the arrow A of FIG. 5 and FIG. 7, and a position thereof rotated a little from the stencil clamping portion 27 is set at a printing start point. Hence, the rotation direction A becomes a printing direction M, and an area that follows the printing start point is set as a printing area. In this first embodiment, the maximum printing area is set at a region sufficient for printing an A3-size sheet. Moreover, an ink supply port 55 of the ink supply device 54 is provided, for example, upstream of the maximum printing area of the outer peripheral wall 53 in the printing direction M. As shown in FIG. 5 to FIG. 7, the ink supply device 54 includes an ink container 57 in which the ink is stored, an ink pump 58 which suctions the ink in the ink container 57, a first pipe 59 which supplies the ink suctioned by the ink pump 58, the support shaft 50 to which the other end of the first pipe 59 is connected and in which an ink passage 60 is formed and a hole 61 is formed at a position 180 degrees opposite thereto, a rotary joint 63 which is supported on an outer periphery of the support shaft 50 so as to be freely rotatable and in which a through hole 62 that is able to communicate with the hole 61 is formed, a second pipe 64 in which one end thereof is connected to the rotary joint 63 and the other end thereof is guided to the outer peripheral wall 53, and the ink supply port 55 to which the other end of the second pipe 64 is connected and which is open to the surface of the outer peripheral wall 53. The ink supply port 55 is formed by use of an ink supplying concave portion formed along a direction N perpendicular to the printing direction of the outer peripheral wall 53, and of an ink distribution member 68 formed inside the ink supplying concave portion. The ink supply port 55 is formed to be closable by a first cap device 90. As shown in FIG. 7 and FIG. 8, the first cap device 90 is composed of a solenoid unit 91 which is a drive source fixed to the machine body H side, and a first cap 92 which shifts between a closing position (position of FIG. 8) of being brought into intimate contact with the surface of the outer peripheral wall 53 by drive of the solenoid unit 91 and an opening position (position of FIG. 7) of being spaced from the surface of the outer peripheral wall 53 toward the above thereby. The first cap 92 is formed of a rubber material good in contact characteristics, and is set at a position opposite to the ink supply port 55 with respect to the outer peripheral wall 53 located at a standby position (position of FIG. 7 and FIG. 8) for the rotation. As shown in FIG. 5 to FIG. 7, the ink return device 73 is composed of an ink return port 72 open at a printing position, for example, downstream of the maximum printing area of the outer peripheral wall 53, a third pipe 74 in which one end is connected to the ink return port 72, the rotary joint 63 to which the other end of the third pipe 74 is connected and in which a communication hole 75 is formed, the support shaft 50, a fourth pipe 77 in which one end is connected to the support shaft 50, a filter 80 which is interposed midway through the fourth pipe 77 and traps paper powder and the like, an ink pump (for example, trochoid pump) 78 which is interposed midway through the fourth pipe 77 and suctions the ink in the fourth pipe 77, and a return container 79 to which the other end of the fourth pipe 77 is connected. Here, regarding the support shaft 50, the rotary joint 63 is supported thereon so as to be freely rotatable, a hole 76a to which the communication hole 75 is connectable is formed therein, and an ink passage 76b is formed in the inside thereof. The ink return port 72 is formed by use of an ink returning concave portion formed along the perpendicular-to-printing direction N of the outer peripheral wall 53, and a pipe fixing member 82 placed in the inside thereof. The ink return port 72 is formed to be closable by a second cap device 93. As shown in FIG. 7 and FIG. 8, the second cap device 93 is composed of a solenoid unit 94 which is a drive source fixed to the machine body H side, and a second cap 95 which shifts between a closing position (position of FIG. 8) of being brought into intimate contact with the surface of the outer peripheral wall 53 by drive of the solenoid unit 94 and an opening position (position of FIG. 7) of being spaced from the surface of the outer peripheral wall 53 toward the above thereby. The second cap 95 is formed of a rubber material good in contact characteristics, and is set at a position opposite to the ink return port 72 with respect to the outer peripheral wall 53 located at the standby position (position of FIG. 7 and FIG. 8) for the rotation. The rotary joint 63 is made to also function as one for the ink supply device 54. Moreover, the support shaft 50 is also used as one for an ink passage of the ink supply device 54, and accordingly, adopts a structure of a double pipe. Next, operations of the stencil printing machine are briefly described. It is assumed that the used stencil sheet 18 is removed from the outer peripheral wall 53 of the drum 26, and that the first cap 92 of the first cap device 90 and the second cap 95 of the second cap device 93 are located at the opening positions of FIG. 7. First, when a stencil making mode is selected, in the stencil making unit 2, the stencil sheet 18 is conveyed by the rotation of the platen roller 21 and the stencil transfer rollers 22 and 22. Based on the image data read by the original reading unit 1, a large number of heating elements of the thermal print head 20 selectively perform the heating operation, and thus the stencil sheet 18 is perforated due to the thermal sensitivity thereof to make the stencil. Then, the stencil sheet 18 thus made is cut at the predetermined spot by the stencil cutter 24. Thus, the stencil sheet 18 with the predetermined length is made. In the printing unit 3, the tip end of the stencil sheet 18 made in the stencil making unit 2 is clamped by the stencil clamping portion 27 of the drum 26, and the drum 26 is rotated in such a clamping state, so that the stencil sheet 18 is wound, attached and loaded around the outer peripheral surface 53 of the drum 26. Next, when the printing mode is selected, in the printing unit 3, the drum 26 is rotationally driven, and the ink supply device 54 and the ink return device 73 start driving. Then, the ink is supplied from the ink supply port 55 to the outer peripheral wall 53, and the ink thus supplied is held between the outer peripheral wall 53 and the stencil sheet 18, and the pressure roller 35 is shifted from the standby position to the press position. The paper feed unit 4 feeds the print sheets 37 between the drum 26 and the pressure roller 35 in synchronization with the rotation of the drum 26. The print sheets 37 thus fed are pressed to the outer peripheral wall 53 of the drum 26 by the pressure roller 35, and conveyed by the rotation of the outer peripheral wall 53 of the drum 26. Specifically, the print sheets 37 are conveyed while being brought into intimate contact with the stencil sheet 18. Moreover, at the same time when the printed sheets 37 are conveyed, the ink held between the outer peripheral wall 53 of the drum 26 and the stencil sheet 18 is diffused downstream in the printing direction M while being squeezed by the pressing force of the pressure roller 35. The ink thus diffused oozes out of the perforations of the stencil sheet 18, and is transferred to the printed sheets 37. In the manner described above, the ink image is printed on the print sheets 37 in the process where the print sheets 37 pass between the outer peripheral wall 53 of the drum 26 and the pressure roller 35. With regard to the print sheets 37 which have come out from between the outer peripheral wall 53 of the drum 26 and the pressure roller 35, the tip ends thereof are peeled off from the drum 26 by the sheet separator claw 44. The print sheets 37 separated from the drum 26 are discharged through the conveying passage 45 to the paper receiving tray 46, and are stacked there. During the printing operations, extra ink which has flown downstream of the maximum printing area of the outer peripheral wall 53 flows into the ink return port 72 of the ink return device 73 and is returned there, and accordingly, ink leakage from the outer peripheral wall 53 is prevented. When printing of the set number of print sheets is completed, the rotation of the drum 26 is stopped, the drum 26 is located at the standby position for the rotation, and the drive of the ink supply device 54 is stopped. Thus, the supply of the ink to the outer peripheral wall 53 is stopped. The drive of the ink return device 73 is stopped a little later than the stop of the ink supply device 54, and the extra ink which has remained on the outer peripheral wall 53 is returned through the ink return port 72. Moreover, the pressure roller 35 is returned back to the standby position from the press position. Furthermore, the solenoid units 91 and 94 of the first cap device 90 and the second cap device 93 drive to shift the first cap 92 and the second cap 95 to the respective closing positions (positions of FIG. 8), and both of the ink supply port 55 and the ink return port 72 are closed by the first cap 92 and the second cap 95. After the operations described above are completed, the stencil printing machine enters a standby mode. During the standby mode, when making of a new stencil sheet is started and so on and a stencil disposal mode is thus selected, the solenoid units 91 and 94 of the first cap device 90 and the second cap device 93 drive to shift the first cap 92 and the second cap 95 to the respective opening positions (positions of FIG. 7), and both of the ink supply port 55 and the ink return port 72 are opened. Next, the stencil clamping portion 27 of the drum 26 is shifted to a clamping release position, and the tip end of the stencil sheet 18, of which clamping has been released, is guided to the disposed stencil conveying device 47, following the rotation of the drum 26, and housed in the stencil disposal box 48. During the standby mode, when the printing mode is selected again, the solenoid units 91 and 94 of the first cap device 90 and the second cap device 93 drive to shift the first cap 92 and the second cap 95 to the respective opening positions (positions of FIG. 7), and both of the ink supply port 55 and the ink return port 72 are opened. Then, the stencil printing machine enters the printing operations described above. As above, in this stencil printing machine, when the drum 26 is driven, the first cap device 90 and the second cap device 93 are located at the opening positions to enable the drum 26 to be driven, and the ink supply from the ink supply port 55 and the ink return from the ink return port 72 are made possible, thus making it possible to perform the printing operations and the like. Meanwhile, when the drum 26 is stopped, the first cap device 90 and the second cap device 93 are located at the closing positions to close the ink supply port 55 and the ink return port 72, thus making it possible not to bring the ink in the ink supply port 55 and the ink return port 72 into contact with the atmosphere. Hence, ink clogging and degradation of the ink at the ink supply port 55 and the ink return port 72 can be restricted. Moreover, the ink is always served for the printing in such a best condition of being hardly deteriorated, and accordingly, a degree of freedom in selecting the ink is increased very much. Note that, though the first cap 92 and the second cap 95 close the ink supply port 55 and the ink return port 72 from above the stencil sheet 18, the stencil sheet 18 may be removed from the outer peripheral wall 53, and the first cap 92 and the second cap 95 may directly close the ink supply port 55 and the ink return port 72. When the stencil printing machine is not used for a long period, it is more effective to close the ink supply port 55 and the ink return port 72 directly by the first cap 92 and the second cap 95 for preventing the ink clogging and the degradation of the ink. In the above-described embodiment, the first cap device 90 is composed of the solenoid unit 91 fixed to the machine body H side, and the first cap 92 which shifts between the closing position of being brought into intimate contact with the surface of the outer peripheral wall 53 by the drive of the solenoid unit 91 and the opening position of being spaced from the surface of the outer peripheral wall 53 toward the above thereby. Therefore, the first cap device 90 can be installed without involving a design change of the drum 26. Hence, the first cap device 90 can be easily attached onto the existing stencil printing machine. In the above-described embodiment, the second cap device 93 is composed of the solenoid unit 94 fixed to the machine body H side, and the second cap 95 which shifts between the closing position of being brought into intimate contact with the surface of the outer peripheral wall 53 by the drive of the solenoid unit 94 and the opening position of being spaced from the surface of the outer peripheral wall 53 toward the above thereby. Therefore, the second cap device 93 can be installed without involving a design change of the drum 26. Hence, the second cap device 93 can be easily attached onto the existing stencil printing machine. In the above-described embodiment, though the first cap device 90 and the second cap device 93 have the solenoid units 91 and 94, respectively, the first cap device 90 and the second cap device 93 may be configured to be shifted by a single solenoid unit because it is satisfactory if the first cap 92 and the second cap 95 are shifted at the same timing between the closing positions and the opening positions. Such a configuration achieves more reduction of parts count and cost. Moreover, the drive source may be composed of other one than the solenoid device, for example, a motor. Moreover, in the above-described embodiment, though the first cap device 90 capable of closing the ink supply port 55 and the second cap device 93 capable of closing the ink return port 72 are provided, only the first cap device 90 may be provided. In the drum 26 in which the ink return port 72 is not provided on the outer peripheral wall 53, naturally, only the first cap device 90 is installed. Moreover, in the above-described embodiment, though the ink return port 72 is provided at the printing position downstream of the maximum printing area of the outer peripheral wall 53, ink return grooves which communicate with the ink return port 72 may be provided on both-side positions of the maximum printing area of the outer peripheral wall 53. When the ink return grooves are provided on both sides in such a way, the ink leakage not only from the end of the outer peripheral wall 53 but also from both sides can be surely prevented. Furthermore, an ink return groove which communicates with the both-side ink return grooves may be provided at a position upstream of the maximum printing area of the outer peripheral wall 53 (position upstream of the ink supply port 55). When the ink return groove is provided on the top in such a way, ink leakage from the top can also be surely prevented. Note that, in the above-described embodiment, though the first and second cap devices 90 and 93 are composed of the solenoid units 91 and 94 fixed to the machine body H side, and the first and second caps 92 and 95 which are provided integrally with the respective solenoid devices 91 and 94 and intimately contact and are spaced from the outer peripheral wall 53 of the drum 26, the respective solenoid devices may be provided on the machine body side, and the respective caps may be provided on the drum side. When such a mode is applied to a stencil printing machine in which a drum is set freely detachable from a machine body, the drum is capped with the respective caps even when the drum is detached therefrom, and accordingly, this mode is effective for preventing the degradation of the ink, and so on. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a stencil printing machine which conveys a print medium while pressing the print medium to a drum on which a stencil sheet is mounted, and transfers ink oozing from perforations of the stencil sheet onto the print medium. 2. Description of the Related Art As a conventional printing method of a stencil printing machine, there are an inner press method (refer to Japanese Patent Laid-Open Publication No. Hei 7-132675 (published in 1995)) and an outer press method (refer to Japanese Patent Laid-Open Publication No. 2001-246828). The inner press method is briefly described. As shown in FIG. 1 , a drum 100 and a back press roller 101 are provided, and the drum 100 and the back press roller 101 are provided so as to be freely rotatable in a state where outer peripheral surfaces thereof are partially made substantially adjacent to each other. A stencil clamping portion 100 a which clamps a tip end of a stencil sheet 104 is provided on the outer peripheral surface of the drum 100 , and an outer peripheral wall other than the stencil clamping portion 100 a is formed of a screen 102 which is flexible and ink permeable. An ink supply mechanism 105 is provided inside the drum 100 . As shown in FIG. 2 , this ink supply mechanism 105 includes an inner press roller 106 which is an ink supply roller, and the inner press roller 106 is provided on a roller support member 107 so as to be freely rotatable. The inner press roller 106 is configured to be shiftable between a press position where the roller support member 107 is energized in a direction of an arrow a of FIG. 2 to press an inner peripheral surface of the screen 102 and a standby position where the roller support member 107 is rotated in a direction of an arrow b of FIG. 2 to be spaced from the inner peripheral surface of the screen 102 . The inner press roller 106 is set at the press position when a print sheet 111 passes therethrough, and otherwise, set at the standby position. Moreover, the inner press roller 106 has a function to apply printing pressure from an inner periphery side of the screen 102 . The roller support member 107 is supported so as to be freely rotatable about a support shaft 108 , and a doctor roller 109 and a drive rod 110 are individually provided on the roller support member 107 . The doctor roller 109 has a cylindrical shape, and is fixed to the roller support member 107 at a position close to the inner press roller 106 . The drive rod 110 is supported on the roller support member 107 so as to be freely rotatable, and is placed in an upper space composed of outer peripheral surfaces of the inner press roller 106 and the doctor roller 109 on sides thereof adjacent to each other. Ink 103 is supplied from an ink supply unit (not shown) to the upper space. Next, printing operations are schematically described in order. The stencil sheet 104 on which a perforated image is formed is attached onto an outer peripheral surface of the screen 102 . Then, during a printing mode, the drum 100 and the back press roller 101 are rotated in synchronization with each other in directions shown in arrows in FIG. 1 , and the print sheet 111 is conveyed between the drum 100 and the back press roller 101 . When the print sheet 111 is fed, the inner press roller 106 presses the screen 102 , and the inner press roller 106 rotates following the drum 100 in such a pressing state. The ink 103 having passed through a gap between the inner press roller 106 and the doctor roller 109 is adhered onto the outer peripheral surface of the inner press roller 106 , and the ink 103 thus adhered is sequentially supplied to an inner surface of the screen 102 by the rotation of the inner press roller 106 . Moreover, when the inner press roller 106 presses the screen 102 , the screen 102 swells out to the outer periphery side thereof by pressing force at this time, and the screen 102 is put into a press-contact state with the back press roller 101 . Then, the print sheet 111 conveyed between the drum 100 and the back press roller 101 is conveyed while being brought into press contact with the screen 102 and the stencil sheet 104 in between the inner press roller 106 and the back press roller 101 . By press-contact force at this time, the ink 103 on the screen 102 side is transferred to the print sheet 111 from perforations of the stencil sheet 104 , and an ink image is printed on the print sheet 111 . The outer press method is briefly described. As shown in FIG. 3 , a drum 120 is provided. A stencil clamping portion 120 a which clamps the tip end of the stencil sheet 104 is provided on an outer peripheral surface of this drum 120 , and an outer peripheral wall 120 b other than the stencil clamping portion 120 a is formed of an ink permeable member with a porous structure. An ink supply mechanism 125 is provided inside the drum 120 . The ink supply mechanism 125 includes a squeegee roller 126 supported so as to be freely rotatable, and a doctor roller 127 placed adjacent to the squeegee roller 126 . Ink 128 accumulates in an outer peripheral space surrounded by the squeegee roller 126 and the doctor roller 127 . The ink 128 adhered onto the outer periphery of the rotating squeegee roller 126 passes through a gap between the squeegee roller 126 and the doctor roller 127 , and thus only the ink 128 with a predetermined film thickness is adhered onto the squeegee roller 126 , and the ink 128 with the predetermined film thickness is supplied to an inner surface of the outer peripheral wall 120 b. Moreover, a pressure roller 130 is provided at a position opposite to the squeegee roller 126 , which is also an outside position of the drum 120 . The pressure roller 130 is configured to be shiftable between a press position of pressing the outer peripheral wall 120 b of the drum 120 and a standby position of being spaced from the outer peripheral wall 120 b of the drum 120 . The squeegee roller 126 is fixed to a support member which supports the outer peripheral wall 120 b of the drum 120 so as to be freely rotatable, and an outer peripheral surface of the squeegee roller 126 and the inner peripheral surface of the outer peripheral wall 120 b of the drum 120 are brought into a state of being slightly spaced from one another in a state where the outer peripheral wall 120 b of the drum 120 is not pressed by the pressure roller 130 . When the outer peripheral wall 120 b of the drum 120 is pressed by the pressure roller 130 , the outer peripheral wall 120 b of the drum 120 is bent, and thus the outer peripheral surface of the squeegee roller 126 and the inner peripheral surface of the outer peripheral wall 120 b of the drum 120 are brought into contact with each other. Next, printing operations are schematically described in order. The stencil sheet 104 on which the perforated image is formed is attached onto an outer peripheral surface of the outer peripheral wall 120 b of the drum 120 . Then, during the printing mode, the outer peripheral wall 120 b of the drum 120 is rotated in a direction shown by an arrow in FIG. 3 , and the print sheet 111 is fed between the drum 120 and the pressure roller 130 . When the print sheet 111 is fed, the pressure roller 130 presses the outer peripheral wall 120 b of the drum 120 , and the outer peripheral wall 120 b is shifted toward an inner periphery side thereof. The outer peripheral wall 120 b is brought into a pressed state on the squeegee roller 126 by such shifting, and the squeegee roller 126 rotates following the drum 120 . Onto the outer peripheral surface of the squeegee roller 126 , the ink 128 having passed through the gap between the squeegee roller 126 and the doctor roller 127 is adhered. The ink 128 thus adhered is sequentially supplied to an inner surface of the outer peripheral wall 120 b by the rotation of the squeegee roller 126 . Moreover, when the pressure roller 130 presses the outer peripheral wall 120 b of the drum 120 , the print sheet 111 conveyed between the drum 120 and the pressure roller 130 is conveyed while being brought into press contact with the stencil sheet 104 in between the squeegee roller 126 and the pressure roller 130 . By press-contact force at this time, the ink 128 on the outer peripheral wall 120 b side is transferred to the print sheet 111 side from the perforations of the stencil sheet 104 , and an ink image is printed on the print sheet 111 . Incidentally, in the stencil printing machines of the conventional inner press method and outer press method, ink pools are individually formed in the outer peripheral space of the inner press roller 106 and the doctor roller 109 and in the outer peripheral space of the squeegee roller 126 and the doctor roller 127 , and the inks 103 and 128 in the ink pools are supplied to the screen 102 and outer peripheral wall 120 b of the drums 100 and 120 at the time of printing. Hence, when the printing is not performed for a long time, the inks 103 and 128 having accumulated in the ink pools and the inks 103 and 128 adhered onto the drums 100 and 120 and the like will be left standing in a state of being in contact with the atmosphere, which has caused a problem of degradation of the inks 103 and 128 . | <SOH> SUMMARY OF THE INVENTION <EOH>In this connection, the applicant of the present invention has proposed a stencil printing machine, which includes: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies ink to the surface of the outer peripheral wall from the ink supply port; and a pressure roller which presses a print medium fed thereto to the outer peripheral wall. In this stencil printing machine, when the print medium is fed thereto in a state where the outer peripheral wall of the drum is rotated and the ink is supplied to the surface of the outer peripheral wall from the ink supply port, the print medium is conveyed while being pressed to the stencil sheet and the outer peripheral wall of the drum by the pressure roller. Meanwhile, the ink between the outer peripheral wall of the drum and the stencil sheet is diffused downstream in a printing direction while being squeezed. Moreover, the ink thus diffused oozes out of perforations of the stencil sheet to be transferred to the print medium side, and an ink image is printed on the print medium. Accordingly, the ink supplied to the drum is held in a substantially enclosed space between the outer peripheral wall of the drum and the stencil sheet, and is restricted from being brought into contact with the atmosphere as much as possible. Hence, degradation of the ink can be prevented as much as possible even if the printing is not performed for a long time. However, in the stencil printing machine described above, the ink supply port is open to the outer peripheral wall of the drum, and this ink supply port is not always completely protected from the contact with the atmosphere even in a state of being covered with the stencil sheet. Moreover, some ink accumulates and remains in the ink supply port even after supply of the ink is stopped. Accordingly, such possibilities cannot be denied that the ink is cured by the contact with the atmosphere to clog the ink supply port, that the ink is degraded, and so on. In this connection, it is an object of the present invention to provide a stencil printing machine capable of restricting ink clogging of the ink supply port and the degradation of the ink in a type including the ink supply port on the outer peripheral wall of the drum. In order to achieve the foregoing object, the present invention includes: a drum which is freely rotatable and has an outer peripheral wall formed of an ink impermeable member, in which a stencil sheet is mounted on a surface of the outer peripheral wall; an ink supply device which has an ink supply port on the outer peripheral wall of the drum, and supplies ink to the surface of the outer peripheral wall from the ink supply port; a pressure roller which presses a print medium fed thereto to the outer peripheral wall; and a first cap device which shifts between a closing position of closing the ink supply port and an opening position of opening the ink supply port. According to the above-described configuration, when the drum is stopped, the ink supply port is closed by the first cap device, thus making it possible not to bring the ink in the ink supply port into contact with the atmosphere. Hence, ink clogging and degradation of the ink at the ink supply port can be restricted. A preferred embodiment of the present invention may be adapted to include: an ink return device which has an ink return port on the outer peripheral wall, and returns the ink which flows into the ink return port; and a second cap device which shifts between a closing position of closing the ink return port and an opening position of opening the ink return port. According to the above-described configuration, when the drum is stopped, the ink return port is closed by the second cap device, thus making it possible not to bring the ink in the ink return port into contact with the atmosphere. Hence, ink clogging and degradation of the ink at the ink return port can be restricted. The first cap device may be adapted to include: a drive source fixed to a machine body side; and a first cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. According to the above-described configuration, the first cap device can be installed without involving a design change of the drum. Hence, the first cap device can be easily installed in the existing stencil printing machine. The second cap device may be adapted to include: a drive source fixed to a machine body side; and a second cap which shifts between a closing position of being brought into intimate contact with the surface of the outer peripheral wall by drive of the drive source and an opening position of being spaced from the surface of the outer peripheral wall toward above thereby. According to the above-described configuration, the second cap device can be installed without involving the design change of the drum. Hence, the second cap device can be easily installed in the existing stencil printing machine. | 20050124 | 20060509 | 20050728 | 74554.0 | 0 | EVANISKO, LESLIE J | STENCIL PRINTING MACHINE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,039,886 | ACCEPTED | Distributed contact information management | A method and system for interaction with webservices and for performing distributed contact management use standard interfaces to communicate with other entities in an identity management network. The use of homesites as user data stores allows for homesite to homesite communication to allow for distributed contact management, and the generic interface allows for homesite to webservice interaction. | 1. A method of obtaining contact information from a node in an identity management network, the method comprising: receiving a homesite identifier and a user identifier associated with an email address; requesting from a homesite associated with the received homesite identifier contact information for a user associated with the received user identifier; and receiving from the homesite associated with the received homesite identifier the requested contact information. 2. The method of claim 1 further including the step of forwarding the received contact information to a user. 3. The method of claim 1 wherein the step of receiving a homesite identifier includes receiving the homesite identifier and user identifier from a network root. 4. The method of claim 3 wherein the step of receiving a homesite identifier is preceded by the step of transmitting a request for a user identifier and a homesite identifier associated with an email address. 5. The method of claim 1 wherein the user identifier is a globally unique persona identifier. 6. The method of claim 1 wherein the step of receiving the requested contact information is preceded by obtaining approval for the release of the contact information from the user associated with the requested contact information. 7. The method of claim 1 wherein the step of receiving the requested contact information includes receiving a universal resource indicator for receiving updated contact information. 8. A method of authorizing a webservice provider to release information, associated with a user, to a third party, the method comprising: receiving from the webservice provider a request for user authentication and authorization to release information to the third party; authenticating the user and obtaining user authorization for the release of the information; and forwarding to the webservice provider authorization from the authenticated user to release the information to the third party. 9. The method of claim 8 wherein the received request from the webservice provider is received via the third party. 10. The method of claim 8 wherein the received request includes an explanation of the information to be released to the third party. 11. The method of claim 10 wherein the explanation is a text explanation to be shown to the user prior to obtaining user authorization. 12. The method of claim 10 wherein the explanation is a programmatic explanation. 13. The method of claim 8 wherein the received request includes a nonce. 14. The method of claim 13 wherein the step of forwarding includes forwarding the nonce along with the response. 15. The method of claim 8 wherein the step of forwarding includes signing the response. 16. The method of claim 8 wherein the step of forwarding includes appending proof of authoritativeness for the user. 17. The method of claim 8 wherein the step of forwarding includes forwarding the authorization to the webservice provide via the third party. | CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 60/579,890, filed Jun. 16, 2004 and U.S. Provisional Application No. 60/605,150, filed Aug. 30, 2004, which are both incorporated herein by reference. FIELD OF THE INVENTION The present invention relates generally to electronic identity management systems. More particularly, the present invention relates to authentication and security for data exchange in a distributed hierarchical identity management system. BACKGROUND OF THE INVENTION In the field of identity management, there are a number of known systems for providing user identity services on the Internet. Microsoft's Passport™, and the Liberty Alliance identity management system are two such known examples, as are the identity management systems taught in Canadian Patent No. 2,431,311, and Canadian Patent Application Nos. 2,458,257, 2,468,351, and 2,468,585. Many known identity management systems offer secure logins, allowing a user to visit a site in the network (membersite) and obtain a secure login to that site using an identity store to authenticate the user identity over a secure channel. The use of a secure channel allows an identity store to provide the membersite with user login information and/or confidential user information. However, the reliance on secure channels increases the barrier to entry for membersites. Under a secure setup, lightweight, or simple, login is encumbered by the overhead of a secure channel. In an identity management system that relies upon homesites to act as an identity store which stores user identity information, it may be advantageous to provide a form of graduated security to allow a membersite to obtain identity information, including authentication, using a number of different channels, each with different security features. There is a further need for a mechanism through which a webservice provider can obtain user authentication and authorization for a third party to receive information. At present, if a third party wishes to aggregate information from a number of webservice providers for the user, or if a third party requires information from a webservice provider to further process before providing the results to a user, the third party and the webservice must be heavily linked. Typically, the third party must become associated with the webservice, and have its services bundled by the webservice provider. Thus a financial institution can use an aggregation service to perform analysis on a client's holdings, but a client cannot easily obtain an aggregation across a number of financial institutions. There is therefore a need for a mechanism for third parties to provide authentication of a user authorization for release of information provided by a webservice. There are at present a number of contact management services that allow a user to provide a list of known contacts. If the contacts provided a user subscribe to the same service, when one of the users updates a segment of a profile, the change is automatically reflected in the other users contact list. However, at present, these services are highly centralized. There is no automated mechanism to obtain information about users that have not subscribed. There is a plurality of these services, and at present there is no convenient mechanism for data exchange between them. This results in users forming small collective islands of contact sharing. There is a need for a distributed contact management system that allows users to share information with people in a vast identity management system that allows for automated updating of contact information. It is, therefore, desirable to provide an identity management system that can provide at least one of improved gradations in the security levels, support for third party webservices and support for distributed contact management. SUMMARY OF THE INVENTION It is an object of the present invention to obviate or mitigate at least one disadvantage of previous identity management systems. In a first aspect of the present invention, there is provided a method of obtaining contact information from a node in an identity management network. The method comprises receiving a homesite identifier and a user identifier associated with an email address; requesting from a homesite associated with the received homesite identifier contact information for a user associated with the received user identifier; and receiving from the homesite associated with the received homesite identifier the requested contact information. In an embodiment of the first aspect of the present invention, the method further includes the step of forwarding the received contact information to a user. In another embodiment, the step of receiving a homesite identifier includes receiving the homesite identifier and user identifier from a network root and is optionally preceded by the step of transmitting a request for a user identifier and a homesite identifier associated with an email address. In these embodiments, the user identifier can be a globally unique persona identifier. In another embodiment, the step of receiving the requested contact information is preceded by obtaining approval for the release of the contact information from the user associated with the requested contact information. In another embodiment, the step of receiving the requested contact information includes receiving a universal resource indicator for receiving updated contact information. In a second aspect of the present invention, there is provided a method of authorizing a webservice provider to release information, associated with a user, to a third party. The method comprises the steps of receiving from the webservice provider a request for user authentication and authorization to release information to the third party; authenticating the user and obtaining user authorization for the release of the information; and forwarding to the webservice provider authorization from the authenticated user to release the information to the third party. In an embodiment of the present invention, the received request from the webservice provider is received via the third party. In another embodiment, the received request includes an explanation of the information to be released to the third party, the explanation preferably includes a text explanation to be shown to the user prior to obtaining user authorization and a programmatic explanation. In another embodiment, the received request includes a nonce and the step of forwarding includes forwarding the nonce along with the response. In another embodiment, the step of forwarding includes signing the response, appending proof of authoritativeness for the user and forwarding the authorization to the webservice provide via the third party. Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein: FIG. 1 is a flowchart illustrating a method of the present invention; FIG. 2 is a flowchart illustrating a method of the present invention; FIG. 3 is a block diagram illustrating a lightweight login in a system of the present invention; FIG. 4 is a block diagram illustrating an increased security login in a system of the present invention; FIG. 5 is a block diagram illustrating a further increased security login in a system of the present invention; FIG. 6 is a block diagram illustrating a secure login in a system of the present invention; FIG. 7 is a flowchart illustrating a method of the present invention; FIG. 8 is a flowchart illustrating a method of the present invention; FIG. 9 is a block diagram illustrating the dataflow for providing authorization and authentication to a webservice provider; FIG. 10 is a block diagram illustrating an additional dataflow for authorization of a webservice provider; FIG. 11 is a block diagram illustrating a rich client interfacing with a homesite and a webservice provider; FIG. 12 is a block diagram illustrating a distributed contact management system of the present invention; FIG. 13 is a block diagram illustrating an automated user information distribution system of the present invention; and FIG. 14 is a block diagram illustrating a further embodiment of the automated user information distribution system illustrated in FIG. 13. DETAILED DESCRIPTION Generally, the present invention provides a method and system for identity management supporting graduated security levels, third party web services and contact management. In the following discussion, a hierarchical distributed identity management system is assumed, though one skilled in the art will appreciate that a number of these techniques can be utilized in other identity management networks or other environments where transactional security is of importance. In view of the need for a graduated security mechanism, the system of the present invention can provide a series of different levels of security. As noted with regard to the prior art, a mechanism for providing a series of graduated security levels provides membersites with the ability to determine the degree of security that they require. For sites that relied upon identification by the presence of a cookie, as many news based website do, or sites that relied upon simple username password combinations transmitted in cleartext prior to joining the identity management network, there is little need for requiring a very secure user identification channel. For such sites, requiring a secure login with signature verification for exchanged data serves as a barrier for entry. On the other side of the equation, financial service websites or websites providing medical histories are best served by very secure logins, with a mechanism that reduces the ability of malicious parties to perform man-in-the-middle type attacks. To provide such a varied login, the system of the present invention allows for a graduated security login. The graduated security login can use both differentiated levels of user authentication and differentiated levels of channel security. In prior art identity management systems, users are authenticated by providing a user identifier, such as a username, and a shared secret, such as a password. In other systems, typically reserved for specialty uses, other information was used in place of a shared secret, including fingerprint or biometric data. If the provided information was sufficiently unique, as it is with fingerprint and biometric data, the provision of this information was sufficient, and a user identifier was not required. Thus, depending on the level of security required for the authentication, different information has been required. However, in the prior art, login information has been globally set, so that regardless of what a user may want to do the same authentication test was applied. In the context of a membersite requesting user authentication, this is particularly cumbersome. A user, who is being authenticated by a news site so that a particular presentation layout can be selected based on user preference, does not need to be bothered with a request to authenticate using a user name and password, especially if the user has been recently authenticated. Additionally, the news site does not necessarily want the user to be authenticated by a username and password combination, or an even stronger authentication mechanism, as it makes the process too cumbersome for the user and diminishes the likelihood that the user will visit the site. Conversely, a financial institution may want the user to be authenticated by a homesite regardless of when the user was last authenticated, and may demand that that authentication. Similarly, a medical database may want to force the user to authenticate with the homesite and use a particularly robust authentication mechanism, such as a biometric scan, so that there is confidence that the user has been properly authenticated. To service the varied needs of different membersites, the homesite can support a series of different authentication levels. By supporting the plurality of different authentication mechanisms, the homesite can receive requests from a membersite to authenticate at a certain level of security. Additionally, a user can set a preference that when certain information, such as a credit card number, is requested, the homesite will only release it if authentication at a predefined level has been obtained. Thus, when a homesite receives a request for user information or user authentication, it can determine from both the request, and the requested information, the level of user authentication that is required. If the request for authentication and the requested information specify different levels of security, the homesite can use the higher of the two for the maximum security. One skilled in the art will appreciate that different dimensions of security can be applied independently of each other. Differing levels of user authentication security can be applied, so that users can be required to provide different complexities of authentication information, as can differing levels of security in the communication channel formed between the membersite and homesite through the user's browser. As a further dimension to the security level, a time sensitivity factor can be required of the user authentication, so that differing levels of user authentication security can be combined with a staleness factor that allows authentication of a user within a fixed period of time to be varied. FIG. 1 illustrates an exemplary embodiment of a method for executing the above-described graduated authentication system. In step 100 a homesite receives a user identity request from a membersite. A user identity request typically includes a request for one or both of user authentication and information about the user. In step 100 the homesite determines a required security level in accordance with the request. This determination can take the form of examining the request to determine a membersite's explicit request for a security level, examining user preferences which indicate that a user wishes to authenticate with nothing less than a specified authentication security level, examining a user specified minimum authentication security level associated with requested identity information, and optionally a set of homesite policies regarding the authentication of users at minimum security levels can also be used in the determination of the required authentication security level. The determined security level is preferably a combination of both authentication security and a time limit. The time limit defines an acceptable level of staleness in the authentication, allowing the combined security level either to force the user to authenticate, or to allow a previous authentication. In step 104, the user is authenticated using an authentication mechanism having combination of a security level and time factor at least equal to the determined combined security level. For example, the determined combined security level could be that the user has been previously authenticated using a username and password, has been authenticated within a predetermined time limit previously, the user must authenticate for this transaction using a user name and password pair, a username and password pair in conjunction with another shared secret, or with biometric authentication. The previous list is intended to be exemplary, and in no way should it be considered exhaustive of either of the two dimensions of security or of their combination. Upon successful user authentication, the homesite provides the membersite with a user identity response in step 106. This response preferably contains the requested user information, and a statement from the homesite detailing the security level at which the user was authenticated. One skilled in the art will appreciate that the membersite can include in the user identity request a list of acceptable authentication mechanisms, and the homesite would them determine the required security level by selecting one from the provided list, optionally doing so in accordance with user preferences and homesite policies. Thus, a homesite can use any of a number of authentication methods, and preferably uses the one specified by the membersite. To allow for authentication methods to be properly specified, each authentication method can be assigned a security level, allowing the membersite to request authentication at a desired level. The homesite can then use any authentication method at, or above, that level to authenticate the user. From the perspective of a membersite, when a user visits, the membersite can determine that the user has a homesite, through any number of known mechanisms, including looking for a cookie in a shadow domain. The user can be redirected to the homesite with a request for authentication, possibly including an information request. This request includes an indication of the security level, preferably for both the authentication and the time sensitivity, required. When a response from the homesite is received, the response can include a statement, preferably signed by the homesite, that authentication was performed at a given level either at or in excess of the one specified by the membersite. FIG. 2 is a flowchart illustrating an exemplary embodiment of a method to implement the above-described graduated authentication method from the perspective of the membersite. In step 108, the membersite issues a user identity request containing a defined authentication security level. In step 110, the membersite receives the homesite's user identity response. In step 112, the membersite examines the user identity response to determine the security level at which the user was authenticated. The determined security level can then be compared to the security level defined in step 108. If the level does not meet the requirements, the membersite can handle the error in any number of ways. As an example, if a membersite is a financial institution that in a login procedure obtains the user login information from a homesite, and the membersite specifies that the user must authenticate using a user name and password combination, and receives an identity response that was authenticated on the basis of a previous authentication, the membersite can refuse the user login. The membersite can then present the user with a notice that the homesite did not use the required authentication and then query the user for account information for an out-of-identity-management-network login. As an example of the above described authentication security levels, consider the scenario of a news server that provides users with specified layout and content filtering based on saved user profiles. When a user visits the news server, the server sends the user to the homesite for authentication, and specifies that the lowest form of authentication is required, which in this scenario is that the user possesses a cookie from the homesite indicating that an authentication has occurred in the last 30 days. The homesite receives the user authentication request, determines that the user identifier, such as a globally unique persona identifier or a pairwise unique identifier, can be released without obtaining further user authentication as the user has previously authenticated. The user's identifier, along with a statement that authentication has been performed at or above the desired level, is then provided to the news server in a response signed by the homesite. The news server can then cross reference the user identifier with a set of preferences to display the news content in the desired format. Upon reading a story, the user clicks on a link to purchase a photo associated with one of the news stories. The purchase will be done on a credit card, whose information is stored by the homesite. The news server sends a request for user information to the homesite and requests the user's credit card number and a shipping address. The news server requests that the homesite authenticate the user using at least a username and password combination. The homesite receives the request for user information, and checks the user preferences related to the release of information. These preferences indicate that though the user will release a shipping address from a username and password challenge, a stronger challenge, such as a username and a response to two personal identification questions selected from a pool of questions, must be used to release a credit card number. The homesite then randomly selects two questions from a pool of questions, including information such as birthdate, place of birth, mother's maiden name, a favorite color, and a pet's name. These questions are provided to the user as a challenge. Upon successful completion of the challenge, the information is released to the news server in a signed response that includes an indication that a challenge at least as rigorous as the username password was obtained. Other levels of security can include a biometric or fingerprint scan, an out of band challenge such as a telephone call placed to a designated phone number, an out of band challenge including a password request in the out of band connection, automated token generation systems, and other known authentication mechanisms. One skilled in the art will appreciate that the above list is intended to be exemplary and not limiting in any manner. As a companion to the above authentication security levels, the present invention can optionally provide a series of different channel configurations so that the channel between the membersite and homesite can have different levels of security itself. These two systems can be implemented independently of each other, though in combination they provide a large number of security options. FIG. 3 illustrates the data flow between the browser B 114 of a user, whose identity information is stored by homesite HS 116, when attempting a login to membersite MS 118. B 114 connects to MS 118 over a data connection 120. The degree of security required for the authentication operation can be determined by the needs of the membersite. In transactions that do not require high degrees of security, such as authentications that would otherwise be username and password pairs exchanged in the clear, encryption is not required at either end. As a result, after browser 114 connects to MS 118 over datapath 120, MS 118 requests authentication of the user by sending an authentication request to HS 116. This request is sent to HS 116 by sending an authentication request to B 114 over datapath 112. The request sent to B 114 contains a redirect command that redirects B 114 to HS 116 and sends the authentication request over datapath 126. Thus, the authentication request is sent over a virtual channel created by datapaths 122 and 126 connected by the user redirection shown as 124. HS 116 authenticates the user, using any of a number of techniques as described above, or in the prior art references, and then provides the requested information to MS 118 by sending it, via browser 114, on over the channel created by datapaths 128, 130 and 132. If MS 118 would have otherwise used a simple username and password pair transmitted in the clear, the authentication of the user at HS 116 may be done over a secure channel, but the data provided to MS 118 can be send in the clear over unsecured data path 132. This allows sites that do not require secure connections to belong to the identity management network without supporting secure connections. In a presently preferred embodiment, HS 116 will send a response to MS 118 using the same data connection type that MS 118 sends the authentication request using, unless otherwise specified. Thus, upon receiving the authentication request over unsecured channel 124, HS 116 provides the requested authentication to MS 118 over unsecured channel 130. FIG. 4 illustrates the dataflow for a scenario where MS 118 requests data over an insecure channel and HS 116 is required to send the data over a secure data channel. When making the authentication request, MS 118 may consider that though the confirmation of the user identity is confidential, the request for the information is not. As such, MS 118 may choose to not use a secure channel to request the authentication. MS 118 then transmits an authentication request to HS 116 over the unsecure virtual channel created by datapaths 122, 124 and 126. The request specifies that the response should be transmitted over a secure channel. This allows MS 118 to not cause a redirect to its own secure server at the time of making the request, and instead simply sends the user to HS 116. After authenticating the user of browser 114, and optionally obtaining user authorization, HS 118 redirects the user to MS 118 over secure channel 136. Security for the channel can be provided in any of a number of ways including the use of Secure Sockets Layer (SSL) connections, or the secure hypertext transfer protocol (https). If MS 118 requests more than authentication, and includes a request for user information, such as biographic or financial data, the secure return path 136 provides security for the transmitted data. One skilled in the art will appreciate that if a user specifies that certain data is only to be released over secure channels, HS 116 can, in response to a request, redirect browser 114 to MS 118 to provide the message that the response can only be provided over a secure link. Thus, the user can be guaranteed that confidential information is only provided in secure sessions. In certain attacks on secure servers a “man in the middle” is used, so that requests for information are intercepted, modified, and then passed along. If a man in the middle type attack of this sort is attempted on the system of FIG. 4, HS 116 will receive a request for additional information, but will only send it over a secure channel. Nonetheless, it may be beneficial for MS 118 to be able to easily identify such attacks. To allow for this, a further gradient of security can be introduced. Such a further security gradient is illustrated in the dataflows of FIG. 5. After B 114 connects to MS 118 over connection 120, MS 118 makes an authentication or information request from HS 116, by redirecting B 114 to HS 116 over the virtual channel created by datapaths 122, 124 and 126. After authenticating the user of B 114, and optionally obtaining user approval for the release of information, HS 116 sends the requested information or authentication to MS 118 via B 114, by redirecting B 114 over the virtual channel created by datapaths 140 142 and 144. However, in addition to using a secure channel, HS 116 includes in the response the parameters of the request. MS 118, upon receipt of the response, can then easily identify if the parameters have been modified. This alerts MS 118 to the start of a man in the middle attack. FIG. 6 illustrates a further security level for use in the present invention. The user of browser 114 visits MS 118, and, upon indicating a membership in the identity management network, is redirected to HS 116 along the virtual channel created by datapaths 146, 148 and 150. After authenticating the user, HS 116 transmits the response to the information and/or authentication request to MS 118 over secure the virtual channel created by datapaths 140 142 and 144 along with the request parameters. To provide enhanced data protection, MS 118 uses secure paths 146 and 150 to transmit the request to HS 116 and also signs the request. HS 116 can then verify that the request was signed by MS 118, and has not been tampered with during transmission. If a request has been tampered with, HS 116 can redirect B 114 to MS 118 without the requested information to provide a message that the request was modified prior to receipt. If HS 116 and MS 118 have no other connection to each other, other than belonging to the same identity management network, MS 116 can provide its public key to HS 116 along with the request. To ensure that the signature is not modified, or replaced, during an attack, the signature can be signed by a common trusted party, such as a network root or a trusted certificate authority. To offer the different gradients of channel security, the present invention provides for both membersites and homesites to communicate to each other, preferably through browser 114, using a channel selected from a channel listing. The following listing is meant to be exemplary and is not necessarily exhaustive. The list is not strictly ordered to show increasing security, as certain features of some channels offer security in a different manner than others. At a first level an open channel, with no encryption, can be used between the MS and the HS. To increase the security, and open channel can be used with HS signing the response to show that the content has not been modified in transit. A secure channel can be used, so that transit between the HS and B, and B and MS is secure. A secure channel with a signed response allows HS to have a secure connection to B, and then have a secure channel from B to MS, and allows MS to see that the response has not been modified in transit. An open channel can be used, with both the request and the response signed. This allows HS to know that the request for information has not been tampered with, and allows the MS to know that the response has not been tampered with. If HS passes the signed request back to MS along with the signed response, MS can also verify that the request was not tampered with. The same signed request and response can also be transmitted over a secure channel. By offering a series of these security levels the identity management system of the present invention allows membersites to use the most appropriate security for their needs, and does not force a one size fits all solution upon membersites. Homesites include input ports to receive requests for information and authentication. Prior to release of the information or authentication, a homesite can examine the information to be released and compare it to specified user conditions for the release of that information. Thus, a user can specify a channel security level at which information can be released, similar to the authentication security level settings on information described above. This allows a membersite to make a low security request, and a user preference or homesite policy to override it, and inform the membersite that the requested information can only be released using secure channels. The use of redirect commands allows the HS and MS to pass these messages to each other transparently to the user. Thus, the homesite input ports receive membersite requests, while an authentication engine obtains user authentication, and optionally obtains user authorization for the release of requested information. A homesite response engine then prepares the response to the received request and transmits it to the membersite over either the requested channel, or over a channel required by user preferences or homesite policies. MS 118 is always guaranteed that the message from HS 116 has not been modified when a signed response is sent. The signature can be verified against a signature signed by a trusted third party, such as a network root as described in other references, or by a certificate authority. FIG. 7 illustrates an exemplary method for a homesite to select a channel as described above. In step 152, a homesite receives a user identity request. In step 154, the homesite determines a required channel security level in accordance with the request. As described above the channel can be selected from a list defined a priori. In step 156, the homesite provides a user identity response over a channel having the appropriate security level. As one skilled in the art will appreciate, the determination of a required channel can be done in accordance with both the request and user or homesite defined preferences. As described above, if a membersite requests information over a channel deemed unacceptably low by either homesite or user defined preferences, the homesite can attempt to force the membersite to use a higher security channel by redirecting the user to the membersite with a response that indicates that a more secure channel is required. This response can either simply indicate that a more secure channel is required or it can indicate the minimum channel required. FIG. 8 illustrates an exemplary method for a membersite to specify a channel as described above. The membersite, in step 158, issues a user identity request, which includes a defined channel security level. As described above the channel security level can be selected from a list defined a priori. In response to the user identity request, the membersite receives, in step 160, a user identity response. In step 162, the membersite can examine both the response and the channel, over which the response was received, to determine that the channel has the defined security level. If the membersite requested that the response include a signed set of the request parameters over an unencrypted http channel, an inspection of both the channel and the response will indicate whether or not the response meets the requirements. If the response does not meet the requirements, the user can be informed that the homesite did not respond as expected and that an attack may be in progress on the user's identity. In the alternate the membersite could determine that it is under attack from a malicious third party, and determine that the safest course of action is to terminate the connection and log the IP address of the response sender, which, if the browser was used to redirect the response, should correspond to the user. One skilled in the art will appreciate that the above described channel and authentication security levels can be provided either separately from each other or in tandem. They both rely upon a membersite issuing a user identity request with a defined security level, and the membersite receiving a response that is checked to ensure that it meets the defined security level. From the perspective of the homesite, both method involve receiving user identity requests, determining a security level in accordance with the received request and sending a response that meets the specified security levels. FIG. 9 illustrates the application of the security system described above to allow a membersite to connect to a webservice on behalf of a user to obtain information or to have service performed. In FIG. 9, HS 116, MS 118 and webservice WS 166 all belong to the identity management network operated by root 164. In belonging to the network, each node has trust in root 164, and can identify other nodes in the network by requesting a signature associated with the other nodes that is signed by the root. By offering another node in the network a public signature block that is signed by the root, a node can establish both that it is part of the network, and that any transmission that it makes has not been tampered with. When the user of browser 114 establishes a session with MS 118, over connection 168, an authentication with HS 116 takes place (not shown as part of the data flow). After authentication, the user may request a feature provided by MS 118 that requires access to a webservice, such as WS 166. As an illustrative example, not intended to limit the scope of the invention, MS 118 may offer a financial portal service to the user of browser 114, whereby MS 118 collects financial information from a number of other servers and presents it to the user in a consolidated format. WS 166 can match a globally unique persona identifier (GUPI) with the user of browser 114 and the services to which the user is subscribed. MS 118 provides a request to WS 166 over datapath 170. WS 166 sends a request 172 to MS 118. This request typically includes a request for user authentication and a set of information to allow WS 166 to identify the user. The request from WS 166 can also include requests for assertions from third parties that are held by the homesite 116. Such assertions can include verifiable statements that a user is a member of an organization, such as a reward program, and even that the user has obtained a status level in the organization. Other assertions may be issued by governmental organizations indicating that a user has a geographical location. Those skilled in the art will appreciate that any number of third party assertions can be provided to WS 166. This request is preferably accompanied with a nonce or other form of session identifier so that MS 118, or another system, is prevented from using the user authentication as part of a replay attack. MS 118 forwards the request for authentication to HS 116 by redirecting the user along logical datapath 174, one skilled in the art will appreciate that datapath 174 can include multiple channels established between different nodes on a point-to-point basis. The request from MS 118 to HS 116 may simply be the WS 166 request, or it may include a series of requests, including an aggregation of requests from the number of other web services (not shown). Furthermore, the request sent along datapath 174 may include other information needed by MS 118. The request relayed to HS 116 preferably contains a request for a set of information about the user, user authentication, and an explanation of what information is being provided and why it is being requested. In a presently preferred embodiment, the explanation is provided both as plaintext so that HS 116 can easily display it to the user, and as a programmatic explanation, so that HS 116 can obtain one-time authorization for the release of the information to WS 166. The programmatic explanation, if provided, allows HS 116 to simply perform a compare operation on existing authorizations, reducing the number of times that the user must interact with HS 116, increasing the appearance of a seamless experience. Upon obtaining user authorization and authentication, HS 116 prepares a response, signs the response and includes its public signature, signed by root 164. If the request from MS 118 is an aggregation of requests from multiple webservices, HS 116 can sign each corresponding response separately so that each webservice is provided with only the information that it requested. In an alternate embodiment, to reduce the computational overhead on HS 116 imposed by signing multiple data blocks, the entire response is signed, and each web service is provided the whole response. The response is sent to MS 118 via browser 114 over datapath 176. MS 118 preferably breaks the response into the separately signed segments and forwards each segment to the respective WS. WS 166 then receives its request on datapath 178. WS 166 can then authenticate that the data has not been modified in transit by examining the homesite signature and knowing the root signature. The use of a nonce, as described above, provides WS 166 the ability to track when the request was issued if a timeout value is to be applied. WS 166 can match information in the response from HS 116 to information held, such as bank account information, to determine which information to release to MS 118. Upon validating the authorization and gathering the information to release to MS 118, WS 166 sends the information to MS 118 over datapath 180. Upon receipt of the information from WS 166, MS 118 can act on the information as required. Depending on the content of the response, WS 166 may select the elements of the signed response that it needs and then examine the authorization it has received. If authorization has been received WS 166 will either provide a token to MS 118 that permits multiple access without further authentication, or will provide the requested information to MS 118 without a token to provide one-time access only. For the purposes of an example, not intended to limit the scope of the present invention, the following scenario is presented. A user directs browser 114 to MS 118, where a session has already been established. MS 118 provides the ability to aggregate information, such as travel information, for a user. MS 118 has knowledge of the user's upcoming travel itinerary, and proceeds to connect to an airline travel webservice, WS 166. WS 166 upon receiving the initial contact from MS 118 provides a request for authentication of the user, using datapath 172, and requests the user's full name, address and frequent flier information. This request is forwarded to HS 116, possibly along with other information requests, following datapath 174 through MS 118, and browser 114. Upon receipt of the request, HS 116 requests that the user re-authenticate. The request from WS 166 is accompanied by both a text explanation outlining the information that is going to be released and a programmatic explanation; so that at a later date the user does not need to interact with HS 116, and HS 116 can simply send the response. After authentication and acceptance of the release of the information, the user authorizes HS 116 to release the information to WS 166. HS 116 then prepares a response including a user identifier, such as a GUPI, the requested information, and a nonce provided with request. The response is signed by HS 116, and a root-signed copy of HS 116's public signature is appended to the signed response. This response is forwarded to MS 118 via browser 114 by redirecting the browser, along the continuation of datapath 176, using any of a number of known techniques. MS 118 then forwards the segment of the signed response corresponding to the request from WS 166 to WS 166 over datapath 178. After verifying the nonce and the requested information, WS 166 obtains the flight information for the user, provides it to MS 118, and allows any of a number of functions to be provided including seat selection and advance check-in with electronic boarding pass provisions. One skilled in the art will appreciate both that other services can be provided, and that MS 118 can connect to a plurality of webservices to aggregate data from each of them. In one embodiment of the present invention, MS 118 requests sessions with a plurality of webservice providers, and aggregates their information requests. The aggregated requests are then provided en masse to HS 116, and user authorization for all requests is obtained at once. This allows HS 116 to provide a series of responses to MS 118, at which time MS 118 then separates the responses and sends each of the individual responses to the respective webserivce providers. The severing of the concatenated responses from HS 116 can easily be managed using the session identifiers issued by each webservice provider as a key. In alternate embodiments, HS 116 obtains user approval for the release of the information to each of the webservice providers, and then sends the responses one at a time to MS 118, which after receiving a response simply redirects browser 114 to HS 116 to obtain the next response until all responses are obtained and forwarded to the webservice providers. One skilled in the art will appreciate that the actual mechanism used for the supporting of multiple webservice providers can vary without affecting the scope of the present invention. Webservice providers, such as WS 166, can relate the information that they requested to their database, and at the same time be assured that they are allowed to release the information, as HS 116 can be proven to be authoritative for the user's identifier by following a signature key chain through any number of delegations until a trusted source is used to show that HS 116 is authoritative for the information released. Some of the information housed by HS 116 may be provided to it by an outside authoritative source as described in detail in related applications, such as Canadian Application Numbers 2,468,351, and 2,468,585, which are hereby incorporated by reference. In cases where the information, such as a frequent flier number, is housed by an external authoritative site, HS 116 can provide the externally signed assertion to WS 166, allowing WS 166 to determine both that the information provided is authentic, and that HS 116 is authoritative for the user associated with the information. One skilled in the art will appreciate that MS 118 may always connect to WS 166. As a result, MS 118 can, upon receiving an indication that the user is part of the identity management system, initiate the connection to WS 166 to request a session over datapath 170. When MS 118 requests information required by WS 166, it can include its own user authentication request. Thus, authentication of the user at HS 116 can be done at the same time that the user authorizes the release of information to WS 166. As illustrated in FIG. 10, HS 116 is authoritative for the user of browser 114. As such, HS 116 can be used as an agent of the user and permitted to directly interact with WS 166. In such a scenario HS 116 directly connects to WS 166, and requests information using connection 182. WS 166 uses a standard interface, and as a result does not notice a difference between HS 116 and MS 118. Because HS 116 is already authoritative for the user, the authentication and data passing through MS 118 can be bypassed. WS 166 can issue an authentication request 184, which HS 116, acting as an agent for the user, can directly respond to over connection 186. WS 166 can then either issue a token or one-time-information 188. The user's trust of HS 116 allows for this scenario to be permitted, as without user approval HS 116 will not interact with WS 166. A rich client can be provided that interacts with WS 166 on the user's behalf without having to interact with MS 118, as illustrated in FIG. 11. As an example, if WS 166 provides financial information to users for a bank, the bank can provide users with a rich client (RC) 190 that will interact with WS120. The client is preferably a non-browser based application that can make calls to WS 166. Due to its standardized interface, WS 166 is agnostic as to who interacts with it. RC 190 appears as another MS to WS 166. When RC 190 issues a request 192 to WS 166, it receives a request for authentication and information 194. RC then launches a browser 114 from the local computer, and uses the browser 114 to transmit WS 166's request to HS 116 over datapath 196. The user interacts with HS 116 in the normal manner, and approves the release of the information. The response 198 is sent from HS 116 to the browser 114, which provides the information to RC 190. RC 190 can then close the browser window, and forward the requested information to WS 166 over datapath 200. RC 190 can obtain the requested information from the browser 114 prior to closing the window, by having the browser 114 redirected to the localhost address at a predetermined port. As long as RC 190 has control over that port and is listening on it, the information can be received and then sent along to WS 166. WS 166 can then send the requested information, or a token, to RC 190 over datapath 202. To facilitate the interaction of RC with the rest of the network, RC can use a public API to interact with network nodes such as HS 116 and WS 166. As new standards for connection are defined, or new node types arise, the API can be changed by a public administrator, and then provided to the users of RC. By replacing the API, the ability to connect either to new node types or to existing nodes in a new manner can be provided without requiring the rewriting of the code base for RC. As described above, the network root administers admission to the network, and provides signed assertions that a homesite is authoritative for a user. Each user is uniquely identified by both a GUPI and an email address. By leveraging the trust model of this network, a distributed contact management network is provided. At present contact management networks require a single database of contacts that are maintained by a sole provider. The distributed nature of the network of the present invention bypasses the drawbacks to that model. A distributed contact management system in the network of the present invention is illustrated in FIG. 12. Root 164 maintains a database 204 mapping email addresses to associated GUPI's and homesite identifiers used to identify the homesite that is authoritative for the GUPI. HS 116 is authoritative for a GUPI associated with the user of browser 114. The user of browser 114 provides to HS 116 a listing of known contacts over datapath 206. HS 116 extracts the email addresses from the contact listing and provides the email addresses to root 164 over datapath 208. Root 164 then identifies the GUPI and homesite associated with each submitted email address, and provides this information to the HS 116 over return datapath 210. HS 116 can then contact HS2 212, which is authoritative for a GUPI associated with one of the submitted email addresses over connection 214. When HS 116 contacts HS2 212 over datapath 214, it can request additional contact information stored by HS2 212. HS2 212 can release this information, if authorized by the relevant user, or can ask the relevant user for authorization at the next login. When providing the information, HS2 212 can provide a URI to HS 116 allowing HS 116 to obtain updated information at other times, so that the contact information can be updated periodically. Conversely, HS 116 can provide HS2 212 with a URI so that when the requested information changes, or at fixed intervals, HS 116 will receive updated information over datapath 214. After receiving the user information over datapath 214, HS 116 can forward the information to browser 114 over datapath 216. One skilled in the art will appreciate that a number of other software applications, other than a standard internet web browser, can be used by the user to communicate with HS 116 including email and contact management clients. In the above scenario the contact information can be transmitted in any of a number of formats including the virtual card (vcard) standard. The above-described scenario allows homesites to communicate to each other using URI's to update information. A similar network service is illustrated in FIG. 13, where HS 116 is provided with an update URI by MS 118, through browser 114 during a request for information over datapath 218. The requested information is provided to MS 118 over datapath 220. Both channels 218 and 220 make use of the redirection of browser 114. However, when the supplied information changes, and if the user has approved the updating of information, HS 116 can create a back channel connection 222 to MS 118 to supply the updated information. One skilled in the art will appreciate that in addition to the request interface described above, a homesite would preferably have an update interface or engine, to allow monitoring of information for a user, so that when a user modifies a profile, the relevant information can be updated by backchannel, without requiring user interaction with the membersite. FIG. 14 illustrates the use of the update URI for a user who is changing from HS 116 to HS2 212 as a principal identity store. As in the example of FIG. 13, HS 116 has obtained an update URI associated with MS 118 over datapath 218, and has provided contact information to MS 118 over data path 220. The user, through browser 114 over datapath 224, informs HS 116 that the GUPI, and all associated information, is to be transferred to HS2 212. This can be a permanent transfer of information, or it can be using one homesite to serve as a backup to another. HS 116 connects to HS2 212, either directly over a back channel, or through redirection of the browser 114, and an exchange of data is made. This datapath is shown as datapath 226, which is an example of a back channel connection, but one skilled in the art will appreciate that it can be performed using browser redirection. Along with the user information associated with the GUPI, HS 116 transfers the update URI from MS 118 to HS2 212. Thus, when HS2 212 receives updated information from browser 114 the information can still be updated with MS 118 seamlessly over datapath 228. GUPI's are typically assigned by root 164 to a homesite, such as HS 116. Thus far in identity management systems, each identifier is linked to an email address. This removes the ability of a user to be anonymous, as the identifier can be associated with an email address that is easily traceable to a user. To satisfy the need for anonymous personas, root 164 can assign a series of GUPIs to HS 116 as an anonymous pool. This allows HS 116 to provide a user with a pool of anonymous GUPIs, so that if a user wishes to remain anonymous, HS 116 is the only site that can identify the user. Once again, this model is predicated upon the user of browser 114 having trust in HS 116, without which, HS 116 would never be able to server as a homesite that stores the user's identity information. With a sufficiently large pool of anonymous GUPIs, HS 116 can assign a different GUPI to each site that a user visits. Though this prevents the building of attributes that can establish a virtual reputation, the purpose of anonymous personas is to prevent the building of any reputation. Because no two sites will be given the same GUPI, the result is much the same as a pairwise unique identifier, however, HS 116 can, in one embodiment, economize on GUPI's in the unique pool by allowing the same GUPI to be used by two different users at two different sites. Because the GUPI has no attributes associated with it, and no user can build a reputation with it, if treated communally it further anonymizes the behaviour of the user. In non-shared embodiments, HS 116 must track the pairings of the membersite identifier and the user to determine the GUPI to be used. If the GUPI is not shared, it is still globally unique, and can be ported to another homesite. When transferring persona information to another homesite, the user can obtain a GUPI list from the homesite and can have the authoritativeness of that GUPI transferred to another homesite. For the embodiment where GUPIs are communally shared, the new homesite can be made authoritative for the GUPI, maintaining the same membersite identifier and user pairing to associate to the GUPI, without revoking the authoritativeness of the original homesite, as other people at other sites may use the GUPI. One of the issues that arise from using multiple GUPI to allow a user to keep persona separate, is that when assertions are made, they are typically made for a single persona. Thus, for a user with home and office persona, an assertion may be made for the office persona regarding membership in an organization. If the user's home persona needs to make use of the membership assertion attached to the office persona there are two mechanisms provided by the present invention for this. Using a first mechanism, a user can direct HS 116 to contact AS which issued the assertion for the work persona. HS 116 then provides AS with multiple GUPIs, and the assertions for any of the provided GUPIs issued by AS and indicates that it is authoritative for all the submitted GUPIs, and all the submitted GUPIs are the same individual. AS, upon being informed that all the GUPIs are issued to the same individual, can then provide any GUPIs that do not have an assertion, with the assertion provided by HS 116. In an example, AS is a frequent flier program, and has provided an assertion indicating that the office persona of a user has obtained elite status. HS 116 provides the GUPIs for the user's office and home persona to AS along with the assertion that the office persona has obtained elite status. AS then verifies that HS 116 is authoritative for both GUPIs, and confirms that the office persona is certified as having elite status. AS then provides an assertion for the GUPI associated with the home persona indicating elite status. This allows for assertions to be shared between persona, but comes at the cost of having AS know that two GUPI are related to each other. If a user wishes to avoid having two GUPI linked together by an AS, but one GUPI has an assertion needed by the other GUPI, the following method can be employed. When MS 118 requests an assertion about a first GUPI that is only held by a second GUPI, HS 116 can include in its signed response, both GUPIs, and the assertion held for the second GUPI. MS 118 can then determine from the response, that HS 116 is authoritative for both GUPIs, and sees that HS 116 states that both GUPIs are issued to the same person. MS 118 can then verify that the second persona has the required assertion, and apply the assertion to the first persona. As an example, a user with office and home persona has an assertion for the office persona that indicates elite status in a frequent flier program from AS. The user wants to use this assertion with the home persona when visiting MS 118. In response to MS 118's request for the assertion, HS 116 sends both office and home GUPI, and the assertion for the office persona GUPI. MS 116 can then verify that the GUPIs are related, and can transitively apply the assertion to the home persona. In contrast to the first embodiment, AS does not know that the persona are linked, but MS 118 knows. Because the operation, by default, includes moving attributes from one persona to another, HS 116 must reveal the link between 2 GUPIs to at least one of the two. By offering both mechanisms, the user is provided the opportunity to choose which node in the network is shown the link. The above described method and system for sharing credentials between GUPIs can also be used in relation to anonymous GUPI, though it should be noted that this reduces the anonymity of a GUPI, so should preferably not be done with a GUPI shared among users. For a MS 118 that has only ever been presented with an anonymous GUPI, the above-described method provides a method of transferring history to an identifiable GUPI. If HS 116 provides MS 118 with both an anonymous GUPI and an identifiable, or non-anonymous, GUPI, MS 118 can transfer any history associated with the anonymous GUPI to the identifiable GUPI. This allows a user to interact with MS 118 in an anonymous fashion, and then, having reached a comfort level with MS 118, the user can present another GUPI and have any history and reputation transferred to the non-anonymous GUPI. To increase the availability of homesite management capabilities, a homesite can be built-in to a browser. Such a homesite can be offered either as an integral part of a web browser, or can be offered using a plug-in architecture. Such a plug in, or integrated browser, can be used to simplify the communication with nodes in the network and reduce the redirection of previous embodiments. At a first level, a browser can indicate that it understands extensions to HTML specific to the identity management network. When browsers make requests from web servers using the hypertext transfer protocol (http), they provide an indication of capabilities, including an HTML version. By indicating that the browser understands the identity management network extensions to HTML (or identity management HTML tags), MS 118 does not need to redirect the browser to the shadow domain to find out the homesite of the user. Instead, MS can simply send an HTML instruction to the browser to obtain user authentication. If the browser indicates that it is both identity management aware, and that a homesite has been configured, MS 118 need only provide authentication and information requests to the browser, and the browser will then handle any redirection needed. This allows MS 118 to avoid using redirections to shadow domains to find out what the user's homesite is, and avoids having to issue redirection requests to the browser. From the perspective of the user, fewer redirection requests are issued, and MS 118 never obtains the location of the users' homesite. If MS 118 simply instructs the enhanced browser to obtain authentication in an HTML tagged message, it does not need to tell the browser where to redirect to, and avoids using javascript™ redirects and close window commands to make the user experience seamless. The MS only determines the user's HS, when a response is issued, which increases user privacy. As an enhancement, an enhanced browser can also be provided with the ability to function as a homesite. As disclosed in the above-cited references, a homesite can be provided as a local application. By integrating the homesite within the web browser, redirection can be avoided. When the HS-enabled browser visits MS 118, it indicates that it supports identity management HTML tags. MS 118 then instructs the browser to obtain user authentication and return user information. HS-enabled browser no longer needs to redirect to an external site, and instead can provide user authentication using a locally controlled authentication tab or window. If the user has specified that use of the browser is a sufficient indication of authentication, HS-enabled browser can immediately return the requested information, having signed the response. This eliminates the user having to interact with an external homesite, and reduces the data transmission, which is especially important on low-bandwidth connections. The HS-enabled browser preferably does not have a homesite cookie, so that MS 118 will not know that the user is using a local homesite. One skilled in the art will appreciate that when an identity management aware browser sends identity management information through http headers, it allows MS 118 to refrain from bouncing the browser to the shadow domain. This allows MS 118 to simplify its interaction with the browser, as the browser has indicated that it knows a homesite for the user. Instead of the MS being sent the HS identifying information, MS uses an http command to request authentication in a POST command. The browser will handle redirection if needed and will replace the request authentication command with the appropriate HTML if an external HS is used. If an external HS is used, it can identify that it does not need to use a redirect command to send the information to MS, and instead simply sends the response to the browser and tells the browser to send the information to the MS. The above-described enhancement to a browser can either be integrated into the browser code, or can be provided as a plug in. One skilled in the art will appreciate that either embodiment can communicate with a root node to obtain updated schema, or can obtain the updated schema from a central service used to ensure that the browser has been updated to the most recent patches and bug-fixes. One skilled in the art will appreciate that the homesites, webservices and membersites of the present invention can all be implemented on standard computing hardware using known software techniques to implement the methods of the present invention. These systems typically include an input to receive requests from external nodes, a processor for examining the request and for acting upon the request in accordance with the methods of the present invention, and an output for issuing both requests and responses as needed or required by the methods of the present invention. The implementation of the methods of the present invention on such hardware, using either conventional software or firmware, are well within the scope of one of skill in the art. The above-described embodiments of the present invention are intended to be examples only. Alterations, modifications and variations may be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto. | <SOH> BACKGROUND OF THE INVENTION <EOH>In the field of identity management, there are a number of known systems for providing user identity services on the Internet. Microsoft's Passport™, and the Liberty Alliance identity management system are two such known examples, as are the identity management systems taught in Canadian Patent No. 2,431,311, and Canadian Patent Application Nos. 2,458,257, 2,468,351, and 2,468,585. Many known identity management systems offer secure logins, allowing a user to visit a site in the network (membersite) and obtain a secure login to that site using an identity store to authenticate the user identity over a secure channel. The use of a secure channel allows an identity store to provide the membersite with user login information and/or confidential user information. However, the reliance on secure channels increases the barrier to entry for membersites. Under a secure setup, lightweight, or simple, login is encumbered by the overhead of a secure channel. In an identity management system that relies upon homesites to act as an identity store which stores user identity information, it may be advantageous to provide a form of graduated security to allow a membersite to obtain identity information, including authentication, using a number of different channels, each with different security features. There is a further need for a mechanism through which a webservice provider can obtain user authentication and authorization for a third party to receive information. At present, if a third party wishes to aggregate information from a number of webservice providers for the user, or if a third party requires information from a webservice provider to further process before providing the results to a user, the third party and the webservice must be heavily linked. Typically, the third party must become associated with the webservice, and have its services bundled by the webservice provider. Thus a financial institution can use an aggregation service to perform analysis on a client's holdings, but a client cannot easily obtain an aggregation across a number of financial institutions. There is therefore a need for a mechanism for third parties to provide authentication of a user authorization for release of information provided by a webservice. There are at present a number of contact management services that allow a user to provide a list of known contacts. If the contacts provided a user subscribe to the same service, when one of the users updates a segment of a profile, the change is automatically reflected in the other users contact list. However, at present, these services are highly centralized. There is no automated mechanism to obtain information about users that have not subscribed. There is a plurality of these services, and at present there is no convenient mechanism for data exchange between them. This results in users forming small collective islands of contact sharing. There is a need for a distributed contact management system that allows users to share information with people in a vast identity management system that allows for automated updating of contact information. It is, therefore, desirable to provide an identity management system that can provide at least one of improved gradations in the security levels, support for third party webservices and support for distributed contact management. | <SOH> SUMMARY OF THE INVENTION <EOH>It is an object of the present invention to obviate or mitigate at least one disadvantage of previous identity management systems. In a first aspect of the present invention, there is provided a method of obtaining contact information from a node in an identity management network. The method comprises receiving a homesite identifier and a user identifier associated with an email address; requesting from a homesite associated with the received homesite identifier contact information for a user associated with the received user identifier; and receiving from the homesite associated with the received homesite identifier the requested contact information. In an embodiment of the first aspect of the present invention, the method further includes the step of forwarding the received contact information to a user. In another embodiment, the step of receiving a homesite identifier includes receiving the homesite identifier and user identifier from a network root and is optionally preceded by the step of transmitting a request for a user identifier and a homesite identifier associated with an email address. In these embodiments, the user identifier can be a globally unique persona identifier. In another embodiment, the step of receiving the requested contact information is preceded by obtaining approval for the release of the contact information from the user associated with the requested contact information. In another embodiment, the step of receiving the requested contact information includes receiving a universal resource indicator for receiving updated contact information. In a second aspect of the present invention, there is provided a method of authorizing a webservice provider to release information, associated with a user, to a third party. The method comprises the steps of receiving from the webservice provider a request for user authentication and authorization to release information to the third party; authenticating the user and obtaining user authorization for the release of the information; and forwarding to the webservice provider authorization from the authenticated user to release the information to the third party. In an embodiment of the present invention, the received request from the webservice provider is received via the third party. In another embodiment, the received request includes an explanation of the information to be released to the third party, the explanation preferably includes a text explanation to be shown to the user prior to obtaining user authorization and a programmatic explanation. In another embodiment, the received request includes a nonce and the step of forwarding includes forwarding the nonce along with the response. In another embodiment, the step of forwarding includes signing the response, appending proof of authoritativeness for the user and forwarding the authorization to the webservice provide via the third party. Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. | 20050124 | 20130806 | 20060105 | 90300.0 | G06F1730 | 0 | ZHANG, SHIRLEY X | DISTRIBUTED CONTACT INFORMATION MANAGEMENT | UNDISCOUNTED | 0 | ACCEPTED | G06F | 2,005 |
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11,039,948 | ACCEPTED | Method for processing noise interference | A method for processing noise interference in a serial AT Attachment (SATA) interface. The method includes the steps of detecting whether there is an error in CRC (Cyclic Redundancy Check) checksum or whether an R_ERR primitive (reception error primitive) is received, detecting whether a FIS (Frame Information Structure) is a data type if there is any error and returning back to error state detecting step if there is no any error, detecting whether the FIS is a ATAPI packet command CDB (Command Descriptor Block) when the FIS is the data format, and writing a special tag to the CDB and returning back to the error detecting step. | 1. A method for processing noise interference in a data accessing device with a SATA (Serial Advanced Technology Attachment) interface, the method comprising: an error detecting step for detecting whether there is a CRC (Cyclic Redundancy Check) error, whether an reception error primitive (R_ERR primitive) is received, whether an improper primitive is received, or whether a LINK layer error is detected, and repeating this step if there is no any error; a type detecting step for detecting whether an incoming FIS (Frame Information Structure) is a data type FIS and going back to the error detecting step when the FIS is not data type; a responding step for asserting the CHECK bit of the ATAPI Status Register when the incoming FIS is data type; and sending back the response. 2. The method according to claim 1, wherein the responding step further comprising asserting the ABRT bit of the ATAPI Error Register. 3. The method according to claim 1, wherein the method is used in an optical storage device connected to the SATA interface. 4. The method according to claim 1, further comprising: an ATAPI (AT Attachment with Packet Interface) packet command detecting step for detecting whether the incoming FIS is an ATAPI packet command when the FIS is data type, and executing the responding step if the FIS is the ATAPI packet command; and a DMA (Direct Memory Access) mode data transfer detecting step for detecting whether there is a DMA mode data transfer when the data FIS is not the ATAPI packet command, and executing the responding step if there is not a DMA mode data transfer. 5. The method according to claim 4, wherein the method is used in an optical storage device connected to the SATA interface. 6. The method according to claim 4, further comprising: a request sense command detecting step for detecting whether the present command is a request sense command when there is a DMA mode data transfer; setting a sense key of the ATAPI Error Register to 11 and executing the responding step if the present command is the request sense command; and setting the sense key of the ATAPI Error Register to 4 and executing the responding step if the present command is not the request sense command. 7. The method according to claim 6, wherein the method is used in an optical storage device connected to the SATA interface. 8. The method according to claim 1, wherein the error state detecting step is performed in a link layer. 9. The method according to claim 8, wherein the method is used in an optical storage device connected to the SATA interface. 10. A method for processing noise interference in a data accessing device with a SATA (Serial Advanced Technology Attachment) interface, the method comprising: an error detecting step for detecting whether there is a CRC (Cyclic Redundancy Check) error, whether an reception error primitive (R_ERR primitive) is received, whether an improper primitive is received, or whether a LINK layer error is detected; a type detecting step for detecting whether an incoming FIS (Frame Information Structure) is a data type FIS when there is an error; a step for detecting whether the FIS is a ATAPI CDB (Command Descriptor Block) when the FIS is the data type; and a step for setting a special mark on the CDB, or on any ATAPI Register if the incoming FIS contains a CDB when there is an error. 11. The method according to claim 10, wherein the method is used in a bridge solution, which connects a device with the serial ATA interface to a device with the parallel ATA interface. 12. The method according to claim 11, further comprising: a step for detecting whether it is a DMA (Direct Memory Access) mode data transfer when the present data FIS does not contain the ATAPI CDB; and a step for generating an erroneous CRC (Cyclic Redundancy Check) code when data is being sent to a device with a parallel ATA interface when it is a DMA mode data transfer. 13. The method according to claim 10, further comprising, before the step of detecting whether it is a DMA mode data transfer, the steps of: detecting whether the length of the payload of the present data FIS is correct when the FIS does not contain the ATAPI CDB; and adjusting the length by inserting or discarding data so as to make the data length correctness when the data length of the FIS is incorrect. 14. The method according to claim 13, wherein the method is used in a bridge solution, which connects a device with the serial ATA interface to a device with the parallel ATA interface. 15. The method according to claim 10, wherein the error detecting step is performed in a link layer. 16. The method according to claim 15, wherein the method is used in a bridge solution, which connects a device with the serial ATA interface to a device with the parallel ATA interface. | This application claims the benefit of the filing date of Taiwan Application Ser. No. 093111174, filed on Apr. 22, 2004, the content of which is incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a method for processing noise interference, and more particularly to a method for processing noise interference according to an error feedback mechanism of an ATA/ATAPI (AT Attachment with Packet Interface). 2. Description of the Related Art The serial ATA (Serial Advanced Technology Attachment, hereinafter referred to as SATA) is an interface specification commonly promoted by the companies of APT, Dell, IBM, Intel, Maxtor, Seagate, etc. The SATA specification is applied to the transmission interface of a hard disk drive or an optical disk drive to replace parallel ATA/ATAPI interface that has been used for a long time. The SATA interface specification specifies two pairs of differential signal lines to replace the original 40 or 80 signal lines connected in parallel. Serializing the original data can reduce the size and voltage and increase the speed. The specification also introduces some new functions, such as flow control and error resending, to control the data stream in a simple way. FIG. 1 is a schematic illustration showing communication layers in the SATA specification. As shown in FIG. 1, the SATA interface connects a host 11 to a device 12. The device 12 may be an optical storage device or a hard disk drive, or other devices with the SATA interface. The communication layers in the SATA specification include four layers, which are respectively a first layer (physical layer), a second layer (link layer), a third layer (transport layer) and a fourth layer (application layer). The physical layer is responsible for converting digital and analog signals. That is, the physical layer receives and converts a digital signal sent from the link layer into an analog signal and sends the analog signal to the other end. The physical layer also receives and converts the analog signal, which comes from the other end, into a digital signal and outputs the digital signal to the link layer. The link layer encodes and decodes the digital data. That is, the link layer encodes the data coming from the transport layer and outputs the encoded data to the physical layer. On the other hand, the link layer decodes the data coming from the physical layer and outputs the decoded data to the transport layer. The transport layer constructs and deconstructs the FIS (Frame Information Structure). The detailed definition of the FIS can be found in the SATA specification. The application layer is in charge of buffer memory and DMA engine(s). During the serializing process, the sending device converts the parallel data (e.g., data in bytes or words) into a serial bit data stream. In addition to the typical data, the SATA specification defines some data control codes with four bytes, which are referred to as primitives, for controlling the sending and power management of the sending device and the receiving device. For example, a X_RDY primitive (transmission data ready primitive) represents that the sending device is ready to send data, and a R_RDY primitive (receiver ready primitive) represents that the receiving device is ready to receive data. FIG. 2 is a schematic illustration showing a packet sent through the SATA interface. Two devices communicate with each other to send the packet according to the X_RDY primitive (transmission data ready primitive) and the R_RDY primitive (receiver ready primitive). Then, the sending side sends a packet content, which is packed by a SOF primitive (start of frame) and an EOF primitive (End of frame). After the packet content is sent completely, the sending side sends a WTRM primitive (wait for frame termination primitive). If there is no any error about the CRC (Cyclic Redundancy Check) check in the link layer, the receiving side responds with a R_OK primitive (reception with no error primitive) after it receives the WTRM primitive. If there is an error about the CRC check, the receiving side responds with a R_ERR primitive (reception error). The FIS is for transferring the task file register and data. Two examples will be described in the following. FIG. 3 is a schematic illustration showing a task file register FIS from a host to a device. That is, a task file register written from the host to the device is shown in FIG. 3. FIG. 4 is a schematic illustration showing a data FIS from the host to the device or from the device to the host. That is, the data sent from the host to the device or from the device to the host is shown in FIG. 4. In order to prevent the error caused by noises, the SATA specification specifies a resending mechanism. Almost all type of FISs (e.g., Register-Host to Device FIS or Set Device Bits-Device to Host FIS) are resent when a R_ERR primitive was received so as to ensure that the receiving device can receive the correct control information. However, the data FIS does not have this protection mechanism. When the data error occurs, the device cannot be protected by the resending mechanism under the condition of noise interference because the data FIS is not resent. Thus, the error data may be received. In a more serious condition, some portions of primitives may be mistaken as data bits, thereby making the number of data sets to be sent to the device greater than it should be. In some cases, this error may halt the system. In addition, in the device (e.g., an optical storage device) using the data FIS to send the ATA/ATAPI CDB (Command Descriptor Block), the CDB cannot be protected according to the resending mechanism because the data FIS is not resent. Thus, the device receives an abnormal control command, which causes a larger influence than in the case of sending the normal data using the data FIS. SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a method for processing noise interference in order to prevent the system from being stopped when the data FIS is interfered by noises. To achieve the above-mentioned object, the invention provides a method for processing noise interference. The method includes the steps of detecting error states by detecting whether a CRC (Cyclic Redundancy Check) code exists error or whether an error primitive is received, detecting whether a FIS (Frame Information Structure) is a data format if there is an error state and returning back to error state detecting step if the FIS is not a data format, detecting whether the FIS is a CDB (Command Descriptor Block) when the FIS is a data format, and modifying contents of the CDB, and writing a special mark to the CDB and returning back to the error state detecting step when the FIS is not a CDB. The method of the invention further comprises the steps of: detecting whether a data length of the FIS is correct when the FIS is not the CDB; adjusting the data length by increasing or decreasing data of the FIS so as to make the data length of the FIS correct when the data length of the FIS is incorrect; and generating an error CRC code and jumping back to the error state detecting step. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration showing communication layers in the SATA specification. FIG. 2 is a schematic illustration showing a FIS sent through the SATA interface. FIG. 3 is a schematic illustration showing a task file register FIS from a host to a device. FIG. 4 is a schematic illustration showing a data FIS. FIG. 5 is a flow chart showing a method of the invention for processing noise interference in an ATA/ATAPI device. FIG. 6 is a schematic illustration showing definitions of each bit in an ATAPI Feature Register. FIG. 7 is a schematic illustration showing definitions of each bit in an ATAPI Error Register. FIG. 8 shows definitions of each bit in an ATAPI Status Register. FIG. 9 is a flow chart showing a method of the invention for processing noise interference in a bridge solution. DETAILED DESCRIPTION OF THE INVENTION The invention will be described with reference to the accompanying drawings. The invention utilizes the ATA/ATAPI error feedback mechanism to overcome the problem of system halt caused by noise interference when the data FIS is being sent. A native serial ATA device and a bridge solution may be used according to the real applications. The native serial ATA device directs to a device having a serial ATA interface serving as the data transmission interface without the conversion from the parallel ATA to the serial ATA. The bridge solution can convert the parallel ATA interface to the serial ATA interface so as to provide a solution in a transitional stage. FIG. 5 is a flow chart showing a method of the invention for processing noise interference in a native ATA/ATAPI device. The flow chart illustrates the implementation of advanced processing when there is a CRC error in the link layer or the link layer receives a R_ERR primitive. The method of the invention for processing the noise interference will be described with reference to FIG. 5. Step S502 is to detect whether the link layer has detected an error state. The error state includes the CRC error, the receiving of the R_ERR primitive, or the receiving of the improper error primitive. If the link layer has not detected any error state, step S502 is repeated. If the link layer has detected an error state, the process jumps to step S504. Step S504 is to judge whether the FIS is a data type FIS. As shown in FIGS. 3 and 4, the first byte (Byte 0) of each FIS is the FIS type. If the first byte is 46H, it represents that the FIS is a data type FIS, and the process jumps to step S506. If the first byte is not 46H, the process returns back to step S502. Step S506 is to judge whether the FIS is an ATAPI packet command. When the host wants to send the packet command to the optical storage device, the host firstly sends the task file register FIS with the command register value of A0H to the optical storage device. So, when the optical storage device receives the command register value of A0H, it knows that there are subsequent 12 bytes of ATAPI packet commands. The first byte is the operation code, and the subsequent 11 bytes are the supplement data. If the FIS is an ATAPI packet command, the process jumps to step S516. Otherwise the process jumps to step S508. Step S508 is to judge whether the FIS is a DMA (Direct Memory Access) mode data transfer. FIG. 6 is a schematic illustration showing definitions of each bit in an ATAPI feature register. As shown in FIG. 6, bit 0 (D0) is the DMA mode. Thus, whether the DMA mode data transfer exists may be detected as long as the data of bit 0 of the feature register is asserted. The definitions and functions of other bits may be found in the ATAPI specification. If the FIS is not a DMA mode data transfer, the process jumps to step S516. If the FIS is a DMA mode data transfer, the process jumps to step S510. Step S510 is to judge whether there is a request sense command (packet command with operation code 03h). When the host wants to send the packet command to the optical storage device, the host will firstly send the task file register FIS with the command register value of A0H to the optical storage device. So, after the optical storage device receives the command register value of A0H, it knows that there are subsequent 12 bytes of ATAPI packet command. The first byte is the command mode, and the subsequent 11 bytes are the supplement data. When the first byte is 03H, it represents that the command is a request sense command. So, whether there is a request sense command can be detected by recognizing whether the first byte of the ATAPI packet command is 03H. If there is not a request sense command, the process jumps to step S512; or otherwise the process jumps to step S514. Step S512 is to set the sense key of the task file register FIS to 0BH and then the process jumps to step S516. FIG. 7 is a schematic illustration showing definitions of each bit in an ATAPI error register, wherein D4 to D7 are the sense keys. There is a conventional way for the parallel ATA device to deal with the noise interference during the DMA mode data transmission. When the CRC has errors, the device will set the sense key to 04H to inform the host. While an exception exists, when the executing command is the request sense command, the sense key is set to 0BH. The detail definition of the sense key may be found in the associated ATAPI specification. Step S514 is to set the sense key of the task file register FIS to 04H and then the process jumps to step S516. Step S516 is to set the check bit of the status register to 1 and set the ABRT bit of the error register to 1. FIG. 8 shows definitions of each bit in an ATAPI status register. As shown in FIG. 8, the bit 0 of the status register is the CHECK bit. As shown in FIG. 7, the bit 2 of the error register is the ABRT bit. When the check bit of the status register is 1, it indicates that an error occurred during execution of the previous command. The bits in the Error Register contain the Sense Key and Code. When the ABRT bit of the error register is 1, it indicates command aborted. Step S518 is to send back the task file register FIS from the device to the host, and then the process jumps back to step S502. Therefore, the method of the invention utilizes the ATA/ATAPI error feedback mechanism to process the noise interference according to the above-mentioned steps. Because the ABRT bit of the error register is set to 1 when the data FIS encounters the noise interference, the device requests the other side to resent whole FIS so as to effectively eliminate the problem of system halt caused by the noise interference when the data FIS is being sent. The method of FIG. 5 is used in the accessing device that directly receives the SATA interface signal. The invention additionally proposes a method of bridge solution to connect the data accessing device of the parallel ATA interface to the SATA interface, wherein the accessing device itself only receives the parallel ATA interface data. FIG. 9 is a flow chart showing a method of the invention for processing noise interference in a bridge solution. The bridge solution is disposed between the serial ATA interface and the parallel ATA interface of a data accessing device (e.g., an optical storage device). The flow chart is an advanced implementation when the link layer detects a CRC error or receives the receive-error primitive. The method of the invention for processing the noise interference in the bridge solution will be described with reference to FIG. 9. Step S902 is to detect whether the link layer has any error. The error state includes the CRC error, the receiving of the R_ERR primitive, or the receiving of the improper error primitive. If the link layer has not detected any error, step S902 is repeated. If the link layer has detected an error, the process jumps to step S904. Step S904 is to judge whether the FIS is a data type FIS. As shown in FIGS. 3 and 4, the first byte of each FIS is used to indicate the FIS type. That is, if the first byte is 27H, it represents that the FIS is a task file register FIS, and the process jumps back to step S902; and if the first byte is 46H, it represents that the FIS is a data type FIS, and the process jumps to step S906. Step S906 is to judge whether there is a command descriptor block CDB. When the host wants to send the packet command to the optical storage device, the host will firstly send the task file register FIS with the command register value of A0H to the optical storage device. So, after the optical storage device receives the command register value of A0H, it knows there are subsequent 12 bytes of ATAPI packet command. The first byte is the command mode and the subsequent 11 bytes are the supplement data. If there is a CDB, the process jumps to step S908. If there is not a CDB, the process jumps to step S910. Step S908 is to set a special mark in the CDB and then the process jumps back to step S902. For example, FFH is written into the CDB. Step S910 is to detect whether the data length is correct. If the data length is correct, the process jumps to step S914. Otherwise, the process jumps to step S912. Step S912 is to adjust the data length to correct data length and then the process jumps to step S914. For example, if the data length is not enough, the insufficient data is added; and if the data length is too long, the redundant data is discarded. Step S914 is to judge whether there is a DMA mode data transfer. As shown in FIG. 6, the bit 0 (D0) is the DMA mode. Thus, whether the DMA mode data transfer exists may be judged by only checking the data of bit 0 of the feature register. The definitions and functions of other bits may be found in the ATAPI specification. If there is not a DMA mode data transfer, the process jumps to step S902. Otherwise the process jumps to step S916. Step S916 is to generate an error CRC code at the parallel ATA interface, and then the process jumps back to step S902. Thus, the existing accessing device with the parallel ATA interface may be serially connected to the bridge solution, and the control method of FIG. 9 may be adopted. The accessing device with the parallel ATA interface can be connected to the SATA interface via the bridge solution and error information is added to the parallel ATA interface when the data FIS encounters the noise interference such that the device could request the data to be to resent. Thus, the problem of system halt caused by the noise interference when the data type FIS is being sent may be effectively solved. In summary, the method of the invention for processing noise interference in the bridge solution includes the following steps. 1. When the bridge solution receives the ATAPI CDB data packet (Data FIS) with noise interference, it sends the CDB with a special mark to the parallel ATA end, as shown in step S908, for example. This special mark is defined as abnormal ATAPI CDB type, so the device sends back the error state such that the computer resends this data packet (Data FIS). 2. When some primitives are mistaken as data bits because the data FIS encounters the noise interference, only the desired number of data sets to be sent is outputted to the device, as shown in steps S910 and S912, for example. 3. When the data is sent in the DMA mode and the data FIS encounters the interference because the SATA signal line has noises, the erroneous CRC is outputted to the device at the parallel ATA end. Thus, the host is enabled to resend the original command and information according to the error state response of the device, as shown in steps S914 and S916, for example. While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific construction and arrangement shown and described, since various other modifications may occur to those ordinarily skilled in the art. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The invention relates to a method for processing noise interference, and more particularly to a method for processing noise interference according to an error feedback mechanism of an ATA/ATAPI (AT Attachment with Packet Interface). 2. Description of the Related Art The serial ATA (Serial Advanced Technology Attachment, hereinafter referred to as SATA) is an interface specification commonly promoted by the companies of APT, Dell, IBM, Intel, Maxtor, Seagate, etc. The SATA specification is applied to the transmission interface of a hard disk drive or an optical disk drive to replace parallel ATA/ATAPI interface that has been used for a long time. The SATA interface specification specifies two pairs of differential signal lines to replace the original 40 or 80 signal lines connected in parallel. Serializing the original data can reduce the size and voltage and increase the speed. The specification also introduces some new functions, such as flow control and error resending, to control the data stream in a simple way. FIG. 1 is a schematic illustration showing communication layers in the SATA specification. As shown in FIG. 1 , the SATA interface connects a host 11 to a device 12 . The device 12 may be an optical storage device or a hard disk drive, or other devices with the SATA interface. The communication layers in the SATA specification include four layers, which are respectively a first layer (physical layer), a second layer (link layer), a third layer (transport layer) and a fourth layer (application layer). The physical layer is responsible for converting digital and analog signals. That is, the physical layer receives and converts a digital signal sent from the link layer into an analog signal and sends the analog signal to the other end. The physical layer also receives and converts the analog signal, which comes from the other end, into a digital signal and outputs the digital signal to the link layer. The link layer encodes and decodes the digital data. That is, the link layer encodes the data coming from the transport layer and outputs the encoded data to the physical layer. On the other hand, the link layer decodes the data coming from the physical layer and outputs the decoded data to the transport layer. The transport layer constructs and deconstructs the FIS (Frame Information Structure). The detailed definition of the FIS can be found in the SATA specification. The application layer is in charge of buffer memory and DMA engine(s). During the serializing process, the sending device converts the parallel data (e.g., data in bytes or words) into a serial bit data stream. In addition to the typical data, the SATA specification defines some data control codes with four bytes, which are referred to as primitives, for controlling the sending and power management of the sending device and the receiving device. For example, a X_RDY primitive (transmission data ready primitive) represents that the sending device is ready to send data, and a R_RDY primitive (receiver ready primitive) represents that the receiving device is ready to receive data. FIG. 2 is a schematic illustration showing a packet sent through the SATA interface. Two devices communicate with each other to send the packet according to the X_RDY primitive (transmission data ready primitive) and the R_RDY primitive (receiver ready primitive). Then, the sending side sends a packet content, which is packed by a SOF primitive (start of frame) and an EOF primitive (End of frame). After the packet content is sent completely, the sending side sends a WTRM primitive (wait for frame termination primitive). If there is no any error about the CRC (Cyclic Redundancy Check) check in the link layer, the receiving side responds with a R_OK primitive (reception with no error primitive) after it receives the WTRM primitive. If there is an error about the CRC check, the receiving side responds with a R_ERR primitive (reception error). The FIS is for transferring the task file register and data. Two examples will be described in the following. FIG. 3 is a schematic illustration showing a task file register FIS from a host to a device. That is, a task file register written from the host to the device is shown in FIG. 3 . FIG. 4 is a schematic illustration showing a data FIS from the host to the device or from the device to the host. That is, the data sent from the host to the device or from the device to the host is shown in FIG. 4 . In order to prevent the error caused by noises, the SATA specification specifies a resending mechanism. Almost all type of FISs (e.g., Register-Host to Device FIS or Set Device Bits-Device to Host FIS) are resent when a R_ERR primitive was received so as to ensure that the receiving device can receive the correct control information. However, the data FIS does not have this protection mechanism. When the data error occurs, the device cannot be protected by the resending mechanism under the condition of noise interference because the data FIS is not resent. Thus, the error data may be received. In a more serious condition, some portions of primitives may be mistaken as data bits, thereby making the number of data sets to be sent to the device greater than it should be. In some cases, this error may halt the system. In addition, in the device (e.g., an optical storage device) using the data FIS to send the ATA/ATAPI CDB (Command Descriptor Block), the CDB cannot be protected according to the resending mechanism because the data FIS is not resent. Thus, the device receives an abnormal control command, which causes a larger influence than in the case of sending the normal data using the data FIS. | <SOH> SUMMARY OF THE INVENTION <EOH>It is therefore an object of the invention to provide a method for processing noise interference in order to prevent the system from being stopped when the data FIS is interfered by noises. To achieve the above-mentioned object, the invention provides a method for processing noise interference. The method includes the steps of detecting error states by detecting whether a CRC (Cyclic Redundancy Check) code exists error or whether an error primitive is received, detecting whether a FIS (Frame Information Structure) is a data format if there is an error state and returning back to error state detecting step if the FIS is not a data format, detecting whether the FIS is a CDB (Command Descriptor Block) when the FIS is a data format, and modifying contents of the CDB, and writing a special mark to the CDB and returning back to the error state detecting step when the FIS is not a CDB. The method of the invention further comprises the steps of: detecting whether a data length of the FIS is correct when the FIS is not the CDB; adjusting the data length by increasing or decreasing data of the FIS so as to make the data length of the FIS correct when the data length of the FIS is incorrect; and generating an error CRC code and jumping back to the error state detecting step. | 20050124 | 20080311 | 20051027 | 98994.0 | 1 | TORRES, JOSEPH D | METHOD FOR PROCESSING NOISE INTERFERENCE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,040,030 | ACCEPTED | Semiconductor integrated circuit device | The present invention provides a semiconductor integrated circuit device equipped with a memory circuit, which realizes speeding up of its operation in a simple configuration or realizes high reliability and enhancement of product yields in a simple configuration. A memory cell is selected from within a memory array having a plurality of memory cells by a selector or selection circuit. MOSFETs constituting a precharge circuit provided for signal lines for transferring a read signal therefrom to a main amplifier are respectively brought to an on state based on a memory cell select start signal transferred to the selection circuit and brought to an off state prior to the transfer of the read signal from the memory cell to thereby complete precharging, whereby NBTI degradation at standby is avoided. | 1. A semiconductor integrated circuit device comprising: a word line; a first bit line; a memory cell arranged at intersection between the word line and the bit line; a column selection switch coupled to the bit line; a signal line pair coupled to the column selection switch; and a precharge circuit including a P-type first MOSFET whose source or drain is coupled to the signal line pair and whose gate is coupled to a precharge signal line, wherein a potential supplied to the precharge signal line changes a first potential to a second potential smaller than the first potential based on the change in RAS signal. 2. A semiconductor integrated circuit device according to claim 1, wherein the potential supplied to the precharge signal line changes the second potential to the first potential based on the change in CAS signal. 3. A semiconductor integrated circuit device according to claim 1, further comprising: wherein the source and drain of the first MOSFET are coupled between one of the signal line pair and the first potential, wherein the precharge circuit includes a P-type second MOSFET whose source and drain are coupled the other of the signal line pair and the first potential and a P-type third MOSFET whose source and drain are coupled between the signal line pair, and wherein gates of the second and third MOSFET are coupled to the precharge signal line. 4. A semiconductor integrated circuit device according to claim 1, further comprising: a bit line pair including the first bit line and a second bit line, a fourth MOSFET source and drain of the fourth MOSFET being coupled between the column selection switch and one of the signal line pair; and a fifth MOSFET source and drain of the fifth MOSFET being coupled between the column selection switch and the other of the signal line pair; and wherein a gate of the fourth MOSFET is coupled to the first bit line and a gate of the fifth MOSFET is coupled to the second bit line. 5. A semiconductor integrated circuit device according to claim 4, wherein the bit line pair is supplied the third potential between the first and second potential in standby term of the semiconductor integrated circuit. 6. A semiconductor integrated circuit device according to claim 1, wherein in a first term, the signal line pair is supplied the first potential and the precharge signal line is supplied the second potential, and wherein in a second term, the signal line pair is supplied the second potential and the precharge signal line is supplied the first potential. 7. A semiconductor integrated circuit device according to claim 6, further comprising: a sixth MOSFET, one of the source and drain being coupled to one of the signal line pair, and a seventh MOSFET, one of the source and drain being coupled to the other of the signal line pair, wherein in the first term, the signal line pair is supplied the second potential via the six and seventh MOSFETs. | BACKGROUND OF THE INVENTION The present invention relates to a semiconductor integrated circuit device, and to a technology effective for application to a device equipped with a memory circuit. It has been reported that according to the known prior art search subsequent to the completion of the invention of the present application, Unexamined Patent Publication No. Hei 10(1998)-21686 (hereinafter called “a patent document 1”) and Unexamined Patent Publication No. Hei 7(1995)-37387 (hereinafter called “a patent document 2”) have been disclosed as ones wherein precharge circuits are respectively provided for signals lines for transferring read signals from memory cells as in the invention of the present application. Disclosed in the patent document 1 is that a memory circuit using capacity is provided for signals lines to properly perform a stage division of pipelines in a synchronous dynamic RAM (Random Access Memory), and a signal corresponding to an intermediate potential necessary for an amplifying operation of a main amplifier is stored in such a memory circuit to thereby provide a high-speed signal voltage. The patent document 2 discloses a circuit for supplying two types of write and read precharge voltages to signal lines according to operation modes. As a laid-open document example related to a degradation phenomenon of a MOS device due to the bias of each gate and temperature, which is called NBTI (Negative Bias Temperature Instability), there has been known IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 46, NO. 5, pp. 921-926, MAY, 1999. While the precharge circuit exists in the patent documents 1 and 2, no attention is paid to the NBTI. SUMMARY OF THE INVENTION The inventors of the present application have taken note of the fact that in a memory circuit of a dynamic RAM or the like, P channel MOSFETs for precharging IO lines for transferring read signals are brought to an on state upon standby free of execution of both reading and writing and placed under a bias condition in which they are most subject to the NBTI degradation. When a threshold voltage Vth of each precharge MOSFET referred to above increases due to the NBTI degradation, the time necessary for the precharge becomes long correspondingly. In the synchronous DRAM, for example, when a column address strobe signal CASN is asserted low in level as shown in a waveform diagram of FIG. 11, a precharge signal IOPR is brought to a high level and the precharge of read IO lines RIOT/RIOB is completed. Thereafter, a column select signal YS is raised to thereby read a signal amount with amplification polarity of each bit line, which has been amplified by a sense amplifier SA, into the post-precharge read IO lines RIOT/RIOB. When the amplification of a main amplifier MA is completed, the precharge signal IOPR is rendered low in level again in preparation with the following read cycle to precharge the IO lines RIOT/RIOB. Since a standby period, which takes up most of the time upon an actual use, is held in a state in which the IO lines RIOT/RIOB have been precharged, the precharge MOSFETs are under a bias state in which NBTI degradation with a gate voltage (Vgs) being negative, proceeds. Thus, the precharge time becomes long due to the degradation of the precharge MOSFETs, thereby inhibiting the speeding up of a CAS cycle. Namely, no problem occurs in the initial or first cycle for executing transition to a memory access from the standby period. There may, however, be cases in which in a burst mode for continuously performing reading in synchronism with the column address strobe signal CASN, a precharge period is extended as indicated by dotted lines due to the NBTI degradation, and a signal corresponding to the next address from the sense amplifier is outputted before the completion of precharging, in other words, in a state in which part of the signal amount is being left behind, thereby causing a malfunction due to mixing with such a signal. In order to avoid such a malfunction, there is a need to set a time margin having taken into consideration the extension of the precharge time due to the NBTI degradation and thereby set a burst mode. Namely, a problem arises in that there is a need to make a clock cycle of a clock CLKN longer by the time margin, so that the memory circuit is made slow in operating speed. In other respects, product yields are reduced because the memory circuit with no time margin is regarded as faulty. An object of the present invention is to provide a semiconductor integrated circuit device provided with a memory circuit, which realizes the speeding up of its operation in a simple configuration. Another object of the present invention is to provide a semiconductor integrated circuit device equipped with a memory circuit, which realizes high reliability and enhancement of product yields in a simple configuration. The above, other objects, and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings. A summary of a representative one of the inventions disclosed in the present application will be described in brief as follows: A memory cell is selected from within a memory array having a plurality of memory cells by a selector or selection circuit. MOSFETs constituting a precharge circuit provided for signal lines used for transferring a read signal therefrom to a main amplifier are respectively brought to an on state based on a memory cell select start signal transferred to the selection circuit and brought to an off state prior to the transfer of the read signal from the memory cell to thereby complete precharging, whereby NBTI degradation at standby is avoided. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram showing one embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof; FIG. 2 is a timing diagram for describing one example of the operation of the dynamic RAM shown in FIG. 1; FIG. 3 is a circuit diagram illustrating one embodiment of a timing generator for forming a precharge signal IOPR shown in FIG. 2; FIG. 4 is an overall configuration diagram showing one embodiment of a read system circuit in a dynamic RAM according to the present invention; FIG. 5 is a circuit diagram illustrating another embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof; FIG. 6 is a timing diagram for describing one example of the operation of the dynamic RAM shown in FIG. 5; FIG. 7 is a circuit diagram showing a further embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof; FIG. 8 is a timing diagram for describing one example of the operation of the dynamic RAM shown in FIG. 7; FIG. 9 is a timing diagram for describing another example of the operation of the dynamic RAM according to the present invention; FIG. 10 is a timing diagram for describing a further example of the operation of the dynamic RAM according to the present invention; and FIG. 11 is a waveform diagram for describing the operation of a synchronous DRAM discussed by the inventors of the present application prior to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will hereinafter be described in detail with reference to the accompanying drawings. FIG. 1 is a circuit diagram of one embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof. A memory cell unit is typically shown which comprises one word line WL, a pair of bit lines BLT and BLB extending in parallel, and a dynamic memory cell MC provided at an intersecting point of the word line WL and one bit line BLB, all of which are illustratively shown as representatives. The dynamic memory cell MC has a gate connected to the word line WL and drain-source paths whose one is connected to the bit line BLB, and comprises a memory capacitor having a storage node to which the other thereof is connected. The symbol BL indicates a bit line. T added to the end thereof means the true (non-inversion) of a logic symbol and B means the bar (inversion). This T/B is used even in RIO indicative of each read signal line to be described later as in the case of RIOT/RIOB. Further, N added to each signal to be described later means negative and is indicative of being active (negative logic) when low in level. In the drawings, ◯ marks each indicative of “inversion”, which are added to the gates, means P channel MOSFETs. The P channel MOSFETs are distinguished from N channel MOSFETs by the marks. A sense amplifier unit comprises a sense amplifier SA constituent of a CMOS latch circuit represented by a black box in the same drawing, and a read amplifier RA. The read amplifier RA comprises column selecting MOSFETs Q1 and Q3, and amplifying MOSFETs Q2 and Q4. The gates of the MOSFETs Q1 and Q3 used as the column selection switches are switch-controlled by a column select signal YS so that a pair of amplified signals of the sense amplifier SA, i.e., amplified signals on the complementary bit lines BLB and BLT of the memory cell unit are transferred to their corresponding gates of the amplifying MOSFETs Q2 and Q4. A series circuit of the MOSFETs Q1 and Q2, and Q3 and Q4 constituting the read amplifier RA is provided between the pair of read signal lines RIOT/RIOB and a circuit's ground potential. One of the read signal lines RIOT/RIOB is discharged in response to the corresponding amplified signal of the sense amplifier SA to thereby perform an amplifying operation. In order to perform the amplifying operation by such a read amplifier RA as described above, a precharge circuit is provided for the read signal lines RIOT/RIOB. The precharge circuit comprises a P channel MOSFET Q5 for short-circuiting the read signal lines RIOT/RIOB, and P channel MOSFETs Q6 and Q7 for supplying a precharge voltage VDD to the signal lines RIOT/RIOB respectively. Before the amplifying operation by the read amplifier RA, the precharge circuit precharges the read signal lines RIOT/RIOB to a power supply voltage VDD and discharges one of the signal lines to the circuit's ground potential (low level) according to the amplifying operation of the read amplifier RA to thereby form amplifying signals necessary for an amplifying operation of the main amplifier MA. Although not restricted in particular, the precharge circuit is provided in the main amplifier unit. Namely, an input unit of the main amplifier MA comprised of a differential amplifier circuit is provided with the MOSFETs Q5 through Q7 constituting the precharge circuit. When the main amplifier MA starts its amplifying operation, it sets differential inputs to equal precharge voltages. A timing diagram for describing one example of the operation of the dynamic RAM shown in FIG. 1 is shown in FIG. 2. Although not restricted in particular, the dynamic RAM according to the present embodiment is intended for a DRAM operated in synchronization with a clock CLKN. Alternatively, the clock CLK may adopt a clock signal, i.e., a system clock signal of a memory control circuit for generating the respective signals RASN, CASN, WEN, etc. without being directly supplied to the dynamic RAM. In the present embodiment, a precharge signal IOPR is brought to a high level when a row address strobe signal RASN is in a standby state indicative of a high level. Thus, the P channel MOSFETs Q5 through Q7 constituting the precharge circuit are respectively brought to an off state. The read signal lines RIOT/RIOB are respectively brought to a floating state with the off states of the MOSFETs Q5 through Q7 and hence their levels are undefined. In synchronization with the edge at which the clock signal CLKN falls to a low level, the row address strobe signal RASN is rendered low in level so that a row address signal is taken in or captured to start a row selective operation. With a change of the signal RASN to the low level, the precharge signal IOPR is taken low in level so that the P channel MOSFETs Q5 through. Q7 are respectively brought to an on state. As a result, the read signal lines RIOT/RIOB are supplied with the precharge voltage like the power supply voltage VDD. With the row selective operation, the word line WL is raised so that one of the bit lines BLT and BLB is brought to a voltage corresponding to an electrical charge stored in the corresponding memory cell, and the other thereof maintains the precharge voltage. Therefore, a small amount of signal corresponding to the difference between the voltage and the precharge voltage is amplified by the sense amplifier SA comprised of the CMOS latch circuit, and a small difference in potential between the bit lines BLT and BLB is expanded to a high level/low level corresponding to an operating voltage of the sense amplifier SA, so that a rewrite (refresh) operation is effected on a memory capacitor of a selected memory cell. In consideration of the row selective operation referred to above, a column address strobe signal CASN is taken low in level in synchronism with, for example, a third cycle of the clock signal CLKN as viewed from the falling edge of the RASN so that capturing of a column address and its decode operation are started. In response to a change of the CASN to the low level, the precharge signal IOPR is taken high in level so that a precharge operation is completed. In response to the completion of the precharge operation, one column select signal YS is brought to a high level by the decode operation, so that one of the read signal lines RIOT/RIOB is discharged by the read amplifier RA. The discharged signal is amplified by the main amplifier MA, after which it is outputted through an unillustrated output circuit. In a burst mode (or page mode) for performing switching between continuous column addresses, the column select signal YS is reset to a low level in response to the completion of the amplifying operation of the main amplifier MA so that the precharge signal IOPR is taken low in level. Thus, the read signal lines RIOT/RIOB are precharged to the power supply voltage VDD in preparation for the next read operation to equalize the read signals. When the CASN is taken low in level again in synchronism with the clock signal CLKN, the capturing of a column address or the updating thereof by a counter is carried out. In response to the change of the CASN to the low level, the precharge signal IOPR is brought to the high level again to complete the precharge operation. The column select signal YS corresponding to the updated column address is taken high in level according to the completion of the precharge operation, so that read signals on the bit lines BLT/BLB, corresponding to it are transferred onto the read signal lines RIOT/RIOB via the read amplifier RA. Thus, one of the read signal lines RIOT/RIOB is discharged and thereafter the discharged signal is amplified by the main amplifier MA, followed by its output via the unillustrated output circuit. In order to speed up the read cycle (CAS cycle) of the column system as described above, the time required to read the amounts of signals into the read signal lines RIOT/RIOB and the time required to precharge the read signal lines RIOT/RIOB must be made fast or speeded up. The precharge time is determined by a load on the read signal lines RIOT/RIOB and a current driving force of the precharge MOSFETs Q5 through Q7. It must be designed to assume the optimum value due to the fact that even though the current driving force increases if gate widths W of the precharge MOSFETs Q5 through Q7 are made great, a layout area increases, the signal lines RIOT/RIOB increase in parasitic capacitance, and the coupling between the precharge signal IOPR and the read signal lines RIOT/RIOB is made high, for example. On the other hand, the characteristics of devices for the precharge MOSFETs Q5 through Q7 involve a degradation phenomenon (NBTI) that holes are injected into a gate oxide film when the bias of each gate to the source/drain is negative, so that a threshold voltage Vth is shifted (raised) and the conductance of each of the MOSFETs Q5 through Q7 is reduced. Hence there is a need to carry out device design with a target standard of ΔVth=20 mV/10 years, for example. Namely, there is a need to perform design having a timing margin so as to withstand a ΔVth shift of 20 mV upon design of a memory circuit. Since much time necessary for an actual operation of the dynamic RAM at the time that the dynamic RAM is mounted on a system, is held in a standby state, and the signal lines RIOT/RIOB are held in a state of being precharged by the precharge MOSFETs Q5 through Q7, the gates thereof that produce NBTI degradation, are kept in a negative bias state (−VDD), and hence the CAS cycle must be designed inclusive of a sufficient timing margin. In the dynamic RAM, however, there has been an increasingly demand for speeding up of the CAS cycle for the purpose of speeding up its operation. The timing margin is becoming unallowable. Therefore, the present invention intends to control the precharge signal IOPR to such a bias condition that the NBTI degradation is not developed in the standby state taking up the actual operation in excess as shown in the timing diagram of FIG. 2 to thereby make a timing margin corresponding to the NBTI degradation unnecessary and speed up the CAS cycle, thus enhancing the performance of the system. Since, in the present embodiment, the precharge of the read signal lines RIOT/RIOB is stopped and the precharge signal is controlled to such a bias state as not to develop the NBTI degradation during a standby period in which the row address strobe signal RASN is high in level, the NBTI degradation in actual use is not almost produced and the precharge time is degraded either, thereby making it possible to speedup-design the CAS cycle. Namely, a bias voltage Vgs of each gate relative to the source/drain becomes 0V as shown in the timing diagram of FIG. 2, thus resulting in an NBTI degradation-free state. A circuit diagram of one embodiment of a timing generator for forming the precharge signal IOPR is shown in FIG. 3. In the same drawing, CLKN indicates the basic clock, RASN indicates a row control (row address strobe) signal, CASN indicates a column control (column address strobe) signal, and RSETN indicates an initialization (reset) signal, respectively. The present circuit comprises flip-flops FFs, inverters INV1 through INV3, gates G1 through G5, and delays Delays. An internal RAS is produced by delaying the negate side of the row address strobe signal RASN and thereby expanding its pulse width. An internal CAS is produced based on one shot pulse having a width determined by an internal delay in response to the assertion of the column address strobe signal CASN. In the present embodiment, a NAND gate G5 receiving therein the internal RAS during a so-called standby period in which the row address strobe signal RASN and column address strobe signal CASN both taking up a major part of time in an actual use state are also high in level, is added to thereby configure logic such that the precharge signal IOPR is negated. Thus, the standby period in which the row address strobe signal RASN is high in level, makes it possible to stop the precharge of the read signal lines RIOT/RIOB and bring about a bias state in which no NBTI degradation occurs in the precharge MOSFETs Q5 through Q7. An overall configuration diagram of one embodiment of a read system circuit in a dynamic RAM according to the present invention is shown in FIG. 4. An internal RAS generator RASG forms or produces an internal RAS according to a row address strobe signal RASN in response to the row address strobe signal RASN. This internal RAS signal is transferred to an X address latch and comparator XACP, an X predecoder XPDEC, and a precharge signal generator IOPRG. The X address latch and comparator XACP performs the capturing of a row address and a defective address comparison. The X predecoder XPDEC supplies a signal obtained by predecoding the address to array controllers ACs of memory mats. Each of the array controllers ACs forms a select signal for each word line, activates the word line through a word driver WD, and controls the startup of a sense amplifier SA, operating timings provided to precharge bit lines BLT and BLB and the lowering of each word line. When the address latch and comparator XACP now detects that a failure occurs in a normal word line, the operation of selecting each normal word line of the corresponding normal mat is stopped and a redundant word line of a redundant mat is selected as an alternative to it. According to such word-line switching, the sense amplifier SA of the normal mat is deactivated and the sense amplifier SA of the corresponding redundant mat is activated. In response to a column address strobe signal CASN, an internal CAS generator CASG forms an internal CAS according to it. This internal CAS signal is transferred to a Y address latch and comparator YACP, a Y predecoder YPDEC, and the precharge signal generator IOPRG. The Y address latch and comparator YACP performs the capturing of a column address and a defective address comparison. The Y predecoder YPDEC supplies a signal obtained by predecoding the address to column selectors or selection circuits of the memory mats. Thus, an address for each activated column select signal YS is latched according to the internal CAS generated from the column address strobe signal CASN, whereby the activation of the column select signal, the startup of a main amplifier MA and timing provided to precharge signal lines RIOT/RIOB are controlled. In the present invention, the internal RAS is also added to perform the control on the precharge timing for the signal lines RIOT/RIOB. Thus, such a bias state that no NBTI degradation occurs in the precharge MOSFETs Q5 through Q7 during the standby period, can be brought about. Data amplified by the main amplifier MA is outputted through an output circuit DOB as a read signal DOUT. The output circuit DOB is provided with a latch FF. Although not restricted in particular, the DRAM according to the present embodiment is provided with a write path or route separately from the read path. A write signal DIN is inputted through an input circuit DIB and transferred to a write buffer WB. The write buffer WB drives each write signal line WIO and thereby transfers the write signal to bit lines BLT and BLB selected by the corresponding column select signal YS. Consequently, the corresponding word line is selected and thereby an electrical charge corresponding to the write signal is written into its corresponding memory capacitor of a memory cell connected to the bit line BLT or BLB to which the write signal is transferred. A circuit diagram of another embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof is shown in FIG. 5. The present embodiment is basically similar to the embodiment of FIG. 1 but performs such a contrivance as to recover NBTI degradation developed in an active period (precharge operation period) as well as to suppress the NBTI degradation in the precharge-MOSFETs Q5 through Q7 as in the embodiment shown in FIG. 1. The NBTI degradation in the MOSFETs has such a characteristic that when biases applied between a gate and a source and drain are made positive in reverse, the degradation is recovered. Using such a characteristic, N channel MOSFETs Q8 and Q9 are added to change a precharge voltage VIOR supplied to MOSFETs Q6 and Q7 to a ground potential VSS (0V) upon standby. The changed precharge voltage VIOR (VSS) is transferred to its corresponding read signal lines RIOT/RIOB through the added MOSFETs Q8 and Q9. Being supplied with a row timing signal R3B controls the gates of the MOSFETs Q8 and Q9. A timing diagram for describing one example of the operation of the dynamic RAM of FIG. 5 is shown in FIG. 6. While the present timing diagram is basically similar to the timing diagram of FIG. 2, the signal R3B is brought to a high level during a standby period to thereby bring the MOSFETs Q8 and Q9 into an on state. Thus, the read signal lines RIOT/RIOB are fixed to the circuit's ground potential VSS without being fixed to such a floating state as shown in FIG. 2. The precharge voltage VIOR is also switched to the ground potential VSS. Thus, the gates of the P channel MOSFETs Q5 through Q7 are fixed to a high level like a power supply voltage VDD similarly to FIG. 2, and their sources and drains are respectively set to the low levels (VSS) of the signal lines ROT/RIOB and precharge voltage VIOR, so that a voltage Vgs between each gate and its corresponding source/drain is set to a positive voltage like VDD. Thus, NBTI degradation developed in the MOSFETs Q5 through Q7 is recovered. Incidentally, a precharge signal IOPR is set to VSS in response to a signal RASN during a precharge period in a manner similar to the embodiment of FIG. 2 to bring the precharge MOSFETs Q5 through Q7 to an on state, so that the precharge voltage VIOR is switched to the power supply voltage VDD to precharge the signal lines RIOT/RIOB to the power supply voltage VDD. At this time, the MOSFETs Q8 and Q9 are in an off state according to a low level of the signal R3B. A circuit diagram showing a further embodiment of a read system from a sense amplifier SA of a dynamic RAM mounted in a semiconductor integrated circuit device according to the present invention to a main amplifier MA thereof is shown in FIG. 7. The present embodiment is an improved one of the embodiment shown in FIG. 5. The present embodiment is one in which such a contrivance as to realize the function of recovering NBTI degradation produced during an active period (precharge operation period) in a manner similar to the embodiment of FIG. 5 without the addition of the MOSFETs Q8 and Q9 is performed. Namely, MOSFETs Q1 through Q4 of a read amplifier RA are utilized to bring read signal lines RIOT/RIOB to a low level for the purpose of recovering the NBTI degradation, whereby the MOSFETs Q8 and Q9 are omitted. A timing diagram for describing one example of the operation of the dynamic RAM shown in FIG. 7 is shown in FIG. 8. The present timing diagram is basically similar to the timing diagram shown in FIG. 6. In the present timing diagram, however, any one column select signal YS is brought to a high level during a standby period, so that the MOSFETs Q1 and Q3 of any one read amplifier are brought to an on state. Upon the standby, a half precharge voltage is set to bit lines BLT and BLB corresponding to it so that the MOSFETs Q2 and Q4 are brought to an on state. Accordingly, the setting of any one column select signal YS to the high level during the standby period as described above makes it possible to pull the read signal lines RIOT/RIOB to a low level. Currents that flow through the MOSFETs Q2 and Q4 brought to the on state by the half precharge voltage, become small according to the voltage. Thus, even though the time required to pull the read signal lines to the low level becomes long as compared with the case where the MOSFETs Q8 and Q9 are provided for the read signal lines RIOT/RIOB, no problem occurs because the standby period per se is long. The read signal lines RIOT/RIOB are fixed to a circuit's ground potential VSS by use of the read amplifier RA in this way. A precharge voltage VIOR is also switched to the circuit ground potential VSS. Accordingly, the gates of P channel MOSFETs Q5 through Q7 are respectively fixed to a high level like a power supply voltage VDD in a manner similar to FIG. 2, and their sources and drains are respectively set to the low levels (VSS) of the signal lines ROT/RIOB and precharge voltage VIOR, so that a voltage Vgs between each gate and its corresponding source/drain is set to a positive voltage like VDD. Thus, NBTI degradation developed in the MOSFETs Q5 through Q7 is recovered. A timing diagram for describing another example of the operation of the dynamic RAM according to the present invention is shown in FIG. 9. A timing diagram of the read system circuit during a write cycle is illustrated in the same drawing. During the write cycle, write data is transferred to a memory cell selected through the write signal line WIO of FIG. 4. Since, at this time, the read signal lines RIOT/RIOB have been precharged, a bias relationship in which the NBTI degradation proceeds, is established even in the present invention. However, the standby period, which takes up a lot of actual operations, makes it possible to suppress the degradation because it is in bias relation in which no degradation proceeds, in a manner similar to the read cycle. The DRAM added with the NBTI degradation recovery function shown in each of the embodiments illustrated in FIGS. 5 and 7 makes it possible to recover the progress of NBTI degradation of the read signal lines ROT/RIOB developed during the write cycle. A timing diagram for describing a further example of the operation of the dynamic RAM according to the present invention is shown in FIG. 10. The present embodiment is intended for a synchronous DRAM (hereinafter called simply “SDRAM”). While the SDRAM is operated by being inputted with operation commands according to signals such as RASB, CASB, WEB, etc., internal operations thereof are the same as in the case where, for example, an ACTV (active) command is equivalent to the RASN assertion of FIG. 2 and a PRE (precharge) command is equivalent to the RASN negation of FIG. 2. Therefore, the present invention can be applied as it is. For instance, an unillustrated chip select signal CSB gives instructions for the start of a command input cycle according to its low level. A case in which the chip select signal CSB is high in level (in a chip non-selected state), and other inputs are meaningless. However, the state of selection of each memory bank to be described later, and internal operations such as a burst operation or the like are not affected by a change to the chip non-selected state. The respective signals of RASB, CASB and WEB are different in function from the corresponding signals (the RASN, CASN and WEN) employed in a normal DRAM and are defined as signals significant when a command cycle to be described later is defined. A clock enable signal CKE is a signal for instructing validity of the next clock signal. When the corresponding signal CKE is high in level, the rising edge of the next clock signal CLKN is made valid, whereas when the signal CKE is low in level, it is rendered invalid. Incidentally, when an external control signal OEB for effecting output enable control on a data output circuit is provided, such a signal OEB is also supplied to a control circuit. When the signal is high in level, for example, the data output circuit is brought to a high output impedance state. The row address signal is defined according to the level of an address signal in a row address strobe/bank active command cycle synchronized with the rising edge of the clock signal CLKN (internal clock signal). An upper-bit signal of the address signal is regarded as a bank select signal in the row address strobe/bank active command cycle. One of four memory banks 0 through 3 is selected by a combination of A12 and A13, for example. Control on the selection of each memory bank can be performed by processes such as the activation of only a row decoder on the selected memory bank side, all the non-selection of column switch circuits on the non-selected memory bank side, connections to a data input circuit and a data output circuit on the selected memory banks side alone, etc. A column address is taken in or captured by a READ (read) command to start a selecting operation of a column system. Therefore, the precharge operation of the read signal lines RIOT/RIOB is completed according to the input of the READ command to transmit read signals. Since the PRE (precharge) command corresponds to the RASN negation as described above and thereby enters a standby period, the precharge operation of the read signal lines RIOT/RIOB is completed to enter into a floating state. While a Rambus-spec DRAM is known as a memory using dynamic memory cells, even this DRAM is operated according to a command equivalent to ACTV/READ or the like given by a packet. Therefore, the present invention can be applied in a manner similar to the above SDRAM. In the invention of the present application described above, P channel MOSFETs for IO-line precharge are set to such a bias condition as to make it hard to cause NBTI degradation upon standby or as to recover the NBTI degradation, thereby making it possible to speed up a CAS cycle. Namely, since they are less subject to a time extension expended on precharge due to NBTI degradation, a circuit's high-speed operation can be assured. As a result, selective yields are enhanced because a semiconductor integrated circuit device can be shipped even if sorted on the verge of its specs. An aim at developing a device with the NBTI degradation is about 20 mV/10 years as described above. However, when the present circuit system is used, the shift amount of Vth can be set to an almost negligible level, and hence a circuit's high-speed operation can be assured. While the invention developed above by the present inventors has been described specifically based on the illustrated embodiments, the invention of the present application is not limited to the embodiments. It is needless to say that various changes can be made thereto within the scope not departing from the substance thereof. The sense amplifier SA can be regarded as a static memory cell in FIG. 1 and the like, for example. Namely, even when a static RAM is configured in such a manner that a plurality of memory cells comprising CMOS latch circuits each corresponding to a sense amplifier SA are connected to a memory cell unit and selected by their corresponding word lines, the present invention can similarly be applied. In such a case, precharge MOSFETs are controlled by a mat enable signal or chip enable signal CE in response to a RAS signal employed in a DRAM. In the embodiment shown in FIG. 4 and the like, the write signal line WIO may be configured as a common IO line used in common with the read signal line RIO. The present invention can be widely used in semiconductor integrated circuit devices each equipped with the above DRAM, SRAM, flash memory, and other general memory products. Advantageous effects obtained by a typical one of the inventions disclosed in the present application will be described in brief as follows: A memory cell is selected from within a memory array having a plurality of memory cells by a selector or selection circuit. MOSFETs constituting a precharge circuit provided for signal lines for transferring a read signal therefrom to a main amplifier are respectively brought to an on state based on a memory cell select start signal transferred to the selection circuit and brought to an off state prior to the transfer of the read signal from the memory cell to thereby complete precharging, whereby NBTI degradation at standby can be avoided. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to a semiconductor integrated circuit device, and to a technology effective for application to a device equipped with a memory circuit. It has been reported that according to the known prior art search subsequent to the completion of the invention of the present application, Unexamined Patent Publication No. Hei 10(1998)-21686 (hereinafter called “a patent document 1”) and Unexamined Patent Publication No. Hei 7(1995)-37387 (hereinafter called “a patent document 2”) have been disclosed as ones wherein precharge circuits are respectively provided for signals lines for transferring read signals from memory cells as in the invention of the present application. Disclosed in the patent document 1 is that a memory circuit using capacity is provided for signals lines to properly perform a stage division of pipelines in a synchronous dynamic RAM (Random Access Memory), and a signal corresponding to an intermediate potential necessary for an amplifying operation of a main amplifier is stored in such a memory circuit to thereby provide a high-speed signal voltage. The patent document 2 discloses a circuit for supplying two types of write and read precharge voltages to signal lines according to operation modes. As a laid-open document example related to a degradation phenomenon of a MOS device due to the bias of each gate and temperature, which is called NBTI (Negative Bias Temperature Instability), there has been known IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 46, NO. 5, pp. 921-926, MAY, 1999. While the precharge circuit exists in the patent documents 1 and 2, no attention is paid to the NBTI. | <SOH> SUMMARY OF THE INVENTION <EOH>The inventors of the present application have taken note of the fact that in a memory circuit of a dynamic RAM or the like, P channel MOSFETs for precharging IO lines for transferring read signals are brought to an on state upon standby free of execution of both reading and writing and placed under a bias condition in which they are most subject to the NBTI degradation. When a threshold voltage Vth of each precharge MOSFET referred to above increases due to the NBTI degradation, the time necessary for the precharge becomes long correspondingly. In the synchronous DRAM, for example, when a column address strobe signal CASN is asserted low in level as shown in a waveform diagram of FIG. 11 , a precharge signal IOPR is brought to a high level and the precharge of read IO lines RIOT/RIOB is completed. Thereafter, a column select signal YS is raised to thereby read a signal amount with amplification polarity of each bit line, which has been amplified by a sense amplifier SA, into the post-precharge read IO lines RIOT/RIOB. When the amplification of a main amplifier MA is completed, the precharge signal IOPR is rendered low in level again in preparation with the following read cycle to precharge the IO lines RIOT/RIOB. Since a standby period, which takes up most of the time upon an actual use, is held in a state in which the IO lines RIOT/RIOB have been precharged, the precharge MOSFETs are under a bias state in which NBTI degradation with a gate voltage (Vgs) being negative, proceeds. Thus, the precharge time becomes long due to the degradation of the precharge MOSFETs, thereby inhibiting the speeding up of a CAS cycle. Namely, no problem occurs in the initial or first cycle for executing transition to a memory access from the standby period. There may, however, be cases in which in a burst mode for continuously performing reading in synchronism with the column address strobe signal CASN, a precharge period is extended as indicated by dotted lines due to the NBTI degradation, and a signal corresponding to the next address from the sense amplifier is outputted before the completion of precharging, in other words, in a state in which part of the signal amount is being left behind, thereby causing a malfunction due to mixing with such a signal. In order to avoid such a malfunction, there is a need to set a time margin having taken into consideration the extension of the precharge time due to the NBTI degradation and thereby set a burst mode. Namely, a problem arises in that there is a need to make a clock cycle of a clock CLKN longer by the time margin, so that the memory circuit is made slow in operating speed. In other respects, product yields are reduced because the memory circuit with no time margin is regarded as faulty. An object of the present invention is to provide a semiconductor integrated circuit device provided with a memory circuit, which realizes the speeding up of its operation in a simple configuration. Another object of the present invention is to provide a semiconductor integrated circuit device equipped with a memory circuit, which realizes high reliability and enhancement of product yields in a simple configuration. The above, other objects, and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings. A summary of a representative one of the inventions disclosed in the present application will be described in brief as follows: A memory cell is selected from within a memory array having a plurality of memory cells by a selector or selection circuit. MOSFETs constituting a precharge circuit provided for signal lines used for transferring a read signal therefrom to a main amplifier are respectively brought to an on state based on a memory cell select start signal transferred to the selection circuit and brought to an off state prior to the transfer of the read signal from the memory cell to thereby complete precharging, whereby NBTI degradation at standby is avoided. | 20050124 | 20060404 | 20050728 | 59999.0 | 0 | NGUYEN, TAN | SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,040,037 | ACCEPTED | Facing for insulation and other applications | A method and material for covering exposed insulation surfaces to protect them from moisture and other environmental factors. The covering typically includes a first, exposed layer of a metal-containing foil, a second layer of a metal-containing foil, a layer of a polymer disposed between the first two layers of foil, a third layer of a metal-containing foil, and a second layer of polymer disposed between the second and third layers of foil. A layer of a pressure sensitive adhesive is applied to one of the exposed layers of foil, and the pressure sensitive adhesive layer is covered with a release liner prior to application. The foil provides the necessary moisture and weather seal while the polymer provides the necessary strength and puncture resistance. The overall thickness of the laminate typically is less than 100 microns, permitting it to be easily cut and manipulated at the job site while providing an effective, long lasting weather seal. | 1-16. (canceled) 17. A method for protecting insulation from damage due to moisture and other environmental factors, said method comprising: providing a covering material having a metal-containing layer on one surface and a layer of a pressure sensitive adhesive on a second, opposite surface, said covering material including at least one layer of a puncture resistant material disposed between the metal-containing layer and the adhesive layer; manually cutting from the covering material an appropriately sized first sheet at a job site; removing a release liner covering the pressure sensitive adhesive layer of the first sheet; applying the first sheet to the insulation so that the adhesive layer bonds to the insulation and the metal-containing layer is exposed; and applying additional sheets of covering material directly to the insulation such that each sheet of covering material overlaps sheets of covering material directly adjacent thereto. 18. The method as recited in claim 17 wherein said manually cutting step comprises cutting the covering material into sheets having shapes that conform to an external shape and size of the insulation being covered. 19. The method as recited in claim 17 further comprising, for a pipe having a curved portion, wrapping lengths of a pressure sensitive adhesive tape having a layer of a metal-containing foil and a layer of a puncture resistant polymer about the sheets of covering material to conform the covering material to the configuration of the pipe. 20. The method as recited in claim 17 further comprising sealing seams between adjacent sheets of covering material with a pressure sensitive adhesive tape. 21. The method as recited in claim 17 wherein the covering material is formed of a laminate of aluminum foil, and polyester in multiple, alternating layers. 22. The method as recited in claim 17 wherein for an insulated duct having a substantially rectangular cross-sectional shape, the first and second applying steps comprise: applying the first sheet of covering material to a bottom wall of the duct so that an overlapping portion of the sheet extends upwardly along each side wall of the insulated duct immediately adjoining the bottom wall; thereafter applying a cut sheet of covering material to each side wall of the insulated duct so that each sheet on the side wall overlaps the overlapping portion of the first sheet extending upwardly from the bottom wall and so that another overlapping portion of each sidewall sheet of material extends beyond the side wall and along the top wall of the insulated duct; and applying a fourth sheet of a covering material to the top wall of the duct to overlap the overlapping portions of the sheets of material on the side wall which extend along the top wall. 23-28. (canceled) | FIELD OF THE INVENTION This invention relates generally to insulation products for use with fluid conduits, such as pipes or ducts, and more particularly, to a facing material for use with insulation surrounding fluid conduits for providing a vapor barrier and a weather seal. BACKGROUND OF THE INVENTION Pipes or duct work in dwellings, commercial buildings and industrial plants are used for heating or air conditioning purposes and therefore carry fluids, such as heated or cooled air, or steam. In industrial applications, pipes or duct work also may carry chemicals or petroleum products or the like. Such pipes our duct work and associated heating or air conditioning units typically are covered with an exterior layer of insulation. The duct work typically is formed of aluminum or steel, while the pipes may be formed of any suitable material, such as copper, steel, aluminum, plastic, rubber or other like materials. The insulation used to cover such pipes or duct work and associated heating and air conditioning units often includes fiberglass or mineral wool, foamed cellular glass or a rigid foam, covered by a jacket of foil or a layer of paper, such as kraft paper. Other layers of materials may be included in the insulation jacket, such as a layer of foil, a scrim, or a layer of polyester. Duct board is often used to cover duct work. When such pipes or duct work are in a location exposed to weather or when they are in other environments where the exterior insulation surface is subject to degradation by moisture or the like, it is common to cover the insulation with a facing. This is particularly true for insulation having an exterior layer of paper or for duct board, (whether or not the surface is a metalized layer or a paper layer) to protect the insulation from moisture, sun, wind or other weather elements. In one existing example, sheet metal cladding is applied to the exterior surface of the insulation. Such cladding typically is formed of aluminum, stainless steel, galvanized steel, or another like metal. This cladding has certain drawbacks including the fact that such cladding is very expensive and time consuming to install. In addition, metal cladding is not water or vapor tight or weatherproof because of joints, any repairs can be quite costly, prefabrication of the cladding is required off site, and metal cladding is very heavy and therefore difficult to handle. Another existing solution is to cover the insulation with butyl rubber. However, this solution also has drawbacks including the fact that the butyl rubber does not perform well and tends to delaminate, particularly in extreme weather conditions. Butyl rubber also is very difficult to apply because it is messy to cut and form, and it is very heavy. Moreover, butyl rubber has been known to cause delamination of the outer surface of the insulation from the fiberglass or the wool disposed in the interior because of its weight and because of its lack of strength at elevated temperatures. A butyl rubber covering tends to have a poor appearance, and does not perform well at temperatures below zero degrees Fahrenheit or above 120° Fahrenheit and therefore should not be used in extreme weather environments where such exterior coverings are most desired and are often necessary. Butyl rubber also tends to creep, has a poor fire and smoke rating, and therefore is not UL listed. Finally, solvents are required to activate butyl rubber at temperatures below 45° F. It is also known to cover insulation with thin layers of aluminum foil using a butyl rubber adhesive. However, such coverings have little or no puncture resistance and the adhesive layer has the same drawbacks noted above, including a tendency to run or ooze at elevated temperatures. Scrim and mastics are also used to cover insulation. However, the use of such materials often is very labor intensive and requires a multiple step process. These products can only be applied during certain weather conditions, and it is very difficult to regulate the thickness of mastic to make it uniform. Consequently, such products have very limited applications, and generate a poor appearance. Another known product is bitumen felt and netting. This product is very labor intensive to apply and is not recommended for exterior use. It also has a very poor fire rating, and is unsightly. Thus, its use is very limited. In view of the foregoing, there exists a need for a material or facing for covering insulation, particularly exterior insulation, that is relatively inexpensive, easy to apply, provides a good appearance and provides the desired vapor and weather seal. There also is a need for a product which is fire resistant, has low maintenance costs and can be used in extreme temperature conditions. SUMMARY OF INVENTION This invention relates generally to a facing material for application to exposed surfaces of insulation or other like materials to provide a vapor seal and to protect the insulation from weather related damage. The facing of this invention overcomes the drawbacks of the prior art systems discussed above, since it is relatively inexpensive, is easy to apply, provides a good appearance, is easily cut and manipulated at the job site and provides a 100% vapor seal. The facing of this invention also can be applied and will maintain its integrity in extreme weather conditions and is very fire resistant. This invention also relates to a method for applying a facing to insulation. In one aspect, the invention includes a facing for insulation. One embodiment of the facing includes a first layer of a metal-containing foil, a second layer of a metal-containing foil, a third layer of a metal-containing foil, and a first layer of a puncture resistant polymer film disposed between the first and second layers of foil, and a second layer of a puncture resistant polymer film disposed between the second and third layers of foil. In another embodiment, a layer of pressure sensitive adhesive is applied to the third layer of foil. In yet another embodiment, at least the first layer of metal-containing foil may be formed of aluminum. In another embodiment, at least the first layer of the puncture resistant polymer film is formed of polyester. A typically thickness for the metal-containing foil layers is about 9 microns, while a typical thickness of the puncture resistant polymer film layers is about 23 microns or greater, although the polymer film layers could be as thin as 5 microns. In another aspect, a weather seal for use on exposed surfaces is disclosed. This weather seal includes a first layer of an aluminum foil, a second layer of a metal-containing foil, a third layer of a metal-containing foil, a first layer of a puncture resistant material disposed between the first layer of aluminum foil and the second layer of metal-containing foil, a second layer of a puncture resistant material disposed between the second and third layers of metal-containing foil and a layer of a pressure sensitive adhesive disposed on the third layer of metal-containing foil. In one embodiment, the first and second layers of puncture resistant material are formed of polyester. In another embodiment, the combined thickness of the weather seal is less than 100 microns. In another embodiment, the second and third layers of metal-containing foil are formed of a metalized foil. In another aspect, a covering for exterior and interior insulation is disclosed. This covering includes a first layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, a first layer of polyester adhered to the first layer of aluminum foil with an adhesive, the polyester layer having a thickness greater than about 23 microns, a second layer of aluminum foil adhered to the first layer of polyester material by an adhesive, the second layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, a second layer of polyester material adhered to the second layer of aluminum foil by an adhesive, the second layer of polyester material having a thickness greater than about 23 microns, a third layer of aluminum foil adhered to the second layer of polyester material by an adhesive, the third layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, and a pressure sensitive adhesive layer disposed on the third layer of aluminum foil. In yet another aspect of the invention, a covering for insulation is provided which includes multiple layers of a metal-containing foil and multiple layers of a puncture resistant, polymer film. The layers of puncture resistant polymer film are alternated with the layers of a metal-containing foil. The covering also includes a layer of a pressure sensitive adhesive disposed on one side of the covering, and on the other, exposed side of the covering, a layer of material resistant to ultraviolet radiation, acid rain, and salt. The covering is sufficiently flexible that it may be conformed to the shape of an insulated pipe. In another aspect, a method for protecting insulation from damage due to moisture and other environmental factors is disclosed. This method includes the step of providing a covering material having a metal-containing layer on one surface and a layer of a pressure sensitive adhesive on a second surface, as well as a layer of a puncture resistant material disposed between the metal-containing layer and the adhesive layer, cutting the covering manually at a job site to form a first sheet, removing the release liner covering the pressure sensitive adhesive on the first sheet, applying the first sheet to the insulation so that the adhesive layer bonds to the insulation and the metal-containing layer is exposed, and applying additional sheets of covering material directly to the insulation such that each sheet of covering material overlaps sheets of covering material directly adjacent thereto. In one embodiment, the method is used for covering an insulated duct having a substantially rectangular cross-sectional shape. In this embodiment, the applying steps include applying the first sheet of covering material to a bottom wall so that at least a three inch portion extends upwardly along each sidewall, applying a cut sheet of covering material to each side wall of the insulated duct so that it overlaps the portion of the sheet along the bottom wall which extends upwardly along the side wall, and so that a portion of the sheet material along each side wall extends along the top wall, and applying a fourth sheet of covering material to the top wall to overlap the portions of the sheets along the side wall which extend along the top wall. In another embodiment of the invention, where the pipe to be insulated has a curved portion, lengths of a pressure sensitive adhesive tape having a metal-containing foil layer and a puncture resistant polymer layer are wrapped about the sheets of covering material to conform the covering material to the configuration of the pipe. BRIEF DESCRIPTION OF THE DRAWINGS The objects, advantages and features of this invention will be more clearly appreciated from the following detailed description, when taken in conjunction with the accompanying drawings, in which: FIG. 1 is a cross-sectional view of a cutaway portion of one embodiment of the facing of this invention; FIG. 1A is a cross-sectional view of a cutaway portion of another embodiment of the facing of this invention; FIG. 1B is a cross-sectional view of a cutaway portion of yet another embodiment of the facing of this invention; FIG. 2 is a cross sectional schematic view of rectangular duct work illustrating a method for applying the facing of FIG. 1 to duct work: FIG. 3 is a perspective schematic view illustrating a method for applying the facing of FIG. 1 to a cylindrical, straight pipe; FIG. 4 is a perspective, schematic view illustrating a method for applying the facing of FIG. 1 to a curved pipe; FIG. 5 is a perspective, schematic view illustrating a method for applying the facing of FIG. 1 to a reduced portion of rectangular duct work; FIG. 6 is a perspective, schematic view illustrating a method for applying the facing of FIG. 1 to a reduced pipe; FIG. 6A is a plan view of a precut facing segment to be applied to a tapered portion of a reduced pipe; FIG. 7 is a perspective schematic view illustrating a method for applying the facing of FIG. 1 to a T-section pipe; FIG. 7A is a plan view of precut facing segments to be applied to a T-section pipe; and FIG. 8 is a cross-sectional view of a cutaway portion of a wrapping tape to be used in the method of this invention. DETAILED DESCRIPTION With reference now to the drawings, and more particularly to FIG. 1 thereof, one embodiment of the facing structure of this invention will be described. Facing 10 includes multiple layers of a metal or metalized foil and a puncture-resistant polymer film which are laminated together. The layers of foil provide the desired vapor seal, weather resistance, and a desirable exterior appearance. The layers of polymer provide puncture and tear resistance, particularly with respect to birds and other animals. All of the materials together provide the desired fire resistance and resistance to flame spread. The number of layers of foil and polymer, the thickness of each layer, and the actual materials forming the layers are chosen to provide a facing which optimizes each of the desired properties. For example, thick layers of metal would provide additional resistance to weathering, impermeability to moisture, resistance to puncture, and additional strength. However, if the metal layers become too thick, they cannot be easily cut and manually applied at the job site. The material also could become too heavy to be easily manipulated, conformed and applied by the average worker. Similarly; additional layers of a polymer film, or greater thicknesses of polymer film would increase the puncture resistance of the facing but could also increase the weight, reduce the conformability and render cutting more difficult, thus making it very difficult to apply at the job site and to conform it to the shape of the fluid conduits about which it is to be wrapped. Any failure to conform the facing closely to the shape of the insulation surrounding the conduit could produce gaps through which moisture or wind could enter, thus destroying the weather and vapor seal and permitting the damage to the insulation it is designed to prevent. Different materials also provide different advantages. For example, steel provides greater strength and puncture resistance, while aluminum is lighter in weight, cheaper, more easily cut and more flexible. A metalized foil is lighter in weight than most metal foils, but generally is not as strong or as impermeable to moisture. Polytetrafluoroethylene (PTFE) is water proof, but is hard to cut and expensive. Polyester is cheaper and easier to cut and use than PTFE. The embodiment illustrated in FIG. 1 represents a consideration of all of these factors and a balancing of the desired properties to achieve an optimal result. This embodiment includes a first layer 12 of a metal-containing foil, a layer 14 of a polymer film, another layer 16 of a metal-containing foil, another layer 18 of a polymer film, and a third layer 20 of a metal-containing foil. A pressure sensitive adhesive layer 22 is disposed adjacent foil layer 20. Prior to application, pressure sensitive adhesive layer 22 is covered by a release liner 24. Layers 12, 16 and 20 typically are formed either of a metalized foil or of a metal foil. In one embodiment, layers 12, 16 and 20 are formed of an aluminum foil. It is understood however, that other metal foils could be used for layers 12, 16 and 20, such as a stainless steel foil, a titanium foil, a copper foil, or the like. In another embodiment, foil layers 12, 16 and 20 are formed of a metalized foil. Metalized foils suitable for use in this invention include conventional, commercially available foils in which a metal, such as aluminum, steel or titanium, is vapor deposited on a substrate formed of a polymer, such as polyvinyl fluoride (sold under the name TEDLAR®), polyethylene or biaxially oriented polypropylene. Since metalized foils tend to have pin holes resulting from handling during manufacture or other causes, it is preferred that not all of layers 12, 16 and 20 be formed of a metalized foil. Preferably, at least one of layers 12, 16 and 20 is formed of a metal foil, such as aluminum. In a preferred embodiment, at least layer 12 is formed of a metal foil, although it is understood that layer 12 could be formed of a metalized foil, so long as one of layers 16 and 20 is formed of a metal foil. If only one of layers 12, 16 and 20 is formed of a metal foil, it is preferred that such a layer have a thickness of at least nine microns to provide the desired impermeability to moisture. If more than one of layers 12, 16 and 20 is formed of a metal foil, it is preferred that the total thickness of metal foil layers in facing 10 be at least nine microns, and more preferably 25 microns. Layers 14 and 18 typically are formed of a polyester film although other polymer films such as polypropylene, polyethylene, polyurethane, Nylon®, Dacron®, Kevlar®, or polytetrafluoroethylene could be used. Layers 12, 14, ,16, 18 and 20 preferably are laminated or bonded together such as by an adhesive. This laminating adhesive could be a pressure sensitive adhesive or any conventional, flame retardant adhesive which is suitable for laminating a metal foil to a polymer, and which has high strength and durability. In one embodiment, a conventional urethane laminating adhesive is used, such as that, sold under the name Boscadur and purchased from the Bostik Chemical Division of the Emhart Fastener Group in Middleton, Mass. 01949. Another adhesive is sold under the name Adcote by Rohr & Haas. Typically, these laminating adhesives are provided in layers of about 0.3 to 2.0 mils and coating weights of about 3 to 11 pounds per 1000 square feet. Layer 22 of a pressure sensitive adhesive can be any commercially available, pressure sensitive adhesive that is suitable for bonding to a metal or metalized foil and to kraft paper or other insulation surfaces, and which maintains its integrity under low and high temperature conditions. Examples of such suitable pressure sensitive adhesives are disclosed in U.S. Pat. No. 4,780,347, which is specifically incorporated herein by reference. In particular, one suitable adhesive is a pressure sensitive, acrylic adhesive, which when cured, approaches a 100% acrylic compound in which substantially all solvents have been removed. This adhesive can, however, tolerate up to 1% solvents after curing and still perform as desired. When cured, layer 22 formed of this particular acrylic adhesive typically has a thickness of between about 1.0 and 5 mils and a coating weight of about 5.5 to about 27.5 pounds per 1000 square feet. This particular acrylic adhesive is especially desirable, since it remains tacky and useable at temperatures as low as minus 17° Fahrenheit and as high as 284° Fahrenheit. Release liner 24 can be any conventional release liner suitable for use with an acrylic adhesive. A typical release liner is a silicone coated, natural kraft paper release liner rated at 70 pounds per ream. In one embodiment, where foil layers 12, 16 and 20 are formed of a metal foil, each layer 12, 16 and 20 is about 9 microns in thickness. However, especially for aluminum foils, thicknesses as low as 5 microns also would be suitable for many applications, while thickness as great as 50 microns would be acceptable, since facing 10 would still be cuttable with a knife or scissors and would still be sufficiently conformable to be used in covering most types of installations in most applications. In one embodiment, layers 14 and 18 may be about 23 microns or greater in thickness. However, it is to be understood that layers 14 and 18 could be thinner than 23 microns, depending upon the degree of puncture and tear resistance desired. In fact, layers 14 and 18 could be as thin as 5 microns for certain applications. In addition, these layers 14 and 18 may also be as thick as 50 microns so long as the resulting facing 10 is still adequately conformable to the shape of the fluid conduit and the insulation surrounding it, and the facing 10 could still be cut with scissors or a knife. Preferably, the total thickness of facing 10 is 100 microns or less to allow it to be easily cut and handled at the job site. If the facing could be precut at the factory prior to transportation to the job site, much thicker layers of polymer and foil could be utilized to provide enhanced performance as long as the material still conformed to the outer shape of the insulation-covered conduit. In one embodiment in which layers 12, 16 and 20 are formed of an aluminum foil having a thickness of about 9 microns, and in which layers 14 and 18 are formed of a polyester film having a thickness of about 23 microns, the total thickness of facing 10, not including adhesive layer 22, is about 85 microns. This thickness includes the thicknesses of the laminating adhesives used to bond together the layers. In this embodiment, a typically thickness of adhesive layer 22 is about 0.079 millimeters with a coating weight of about 50 grams per square meter. The peel adhesion is about 30 ounces per inch and the sheer adhesion is indefinite at 2.2 pounds per square inch. The tensile strength measured according to PSTC-31 is about 50 pounds per inch width. The elongation at break is at about 166%. The puncture resistance according to ASTM D-1000 is about 16 kilograms, while the tear strength according to ASTM D-624 is about 2 kilograms. A maximum temperature for continuous use is about 300° Fahrenheit (149° C.), and the application temperature ranges from minus 17° Fahrenheit to 284° Fahrenheit (minus 27° C. to plus 140° C.). Facing 10 has no permeability to water vapor. Facing 10 has a chemical and ultraviolet resistance which is comparable to that of aluminum. FIGS. 1A and 1B illustrate other embodiment of the facing 10 of this invention. Like numbers are used for like parts, where appropriate. In FIG. 1A, a protective layer 26 is disposed on top of layer 12 of facing 10. Protective layer 26 protects layer 12, and thus all of the layers below layer 12 from damage caused by the environment. Preferably, protective layer 26 protects against damage due to ultraviolet radiation, and/or acid rain, and/or salt and/or other corrosive materials found in the environment. In one embodiment, protective layer 26 is a cured epoxy coating which is deposited on layer 12 while wet and allowed to cure. Other materials which could be used for layer 26 include a urethane material, polyvinyl fluoride, an acrylic material, a metalized film of polyvinyl fluoride, a metalized titanium film, a layer of silica vapor deposited upon layer 12 or layer of Saran®. In another embodiment, as illustrated in FIG. 1B, facing 10 could be provided without adhesive layer 22 or release liner 24. In the absence of adhesive layer 22, a user could apply facing 10 directly to insulation at the factory prior to shipment to a job site. In such an instance, the facing 10 could be applied utilizing a conventional hot melt adhesive, or any other standard adhesive. If facing 10 of FIG. 1B is sent directly to the job site, the user could apply facing 10 to the insulation utilizing a mastic, or conventional adhesive, which is either applied to layer 20, or which is applied to the insulation prior to application of the facing 10. Another alternative embodiment of the structure of FIG. 1 is illustrated in FIG. 1A in which an additional layer 15 is incorporated into the structure of FIG. 1 between a layer 12 of a metal-containing foil and a layer 14 of polymer film. This additional layer 15 can be incorporated-between any two layers in the structure, but typically is not disposed on an outside surface, or adjacent adhesive layer 22. This layer could be formed of a fiberglass scrim, a polyester scrim, a woven fabric or a fiberglass and a polyester scrim. The woven fabric could be formed of a polypropylene or a polyester thread. Such a layer 15 provides additional tensile strength, and tear resistance. In addition, a scrim layer produces a pattern on the exterior surface of facing 10 that is rectangular in shape, and that aids the installer in properly aligning the facing 10 on the insulation. Moreover, additional layers of a metal-containing foil and a polymer could be added to the structure of FIG. 1 so long as the resulting product were sufficiently conformable, easy to cut and lightweight. Additional layers could be accommodated by making thinner the alternating metal-containing layers and polymer layers. In addition, it is to be understood that layer 22 of a pressure sensitive adhesive could be applied to polymer layer 18 rather than to a metal-containing layer, as illustrated in FIG. 1. Methods of use of facing 10 in various applications will now be described with reference to FIGS. 2-7. Before applying the facing 10 to any surface, it is important that the surface be dry, clean and free from dust, oil and grease or silicone. Facing 10 should be cut to size prior to application. Typically, cutting to size is performed at the jobsite so that the worker can measure the fluid conduit or duct work on the spot and cut the facing to the precise size desired. However, facing 10 could be precut at the factory, particularly for the portions used on curved pipes, as shown in FIG. 4, or on T-sections, as shown in FIG. 7. Typically, facing 10 comes in large rolls which are unrolled and then cut with scissors, knives, box cutters or the like. It is important that the sheets of facing 10 be applied in an overlapping fashion, to provide a weather and vapor proof seal. A three inch (75 millimeter) overlap is recommended. When applying sheets of the facing 10, typically release liner 24 is peeled back from one edge and creased to expose adhesive layer 22 along that edge. This edge is then adhered to the surface to which the facing is to be applied, and thereafter, release liner 24 is peeled away from adhesive layer 22 as the facing is applied, such as by use of a spreader which smoothes the facing and the insulation surface. One method for applying a sheet of facing 10 to rectangular duct work 30 is illustrated in FIG. 2. Typically, a sheet 32 of facing 10 is first applied to the bottom wall 31 of the duct 30 and the necessary overlap 34 is provided along walls 33 and 35. Typically, one edge of sheet 32 is first adhered to wall 33 or 35 to provide overlap 34, while the remainder of the sheet 32 remains covered by release liner 24. As sheet 32 is secured to wall 31, release liner 24 is peeled away from adhesive layer 22 just prior to adhering sheet 32 to wall 31. The process continues until all of wall 31 is covered, and the necessary overlap 34 is provided along the other of wall 33 or 35. Thereafter, another sheet 36 or 38 of facing is applied along respective wall 33 or 35. In both instances, the overlap 34 typically is provided along wall 37. Once walls 33 and 35 have been covered, top wall 37 is covered in the manner previously-described with sheet 40. Sheet 40 need not overlap walls 33 and 35. Typically, no additional sealing tape is required for such rectangular duct work 30, or the like. This process is repeated along the entire axial or longitudinal length of the duct work 30 with additional sheets of facing 10 that overlap adjacent sheets in a longitudinal direction along circumferentially extending edges. This technique is particularly advantageous for large, flat horizontal ductwork upon the top wall 37 of which water tends to pool. By using a sheet on the top wall 37 that extends the width of the wall and overlaps walls 33 and 35, there are no seams into which the pooled water may seep. An example of a method of application of this facing 10 to a straight circular pipe 48 is illustrated in FIG. 3. In this example, a series of sheets 52 having the same width and length are cut from rolls of the facing 10 prior to installation. Each sheet 52 is sized so that when wrapped about the insulation 46 on pipe 48, a suitable circumferential overlap 50 results along axially extending edges. Similarly, when successive sheets 52 are applied, there should be an overlap 54 between each successive sheet 52 in an axial direction along circumferentially extending adjacent edges. Each sheet 52 is otherwise applied in the same manner as described with respect to FIG. 2. FIG. 4 illustrates one example of application of facing to a curved pipe 64. Initially, sheets 60 are applied in a manner virtually identical to sheets 52 of FIG. 3. Successive sheets 60 are cut and applied in an overlapping manner to insulation 62 along the axial length of pipe 64. One difference between the method of FIG. 3 and that of FIG. 4 is that the sheet 60 applied to the curved portion 66 of pipe 64 typically would be narrower in width in an axial direction than sheets 60 covering the straight portion of the pipe 64, since facing 10 may not conform as easily to the shape of the curved portion 66 of the pipe 64 as it does to the straight portions because of a slight inherent rigidity caused by the multiple layers of foil and polymer. To assist in conforming sheet 60 to the shape of the curved portion 66 of the pipe 64, in some applications, it may be desirable to apply a wrapping of a tape 68 at axially spaced intervals, as shown. Tape 68 typically is wrapped so as to overlap itself circumferentially and should be applied at whatever axial intervals are necessary to conform sheet 60 to the shape of curved portion 66. A tape 68 typically used for this purpose is a tape which has the same vapor barrier, weathering characteristics, and appearance as facing 10. In one example, as shown in FIG. 8, tape 68 is formed of a film 28 of a polymer disposed between two layers 27 and 29 of a metal-containing foil. The layers are laminated together using a laminating adhesive, like that used for facing 10. Like layers 12, 16 and 20 of facing 10, layers 27 and 29 could be formed of a metalized foil or a metal such as aluminum, while the polymer film 28 can be formed of the same materials as layers 14 and 18 of facing 10, such as polyester. Layers 27 and 29 and polymer film 28 could be of the same construction and thickness as respective layers 12 and 14 found in facing 10. Typically, a pressure sensitive adhesive layer 25, similar to adhesive layer 22, is disposed on layer 29, and a release liner 23, such as release liner 24 is applied to the layer 25 of pressure sensitive adhesive. FIG. 5 illustrates one example of the application of facing 10 to a reduced section of duct work 69. A first trapezoidal segment of facing is cut and applied to surface 70. This trapezoidal segment should provide the desired overlap on each adjoining surface, including surfaces 74, 76, 78 and 80. Next, trapezoidal segments of facing are cut for surfaces 74 and 80, providing the necessary overlap along adjoining surfaces 70, 86, 88 and 82. Thereafter, a final trapezoidal segment of facing is cut and applied to surface 82 with overlap provided along surfaces 90, 84, 80 and 74. Next, sheets are cut having the necessary circumferential length to be wrapped about surfaces 76, 88 and 90 with the necessary axial overlap along circumferential edges as well as with the necessary overlap with each of the trapezoidal segments on surfaces 70, 80, 82 and 74 and adjacent sheets in an axial direction along circumferentially extending edges. Finally, sheets of facing are cut to be wrapped about surfaces 78, 84 and 86 to provide the necessary overlap with the trapezoidal segments on surfaces 80, 82, 74 and 70, with adjoining sheets in an axial direction along surfaces 84, 86 and 78, and with-themselves in an axial direction along circumferentially extending edges. Each sheet is applied as previously described. FIG. 6 illustrates one example of the application of facing 10 to a reduced pipe 99. Typically, a sheet of facing is first applied to surface 100 which is the reduced portion 101 of the pipe 99 just adjacent the tapered portion 102. A sheet of facing is cut and wrapped about surface 100 in the manner previously described. Thereafter, a C-shaped section 105 of facing (see FIG. 6A) is cut and applied to the tapered portion 102, providing overlap with the material on surface 100. Sheets of facing 10 then are cut and applied to surface 104 of the enlarged portion 103 of the pipe 99. These sheets are applied one adjacent another along the length of surface 104 so as to provide overlap with each other in an axial direction and to provide overlap with themselves as shown in a circumferential direction. Finally, sheets of facing are applied to surface 106 in overlapping relationship with one another along the axial length, and with themselves in a circumferential direction, as previously described. FIGS. 7 and 7a illustrate one example of the application of facing 10 to a T section of a pipe 116. A first sheet 110 is cut having the configuration shown in FIG. 7a. Sheet 110 is provided with cutouts 112 to accommodate the T section 114,of pipe 116. Thereafter, a sheet 120 is cut to the shape shown in FIG. 7a. Sheet 120 is then applied to section 114 in the manner shown, so that there is overlap between edge 122 of sheet 120 and edge 124 on sheet 110. Thereafter, additional overlapping sheets may be applied to segment 114, as well as to portion 126, as previously described with respect to a straight pipe in FIG. 3. Preferably a length of tape 128, like tape 68, is applied at the junction of edges 122 and 124 to effect a vapor tight seal. The facing 10 of this invention, when used with insulation for a fluid conduit, such as a pipe or duct work, provides a vapor tight seal about the insulation and duct work or pipe that is weather resistant, puncture and tear resistant, sufficiently flexible, easily cut, and aesthetically pleasing. Facing 10 can be applied in almost all weather conditions, and in a temperature range from minus 17° to plus 284° Fahrenheit. The resulting sealed pipe or duct work is fire resistant, and any flame would spread very slowly. Facing 10 can be easily repaired onsite, and has a long life. The method of this invention provides an easy technique for applying facing to insulation disposed on duct work or on pipes and can be mastered with very little training or skill. Installation is fast, clean and safe. Only scissors and a knife or the like are required as tools, and all work can be done at the job site. No prior or cuffing or assembly is required. Modifications and improvements will occur within the scope of this invention to those skilled in the art. The above description is intended as exemplary only, the scope of this invention being defined by the following claims and their equivalents. | <SOH> BACKGROUND OF THE INVENTION <EOH>Pipes or duct work in dwellings, commercial buildings and industrial plants are used for heating or air conditioning purposes and therefore carry fluids, such as heated or cooled air, or steam. In industrial applications, pipes or duct work also may carry chemicals or petroleum products or the like. Such pipes our duct work and associated heating or air conditioning units typically are covered with an exterior layer of insulation. The duct work typically is formed of aluminum or steel, while the pipes may be formed of any suitable material, such as copper, steel, aluminum, plastic, rubber or other like materials. The insulation used to cover such pipes or duct work and associated heating and air conditioning units often includes fiberglass or mineral wool, foamed cellular glass or a rigid foam, covered by a jacket of foil or a layer of paper, such as kraft paper. Other layers of materials may be included in the insulation jacket, such as a layer of foil, a scrim, or a layer of polyester. Duct board is often used to cover duct work. When such pipes or duct work are in a location exposed to weather or when they are in other environments where the exterior insulation surface is subject to degradation by moisture or the like, it is common to cover the insulation with a facing. This is particularly true for insulation having an exterior layer of paper or for duct board, (whether or not the surface is a metalized layer or a paper layer) to protect the insulation from moisture, sun, wind or other weather elements. In one existing example, sheet metal cladding is applied to the exterior surface of the insulation. Such cladding typically is formed of aluminum, stainless steel, galvanized steel, or another like metal. This cladding has certain drawbacks including the fact that such cladding is very expensive and time consuming to install. In addition, metal cladding is not water or vapor tight or weatherproof because of joints, any repairs can be quite costly, prefabrication of the cladding is required off site, and metal cladding is very heavy and therefore difficult to handle. Another existing solution is to cover the insulation with butyl rubber. However, this solution also has drawbacks including the fact that the butyl rubber does not perform well and tends to delaminate, particularly in extreme weather conditions. Butyl rubber also is very difficult to apply because it is messy to cut and form, and it is very heavy. Moreover, butyl rubber has been known to cause delamination of the outer surface of the insulation from the fiberglass or the wool disposed in the interior because of its weight and because of its lack of strength at elevated temperatures. A butyl rubber covering tends to have a poor appearance, and does not perform well at temperatures below zero degrees Fahrenheit or above 120° Fahrenheit and therefore should not be used in extreme weather environments where such exterior coverings are most desired and are often necessary. Butyl rubber also tends to creep, has a poor fire and smoke rating, and therefore is not UL listed. Finally, solvents are required to activate butyl rubber at temperatures below 45° F. It is also known to cover insulation with thin layers of aluminum foil using a butyl rubber adhesive. However, such coverings have little or no puncture resistance and the adhesive layer has the same drawbacks noted above, including a tendency to run or ooze at elevated temperatures. Scrim and mastics are also used to cover insulation. However, the use of such materials often is very labor intensive and requires a multiple step process. These products can only be applied during certain weather conditions, and it is very difficult to regulate the thickness of mastic to make it uniform. Consequently, such products have very limited applications, and generate a poor appearance. Another known product is bitumen felt and netting. This product is very labor intensive to apply and is not recommended for exterior use. It also has a very poor fire rating, and is unsightly. Thus, its use is very limited. In view of the foregoing, there exists a need for a material or facing for covering insulation, particularly exterior insulation, that is relatively inexpensive, easy to apply, provides a good appearance and provides the desired vapor and weather seal. There also is a need for a product which is fire resistant, has low maintenance costs and can be used in extreme temperature conditions. | <SOH> SUMMARY OF INVENTION <EOH>This invention relates generally to a facing material for application to exposed surfaces of insulation or other like materials to provide a vapor seal and to protect the insulation from weather related damage. The facing of this invention overcomes the drawbacks of the prior art systems discussed above, since it is relatively inexpensive, is easy to apply, provides a good appearance, is easily cut and manipulated at the job site and provides a 100% vapor seal. The facing of this invention also can be applied and will maintain its integrity in extreme weather conditions and is very fire resistant. This invention also relates to a method for applying a facing to insulation. In one aspect, the invention includes a facing for insulation. One embodiment of the facing includes a first layer of a metal-containing foil, a second layer of a metal-containing foil, a third layer of a metal-containing foil, and a first layer of a puncture resistant polymer film disposed between the first and second layers of foil, and a second layer of a puncture resistant polymer film disposed between the second and third layers of foil. In another embodiment, a layer of pressure sensitive adhesive is applied to the third layer of foil. In yet another embodiment, at least the first layer of metal-containing foil may be formed of aluminum. In another embodiment, at least the first layer of the puncture resistant polymer film is formed of polyester. A typically thickness for the metal-containing foil layers is about 9 microns, while a typical thickness of the puncture resistant polymer film layers is about 23 microns or greater, although the polymer film layers could be as thin as 5 microns. In another aspect, a weather seal for use on exposed surfaces is disclosed. This weather seal includes a first layer of an aluminum foil, a second layer of a metal-containing foil, a third layer of a metal-containing foil, a first layer of a puncture resistant material disposed between the first layer of aluminum foil and the second layer of metal-containing foil, a second layer of a puncture resistant material disposed between the second and third layers of metal-containing foil and a layer of a pressure sensitive adhesive disposed on the third layer of metal-containing foil. In one embodiment, the first and second layers of puncture resistant material are formed of polyester. In another embodiment, the combined thickness of the weather seal is less than 100 microns. In another embodiment, the second and third layers of metal-containing foil are formed of a metalized foil. In another aspect, a covering for exterior and interior insulation is disclosed. This covering includes a first layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, a first layer of polyester adhered to the first layer of aluminum foil with an adhesive, the polyester layer having a thickness greater than about 23 microns, a second layer of aluminum foil adhered to the first layer of polyester material by an adhesive, the second layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, a second layer of polyester material adhered to the second layer of aluminum foil by an adhesive, the second layer of polyester material having a thickness greater than about 23 microns, a third layer of aluminum foil adhered to the second layer of polyester material by an adhesive, the third layer of aluminum foil having a thickness in the range of from about 5 microns to about 50 microns, and a pressure sensitive adhesive layer disposed on the third layer of aluminum foil. In yet another aspect of the invention, a covering for insulation is provided which includes multiple layers of a metal-containing foil and multiple layers of a puncture resistant, polymer film. The layers of puncture resistant polymer film are alternated with the layers of a metal-containing foil. The covering also includes a layer of a pressure sensitive adhesive disposed on one side of the covering, and on the other, exposed side of the covering, a layer of material resistant to ultraviolet radiation, acid rain, and salt. The covering is sufficiently flexible that it may be conformed to the shape of an insulated pipe. In another aspect, a method for protecting insulation from damage due to moisture and other environmental factors is disclosed. This method includes the step of providing a covering material having a metal-containing layer on one surface and a layer of a pressure sensitive adhesive on a second surface, as well as a layer of a puncture resistant material disposed between the metal-containing layer and the adhesive layer, cutting the covering manually at a job site to form a first sheet, removing the release liner covering the pressure sensitive adhesive on the first sheet, applying the first sheet to the insulation so that the adhesive layer bonds to the insulation and the metal-containing layer is exposed, and applying additional sheets of covering material directly to the insulation such that each sheet of covering material overlaps sheets of covering material directly adjacent thereto. In one embodiment, the method is used for covering an insulated duct having a substantially rectangular cross-sectional shape. In this embodiment, the applying steps include applying the first sheet of covering material to a bottom wall so that at least a three inch portion extends upwardly along each sidewall, applying a cut sheet of covering material to each side wall of the insulated duct so that it overlaps the portion of the sheet along the bottom wall which extends upwardly along the side wall, and so that a portion of the sheet material along each side wall extends along the top wall, and applying a fourth sheet of covering material to the top wall to overlap the portions of the sheets along the side wall which extend along the top wall. In another embodiment of the invention, where the pipe to be insulated has a curved portion, lengths of a pressure sensitive adhesive tape having a metal-containing foil layer and a puncture resistant polymer layer are wrapped about the sheets of covering material to conform the covering material to the configuration of the pipe. | 20050121 | 20051011 | 20050616 | 93407.0 | 1 | CHAN, SING P | FACING FOR INSULATION AND OTHER APPLICATIONS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,040,125 | ACCEPTED | Swaddling blanket | A swaddling blanket to alleviate colic has a back panel long enough to support a child from neck to feet, a leg pouch to loosely contain the child's legs, arm restraints to hold the child's arms against and parallel to the child's torso, a tapered short blanket arm to wrap over the child, and a tapered long blanket arm to wrap around the child more than once from the opposite direction to provide comforting pressure around the child's arms and torso. | 1. A swaddling blanket for a child, comprising: a back panel, the back panel having at least a first side; and a first blanket arm, the first blanket arm being integrated with the first side of the back panel to form a continuous sheet, neither the back panel nor the first blanket arm contacting the child's head when the child is swaddled by the back panel and the first blanket arm. 2. A swaddling blanket for a child as claimed in claim 1, wherein the back panel has a bottom edge and the swaddling blanket additionally comprises a leg pouch, the leg pouch having a bottom edge, the leg pouch being disposed upon the back panel with the bottom edge of the leg pouch proximate to the bottom edge of the back panel. 3. A swaddling blanket for a child as claimed in claim 1, additionally comprising an arm restraint, the arm restraint disposed upon the back panel. 4. A swaddling blanket for a child as claimed in claim 1, additionally comprising a first arm restraint and a second arm restraint, the arm restraints disposed upon the back panel. 5. A swaddling blanket for a child as claimed in claim 1, wherein the back panel has a second side and additionally comprises a second blanket arm, the second blanket arm being integrated with the second side of the back panel to form a continuous sheet, the second blanket arm not contacting the child's head when the child is swaddled by the back panel and the second blanket arm. 6. A swaddling blanket for a child as claimed in claim 5, wherein the second blanket arm is shorter than the first blanket arm. 7. A swaddling blanket for a child, comprising: means for supporting the child's back; means for restraining the child's arms; and means for applying circumferential inward pressure around the child's arms and torso, neither the means for supporting the child's back, the means for restraining the child's arms, nor the means for applying circumferential inward pressure around the child's arms and torso contacting the child's head while the child is swaddled in the blanket. | CROSS-REFERENCES TO RELATED APPLICATIONS This application claims the benefit of U.S. provisional patent application Ser. No. 60/399,679, filed by the same inventor on Jul. 31, 2002. This application is a continuation of U.S. utility patent application Ser. No. 10/622,705, filed by the same inventor on Jul. 21, 2003, now pending. BACKGROUND The swaddling of infants has been practiced since antiquity by people around the world. Swaddling protects an infant from the surrounding environment, allows a caregiver to handle and carry an infant more easily, and has long been thought to comfort and quiet an infant. This is especially true of “colicky” infants, those who cry at least three hours a day, three days a week, for at least three weeks in a row. Although no specific cause for colic has been identified and many potential remedies have been offered, research has shown that effective swaddling often has a calming effect on crying infants. Research also shows that a swaddled infant tends to be more willing to sleep on her back, which significantly reduces her vulnerability to Sudden Infant Death Syndrome. The key to effective swaddling appears to reside in a combination of factors. Loosely-swaddled infants tend to be more restless than snugly-swaddled infants, but overly tight swaddling may inhibit breathing. An infant is comforted by having her arms held snugly against her midsection and by having even pressure applied around her torso. Limitations on leg movement help also, but complete immobilization of the legs may promote hip dysplasia. Any pressure against the head is counterproductive. Too thin a wrap may provide inadequate restraint, but too heavy a wrap may overheat the infant. It is thought that gentle, even pressure around an infant's torso and immobilization of her limbs may simulate the pre-birth environment. Additionally, or alternatively, immobilization of the limbs may keep an infant from startling herself awake by reflexively flailing her limbs in her sleep and striking nearby objects. Pressure against the head is thought to awaken an infant by stimulating the “rooting” response, where the infant reflexively seeks a nipple. An ideal swaddling implement would therefore provide a means for immobilizing an infant's arms while placing gentle, even pressure on her torso; would restrict leg movement without excessive pressure; and would leave the infant's head unencumbered. In addition, the implement could be made of light fabric so that the infant would not overheat. The implement would be easy to use, allowing a quick, snug wrap without complex folding and tucking. Unfortunately, presently-available swaddling implements do not provide all of these features. Few people know how to securely and properly wrap an infant in a conventional blanket, and fewer still have the inclination to learn. The traditional “colic band,” a fabric strip that is wrapped around an infant's midsection, may provide some relief but does not properly contain the infant's arms and legs. Other available swaddling implements may be too loose to provide more than insulation, or too may be tight around the legs, or may have a hood that triggers the rooting response. SUMMARY The present invention remedies the defects of known swaddling implements, providing an easy-to-use swaddling blanket that immobilizes an infant's arms while placing gentle, even pressure on her torso, restricting leg movement without excessive pressure, and leaving the infant's head unencumbered. A preferred embodiment of the present invention has a back panel, a leg pouch, two arm restraints, and two blanket arms, and is made from any of a variety of fabrics. The back panel is both wide and long enough to support an infant from her neck to her feet. The leg pouch is formed from a roughly rectangular piece of fabric that is sewn to the back panel along three adjacent edges, with the bottom edge of the leg pouch sewn to the bottom edge of the back panel and the top edge of the leg pouch open. Each arm restraint is a tapered flap attached to the back panel with a seam that is beneath and parallel to an infant's arms when she is laid on her back on the back panel. Each arm restraint is positioned so that it may be wrapped inward around the adjacent arm. In this embodiment, each blanket arm is a side extension of the back panel and tapers to a broadly-rounded point. The back panel and the blanket arms may form a single, continuous piece of material, or the blanket arms may be attached to the sides of the back panel. One blanket arm is just long enough to wrap once over an infant and be tucked partially beneath the infant. The other blanket arm extends from the opposite side of the back panel and is long enough to wrap around the infant more than once. The taper of each blanket arm is such that when both blanket arms are wrapped around the infant, most of the blanket's bulk and pressure surround the infant's torso. To swaddle an infant with the present invention, the infant is placed on her back on the back panel, with her legs in the leg pouch and her shoulders just below the top edge of the back panel. Her arms are placed along her sides. An arm restraint is wrapped around each arm from the outside of each arm, first passing over an arm, then inward to be tucked under the arm. The shortest of the two blanket arms is wrapped over and across the infant and its tapered end is tucked under the armpit on the side of the longest blanket arm. The longest blanket arm is then wrapped snugly and repeatedly around the infant in the opposite direction. When an infant is swaddled in this manner, her legs are contained without being immobilized and she is comforted by having her arms and torso snugly wrapped. Nothing contacts her head to provoke a rooting response. The blanket material may be light, so that she does not overheat, or it may provide insulation for colder weather. Unlike a conventional blanket, the arm restraints and tapered blanket arms of the present invention allow a caregiver to quickly and securely wrap an infant with the exact amount of pressure desired, without having the swaddling unravel when the infant moves. Some of the benefits of the present invention may be obtained with a simplified embodiment consisting only of the back panel and tapered long blanket arm, which may form a single, continuous sheet of material. The dimensions of the back panel and the taper of the long blanket arm allow a more complete wrap and better pressure distribution than does the traditional colic band. However, addition of a leg pouch protects the infant's feet, simplifies positioning of the infant, and improves containment of the infant's legs. Addition of the arm restraints allows a caregiver to quickly secure an infant's arms close and parallel to the infant's torso. Addition of the short blanket arm allows a caregiver to quickly secure the top edge of the leg pouch and the infant so that the long blanket arm may be easily and carefully wrapped to obtain exactly the desired pressure distribution. All of these features and advantages of the present invention, and more, are illustrated below in the drawings and detailed description that follows. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a preferred embodiment of the present invention. FIG. 2A shows the embodiment of FIG. 1 with an infant whose legs are in the leg pouch. FIG. 2B shows the embodiment of FIG. 1 with arm restraints wrapped around an infant's arms. FIG. 2C shows the embodiment of FIG. 1 with a short blanket arm wrapped around an infant's torso and tucked beneath an armpit. FIG. 2D shows the embodiment of FIG. 1 with a long blanket arm wrapped repeatedly around an infant. FIG. 3 shows an alternate embodiment of the present invention with an extended leg pouch and a hook-and-loop attachment patch. FIG. 4 shows an alternate embodiment of the present invention with a leg pouch divided to accommodate a car seat strap. FIG. 5 shows an alternate embodiment of the present invention with a single large arm restraint pouch. FIG. 6 shows an alternate embodiment of the present invention with a divided arm restraint band. FIG. 7 shows an alternate embodiment of the present invention with two narrow arm restraint pouches. FIG. 8 shows an alternate embodiment of the present invention with two wide arm restraint pouches. DETAILED DESCRIPTION FIG. 1 shows a preferred embodiment of the present invention having a back panel 100, a leg pouch 110, a first arm restraint 120, a second arm restraint 125, a short blanket arm 130, and a long blanket arm 135. In this embodiment the back panel 100 is approximately as long and wide as the combined torso and legs of a typical infant. In this preferred embodiment, the back panel 100 measures approximately 60 cm by 25 cm. However, the back panel 100 and other parts of the invention can be scaled to fit a person of any size. The parts of the present invention are made from sheet material, usually fabric. Some fabrics used are cotton flannel, SPANDEX®, polyester, cotton/polyester blend, ribbed cotton, elastic cotton, cotton waffle, viscose georgette, polyester georgette, rayon, satin, cotton voil, terry voil, cotton crepe, rayon crepe, shantoon, flex, linen, poplin, cambric, sheeting, denim, silk denim, knits, cotton check, cotton crepe check, silk, terry cloth, and cotton interwoven with sterling silver thread. Many other fabrics known in the art may be used instead or in addition, depending on the desired characteristics such as elasticity, warmth, weight, breathability, stain resistance, absence of allergens, visual appeal, and other factors. The present invention may be made of a single material or parts may be made of different materials. Flexible, non-fabric materials may also be used to provide special characteristics. A short blanket arm 130 extends from a first side 102 of the back panel 100. The short blanket arm 130 tapers away from the back panel 100 to a first end point 133 and is about 40 cm long, just long enough to wrap once over an infant with enough excess length to tuck into the infant's armpit. The long blanket arm 135 extends from a second side 104 of the back panel 100. The long blanket arm 135 tapers away from the back panel 100 to a second end point 138 and is about 100 cm long, enough to wrap around the infant more than once, preferably at least twice. The blanket arms 130, 135 may be separate pieces sewn, bonded, electrically welded, or attached by other means known in the art to sides 102, 104 of the back panel 100, or the blanket arms 130, 135 and the back panel 100 may be of a single, continuous piece of material. The positions of the blanket arms 130, 135 may be reversed in any embodiment of the present invention without impairing the utility of the invention. In this preferred embodiment of the present invention, the lower edge 131 of the short blanket arm 130 tapers at a more acute angle with respect to the back panel 100 than the upper edge 132 of the short blanket arm 130, so that the first end point 133 is horizontally aligned with the center of the infant's torso. Also, the lower edge 131 of the short blanket arm 130 may curve toward the interior of the arm, eliminating excess material that might bunch and place unwanted pressure on the leg pouch 110. The short blanket arm 130 therefore wraps smoothly and securely around the infant's torso without interfering with leg movement. The upper edge 137 and the lower edge 136 of the long blanket arm 135 taper at approximately the same angle with respect to the back panel 100, so that the second end point 138 is horizontally aligned with the child's navel. Therefore, when an infant is laid on her back upon the back panel 100 with the tops of her shoulders approximately even with the upper edge 106 of the back panel 100, a straight line between the first end point 133 and the second end point 138 of the extended blanket arms 130, 135 would pass slightly above the infant's navel. In other embodiments of the present invention the upper and lower tapers of the blanket arms 130, 135 may be changed as necessary to effect desired pressure distributions. The leg pouch 110 is formed from a roughly rectangular piece of fabric that is sewn to the back panel 100 along a first edge 112, a second edge 114, and a bottom edge 118. A typical leg pouch measures approximately 25 cm wide by 30 cm long. The bottom edge 118 of the leg pouch 110 is sewn to the lower edge (not visible) of the back panel 100, leaving the top edge 116 of the leg pouch 110 open. Alternatively, the leg pouch 110 may be an extension of the lower edge of the back panel 100 folded upward and sewn along its vertical edges 112, 114. The vertical edges 112, 114 may also curve inward and outward to form an hourglass profile, allowing somewhat greater restriction of the infant's legs. The arms restraints 120, 125 are in a preferred embodiment tapered flaps attached to the back panel 100 at seams 121, 126 that lie beneath and parallel to an infant's arms. A typical seam is about 30 cm long. Each arm restraint 120, 125 tapers to a lobe 122, 127 and is positioned so that it may be wrapped inward around an infant's adjacent arm. A typical arm restraint measures about 25 to 30 cm from a seam 121, 126 to the end of a lobe 122, 127. The downwardly-tapering lobes 122, 127 relieve pressure on the infant's shoulders while providing an easily-used means for securing her arms. The lobe shapes minimize fabric bunching and optimize pressure distribution, but the arm restraints 120, 125 may also be triangular, rectangular, or any of a variety of other shapes as desired. It should be noted that some of the benefits of the present invention may be obtained with a simplified version consisting only of the back panel 100 and tapered long blanket arm 135. The dimensions of the back panel 100 and the taper of the long blanket arm 135 allow a more complete wrap and better pressure distribution than does the traditional colic band. However, addition of the leg pouch 110 protects the infant's feet, simplifies positioning of the infant, and improves containment of the infant's legs. Addition of the arm restraints 120, 125 allows a caregiver to quickly secure an infant's arms close and parallel to the infant's torso. Addition of the short blanket arm 130 allows a caregiver to quickly secure the top edge 116 of the leg pouch 110 and the infant so that the long blanket arm 135 may be easily and carefully wrapped to obtain exactly the desired pressure distribution. FIGS. 2A through 2D illustrate a preferred method for employing the present invention. FIG. 2A shows an infant lying on the back panel (not visible) with her shoulders aligned with the upper edge 106 of the back panel, her arms along her sides, and her legs in the leg pouch 110. FIG. 2B shows how the arm restraints 120, 125 are each wrapped around the outside of an adjacent arm, then inwardly so that the arm restraint lobes 122, 127 can be tucked between the infant's arms and torso, thereby holding the infant's arms in an optimum position while subsequent steps are performed. FIG. 2C shows how the short blanket arm 130 is wrapped over and across the infant and secured by tucking the first end point 133 between the infant's torso and the proximate arm restraint 125 and armpit, securing both the top edge (not visible) of the leg pouch 110 and the infant. Finally, FIG. 2D shows how the long blanket arm 135 is wrapped over the infant, then repeatedly around the infant until the second end point (not visible) is reached. The caregiver adjusts the tension on the long blanket arm 135 as it is wrapped to obtain the desired pressure on the infant, with the taper of the long blanket arm 135 tending to concentrate increased pressure under the regions wrapped with the most layers. The second end point 138 may be secured by tucking it under a layer of the long blanket arm 135, or by a hook-and-loop or other fastener as is known in the art. FIG. 3 shows an alternate embodiment of the present invention is which the top edge 316 of the leg pouch 310 arcs upward. The extra fabric allows the leg pouch 310 to be better secured by the short blanket arm 330. FIG. 3 also shows an optional hook-and-loop fastener 350 attached to the inner-end of the long blanket arm 335 near the second end point 338. FIG. 4 shows another embodiment of the present invention in which the lower portion of the leg pouch 410 is divided into a right leg pouch 411 and a left leg pouch 413, with a gap 415 between to accommodate the buckle of a child's car seat. FIG. 4 also shows a variation on the blanket arm 430, 435 tapers, where the upper edges 432, 437 have very slight tapers and the lower edges 431, 436 have more pronounced tapers, shifting the end points 433, 438 and the corresponding area of maximum pressure upward. This and other variations may be combined with other feature variations described herein. FIG. 5 shows another embodiment of the present invention in which an arm pouch 540 is sewn to the short blanket arm 530 along a side seam 542; to the short blanket arm 530, back panel 500, and long blanket arm 535 along a bottom seam 543; and to the long blanket arm 535 along another side seam 544. The top edge 541 of the arm pouch 540 is left open and is aligned with and slightly below the upper edge 506 of the back panel 500. In use, an infant's arms are inserted into the arm pouch 540 as the infant is laid upon the pouch, then the blanket arms 530, 535 are wrapped in the usual fashion. FIG. 6 shows another embodiment of the present invention in which an arm restraint band 640 is sewn to the short blanket arm 630 along a seam 642; to the back panel 600 along a center seam 643; and to the long blanket arm 635 along another seam 644. In use, an infant's arms are inserted under the arm restraint band 640 on either side of the center seam 643 as the infant is laid upon the band, then the blanket arms 630, 635 are wrapped in the usual fashion. FIG. 7 shows an embodiment of the present invention with separate arm pouches. A right arm pouch 745 is sewn to the short blanket arm 730 and the back panel 700, leaving open an upper edge 747. A left arm pouch 746 is sewn to the long blanket arm 735 and the back panel 700, leaving open an upper edge 748. In use, each of an infant's arms is inserted into an adjacent arm pouch 745, 746 as the infant is laid upon the back panel 700, then the blanket arms 730, 735 are wrapped in the usual fashion. FIG. 8 shows an embodiment of the present invention substantially the same as that shown in FIG. 7, but with larger arm pouches 845, 846. The principles, embodiments, and modes of operation of the present invention have been set forth in the foregoing specification. The embodiments disclosed herein should be interpreted as illustrating the present invention and not as restricting it. The foregoing disclosure is not intended to limit the range of equivalent structure available to a person of ordinary skill in the art in any way, but rather to expand the range of equivalent structures in ways not previously contemplated. Numerous variations and changes can be made to the foregoing illustrative embodiments without departing from the scope and spirit of the present invention. | <SOH> BACKGROUND <EOH>The swaddling of infants has been practiced since antiquity by people around the world. Swaddling protects an infant from the surrounding environment, allows a caregiver to handle and carry an infant more easily, and has long been thought to comfort and quiet an infant. This is especially true of “colicky” infants, those who cry at least three hours a day, three days a week, for at least three weeks in a row. Although no specific cause for colic has been identified and many potential remedies have been offered, research has shown that effective swaddling often has a calming effect on crying infants. Research also shows that a swaddled infant tends to be more willing to sleep on her back, which significantly reduces her vulnerability to Sudden Infant Death Syndrome. The key to effective swaddling appears to reside in a combination of factors. Loosely-swaddled infants tend to be more restless than snugly-swaddled infants, but overly tight swaddling may inhibit breathing. An infant is comforted by having her arms held snugly against her midsection and by having even pressure applied around her torso. Limitations on leg movement help also, but complete immobilization of the legs may promote hip dysplasia. Any pressure against the head is counterproductive. Too thin a wrap may provide inadequate restraint, but too heavy a wrap may overheat the infant. It is thought that gentle, even pressure around an infant's torso and immobilization of her limbs may simulate the pre-birth environment. Additionally, or alternatively, immobilization of the limbs may keep an infant from startling herself awake by reflexively flailing her limbs in her sleep and striking nearby objects. Pressure against the head is thought to awaken an infant by stimulating the “rooting” response, where the infant reflexively seeks a nipple. An ideal swaddling implement would therefore provide a means for immobilizing an infant's arms while placing gentle, even pressure on her torso; would restrict leg movement without excessive pressure; and would leave the infant's head unencumbered. In addition, the implement could be made of light fabric so that the infant would not overheat. The implement would be easy to use, allowing a quick, snug wrap without complex folding and tucking. Unfortunately, presently-available swaddling implements do not provide all of these features. Few people know how to securely and properly wrap an infant in a conventional blanket, and fewer still have the inclination to learn. The traditional “colic band,” a fabric strip that is wrapped around an infant's midsection, may provide some relief but does not properly contain the infant's arms and legs. Other available swaddling implements may be too loose to provide more than insulation, or too may be tight around the legs, or may have a hood that triggers the rooting response. | <SOH> SUMMARY <EOH>The present invention remedies the defects of known swaddling implements, providing an easy-to-use swaddling blanket that immobilizes an infant's arms while placing gentle, even pressure on her torso, restricting leg movement without excessive pressure, and leaving the infant's head unencumbered. A preferred embodiment of the present invention has a back panel, a leg pouch, two arm restraints, and two blanket arms, and is made from any of a variety of fabrics. The back panel is both wide and long enough to support an infant from her neck to her feet. The leg pouch is formed from a roughly rectangular piece of fabric that is sewn to the back panel along three adjacent edges, with the bottom edge of the leg pouch sewn to the bottom edge of the back panel and the top edge of the leg pouch open. Each arm restraint is a tapered flap attached to the back panel with a seam that is beneath and parallel to an infant's arms when she is laid on her back on the back panel. Each arm restraint is positioned so that it may be wrapped inward around the adjacent arm. In this embodiment, each blanket arm is a side extension of the back panel and tapers to a broadly-rounded point. The back panel and the blanket arms may form a single, continuous piece of material, or the blanket arms may be attached to the sides of the back panel. One blanket arm is just long enough to wrap once over an infant and be tucked partially beneath the infant. The other blanket arm extends from the opposite side of the back panel and is long enough to wrap around the infant more than once. The taper of each blanket arm is such that when both blanket arms are wrapped around the infant, most of the blanket's bulk and pressure surround the infant's torso. To swaddle an infant with the present invention, the infant is placed on her back on the back panel, with her legs in the leg pouch and her shoulders just below the top edge of the back panel. Her arms are placed along her sides. An arm restraint is wrapped around each arm from the outside of each arm, first passing over an arm, then inward to be tucked under the arm. The shortest of the two blanket arms is wrapped over and across the infant and its tapered end is tucked under the armpit on the side of the longest blanket arm. The longest blanket arm is then wrapped snugly and repeatedly around the infant in the opposite direction. When an infant is swaddled in this manner, her legs are contained without being immobilized and she is comforted by having her arms and torso snugly wrapped. Nothing contacts her head to provoke a rooting response. The blanket material may be light, so that she does not overheat, or it may provide insulation for colder weather. Unlike a conventional blanket, the arm restraints and tapered blanket arms of the present invention allow a caregiver to quickly and securely wrap an infant with the exact amount of pressure desired, without having the swaddling unravel when the infant moves. Some of the benefits of the present invention may be obtained with a simplified embodiment consisting only of the back panel and tapered long blanket arm, which may form a single, continuous sheet of material. The dimensions of the back panel and the taper of the long blanket arm allow a more complete wrap and better pressure distribution than does the traditional colic band. However, addition of a leg pouch protects the infant's feet, simplifies positioning of the infant, and improves containment of the infant's legs. Addition of the arm restraints allows a caregiver to quickly secure an infant's arms close and parallel to the infant's torso. Addition of the short blanket arm allows a caregiver to quickly secure the top edge of the leg pouch and the infant so that the long blanket arm may be easily and carefully wrapped to obtain exactly the desired pressure distribution. All of these features and advantages of the present invention, and more, are illustrated below in the drawings and detailed description that follows. | 20050121 | 20060516 | 20050616 | 74819.0 | 1 | TRETTEL, MICHAEL | SWADDLING BLANKET | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,040,190 | ACCEPTED | System for replacing a cursor image in connection with displaying the contents of a web page | A system for modifying a cursor image, as displayed on a video monitor of a remote terminal, to a specific image having a desired shape and appearance. The system stores cursor image data corresponding to the specific image, and a cursor display code. The cursor display code contains information in response to which the cursor image is modified to the specific image. A server computer transmits specified information to the remote terminal. The information includes at least one cursor display instruction. The cursor display instruction is operable to modify, in conjunction with the cursor information and the cursor image data, a cursor image displayed by a display of the remote terminal in the shape and appearance of the specific image. | 1. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information includes at least one stock price. 2. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information includes at least one baseball game score. 3. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information includes a temperature. 4. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information is updated periodically. 5. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information is updated as new content information becomes available. 6. A system for replacing an existing cursor image with content information responsive to displaying a contents of a web page, comprising: a cursor display code module, stored in a computer readable medium, operable to process at least one cursor display instruction associated with said web page, said processing of said at least one cursor display instruction replacing said existing cursor with said content information responsive to said web page being displayed, said at least one cursor display instruction including indication of said content information, wherein said content information includes financial information. | FIELD OF THE INVENTION This invention relates to computer networks and software, and more particularly, to a server system capable of modifying a cursor image displayed on a remote client computer. BACKGROUND OF THE INVENTION The World Wide Web (“WWW” or “web”) and online services such as America Online, in conjunction with faster and more powerful personal computers, have rendered the Internet and other interactive online computer networks accessible to millions of people all over the world. Concomitant with the emergence of this new communication medium, digital content providers have proliferated, providing online news, entertainment, games and all sorts of other content. As with other mass mediums, such as television, radio, and print publications, the entities that create such content seek to offset their expenses by selling advertising. With reference to the WWW, online advertising has become a multimillion dollar business, to the amount of approximately $300 million dollars in 1996. The most common type of online advertisement exists in the form of “banner advertisements”. Users of online services routinely encounter banner ads on the top, sides, and/or bottom of their video monitor screens when viewing a web page. Banner ads are generally square or rectangular boxes provided with some combination of graphics, color and text directed to the product or service being advertised. As such, the intention of these banner advertisements is to create impressions among online users and to convey some advertising message and/or logo Banner ads are usually provided on a web page in the form of a “hyperlink”, in which users who yield to the advertisement's solicitation to “Click Here” are transported to the web site of the manufacturer of the product or service being advertised, or to some other screen which provides additional information about the product or service. Unfortunately, banner ads occupy only a small portion of a web page. As the user scrolls down a page the banner ad disappears. Although online advertisers and content publishers have attempted to optimize the visibility of banner advertisements by placing them on a popular web page where they will have a greater chance of being seen, Internet users, nevertheless, can easily ignore or find ways to remove and eliminate from their view the banner ads which exist on the web pages they are viewing. As such, the banner ads are rendered ineffective in their aim to provide information about a product or service. Additionally, money spent to advertise a product may be wasted if users are able to ignore or remove the advertisements from the web pages they are viewing. Another method of online advertising involves the use of “frames” on a web page. Frames are a feature supported by the recent versions of leading web navigating programs known as browses, such as Netscape Navigator® and Microsoft's Internet Explorer ®. Frames generally divide up a user's screen so that the user can, for example, independently scroll down each of numerous frames which appear on the web page being viewed on the user's screen. Like banner advertisements, frames can be aesthetically unappealing as well as confusing to the user. Additionally, placement of advertising frames on a web page generally results in cramping or decreasing the size of the main content frame which oftentimes renders the content in the main frame difficult to read. As a result, users have developed ways to reduce the size or even eliminate frames from the web page being viewed. Another type of online advertising involves the self-appearing window which generally appears on its own as a user is using the Internet or browsing on the WWW. Such advertisements are relatively easy for a user to avoid as a user may simply re-size the window to make it smaller drag another window or object in front of it to obscure it from view, close the advertising window, or simply ignore it and continue with the task being undertaken online. Recently, online advertisers have begun using self-appearing screens which are delivered via dialog boxes which dominate the main part of the screen. Although these dialog boxes can be removed when the user clicks on the appropriate place(s) on the dialog box, the self-appearing dialog boxes have a much higher rate of being seen by users. This follows because the dialog boxes take control of the user's screen for a preset amount of time and/or until the user clicks on the appropriate place(s) to make the dialog box disappear. The recent prevalence in the use of self-appearing dialog box advertising has resulted in a more intrusive method of advertising which has resulted in resentment among users who are accustomed to more passive online advertising methods such as the frames and banner advertisements which are more easily avoided and/or ignored. Accordingly, there is a need for a simple means to deliver advertising elements, i.e. logos, animation's, sound, impressions, text, etc., without the annoyance of totally interrupting and intrusive content delivery, and without the passiveness of ordinary banner and frame advertisements which can be easily ignored. OBJECTS AND SUMMARY OF THE INVENTION It is thus a general object of the present invention to provide a means for delivering online advertisements which are unintrusive and which are not easily ignored by a user. A more specific object of the present invention is to provide a server system for modifying a cursor image to a specific image displayed on a video monitor of a remote user's terminal. It is another object of the present invention to provide a server system for modifying a cursor image to a specific image displayed on a video monitor of a remote user's terminal for the purposes of providing on-screen advertising. It is a further object of the present invention to provide a means for providing on-screen advertising transmitted online which does not interrupt the delivery of content and which is aesthetically appealing and which affords the advertiser a great degree of unintrusive exposure. It is still a further object of the present invention to provide a system and a method for causing a remote user terminal to display a cursor image as specified by a server terminal. It is also an object of the present invention to provide a system and method for causing a remote user terminal to display a cursor image as specified by a server terminal, wherein the cursor image corresponds to the content retrieved by the user terminal. It is a further object of the present invention to provide a system and method for causing a remote user terminal to display a cursor image such as a corporate name or logo, a brand logo, an advertising or marketing icon or slogan, an animated advertising image, and a related audio clip, that relate to an advertisement, such as a banner advertisement, that is included in the information content being retrieved by the user terminal. It is an additional object of the present invention to provide a means for changing a cursor's appearance by sending data and control signals from a remote computer so that the cursor or pointer's appearance is associated with a portion of, or the entire content being displayed on the user's screen. It is still an additional object of the present invention to provide a means for changing the appearance of a computer's cursor or pointer by sending data and control signals from a remote computer so that the cursor or pointer's appearance is associated with advertising messages. These and other objects of the invention are realized in various embodiments of the present invention by providing a system for delivering advertising elements online without the annoyance resulting from the interruption of content delivery and without the passiveness of ordinary banner and frame advertisements which can be too easily ignored or bypassed or removed. An exemplary embodiment of the present invention is directed to a system that provides online advertising content using the on-screen cursor which is generally controlled by an input of positioning device known as a “mouse” or “mouse pointer”. Nearly all online computer interfaces utilize a wired or remote control positioning device such as a mouse or roller or track ball which controls the cursor's movement on the screen. It is the cursor controlled by the mouse or positioning device which a user uses to “navigate” or move the cursor over objects, buttons, menus, scroll bars, etc., which appear on-screen and then clicking or in some cases double-clicking in order to activate a screen or task, or to commence an application or some function. As a result of the prevalence of the use of the mouse, by many millions of users of online systems, a great deal of time is spent focused on the icons which represent the cursor or pointer as it may appear in some cases. Presently, pointer icons change from application to application and can also change within an application depending upon where on the screen the pointer is located, what state the computer exists in at a given moment, and what tools are being used, among other factors. Generally, pointers change shape to reflect an internal state of the computer or the present function within an application. While it is not new for pointers and cursors to change shape, pointers are not presently used to convey advertising. In conventional systems, the appearance of the cursor or pointer does not change to correspond with on-line content being displayed on the screen. The present invention provides a means for enabling cursors and pointers to change color, shape, appearance, make sounds, display animation, etc., when the user's terminal or computer, known as the “client” or “user” terminal, which has a network connection, receives certain instructions from a remote or “server” computer attached to the network. In an exemplary embodiment of the present invention, the generic cursor or pointer icons used in many networking applications, such as black arrows, hands with a pointing finger, spinning wheels, hourglasses, wristwatches, and others, will change appearance, and in some cases may incorporate sound or animation, in a way that is linked and related to the content, such as a web page, which is being transmitted to and displayed on the client computer. The cursor or pointer may appear as a corporate or a brand logo which relates to advertising content within the web page being transmitted and displayed. The cursor or pointer image may also appear in a specified shape or color that is intended to convey a message that relates to the advertising content within the web page being transmitted and displayed. An exemplary embodiment of the present invention comprises a combination of hardware and enabling software residing on the transmitting (server) computer or network server and/or on the receiving (client or user) computer or terminal which brings about the stated effect of enabling a computer's cursor or pointer to change appearance and in certain cases provide sound and animation which is linked and related to the content being transmitted to and displayed on the client computer or terminal. The transmitting computer and receiving computer or terminal advantageously include a processor, an operating system (OS) loaded thereon, a video monitor used to display a graphical user interface (GUI) and a Hypertext Transfer Protocol (HTTP) compliant web browser capable of loading and displaying hypertext documents transmitted over the Internet, although the invention is not limited in scope in that respect. For example, the receiving terminal may be any device that is able to communicate with a remote server, such as a user computer terminal, a user dumb terminal, or a television based system, such as Web TV® terminal and other devices. Preferably, coded information for bringing about the change in appearance of the cursor are embedded within the web page being loaded and viewed. In one embodiment of the present invention, the web page is written in Hypertext Markup Language (HTML) which is one of the most common standard page description languages used to develop web pages. Typically a web browser retrieves a web page to be loaded on user's terminal. The retrieved web page in accordance with one embodiment of the invention contains a set of predetermined instructions referred to herein as cursor display instructions. The browser or browser extension interprets the information contained in cursor display instructions and instructs the operating system of the user's terminal via an application programming interface (API) to check its memory to determine if the user terminal is capable of loading the coded image, animation, and/or soundbite. If the image, etc. has been previously cached in the client computer memory, the cursor display instructions instruct one or more of the many devices controlled by the operating system in the user's terminal, such as the video monitor and audio speakers to display the desired images, animation and play desired sounds. If the image, etc. has not been previously cached in the client computer's memory, the browser or browser extension retrieves the information corresponding to the desired image from a remote server. The present invention may serve to enhance banner advertisements which appear on a web page so as to remind users which company is sponsoring the particular page being viewed and to draw the user's attention to the banner advertisement. The present invention can also serve as a stand-alone branding vehicle as part of a “ubiquity campaign” to generate massive impressions among an audience of online users or can be simply used to make web sites more entertaining by providing animated, colorful cursors which may incorporate sound and/or animation, and which are configured so as to connote a relationship with the topic or subject of the web site. The foregoing sets forth certain objects, features and advantages provided by exemplary embodiments of the present invention. Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings arc designed solely for the purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. DETAILED DESCRIPTION OF THE DRAWINGS In the drawings in which like reference characters denote similar elements throughout the several views: FIG. 1 illustrates a diagrammatic representation of a computer network illustrating the interconnection of a plurality of computers in which the present invention is implemented; FIG. 2 illustrates a client-server computer network supporting the hardware and software of the present invention; FIG. 3 illustrates a flowchart diagram of an exemplary method of the present invention for obtaining information from a remote site for modifying a cursor image and implementing such information at numerous user sites; FIG. 4 illustrates a portion of the Cursor Display Instructions which is referenced as a resource within an HTML document according to one embodiment of the present invention; FIG. 5 illustrates a set of exemplary codes that cause the user terminal's cursor to be modified, then revert to its original shape in accordance with one embodiment of the present invention; FIG. 6 illustrates a plurality of user interface attributes that may be remotely modified in accordance with one embodiment of the present invention; and FIGS. 7-9 illustrate the appearance of a cursor prior to, during and after linking to a web page that contains cursor display instructions. DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT FIG. 1 illustrates a computer network, such as Internet 10, based on the client-server model. Internet 10 comprises a worldwide network of computers known as “servers” 12 which are accessible by “client computers” or “user terminals” 14, which are typically used by individual users or comprise a collection of personal computers interconnected via a Local Area Network or LAN, which are capable of accessing the Internet via a private Internet service or access provider (ISP) 16, such as the AT&T Worldnet Service® or the IBM Global Network®, or via an online service provider 18, such as America Online®, Compuserve®, the Microsoft Network® or Prodigy® (to name the most popular online service providers). One of the most common applications of the Internet is to support the World Wide Web (“WWW” or “the web”), which is a collection of servers on the Internet that utilize the Hypertext Transfer Protocol (HTTP), a known application protocol that facilitates data exchange between client and server and provides users or clients 14 access to files which can include text, graphics, sound, video, etc., using a standard page description language referred to as Hypertext Markup Language (HTML). Each client computer 14 as indicated in FIG. 1, includes a “web browser” or browser loaded on the client computer's hard drive 21. A browser is a common software tool which allows graphical user interface (GUI)-based access to Internet network servers 12 through Internet Service Providers, ISPs, 16 or online service providers 18. A server 12 functions as a so-called “web site” which supports and maintains a plurality of files in the form of documents and pages. A Uniform Resource Locator or URL identifies a specific network path to a server 12 or some resource located on that server which has a known syntax for defining the network connection. The fundamental intrinsic capabilities of the browser are: (1) the ability to communicate with other computers using HTTP, and (2) the ability to process and present HTML documents to the user via a graphical user interface, GUI. Recent versions of most browsers provide a plethora of other features beyond these two capabilities. For example, to increase its flexibility, the browser's intrinsic capabilities may be further extended through the use of software components, often called “controls” or “plug-ins”. While the intrinsic capabilities of the browser are linked at compile-time (“statically”), the code which implements the capabilities of the control or plug-in component is linked with the browser's code at run-time (“dynamically”). By supporting these components through standard interface definitions, the browser's capabilities can be extended in ways never anticipated by its original manufacturer. Another type of flexibility is offered when the browser implements some sort of command interpreter which is capable of interpreting and executing a code stream at run-time. In this case, the browser acts as a sort of “virtual machine” whose run-time behavior is completely governed by the code stream which it processes. The total scope of capabilities which can be realized with this approach is defined by the set of operations supported by the command interpreter. Individually and collectively, these mechanisms provide a powerful and flexible platform which supports a wide range of Internet-based applications. Currently, some of the emerging standards govern the operation of these mechanisms, although the invention is not limited in scope in that respect. For example, Microsoft has created an interface definition for Windows “dynamic link libraries” and for ActiveX software components. Sun Microsystems has defined a software component model called JavaBeans. Sun has also created a virtual machine architecture and language called Java, which is supported via a variety of commercially available compilers. While a Java compiler translates source code into pseudo-code output called an “applet”, which is in turn processed by the Java virtual machine, Microsoft, Sun, and others have also defined a set of HTML scripting languages whose source code is embedded directly in an HTML page. Microsoft's VBScript, JScript and Sun's JavaScript are examples of these embedded scripting languages. The standard web page description language, HTML, provides basic document formatting and permits the web site developer to create and specify “links” or “hyperlinks” to other servers and files. Obtaining a web page or connecting to a web site requires the specification of a URL using an HTML-compliant client browser. After specifying the URL, client computer 14 initiates a request to server 12 identified in the link and connects to the web site and receives a web page. The request by client computer 14 to server 12 via the link is advantageously communicated via a TCP/IP (Transfer Control Protocol/Internet Protocol) communication, although the invention is not limited in this respect and other network connections or Internet protocols may be used. Although an exemplary embodiment of the present invention is described based on the arrangement illustrated in FIG. 1, it is noted that the invention is not limited in scope in that arrangement and other types of system connections may be employed. For example, a plurality of user terminals may be connected to an online provider via dedicated communication channels, such as telephone lines. In accordance with this embodiment, the server system provides certain information that causes the cursor image on the video monitor of the user terminal to display an image as specified by the server system. As a result, the server system remotely defines and manages the shape and appearance of the cursor image in accordance with a pre-specified condition. The shape and appearance of the cursor image may correspond to the actual content of the data being provided to the user. Furthermore, regardless of the actual content of the data being provided to the user, the shape and appearance of the cursor image may be specified by the server system such that a plurality of user terminals at a desired point in time receive appropriate instructions to display the specified cursor image. FIG. 2 provides a block diagram of hardware and software which is representative of a client-server network system connected via the Internet according to one embodiment of the present invention. The user or client computer or user terminal 14 typically includes a number of hardware components and software subsystems which cooperate to deliver the wide range of capabilities demanded by a modem computer application or program. These include not only the basic computational processor 23 and memory 20, but also a variety of input and output devices such as the keyboard (not shown), mouse 22, video display monitor 24, audio speakers 26, non-volatile storage such as a hard drive 21 and network communications systems 46 such as a modem among other devices. User terminal 14 is controlled via an operating system (“OS”) 28 which serves to organize all the disparate elements within the computer 14 and expose them in a consistent and organized way to a program which may need some or all of these capabilities. The interface between a program, which is generally loaded within the computer's memory 20, and the systems under the control of the operating system 28 is commonly referred to as the Application Programming Interface (“API”) 30, which is essentially a library of functions which the program (“application”) can invoke when it needs to interact with any of these hardware subsystems. As illustrated, user terminal 14 contains a browser 32 loaded within the computer's memory 20, and is adapted to communicate with a browser extension or browser plug-in 34, both which are adapted to communicate with the operating system 28 via the application programming interface API 30. As illustrated, operating system 28 is supplemented by a set of “drivers” which control and provide the operating system 28 with access to peripheral devices which are a part of user terminal 14. The drivers include display driver 36 which controls and provides the operating system 28 with access to the cursor image or pointer 44 projected on video display monitor 24, a mouse driver 38 which controls and provides the operating system 28 with access to mouse 22, an audio driver 40 which controls and provides the operating system 28 with access to speakers 26. Operating system 28 is configured to provide animated images to the video monitor. Furthermore, in accordance with another embodiment of the invention, the display driver may be configured to provide animated images to the video monitor. Operating system 28 also provides access to a communication port 46 such as a modem which serves as a communication interface to the Internet 10. With continued reference to FIG. 2, user terminal 14 is connected to Internet 10 via a modem or some other communication interface such that information may be transmitted between user terminal 14 and Internet 10 via communication lines such as telephone cables or fiber optic networks, among other types of transmission systems. Internet 10 is also connected to numerous network servers, such as a simplified representation of a WWW server which is indicated as 48. Server 48 is provided with memory 50 into which the contents of certain data files are loaded. Such data files, among others, include Cursor Display Code 52, Cursor Information 54, and an HTML page containing Cursor Display Instructions 56, all of which are discussed in greater detail herein below. As illustrated in FIG. 2, these data files 52, 54, 56 are shown residing on the same server computer. However, the interconnected nature of the WWW allows these data files 52, 54, 56 to exist anywhere on Internet 10 For example, files 52 containing cursor display codes may be stored in various server systems, while files 54 containing cursor information may be stored in the same or other server systems, and files 56 containing HTML pages containing cursor display instructions may be stored in the same or yet other server systems. In operation, WWW server 48 includes software which recognizes file requests received from WWW clients or users by communication port 58 and fulfills these requests by retrieving data stored in data files, i.e., Cursor Display Code 52, Cursor Information 54, and an HTML page containing Cursor Display Instructions 56. One of the characteristics of most recent software systems is the graphically oriented user interface (GUI) which is viewable on video monitor 24. This graphical user interface helps to organize and filter the vast quantities of information which is accessible in a user terminal 14. Fundamental to the graphical user interface is the pointing device, generally mouse 22 which allows the user to manipulate or input information into the user terminal 14. Movement of mouse 22 is monitored by user terminal 14 which translates this movement into a corresponding movement of cursor 44 viewable on video monitor 24. As such, operating system 28 may expose, as some subset of its API 30, a set of functions which can be used to control aspects of the behavior and/or appearance of cursor 44. By combining the capabilities of browser extensions, such as indicated by 34 in FIG. 2, with the capabilities to modify cursor 44, it is possible for a WWW server, such as that indicated by 48 in FIG. 2, to control the display characteristics of cursor 44 displayed on video monitor 24 of the user's computer 14. By doing so, a cursor control arrangement is established which is capable of delivering information which supplements, enhances, or is completely independent of, other information transmitted from a server, such as indicated by 48, through traditional means as via a communications port 58. The basic conceptual components of such exemplary system for modifying cursor 44 comprises Cursor Display Code 52, Cursor Information 54, and Cursor Display Instructions 56, discussed hereinabove with reference to FIG. 2. Preferably, Cursor Display Code 52 comprises a set of instructions which are executed on the user terminal 14 and which interact directly with application programming interface 30 of the user terminal 14 and operating system 28 so as to accomplish the actual change of cursor 44. Cursor Information 54 is, advantageously, a set of data which identifies tile actual cursor image or images and corresponding audio content if desired. In one embodiment of the invention, Cursor Display Instruction 56 includes data that convey information that is used by Cursor Display Code 52 to control drivers, such as 36, 40, 46, and to identify such things, which among others consist of: the physical location of Cursor Information 54, the format of its representation, the intended manner and duration of its display, and information pertaining to how (and for how long) any cached Cursor Information 54 should be stored. In general, the fundamental elements of the process of changing cursor 44 displayed on video monitor 24 of user terminal 14 are as follows: Cursor Display Instructions 56 are initially embedded inside an HTML document, e.g. a web page. When browser 32 of the user terminal 14 encounters Cursor Display Instructions 56, Cursor Display Code 52 is retrieved then invoked. As part of the invocation, the browser passes to the Cursor Display Code coded information sufficient to specify the manner of the display. Cursor Display Code 52 then retrieves Cursor Information 54 either from within memory 20 of user terminal 14 or from storage at a remote site and then causes the Cursor Information to interact with the display system, such as display driver 36, of user terminal 14 via the application programming interface 30 of operating system 28. This interaction causes Cursor Information 54 to be accessed by the display driver 36 in order to accomplish the intended effect, e.g., the change or transformation of cursor 44 visible on video monitor 24, and a corresponding sound information may be heard on speakers 26. FIG. 4 illustrates the Cursor Display Instruction as a resource within an HTML document which is retrieved from a remote server. The Cursor Display Instructions as shown in FIG. 4 are written for ActiveX® technology, although the invention is not limited in scope to that technology. Among the information included within this resource definition is an identifier of the Cursor Display Code (the ActiveX® control), and the ActiveX® control's physical location on the Internet. This information is listed in lines 202-205 which generally identifies the Cursor Display Code. Line 204 of the Cursor Display Instruction is an identifier which comprises a globally unique name, often called a “Class ID”, and which allows a particular ActiveX® control to be distinguished from all other ActiveX® controls, such that the wrong ActiveX® control is prevented from being utilized or retrieved. The remainder of the Cursor Display Instruction listed in lines 206-224 include the ActiveX® parameters or argument list as discussed hereinafter with reference to FIG. 3. The argument list includes parameters which provide information such as the type of cursor image (line 206), where the image can be retrieved from if not already resident on the user computer (line 207), where usage statistics are to be transmitted to (line 208), how long a changed image should remain before reverting, if at all, to the initial image (line 209), whether the cursor image is cached in the user terminal (line 210), whether the transmitting server is authorized to send cursor display instructions (line 211), the dormant delay duration (line 212), the URL of a file which specifies cursor trajectory path (line 213), the URL of a file which specifies how the cursor's shape should change based on its location on the screen (line 214), the URL of a file which specifies how the cursor's shape should change based on its velocity (line 215), the URL of a file which specifies how the cursor's shape should change based on modifications to the mouse button or keyboard state (line 217), specification of the type of modification intended (line 218), specification of the priority of intended modification (line 219), specification that the modifications will occur as a result of the transfer of a series of data files (line 220), the URL of a file which specifies the display of a satellite image that tracks the movement of the cursor image (line 221-223), and location of additional display instructions (line 224). It is noted that the invention is not limited in scope in this respect and other features may be included in the Cursor Display Instructions data. One embodiment of this method in accordance with the present invention is set forth in greater detail in the flowchart illustrated in FIG. 3. This embodiment is discussed with reference to the use of ActiveX® technology currently promoted by the Microsoft Corp. The ActiveX® technology provides a mechanism for defining the format of Cursor Display Instructions 56, for defining, identifying, and in some instances dynamically retrieving Cursor Display Code 52, and for implementing the interaction between Cursor Display Instructions 56 and the Cursor Display Code 52 as previously described. Although the flowchart in FIG. 3 is discussed with reference to ActiveX® technology, the invention is not limited in this respect, and other technologies for use with browser extensions or “plug-ins” may be utilized in accordance with various embodiments of the present invention as illustrated in FIG. 3. Furthermore, additional embodiments in accordance with the principles of the present invention may be incorporated within other application software employed in the user terminal. For example, the operating system or the browser itself may be configured to incorporate the mechanism for receiving and recognizing the Cursor Display Instructions and in return provide additional instructions for changing the image or appearance of the cursor display. With reference to FIG. 3, in step 102, browser 32 of user terminal 14 retrieves an HTML file containing Cursor Display Instructions 56 The HTML file is retrieved when the user directs browser 32 to a remote WWW server site (such as, for example server 48 as indicated in FIG. 2) by specifying the uniform resource locator, URL, of the site on the Internet where the HTML file is located. When the HTML file is retrieved, it is loaded from the remote WWW server site at which point browser 32 of user terminal 14 begins its routine parsing of the HTML document and eventually encounters a reference to an ActiveX® control or some other information coded in an appropriate programming language such as Sun Microsystem Inc.'s Java® or VBScript®, which is embedded in the Cursor Display Instructions 56 within the HTML document. The Cursor Display Code is capable of interacting with tile application programming interface 30 of operating system 28 for the purpose of performing the change, transformation or “swap” of cursor 44 as it is presently displayed on video monitor 24. Upon encountering Cursor Display Instructions 56, browser 32 recognizes Cursor Display Instructions 56 as a request to invoke the particular ActiveX® control with a particular argument list or set of parameters as illustrated in FIG. 4. At step 104, browser 32 examines Cursor Display Instructions 56 and uses a unique class identification within the Cursor Display Instructions 56 to determine whether Cursor Display Code 52 (ActiveX® control) is already resident within local memory 20 of user computer 14. If the Cursor Display Code 52 is not resident in local memory 14, generally in the form of a browser extension or plug-in 34, or if local memory contains an obsolete version of Cursor Display Code 52, browser 32 attempts, at step 106, to retrieve the ActiveX® control from a remote server on the Internet and store the Cursor Display Code in local memory 20 of user terminal 14 at step 108. With reference to FIG. 4, these steps correspond to lines 202-205. Cursor Display Code 52 retrieved in step 106 may be client-platform specific and may also be browser specific such that browser 32 may transmit specific details to the remote server so that the remote server can deliver the appropriate Cursor Display Code 52. In accordance with another embodiment of the invention, browser extension or plug-in 34 may be configured such that it can recognize Cursor Display Instructions based on any one of the available technologies, such as Active X, JavaBeans, JavaScript or VBScript. Furthermore, it is understood that data compression techniques may be used in order to reduce the amount of network traffic involved in the transmission of data over the Internet. After Cursor Display Code 52 has been recognized by user terminal 14 as at step 104 or retrieved and loaded therein at steps 106 and 108, operating system 28 is queried to determine the current cursor display configuration and this information is temporarily cached in local memory 20 of user terminal 14 at step 110 so that the cursor configuration may eventually be restored to its original state. Before any changes are made to cursor 44, the system at step 111 determines whether server 48 is authorized to change cursor 44. If authorization is not confirmed, no changes to cursor 44 transpire. Step 112 is the first step which is executed from within the code of the ActiveX® control. At step 112, the ActiveX® control determines whether the image specified (Cursor Information 54) in the ActiveX® argument list which is to become the new cursor image exists in local memory 20 of user terminal 14. If the specified image in the ActiveX® argument list exists in local memory 20, it is retrieved therefrom at step 114. An additional argument in the ActiveX® argument list (line 207) identifies the location of this data on a remote server. If the specified image does not exist in local memory 20, this data is utilized by the ActiveX® control to retrieve Cursor Information 54 at step 116 from the specified location. At step 118, an additional argument added within the ActiveX® control can be used to determine whether and for how long Cursor Information 54 should be cached in local memory 20. At step 120 Cursor Information 54 is cached in local memory 20. At step 122, the cursor is caused to change in the manner consistent with the retrieved Cursor Display Instructions 56. In an alternative embodiment, an additional step may be included which provides the user with the option of saving and storing the retrieved Cursor Information 54 in the computer's permanent memory on hard drive 21 even after the retrieved cursor is displayed. Storing the retrieved Cursor Information 54 in the computer's permanent memory saves time on the next occasion when the user loads a web page which requires the same cursor since the cursor is already stored within the computer's memory and need not be retrieved from a remote server. Cursor Display Instructions 56 cause the invocation of an operating system function which causes the cursor to be displayed on video monitor 24. More specifically, the ActiveX® control invokes the application programming interface 30 of operating system 28 which causes the cursor image displayed on video monitor 24 to change to the form intended as recited in the argument list. The changed cursor is not limited to image. and may also include animation as well as sound. It should also be appreciated that most computers utilize a multitude of cursor images depending upon the application and task which is being run on the computer. The invention is not limited to changing only a single cursor image and any and all cursor images controlled by the computer's display driver 36 may be caused to change. At step 124 the ActiveX® control may send usage information to a particular remote server as coded in Cursor Display Instruction 56 or Cursor Display Code 52. This information can be used to calculate the usage statistics of particular cursor images or cursor information and the context in which they are retrieved and viewed by users. In this particular embodiment, this information is conveyed as a data file transmitted to the remote server via HTTP. The invention is not, however, limited in the type of information and/or statistics which may be transmitted to the server, nor is the invention limited to being conveyed via HTTP as those skilled in the art will understand that such information may be conveyed via other transfer protocols. With reference to FIG. 4, this step corresponds to line 208. Additionally, the information may contain an identifying code for the server which issued the web page which contained the Cursor Display Instructions. This information could be used, for example, to verify that the issuing server has been granted the appropriate license to use the technology, by comparing a list of authorized servers or through digital signature validation. In accordance with one embodiment of the present invention, the licensing arrangement is described in more detail, hereinafter. It is noted that licensing enforcement of the cursor display technology could be accomplished in several ways, and the invention is not limited in scope in that respect. As discussed previously, the server that transmits a web page may include the identity of the server in the form of a server ID within the Cursor Display Instructions. The user terminal then transmits the server ID to another server that among other things functions as a licensing body (“Licensing Body”) so as to authenticate the server that transmits the web page as a valid licensee. Should this authentication fail, the execution of Cursor Display Instructions may not occur. In an alternative implementation, the execution of Cursor Display Instructions may be allowed to execute even if the issuer fails authentication. Such an infraction could be logged by the Licensing Body for use in enforcement through traditional channels. For performance reasons it may be desirable to collect the usage information for a plurality of Cursor Display Instructions as the user accesses multiple servers, and transmit the collection of information in batch form to the Licensing Body. An alternative embodiment would involve the inclusion of an encrypted authentication code within the Cursor Display Instructions, as illustrated in line 211 of FIG. 4, or via a separate exchange of data between the client and server. In order to ensure that this code could not be re-used by other, non-authorized sites, it could for example be derived from the server's IP address, the date and time at which it is generated, the argument list, or some other information that is accessible to the client. Another possibility would involve the transmission of a unique or pseudo-unique code, from the client to the server. Upon receipt of this authentication code, the client would perform a decryption and verify its authenticity. Under such circumstances, the server software could be augmented with an Authentication Code Module supplied by the Licensing Body which generates and encrypts this code. The mechanism by which this augmentation could occur is similar to that discussed previously in the context of extending the client browser. For example, the server software could be modified and statically linked to the Authentication Code. Alternatively, it could be dynamically linked at run-time. Another alternative would be to implement the Authentication Code as its own process on the server and facilitate an inter-process communication protocol such as the Common Gateway Interface (“CGI”). At step 126, an ActiveX® control argument is used to determine whether the changed cursor should revert to its initial configuration. If it is intended to revert the changed cursor to its initial configuration, the reversion is paused at step 128 for a specified time period. After it is determined at step 130 that the specified time period has lapsed, the changed cursor reverts to its original configuration at step 132. Whether the cursor is caused to revert to its initial configuration is of concern to many users so as to ensure that the user's computer configuration is not permanently altered as a result of the process of changing the cursor. As such, additional alternative measures may be added into Cursor Display Instructions 54 such that the changed cursor could be restored to its original configuration when the ActiveX® control is loaded or unloaded, when the computer starts up, is rebooted or is shut down, when the browser is activated or shut down, when an animated cursor completes its animation sequence, when instructed by a remote server, or as a result of some user input such as setting an option in the browser or accessing another web page or site. An alternative to adding parameters to the Cursor Display Instructions would be to control the process of changing the cursor to its initial state by a control program downloaded by and executed on the client computer. An example written in VBScript and interacting with an ActiveX® control is included in FIG. 5. Additionally, one of the significant attributes of this embodiment is the manner in which Cursor Display Code 52 is retrieved from a remote server if it is not located in the computer's local memory. Since Cursor Display Code 52 may be operating system or browser specific, it may be necessary that the server with which the user computer 14 is communicating be informed by user terminal 14 of the specific type of Cursor Display Code 52 which is desired. In another embodiment of the invention, browser extension or plug-in 34 may be configured such that it can recognize Cursor Display Instructions based on any available technology such as ActiveX® and JavaScript . The operation of steps 102-132 as set forth in FIG. 3, may be illustrated pictorially in FIGS. 7-9. FIG. 7 illustrates an example of a typical web page 60 as it would appear on a user's video monitor 24 having the standard arrow cursor 44. In FIG. 8, there is illustrated a different web page 60a having a banner advertisement 62 for Fizzy Cola which contains Cursor Display Instructions. When web page 60a loads, the Cursor Display Instructions cause arrow cursor 44 to change into a Fizzy cola bottle shaped cursor 44a in conjunction with the Fizzy Cola banner advertisement. As illustrated in FIG. 9, if the user then loads a new web page 60b which is not provided with Cursor Display Instructions, the cola bottle shaped cursor of FIG. 8, reverts to the standard arrow cursor 44. It is also understood that ActiveX® is but one of numerous technologies utilized over the Internet with which a user's computer may interact in bringing about the change or transformation of the cursor displayed on video monitor 24. Other implementations may utilize different technologies such as Windows dynamic link libraries, VBScript and JScript from Microsoft, as well as Java, JavaScript and JavaBeans from Sun Microsystems Inc. While these examples represent the dominant standards-based definitions, proprietary implementations could also be developed. Accordingly, while ActiveX® represents one embodiment of distributing and invoking Cursor Display Information 54 on a user's computer 14, it is to be appreciated that there are a variety of alternative implementations, and this particular implementation should not be considered a limitation of the invention. For example, alternative versions of browser 32 may encapsulate the appropriate operating system application programming interface call within their own code modules such that a browser extension 34 is not required. In yet another embodiment of the invention the tasks described in steps 102 through 132 may be employed cooperatively between browser and browser extension or plug-in 34. Furthermore, browser 32 may employ a computational or processing engine such as an interpreter (as is the case with the Java® programming language, for example) which can extend the capabilities of browser 32 to a virtually unlimited degree. It is also to be understood that in the course of carrying out the process of changing the cursor as discussed hereinabove, user terminal 14 may communicate with a multitude of remote servers as opposed to just a single server. For example, Cursor Display Codes may be retrieved from one remote server, Cursor Instructions may be retrieved from a second remote server, and the user terminal 14 may also be in communication with a third server to which it is transmitting the usage statistics. Features identified in reference with FIG. 4 are described in more detail hereinafter. It is noted that in accordance with one embodiment of the invention, it may be desirable to modify the Cursor Display Code to improve its performance or enhance its capabilities. The server may transmit version information in the Cursor Display Instructions as illustrated in line 205 of FIG. 4. The Cursor Display Code could compare this information with its own version information in order to determine whether it has been rendered obsolete by a more recent version. If so, the Cursor Display Code could retrieve the current version from a remote server and invoke execution on the new version. In an alternative embodiment of the present invention the position, as well as the image, of the user terminal's cursor may be controlled by a remote server. This embodiment would be implemented within the Cursor Display Code 52 such that additional information could be passed to Cursor Display Code 52 via Cursor Display Instructions 56. The additional information passed to Cursor Display Code 52 would contain code Which indicates: (1) that the cursor position control is intended, (2) the conditions under which the cursor should be moved, and (3) the source of the data which specifies the particular movement that is intended. The latter could be stored in memory on a remote server and retrieved in a manner similar to retrieving Cursor Display Instructions 56 or the Cursor Display Code 52. For example, if no user input is received for a specified interval, the cursor image could change and the position of the cursor could be set such that it follows a specified trajectory for several seconds, then reverts to its original state as illustrated by line 213 of FIG. 4. In accordance with another embodiment of the invention it is possible to vary the modification to the cursor as a function of cursor position. For example, the cursor pointer could be controlled such that it “points” to a specific location on the screen regardless of the cursor's location on the screen as illustrated in line 214 of FIG. 4. In accordance with another embodiment of the invention it is possible to vary the modification to the cursor as a function of cursor velocity. For example tile cursor image could change from a stationary bird to a bird with flapping wings only when the cursor is moved quickly across the screen as illustrated in line 215 of FIG. 4. Furthermore, it is possible to vary the modification to the system-level user interface attributes as a function of mouse button state or keyboard state. For example, the image of a cube could be replaced with that of a jack-in-the-box when the mouse button is depressed. In accordance with another embodiment of the invention, it is possible to modify other “system-level” attributes of the client computer's user interface, hereafter called “system-level user interface attributes”. These attributes, as illustrated in FIG. 6 are typically under the control of the operating system and, as such, they exist independently of the user “applications” (programs) and data which are stored on the computer and interact with that operating system. User applications interact with the operating system to deliver the computer's functionality to the user Examples of user applications include word-processors, spreadsheets, web browsers, games, etc. The operating system may contribute certain user interface elements to the user interface of the applications running on it. Because many of these attributes are inherited from the operating system by all applications running on that operating system, applications tend to exhibit a degree of commonality in their user interfaces. Examples of these attributes include: the shape and color of the cursor 401, the shape and color of a status bar which displays current state information to the user 403, the shape and color of the scroll bar which indicates the relative position and scope of the displayed sub-image to that of the underlying larger image to the user 407, the shape and color of the title bar which displays current state information 409, the shape and color of icons representing standard window operations such as close, minimize display size, restore display size, etc. 411. Thus, these system level attributes may also be modified in response to Cursor Display Instructions data. In addition, the operating system itself may have a user interface. Examples include: the images and sounds displayed when the computer starts or shuts down, the background image (“wallpaper”) against which other graphical elements are displayed 413, file catalogs and file selection mechanisms 415, system icons 416, file invocation mechanisms 417, buttons 419, process selection mechanisms 421, etc. Further examples include the icons representing various system elements or information such as files 418, groups of files 420, files marked for deletion 422, as well as standard, information bearing “dialog boxes”, such as cancel, warning, illegal operation, stop, accept, continue, etc. 423. The system may also support a set of audibly distinct waveforms which may be used to convey similar information to the user. These operating system user interfaces may also be modified in response to a Cursor Display Instruction data. In yet another exemplary embodiment of the present invention a plurality of modifications to the system-level user interface attributes may occur simultaneously. For example, the cursor could animate while an audio waveform is playing, as the minimize display icon changes to a specific image. A further feature of the invention is to accumulate information regarding the user's exposure time to various system-level user interface attribute modifications, and to vary the exposure to those modifications accordingly. For example, the client could transmit exposure data to the server and the server would select a version of the image based on that data. Furthermore, the exposure data could be transmitted as part of the usage statistics discussed previously. Another feature of the invention is to monitor the load being placed on the client system by the user and schedule data exchange with the servers so that it occurs when it is least disruptive to the user's activities. It is also possible to allow the user to control the level of interface modification he or she wishes to entertain. For example, the user could specify that only those modifications of specific types, as illustrated on line 218 of FIG. 4 or of specific priority should be delivered, or even that none be delivered, as illustrated at lines 218 and 219 of FIG. 4. This specification could be implemented directly by the user on the client system, or could be implemented through communication with a remote server. In accordance with another embodiment of the invention it is possible to transmit the image and/or audio data which specifies the modification as a series of data files which are delivered in a continuous stream to the client, as illustrated at line 220 of FIG. 4. These files are exposed to the user before the complete set of data has been delivered, thereby providing the capability for the initiation of long animations or audio files before the entire quantity of data has been received by the client. A further feature of the invention is to support the display of a “satellite” image which tracks the cursor's position on the screen. For example, the cursor image could be replaced with that of a mouse, and the image of a cat could be displayed near that mouse. When the cursor is moved, the satellite image moves accordingly at a specific offset, as illustrated at lines 221-223 of FIG. 4. A further feature of the invention is to provide a mechanism for the user to quickly establish a connection with a specific server based on the specific user interface attribute modification which is in effect when the mechanism is invoked. For example, the user could press a specific key sequence on the keyboard and immediately jump to the web site related to the cursor image which is currently displayed. In accordance with another embodiment of the invention, it is possible to convey additional detailed Cursor Display Instructions as a separate file which is explicitly retrieved from a server by the Cursor Display Code, as illustrated at line 224 of FIG. 4. For each modification to the system-level user interface attributes, an appropriate set of display instructions must be transmitted to the client. These could take the form of additional parameters in the Cursor Display Instructions as discussed previously, or they could be represented within a code module which is received by and executed on the client. As discussed previously, Java, and its related technologies could be used for such a purpose, but use of these technologies should not considered a limitation of the invention. It is noted that there are numerous ways in which a system-level user interface attribute modification is accomplished in accordance with the principles of the present invention. It is further noted that system level user interface attributes may be modified independently or in conjunction with cursor modification. Furthermore, the system-level user interface attribute modification may be related to specific information displayed on the rest of the user's screen (hereafter referred to as “specific information”) in many different ways. Thus, the present invention is not limited in scope to how content providers may relate the system-level user interface attribute with the specific information. Rather, at least one of the goals of the present invention is to enable the content providers to modify the system-level user interface attribute whenever and wherever they see fit. For example, content providers may modify system-level user interface attributes at a remote user's terminal for advertising, entertainment, information delivery, celebrating an event, or other reasons, and therefore, the invention is not limited in scope in that respect. Furthermore, when a content provider elects to display a specified system-level user interface attribute in conjunction with and corresponding to specific information conveyed via the user's terminal, the cursor image and the background display data are deemed related. Additional examples intended to illustrate some applications of the present invention are explained below, although the invention is not limited in scope to any one of these examples. Thus, in accordance with one embodiment of the invention, a modified cursor might take the appearance of a “Fizzy Cola” bottle when a “Fizzy Cola” banner advertisement appears among the display data of a popular search engine's site. Similarly, the cursor can be modified for advertising purposes to represent Fizzy Cola's logo, its corporate mascot, images of its products or services, slogans, icons, brand images, advertising messages (the word “Thirsty?”, for example), abstract suggestions (such as a straw or glass), etc. Alternatively, Fizzy Cola, on its own site, or homepage, might have a picture of a bottle of Fizzy in the middle of the page (in the display data). A dynamic cursor image could then be used to show a person holding a straw in such a way that the straw always points from the user toward the top of the Fizzy bottle, no matter where the cursor moves on the screen. The straw, in this case, might be “attached” to the cursor image (part of the same image) or could be separate, “satellite” image, a “sprite,” whose movement on the screen (in this case) is related to the movement of the cursor. Sprites, which can appear and disappear as desired, can enhance the invention by enabling the use of graphical elements which are associated with the cursor but which reside outside the limited cursor “space” (which in some systems may be, at maximum, 32 by 32 pixels). For the purposes of the invention, however, there should be no limitation to the size of the cursor. Additional examples of modification to the cursor include rendering the cursor as a baseball bat (on a site with sports information), a pink but otherwise standard-shaped pointer (on a site about the Pink Panther), a witch-on-a-stick to celebrate Halloween, the Statue of Liberty to celebrate the Fourth of July, etc. All of the foregoing cursor images could be enhanced with related animations, such as the bat hitting the ball. Similarly, the present invention can be used to replace not just the standard arrow but other standard cursors as well, such as the generic hand with pointing index finger (the icon commonly used in browsers to indicate that the pointer is positioned above a hot link). A site for children might, for example, replace this generic pointing-hand cursor with the pointing “paw” of a furry animal. A site dealing with horror movies might choose to replace this pointing hand with a bony skeleton-like hand. Additional examples involve cursors with text or numbers. For example, the cursor might contain the text “Right-Click Now!” prompting users to click the right button of their mouse (where right-clicking on the mouse could, for example, trigger the delivery of a new page of display data). It may also be desirable in certain cases to put alphanumeric data in the cursor “space” to convey information to users, such as stock prices, baseball game scores, the temperature in Florida, etc. The data can be static, semi-static (i.e. updated periodically), or dynamic (updated frequently—possibly incorporating available streaming-data and data-compression technologies). Use of associated sound, sprites, animations, and modified system display elements are provided as enhancements to the basic invention. For example, a Fizzy cola mascot could appear in the cursor space in conjunction with the speakers, attached to the user's machine, playing the sound of the mascot saying, “drink Fizzy!” Any time a content provider elects to incorporate said enhancements in conjunction with a new modified cursor image, the cursor image and said enhancements have been deemed related. The present invention allows users to change cursor images, it also allows them to change them back. It may be desirable to revert the pointer to a previous or generic pointer image. Given the Fizzy Cola example above, if the page containing display data changes and there is no longer an advertisement for Fizzy, but rather an advertisement for its rival, Jazzy Cola, it may be desirable to ensure the removal of the Fizzy cursor image(s) and accompanying enhancements. The foregoing examples are not intended to suggest limited uses for this invention; to the contrary, the examples are intended to illustrate the wide range of uses for this invention. The collective creativity of the online advertising, art, design, commerce, content publishing, and related industries will develop many novel and unforeseen ways to use the present invention. The versatility of the present invention should not be regarded as a limitation on its scope. Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. It is to be understood that the drawings are not necessarily drawn to scale, but that they are merely conceptual in nature. | <SOH> BACKGROUND OF THE INVENTION <EOH>The World Wide Web (“WWW” or “web”) and online services such as America Online, in conjunction with faster and more powerful personal computers, have rendered the Internet and other interactive online computer networks accessible to millions of people all over the world. Concomitant with the emergence of this new communication medium, digital content providers have proliferated, providing online news, entertainment, games and all sorts of other content. As with other mass mediums, such as television, radio, and print publications, the entities that create such content seek to offset their expenses by selling advertising. With reference to the WWW, online advertising has become a multimillion dollar business, to the amount of approximately $300 million dollars in 1996. The most common type of online advertisement exists in the form of “banner advertisements”. Users of online services routinely encounter banner ads on the top, sides, and/or bottom of their video monitor screens when viewing a web page. Banner ads are generally square or rectangular boxes provided with some combination of graphics, color and text directed to the product or service being advertised. As such, the intention of these banner advertisements is to create impressions among online users and to convey some advertising message and/or logo Banner ads are usually provided on a web page in the form of a “hyperlink”, in which users who yield to the advertisement's solicitation to “Click Here” are transported to the web site of the manufacturer of the product or service being advertised, or to some other screen which provides additional information about the product or service. Unfortunately, banner ads occupy only a small portion of a web page. As the user scrolls down a page the banner ad disappears. Although online advertisers and content publishers have attempted to optimize the visibility of banner advertisements by placing them on a popular web page where they will have a greater chance of being seen, Internet users, nevertheless, can easily ignore or find ways to remove and eliminate from their view the banner ads which exist on the web pages they are viewing. As such, the banner ads are rendered ineffective in their aim to provide information about a product or service. Additionally, money spent to advertise a product may be wasted if users are able to ignore or remove the advertisements from the web pages they are viewing. Another method of online advertising involves the use of “frames” on a web page. Frames are a feature supported by the recent versions of leading web navigating programs known as browses, such as Netscape Navigator® and Microsoft's Internet Explorer ®. Frames generally divide up a user's screen so that the user can, for example, independently scroll down each of numerous frames which appear on the web page being viewed on the user's screen. Like banner advertisements, frames can be aesthetically unappealing as well as confusing to the user. Additionally, placement of advertising frames on a web page generally results in cramping or decreasing the size of the main content frame which oftentimes renders the content in the main frame difficult to read. As a result, users have developed ways to reduce the size or even eliminate frames from the web page being viewed. Another type of online advertising involves the self-appearing window which generally appears on its own as a user is using the Internet or browsing on the WWW. Such advertisements are relatively easy for a user to avoid as a user may simply re-size the window to make it smaller drag another window or object in front of it to obscure it from view, close the advertising window, or simply ignore it and continue with the task being undertaken online. Recently, online advertisers have begun using self-appearing screens which are delivered via dialog boxes which dominate the main part of the screen. Although these dialog boxes can be removed when the user clicks on the appropriate place(s) on the dialog box, the self-appearing dialog boxes have a much higher rate of being seen by users. This follows because the dialog boxes take control of the user's screen for a preset amount of time and/or until the user clicks on the appropriate place(s) to make the dialog box disappear. The recent prevalence in the use of self-appearing dialog box advertising has resulted in a more intrusive method of advertising which has resulted in resentment among users who are accustomed to more passive online advertising methods such as the frames and banner advertisements which are more easily avoided and/or ignored. Accordingly, there is a need for a simple means to deliver advertising elements, i.e. logos, animation's, sound, impressions, text, etc., without the annoyance of totally interrupting and intrusive content delivery, and without the passiveness of ordinary banner and frame advertisements which can be easily ignored. | <SOH> OBJECTS AND SUMMARY OF THE INVENTION <EOH>It is thus a general object of the present invention to provide a means for delivering online advertisements which are unintrusive and which are not easily ignored by a user. A more specific object of the present invention is to provide a server system for modifying a cursor image to a specific image displayed on a video monitor of a remote user's terminal. It is another object of the present invention to provide a server system for modifying a cursor image to a specific image displayed on a video monitor of a remote user's terminal for the purposes of providing on-screen advertising. It is a further object of the present invention to provide a means for providing on-screen advertising transmitted online which does not interrupt the delivery of content and which is aesthetically appealing and which affords the advertiser a great degree of unintrusive exposure. It is still a further object of the present invention to provide a system and a method for causing a remote user terminal to display a cursor image as specified by a server terminal. It is also an object of the present invention to provide a system and method for causing a remote user terminal to display a cursor image as specified by a server terminal, wherein the cursor image corresponds to the content retrieved by the user terminal. It is a further object of the present invention to provide a system and method for causing a remote user terminal to display a cursor image such as a corporate name or logo, a brand logo, an advertising or marketing icon or slogan, an animated advertising image, and a related audio clip, that relate to an advertisement, such as a banner advertisement, that is included in the information content being retrieved by the user terminal. It is an additional object of the present invention to provide a means for changing a cursor's appearance by sending data and control signals from a remote computer so that the cursor or pointer's appearance is associated with a portion of, or the entire content being displayed on the user's screen. It is still an additional object of the present invention to provide a means for changing the appearance of a computer's cursor or pointer by sending data and control signals from a remote computer so that the cursor or pointer's appearance is associated with advertising messages. These and other objects of the invention are realized in various embodiments of the present invention by providing a system for delivering advertising elements online without the annoyance resulting from the interruption of content delivery and without the passiveness of ordinary banner and frame advertisements which can be too easily ignored or bypassed or removed. An exemplary embodiment of the present invention is directed to a system that provides online advertising content using the on-screen cursor which is generally controlled by an input of positioning device known as a “mouse” or “mouse pointer”. Nearly all online computer interfaces utilize a wired or remote control positioning device such as a mouse or roller or track ball which controls the cursor's movement on the screen. It is the cursor controlled by the mouse or positioning device which a user uses to “navigate” or move the cursor over objects, buttons, menus, scroll bars, etc., which appear on-screen and then clicking or in some cases double-clicking in order to activate a screen or task, or to commence an application or some function. As a result of the prevalence of the use of the mouse, by many millions of users of online systems, a great deal of time is spent focused on the icons which represent the cursor or pointer as it may appear in some cases. Presently, pointer icons change from application to application and can also change within an application depending upon where on the screen the pointer is located, what state the computer exists in at a given moment, and what tools are being used, among other factors. Generally, pointers change shape to reflect an internal state of the computer or the present function within an application. While it is not new for pointers and cursors to change shape, pointers are not presently used to convey advertising. In conventional systems, the appearance of the cursor or pointer does not change to correspond with on-line content being displayed on the screen. The present invention provides a means for enabling cursors and pointers to change color, shape, appearance, make sounds, display animation, etc., when the user's terminal or computer, known as the “client” or “user” terminal, which has a network connection, receives certain instructions from a remote or “server” computer attached to the network. In an exemplary embodiment of the present invention, the generic cursor or pointer icons used in many networking applications, such as black arrows, hands with a pointing finger, spinning wheels, hourglasses, wristwatches, and others, will change appearance, and in some cases may incorporate sound or animation, in a way that is linked and related to the content, such as a web page, which is being transmitted to and displayed on the client computer. The cursor or pointer may appear as a corporate or a brand logo which relates to advertising content within the web page being transmitted and displayed. The cursor or pointer image may also appear in a specified shape or color that is intended to convey a message that relates to the advertising content within the web page being transmitted and displayed. An exemplary embodiment of the present invention comprises a combination of hardware and enabling software residing on the transmitting (server) computer or network server and/or on the receiving (client or user) computer or terminal which brings about the stated effect of enabling a computer's cursor or pointer to change appearance and in certain cases provide sound and animation which is linked and related to the content being transmitted to and displayed on the client computer or terminal. The transmitting computer and receiving computer or terminal advantageously include a processor, an operating system (OS) loaded thereon, a video monitor used to display a graphical user interface (GUI) and a Hypertext Transfer Protocol (HTTP) compliant web browser capable of loading and displaying hypertext documents transmitted over the Internet, although the invention is not limited in scope in that respect. For example, the receiving terminal may be any device that is able to communicate with a remote server, such as a user computer terminal, a user dumb terminal, or a television based system, such as Web TV® terminal and other devices. Preferably, coded information for bringing about the change in appearance of the cursor are embedded within the web page being loaded and viewed. In one embodiment of the present invention, the web page is written in Hypertext Markup Language (HTML) which is one of the most common standard page description languages used to develop web pages. Typically a web browser retrieves a web page to be loaded on user's terminal. The retrieved web page in accordance with one embodiment of the invention contains a set of predetermined instructions referred to herein as cursor display instructions. The browser or browser extension interprets the information contained in cursor display instructions and instructs the operating system of the user's terminal via an application programming interface (API) to check its memory to determine if the user terminal is capable of loading the coded image, animation, and/or soundbite. If the image, etc. has been previously cached in the client computer memory, the cursor display instructions instruct one or more of the many devices controlled by the operating system in the user's terminal, such as the video monitor and audio speakers to display the desired images, animation and play desired sounds. If the image, etc. has not been previously cached in the client computer's memory, the browser or browser extension retrieves the information corresponding to the desired image from a remote server. The present invention may serve to enhance banner advertisements which appear on a web page so as to remind users which company is sponsoring the particular page being viewed and to draw the user's attention to the banner advertisement. The present invention can also serve as a stand-alone branding vehicle as part of a “ubiquity campaign” to generate massive impressions among an audience of online users or can be simply used to make web sites more entertaining by providing animated, colorful cursors which may incorporate sound and/or animation, and which are configured so as to connote a relationship with the topic or subject of the web site. The foregoing sets forth certain objects, features and advantages provided by exemplary embodiments of the present invention. Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings arc designed solely for the purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. | 20050121 | 20110705 | 20050929 | 72088.0 | 2 | BONSHOCK, DENNIS G | SYSTEM FOR REPLACING A CURSOR IMAGE IN CONNECTION WITH DISPLAYING THE CONTENTS OF A WEB PAGE | SMALL | 0 | ACCEPTED | 2,005 |
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11,040,282 | ACCEPTED | MATING EXTENDER FOR ELECTRICALLY CONNECTING WITH TWO ELECTRICAL CONNECTORS | A mating extender electrically engages with a pair of complementary connectors. The mating extender comprises an insulative housing having first and second mating sections, and a number of wafers parallelly assembled into the insulative housing. Each wafer comprises an insulative frame and a plurality of contacts each formed by a pair of electrically stacked semi-contacts. Each contact has an intermediate portion retained in the insulative frame, a pair of first contact tails and a pair of second contact tails at opposite ends of the intermediate portion and received in the first and the second mating sections of the insulative housing, respectively. | 1. A mating extender comprising: an insulative housing having first and second mating ports; a plurality of parallel wafers retained in the insulative housing, each wafer comprising an insulative frame and a plurality of contacts each formed by a pair of stacked semi-contacts, each contact having an intermediate portion retained in the insulative frame, a pair of first contact tails and a pair of second contact tails at opposite ends of the intermediate portion, the first and second contact tails exposed into the first and the second mating ports, respectively, the first contact tails of the contact comprising a pair of partially overlapped contact portions. 2. The mating extender according to claim 1, wherein the first contact tails of the contact comprises a pair of partially overlapped contact portions. 3. The mating extender according to claim 1, wherein the insulative frame of the wafer defines a chamber in a center portion thereof. 4. The mating extender according to claim 1, wherein the first contact tail of the contact has an interface lying in a first plane, and wherein the wafer lies in a second plane perpendicular to the first plane. 5. The mating extender according to claim 4, wherein the wafers comprise a plurality of signal and shielding wafers alternatively arranged with each other. 6. The mating extender according to claim 5, wherein the contacts of the shielding wafers are electrically isolated one another. 7. The mating extender according to claim 6, wherein the intermediate portion of the contact of the shielding wafer is formed by two interlapped interims of the semi-contacts. 8. The mating extender according to claim 1, wherein the insulative housing comprises two housing halves. 9. The mating extender according to claim 8, wherein one housing half comprises a resilient latch at a side wall thereof and another housing half defines a receiving recess in an exterior face thereof receiving the resilient latch. 10. The mating extender according to claim 8, wherein each housing half defines a plurality of parallel slots receiving the wafers. 11. The mating extender according to claim 10, wherein the housing half defines a pair of guiding channels at opposite ends of the slots, and wherein the insulative frame of the wafer is formed with a pair of guiding flanges at opposite ends thereof for sliding into corresponding guiding channels. 12. The mating extender according to claim 11, wherein the housing half defines a plurality of columns of passageways receiving corresponding contact tails of the contacts, each column of passageways communicating with a corresponding slot. 13. A mating extender for use with two opposite connectors, comprising: an insulative housing including first and second halves commonly defining an enclosed cavity therebetween; and a plurality of wafers retained in said cavity in a parallel relation with one another, each wafer defining an insulative frame with a plurality of contacts thereon; wherein each of said contacts including an intermediate portion disposed in the cavity and opposite first and second mating portions extending in opposite direction away from each other and out of the corresponding halves to be exposed to an exterior for mating with the corresponding connectors, respectively. 14. The mating extender according to claim 13, wherein said first and second halves are similar to each other while assembled to each other in a mutually reversed manner. 15. An electrical assembly comprising: first and second connector oppositely arrange with each other in a spaced distance along a direction; an extender sandwiched between said first and second connectors in said first direction, the extender including: first and second halves similar to and assemble to each other and commonly defining a cavity therein; and a plurality of contacts disposed the cavity, each of the contacts including an intermediate section disposed in the cavity, and opposite first and second mating sections extending from two opposite ends of the intermediate section away from each other oppositely in said direction, and out of the corresponding first and second halves to mate with the corresponding first and second connectors, respectively. 16. The assembly according to claim 15, wherein said first and second mating sections are similar to each other and symmetrically arranged with each other relative to the intermediate section. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mating extender, and more particularly to a mating extender which is able to vary in height and is adapted for simultaneously and electrically connecting with a pair of headers respectively mounted on two printed circuit boards. 2. Description of Related Art U.S. Pat. No. 6,152,747 discloses an electrical connector assembly comprising a plug and a receptacle. The plug and the receptacle both comprise a number of parallel modules. Each module comprises an insulative support, a plurality of signal contacts attached on one side of the support and a shielding plate attached on another side of the support. Each signal contact comprises a tail having a solder ball attached thereon. The shielding plate is formed with a plurality of end portions each having a solder ball attached thereon. The solder balls on the signal contacts and the shielding plate lie in a common plane. The plug is adapted for being surface mounted onto a first printed circuit board with the solder balls soldered onto corresponding pads on the first printed circuit board. The receptacle is adapted for being surface mounted onto a second printed circuit board positioned parallelly to the first printed circuit board with the solder balls soldered onto corresponding pads on the second printed circuit board. In some applications, a large distance is required to be kept between the first and second printed circuit boards. Therefore, a high profile plug or receptacle is accordingly designed to satisfy this requirement. However, as the height of the plug or the receptacle increases, it becomes more difficult to surface solder the plug or the receptacle to the printed circuit boards. Hence, a mating extender between the plug and the receptacle is desired to overcome the disadvantage of the prior art. SUMMARY OF THE INVENTION An object of the present invention is to provide a mating extender for simultaneously and electrically connecting with a pair of headers respectively mounted on two parallel printed circuit boards to match different distances between the printed circuit boards. Another object of the present invention is to provide a mating extender comprising a plurality of contacts each having a redundant interface. To achieve the above object, an mating extender electrically engages with a pair of complementary connectors. The mating extender comprises an insulative housing having first and second mating sections, and a number of wafers parallelly assembled into the insulative housing. Each wafer comprises an insulative frame and a plurality of contacts each formed by a pair of electrically stacked semi-contacts. Each contact has an intermediate portion retained in the insulative frame, a pair of first contact tails and a pair of second contact tails at opposite ends of the intermediate portion and received in the first and the second mating sections of the insulative housing, respectively. Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a mating extender in accordance with the present invention; FIG. 2 is an assembled perspective view of the mating extender shown in FIG. 1; FIG. 3 is a perspective view of a cover half shown in FIG. 1 taken from another aspect; FIG. 4 is a perspective view of a header in accordance with the present invention; FIG. 5A is a perspective view of a differential signal wafer shown in FIG. 1; FIG. 5B is a perspective view of a metallic lead frame with a plurality of differential signal semi-contacts shown in FIG. 5A; FIG. 6A is a perspective view of a single-ended signal wafer shown in FIG. 1; FIG. 6B is a perspective view of a metallic lead frame with a plurality of single-ended signal semi-contacts shown in FIG. 6A; FIG. 7A is a perspective view of a shielding wafer shown in FIG. 1; FIG. 7B is a perspective view of a metallic lead frame with a plurality of grounding semi-contacts shown in FIG. 7A; FIG. 8A is a planar view schematically showing a differential signal wafer of FIG. 5A mating with a pair of headers of FIG. 4; FIG. 8B is a planar view schematically showing a single-ended signal wafer of FIG. 6A mating with the pair of headers shown in FIG. 4; and FIG. 8C is a planar view schematically showing a shielding wafer of FIG. 7A mating with the pair of headers shown in FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 8A-8C, a mating extender 1 in accordance with the present invention has a pair of opposite mating parts electrically and mechanically engaging with a pair of headers 8 (only one header shown in FIG. 4), respectively. One header 8 is generally adapted for being mounted onto a first Printed Circuit Board (PCB) (not shown) with a plurality of connector mounted thereon and another header 8 is adapted for mounting onto a second PCB (not shown) with a plurality of connector mounted thereon. Referring to FIGS. 1-3, the mating extender 1 comprises a box-shaped cover 10 including a pair of cover halves 11 engaging with each other. Each cover half 11 has a bottom wall 12, a pair of opposite side walls 13 extending from opposite sides of the bottom wall 12 and a pair of opposite end walls 14 extending from opposite ends of the bottom wall 12 and interconnecting with the side walls 13. A semi-receiving space 15 is defined between an inner face 120 of the bottom wall 12, the side walls 13 and the end walls 14. The semi-receiving spaces 15 of the two halves 11 of the cover 10 form a whole receiving space when the two halves 11 engage with each other. Accordingly, a mating port 16 is defined between a mating face 121 of the bottom wall 12 opposite to the inner face 120, the side walls 13 and the end walls 14. The bottom wall 12 defines a plurality of parallel slots 17 extending between the side walls 13 in the inner face 120 thereof and a plurality of columns of openings 18 in the mating face 121. The bottom wall 12 further defines a plurality of columns of holes 19 passing therethrough and each column of holes 19 is arranged along a direction parallel to the slots 17. Each column of openings 18 is communicated with a corresponding slot 17. A pair of opposite guiding channels 170 is provided on the side wall 13 at opposite ends of one of every two adjacent slots 17 and each columns of holes 19. One side wall 13 is formed with a projection 130 at an upper edge thereof and another side wall 13 defines a cutout 131 at an upper edge thereof. Each side wall 13 comprises a T-shaped resilient latch 132 upwardly projecting beyond the upper edge thereof, a T-shaped receiving recess 133 defined in an exterior face thereof and a lead-in 134 in the receiving recess 133. As best shown in FIG. 2, in assembly of the mating extender 1, the projection 130 of one cover half 11 is received in the cutout 131 of the other cover half 11. Accordingly, the resilient latch 132 of one cover half 11 is firstly deflected outwardly due to pressing of the lead-in 134 and then snap into the receiving recess 133 of the other cover half 11. The side wall 13 is formed with a pair of guide ribs 135 on the exterior face thereof. Referring to FIG. 1, the mating extender 1 comprises a plurality of differential signal wafers 20, single-ended signal wafers 30 and shielding wafers 40 received in the whole receiving space of the cover 10 with opposite ends of the wafers respectively retained in corresponding slots 17. Referring to FIG. 5A, each differential signal wafer 20 comprises an insulative frame 21 comprising a chamber 210 defined in a central portion thereof for saving material and improving electrical performance, and a pair of guiding flanges 211 at opposite side edges thereof. The guiding flanges 211 of the insulative frame 21 slide into the guiding channels 170 provided on the side wall 13 for guiding the differential signal wafer 20 correctly insertion. The differential signal wafer 20 further comprises a plurality of pairs of differential signal contacts 22 each pair formed by two pairs of differential signal semi-contacts 23 (FIG. 5B). Referring to FIG. 5B, a metallic lead frame 24 is provided with a plurality of differential signal semi-contacts 23. Two pieces of lead frames 24 are stacked with corresponding differential signal semi-contacts 23 entirely and electrically overlapped with each other to form the differential signal contacts 22. The stacked lead frames 24 are insert molded into the insulative frame 21. When assembled, tie bars 25 of the lead frame 24, which are connected between the adjacent differential signal semi-contacts 23, are cut away to provide electrically isolated differential signal contacts 22. Each differential signal contact 22 comprises two pairs of resilient contact tails 220 respectively at opposite ends thereof, and an elongated intermediate portion 221 between the two pairs of the contact tails 220 and partially exposed into the chamber 210. Each pair of contact tails 220 is formed with a pair of contacting portions 222 at a free end thereof and completely overlapped with each other. Each pair of contact tails 220 is exposed into the mating port 16 of the halves 11 of the cover 10 through one and the same hole 19, shown in FIG. 2. Referring to FIG. 6A, likewise, each single-end signal wafer 30 comprises an insulative frame 31 defining a chamber 310 in a central portion thereof and a pair of guiding flanges 311 at opposite side edges thereof. The guiding flanges 311 of the wafer 30 slide into the guiding channels 170 provided on the side wall 13 for guiding the single-ended signal wafer 30 correctly inserting into the slot 17. Referring to FIG. 6B and in conjunction with FIG. 6A, the single-ended signal wafer 30 further comprises a plurality of single-ended signal contacts 32 each formed by a pair of single-ended signal semi-contacts 33. A metallic lead frame 34 is provided with a plurality of single-ended signal semi-contacts 33. Two pieces of metal lead frames 34 are reversely stacked with corresponding single-ended signal semi-contacts 33 electrically and partially overlapped with each other to form the single-ended signal contacts 32. The stacked lead frames 34 are insert molded into the insulative frame 31. When assembled, tie bars 35 of the metal lead frame 34, which are connected between the adjacent single-ended signal semi-contacts 33, are cut away to provide electrically isolated single-ended signal contacts 32. Each single-ended signal contact 32 comprises two pairs of resilient contact tails 320 at opposite ends thereof respectively, and an intermediate portion 321 between the two pairs of contact tails 320. Each pair of contact tails 320 is exposed into the mating port 16 through one and the same opening 18 of the cover halves 11, shown in FIG. 2. Each pair of contact tails 320 has a pair of contact portions 322 partially overlapped with each other. Referring to FIGS. 7A-7B, each shielding wafer 40 is disposed between every two adjacent signal wafers 20, 30 for shielding purpose in the present embodiment. As everybody known, there may also be some other arrangement depending upon electrical performance requirements. Likewise, the shielding wafer 40 comprises an insulative frame 41 defining a chamber 410 in a central portion thereof and a plurality of grounding contacts 42 each formed by a pair of grounding semi-contacts 43. A metallic lead frame 44 is provided with a plurality of grounding semi-contacts 43. Two pieces of lead frames 44 are reversely stacked with corresponding grounding semi-contacts 43 electrically and partially overlapped each other to form the grounding contacts 42. The lead frames 44 are insert molded into the insulative frame 41. When assembled, tie bars 45 of the metal lead frame 44, which are connected between the adjacent grounding semi-contacts 43, are cut away to provide electrically isolated grounding contacts 42. Each grounding contact 42 comprises two pairs of resilient contact tails 420 respectively at opposite ends thereof, and an intermediate portion 421 between the two pairs of contact tails 420. Each pair of contact tails 420 is exposed into the mating port 16 through one and the same opening 18 of the cover halves 11, shown in FIG. 2. Each pair of contact tails 420 has a pair of contact portions 422 partially overlapped with each other. The intermediate portion 421 of the grounding contact 42 is formed by two interlapped interims of the grounding semi-contacts 43 and has a pair of stagger side edges 423, whereby the grounding contacts 42 not only establish a continuous shielding plane but also are electrically isolated from each other. Referring to FIGS. 4 and 8A-8C, the header 8 comprises an insulative housing 80 including a mating space 81 defined in a center area thereof, a platform 82 projecting into the mating space 81, and a plurality of columns of contacts 83 parallelly retained in the insulative housing 80. Each contact 83 comprises a flat contact plate 84 having a pair of opposite interface 840 and a solder tail 85 having a solder ball attached thereon for surface mounting on the backplane. The insulative housing 80 defines a pair of guiding slits 86 in an inner face of the mating space 81 for receiving corresponding guiding ribs 135 of the mating extender 1. When the mating extender 1 is mated with the pair of headers 8, opposite mating parts of the mating extender 1 are received in the mating spaces 81 of the headers 8 with the platforms 82 of the headers 8 received in the mating ports 16 of the mating extender 1. Referring to FIG. 8A, the contact portion 222 of the differential signal contact 22 resiliently abuts against a corresponding interface 840 of the contact plate 84 of the header 8. Because the differential signal contact 22 is formed by two signal semi-contacts 23, each pair of completely overlapped contact portions 222 of the differential signal contacts 22 has a redundant interface 223 for electrically contacting with the interface 840 of the contact plate 84 of the header 8. It should be noted that the interface 223 of the differential signal contact 22 extends in a first plane perpendicular to a second plane which the differential signal wafer 20 lies in. Referring to FIG. 8B, the pair of contact tails 320 of the single-ended signal contact 32 is deflected outwardly due to the insertion of corresponding contact plate 84 of the header 8. The contact portions 322 of the pair of contact tails 320 resiliently sandwich the corresponding contact plate 84 of the header 8 therebetween. Referring to FIG. 8C, likewise, the pair of contact tails 420 of the grounding contact 42 is deflected outwardly due to the insertion of corresponding contact plate 84 of the header 8. The contact portions 422 of the pair of contact tails 420 resiliently sandwich the corresponding contact plate 84 of the header 8 therebetween. It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a mating extender, and more particularly to a mating extender which is able to vary in height and is adapted for simultaneously and electrically connecting with a pair of headers respectively mounted on two printed circuit boards. 2. Description of Related Art U.S. Pat. No. 6,152,747 discloses an electrical connector assembly comprising a plug and a receptacle. The plug and the receptacle both comprise a number of parallel modules. Each module comprises an insulative support, a plurality of signal contacts attached on one side of the support and a shielding plate attached on another side of the support. Each signal contact comprises a tail having a solder ball attached thereon. The shielding plate is formed with a plurality of end portions each having a solder ball attached thereon. The solder balls on the signal contacts and the shielding plate lie in a common plane. The plug is adapted for being surface mounted onto a first printed circuit board with the solder balls soldered onto corresponding pads on the first printed circuit board. The receptacle is adapted for being surface mounted onto a second printed circuit board positioned parallelly to the first printed circuit board with the solder balls soldered onto corresponding pads on the second printed circuit board. In some applications, a large distance is required to be kept between the first and second printed circuit boards. Therefore, a high profile plug or receptacle is accordingly designed to satisfy this requirement. However, as the height of the plug or the receptacle increases, it becomes more difficult to surface solder the plug or the receptacle to the printed circuit boards. Hence, a mating extender between the plug and the receptacle is desired to overcome the disadvantage of the prior art. | <SOH> SUMMARY OF THE INVENTION <EOH>An object of the present invention is to provide a mating extender for simultaneously and electrically connecting with a pair of headers respectively mounted on two parallel printed circuit boards to match different distances between the printed circuit boards. Another object of the present invention is to provide a mating extender comprising a plurality of contacts each having a redundant interface. To achieve the above object, an mating extender electrically engages with a pair of complementary connectors. The mating extender comprises an insulative housing having first and second mating sections, and a number of wafers parallelly assembled into the insulative housing. Each wafer comprises an insulative frame and a plurality of contacts each formed by a pair of electrically stacked semi-contacts. Each contact has an intermediate portion retained in the insulative frame, a pair of first contact tails and a pair of second contact tails at opposite ends of the intermediate portion and received in the first and the second mating sections of the insulative housing, respectively. Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. | 20050120 | 20060912 | 20060720 | 94233.0 | H01R1200 | 0 | NGUYEN, TRUC T | MATING EXTENDER FOR ELECTRICALLY CONNECTING WITH TWO ELECTRICAL CONNECTORS | UNDISCOUNTED | 0 | ACCEPTED | H01R | 2,005 |
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11,040,303 | ACCEPTED | Method and apparatus for FAIMS for in-line analysis of multiple samples | A method of separating ions includes providing a FAIMS analyzer region including an ion inlet orifice for providing ions thereto, and providing a sample holder along a side of the ion inlet orifice that is opposite the FAIMS analyzer. A sample material is applied to the sample holder such that sample material is disposed about first and second points along the sample holder, a distance between the first and second points being greater than a maximum dimension of the ion inlet orifice. The first point is aligned with the ion inlet orifice, and the sample material disposed about the first point is irradiated with laser light of a predetermined wavelength. Next, the sample holder is moved relative to the ion inlet so as to align the second point with the ion inlet orifice, and the sample material disposed about the second point is irradiated with laser light of a predetermined wavelength. | 1. An apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice defined within a portion of the first electrode, for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source comprising a laser light source and a multiple sample holder, the multiple sample holder disposed within the region that is external to the analyzer region for supporting each of a plurality of discrete sample portions, during different non-overlapping periods of time, in an aligned relationship with the ion inlet orifice, wherein the laser light source is synchronized to irradiate, with light of a predetermined wavelength, each of the plurality of discrete sample portions when in the aligned relationship with the ion inlet orifice. 2. An apparatus according to claim 1, wherein the multiple sample holder comprises a support material for supporting a plurality of discrete target regions, each discrete target region of the plurality for supporting one discrete sample portion. 3. An apparatus according to claim 2, wherein the multiple sample holder comprises one row of discrete target regions. 4. An apparatus according to claim 2, wherein the multiple sample holder comprises a two-dimensional array of discrete target regions. 5. An apparatus according to claim 2, wherein at least some of the discrete target regions comprise a mesh material. 6. An apparatus according to claim 5, wherein the mesh material is an electrically conductive material. 7. An apparatus according to claim 2, wherein at least some of the discrete target regions are at least partly porous for supporting a flow of a gas therethrough. 8. An apparatus according to claim 2, wherein each discrete target portion has a front surface for being disposed in a facing relationship with the ion inlet orifice, and wherein during use the one discrete sample portion is supported on the front surface. 9. An apparatus according to claim 8, wherein each discrete target region is at least partially transmissive to the light of a predetermined wavelength and wherein the laser light source is disposed for irradiating a back surface of each discrete target region. 10. An apparatus according to claim 8, comprising a laser orifice defined within the second electrode, wherein the laser light source is disposed for launching the light of a predetermined wavelength along an optical path including the laser orifice and the ion inlet orifice, for irradiating the front surface of each discrete target region. 11. An apparatus according to claim 10, wherein the optical path is a folded optical path including a reflective surface. 12. An apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice comprising a finite-sized opening that is defined within a portion of the first electrode, the ion inlet orifice for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source for producing ions from a sample material, the laser-based ionization source comprising: a sample holder disposed within the region that is external to the analyzer region, the sample holder having at least a target region for supporting a sample material, the at least a target region including a first portion and a second portion, the first portion and the second portion combined having a total surface area that is larger than the finite-sized opening of the ion inlet orifice; an actuator for moving the sample holder relative to the ion inlet orifice, so as to align the first portion of the at least a target region with the ion inlet orifice during a first period of time and to align the second portion of the at least a target region with the ion inlet orifice during a second period of time; and, a laser light source disposed to irradiate, with light of a predetermined wavelength, the first portion of the at least a target region during the first period of time and the second portion of the at least a target region during the second period of time. 13. An apparatus according to claim 12, wherein the sample holder is a multiple sample holder and wherein the first portion of the at least a target region is a first discrete target region and the second portion of the at least a target region is a second discrete target region. 14. An apparatus according to claim 13, wherein the multiple sample holder comprises one row of discrete target regions including the first discrete target region and the second discrete target region. 15. An apparatus according to claim 13, wherein at least one of the first discrete target region and the second discrete target region is at least partly porous for supporting a flow of a gas therethrough. 16. An apparatus according to claim 12, wherein the sample holder comprises a plurality of discrete target regions, each discrete target region for supporting a sample material and being spaced-apart from every other discrete target region of the plurality of discrete target regions. 17. An apparatus according to claim 16, wherein each discrete target region has a front surface for being disposed in a facing relationship with the ion inlet orifice, and wherein during use the sample material is supported on the front surface. 18. An apparatus according to claim 17, wherein each discrete target region is at least partially transmissive to the light of a predetermined wavelength and wherein the laser light source is disposed for irradiating a back surface of each discrete target region. 19. An apparatus according to claim 17, comprising a laser orifice defined within the second electrode, wherein the laser light source is disposed for launching the light of a predetermined wavelength along an optical path including the laser orifice and the ion inlet orifice, for irradiating the front surface of each discrete target region. 20. An apparatus according to claim 16, wherein at least some of the discrete target regions are at least partly porous for supporting a flow of a gas therethrough. 21. A method of separating ions, comprising: providing a FAIMS analyzer region including an ion inlet orifice for providing ions thereto; providing a sample holder along a side of the ion inlet orifice that is opposite the FAIMS analyzer region; applying a sample material to the sample holder such that sample material is disposed about first and second points along the sample holder, a distance between the first and second points being greater than a maximum dimension of the ion inlet orifice; aligning the first point with the ion inlet orifice; irradiating the sample material disposed about the first point with laser light of a predetermined wavelength; moving the sample holder relative to the ion inlet so as to align the second point with the ion inlet orifice; and, irradiating the sample material disposed about the second point with laser light of a predetermined wavelength. 22. A method according to claim 21, wherein irradiating the sample material comprises irradiating a side of the sample holder on which the sample material is disposed. 23. A method according to claim 21, wherein irradiating the sample material comprises irradiating a side of the sample holder opposite a side on which the sample material is disposed. 24. A method according to claim 21, wherein applying a sample material to the sample holder comprises applying a first portion of an effluent from a condensed phase separation system about the first point and applying a second portion of an effluent from a condensed phase separation system about the second point. 25. A method according to claim 24, wherein the effluent from a condensed phase separation system is applied continuously between the first point and the second point. | This application claims benefit from U.S. Provisional Application No. 60/537,881 filed Jan. 22, 2004. FIELD OF THE INVENTION The instant invention relates generally to High-Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS), and more particularly to FAIMS for in-line analysis of multiple samples. BACKGROUND OF THE INVENTION Biochemical and pharmaceutical applications have requirements for rapid screening and detection of compounds in extremely complex mixtures. Advances in chemical analysis technology applied to these fields must achieve a high degree of specificity in separations and incorporate systems that avoid slow separations, especially those involving chromatography and electrophoresis. At present, the compounds in complex mixtures are separated and analyzed by chromatographic and electrophoretic methods combined with atmospheric pressure ionization-mass spectrometry (API-MS). In these separation techniques, a portion of a sample is introduced as a discrete pulse into the sample inlet of the API-MS system. The sample components are separated either through a component-specific interaction with mobile or stationary phases, or by differences in the drift velocities of components under the influence of electric fields. Because of the time that it takes for the components to migrate, chromatographic and electrophoretic methods require relatively long time periods to accomplish the separation, on the order of several minutes, whereas analysis by mass spectrometric methods provides data almost immediately. In practice, therefore, the mass spectrometer spends significant periods of time waiting for the arrival of transient signals. This is inefficient since the separation technology is very much less expensive than the MS instrumentation. The above-mentioned problem is reduced when the separation technology operates in a continuous mode, for example the mixture is continuously delivered to the inlet of the separator and the selection of the separated components is electronically controlled. In this manner the MS acquires measurements of selected components in the mixture at almost full efficiency. Optionally, the MS is used to continuously study a particular component in a mixture until sufficient information is acquired. As will be obvious to one of ordinary skill in the art, operation of the separation technology in a continuous mode is impossible using existing chromatographic and electrophoretic techniques because the component of interest arrives only as a transient at the end of the separation. This transient mode of operation limits significantly the number and types of experiments that can be conducted during the lifetime of a given transient signal. Furthermore, if the information that is acquired during the transient is insufficient, a new sample must be injected and a delay is encountered during which the components are being separated. Alternatively, complex mixtures may be studied using tandem mass spectrometry (MS/MS). With this technology, the ions are selected by a first mass analyzer operating at low pressure (e.g., 1×10−5 torr) inside the vacuum chamber of a mass spectrometer, and are directed to enter a gas cell which is held at a higher bath gas pressure (e.g., 1×10−3 torr). Upon entering this chamber, the ions collide with the molecules of bath gas and, if the kinetic energy of the ion is sufficient, the ion dissociates into some compound-specific fragments. The fragments pass out of the higher-pressure gas cell and are analyzed using a second mass analyzer, operating at a lower pressure, similar to that of the first mass analyzer. The advantage of tandem mass spectrometry is that the specificity is exceedingly high because of compound-specific fragmentation patterns that are created during the collision-induced dissociation. However, tandem MS requires considerable method development time and the operator must have expertise to operate the instrument. Furthermore, tandem MS cannot effectively quantify many kinds of isomeric ions (e.g., leucine and isoleucine) when both components coexist in the mixture. Accordingly, tandem MS is most suited to applications based on target compound analysis, where the system is used to search for a series of expected compounds and the identity of the expected fragment ions is known. Under these conditions the MS/MS experiment is capable of detecting ions at exceedingly low abundance, even in the presence of interfering compounds, since the MS/MS spectrum is very compound-specific. Tandem MS is less effective when used to study mixtures containing unknown components at trace concentrations. Since the existence of these unknowns cannot be predicted, the mass spectrum of the mixture must have peaks which are discernible above the background noise. In particular, detection of low intensity ions can be a problem when using the electrospray ionization (ESI) technique, since ESI produces background ions that elevate the baseline intensity along the mass-to-charge ratio axis of a mass spectrum. This background of ions makes detection of unknown trace components difficult, if not impossible. Of course, complex mixtures may also be analyzed using mass spectrometers with extremely high resolution, such as FT-ICR systems. However, high resolution mass spectrometers are very expensive. FAIMS is a relatively new separation technique, which solves a number of the problems that are associated with the above-mentioned prior art techniques. FAIMS separates ions on a continuous basis, with the separation occurring under electronic control. Additionally, FAIMS reduces the background chemical noise inherent to atmospheric pressure ionization techniques, thus reducing the detection limits for unknown components in complex mixtures. Finally, FAIMS optionally is operated in tandem with many of the other technologies that are noted above, because the FAIMS device is located between the ion source and the mass spectrometer. A consequence of this physical location is that the FAIMS apparatus can be operated in conjunction with chromatography, electrophoresis, tandem mass spectrometry and high resolution mass spectrometry, etc. Typically, ions are introduced into a FAIMS device after being formed by atmospheric pressure ionization, such as for instance corona discharge ionization, ionization by radioactive Ni, and electrospray ionization as just a few non-limiting examples. In each of these cases, the sample is one of a liquid and a gas, and in every case the analyte ions are suspended in a gas. One notable exception is found in U.S. Pat. No. 6,653,627, issued on Nov. 25, 2003 in the name of Guevremont et al., which discloses a FAIMS apparatus and method using a laser based ionization source. The entire contents of U.S. Pat. No. 6,653,627 are incorporated herein by reference. In that case, a matrix-supported sample is deposited on a target surface that is disposed within the FAIMS analyzer region, and irradiation is performed using a laser that is disposed external to the FAIMS analyzer region. Since ions are formed within the analyzer region, problems associated with low ion transmission efficiency through an ion inlet are eliminated. Unfortunately, in order to introduce new sample it is necessary to disassemble the FAIMS electrode assembly, remove the existing target surfaces, prepare new target surfaces, introduce the new target surfaces, and finally reassemble the FAIMS electrode assembly. Of course, this sample introduction technique does not support rapid screening of samples, and is very time consuming. Placing the target surface of the laser source at a location that is external to the FAIMS analyzer reduces the time and labor that is required for introducing new samples into the FAIMS. In order to achieve high ion transmission efficiency into the FAIMS analyzer region, the target surface should be located as close as possible to the ion inlet orifice of the FAIMS, and should also be disposed parallel to the ion inlet orifice. Unfortunately, when the target surface is disposed for achieving high ion transmission efficiency, very little space remains for arranging the laser light source at a position for irradiating the target surface. It would be advantageous to provide a method and an apparatus for introducing ions, that are formed using a laser source, through an inlet into a FAIMS analyzer region, with high ion transmission efficiency. It would be further advantageous to provide a method and an apparatus for introducing such ions in a manner that supports rapid screening and in-line analysis of samples. SUMMARY OF THE INVENTION It is an object of at least some of the embodiments of the instant invention to provide a method and an apparatus that overcomes at least some of the above-mentioned limitations of the prior art. It is also an object of at least some of the embodiments of the instant invention to provide a method and an apparatus for introducing into the analyzer region of FAIMS, analyte ions from solid samples or from samples containing large biological and polyatomic molecules. It is also an object of at least some of the embodiments of the instant invention to provide a method and an apparatus for introducing analyte ions from sample compounds, in a manner that supports rapid screening of samples. According to a first aspect of the instant invention, provided is an apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice defined within a portion of the first electrode, for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source comprising a laser light source and a multiple sample holder, the multiple sample holder disposed within the region that is external to the analyzer region for supporting each of a plurality of discrete sample portions, during different non-overlapping periods of time, in an aligned relationship with the ion inlet orifice, wherein the laser light source is synchronized to irradiate, with light of a predetermined wavelength, each of the plurality of discrete sample portions when in the aligned relationship with the ion inlet orifice. According to another aspect of the instant invention, provided is an apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice comprising a finite-sized opening that is defined within a portion of the first electrode, the ion inlet orifice for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source for producing ions from a sample material, the laser-based ionization source comprising: a sample holder disposed within the region that is external to the analyzer region, the sample holder having at least a target region for supporting a sample material, the at least a target region including a first portion and a second portion, the first portion and the second portion combined having a total surface area that is larger than the finite-sized opening of the ion inlet orifice; an actuator for moving the sample holder relative to the ion inlet orifice, so as to align the first portion of the at least a target region with the ion inlet orifice during a first period of time and to align the second portion of the at least a target region with the ion inlet orifice during a second period of time; and, a laser light source disposed to irradiate, with light of a predetermined wavelength, the first portion of the at least a target region during the first period of time and the second portion of the at least a target region during the second period of time. According to yet another aspect of the instant invention, provided is a method of separating ions, comprising: providing a FAIMS analyzer region including an ion inlet orifice for providing ions thereto; providing a sample holder along a side of the ion inlet orifice that is opposite the FAIMS analyzer region; applying a sample material to the sample holder such that sample material is disposed about first and second points along the sample holder, a distance between the first and second points being greater than a maximum dimension of the ion inlet orifice; aligning the first point with the ion inlet orifice; irradiating the sample material disposed about the first point with laser light of a predetermined wavelength; moving the sample holder relative to the ion inlet so as to align the second point with the ion inlet orifice; and, irradiating the sample material disposed about the second point with laser light of a predetermined wavelength. The entire contents of U.S. Provisional application 60/537,881 filed Jan. 22, 2004, are hereby incorporated by reference. BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the invention will now be described in conjunction with the following drawings, in which similar reference numerals designate similar items: FIG. 1 is a simplified longitudinal cross sectional view of a system according to an embodiment of the instant invention, including a MALDI ion source with a multiple sample holder, and a FAIMS; FIG. 2 is a simplified longitudinal cross sectional view of a system according to another embodiment of the instant invention, including an atmospheric pressure MALDI ion source with a multiple sample holder, and a FAIMS; FIG. 3a is a partial longitudinal cross sectional view of a m-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 3b is a top view of a m-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 3c is an enlarged top view of one discrete target region of a m-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 4a is a partial longitudinal cross sectional view of a 1-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 4b is a top view of a 1-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 4c is an enlarged top view of one discrete target region of a 1-row by n-column multiple sample holder according to an embodiment of the instant invention; FIG. 5 is a simplified block diagram of an automated sampling system that utilizes a multiple sample holder, in accordance with an embodiment of the instant invention; and, FIG. 6 is a simplified block diagram of another automated sampling system that utilizes a multiple sample holder, in accordance with an embodiment of the instant invention. DESCRIPTION OF EMBODIMENTS OF THE INSTANT INVENTION Exemplary embodiments of the invention will now be described in conjunction with the accompanying drawings. The following description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments disclosed, but is to be accorded the widest scope consistent with the principles and features disclosed herein. Throughout the detailed description, reference is made primarily to atmospheric pressure MALDI, although it is to be understood that other atmospheric pressure ionization techniques, particularly laser based techniques such as atmospheric pressure laser desorption chemical ionization (AP/LD/CI), are readily interfaced to FAIMS using the general concepts presented herein. Furthermore, for the following discussions it is inconvenient to list all the possible versions of atmospheric pressure laser desorption chemical ionization (AP/LD/CI), atmospheric pressure matrix assisted laser desorption/ionization (MALDI), and so on, that appear in the literature. Accordingly, the word MALDI is used as a representative example of one of many laser based ionization schemes that are appropriate for producing ions within the context of the embodiments of the instant invention. The laser optionally desorbs the molecule of interest from a surface, a matrix, or a polymer support as some non-limiting examples, and the laser beam may or may not be involved in the ionization process. Optionally, hybrid schemes that include more than one process are used to produce ions. For example, ions are produced by laser desorption with ionization using a second laser for multi-photon excitation. In another example, molecules of a sample are volatilized from a surface followed by gas-phase chemical ionization using a remotely produced reactant ion. These examples are presented merely to illustrate the nature of ionization methods appropriate for the inventions described below and are not intended to limit the scope of possible laser-based ionization methods that can be used in conjunction with the instant invention. The instant invention addresses the problem of combining a laser beam and sample holder and a mechanism for desolvating and delivering ions into a FAIMS for ion separation. Finally, although reference is made primarily to atmospheric pressure MALDI, it is understood that the pressure and temperature of the MALDI source and of FAIMS is optionally controllable, and that the operating conditions are selected to obtain a sensitivity and separation as required for the chemical analysis. The examples of operating pressures and temperatures in this application are taken for illustrations and should be considered as non-limiting examples. Referring to FIG. 1, shown is a simplified longitudinal cross sectional view of a system according to an embodiment of the instant invention, including an atmospheric pressure MALDI ion source with a multiple sample holder, and a FAIMS. The FAIMS 100 includes a first FAIMS electrode 102 and a second FAIMS electrode 104. The first FAIMS electrode 102 and the second FAIMS electrode 104 are disposed in a spaced-apart facing arrangement and define a FAIMS analyzer region 106 therebetween. Ions enter the FAIMS analyzer region via an ion inlet orifice 108 that is defined within a portion of the second FAIMS electrode 104. A curtain gas region is provided adjacent to the ion inlet orifice 108, to assist in desolvation of ions and to direct neutral molecules away from the ion inlet orifice 108. Ions in FAIMS 100 are separated by application of an asymmetric waveform dispersion voltage (DV) and a direct current compensation voltage (CV) by power supply 110, which is in electrical communication with the first FAIMS electrode 102 via an electrical coupling 112 and with the second FAIMS electrode 104 via an electrical coupling 114. The voltages applied to the first FAIMS electrode 102 and the second FAIMS electrode 104 create electric fields between these electrodes that separate the ions while the ions are transported by a flow of carrier gas 116 along the analyzer region 106. In FIG. 1 the first FAIMS electrode 102 and the second FAIMS electrode 104 are shown as parallel conductive plates, but are optionally micromachined (MEMS) parallel non-curved or curved surfaces, or further optionally, are non-conductive materials that are coated with a conductive layer. During use, a first sample spot 118a is applied to a first discrete target region 120a, a second sample spot 118b is applied to a second discrete target region 120b, etc. In the embodiment that is shown at FIG. 1, preferably each discrete target region 120a, 120b, etc. is fabricated from a material that is opaque, and therefore does not transmit, light at a wavelength of laser light provided from a laser source 122. Optionally, each discrete target region 120a, 120b, etc. is electrically conductive. Collectively, the discrete target regions 120a, 120b, etc. comprise a multiple sample holder 121. In the instant embodiment, the multiple sample holder 121 is a 1-row by n-column multiple sample strip. A laser beam 124 is projected from the laser light source 122, along an optical path through a laser orifice 126 defined within the first FAIMS electrode 102, through a portion of the analyzer region 106 and outwardly through ion inlet orifice 108 and through a curtain gas orifice 128 defined within a curtain gas plate 130. During separate, non-overlapping periods of time, the laser beam 124 impinges upon the sample spots 118a, 118b, etc. and ionizes some of the compounds contained therein. Advantageously, by passing the laser beam 124 through curtain gas orifice 128 of curtain plate 130, the laser beam 124 strikes the sample spots 118a, 118b, etc. at an angle close to perpendicular to the corresponding discrete target region 120a, 120b, etc. An ion cloud 132 produced by the laser beam impinging upon, for instance, sample spot 118b is directed towards the curtain plate 130 of FAIMS 100 by application of voltages to the multiple sample holder 121 by a not illustrated power supply, and to the curtain plate 130 by power supply 143 via electrical coupling 134. A curtain gas flow 136 is provided in the space between the curtain plate 130 and the second FAIMS electrode 104. A portion 138 of the curtain gas flow 136 passes outwards through curtain gas orifice 128, and an analyzer gas portion 144 flows into the analyzer region 106 between the first FAIMS electrode 102 and the second FAIMS electrode 104, via the ion inlet orifice 108. The portion 138 serves to redirect away from the entrance to FAIMS 100 the neutral molecules that are generated by the laser beam 124 striking the sample spot 118b, for example, and prevents these neutral molecules from entering the space between the curtain plate 130 and the second FAIMS electrode 104. At the same time, the ions 132 are directed towards FAIMS 100 by electric fields generated by voltages applied to the multiple sample holder 121, the curtain plate 130 and the second FAIMS electrode 104. The analyzer gas flow 144 also assists in the transfer of ions into the FAIMS analyzer region 106. Preferably, the each discrete target region 120a, 120b, etc. is at least partly porous or permeable to a flow of a curtain gas 136, such that a portion 138 of the carrier gas 136 is transmitted through the discrete target region 120a, 120b, etc., and therefore carries away neutral molecules generated when a laser beam 124 originating at laser source 122 strikes the sample spot 118a, 118b, etc. For instance, each discrete target region 120a, 120b, etc. is fabricated from a fine metallic mesh or a fine metal screen that has the desired properties of transparency to the laser beam, electrical conductivity and porosity for passage of the flow 138 of a portion of a carrier gas 136. Since each discrete target region 120a, 120b, etc. of the multiple sample holder 121 is moved into a parallel relationship adjacent to the curtain plate 130 prior to the sample spot 1118a, 118b supported thereon being irradiated by the laser beam 124, the ions that are produced are directed in a straight-line trajectory from the discrete target region 120a, 120b, etc. towards the curtain plate 130. The ions pass through the curtain gas orifice 128 and are further directed towards ion inlet orifice 108 in the second FAIMS electrode 104 by the electric field between the curtain plate 130 and the second FAIMS electrode 104. Advantageously, the multiple sample holder 121 and the curtain plate 130 are sufficiently close together during use to maximize the likelihood of ions produced from the sample spots 118a, 118b, etc. entering the curtain gas orifice 128 of the curtain plate 130. Optionally, a seal 140 is provided for establishing a gas-tight fit between the curtain plate 130 and a solid support portion 142 of the multiple sample holder 121. The distance between the multiple sample holder 121 and the curtain plate 130 is established by optimization of the intensity of signals detected for the ions of interest. Note also that it is necessary to prevent contamination from the laser orifice 126 from entering the gas flow in FAIMS. This is achieved optionally by providing a window across the laser orifice 126 through which the laser is directed, or by providing a flow of gas outward from the analyzer region 106 and through laser orifice 126 to carry away potential contaminants. Referring now to FIG. 2, shown is a simplified longitudinal cross sectional view of a system according to another embodiment of the instant invention, including an atmospheric pressure MALDI ion source with a multiple sample holder, and a FAIMS. The system shown at FIG. 2 operates with a modified curtain gas approach for preventing neutrals from entering FAIMS 200. The FAIMS 200 includes a first FAIMS electrode 202 and a second FAIMS electrode 204. The first FAIMS electrode 202 and the second FAIMS electrode 204 are disposed in a spaced-apart facing arrangement and define a FAIMS analyzer region 206 therebetween. Ions enter the FAIMS analyzer region 206 via an ion inlet orifice 208 that is defined within a portion of the second FAIMS electrode 204. Ions in FAIMS 200 are separated by application of an asymmetric waveform dispersion voltage (DV) and a direct current compensation voltage (CV) by power supply 210, which is in electrical communication with the first FAIMS electrode 202 via an electrical coupling 212 and with the second FAIMS electrode 204 via an electrical coupling 214. The voltages applied to the first FAIMS electrode 202 and the second FAIMS electrode 204 create electric fields between these electrodes that separate the ions while the ions are transported by a flow of carrier gas 216 along the analyzer region 206 from the ion inlet orifice to a not illustrated ion outlet. In FIG. 2 the first FAIMS electrode 202 and the second FAIMS electrode 204 are shown as parallel conductive plates, but are optionally micromachined (MEMS) parallel non-curved or curved surfaces, or further optionally are non-conductive materials that are coated with a conductive layer. During use, a first sample spot 218a is applied to a front surface of first discrete target region 220a, a second sample spot 218b is applied to a front surface of second discrete target region 220b, etc. In the embodiment that is shown at FIG. 2, each discrete target region 220a, 220b, etc. is fabricated from a material that is at least one of partially transmissive and partly transmissive to light at a wavelength of laser light provided from a laser source 222. Optionally, each discrete target region 220a, 220b, etc. is electrically conductive. Furthermore, the each discrete target region 220a, 220b, etc. is at least partly porous or permeable to a flow of a carrier gas 216, such that a portion 244 of the carrier gas 216 is transmitted through the discrete target region 220a, 220b, etc., and therefore carries away neutral molecules generated when a laser beam 224 originating at laser source 222 strikes the sample spot 218a, 218b, etc. For instance, each discrete target region 220a, 220b, etc. is fabricated from a fine metallic mesh or a fine metal screen that has the desired properties of transparency to the laser beam, electrical conductivity and porosity for passage of the flow 244 of a portion of a carrier gas 216 out through the ion inlet orifice 208. Collectively, the discrete target regions 220a, 220b, etc. comprise a multiple sample holder 221. In the instant embodiment, the multiple sample holder 221 is a 1-row by n-column multiple sample strip. During use, the laser beam 224 is directed to strike a back surface of each discrete target region 220a, 220b, etc., one at a time, while the sample spot 118a, 118b, etc. is supported at the front surface of the respective discrete target region and facing into the analyzer region 206 of FAIMS 200. A portion of the laser light is transmitted through the discrete target region 220a, 220b, etc. to the sample spot 218a, 218b, etc., and ionizes some of the compounds contained therein. Ions 232 that are produced by the laser beam 224 striking the sample spot, for instance sample spot 218b in FIG. 2, are directed into the FAIMS analyzer region 206. Advantageously, the ions 232 pass almost immediately into the FAIMS analyzer region 206 via ion inlet orifice 208 without traversing a separate curtain gas region that is external to the FAIMS analyzer region 206. Once inside the FAIMS analyzer region 206, those ions that do not posses stable trajectories under the influence of the applied CV and DV are lost rapidly to an electrode surface. Accordingly, the probability of an ion of interest recombining with another ion of opposite polarity is reduced. Furthermore, the neutral molecules generated when the laser beam 224 strikes the sample spot, for instance sample spot 118b, are prevented from entering the FAIMS analyzer region 206 by the flow of gas 244 outwards through the discrete target region 220b. Since each discrete target region 220a, 220b, etc. of the multiple sample holder 221 is moved into a parallel relationship adjacent to the ion inlet orifice 208 of the second FAIMS electrode 204 prior to the sample spot 218a, 218b supported thereon being irradiated by the laser beam 224, the ions that are produced are directed in an efficient manner from the discrete target region 220a, 220b, etc. towards ion inlet orifice 208. Advantageously, the multiple sample holder 221 and the second FAIMS electrode 204 are sufficiently close together during use to maximize the percentage of ions produced from the sample spots 218a, 218b, etc. that enter the ion inlet orifice 208. Optionally, a seal 240 is provided for establishing a gas-tight fit between the second FAIMS electrode 204 and a solid support portion 242 of the multiple sample holder 221. The distance between the multiple sample holder 221 and the second FAIMS electrode 204 is established by optimization of the intensity of signals detected for the ions of interest. In FIG. 2, the first FAIMS electrode 202 and the second FAIMS electrode 204 are shown as planar conductive electrodes. Optionally, electrodes according to other FAIMS electrode geometries are used, such as for instance micromachined (MEMS) parallel non-curved or curved surfaces. Further optionally, the electrodes are fabricated from non-conductive materials and are coated with a conductive outer layer. Many types of FAIMS geometry may optionally be used, including domed inner electrodes, side-to-side configurations, parallel plates, and spherical geometry, as some non-limiting examples. Referring now to FIG. 3a, shown is a partial longitudinal cross sectional view of a m-row by n-column multiple sample holder 300 according to an embodiment of the instant invention. FIG. 3a shows an edge-on view of the multiple sample holder 300, which illustrates that a solid support region 302 is optionally thick relative to discrete target regions 304. The dotted lines of discrete target regions 304 denote in FIG. 3a a mesh material. Preferably the discrete target regions 304 are formed of a thin metallic mesh or screen that is at least partly conductive in order to carry electric charges that are generated when a laser beam strikes a not illustrated sample spot supported on one of the discrete target regions 304. By conducting away electric charges, the mesh or screen does not accumulate sufficient electrostatic charge to create electric fields that adversely affect the formation or transport of ions produced by a pulse of laser radiation striking the sample spot. When mounted to a FAIMS system, in a manner similar to that shown in FIG. 1 or FIG. 2, the multiple sample holder 300 is translated to bring each of the discrete target regions 304 into juxtaposition with an ion inlet orifice of the FAIMS system. To this end, preferably an actuator (not shown) is provided for translating the multiple sample holder relative to the ion inlet, in order to make analytical measurements on each one of a plurality of samples, supported one sample on each discrete target region 304, in rapid succession or in-line with another separation technique. Optionally, the discrete target regions 304 are formed of a material that is also partly transparent to the wavelength of the laser radiation, for supporting irradiation of the sample spot by a laser beam that impinges on a back surface of the discrete target region, as shown for example at FIG. 2. Referring now to FIG. 3b, shown is a top view of a m-row by n-column multiple sample holder according to an embodiment of the instant invention. The number of rows and the number of columns of discrete target regions 304 in the multiple sample holder 300 is not critical. Referring now to FIG. 3c, shown is an enlarged top view of one discrete target region of a m-row by n-column multiple sample holder according to an embodiment of the instant invention. The discrete target region 304 is preferably formed of a thin metallic mesh or screen. During use, a spot of a sample is applied to a front surface of the discrete target region 304. Optionally, a spot of a sample is applied to a back surface of the discrete target region 304, and the sample material is carried through the mesh or screen material to the front side by capillary action. Referring now to FIG. 4a, shown is a partial longitudinal cross sectional view of a 1-row by n-column multiple sample holder 400 according to an embodiment of the instant invention. According to this embodiment, the multiple sample holder 400 is formed into an elongated strip. FIG. 4a shows an edge-on view of the multiple sample holder 400, which illustrates that a solid support region 402 is optionally thick relative to discrete target regions 404. The dotted lines of discrete target regions 404 denote in FIG. 4a a mesh material. Preferably the discrete target regions 404 are formed of a thin metallic mesh or screen that is at least partly conductive in order to carry electric charges that are generated when a laser beam strikes a not illustrated sample spot supported on one of the discrete target regions 404. By carrying away electric charges, the mesh or screen does not accumulate sufficient electrostatic charge to create electric fields that adversely affect the formation or transport of ions produced by a pulse of laser radiation striking the sample spot. When mounted to a FAIMS system, in a manner similar to that shown in FIG. 1 or FIG. 2, the multiple sample holder 400 is translated to bring each of the discrete target regions 404 into juxtaposition with an ion inlet orifice of the FAIMS system. To this end, preferably an actuator (not shown) is provided for translating the multiple sample holder 400 relative to the ion inlet, in order to make analytical measurements on each one of a plurality of samples, supported one sample on each discrete target region 404, in rapid succession or in-line with another separation technique. Optionally, the discrete target regions 404 are formed of a material that is also partly transparent to the wavelength of the laser radiation, for supporting irradiation of the sample spot by a laser beam that impinges on a back surface of the discrete target region, as shown for example at FIG. 2. Referring now to FIG. 4b, shown is a top view of a 1-row by n-column multiple sample strip according to an embodiment of the instant invention. The number of columns is not critical. Referring now to FIG. 4c, shown is an enlarged top view of one discrete target region 404 of a 1-row by n-column multiple sample strip according to an embodiment of the instant invention. FIG. 4c shows additional optional features of the discrete target region 404. In particular, the discrete target region 404 is fabricated optionally from a thin material, preferably a metallic foil, which includes a non-perforated sample deposition region 408 that is surrounded by a region of gas transport holes 406. Each sample is sprayed, or otherwise deposited, on one of the sample deposition regions 408. During automatic multiple sample operation, a not illustrated actuator brings each sample deposition region 408 of a discrete target region 404 into the optical path of a laser beam of a not illustrated MALDI laser. The neutral molecules of sample and matrix (if used) are carried in a direction away from FAIMS by the gas flowing outwards through the gas transport holes 406. In this case, the sample is deposited on a side of the sample deposition region 408 that faces towards the ion inlet orifice of FAIMS. Optionally, the discrete target regions 404 are formed of a material that is also partly transparent to the wavelength of the laser radiation, for supporting irradiation of the sample spot by a laser beam that impinges on a back surface of the sample deposition region 408 of the discrete target region, as shown for example at FIG. 2. Referring now to FIG. 5, shown is a simplified block diagram of an automated sampling system that utilizes a multiple sample holder, in accordance with an embodiment of the instant invention. In FIG. 5, the multiple sample holder is provided in the form of a multiple sample holder strip 500, similar to the multiple sample holder shown at FIG. 4b. During use, the multiple sample holder strip 500 is held in a coil or similar reservoir 502. In operation this sample holder strip 500 is transported past the tip of a sample delivery capillary 504 that is part of a sample applicator 506. The control of this sample application, and the reservoirs of individual sample to be applied are housed in the autosampler 508. After application of the sample, the multiple sample holder strip 500 is translated using a not illustrated actuator to a MALDI ion forming region 510 that is adjacent a not illustrated ion inlet orifice of FAIMS 512. Further detail of the ion forming region 510 is shown at FIG. 1. Still referring to FIG. 5, after each sample is analyzed in region 510, the multiple sample holder strip 500 is stepwise translated using the actuator, to bring a next discrete target region of the multiple sample holder strip 500 to the ion forming region 510. One or more pulses of laser beam 514 generated by laser source 516 are directed to the sample, and ions are formed by a MALDI and/or gas phase ionization process. The ions thereby formed are analyzed in FAIMS 512, and are optionally further analyzed by other FAIMS or detection/analyzers, such as for instance mass spectrometry. In the embodiment shown in FIG. 5 the laser beam 514 passes through at least one of the electrodes of FAIMS 512, so that the multiple sample holder strip 500 does not have to be transparent to the laser beam. Optionally, the laser source 516 is relocated in such a way that the laser beam 514 strikes the multiple sample holder strip 500 from a side opposite the deposited sample, as is shown in FIG. 2. Referring now to FIG. 6, shown is a simplified block diagram of another automated sampling system that utilizes a multiple sample holder, in accordance with an embodiment of the instant invention. Elements labeled with the same numerals have the same function as those illustrated in FIG. 5. However, unlike FIG. 5 the sample is not provided by an autosampler which is designed to apply discrete types of samples individually on the multiple sample holder strip 500. Instead, the sample is provided from a condensed phase separation system 600. Injector unit 602 injects a portion of a sample into separation system 604 and the components of the sample are separated within the separation system 604. The effluent from such a separation typically contains the components and/or subsets of the components delivered, sequentially in time, out of the outlet capillary 606 of the separation system 604. The flowing liquid effluent is then directed through a sampler system 608 that has provision for applying portions of the liquid via a capillary applicator 610 to the multiple sample holder strip 500. The multiple sample holder strip 500 optionally includes individual discrete target regions, such as the discrete target regions 404 shown at FIG. 4b. Preferably for this application, the multiple sample holder strip 500 supports application of a continuous and non-interrupted flow of sample to the surface of multiple sample holder strip 500. A not illustrated actuator is used to continuously pass the multiple sample holder strip 500 through the MALDI laser beam 514, for continuous recording of the components eluted from the condensed phase separations system 600. Optionally, computer programming of the actuator supports automatically slowing down the transport of multiple sample holder strip 500 when few (or no) compounds of interest are being eluted from the condensed phase separation system 600, and increasing the transport speed during delivery of mixtures of interest. Further optionally, a portion of a distance that the multiple sample holder strip 500 travels between the capillary applicator 610 and the MALDI ionization region 510, includes a sample dryer for drying or otherwise modifying the samples deposited on the multiple sample holder strip 500. Referring now to FIG. 7, shown is a simplified flow diagram of a method of separating ions according to an embodiment of the instant invention. At step 1000, a sample material is applied to a sample holder, such that sample material is disposed about first and second points along the sample holder. In particular, a distance between the first and second points is greater than a maximum dimension of an ion inlet orifice of a FAIMS analyzer. At step 1002, the first point is aligned with the ion inlet orifice of the FAIMS analyzer. At step 1004 the sample material disposed about the first point is irradiated with laser light of a predetermined wavelength. At step 1006, the sample holder is moved relative to the ion inlet so as to align the second point with the ion inlet orifice of the FAIMS analyzer. At step 1008, the sample material disposed about the second point is irradiated with laser light of a predetermined wavelength. Numerous other embodiments may be envisaged without departing from the spirit and scope of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>Biochemical and pharmaceutical applications have requirements for rapid screening and detection of compounds in extremely complex mixtures. Advances in chemical analysis technology applied to these fields must achieve a high degree of specificity in separations and incorporate systems that avoid slow separations, especially those involving chromatography and electrophoresis. At present, the compounds in complex mixtures are separated and analyzed by chromatographic and electrophoretic methods combined with atmospheric pressure ionization-mass spectrometry (API-MS). In these separation techniques, a portion of a sample is introduced as a discrete pulse into the sample inlet of the API-MS system. The sample components are separated either through a component-specific interaction with mobile or stationary phases, or by differences in the drift velocities of components under the influence of electric fields. Because of the time that it takes for the components to migrate, chromatographic and electrophoretic methods require relatively long time periods to accomplish the separation, on the order of several minutes, whereas analysis by mass spectrometric methods provides data almost immediately. In practice, therefore, the mass spectrometer spends significant periods of time waiting for the arrival of transient signals. This is inefficient since the separation technology is very much less expensive than the MS instrumentation. The above-mentioned problem is reduced when the separation technology operates in a continuous mode, for example the mixture is continuously delivered to the inlet of the separator and the selection of the separated components is electronically controlled. In this manner the MS acquires measurements of selected components in the mixture at almost full efficiency. Optionally, the MS is used to continuously study a particular component in a mixture until sufficient information is acquired. As will be obvious to one of ordinary skill in the art, operation of the separation technology in a continuous mode is impossible using existing chromatographic and electrophoretic techniques because the component of interest arrives only as a transient at the end of the separation. This transient mode of operation limits significantly the number and types of experiments that can be conducted during the lifetime of a given transient signal. Furthermore, if the information that is acquired during the transient is insufficient, a new sample must be injected and a delay is encountered during which the components are being separated. Alternatively, complex mixtures may be studied using tandem mass spectrometry (MS/MS). With this technology, the ions are selected by a first mass analyzer operating at low pressure (e.g., 1×10 −5 torr) inside the vacuum chamber of a mass spectrometer, and are directed to enter a gas cell which is held at a higher bath gas pressure (e.g., 1×10 −3 torr). Upon entering this chamber, the ions collide with the molecules of bath gas and, if the kinetic energy of the ion is sufficient, the ion dissociates into some compound-specific fragments. The fragments pass out of the higher-pressure gas cell and are analyzed using a second mass analyzer, operating at a lower pressure, similar to that of the first mass analyzer. The advantage of tandem mass spectrometry is that the specificity is exceedingly high because of compound-specific fragmentation patterns that are created during the collision-induced dissociation. However, tandem MS requires considerable method development time and the operator must have expertise to operate the instrument. Furthermore, tandem MS cannot effectively quantify many kinds of isomeric ions (e.g., leucine and isoleucine) when both components coexist in the mixture. Accordingly, tandem MS is most suited to applications based on target compound analysis, where the system is used to search for a series of expected compounds and the identity of the expected fragment ions is known. Under these conditions the MS/MS experiment is capable of detecting ions at exceedingly low abundance, even in the presence of interfering compounds, since the MS/MS spectrum is very compound-specific. Tandem MS is less effective when used to study mixtures containing unknown components at trace concentrations. Since the existence of these unknowns cannot be predicted, the mass spectrum of the mixture must have peaks which are discernible above the background noise. In particular, detection of low intensity ions can be a problem when using the electrospray ionization (ESI) technique, since ESI produces background ions that elevate the baseline intensity along the mass-to-charge ratio axis of a mass spectrum. This background of ions makes detection of unknown trace components difficult, if not impossible. Of course, complex mixtures may also be analyzed using mass spectrometers with extremely high resolution, such as FT-ICR systems. However, high resolution mass spectrometers are very expensive. FAIMS is a relatively new separation technique, which solves a number of the problems that are associated with the above-mentioned prior art techniques. FAIMS separates ions on a continuous basis, with the separation occurring under electronic control. Additionally, FAIMS reduces the background chemical noise inherent to atmospheric pressure ionization techniques, thus reducing the detection limits for unknown components in complex mixtures. Finally, FAIMS optionally is operated in tandem with many of the other technologies that are noted above, because the FAIMS device is located between the ion source and the mass spectrometer. A consequence of this physical location is that the FAIMS apparatus can be operated in conjunction with chromatography, electrophoresis, tandem mass spectrometry and high resolution mass spectrometry, etc. Typically, ions are introduced into a FAIMS device after being formed by atmospheric pressure ionization, such as for instance corona discharge ionization, ionization by radioactive Ni, and electrospray ionization as just a few non-limiting examples. In each of these cases, the sample is one of a liquid and a gas, and in every case the analyte ions are suspended in a gas. One notable exception is found in U.S. Pat. No. 6,653,627, issued on Nov. 25, 2003 in the name of Guevremont et al., which discloses a FAIMS apparatus and method using a laser based ionization source. The entire contents of U.S. Pat. No. 6,653,627 are incorporated herein by reference. In that case, a matrix-supported sample is deposited on a target surface that is disposed within the FAIMS analyzer region, and irradiation is performed using a laser that is disposed external to the FAIMS analyzer region. Since ions are formed within the analyzer region, problems associated with low ion transmission efficiency through an ion inlet are eliminated. Unfortunately, in order to introduce new sample it is necessary to disassemble the FAIMS electrode assembly, remove the existing target surfaces, prepare new target surfaces, introduce the new target surfaces, and finally reassemble the FAIMS electrode assembly. Of course, this sample introduction technique does not support rapid screening of samples, and is very time consuming. Placing the target surface of the laser source at a location that is external to the FAIMS analyzer reduces the time and labor that is required for introducing new samples into the FAIMS. In order to achieve high ion transmission efficiency into the FAIMS analyzer region, the target surface should be located as close as possible to the ion inlet orifice of the FAIMS, and should also be disposed parallel to the ion inlet orifice. Unfortunately, when the target surface is disposed for achieving high ion transmission efficiency, very little space remains for arranging the laser light source at a position for irradiating the target surface. It would be advantageous to provide a method and an apparatus for introducing ions, that are formed using a laser source, through an inlet into a FAIMS analyzer region, with high ion transmission efficiency. It would be further advantageous to provide a method and an apparatus for introducing such ions in a manner that supports rapid screening and in-line analysis of samples. | <SOH> SUMMARY OF THE INVENTION <EOH>It is an object of at least some of the embodiments of the instant invention to provide a method and an apparatus that overcomes at least some of the above-mentioned limitations of the prior art. It is also an object of at least some of the embodiments of the instant invention to provide a method and an apparatus for introducing into the analyzer region of FAIMS, analyte ions from solid samples or from samples containing large biological and polyatomic molecules. It is also an object of at least some of the embodiments of the instant invention to provide a method and an apparatus for introducing analyte ions from sample compounds, in a manner that supports rapid screening of samples. According to a first aspect of the instant invention, provided is an apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice defined within a portion of the first electrode, for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source comprising a laser light source and a multiple sample holder, the multiple sample holder disposed within the region that is external to the analyzer region for supporting each of a plurality of discrete sample portions, during different non-overlapping periods of time, in an aligned relationship with the ion inlet orifice, wherein the laser light source is synchronized to irradiate, with light of a predetermined wavelength, each of the plurality of discrete sample portions when in the aligned relationship with the ion inlet orifice. According to another aspect of the instant invention, provided is an apparatus for separating ions, comprising: a FAIMS analyzer comprising a first electrode and a second electrode that is spaced apart from the first electrode, a space between the first electrode and the second electrode defining an analyzer region; an ion inlet orifice comprising a finite-sized opening that is defined within a portion of the first electrode, the ion inlet orifice for providing fluid communication between the analyzer region and a region that is external to the analyzer region; and, a laser-based ionization source for producing ions from a sample material, the laser-based ionization source comprising: a sample holder disposed within the region that is external to the analyzer region, the sample holder having at least a target region for supporting a sample material, the at least a target region including a first portion and a second portion, the first portion and the second portion combined having a total surface area that is larger than the finite-sized opening of the ion inlet orifice; an actuator for moving the sample holder relative to the ion inlet orifice, so as to align the first portion of the at least a target region with the ion inlet orifice during a first period of time and to align the second portion of the at least a target region with the ion inlet orifice during a second period of time; and, a laser light source disposed to irradiate, with light of a predetermined wavelength, the first portion of the at least a target region during the first period of time and the second portion of the at least a target region during the second period of time. According to yet another aspect of the instant invention, provided is a method of separating ions, comprising: providing a FAIMS analyzer region including an ion inlet orifice for providing ions thereto; providing a sample holder along a side of the ion inlet orifice that is opposite the FAIMS analyzer region; applying a sample material to the sample holder such that sample material is disposed about first and second points along the sample holder, a distance between the first and second points being greater than a maximum dimension of the ion inlet orifice; aligning the first point with the ion inlet orifice; irradiating the sample material disposed about the first point with laser light of a predetermined wavelength; moving the sample holder relative to the ion inlet so as to align the second point with the ion inlet orifice; and, irradiating the sample material disposed about the second point with laser light of a predetermined wavelength. The entire contents of U.S. Provisional application 60/537,881 filed Jan. 22, 2004, are hereby incorporated by reference. | 20050121 | 20070515 | 20050728 | 97276.0 | 0 | HASHMI, ZIA R | METHOD AND APPARATUS FOR FAIMS FOR IN-LINE ANALYSIS OF MULTIPLE SAMPLES | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,040,453 | ACCEPTED | Pipe running tool | A pipe running tool for use in an oil drilling system and the like comprises a lower drive shaft adapted to engage a drive shaft of a top drive assembly for rotation therewith. The pipe running tool further includes a lower pipe engagement assembly which is driven to rotate by the lower drive shaft, and is designed to releasably engage a pipe segment in such a manner to substantially prevent relative rotation between the two. Thus, when the lower pipe engagement assembly is actuated to securely hold a pipe segment, the top drive assembly may be actuated to rotate the top drive output shaft, which causes the lower drive shaft and lower pipe engagement assembly to rotate, which in turn rotates the pipe segment. | 1. A pipe running tool mountable on a rig for use in handling pipe segments and for engaging the pipe segments to a string of pipe, the pipe running tool comprising: a top drive assembly adapted to be connected to the rig for vertical displacement of the top drive assembly relative to the rig, the top drive assembly including a drive shaft, the top drive assembly being operative to rotate the drive shaft; and a lower pipe engagement assembly including a central passageway sized for receipt of the pipe segment, the lower pipe engagement assembly including a powered pipe engaging mechanism that is selectively driven into a pipe engagement position to forcibly yet releasably engage the pipe segment and substantially prevent relative rotation therebetween, the lower pipe engagement assembly being in communication with the drive shaft, whereby actuation of the top drive assembly causes the lower pipe engagement assembly to rotate. 2. The pipe running tool of claim 1, further including a hoist mechanism connected to the lower pipe engagement assembly and operative to hoist a pipe segment into the central passageway of the lower pipe engagement assembly. 3. The pipe running tool of claim 2, wherein the hoist mechanism comprises an axle journaled to the lower pipe engagement member, a pair of pulleys rotatably mounted to the axle, and a gear connected to the axle, whereby the gear may be coupled to a drive system for rotating the axle. 4. The pipe running tool of claim 1, wherein the lower pipe engagement assembly comprises a spider\elevator. 5. The pipe running tool of claim 1, wherein the lower pipe engagement assembly is powered by one of a hydraulic system and a pneumatic system. 6. The pipe running tool of claim 5, wherein the lower pipe engagement assembly comprises a generally cylindrical housing defining a central passageway, and a plurality of slips disposed within the bowl and displaceable radially inwardly to engage a casing segment extending through the opening. 7. The pipe running tool of claim 1, further including a block connected to the top drive assembly and adapted for engaging a plurality of cables connected to the rig. 8. The pipe running tool of claim 7, wherein the drive members comprise hydraulic lift cylinders. 9. A pipe running tool mountable on a rig and designed for use in handling pipe segments and for engaging pipe segments to a pipe string, the pipe running tool comprising: a top drive assembly adapted to be connected to the rig, the top drive assembly including a top drive output shaft, the top drive assembly being operative to rotate the drive shaft; a lower drive shaft coupled to the top drive output shaft and comprising an adjustable segment that is selectively adjustable to adjust the length of the second drive shaft; a lower pipe engagement assembly including a central passageway sized for receipt of the pipe segment, the lower pipe engagement assembly being operative to releasably grasp the pipe segment, the lower pipe engagement assembly being connected to the second drive shaft, whereby actuation of the top drive assembly causes the lower pipe engagement assembly to rotate; and means for applying a force to the second shaft to cause the length of the adjustable segment to be shortened. 10. The pipe running tool of claim 9, wherein the means for applying comprises a load compensator in the form of a pair of hydraulic cylinders. 11. The pipe running tool of claim 9, wherein the lower pipe engagement assembly is actuated by one of a hydraulic system and a pneumatic system. 12. The pipe running tool of claim 9, wherein the lower pipe engagement assembly comprises a generally cylindrical housing defining a central passage and a plurality of slips disposed within the housing and displaceable radially inwardly to engage a casing segment extending through the passage. 13. The pipe running tool of claim 9, further including a block connected to the top drive assembly and adapted for engaging a plurality of cables connected to the rig to selectively raise and lower the top drive assembly. 14. A pipe running tool mountable on a rig and designed for use in connection with a top drive assembly adapted to be connected to the rig for vertical displacement of the top drive assembly relative to the rig, the top drive assembly including a drive shaft, the top drive assembly being operative to rotate the drive shaft, the pipe running tool comprising: a lower pipe engagement assembly comprising: a housing defining a central passageway sized for receipt of a pipe segment, the housing being coupled to the top drive assembly for rotation therewith; a plurality of slips disposed within the housing and displaceable between disengaged and engaged positions; and a powered system connected to the respective slips and operative to selectively drive the slips between the disengaged and engaged positions. 15. The pipe running tool of claim 14, further including a hoist mechanism connected to the lower pipe engagement assembly and operative to hoist a pipe segment into the central passageway of the lower pipe engagement assembly. 16. The pipe running tool of claim 15, wherein the hoist mechanism comprises an axle journaled to the lower pipe engagement member, a pair of pulleys rotatably mounted to the axle, and a gear connected to the axle, whereby the gear may be coupled to a drive system for rotating the axle. 17. The pipe running tool of claim 14, wherein the powered system comprises one of a hydraulic and pneumatic system. 18. The pipe running tool of claim 14, further including a block connected to the top drive assembly and adapted for engaging a plurality of cables connected to the rig. 19. In a system for assembling a pipe string comprising a top drive assembly, a lower pipe engagement assembly coupled to the top drive assembly for rotation therewith and operative to releasably engage a pipe segment, and a load compensator operative to raise the lower pipe engagement assembly relative to the top drive assembly, a method for threadedly engaging a pipe segment with a pipe string, comprising the steps of: actuating the lower pipe engagement assembly to releasably engage a pipe segment; lowering the top drive assembly to bring the pipe segment into contact with the pipe string; monitoring the load on the pipe string; actuating the load compensator to raise the pipe segment a selected distance relative to the pipe string, if the load on the pipe string exceeds a predetermined threshold value; and actuating the top drive assembly to rotate the pipe segment to threadedly engage the pipe segment and pipe string. | CROSS-REFERENCE TO RELATED APPLICATION(S) This application is based on provisional patent application Ser. No. 60/122,915 filed Mar. 5, 1999. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to well drilling operations and, more particularly, to a device for assisting in the assembly of pipe strings, such as casing strings, drill strings and the like. 2. Description of the Related Art The drilling of oil wells involves assembling drill strings and casing strings, each of which comprises a plurality of elongated, heavy pipe segments extending downwardly from an oil drilling rig into a hole. The drill string consists of a number of sections of pipe which are threadedly engaged together, with the lowest segment (i.e., the one extending the furthest into the hole) carrying a drill bit at its lower end. Typically, the casing string is provided around the drill string to line the well bore after drilling the hole and ensure the integrity of the hole. The casing string also consists of a plurality of pipe segments which are threadedly coupled together and formed with through passages sized to receive the drill string and/or other pipe strings. The conventional manner in which plural casing segments are coupled together to form a casing string is a labor-intensive method involving the use of a “stabber” and casing tongs. The stabber is manually controlled to insert a segment of casing into the upper end of the existing casing string, and the tongs are designed to engage and rotate the segment to threadedly connect it to the casing string. While such a method is effective, it is cumbersome and relatively inefficient because the procedure is done manually. In addition, the casing tongs require a casing crew to properly engage the segment of casing and to couple the segment to the casing string. Thus, such a method is relatively labor-intensive and therefore costly. Furthermore, using casing tongs requires the setting up of scaffolding or other like structures, and is therefore inefficient. Others have proposed a casing running tool for assembling casing strings which utilizes a conventional top drive assembly. The tool includes a pivotable manipulator which is designed to engage a pipe segment and raise the pipe segment up into a power assist spider, which relies on gravity to hold the pipe segment. The spider is coupled to the top drive and may be rotated by it. Thus, the pipe segment may be brought into contact with a casing string and the top drive activated to rotate the casing segment and threadedly engage it with the casing string. While such a system provides benefits over the more conventional systems used to assemble casing strings, such a system suffers from shortcomings. One such shortcoming is that the casing segment may not be sufficiently engaged by the power assist spider to properly connect the casing segment with the casing string. In addition, the system fails to provide any means for effectively controlling the load applied to the threads at the bottom of the casing segment. Without the ability to control the load on the threads, cross-threading may occur, resulting in stripped threads and a useless casing segment. Accordingly, it will be apparent to those skilled in the art that there continues to be a need for a device for use in a drilling system which utilizes an existing top drive assembly to efficiently assemble casing and/or drill strings, and which positively engages a pipe segment to ensure proper coupling of the pipe segment to a pipe string. The present invention addresses these needs and others. SUMMARY OF THE INVENTION Briefly, and in general terms, the present invention is directed to a pipe running tool for use in drilling systems and the like to assemble casing and/or drill strings. The pipe running tool is coupled to an existing top drive assembly which is used to rotate a drill string, and includes a powered elevator that is powered into an engaged position to securely engage a pipe segment, for example, a casing segment. Because the elevator is powered into the engaged position, the pipe segment may be properly coupled to an existing pipe string using the top drive assembly. The system of the present invention in one illustrative embodiment is directed to a pipe running tool mountable on a rig and including: a top drive assembly adapted to be connected to the rig for vertical displacement of the top drive assembly relative to the rig, the top drive assembly including a drive shaft, the top drive assembly being operative to rotate the drive shaft; and a lower pipe engagement assembly including a central passageway sized for receipt of the pipe segment, the lower pipe engagement assembly including a powered engagement device that is powered to an engaged position to securely and releasably grasp the pipe segment, the lower pipe engagement assembly being in communication with the drive shaft, whereby actuation of the top drive assembly causes the lower pipe engagement assembly to rotate. In another illustrative embodiment, the present invention is directed to a method of assembling a pipe string, including the steps of: actuating a lower pipe engagement assembly to releasably engage a pipe segment; lowering a top drive assembly to bring the pipe segment into contact with a pipe string; monitoring the load on the pipe string; actuating a load compensator to raise the pipe segment a selected distance relative to the pipe string, if the load on the pipe string exceeds a predetermined threshold value; and actuating the top drive assembly to rotate the pipe segment to threadedly engage the pipe segment and pipe string. Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features of the present invention. DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevated side view of a drilling rig incorporating a pipe running tool according to one illustrative embodiment of the present invention; FIG. 2 is a side view, in enlarged scale, of the pipe running tool of FIG. 1; FIG. 3 is a cross-sectional view taken along the line 3-3 of FIG. 2; FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG. 2; FIG. 5A is a cross-sectional view taken along the line 5-5 of FIG. 4 and showing a spider\elevator in a disengaged position; FIG. 5B is a cross-sectional view similar to FIG. 5A and showing the spider\elevator in an engaged position; FIG. 6 is a block diagram of components included in one illustrative embodiment of the invention; and FIG. 7 is a side view of another illustrative embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following detailed description, like reference numerals will be used to refer to like or corresponding elements in the different figures of the drawings. Referring now to FIGS. 1 and 2, there is shown a pipe running tool 10 depicting one illustrative embodiment of the present invention, which is designed for use in assembling pipe strings, such as drill strings, casing strings, and the like. The pipe running tool 10 comprises, generally, a frame assembly 12, a rotatable shaft 14, and a lower pipe engagement assembly 16 that is coupled to the rotatable shaft for rotation therewith. The pipe engagement assembly is designed for selective engagement of a pipe segment 11 (FIGS. 1, 2, and 5A) to substantially prevent relative rotation between the pipe segment and the pipe engagement assembly. The rotatable shaft 14 is designed for coupling with a top drive output shaft from an existing top drive, such that the top drive, which is normally used to rotate a drill string to drill a well hole, may be used to assemble a pipe string, for example, a casing string or a drill string, as is described in greater detail below. The pipe running tool 10 is designed for use, for example, in a well drilling rig 18. A suitable example of such a rig is disclosed in U.S. Pat. No. 4,765,401 to Boyadjieff, which is expressly incorporated herein by reference as if fully set forth herein. As shown in FIG. 1, the rig includes a frame 20 and a pair of guide rails 22 along which a top drive assembly, generally designated 24, may ride for vertical movement relative to the rig. The top drive assembly is preferably a conventional top drive used to rotate a drill string to drill a well hole, as is described in U.S. Pat. No. 4,605,077 to Boyadjieff, which is expressly incorporated herein by reference. The top drive assembly includes a drive motor 26 and a top drive output shaft 28 extending downwardly from the drive motor, with the drive motor being operative to rotate the drive shaft, as is conventional in the art. The rig defines a drill floor 30 having a central opening 32 through which a drill string and/or casing string 34 is extended downwardly into a well hole. The rig 18 also includes a flush-mounted spider 36 that is configured to releasably engage the drill string and/or casing string 34 and support the weight thereof as it extends downwardly from the spider into the well hole. As is well known in the art, the spider includes a generally cylindrical housing which defines a central passageway through which the pipe string may pass. The spider includes a plurality of slips which are located within the housing and are selectively displaceable between disengaged and engaged positions, with the slips being driven radially inwardly to the respective engaged positions to tightly engage the pipe segment and thereby prevent relative movement or rotation of the pipe segment and the spider housing. The slips are preferably driven between the disengaged and engaged positions by means of a hydraulic or pneumatic system, but may be driven by any other suitable means. Referring primarily to FIG. 2, the pipe running tool 10 includes the frame assembly 12, which comprises a pair of links 40 extending downwardly from a link adapter 42. The link adapter defines a central opening 44 through which the top drive output shaft 28 may pass. Mounted to the link adapter on diametrically opposed sides of the central opening are respective upwardly extending, tubular members 46 (FIG. 1), which are spaced a predetermined distance apart to allow the top drive output shaft 28 to pass therebetween. The respective tubular members connect at their upper ends to a rotating head 48, which is connected to the top drive assembly 24 for movement therewith. The rotating head defines a central opening (not shown) through which the top drive output shaft may pass, and also includes a bearing (not shown) which engages the upper ends of the tubular members and permits the tubular members to rotate relative to the rotating head body, as is described in greater detail below. The top drive output shaft 28 terminates at its lower end in an internally splined coupler 52 which is engaged to an upper end of the lower drive shaft 14 (not shown) which is formed to complement the splined coupler for rotation therewith. Thus, when the top drive output shaft 28 is rotated by the top drive motor 26, the lower drive shaft 14 is also rotated. It will be understood that any suitable interface may be used to securely engage the top and lower drive shafts together. In one illustrative embodiment, the lower drive shaft 14 is connected to a conventional pipe handler, generally designated 56, which may be engaged by a suitable torque wrench (not shown) to rotate the lower drive shaft and thereby make and break connections that require very high torque, as is well known in the art. The lower drive shaft 14 is also formed with a splined segment 58, which is slidably received in an elongated, splined bushing 60 which serves as an extension of the lower drive shaft. The drive shaft and bushing are splined to provide for vertical movement of the shaft relative to the bushing, as is described in greater detail below. It will be understood that the splined interface causes the bushing to rotate when the lower drive shaft rotates. The pipe running tool 10 further includes the lower pipe engagement assembly 16, which in one embodiment comprises a torque transfer sleeve 62 which is securely connected to the lower end of the bushing 60 for rotation therewith. The torque transfer sleeve is generally annular and includes a pair of upwardly projecting arms 64 on diametrically opposed sides of the sleeve. The arms are formed with respective horizontal through passageways (not shown) into which are mounted respective bearings (not shown) which serve to journal a rotatable axle 70 therein, as described in greater detail below. The transfer sleeve connects at its lower end to a downwardly extending torque frame 72 in the form of a pair of tubular members 73, which in turn is coupled to a spider\elevator 74 which rotates with the torque frame. It will be apparent that the torque frame may take many, such as a plurality of tubular members, a solid body, or any other suitable structure. The spider\elevator 74 is preferably powered by a hydraulic or pneumatic system, or alternatively by an electric drive motor or any other suitable powered system. In the embodiment disclosed, the spider\elevator includes a housing 75 which defines a central passageway 76 through which the pipe segment 11 may pass. The spider\elevator also includes a pair of hydraulic or pneumatic cylinders 77 with displaceable piston rods 78 (FIGS. 5A and 5B) which are connected through suitable pivotable linkages 79 to respective slips 80. The linkages are pivotally connected to both the top ends of the piston rods and to the top ends of the slips. The slips include generally planar front gripping surfaces 82, and specially contoured rear surfaces 84 which are designed with such a contour to cause the slips to travel between respective radially outwardly disposed, disengaged positions, and radially inwardly disposed, engaged positions. The rear surfaces of the slips travel along respective downwardly and radially inwardly projecting guiding members 86 which are complementarily contoured and securely connected to the spider body. The guiding members cooperate with the cylinders and linkages to cam the slips radially inwardly and force the slips into the respective engaged positions. Thus, the cylinders (or other actuating means) may be empowered to drive the piston rods downwardly, causing the corresponding linkages to be driven downwardly and therefore force the slips downwardly. The surfaces of the guiding members are angled to force the slips radially inwardly as they are driven downwardly to sandwich the pipe segment 11 between them, with the guiding members maintaining the slips in tight engagement with the pipe segment. To release the pipe segment 11, the cylinders 76 are operated in reverse to drive the piston rods upwardly, which draws the linkages upwardly and retracts the respective slips back to their disengaged positions to release the pipe segment. The guiding members are preferably formed with respective notches 81 which receive respective projecting portions 83 of the slips to lock the slips in the disengaged position (FIG. 5A). The spider\elevator 74 further includes a pair of diametrically opposed, outwardly projecting ears 88 formed with downwardly facing recesses 90 sized to receive correspondingly formed, cylindrical members 92 at the bottom ends of the respective links 40, and thereby securely connect the lower ends of the links to the spider\elevator. The ears may be connected to an annular sleeve 93 which is received over the housing 75, or may be formed integral with the housing. In one illustrative embodiment, the pipe running tool 10 includes a load compensator, generally designated 94. The load compensator preferably is in the form of a pair of hydraulic, double rodded cylinders 96, each of which includes a pair of piston rods 98 that are selectively extendable from, and retractable into, the cylinder. The upper rods connect to a compensator clamp 100, which in turn is connected to the lower drive shaft 14, while the lower rods extend downwardly and connect at the respective lower ends to a pair of ears 102 which are securely mounted to the bushing 60. The hydraulic cylinders may be actuated to draw the bushing upwardly relative to the lower drive shaft 14 by applying a pressure to the cylinders which causes the upper piston rods to retract into the respective cylinder bodies, with the splined interface between the bushing and lower drive shaft allowing the bushing to be displaced vertically relative to the shaft. In that manner, the pipe segment 11 carried by the spider\elevator 74 may be raised vertically to relieve a portion or all of the load applied to the pipe segment 11, as is described in greater detail below. As is shown in FIG. 2, the lower rods are at least partially retracted, resulting in the majority of the load from the pipe running tool 10 is assumed by the top drive output shaft 28. In addition, when a load above a preselected maximum is applied to the pipe segment 11, the cylinders 96 will automatically react the load to prevent the entire load from being applied to the threads of the pipe segment. The pipe running tool 10 still further includes a hoist mechanism, generally designated 104, for hoisting a pipe segment upwardly into the spider\elevator 74. The hoist mechanism is disposed off-axis and includes a pair of pulleys 106 carried by the axle 70, the axle being journaled into the bearings in respective through passageways formed in the arms 64. The hoist mechanism also includes a gear drive, generally designated 108, that may be selectively driven by a hydraulic motor 111 or other suitable drive system to rotate the axle and thus the pulleys. The hoist may also include a brake 115 to prevent rotation of the axle and therefore of the pulleys and lock them in place, as well as a torque hub 116. Therefore, a pair of chains, cables, or other suitable, flexible means may be run over the respective pulleys, extended through a chain well 113, and engaged to the pipe segment 11, and the axle is then rotated by a suitable drive system to hoist the pipe segment vertically and up into position with the upper end of the pipe segment 11 extending into the spider\elevator 74. The pipe running tool 10 preferably further includes an annular collar 109 which is received over the links 40 and which maintains the links locked to the ears 88 and prevents the links from twisting and/or winding. In use, a work crew may manipulate the pipe running tool 10 until the upper end of the tool is aligned with the lower end of the top drive output shaft 28. The pipe running tool 10 is then raised vertically until the splined coupler 52 at the lower end of the top drive output shaft is engaged to the upper end of the lower drive shaft 14 and the links 40 are engaged with the ears 93. The work crew may then run a pair of chains or cables over the respective pulleys 106 of the hoist mechanism 104, connect the chains or cables to a pipe segment 1 1, engage a suitable drive system to the gear 108, and actuate the drive system to rotate the pulleys and thereby hoist the pipe segment upwardly until the upper end of the pipe segment extends through the lower end of the spider\elevator 74. The spider\elevator is then actuated, with the hydraulic cylinders 77 and guiding members 86 cooperating to forcibly drive the respective slips 84 into the engaged positions (FIG. 5B) to positively engage the pipe segment. The slips are preferably advanced to a sufficient extent to prevent relative rotation between the pipe segment and the spider\elevator, such that rotation of the spider\elevator translates into rotation of the pipe segment. The top drive assembly 24 is then lowered relative to the frame 20 by means of the top hoist 25 to drive the threaded lower end of the pipe segment 11 into contact with the threaded upper end of the pipe string 34 (FIG. 1). As shown in FIG. 1, the pipe string is securely held in place by means of the flush-mounted spider 36 or any other suitable structure for securing the string in place, as is well known to those skilled in the art. Once the threads are properly mated, the top drive motor 26 is then actuated to rotate the top drive output shaft, which in turn rotates the lower drive shaft of the pipe running tool 10 and the spider\elevator 74, which causes the coupled pipe segment to rotate and thereby be threadedly engaged to the pipe string. In one embodiment, the pipe segment 11 is intentionally lowered until the lower end of the pipe segment rests on the top of the pipe string 34. The load compensator 94 is then actuated to drive the bushing 60 upwardly relative to the lower drive shaft 14 via the splined interface between the two. The upward movement of the bushing causes the spider\elevator 74 and therefore the coupled pipe segment 11 to be raised, thereby reducing the weight on the threads of the pipe segment. In this manner, the load on the threads can be controlled by actuating the load compensator. Once the pipe segment 11 is threadedly coupled to the pipe string, the top drive assembly 24 is raised vertically to lift the entire pipe string 34, which causes the flush-mounted spider 36 to disengage the string. The top drive assembly 24 is then lowered to advance the string downwardly into the well hole until the upper end of the top pipe segment 11 is close to the drill floor 30, with the entire load of the pipe string being carried by the links 40 while the torque was supplied through shafts. The flush-mounted spider 36 is then actuated to engage the pipe string and suspend it therefrom. The spider\elevator 74 is then controlled in reverse to retract the slips 84 back to the respective disengaged positions (FIG. 5A) to release the pipe string. The top drive assembly 24 is then raised to lift the pipe running tool 10 up to a starting position (such as that shown in FIG. 1) and the process may be repeated with an additional pipe segment 11. Referring to FIG. 6, there is shown a block diagram of components included in one illustrative embodiment of the pipe running tool 10. In this embodiment, the tool includes a conventional load cell 110 or other suitable load-measuring device mounted on the pipe running tool 10 in such a manner that it is in communication with the lower drive shaft 14 to determine the load applied to the lower end of the pipe segment 11. The load cell is operative to generate a signal representing the load sensed, which in one illustrative embodiment is transmitted to a processor 112. The processor is programmed with a predetermined threshold load value, and compares the signal from the load cell with that value. If the load exceeds the value, the processor then controls the load compensator 94 to draw upwardly a selected amount to relieve at least a portion of the load on the threads of the pipe segment. Once the load is at or below the threshold value, the processor controls the top drive assembly 24 to rotate the pipe segment 11 and thereby threadedly engage the pipe segment to the pipe string 34. While the top drive assembly is actuated, the processor continues to monitor the signals from the load cell to ensure that the load on the pipe segment does not exceed the threshold value. Alternatively, the load on the pipe segment 11 may be controlled manually, with the load cell 110 indicating the load on the pipe segment via a suitable gauge or other display, with a work person controlling the load compensator 94 and top drive assembly 24 accordingly. Referring to FIG. 7, there is shown another preferred embodiment of the pipe running tool 200 of the present invention. The pipe running tool includes a hoisting mechanism 202 which is substantially the same as the hoisting mechanism 104 described above. A lower drive shaft 204 is provided and connects at its lower end to a conventional mud-filling device 206 which, as is known in the art, is used to fill a pipe segment, for example, a casing segment, with mud during the assembly process. In one illustrative embodiment, the mud-filling device is a device manufactured by Davies-Lynch Inc. of Texas. The hoisting mechanism 202 supports a pair of chains 208 which engage a slip-type single joint elevator 210 at the lower end of the pipe running tool 200. As is known in the art, the single joint elevator is operative to releasably engage a pipe segment 11, with the hoisting mechanism 202 being operative to raise the single joint elevator and pipe segment upwardly and into the spider\elevator 74. The tool 200 includes the links 40 which define the cylindrical lower ends 92 which are received in generally J-shaped cut-outs 212 formed in diametrically opposite sides of the spider\elevator 74. From the foregoing, it will be apparent that the pipe running tool 10 efficiently utilizes an existing top drive assembly to assemble a pipe string, for example, a casing or drill string, and does not rely on cumbersome casing tongs and other conventional devices. The pipe running tool incorporates the spider\elevator 74, which not only carries pipe segments, but also imparts rotation to them to threadedly engage the pipe segments to an existing pipe string. Thus, the pipe running tool provides a device which grips and torques the pipe segment 11, and which also is capable of supporting the entire load of the pipe string as it is lowered down into the well hole. While several forms of the present invention have been illustrated and described, it will be apparent to those of ordinary skill in the art that various modifications and improvements can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention This invention relates to well drilling operations and, more particularly, to a device for assisting in the assembly of pipe strings, such as casing strings, drill strings and the like. 2. Description of the Related Art The drilling of oil wells involves assembling drill strings and casing strings, each of which comprises a plurality of elongated, heavy pipe segments extending downwardly from an oil drilling rig into a hole. The drill string consists of a number of sections of pipe which are threadedly engaged together, with the lowest segment (i.e., the one extending the furthest into the hole) carrying a drill bit at its lower end. Typically, the casing string is provided around the drill string to line the well bore after drilling the hole and ensure the integrity of the hole. The casing string also consists of a plurality of pipe segments which are threadedly coupled together and formed with through passages sized to receive the drill string and/or other pipe strings. The conventional manner in which plural casing segments are coupled together to form a casing string is a labor-intensive method involving the use of a “stabber” and casing tongs. The stabber is manually controlled to insert a segment of casing into the upper end of the existing casing string, and the tongs are designed to engage and rotate the segment to threadedly connect it to the casing string. While such a method is effective, it is cumbersome and relatively inefficient because the procedure is done manually. In addition, the casing tongs require a casing crew to properly engage the segment of casing and to couple the segment to the casing string. Thus, such a method is relatively labor-intensive and therefore costly. Furthermore, using casing tongs requires the setting up of scaffolding or other like structures, and is therefore inefficient. Others have proposed a casing running tool for assembling casing strings which utilizes a conventional top drive assembly. The tool includes a pivotable manipulator which is designed to engage a pipe segment and raise the pipe segment up into a power assist spider, which relies on gravity to hold the pipe segment. The spider is coupled to the top drive and may be rotated by it. Thus, the pipe segment may be brought into contact with a casing string and the top drive activated to rotate the casing segment and threadedly engage it with the casing string. While such a system provides benefits over the more conventional systems used to assemble casing strings, such a system suffers from shortcomings. One such shortcoming is that the casing segment may not be sufficiently engaged by the power assist spider to properly connect the casing segment with the casing string. In addition, the system fails to provide any means for effectively controlling the load applied to the threads at the bottom of the casing segment. Without the ability to control the load on the threads, cross-threading may occur, resulting in stripped threads and a useless casing segment. Accordingly, it will be apparent to those skilled in the art that there continues to be a need for a device for use in a drilling system which utilizes an existing top drive assembly to efficiently assemble casing and/or drill strings, and which positively engages a pipe segment to ensure proper coupling of the pipe segment to a pipe string. The present invention addresses these needs and others. | <SOH> SUMMARY OF THE INVENTION <EOH>Briefly, and in general terms, the present invention is directed to a pipe running tool for use in drilling systems and the like to assemble casing and/or drill strings. The pipe running tool is coupled to an existing top drive assembly which is used to rotate a drill string, and includes a powered elevator that is powered into an engaged position to securely engage a pipe segment, for example, a casing segment. Because the elevator is powered into the engaged position, the pipe segment may be properly coupled to an existing pipe string using the top drive assembly. The system of the present invention in one illustrative embodiment is directed to a pipe running tool mountable on a rig and including: a top drive assembly adapted to be connected to the rig for vertical displacement of the top drive assembly relative to the rig, the top drive assembly including a drive shaft, the top drive assembly being operative to rotate the drive shaft; and a lower pipe engagement assembly including a central passageway sized for receipt of the pipe segment, the lower pipe engagement assembly including a powered engagement device that is powered to an engaged position to securely and releasably grasp the pipe segment, the lower pipe engagement assembly being in communication with the drive shaft, whereby actuation of the top drive assembly causes the lower pipe engagement assembly to rotate. In another illustrative embodiment, the present invention is directed to a method of assembling a pipe string, including the steps of: actuating a lower pipe engagement assembly to releasably engage a pipe segment; lowering a top drive assembly to bring the pipe segment into contact with a pipe string; monitoring the load on the pipe string; actuating a load compensator to raise the pipe segment a selected distance relative to the pipe string, if the load on the pipe string exceeds a predetermined threshold value; and actuating the top drive assembly to rotate the pipe segment to threadedly engage the pipe segment and pipe string. Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features of the present invention. | 20050120 | 20060829 | 20060112 | 66434.0 | E21B1908 | 1 | NEUDER, WILLIAM P | PIPE RUNNING TOOL | UNDISCOUNTED | 0 | ACCEPTED | E21B | 2,005 |
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11,040,577 | ACCEPTED | Apparatus and method for independent control of on-die termination for ouput buffers of a memory device | An apparatus and method providing independent control of on-die termination (ODT) of output buffers. The ODTs for the buffer circuits of an input/output (I/O) buffer can be enabled and disabled in response to an ODT control signal. Additionally, the ODTs for a first set of the buffer circuits can be enabled and disabled responsive to the ODT control signal and the ODT for at least one of a second set of the buffer circuits is disabled. | 1. An output buffer, comprising: a plurality of buffer circuits, each buffer circuit having an input circuit and an output circuit, and further having an on-die termination (ODT) circuit coupled to the input and output circuits, the ODT circuit having an activation node to which an ODT activation signal is coupled to enable and disable the ODT circuit; and an ODT control circuit coupled to the plurality of buffer circuits and having an ODT mode select node to which an ODT mode select signal is applied and an ODT control node to which an ODT control signal is applied, in response to a first state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for the plurality of buffer circuits, and in response to a second state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for a first set of the plurality of buffer circuits and an inactive ODT signal for a second set of the plurality of buffers circuit. 2. The output buffer of claim 1 wherein the ODT control circuit comprises: a first logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the first set of the plurality of buffer circuits, the first logic circuit configured to generate an active ODT activation signal for the first set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal; and a second logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the second set of the plurality of buffer circuits, the second logic circuit configured to generate an inactive ODT activation signal for the second set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal. 3. The output buffer of claim 1 wherein the second set of the plurality of buffer circuits comprises at least one buffer circuit having a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the output circuit in response to the test control signal. 4. The output buffer of claim 3, further comprising test logic circuit having an input node at which the ODT mode signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the ODT mode select signal. 5. The output buffer of claim 1 wherein the first set of the plurality of buffer circuits comprises a set of buffer circuits coupled to receive data strobe signals and the second set of the plurality of buffer circuits comprises a set of buffer circuits coupled to receive data signals. 6. The output buffer of claim 1, further comprising a buffer control circuit coupled to the plurality of buffer circuits, the buffer control circuit having a first logic circuit configured to enable the output circuits of the first set of the plurality of buffer circuits responsive to an output enable (OE) control signal and further having a second logic circuit configured to enable the output circuits of the second set of the plurality of buffer circuits responsive to the OE control signal. 7. The output buffer of claim 1 wherein the ODT circuit comprises: a pair of series coupled impedance devices; a first switch coupled to a first of the pair of series coupled impedance devices and a voltage supply and having a control node coupled to the activation node; and a second switch coupled to a second of the pair of series coupled impedance devices and ground and having a control node coupled to the activation node, the first and second switches selectively coupling the pair of series coupled impedance devices between the voltage supply and ground responsive the ODT activation signal. 8. An output buffer, comprising: at least one data strobe buffer circuit having an data strobe node at which a read strobe signal is provided and a write strobe signal is received; a plurality of data buffer circuits, each having a data output node at which a read data signal is provided and a write data signal is received; and a resistive termination circuit having resistive terminations coupled to the data strobe node and the output nodes and further having a strobe termination activation node at which a first control signal is applied and an I/O termination activation node at which a second control signal is applied, the resistive termination circuit configured to enable the resistive terminations coupled to the data strobe node in response to the first control signal and enable the resistive terminations coupled to the data output nodes in response to the second control signal. 9. The output buffer of claim 8, further comprising a control circuit having a first logic circuit having input nodes at which the a termination mode select signal and a termination control signal are applied and further having an output node coupled to the strobe termination activation node, the first logic circuit configured to generate an active first control signal in response to a first or second state of the termination mode select signal and an active termination control signal; and a second logic circuit having input nodes at which the termination mode select signal and the termination control signal are applied and further having an output node coupled to the output termination activation node, the second logic circuit configured to generate an active second control signal in response to the first state of the termination mode select signal and the active termination control signal and generate an inactive second control signal in response to the second state of the termination mode select signal and the active termination control signal. 10. The output buffer of claim 9 wherein the plurality of data buffer circuits comprises at least one data buffer circuit including a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the data output node in response to the test control signal. 11. The output buffer of claim 10, further comprising test logic circuit having an input node at which the termination mode select signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the termination mode select signal. 12. The output buffer of claim 8 wherein the resistive terminations of the resistive termination circuits comprise: a pair of series coupled resistors; a first switch coupled to a first of the pair of series coupled resistors and a voltage supply and having a control node coupled to at least one of the strobe and output termination activation nodes; and a second switch coupled to a second of the pair of series coupled resistors and ground and having a control node coupled to at least one of the strobe and output termination activation nodes, the first and second switches selectively coupling the pair of series coupled resistors between the voltage supply and ground. 13. A memory device, comprising: an address bus; a control bus; a data bus; an address decoder coupled to the address bus; a read/write circuit coupled to the data bus; a control circuit coupled to the control bus; a memory-cell array coupled to the address decoder, control circuit, and read/write circuit; and an output buffer coupled to the data bus and the control circuit, the output buffer comprising: a plurality of buffer circuits, each buffer circuit having an input circuit and an output circuit, and further having an on-die termination (ODT) circuit coupled to the input and output circuits, the ODT circuit having an activation node to which an ODT activation signal is coupled to enable and disable the ODT circuit; and an ODT control circuit coupled to the plurality of buffer circuits and having an ODT mode select node to which an ODT mode select signal is applied and an ODT control node to which an ODT control signal is applied, in response to a first state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for the plurality of buffer circuits, and in response to a second state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for a first set of the plurality of buffer circuits and an inactive ODT signal for a second set of the plurality of buffers circuit. 14. The memory device of claim 13 wherein the ODT control circuit of the output buffer comprises: a first logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the first set of the plurality of buffer circuits, the first logic circuit configured to generate an active ODT activation signal for the first set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal; and a second logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the second set of the plurality of buffer circuits, the second logic circuit configured to generate an inactive ODT activation signal for the second set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal. 15. The memory device of claim 13 wherein the second set of the plurality of buffer circuits of the output buffer comprises at least one buffer circuit having a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the output circuit in response to the test control signal. 16. The memory device of claim 15, further comprising a test logic circuit having an input node at which the ODT mode signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the ODT mode select signal. 17. The memory device of claim 13 wherein the first set of the plurality of buffer circuits of the output buffer comprises a set of buffer circuits coupled to receive data strobe signals and the second set of the plurality of buffer circuits comprises a set of buffer circuits coupled to receive data signals. 18. The memory device of claim 13, further comprising a buffer control circuit coupled to the plurality of buffer circuits, the buffer control circuit having a first logic circuit configured to enable the output circuits of the first set of the plurality of buffer circuits responsive to an output enable (OE) control signal and further having a second logic circuit configured to enable the output circuits of the second set of the plurality of buffer circuits responsive to the OE control signal. 19. The memory device of claim 13 wherein the ODT circuit of the output buffer comprises: a pair of series coupled impedance devices; a first switch coupled to a first of the pair of series coupled impedance devices and a voltage supply and having a control node coupled to the activation node; and a second switch coupled to a second of the pair of series coupled impedance devices and ground and having a control node coupled to the activation node, the first and second switches selectively coupling the pair of series coupled impedance devices between the voltage supply and ground responsive the ODT activation signal. 20. A memory device, comprising: an address bus; a control bus; a data bus; an address decoder coupled to the address bus; a read/write circuit coupled to the data bus; a control circuit coupled to the control bus; a memory-cell array coupled to the address decoder, control circuit, and read/write circuit; and an output buffer coupled to the data bus and the control circuit, the output buffer comprising: at least one data strobe buffer circuit having an data strobe node at which a read strobe signal is provided and a write strobe signal is received; a plurality of data buffer circuits, each having a data output node at which a read data signal is provided and a write data signal is received; and a resistive termination circuit having resistive terminations coupled to the data strobe node and the output nodes and further having a strobe termination activation node at which a first control signal is applied and an output termination activation node at which a second control signal is applied, the resistive termination circuit configured to enable the resistive terminations coupled to the data strobe node in response to the first control signal and enable the resistive terminations coupled to the output nodes in response to the second control signal. 21. The memory device of claim 20, further comprising a termination control circuit having a first logic circuit having input nodes at which the a termination mode select signal and a termination control signal are applied and further having an output node coupled to the strobe termination activation node, the first logic circuit configured to generate an active first control signal in response to a first or second state of the termination mode select signal and an active termination control signal; and a second logic circuit having input nodes at which the termination mode select signal and the termination control signal are applied and further having an output node coupled to the output termination activation node, the second logic circuit configured to generate an active second control signal in response to the first state of the termination mode select signal and the active termination control signal and generate an inactive second control signal in response to the second state of the termination mode select signal and the active termination control signal. 22. The memory device of claim 21 wherein the plurality of data buffer circuits of the output buffer comprises at least one data buffer circuit including a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the data output node in response to the test control signal. 23. The memory device of claim 22, further comprising test logic circuit having an input node at which the termination mode select signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the termination mode select signal. 24. The memory device of claim 20 wherein the resistive terminations of the resistive termination circuits comprise: a pair of series coupled resistors; a first switch coupled to a first of the pair of series coupled resistors and a voltage supply and having a control node coupled to at least one of the strobe and output termination activation nodes; and a second switch coupled to a second of the pair of series coupled resistors and ground and having a control node coupled to at least one of the strobe and output termination activation nodes, the first and second switches selectively coupling the pair of series coupled resistors between the voltage supply and ground. 25. A computer system, comprising: a data input device; a data output device; a processor coupled to the data input and output devices; and a memory device coupled to the processor, the memory device comprising, an address bus; a control bus; a data bus; an address decoder coupled to the address bus; a read/write circuit coupled to the data bus; a control circuit coupled to the control bus; a memory-cell array coupled to the address decoder, control circuit, and read/write circuit; an output buffer coupled to the data bus and the control circuit, the output buffer comprising: a plurality of output buffer circuits, each buffer circuit having an input circuit and an output circuit, and further having an on-die termination (ODT) circuit coupled to the input and output circuits, the ODT circuit having an activation node to which an ODT activation signal is coupled to enable and disable the ODT circuit; and an ODT control circuit coupled to the plurality of buffer circuits and having an ODT mode select node to which an ODT mode select signal is applied and an ODT control node to which an ODT control signal is applied, in response to a first state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for the plurality of buffer circuits, and in response to a second state of the ODT mode select signal and an active ODT control signal, the ODT control circuit configured to generate an active ODT activation signal for a first set of the plurality of buffer circuits and an inactive ODT signal for a second set of the plurality of buffers circuit. 26. The computer system of claim 25 wherein the ODT control circuit of the output buffer comprises: a first logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the first set of the plurality of buffer circuits, the first logic circuit configured to generate an active ODT activation signal for the first set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal; and a second logic circuit having input nodes at which the ODT mode select signal and the ODT control signal are applied and further having an output node coupled to the activation nodes of the second set of the plurality of buffer circuits, the second logic circuit configured to generate an inactive ODT activation signal for the second set of the plurality of buffer circuits in response to the second state of the ODT mode select signal and an active ODT control signal. 27. The computer system of claim 25 wherein the second set of the plurality of buffer circuits of the output buffer comprises at least one buffer circuit having a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the output circuit in response to the test control signal. 28. The computer system of claim 27 wherein the memory device further comprises a test logic circuit having an input node at which the ODT mode signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the ODT mode select signal. 29. The computer system of claim 25 wherein the first set of the plurality of buffer circuits of the output buffer comprises a set of buffer circuits coupled to receive data strobe signals and the second set of the plurality of buffer circuits comprises a set of buffer circuits coupled to receive data signals. 30. The computer system of claim 25 wherein the memory device further comprises a buffer control circuit coupled to the plurality of buffer circuits, the buffer control circuit having a first logic circuit configured to enable the output circuits of the first set of the plurality of buffer circuits responsive to an output enable (OE) control signal and further having a second logic circuit configured to enable the output circuits of the second set of the plurality of buffer circuits responsive to the OE control signal. 31. The computer system of claim 25 wherein the ODT circuit of the output buffer comprises: a pair of series coupled impedance devices; a first switch coupled to a first of the pair of series coupled impedance devices and a voltage supply and having a control node coupled to the activation node; and a second switch coupled to a second of the pair of series coupled impedance devices and ground and having a control node coupled to the activation node, the first and second switches selectively coupling the pair of series coupled impedance devices between the voltage supply and ground responsive the ODT activation signal. 32. A computer system, comprising: a data input device; a data output device; a processor coupled to the data input and output devices; and a memory device coupled to the processor, the memory device comprising, an address bus; a control bus; a data bus; an address decoder coupled to the address bus; a read/write circuit coupled to the data bus; a control circuit coupled to the control bus; a memory-cell array coupled to the address decoder, control circuit, and read/write circuit; an output buffer coupled to the data bus and the control circuit, the I/O buffer comprising: at least one data strobe buffer circuit having an data strobe node at which a read strobe signal is provided and a write strobe signal is received; a plurality of data buffer circuits, each having a data output node at which a read data signal is provided and a write data signal is received; and a resistive termination circuit having resistive terminations coupled to the data strobe node and the data output nodes and further having a strobe termination activation node at which a first control signal is applied and an output termination activation node at which a second control signal is applied, the resistive termination circuit configured to enable the resistive terminations coupled to the data strobe node in response to the first control signal and enable the resistive terminations coupled to the data output nodes in response to the second control signal. 33. The computer system of claim 32 wherein the memory device further comprises a termination control circuit having a first logic circuit having input nodes at which the a termination mode select signal and a termination control signal are applied and further having an output node coupled to the strobe termination activation node, the first logic circuit configured to generate an active first control signal in response to a first or second state of the termination mode select signal and an active termination control signal; and a second logic circuit having input nodes at which the termination mode select signal and the termination control signal are applied and further having an output node coupled to the output termination activation node, the second logic circuit configured to generate an active second control signal in response to the first state of the termination mode select signal and the active termination control signal and generate an inactive second control signal in response to the second state of the termination mode select signal and the active termination control signal. 34. The computer system of claim 33 wherein the plurality of data buffer circuits of the output buffer comprises at least one data buffer circuit including a test circuit having a test control node at which a test control signal is applied and further having a test input node to which a test input signal is applied, the test circuit configured to couple the test input node to the data output node in response to the test control signal. 35. The computer system of claim 34 wherein the memory device further comprises test logic circuit having an input node at which the termination mode select signal is applied and an output coupled to the test control node of the buffer circuit having the test circuit to enable the test circuit in response to the second state of the termination mode select signal. 36. The computer system of claim 32 wherein the resistive terminations of the resistive termination circuits comprise: a pair of series coupled resistors; a first switch coupled to a first of the pair of series coupled resistors and a voltage supply and having a control node coupled to at least one of the strobe and output termination activation nodes; and a second switch coupled to a second of the pair of series coupled resistors and ground and having a control node coupled to at least one of the strobe and output termination activation nodes, the first and second switches selectively coupling the pair of series coupled resistors between the voltage supply and ground. 37. A method of configuring on-die terminations (ODTs) for a plurality of output buffer circuits, comprising: in a first mode, enabling and disabling the ODTs for the plurality of output buffer circuits in response to an ODT control signal; and in a second mode, disabling at least one ODT for a first set of the plurality of output buffer circuits and enabling and disabling the ODTs for a second set of the plurality of output buffer circuits in response to the ODT control signal. 38. The method of claim 37 wherein disabling the ODTs for the first set of the plurality of output buffer circuits comprises disabling the ODTs for a set of data buffer circuits and enabling and disabling the ODTs for the second set of the plurality of output buffer circuits comprises enabling and disabling the ODTs for a set of data strobe buffer circuits. 39. The method of claim 37 wherein enabling and disabling the ODTs for the plurality of output buffer circuits comprises coupling a pair of series-coupled impedance devices to a voltage supply and ground. 40. The method of claim 37 wherein the first mode comprises a normal operating mode and the second mode comprises a test mode. 41. The method of claim 37, further comprising enabling a test mode of the I/O buffer having the disabled ODT in the second mode. 42. A method of controlling termination circuits of data strobe and data buffer circuits, comprising: enabling and disabling the termination circuit of the data strobe buffer circuit in response to a set of control signals; and enabling and disabling the termination circuits of at least one of the data buffer circuits in response to the set of control signals, the termination circuit of the data strobe buffer circuit not responding identically as the termination circuits of the data buffer circuits in response to the set of control signals. 43. The method of claim 42 wherein enabling and disabling the termination circuits of the data strobe and data buffer circuits comprises coupling a pair of series-coupled impedance devices to a voltage supply and ground. 44. The method of claim 42 wherein enabling and disabling the termination circuit of the data strobe buffer circuit comprises enabling and disabling the termination circuit of the data strobe buffer responsive to an activation signal for a first state of the set of control signals and for a second state of the set of control signals, and enabling and disabling the termination circuit of the data buffer circuit responsive to the activation signal for the first state of the set of control signals and disabling the termination circuit of the data buffer circuit for the second state of the set of control signals. 45. The method of claim 42, further comprising enabling a test mode for the data buffer circuit in response to the second state of the set of control signals. 46. The method of claim 42 wherein enabling and disabling the termination circuit of the data strobe buffer circuit in response to a set of control signals comprises providing the set of control signals to a first logic circuit and enabling and disabling the termination circuits of at least one of the data buffer circuits in response to the set of control signals comprises providing the set of control signals to a second logic circuit. | TECHNICAL FIELD The present invention relates generally to semiconductor memory devices, and more specifically, to memory devices having independent control of on-die termination circuits of buffer circuits, such as data strobe and data buffers. BACKGROUND OF THE INVENTION Memory devices are typically assembled into memory modules that are used in a computer system. These memory modules typically include single in-line memory modules (SIMMs) having memory devices on one side of the memory module, and dual in-line memory modules (DIMMs) having memory devices on both sides of the memory module. The memory devices of a memory module are accessed in groups. Each of the groups are commonly referred to as “ranks,” with single-sided DIMMs typically having one rank of memory devices and double-sided DIMMs having two ranks of memory devices, one rank on either side of the memory module. Each of the memory devices of a memory module receives a set of signals which is generated by a memory controller to command the memory devices to perform various memory operations. For example, these signals include a clock signal for synchronizing the timing of the memory operations with the memory controller, command signals to direct the memory devices to perform specific memory operations, and address signals to identify a memory location in the memory devices. Additionally, the memory controller can send write data signals for data that are written to the memory device, and write strobe signals for signaling to the memory device the time at which write data is provided to the memory devices by the memory controller. The memory controller also receives signals from the memory devices of a memory module, such as read data signals for data that are retrieved from the memory devices and read strobe signals for signaling to the controller the time at which read data are provided to the memory controller by the memory devices. As the clock frequencies increase for the memory systems in which the memory devices and memory modules operate, timing and voltage margins for the various signals related to memory device operation become more critical. Subtle variations in signal timing and operating conditions can negatively impact memory device performance. Consequently, it is desirable to improve timing and voltage margins without sacrificing performance, where possible. An example of an approach to improving timing and voltage margins is the use of on-die terminations (ODT) for input/output buffers, such as data strobe, data, and data mask buffers of the memory devices. The ODT circuits provide resistive terminations that improve voltage margin and signal integrity for both read and write operations. The improved voltage margin also indirectly provides improved timing margin in that the time for which data is valid is increased with the use of ODT. As a result, the “data eye” for memory devices having ODT are generally larger than for memory devices without ODT, which enable systems having these memory devices to attain higher data rates. The ODT for conventional memory devices are typically enabled and disabled for a memory device using an ODT control signal provided to the memory devices by a memory controller. With the ODT control signal active, the ODT for the data strobe buffers, the data buffers, and the data mask buffers are enabled to provide resistive termination, and with the ODT control signal inactive, the ODT for all of the buffers are disabled. Thus, the ODT control signal can be used by the memory controller to turn the ODT of a rank of memory on and off as needed. For example, in a memory module having a single rank of memory devices, the ODT is typically enabled for write operations, but disabled for read operations. Having control over the activation of the ODT of the rank of memory devices also allows for a preferred operating condition for writing data to a rank of memory devices in a memory system having at least two ranks of memory devices. The preferred condition is to disable the ODT for the rank of memory devices of the memory module to which data is being written and enable the ODT for the rank of memory devices of the memory module to which data is not being written. Thus, to setup this condition, the memory controller provides an active ODT control signal to the rank of memory devices not being accessed and an inactive ODT control signal to the rank of memory devices being accessed. Another approach to improving signal timing margins is to calibrate the timing of various signals between a memory controller and the memory devices of a memory system. The signals that are received and provided by the memory controller and the memory devices of the memory module are coupled to signal lines that extend between the memory controller and the memory devices. Some signals are provided and received in parallel by each of the memory devices of the memory module and the memory controller over respective sets of parallel signals lines. These type of signals include data signals (both read and write) and strobe signals (both read and write). Each of the memory devices, at least for one rank, receives and provides data and strobe signals over its own set of signal lines that are coupled to the memory controller. In contrast, other signals are provided using a common signal line. For example, a clock signal provided by the memory controller to the memory devices of a memory module having a “fly-back” arrangement share a common clock signal line to which each of the memory devices are coupled. In laying out the signal lines of a memory module that are coupled to the memory controller and the memory devices, it is generally the case that many of the signal lines will have different lengths. These different lengths can cause timing skews between the signals that are provided in parallel to the memory devices and the memory controller, such as data signals and strobe signals. As a result, data being written to the memory devices can arrive to each of the memory devices at slightly different times although the data is coupled to the respective signal lines by the memory controller simultaneously. Similarly, read data from each of the memory devices of a memory module can arrive at the memory controller at slightly different times although the memory devices couple the respective read data to the signal lines simultaneously. Additionally, due to propagation delays of a signal line, a time difference at which a signal is received along the length of the signal line will result. Thus, a signal, such as a clock signal, that is provided to the memory devices of a memory module over a shared signal line will be received by each of the memory devices at slightly different times, depending on where along the length of the signal line the respective memory device is coupled. These timing skews that are created between signals and over the length of a signal line may be only several picoseconds long. However, in high-speed memory systems, several picoseconds can significantly reduce the timing margin of signals. As the timing margin of signals decreases, subtle timing variations caused by other factors, such as variations and drifts in power, voltage, and temperature, may result in memory errors. Moreover, the timing of the signals provided to the memory devices by the memory controller can be skewed relative to one another because of the length of the signal lines and the manner in which the signal is provided to the memory devices. For example, it is desirable for write strobe signals to be aligned with the clock signal as received by each of the memory devices. However, as previously mentioned, the strobe signals are typically provided to each of the memory devices on parallel sets of signal lines, whereas the clock signal is provided to each memory device on a common signal line. In this arrangement, the relative timing of the clock signal and the write strobe signal for each of the memory devices may be different due to the propagation delay of the clock signal on the common signal line. That is, not only are the write strobe signals be skewed from the clock signal, it is possible for the amount of timing skew to be different for each of the memory devices. As a result, the timing margin for signals may be further reduced by the timing skew of the different types of signals provided to the memory devices on signal lines having different arrangements. An approach to addressing the problems of reduced timing margin due to timing skew between signals and between the memory devices of a memory module is to calibrate the relative timing of the signals to each of the memory devices in order to compensate for the timing differences. “Pre-skewing” the timing of signals, for example, by selectively delaying the time at which the respective signals are provided by the memory controller to each of the respective memory devices, can compensate for the timing skew inherent in the memory system. Additionally, periodically performing calibration can be used to compensate for timing drift. A specific proposal for write data strobe to clock calibration for the ranks of memory devices of a memory system has been proposed. In performing the “write levelization,” a memory controller provides the clock signal and a write strobe to each of the memory devices of a rank. The memory devices are each equipped with a SR-latch having the clock signal applied to a set-input and clocked by the respective write strobe signal. The output signal of the SR-latch is provided back to the memory controller as a data signal, which is then used by the memory controller to adjust a time delay for when the write strobe is provided to the rank of memory devices. In this manner, the delay can be adjusted until the write strobe and the clock signal are aligned, as received by the respective memory devices of a rank of memory. In practicing the write levelization process with conventional memory devices, a problem results for memory systems having more than one rank of memory devices. As previously discussed, the preferred operating condition for performing a write operation to a rank of memory devices is to disable the ODT for the rank of memory devices being accessed and enable the ODT for the rank of memory devices not being accessed. Typically, an inactive ODT control signal is provided to the rank of memory devices being accessed to disable the ODT for the data strobe, data, and data mask buffers, and an active ODT control signal is provided to the rank of memory devices not being accessed to enable the ODT for the data strobe, data, and data mask buffers. As previously discussed, the write levelization process requires, however, that a write strobe signal is provided to the memory device to clock a SR-latch, and the output of the SR-latch is provided back to the memory controller, preferably, as a data signal. To accurately simulate write operating conditions, and consequently obtain accurate write levelization, the ODT for the data strobe buffer of the rank of memory devices not being accessed should be enabled, while the ODT for the data buffer for the same rank of memory devices should be disabled to provide the SR-latch output signal back to the memory controller. This preferred condition cannot be set using conventional memory devices having ODT because although the ODT for a memory device can be enabled and disabled using the ODT control signal, the ODT for the data strobe, data, and data mask buffers are enabled and disabled together. Thus, the ODT for the data strobe buffers cannot be enabled while the ODT for the data buffers are disabled, and vice-versa. SUMMARY OF THE INVENTION One aspect of the present invention provides an input/output (I/O) buffer that includes on-die terminations (ODTs) that can be enabled and disabled for a first set buffer circuits independently from the ODTs for a second set of the buffer circuits. Another aspect of the invention provides that the ODTs for the buffer circuits of an I/O buffer can be enabled and disabled in response to an ODT control signal, and additionally, the ODTs for a first set of the buffer circuits can be enabled and disabled responsive to the ODT control signal while the ODT for at least one of a second set of the buffer circuits is disabled. In another aspect of the invention, the ODT for at least one data buffer circuit can be disabled while the ODT for a data strobe buffer circuit can be enabled and disabled responsive to a control signal. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a functional block diagram of a synchronous memory device in which an embodiment of the present invention is implemented. FIG. 2 is a schematic block diagram of an output enable control circuit and an input/output buffer according to an embodiment of the present invention. FIG. 3 is a functional diagram of an on-die termination circuit of the input/output buffer of FIG. 2. FIG. 4 is a schematic block diagram of a SR-latch and control logic that can be used with embodiments of the present invention for write levelization. FIG. 5 is a functional diagram of a memory controller and a memory device of a single rank memory system on which write levelization is performed. FIG. 6 is a functional diagram of a memory controller and two memory devices, each representing a different rank of memory devices, where write levelization is performed on one of the ranks of memory devices. FIG. 7 is a functional block diagram illustrating a computer system including a synchronous memory device in which an embodiment of the present invention is included. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Certain details are set forth below to provide a sufficient understanding of the invention. However, it will be clear to one skilled in the art that the invention may be practiced without these particular details. In other instances, well-known circuits, control signals, timing protocols, and software operations have not been shown in detail in order to avoid unnecessarily obscuring the invention. FIG. 1 illustrates a memory device in which an embodiment of the present invention is implemented. The memory device 100 in FIG. 1 is a double-data rate (DDR) synchronous dynamic random access memory (“SDRAM”). The memory device 100 is referred to as a double-data-rate device because the data words DQ being transferred to and from the device are transferred at double the rate of a conventional SDRAM, which transfers data at a rate corresponding to the frequency of the applied clock signal. However, the principles described herein are applicable to any memory device that may include a delay-locked loop for synchronizing internal and external signals, such as' conventional synchronous DRAMs (SDRAMs), as well as packetized memory devices like SLDRAMs and RDRAMs, and are equally applicable to any integrated circuit that must synchronize internal and external clocking signals. The memory device 100 includes an address register 102 that receives row, column, and bank addresses over an address bus ADDR, with a memory controller (not shown) typically supplying the addresses. The address register 102 receives a row address and a bank address that are applied to a row address multiplexer 104 and bank control logic circuit 106, respectively. The row address multiplexer 104 applies either the row address received from the address register 102 or a refresh row address from a refresh counter 108 to a plurality of row address latch and decoders 110A-D. The bank control logic 106 activates the row address latch and decoder 110A-D corresponding to either the bank address received from the address register 102 or a refresh bank address from the refresh counter 108, and the activated row address latch and decoder latches and decodes the received row address. In response to the decoded row address, the activated row address latch and decoder 110A-D applies various signals to a corresponding memory bank 112A-D to thereby activate a row of memory cells corresponding to the decoded row address. Each memory bank 112A-D includes a memory-cell array having a plurality of memory cells arranged in rows and columns, and the data stored in the memory cells in the activated row is stored in sense amplifiers in the corresponding memory bank. The row address multiplexer 104 applies the refresh row address from the refresh counter 108 to the decoders 110A-D and the bank control logic circuit 106 uses the refresh bank address from the refresh counter when the memory device 100 operates in an auto-refresh or self-refresh mode of operation in response to an auto- or self-refresh command being applied to the memory device 100, as will be appreciated by those skilled in the art. A column address is applied on the ADDR bus after the row and bank addresses, and the address register 102 applies the column address to a column address counter and latch 114 which, in turn, latches the column address and applies the latched column address to a plurality of column decoders 116A-D. The bank control logic 106 activates the column decoder 116A-D corresponding to the received bank address, and the activated column decoder decodes the applied column address. Depending on the operating mode of the memory device 100, the column address counter and latch 114 either directly applies the latched column address to the decoders 116A-D, or applies a sequence of column addresses to the decoders starting at the column address provided by the address register 102. In response to the column address from the counter and latch 114, the activated column decoder 116A-D applies decode and control signals to an I/O gating and data masking circuit 118 which, in turn, accesses memory cells corresponding to the decoded column address in the activated row of memory cells in the memory bank 112A-D being accessed. During data read operations, data being read from the addressed memory cells are coupled through the I/O gating and data masking circuit 118 to a read latch 120. The I/O gating and data masking circuit 118 supplies N bits of data to the read latch 120, which then applies four N/4 bit words to a multiplexer 122. In the embodiment of FIG. 3, the circuit 118 provides 8 bits to the read latch 120 which, in turn, provides four 4 bits words to the multiplexer 122. An I/O buffer 124 sequentially receives the N/4 bit words from the multiplexer 122 and also receives a data strobe signal DQS from a strobe signal generator 126 and a delayed clock signal CLKDEL from the delay-locked loop (DLL) 127. The I/O buffer 124 includes output buffer circuits (not shown) that have output circuits to generate output signals from the memory device 100 and input buffer circuits (not shown) to receive input signals to the memory device 100. The buffer circuits further include on-die termination (ODT) circuitry (not shown) to provide resistive termination for the buffer circuits. An output enable (OE) control 125 is used to configure the I/O buffer 124 in accordance with various signals, such as flag bits of a mode register 135, an external ODT control signal, and internal control signals. In response, the OE control 125 generates signals that set the I/O buffer 124 in different configurations, for example, enabling and disabling the ODT circuitry for the output buffers and input buffers of the I/O buffer 124. As will be explained in more detail below, the mode register 135 can be used for storing flag bits that are used to set various modes of operation of the memory device 100. The DQS signal is used by an external circuit such as a memory controller (not shown) for synchronizing receipt of read data during read operations. In response to the delayed clock signal CLKDEL, the I/O buffer 124 sequentially outputs the received N/4 bits words as a corresponding data word DQ, each data word being output in synchronism with rising and falling edges of a CLK signal that is applied to clock the memory device 100. The I/O buffer 124 also outputs the data strobe signal DQS having rising and falling edges in synchronism with rising and falling edges of the CLK signal, respectively. Each data word DQ and the data strobe signal DQS collectively define a data bus DATA. The DATA bus also includes masking signals DM0-M, which will be described in more detail below with reference to data write operations. During data write operations, an external circuit such as a memory controller (not shown) applies N/4 bit data words DQ, the strobe signal DQS, and corresponding data masking signals DM on the data bus DATA. The I/O buffer 124 receives each DQ word and the associated DM signals, and applies these signals to input registers 130 that are clocked by the DQS signal. In response to a rising edge of the DQS signal, the input registers 130 latch a first N/4 bit DQ word and the associated DM signals, and in response to a falling edge of the DQS signal the input registers latch the second N/4 bit DQ word and associated DM signals. The input register 130 provides the four latched N/4 bit DQ words as an N-bit word to a write FIFO and driver 132, which clocks the applied DQ word and DM signals into the write FIFO and driver in response to the DQS signal. The DQ word is clocked out of the write FIFO and driver 132 in response to the CLK signal, and is applied to the I/O gating and masking circuit 118. The I/O gating and masking circuit 118 transfers the DQ word to the addressed memory cells in the accessed bank 112A-D subject to the DM signals, which may be used to selectively mask bits or groups of bits in the DQ words (i.e., in the write data) being written to the addressed memory cells. A SR-latch 129 is also coupled to the I/O buffer 124 to provide write strobe signal to clock signal calibration capability if desired. As previously discussed, when the calibration, or write levelization, is performed, a write strobe signal received by the I/O buffer 124 is used to clock the SR-latch 129, and a clock signal, represented by the output of a clock receiver 131, is coupled to the set-input. The output signal of the SR-latch 129 is coupled to the I/O buffer 124 for provision to a memory controller as a data signal. A control logic and command decoder 134 receives a plurality of command and clocking signals over a control bus CONT, typically from an external circuit such as a memory controller (not shown). The command decoder 134 includes the mode register 135. The command signals include a chip select signal CS#, a write enable signal WE#, a column address strobe signal CAS#, and a row address strobe signal RAS#, while the clocking signals include a clock enable signal CKE# and complementary clock signals CLK, CLK#, with the “#” designating a signal as being active low. The command signals CS#, WE#, CAS#, and RAS# are driven to values corresponding to a particular command, such as a read, write, or auto-refresh command. In response to the clock signals CLK, CLK#, the command decoder 134 latches and decodes an applied command, and generates a sequence of clocking and control signals that control the components 102-132 to execute the function of the applied command. One example of the control signals, as shown in FIG. 1, is a READ signal having a logic level indicative of whether a read command has been received which is generated by the command decoder 134. The clock enable signal CKE enables clocking of the command decoder 134 by the clock signals CLK, CLK#. The command decoder 134 latches command and address signals at positive edges of the CLK, CLK# signals (i.e., the crossing point of CLK going high and CLK# going low), while the input registers 130 and data drivers 124 transfer data into and from, respectively, the memory device 100 in response to both edges of the data strobe signal DQS and thus at double the frequency of the clock signals CLK, CLK#. This is true because the DQS signal has the same frequency as the CLK, CLK# signals. The detailed operation of the control logic and command decoder 134 in generating the control and timing signals is conventional, and thus, for the sake of brevity, will not be described in more detail. FIG. 2 illustrates a portion of an OE control logic 200 and an output buffer 250 according to embodiments of the present invention. The OE control logic 200 can be substituted for the OE control logic 125 and the output buffer 250 can be included in the I/O buffer 124 of FIG. 1. As will be explained in more detail below, the OE logic control 200 and the output buffer 250 provide for the ODT of different sets of buffer circuits of the output buffer 250 to be enabled or disabled independently. The OE control logic 200 receives a READ signal having a logic state indicative of whether a read operation is being executed and further receives an ODT signal having a logic state indicative of whether the ODT of the output buffer 250 should be enabled. The OE control logic 200 is also coupled to the mode register 135. As previously discussed, the mode register 135 stores flag bits that allow the memory device 100 to be set various modes of operation. Two flag bits of the mode register 135 set modes of operation related to the OE control logic 200, namely, an output enable flag bit which can be set to enable or disable output operation of the output buffer 250, and an ODT mode flag bit which can be set to allow for the ODT of different sets of buffers of the output buffer 250 to be enabled or disabled independently. As shown in FIG. 2, the output enable flag bit is bit EM<12> and the ODT mode flag bit is bit EM<7> of the mode register 135. It will be appreciated by those ordinarily skilled in the art that the specific bit used as the output enable and ODT mode flag bits can be changed without departing from the scope of the present invention. The OE control logic 200 further includes data strobe buffer control logic 204, data strobe ODT control logic 208, data buffer control logic 212, and data buffer ODT control logic 216. The control logic 204, 208, 212, 216 provide control signals GQES, GODTQS, GQED, and GODT, respectively. The output buffer 250 is shown in FIG. 2 as including data strobe buffer circuits 254, 258, and data buffer circuits 262, 266. Although not shown in detail, the buffer circuits 254, 258, 262, 266 include output circuits to generate output signals from the memory device 100 and input circuits to receive input signals to the memory device 100. The output circuits are enabled for read operations and the input circuits are enabled for write operations. Conventional output and input circuits known in the art, or later developed, can be used in the buffer circuits 254, 258, 262, 266. The buffer circuits 254, 258, 262, 266 are configured to operate in a test mode when an active testOutEN signal is received. In the test mode, the respective buffer circuits 254, 258, 262, 266 will couple the signal applied to a test-data input to the output. The data strobe buffer and data buffer circuits 254, 258, 262, 266 further include ODT capability to provide resistive terminations. FIG. 3 illustrates a functional drawing of a buffer circuit 300 according to an embodiment of the present invention that includes ODT capability. The buffer circuit 300 includes ODT impedance devices, shown in FIG. 3 as resistors 304, 308, that are coupled in series with ODT switches 312, 316 between a voltage supply having a data high voltage level VddQ and a voltage supply having a data low voltage level VssQ. The ODT switches 312, 316 are controlled by a GODT signal and couple the ODT resistors 304, 308 across the VddQ and VssQ voltage levels to provide resistive termination for the buffer circuit 300. As shown in FIG. 3, the ODT is available for both read data, provided by the output driver 320, and for write data, received by the receiver 324. It will be appreciated by those ordinarily skilled in the art, however, that alternative arrangements for the ODT can be utilized as well without departing from the scope of the present invention. For example, the ODT can use impedance devices such as transistors to replace or supplement the resistors shown in FIG. 3. With reference to FIG. 2, the data strobe buffer circuits 254 and 258 are the buffer circuits for the data strobe signal DQS and the complementary data strobe signal DQS#, respectively, and are coupled to the data strobe buffer control logic 204 and the data strobe ODT control logic 208. The data strobe buffer circuits 254, 258 are further coupled to the DQS generator 126 (FIG. 1) to receive the DQS and DQS# signals. The data buffer circuits 262 and 266 are the buffer circuits for data signals DQ0 and DQ1. Additional data buffer circuits, not shown in FIG. 2, can be included in the output buffer 250, with the total number of data buffer circuits corresponding to the data width of the memory device 100. The data buffer circuits 262, 266 are coupled to the data buffer control logic 212 and the data buffer ODT control logic 216, and are further coupled to the multiplexer 122 (FIG. 1) to receive read data retrieved from the memory arrays 112A-D. In the embodiment shown in FIG. 2, the output buffer 250 further includes write strobe synchronization logic 270 coupled to the data buffer circuit 262, which corresponds to the data buffer circuit for DQ0. In alternative embodiments, the write strobe synchronization logic 270 can be coupled to a different data buffer circuit included in the output buffer 250, and thus, the scope of the present invention is not limited to having the data buffer circuit for DQ0 coupled to the strobe synchronization logic 270. As will be explained in more detail below, the write strobe synchronization logic 270 can be included in the output buffer 250 where write levelization between a memory controller and the memory device 100 is desirable. The ODT of the buffer circuits 254, 258, 262, and 266 can be enabled or disabled under the control of the ODT signal, which is typical during normal operation of the memory device 100. Under normal operation, the output enable flag bit EM<12> is set LOW to enable output operation of the data strobe and data buffer circuits 254, 258, 262, and 266, and the ODT mode flag bit EM<7> is set LOW to disable the independent operation of the ODT of the data buffer circuits 262, 266. The LOW EM<12> bit results in a LOW DQRST signal and the LOW EM<7> bit results in a LOW DqsCap signal. With the DQRST signal LOW, the data strobe buffer control logic 204 behaves as a signal buffer for a QESen signal, which is provided to the data strobe buffer circuits 254, 258 as a GQES signal. Similarly, the data buffer control logic 212 behaves as a signal buffer for a QEDen signal, which is provided to the data buffer circuits 262, 266 as a GQED signal. The QESen and QEDen signals have logic levels corresponding to the READ signal, and the GQES and GQED signals represent data strobe buffer enable and data buffer enable signals, respectively. Consequently, the GQES and GQED signals have active HIGH logic levels when the READ signal provided by the control logic 134 (FIG. 1) is active, indicating that a read operation has been requested. The GQES and GQED signals in turn activate the output circuits of the respective buffer circuits to output the signal received at the data terminals. That is, the data strobe buffer circuit 254 drives the DQS signal, the data strobe buffer circuit 258 drives the DQS# signal, the data buffer circuit 262 drives the DQ0 signal and the data buffer circuit 266 drives the DQ1 signal. The data strobe ODT control logic 208 and the data ODT control logic 216, with LOW DQRST and DqsCap signals, also behave as signal buffers, with the ODT control logic 208 and the data ODT control logic 216 providing an ODTen signal to the data strobe buffer circuits 254, 258 as a GODTQS signal and to the data buffer circuits 262, 266 as a GODT signal, respectively. The logic level of the ODTen signal, and consequently, the GODTQS and GODT signals, correspond to the logic level of the ODT signal applied to the memory device 100 when the state of operation of the memory device 100 (i.e., read or write operation) is a write state. Thus, the ODTen signal enables and disables the ODT of the buffer circuits 254, 258, 262, and 266 in accordance with the ODT signal during a write operation. As a result, the ODT signal will control activation of the ODT for the data strobe and data buffer circuits 254, 258, 262, and 266. Additionally, the ODT of the data buffer circuits 262, 266 can be disabled independently of the ODT for the data strobe buffer circuits 254, 258. As a result, the ODT for the data strobe buffer circuits 254, 258 can be enabled and disabled using the ODT signal without affecting the state of the ODT for the data buffer circuits 262, 266. When independent control of the ODT for the data strobe buffers circuits 254, 258 and the data buffer circuits 262, 266 is desired, the output enable flag bit EM<12> can remain LOW, but the ODT mode flag bit EM<7> is set HIGH. In this state, the DQRST signal still has a LOW logic state, but the DqsCap signal now has a HIGH logic state. The data strobe buffer control logic 204 and the data buffer control logic 212 operate as previous described, buffering the QESen signal and the QEDen signal, respectively, and provide active GQES and GQED signals when a read operation is requested to activate output circuits of the data strobe and data buffer circuits 254, 258 and 262, 266. Similarly, although the DqsCap signal is HIGH, the data strobe ODT control logic 208 still operates as a signal buffer for the ODTen signal, providing the GODTQS signal to enable and disable the ODT of the data strobe buffer circuits 254, 258. However, the HIGH DqsCap signal causes the GODT signal output by the data ODT control logic 216 to have a LOW logic level, regardless of the logic level of the ODTen signal. Consequently, the ODT for the data buffer circuits 262, 266 are disabled, regardless of the logic level of the ODT signal provided to the memory 100. As a result, activation of the ODT for the data strobe buffer circuits 254, 258 through the use of the ODT signal is now independent from the activation of the ODT for the data buffer circuits 262, 266. In the event the output enable flag bit EM<12> is set HIGH to disable output operation of the buffer circuits 254, 258, 262, 266, the GQES signal provided by the data strobe buffer control logic 204, the GQED signal provided by the data buffer control logic 212, and the GODT signal provided by the data ODT control logic 216 will be LOW, disabling the output circuits of the buffer circuits 254, 258, 262, 266 and disabling the ODT of the data buffer circuits 262, 266. The EM<12> bit is typically used during characterization of operating currents for the memory device 100. In contrast to the GODT signal from the ODT control logic 216, the GODTQS signal provided by the data strobe ODT control logic 208 will have a logic state depending on the state of the ODT mode flag bit EM<7> and the state of the ODT signal. Typically, however, when the EM<12> bit is set HIGH, the EM<7> bit will be set LOW to have normal operation of the ODT for the buffer circuits 254, 258, 262, 266. As a result, the GODTQS signal has a LOW logic level, regardless of the logic level of the ODTen signal, to disable the ODT of the data strobe buffer circuits 254, 258. The independent operation of the ODT for the data strobe buffer circuits 254, 258 and for the data buffer circuits 262, 266 can be utilized in many ways. One such way is for performing write levelization between a memory controller and the memory devices of a memory module. As previously discussed, the process of write levelization is used to deskew a clock signal and a write strobe signal provided to a memory device so that the write strobe is aligned with the clock edges of the clock signal. The skewing of signals, as also previously discussed, can result from the manner in which the respective signals are coupled between the memory controller and the respective memory devices, as well as from inherent line impedances and other propagation delays. Currently, write levelization is performed by providing a clock signal and a write strobe signal to one rank of memory devices of a memory system. As previously discussed, a rank of memory devices generally refers to a group of memory devices that are accessed concurrently. Each of the memory devices of the rank includes a SR-latch that is clocked by the write strobe signal and has the clock signal as the set-input for the latch. The output signals of each of the latches are output by the respective memory devices and fed back to the memory controller. Typically, data terminal DQ0 is used to output the signal fed back to the memory controller. With reference to FIG. 2, the write strobe synchronization logic 270 is included with the output buffer 250 to enable and disable a test-data input for the data buffer circuit 262. As shown in FIG. 2, the write strobe synchronization logic 270 controls whether the test-data input is enabled so that a test-date signal ToutDqsC coupled to the test-data input of the data buffer circuit 262 is output instead of a signal applied to the data input of the data buffer circuit 262. An example of a SR-latch and control logic is illustrated in FIG. 4. External clock and data strobe signals XCLK, XCLK# and DQS, DQS# are coupled to internal buffers 412 and 416, respectively. The buffered clock and data strobe signals are coupled to respective signal drivers 420, 424, which provide the clock and data strobe signals to circuitry in the memory device 100. The buffered clock signal and data strobe signal are coupled to control logic 404. A DqsCap signal, which has a logic level set by flag bit EM<7> (FIG. 2), controls coupling of the clock and data strobe signals output by the internal signal buffers 412, 416 to the set-input and clock input, all respectively, of a SR-latch 408. The output signal ToutDqsC of the SR-latch 408 is coupled to the test-data input of the data buffer circuit 262 to be output by the memory device 100 as DQ0. FIG. 4 illustrates a particular example of control logic and a SR-latch for the purpose of write levelization. However, it will be appreciated by those ordinarily skilled in the art that alternative designs can be used as well. As previously discussed, the output signals of the memory devices are used to adjust a respective time delay at the memory controller by which the write strobe signals output by the memory controller and provided to a respective memory device are delayed. The time delay for each of write strobe signals is adjusted until the respective write strobe signal is aligned with the clock signal, as received by the respective memory devices of a rank of memory on a memory module. Multiple ranks of memory can be on a memory module, but it is typical for have one or two ranks of memory devices per module. Additionally, a memory system can have a plurality of ranks of memory devices, with the ranks arranged in single rank modules and dual rank modules. As will be illustrated by the following examples, the independent ODT control provided by embodiments of the present invention allow for the preferable write levelization conditions to be set for both a single rank memory module and a dual rank memory module. When performing write levelization for the memory devices of a memory system having only one rank of memory devices, the ODTs for the data strobe terminals, DQS and DQS#, of the memory devices are active, while the ODTs for the data terminals, DQ0-DQn, are preferably inactive. Any resistive terminations at the data terminals of the memory controller are enabled. These conditions for write levelization of a single rank memory system are shown in FIG. 5. A memory controller 502 is coupled to a memory device 504, which represents a memory device of the single rank of memory. Output buffers 524, 528 drive a clock signal and a write strobe signal that are coupled to the input buffers 532 and 536 of memory device 504, all respectively. An ODT 508 is activated for the input buffer 536 to provide a resistive termination for the write strobe signal. A SR-latch 520 in the memory device 504 is clocked by the write strobe signal and receives the clock signal as the set-input signal. The output of the SR-latch 520 is provided to an output buffer 540, representing the output buffer for the data terminal DQ0. The output signal from DQ0 is coupled back to an input buffer 544 of the memory controller 502. An ODT 512 is activated for the memory controller to provide a resistive termination for the output signal from DQ0. Although not shown in FIG. 5, the output signal from DQ0 is used to adjust the timing of the write strobe signal output by the memory controller 502 relative to the clock signal. In this manner, the write strobe signal can be pre-skewed so that the write strobe signal and the clock signal are aligned when received by the memory device 504. To set the conditions for write levelization of a rank of memory devices for a memory system having only one rank of memory devices, with reference to FIG. 2, the flag bit EM<7> is set HIGH and the flag bit EM<12> is set LOW to enable independent ODT control and enable the output circuits of the buffer circuits 254, 258, 262, 266. The ODT signal applied to the memory device 100 is HIGH and a write command is issued. Under these conditions the data strobe buffer circuits 254, 258 have the ODT enabled and the input circuits are enabled to receive the write strobe signal, either or both the DQS and DQS# signals, as previously described. Additionally, the ODTs for the data buffer circuits 262, 266 are disabled and the write strobe synchronization logic 270 enables the data buffer circuit 262 to output the ToutDqsC signal applied to the test-data input. With reference to FIG. 4, the DqsCap signal set HIGH by the flag bit EM<7> couples the clock signal and the write strobe signal to the set-input and the clock input of the SR-latch, respectively. The ToutDqsC signal is output from the SR-latch 420 (FIG. 5), which is buffered by the data buffer circuit 262 and coupled back to the memory controller 402 as the DQ0 signal. Write levelization for a rank of memory devices in a memory system having two or more ranks of memory devices is performed under different conditions than previously described for a memory system having only one rank of memory devices. With two or more ranks of memory devices, the preferred condition is to disable the ODT for the rank of memory devices for which write levelization is performed, while setting only the ODT for the data strobe terminals DQS and DQS# of the other ranks of memory devices on which write levelization is not performed. The resistive terminations at the data terminals of the memory controller are enabled, the same as with the write levelization conditions for a single rank memory system. FIG. 6 illustrates the preferred write levelization conditions for a memory system having two or more ranks of memory devices. Where appropriate, the same reference numbers used in FIG. 5 have also been used in FIG. 6. A memory device 604, representing a memory device of a second rank of memory devices, has an ODT 608 enabled for the data strobe terminal, shown as input buffer 536. Although the write levelization is being performed on the first rank of memory devices, represented by the memory device 504, and not being performed on the second rank of memory devices, the ODT 608 of the memory device 604 is enabled. To set the preferred condition for write levelization of a rank of memory devices in a memory system having two or more ranks of memory devices, the memory device 504 has the flag bit EM<7> set HIGH to enable the test mode of the data buffer circuit 262 (through the write strobe synchronization logic 270 (FIG. 2)) and couple the clock signal and the write strobe signal to the SR-latch (FIG. 4). Additionally, the flag bit EM<12> set LOW to enable the output circuits of the buffer circuits 254, 258, 262, 266. However, in contrast to the conditions for write levelization for a rank of memory devices in a single rank memory system, as previously discussed, the ODT signal applied to the memory device 504 is LOW, disabling all of the ODTs for the data strobe and data buffer circuits of the memory device 504. As for the memory device 604, the flag bit EM<7> set HIGH to enable independent ODT control for the data strobe buffer circuits, and the flag bit EM<12> is set HIGH to disable the output circuitry of the buffer circuits 254, 258, 262, 266 of the memory device 604. The ODT signal coupled to the memory device 604 is HIGH in order to enable the ODT for the data strobe buffer circuits 254, 258. FIG. 7 is a block diagram of a computer system 700 including computer circuitry 702 including the memory device 100 of FIG. 1. Typically, the computer circuitry 702 is coupled through address, data, and control buses to the memory device 100 to provide for writing data to and reading data from the memory device. The computer circuitry 702 includes circuitry for performing various computing functions, such as executing specific software to perform specific calculations or tasks. In addition, the computer system 700 includes one or more input devices 704, such as a keyboard or a mouse, coupled to the computer circuitry 702 to allow an operator to interface with the computer system. Typically, the computer system 700 also includes one or more output devices 706 coupled to the computer circuitry 702, such as output devices typically including a printer and a video terminal. One or more data storage devices 708 are also typically coupled to the computer circuitry 702 to store data or retrieve data from external storage media (not shown). Examples of typical storage devices 708 include hard and floppy disks, tape cassettes, compact disk read-only (CD-ROMs) and compact disk read-write (CD-RW) memories, and digital video disks (DVDs). From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Memory devices are typically assembled into memory modules that are used in a computer system. These memory modules typically include single in-line memory modules (SIMMs) having memory devices on one side of the memory module, and dual in-line memory modules (DIMMs) having memory devices on both sides of the memory module. The memory devices of a memory module are accessed in groups. Each of the groups are commonly referred to as “ranks,” with single-sided DIMMs typically having one rank of memory devices and double-sided DIMMs having two ranks of memory devices, one rank on either side of the memory module. Each of the memory devices of a memory module receives a set of signals which is generated by a memory controller to command the memory devices to perform various memory operations. For example, these signals include a clock signal for synchronizing the timing of the memory operations with the memory controller, command signals to direct the memory devices to perform specific memory operations, and address signals to identify a memory location in the memory devices. Additionally, the memory controller can send write data signals for data that are written to the memory device, and write strobe signals for signaling to the memory device the time at which write data is provided to the memory devices by the memory controller. The memory controller also receives signals from the memory devices of a memory module, such as read data signals for data that are retrieved from the memory devices and read strobe signals for signaling to the controller the time at which read data are provided to the memory controller by the memory devices. As the clock frequencies increase for the memory systems in which the memory devices and memory modules operate, timing and voltage margins for the various signals related to memory device operation become more critical. Subtle variations in signal timing and operating conditions can negatively impact memory device performance. Consequently, it is desirable to improve timing and voltage margins without sacrificing performance, where possible. An example of an approach to improving timing and voltage margins is the use of on-die terminations (ODT) for input/output buffers, such as data strobe, data, and data mask buffers of the memory devices. The ODT circuits provide resistive terminations that improve voltage margin and signal integrity for both read and write operations. The improved voltage margin also indirectly provides improved timing margin in that the time for which data is valid is increased with the use of ODT. As a result, the “data eye” for memory devices having ODT are generally larger than for memory devices without ODT, which enable systems having these memory devices to attain higher data rates. The ODT for conventional memory devices are typically enabled and disabled for a memory device using an ODT control signal provided to the memory devices by a memory controller. With the ODT control signal active, the ODT for the data strobe buffers, the data buffers, and the data mask buffers are enabled to provide resistive termination, and with the ODT control signal inactive, the ODT for all of the buffers are disabled. Thus, the ODT control signal can be used by the memory controller to turn the ODT of a rank of memory on and off as needed. For example, in a memory module having a single rank of memory devices, the ODT is typically enabled for write operations, but disabled for read operations. Having control over the activation of the ODT of the rank of memory devices also allows for a preferred operating condition for writing data to a rank of memory devices in a memory system having at least two ranks of memory devices. The preferred condition is to disable the ODT for the rank of memory devices of the memory module to which data is being written and enable the ODT for the rank of memory devices of the memory module to which data is not being written. Thus, to setup this condition, the memory controller provides an active ODT control signal to the rank of memory devices not being accessed and an inactive ODT control signal to the rank of memory devices being accessed. Another approach to improving signal timing margins is to calibrate the timing of various signals between a memory controller and the memory devices of a memory system. The signals that are received and provided by the memory controller and the memory devices of the memory module are coupled to signal lines that extend between the memory controller and the memory devices. Some signals are provided and received in parallel by each of the memory devices of the memory module and the memory controller over respective sets of parallel signals lines. These type of signals include data signals (both read and write) and strobe signals (both read and write). Each of the memory devices, at least for one rank, receives and provides data and strobe signals over its own set of signal lines that are coupled to the memory controller. In contrast, other signals are provided using a common signal line. For example, a clock signal provided by the memory controller to the memory devices of a memory module having a “fly-back” arrangement share a common clock signal line to which each of the memory devices are coupled. In laying out the signal lines of a memory module that are coupled to the memory controller and the memory devices, it is generally the case that many of the signal lines will have different lengths. These different lengths can cause timing skews between the signals that are provided in parallel to the memory devices and the memory controller, such as data signals and strobe signals. As a result, data being written to the memory devices can arrive to each of the memory devices at slightly different times although the data is coupled to the respective signal lines by the memory controller simultaneously. Similarly, read data from each of the memory devices of a memory module can arrive at the memory controller at slightly different times although the memory devices couple the respective read data to the signal lines simultaneously. Additionally, due to propagation delays of a signal line, a time difference at which a signal is received along the length of the signal line will result. Thus, a signal, such as a clock signal, that is provided to the memory devices of a memory module over a shared signal line will be received by each of the memory devices at slightly different times, depending on where along the length of the signal line the respective memory device is coupled. These timing skews that are created between signals and over the length of a signal line may be only several picoseconds long. However, in high-speed memory systems, several picoseconds can significantly reduce the timing margin of signals. As the timing margin of signals decreases, subtle timing variations caused by other factors, such as variations and drifts in power, voltage, and temperature, may result in memory errors. Moreover, the timing of the signals provided to the memory devices by the memory controller can be skewed relative to one another because of the length of the signal lines and the manner in which the signal is provided to the memory devices. For example, it is desirable for write strobe signals to be aligned with the clock signal as received by each of the memory devices. However, as previously mentioned, the strobe signals are typically provided to each of the memory devices on parallel sets of signal lines, whereas the clock signal is provided to each memory device on a common signal line. In this arrangement, the relative timing of the clock signal and the write strobe signal for each of the memory devices may be different due to the propagation delay of the clock signal on the common signal line. That is, not only are the write strobe signals be skewed from the clock signal, it is possible for the amount of timing skew to be different for each of the memory devices. As a result, the timing margin for signals may be further reduced by the timing skew of the different types of signals provided to the memory devices on signal lines having different arrangements. An approach to addressing the problems of reduced timing margin due to timing skew between signals and between the memory devices of a memory module is to calibrate the relative timing of the signals to each of the memory devices in order to compensate for the timing differences. “Pre-skewing” the timing of signals, for example, by selectively delaying the time at which the respective signals are provided by the memory controller to each of the respective memory devices, can compensate for the timing skew inherent in the memory system. Additionally, periodically performing calibration can be used to compensate for timing drift. A specific proposal for write data strobe to clock calibration for the ranks of memory devices of a memory system has been proposed. In performing the “write levelization,” a memory controller provides the clock signal and a write strobe to each of the memory devices of a rank. The memory devices are each equipped with a SR-latch having the clock signal applied to a set-input and clocked by the respective write strobe signal. The output signal of the SR-latch is provided back to the memory controller as a data signal, which is then used by the memory controller to adjust a time delay for when the write strobe is provided to the rank of memory devices. In this manner, the delay can be adjusted until the write strobe and the clock signal are aligned, as received by the respective memory devices of a rank of memory. In practicing the write levelization process with conventional memory devices, a problem results for memory systems having more than one rank of memory devices. As previously discussed, the preferred operating condition for performing a write operation to a rank of memory devices is to disable the ODT for the rank of memory devices being accessed and enable the ODT for the rank of memory devices not being accessed. Typically, an inactive ODT control signal is provided to the rank of memory devices being accessed to disable the ODT for the data strobe, data, and data mask buffers, and an active ODT control signal is provided to the rank of memory devices not being accessed to enable the ODT for the data strobe, data, and data mask buffers. As previously discussed, the write levelization process requires, however, that a write strobe signal is provided to the memory device to clock a SR-latch, and the output of the SR-latch is provided back to the memory controller, preferably, as a data signal. To accurately simulate write operating conditions, and consequently obtain accurate write levelization, the ODT for the data strobe buffer of the rank of memory devices not being accessed should be enabled, while the ODT for the data buffer for the same rank of memory devices should be disabled to provide the SR-latch output signal back to the memory controller. This preferred condition cannot be set using conventional memory devices having ODT because although the ODT for a memory device can be enabled and disabled using the ODT control signal, the ODT for the data strobe, data, and data mask buffers are enabled and disabled together. Thus, the ODT for the data strobe buffers cannot be enabled while the ODT for the data buffers are disabled, and vice-versa. | <SOH> SUMMARY OF THE INVENTION <EOH>One aspect of the present invention provides an input/output (I/O) buffer that includes on-die terminations (ODTs) that can be enabled and disabled for a first set buffer circuits independently from the ODTs for a second set of the buffer circuits. Another aspect of the invention provides that the ODTs for the buffer circuits of an I/O buffer can be enabled and disabled in response to an ODT control signal, and additionally, the ODTs for a first set of the buffer circuits can be enabled and disabled responsive to the ODT control signal while the ODT for at least one of a second set of the buffer circuits is disabled. In another aspect of the invention, the ODT for at least one data buffer circuit can be disabled while the ODT for a data strobe buffer circuit can be enabled and disabled responsive to a control signal. | 20050120 | 20061121 | 20060720 | 66904.0 | H03K19003 | 7 | LE, DON P | APPARATUS AND METHOD FOR INDEPENDENT CONTROL OF ON-DIE TERMINATION FOR OUPUT BUFFERS OF A MEMORY DEVICE | UNDISCOUNTED | 0 | ACCEPTED | H03K | 2,005 |
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11,040,593 | ACCEPTED | Semiconductor device having conducting portion of upper and lower conductive layers, and method of fabricating the same | A semiconductor device includes a base plate, at least one first conductive layer carried by the base plate, and a semiconductor constructing body formed on or above the base plate, and having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate. An insulating layer is formed on the base plate around the semiconductor constructing body. A plurality of second conductive layers are formed on the insulating layer and electrically connected to the external connecting electrodes of the semiconductor constructing body. A vertical conducting portion is formed on side surfaces of the insulating film and base plate, and electrically connects the first conductive layer and at least one of the second conductive layers. | 1. A semiconductor device comprising: a base plate; at least one first conductive layer carried by the base plate; a semiconductor constructing body formed on or above the base plate, and having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate; an insulating layer formed on the base plate around the semiconductor constructing body; a plurality of second conductive layers formed on the insulating layer and electrically connected to the external connecting electrodes of the semiconductor constructing body; and a vertical conducting portion which is formed on side surfaces of the insulating film and base plate, and electrically connects the first conductive layer and at least one of the second conductive layers. 2. A device according to claim 1, wherein the vertical conducting portion has a groove formed in the side surfaces of the insulating film and base plate, and a vertical conducting layer formed in the groove. 3. A device according to claim 2, wherein an inner surface of the groove continues to the side surfaces of the insulating film and base plate. 4. A device according to claim 2, wherein an inner surface of the groove has a semi-circular planar shape. 5. A device according to claim 1, wherein a ground layer is formed on an upper surface of the base plate and electrically connected to the vertical conducting portion. 6. A device according to claim 5, wherein the semiconductor substrate of the semiconductor constructing body is adhered to the ground layer by a conductive adhesive layer. 7. A device according to claim 1, wherein each of the second conductive layers has a plurality of stacked layers electrically insulated from each other, at least one of uppermost second conductive layers of said plurality of stacked layers has a connecting pad portion, and the uppermost second conductive layers are covered with an upper overcoat film except for the connecting pad portion. 8. A device according to claim 7, wherein a solder ball is formed on the connecting pad portion of the uppermost layer. 9. A device according to claim 1, wherein a ground layer is formed on a lower surface of the base plate and electrically connected to the vertical conducting portion. 10. A device according to claim 1, wherein said at least one first conductive layer is formed on a lower surface of the base plate, and a portion of the first conductive layer is electrically connected to the vertical conducting portion. 11. A device according to claim 10, wherein the first conductive layer comprises a plurality of first conductive layer sections, at least one of lowermost conductive layer sections has a connecting pad portion, and the lowermost first conductive layer sections are covered with a lower overcoat film except for the connecting pad portion. 12. A device according to claim 11, wherein an electronic part is formed on a lower surface of the lower overcoat film and electrically connected to the connecting pad portion of the lowermost first conductive layer section. 13. A semiconductor device fabrication method comprising: arranging, on one side of a base plate carrying at least one first conductive layer, a plurality of semiconductor constructing bodies each having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate, such that said plurality of semiconductor constructing bodies are spaced apart from each other; forming an insulating layer on said one side of the base plate around each semiconductor constructing body; forming a plurality of second conductive layers each having at least one layer on the semiconductor constructing body and insulating layer, such that said plurality of second conductive layers are electrically connected to the external connecting terminals of the semiconductor constructing body; defining a cut line on the insulating layer of the base plate, the cut line defining a region such that at least one semiconductor constructing body is included in the region; forming a vertical conducting portion which includes the cut line to extend to the cut line, and electrically connects the first conductive layer and at least one of the second conductive layers; and cutting the insulating layer, base plate, and vertical conducting portion along the cut line, thereby obtaining a plurality of semiconductor devices each having a portion of the vertical conducting portion on a side surface. 14. A method according to claim 13, wherein forming the vertical conducting portion comprises forming a through hole which extends through the insulating layer and base plate, and forming a vertical conducting layer in the through hole. 15. A method according to claim 14, wherein forming the through hole comprises irradiating the insulating layer and base plate with a laser beam. 16. A method according to claim 13, wherein arranging the semiconductor constructing bodies on the base plate comprises forming a conductive adhesive layer on the base plate, and adhering the semiconductor substrate of each semiconductor constructing body to the conductive adhesive layer. 17. A semiconductor device fabrication method comprising: arranging, on one side of a base plate carrying a plurality of semiconductor constructing bodies each having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate, such that said plurality of semiconductor constructing bodies are spaced apart from each other; forming an insulating layer on said one side of the base plate around each semiconductor constructing body; forming a plurality of second conductive layers each having at least one layer on the semiconductor constructing body and insulating layer, such that said plurality of second conductive layers are electrically connected to the external connecting electrodes of the semiconductor constructing body; forming at least one first conductive layer on a bottom surface of the base plate; defining a cut line on the insulating layer of the base plate, the cut line defining a region such that at least one semiconductor constructing body is included in the region; forming a vertical conducting portion which includes the cut line to extend to the cut line, and electrically connects the first conductive layer and at least one of the second conductive layers; and cutting the insulating layer, base plate, and vertical conducting portion along the cut line, thereby obtaining a plurality of semiconductor devices each having a portion of the vertical conducting portion on a side surface. 18. A method according to claim 17, wherein forming the vertical conducting portion comprises forming a through hole which extends through the insulating layer and base plate, and forming a vertical conducting layer in the through hole. 19. A method according to claim 18, wherein forming the through hole comprises irradiating the insulating layer and base plate with a laser beam. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2004-018537, filed Jan. 27, 2004, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device technique and, more particularly, to a semiconductor device having a conducting portion of upper and lower conductive layers and a method of fabricating the same. 2. Description of the Related Art The conventional semiconductor device disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-298005 includes solder balls as connecting terminals for external connection outside the size of a silicon substrate. Therefore, this semiconductor device has a structure in which a silicon substrate having a plurality of connecting pads on its upper surface is formed on the upper surface of a base plate, an insulating layer is formed on the upper surface of the base plate around the silicon substrate, an upper insulating film is formed on the upper surfaces of the silicon substrate and insulating layer, upper interconnections are formed on the upper surface of the upper insulating film and electrically connected to the connecting pads of the silicon substrate, portions except for connecting pad portions of the upper interconnections are covered with an overcoat film, and solder balls are formed on the connecting pad portions of the upper interconnections. In this conventional semiconductor device, the upper interconnections are formed only above the silicon substrate and on insulating layer. To effectively use the space, it is also possible to form interconnections on the upper or lower surface of the base plate, and connect a portion of the interconnections to a portion of the upper interconnections via a vertical conducting portion extended in a through hole formed in the insulating layer and base plate. In this structure, however, the insulating layer and base plate are present outside the vertical conducting portion in the through hole formed in the insulating layer and base plate. This unnecessarily increases the size of the semiconductor device. BRIEF SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a semiconductor device which can be downsized even when a vertical conducting portion is formed, and a method of fabricating the same. According to an aspect of the present invention, there is provided a semiconductor device comprising: a base plate; at least one first conductive layer carried by the base plate; a semiconductor constructing body formed on or above the base plate, and having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate; an insulating layer formed on the base plate around the semiconductor constructing body; a plurality of second conductive layers formed on the insulating layer and electrically connected to the external connecting electrodes of the semiconductor constructing body; and a vertical conducting portion which is formed on side surfaces of the insulating film and base plate, and electrically connects the first conductive layer and at least one of the second conductive layers. According to another aspect of the present invention, there is provided a semiconductor device fabrication method comprising: arranging, on one side of a base plate carrying at least one a first conductive layer, a plurality of semiconductor constructing bodies each having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate, such that said plurality of semiconductor constructing bodies are spaced apart from each other; forming an insulating layer on said one side of the base plate around each semiconductor constructing body; forming a plurality of second conductive layers each having at least one layer on the semiconductor constructing body and insulating layer, such that said plurality of second conductive layers are electrically connected to the external connecting terminals of the semiconductor constructing body; defining a cut line on the insulating layer of the base plate, the cut line defining a region such that at least one semiconductor constructing body is included in the region; forming a vertical conducting portion which includes the cut line to extend to the cut line, and electrically connects the first conductive layer and at least one of the second conductive layers; and cutting the insulating layer, base plate, and vertical conducting portion along the cut line, thereby obtaining a plurality of semiconductor devices each having a portion of the vertical conducting portion on a side surface. In this technique, the vertical conducting portion is formed on the side surface of the insulating layer formed on the base plate around the semiconductor constructing body, and on the side surface of the base plate. Therefore, neither the insulating layer nor the base plate is present outside the vertical conducting portion, so the semiconductor device can be downsized even when the vertical conducting portion is formed. Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. FIG. 1 is a sectional view of a semiconductor device according to the first embodiment of the present invention; FIG. 2 is a bottom view from which a portion of the semiconductor device shown in FIG. 1 is cut away; FIG. 3 is a sectional view of an assembly initially prepared in the fabrication of the semiconductor constructing body shown in FIGS. 1 and 2; FIG. 4 is a sectional view of the assembly in a step following FIG. 3; FIG. 5 is a sectional view of the assembly in a step following FIG. 4; FIG. 6 is a sectional view of the assembly in a step following FIG. 5; FIG. 7 is a sectional view of the assembly in a step following FIG. 6; FIG. 8 is a sectional view of the assembly in a step following FIG. 7; FIG. 9 is a sectional view of the assembly in a step following FIG. 8; FIG. 10 is a sectional view of the assembly in a step following FIG. 9; FIG. 11 is a sectional view of the assembly in a step following FIG. 10; FIG. 12 is a sectional view of the assembly in a step following FIG. 11; FIG. 13 is a sectional view of the assembly in a step following FIG. 12; FIG. 14 is a bottom view of a portion of the assembly in the state shown in FIG. 13; FIG. 15 is a sectional view of the assembly in a step following FIG. 13; FIG. 16 is a sectional view of the assembly in a step following FIG. 15; FIG. 17 is a sectional view of the assembly in a step following FIG. 16; FIG. 18 is a sectional view of the assembly in a step following FIG. 17; FIG. 19 is a bottom view from which a portion of the assembly in the state shown in FIG. 18 is cut away; FIG. 20 is a sectional view of a semiconductor device according to the second embodiment of the present invention; FIG. 21 is a sectional view of a semiconductor device according to the third embodiment of the present invention; FIG. 22 is a sectional view of an assembly in a predetermined step during the fabrication of the semiconductor device shown in FIG. 21; and FIG. 23 is a sectional view of the assembly in a step following FIG. 22. DETAILED DESCRIPTION OF THE INVENTION First Embodiment FIG. 1 is a sectional view of a semiconductor device according to the first embodiment of the present invention. This semiconductor device includes a base plate 1 having a square planar shape and made of, e.g., a glass fabric base epoxy resin. A ground layer (first conductive layer) 2 having a solid pattern and made of a copper foil is formed on the entire upper surface of the base plate 1. A conductive adhesive layer 3 is formed on the entire upper surface of the ground layer 2. The lower surface of a semiconductor constructing body 4 having a square planar shape and a size smaller to a certain degree than the size of the base plate 1 is adhered to a predetermined portion on the upper surface of the conductive adhesive layer 3. The semiconductor constructing body 4 has interconnections 12, columnar electrodes 13, and a sealing film 14 (all of which will be explained later), and is generally called a CSP (Chip Size Package). Since the individual semiconductor constructing bodies 4 are obtained by dicing after the interconnections 12, columnar electrodes 13, and sealing film 14 are formed on a silicon wafer as will be described later, the semiconductor constructing body 4 is also particularly called a wafer level CSP (W-CSP). The structure of the semiconductor constructing body 4 will be explained below. The semiconductor constructing body 4 includes a silicon substrate (semiconductor substrate) 5 having a square planar shape. The lower surface of the silicon substrate 5 is adhered to the ground layer 2 via the conductive adhesive layer 3. An integrated circuit (not shown) having a predetermined function is formed on the upper surface of the silicon substrate 5. A plurality of connecting pads 6 made of, e.g., an aluminum-based metal are formed on the periphery of the upper surface and electrically connected to the integrated circuit. An insulating film 7 made of silicon oxide or the like is formed on the upper surface of the silicon substrate 5 except for central portions of the connecting pads 6. These central portions of the connecting pads 6 are exposed through holes 8 formed in the insulating film 7. A protective film 9 made of, e.g., an epoxy-based resin or polyimide-based resin is formed on the upper surface of the insulating film 7. Holes 10 are formed in those portions of the protective film 9, which correspond to the holes 8 in the insulating film 7. A plurality of metal undercoatings 11 made of copper or the like are formed on the upper surface of the protective film 9. The interconnections 12 made of copper are respectively formed on the entire upper surface of the metal undercoatings 11. One end portion of each the metal undercoating 11 is electrically connected to the connecting pad 6 through the holes 8 and 10. The columnar electrodes (external connecting electrodes) 13 made of copper are respectively formed on the upper surfaces of connecting pad portions of the interconnections 12. The sealing film 14 made of, e.g., an epoxy-based resin or polyimide-based resin is formed on the upper surface of the protective film 9 and the interconnections 12, such that the upper surface of the sealing film 14 is leveled with the upper surfaces of the columnar electrodes 13. As described above, the semiconductor constructing body 4 called a W-CSP includes the silicon substrate 5, connecting pads 6, and insulating film 7, and also includes the protective film 9, interconnections 12, columnar electrodes 13, and sealing film 14. A square frame-like insulating layer 15 is formed on the upper surface of the base plate 1 around the semiconductor constructing body 4, such that the upper surface of the insulating layer 15 is substantially leveled with the upper surface of the semiconductor constructing body 4. The insulating layer 15 is made of a thermosetting resin such as an epoxy-based resin or polyimide-based resin, or a material obtained by mixing, in a thermosetting resin like this, a reinforcing material such as glass fibers or a silica filler. On the upper surfaces of the semiconductor constructing body 4 and insulating layer 15, an upper insulating film 16 is formed to have a flat upper surface. The upper insulating film 16 is usually called a buildup material used as a buildup substrate, and formed by, e.g., mixing a reinforcing material such as a silica filler in a thermosetting resin such as an epoxy-based resin. Holes 17 are formed in those portions of the upper insulating film 16, which correspond to the central portions of the upper surfaces of the columnar electrodes 13. Upper metal undercoatings 18 made of copper or the like are formed on the upper surface of the upper insulating film 16. Upper interconnections (second conductive layers) 19 made of copper are respectively formed on the entire upper surfaces of the upper metal undercoatings 18. One end portion of each metal undercoating 18 is electrically connected to the upper surface of the columnar electrode 13 through the hole 17 in the upper insulating film 16. An upper overcoat film 20 made of a solder resist or the like is formed on the upper surface of the upper insulating film 16 and the upper interconnections 19. Holes 21 are formed in those portions of the upper overcoat film 20, which correspond to the connecting pad portions of the upper interconnections 19. Solder balls 22 are formed in and above the holes 21 and electrically and mechanically connected to the connecting pad portions of the upper interconnections 19. The solder balls 22 are preferably arranged in a matrix on the upper overcoat film 20. A lower metal undercoating 23 having a solid pattern and made of copper or the like is formed on the entire lower surface of the base plate 1. A lower interconnection (first conductive layer) 24 made of copper is formed on the entire lower surface of the lower metal undercoating 23. The lower interconnection 24 is a solid pattern formed on the entire lower surface of the lower metal undercoating 23, and forms a lower ground layer. A lower overcoat film 25 made of a solder resist or the like is formed on the entire lower surface of the lower interconnection 24. FIG. 2 is a bottom view from which a portion of the semiconductor device shown in FIG. 1 is cut away. Grooves 26 having a substantially semi-circular planar shape are formed in a plurality of predetermined portions, two portions in FIG. 2, of the side surfaces of the base plate 1, ground layer 2, conductive adhesive layer 3, insulating layer 15, and upper insulating film 16. A vertical conducting layer constructed by a metal undercoating 27a made of copper or the like, and a copper layer 27b is formed in each groove 26. That is, a vertical conducting portion 27 is formed by the groove 26, and the vertical conducting layer made up of the metal undercoating 27a and copper layer 27b. A side-surface insulating film 28 made of a solder resist or the like is formed in the groove 26 and thus the copper layer 27b of each vertical conducting portion 27. The vertical conducting portions 27 are in direct contact with and electrically connected to the ground layer 3, portions of the upper interconnections 19 including the upper metal undercoating 18, and the lower interconnection 24 including the lower metal undercoating 23. That is, the ground layer 3 and the lower interconnection 24 forming the lower ground layer are electrically connected to the solder balls 22 for grounding and to the columnar electrodes 13 for grounding of the semiconductor constructing body 4 via the vertical conducting portions 27 and portions of the upper interconnections 19. In this semiconductor device as described above, the grooves 26 having a substantially semi-circular shape in a plane (horizontal section) are formed in the side surfaces of the base plate 1, insulating layer 15, and upper insulating film 16, and the vertical conducting portions 27 for electrically connecting the ground layer 2 and portions of the upper interconnections 19 are formed in the grooves 26. When compared to a structure in which, for example, vertical conducting portions are formed in through holes formed in the base plate 1, insulating layer 15, upper insulating film 16, and the like, none of the base plate 1, insulating layer 15, upper insulating film 16, and the like is present outside the vertical conducting portions 27, so the semiconductor device can be downsized accordingly. The size of the base plate 1 is made larger to some extent than that of the semiconductor constructing body 4, in order to make the size of the formation region of the solder balls 22 larger to a certain degree than that of the semiconductor constructing body 4 in accordance with the increase in number of the connecting pads 6 on the silicon substrate 5, thereby making the size and pitch of the connecting pad portions (the portions in the holes 21 of the upper overcoat film 20) of the upper interconnections 19 larger than those of the columnar electrodes 13. Accordingly, those connecting pad portions of the upper interconnections 19, which are arranged in a matrix are formed not only in a region corresponding to the semiconductor constructing body 4, but also in a region corresponding to the insulating layer 15 formed outside the side surfaces of the semiconductor constructing body 4. That is, of the solder balls 22 which are arranged in a matrix, at least outermost solder balls 22 are formed in a periphery positioned outside the semiconductor constructing body 4. An example of a method of fabricating this semiconductor device will be described below. First, an example of the fabrication method of the semiconductor constructing body 4 will be explained. In this method, an assembly as shown in FIG. 3 is first prepared. In this assembly, connecting pads 6 made of, e.g., an aluminum-based metal, an insulating film 7 made of, e.g., silicon oxide, and a protective film 9 made of, e.g., an epoxy-based resin or polyimide-based resin are formed on an upper side of a wafer-like silicon substrate (semiconductor substrate) 5. Central portions of the connecting pads 6 are exposed through holes 8 and 10 respectively formed in the insulating film 7 and protective film 9. In the wafer-like silicon substrate 5 having this structure, an integrated circuit having a predetermined function is formed in a region where each semiconductor constructing body is to be formed, and each connecting pad 6 is electrically connected to the integrated circuit formed in the corresponding region. Then, as shown in FIG. 4, a metal undercoating 11 is formed on the entire upper surface of the protective film 9 and the upper surfaces of the connecting pads 6 exposed through the holes 8 and 10. The metal undercoating 11 can be any of a copper layer formed by electroless plating, a copper layer formed by sputtering, and a combination of a thin film of titanium or the like formed by sputtering and a copper layer formed on this thin film by sputtering. A plating resist film 31 is formed by patterning on the upper surface of the metal undercoating 11. In this case, holes 32 are formed in those portions of the plating resist film 31, which correspond to regions where interconnections 12 are to be formed. Electroplating of copper is then performed by using the metal undercoating 11 as a plating current path, thereby forming interconnections 12 on the upper surface of the metal undercoating 11 in the holes 32 of the plating resist film 31. After that, the plating resist film 31 is removed. As shown in FIG. 5, a plating resist film 33 is formed by patterning on the upper surface of the metal undercoating 11 including the interconnections 12. In this case, holes 34 are formed in those portions of the plating resist film 33, which correspond to regions where columnar electrodes 13 are to be formed. Electroplating of copper is then performed by using the metal undercoating 11 as a plating current path, thereby forming columnar electrodes 13 on the upper surfaces of connecting pad portions of the interconnections 12 in the holes 34 of the plating resist film 33. After that, the plating resist film 33 is removed, and unnecessary portions of the metal undercoating 11 are etched away by using the interconnections 12 as masks. Consequently, as shown in FIG. 6, the metal undercoating 11 remains only below the interconnections 12. As shown in FIG. 7, a sealing film 14 made of, e.g., an epoxy-based resin or polyimide-based resin is formed on the entire upper surfaces of the protective film 9, the columnar electrodes 13 and interconnections 12 by, e.g., screen printing, spin coating, or die coating, such that the thickness of the sealing film 14 is larger than the height of the columnar electrodes 13. In this state, therefore, the upper surfaces of the columnar electrodes 13 are covered with the sealing film 14. As shown in FIG. 8, the sealing film 14 and the upper surfaces of the columnar electrodes 13 are properly polished to expose the upper surfaces of the columnar electrodes 13, and planarize the upper surface of the sealing film 14 including those exposed upper surfaces of the columnar electrodes 13. The upper surfaces of the columnar electrodes 13 are thus properly polished in order to make the heights of the columnar electrodes 13 uniform by eliminating variations in height of the columnar electrodes 13 formed by electroplating. Then, the lower surface of the silicon substrate 5 is adhered to a dicing tape (not shown), and removed from the dicing tape after a dicing step shown in FIG. 9 is performed. Consequently, a plurality of semiconductor constructing bodies 4, one of which is shown in FIG. 1 are obtained. An example of a method of fabricating the semiconductor device shown in FIG. 1 by using the semiconductor constructing body 4 thus obtained will be described below. First, a base plate 1 as shown in FIG. 10 is prepared. The base plate 1 has a size capable of forming a plurality of base plates 1, one of which is shown in FIG. 1, and has a square planar shape, although the shape is not particularly limited. In this case, a ground layer 2 having a solid pattern and made of a copper foil is formed on the entire upper surface of the base plate 1, and a conductive adhesive layer 3 is formed on the entire upper surface of the ground layer 2. Referring to FIG. 10, regions indicated by reference numeral 41 correspond to dicing lines (cut lines). As shown in FIG. 11, the lower surfaces of the silicon substrates 5 of the semiconductor constructing bodies 4 are adhered to a plurality of predetermined portions on the upper surface of the conductive adhesive layer 3. Since the individual semiconductor constructing bodies 4 are obtained by cutting the base plate 1 from the dicing lines 41, each semiconductor constructing body 4 is fixed to a position where the cut position of the semiconductor constructing body 4 is aligned with the dicing line 41. Then, an insulating layer formation layer 15a is formed on the upper surface of the conductive adhesive layer 3 around the semiconductor constructing body 4 by, e.g., screen printing or spin coating. The insulating layer formation layer 15a is made of, e.g., a thermosetting resin such as an epoxy-based resin or polyimide-based resin, or a material obtained by mixing, in a thermosetting resin like this, a reinforcing material such as a silica filler. Subsequently, an upper insulating film formation sheet 16a is placed on the upper surfaces of the semiconductor constructing bodies 4 and insulating layer formation layer 15a. The upper insulating film formation sheet 16a is preferably made of a sheet-like buildup material, although the material is not particularly limited. For example, this buildup material is obtained by mixing a silica filler in a thermosetting resin such as an epoxy-based resin, and semi-curing the thermosetting resin. Note that it is also possible to use, as the upper insulating film formation sheet 16a, a prepreg material obtained by impregnating glass fibers with a thermosetting resin such as an epoxy-based resin, and semi-curing the thermosetting resin into the form of a sheet, or a sheet made only of a thermosetting resin in which no silica filler is mixed. As shown in FIG. 12, a pair of heating/pressing plates 42 and 43 are used to heat and press, from above and below, the insulating layer formation layer 15a and upper insulating film formation sheet 16a. Consequently, an insulating layer 15 is formed on the upper surface of the conductive adhesive layer 3 around the semiconductor constructing body 4, and an upper insulating film 16 is formed on the upper surfaces of the semiconductor constructing bodies 4 and insulating layer 15. In this case, the upper surface of the upper insulating film 16 is a flat surface because it is pressed by the lower surface of the upper heating/pressing plate 42. Accordingly, no polishing step of planarizing the upper surface of the upper insulting film 16 is necessary. As shown in FIG. 13, after removing of the plates 42, 43, laser processing which applies a laser beam is used to form holes 17 in those portions of the upper insulating film 16, which correspond to the central portions of the upper surfaces of the columnar electrodes 13. Also, as shown in FIG. 14 which is a bottom view of a portion in the state shown in FIG. 13, a mechanical drill is used to form through holes 26a in regions corresponding to parts of the dicing lines 41 and their two sides. Each through hole 26a is vertically penetrates predetermined portions of the upper insulating film 16, insulating layer 15, conductive adhesive layer 3, ground layer 2, and base plate 1, and has a circular horizontal sectional shape whose diameter is larger to some extent than the width of the dicing line 41. That is, the through hole 26a extends to those regions of the base plate 1 and insulating layer 15, which include the dicing line 41 and its two side portions. Then, if necessary, epoxy smear and the like occurring in the holes 17 and the like are removed by a desmear process. As shown in FIG. 15, an upper metal undercoating 18, lower metal undercoating 23, and metal undercoating 27a are formed by electroless plating or sputtering of copper on the entire upper surface of the upper insulating film 16 including the upper surfaces of the columnar electrodes 13 exposed through the holes 17, on the entire lower surface of the base plate 1, and on the inner surfaces of the through holes 26a. A plating resist film 44 is then formed by patterning on the upper surface of the upper metal undercoating 18. In this case, holes 45 are formed in those portions of the plating resist film 44, which correspond to formation regions of upper interconnections 19. Electroplating of copper is then performed by using the upper metal undercoatings 18, 23, and 27a as plating current paths, thereby forming upper interconnections 19 on the upper surface of the upper metal undercoating 18 in the holes 45 of the plating resist film 44. Also, a lower interconnection 24 is formed on the lower surface of the lower metal undercoating 23, and a copper layer 27b is formed on the surface of the metal undercoating 27a in each through hole 26a. After that, the plating resist film 44 is removed, and unnecessary portions of the upper metal undercoating 18 are etched away by using the upper interconnections 19 as masks. Consequently, as shown in FIG. 16, the upper metal undercoating 18 remains only below the upper interconnections 19. In this state, a cylindrical vertical conducting portion 27 having the metal undercoating 27a and copper layer 27b is formed in each through hole 26a. As shown in FIG. 17, an upper overcoat film 20 made of, e.g., a solder resist is formed on the upper surfaces of the upper insulating film 16 and the upper interconnections 19 by, e.g., screen printing. In this case, holes 21 are formed in those portions of the upper overcoat film 20, which correspond to connecting pad portions of the upper interconnections 19. Also, a lower overcoat film 25 made of, e.g., a solder resist is formed on the entire lower surface of the lower interconnection 24. In addition, a side-surface insulating film 28 made of, e.g., a solder resist is formed in each vertical conducting portion 27. Then, solder balls 22 which are electrically connected to the connecting pad portions of the upper interconnections 19, are formed in and above the holes 21. After that, as shown in FIGS. 18 and 19, the upper overcoat film 20, upper insulating film 16, insulating layer 15, conductive adhesive layer 3, ground layer 2, base plate 1, lower overcoat film 25, vertically extended conducting portions 27, and side-surface insulating film 28 are vertically cut, along the dicing lines 41, in substantially the centers of the surface shapes of the through holes 17 between the semiconductor constructing bodies 4, thereby obtaining a plurality of semiconductor devices one of which is shown in FIG. 1. In this case, the inner wall surfaces of the grooves 26 of the vertical conducting portions 27 continue to the side surfaces of the base plate 1 and insulating film 15 to form the side surfaces around each semiconductor device. In the fabrication method described above, a plurality of semiconductor constituent bodies 4 are initially arranged on the base plate 1, and the upper interconnections 19, lower interconnection 24, vertical conducting portions 27, and solder balls 22 are collectively formed for the semiconductor constructing bodies 4. After that, the resultant structure is cut to obtain a plurality of semiconductor devices. Accordingly, the fabrication steps can be simplified. Also, from the fabrication step shown in FIG. 12, a plurality of semiconductor constructing bodies 4 can be transferred together with the base plate 1. This also simplifies the fabrication steps. Second Embodiment FIG. 20 is a sectional view of a semiconductor device according to the second embodiment of the present invention. This semiconductor device differs from that shown in FIG. 1 in that lower interconnections 24 each including a lower metal undercoating 23 are regular interconnections obtained by patterning, holes 51 are formed in those portions of a lower overcoat film 25, which correspond to connecting pad portions of the lower interconnections 24, and a chip part 52 which is, e.g., a capacitor or resistor is mounted on the connecting pad portions of the lower interconnections 24 via conductive materials 53 made of solder or the like. In this case, the lower interconnections 24 are regular interconnections, so the number of vertical conducting portions 27 for connecting at least portions of the lower interconnections 24 and at least portions of upper interconnections 19 are set in accordance with the number of the lower interconnections 24. Third Embodiment FIG. 21 is a sectional view of a semiconductor device according to the third embodiment of the present invention. A difference from the semiconductor device shown in FIG. 20 is that this semiconductor device has neither a ground layer 2 nor a conductive adhesive layer 3, and the lower surface of a silicon substrate 5 of a semiconductor constructing body 4 is adhered to the upper surface of a base plate 1 via an adhesive layer 54 made of a die bonding material. Part of an example of a method of fabricating this semiconductor constructing body will be described below. After the step shown in FIG. 8, as shown in FIG. 21, the adhesive layer 54 is adhered to the entire lower surface of the silicon substrate 5. The adhesive layer 54 is made of a die bonding material such as an epoxy-based resin or polyimide-based resin, and fixed, in a semi-cured state, to the silicon substrate 5 by heating and pressing. Then, the adhesive layer 54 fixed to the silicon substrate 5 is adhered to a dicing tape (not shown), and removed from the dicing tape after a dicing step shown in FIG. 22 is performed. Consequently, a plurality of semiconductor constructing bodies 4 each having the adhesive layer 54 on the lower surface of the silicon substrate 5 are obtained, as shown in FIG. 23. The semiconductor constructing body 4 thus obtained has the adhesive layer 54 on the lower surface of the silicon substrate 5. This obviates the need for a very cumbersome operation of forming an adhesive layer on the lower surface of the silicon substrate 5 of each semiconductor constructing body 4 after the dicing step. The operation of removing an adhesive layer from the dicing tape after the dicing step is much easier than the operation of forming an adhesive layer on the lower surface of the silicon substrate 5 of each semiconductor constructing body 5 after the dicing step. To fix the semiconductor constructing body 4 on the base plate 1, the adhesive layer 54 need only be finally cured by heating and pressing. Other Embodiments In the above embodiments, the through hole 26a of each vertical conducting portion 27 has a circular planar shape formed by laser processing, and the wafer is cut along a cut line which runs trough substantially the center of each circle. However, the planar shape of the through hole 26a is not limited to a circle, but may also be a rectangle, rhombus, or scalene polygon. Also, although the conductive layer is formed by plating on the inner surface of the through hole 26a, conductive paste may also be filled. Furthermore, in, e.g., FIG. 20, each of the upper interconnections 19 formed on the upper insulating film 16 through the metal layers 18 is made up of a single layer, and each of the lower interconnections 24 formed below the lower insulating film or base through the metal layers 23 is also made of a single layer. However, both upper and lower interconnections 19, 24 may also be made up of two or more laminated layers. Also, an electronic part 53 mounted below the lower overcoat film 25 need not be the chip part. For example, it is also possible to mount a bare chip or CSP. In addition, in the above embodiments, the semiconductor constructing body 4 has the columnar electrodes 13 as external connecting electrodes. However, the semiconductor constructing body 4 may also have interconnections 12 having connecting pad portions as external connecting electrodes, instead of the columnar electrodes, or may also have connecting pads 6 as external connecting electrodes, instead of the columnar electrodes and interconnections. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a semiconductor device technique and, more particularly, to a semiconductor device having a conducting portion of upper and lower conductive layers and a method of fabricating the same. 2. Description of the Related Art The conventional semiconductor device disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-298005 includes solder balls as connecting terminals for external connection outside the size of a silicon substrate. Therefore, this semiconductor device has a structure in which a silicon substrate having a plurality of connecting pads on its upper surface is formed on the upper surface of a base plate, an insulating layer is formed on the upper surface of the base plate around the silicon substrate, an upper insulating film is formed on the upper surfaces of the silicon substrate and insulating layer, upper interconnections are formed on the upper surface of the upper insulating film and electrically connected to the connecting pads of the silicon substrate, portions except for connecting pad portions of the upper interconnections are covered with an overcoat film, and solder balls are formed on the connecting pad portions of the upper interconnections. In this conventional semiconductor device, the upper interconnections are formed only above the silicon substrate and on insulating layer. To effectively use the space, it is also possible to form interconnections on the upper or lower surface of the base plate, and connect a portion of the interconnections to a portion of the upper interconnections via a vertical conducting portion extended in a through hole formed in the insulating layer and base plate. In this structure, however, the insulating layer and base plate are present outside the vertical conducting portion in the through hole formed in the insulating layer and base plate. This unnecessarily increases the size of the semiconductor device. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>It is, therefore, an object of the present invention to provide a semiconductor device which can be downsized even when a vertical conducting portion is formed, and a method of fabricating the same. According to an aspect of the present invention, there is provided a semiconductor device comprising: a base plate; at least one first conductive layer carried by the base plate; a semiconductor constructing body formed on or above the base plate, and having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate; an insulating layer formed on the base plate around the semiconductor constructing body; a plurality of second conductive layers formed on the insulating layer and electrically connected to the external connecting electrodes of the semiconductor constructing body; and a vertical conducting portion which is formed on side surfaces of the insulating film and base plate, and electrically connects the first conductive layer and at least one of the second conductive layers. According to another aspect of the present invention, there is provided a semiconductor device fabrication method comprising: arranging, on one side of a base plate carrying at least one a first conductive layer, a plurality of semiconductor constructing bodies each having a semiconductor substrate and a plurality of external connecting electrodes formed on the semiconductor substrate, such that said plurality of semiconductor constructing bodies are spaced apart from each other; forming an insulating layer on said one side of the base plate around each semiconductor constructing body; forming a plurality of second conductive layers each having at least one layer on the semiconductor constructing body and insulating layer, such that said plurality of second conductive layers are electrically connected to the external connecting terminals of the semiconductor constructing body; defining a cut line on the insulating layer of the base plate, the cut line defining a region such that at least one semiconductor constructing body is included in the region; forming a vertical conducting portion which includes the cut line to extend to the cut line, and electrically connects the first conductive layer and at least one of the second conductive layers; and cutting the insulating layer, base plate, and vertical conducting portion along the cut line, thereby obtaining a plurality of semiconductor devices each having a portion of the vertical conducting portion on a side surface. In this technique, the vertical conducting portion is formed on the side surface of the insulating layer formed on the base plate around the semiconductor constructing body, and on the side surface of the base plate. Therefore, neither the insulating layer nor the base plate is present outside the vertical conducting portion, so the semiconductor device can be downsized even when the vertical conducting portion is formed. Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. | 20050121 | 20080401 | 20050728 | 71385.0 | 0 | WILLIAMS, ALEXANDER O | SEMICONDUCTOR DEVICE HAVING CONDUCTING PORTION OF UPPER AND LOWER CONDUCTIVE LAYERS | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,040,619 | ACCEPTED | Read-write processing apparatus and method for RFID tag | A read-write processing apparatus communicates with an RFID tag provided with a semiconductor memory to exchange commands and responses through antenna coils. A condition under which only a carrier wave is transmitted is set prior to a communication with the RFID tag and a level from a reception signal obtained under this condition is extracted as noise level. The extracted noise level is displayed or outputted to an output host apparatus. | 1. An apparatus for communicating with an RFID tag provided with a semiconductor memory to read and write data from and into said semiconductor memory, said apparatus comprising: wait condition setting means for setting a wait condition prior to a communication with said RFID tag, only a carrier wave being transmitted under said wait condition; noise level extracting means for extracting as noise level a level from a reception signal obtained under said wait condition; and reporting means for displaying or outputting said extracted noise level. 2. The apparatus of claim 1 further comprising: history data memory that stores history data on processes of each time; and storing means for storing said extracted noise level in said history data memory in correlation with data that indicate success and failure of communication with said RFID tag. 3. An apparatus for communicating with an RFID tag provided with a semiconductor memory to read and write data from and into said semiconductor memory, said apparatus comprising: signal extracting means for extracting level of a data signal and level of a base signal from a signal being received in a communication process with said RFID tag, said data signal and said base signal respectively corresponding to a period during which said RFID tag switches and does not switch impedance periodically; calculating means for calculating the ratio or the difference between the levels of said data signal and said base signal; and reporting means for displaying or outputting result of calculation by said calculating means. 4. The apparatus of claim 3 further comprising communication control means for comparing a numerical value obtained by said calculating means with a specified threshold value and stopping said communication process when said numerical value changes so as to cross said threshold value. 5. The apparatus of claim 3 further comprising: history data memory that stores history data on processes of each time; and storing means for storing the result of calculation by said calculating means in said history data memory in correlation with data that indicate success and failure of communication with said RFID tag. 6. The apparatus of claim 4 further comprising: history data memory that stores history data on processes of each time; and storing means for storing the result of calculation by said calculating means in said history data memory in correlation with data that indicate success and failure of communication with said RFID tag. 7. An apparatus for communicating with an RFID tag provided with a semiconductor memory to read and write data from and into said semiconductor memory, said apparatus comprising: wait condition setting means for setting a wait condition prior to a communication with said RFID tag, only a carrier wave being transmitted under said wait condition; noise level extracting means for extracting as noise level a level from a reception signal obtained under said wait condition; and communication control means for discontinuing said wait condition and starting a communication with said RFID tag after a condition in which said noise level remains smaller than a specified value has continued for a specified length of time. 8. A method of communicating with an RFID tag provided with a semiconductor memory to read and write data from and into said semiconductor memory, said method comprising the steps of: setting a wait condition prior to a communication with said RFID tag, only a carrier wave being transmitted under said wait condition; extracting as noise level a level from a reception signal obtained under said wait condition; and displaying or outputting said extracted noise level. 9. A method of communicating with an RFID tag provided with a semiconductor memory to read and write data from and into said semiconductor memory, said method comprising the steps of: extracting level of a data signal and level of a base signal from a signal being received in a communication process with said RFID tag, said data signal and said base signal respectively corresponding to a period during which said RFID tag switches and does not switch impedance periodically; calculating the ratio or the difference between the levels of said data signal and said base signal; and displaying or outputting result of calculation by said calculating means. | Priority is claimed on Japanese Patent Applications 2004-018255 filed Jan. 27, 2004 and 2005-004702 filed Jan. 12, 2005. BACKGROUND OF THE INVENTION This invention relates to a read-write processing apparatus for carrying out non-contact communications with an RFID tag containing a semiconductor memory to read out or write data from or into this memory and a read-write method that is carried out by such an apparatus. Systems having a memory medium storing various data attached to each article to be transported and being adapted to read and write data from and into this memory medium by wireless communications are coming to be introduced into control sites of cargoes and assembly lines of factories. Such a system is referred to as an RFID (radio frequency identification) system and the aforementioned memory medium to be attached to each article to be transported contains an IC chip containing a semiconductor memory and a communication antenna coil and is commonly referred to as an RFID tag or a non-contact IC tag. Prior art read-write processing apparatus for an RFID system are structured as a reader-writer having both an antenna part and a control unit inside a same housing structure, as a controller separate from an antenna part or as a controller that contains the transmission-reception circuit and the control part of the antenna part. Both when reading and writing data, prior art read-write processing apparatus are adapted to transmit a command of a specified format to an RFID tag and to receive from the RFID tag a response to this command. When an RFID tag without containing an inner power source is used, an induced electromotive force is generated in the antenna coil on the side of the RFID tag by means of transmission waves from the antenna part such that a control circuit inside the RFID tag will be driven. With an RFID system as described above, there is a high probability that various kinds of noise will come to be mixed in the communication region for the tag and the antenna part so as to cause communication errors since the system is often introduced in an environment where machines and apparatus of various types are installed. For this reason, it is necessary to carry out test communications prior to actual system operations and to thereby check whether or not the system is in a condition capable of carrying out communications with RFID tags without any trouble. In view of the above, the present applicant has earlier proposed a read-write processing apparatus provided with a test mode in which a read-write process is carried out and the distance to the tag is adjusted, and a display light is switched on if a communication error occurs. (See Japanese Patent Koho 2,610,897). By the invention of aforementioned Japanese Patent Koho 2,610,897, the user can conclude that the antenna part and the RFID tag are in a condition for communicating to each other if this display light is not lit. When such an RFID system is put in an actual use in a real situation, however, there is a possibility of a communication error due, for example, to a sudden occurrence of noise, say, because of the operations of surrounding machines. It is difficult to predict, however, when and how such sudden noise may occur and the real situation is that no sufficient measure is being taken against noise. In view of this, Japanese Patent Koho 9-190518 discloses a method according to which the read-write processing apparatus transmits to the RFID tag a command to request for the transmission of a pseudo random signal and correlation values are obtained with two kinds of reception signals to this command (signals with data arrangement similar to and not similar to that of the transmission signal from the RFID tag). Only if the correlation value C1 with the signal similar to the transmission signal is greater than a first threshold value T1 and the correlation value C2 with the signal not similar to the transmission signal is less than a second threshold value T2, an access is allowed for reading out data. According to the invention of aforementioned Japanese Patent Koho 9-190518, reliability of communication process can be improved because actual communication can be started only after it is ascertained that the noise level is low. This invention has problems, however, in that the process becomes complicated because special communications must be carried out between the read-write processing apparatus and the RFID tag for checking the status of noise and that the read-write processing apparatus is required to carry out two correlation calculation processes. Under a circumstance where the variations of noise are large, furthermore, although a communication process may be started after it is ascertained that the two correlation values C1 and C2 both satisfy the aforementioned conditions, there may arise a sudden change in the noise and a communication error may result. Moreover, communication errors are not limited to be caused by noise but may be caused also for reasons other than noise such as a fault in the RFID tag. In the situation of a communication error, prior art systems inclusive of those according to aforementioned Japanese Patents Koho 2,610,897 and 9-190518 are not adapted to check whether or not it was caused by noise. SUMMARY OF THE INVENTION It is therefore an object of this invention to make it possible for the user, when a communication error has occurred in a communication process with an RFID tag, to easily ascertain whether this error was due to noise or not. It is another object of the invention to prevent the occurrence of a communication error with a high level of reliability by stopping the communication or preventing the start of a communication under a condition of a high noise level. This invention relates to a read-write processing apparatus for communicating with an RFID tag provided with a semiconductor memory to read and write data from and into this semiconductor memory, preferably equipped with a control part comprising a computer. Such a read-write processing apparatus may be formed as a reader-writer having an antenna part for communicating with the RFID tag (inclusive of an antenna coil as well as a transmitter circuit and a receiver circuit for signals) inside a same housing structure but is not so limited. It may be structured as a controller separate from such an antenna part. It may also be structured as a controller that contains the transmitter and receiver circuits of the antenna part. Since the RFID tag is set so as to operate according to a command from the read-write processing apparatus, reception signals under a condition where no command is being transmitted do not contain any transmission signal from the RFID tag. Thus, the amplitude of variations in the reception signal may be considered to reflect the noise level. A read-write apparatus according to a first embodiment of this invention was conceived in view of the above and comprises wait condition setting means for setting prior to a communication with the RFID tag a wait condition under which only a carrier wave is transmitted, noise level extracting means for extracting as noise level a level from a reception signal obtained under this wait condition, and reporting means for displaying or outputting this extracted noise level. The wait condition setting means can cause the antenna part to transmit only the carrier wave by not outputting any data that form a command. The noise level extracting means includes preferably a level extracting circuit (having a detection circuit and an A/D converter circuit) for processing a reception signal, as well as a signal processing part for processing the output from the level extracting circuit. The level extracting circuit is adapted to extract the level of an envelope line of this reception signal by means of its detection circuit. The signal processing part may be structured so as to take in the output from the level extracting circuit for a plural number of times, to obtain their average and dispersion values and to determine the noise level from the results of its calculations. The wait condition setting means and the signal processing part may be formed by installing a program necessary for their processing into the computer that comprises the aforementioned control part. The level extracting circuit may be provided independently of an ordinary receiver circuit. If the read-write processing apparatus is structured as a controller separate from the antenna part, the level extracting circuit may be contained in the housing structure for the antenna part. In such a case, the level extracting circuit is not contained by the noise level extracting means and the level extracting means may be formed with an input part for taking in the output from the level extracting circuit and the aforementioned signal processing part. If the reporting means is formed as a displaying means, the noise level may be shown as a numerical value but it may also be shown as an analog display such as a bar graph. The noise level may also be displayed in several steps such as levels 1, 2, 3, etc. Such display means may be set on the surface of a housing structure forming the main body of the read-write processing apparatus. If the reporting means is formed as outputting means for outputting the noise level to the outside, it may be formed as an output interface of a personal computer or a programmable logic controller (PLC) to a host apparatus. This output need not be digital signals. This may be outputted as an analog signal. With a structure as described above, a wait period of a specified length can be set before a communication is started as the condition for a start of such a communication with the RFID tag such as the receipt of a command from a host apparatus comes to be satisfied. Thus, the noise level can be extracted during this period and the result of the extracted level can be reported to the user. In the case of a communication error, the user can easily ascertain whether the error is due to noise or not from the noise level that has been reported. According to a preferred embodiment, the read-write processing apparatus of this invention may further comprise history data memory that stores history data on processes of each time and storing means for storing the extracted noise in the history data memory in correlation with data that indicate success and failure of communication with the RFID tag. With an apparatus thus structured, history data correlating the noise level extracted immediately before the communication of each time with a success or a failure of the communication can be stored. Thus, the user can make use of such history data to recognize the noise level when a communication fails and investigate the cause of the failure in the communication. If data indicative of date are correlated in the history data and a host apparatus stores history of operations of apparatus near the read-write processing apparatus and the RFID tag, for example, the source of noise for a communication error under a condition of high noise level can be estimated from the status of the site at the time of the occurrence of the error. If the history of operations of peripheral apparatus is separately accumulated, in particular, causal relationships between the communication process and the peripheral apparatus may also be estimated and an apparatus that was operating at the time of occurrence of the error may be picked as a candidate to the source of error. The response returned by the RFID tag to the read-write processing apparatus includes both a portion where the impedance in the tag is switched at a specified frequency and a portion where the impedance switching does not take place. Data that form a response are an arrangement of “1”s and “0”s in a specified order but data are each expressed as a combination of a part where the impedance is switched and a part where the impedance is not switched. In the reception signal to the response on the side of the read-write processing apparatus, a signal with large changes in the level (hereinafter referred to as the data signal) appears during a period when the impedance is being switched and a signal with small changes in the level (hereinafter referred to as the base signal) appears during a period when the impedance is not being switched. The read-write processing apparatus can separate the data signal and the base signal in the receiving circuit by carrying out a binarization process on the demodulated reception signal but if there is a large level change in the base signal due to noise, the difference between the data signal and the base signal becomes small and a possibility of a communication error arises. A read-write processing apparatus according to a second embodiment of this invention was conceived in view of the above and comprises signal extracting means for extracting level of a data signal (as defined above) and level of a base signal (as defined above) from a signal being received in a communication process with the RFID tag, calculating means for calculating the ratio or the difference between the levels of the data signal and the base signal, and reporting means for displaying or outputting the result of calculation by the calculating means. The signal extracting means in the above, like the noise level extracting means of the read-write processing apparatus according to the first embodiment, may include a level extracting circuit and a signal processing part. The signal processing part is preferably adapted to carry out the extraction of signal level while known data are being transmitted from the RFID tag. As for the known data in the above, it is preferable to use the fixed data positioned at the front part of the response. The fixed data in the above, referred to as the start code, are for the purpose of showing that it is a response from the RFID tag, and generally data of a specified number of bits are arranged in a given sequence. When the signal level of a period during which the start code is being transmitted is extracted, the signal processing part can recognize a period during which a signal corresponding to the start code is being inputted on the basis of an input from the receiver circuit and input the levels of a data signal and a base signal during this period extracted by the level extracting circuit. In this case, the level of the signal extracted from the data signal corresponds to the aforementioned period during which the RFID tag is switching the impedance periodically and the level of the signal extracted from the base signal corresponds to the aforementioned period during which the RFID tag is not switching the impedance periodically. For each of the base signal and the data signal, it is preferable to repeat the sampling for a plural number of times and to determine the signal level on the basis of the average or dispersion value of the sampled values. The calculating means may be set by installing a program necessary for the control but may be structured as an IC chip incorporating a divider circuit or a subtractor circuit. The reporting means may be structured like the reporting means for the first read-write processing apparatus described above. With the second read-write processing apparatus described above, a numerical value representing the ratio or difference between the levels of a data signal and a base signal in a signal being received during a communication with the RFID can be obtained and reported to the user. Thus, when there is a communication error, the user can easily determine whether the error was caused by noise or not on the basis of the reported numerical value. When a report is made to the user, it need not be the numerical value itself that should be displayed but may be analog data such as a bar graph. With the second read-write processing apparatus described above, the level of a signal extracted from a data signal becomes lower as the RFID tag moves farther away from the antenna coil of the read-write processing apparatus but it may be considered that no large change will appear in a signal extracted from a base signal. In other words, it may be thought that the difference in the levels of these two kinds of signals will become smaller as the distance (communication distance) between the antenna coil and the RFID tag becomes greater. Thus, this read-write processing apparatus may be used to check the adequacy of the communication distance from the reported result of the calculation when a test communication is carried out for adjusting the communication distance. It is preferable to further provide the read-write processing apparatus according to the second embodiment of the invention with communication control means for comparing a numerical value obtained by the calculating means with a specified threshold value and stopping the communication process when the numerical value changes so as to cross the threshold value. Thus, the communication control means can stop the communication process on the basis of the calculations by the calculating means if the numerical value obtained by the calculating means changes so as to cross the threshold value either from above to below or from below to above. If the calculating means is adapted to divide the level S extracted from a data signal by the level N extracted from a base signal, for example, the communication process can be stopped when the ratio S/N thus obtained changes from a value greater than the threshold value to a smaller value than the threshold value because the ratio becomes smaller as the value of N increases. This communication control means, too, can be set by installing a program necessary for the control. The communication process can be stopped by this means when a large noise occurs suddenly and hence the occurrence of a communication error due to such noise can be prevented. It is preferable to arrange such that a stopped communication process will be restarted after the elapse of a specified length of time. It is also preferable to further provide the read-write processing apparatus according to the second embodiment of the invention with history data memory that stores history data on processes of each time and storing means for storing the result of calculation by the calculating means in the history data memory in correlation with data that indicate success and failure of communication with the RFID tag. This memory and the storing means may be similar to those described above for introducing to the read-write processing apparatus according to the first embodiment of the invention. Thus, the user can estimate the source of noise that caused a failure in a communication by analyzing these history data. A read-write processing apparatus according to a third embodiment of this invention is characterized as comprising wait condition setting means for setting a wait condition prior to a communication with the RFID tag, only a carrier wave being transmitted under this wait condition, noise level extracting means for extracting as noise level a level from a reception signal obtained under the wait condition, and communication control means for discontinuing the wait condition and starting a communication with the RFID tag after a condition in which the noise level remains smaller than a specified value has continued for a specified length of time. The wait condition setting means and the noise level extracting means in the above may be similar to those comprising the read-write processing apparatus according to the first embodiment of the invention described above. It is preferable in the above, however, to make the wait condition to last not for a fixed length of time but for an adjustable length of time. In particular, it is preferable to make it adjustable such that a clock that measures the time is reset to zero when the noise level becomes greater than the aforementioned specified value and the wait condition lasts until the condition with a low noise level has continued for a specified length of time. In this way, the start of a communication process can be made to wait until a condition with a stable noise level is regained and the occurrence of a communication error can be prevented. The communication control means of this embodiment can also be set by installing a necessary program in the control part as in the case of the read-write processing apparatus according to the second embodiment of the invention. The invention also relates to a method of communicating with an RFID tag provided with a semiconductor memory to read and write data from and into the semiconductor memory. A method according to a first embodiment of this invention comprises the steps of setting a wait condition prior to a communication with the RFID tag, only a carrier wave being transmitted under this wait condition, extracting as noise level a level from a reception signal obtained under the wait condition, and displaying or outputting the extracted noise level. This method may be interpreted as the method carried out by the read-write processing apparatus according to the first embodiment of the invention described above although these steps can be carried out by different devices. For example, the read-write processing apparatus may be used for the first two steps and the third step may be carried out by a personal computer or the like. A method according to a second embodiment of this invention comprises the steps of extracting level of a data signal and level of a base signal from a signal being received in a communication process with the RFID tag, the data signal and the base signal respectively corresponding to a period during which the RFID tag switches and does not switch impedance periodically, calculating the ratio or the difference between the levels of the data signal and the base signal, and displaying or outputting the result of calculation by the calculating means. This method may be interpreted as the method carried out by the read-write processing apparatus according to the second embodiment of the invention described above although these three steps may each be carried out by a different device. For example, the first step may be carried out by the read-write processing apparatus to output the two signal levels to another device such as a personal computer such that the second step and the third step may be carried out by such other device. By this invention, since the user is informed of the noise level when a communication is carried out with the RFID tag, the user can easily ascertain at the time of a communication error whether or not it is caused by noise. Moreover, if the noise level is high after a communication with the tag, the subsequent communication process may be stopped and it may be restarted again after a condition of a low noise level lasts for a specified length of time. Thus, the occurrence of a communication error can be prevented with a high level of reliability and a communication process can be carried out in a stable manner. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the structure of a reader-writer of this invention and a RFID tag with which it carries out communications. FIG. 2 is a timing chart for the signals related to the transmission and reception by the reader-writer. FIG. 3 shows an example of detection process carried out by the level extracting circuit. FIG. 4 is a timing chart for showing the flow of communication processes among the reader-writer, the tag and a host apparatus. FIG. 5 is a flowchart of a control routine for obtaining the noise level before the communication process. FIG. 6 is a drawing for showing an example of signal processing on the start code. FIG. 7 is a flowchart of a control routine for obtaining a signal-to-noise ratio during communication by the processing of FIG. 6. FIG. 8 is a table showing an example of history data that may be stored in the reader-writer. FIG. 9 is a flowchart of a control routine for starting a communication process upon ascertaining that the noise level is low. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 is a block diagram showing the structure of a reader-writer 1 embodying this invention and an RFID tag (hereinafter referred to simply as a tag) 2 as its object of communication. The tag 2 in this example does not contain a power source, being of the type that operates by an induced electromotive force generated by transmitted waves from the reader-writer 1, and is provided with a control part 21 and a semiconductor memory 22. The tag 2 also comprises an antenna coil 23, a capacitor 24 and a load switch 25 (a resistor with a contact point, according to this example) for communication. The control part 21 of this tag 2 includes not only a computer but also peripheral circuits such as a demodulation circuit for demodulating transmitted signals from the reader-writer 1. The reader-writer 1 is formed with a control part 10, an antenna coil 11, a transmitter circuit 12, a receiver circuit 13, an oscillator circuit 14 and a Z conversion circuit 101 for a matching process on the antenna coil 11 placed inside a housing structure (not shown). This housing structure is further provided with a display part 15, an interface (I/F) circuit 16, an input-output (I/O) circuit 17 and a level extracting circuit 18. The control part 10 on the side of the reader-writer 1 is a computer and carries out communication processing with the tag 2 according to a program stored in an internal memory. This control part 10 is also adapted to output high-frequency pulses based on pulse signals from the oscillator circuit 14. The high-frequency pulses become the basis of a carrier wave. When communicating with the tag 2, the control part 10 also serves to output, as a pulse signal, data that represent the content of a command. This output pulse signal is also referred to as a command signal. The transmitter circuit 12, referred to above, includes a driver circuit 102, a modulator circuit 103, a tuning-amplifying circuit 105 and a pair of Z conversion circuits 104 and 106 sandwiching this tuning-amplifying circuit 105. The receiver circuit 13 includes a bandpass filter (BPF) circuit 107, a detection circuit 108, a low pass filter (LPF) circuit 109, an amplifier circuit 110 and a comparator circuit 111. The aforementioned command signal is transmitted from the control part 10 to the modulator circuit 103. The aforementioned display part 15 comprises a numerical displayer and a plurality of display lights (not shown) and may be at an appropriate position on the housing structure. The interface circuit 16 is used for communication with host apparatus (not shown) such as personal computers and PLCs. The input-output circuit 17 is used for taking in external signals and outputting results of processing. The level extracting circuit 18 is for taking out the level of the reception signal as digital data and is formed with a detector circuit 112 and an A/D converter circuit 113. FIG. 2 is a timing chart for the signals related to the transmission and reception by the reader-writer 1 described above. FIG. 2(1) shows the signals related to the command transmission to the tag 2 and FIG. 2(2) shows the signals related to the reception of a response. In FIG. 2(1), (a) shows the aforementioned carrier wave. In the illustrated example, its frequency is set as 13.56 MHz. In FIG. 2(1), (b) shows a command signal. According to the illustrated example, it is a pulse width modulated signal of data of each bit comprising a command with “1” showing the low level and “0” showing the high level. The modulator circuit 103 uses the command signal to modulate (ASK modulation) the carrier wave to generate a transmission signal (c). According to the illustrated example, ASK modulation with degree of modulation 10% is carried out. The generated transmission signal is provided to the antenna coil 11 after undergoing an amplification process by the tuning-amplifying circuit 105 and an impedance matching process by the Z conversion circuits 104, 106 and 101 and transmitted to the tag 2 as electromagnetic waves. As the control part 21 of the tag 2 demodulates the transmission signal from the reader-writer 1 and recognizes the contents of the command, it carries out a process corresponding to this command and generates a response that shows the results of this process. In order to return this response, the control part 21 switches the load switch 25 on and off on the basis of the data arrangement as shown in (d) and (e) of FIG. 2(2). In this example, the length of time for transmitting a bit of signal is set equal to the time necessary to repeat the switching on and off of the load switch 25 sixteen times. If the data item to be transmitted is “0”, the load switch 25 is switched on and off eight times during the first half of the aforementioned length of time and the load switch 25 remains switched off during the second half. If the data item to be transmitted is “1”, on the other hand, the load switch 25 is kept switched off during the first half and the load switch 25 is switched on and off eight timed during the second half of the period. When the reader-writer 1 and the tag 2 are in a relationship where communication is possible, their antenna coils 11 and 23 are in an electromagnetically coupled condition. Thus, as the impedance of the tag 2 is periodically changed by the switching of the load switch 25 on and off, the impedance of the reader-writer 1 also changes accordingly, causing also the current that flows through its antenna coil 11 to change. The receiver circuit 13 serves to detect from this change a signal that represents the aforementioned response, eliminating noise by means of the bandpass filter circuit 107 and thereafter extracting by means of the detection circuit 108 the carrier wave that has been affected by the aforementioned changes in impedance. After the frequency components of the carrier wave are further eliminated by means of the low pass filter circuit 109, an amplification process is carried out by means of the amplifier circuit 110 such that a reception signal (f) as shown in FIG. 2 is detected. The frequency of the reception signal (f) after the frequency component of the carrier wave is removed is 424 KHz. The reception signal corresponding to the period during which the load switch 25 is switched on and off (data signal) includes waves which have an amplitude greater than a specified value and change in synchronism with this switching. Waves with an amplitude greater than the specified value also appear due to noise in the environment in the reception signal while the load switch 25 is maintained in the off-condition (base signal). The comparator circuit 111 compares the amplitude of this reception signal with a specified reference level and generates a binary signal (g) in FIG. 2. By this binarization process, a signal change corresponding to the switching of the load switch 25 is extracted. The control part 10 partitions this binary signal (g) in units of bits and thereby obtains a demodulated signal (h), demodulating the data of the individual bits. The detection circuit 112 of the level extracting circuit 18 takes in the reception signal (f) of FIG. 2 and extracts an envelope that includes each peak of the reception signal as shown in FIG. 3. This envelope signal is converted into a digital signal by means of the A/D converter circuit 113 and inputted to the control part 10. The control part 10 makes use of this input from the level extracting circuit 18 to obtain information indicative of the noise level immediately before and during a communication and carried out a process of reporting this to the user. The reader-writer 1 starts a communication with the tag 2 as it receives a command (such as a read command or a write command) from a host apparatus and provides the tag 2 with a similar command. As the tag 2 carries out a process according to this command and returns a response, the reader-writer 1 transmits this response back to the host apparatus. In general, a plurality of tags 2 are sent into the communication region of the reader-writer 1 sequentially at specified intervals. Each tag stops at a position opposite the reader-writer 1 for a specified length of time during which a communication process is carried out according to a flow as shown in FIG. 4. The arrival of a tag 2 at the opposite position of the reader-writer 1 is detected by means of a sensor (not shown). The host apparatus inputs its detection signal and outputs a command to the reader-writer 1. The size of the communication region is determined based on the range in which power necessary for communication with the tag 2 can be induced. When the tag 2 enters this communication region, it comes to be in the condition capable of responding to a command from the reader-writer 1. FIG. 4 shows this flow of communications among the reader-writer 1, the tag 2 and a host apparatus. Line (1) shows the signals exchanged between the host apparatus and the reader-writer 1, Line (2) shows the signals transmitted from the reader-writer 1 to the tag 2, and Line (3) shows the signals transmitted from the tag 2 to the reader-writer 1. The portions shown by dotted lines indicate periods during which data are being processed (command analysis or response analysis) by the reader-writer 1 or the tag 2. Whether it is a command analysis or a response analysis that is being carried out is also indicated. In what follows, the flow of basic data processing for the tag 2 will be explained with reference to reference symbols A, B, etc. of FIG. 4. Firstly, the host apparatus generates a command showing processes to be carried out by the tag 2 and transmits it to the reader-writer 1 (A). After analyzing the content of this command, the reader-writer 1 transmits to the tag 2 a first data readout command (B). In the above, the first data readout is for the purpose of acknowledging the fixed data such as the identification data of the tag 2 and is commonly referred to as the “system read”. While this system read is being carried out, the tag 2 receives signals of the system read through the antenna coil 23 which is electromagnetically coupled to the antenna coil 11. After acknowledging and analyzing the system read command, the tag 2 generates a response including specified data and returns it to the reader-writer 1 (C). The beginning portion (shown with a hatching) of this response (C) contains a fixed data arrangement of several bits. This portion is for indicating that the data which follow are the response from the tag 2 to this system read and is referred to as the “start code”. While this response (C) is being transmitted, the reader-writer 1 receives signals of this response through the antenna coil 11 electromagnetically coupled to the antenna coil 22. The reader-writer 1 analyzes the content of the received response and if it is judged to be a normal response, a second command is transmitted to the tag 2 (D). The purpose of this second command is to provide the tag 2 with the content of the command (A) from the host apparatus and to thereby cause this command to be executed. Thus, this command is hereinafter referred to as the execution command. After, analyzing this execution command and executing the process corresponding to its content, the tag 2 generates a response that indicates the details of the process and returns it to the reader-writer 1 (E). Upon recognizing that the response from the tag 2 is normal, the reader-writer 1 transmits it to the host apparatus (F). In the reception signal detected by the receiver circuit 13, as shown in FIG. 2, there is a big difference between the data signal corresponding to a period when a data communication from the tag 2 is being carried out (when the load switch 25 is being repeatedly being switched on and off) and the base signal while no data communication is taking place (while the load switch 25 is maintained in the switched-off condition) and hence the transmission data from the tag 2 can be correctly demodulated by a binarization process. If large noise appears suddenly during a communication process with the tag 2, however, a level change exceeding the binarization threshold value may appear in the base signal and there is a possibility that the transmission data cannot be demodulated correctly. In view of this problem, the reader-writer 1 is provided with the function of reporting on the level of noise that may be present at the time of communication processing. In what follows, two examples of this reporting function will be described sequentially. According to the first example, the level of the signal extracted by the level extracting circuit 18 is checked before the communication with the tag 2 is commenced and under the condition where the tag 2 is not inside the communication region of the reader-writer 1. Since the aforementioned carrier wave is constantly being transmitted independently of the communication with the tag 2, the changes in the level of the reception signal when the tag 2 is not inside the communication region and is not engaged in any communication should be reflecting the condition of the noise. Since the level extracting circuit 18 is adapted to extract the level when the reception signal shifts in the higher direction, it can extract the level reflecting the size of noise when no communication is being carried out. In what follows, the level which is extracted by the level extracting circuit 18 under the condition where no communication is being carried out will be referred to as the noise level. The control part 10 carries out the process of sampling the noise level a plural number of times before a communication is carried out, calculates an average value of the sampled values and causes it to be displayed on the display part 15. FIG. 5 is a flowchart showing a detailed control routine by the reader-writer 1. In FIG. 5, N(i) indicates an arrangement for storing the sampled values of noise level. This routine is started as a command (A) is received from a host apparatus and the counter i is initially set to zero (Step ST1). Thereafter, in the loop of Steps ST2-ST5, input data from the level extracting circuit 18 are taken in (Step ST2) for a specified number of times (100 times in the illustrated example) and each of these inputted values is stored in a memory as noise level N(i) (Step ST3). After all these noise level values are inputted (YES in Step ST5), the average value Nav of these 100 noise level values N(i) is calculated (Step ST6) and displayed by the display part 15 (Step ST7). The display part 15 may be adapted to display the numerical value of this average Nav itself or to use a bar graph to make a display in comparison with a specified threshold value. After the series of processes described above has been completed and the tag 2 has entered the communication region of the reader-writer 1, the series of communications with the tag 2 as shown in FIG. 4 is started (Step ST8). The aforementioned display of the average value Nav is continued until the communication process is completed or even until the next command is received from the host apparatus after the communication process is completed such that the user will have sufficient time to notice the display. In the case of the occurrence of a communication error, not only it is reported by means of an alarm but also the display of the average value Nav is continued for a specified length of time. By a control as described above, the user can be informed of the level of noise that is being generated immediately before each of the communication processes. Especially when a communication error has occurred, the user can easily determined whether this error was a result of noise or not. The second of the examples to be described next is for processing a reception signal being exchanged between the tag 2 after the tag 2 has entered the communication region of the reader-writer 1 and has started a communication process. Explained in detail, this is done by taking note that the aforementioned start code is included at the beginning of the response from the tag 2, extracting the rate of level change in the reception signal corresponding to this start code a signal-to-noise (SN) ratio and causing it to be displayed by the display part 15. FIG. 6 shows an example of this signal processing on the start code. The timing chart in FIG. 6 shows the correspondence between a portion of data contained in the response from the tag 2 and the on/off operations of the load switch 25. The portion of the reception signal on the side of the reader-writer 1 corresponding to data item “0” of this response is shown enlarged. This also shows a level change reflecting the on-off operations of the load switch 25. In other words, this level change is extracted by using the envelope signal extracted by the level extracting circuit 18. Since the data arrangement of the start code is known, the control part 10 can separate this reception signal into a portion that corresponds to the aforementioned data signal and another portion that corresponds to the base signal by comparing between the data arrangement of the reception signal binarized by the comparator circuit 111 of the receiver circuit 13 and the aforementioned known data arrangement. According to this example, while a signal corresponding to the start code is being received, the envelope signal extracted by the level extracting circuit 18 is separated into signal PS corresponding to the data signal and signal PN corresponding to the base signal, the average value of signal PS is treated as the signal level S, the average value of signal PN is treated as the noise level N and their ratio is calculated. FIG. 7 shows the routine according to the second example. This routine is also started as a command is received from a host apparatus, and a command for the aforementioned system read is transmitted to the tag 2 (Step ST11). After a response to this command is received from the tag 2 (or when the starting bit of the start code of this response is recognized) (YES in Step ST12), the process of detecting the start code as a whole is continued (Step ST13). In this step, the data arrangement corresponding to the start code is recognized on the basis of the binary signal from the comparator circuit 111. At the same time, the output from the level extracting circuit 18 corresponding to the start code is taken in while it is separated into aforementioned signals PS and PN and storing them in a memory (not shown). After the start code is thus detected, the processing of Steps ST14-ST16 and that of Steps ST17 and ST18 are carried out in parallel. In Step ST14, average values of signal levels that have been accumulated separately for signals PS and PN extracted in Step ST13 are obtained to determine signal level S and noise level N as defined above. The SN ratio is calculated by dividing the noise level N by the signal level S (Step ST15) and is displayed by the display part 15 (Step ST16). In Step S17, on the other hand, the substantial content of the response is obtained from the portion of the reception signal after the start code detected in Step ST13 and this content is analyzed. Thereafter, the remainder of the communication process such as the transmission of the execution command, the reception of a response from the tag 2 to this command and the transfer of this response to a host apparatus is carried out (Step ST18). In this example, too, the display of the SN ratio is continued until the process of Step ST18 is completed or until a next command is received from the host apparatus. In the case of the occurrence of an error, an alarm is outputted to report it and the display of the SN ratio is maintained for a specified length of time. By this second example, since the SN ratio can be displayed during a communication process, the user can ascertain the level of noise that is being generated while carrying on the communication process. In the case of a communication error, in particular, it can be ascertained easily whether this error was caused by noise or not from the displayed SN ratio. As a variation of the second example, the difference between the signal level S and the noise level N may be obtained instead of their ratio. Although it was explained above that Steps ST14-ST16 and Steps ST17 and ST18 are carried out in parallel, the step of analyzing the response (Step ST17) and the step thereafter may be carried out after the SN ratio has been obtained. In such a case, the routine may be so arranged that the step of analyzing the response (Step ST17) and the steps thereafter are stopped if the calculated SN ratio happens to exceed a specified threshold value. Since communications under a condition of large noise can thus be avoided in this manner, communications can be carried out successfully with a higher level of reliability. After the communication process is thus stopped, it is preferable to restart the same routine from the beginning after a specified length of time has elapsed. By both of the examples described above, communication processes can be carried out by sending tags 2 sequentially into the communication region of the reader-writer 1 and noise level and SN ratios can be calculated and displayed on the display part 15 between or during these processes. The selection between the two examples may be made, depending upon the time difference between when a tag which has completed its communication leaves the communication region of the reader-writer 1 and when the next tag arrives in the communication region and the processing time assigned to each tag. If this time difference is sufficiently long, the first example may be used. If this time difference is small, the second example may be used. The control according to either of the examples may be carried out not only during a real operation but also during a preliminary test period. In such a case, the user can estimate the level of noise that is likely to be generated from the display of either the noise level or the SN ratio such that the environment can be rearranged if this level is found to be too high. Since the signal level is expected to become lower as the tag 2 is separated from the reader-writer 1 farther away especially in the case of the second example, the distance between the reader-writer 1 and the tag 2 can be adjusted on the basis of the displayed SN ratio. Each of the examples described above was designed such that the communication process is carried out after the tag 2 entering the communication region of the reader-writer 1 is stopped but there are cases where the communication process is carried out while the tag 2 is in motion. In such a case, the reader-writer 1 carries out the aforementioned system read repeatedly until a response is obtained from the tag 2 and transmits the execution command if a response is obtained from the tag 2, concluding that it has become possible to communicate with the tag 2. When the first of the examples described above is applied to such a case, the process of detecting the noise level is carried out immediately before every system read such that, at the point in time when a response from the tag 2 is obtained to a system read, the noise level which was obtained immediately before or the average value of noise levels obtained by a plurality of detection processes in the recent past may be displayed. In the case of the second example, the noise level may be detected after a response is obtained from the tag 2 and a routine which is similar to the one according to FIG. 7 but in which the system read is repeated may be carried out. The noise level and the SN ratio obtained as explained above may be outputted to a host apparatus instead of being displayed. In such a case, the host apparatus will be able to carry our controls such as displaying the transmitted data from the reader-writer 1, determining the size of noise and outputting an alarm in the case of a large noise. The reader-writer 1 may be adapted to create history data by correlating the calculated results of noise level and SN ratio each time with the results of the communication process and to store them in a memory. FIG. 8 shows an example of such history data, correlating the results of each communication process with the noise level measured immediately before that communication result. These noise levels are values measured before the communication process is started and under the condition where the tag 2 is not inside the communication region of the reader-writer 1, similar to the first example described above. For the measurement of these noise levels, a routine similar to Steps ST1-ST6 of FIG. 5 may be repeated for a plural number of cycles but it is preferable to adopt as the history data the noise levels measured immediately before a communication process. In this example, data related to each of communication processes are collected as a page and each page is assigned a number (page number) indicative of the cycle (how many cycles before) in which the data were obtained in the communication process. The page number is 1 for the communication process carried out immediate before and is increased as the time goes farther back. In other words, every time a communication process is carried out, the number of the page related to the communication process immediately before is set to 1 and the numbers of older pages are incremented by 1. Each page contains not only data read out of the tag 2 as data showing the results of a communication but also data item “normal” or “abnormal” to indicate whether the communication process was successful or not. In this example, it is so arranged that in the case of a failure in the communication a retry (the process of repeating the same communication again) can be carried out up to a predetermined number of times and if the communication succeeds by a retry, the data item showing the result will say “normal”. If the communication does not succeed after the retry is repeated for the predetermined number of times, the result is shown as “abnormal”. Explained more in detail, the data items “normal” and “abnormal” are expressed by a flag. Although not shown in FIG. 8, the number of times a retry was repeated may also be included in the result of communication. Although the data read out from the tag 1 are 8-bit data, data with the upper 4 bits and the lower 4 bits separated are also stored in order to show them as hexadecimal data (“base 16”). In the example of FIG. 8, the original 8-bit data are shown as “raw data” and the upper and lower 8-bit data are shown in hexadecimal notation. For noise level, too, not only raw data in 8 bits but also data in hexadecimal notation (“base 16”) are stored in order to show the upper and lower 4-bit portions separately. The noise level is also shown in terms of being “large” or “small” and this determination is shown in the table. This determination may be made by comparing the calculated noise level with a specified threshold value. In addition to “large” and “small”, another classification “medium” may also be introduced to indicate that the noise level is somewhere between “large” and “small”. These results of determination are also indicated by means of a flag. The reader-writer 1 is adapted to transmit the history data to a host apparatus in response to a call command therefrom. The host apparatus may display the transmitted history data on a display device or carry out a process of printing them out such that the user can analyze the cause of a communication error in detail from such outputted history data. From the data shown in FIG. 8, for example, it may be concluded that a communication error occurred because of noise in the communication process corresponding to page number 11 and that the communication error in the communication process corresponding to page number 50 was not because of noise but was due to some other cause such as an inadequate position of the tag 2 or a fault in a circuit on the side of the tag 2. If history data of operations of apparatus set near the reader-writer 1 are stored (say, by a host apparatus), the cause of occurrence of noise may be analyzed on the basis of the conditions of operations of such other apparatus when there is a communication error due to noise. If it is found that there is a high probability that a certain apparatus is in operation at the time of occurrence of a communication error, it may be predicted that this apparatus is the cause of noise and a proper measure may be taken to reduce the noise. The first example shown in FIG. 5 was explained above as detecting a noise level before the start of a communication, reporting its result and always restarting the communication after the elapse of a certain specified length of time. Instead, it may be arranged to wait until the noise level becomes low if it is found to be above a specified threshold value. FIG. 9 shows a control routine for such an arrangement. The routine according to FIG. 9 is also started as a command is received from a host apparatus. At the start of this routine, the counter i for counting the sampling number of noise level is set to zero (Step ST21) and the output value from the level extracting circuit 18 is detected and stored as the noise level N(i) (Step ST22). If this value is less than a specified threshold value N0 (YES in Step ST23), the counter i is incremented by 1 (Step ST24). If N(i) is not less than the threshold value N0 (NO in Step ST23), the counter i is reset to zero (Step ST26). The above is repeated until the counter value i reaches 100, or until all of 100 consecutively sampled noise levels are found to be below the specified threshold value N0 (YES in Step ST25) and it is only then that the communication process is started (Step ST27). By this routine, a communication error due to noise can be avoided with a high level of reliability. The example described above with reference to FIG. 9 is somewhat similar to the prior art disclosed in aforementioned Japanese Patent Koho 9-190518 in that communications are started only after it is ascertained that noise level is low. According to the prior art technology of Japanese Patent Koho 9-190518, however, it is necessary to carry out a communication with the tag in order to check the noise level and two correlation calculations must be performed in order to check the noise level. According to the present invention, by contrast, the process is not complicated because only the noise level is checked and there is no particular need to carry out any communication with the tag. Moreover, the technology according to Japanese Patent Koho 9-190518 does not require that the condition of a low noise level should continue for a specified length of time. Although the noise level may happen to be low some time before the start of a communication, noise level may suddenly rise thereafter to cause a communication error. According to the example shown in FIG. 9, by contrast, a communication process is not started unless the condition of low noise level lasts for a specified length of time. Thus, communications are be started under a more reliably stable condition and it is much less likely that the noise level will rise suddenly during a communication. In other words, communication errors caused by noise can be avoided much more reliably. | <SOH> BACKGROUND OF THE INVENTION <EOH>This invention relates to a read-write processing apparatus for carrying out non-contact communications with an RFID tag containing a semiconductor memory to read out or write data from or into this memory and a read-write method that is carried out by such an apparatus. Systems having a memory medium storing various data attached to each article to be transported and being adapted to read and write data from and into this memory medium by wireless communications are coming to be introduced into control sites of cargoes and assembly lines of factories. Such a system is referred to as an RFID (radio frequency identification) system and the aforementioned memory medium to be attached to each article to be transported contains an IC chip containing a semiconductor memory and a communication antenna coil and is commonly referred to as an RFID tag or a non-contact IC tag. Prior art read-write processing apparatus for an RFID system are structured as a reader-writer having both an antenna part and a control unit inside a same housing structure, as a controller separate from an antenna part or as a controller that contains the transmission-reception circuit and the control part of the antenna part. Both when reading and writing data, prior art read-write processing apparatus are adapted to transmit a command of a specified format to an RFID tag and to receive from the RFID tag a response to this command. When an RFID tag without containing an inner power source is used, an induced electromotive force is generated in the antenna coil on the side of the RFID tag by means of transmission waves from the antenna part such that a control circuit inside the RFID tag will be driven. With an RFID system as described above, there is a high probability that various kinds of noise will come to be mixed in the communication region for the tag and the antenna part so as to cause communication errors since the system is often introduced in an environment where machines and apparatus of various types are installed. For this reason, it is necessary to carry out test communications prior to actual system operations and to thereby check whether or not the system is in a condition capable of carrying out communications with RFID tags without any trouble. In view of the above, the present applicant has earlier proposed a read-write processing apparatus provided with a test mode in which a read-write process is carried out and the distance to the tag is adjusted, and a display light is switched on if a communication error occurs. (See Japanese Patent Koho 2,610,897). By the invention of aforementioned Japanese Patent Koho 2,610,897, the user can conclude that the antenna part and the RFID tag are in a condition for communicating to each other if this display light is not lit. When such an RFID system is put in an actual use in a real situation, however, there is a possibility of a communication error due, for example, to a sudden occurrence of noise, say, because of the operations of surrounding machines. It is difficult to predict, however, when and how such sudden noise may occur and the real situation is that no sufficient measure is being taken against noise. In view of this, Japanese Patent Koho 9-190518 discloses a method according to which the read-write processing apparatus transmits to the RFID tag a command to request for the transmission of a pseudo random signal and correlation values are obtained with two kinds of reception signals to this command (signals with data arrangement similar to and not similar to that of the transmission signal from the RFID tag). Only if the correlation value C 1 with the signal similar to the transmission signal is greater than a first threshold value T 1 and the correlation value C 2 with the signal not similar to the transmission signal is less than a second threshold value T 2 , an access is allowed for reading out data. According to the invention of aforementioned Japanese Patent Koho 9-190518, reliability of communication process can be improved because actual communication can be started only after it is ascertained that the noise level is low. This invention has problems, however, in that the process becomes complicated because special communications must be carried out between the read-write processing apparatus and the RFID tag for checking the status of noise and that the read-write processing apparatus is required to carry out two correlation calculation processes. Under a circumstance where the variations of noise are large, furthermore, although a communication process may be started after it is ascertained that the two correlation values C 1 and C 2 both satisfy the aforementioned conditions, there may arise a sudden change in the noise and a communication error may result. Moreover, communication errors are not limited to be caused by noise but may be caused also for reasons other than noise such as a fault in the RFID tag. In the situation of a communication error, prior art systems inclusive of those according to aforementioned Japanese Patents Koho 2,610,897 and 9-190518 are not adapted to check whether or not it was caused by noise. | <SOH> SUMMARY OF THE INVENTION <EOH>It is therefore an object of this invention to make it possible for the user, when a communication error has occurred in a communication process with an RFID tag, to easily ascertain whether this error was due to noise or not. It is another object of the invention to prevent the occurrence of a communication error with a high level of reliability by stopping the communication or preventing the start of a communication under a condition of a high noise level. This invention relates to a read-write processing apparatus for communicating with an RFID tag provided with a semiconductor memory to read and write data from and into this semiconductor memory, preferably equipped with a control part comprising a computer. Such a read-write processing apparatus may be formed as a reader-writer having an antenna part for communicating with the RFID tag (inclusive of an antenna coil as well as a transmitter circuit and a receiver circuit for signals) inside a same housing structure but is not so limited. It may be structured as a controller separate from such an antenna part. It may also be structured as a controller that contains the transmitter and receiver circuits of the antenna part. Since the RFID tag is set so as to operate according to a command from the read-write processing apparatus, reception signals under a condition where no command is being transmitted do not contain any transmission signal from the RFID tag. Thus, the amplitude of variations in the reception signal may be considered to reflect the noise level. A read-write apparatus according to a first embodiment of this invention was conceived in view of the above and comprises wait condition setting means for setting prior to a communication with the RFID tag a wait condition under which only a carrier wave is transmitted, noise level extracting means for extracting as noise level a level from a reception signal obtained under this wait condition, and reporting means for displaying or outputting this extracted noise level. The wait condition setting means can cause the antenna part to transmit only the carrier wave by not outputting any data that form a command. The noise level extracting means includes preferably a level extracting circuit (having a detection circuit and an A/D converter circuit) for processing a reception signal, as well as a signal processing part for processing the output from the level extracting circuit. The level extracting circuit is adapted to extract the level of an envelope line of this reception signal by means of its detection circuit. The signal processing part may be structured so as to take in the output from the level extracting circuit for a plural number of times, to obtain their average and dispersion values and to determine the noise level from the results of its calculations. The wait condition setting means and the signal processing part may be formed by installing a program necessary for their processing into the computer that comprises the aforementioned control part. The level extracting circuit may be provided independently of an ordinary receiver circuit. If the read-write processing apparatus is structured as a controller separate from the antenna part, the level extracting circuit may be contained in the housing structure for the antenna part. In such a case, the level extracting circuit is not contained by the noise level extracting means and the level extracting means may be formed with an input part for taking in the output from the level extracting circuit and the aforementioned signal processing part. If the reporting means is formed as a displaying means, the noise level may be shown as a numerical value but it may also be shown as an analog display such as a bar graph. The noise level may also be displayed in several steps such as levels 1 , 2 , 3 , etc. Such display means may be set on the surface of a housing structure forming the main body of the read-write processing apparatus. If the reporting means is formed as outputting means for outputting the noise level to the outside, it may be formed as an output interface of a personal computer or a programmable logic controller (PLC) to a host apparatus. This output need not be digital signals. This may be outputted as an analog signal. With a structure as described above, a wait period of a specified length can be set before a communication is started as the condition for a start of such a communication with the RFID tag such as the receipt of a command from a host apparatus comes to be satisfied. Thus, the noise level can be extracted during this period and the result of the extracted level can be reported to the user. In the case of a communication error, the user can easily ascertain whether the error is due to noise or not from the noise level that has been reported. According to a preferred embodiment, the read-write processing apparatus of this invention may further comprise history data memory that stores history data on processes of each time and storing means for storing the extracted noise in the history data memory in correlation with data that indicate success and failure of communication with the RFID tag. With an apparatus thus structured, history data correlating the noise level extracted immediately before the communication of each time with a success or a failure of the communication can be stored. Thus, the user can make use of such history data to recognize the noise level when a communication fails and investigate the cause of the failure in the communication. If data indicative of date are correlated in the history data and a host apparatus stores history of operations of apparatus near the read-write processing apparatus and the RFID tag, for example, the source of noise for a communication error under a condition of high noise level can be estimated from the status of the site at the time of the occurrence of the error. If the history of operations of peripheral apparatus is separately accumulated, in particular, causal relationships between the communication process and the peripheral apparatus may also be estimated and an apparatus that was operating at the time of occurrence of the error may be picked as a candidate to the source of error. The response returned by the RFID tag to the read-write processing apparatus includes both a portion where the impedance in the tag is switched at a specified frequency and a portion where the impedance switching does not take place. Data that form a response are an arrangement of “1”s and “0”s in a specified order but data are each expressed as a combination of a part where the impedance is switched and a part where the impedance is not switched. In the reception signal to the response on the side of the read-write processing apparatus, a signal with large changes in the level (hereinafter referred to as the data signal) appears during a period when the impedance is being switched and a signal with small changes in the level (hereinafter referred to as the base signal) appears during a period when the impedance is not being switched. The read-write processing apparatus can separate the data signal and the base signal in the receiving circuit by carrying out a binarization process on the demodulated reception signal but if there is a large level change in the base signal due to noise, the difference between the data signal and the base signal becomes small and a possibility of a communication error arises. A read-write processing apparatus according to a second embodiment of this invention was conceived in view of the above and comprises signal extracting means for extracting level of a data signal (as defined above) and level of a base signal (as defined above) from a signal being received in a communication process with the RFID tag, calculating means for calculating the ratio or the difference between the levels of the data signal and the base signal, and reporting means for displaying or outputting the result of calculation by the calculating means. The signal extracting means in the above, like the noise level extracting means of the read-write processing apparatus according to the first embodiment, may include a level extracting circuit and a signal processing part. The signal processing part is preferably adapted to carry out the extraction of signal level while known data are being transmitted from the RFID tag. As for the known data in the above, it is preferable to use the fixed data positioned at the front part of the response. The fixed data in the above, referred to as the start code, are for the purpose of showing that it is a response from the RFID tag, and generally data of a specified number of bits are arranged in a given sequence. When the signal level of a period during which the start code is being transmitted is extracted, the signal processing part can recognize a period during which a signal corresponding to the start code is being inputted on the basis of an input from the receiver circuit and input the levels of a data signal and a base signal during this period extracted by the level extracting circuit. In this case, the level of the signal extracted from the data signal corresponds to the aforementioned period during which the RFID tag is switching the impedance periodically and the level of the signal extracted from the base signal corresponds to the aforementioned period during which the RFID tag is not switching the impedance periodically. For each of the base signal and the data signal, it is preferable to repeat the sampling for a plural number of times and to determine the signal level on the basis of the average or dispersion value of the sampled values. The calculating means may be set by installing a program necessary for the control but may be structured as an IC chip incorporating a divider circuit or a subtractor circuit. The reporting means may be structured like the reporting means for the first read-write processing apparatus described above. With the second read-write processing apparatus described above, a numerical value representing the ratio or difference between the levels of a data signal and a base signal in a signal being received during a communication with the RFID can be obtained and reported to the user. Thus, when there is a communication error, the user can easily determine whether the error was caused by noise or not on the basis of the reported numerical value. When a report is made to the user, it need not be the numerical value itself that should be displayed but may be analog data such as a bar graph. With the second read-write processing apparatus described above, the level of a signal extracted from a data signal becomes lower as the RFID tag moves farther away from the antenna coil of the read-write processing apparatus but it may be considered that no large change will appear in a signal extracted from a base signal. In other words, it may be thought that the difference in the levels of these two kinds of signals will become smaller as the distance (communication distance) between the antenna coil and the RFID tag becomes greater. Thus, this read-write processing apparatus may be used to check the adequacy of the communication distance from the reported result of the calculation when a test communication is carried out for adjusting the communication distance. It is preferable to further provide the read-write processing apparatus according to the second embodiment of the invention with communication control means for comparing a numerical value obtained by the calculating means with a specified threshold value and stopping the communication process when the numerical value changes so as to cross the threshold value. Thus, the communication control means can stop the communication process on the basis of the calculations by the calculating means if the numerical value obtained by the calculating means changes so as to cross the threshold value either from above to below or from below to above. If the calculating means is adapted to divide the level S extracted from a data signal by the level N extracted from a base signal, for example, the communication process can be stopped when the ratio S/N thus obtained changes from a value greater than the threshold value to a smaller value than the threshold value because the ratio becomes smaller as the value of N increases. This communication control means, too, can be set by installing a program necessary for the control. The communication process can be stopped by this means when a large noise occurs suddenly and hence the occurrence of a communication error due to such noise can be prevented. It is preferable to arrange such that a stopped communication process will be restarted after the elapse of a specified length of time. It is also preferable to further provide the read-write processing apparatus according to the second embodiment of the invention with history data memory that stores history data on processes of each time and storing means for storing the result of calculation by the calculating means in the history data memory in correlation with data that indicate success and failure of communication with the RFID tag. This memory and the storing means may be similar to those described above for introducing to the read-write processing apparatus according to the first embodiment of the invention. Thus, the user can estimate the source of noise that caused a failure in a communication by analyzing these history data. A read-write processing apparatus according to a third embodiment of this invention is characterized as comprising wait condition setting means for setting a wait condition prior to a communication with the RFID tag, only a carrier wave being transmitted under this wait condition, noise level extracting means for extracting as noise level a level from a reception signal obtained under the wait condition, and communication control means for discontinuing the wait condition and starting a communication with the RFID tag after a condition in which the noise level remains smaller than a specified value has continued for a specified length of time. The wait condition setting means and the noise level extracting means in the above may be similar to those comprising the read-write processing apparatus according to the first embodiment of the invention described above. It is preferable in the above, however, to make the wait condition to last not for a fixed length of time but for an adjustable length of time. In particular, it is preferable to make it adjustable such that a clock that measures the time is reset to zero when the noise level becomes greater than the aforementioned specified value and the wait condition lasts until the condition with a low noise level has continued for a specified length of time. In this way, the start of a communication process can be made to wait until a condition with a stable noise level is regained and the occurrence of a communication error can be prevented. The communication control means of this embodiment can also be set by installing a necessary program in the control part as in the case of the read-write processing apparatus according to the second embodiment of the invention. The invention also relates to a method of communicating with an RFID tag provided with a semiconductor memory to read and write data from and into the semiconductor memory. A method according to a first embodiment of this invention comprises the steps of setting a wait condition prior to a communication with the RFID tag, only a carrier wave being transmitted under this wait condition, extracting as noise level a level from a reception signal obtained under the wait condition, and displaying or outputting the extracted noise level. This method may be interpreted as the method carried out by the read-write processing apparatus according to the first embodiment of the invention described above although these steps can be carried out by different devices. For example, the read-write processing apparatus may be used for the first two steps and the third step may be carried out by a personal computer or the like. A method according to a second embodiment of this invention comprises the steps of extracting level of a data signal and level of a base signal from a signal being received in a communication process with the RFID tag, the data signal and the base signal respectively corresponding to a period during which the RFID tag switches and does not switch impedance periodically, calculating the ratio or the difference between the levels of the data signal and the base signal, and displaying or outputting the result of calculation by the calculating means. This method may be interpreted as the method carried out by the read-write processing apparatus according to the second embodiment of the invention described above although these three steps may each be carried out by a different device. For example, the first step may be carried out by the read-write processing apparatus to output the two signal levels to another device such as a personal computer such that the second step and the third step may be carried out by such other device. By this invention, since the user is informed of the noise level when a communication is carried out with the RFID tag, the user can easily ascertain at the time of a communication error whether or not it is caused by noise. Moreover, if the noise level is high after a communication with the tag, the subsequent communication process may be stopped and it may be restarted again after a condition of a low noise level lasts for a specified length of time. Thus, the occurrence of a communication error can be prevented with a high level of reliability and a communication process can be carried out in a stable manner. | 20050121 | 20080902 | 20050804 | 75258.0 | 0 | DAGLAWI, AMAR A | READ-WRITE PROCESSING APPARATUS AND METHOD FOR RFID TAG | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,040,626 | ACCEPTED | Gain selected cell phone booster system | Apparatus for boosting the signal between a cell phone (14) and a cell site (16), which includes an amplifier (64) that continually operates at a fixed gain. A power detector (72) controls an attenuator (62) that can be switched to pass the amplified signal through an attenuator (74) of moderate resistance, or through an attenuator (60) of zero resistance so the power output is boosted within the limits allowed under cell phone system standards. | 1. A cell phone booster which is constructed to connect to a cell phone and to an antenna and which can boost a cell phone output signal that is generated by the cell phone for transmission by the antenna, wherein the booster includes a control that detects the strength of the cell phone output signal and that selects a level of amplification of the cell phone output signal that is delivered to the antenna, comprising: an amplifier which has an input coupled to said cell phone output, and which has an amplifier output; an attenuator apparatus which is connected in series with said amplifier and which is switchable between at least first and second discrete attenuation levels; a switch arrangement controlled by said control which selects one of said attenuation levels of said attenuator apparatus in response to the strength of said cell phone output signal. 2. The booster described in claim 1 wherein: said amplifier has a fixed gain which is in a linear region of the amplifier and including a tweaking resistance that is only manually adjustable at a factory but not during use of the booster. 3. The booster described in claim 1 wherein said cell phone is constructed for use under regulations that limit cell phone antenna output so it does not exceed about +30 dBm in any case, and so it does not exceed about −50 dBm when required by a cell site to transmit at minimum power, wherein: said amplifier output is of a strength to amplify the cell phone output by its maximum gain, and said control controls said attenuator apparatus to add zero attenuation when the cell phone output signal strength is above a minimum, so the output delivered to said antenna then is boosted by about the maximum amount over the output of said cell phone. 4. The booster described in claim 3 wherein: the second attenuation level is greater than zero dB attenuation, and said control connects said second attenuation level in series with said amplifier when the cell phone output signal strength is minimum, so the output delivered to said antenna device is then boosted by the minimum gain of the booster. 5. The booster described in claim 1 wherein: said control includes a circuit portion that prevents the switching of said attenuator apparatus from one of said attenuation levels to a second of said attenuation levels until the strength of said cell phone output signal has changed to a lower signal level than the signal level at which the attenuator apparatus was last switched. 6. The booster described in claim 1, wherein: said attenuator apparatus includes first and second resistances which create said first and second attenuation levels, said resistances each has first and second opposite ends, and said switch arrangement includes at least a first switch that is switchable between first ends of said first and second resistances. 7. A method for operating a cell phone booster which connects to a cell phone and to an antenna and which boosts the cell phone output signal from the cell phone and delivers the boosted signal to the antenna, comprising: detecting the strength of the cell phone output signal from the cell phone and using the detected strength to control the amplification of said cell phone output signal from said cell phone booster; operating an amplifier at a constant gain level; passing said cell phone output signal through said amplifier and through a changeable attenuator device that attenuates the signal passing through by an amount dependent on the detected strength of the cell phone output, and passing the signal that has passed through said amplifier and attenuator device to said antenna. 8. The method described in claim 7 wherein: said step of passing the cell phone output signal through a changeable attenuator device includes switching the attenuator device to pass the cell phone output signal through a selected one of a plurality of discrete attenuations. 9. The method described in claim 7 wherein operation of said cell phone requires that the booster output not exceed a maximum power level in any case, and not exceed a minimum power level when the booster must transmit at minimum power, and wherein: said amplifier has a fixed gain, and including switching selectable amounts of attenuation to maintain the booster output within the limits required by standards of the cellular industry. 10. A cell phone booster which is constructed to connect to a cell phone and to an antenna and which can boost a cell phone output signal that is generated by the cell phone for transmission by the antenna, wherein the booster includes a control that detects the strength of the cell phone output signal and that selects a level of amplification of the cell phone output signal that is delivered to the antenna, comprising: an amplifier apparatus which includes an amplifier, said amplifier apparatus has an input coupled to said cell phone output, and an output coupled to said antenna; a power detector and control circuit that generates a control signal that is dependent upon the power level from said cell phone; said power detector and control circuit controls said amplifier apparatus to produce a gain that has a predetermined discrete value that is dependent upon the output power from the cell phone, whereby continuously variable cell phone output power results in noncontinuous gain values for the amplifier. 11. The cell phone booster described in claim 10 wherein: said amplifier has a constant gain, and said amplifier apparatus includes a plurality of discrete attenuators that are connectable in series with said amplifier. | CROSS-REFERENCE This is a continuation-in-part of U.S. application Ser. No. 10/940,506 filed Sep. 14, 2004. BACKGROUND OF THE INVENTION Cell phone systems include base stations, or cell sites that control the output of cell phones. The control is such that if the cell phone is far from the nearest cell site the cell phone is directed to transmit at a high maximum amplitude, and so if the cell phone is close to the cell site the cell phone is directed to transmit at only a much lower maximum amplitude. TIA-98-E standards for the cell phone industry specify that maximum cell phone output cannot exceed +30 dBm (decibels above one milliwatt) even when the cell phone is far from the nearest cell site. Also, when the cell phone is near the cell site, the cell phone output cannot exceed −50 dBm (decibel below one milliwatt). The cell site controls cell phone output to comply with these standards. Boosters are available to amplify weak signals received from a cell site and to amplify the outputs of cell phones, when the cell site is far and the received signal is weak. Such boosters commonly use a system wherein the amplifier gain is continually variable, so when the received signal is strong the amplification is low and when the received signal is very weak the amplification is high, with the power output to the antenna always kept below the limit set by the cell site. One problem with such boosters is that continuously variable amplification increases non-linear response and results in emissions, adjacent channel interference, intermodulation and desensitization. Such boosters often satisfy unknowlegeable customers, who connect a cell phone through the amplifier and measure how much the signal strength increases (as seen on the cell phone received signal strength indicator). Such unknowlegeable customers do not realize that at low levels, the noise figure of the amplifier is the primary factor that determines sensitivity. Most available boosters transmit excessive power when close to a cell site, which severely disrupts proper cell site operation. A cell phone booster that provided maximum allowed cell phone transmission power output to a distant cell site, and maximum allowed output when close to a cell site to assure recognition, all while keeping transmitted signals within the limits set at every moment by the cell site, would be of value. SUMMARY OF THE INVENTION In accordance with one embodiment of the invention, a cell phone booster is provided, of a type that connects between a cell phone and an auxiliary antenna, which provides amplification of signals received from and transmitted to a cell site. This is accomplished with minimum distortion of signals to avoid breakup of weak signals, and while always transmitting within the power limits set by a cell site at any given time. The booster includes an amplifier which receives signals from the cell phone, attenuates them, and delivers them through an amplifier to the antenna. The amplifier is operated at a constant gain, in the linear range of the amplifier, to avoid distortion. The attenuator device has at least two attenuation levels (one of which can be zero), and a switch arrangement that routes the cell phone output through one of the selected attenuations. A control that detects the power level of signals allowed by the cell site, controls the switch arrangement to insert the lower level attenuation when the transmit signal strength allowed by the cell site is much greater than the cell phone actual output, which occurs when the cell site is distant. The control inserts the higher attenuation level when the allowed signal strength is only moderately greater than the cell phone actual output, which occurs when the cell site is close. The actual output of the cell phone (which is controlled by the cell site) is used to determine whether the cell site is far or close. The power level of signals allowed by the cell site is an amount that is 7 dB or 3 dB more than the cell phone output. As a result of tests of a wide variety of cell phones that applicant has made, applicant sets the amplifier to generate a gain of 7 dB and sets the attenuator to pass the signal to be transmitted though zero attenuation when the cell phone output is high. Applicant keeps the amplifier at the same gain of 7 dB but sets the attenuator device to pass the signal to be transmitted through a resistance (that produces an attenuation level) that produces a 4 dB loss for a total 3 dB gain, when the signal level from the cell phone output is low. This results in the signal to be transmitted always being amplified with minimum distortion, and results in transmitted signals that are always substantially within the limits set by the cell site. A control that controls operation of the switching arrangement that determines what attenuator is connected to the amplifier input, is connected to a power detector. If the power detector detects a high cell phone output (of at least 15 dBm) because the cell site is far away, the combination of amplifier and attenuator device produces a net gain of 7 dB (7 dB from the amplifier, which is not reduced by the attenuator device). That is, the output of the cell phone is amplified by 7 dB before delivery to the antenna. When the power detector detects a low cell phone output (of 7 dBm or less) because the cell site is close, an attenuation of 4 dB is connected and a net gain of 3 dB is produced. When the signal lies between 7 dBm and 15 dBm, the gain is not changed from what existed after the last change. This avoids frequent changing or oscillation between the two levels. The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of a cell phone booster of the present invention, shown installed in a vehicle and connected to a cell phone and to an antenna. FIG. 2 is a simplified schematic diagram of one embodiment of the booster of FIG. 1 FIG. 3 is a schematic diagram of the power detector and control of the booster of FIG. 2. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a booster 10 of the present invention, which is connected by coaxial cables to an antenna 12 and to an external antenna connection of a cell phone 14. One particular environment is where the cell phone lies in a vehicle and the antenna lies on the outside of the vehicle or against a glass pane, but the booster can be used in any other circumstance including a fixed installation to boost the capability of the cell phone. When the cell phone initiates a call, it transmits signals of increasing power until the signals are detected by a cell site 16. The cell site then transmits signals (digitally encoded signals) to the cell phone that control the power output of the cell phone. Thus, if the nearest cell site is distant, the cell site will control the cell phone to transmit strong signals, but no more than +30 dBm (30 dB above one milliwatt). If the cell site is close it will control the cell phone to transmit weak signals. For the case of a very close cell site, the cell phone output must not be more than −50 dBm. These limits of +30 dBm and −50 dBm EIRP (Effective Isotropic Radiated Power) are set by the TIA-98-E standard for CDMA (code division multiple access), which is the most widely used standard. These limits are used to assure that the cell site is not overwhelmed by a particular cell phone so the cell site does make the error of not detecting signals from other cell phones. The upper limit varies by category of cell phone and can be as high as about +38 dBm, so a limit of about +30 dBm includes the possibility of +38 dBm. It is to the advantage of the cell phone user that his/her cell phone transmit at the maximum level allowed by the standard and by the cell phone site that is controlling cell phone output. This increases the possibility that a signal from that particular user's cell phone will be detected and acknowledged by a distant cell site with minimum possibility of signal breakup when connected to the called party, and decreases the possibility that a close cell site will ignore the signal transmitted to it by reason of strong signals from other cell phones. Applicant has tested a wide variety of cell phones from many manufacturers. Applicant has found that when the tested cell phones were very near a cell site so their transmitted power must be a minimum, that the power output of almost all cell phones ranged from −53 dBm to −55 dBm. This is less than the maximum of −50 dBm allowed by the above-mentioned standards when the cell phone is very close to the cell site. Applicant also found that when the tested cell phones were so far from a cell cite that was in communication with the cell phone, that the signal was almost breaking up, that the power output of almost all cell phones was approximately +23 dBm. This is less that the maximum power of +30 dBm allowed by the above-mentioned standards. Applicant believes that the shortfalls are due to each cell phone manufacturer trying to be sure that all cell phones that it manufactures have outputs within the limits of the TIA-98-E standard despite variations in manufacturing tolerances, and to the manufacturers actually maintaining better tolerances than they allow for. However, few if any, cell phone customers complain about incorrect power. Applicant increases the usefulness of the cell phone by transmitting the cell phone output closer to the maximum power levels allowed by the above standard. As mentioned above, this minimizes breakup of signals to and from a distant cell site, and maximizes the likelihood of connection to a cell site that is experiencing high traffic and that has not provided sufficient bandwidth to accommodate all paying customers. FIG. 2 is a simplified schematic diagram of the circuit in the booster 10 of FIG. 1. Line 30 represents a coaxial cable or other line that connects a booster port 32 to a cell phone 14. The booster is constructed to operate in the 800 MHz band and in the 1900 MHz band. Assuming that the user decides to place a call, the cell phone delivers its output to a diplexer 40 that sends signals in the 1900 MHz band along path 42 and that sends signals in the 800 MHz band along path 44. Assuming the cell phone operates in the 800 MHz band, the cell phone signal passes though a duplexer 50 to its transmit, or TX output 52 (signals received from the cell site pass in the opposite direction through the duplexer 50 into the received, or RX input). The duplexer output 52 passes along path 56 through a zero attenuator 60 of a variable attenuator 62 device, or apparatus, and through an amplifier 64. The signal continues through a second duplexer 66 and second diplexer 68 and through a cable 69 to an antenna 70 which transmits to the cell site. The output of the cell phone begins at a low level and repeatedly increases until a cell site detects the signal. Thereafter, the cell site transmits signals that control the supposed output of the cell phone (which, in the prior art, has been below the level supposedly set by the cell site). The output of the cell phone 14 is detected by a power detector and control 72 that controls a switching arrangement 54 that, in turn, controls the attenuator device 62. In a system that applicant has designed, the attenuator device 62 has a second attenuator 74 that produces a 4 dB attenuation of signals passing though it. The attenuator 74 is preferably a pi resistor arrangement, although it is possible to use simpler resistive arrangements or capacitive or inductive impedances. If the power detector 72 detects an initial power level from the cell phone of under 7 dBm, the attenuator 62 is left with the 4 dB attenuator 74 connected between the cell phone and the amplifier 64. As a result of the 7 dB amplification by amplifier 64 but the 4 dB attenuation by attenuator 62, the output signal from the cell phone has been amplified by 3 dB by the time it reaches the antenna 70. If there is a later increase in cell phone output to 15 dBm or more, which is detected by the power detector, the switching arrangement switches to place the zero dB attenuator 60 in series with the cell phone and amplifier 64 (of course the 4 dB attenuator 74 is disconnected). Signals received from the cell site and picked up by antenna 70 pass through diplexer and duplexer 68,66 and pass though a low noise amplifier, or preamplifier 80 which amplifies the signal by 7 dB before passing the signal through duplexer and diplexer 50, 40 to the cell phone. The actual amplification of amplifier 64 is 7 dB plus cable, connector and circuit losses. The actual amplification of the amplifier is further adjusted for the efficiency of the antenna 70 (as compared to the cell phone antenna). The fixed amplifier gain is always in the linear portion of the amplification range. Since cable, connector and circuit losses vary and amplifier gain level for linear operation varies, an amplifier is chosen that produces a linear gain of more than 7 dB and a resistor (e.g. 102 in FIG. 3) is placed in series with the amplifier to reduce the net gain to 7 dB. Applicant notes that it often would be desirable to pass both the cell phone output and the output from the antenna though amplifiers that are both connected though the attenuator device 62. However, customers typically judge the benefit of the booster by viewing the signal strength indicator on their cell phone, and a constant high amplification (about 4 dB by amplifier 80) helps in marketing, but does not affect transmitted power. The switching of the attenuation between attenuators 60, 74 is done along the RF path, instead of by varying the DC input to the amplifier 64. This not only avoids non-linear responses and emissions, but avoids transients, and consequent annoying audio clicks generated by commonly used DC varying devices. FIG. 3 shows that the power detector and control circuit 72 of the booster of FIG. 2 includes a radio frequency diode 90 whose output at 92 is a DC voltage that increases with increasing power output of the cell phone. A comparator circuit 94 compares the voltage at 92 with the voltage of a reference source 96. The comparator 94 has an output 100 that controls operation of the switching assembly 54 that switches one or the other attenuator or attenuations 60, 74 of the attenuator device 62 in series with the amplifier 64. A factory-adjusted tweaking attenuator 102 is adjusted only when minimum gain is needed, to produce the desired amplifier output despite manufacturing tolerances. Applicant provides a plurality of descrete attenuations by attenuators 60, 74. There would be no reason to provide more than ten descrete attenuation levels. It is possible to provide a plurality of different attenuation levels with a single device such as a PIN diode that can be changed to fix a selected attenuation level, and which is the equivalent of a plurality of resistors or other attenuators. Thus, the invention provides a booster that improves operation of a cell phone by amplifying the output of the cell phone that is to be transmitted, and by amplifying the output of an antenna that is delivered to the cell phone. The output of the cell phone is amplified to levels close to the maximum levels allowed by industry standards. This is accomplished by use of an amplifier that operates at a constant gain so that it always operates in its linear range, and by the use of an attenuator device that produces a plurality of discrete attenuations, or impedances that are each preferably formed by resistances, and that can be selectively switched into series with the cell phone output that is to be transmitted. As a result of applicant's measurement of cell phones currently sold and the allowed maximum power allowed to be transmitted by cell phones under the extremes of conditions (weakest and strongest signals) applicant has chosen the amplification of the constant output linear amplifier so the minimum needed attenuation is zero. This minimizes current consumption when the cell site is distant. Applicant uses resistances that attenuate the amplifier output to produce gains of about 7 dB (6.25 to 7.75 dB, for the strongest cell phone output to a distant cell site) and about 3 dB (2.25 to 3.75 dB, for the weakest cell phone output to a close cell site). The switching assembly is controlled so switching from a first gain level to a second one, and switching back to the first one occurs only when the maximum or minimum level is exceeded by a plurality of decibels. Thus, for example, switching from 3 dB to 7 dB gain occurs only when a level of 15 dBm (or more) is detected by the power detector, and the booster is switched back to a 3 dB gain only when a level of 7 dBm (or less) is detected by the power detector. Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents. | <SOH> BACKGROUND OF THE INVENTION <EOH>Cell phone systems include base stations, or cell sites that control the output of cell phones. The control is such that if the cell phone is far from the nearest cell site the cell phone is directed to transmit at a high maximum amplitude, and so if the cell phone is close to the cell site the cell phone is directed to transmit at only a much lower maximum amplitude. TIA-98-E standards for the cell phone industry specify that maximum cell phone output cannot exceed +30 dBm (decibels above one milliwatt) even when the cell phone is far from the nearest cell site. Also, when the cell phone is near the cell site, the cell phone output cannot exceed −50 dBm (decibel below one milliwatt). The cell site controls cell phone output to comply with these standards. Boosters are available to amplify weak signals received from a cell site and to amplify the outputs of cell phones, when the cell site is far and the received signal is weak. Such boosters commonly use a system wherein the amplifier gain is continually variable, so when the received signal is strong the amplification is low and when the received signal is very weak the amplification is high, with the power output to the antenna always kept below the limit set by the cell site. One problem with such boosters is that continuously variable amplification increases non-linear response and results in emissions, adjacent channel interference, intermodulation and desensitization. Such boosters often satisfy unknowlegeable customers, who connect a cell phone through the amplifier and measure how much the signal strength increases (as seen on the cell phone received signal strength indicator). Such unknowlegeable customers do not realize that at low levels, the noise figure of the amplifier is the primary factor that determines sensitivity. Most available boosters transmit excessive power when close to a cell site, which severely disrupts proper cell site operation. A cell phone booster that provided maximum allowed cell phone transmission power output to a distant cell site, and maximum allowed output when close to a cell site to assure recognition, all while keeping transmitted signals within the limits set at every moment by the cell site, would be of value. | <SOH> SUMMARY OF THE INVENTION <EOH>In accordance with one embodiment of the invention, a cell phone booster is provided, of a type that connects between a cell phone and an auxiliary antenna, which provides amplification of signals received from and transmitted to a cell site. This is accomplished with minimum distortion of signals to avoid breakup of weak signals, and while always transmitting within the power limits set by a cell site at any given time. The booster includes an amplifier which receives signals from the cell phone, attenuates them, and delivers them through an amplifier to the antenna. The amplifier is operated at a constant gain, in the linear range of the amplifier, to avoid distortion. The attenuator device has at least two attenuation levels (one of which can be zero), and a switch arrangement that routes the cell phone output through one of the selected attenuations. A control that detects the power level of signals allowed by the cell site, controls the switch arrangement to insert the lower level attenuation when the transmit signal strength allowed by the cell site is much greater than the cell phone actual output, which occurs when the cell site is distant. The control inserts the higher attenuation level when the allowed signal strength is only moderately greater than the cell phone actual output, which occurs when the cell site is close. The actual output of the cell phone (which is controlled by the cell site) is used to determine whether the cell site is far or close. The power level of signals allowed by the cell site is an amount that is 7 dB or 3 dB more than the cell phone output. As a result of tests of a wide variety of cell phones that applicant has made, applicant sets the amplifier to generate a gain of 7 dB and sets the attenuator to pass the signal to be transmitted though zero attenuation when the cell phone output is high. Applicant keeps the amplifier at the same gain of 7 dB but sets the attenuator device to pass the signal to be transmitted through a resistance (that produces an attenuation level) that produces a 4 dB loss for a total 3 dB gain, when the signal level from the cell phone output is low. This results in the signal to be transmitted always being amplified with minimum distortion, and results in transmitted signals that are always substantially within the limits set by the cell site. A control that controls operation of the switching arrangement that determines what attenuator is connected to the amplifier input, is connected to a power detector. If the power detector detects a high cell phone output (of at least 15 dBm) because the cell site is far away, the combination of amplifier and attenuator device produces a net gain of 7 dB (7 dB from the amplifier, which is not reduced by the attenuator device). That is, the output of the cell phone is amplified by 7 dB before delivery to the antenna. When the power detector detects a low cell phone output (of 7 dBm or less) because the cell site is close, an attenuation of 4 dB is connected and a net gain of 3 dB is produced. When the signal lies between 7 dBm and 15 dBm, the gain is not changed from what existed after the last change. This avoids frequent changing or oscillation between the two levels. The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings. | 20050122 | 20070522 | 20060316 | 96334.0 | H04B700 | 1 | TRINH, SONNY | ENHANCED GAIN SELECTED CELL PHONE BOOSTER SYSTEM | SMALL | 1 | CONT-ACCEPTED | H04B | 2,005 |
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11,040,647 | ACCEPTED | Optical reader station | The invention is directed to an optical reader station for reading an object and a method of controlling an illumination source in the station for illuminating the object. The optical reader station comprises a mount for an optical reader and a stand with a surface for receiving the object; the optical reader includes an imager with an object field of view in which the object to be read is positioned. The station further includes a radiation source positioned within the object field of view and arranged to be obstructed by the object when the object is in position to be read. A detection mechanism, which is positioned to receive radiation from the radiation source when the radiation source is not obstructed by the object, deactivates the illumination source when radiation source radiation is detected. The detector mechanism may form part of an auto-exposure control in the imager, which senses ambient light impinging on the imager including the radiation from the radiation source for controlling the illumination level of the illumination source, or it may be a separate detector, which senses the radiation from the radiation source for deactivating the illumination source. The radiation source, which may be an infrared source, a visible light source, a UV source or a luminescence emitter activated by a UV source, may be mounted within the surface of the stand. | 1. An optical reader station for reading an object comprising: an optical reader having: an imager having an object field of view in which an object is to be positioned to be read; and, a source of illumination for illuminating the object to be read, wherein the intensity of illumination is controlled by the imager in proportion to the level of ambient light on the object; a radiation source positioned within the object field of view and adapted to be obstructed by the object when the object is positioned to be read; and, detector means positioned to receive radiation from the radiation source when the radiation source is not obstructed and adapted to deactivate the illumination source when radiation is detected. 2. An optical reader station as claimed in claim 1 wherein the radiation source comprises an infrared source. 3. An optical reader station as claimed in claim 1 wherein the radiation source comprises a visible light source. 4. An optical reader station as claimed in claim 1 wherein the radiation source comprises a UV source. 5. An optical reader station as claimed in claim 1 wherein the radiation source comprises a luminescence emitter activated by a UV source. 6. An optical reader station as claimed in claim 1 wherein the detector means comprises an auto-exposure control coupled to the imager for detecting the radiation and coupled to the illumination source for controlling the deactivation of the illumination source. 7. An optical reader station as claimed in claim 6 wherein the illumination source is a target source. 8. An optical reader station as claimed in claim 6 wherein the radiation source comprises an infrared source. 9. An optical reader station as claimed in claim 6 wherein the radiation source comprises a visible light source. 10. An optical reader station as claimed in claim 1 wherein the radiation source comprises a UV source. 11. An optical reader station as claimed in claim 1 wherein the radiation source comprises a luminescence emitter activated by a UV source. 12-31. (canceled) 32. In an optical reader for reading an object having an imager and an illumination source for illuminating the object to be read, a method for controlling the illumination source comprising: detecting ambient light impinging on the imager; controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read; and directing constant radiation having a predetermined threshold level at the imager when the object is not in a position to be read. 33. A method as claimed in claim 32 wherein the radiation is selected from infrared, visible, UV and luminescent radiation. 34. In an optical reader for reading an object, said reader having an imager and an illumination source for illuminating the object to be read, a method for controlling the illumination source, said method comprising: detecting ambient light impinging on the imager; controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read; directing radiation to a detector when the object is not in a position to be read; and disabling the illumination source in response to the radiation detected by the detector. 35. A method as claimed in claim 34 wherein the radiation is selected from infrared, visible, UV and luminescent radiation. | FIELD OF THE INVENTION The invention relates generally to optical reader stations and more particularly to unobtrusive optical reader stations, with minimal user interaction, low latency, and low energy use. BACKGROUND OF THE INVENTION Optical reader stations for scanning symbols have applications such as inventory control, parcel tracking, identification and security, i.e. wherever an electronic database may be maintained against a set of tangible elements. In such a station, the symbology reader performs the necessary function of converting the tangible information into electronic information. Scanners in the optical reader stations may be handheld, permanently mounted, or they may consist of handheld scanners with a complementary mount for use in presentation mode scanning. In particular situations such as grocery checkouts or identification queues, a scanner is preferably a fixed mount or in a presentation mode of operation. In general, it is desirable that such stations draw low power, operate under low component stress, are simple and cost-effective to manufacture, are unobtrusive in their deployment, and are retrofitable and make use of existing system resources when improvements are considered. Each symbology reader has imaging and decoding functions. The imaging function acquires an image of a coded object and converts the optical image information to corresponding electronic information. The decoding function extracts the encoded message from the electronic information. The reader may also include other major functions where necessary or advantageous. For example a reader may include the functions of illuminating and/or targeting the symbol to be read. Variable illumination may be required to supply sufficient photonic radiation to capture a suitable image in varying ambient conditions. The required level of illumination on the object may be controlled by an auto-exposure function within the reader. A targeting system aids in positioning the symbol in the field of view. Different strategies have been used during the development of readers. Some reader systems have inactive and active states, wherein they are activated to scan an object in response to an event, such as the pressing of a button, after which they return to their inactive state. The event that activates this type of reader might also be the detection of the absence or presence of a predetermined symbology in the object field by periodically scanning it. The absence of the predetermined symbology may signify that a valid object has been placed in the object field. Other types of readers are always active once they are switched on in that they continuously scan the object field and attempt to decode the imaged information without regard to the presence of a valid symbol within the field. One method for controlling the active/inactive states of a reader is described in U.S. Pat. No. 5,949,052, which issued to Longacre, Jr. et al on Sep. 7, 1999. This disclosure is directed to the use of a special default symbol, the detection of which places the reader in an active state. This device may employ a predetermined pattern of backlighting on the surface where an object is to be placed. The backlighting lights a predetermined symbol from the back, which is scanned periodically and decoded by the reader. When the predetermined symbol is detected, the reader is placed in an inactive mode, when the predetermined symbol is not detected and the reader is placed in an active mode. When the predetermined symbol is not detected, it means that an object to be read is obstructing the line of sight from predetemined symbol to the reader, and the reader is activated to operate in its normal operating mode. Another form that the backlighting technique may take is described in U.S. Pat. No. 6,298,175, which issued to Longacre, Jr. et al on Oct. 2, 2001, wherein the backlighting emits light in a predetermined pattern such as being intermittently on and off, which is recognized by the reader. Although this solution provides benefits such as power saving, a station must be modified to include new apparatus and programming to both generate and recognize the predetermined symbol, or pattern. Another drawback is the latency introduced by this approach arising from the duration of switching to an active state. Increased latency lowers station productivity. Existing continuous scan configurations do not adequately conserve power, and often operate with a constant or pulsed illumination source, which is found to be obtrusively non-ergonomic. In addition, the systems described above are not satisfactory solutions for existing event driven or continuous configurations. They do not provide a sufficiently simple low latency, cost-effective option that minimizes the use of new resources by maximizing the incorporation with existing reader resources, making it retrofittable in a simple manner. Therefore, there is a need for improved unobstusive optical reader stations, with minimal user interaction, low latency and low energy use. SUMMARY OF THE INVENTION The invention is directed to an optical reader station for reading an object. The optical reader station comprises an optical reader having an imager with an object field of view in which an object that is to be read is positioned and a source of illumination for illuminating the object to be read. The station further includes a radiation source positioned within the object field of view and arranged to be obstructed by the object when the object is positioned to be read. A detection mechanism is positioned to receive radiation from the radiation source when the radiation source is not obstructed by the object for deactivating the illumination source. In accordance with another aspect of the invention, the detector mechanism comprises an auto-exposure control coupled to the imager for sensing the radiation and to the illumination source for controlling the deactivation of the illumination source. In accordance with a further aspect of the invention, the optical reader station for reading an object comprises an optical reader having an imager with an object field of view in which an object is to be positioned to be read, a source of illumination for illuminating the object to be read, and an auto-exposure controller coupled to the imager to control the illumination source in response to radiation on the imager. The optical reader station further includes a radiation source positioned within the object field of view to direct radiation towards the imager, wherein the radiation source is arranged to be obstructed by the object when the object is positioned to be read and wherein the illumination source is deactivated when the radiation source is unobstructed by the object and radiation from the radiation source impinges on the imager. With regard to a particular aspect of the invention, the optical reader station further includes a stand for mounting the radiation source and for receiving the object to be read, and a mounting mechanism connected to the stand for receiving the optical reader in a fixed or a detachable manner. In accordance with another aspect of the invention, an optical reader station for reading an object comprises an optical reader mount having a stand with a surface for receiving the object to be read and an optical reader fixed to the mount. The optical reader includes an imager facing the stand, a source of illumination for illuminating the object on the stand, and an auto-exposure control coupled to the imager to control the illumination source in response to radiation on the imager. The optical reader station further includes a radiation source mounted on the stand facing the imager for directing radiation to the imager, whereby the source of illumination is adapted to be deactivated by the auto-exposure control when the imager receives radiation from the radiation source. With regard to a particular aspect of the invention, the optical reader is detachably fixed to the mount. In accordance with a further particular aspect of the invention, the radiation source is mounted within the surface of the stand. In accordance with other aspects of the invention, the radiation source is an infrared source, a visible light source, a UV source or a luminescence emitter activated by a UV source. With regard to another particular aspect of the invention, the illumination source is a target source or includes a target source. In accordance with a further aspect, the invention is directed to a method for controlling an illumination source in an optical reader for reading an object having an imager and an illumination source for illuminating the object to be read. The method comprises detecting ambient light impinging on the imager, controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read, and directing constant radiation having a predetermined threshold level at the imager when the object is not in a position to be read. In accordance with another aspect of the invention, method for controlling an illumination source in an optical reader for reading an object having an imager and an illumination source for illuminating the object to be read, comprises detecting ambient light impinging on the imager, controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read, directing radiation having a predetermined threshold level at a detector when the object is not in a position to be read, and disabling the illumination source in response to the radiation detected by the detector. With regard to a particular aspect of the invention, the directed radiation is infrared, visible, UV or luminescent radiation. Other aspects and advantages of the invention, as well as the structure and operation of various embodiments of the invention, will become apparent to those ordinarily skilled in the art upon review of the following description of the invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described with reference to the accompanying drawings, wherein: FIG. 1 is a schematic diagram of a prior art optical reader station; FIG. 2 is a functional block diagram of a prior art optical reader station; FIG. 3 is a block diagram of the prior art optical reader station; FIG. 4 is a schematic diagram of a portion of a prior art optical reader station using auto-exposure control; FIG. 5 is a schematic diagram of an embodiment of an optical reader station in accordance with the present invention having an infrared radiation source; FIG. 6 is schematic diagram of the optical path of a further embodiment of the optical reader station in accordance with the present invention having a visible light radiation source, FIG. 7 is a schematic diagram of the optical path of another embodiment of the optical reader station in accordance with the present invention having a near UV light radiation source; FIG. 8 is a schematic diagram of the optical path of a further embodiment of the optical reader station in accordance with the present invention having a luminescent radiation source; FIG. 9 is a schematic diagram of the optical path of an embodiment of the optical reader station in accordance with the present invention having a light detector; and FIG. 10 is a block diagram of a optical reader station in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 is a schematic diagram of a basic optical reader station 100. Station 100 includes an optical reader 110 and a mount 120 for receiving the optical reader. The mount 120 further includes a stand 130 on which an object 140 that is to be scanned is placed. The reader 10 may be permanently fixed to the mount 120, or alternatively the reader 110 may be a portable optical reader that attaches to the mount 120 in a temporary fashion. The optical reader 110 faces the stand 130, such that it can scan the object 140 placed on it. Prior art optical readers 110 are capable of carrying out a number of functions when reading an object symbol 140, some of the functions are schematically illustrated in FIG. 2. A reader 110 includes the ability of imaging 210 the object symbol 140 that is placed on the stand 130 in the reader's object field of view and then decoding 220 the symbol 140 from the electronic information provided by the imaging function 210. The reader 110 may also include the functions of targeting 230 the object symbol 140 as well as illuminating 240 the object symbol. 140 so that it can be properly imaged. The illumination 240 function may include an auto-exposure function 250, for controlling the level of illumination depending on the ambient light during the imaging process. Imaging 210 is necessary to acquire an optical image of a coded object symbol 140 and to convert the optical image information to equivalent electronic information. Decoding 220 is necessary to extract the message encoded in the object symbol 140 from the equivalent electronic information. The illumination function 240 supplies sufficient photonic radiation to suitably capture the image of the object symbol 140, particularly through the use of auto-exposure 250, which maintains a desirable level of radiation on the object in varying ambient light conditions. Targeting 230 aids in positioning the object symbol 140 on the stand 130 so that it is within the reader's object field of view. All of the above functions may be utilized whether the optical reader 110 is operated in an event driven mode or in a continuous scan mode. A block diagram of the prior art optical reader 110 is shown in FIG. 3. The optical reader 110 includes a computer system 310, an imager 320, imager optics 325, incident optics 335, and incident radiation sources 330. The incident sources 330 include an illumination source 340 and may include a target source 350. The imager optics 325 focuses an object 140 to be scanned onto the imager 320. The incident optics 335 directs the light from the illumination source 340 onto the object 140 and may also direct a target source 350 marker onto the stand 130 to facilitate the placement of the object 140 in the object field of view for the imager 320. The computer system 310 typically comprises a bus 360, processor 370, a memory 380, and an input/output interface 390. Memory 380 will store the operating programs 400 such as the imaging and decoding operating programs as well as the auto-exposure program 410 if required, and the data 420. The bus 360 interconnects the computer system 310 elements, along with imager 320 and incident sources 330. Note that the prior art also includes systems with independent program and data memories. For purposes of the invention described below, either is compatible. The single memory prior art is selected for illustration, and one skilled in the art will understand the trivial adaptation necessary to employ independant program/data memories. Using the program or programs 400 stored in and retrieved from memory 380, the processor 370 operates the imager 320 and incident sources 330 according to good image acquisition practice, to acquire and decode the images of the object symbols 140, and to store the results in the data memory 420 and/or communicate them externally via the I/O interface 390. In order to obtain satisfactory image acquisition in variable ambient light conditions, an auto-exposure function is highly desirable. In general, auto-exposure may affect exposure time, illumination and gain. Particularly interesting for the present invention, the auto-exposure function involves adjusting the illumination on the object symbol 140 to a suitable level by controlling the amount of light emanating from optical reader illumination source 340 in response to the overall amount of light detected by the imager 320 during a scan. Optical readers 110 of various types may use different measurements to control auto-exposure, for instance the response may be based on the average light detected over the entire imager 320 or over a portion of the imager. Typically the auto-exposure control includes the processor 370, in conjunction with an auto-exposure program 410, the imager 320 and the illumination source 340. In this arrangement the processor 370 responds to a sample or aggregation of the imager 320 output to control the activation of the illumination source 340. The source 340 usually has a range of brightness from a fully ON position to provide a brightness level necessary to scan an object 140 when there is no ambient light, to a fully OFF position when the ambient light is at or above a threshold level where there is sufficient light to scan the object 140. FIG. 4, in a schematic diagram of a portion of the optical reader station 100, shows the radiation directed to the object 140 and reflected from the object 140 to the imager 320. The radiation travels along the path 401 from the illumination source 340 through the incident optics 335 to the surface of the object 140. This radiation is reflected from the object 140 and continues along the path 401 through the imager optics 325 to the imager 320. Depending on the imager optics 325, the optical reader station 100 will have an object field of view, represented by the broken lines X, within which the imager 320 will register an image of the object 140. The area that the imager 320 sees on the surface of the stand 130 is preferably only slightly bigger than the object 140 itself and may be rectangular, circular or any other desired shape as determined by the optics 325. FIG. 5 is a schematic diagram of a portion of an optical reader station 500 in accordance with the present invention. For clarity and to simplify the description, elements in the optical reader station 500 which are similar to those in the optical reader station 100 in FIG. 4 carry the same reference numbers. The portion of the optical reader station 500 shown includes a stand 130 on which may be positioned the object 140 to be read, an imager 320 with its associated optics 325 as well as an illumination source 340 and its associated optics 335. The stand 130 is depicted independently from whatever work surface it may be placed on, but a work surface integrated embodiment is also envisioned. In addition, in accordance with the present invention the optical reader station 500 includes a source of radiation 550 mounted in the stand 130 at the location where an object 140 to be read is to be positioned. The radiation beam from the source 550 is directed to the imager 320 through the imager optics 325 and would preferably be confined to the space defined by broken lines Y, but need not be so. The cross-section of the radiation beam may be circular, rectangular or any other appropriate shape, however it is shaped and positioned such that, when an object 140 is placed at its appropriate position on the stand 130 for scanning, it will obscure the source 550 radiation from the imager 320. In order to direct the user to the field of view, the stand may be marked. The radiation source 550 operates in conjunction with the auto-exposure control in the optical reader station 500 in the following manner. When an object 140 is not present within the object field of view as represented by broken lines X, the imager 320 will receive the radiation from the source 550 and the auto-exposure program will deactivate the illumination source 340. To accomplish this the source 550 must provide sufficient radiation to the imager 325 so that the auto-exposure control will see it as being at or over its threshold of required exposure level. Thus illumination source 340 will remain turned off until radiation source 550 is obstructed. When an object 140 is placed in the object field of view, the object 140 substantially obstructs the radiation source 550 beam defined by broken lines Y and the imager 320 is no longer exposed to the radiation from source 550. This will allow the over-exposure control to operate in the normal manner and set the illumination from the source 340 to a level required to properly image the object 140. In the preferred embodiment of the present invention, the radiation source 550 is a source of infrared light. Typically, imager sensors 320, both CCD and CMOS, respond to infrared light as well as to visible light; the use of infrared light as the source 550 of continuous radiation is particularly advantageous in view of the size and the cost of infrared radiation sources as well as the fact that the infrared light source is much less obtrusive in situations where the level of the ambient light is low. FIGS. 6 and 7 illustrate schematic diagram of a portion of optical reader stations 600 and 700 in accordance with the present invention, which are two alternate embodiments to the optical reader station 500. Again, the elements in the optical reader stations 600 and 700, which are similar to those in the optical reader station 100 in FIG. 4 carry the same reference numbers. Thus the portion of the optical reader stations 600, 700 shown includes a stand 130 on which may be positioned the object 140 to be read, an imager 320 with its associated optics 325 as well as an illumination source 340 and its associated optics 335. In these embodiments of the optical reader stations 600, 700, the sources of radiation 650, 750 are in the visible light range and the near-violet UV range, respectively. Virtually all imagers 325 respond well to a source in the visible light range 650, which, however, is more obtrusive then infrared, while imagers do not respond as well to the near-violet UV source 750 as they do to infrared, the radiation from the UV source 750 is less obtrusive than visible light. In a further embodiment of the present invention illustrated in FIG. 8, which illustrates a schematic diagram of a portion of an optical reader station 800, the elements in the optical reader station 800, which are similar to those in the optical reader station 100 in FIG. 4, carry the same reference numbers. Thus the portion of the optical reader station 800 shown includes a stand 130 on which may be positioned the object 140 to be read, an imager 320 with its associated optics 325 as well as an illumination source 340 and its associated optics 335. In addition, in accordance with the present invention the optical reader station 800 includes a fluorescent or phosphorescent emitter 855 mounted in the stand 130 at the location where an object 140 to be read would be positioned. Emitter 855 is induced to luminesce by a UV source 850 of radiation, which is positioned to direct UV radiation to the emitter 855 as represented by broken lines Z. The luminescent radiation from the emitter 855 is directed to the imager 320 through the imager optics 325 and would preferably be confined to the space defined by broken lines Y, but need not be so. As in the previous embodiments, the luminescent radiation from emitter 855 operates in conjunction with the auto-exposure control in the optical reader station 800 in the following manner. When an object 140 is not present within the object field of view as represented by broken lines X, the imager 320 will receive the radiation from the emitter 855 and the auto-exposure program will deactivate the illumination source 340. Thus illumination source 340 will remain turned off as long a nothing obstructs the emitter 855, and in this embodiment as long as nothing obstructs the UV radiation from source 850 from impinging on the emitter 855, as well. When an object 140 is placed in the object field of view, the object 140 substantially obstructs the emitter 855 radiation directed to the imager 320. This will allow the auto-exposure function to control the illumination from the source 340 to a level required to properly image the object 140. The same will occur if the UV radiation from source 850 is obstructed from impinging on the emitter 855. In the embodiment of the present invention illustrated in FIG. 9, which illustrates a schematic diagram of a portion of an optical reader station 900, the elements in the optical reader station 900, which are similar to those in the optical reader station 100 in FIG. 4, carry the same reference numbers. Thus the portion of the optical reader station 900 shown includes a stand 130 on which may be positioned the object 140 to be read, an imager 320 with its associated optics 325 as well as an illumination source 340 and its associated optics 335. In addition, in accordance with the present invention the optical reader station 900 includes a source of radiation 950 mounted in the stand 130 at the location where an object 140 to be read would be positioned. The radiation source 950 may be the same as any one of the radiation sources 550, 650, 750 described with respect to FIGS. 5, 6 or 7 respectively. However, in the present embodiment, the radiation beam from the source 950 is directed to a sensing detector 955 and would preferably be confined to the space defined by broken lines Y, but need not be so. The cross-section of the radiation beam may be circular, rectangular or any other appropriate shape, however it is shaped and positioned such that, when an object 140 is placed at the appropriate position on the stand 130 for scanning, it will obscure the source 950 radiation from the sensing detector 955. The sensing detector 955 would preferably be located close to the imager 320 in the optical reader station 900. The sensing detector 955 is connected to the bus 360 in the computer system 310 as illustrated in FIG. 10 such that under the control of processor 370, the illumination source 340 is turned OFF and will remain in that state as long a nothing obstructs the radiation source 950. When an object 140 is placed in the object field of view, the object 140 substantially obstructs the radiation source 950 beam and sensing detector 955 is no longer exposed to the radiation from source 950. This will cause the processor to reactivate the illumination source 340 and will allow the auto-exposure to control the illumination from the source 340 to a level required to properly image the object 140. Modifications in accordance with the present invention made to the optical reader 110 illustrated in FIG. 3, are shown in the optical reader 1010 illustrated in FIG. 10. For clarity and to simplify the description, elements in the optical reader 1010 which are similar to those in the optical reader station 110 in FIG. 3 carry the same reference numbers. The optical reader 1010 includes a computer system 310, an imager 320, imager optics 325, incident optics 335, and incident radiation sources 330. The incident sources 330 include an illumination source 340 and may include a target source 350. The computer system 310 typically comprises a bus 360, processor 370, a memory 380, and an input/output interface 390. In accordance with the present invention, the optical reader 1010 may include a radiation source 550, 650, 750, 850 or 950 of the type described with regard to FIG. 5 to 9 respectively, which is connected to the bus 360 in order to be activated when the optical reader 1010 is turned on. For the embodiment described with respect to FIG. 9, the sensing detector 955 is also connected to the bus 360 such that the processor 370, using the illumination source program 960, will turn the illumination source 340 OFF or ON depending on whether the sensing detector 955 does or does not receive radiation from the radiation source 950 respectively. In addition, as seen on FIG. 10, both the illumination source 340 and the target source 350 are connected to the bus 360 and are controlled by the processor 370. In view of this, the target source 350 may also be controlled to be turned OFF at the same time as illumination source 340 in response to the sensing detector 955. Conventionally, the illumination source 340 is designed to provide sufficient radiation to properly illuminate the object 140. On the other hand target source 350 is designed to provide a relatively weak marker to assist in the placement of the object 140. Power consumption may further be minimized by combining the illumination and the target functions into one incident source 330 calibrated to a level marginally more than sufficient to illuminate an object placed on the stand 130 for optical reading. In this way the incident source 330 will operate as a target marker, in such a manner that it can be varied in intensity from a predetermined minimum, a level at which it is still visible in bright ambient light, to a predetermined maximum intensity, a level at which it illuminates the object properly when no ambient light is present. In a further embodiment of the invention, the mount 120, shown in FIG. 1, may include a detector 960 located within it in order to detect the physical presence of the optical reader 110, 1010 when attached to the mount 120. When the portable optical reader 110, 1010 is attached to the mount 120, detector 960, which is coupled to the bus 360, provides a signal to the processor 370 to over-ride other illumination programs in order to deactivate the illumination source 340 and to activate the target source 350. In this particular embodiment, the target source 350 would be calibrated in the same manner as the incident source 330 described above, to a level marginally more than sufficient to illuminate an object 140 placed on the stand 130 of the fixed mount 120 for optical reading. From the above embodiments, it is seen that the present invention is particularly advantageous since virtually no modifications other then some programming are required to the computer system 310, and existing functions of the optical reader are partially used to implement the invention. In addition only relatively inexpensive physical modifications such as the installation of a radiation source are required on the optical reader stations in order to implement the invention. At the same time, many advantages are reaped by minimizing the power consumption of the station, lowering component stress by shortening the operating time of certain components and by limiting the cycling rate of others, and by providing a more aesthetically acceptable station by reducing its obtrusive effects. While the invention has been described according to what is presently considered to be the most practical and preferred embodiments, it must be understood that the invention is not limited to the disclosed embodiments. Those ordinarily skilled in the art will understand that various modifications and equivalent structures and functions may be made without departing from the spirit and scope of the invention as defined in the claims. Therefore, the invention as defined in the claims must be accorded the broadest possible interpretation so as to encompass all such modifications and equivalent structures and functions. | <SOH> BACKGROUND OF THE INVENTION <EOH>Optical reader stations for scanning symbols have applications such as inventory control, parcel tracking, identification and security, i.e. wherever an electronic database may be maintained against a set of tangible elements. In such a station, the symbology reader performs the necessary function of converting the tangible information into electronic information. Scanners in the optical reader stations may be handheld, permanently mounted, or they may consist of handheld scanners with a complementary mount for use in presentation mode scanning. In particular situations such as grocery checkouts or identification queues, a scanner is preferably a fixed mount or in a presentation mode of operation. In general, it is desirable that such stations draw low power, operate under low component stress, are simple and cost-effective to manufacture, are unobtrusive in their deployment, and are retrofitable and make use of existing system resources when improvements are considered. Each symbology reader has imaging and decoding functions. The imaging function acquires an image of a coded object and converts the optical image information to corresponding electronic information. The decoding function extracts the encoded message from the electronic information. The reader may also include other major functions where necessary or advantageous. For example a reader may include the functions of illuminating and/or targeting the symbol to be read. Variable illumination may be required to supply sufficient photonic radiation to capture a suitable image in varying ambient conditions. The required level of illumination on the object may be controlled by an auto-exposure function within the reader. A targeting system aids in positioning the symbol in the field of view. Different strategies have been used during the development of readers. Some reader systems have inactive and active states, wherein they are activated to scan an object in response to an event, such as the pressing of a button, after which they return to their inactive state. The event that activates this type of reader might also be the detection of the absence or presence of a predetermined symbology in the object field by periodically scanning it. The absence of the predetermined symbology may signify that a valid object has been placed in the object field. Other types of readers are always active once they are switched on in that they continuously scan the object field and attempt to decode the imaged information without regard to the presence of a valid symbol within the field. One method for controlling the active/inactive states of a reader is described in U.S. Pat. No. 5,949,052, which issued to Longacre, Jr. et al on Sep. 7, 1999. This disclosure is directed to the use of a special default symbol, the detection of which places the reader in an active state. This device may employ a predetermined pattern of backlighting on the surface where an object is to be placed. The backlighting lights a predetermined symbol from the back, which is scanned periodically and decoded by the reader. When the predetermined symbol is detected, the reader is placed in an inactive mode, when the predetermined symbol is not detected and the reader is placed in an active mode. When the predetermined symbol is not detected, it means that an object to be read is obstructing the line of sight from predetemined symbol to the reader, and the reader is activated to operate in its normal operating mode. Another form that the backlighting technique may take is described in U.S. Pat. No. 6,298,175, which issued to Longacre, Jr. et al on Oct. 2, 2001, wherein the backlighting emits light in a predetermined pattern such as being intermittently on and off, which is recognized by the reader. Although this solution provides benefits such as power saving, a station must be modified to include new apparatus and programming to both generate and recognize the predetermined symbol, or pattern. Another drawback is the latency introduced by this approach arising from the duration of switching to an active state. Increased latency lowers station productivity. Existing continuous scan configurations do not adequately conserve power, and often operate with a constant or pulsed illumination source, which is found to be obtrusively non-ergonomic. In addition, the systems described above are not satisfactory solutions for existing event driven or continuous configurations. They do not provide a sufficiently simple low latency, cost-effective option that minimizes the use of new resources by maximizing the incorporation with existing reader resources, making it retrofittable in a simple manner. Therefore, there is a need for improved unobstusive optical reader stations, with minimal user interaction, low latency and low energy use. | <SOH> SUMMARY OF THE INVENTION <EOH>The invention is directed to an optical reader station for reading an object. The optical reader station comprises an optical reader having an imager with an object field of view in which an object that is to be read is positioned and a source of illumination for illuminating the object to be read. The station further includes a radiation source positioned within the object field of view and arranged to be obstructed by the object when the object is positioned to be read. A detection mechanism is positioned to receive radiation from the radiation source when the radiation source is not obstructed by the object for deactivating the illumination source. In accordance with another aspect of the invention, the detector mechanism comprises an auto-exposure control coupled to the imager for sensing the radiation and to the illumination source for controlling the deactivation of the illumination source. In accordance with a further aspect of the invention, the optical reader station for reading an object comprises an optical reader having an imager with an object field of view in which an object is to be positioned to be read, a source of illumination for illuminating the object to be read, and an auto-exposure controller coupled to the imager to control the illumination source in response to radiation on the imager. The optical reader station further includes a radiation source positioned within the object field of view to direct radiation towards the imager, wherein the radiation source is arranged to be obstructed by the object when the object is positioned to be read and wherein the illumination source is deactivated when the radiation source is unobstructed by the object and radiation from the radiation source impinges on the imager. With regard to a particular aspect of the invention, the optical reader station further includes a stand for mounting the radiation source and for receiving the object to be read, and a mounting mechanism connected to the stand for receiving the optical reader in a fixed or a detachable manner. In accordance with another aspect of the invention, an optical reader station for reading an object comprises an optical reader mount having a stand with a surface for receiving the object to be read and an optical reader fixed to the mount. The optical reader includes an imager facing the stand, a source of illumination for illuminating the object on the stand, and an auto-exposure control coupled to the imager to control the illumination source in response to radiation on the imager. The optical reader station further includes a radiation source mounted on the stand facing the imager for directing radiation to the imager, whereby the source of illumination is adapted to be deactivated by the auto-exposure control when the imager receives radiation from the radiation source. With regard to a particular aspect of the invention, the optical reader is detachably fixed to the mount. In accordance with a further particular aspect of the invention, the radiation source is mounted within the surface of the stand. In accordance with other aspects of the invention, the radiation source is an infrared source, a visible light source, a UV source or a luminescence emitter activated by a UV source. With regard to another particular aspect of the invention, the illumination source is a target source or includes a target source. In accordance with a further aspect, the invention is directed to a method for controlling an illumination source in an optical reader for reading an object having an imager and an illumination source for illuminating the object to be read. The method comprises detecting ambient light impinging on the imager, controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read, and directing constant radiation having a predetermined threshold level at the imager when the object is not in a position to be read. In accordance with another aspect of the invention, method for controlling an illumination source in an optical reader for reading an object having an imager and an illumination source for illuminating the object to be read, comprises detecting ambient light impinging on the imager, controlling the intensity of the illumination source in proportion to the level of ambient light detected by the imager when the object is in a position to be read, directing radiation having a predetermined threshold level at a detector when the object is not in a position to be read, and disabling the illumination source in response to the radiation detected by the detector. With regard to a particular aspect of the invention, the directed radiation is infrared, visible, UV or luminescent radiation. Other aspects and advantages of the invention, as well as the structure and operation of various embodiments of the invention, will become apparent to those ordinarily skilled in the art upon review of the following description of the invention in conjunction with the accompanying drawings. | 20050121 | 20070807 | 20050616 | 66771.0 | 0 | LABAZE, EDWYN | OPTICAL READER STATION | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,040,666 | ACCEPTED | Hybrid electro-mechanical transmission park system and method of assembly | This invention relates to the housing of a hybrid electro-mechanical transmission consisting of park pawl system located in the end cover portion of the transmission housing. The end cover portion is configured to cover the park pawl system and allow access to the components of the park pawl system for assembly or service even as the end cover portion remains attached to the main housing of the transmission. Beyond providing coverage to the park pawl system, the end cover portion also provides structural support to a main housing portion during operation of the transmission. A method of assembling a park pawl system between main and end cover portions of a transmission housing is also provided. | 1. A transmission including a transmission housing, comprising: a main housing portion of the transmission housing; an actuable park pawl system; and an end cover portion of the transmission housing; wherein said park pawl system is at least partially located in said end cover portion of the transmission housing. 2. The transmission housing of claim 1, wherein said park pawl system includes a pawl, a pawl return spring, and actuator guide assembled with said end cover portion. 3. The transmission housing of claim 2, wherein said end cover portion of the transmission housing is detachable from said main housing. 4. The transmission housing of claim 3, wherein said end cover portion of the transmission housing is configured to define a sufficient cavity therein to allow access to said park pawl system without detachment of said end cover portion of the transmission housing from said main housing. 5. The transmission housing of claim 2, further comprising within said main housing portion of the transmission housing: a shift selector which is operative to actuate said park pawl system; a connecting rod operative to send a mechanical signal from said shift selector to said park pawl system; wherein said connecting rod is located at least partially in said main housing portion and at least partially in said end cover portion of the transmission housing; and wherein said end cover portion of the transmission housing is 10 further configured to define an aperture through which said connecting rod may pass from said main housing portion to said actuator guide assembled with said end cover portion of the transmission housing. 6. The transmission housing of claim 3, including: a pawl pin for said pawl in said end cover portion of the transmission housing; and wherein said end cover portion of said transmission housing has an aperture configured to enable the installation of said pawl pin when said end cover portion of the transmission housing is attached to said main housing. 7. The transmission housing of claim 2, including an output shaft, wherein said end cover portion of said transmission housing is mechanically sufficiently strong to support loading from said output shaft of said transmission when said park pawl system is actuated. 8. The transmission housing of claim 7, wherein said end cover portion of the transmission housing is die cast. 9. The transmission housing of claim 8, wherein said end cover portion of the transmission housing is comprised of an aluminum alloy, which in addition to being sufficiently strong, is significantly lighter in weight than a ferrous alloy. 10. The transmission housing of claim 9, wherein said end cover portion of the transmission housing is sufficiently compact to define a space adjacent the exterior of the transmission housing to enable other vehicle components to nest adjacent the exterior of the transmission housing. 11. The transmission housing of claim 3, wherein said park pawl system in said end cover portion of the transmission housing includes: a pawl engagement gear; wherein said park pawl system is operative to resist a vehicle's tendency to roll down a sloped surface through engagement of said pawl with said pawl engagement gear; an output shaft fixed with respect to said pawl engagement gear and rotatable therewith in the transmission housing; a first electric motor located in said main housing portion and operative to selectively turn said output shaft; a second electric motor located in said main housing portion and operative to selectively turn said output shaft; and wherein said an end cover portion of the transmission housing is configured sufficiently large to allow at least said second electric motor to be assembled into said main housing portion when said end cover portion is detached from said main housing portion. 12. A transmission, comprising: a main housing portion which at least partially encases the contents of the transmission; a pawl engagement gear; an output shaft fixed with respect to said pawl engagement gear and rotatable therewith; a first electric motor located in said main housing portion and operative to selectively turn said output shaft; a second electric motor located in said main housing portion and also operative to selectively turn said output shaft; an end cover portion attachable to said main housing portion and configured sufficiently large to allow at least said second electric motor to be assembled into said main housing portion; a park pawl system engageable with said pawl engagement gear and at least partially located in said end cover portion of the transmission; wherein said park pawl system includes a pawl, actuator, and actuator guide; and wherein said end cover portion of the transmission is configured to define a sufficient cavity therein to allow access to said park pawl system without detachment of said end cover portion from said main housing. 13. A transmission having a transmission housing, including a main housing portion and an end cover portion, comprising: a pawl engagement gear in one of said housing portions; a park pawl system in said end cover portion engageable with said pawl engagement gear; an output shaft rotatable with said pawl engagement gear; a first electric motor located in said main housing portion and operative to selectively rotate said output shaft; a second electric motor located in said main housing portion and operative to selectively rotate said output shaft; a shift selector in said main housing portion; and wherein said park pawl system in said end cover portion is linked to said shift selector in said main housing portion. 14. The transmission of claim 13, wherein said shift selector is a mechanical unit; operative to actuate said park pawl system; and wherein said mechanical unit includes a connecting rod operative to send a mechanical signal from said shift selector to said park pawl system; wherein said connecting rod passes at least partially through said main housing portion to said end cover portion of the transmission housing. 15. A method of assembling a hybrid electromechanical vehicular transmission having an electric motor module and a park pawl engagement systems comprising: providing a transmission main housing with a terminal portion sufficiently open-ended to receive and house said electric motor module and a first portion of said park pawl engagement system; providing a transmission end cover sufficiently expansive for covering the open-end of said terminal portion and sufficiently configured to house a second portion of said park pawl engagement system; assembling said first portion of said park pawl engagement system in said transmission main housing; assembling said second portion of said park pawl engagement system in said transmission end cover; and mechanically inter-connecting said first and second portions of said park pawl engagement system during the covering of the open-end of said terminal portion by said transmission end cover. 16. The method of claim 15, wherein said first portion of said park pawl engagement system includes a connecting rod, an actuator, and an actuator return spring; and wherein said connecting rod mechanically interconnects said first and second portions of said park pawl engagement system. 17. The method of claim 16, wherein said second portion of said park pawl engagement system includes a pawl engagement gear, a pawl, a pawl return spring, and an actuator guide; and wherein said actuator and said actuator spring are assembled on said connecting rod and said actuator is funneled into said actuator guide during the covering of the open-end of said terminal portion of said main housing by said transmission end cover. 18. The method of claim 15, wherein said first mentioned electric motor module is assembled in said terminal portion adjacent to the open-end thereof; and wherein said first portion of said park pawl system further includes a shift selector housed in said transmission main housing on the opposite side of said electric motor module from the open-end of said terminal portion of said main housing; and wherein said shift selector is assembled to provide mechanical input to the mechanical inter-connection of said first and second portions of said park pawl engagement system. 19. The method of claim 18, wherein the main housing portion of the hybrid electromechanical vehicular transmission is provided to receive and house a second electric motor module which is assembled therein; and wherein said shift selector is placed between the first and second electric motor modules in the main housing portion. | CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application 60/555,141 filed Mar. 22, 2004. TECHNICAL FIELD This invention relates to a hybrid electromechanical transmission having a park pawl system, which is at least partially located and assembled in an end cover portion of a transmission housing. BACKGROUND OF THE INVENTION Vehicle transmissions, specifically planetary gear automatic power transmissions, typically have a park brake mechanism to resist the vehicle's natural tendency to roll down a sloped surface when the vehicle is in park. The contents of such a park brake generally include some sort of gear that is fixed with respect to the output shaft of the transmission and a pawl designed to selectively engage with the gear when the park brake is activated. The pawl substantially prevents the output shaft and attached gear from rotating when the pawl engages with the recesses between the gear teeth. One example of a successful park pawl arrangement is described in commonly assigned U.S. Pat. No. 5,630,339 entitled “Park Mechanism for Vehicle Transmission,” Tuday, T May 20, 1997, and hereby incorporated by reference in its entirety. Vehicles with complex non-traditional powertrains, like electromechanical vehicles, still require a park brake mechanism. However, the alteration of some components of the transmission may require the park pawl and its complementary components to be altered as well. For example, some hybrid electromechanical transmissions require the use of two electric motors to supply power to the output shaft of the transmission. The two motors significantly increase the amount of packaging space needed for the transmission. Therefore, the surrounding transmission components, including the park brake mechanism, must be adjusted to accommodate the additional power supply. The location and placement of these surrounding components, however, is limited by the dimensions of neighboring vehicle components and by any clearance requirements for the underbody of the vehicle. The park pawl for the aforementioned transmission was placed farther rearward to accommodate the second electric motor. A cover or housing was required to protect the park brake from contamination. Major design considerations of the rear cover include manufacturability, structural integrity, weight, and material costs requirements. SUMMARY OF THE INVENTION In light of the design challenges mentioned, the present invention provides a transmission housing with a park pawl system located in an end cover portion of the transmission housing. The end cover portion blankets the park pawl system while also defining a cavity that is large enough to provide access to the park pawl system through the exterior of the end cover portion. In one aspect of the present invention, the end cover portion is detachable from the main housing of the transmission. However, the park pawl system remains accessible without detaching the end cover portion from the main housing. In another aspect of the present invention, a shift selector located in the main housing of the transmission is mechanically linked to the park pawl system in the end cover portion of the transmission. The end cover portion has an aperture through which a connecting rod extends between the shift selector and park pawl system. In another aspect of the present invention, an aperture is included in the end cover portion to allow for the installation of a pawl pin onto the pawl without detaching the end cover portion from the main housing of the transmission. In an additional aspect of the present invention, the end cover portion is designed to be sufficiently strong enough to provide structural support to the main housing of the transmission during operation. More specifically, the present invention relates to a transmission including a transmission housing, with a main housing which defines a portion of the transmission housing and a park pawl system which is at least partially located in an end cover portion of the transmission housing. Another aspect of this invention is a method of assembling a hybrid electro-mechanical vehicular transmission having an electric motor module and a park pawl engagement system. The method includes providing a transmission main housing with a terminal portion sufficiently open-ended to receive and house the electric motor module and a first portion of the park pawl engagement system; providing a transmission end cover sufficiently expansive for covering the open-end of the terminal portion and sufficiently configured to house a second portion of the park pawl engagement system; assembling the first portion of the park pawl engagement system in the transmission main housing; assembling the second portion of the park pawl engagement system in the transmission end cover; and mechanically interconnecting the first and second portions of the park pawl engagement system during the covering of the open-end of the terminal portion by the transmission end cover. The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of an electromechanical transmission housing with end cover portion and with parts broken away to show the electrical motors in their respective housings; FIG. 2 is a perspective view of the engagement gear, park pawl system, connecting rod, and shift selector isolated from the main transmission housing and end cover portion; and FIG. 3 is an exploded perspective view of the end cover portion, engagement gear, park pawl system, and access cover. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, FIGS. 1 through 3, wherein like characters represent the same or corresponding parts throughout the several views, there is shown in FIG. 1 a schematic side elevational view of a hybrid electromechanical transmission 10. The transmission consists of a two-part housing: the main housing 12 and the end cover portion 14. The main housing 12 contains two electric motors (A and B), which have their respective housings (or modules) 16 and 18. Motors A and B are journaled onto the main shaft 20 of the transmission, which is selectively linked to the output shaft 22 of the transmission. The motors (A, B) operate to selectively engage with clutches (not shown) to rotate the main shaft 20 at variable speeds and indirectly rotate the output shaft 22. The available packaging space in the main housing 12 of the transmission 10 is dominated by the drum housings (16 and 18) for the electric motors A and B, respectively (as shown in FIG. 1). One technical advantage of the present invention is that it enables the main housing 12 to accommodate both electric motors (A and B) by rearranging the position of other transmission components, namely the park pawl system 28. Located between and encircled by the pair of motors is a shift selector 24 that is connected (either mechanically or electrically) to the transmission gear shifter (not shown) and to a mechanical link (or connecting rod 26) that controls the park pawl system 28. The park pawl system 28 is encased by the end cover portion 14 of the transmission housing and functions to selectively interact with an engagement gear 30, which is secured to rotate with the output shaft 22. The end cover portion 14 defines a cavity 31, which provides sufficient access to the park pawl system 28 and its components for assembly and servicing without detaching the end cover portion 14 from the main housing 12. FIG. 2 details the interaction between the engagement gear 30, park pawl system 28 and the shift selector 24. The engagement gear 30 has a number of teeth 32 and tooth recesses 34 on its perimeter. On the inner diameter of the engagement gear 30 are a series of complementary splines 36 functioning to secure the engagement gear 30 directly onto the clutch housing 72 (as shown in FIG. 3) and indirectly onto the output shaft 22 (shown in FIG. 1). When the wheels of the vehicle rotate by external forces, such as gravity, the drive shaft also turns and causes the output shaft 22 and engagement gear 30 on the clutch housing 72 to rotate as the engagement gear 30 is configured to rotate with the output shaft 22. With reference to FIG. 2, the park pawl system 28 consists of a pawl pin 38, torsion spring (or pawl return spring 40), pawl 42 and actuator guide 46. The pawl 42, actuator 48, and actuator guide 46 are placed in the end cover portion 14, situated to axially align the pawl 42 with the pawl engagement gear 30. The pawl 42 is configured to fit in the tooth recesses 34 on the engagement gear 30 perimeter upon activation of the park pawl system 28 (as shown at 35). The pawl 42 is mounted on the pawl pin 38, and is free to rotate or pivot about the pawl pin 38. A pawl return spring 40 operates to hold the pawl 42 in the disengaged position except when mechanically engaged. The pawl 42 is mounted adjacent to a slotted actuator guide 46 and actuator 48 so that upon transverse motion of the actuator 48 the pawl 42 is rotated or pivoted between the engaged and disengaged positions. The actuator guide 46 encases the actuator 48 and is secured by a pin 76 (through aperture 77 shown in FIG. 3) with respect to the end cover portion 14. The end cover portion 14 is hollowed at pocket 75 to receive and accommodate the end shape of the actuator guide 46. The actuator guide 46 has an inner cavity 54 contoured to the shape of the actuator 48 (as shown in FIG. 2). The actuator guide 46 has a slot 50 on its perimeter, adjacent the back 43 of the pawl 42, which is configured to guide and support the pivotal movement of the pawl 42. Movement of the actuator 48 aft causes the cam portion 49 and wide portion 52 of the actuator to collide with the back 43 of the pawl and force the park pawl 42 to rotate or pivot into engagement with a recess 34 in the engagement gear 30. Movement of the actuator 48 forward with respect to the pawl 42 moves the cam portion 49 away from the back 43 of the pawl 42 to remove the force of the cam, whereby to release the pawl 42 from the tooth recess 34. When the pawl 42 is released from the tooth recesses 34, the pawl return spring 40 rotates the pawl 42 into the disengaged position allowing the engagement gear 30 to freely rotate. The actuator 48 is spring mounted to an end portion 27 of the connecting rod 26. The axially positioned linear spring (or actuator return spring 58) functions to enable shift selection of park regardless of the position of pawl 42 relative to the engagement gear 30, teeth 32 and tooth recesses 34. If an engagement gear tooth 32 is located over or adjacent to the pawl 42 when park is selected, the pawl will not engage in a recess 34, but the end 27 of the connecting rod will continue to move with respect to the actuator 48 against the bias of spring 58, and the end 27 of the connecting rod will extend slightly beyond the end 55 of the actuator. The actuator return spring 58 enables selection of park by maintaining an axial force or bias on the actuator 48 until the engagement gear 30 rotates to a point where the gear tooth 32 is no longer adjacent to the pawl 42. With the continued bias of actuator return spring 58, the pawl 42 will then engage with a tooth recess 34 at the first opportunity (usually when the vehicle starts or continues to roll). The end 27 of the connecting rod 26, which functions as a mechanical link between the shift selector 24 and the actuator 48 then moves again with respect to the actuator 48 as the pawl 42 engages the tooth recess 34. With reference to FIGS. 1 and 2, the connecting rod 26 is secured to the detent lever 60 of the shift selector at 61. The detent lever 60 is pivotably secured with respect to the main housing 12 of the transmission at 62, where the selector shaft lever (not shown) is also connected. The perimeter of the detent lever 60 has detents 64 on its lower end. The detents 64 are configured to engage with the cylindrical end 66 of a detent retention spring 68. The detent retention spring 68 is indirectly mounted with respect to the main housing 12 of the transmission so that upon placing the vehicle in park the selector shaft lever rotates the detent lever 60 and the cylindrical end 66 of the detent retention spring 68 engages with the most aft detent 70 of the detent lever 60 to secure it in place. To reach this position the detent lever 60 rotates clockwise, or rearward with respect to the main housing 12 moving the connecting rod 26 rearward or toward the end cover portion 14 of the transmission housing 10. Though this is the configuration of the park pawl system 28 in the preferred embodiment, the invention is also compatible with a variety of park systems such as the one described in U.S. Pat. No. 5,685,406 entitled “Park Brake Actuating Mechanism For A Power Transmission,” Crum, et al., Nov. 11, 1997, assigned to General Motors Corporation and hereby incorporated by reference in its entirety. The end cover portion 14 of the transmission housing, as shown in FIG. 3, is designed to encase the engagement gear 30 and park pawl system (38, 40, 42, 46 and 50). The end cover portion 14 is hollowed large enough at 31 to encase the engagement gear 30 and allow it to freely rotate. Splined to the engagement gear 30 is a clutch housing 72, which is also drivably connected to the output shaft 22 (only shown in FIG. 1) of the transmission. The end cover portion 14 contains an aperture 15 to allow for the output shaft 22 to extend out of the end cover portion 14 of the transmission housing. The end cover portion 14, as shown in FIG. 3, defines a cylindrical cavity 31 configured at one side to encircle and support the actuator guide 46 respectively at a pocket 75 and a formed cavity portion 74. The actuator guide 46 is secured to the end cover portion 14 by a pin 76 that runs through the end cover portion 14 at 78 and actuator guide 46 at 77. The end cover portion 14 allows for the connecting rod 26 of the shift selector 24 (both shown in FIG. 2) to pass from the main housing 12 of the transmission to the actuator 48 in the actuator guide 46 in the end cover 14 without interference. In addition to housing the park pawl system 28 and its components, the end cover portion 14 also defines several orifices (80, 82), which provide access to the park pawl system from the outside of the transmission. The first orifice 80 defines an access opening for assembly and service of the park pawl system 28. Orifice 82 provides an entry point for the pawl pin 38 to be assembled to the pawl 42 on the end cover portion 14. The end cover portion 14 further contains a compression gasket 84 to seal the end cover portion 14 as well as a detachable access cover 86 to close the end cover portion 14 of the transmission. The compression gasket 84 and access cover 86 are attached to the end cover portion 14 by a series of structural connectors (or bolts) 88. The end cover portion 14 is attachable to the main housing 12 by similar structural connectors such as 88 at mating orifices such as 90. In sum, the connecting rod 26 between the shift selector 24 and the park pawl engagement system 28 passes through cast openings 94 in the transmission housing 12 and rear cover 14. The connecting rod 26, actuator 48, and actuator return spring 58 are assembled with the transmission main housing 12. The pawl engagement gear 30, pawl 42, pawl return spring 40, and actuator guide 46 are assembled with the transmission rear cover 14. The actuator 48, actuator return spring 58, and connecting rod 26 are passed thru the transmission main housing 12 and rear cover cast windows or configurations 74, and funneled into the actuator guide 46 during final assembly of the transmission 10. The end cover portion 14 also provides structural support to the main housing 12 of the transmission 10 (shown in FIG. 1). The main housing 12 and end portion 14 see torsional loading from the repetitive revolutions of the electric motors (A and B), engine (not shown), clutches (not shown), and output shaft 22. The end cover portion 14 is configured to withstand the torsional loads, driveline loads, clutch piston loads, and park pawl loads of a 7800 lb. vehicle. To provide this support the end cover portion 14 is designed to be a uniform structure, as better seen in FIG. 3, and comprised of an enhanced aluminum alloy die casting Grade ANSI A380.0 or Grade ANSI 383.0. The uniform structure of the end cover portion 14 and use of this alloy provides the necessary structural support while also reducing the weight and material costs of the transmission. In addition to structural support and reinforcements, the end cover portion 14 is designed to comply with packaging constraints and simplify assembly requirements. Primarily, the assembled transmission housing 10 must be compact enough on the inside to contain the park pawl system 28 without impinging upon neighboring vehicle components 98 while still providing the necessary underbody clearance for the vehicle. Additionally, various components located in the main housing 12 of the transmission 10 are accessible from both or either ends 94 or 96 of the main housing 12. Namely, electric motor B, as shown in FIG. 1, should fit through the opening or orifice between the main housing 12 and the end cover portion 14 at 94 before the end cover portion 14 of the transmission is attached to the main housing 12; and electric motor A, as shown in FIG. 1, should fit through the orifice or opening of the main housing 12 at 96. The main housing 12 and end cover portion 14 may be designed to provide various other points of entry into the transmission to simplify the assembly of the components located in the main housing 12, including a main housing 12 which can be accessed through either side of the main housing. Though the end cover portion 14 may be manufactured through a number of processes, in the preferred embodiment the end cover portion 14 is manufactured by die-casting. Generally die-casting is compatible with the use of aluminum alloys. Additionally, die-casting generally also provides excellent dimensional accuracy and stability involving high volumes. The end cover portion 14 has a complex geometry, as shown in FIG. 3, wherein die-casting configures contours to facilitate the park pawl system 28 and its complimentary components—shown in FIG. 2—while remaining compact enough to meet the aforementioned compact packaging requirements. The die (not shown) for the end cover portion 14 is designed with configurations to provide such contoured surfaces. While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Vehicle transmissions, specifically planetary gear automatic power transmissions, typically have a park brake mechanism to resist the vehicle's natural tendency to roll down a sloped surface when the vehicle is in park. The contents of such a park brake generally include some sort of gear that is fixed with respect to the output shaft of the transmission and a pawl designed to selectively engage with the gear when the park brake is activated. The pawl substantially prevents the output shaft and attached gear from rotating when the pawl engages with the recesses between the gear teeth. One example of a successful park pawl arrangement is described in commonly assigned U.S. Pat. No. 5,630,339 entitled “Park Mechanism for Vehicle Transmission,” Tuday, T May 20, 1997, and hereby incorporated by reference in its entirety. Vehicles with complex non-traditional powertrains, like electromechanical vehicles, still require a park brake mechanism. However, the alteration of some components of the transmission may require the park pawl and its complementary components to be altered as well. For example, some hybrid electromechanical transmissions require the use of two electric motors to supply power to the output shaft of the transmission. The two motors significantly increase the amount of packaging space needed for the transmission. Therefore, the surrounding transmission components, including the park brake mechanism, must be adjusted to accommodate the additional power supply. The location and placement of these surrounding components, however, is limited by the dimensions of neighboring vehicle components and by any clearance requirements for the underbody of the vehicle. The park pawl for the aforementioned transmission was placed farther rearward to accommodate the second electric motor. A cover or housing was required to protect the park brake from contamination. Major design considerations of the rear cover include manufacturability, structural integrity, weight, and material costs requirements. | <SOH> SUMMARY OF THE INVENTION <EOH>In light of the design challenges mentioned, the present invention provides a transmission housing with a park pawl system located in an end cover portion of the transmission housing. The end cover portion blankets the park pawl system while also defining a cavity that is large enough to provide access to the park pawl system through the exterior of the end cover portion. In one aspect of the present invention, the end cover portion is detachable from the main housing of the transmission. However, the park pawl system remains accessible without detaching the end cover portion from the main housing. In another aspect of the present invention, a shift selector located in the main housing of the transmission is mechanically linked to the park pawl system in the end cover portion of the transmission. The end cover portion has an aperture through which a connecting rod extends between the shift selector and park pawl system. In another aspect of the present invention, an aperture is included in the end cover portion to allow for the installation of a pawl pin onto the pawl without detaching the end cover portion from the main housing of the transmission. In an additional aspect of the present invention, the end cover portion is designed to be sufficiently strong enough to provide structural support to the main housing of the transmission during operation. More specifically, the present invention relates to a transmission including a transmission housing, with a main housing which defines a portion of the transmission housing and a park pawl system which is at least partially located in an end cover portion of the transmission housing. Another aspect of this invention is a method of assembling a hybrid electro-mechanical vehicular transmission having an electric motor module and a park pawl engagement system. The method includes providing a transmission main housing with a terminal portion sufficiently open-ended to receive and house the electric motor module and a first portion of the park pawl engagement system; providing a transmission end cover sufficiently expansive for covering the open-end of the terminal portion and sufficiently configured to house a second portion of the park pawl engagement system; assembling the first portion of the park pawl engagement system in the transmission main housing; assembling the second portion of the park pawl engagement system in the transmission end cover; and mechanically interconnecting the first and second portions of the park pawl engagement system during the covering of the open-end of the terminal portion by the transmission end cover. The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. | 20050121 | 20090224 | 20050922 | 69971.0 | 0 | LORENCE, RICHARD M | HYBRID ELECTRO-MECHANICAL TRANSMISSION PARK SYSTEM AND METHOD OF ASSEMBLY | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,040,671 | ACCEPTED | Vortex tube cooler | The invention provides an apparatus for moving thermal energy with respect to at least one of a beverage and a food product positioned in a vehicle or a stationary beverage machine. The apparatus includes a vortex tube positionable in a vehicle or a stationary beverage machine. The vortex tube includes an inlet and a cold outlet and a hot outlet. The vortex tube divides a primary air stream received in the inlet into a cold air sub-stream exiting the cold outlet and an a hot air sub-stream exiting the hot outlet. The apparatus also includes a containing member having a first wall with an inner surface for receiving a product. The containing member also includes a second wall surrounding the first wall to define a first cavity. The apparatus also includes a first fluid line extending between the first cavity and one of the cold and hot outlets for communicating one of the cold and hot air sub-streams to the first cavity. The apparatus also includes a third wall disposed between the first and second walls for dividing the first cavity into outer sub-cavity for receiving the air sub-stream and an inner sub-cavity for receiving a thermal fluid. | 1. An apparatus for moving thermal energy with respect to at least one of a beverage and a food product positioned in one of a vehicle and a stationary vending machine comprising: a vortex tube positionable in one of a vehicle and a stationary vending machine and having an inlet and a cold outlet and a hot outlet for dividing a primary air stream received in said inlet into a cold air sub-stream exiting said cold outlet and an a hot air sub-stream exiting said hot outlet; a containing member having a first wall with an inner surface for receiving a product and a second wall surrounding said first wall to define a first cavity; a first fluid line extending between said first cavity and one of said cold and hot outlets for communicating one of the cold and hot air sub-streams to said first cavity; and a third wall disposed between said first and second walls for dividing said first cavity into outer sub-cavity for receiving the air sub-stream and an inner sub-cavity for receiving a thermal fluid. 2. The apparatus of claim 2 wherein said containing member furthering comprises: an opening communicating with said inner sub-cavity for directing the thermal fluid to said inner sub-cavity; and an exit port spaced from said first inlet and communicating with said inner sub-cavity for directing the thermal fluid from said inner sub-cavity. 3. The apparatus of claim 1 further comprising: a water separator operably disposed upstream of said inlet to remove water from the primary air stream. 4. The apparatus of claim 1 further comprising: a second fluid line having first and second ends and extending away from said outer sub-cavity at said first end for communicating the received air sub-stream from said outer sub-cavity; a mixing chamber engaged with said second fluid line at said second end for receiving the received air sub-stream and having an aperture communicating with ambient air for mixing the received air sub-stream with ambient air; and a third fluid line extending away from said mixing chamber for communicating a mixture of ambient air and the received air sub-stream to said inlet. 5. The apparatus of claim 1 further comprising: a helical fin extending around said third wall in said outer sub-cavity. 6. The apparatus of claim 5 wherein said containing member furthering comprises: a second inlet communicating with said outer sub-cavity for directing the received air sub-stream to said outer sub-cavity; and a second outlet spaced from said second inlet and communicating with said outer sub-cavity for directing the received air sub-stream from said outer sub-cavity, wherein said helical fin directs the received air sub-stream between said second inlet and said second outlet. 7. The apparatus of claim 1 further comprising: an air directing device operably connected to said vortex tube for directing the primary air stream to said inlet of said vortex tube. 8. The apparatus of claim 7 wherein said air directing device is further defined as being a compressor mountable in a vehicle. | FIELD OF THE INVENTION The invention relates to a vortex cooler positionable in a vehicle or a stationary beverage machine. BACKGROUND OF THE INVENTION A vortex tube can divide a primary air stream into a cold air sub-stream and a hot air sub-stream. The origin of the vortex tube can be traced to a Frenchman named Georges Joseph Ranque. Mr. Ranque filed for a French patent on Dec. 12, 1931, and also secured U.S. Pat. No. 1,952,281 on Mar. 27, 1934. The application of a vortex tube to cooling system for a vehicle is disclosed in U.S. Pat. Nos. 5,819,541 and 5,950,436. SUMMARY OF THE INVENTION AND ADVANTAGES The invention provides an apparatus for moving thermal energy with respect to at least one of a beverage and a food product positioned in a vehicle or a stationary beverage machine. The apparatus includes a vortex tube positionable in a vehicle or a stationary beverage machine. The vortex tube includes an inlet and a cold outlet and a hot outlet. The vortex tube divides a primary air stream received in the inlet into a cold air sub-stream exiting the cold outlet and an a hot air sub-stream exiting the hot outlet. The apparatus also includes a containing member having a first wall with an inner surface for receiving a product. The containing member also includes a second wall surrounding the first wall to define a first cavity. The apparatus also includes a first fluid line extending between the first cavity and one of the cold and hot outlets for communicating one of the cold and hot air sub-streams to the first cavity. The apparatus also includes a third wall disposed between the first and second walls for dividing the first cavity into outer sub-cavity for receiving the air sub-stream and an inner sub-cavity for receiving a thermal fluid. BRIEF DESCRIPTION OF THE DRAWINGS Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: FIG. 1 is a schematic view of an exemplary embodiment of the inventive apparatus; and FIG. 2 is a perspective cross-sectional view of a containing member according to the exemplary embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An apparatus 10 for moving thermal energy with respect to at least one of a beverage and a food product is positionable in a vehicle or a stationary beverage machine. The apparatus 10 includes a vortex tube 12 positionable in a vehicle or a stationary beverage machine. The vortex tube 12 includes an inlet 14 and a cold outlet 16 and a hot outlet 18. The vortex tube 12 divides a primary air stream 40 received in the inlet 14 into a cold air sub-stream 42 exiting the cold outlet 16 and an a hot air sub-stream 44 exiting the hot outlet 18. The apparatus 10 also includes a containing member 20 having a first wall 22 with an inner surface 24 for receiving a product. The bottom of the inner surface 24 may be fitted with a lid to facilitate dispensing of the beverage cans fed from the top for cooling or heating. The containing member 20 also includes a second wall 26 surrounding the first wall 22 to define a first cavity 28. The apparatus 10 also includes a first fluid line 48 extending between the first cavity 28 and one of the cold and hot outlets 16, 18 for communicating one of the cold and hot air sub-streams 42, 44 to the first cavity 28. In the exemplary embodiment of the invention, the cold air sub-stream 42 is directed to the containing member 20 to cool a beverage and the hot air sub-stream 44 is released to the environment. However, in alternative embodiments of the invention, both of the air sub-streams 42, 44 could be directed to separate containing members, each being similar to the containing member 20. In another alternative embodiment of the invention, the hot air sub-stream 44 could be directed to the containing member 20 to heat a beverage. In other alternative embodiments of the invention, one of the air sub-streams 42, 44 could be directed to cool or heat, respectively, a food product disposed in the containing member 20. The apparatus 10 also includes a third wall 30 disposed between the first and second walls 22, 26 for dividing the first cavity 28 into outer sub-cavity 32 for receiving the air sub-stream 42, 44 and an inner sub-cavity 34 for receiving a thermal fluid. The thermal fluid can be a brine of water and salt or any other fluid. Preferably the brine disposed in the inner sub-cavity 34 has a relatively high thermal inertia. The brine enhances the transfer of thermal energy over a system utilizing only an air sub-stream by cooperating with the air sub-stream to expedite thermal transfer. The brine can be relatively stationary with respect to the containing member 20, or, in other words, static or non-flowing. A reservoir (not shown) can communicate additional brine to the inner sub-cavity 34 if necessary. The containing member 20 of the exemplary embodiment includes an opening 36 communicating with the inner sub-cavity 34 for directing the fluid to the inner sub-cavity 34. The containing member 20 also includes an exit port 38 spaced from the first inlet 14. The exit port 38 communicates with the inner sub-cavity 34 for directing the fluid from the inner sub-cavity 34. Preferably, the opening 36 and exit port 38 are disposed on opposite sides of the containing member 20. The opening 36 and exit port 38 can extend from the containing member 20 vertically, as shown in the exemplary embodiment, or one or both can extend horizontally with respect to the containing member 20. The apparatus 10 can also include a second inlet 68 communicates with the outer sub-cavity 32 for directing the received air sub-stream 42 to the outer sub-cavity 32. A second outlet 70 is spaced from the second inlet 68 and communicates with the outer sub-cavity 32 to direct the received air sub-stream 42 from the outer sub-cavity 32. A helical fin 66 extending around the third wall 30 in the outer sub-cavity 32 and directs the received air sub-stream 42 between the second inlet 68 and the second outlet 70. The apparatus 10 can also include a water separator 46 operably disposed upstream of the inlet 14 to remove water from the primary air stream 40. If the primary air stream 40 is relatively humid, ice can form in the vortex tube 12. The water separator 46 reduces the likelihood of ice formation, enhancing the operation of the apparatus 10. The apparatus 10 can also include a second fluid line 50. The second fluid line 50 extends from a first end 52 at the containing member 20 to a second end 54. The second fluid line 50 communicates the received air sub-stream 42 from the outer sub-cavity 32. A mixing chamber 56 engaged with the second fluid line 50 of the exemplary embodiment at the second end 54. The mixing chamber 56 receives the received air sub-stream 42. The mixing chamber 56 includes an aperture 58 communicating with ambient air 60. Ambient air 60 mixes with the received air sub-stream 42 in the mixing chamber to form a mixture 64. A third fluid line 62 extends away from the mixing chamber 56 and communicates the mixture 64 of ambient air 60 and the received sub-stream 42 to the inlet 14. The apparatus 10 can also include an air directing device 72 operably connected to the vortex tube 12. The air directing device 72 directs the primary air stream 40 to the inlet 14 of the vortex tube 12. The air directing device 72 can be a compressor mountable in a vehicle or a stationary beverage vending machine. The containing member 20 can receive, hold and dispense a plurality of beverages. For example, the inner surface 24 of the exemplary containing member 20 is cylindrical and can be sized to correspond to a beverage container such as a can. Beverage cans may be inserted in the upper open end of the first wall 22 (adjacent the second outlet 70). The lower end of the first wall 22 (adjacent the second inlet 68) can be operable to selectively open to dispense a beverage can. For example, the lower end of the first wall 22 can include a hinged door or a sliding plate to keep the lower end generally closed and to open to dispense a beverage in response to a command from a controller. The hinged door or sliding plate would be moveable by a controllable actuator. The first wall 22 can be extend a predetermined length corresponding to a plurality of beverage cans. While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>A vortex tube can divide a primary air stream into a cold air sub-stream and a hot air sub-stream. The origin of the vortex tube can be traced to a Frenchman named Georges Joseph Ranque. Mr. Ranque filed for a French patent on Dec. 12, 1931, and also secured U.S. Pat. No. 1,952,281 on Mar. 27, 1934. The application of a vortex tube to cooling system for a vehicle is disclosed in U.S. Pat. Nos. 5,819,541 and 5,950,436. | <SOH> SUMMARY OF THE INVENTION AND ADVANTAGES <EOH>The invention provides an apparatus for moving thermal energy with respect to at least one of a beverage and a food product positioned in a vehicle or a stationary beverage machine. The apparatus includes a vortex tube positionable in a vehicle or a stationary beverage machine. The vortex tube includes an inlet and a cold outlet and a hot outlet. The vortex tube divides a primary air stream received in the inlet into a cold air sub-stream exiting the cold outlet and an a hot air sub-stream exiting the hot outlet. The apparatus also includes a containing member having a first wall with an inner surface for receiving a product. The containing member also includes a second wall surrounding the first wall to define a first cavity. The apparatus also includes a first fluid line extending between the first cavity and one of the cold and hot outlets for communicating one of the cold and hot air sub-streams to the first cavity. The apparatus also includes a third wall disposed between the first and second walls for dividing the first cavity into outer sub-cavity for receiving the air sub-stream and an inner sub-cavity for receiving a thermal fluid. | 20050121 | 20071211 | 20060727 | 92097.0 | F25B902 | 0 | DOERRLER, WILLIAM CHARLES | VORTEX TUBE COOLER | UNDISCOUNTED | 0 | ACCEPTED | F25B | 2,005 |
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11,040,698 | ACCEPTED | Method for treating urinary incontinence in women and implantable device intended to correct urinary incontinence | The invention relates to a method and device for treating urinary incontinence in women. | 1-10. (canceled) 11. A method for treating urinary incontinence in a woman, said method comprising: (a) making a vaginal incision in the region of the middle third of the urethra measured from the meatus, and (b) positioning a tape under the urethra of said woman such that one portion of said tape extends from under the urethra through one obturator foramen of said woman and another portion of said tape extends from under the urethra through the other obturator foramen of said woman. 12. The method of claim 11, wherein a curved needle is used to extend one portion of said tape from under the urethra through one obturator foramen of said woman. 13. The method of claim 12, wherein a finger is inserted into said vaginal incision to guide said curved needle to said vaginal incision. 14. The method of claim 12, wherein said tape comprises a tapered end to be slipped into the eye of said curved needle. 15. The method of claim 11, wherein the ends of said tape are cut flush with the skin of said woman. 16. The method of claim 15, wherein the ends of said tape are tapered before being cut flush with the skin of said woman. | The invention relates to a method for treating urinary incontinence in women. It also relates to an implantable device intended to correct urinary incontinence in women. The said device is more particularly suited to the treatment of stress urinary incontinence. Various types of device have been proposed for treating phenomena of urinary incontinence in women. Thus, for example, document U.S. Pat. No. 5,899,909 describes a tape of constant width, made of a material of the meshed or knitted polypropylene type ensuring fibroblast colonization and thus anchorage into the tissues along its entire length. Once an incision has been made in the wall of the vagina this tape is positioned under the urethra, the tape being led upwards on each side of the bladder to be anchored into the abdominal wall. The method of fitting this tape is relatively tricky. Specifically, the needles being led vertically up alongside the bladder may not only pierce the latter, but may above all pierce the iliac artery or even the small intestine. In consequence, it is essential that cystoscopy be performed during the intervention. Document WO 98/35632 describes a device in the form of a tape, the central region of which is wider than the body of the tape, the assembly being made of a biocompatible material, particularly a woven material, allowing for fibroblast colonization. As before, each of the ends of the tape is led up alongside the bladder to be secured at the abdominal wall or, more specifically, in the bone of the pubis. Thus, the same drawbacks as before may be encountered. One of the objects of the invention is to artificially reconstruct the pelvic fascia by fitting tapes aimed at restoring, as faithfully as possible, the effective and natural situation of the endo-pelvic fascia, in its role of fibrous plug obturating the urogenital opening, the said fascia resting on either side of the said opening on the floor of the lifting muscles. Another of the stated objects of the present invention lies in solving the problems associated with subsequent surgical re-intervention in the region of the urethra; given the fact that the tapes proposed by the Prior Art are made, along their entire length, of a material capable of being colonized by fibroblasts, the problem arises of performing an intervention in this region if the tape, because of the fibroblast colonization, is anchored to the periurethral wall. A solution to this new problem is all the more important now that it has been found that the phenomenon of urinary incontinence may evolve to the fitting of an artificial sphincter. A problem such as this is neither disclosed nor suggested in the Prior Art. Furthermore, the literature has described possible phenomena of the migration of the substance of which the tape is made, particularly polypropylene, into the viscera. In order to solve all of these problems, the Applicant is proposing a method and an implantable device, intended to correct urinary incontinence in women. This method for treating urinary incontinence in women comprises the following steps: making a mediane paraurethral incision, practically in the middle third of the urethra, measured from the meatus, so as to allow the passage of a tape between the Alban fascia and the periurethral fascias; extending each of the free ends of the said tape in the region of the two obturator foramen of the iliac wing and leading them out into the groin opposite the corresponding foramen so that they essentially form a V shape, the point of which V passes under the urethra without changing the position thereof. In other words, and contrary to the surgical techniques employed in the state of the art, the tape is not led up alongside the bladder to form a U and thus be situated in close proximity to vital organs, but is on the contrary diverted from the bladder to form a V. Hence, no risk of damaging the bladder, the iliac artery or the small intestine is run. In consequence, it is not necessary to perform cystoscopy during the intervention. According to the invention, in order to make it easier to fit the tape which acts as an implant, a space is made between, on the one hand, the Alban fascia, the perineal muscular plane and the anterior insertion of the puborectal muscle and, on the other hand, the periurethral fascias. According to an advantageous version of the invention, the central region of the tape or implant, which region is intended to be inserted between the Alban fascia and the periurethral fascias, is coated with a substance capable of preventing any adhesion of the said fascias to the tape. Thus it becomes possible to avoid any cell growth on the tape between the wall of the vagina and the wall of the urethra, hence avoiding any anchorage of the tape in this region and thus to allow subsequent surgical re-intervention. Furthermore, coating it with such a substance in the region of the urethra makes it possible to avoid any migration of polypropylene into the viscera. The device according to the invention is characterized in that it is in the form of a tape of which the central region, intended to be inserted between the Alban fascia and the periurethral fascia, is coated with a substance capable of preventing any adhesion of the said fascias to the tape. In a first embodiment, the substance that prevents adhesion of the fascias to the tape is silicone. In a second embodiment, the substance is made of vegetable or animal growth factors. Of course, any substance capable of avoiding the adhesion of the fascias to the tape may be envisaged. The tape is coated on both side, advantageously on one side. Furthermore, the tape is made of any materials such as those known to those skilled in the art and, in particular but without applying any limitation, any material chosen from the group containing polyethylene and polypropylene. According to another feature, when the tape is made of polypropylene, the polypropylene is either meshed or knitted or alternatively is in the form of sprayed fibres. Nevetheless, the tape can also be made of absorbable material. In one advantageous embodiment, the central region of the tape is not as wide as the rest of the tape and this is so as to limit the area of contact in the region of the Alban fascia and of the periurethral fascia. Furthermore, and according to another feature, each of the ends of the tape has a tapered point intended to be anchored in the groin facing the corresponding obturator foramen. According to a preferred embodiment, the tape has a length equal to 60 cm and a width equal to 2.5 cm, and has a central region which is not as wide, being 1 cm wide over a length equal to 3 cm. Advantageously, the central region has a length equal to 15 mm. The invention and its ensuing advantages will emerge better from the following example in support of the appended figures. FIG. 1 is a diagrammatic depiction of the tape of the invention. FIG. 2 is a diagrammatic depiction of the position of the tape after fitting. As shown in FIG. 1, the device of the invention is in the form of a tape (1) of a length equal to 60 cm and of a width equal to 2.5 cm. This tape is made, along its entire length, of sprayed polypropylene fibres. According to an advantageous feature, the tape has, at its centre (2), a narrowing of length equal to 3 cm and of width equal to 1 cm, this portion being coated on both sides with a silicone-containing substance. Furthermore, each of its free ends (3, 4) is tapered. Fitting the device requires mini-invasive surgery, the main steps of which are described hereinafter. First of all, a mediane paraurethral incision is made in the region of the middle third of the urethra. One of the two obturator foramen, and more specifically the lower internal part is then identified by a finger slipped into the vaginal incision and an incision is made in the perineal skin opposite it, and so in the groin, so as to form an orifice through which an Emmet needle is then passed. This needle is introduced through this cutaneous incision firstly perpendicular to the perineum for about 15 mm (passing through the internal obturator muscle as far as just outside the ischiopubic branch), then the needle is allowed to describe its curvature, guided in this by the finger introduced opposite the obturator muscle through the vaginal incision. The pointed end of the tape is then slipped into the eye of the needle, emerging from the said vaginal incision, then pulled back through the thickness of muscle, the retractor and the internal obturator up to the surface of the skin. The tape is then placed between the Alban fascia and the periurethral fascias to position it in such a way that its central region, coated with silicone as appropriate, faces the said fascias. The tape is positioned without pulling behind the urethra. An incision is then made in the perineal skin facing the second obturator foramen, into which incision an Emmet needle is inserted. The free end of the tape is then slipped into the eye of the needle which is pulled back in the same way as before. The excess tape is then cut off flush with the skin then the skin is immobilized to disconnect it from the tape. The incision is finally closed with a stitch of quickly absorbable suture. FIG. 2 diagrammatically depicts the position, in cross section, of the tape after it has been fitted. As shown in this figure, once in place, the tape adopts the shape of a V, the branches of which are very far apart. Furthermore, it can also be seen that when the tape according to one of the advantageous embodiments of the invention is used, the silicone-coated segment of the tape is positioned between the uterus (5) and the vagina (6), while its ends (3, 4) are secured in the region of the groin (7, 8) facing the obturator foramen. Thanks to the robustness and texture of the tape, tension can be strong without there being any risk of rupture. The tape is positioned under the control of sight without employing cystoscopy. It is essential that there be no pulling on this tape which has to be slipped down under the urethra without altering the position thereof. It is apparent from the foregoing that the method according to the invention for treating urinary incontinence in women differs from the methods proposed in the state of the art through the simplicity of fitting of the tape, using mini-invasive surgery. Furthermore, it provides the urethra with firm suspension while at the same time maintaining a certain degree of flexibility and, most of all, keeping the vital organs in the vicinity relatively far away from the said tape. Furthermore, it plays a part in reconstructing the endopelvic fascia. | 20050121 | 20091124 | 20050616 | 89496.0 | 2 | LACYK, JOHN P | METHOD FOR TREATING URINARY INCONTINENCE IN WOMEN AND IMPLANTABLE DEVICE INTENDED TO CORRECT URINARY INCONTINENCE | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,040,723 | ACCEPTED | Image sensing apparatus | An image sensing apparatus according to one mode of the present invention enhances precision of WB adjustment to thereby obtain an image having an appropriate WB, and comprises an image signal processing circuit which adjusts the WB with respect to an image signal output from an image sensing element based on a WB gain, a ROM which stores at least a WB correction coefficient correspondence table, and a WB modification coefficient correspondence table, and a microcomputer which calculates a WB correction coefficient corresponding to a diaphragm value, and a WB modification coefficient based on the correspondence tables and which multiplies the WB gain by the WB correction coefficient and WB modification coefficient to thereby obtain a value as a digital gain and which executes a control in such a manner as to adjust the WB based on the digital gain. | 1. An image sensing apparatus comprising: image sensing section which has an image sensing element which picks up a subject image passed through a photographing lens having a diaphragm regulating a quantity of light to thereby output an image signal; storage section which stores a white balance modification coefficient further modifying a white balance correction coefficient in accordance with an optical characteristic of the image sensing section, the white balance correction coefficient performing white balance correction with respect to the image signal output from the image sensing section in accordance with an incidence characteristic upon the image sensing section based on optical characteristics including setting of the diaphragm of the photographing lens; and adjustment control section which performs white balance adjustment with respect to the image signal output from the image sensing section based on the white balance correction coefficient modified by the white balance modification coefficient. 2. The image sensing apparatus according to claim 1, wherein the photographing lens is detachably attached to the image sensing apparatus, and the white balance correction coefficient is stored in the photographing lens. 3. An image sensing apparatus comprising: image sensing section which picks up a subject image passed through an optical system to thereby output an image signal; image signal processing section which adjusts a white balance with respect to the image signal output from the image sensing section; and control section which reads a white balance correction coefficient which performs correction corresponding to a characteristic of a diaphragm of the optical system, and a white balance modification coefficient which further modifies the white balance correction coefficient and which performs correction corresponding to an optical characteristic of the image sensing section, calculating a digital gain which amplifies a signal for each color included in the image signal output from the image sensing section based on the white balance correction coefficient and the white balance modification coefficient, and executing a control by the digital gain in such a manner as to adjust the white balance by the image signal processing section. 4. The image sensing apparatus according to claim 3, wherein at least the image sensing section is detachably attached to the image sensing apparatus, and the white balance modification coefficient is stored in the image sensing section. 5. The image sensing apparatus according to claim 3, wherein the white balance correction coefficient includes at least a correction coefficient corresponding to a light receiving characteristic of a light receiving position outside an optical axis of a light receiving section picked up by the image sensing section, and the white balance modification coefficient has a coefficient which modifies a value of the white balance correction coefficient. 6. An image sensing apparatus capable of performing prior photographing to pick up an image of a subject which constitutes a white reference beforehand and accordingly calculate a gain for white balance adjustment prior to actual photographing, the apparatus comprising: image sensing section which picks up a subject image passed through an optical system to thereby output an image signal; image signal processing section which adjusts a white balance with respect to the image signal output from the image sensing section; and control section which reads a first white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system and corresponding to a diaphragm value at a prior photographing time at an actual photographing time, reading a second white balance correction coefficient further performing correction corresponding to the characteristic relating to the diaphragm of the optical system and corresponding to a diaphragm value at the actual photographing time, and a white balance modification coefficient further modifying the first and second white balance correction coefficients and performing correction corresponding to an optical characteristic of the image sensing section, calculating a digital gain amplifying a signal for each color included in the image signal output from the image sensing section by the white balance modification coefficient, and adjusting the white balance by the image signal processing means based on the digital gain. 7. An image sensing apparatus comprising: image sensing section which picks up a subject image passed through an optical system to thereby output an image signal; image signal processing section which adjusts a white balance based on the image signal output from the image sensing section; storage section which stores at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing section; and control section which calculates the white balance correction coefficient corresponding to a diaphragm value, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by the white balance correction coefficient and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing section, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing section. 8. The image sensing apparatus according to claim 7, wherein the second table is determined beforehand based on the optical characteristic of an image sensing element. 9. An image sensing apparatus comprising: image sensing section which picks up a subject image passed through an optical system to thereby output an image signal; image signal processing section which adjusts a white balance based on the image signal output from the image sensing section; storage section which stores at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing section; and control section which calculates a first white balance correction coefficient corresponding to a diaphragm value at a prior photographing time based on the first table, reading a second white balance correction coefficient corresponding to a diaphragm value at an actual photographing time, and a white balance modification coefficient based on the first and second tables, multiplying a white balance gain by a value obtained by dividing the second white balance correction coefficient by the first white balance correction coefficient, and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing section, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing means at the actual photographing time. 10. The image sensing apparatus according to claim 9, wherein the second table is determined beforehand based on an optical characteristic of an image sensing element. 11. An image sensing apparatus comprising: image sensing section which picks up a subject image passed through an optical system to thereby output an image signal; image signal processing section which adjusts a white balance with respect to the image signal output from the image sensing section based on a white balance gain; storage section which stores at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing section; switching section which switches a photographing mode; and control section which reads the white balance correction coefficient corresponding to the diaphragm value, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by the white balance correction coefficient and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing section, and executing a control based on the digital gain in such a manner as to adjust the white balance by the image signal processing section in a first photographing mode, and reading a first white balance correction coefficient corresponding to a diaphragm value at a prior photographing time based on the first table, reading a second white balance correction coefficient corresponding to a diaphragm value at an actual photographing time, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by a value obtained by dividing the second white balance correction coefficient by the first white balance correction coefficient, and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing section, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing section in a second photographing mode. 12. The image sensing apparatus according to claim 11, wherein the second table is determined beforehand based on an optical characteristic of an image sensing element. 13. An image sensing apparatus which picks up a subject image obtained by a replaceable photographing lens by image sensing section to thereby obtain image data, the apparatus comprising: correction coefficient storage section which stores a correction coefficient performing correction corresponding to an optical characteristic relating to the photographing lens; modification coefficient storage section which stores a modification coefficient modifying the correction coefficient in accordance with an optical characteristic relating to the image sensing section; and white balance adjustment section which adjusts a white balance of the image data obtained by the image sensing based on the correction coefficient and the modification coefficient corresponding to the applied photographing lens. 14. The image sensing apparatus according to claim 13, wherein the correction coefficient storage section is disposed in the photographing lens, the image sensing apparatus further comprising: communication section which receives the correction coefficient transmitted from the photographing lens. 15. The image sensing apparatus according to claim 13, wherein the modification coefficient storage section is disposed in an apparatus in which the image sensing section is disposed. 16. An image sensing apparatus comprising: image sensing section which picks up a subject image passed through a replaceable photographing lens by an image sensing element to thereby output an image signal; image signal processing section which adjusts a white balance with respect to the image signal output from the image sensing section; storage section which stores a white balance correction coefficient corresponding to an optical characteristic of the attached replaceable lens, and a white balance modification coefficient corresponding to an optical characteristic of the image sensing section; and control section which executes a control in such a manner as to adjust the white balance based on the white balance correction coefficient and the white balance modification coefficient. 17. The image sensing apparatus according to claim 16, wherein the white balance correction coefficient corresponding to the optical characteristic of the replaceable lens, and the white balance modification coefficient corresponding to the optical characteristic of the image sensing section are coefficients with respect to the image sensing element having an optical characteristic which is a reference. 18. An image sensing apparatus comprising: image sensing means having an image sensing element which picks up a subject image passed through a photographing lens having a diaphragm regulating a quantity of light to thereby output an image signal; storage means for storing a white balance modification coefficient further modifying a white balance correction coefficient in accordance with an optical characteristic of the image sensing means, the white balance correction coefficient performing white balance correction with respect to the image signal output from the image sensing means in accordance with an incidence characteristic upon the image sensing means based on optical characteristics including setting of the diaphragm of the photographing lens; and adjustment control means for performing white balance adjustment with respect to the image signal output from the image sensing means based on the white balance correction coefficient modified by the white balance modification coefficient. 19. An image sensing apparatus comprising: image sensing means for picking up a subject image passed through an optical system to thereby output an image signal; image signal processing means for adjusting a white balance with respect to the image signal output from the image sensing means; and control means for reading a white balance correction coefficient which performs correction corresponding to a characteristic of a diaphragm of the optical system, and a white balance modification coefficient which further modifies the white balance correction coefficient and which performs correction corresponding to an optical characteristic of the image sensing means, calculating a digital gain which amplifies a signal for each color included in the image signal output from the image sensing means based on the white balance correction coefficient and the white balance modification coefficient, and executing a control by the digital gain in such a manner as to adjust the white balance by the image signal processing means. 20. An image sensing apparatus capable of performing prior photographing to pick up an image of a subject which constitutes a white reference beforehand and accordingly calculate a gain for white balance adjustment prior to actual photographing, the apparatus comprising: image sensing means for picking up a subject image passed through an optical system to thereby output an image signal; image signal processing means for adjusting a white balance with respect to the image signal output from the image sensing means; and control means for reading a first white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system and corresponding to a diaphragm value at a prior photographing time at an actual photographing time, reading a second white balance correction coefficient further performing correction corresponding to the characteristic relating to the diaphragm of the optical system and corresponding to a diaphragm value at the actual photographing time, and a white balance modification coefficient further modifying the first and second white balance correction coefficients and performing correction corresponding to an optical characteristic of the image sensing means, calculating a digital gain amplifying a signal for each color included in the image signal output from the image sensing means by the white balance modification coefficient, and adjusting the white balance by the image signal processing means based on the digital gain. 21. An image sensing apparatus comprising: image sensing means for picking up a subject image passed through an optical system to thereby output an image signal; image signal processing means for adjusting a white balance based on the image signal output from the image sensing means; storage means for storing at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing means; and control means for calculating the white balance correction coefficient corresponding to a diaphragm value, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by the white balance correction coefficient and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing means, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing means. 22. An image sensing apparatus comprising: image sensing means for picking up a subject image passed through an optical system to thereby output an image signal; image signal processing means for adjusting a white balance based on the image signal output from the image sensing means; storage means for storing at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing means; and control means for calculating a first white balance correction coefficient corresponding to a diaphragm value at a prior photographing time based on the first table, reading a second white balance correction coefficient corresponding to a diaphragm value at an actual photographing time, and a white balance modification coefficient based on the first and second tables, multiplying a white balance gain by a value obtained by dividing the second white balance correction coefficient by the first white balance correction coefficient, and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing means, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing means at the actual photographing time. 23. An image sensing apparatus comprising: image sensing means for picking up a subject image passed through an optical system to thereby output an image signal; image signal processing means for adjusting a white balance with respect to the image signal output from the image sensing means based on a white balance gain; storage means for storing at least a first table in which a diaphragm value is associated with a white balance correction coefficient performing correction corresponding to a characteristic relating to a diaphragm of the optical system, and a second table in which the white balance correction coefficient is associated with a white balance modification coefficient further modifying the white balance correction coefficient and performing correction corresponding to an optical characteristic of the image sensing means; switching means for switching a photographing mode; and control means for reading the white balance correction coefficient corresponding to the diaphragm value, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by the white balance correction coefficient and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing means, and executing a control based on the digital gain in such a manner as to adjust the white balance by the image signal processing means in a first photographing mode, and reading a first white balance correction coefficient corresponding to a diaphragm value at a prior photographing time based on the first table, reading a second white balance correction coefficient corresponding to a diaphragm value at an actual photographing time, and the white balance modification coefficient based on the first and second tables, multiplying the white balance gain by a value obtained by dividing the second white balance correction coefficient by the first white balance correction coefficient, and the white balance modification coefficient to thereby obtain a value as a digital gain amplifying a signal for each color included in the image signal output from the image sensing means, and executing a control based on the digital gain to thereby adjust the white balance by the image signal processing means in a second photographing mode. 24. An image sensing apparatus which picks up a subject image obtained by a replaceable photographing lens by image sensing means to thereby obtain image data, the apparatus comprising: correction coefficient storage means for storing a correction coefficient performing correction corresponding to an optical characteristic relating to the photographing lens; modification coefficient storage means for storing a modification coefficient modifying the correction coefficient in accordance with an optical characteristic relating to the image sensing means; and white balance adjustment means for adjusting a white balance of the image data obtained by the image sensing based on the correction coefficient and the modification coefficient corresponding to the applied photographing lens. 25. An image sensing apparatus comprising: image sensing means for picking up a subject image passed through a replaceable photographing lens by an image sensing element to thereby output an image signal; image signal processing means for adjusting a white balance with respect to the image signal output from the image sensing means; storage means for storing a white balance correction coefficient corresponding to an optical characteristic of the attached replaceable lens, and a white balance modification coefficient corresponding to an optical characteristic of the image sensing means; and control means for executing a control in such a manner as to adjust the white balance based on the white balance correction coefficient and the white balance modification coefficient. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2004-017450, filed Jan. 26, 2004, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for adjusting white balance of an image sensing apparatus comprising an image sensing element. 2. Description of the Related Art For example, as shown in FIG. 11, many of image sensing elements have heretofore comprised a micro lens 100, a color filter 101 and the like for each pixel in order to enhance a condensing ratio per pixel. A refractive index of the micro lens 100 depends on a wavelength of incident light (dependence on the wavelength). Especially, as shown in FIG. 11, when the light strikes from an oblique direction of the micro lens 100, the above-described dependence on the wavelength becomes remarkable, and light having a wavelength that is not condensed on a light receiving section 102 is also generated (oblique incidence characteristic). BRIEF SUMMARY OF THE INVENTION An object of one mode of the present invention is to obtain images having an appropriate white balance even in any combination in an image sensing apparatus capable of enhancing precision of white balance adjustment and changing a photographing lens or an image sensing element. To achieve this object, according to one mode of the present invention, there is provided an image sensing apparatus comprising: an image sensing section having an image sensing element which picks up a subject image passed through a photographing lens having a diaphragm regulating a quantity of light to thereby output an image signal; a storage section which stores a white balance modification coefficient to further modify a white balance correction coefficient in accordance with an optical characteristic of the image sensing section, the white balance correction coefficient performing white balance correction with respect to the image signal output from the image sensing section in accordance with an incidence characteristic upon the image sensing element based on optical characteristics including setting of the diaphragm of the photographing lens; and an adjustment control section which performs white balance adjustment with respect to the image signal output from the image sensing section based on the white balance correction coefficient modified by the white balance modification coefficient. Advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. FIG. 1 is a constitution diagram of an image sensing apparatus according to a first embodiment of the present invention; FIG. 2 is a diagram showing a spectral sensitivity distribution of an image sensing element; FIG. 3 is a diagram showing dependence of light receiving sensitivity of the image sensing element on an incidence angle; FIG. 4 is a diagram showing dependence of an output of the image sensing element on F value; FIG. 5 is a diagram showing a WB correction coefficient correspondence table; FIG. 6 is a diagram showing a WB modification coefficient correspondence table; FIG. 7 is a flowchart showing an operation at a prior photographing time of the image sensing apparatus according to the first embodiment of the present invention; FIG. 8 is a flowchart showing an operation at an actual photographing time of the image sensing apparatus according to the first embodiment of the present invention; FIG. 9 is a diagram showing a WB correction coefficient correspondence table; FIG. 10 is a diagram showing a WB modification coefficient correspondence table; and FIG. 11 is an explanatory view of dependence on wavelength, and oblique incidence characteristic of the image sensing element according to a conventional technique. DETAILED DESCRIPTION OF THE INVENTION First Embodiment First, a constitution of an image sensing apparatus according to a first embodiment of the present invention will be described with reference to FIG. 1. Here, a camera system in which a camera main body is combined with a replaceable photographing lens (hereinafter referred to as a replaceable lens) will be described as an example of this image sensing apparatus. As shown in FIG. 1, the camera system which is the image sensing apparatus according to the first embodiment of the present invention has a lens module 1, an image sensing module 2, a RAM 3, an image signal processing circuit 4, a microcomputer 5, a ROM 6, an EEPROM 7, a mode setting SW 8, a recording medium 9 and the like. The lens module 1 is disposed on the side of the replaceable lens. Other constituting elements are disposed on the side of a camera main body to which the replaceable lens is attachable. In the lens module 1 on the replaceable lens side, an optical system 1a including a photographing lens, zoom lens, diaphragm and the like, a microcomputer 1b which controls the whole lens module, a ROM 1c in which various data and the like are stored, a communication section 1d and the like are disposed. At least a first table is stored in this ROM 1c as described later in detail. The lens module 1 is detachably connected to the image sensing module 2 via a connecter, and is electrically connected to the same via a communication section id and 2d. The communication sections 1d and 2d are constituted as connectors. Moreover, the image sensing module 2 on the camera main body side is provided with an image sensing element 2a such as a CCD, an interface (hereinafter referred to as I/F) circuit 2b, and a ROM 2c for temporarily storing various data. The RAM 3 interposed between the image sensing module 2 and the image signal processing circuit 4 stores an image signal sent from the I/F circuit 2b. The image sensing module 2 is detachably connected to the camera main body side via a connecter, and is electrically connected to the same via a communication section 10. In more detail, the image signal processing circuit 4 has a digital gain circuit 4a, a synchronization circuit 4b, a color conversion circuit 4c, and a gamma conversion circuit 4d. The digital gain circuit 4a amplifies an red (R) signal, a green (Gr) signal, a green (Gb) signal, and a blue (B) signal which are image signals for colors, temporarily stored in the RAM 3 with digital gains calculated by the microcomputer 5 in a method described later in detail, and accordingly outputs an R′ signal, a Gr′ signal, a Gb′ signal, and a B′ signal as level-adjusted signals. That is, the digital gains amplify the signal for each color, included in the image signals output from the image sensing element 2a. Moreover, the synchronization circuit 4b includes a sample holding circuit (not shown) and the like, performs a synchronization process of the R′, Gr′, Gb′, and B′ signals, and outputs the R, G, and B signals. The color conversion circuit 4c subjects these R, G, and B signals to color conversion, and outputs R′, G′, and B′ signals. The gamma conversion circuit 4d γ-converts these R′, G′, and B′ signals, and records the results in the recording medium 9. Additionally, the ROM 6 stores at least a second table described later in detail. The EEPROM 7 stores various data. The mode setting SW 8 switches various modes. It is to be noted that image sensing means described in claims corresponds to the image sensing element 2a, image sensing module 2 including the element or the like, image signal processing means corresponds to the image signal processing circuit 4 or the like, storage means corresponds to the ROM 1c in the lens module 1, the ROM 6 on the camera main body side or the like, and control means corresponds to the microcomputer 5 or the like. Correction coefficient storage means described in claims corresponds to the ROM 1c of the lens module 1 or the like, modification coefficient storage means corresponds to the ROM 6 or the like, and white balance adjustment means corresponds to the image signal processing circuit 4 or the like. Moreover, communication means corresponds to the communication section 1d, 10 or the like. Additionally, the present invention is not limited to the above-described relations. In this constitution, a subject image which has struck via the photographing lens, zoom lens, and diaphragm of the optical system 1a of the lens module 1 is picked up by the image sensing element 2a of the image sensing module 2, and an image signal is output, and stored in the RAM 3 via the I/F circuit 2b. In the ROM 1c of the lens module 1 on the replaceable lens side, at least the first table is stored in which diaphragm values are associated with white balance (hereinafter referred to as WB) correction coefficients for performing correction corresponding to characteristics relating to the diaphragm of the optical system 1a. Here, the WB correction coefficient is a coefficient for performing the correction corresponding to the characteristics relating to the diaphragm of the optical system 1a in the first embodiment. On the other hand, in the ROM 6 on the camera main body side, the WB modification coefficient further modifies the WB correction coefficient. In the ROM 6, at least a second table is stored in which the correction coefficient is associated with the WB modification coefficient for performing the correction corresponding to optical characteristics of the image sensing element 2a. Here, the WB modification coefficient further modifies the WB correction coefficient, and performs the correction corresponding to the optical characteristics of the image sensing element 2a for use. This second table is predetermined based on the optical characteristics of the image sensing element 2a. The storage place of each table is one example, and, needless to say, the present invention is not limited to this. The microcomputer 5 calculates the digital gains based on a WB mode set by the mode setting SW 8. Here, two different WB modes will be described hereinafter as first and second WB modes. For example, an operation of the first WB mode will be performed as follows. That is, the WB correction coefficient corresponding to the diaphragm value, and the WB modification coefficient are calculated based on the first and second tables. Moreover, values obtained by multiplying the WB gains by the WB correction and modification coefficients are digital gains for amplifying the signals for the respective colors included in the image signals output from the image sensing element 2a. Digital gain=WB gain×WB correction coefficient×WB modification coefficient (1) WB adjustment is controlled to be performed based on the digital gain by the image signal processing circuit 4. The image signal of the RAM 3 is read by the image signal processing circuit 4, and the image signal is subjected to white balance adjustment based on the digital gain calculated as described above. On the other hand, an operation of a second WB mode will be performed as follows. That is, the microcomputer 5 calculates a first WB correction coefficient corresponding the diaphragm value at a prior photographing time based on the first table. Here, the prior photographing refers to the photographing which is performed prior to actual photographing of the subject image in order to obtain predetermined data, and the photographing of the actual desired subject image will be referred to as the actual photographing. Furthermore, a second WB correction coefficient corresponding the diaphragm value at the time of the actual photographing, and the WB modification coefficient are read based on the first and second tables. Moreover, a value of the WB gain multiplied by a value obtained by dividing the second WB correction coefficient by the first WB correction coefficient, and the WB modification coefficient is obtained as the digital gain for amplifying the signal for each color included in the image signal output from the image sensing element 2a. Digital gain=WB gain×(WB correction coefficient (F value at actual photographing time)/WB correction coefficient (F value at prior photographing time))×WB modification coefficient (WB correction coefficient at actual photographing time) (2) The WB adjustment by the image signal processing circuit 4 is controlled to be performed based on this digital gain. The image signal of the RAM 3 is read by the image signal processing circuit 4, and the WB adjustment is performed with respect to the image signal based on the digital gain calculated as described above. Here, a spectral sensitivity distribution of the image sensing element will be described with reference to FIG. 2. The image sensing element 2a has spectral sensitivity characteristics shown in FIG. 2. The characteristics of R, G, and B light components are as shown in FIG. 2. Sensitivities of human eyes with respect to the colors are strongest with respect to G light components, and the G light components are seen brightest. It is to be noted that the image sensing module 2 including this image sensing element 2a can be replaced with another image sensing module including an image sensing element having different optical characteristics. Accordingly, image sensing modules suitable for photographing purposes are usable such as an image sensing module suitable for nighttime photographing, and an image sensing module suitable for a broad dynamic range. Dependence of light receiving sensitivity of the image sensing element on an incidence angle will be described with reference to FIG. 3. As shown in FIG. 3, the image sensing element 2a has dependence on the incidence angle, and a relative sensitivity fluctuates by the incidence angle of the light. That is, as the incidence angle of the light increases, a difference is generated in a drop of the relative sensitivity with respect to each of the R, G, and B light components. A drop degree represented as the relative sensitivity (R/G, B/G) especially with respect to the G light component increases. Furthermore, a degree of the fluctuation differs for each image sensing element by fluctuations in designing a micro lens or manufacturing the image sensing element 2a. Dependence of an output of the image sensing element on an F value will be described with reference to FIG. 4. As shown in FIG. 4, even when micro lenses disposed for pixels are prepared under the same design, a 1/F value increases in a relation between an inverse number (1/F) of an F value and relative sensitivity (R/G, B/G) (i.e., the diaphragm opens), and accordingly a drop is generated in the relative sensitivity with respect to R, G, and B light components. Moreover, a degree of the drop of the relative sensitivity largely differs with each light component. In view of the above-described properties, in the image sensing apparatus according to the first embodiment of the present invention, the digital gain is calculated using a WB correction coefficient correspondence table which is the first table, and a WB modification coefficient correspondence table which is the second table, and the signal for each color is amplified with the digital gain. This will be described hereinafter in detail. First, the WB correction coefficient correspondence table will be described with reference to FIG. 5. As shown in FIG. 5, in the WB correction coefficient correspondence table, diaphragm values are associated with WB correction coefficients of R, B signals. In this WB correction coefficient correspondence table, one selected image sensing element is positioned with an image sensing element which is a reference, and correction coefficients of gains of the R and B signals are determined in consideration of the dependence of the image sensing element constituting the reference on the incidence angle. As described above, as to the dependence of the image sensing element on the incidence angle, when the incidence angle increases, the drop of the relative sensitivity with respect to the R and B signals remarkably appears, and this WB correction coefficient compensates for this drop. It is to be noted that the WB correction coefficient correspondence table is stored, for example, in the ROM 1c in the lens module 1 of FIG. 1. Next, a WB modification coefficient correspondence table will be described with reference to FIG. 6. As shown in FIG. 6, in the WB modification coefficient correspondence table, the WB correction coefficients read from FIG. 5 are associated with WB modification coefficients of R and B signals. For example, when this WB correction coefficient is 1.03, a WB modification coefficient_R corresponding to the optical characteristic of the image sensing element 2a is 1.01, and a WB modification coefficient_B is 0.99 from the WB modification coefficient correspondence table. It is to be noted that this WB modification coefficient correspondence table is stored in the ROM 2c of the image sensing module. In the image sensing apparatus according to this embodiment, the microcomputer 5 calculates the digital gain referring to the correspondence tables of FIGS. 5 and 6. More concretely, the microcomputer 5 reads a WB correction coefficient_R and a WB correction coefficient_B corresponding to the diaphragm value of the optical system 1a from the ROM 1c referring to the correspondence table of FIG. 5. Moreover, the microcomputer reads the WB modification coefficient_R corresponding to the WB correction coefficient_R, and the WB modification coefficient_B corresponding to the WB correction coefficient_B from the ROM 6 referring to the correspondence table of FIG. 6. Furthermore, the microcomputer calculates the digital gain based on them. For example, the microcomputer 5 calculates the digital gain based on equation (1) in the first WB mode, and based on equation (2) in the second WB mode. An operation at the time of the prior photographing of the image sensing apparatus according to the first embodiment of the present invention will be described hereinafter in detail with reference to a flowchart of FIG. 5, and appropriately with reference to FIGS. 5, 6 here. A release switch (not shown) is turned on to enter the operation at the time of the prior photographing, and then the microcomputer 5 first performs predetermined photometry calculation, exposure control, and image sensing control (steps S1 to S3). Moreover, the microcomputer stores image sensing data (image signal) from the image sensing element 2a in the RAM 3 (step S4). Next, the microcomputer 5 detects the WB gain based on the image signal (step S5), and stores the WB gain in the EEPROM 7 (step S6). Furthermore, the microcomputer stores the F value at the prior photographing time in the EEPROM 7 (step S7), and ends the operation at the prior photographing time. By the above-described process according to one example, the WB gain at the prior photographing time, for use in subsequent processes, is associated with the F value, and stored in the EEPROM 7. Next, an operation at the time of the actual photographing of the image sensing apparatus according to the first embodiment of the present invention will be described in detail with reference to a flowchart of FIG. 8, and appropriately with reference to FIGS. 5, 6 here. When entering the operation at the actual photographing time, first the microcomputer 5 performs predetermined photometry calculation, exposure control, and image sensing control (steps S11 to S13). The image sensing element 2a stores image sensing data (image signal) in the RAM 3 (step S14). Next, the microcomputer reads the WB correction coefficient_R and WB correction coefficient_B corresponding to the F value at the actual photographing time (from the ROM 1c) referring to the WB correction coefficient correspondence table of FIG. 5 (step S15). Furthermore, the microcomputer reads the WB modification coefficient_R and WB modification coefficient_B corresponding to the WB correction coefficient_R and WB correction coefficient_B (from the ROM 6) referring to the WB modification coefficient correspondence table of FIG. 6 (step S16). Next, the microcomputer 5 judges whether the WB mode is set to any of an automatic WB (hereinafter referred to as AWB), manual WB (hereinafter referred to as MWB), and one-touch WB (hereinafter referred to as OTWB) in the mode setting SW 8 (step S17). Here, the AWB mode is a mode in which white balance adjustment suitable for a scene is automatically performed based on image sensing data. In the MWB mode, the white balance adjustment suitable for the scene is manually designated beforehand by a photographer. Moreover, in the OTWB mode, the white balance is adjusted based on a white balance adjustment gain obtained beforehand by picking up a subject image which is a white reference. First, when judging that the AWB mode is set in the step S17, the microcomputer 5 analyzes the image sensing data, and performs judgment concerning the WB gain (step S18). Moreover, the WB correction coefficient_R and WB correction coefficient_B read in the step S15, the WB modification coefficient_R and WB modification coefficient_B read in the step S16, and the WB gain obtained in the step S18 are substituted into the calculation equation (1), and accordingly the digital gains of the R and B signals are calculated (step S19). Thereafter, the process advances to processes of and after step S25. On the other hand, when judging that the MWB mode is set in the step S17, the microcomputer 5 reads the WB gain designated beforehand by the photographer from the ROM 6 (step S20). Moreover, the process advances to an MWB side of the judgment of the step S21. The microcomputer substitutes the WB correction coefficient_R and WB correction coefficient_B read in the step S15, the WB modification coefficient_R and WB modification coefficient_B read in the step S16, and the WB gain at the prior photographing time obtained in the step S20 into the calculation equation (1), and calculates the digital gains of the R and B signals (step S19). Thereafter, the process advances to the processes of and after the step S25. Here, the white balance adjustment gain designated in the MWB mode is stored beforehand in the ROM 6. Furthermore, when judging that the OTWB mode is set in the step S17, the microcomputer 5 reads the WB gain obtained at the prior photographing time (from the EEPROM 7) (step S20). Moreover, the process advances to an OTWB side of the judgment of the step S21. The microcomputer reads the F value at the prior photographing time (step S22), and reads the WB correction coefficient at the prior photographing time from the EEPROM 7 (step S23). Moreover, the microcomputer substitutes the WB correction coefficient_R and WB correction coefficient_B at the actual photographing time read in the step S15, the WB gain at the prior photographing time read in the step S20, and the F value at the prior photographing time, and the WB correction coefficient_R and WB correction coefficient_B read in the steps S22, 23 into the calculation equation (2), and calculates the digital gains of the R and B signals (step S24). Thereafter, the process advances to the processes of and after the step S25. Thus, the digital gain circuit 4a amplifies R, Gr, Gb, and B signals which are image signals temporarily stored in the RAM 3 with the digital gain calculated by the microcomputer 5 to thereby adjust levels, and outputs R′, Gr′, Gb′, and B′ signals (step S25). Furthermore, the synchronization circuit 4b performs synchronization of the R′, Gr′, Gb′, and B′ signals, and outputs the R, G, and B signals. Moreover, the color conversion circuit 4c subjects the R, G, and B signals to color conversion, and outputs R′, G′, and B′ signals. Furthermore, the gamma conversion circuit 4d subjects these R′, G′, and B′ signals to γ conversion (step S26). Results obtained in this manner are recorded in the recording medium 9 (step S27). Second Embodiment An image sensing apparatus according to a second embodiment of the present invention will be described in a case where an image sensing module comprising a CCD having a WB modification coefficient correspondence table of FIG. 9 and characteristics is attached instead of the image sensing module comprising the CCD having the WB modification coefficient correspondence table of FIG. 6 and the characteristics. In this CCD of the image sensing module, a CCD (hereinafter referred to as a narrow pitch module) having an adjacent pixel pitch narrower than that of an image sensing element 2a is used. Here, as shown in FIG. 1, the image sensing module is electrically connected to a lens module via a communication section 1d and 2d. The image sensing module is electrically connected to a microcomputer, RAM 3 and the like of the image sensing apparatus via a communication section 10. The communication sections 1d, 2d and 10 are constituted as connectors, and the image sensing module is accordingly set to be attachable/detachable in this example. In the image sensing apparatus according to the second embodiment of the present invention, a digital gain is calculated using a WB correction coefficient correspondence table of FIG. 5 which is a first table and a WB modification coefficient correspondence table of FIG. 9 which is a second table, and a signal for each color is amplified with the digital gain. This will be described hereinafter in detail. Since FIG. 5 has been described above in the embodiment, the description is omitted here. The WB modification coefficient correspondence table of FIG. 9 will be described. As shown in FIG. 9, in the WB modification coefficient correspondence table, WB correction coefficients read from FIG. 5 are associated with WB modification coefficients of R and B signals. Here, by the WB modification coefficients of FIG. 9, excessive/insufficient correction with respect to optical characteristics of an image sensing element which is a reference is further modified. When the WB correction coefficient is corrected by the WB modification coefficient having this narrow pitch module, for example, correction can be performed in the same manner as in appropriate WB correction performed in the first embodiment. In comparison of FIG. 9 with FIG. 6, through regulation, the WB modification coefficients of FIG. 9 corresponding to the narrow pitch module is more strongly influenced by incidence angles, and therefore the modification coefficients have increasing modification amounts. It is to be noted that correspondence between the modification coefficient and each diaphragm, and resolution of precision may be varied in such a manner as to achieve optimum correction by the optical characteristics of the image sensing element of the attached image sensing module. For example, the correspondence between the modification coefficient and each diaphragm value may be adjusted into the resolution in accordance with a correction amount, or the correction coefficients with respect to zoom positions may be set with respect to not only TELE, WIDE positions but also different focal distances. This WB modification coefficient correspondence table is stored in an ROM 2c of an image sensing module 2 in the same manner as in the first embodiment. Third Embodiment An image sensing apparatus according to a third embodiment of the present invention will be described in a case where a lens module (hereinafter referred to as a zoom lens module) comprising a zoom lens having a WB correction coefficient correspondence table of FIG. 10, instead of the WB correction coefficient correspondence table of FIG. 5 described above, and characteristics is attached. Here, as shown in FIG. 1, an image sensing module is electrically connected to the zoom lens module via a communication section 1d and 2d. The communication section id and 2d are constituted as a connector, and accordingly set to be attachable/detachable in the same manner as in the second embodiment. In the image sensing apparatus according to the third embodiment of the present invention, a digital gain is calculated using a WB correction coefficient correspondence table of FIG. 10 which is a first table and a WB modification coefficient correspondence table of FIG. 6 which is a second table, and a signal for each color is amplified with the digital gain. This will be described hereinafter in detail. The WB correction coefficient correspondence table of FIG. 10 will be described hereinafter. In the zoom lens, an influence of a diaphragm of a luminous flux which enters an image sensing element differs with a focal distance. Therefore, as shown in FIG. 5, in the WB correction coefficient correspondence table, diaphragm values are associated with WB correction coefficients of the R and B signals in focal distances on a wide angle side (WIDE) and a telescope side (TELE). It is to be noted that the WB correction coefficient correspondence table is stored, for example, in an ROM 1c in the zoom lens module. Here, the WB correction coefficients of FIG. 10 indicate excess/shortage of correction with respect to optical characteristics of a photographing lens which is a reference. When the correction is performed by the WB correction coefficient of the zoom lens module and the WB modification coefficient of the image sensing module, for example, correction can be performed in the same manner as in appropriate WB correction performed in the first embodiment. As seen from FIG. 10, in a short focal distance (i.e., the wide side), the correction value of the WB correction coefficient is larger even in the same diaphragm. It is to be noted that correspondence between the modification coefficient and each diaphragm, and resolution of precision may be varied in such a manner as to achieve optimum correction by the optical characteristics of the photographing lens of the attached lens module. Even when the combination of the lens module with the image sensing module is changed as described above, or in any of the above-described embodiments, the appropriate WB correction can be performed. As described above, according to the embodiments of the present invention, the precision of the WB adjustment is enhanced, so-called color fogging phenomenon is suppressed, and an appropriately exposed image is obtained. Moreover, in the calculation of the digital gain relating to the WB adjustment, a preferable process can be performed in accordance with various photographing modes. Furthermore, the WB adjustment can be performed fully considering the fluctuations of the image sensing element at a manufacturing time, optical characteristics of the micro lens and the like. The first to third embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and can be variously modified/changed within the scope of the present invention. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general invention concept as defined by the appended claims and their equivalents. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a technique for adjusting white balance of an image sensing apparatus comprising an image sensing element. 2. Description of the Related Art For example, as shown in FIG. 11 , many of image sensing elements have heretofore comprised a micro lens 100 , a color filter 101 and the like for each pixel in order to enhance a condensing ratio per pixel. A refractive index of the micro lens 100 depends on a wavelength of incident light (dependence on the wavelength). Especially, as shown in FIG. 11 , when the light strikes from an oblique direction of the micro lens 100 , the above-described dependence on the wavelength becomes remarkable, and light having a wavelength that is not condensed on a light receiving section 102 is also generated (oblique incidence characteristic). | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>An object of one mode of the present invention is to obtain images having an appropriate white balance even in any combination in an image sensing apparatus capable of enhancing precision of white balance adjustment and changing a photographing lens or an image sensing element. To achieve this object, according to one mode of the present invention, there is provided an image sensing apparatus comprising: an image sensing section having an image sensing element which picks up a subject image passed through a photographing lens having a diaphragm regulating a quantity of light to thereby output an image signal; a storage section which stores a white balance modification coefficient to further modify a white balance correction coefficient in accordance with an optical characteristic of the image sensing section, the white balance correction coefficient performing white balance correction with respect to the image signal output from the image sensing section in accordance with an incidence characteristic upon the image sensing element based on optical characteristics including setting of the diaphragm of the photographing lens; and an adjustment control section which performs white balance adjustment with respect to the image signal output from the image sensing section based on the white balance correction coefficient modified by the white balance modification coefficient. Advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. | 20050121 | 20090825 | 20050728 | 95530.0 | 0 | LAM, HUNG H | IMAGE SENSING APPARATUS WHICH DETERMINES WHITE BALANCE CORRECTION INFORMATION BEFORE PHOTOGRAPHING | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,195 | ACCEPTED | Machine and method for deployment of OS image | The present invention provides a deployment technique that can distribute OS images at a high speed. The system of the present invention comprises a deployment machine (hereafter abbreviated to “DM”), a plurality of servers which are connected to the DM via a first communications network, and a storage system which is connected to the DM and the plurality of servers via a second communications network. The storage system comprises a plurality of server storage devices that respectively correspond to the plurality of servers, and an original storage device in which an OS image is stored. The DM transmits a first instruction to produce the OS image inside the original storage device in each of the plurality of server storage devices to the storage system, and after the OS image inside the original storage device is produced in each of the plurality of server storage devices in accordance with the first instruction, the respective servers read the OS images in the server storage devices corresponding to themselves via the second communications network, and start the OS. | 1. A deployment machine which prepares a plurality of OS images that are respectively used in a plurality of information processing terminals, this deployment machine being coupled to a first communications network and a second communications network to which a plurality of information processing terminals and one or more storage systems are connected, and this deployment machine comprising: a volume preparation part which causes said one or more storage systems to prepare a plurality of terminal logical volumes respectively corresponding to said plurality of information processing terminals insides aid one or more storage systems; an OS image copying part which causes said one or more storage systems to copy the OS image data stored in the logical volumes into each of the one or more terminal logical volumes selected from said plurality of terminal logical volumes without passing through said first communications network, which has a slower transfer rate than said second communications network; and a boot path setting part which is a part that sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to said one or more terminal volumes, and which sets boot paths that are used to access said copied OS image data via said second communications network. 2. The deployment machine according to claim 1, wherein said boot path setting part executes the processing of (1) or (2) below: (1) one or more boot path names respectively corresponding to said one or more information processing terminals are respectively transmitted to said one or more information processing terminals via said first communications network; or (2) in cases where access path names for said terminal logical volumes are defined inside said one or more storage systems, said access path names are changed to boot path names that are preset for the information processing terminals corresponding to said terminal logical volumes. 3. The deployment machine according to claim 1, wherein in cases where data is transmitted to an information processing terminal selected from said one or more information processing terminals, if the power supply of said selected information processing terminal is in an “off” state, said data is transmitted to selected information processing terminal via said first communications network after the power supply of said selected information processing terminal is turned on. 4. The deployment machine according to claim 1, wherein said OS image data copying part executes the processing of (1) or (2) below: (1) two or more terminal logical volumes selected from said plurality of terminal logical volumes are formed into a pair with each other, the OS image data inside said logical volumes is read out via said second communications network, and said read-out OS image data is written all at one time via said second communications network into said two or more terminal logical volumes that are formed into a pair with each other; or (2) said logical volume storing the OS image data and said one or more selected terminal logical volumes are formed into a pair, and said one or more storage systems are controlled so that the OS image data inside said OS image volume is copied all at one time into said one or more terminal logical volumes. 5. The deployment machine according to claim 1, further comprising an information setting part which sets unique setting information that is contained in terminal information in a terminal information table in which a plurality of sets of terminal information respectively corresponding to said plurality of information processing terminals are recorded, and that is to be set in said information processing terminals when said information processing terminals start the OS, in the information processing terminals in which said unique setting information is to be set. 6. The deployment machine according to claim 5, wherein said information setting part executes the processing of (1) or (2) below: (1) said acquired unique setting information is written into the terminal logical volumes of the information processing terminals in which said acquired unique setting information is to be set via said second communications network; or (2) information or a computer program that is used to set said acquired unique setting information is transmitted to the information processing terminals in which said acquired unique setting information is to be set via said first communications network. 7. The deployment machine according to claim 1, wherein said volume preparation part acquires the OS image data size and one or more different data sizes respectively corresponding to one or more different types of data stored in the terminal logical volume of the information processing terminal selected from said plurality of information processing terminals, and prepares a logical volume having a storage capacity that is equal to or greater than the total of the acquired OS image data size and said one or more different data sizes as the terminal logical volume of said selected information processing terminal. 8. A method for preparing a plurality of OS images that are respectively used in a plurality of information processing terminals, comprising: causing one or more storage systems connected to a first communications network and a second communications network to prepare a plurality of terminal logical volumes respectively corresponding to said plurality of information processing terminals coupled to the first communications network and the second communications network in said one or more storage systems; causing said one or more storage systems to copy the OS image data stored in the logical volumes inside said one or more storage systems in each of the one or more terminal logical volumes selected from said plurality of terminal logical volumes without passing through said first communications network whose transfer rate is slower than that of said second communications network; and setting a dedicated boot path for each of said one or more information processing terminals respectively corresponding to said one or more terminal volumes, wherein the boot paths are for accessing said copied OS image data via said second communications network. 9. The method according to claim 8, wherein the processing of (1) or (2) below is executed in the step of setting the boot paths: (1) one or more boot path names respectively corresponding to said one or more information processing terminals are respectively transmitted to said one or more information processing terminals via said first communications network; or (2) in cases where access path names for said terminal logical volumes are defined inside said one or more storage systems, said access path names are changes to boot path names that are preset in the information processing terminals corresponding to said terminal logical volumes. 10. The method according to claim 8, wherein the processing of (1) or (2) below is executed in said copying step: (1) two or more terminal logical volumes selected from said plurality of terminal logical volumes are formed into a pair with each other, the OS image data inside said logical volumes is read out via said second communications network, and said read-out OS image data is written all at one time into said two or more terminal logical volumes that are formed into pairs with each other via said second communications network; or (2) said logical volume in which the OS image data is stored and said one or more selected terminal logical volumes are formed into a pair with each other, and said one or more storage systems are controlled so that the OS image data inside said OS image volume is copied all at one time into said one or more terminal logical volumes. 11. The method according to claim 8, further comprising the step of setting unique setting information that is included in terminal information in a terminal control table in which a plurality of sets of said terminal information respectively corresponding to said plurality of information processing terminals, and that is to be set in said information processing terminals when said information processing terminals start the OS, in each of said one or more information processing terminals. 12. The method according to claim 11, wherein the processing of (1) or (2) below is executed in the setting step: (1) one or more boot path names respectively corresponding to said one or more information processing terminals are respectively transmitted to said one or more information processing terminals via said first communications network; or (2) in cases where access path names for said terminal logical volumes are defined inside said one or more storage systems, said access path names are changed to boot path names that are preset in the information processing terminals corresponding to said terminal logical volumes. 13. A computer program which is used to prepare a plurality of OS images that are respectively used in a plurality of information processing terminals, which causes a computer to execute: causing one or more storage systems coupled to a first communications network and a second communications network to prepare a plurality of terminal logical volumes respectively corresponding to said plurality of information processing terminals connected to the first communications network and the second communications network in said one or more storage systems; causing said one or more storage systems to copy the OS image data stored in the logical volumes inside said one or more storage systems into each of the one or more terminal logical volumes selected from said plurality of terminal logical volumes without passing through said first communications network whose transfer rate is slower than that of said second communications network; and setting a dedicated boot path for each of said one or more information processing terminals respectively corresponding to said one or more terminal volumes, wherein the boot paths are for accessing said copied OS image data via said second communications network. | CROSS-REFERENCE TO PRIOR APPLICATION This application relates to and claims priority from Japanese Patent Application No. 2004-103263, filed on Mar. 31, 2004 the entire disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for providing an OS image to an information processing terminal via a communications network. 2. Description of the Related Art For example, a technique in which a new OS (operating system) is produced in a plurality of installation destination computers from a new OS kernel and various types of drivers accommodated in an installation server, and the plurality of installation destination computers are restarted with the new OS thus produced, is disclosed in Japanese Patent Application Laid-Open No. 10-133860. SUMMARY OF THE INVENTION A technique in which an image (hereafter referred to as an “OS image”) of the storage region in which the OS is installed is itself stored by the first information processing terminal instead of an OS kernel, and this first information processing terminal distributes this OS image to one or a plurality of second information processing terminals via an LAN, is conceivable. In such a case, however, a large burden is placed on the LAN, and a considerable amount of time is required in order to complete the provision of the OS image. This applies to an even greater extent as the number of destinations to which OS images are provided increases. Accordingly, it is an object of the present invention to provide a deployment technique that allows the rapid provision of OS images to OS image provision destinations. Other objects of the present invention will become clear from the following description. The deployment machine of the present invention is a machine that prepares a plurality of OS images that are respectively used in a plurality of information processing terminals. This deployment machine is connected to a first communications network and a second communications network to which a plurality of information processing terminals and one or more storage systems are connected. This deployment machine comprises a volume preparation part, an OS image copying part, and a boot path setting part. The abovementioned volume preparation part causes the one or more storage systems to prepare a plurality of logical volumes for terminal use respectively corresponding to the abovementioned plurality of information processing terminals inside the abovementioned one or more storage systems. The abovementioned OS image copying part causes the abovementioned one or more storage systems to copy the OS image data stored in the logical volumes into each of the abovementioned one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the first communications network, which has a slower transfer rate than the abovementioned second communications network. The boot path setting part is a part which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; this part sets boot paths for accessing the abovementioned copied OS image data via the abovementioned second communications network. Here, for example, the first communications network is an LAN. Furthermore, for example, the second communications network is an SAN. In other words, for example, the second communications network is a communications network which has a faster data transfer rate than the first communications network. Furthermore, the plurality of terminal logical volumes may be prepared inside a single storage system, or may be prepared in two or more storage systems. In a first embodiment of the deployment machine of the present invention, the abovementioned boot path setting part executes the processing of (1) or (2) below. (1) One or more boot path names respectively corresponding to the abovementioned one or more information processing terminals are respectively transmitted to the abovementioned one or more information processing terminals via the abovementioned first communications network. (2) In cases where access path names for the abovementioned terminal logical volumes are defined inside the abovementioned one or more storage systems, the abovementioned access path names are changed to boot path names that are set beforehand for the information processing terminals corresponding to the abovementioned terminal logical volumes. In a second embodiment of the deployment machine of the present invention, in a case where the deployment machine transmits data via the abovementioned first communications network to an information processing terminal selected from the abovementioned one or more information processing terminals, if the power supply of the abovementioned selected information processing terminal is in an “off” state, the deployment machine transmits the abovementioned data to the abovementioned selected information processing terminal via the abovementioned first communications network after turning on the power supply of the abovementioned selected information processing terminal. In a third embodiment of the deployment machine of the present invention, the abovementioned OS image data copying part executes the processing of (1) or (2) below. (1) Two or more terminal logical volumes selected from the abovementioned plurality of terminal logical volumes are formed into a pair with each other, the OS image data inside the abovementioned logical volumes is read out via the abovementioned second communications network, and the abovementioned read-out OS image data is written all at one time via the second communication network into the two or more terminal logical volumes that are formed into a pair with each other. (2) The abovementioned logical volume that stores OS image data and the abovementioned one or more selected terminal logical volumes are formed into a pair, and the abovementioned one or more storage systems are controlled so that the OS image data stored in the abovementioned OS image volume is copied all at one time into the abovementioned one or more terminal logical volumes. Furthermore, for example, the processing of (1) is performed in cases where the OS image data is in a file format, and the abovementioned logical volume can be accessed by the deployment machine, but cannot be accessed by the information processing terminals. On the other hand, for example, the processing of (2) is performed in cases where the OS image itself is stored in one of the abovementioned logical volumes. In a fourth embodiment of the deployment machine of the present invention, the deployment machine further comprises an information setting part. This information setting part sets unique setting information that is to be set in the information processing terminals in cases where the information processing terminals start the OS, this information being information that is contained in terminal information in a terminal control table in which a plurality of sets of terminal information respectively corresponding to the abovementioned plurality of information processing terminals, in each of the abovementioned one or more information processing terminals. In a fifth embodiment of the deployment machine of the present invention, the abovementioned information setting part in the abovementioned fourth embodiment executes the processing of (1) or (2) below. (1) The abovementioned acquired unique setting information is written into the terminal logical volume of the information processing terminal in which the abovementioned acquired specific information is to be set via the abovementioned second communications network. (2) Information or a computer program that is used to set the abovementioned acquired unique setting information is transmitted to the information processing terminal in which the abovementioned acquired unique setting information is to be set via the abovementioned first communications network. In a sixth embodiment of the deployment machine of the present invention, the abovementioned volume preparation part acquires the OS image data size and one or more different data sizes respectively corresponding to one or more different types of data stored in the terminal logical volume of the information processing terminal selected from the abovementioned plurality of information processing terminals, and prepares a logical volume which has a storage capacity that is equal to or greater than the total of the acquired OS image data size and the abovementioned one ore more different data sizes as the terminal logical volume of the abovementioned selected information processing terminal. The abovementioned respective parts described for the first through sixth embodiments of the deployment machine of the present invention can be realized by means of hardware (e.g., electrical circuits or electronic circuits), computer programs or a combination of both hardware and computer programs. The method of the present invention is a method for preparing a plurality of OS images that are respectively used in a plurality of information processing terminals. This method has first through third steps. In the first step, one or more storage systems connected to a first communications network and a second communications network are caused to prepare a plurality of terminal logical volumes respectively corresponding to the plurality of information processing terminals connected to the first communications network and the second communications network in one or more storage systems. In the second step, the one or more storage systems are caused to copy the OS image data stored in the logical volumes inside the one or more storage systems is copied into each of the one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the abovementioned first communications network which has a slower transfer rate than the abovementioned second communications network. The third step is a step which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; in this step, boot paths are set which are used to access the abovementioned copied OS image data via the abovementioned second communications network. The computer program of the present invention is a computer program which is used to prepare a plurality of OS images that are respectively used by a plurality of information processing terminals. As a result of being read into a computer, this computer program causes the [abovementioned] first through third steps to be executed by this computer. In the first step, one or more storage systems connected to a first communications network and a second communications network are caused to prepare a plurality of terminal logical volumes respectively corresponding to the plurality of information processing terminals connected to the first communications network and the second communications network in the one or more storage systems. In the second step, the one or more storage systems are caused to copy the OS image data stored in the logical volumes inside the one or more storage systems into each of the one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the first communications network whose transfer rate is slower than that of the second communications network. The third step is a step which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; in this step, boot paths are set which are used to access the abovementioned copied OS image data via the abovementioned second communications network. In the present invention, OS images can be quickly provided to OS image provision destinations. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an example of the overall construction of a deployment system constituting one embodiment of the present invention; FIG. 2 shows one example of the server control table 10; FIG. 3 shows one example of the OS image table 20; FIG. 4 shows one example of the flow of OS image distribution in a deployment system constituting one embodiment of the present invention; FIG. 5 shows one example of the flow of OS image distribution in a deployment system constituting one embodiment of the present invention; FIG. 6 is a diagram which is used to explain the boot path setting method; FIG. 7 shows one example of the flow of the processing that is performed in cases where an OS image file is read out; and FIG. 8 shows the flow of the OS image copying processing in a fourth embodiment. DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the attached figures. FIG. 1 shows an example of the overall construction of a deployment system constituting one embodiment of the present invention. A deployment machine 1, a plurality of OS image provision destination servers (hereafter referred to simply as “servers”) (three servers in the present embodiment) 31A through 31C, and a storage system pool 44 consisting of one or more storage systems 43, are connected to a first communications network (e.g., an LAN) 27. Furthermore, the deployment machine 1, plurality of serves 31A through 31C and storage system 44 are also connected to a second communications network (e.g., an SAN (Storage Area Network)) 41. The second communications network 41 is a communications network that is capable of higher-speed data communications than the first communications network 27. For example, the deployment machine 1 is an information processing device such as a personal computer or the like. The deployment machine 1 comprises a first communications interface 3 for the first communications network 27, a second communications interface 7 for the second communications network 41, and a machine main body 5. The machine main body 5 is connected to the first communications interface 3 and second communications interface 7, and comprises (for example) a deployment processor (e.g., a CPU) 73 and a deployment storage part 72. The information processing device performs function as a deployment machine 1 by virtue of an arrangement in which deployment software 6 stored in the deployment storage part 72 is read into the deployment processor 73. For example, the deployment software 6 is a type of application software that operates in the OS (not shown in the figures) of the deployment machine 1 (software that is booted from a hard disk inside the machine 1 or a specified logical volume inside the storage system 43), and comprises a storage control part 11 and a parameter setting part 19. The storage system control part 11 performs control of the storage system 43 from the first communications interface 3 via the first communications network 27 (or from the second communications interface 7 via the second communications network 41). In concrete terms, for example, the storage system control part 11 transmits multiplex pair commands that form two or more logical volumes selected from a plurality of logical volumes into groups (in other words, pairs or multiple pairs) to the storage system 43, or transmits pair forming commands that form a first logical volume and a second logical volume into a pair and copies the data inside the first logical volume into the second logical volume to the storage system 43. Furthermore, as will be described later, the term “logical volume” refers to a logical storage device disposed in a plurality of disk type storage devices 77 inside the storage system 43. The parameter setting part 19 executes server-specific setting processing that is used to set unique setting information relating to the OS image of the server into each of the plurality of servers 31A through 31C. For example, the term “server-specific setting processing” refers to processing that includes both the processing of (1) and the processing of (2) described below. (1) Processing which is devised so that unique setting information for use by the server (e.g., specific parameters or an individual starting execution script described later) is transmitted to a server selected from the plurality of servers 31A through 31C (e.g., the server 31A, hereafter referred to as the “target server 31A”), or unique setting information 32 for used by the server is registered in the logical volume 49 used by the target server 31A, and this unique setting information 32 is provided to and set in the target server 31A as a result of the unique setting information 32 in the logical volume 49 being read out to the target server 31A. (2) Processing in which the server boot path 91 is transmitted to the target server 31A. The parameter setting part 19 comprises an individual script copying part 21, a boot path setting part 25 and a server control part 23. The individual script copying part 21 acquires unique setting information for the respective servers (e.g., specific parameters or individual starting execution script) from a specified storage region in the deployment machine 1 or storage system 43 (e.g., a server control table 10 described later), and writes this information into a logical volume used for the server (this unique setting information may be transmitted to the storage system 43 so as to be copied into this logical volume used for the server; as a result, the unique setting information may be copied into the logical volume used for the server). The boot path setting part 25 performs processing that sets a boot path 91 specific to the target server 31A in this target server 31A via the first communications interface 3. In concrete terms, for example, the boot path setting part 25 performs processing that sets a boot path 91 that is specific to the target server 31A in the firmware 90 of this target server 31A by rewriting all or part of the firmware 90 that is stored in a specified storage region inside the target server 31A (e.g., a storage region in a flash ROM). Furthermore, for example, a method in which the content of the path defined inside the storage system 43 (the content of the path between the server and the logical volume) is altered may be used instead of this boot path setting method. In concrete terms, for example, the abovementioned storage system control part 11 may acquire the boot path defined inside the target server 31A from a specified storage region (e.g., the server storage part 76 inside the target server 31A or the server control table 10 inside the storage system 43), and may alter the content of the path defined inside the storage system 43 (the content of the path between the server and the logical volume) on the basis of this acquired boot path (e.g., may alter the content of the path defined inside the storage control device 45 to a content which is the same as that of the acquired boot path). The server control part 23 controls the respective servers 31A through 31C via the first communications interface 3. In concrete terms, for example, the server control part 23 transmits commands that are used to execute rebooting to the target server, or transmits power supply control commands (e.g., commands that are used to turn the power supply off (or to execute a power saving mode) and/or commands that are used to turn the power supply on (e.g., magic packets according to a Wake On LAN technique)). As a result, the target server executes rebooting in accordance with the content of the received command, or executes specified OS starting processing (e.g., processing that reads out various types of data from the logical volume in accordance with the boot pat defined by the deployment machine 1) by turning the power supply off (or executing a power saving mode) and/or turning the power supply on. The above has been a description of the deployment machine 1. Furthermore, the deployment machine 1 can control the storage device 43 (or another storage device 43A), set server-specific booth paths for the for the respective servers 31A through 31C, and transmit data unrelated to the deployment of the OS to the servers 31A through 31C or storage system 43, via the first communications network 27; however, it is not necessary that all of these operations be performed via the same network path. For example, in cases where the boot path setting part 25 sets the boot path for the target server 31A, this may be set via the first communications interface (e.g., LAN interface) 98 located in the communications auxiliary device 60 of the target server 31A. Next, the respective servers 31A through 31C will be described. Each of the plurality of servers 31A through 31C reads out and starts the OS image from the logical volume assigned to this server by performing booting according to the boot path stored in a specified storage region of the server itself in response to a specified command (e.g., a reboot execution command) from the deployment machine 1. The first server 31A will be described as a typical example of the plurality of servers 31A through 31C. The first server 31A comprises a first communications interface (e.g., an LAN card corresponding to a Wake On LAN) 29 for the first communications network 27, a communications auxiliary device 60, a second communications interface 37 for the second communications network 41, and a server main body 33. For example, the communications auxiliary device 60 may be an externally attached device (e.g., an LAN card), or may be attached directly to the mother board of the first server 31A. The communications auxiliary device 60 comprises another first communications interface (e.g., an LAN controller corresponding to a Wake On LAN) 98 for the first communications network 27. For example, the communications auxiliary device 60 can control the power supply of the server main body 33 by receiving power supply control commands (e.g., commands that are used to turn the power supply off (or to execute a power saving mode) and/or commands used to turn the power supply on (e.g., magic packets according to the Wake On LAN technique)) from the server control part 23 of the deployment machine 1. Furthermore, for example, the communications auxiliary device 60 can perform at least one function of information acquisition, setting or control for the first server 31A. In concrete terms, for example, the communications auxiliary device 60 can acquire server information recorded in the server control table 10 described later (e.g., server discriminating information, unique setting information and the like), and set parameters in the first server 31A (e.g., set the boot path 91 in the firmware 90), from a remote location. The server main body 33 is connected to the first communications interface 29, the communications auxiliary device 60 and the second communications interface 37. For example, the server main body 33 comprises a server processor 74 (e.g., a CPU), and a server storage part 76. The server storage part 76 includes a memory (e.g., a RAM or ROM (for instance, a flash ROM)) or a hard disk, or both. For example, unique setting information received from the individual script copying part 21 of the deployment machine 1 is registered in the server storage part 76. Furthermore, for example, firmware (e.g., BIOS) 90 which has the OS boot path name 91 of the server 31A, and an OS image acquisition part 35, are stored in the server storage part 76. The OS image acquisition part 35 is a computer program, e.g., a bootstrap loader, which executes booting in accordance with the boot path 91 registered in the server storage part 76. The OS image acquisition part 35 may be built into the firmware, or may exist separately from the firmware. For instance, the server processor 74 reads out and starts the OS image inside the first server 31A from the first server volume 49 by reading in the OS image acquisition part 35 stored in the server storage part 76 (or memory installed in the second communications interface 37). Next, the storage system 43 and other storage system 43A will be described. Furthermore, since the storage system 43 and other storage system 43A have substantially the same construction, the storage system 43 will be described as an example. For instance, the storage system 43 is an RAID (Redundant Array of Independent Inexpensive Disks) system which is constructed by disposing numerous disk type storage devices (physical disks) 77 in the form of an array. The storage system 43 comprises a plurality of logical volumes disposed in one or more disk type storage devices 77, and a storage control device 45 which controls communications between the deployment machine 1 and plurality of servers 31A through 31C (hereafter referred to collectively as a “higher device”) and the abovementioned plurality of logical volumes. For example, the plurality of logical volumes include a deployment volume 47 which is assigned to the deployment machine 27, a first server volume 49 which is assigned to the first server 31A, a second server volume 51 which is assigned to the second server 31B, and a third server volume 53 which is assigned to the third server 31C. Logical volume IDs (e.g., numbers) which are used for immediate specification of the logical volumes are assigned to the respective logical volumes. In FIG. 1, the logical volume ID for each logical volume is shown in [Japanese style] brackets [indicated as quotation marks in English translation]. Specifically, it is seen in FIG. 1 that the logical volume ID for the first server logical volume is “2”. The deployment volume 47 is a logical volume that can be referred to by the deployment machine 1. A server control table 10, OS image data 20 and one or more OS image files 57A and 57B are stored in this deployment volume 47. The server control table 10 is used to control the deployment machine 1 and the respective servers 31A and 31B. In concrete terms, for example, as is shown in FIG. 2, this table contains server information corresponding to the deployment machine 1 and to each of the plurality of servers 31A through 31C. For instance, the server information for the respective servers 31A through 31C (and the deployment machine 1) contains server discriminating information (e.g., device name and/or MAC address) for the server in question), the OS image name of the OS image file corresponding to this server, unique setting information set in this server, ID of the logical volume to which this server can refer, and boot path used to start this server. For instance, the unique setting information for each server includes specific parameters such as IP address, gateway address and the like, and is set in the server by a method such as reading the OS image in which this unique setting information is incorporated into the server, or reading the information out by means of the deployment machine 1, and transmitting the information to the server via the first communications network 27. Furthermore, the unique setting information registered in the server control table 10 may be the starting execution script itself that is created so as to set the specific parameters, or may be information (pointers) that indicates the location of the specific parameters or starting execution script. For instance, server discriminating information, OS image names and unique setting information are registered beforehand in the server control table 10, and when a server volume is prepared, the ID of this server volume is additionally registered. Furthermore, other information such as the server volume ID or the like may also be registered beforehand (in other words, a completed server control table 10 may be prepared beforehand). Furthermore, in cases where one or more other storage systems 43A are connected inside the storage system table 44, information relating to servers (not shown in the figures) that read out OS image files from the logical volumes 160 inside these one or more other storage systems 43A may also be registered in this server control table 10. Furthermore, information relating to servers (not shown in the figures) that acquire OS image files via the first communications network 27 rather than the second communications network 41 may also be registered in this server control table 10. In other words, information relating to servers that acquire OS image files via the second communications network 41 and information relating to servers that acquire OS image files via the first communications network 27 may be mixed in the server control table 10. The OS image table 20 is used to control one or more OS image files prepared inside the storage system 43 (e.g., inside the deployment volume 47). For example, as is shown in FIG. 3, one or more sets of OS image information respectively corresponding to one or more OS image files are contained in the OS image table 20. For instance, the OS image information for each OS image file includes the OS image name, the name of the OS image file, and the content and ID relating to the OS image file. Furthermore, for example, it is sufficient even if only the OS image name (or other OS image discriminating information) and the OS image file name (or other information specifying the location of the OS image file) are contained in the OS image information. The corresponding OS image itself and one or more attributes relating to the OS image (e.g., the OS image data size or the like) are noted in each of the one or more OS image files 57A and 57B. For example, the storage control device 45 comprises a first I/F 99 which is in interface for the first communications network 27, a second I/F 92 which is an interface for the second communications network 41, one or more processors (e.g., MPUs (Micro-Processing Units) or CPUs (Central Processing Units)) 95 which execute processing or the like in accordance with various types of commands from the higher device, a memory 94 which has a buffer region or the like in which data received from the higher device is temporarily stored, and a disk I/F 93 which is an interface for the disk type storage devices 77. For example, in response to various types of commands from the deployment machine 1, the storage control device 45 (e.g., the processor 95) constructs a new logical volume in a disk type storage device, or places the deployment volume 47 and one or more server volumes (e.g., the two server volumes 49 and 51) in a pair state, copies the OS image file inside the deployment volume 47 (e.g., the OS image file 57A) into the one or more server volumes, and dissolves the abovementioned pair state. The above has been a description of the overall construction of the deployment system of the present embodiment. Below, an example of the flow up to the point where the OS image is distributed to the respective servers in this system will be described with reference to FIG. 4 and following figures. The deployment machine 1 executes various types of processing such as initial setting and the like (step S1), and starts its own OS. Furthermore, in cases where the machine 1 receives a start command for the deployment software (hereafter abbreviated to “DS”) 6 from the user, the DS 6 is read into the CPU and prepared above the OS. The DS 6 receives a multiplex mirror instruction for the user. When the DS 6 receives a multiplex mirror instruction from the user, the storage system control part 11 of the DS 6 executes multiplex mirror instruction transmission processing. In concrete terms, the storage system control part 11 of the DS 6 first indicates the deployment volume ID “1” to the storage system 43 via the first communications network 27 (or second communications network 41), accesses the deployment volume 47, and refers to the server control table 10, OS image table 20 and respective OS image files 57A and 57B (S2A). Then, the storage system control part 11 instructs the storage system 43 to construct the server logical volumes 49, 51 and 53 for each server on the basis of various types of attribute information for the servers (e.g., the size of the OS image data recorded in the OS image file corresponding to the OS image name of the server, the data size of the unique setting information for the server and the like) (S2B). As a result, respective server logical volumes 49, 51 and 53 based on the attribute information for each server are newly constructed in the disk type storage device(s) 77 by the storage control device 45 of the storage system 43 (S2C). Furthermore, for example, the logical volume IDs of the respective server logical volumes 49, 51 and 53 thus constructed may be IDs that are provided to the DS 6, or IDs that are provided to the processor 95 of the storage control device 45. Furthermore, for example, the logical volume IDs thus provided are written into places corresponding to the respective servers in the server control table 10 by the DS 6 via the first I/F 99 or second I/F 92 of the storage control device 45. Moreover, for example, in cases where the storage system control part 11 constructs a first server logical volume 49 corresponding to the first server 31A, the storage system control part 11 constructs a server logical volume which has a storage capacity that is greater than the total of the data size of the OS image data contained in the attribute information corresponding to this first server 31A and the data size of the specific setting data and the like. Furthermore, the attribute information for each server can be stored in a specified storage region in the deployment machine 1 or storage system 43 (e.g., the server control table 10 shown for example in FIG. 2). Next, on the basis of the information recorded in the server control table 10 and OS image table 20, the storage system control part 11 of the DS 6 selects two or more (e.g., two) server volumes 49 and 51 in which the same OS image file is stored from the plurality of server volumes 49, 51 and 53, and forms the volumes into a pair with each other (S3). In other words, the storage system control part 11 of the DS 6 forms the abovementioned two selected server volumes into a mirror volume. Next, on the basis of the server control table 10 and OS image table 20, the storage system control part 11 of the DS 6 selects the OS image file 57A stored in the two server volumes 49 and 51 (formed into a pair) from the one or more OS image files 57A and 57B inside the deployment volume 47. Then, the storage system control part 11 of the DS 6 successively copies the selected OS image file 57A as an image in block units into the pair of the two server volumes 49 and 51 all at one time (S4). In concrete terms, for example, the storage system control part 11 of the DS 6 reads out the selected OS image file 57A via the second communications network 41, and transmits the read-out OS image file 57A via the second communications network to the mirror volume consisting of the two server volumes 49 and 51 that were formed into a pair. As a result, the transmitted OS image file 57A is written all at one time into the two server logical volumes 49 and 51 constituting the abovementioned pair by the storage control device 45. The storage system control part 11 of the DS 6 repeats the processing of S3 and S4 until this processing is completed for all of the servers 31A through 31C (N in S5, S6). The storage system control part 11 may perform the processing of S3 and S4 successively for each of the respective OS images, or may perform this processing in parallel. Furthermore, in the example described above, the number of server volumes formed into a pair with each other is two; however, in cases where the number of server volumes in which the same OS image file is stored is three or greater, these three or more server volumes may be formed into pairs with each other, and the same OS image file may be copied all at one time into these three or more server volumes. When the processing of S3 and S4 is completed for all of the servers 31A through 31C (Y in S5), OS image files corresponding to these servers are prepared in the respective server volumes 49, 51 and 53 corresponding to the respective servers 31A through 31C. At this point in time, the OS image files themselves (of the respective servers) are not in a state that is suited to the servers (in other words, if the unique setting information of the servers is not set inside the server volumes or inside the servers, OS starting that is suited to the servers cannot be performed). After Y is obtained in S5, the storage system control part 11 of the DS 6 transmits a multiplex mirror split instruction to the storage system 43, so that the pair state of the abovementioned two server volumes 49 and 51 is dissolved (S7). Following S7, the DS 6 executes processing that is used to input the unique setting information for each server into the respective servers. In concrete terms, for example, as is shown in FIG. 5, the individual script copying part 21 in the parameter setting part 19 of the DS 6 refers to the server control table 10, and transmits a read request to read the respective server volume IDs recorded in this table 10, and the corresponding unique setting information (e.g., specific parameters or starting execution script), to the storage system 43 via the second communications network 41 (or first communications network 27) (S8). The storage control device 45 acquires the server volume ID and unique setting information according to the read request from the server control table 10, and transmits this information to the deployment machine 1 via the second communications network 41 (or first communications network 27) (S9). As a result, the individual script copying part 21 acquires the server volume ID and unique setting information for each server (S10). Next, the individual script copying part 21 transmits a write request to write the unique setting information corresponding to the respective acquired server volume IDs (e.g., “2”) into the respective server volumes having this ID to the storage system 43 via the second communications network 41 (S11). The storage control device 45 writes the unique setting information contained in the write request into the server volume according to the write request (e.g., the first server volume 49) (S12). As a result, the unique setting information corresponding to the respective servers is registered in the server logical volumes of these servers. Next, for example, the boot path setting part 25 in the parameter setting part 19 of the DS 6 sets the boot path of the OS image file of the server for each of the plurality of servers 31A through 31C (S13). For example, the following two methods are conceivable as methods for setting the boot path. FIG. 6 is a diagram which is used to illustrate the boot path setting method. In concrete terms, FIG. 6(A) is an explanatory diagram of a first boot path setting method, and FIG. 6(B) is an explanatory diagram of a second boot path setting method. Below, these methods will be described in order. Furthermore, in the following description, a case in which the boot path of the first server 31A is set will be taken as an example. (1) First Boot Path Setting Method The boot path setting part 25 reads out the new boot path name of the first server 31A recorded in the server control table 10, or sends an instruction to the user via the DS 6 (S13A). Furthermore, for example, this new boot path name may be a name recorded beforehand by the system manager of the storage system 43 using the DS 6, or may be a name that is written by the storage system control part 11 of the DS 6 following the copying processing of S4. The boot path setting part 25 transmits the acquired boot path name of the first server 31A to the communications auxiliary device 60 of the first server 31A via the first communications network 27 (S13B). As a result, the communications auxiliary device 60 rewrites the boot path name 91 used by the firmware 90 inside the first server 31A as the received new boot path name (S13C). Furthermore, in this first boot path setting method, in cases where the power supply of the server prior to the setting of the boot path is in an “off” state, the boot path setting part 25 may perform the processing of S13B after turning the power supply of the server main body 33 on by a remote operation using the server control part 23 (e.g., by transmitting a magic packet). Moreover, if the system is arranged so that the server can receive a new boot path and set this boot path inside its own apparatus even if the power supply of the server main body 33 is in an “off” state, it is not necessary to turn on the power supply by a remote operation. (2) Second Boot Path Setting Method For example, as is shown in FIG. 6(B), an access path name is defined beforehand for each of a plurality of logical volumes inside the storage system 43 (e.g., in the memory 94 of the storage control device 45). In concrete terms, for example, a volume control table 180 in which respective access path names corresponding to respective logical volumes (combinations of physical disks) are recorded is provided inside the storage system 43. Furthermore, the respective alphabetic characters “{A, B, F, G}”, which constitute one example of a combination of physical disks, are IDs that are assigned to the physical disks. Moreover, the access path names can be constructed in various ways; for example, a construction including the ID of the communications port 191 in the storage system 43 that is connected to the second communications network 41, the target ID belonging to this communications port ID, the LUN (Logical Unit Number) belonging to this target ID and the logical volume ID belonging to this LUN may be used. The boot path setting part 25 acquires the boot path name (e.g., information having a construction similar to that of the abovementioned access path name) 91 corresponding to the first server 31A (S13D). The acquired boot path name 91 may be a name that is received from the first server 31A, or may be a name that is recorded beforehand in the server control table 10. Next, the storage system control part 11 of the DS 6 accesses the storage system 43, and performs processing that changes the access path name including the logical volume ID of the first server volume 49 (among the plurality of access path names recorded in the volume control table 180) to the boot path name 91 acquired in S13D (S13E). As a result, even if the first server 31A subsequently accesses the storage system 43 in accordance with the preset boot path name 91, the first server 31A can access the first server volume 49, and can read out the OS image that has been copied into this volume 49. When the boot path setting part 25 has set a new server boot path for each server, the processing is ended. Furthermore, after the boot path setting part 25 has set the new boot paths, the server control part 23 transmits start commands to the respective servers 31A through 31C (e.g., transmits these commands all at one time); as a result, the system may be set so that booting is executed according to the new boot paths in the respective servers 31A through 31C, and so that the plurality of OS image files respectively corresponding to the plurality of servers 31A through 31C are provided to the plurality of servers 31A through 31C all at one time. Below, the flow of the processing that is performed when the servers read out OS image files will be described using the first server 31A (among the plurality of servers 31A through 31C) as an example. FIG. 7 shows the flow of the processing that is performed in a case where the first server 31A reads out the OS image file 57A. In a case where the first server 31A starts after a new boot path has been set, the OS image acquisition part 35 of this server 31A accesses the logical volume indicated by the boot path name 91 set in the server storage part 76 (S21). Since the boot path name of the first server 31A is set by the method described with reference to FIG. 6, the OS image acquisition part 35 accesses the first server volume 49 as a result of S21. The OS image acquisition part 35 reads out the OS image file 57A and the unique setting information 32 from the first server volume 49 (S22), so that the OS is started by the server. For example, the unique setting information (e. g., specific parameters such as the IP address, gateway address and the like) is set by the firmware 90 (e.g., BIOS). The above has been a description of the flow up to the point where the OS image is distributed to the respective servers. Furthermore, this flow is the flow of the processing used to distribute the OS image to all of a plurality of servers 31A through 31C; however, it would also of course be possible to apply this flow in cases where the OS image is distributed to only a single server. In the embodiment described above, the system does not depend on the band of the first communications network (e.g., an LAN), so that the OS image can be distributed to a plurality of servers in a shorter time than in a conventional technique. As was described above, the above embodiment is merely a single embodiment of the present invention; in this embodiment, a number of modifications such as those described below are conceivable. For example, in a first modification, the deployment machine 1 may read OS image files corresponding to the respective servers (e.g., compressed files) from a logical volume (subsequently performing (for example) thawing and freezing processing), and may write these OS image files into the server logical volume via the second communications network 41. Furthermore, the storage system control part 11 of the DS 6 may copy the OS image file inside the deployment volume 47 of the storage system 43 into the logical volume 160 inside another storage system 43A. In a second modification, there may be an on-line state in which higher devices corresponding to logical volumes are in a state that allows access, and an off-line state in which even higher devices corresponding to the logical volumes are in a state that does not allow access, in the respective logical volumes. For example, the question of whether the respective logical volumes are in an on-line state or an off-line state can be determined according to whether volume state bits respectively corresponding to the plurality of logical volumes are “1” or “0”. The respective volume state bits may be recorded in a memory inside the storage control device 45. The storage control device 45 may perform the abovementioned copying processing on the basis of the server control table 10 after preparing a plurality of server volumes and switching the respective server volumes to the [abovementioned] off-line state all at one time (i.e., after switching the volumes to a state in which the volumes cannot be accessed from any higher device). Subsequently, the storage control device 45 can dissolve the abovementioned pair state, either on its own account or in response to a “split” command from the DS 6. In this case, the storage control device 45 may switch the server logical volume into which the OS image file has been copied from the off-line state to the on-line state (e.g., may alter the volume state bit from “0” to “1”) at a specified timing (e.g., immediately after the dissolution of the pair state). In a third modification, at least the server control table 10 (among the server control table 10 and the OS image table 20) may be stored outside the storage system 43 rather than inside the deployment volume 47, e.g., inside the deployment storage part 72 of the deployment machine 1 (for example, in a data storage volume used by the DS 6 in an internally installed hard disk). In a fourth modification, the OS image may be prepared as a volume rather than in a file format. In this case, for example, the copying of the OS image may be performed by the processing flow shown n FIG. 8. Specifically, the storage system control part 11 of the DS 6 selects the OS image volume in which the OS image that is the object of copying is stored from one or more OS image volumes (logical volumes in which OS images are present) 200 inside the storage system 43 (S51). Furthermore, the storage system control part 11 selects one or more (e.g., two) server volumes 49 and 51 that are the copying destinations of the OS image that is the object of copying from the plurality of server volumes 49, 51 and 53 (S52). Next, the storage system control part 11 forms the OS image volume 200 selected in S51 and the one or more server volumes 49 and 51 selected in S52 into pairs (S53). Then, the storage system control part 11 transmits a synchronizing command to the storage system 43 (S54). As a result, the OS image inside the OS image volume 200 is copied all at one time by the storage control device 45 into the one or more server volumes 49 and 51 that form pairs with this OS image volume 200. After copying is completed, the storage system control part 11 of the DS 6 dissolves the pairs formed in S53 (S55). Furthermore, for example, in S53, it is not absolutely necessary that pairs may be formed between two volumes; multiple pairs may also be formed among three or more volumes. In this case, since the same data is stored in corresponding address blocks of the three or more volumes, the OS image can be written into the three or more server volumes formed into pairs in a time that is substantially equal to a single OS image writing time. Embodiments and modifications of the present invention have been described above. However, these are merely examples used to illustrate the present invention; the scope of the present invention is not limited to these embodiments and modifications alone. The present invention may be embodied in various other forms. For example, the present invention is not limited to the above description as long as a correspondence is established between the boot path names set for the servers and the access path names of the server logical volumes. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to a technique for providing an OS image to an information processing terminal via a communications network. 2. Description of the Related Art For example, a technique in which a new OS (operating system) is produced in a plurality of installation destination computers from a new OS kernel and various types of drivers accommodated in an installation server, and the plurality of installation destination computers are restarted with the new OS thus produced, is disclosed in Japanese Patent Application Laid-Open No. 10-133860. | <SOH> SUMMARY OF THE INVENTION <EOH>A technique in which an image (hereafter referred to as an “OS image”) of the storage region in which the OS is installed is itself stored by the first information processing terminal instead of an OS kernel, and this first information processing terminal distributes this OS image to one or a plurality of second information processing terminals via an LAN, is conceivable. In such a case, however, a large burden is placed on the LAN, and a considerable amount of time is required in order to complete the provision of the OS image. This applies to an even greater extent as the number of destinations to which OS images are provided increases. Accordingly, it is an object of the present invention to provide a deployment technique that allows the rapid provision of OS images to OS image provision destinations. Other objects of the present invention will become clear from the following description. The deployment machine of the present invention is a machine that prepares a plurality of OS images that are respectively used in a plurality of information processing terminals. This deployment machine is connected to a first communications network and a second communications network to which a plurality of information processing terminals and one or more storage systems are connected. This deployment machine comprises a volume preparation part, an OS image copying part, and a boot path setting part. The abovementioned volume preparation part causes the one or more storage systems to prepare a plurality of logical volumes for terminal use respectively corresponding to the abovementioned plurality of information processing terminals inside the abovementioned one or more storage systems. The abovementioned OS image copying part causes the abovementioned one or more storage systems to copy the OS image data stored in the logical volumes into each of the abovementioned one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the first communications network, which has a slower transfer rate than the abovementioned second communications network. The boot path setting part is a part which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; this part sets boot paths for accessing the abovementioned copied OS image data via the abovementioned second communications network. Here, for example, the first communications network is an LAN. Furthermore, for example, the second communications network is an SAN. In other words, for example, the second communications network is a communications network which has a faster data transfer rate than the first communications network. Furthermore, the plurality of terminal logical volumes may be prepared inside a single storage system, or may be prepared in two or more storage systems. In a first embodiment of the deployment machine of the present invention, the abovementioned boot path setting part executes the processing of (1) or (2) below. (1) One or more boot path names respectively corresponding to the abovementioned one or more information processing terminals are respectively transmitted to the abovementioned one or more information processing terminals via the abovementioned first communications network. (2) In cases where access path names for the abovementioned terminal logical volumes are defined inside the abovementioned one or more storage systems, the abovementioned access path names are changed to boot path names that are set beforehand for the information processing terminals corresponding to the abovementioned terminal logical volumes. In a second embodiment of the deployment machine of the present invention, in a case where the deployment machine transmits data via the abovementioned first communications network to an information processing terminal selected from the abovementioned one or more information processing terminals, if the power supply of the abovementioned selected information processing terminal is in an “off” state, the deployment machine transmits the abovementioned data to the abovementioned selected information processing terminal via the abovementioned first communications network after turning on the power supply of the abovementioned selected information processing terminal. In a third embodiment of the deployment machine of the present invention, the abovementioned OS image data copying part executes the processing of (1) or (2) below. (1) Two or more terminal logical volumes selected from the abovementioned plurality of terminal logical volumes are formed into a pair with each other, the OS image data inside the abovementioned logical volumes is read out via the abovementioned second communications network, and the abovementioned read-out OS image data is written all at one time via the second communication network into the two or more terminal logical volumes that are formed into a pair with each other. (2) The abovementioned logical volume that stores OS image data and the abovementioned one or more selected terminal logical volumes are formed into a pair, and the abovementioned one or more storage systems are controlled so that the OS image data stored in the abovementioned OS image volume is copied all at one time into the abovementioned one or more terminal logical volumes. Furthermore, for example, the processing of (1) is performed in cases where the OS image data is in a file format, and the abovementioned logical volume can be accessed by the deployment machine, but cannot be accessed by the information processing terminals. On the other hand, for example, the processing of (2) is performed in cases where the OS image itself is stored in one of the abovementioned logical volumes. In a fourth embodiment of the deployment machine of the present invention, the deployment machine further comprises an information setting part. This information setting part sets unique setting information that is to be set in the information processing terminals in cases where the information processing terminals start the OS, this information being information that is contained in terminal information in a terminal control table in which a plurality of sets of terminal information respectively corresponding to the abovementioned plurality of information processing terminals, in each of the abovementioned one or more information processing terminals. In a fifth embodiment of the deployment machine of the present invention, the abovementioned information setting part in the abovementioned fourth embodiment executes the processing of (1) or (2) below. (1) The abovementioned acquired unique setting information is written into the terminal logical volume of the information processing terminal in which the abovementioned acquired specific information is to be set via the abovementioned second communications network. (2) Information or a computer program that is used to set the abovementioned acquired unique setting information is transmitted to the information processing terminal in which the abovementioned acquired unique setting information is to be set via the abovementioned first communications network. In a sixth embodiment of the deployment machine of the present invention, the abovementioned volume preparation part acquires the OS image data size and one or more different data sizes respectively corresponding to one or more different types of data stored in the terminal logical volume of the information processing terminal selected from the abovementioned plurality of information processing terminals, and prepares a logical volume which has a storage capacity that is equal to or greater than the total of the acquired OS image data size and the abovementioned one ore more different data sizes as the terminal logical volume of the abovementioned selected information processing terminal. The abovementioned respective parts described for the first through sixth embodiments of the deployment machine of the present invention can be realized by means of hardware (e.g., electrical circuits or electronic circuits), computer programs or a combination of both hardware and computer programs. The method of the present invention is a method for preparing a plurality of OS images that are respectively used in a plurality of information processing terminals. This method has first through third steps. In the first step, one or more storage systems connected to a first communications network and a second communications network are caused to prepare a plurality of terminal logical volumes respectively corresponding to the plurality of information processing terminals connected to the first communications network and the second communications network in one or more storage systems. In the second step, the one or more storage systems are caused to copy the OS image data stored in the logical volumes inside the one or more storage systems is copied into each of the one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the abovementioned first communications network which has a slower transfer rate than the abovementioned second communications network. The third step is a step which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; in this step, boot paths are set which are used to access the abovementioned copied OS image data via the abovementioned second communications network. The computer program of the present invention is a computer program which is used to prepare a plurality of OS images that are respectively used by a plurality of information processing terminals. As a result of being read into a computer, this computer program causes the [abovementioned] first through third steps to be executed by this computer. In the first step, one or more storage systems connected to a first communications network and a second communications network are caused to prepare a plurality of terminal logical volumes respectively corresponding to the plurality of information processing terminals connected to the first communications network and the second communications network in the one or more storage systems. In the second step, the one or more storage systems are caused to copy the OS image data stored in the logical volumes inside the one or more storage systems into each of the one or more terminal logical volumes selected from the plurality of terminal logical volumes without passing through the first communications network whose transfer rate is slower than that of the second communications network. The third step is a step which sets a dedicated boot path for each of the one or more information processing terminals respectively corresponding to the abovementioned one or more terminal volumes; in this step, boot paths are set which are used to access the abovementioned copied OS image data via the abovementioned second communications network. In the present invention, OS images can be quickly provided to OS image provision destinations. | 20050125 | 20091103 | 20051006 | 57400.0 | 0 | CHAVIS, JOHN Q | MACHINE AND METHOD FOR DEPLOYMENT OF OS IMAGE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,223 | ACCEPTED | Opinion registering application for a universal pervasive transaction framework | A computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, including a device encoding the content of the transaction input by the user with a key known only to another device, encoding other portions of the transaction with another key known only to a secure transaction server, and sending the encoded content of the transaction and the encoded other portions of the transaction to the secure transaction server to authenticate an identity of the user of the device, wherein the secure transaction server decodes the other portions of the transaction and sends the encoded content of the transaction to the another device to be finally decoded. | 1. A computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, comprising: a first device, where the content of the transaction is input and submitted to a second device; the second device encoding the content of the transaction that is input at the first device with a code key KVsi, sending the content of the transaction that is encoded with the code key KVSi to the first device, the first device generating a first message by further encoding the content of the transaction that is encoded with the code key KVSi with a respective UPTF-SAS key, and the second device generating a second device encoded message by further encoding the content of the transaction that is encoded with the code key KVSi with a respective UPTF-SAS key; a third device receiving the encoded messages of the first and the second device, decoding the received encoded messages to authenticate an identity of the user of the first device, matching the decoded messages to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction that is encoded with the code key KVS to a fourth device; and the fourth device receiving the encoded content of the transaction encoded with the code key KVSi and using the code key KVSi to determine content of the transaction input by the user of the first device. 2. The computer-based system of claim 1, wherein the second device and the fourth device agree on the code key KVsi, or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and wherein the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key KVSi of the second device to decode the content of the transaction that is encoded with the code key KVsi. 3. The computer-based system of claim 1, wherein the second device cannot determine the identity of the user that input the content of the transaction because when the content of the transaction is input at the first device and submitted to the second device, the first device does not transmit user identifying information to the second device, and because in the first message generated by the first device, the identity of the user is encoded by the first device according to a coding technique that can only be decoded by the third device. 4. The computer-based system of claim 1, wherein the third device cannot determine the content of the transaction input by the user but can determine whether a particular user input the content of the transaction at a particular second device, and wherein the fourth device cannot determine the identity of the user that input the content of the transaction since the fourth device cannot determine the first device in which the content of the transaction was input by the user. 5. The computer-based system of claim 4, wherein the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF-SAS keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF-SAS coding keys, and wherein the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. 6. The computer-based system of claim 5, wherein the user is authenticated to operate the first device according at least one biometric feature of the user or a personal identification number. 7. The computer-based system of claim 5, wherein the transaction of the computer system is performed between the first and the second device, the transaction is an opinion registering application, and the content of the transaction is a ballot. 8. The computer-based system of claim 1, wherein there is one or more first device and one or more second device. 9. The computer-based system of claim 1, further comprising a virtual private network located between the second device and the fourth device and another virtual private network located between the third device and the fourth device. 10. A computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, comprising: a first device generating an encoded message, including a user input content portion, according to UPTF; a second device further encoding the user input content portion of the encoded message with a coding key KVSi and generating a second device encoded message corresponding to the transaction according to UPTF; a third device receiving, decoding, and comparing the encoded messages of the first and second device to authenticate an identity of the user of the first device and to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction encoded with the code key KVsi; and a fourth device receiving the encoded content of the transaction encoded with the code key KVSi and using the code key KVSi to determine the content of the transaction input by the user of the first device. 11. The computer-based system of claim 10, wherein coding algorithm used for further encoding the user input content portion of the encoded message with the coding key KVsi is commutative with the algorithm used by the first device to generate the encoded message. 12. The computer-based system of claim of claim 10, wherein the second device message does not include the user input content portion. 13. The computer-based system of claim of claim 10, wherein the second device and the fourth device agree on the code key KVsi, or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and wherein the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key KVSi of the second device to decode the user input content portion of the encoded message encoded with the coding key KVsi. 14. The computer-based system of claim 10, wherein the third device cannot determine the user input content portion of the transaction the user input content portion of the encoded message is encoded with the coding key KVSi, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction because the fourth device only receives the user input content portion of the transaction. 15. The computer-based system of claim 10, wherein the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF coding keys, and wherein the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. 16. The computer-based system of claim 10, wherein the transaction of the computer system is performed between the first and the second device, the transaction is an opinion registering application, and the user input content portion of the transaction is a ballot. 17. The computer-based system of claim 10, wherein there is more than one first device and more than one second device. 18. The computer-based system of claim 10, further comprising a virtual private network located between the second device and the fourth device and another virtual private network located between the third device and the fourth device. 19. A computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, comprising: a first device receiving from a second device a reference number, which relates to a not yet input transaction, the first device generating a first encoded message after the transaction, which is a user input content portion, is input by the user at the first device, such that the first encoded message includes the user input content portion that is encoded with a random code key KV, the first device generating a second encoded message including, which includes the random code key KV and the reference number, and sending the first and second encoded messages to the second device; the second device storing the first encoded message, forwarding the second encoded message to a third device, and generating a third encoded message including the random code key KV and the reference number and not containing the user input content portion; the third device receiving the second and third encoded messages, which do not have the user input content portion, decoding the messages to authenticate an identity of the user and matching content of the second and third decoded messages to authenticate an occurrence of the transaction, and forwarding the code key KV and the reference number to a fourth device; and the fourth device receiving from the second device the first encoded message and the reference number, receiving from the third device the random code key KV and the reference number, and determining from the received information the user input content portion of the transaction input by the user. 20. The computer-based system of claim 19, wherein the first encoded message is stored in a database of the second device and is not sent to the fourth device to be decoded until the third device has verified the identity of the user and the occurrence of the transaction. 21. The computer-based system of claim 19, wherein the third device never receives the user input content portion of the transaction input by the user, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction because the fourth device does not receive identifying information of the user. 22. The computer-based system of claim 19, wherein the computer system performs a transaction between the first and the second device, the transaction is an opinion registering application, and the user input content portion of the transaction is a ballot. 23. The computer-based system of claim 19, wherein there is more than one first device and more than one second device. 24. The computer-based system of claim 19, further comprising a virtual private network located between the second device and the fourth device and another virtual private network located between the third device and the fourth device. 25. The computer-based system of claim 19, wherein the user input content portion of the transaction is encoded whenever sent from the first device to any other device in the computer-based system, wherein the third device never receives the user input content portion of the transaction, and wherein there is an accounting for the transaction input by the user so that errors may be located. 26. A computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, comprising: a device encoding the content of the transaction input by the user with a key known only to another device, encoding other portions of the transaction with another key known only to a secure transaction server, and sending the encoded content of the transaction and the encoded other portions of the transaction to the secure transaction server to authenticate an identity of the user of the device, wherein the secure transaction server decodes the other portions of the transaction and sends the encoded content of the transaction to the another device to be finally decoded. 27. The computer-based system of claim 26, wherein the another device decodes the contents of the transaction without knowledge of the identity of the device, and wherein neither the secure transaction server nor the another device know both the contents of the transaction and the identity of the device. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is related to, and claims the benefit of and priority to, Provisional Application U.S. Ser. No. 60/541,903, Attorney Docket No. 1634.1006P, entitled AN OPINION REGISTERING APPLICATION, by Yannis Labrou, Lusheng Ji, Jesus Molina Terriza, and Jonathan Agre, filed Feb. 6, 2004 in the U.S. Patent and Trademark Office, the contents of which are incorporated herein by reference. This application is related to U.S. Provisional Application No. 60/401,807, filed Aug. 8, 2002, entitled “Methods and Apparatuses for Secure Multi-Party Financial Transactions”, the contents of which are incorporated herein by reference. This application is related to U.S. application Ser. No. 10/458,205, filed Jun. 11, 2003, entitled “Security Framework and Protocol for Universal Pervasive Transaction”, the contents of which are incorporated herein by reference. This application is related to U.S. application Ser. No. 10/628,583, filed Jul. 29, 2003, entitled “Framework and System for Purchasing of Goods and Services”, the contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is related to an opinion registering application in a Universal Pervasive Transaction Framework, an example of which is voting, and more particularly, to an application that requires a transaction to be multi-coded so that the identity of a user and the content of the transaction cannot both be known by any single device, other than the device in which the transaction is input, within or outside of the network. 2. Description of the Related Art Electronic-voting (“e-voting”) applications are well known in the art and have several desirable characteristics such as convenience of voting or opinion registering, non-human computation or tallying of votes, faster processing and voting times, and flexibility. However, e-voting, as with most Internet-type transaction, is prone to security violations, inaccuracy, and integrity issues. E-voting is not like any other electronic transaction. There are two main types of e-voting: polling place e-voting, and remote e-voting. Remote e-voting is the unsupervised use of an Internet voting device to cast a ballot over the Internet using a computer not necessarily owned and operated by election personnel. Authentication of the voter relies on computer security procedures, but includes some form of identity verification that is at least as secure as existing voting procedures. Remote e-voting is highly susceptible to voter fraud. Polling place e-voting is defined as the use of Internet Voting Machines at traditional polling places staffed by election officials who assist in the authentication of voters before ballots are cast. Several cryptography methods have been developed and/or are being used to ensure secrecy and security with regards to e-voting so that e-voting may be reliably used for voting in municipal, regional, or national elections. Essentially, a polling station computer confirms to a voter that a valid vote has been cast, and also provides a receipt. This paper receipt has an encoded code on it derived from a central computer. After the election, the voter can confirm that his/her vote was counted, for example, by checking a particular Web site to make sure that their receipt's sequence corresponds to those that have been posted, or asking an organization that they trust to do the verification. For instance, most polling place e-voting applications involve the following type of security: (1) the voter constructs an “anonymous electronic ballot”; (2) the voter shows adequate proof of identity to an election authority; (3) the election authority “stamps” the ballot after verifying that no other ballot has been stamped for this voter; and (4) the voter anonymously inserts the ballot into an electronic mail box. Current e-voting applications are not secure or reliable. Voters are often required to vote from specific e-voting type voting equipment. Voters are not able to vote wirelessly from a Universal Pervasive Transaction Device, such as a PDA or cell-phone, in a secure manner such that the voting action can be authenticated but without any third party or device knowing the content of the vote of that specific individual. Further, there is no way to ensure that the voting action transaction can transpire without any third party or device knowing the content of the vote of a particular voter. SUMMARY OF THE INVENTION According to an aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, including a first device, where the content of the transaction is input and submitted to a second device, the second device encoding the content of the transaction that is input at the first device with a code key KVsi sending the content of the transaction that is encoded with the code key KVSi to the first device, the first device generating a first message by further encoding the content of the transaction that is encoded with the code key KVSi with a respective UPTF-SAS key, and the second device generating a second device encoded message by further encoding the content of the transaction that is encoded with the code key KVSi with a respective UPTF-SAS key, a third device receiving the encoded messages of the first and the second device, decoding the received encoded messages to authenticate an identity of the user of the first device, matching the decoded messages to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction that is encoded with the code key KVS to a fourth device, and the fourth device receiving the encoded content of the transaction encoded with the code key KVSi and using the code key KVSi to determine content of the transaction input by the user of the first device. According to an aspect of the present invention, the second device and the fourth device agree on the code key KVsi, or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key KVSi of the second device to decode the content of the transaction that is encoded with the code key KVsi. According to an aspect of the present invention, the second device cannot determine the identity of the user that input the content of the transaction because when the content of the transaction is input at the first device and submitted to the second device, the first device does not transmit user identifying information to the second device, and because in the first message generated by the first device, the identity of the user is encoded by the first device according to a coding technique that can only be decoded by the third device. According to an aspect of the present invention, the third device cannot determine the content of the transaction input by the user but can determine whether a particular user input the content of the transaction at a particular second device, and the fourth device cannot determine the identity of the user that input the content of the transaction since the fourth device cannot determine the first device in which the content of the transaction was input by the user. According to an aspect of the present invention, the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF-SAS keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF-SAS coding keys, and the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. According to an aspect of the present invention, the user is authenticated to operate the first device according at least one biometric feature of the user or a personal identification number. According to an aspect of the present invention, the transaction of the computer system is performed between the first and the second device, the transaction is an opinion registering application, and the content of the transaction is a ballot. According to an aspect of the present invention, there is one or more first device and one or more second device. According to another aspect of the present invention, there is a virtual private network located between the second device and the fourth device and another virtual private network located between the third device and the fourth device. According to another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, including a first device generating an encoded message, including a user input content portion, according to UPTF, a second device further encoding the user input content portion of the encoded message with a coding key KVSi and generating a second device encoded message corresponding to the transaction according to UPTF, a third device receiving, decoding, and comparing the encoded messages of the first and second device to authenticate an identity of the user of the first device and to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction encoded with the code key KVsi, and a fourth device receiving the encoded content of the transaction encoded with the code key KVSi and using the code. According to an aspect of the present invention, the coding algorithm used for further encoding the user input content portion of the encoded message with the coding key KVsi is commutative with the algorithm used by the first device to generate the encoded message. According to an aspect of the present invention, the second device message does not include the user input content portion. According to an aspect of the present invention, the second device and the fourth device agree on the code key KVsi, or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key KVSi of the second device to decode the user input content portion of the encoded message encoded with the coding key KVsi. According to an aspect of the present invention, the third device cannot determine the user input content portion of the transaction, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction. According to an aspect of the present invention, the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF coding keys, and the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. According to yet another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, including a first device receiving from a second device a reference number, which relates to a not yet input transaction, the first device generating a first encoded message after the transaction, which is a user input content portion, is input by the user at the first device, such that the first encoded message includes the user input content portion that is encoded with a random code key KV, the first device generating a second encoded message including, which includes the random code key KV and the reference number, and sending the first and second encoded messages to the second device, the second device storing the first encoded message, forwarding the second encoded message to a third device, and generating a third encoded message including the random code key KV and the reference number and not containing the user input content portion, the third device receiving the second and third encoded messages, which do not have the user input content portion, decoding the messages to authenticate an identity of the user and matching content of the second and third decoded messages to authenticate an occurrence of the transaction, and forwarding the code key KV and the reference number to a fourth device, and the fourth device receiving from the second device the first encoded message and the reference number, receiving from the third device the random code key KV and the reference number, and determining from the received information the user input content portion of the transaction input by the user. According to an aspect of the present invention, the first encoded message is stored in a database of the second device and is not sent to the fourth device to be decoded until the third device has verified the identity of the user and the occurrence of the transaction. According to an aspect of the present invention, the third device never receives the user input content portion of the transaction input by the user, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction. According to an aspect of the present invention, the user input content portion of the transaction is encoded whenever sent from the first device to any other device in the computer-based system, wherein the third device never receives the user input content portion of the transaction, and wherein there is an accounting for the transaction input by the user so that errors may be located. According to still another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, including a device encoding the content of the transaction input by the user with a key known only to another device, encoding other portions of the transaction with another key known only to a secure transaction server, and sending the encoded content of the transaction and the encoded other portions of the transaction to the secure transaction server to authenticate an identity of the user of the device, wherein the secure transaction server decodes the other portions of the transaction and sends the encoded content of the transaction to the another device to be finally decoded. Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments taken in conjunction with the accompanying drawings in which: FIG. 1 is a functional block diagram of Universal Pervasive Transaction Framework system architecture according to an embodiment of the present invention; FIG. 2 is a diagram of Universal Pervasive Transaction Framework transaction messages based upon a Secure Agreement Submission (“SAS”) protocol; FIG. 3 illustrates how views are processed in the Universal Pervasive Transaction Network scheme according to an embodiment of the present invention; FIG. 4 is a flowchart of an opinion registering application of the Universal Pervasive Transaction Framework shown in FIG. 1 according to an embodiment of the present invention; FIG. 5 is a method of performing an opinion registering application in a Universal Pervasive Transaction Framework, using the system architecture shown in FIG. 1, according to an embodiment of the present invention; FIG. 6 is an illustration of how the voter device message view and the voting station message view are processed or matched in the Uniform Pervasive Transaction Network scheme according to an embodiment of the present invention; FIG. 7 is a method of performing an opinion registering application in a Universal Pervasive Transaction Framework, using the system architecture shown in FIG. 1, according to an embodiment of the present invention; FIG. 8 illustrates a message exchange of the method described in FIG. 7 according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described more fully with reference to the accompanying drawings, in which a preferred embodiment of the invention is shown. In the drawings, like reference numerals are used to refer to like elements throughout. The present invention is a computer-based system, apparatus, and method presenting a new concept for authenticating a transaction with a user in a Universal Pervasive Transaction Framework (“UPTF”). Specifically, the present invention relates to an opinion registering application, an example of which is voting. The present invention is described in terms of the way that it extends the UPTF scheme to an opinion registering application. Prior to presenting a description of the present invention, a brief overview of the UPTF is presented with reference to FIG. 1. The UPTF is explained in detail in U.S. Provisional Application No. 60/401,807, U.S. application Ser. No. 10/458,205, and U.S. application Ser. No. 10/628,583, the contents of which are all incorporated herein by reference. UPTF technology may be used in a variety of other applications, such as market transactions to enable consumers to wirelessly purchase goods and services when in proximity to the location where the goods and services are offered. Pervasive transactions typically takes place in environments with multiple access points, multiple users, multiple services and many transactions occurring in parallel. In addition, there may be eavesdroppers, unauthorized services and masquerading users. Thus, the goals of the UPTF are to authenticate a party involved in the transaction and prevent various attacks targeted at both the device and the communication levels of the pervasive transaction system. These goals may be accomplished having a coding scheme or security scheme that is symmetrical between the user and the other transaction party. FIG. 1 is a functional block diagram of UPTF system architecture to execute a transaction for an opinion registering application, according to an embodiment of the present invention. The UPTF defines a system architecture and a communication security protocol, called the Secure Agreement Submission (SAS) protocol. Essentially the UPTF offers a vessel, which is able to securely carry the individual views of a transaction agreement from each party involved in the transaction to a trusted third party for verification, using a communication network which may consist of insecure segments such as wireless LANs or cellular links. The UPTF SAS protocol will encode the messages using a symmetric, shared-secret-key approach where the secret key is known only to an individual party and a trusted third party or device. The SAS insures that the authenticity of the parties is verified and during delivery, the privacy of the information is preserved, even when the parties distrust each other and the messages from one party may be forwarded by the other to the third party verification. The UPTF also provides the mechanism for the trusted third party or device to verify that the independent views of the agreement are consistent with each other. After the agreement data is extracted from the views received from the parties and the data is verified by the trusted third party, further actions may need to be taken to actually execute the agreement. The architecture for the UPTF system shown in FIG. 1 includes a voter operating a UPTF device (called a UPTD), such as a mobile phone, called a Voter Device 110, a Voting Station 120 operating as another UPTF device, a Secure Transaction Server (STS) 130, a Voting Master 140, and several communication channels among them. The Voter Device 110, which is typically a mobile device, interacts with the Voting Station 120 to determine the details of a transaction and executes the UPTF protocol and its corresponding security operations SAS. The Voting Device 110 can support wireless communication capability necessary for discovering the Voting Station 120, communicating with the Voting Station 120, and communicating with the STS 130, as necessary. The Voting Device 110 can also have a user interface for interacting with the Voting Station 120 through some common application and the STS 130 as needed. The Voting Station 120 can also operate a UPTD and is responsible for interacting with the Voter Device 110, executing the UPTF protocol and its corresponding security operations and interacting with the STS 130. According to an aspect of the embodiment described herein, the STS 130 is a backend verification server on which both the Voter Device 110 and the Voting Station 120 have registered and provided identifying account information that is maintained in a STS database 135, which is preferably secure. The secret information used for encoding the messages to/from each Voter Device 110 and Voting Station 120 may also be stored in the STS database 135. The STS 130 receives independently generated UPTF SAS transaction views (described in more detail further below) from both the Voter Device 110 and the Voting Station 120 regarding the transaction conducted between them. The STS 130 is able to decode both of the views using information from UPTF SAS messages and the information stored in the STS database 135. Following successful decoding, the STS 130 verifies that the view messages are original, authentic, involve the intended Voter Device 110 and Voting Station 120, and that the information fields in the agreement views are consistent with each other. The STS 130 may also maintain a log of all messaging activity for non-repudiation purposes. In FIG. 1, a generic set of communication channels are explicitly shown. Channel A represents the link between the Voter Device 110 and the Voting Station 120. This link is used to negotiate the details of a transaction between the Voter Device 110 and the Voting Station 120. This aspect is application dependent and is not considered to be part of the UPTF framework. Channel A may or may not exist, if it exists it can be a wireless channel, for example, in case of a wireless local area network (“WLAN”) enabled mobile phone, and/or channel A can be physical communication between the voter and Voting Station 120 in case that the voter does not vote via the Voter Device 110. Channel B is an example of a link between the Voter Station 120 and the STS 130. Most often, channel B is not a direct link, but involves communicating through a mobile communications network and/or the Internet. In general, these are insecure channels. Channel C, from the STS 130 to the Voting Master 140 is a different type of channel and is assumed to be a highly secure communication path. In addition, STS 130 itself is assumed to be housed in a protected facility so that the STS database 135 is physically secure and inaccessible from the network. In the above-UPTF configuration, the voter is a user entering or submitting information to the Voting Station. Voting, e.g., opinion registering, is only one example of the type of information that may be submitted by the user. Likewise, the designations given to the Voting Device, Voting Station, and Voting Master are arbitrary descriptions and are not intended to limit the application of the Universal Pervasive Transaction Framework (UPTF) system architecture. The Voting Station is included to mimic conventional voting practice in which local control of the ballot distribution and local verification of the identity of the voter are desired. FIG. 2 is a diagram of UPTF transaction messages based upon a Secure Agreement Submission (“SAS”) protocol to execute an opinion registering application. The SAS protocol of the UPTF is more fully described in U.S. patent application Ser. No. 10/458,205, filed Jun. 11, 2003, entitled “Security Framework and Protocol for Universal Pervasive Transaction”, the contents of which are incorporated herein by reference. An overview of an embodiment of the SAS protocol is now presented. The Security Agreement Submission (SAS) protocol verifies a transaction in the UPTF opinion registering application scheme. An aspect of the present invention is an SAS encoding (SASE) mechanism that provides many security properties in an insecure communication environment. The SASE encodes and decodes all messages that are part of the SAS. The SASE mechanism may be implemented by each of the agreement parties, e.g., Voter Device 110, and Voting Station 120, and at least one verification party, e.g., STS 130. It is understood that encoding refers to a type of encryption, e.g., coding data such that a key is needed to read the data, and decoding refers to a type of decryption, e.g., transforming encoded data into equivalent plain text using the same or related key. The SAS protocol achieves the following desirable security properties: Authentication of agreement parties: The identities of the involved agreement parties can be determined to be who they claim they are, to a high degree of likelihood by the verification party, based on the fact that a SASE encoded message sent by an agreement party can be decoded and understood by the verification party, using a decoding method with a key that is specific to the sender and only known to the verification party and the specific agreement party. Authentication of verification party: The identity of the verification party can be determined to be who it claims it is, to a high degree of likelihood by each individual agreement party, based on the fact that a SASE encoded message sent by the verification party for a particular agreement party can be decoded and understood only by that agreement party using a decoding method with a key specific to the agreement party and only known to the agreement party and the verification party; Anonymity: The agreement parties may remain anonymous to each other, if desired in an application through the use of the SASE method. Privacy of Agreement: The agreement data sent between the agreement parties and the verification party is protected by SASE so that, if intercepted, no party other than the intended receiver is able to decode and read the data. Similarly, response messages from the verification party to the agreement parties may also be protected. Tamper-resistance: The agreement data sent between the agreement parties and the verification party may be protected through the use of an encryption signature so that no party can alter the data sent by other parties without a high degree of detection. Non-replayable: Agreement data sent between the agreement parties and the verification party (if intercepted) may be protected by any standard encoding mechanism by using the key only once and including a value that is only used once by the sender and encoded in the view. For example, the encoding mechanism may incorporate the value of the time when the agreement transaction occurs, and such a timestamp is also included in each message and recorded by the verification party. Thus, no party can replay the agreement data to forge a new agreement because each key is associated with a specific timestamp, which is recorded by the verification party in a message log. Therefore, since the STS 130 logs or records messages according to a specific time stamp, the STS 130 will identify the agreement data or transaction according to the time stamp for each message. Non-repudiation: An agreement party cannot later claim that they did not generate an agreement message that has been verified by the verification party except under certain specific conditions, which are highly unlikely. These security breaches might include a situation where all of the secret parameters (the device-specific stored parameters and the shared secret which is input by the user of the device) have been divulged or discovered and the UPTD (Voter Device 110) has been used without the consent of that agreement party. It is also possible for the verification party to generate a false agreement, but it would involve the collusion of the verification party and the other parties to the agreement, which is also highly unlikely. In addition, the verification party will keep records that record the sequence of SAS message exchanges involved in each transaction. Agreement Group Authentication: The present invention ensures the integrity of the agreement party group (the group consisting of and only of the parties among which the agreement is conducted) so that no other party may pretend to be an agreement party or an agreement party can pretend not to be an agreement party. This is accomplished explicitly by a membership list and identity cross-referencing. It is also assumed that all participants in the agreement are previously known to the verification party and able to be individually authenticated. For example, a verification party sends a message to all who are eligible to participate in an opinion registering application and identifies each eligible participant who actually participated in the opinion registering application by cross-referencing each actual participant with the membership list. Agreement Verification: The agreement is verified to be consistent among the authenticated agreement parties through the use of redundant and cross-referencing information contained in the agreement data from each party and the use of a verification procedure consisting of basic matching rules and specific matching rules that may depend on the application. Computational Efficiency: The security mechanism of the present invention is based on private key (symmetric) cryptography that is more efficient than alternative methods. Physical Security: The security mechanism may be implemented so that it is not necessary to store all of the necessary encoding information on the UPTD or Voter Device 110, thus making it easier to protect the secret information if the Voter Device 110 is compromised. Specifically, the shared secret input by the user or voter is not stored on the Voter Device 110. Also, when the Voter Device 110 is used in a particular application context, user-identifying information is not stored on the Voter Device 110. For example, when the Voter Device 110 is used for submitting an opinion registering transaction, the name of the voter, or the voter's account information is not stored on the Voter Device 110. Intrusion Detection: The security mechanism is centralized through the use of an independent verification party so that attempts to use the system by unauthorized users that rely on multiple access attempts are easily detected and handled accordingly. With the above-mentioned aspects of the present invention, the present invention is ideal for being used as a vessel to carry opinion registering transaction data in an insecure communication environment. The following includes additional details of the SAS protocol of the UPTF and the encoding mechanism provided with reference to FIG. 2, for example. The internal structure and the generation process of message views 202, 204 (e.g., UPTF SAS transaction messages) are shown in FIG. 2. The UPTF SAS based message views 202, 204 are implemented and executed by software and/or hardware of the Voter Device 110. Since the message views 202, 204 from the Voter Device 110 and the Voting Station 120, respectively, are symmetrical, the voter device message view 202 is only described. The symbols used in FIG. 2 are explained below: DID1: device ID, a unique identifier for the Voter Device 110. DID2: device ID, a unique identifier for the Voting Station 120. RSN: random sequence number. TS: local current timestamp. TID: transaction ID, a unique identification number assigned to an agreement. MD: message digest. PIE: Personal identification entry, a user, e.g., voter, and STS 130 maintained input secret entry, such as an alphanumeric string. In a typical embodiment described herein, the PIE is only maintained by the user (voter) and the STS 130, is not known to and/or maintained by another party and/or the Voting Master 140, and is temporally known as an intermediate parameter to the Voter Device 110 for encoding the voter device message view 202. The PIE can be a short alphanumeric string, such as a 4 digit number. The PIE is entered by the user whenever the user attempts a transaction. Preferably the PIE is issued to the user following the registration of the user for the application that the Voter Device 110 is used for. The PIE can also be selected by the user at such time. The PIE is an alphanumeric string. In order to speed up the user entry to make it easier for the user to remember the PIE, the PIE can be a number such as 4-digit or 5-digit personal identification number (“PIN”). The PIE is, however, a piece of highly secure information in the sense that the PIE is never transmitted during the UPTF protocol execution, the PIE is only known to the user and the STS 130, and secrecy of the PIE is well protected. It is assumed that the PIE can be input by the user on a Voter Device 110 in a secure fashion or it may be deterministically generated using a biometric device, such as a fingerprint sensor. For example, a computation applied on the fingerprint data received from a fingerprint sensor can be used to generate a PIE that is initially communicated by the user to the STS 130. Whenever the user attempts a transaction, the user applies her finger to the fingerprint sensor, thus generating the PIE. The PIE should not be kept in permanent storage on the Voter Device 110, but can be used as an intermediate parameter required for the generation of the encoding key for a transaction. The PIE should not be retained by the Voter Device 110 for a period longer than the transaction execution time. If a particular implementation of the present invention uses a form of PIE that is not convenient for a user to input for each agreement transaction and the Voter Device 110 needs to store the user's PIN, the storage must be secure and tamper-resistant. As shown in the FIG. 2, a voter device message view 202 comprises a cipher text portion (or encoded portion) 206 and a plaintext (e.g., perceptible) portion 208. A plaintext portion 208 includes the TID, the DID1 of the Voter Device 110 generating the voter device message view 202, and the local current TS of Voter Device 110. The TS is used to prevent transaction replay. The encoded portion 206 comprises two critical fields: the agreement data and the DID2 of the Voting Station 120 involved in the agreement. The DID2 is the minimum necessary reference field in order to provide the desired verification properties of the SAS protocol. Therefore, a user can execute a Voter Device 110 transaction with a transaction verification party (e.g., STS 130) using a PIE and transaction messages comprising an identifier of the Voter Device 110, an identifier of the second transaction party, e.g., Voting Station 120, and an identifier for a transaction. For example, the DID, and the TS obtained from the local clock of the Voter Device 110 (and/or as provided as a part of the agreement data), are input to a pseudorandom number generator of the Voter Device 110 to generate a time-dependent RSN. Therefore, the parameters of the generator are particular to each Voter Device 110. The encoding key K is generated from the RSN and PIE, which is generated by the STS 130. The RSN and PIE are combined using a function F and a hash function H is applied to the result (typically a string) to generate the encoding key: K=H(F((PIE, RSN)) A message digest function can be applied to the agreement data, the DID2, and the DID, to generate a MD of the view. The MD can further strengthen the security by ensuring that no other party has tampered with or modified the contents of the voter device message view 202 in any way. The encoding algorithm with the encoding key K is applied to the MD, the agreement data, the DID,, and the DID2 to generate the cipher text portion of the voter device message view 202, as shown in FIG. 2. For further protection, the SAS protocol may use additional encoding standards to prevent “known-text” attacks. The STS 130 has sufficient prior knowledge of the functions and specific parameters used by each Voter Device 110 in the encoding process, so that when combined with the plaintext portions of a message view 202, 204, it is possible to decode the message view 202, 204 by reversing the above process. For example, from the plaintext portion 208 of the voter device message view 202, the STS 130 recovers the DID, and TS, which are used to look-up the voter PIE and other parameters of the RSN generator that can be stored in the STS database 203. These are used to compute the RSN. The encoding key K can be computed using the same method with which the Voter Device 110 generates the encoding key. The cipher text portion 206 of the voter device message view 202 is then decoded. After all fields of the voter device message view 202 are acquired, the STS 130 locates the voting station message view 204 for the same transaction, using the DID2 and TID included in the previously decoded voter device message view 202. After going through a similar decoding process, the decoded fields of the agreement data of the voting station message view 204 are compared with the corresponding fields from the voter device message view 202. If all the corresponding fields match, the received message views 202, 204 are considered verified. Further processing is carried out and external executions are triggered as necessary. Any responses from the STS 130 to the Voter Device 110 or Voting Station 120 are encoded by the STS 130 using the same encoding methods and using the parameters for the encoding of the original transaction at the Voting Device 110. Only the intended user can decode the response message, insuring privacy protection and authentication of the STS. For a complete account of the encoding key generation for the UPTF SAS describe above, refer to U.S. Provisional Application No. 60/401,807, U.S. application Ser. No. 10/458,205, and U.S. application Ser. No. 10/628,583, the contents of which are incorporated herein by reference. A detailed description of the present invention is now presented. The embodiments of the present invention are described in terms of applications, such as an opinion registering application, which may be implemented using the UPTF described above. Each of the applications discussed below that may be implemented using a similar framework, devices, architecture, and overall framework as described above for the UPTF. The modifications, for example, of the UPTF concern the notion of a transaction and an extension to the overall architecture that guarantees the anonymity of the UPTD's owner, such as the user of a mobile phone, who submits the transaction using the mobile phone. According to an embodiment of the present invention, referring to FIGS. 1 and 3, a voter downloads a voting application and executes a voting application that is offered by the Voting Station 120 on a UPTD Voter Device 110 (“Voter Device”) and selects a ballot to be filled (operation 310). The ballot is submitted to the Voting Station 120 (operation 220). Preferably, the ballot is securely submitted to the Voting Station 120 so that a third party cannot determine the voter, e.g., registered user of the Voting Device 110, and content of the ballot being submitted. The Voter Device 110 may encrypt the ballot so that its contents are hidden from the Voting Station 120. The voter may be any user of the opinion registering application implemented using the UPTF. Again, the voting application is not limited to a voting application and includes any application, e.g., survey, opinion poll, requiring a user to submit information on a form to be transmitted. Further, the present invention is not limited to there being only one voter and only one Voting Station 120. For example, there may be multiple voters submitting ballots to a single Voting Station 120 or Voting Stations 120. The Voting Station 120 further encodes the vote with a coding key KVsi, which is generated by the Voting Station 120 according to an encoding method of the UPTF protocol (operation 330). The encoded vote with the coding key KVsi is referred to as the agreement (transaction) in the UPTF scheme. The Voting Station 120 and the Voter Device 110 both prepare messages for the STS 130 according to, for example, the above described SAS protocol for the UPTF scheme (operation 340). The encoded portions of the messages prepared by the Voter Device 110 and the Voting Station 120 are encoded with the two parties respective keys (hashes of the RSN and the corresponding PIN's), which are only known, or can only be inferred, by the STS 130. However, the portion of the message that is the encoded ballot cannot be decoded by the STS 130. The encoding of the encoded portions of the messages is not limited to the above-described encoding mechanism. The STS 130 receives the messages prepared by the Voting Station 120 and the Voting Device 110 via a communication link. The STS 130 decodes the received messages to verify that a particular voter voted at a particular Voting Station 120 (operation 350). Upon such determination, the STS 130 sends the agreement (encoded vote with the coding key KVsi and a message digest) and a reference of the submitting Voter Station 120 to the Voting Master 140 (operation 360). The Voting Master 140 assesses the identity of the submitting Voting Station 120 and subsequently retrieves the corresponding coding key KVsi from the submitting Voting Station 120 to be used to decode the vote (operation 370). The coding key KVsi is transmitted via a secure communication link between the Voting Station 120 and the Voting Master 140 or is known a priori to the Voting Master 140. The coding key KVsi is only known to the Voting Station 120 and the Voting Master 140 and the vote cannot be decoded, e.g., determined, without using coding key KVsi. In the case that the coding key KVsi is not known a priori to the Voting Master 140, the key may be transferred to the Voting Master 140 immediately upon being generated by the Voting Station 120 or transferred to from the Voting Station 120 to the Voting Master sometime after the STS 130 sends the agreement to the Voting Master 140. The Voting Master 140 performs various operations, such as confirming the validity of the vote received by the STS 130 (ensuring non-duplication of voting and using the message digest for tamper detection) (operation 380). Further, the STS 130 may send a confirmation message of the voting operation to the Voter Device according to the UPTF protocol discussed in U.S. Provisional Application No. 60/401,807, U.S. application Ser. No. 10/458,205, and U.S. application Ser. No. 10/628,583. According to the above-described embodiment of the invention, it is assumed that the STS 130 and the Voting Master 140 are not in collusion. For example, the STS 130 cannot determine the vote because the STS 130 cannot decode the agreement without the coding key KVsi. The Voting Master 140 cannot determine the identity of the voter that submitted the ballot because the Voting Master 140 cannot determine the Voter Device 110 in which the ballot was submitted. Should there be collusion between the STS 130 and the Voting Master 140, any secrecy could be compromised because the STS 130 will additionally know the content of the vote or ballot and the Voting Master 140 will additionally know the identity of the voter that submitted the ballot. Further, according to the above-described embodiment of the invention, a voter may authenticate self to the Voter Device 110 via a PIN or biometric features, e.g., fingerprints or retina scan. The STS 130 is able to confirm and/or record that a particular voter cast a vote at a particular Voting Station 120. The Voting Station 120 knows that a Voting Device 110 is submitting a vote, but has no knowledge of the identity of the registered owner of the Voting Device 110 (voter), thus only the DID, is known to the Voting Station 120. Only the STS 130 can resolve a DID, to its registered owner; however, the STS 130 cannot know the content of the vote because the vote has been encoded with a coding key KVsi that is unknown to the STS 130. The Voting Master 140 is able to decode and determine the content of a vote but is unaware of the identify of the voter who submitted the vote; instead, the Voting Master 140 only knows at which Voting Station 120 the vote was submitted. According to the above-described embodiment of the invention, the UPTF framework assures the following: Authentication of the voter; Non-tampering of the vote, which preserves voting integrity; Non-repudiation of the voting act, since the STS registers the origin of the vote, e.g., which Voting Station 120 and of the voter who submitted the vote; and Secrecy of the submitted vote since the vote is only known to the Voting Master 140, which is unaware of the identity of the voter who submitted the vote. Further, during the browsing part of the above-described opinion registering application, for the purpose of the voter's selection and submission of the vote there is some normal security provided although it is not sufficient for the properties of the UPTF. For example, it may be the case that the over the air exchanged traffic is encoded at the link layer through security provided by a network protocol used between the Voter Device 110 and an access point of the Voting Station 120. But, if such traffic is not properly encoded, a third party could observe the votes traveling through the air. Although the third party would not be able to associate a specific vote to a voter using a particular Voter Device 110, since the voter's identity is never a part of the exchange, nor is the voter's identity communicated by the Voter Device 110 to the Voting Station 120. Nevertheless an additional application would be possible, namely a sampling a number of cast votes, similar to exit polls in today's systems. According to another embodiment of the invention, the embodiments discussed above may be used in an e-government application. For example, this dual-purpose use of the UPTF framework would be beneficiary to the deployment of UPTF, especially by disseminating UPTD's in the hand of voters who also happen to be consumers. As discussed above, the present invention significantly broadens the scope of applications of the UPTF. In addition, there are many benefits provided by the opinion registering application using UPTF described in the embodiments of the present invention. For example, the voting station is relatively easy to set up, the voting equipment is inexpensive and less personnel is necessary for carrying out the voting process, the process is flexible and fast for voters, parallelization of the voting actions (simultaneous voting), there is no waiting in line, and voters are not limited to voting in any one particular voting station. FIG. 4 is a flowchart of an opinion registering application of the UPTF shown in FIG. 1 and described in the above embodiments of the present invention. In FIG. 4, operation 410 relates to an initial operation when a prospective voter visits a voting registration center and is given a Voter Device 110 to use for voting purposes. For example, the operation shown in FIG. 4 may occur during a polling station e-voting application. In operation 420, biometric data of the voter is associated with a particular Voter Device 110. For example, the voter may have their fingerprint associated with a particular Voter Device 110. In operation 430, the biometric data is stored on the Voter Device 110 to be used for verification purposes when someone else attempts to activate or use the same Voter Device 110. Therefore, only a voter with a matching fingerprint can use the Voter Device 110. Further, the act of imprinting the fingerprint, or other biometric data, should take place in the presence of an official voting representative to confirm the identity of the voter attempting the imprint. The foregoing procedure will better guarantee the identity of the voter casting a vote using a particular Voter Device 110. The Voter Device 110 will display an error message if an unauthorized user attempts to use the Voter Device 110, as shown in operation 440. Another embodiment of the present invention, having similar devices, architecture, overall framework, and modifications over UPTF as in the embodiments discussed above, is described below and illustrated in FIGS. 1 and 5. FIG. 5 is a flowchart of another method of performing an opinion registering application in a UPTF using the system architecture shown in FIG. 1. The modifications and properties discussed in the above-described embodiments are assumed to be present in the embodiments described below. In FIG. 5, the voter browses the voting application at the Voter Device 110 and uploads or sends to the Voter Device 110 an application that represents an unfilled ballot or not-yet completed ballot (operation 505). The application is typically uploaded from the Voting Station 120. The voter fills the ballot using the Voter Device 110 (operation 510). It is assumed that no third party can see the voter filling the ballot at the Voting Device 110. The Voter Device 110 separately encodes the ballot and the cross-reference identifying information for the Voting Station 120 with a voter device key known to the STS (operation 515). Such encoding is performed according to the UPTF protocol. For example, the voter device key may be generated using a hash of time-specific RSN and a user PIN. The voter device key is referred to as KVDi. The Voter Device 110 adds or includes with the encoded contents the other self identifying information that are present in a typical voter device message sent to the STS 130. For example, the encoded contents of the typical voter device message comprise ballot and cross-reference identifying information and a message digest that is calculated from the contents. The Voter Device 110 sends this message, referred to as the voter device message, to the Voting Station 120 (operation 520). For example, the voter device message may also be received by the Voting Station 120 via communication access points 127, which provide wireless connectivity between the Voter Device 110 and the Voting Station 120. In another embodiment of the present invention, the message is transmitted as a message over a cellular network from a mobile phone. The Voting Station 120 receives the voter device message and the Voting Station 120 encodes a portion of the already encoded ballot component again with a coding key KVsi (operation 525). The coding key KVSi is generated by the Voting Station 120 according to an encoding method of the UPTF protocol. The portion of the ballot that is further encoded is the vote. The encoded vote with the coding key KVSi is referred to as the agreement (transaction) in the UPTF scheme. This agreement (encoded vote) needs to be transmitted to the STS 130 either as the data portion of the voter device message or the voting station message. As one embodiment described further below discusses, the Voting Station 120 replaces the encoded ballot in the voting device message with the agreement. In an equivalent embodiment, the encoded ballot is deleted from the voting device message and is included as the agreement in the voting station message. In the following description, we assume the former approach. The coding key KVSi generated is only known to the Voting Station 120 and the Voting Master 140 and the vote cannot be decoded, e.g., determined, without using coding key KVSi. The coding key KVSi may be transferred to the Voting Master 140 immediately upon being generated by the Voting Station 120 or transferred to from the Voting Station 120 to the Voting Master sometime after the STS 130 sends the agreement to the Voting Master 140. The encoded portion of the voter device message becomes “KVSi(STS_KVDj(ballot))+STS_KVDj (cross-reference identifying information)”; this modified message is used as the voter device message view which is sent to the STS 130. Similarly, this could also be used as the voter station message without loss of generality. Briefly, a message view consists of an encoded portion and a plaintext portion. For example, with respect to the voter device message view, the encoded portion consists of reference identification information, such as DID2, and agreement data (encoded vote with the coding key KVsi), and a message digest to prevent tampering of the ballot, and the plaintext portion consists of additional reference identification information, such as transaction ID, Time Stamp, and DID1. Upon further encoding of the ballot received by the Voter Device 110, the Voting Station 120 generates a voting station message view using a predetermined mechanism and format according to the SAS protocol of the opinion registering application of the UPTF (operation 530). For example, the Voting Station 120 generates the voting station message view using the same mechanism and format as the merchant as specified by the UPTF in U.S. Provisional Application No. 60/401,807, U.S. application Ser. No. 10/458,205, and U.S. application Ser. No. 10/628,583. However, the transaction portion of the voting station message view does not include any data. Thus, the transaction portion of the voting station message view may be omitted. Further, the encoded portion of the voting station message view is encoded using another coding key referred to as a voting station key that is generated according to UPTF. The voting station message view, for example, has an encoded portion, which consists of reference identification information, such as DID1, and a plaintext portion, which consists of additional reference identification information, such as transaction ID, Time Stamp, and DID2. The voter device message view and the voting station message view are sent from the Voting Station 120 to the STS 130 (operation 535). The message views may be sent to the STS 130 via any communication link and may be sent through a network, such as the Internet. The STS 130 “opens” (decodes) both views by applying a decoding operation according to UPTF (operation 540). For example, the decoding operation may be the same as the decoding operation specified in U.S. Provisional Application No. 60/401,807, U.S. application Ser. No. 10/458,205, and U.S. application Ser. No. 10/628,583. The STS 130 is able to decode both views because the STS 130 is able to determine, or infer, the voting station key and Voter Device 110 coding key KVDi from the communications of the Voter Device 110 and the Voting Station 120 to the STS 130. In particular, after the STS 130 decodes both message views, the encoded part of the voter device message view reveals: “KVSi(ballot)+cross reference identifying information+message digest from voting device”. The STS 130 confirms from the decoded message views that the cross reference identification information of the voting station message view matches the corresponding identification information of the voting station message view. Specifically, the STS is able to confirm that the cross reference identifying information of the decoded voting station message view matches the corresponding identifying information of the voter, which is included in the voter device message view. After both message views are successfully decoded, the STS 130 verifies the agreement by executing a procedure consisting of, for example, a list of matching rules to be applied to both message views. Thus, a series of basic matching operations between both message views are performed and then optionally, application specific matching rules can be applied. If one of the matching rules fails, the verification or matching process is stopped and the STS 130 may generate and send an error message to the Voter Device 110 and/or Voting Station 120 and/or Voting Master 140. At the completion of the verification or matching process, the STS 130 may forward the agreement plus relevant information such as the message digest, which is taken from the decoded message views, to a processing component, such as a Voting Master 140. The verification or matching process may be implemented on a different device but able to communicate with the STS 130 through a reliable and secure communication channel. The STS 130 sends the agreement (still encoded using KVSi) to the Voting Master 140, along with reference information that identifies the submitting Voting Station 120 (operation 545) and possibly the message digest. Similar to the above-described embodiments, upon receiving the agreement and the reference information that identifies the submitting Voting Station 120, the Voting Master 140 assesses the identity of the submitting Voting Station 120 and subsequently retrieves the corresponding coding key KVsi from the submitting Voting Station 120 to be used to decode the vote (operation 550). The coding key KVsi is sent via a secure communication link between the Voting Station 120 and the Voting Master 140. The coding key KVsi is only known to the Voting Station 120 and the Voting Master 140 and the vote cannot be decoded, e.g., determined, without using coding key KVsi. The coding key KVsi may be transferred to the Voting Master 140 immediately upon being generated by the Voting Station 120 or transferred to from the Voting Station 120 to the Voting Master 140 sometime after the STS 130 sends the agreement to the Voting Master 140. The Voting Master 140 performs various operations, such as confirming the validity of the vote received by the STS 130 (ensuring non-duplication of voting) (operation 555). In addition, the Voting Master 140 can further determine whether the ballot has been modified from the original version supplied by the Voter Device 110 by computing the message digest and checking whether the message digest matches the one supplied by the Voter Device 110 and supplied by the STS 130. The Voting Master 140 can send a confirmation message of the voting operation to the STS 130. Further, the STS 130 may send a confirmation message of the voting operation to the Voter Device 110 and the Voting Station 120 according to the UPTF protocol (operation 560). FIG. 6 illustrates how the voter device message view and the voting station message view are processed or matched in the Uniform Pervasive Transaction Network scheme according to an embodiment of the present invention. In FIG. 6, the top box 610 illustrates how the voter device message view is processed at the Voter Device 110, Voting Station 120, and STS 130, respectively. The bottom box 650 illustrates how the voting station message view is processed at the Voting Station 120 and STS 130. In the middle of the figure, the double-arrowed lines 680 and 690 illustrate how the matching is performed at the STS 130. An original voter device message view 620 includes a plain text portion and an encoded portion. The plain text portions are those portions that are not encoded. The plain text portions of the original voter device message view 620 include a voter device identification number (DID1) 622 and a time stamp (TS) 624. The encoded portions of the original voter device message view 620 include a ballot 626 and a voting station device identification number (DID2) 628 and a message digest. The encoded portions are encoded by the Voter Device 110. The voting station further encoded voter device message view 630 includes plain text portions, encoded portions encoded by the Voter Device 110, and a portion further encoded with a coding key KVSi. The plain text portions of the voting station further encoded voter view 630 include a voter device identification number (DID1) 632 and a time stamp (TS) 634. The encoded portions of the original voter device message view 630 include a ballot 636 and a voting station device identification number (DID2) 638 and a message digest. The portion of the Voting Station 120 further encoded voter device message view 630 further encoded with the coding key KVSi is the ballot 636. The STS decoded voter device message view 640 includes plain text portions and a portion encoded with the coding key KVSi. The plain text portions of the STS decoded voter device view 640 include a voter device identification number (DID1) 642, a time stamp (TS) 644, and a voting station identification number (DID2) 648 and a message digest. The portion of the STS decoded voter device message view 640 encoded with the coding key KVSi is the ballot 646. The original voting station message view 660 includes plain text portions and an encoded portion. The plain text portions of the original voting station message view 660 include a voting station identification number (DID2) 662 and a time stamp (TS) 664. The encoded portion of the original voting station message view 660 includes a voter device identification number (DID1) 666. The STS decoded voting station message view 670 includes only plain text portions. The plain text portions included in the STS 130 decoded voting station view 670 include a voting station identification number (DID2) 672, a time stamp (TS) 674, and a voter device identification number (DID2) 676. The STS decoded voter device message view 640 and the STS decoded voting station message view 670 are both sent from the Voting Station 120 to the STS 130. As previously discussed, the STS 130 confirms whether the cross reference identifying information of the decoded voting station message view matches the corresponding identifying information of the voting station message view using a predetermined mechanism and format according to an SAS protocol of the UPTF to authenticate the voter and Voter Device 110. The double arrows 680 and 690 shown in FIG. 6 illustrate the matching process that is done at the STS 130. Arrow 680 depicts the matching process of the voter device identification number (DID1) 642 of the STS decoded voter device message view 640 with the voter device identification number (DID1) 676 of the STS decoded voting station message view 670. Arrow 690 depicts the matching process of the voting station identification number (DID2) 648 of the STS decoded voter device message view 640 with the voting station identification number (DID2) 672 of the STS decoded voting station message view 670. Further, since the STS 130 does not know the coding key KVSi, which is only known to the Voting Master 140 and Voting Station 120, and the encoding using the coding key KVSi is applied after the Voter Device 110 encodes the ballot and the cross-reference identifying information for the Voting Station 120, for the STS to be able to decode the encoding added by the Voter Device 110, the encoding algorithm should be commutative. For example, if Ki and Kj are encoding operations and x is text to be encoded then Ki(Kj(x))=Kj(Ki(x)). As a result KVSi(STS_KVDj(ballot))=STS_KVDj(KVSi(ballot)). The STS 230 is aware of STS_KVDj and thus can decode STS_KVDj(KVSi(ballot)) and reveal the KVSi(ballot). One example of a commutative cipher is the XOR stream cipher. Other common commutative ciphers use the Pohlig-Hellman Algorithm or the Shamir-Omura algorithm. The first is based on Elliptic Curve Cryptography (ECC), and the other is based on RSA cryptography. In order for the Voting Station 120 to further encode the ballot portion of the message from the Voter Device 110, the encoded ballot should be identifiable. For example, the encoded ballot may also be given to the Voting Station 120 as a separately encoded data item. The Voting Station 120 will further encode with the coding key KVSi only the part of the voter device message view that represents the ballot. The above-described embodiments, as illustrated in FIGS. 1, 5, and 6, address the issue of not having an non-encoded vote being exchanged on a potentially non-encoded communication link. Non-encoded votes being exchanged on non-encoded communication links would be inviting to eavesdroppers, unauthorized services and masquerading users. Thus, the above-described embodiments prevent various attacks targeted at both the Voter Device 110 and the communication levels of the pervasive transaction system. Another embodiment of the present invention, having similar devices, architecture, overall framework, and modifications over UPTF as in the embodiments discussed above, is described below and illustrated in FIGS. 1 and 7. In the below-described embodiment of the invention, the STS 130 does not receive or handle the ballot, thereby preventing the opportunity for the STS 130 and the Voting Master 140 to be in collusion with each other to determine the identity of a particular voter who cast a particular ballot. The message digest can be used to detect if the Voting Station 120 has modified the ballot submitted by a Voter Device 110. The below-described embodiments include at least the following additional properties. The embodiments do not require the encryption algorithms to be commutative. Further, it is possible to ensure that all votes have been counted by way of cross checking all votes responded to by the STS 130, since all votes are associated with a particular voting number. For example, because all votes are associated with a voting number, when you count the votes and it is known how many voting numbers are issued, you can compare the number of votes counted with the number of voter numbers issued, e.g., total number of eligible voters. The modifications and properties discussed in the above-described embodiments are assumed to be present in the embodiments described below. FIG. 7 illustrates another method of performing an opinion registering application in a UPTF using the system architecture shown in FIG. 1. However, the system architecture further includes a virtual private network (“VPN”) located between the Voting Master 140 and each of the Voting Stations 120 (only one shown in FIG. 1) and another VPN located between the STS 130 and the Voting Master 140. The VPNs are not shown in FIG. 1. Including the VPNs in the system architecture does change the essential features of the method of performing the opinion registering application in the UPTF. At least one of the VPNs may be applied to any of the above-described embodiments of the present invention. Briefly, the VPN is a way to communicate through a dedicated server securely to a network over the Internet and provide additional security to wireless local area networks (“LAN”). The Voting Master 140 provides the STS 130 with at least the following information: address of each Voting Station 120 to be used for the voting application, list of voter identifiers or device ID's of voters which will be invited to participate in the voting, start and end time for voting, and an empty ballot (Be). The STS 130 contacts all the voters on the list of voters provided by the Voting Master 140 and invites the voters to vote at the start time of the voting process (operation 710). For example, a voter may be contacted via an invitation message sent to the voter's Voter Device 110 (PDA, cellular telephone, computer, etc.). Upon being invited to participate in the voting, the voter, via the Voter Device 110, contacts the STS 130 to request a ballot (operation 715). For example, the voter may contact the STS 130 through a reply message on the Voter Device 110. The STS 130 determines whether the invited voter is intended to vote, and if so, transmits an empty ballot to the appropriate Voter Device 110 for the voter to vote (operation 720). For example, the STS 130 may determine the intended voters from a voter database 135 that stores identification information. Preferably, the voter database 135 is a secure database to prevent unauthorized users or devices from obtaining the information. As previously discussed, the STS 130 is able to determine a particular voter from a Voter Device 110 and a particular Voting Station 120. In addition, the transaction between the STS 130 and the Voter Device 110 may be encoded to prevent tampering with the empty ballot upon delivery. Further, the STS may log or store the requests for accounting purposes. The voter enters the information onto the ballot (Bf) (operation 725). The ballot does not need to be completed by the voter before being cast or submitted. Thus, a completed ballot does not necessarily indicate that the entire ballot was filled in or that all possible votes were made. When the ballot Bf is created, the Voting Station 120 uploads a voting number (“VN”) to the Voter Device 110 (operation 730). For example, the VN is a random number, unique for each voting transaction, with an optional voting station prefix. The Voter Device 110 generates a ballot message, encoded with a new key created by the device, KV (operation 735). The encoded ballot message looks as follows. MENCODED—BALLOT=Kv[Bf+VN+Time],VN The Voter Device 110 also generates a voter device transaction view message, from the Voter Device 110 (operation 740). In the body of the transaction of the voter device transaction view message is the VN and KV, and optionally the time of voting (time stamp). The Voting Station 120 receives both messages, the encoded ballot message and the voter device transaction view message (operation 745). The Voting Station 120 determines whether the VN received in the MENCODED—BALLOT message is the same as the VN uploaded in the Voter Device 110 by the Voting Station 120 (operation 750). Such determination is done to prevent or learn of tampering with the message in the wireless link between the Voter Device 110 and the Voting Station 120. The Voting Station 120 creates a voting station transaction view message (operation 755). The voting station transaction view message is generated according to the same methods as discussed in the above-described embodiments of the present invention. For example, in the body of the voter device transaction view message is the VN and optionally, the time when the vote was submitted (time stamp). The Voting Station 120 sends both the voter device transaction view message and the voting station transaction view message to the STS 130 (operation 760). However, the encoded ballot message is not sent to the STS 130 and is instead stored in a local database in the Voting Station 120. In the local database of the Voting Station 120, each encoded ballot message is indexed according to its VN. In the local database of the Voting Station 120, the encoded ballot message will be marked as not recounted and not acknowledged. The local database of the Voting Station 120 may also include information about the voter, so that, for example, if the vote is encoded, the Voting Station 120 could know which voter had voted, but not know the content of the vote. The STS 130 receives both transaction view messages and determines whether the voting transaction is valid, e.g., verifies that a particular voter voted at a particular Voting Station 120 (operation 765). Neither of the transaction view messages includes the ballot (agreement). Therefore, the STS 130 is incapable of determining the content of the ballot, regardless if the STS 130 is in collusion with the Voting Master 140. The STS 130 determines the validity of the voting transaction according to the same method as discussed with the above-described embodiments of the present invention. For example, the STS 130 confirms from the decoded message views that the cross reference identification information of the voting station message view matches the corresponding identification information of the voting station message view. Specifically, the STS 130 is able to confirm that the cross reference identifying information of the decoded voting station message view matches the corresponding identifying information of the voter, which is included in the voter device message view. When the STS 130 determines the voting transaction to be valid (as determined by a SAS protocol for the opinion registering application 200 of the UPTF), the STS 130 transmits an acknowledge message to the Voting Station 120, along with a VN. The Voting Station 120 will mark the message as acknowledged. The foregoing process will continue until the end time for voting arrives, as determined by the Voting Master 140. When the end time for voting arrives, the STS 130 transmits a message to all of the invited voters and to all corresponding Voting Station 120 to finish all voting transactions (operation 770). The STS 130 sends a message to the Voting Master 140, including the coding key KV and the corresponding VN (operation 775). The STS 130 may additionally include in the transaction to the Voting Master 140 the identification of the Voting Station 120 that stores the encoded ballot corresponding to each VN. The Voting Master 140 sends a message to all the Voting Station 120 requesting for the received VN (operation 780). However, if the STS 130 has informed the Voting Master 140 about which Voting Station 120 holds the encoded ballot for each VN, then the Voting Master 140 will not contact all Voting Station 120. The Voting Station 120 storing the VN in its local database surrenders the MENCODED—BALLOT's to the Voting Master 140, and labels that vote as recounted (operation 785). However, if the vote has not been acknowledged by the STS 130, then an error message may be sent to the Voting Master 140. The Voting Master 140 is in possession of MENCODED—BALLOT and the coding key KV and decodes each ballot (operation 790). As previously discussed, the Voting Master 140 cannot know which voter cast a particular vote, as the Voting Master 140 is only in possession of the coding key KV, the ballot, and the VN. None of this information supplies any information about the voter; therefore, the Voting Master 140 cannot determine which particular voter cast the particular vote. Further, when the voting time ends, each Voting Station 120 could know which ballots where successfully retrieved, which ballots where acknowledged, and which ballots were recounted. As such, a verifiable database of the votes, indexed by VN, may be determined and stored. FIG. 8 illustrates a message exchange of the method described above and shown in the flowchart of FIG. 7. Positioned horizontally across the top of FIG. 8, from left to right, respectively, are markers identified as the Voter Device 110, Voting Station 120, STS 130, and Voting Master 140. Below the markers are horizontal lines in descending order showing the location of a transaction at various stages of the message exchange, with respect to the markers, according to an embodiment of the invention. According to FIG. 8, the Voting Station 120 initially sends at least the address, list of identification numbers that will participate in the voting, empty ballots, and start time and end time of voting, to the STS 130, as shown in Line 1. Next, as shown in Line 2, the STS 130 contacts all the voters listed that are invited to participate in the voting. For example, a message, such as a text message, may be transmitted to the Voter Device 110 indicating that the voter is invited to participate. Next, as shown in Line 3, the voter requests an empty Ballot (Be) from the STS 130. For example, a voter request message is sent from the Voter Device 110 to the STS 130. This message may be encoded according to UPTF, as discussed in the above-described embodiments of the present invention. The voter request transaction may additionally be recorded by the STS 130 for consistency and record keeping purposes. Next, as shown in Line 4, the STS 130 sends Be to the Voter Device 110 so that the voter may perform the voting operation. This message may be encoded according to UPTF, as discussed in the above-described embodiments of the present invention, to prevent fake, tampered, or unofficial ballots from being sent to voters. Next, as shown in Line 5, a request to vote is sent by the Voter Device 110 to the Voting Station 120. The request to vote may be sent to provide further voting protection and allow the Voting Station 120 to check the Be for consistency to ensure that no tampering with the ballots was done at the STS 130. Next, as shown in Line 6, a VN is sent to the Voter Device 110 from the Voting Station 120. For example, the VN is a random number generated by the Voting Station 120. The VN may be generated based on a RSN, time stamp, etc. Next, as shown in Line 7, the Voter Device 110 generates a coding key Kv. For example, the coding key Kv is generated at random. The coding key may be generated based on a RSN, time stamp, etc. For example, the coding key Kv is a random number generated by the Voter Device 110, such as through a random number generator. Next, as shown in Line 8, the Voter Device 110 sends the VN to the Voting Station 120 using the following framework of the opinion registering application of the UPTF (voting device message view): DID, KUPTF,v(VN: Kv,UID,DID). The KUPTF,v is the encoding key for the encoded portion of the ballot generated by the Voter Device 110 according to UPTF. The encoded portion of the message generated at the Voter Device 110 is discussed in detail in the above-described embodiments of the present invention. The Voter Device 110 also sends the ballot encoded with Kv (MENCODED—BALLOT) to the Voting Station 120 using the following UPTF framework: Kv (Bf,VN),VN. Next, as shown in Line 9, the Voting Station 120 stores the VN in the local database according to predetermined criteria. For example, the VN may be stored according to whether it is “acknowledged” or “recounted.” The Voting Station 120 also stores the ballot encoded with Kv, e.g., Kv (Bf,VN),VN, in the local database. In addition, the Voting Station 120 sends the voter device message view (DID,KUPTF,v(VN: Kv,UID,DID)), along with a voting station message view generated by the Voting Station 120 (UID, KUPTF,vs (VN:,UID,DID)), to the STS 130. Next, as shown in Line 10, the STS 130 performs a matching operation with the voter device message view and the voting station message view. For example, when the VN matches the VN stored in the local database of the Voting Station 120, the STS 130 sends an encoded acknowledge message to the Voting Station 120 and a receipt with the VN to the Voter Device 110. Note, for example, that the receipt can be sent directly to the Voter Device 110 without first being sent to the Voting Station 120. Next, as shown in Line 11, the Voting Station 120 checks (classifies) the vote as “acknowledged” in the local database and sends a receipt indicating such to the Voter Device 110. The above described process, with respect to at least the transactions shown in Lines 1-10, is repeated until either all of the invited voters have voted or the time for voting expires, as determined by the Voting Master 140. In FIG. 6, the dashed line below Line 11 represents operations that occur when the time for voting expires. Next, as shown in Line 12, when the time for voting expires, the STS 130 a message to the Voting Master 140, including the coding key KV and the corresponding VN. Next, as shown in Line 13, the Voting Master 140 sends a message to the Voting Station 120 requesting the VN corresponding with the Voting Station 120. This is done for verification purposes to ensure that the proper voter has voted and that there has been no tampering with the ballot. Finally, as shown in Line 14, the Voting Station 120 sends a message to the Voting Master 140, including the encoded ballot stored in the local database and the coding key Kv (Kv (Bf,VN)). In addition, the Voting Station 120 may “acknowledge” the vote as recounted. As previously described, the acknowledgement may be done by a simple checking or classification procedure. According to the foregoing transactions, the Voting Master 140 cannot know which voter cast a particular vote, as the Voting Master 140 is only in possession of the coding key KV, the ballot, and the VN. None of this information supplies any information about the voter. After the Voting Master 140 receives the encoded ballot stored in the local database and the coding key Kv (Kv (Bf,VN)), the Voting Master 140 may proceed with performing a predetermined operation, such as counting the votes. In doing so, the Voting Master 140 may be in communication with the Voting Station 120 so that the Voting Station 120 may correct possible errors and/or further classify the votes as “Not acknowledged” and “Not recounted.” As discussed above, the present invention significantly broadens the scope of applications of the UPTF. In addition, there are many benefits provided by the opinion registering application using UPTF described in the embodiments of the present invention. For example, the voting station is relatively easy to set up, the voting equipment is inexpensive and less personnel is necessary for carrying out the voting process, the process is flexible and fast for voters, parallelization of the voting actions (simultaneous voting), there is no waiting in line, and voters are not limited to voting in any one particular voting station. According to another embodiment of the invention, the embodiments discussed above may be used in an e-government application. For example, this dual-purpose use of the UPTF framework would be beneficiary to the deployment of UPTF, especially by disseminating UPTD's in the hand of voters who also happen to be consumers. Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention is related to an opinion registering application in a Universal Pervasive Transaction Framework, an example of which is voting, and more particularly, to an application that requires a transaction to be multi-coded so that the identity of a user and the content of the transaction cannot both be known by any single device, other than the device in which the transaction is input, within or outside of the network. 2. Description of the Related Art Electronic-voting (“e-voting”) applications are well known in the art and have several desirable characteristics such as convenience of voting or opinion registering, non-human computation or tallying of votes, faster processing and voting times, and flexibility. However, e-voting, as with most Internet-type transaction, is prone to security violations, inaccuracy, and integrity issues. E-voting is not like any other electronic transaction. There are two main types of e-voting: polling place e-voting, and remote e-voting. Remote e-voting is the unsupervised use of an Internet voting device to cast a ballot over the Internet using a computer not necessarily owned and operated by election personnel. Authentication of the voter relies on computer security procedures, but includes some form of identity verification that is at least as secure as existing voting procedures. Remote e-voting is highly susceptible to voter fraud. Polling place e-voting is defined as the use of Internet Voting Machines at traditional polling places staffed by election officials who assist in the authentication of voters before ballots are cast. Several cryptography methods have been developed and/or are being used to ensure secrecy and security with regards to e-voting so that e-voting may be reliably used for voting in municipal, regional, or national elections. Essentially, a polling station computer confirms to a voter that a valid vote has been cast, and also provides a receipt. This paper receipt has an encoded code on it derived from a central computer. After the election, the voter can confirm that his/her vote was counted, for example, by checking a particular Web site to make sure that their receipt's sequence corresponds to those that have been posted, or asking an organization that they trust to do the verification. For instance, most polling place e-voting applications involve the following type of security: (1) the voter constructs an “anonymous electronic ballot”; (2) the voter shows adequate proof of identity to an election authority; (3) the election authority “stamps” the ballot after verifying that no other ballot has been stamped for this voter; and (4) the voter anonymously inserts the ballot into an electronic mail box. Current e-voting applications are not secure or reliable. Voters are often required to vote from specific e-voting type voting equipment. Voters are not able to vote wirelessly from a Universal Pervasive Transaction Device, such as a PDA or cell-phone, in a secure manner such that the voting action can be authenticated but without any third party or device knowing the content of the vote of that specific individual. Further, there is no way to ensure that the voting action transaction can transpire without any third party or device knowing the content of the vote of a particular voter. | <SOH> SUMMARY OF THE INVENTION <EOH>According to an aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, including a first device, where the content of the transaction is input and submitted to a second device, the second device encoding the content of the transaction that is input at the first device with a code key K Vsi sending the content of the transaction that is encoded with the code key K VSi to the first device, the first device generating a first message by further encoding the content of the transaction that is encoded with the code key K VSi with a respective UPTF-SAS key, and the second device generating a second device encoded message by further encoding the content of the transaction that is encoded with the code key K VSi with a respective UPTF-SAS key, a third device receiving the encoded messages of the first and the second device, decoding the received encoded messages to authenticate an identity of the user of the first device, matching the decoded messages to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction that is encoded with the code key K VS to a fourth device, and the fourth device receiving the encoded content of the transaction encoded with the code key K VSi and using the code key K VSi to determine content of the transaction input by the user of the first device. According to an aspect of the present invention, the second device and the fourth device agree on the code key K Vsi , or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key K VSi of the second device to decode the content of the transaction that is encoded with the code key K Vsi . According to an aspect of the present invention, the second device cannot determine the identity of the user that input the content of the transaction because when the content of the transaction is input at the first device and submitted to the second device, the first device does not transmit user identifying information to the second device, and because in the first message generated by the first device, the identity of the user is encoded by the first device according to a coding technique that can only be decoded by the third device. According to an aspect of the present invention, the third device cannot determine the content of the transaction input by the user but can determine whether a particular user input the content of the transaction at a particular second device, and the fourth device cannot determine the identity of the user that input the content of the transaction since the fourth device cannot determine the first device in which the content of the transaction was input by the user. According to an aspect of the present invention, the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF-SAS keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF-SAS coding keys, and the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. According to an aspect of the present invention, the user is authenticated to operate the first device according at least one biometric feature of the user or a personal identification number. According to an aspect of the present invention, the transaction of the computer system is performed between the first and the second device, the transaction is an opinion registering application, and the content of the transaction is a ballot. According to an aspect of the present invention, there is one or more first device and one or more second device. According to another aspect of the present invention, there is a virtual private network located between the second device and the fourth device and another virtual private network located between the third device and the fourth device. According to another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, including a first device generating an encoded message, including a user input content portion, according to UPTF, a second device further encoding the user input content portion of the encoded message with a coding key K VSi and generating a second device encoded message corresponding to the transaction according to UPTF, a third device receiving, decoding, and comparing the encoded messages of the first and second device to authenticate an identity of the user of the first device and to authenticate an occurrence of the transaction, and forwarding the encoded content of the transaction encoded with the code key K Vsi , and a fourth device receiving the encoded content of the transaction encoded with the code key K VSi and using the code. According to an aspect of the present invention, the coding algorithm used for further encoding the user input content portion of the encoded message with the coding key K Vsi is commutative with the algorithm used by the first device to generate the encoded message. According to an aspect of the present invention, the second device message does not include the user input content portion. According to an aspect of the present invention, the second device and the fourth device agree on the code key K Vsi , or a public key cryptographic key pair, prior the transaction being transmitted in the computer-based system, and the third device sends identifying information of the corresponding second device to the fourth device so that the fourth device can retrieve the code key K VSi of the second device to decode the user input content portion of the encoded message encoded with the coding key K Vsi . According to an aspect of the present invention, the third device cannot determine the user input content portion of the transaction, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction. According to an aspect of the present invention, the third device authenticates the identity of the user of the first device after successfully decoding the encoded messages of the first and second device by reconstructing the UPTF keys of each of the first and second devices since the third device knows the parameters of the coding algorithms used to produce the respective UPTF coding keys, and the occurrence of the transaction is authenticated by matching content of the successfully decoded messages of the first and second device according to a UPTF-SAS protocol. According to yet another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to the content of the transaction, including a first device receiving from a second device a reference number, which relates to a not yet input transaction, the first device generating a first encoded message after the transaction, which is a user input content portion, is input by the user at the first device, such that the first encoded message includes the user input content portion that is encoded with a random code key K V , the first device generating a second encoded message including, which includes the random code key K V and the reference number, and sending the first and second encoded messages to the second device, the second device storing the first encoded message, forwarding the second encoded message to a third device, and generating a third encoded message including the random code key K V and the reference number and not containing the user input content portion, the third device receiving the second and third encoded messages, which do not have the user input content portion, decoding the messages to authenticate an identity of the user and matching content of the second and third decoded messages to authenticate an occurrence of the transaction, and forwarding the code key K V and the reference number to a fourth device, and the fourth device receiving from the second device the first encoded message and the reference number, receiving from the third device the random code key K V and the reference number, and determining from the received information the user input content portion of the transaction input by the user. According to an aspect of the present invention, the first encoded message is stored in a database of the second device and is not sent to the fourth device to be decoded until the third device has verified the identity of the user and the occurrence of the transaction. According to an aspect of the present invention, the third device never receives the user input content portion of the transaction input by the user, and the fourth device cannot determine the identity of the user that input the user input content portion of the transaction. According to an aspect of the present invention, the user input content portion of the transaction is encoded whenever sent from the first device to any other device in the computer-based system, wherein the third device never receives the user input content portion of the transaction, and wherein there is an accounting for the transaction input by the user so that errors may be located. According to still another aspect of the present invention, there is provided a computer-based system securely transmitting and authenticating a transaction input by a user while retaining the anonymity of the user with respect to content of the transaction, including a device encoding the content of the transaction input by the user with a key known only to another device, encoding other portions of the transaction with another key known only to a secure transaction server, and sending the encoded content of the transaction and the encoded other portions of the transaction to the secure transaction server to authenticate an identity of the user of the device, wherein the secure transaction server decodes the other portions of the transaction and sends the encoded content of the transaction to the another device to be finally decoded. Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. | 20050125 | 20110125 | 20050915 | 63792.0 | 0 | SCHWARTZ, DARREN B | OPINION REGISTERING APPLICATION FOR A UNIVERSAL PERVASIVE TRANSACTION FRAMEWORK | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,231 | ACCEPTED | OFDM communication system and method | A transmitter (200) used in a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme includes a determination unit (216) configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission, a multiplexing unit (212) configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude, and means (214) configured to modulate the multiplexed signal in the OFDM scheme and transmit the modulated signal as OFDM symbols. | 1. A wireless communication system employing an orthogonal frequency division multiplexing (OFDM) scheme, including a transmitter and a receiver, wherein the transmitter comprises: a determination unit configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission; a multiplexing unit configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude; and means for modulating the multiplexed signal in the OFDM scheme and transmitting the modulated signal as OFDM symbols; and wherein the receiver includes means for demodulating the OFDM symbols and despreading the demodulated symbols to extract the control channel. 2. A transmitter used in a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme, comprising: a determination unit configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission; a multiplexing unit configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude; and means for modulating the multiplexed signal in the OFDM scheme and transmitting the modulated signal as OFDM symbols. 3. The transmitter of claim 2, further comprising: a spreading unit configured to code-spread the control channel in a multi-carrier code division multiple access (MC-CDMA) scheme. 4. The transmitter of claim 2, further comprising: a spreading unit configured to code-spread the control channel in a direct sequence-code division multiple access (DS-CDMA) scheme. 5. The transmitter of claim 2, being applied to a wireless base station in an isolated cell. 6. The transmitter of claim 2, wherein the determination unit controls the spreading factor and the amplitude such that the influence of the control channel on the data channel is smaller than a prescribed level. 7. The transmitter of claim 6, wherein information representing the spreading factor and the amplitude of the code-spread control channel is transmitted. 8. A receiver used in a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme, comprising: a detection unit configured to detect a spreading factor and a channel type from a received signal, the received signal being a data channel and a control channel multiplexed together; and control channel recovery means for recovering the control channel from the received signal based on the spreading factor and the channel type. 9. A wireless communication method based on an orthogonal frequency division multiplexing (OFDM) scheme comprising the steps of: determining a spreading factor and an amplitude for a control channel to be transmitted based on signal quality information and interference level in data transmission; multiplexing a data channel with a control channel having been code-spread using the determined spreading factor and amplitude; modulating the multiplexed signal in the OFDM scheme; transmitting the modulated signal; demodulating the transmitted signal in the OFDM scheme at a receiver; and despreading the demodulated signal to extract the control channel. | FIELD OF THE INVENTION The present invention generally relates to wireless communication, and more particularly, to an orthogonal frequency division multiplexing (OFDM) transmission technique and a transmitter and a receiver used in OFDM communication. BACKGROUND OF THE INVENITON OFDM transmission is a promising access scheme in the field of wireless communication because of the advantageous features in the multipath propagation environment. In OFDM transmission, a data channel (or a sequence of symbols) to be transmitted is associated with multiple subcarriers selected so as to be orthogonal to each other, and is subjected to inverse Fourier transform and application of a guard interval, prior to being transmitted as OFDM symbols. At the receiving end, the guard interval is removed from the received signal, and Fourier transform is performed to extract information from each of the subcarriers. Then, the transmitted data channel is recovered. The wireless receiver receives a control channel, as well as the data channel. The control channel includes a pilot channel containing priori known symbols, a common control channel used to transmit common information to all wireless receivers in the system, and an individual control channel used to transmit an individual data item to a wireless receiver. Dedicated resources are allocated to the control channel, which control channel is multiplexed with the OFDM symbols transmitted from the wireless transmitter. The wireless receiver extracts the control channel, including the pilot channel, from the received OFDM symbols, and performs channel estimation and securing of synchronization timing. This type of wireless transmission using an OFDM scheme is described in JP 2001-144724A. FIG. 1A and FIG. 1B are schematic diagrams illustrating a control channel multiplexed with a data channel. In FIG. 1A, the control channel is frequency-multiplexed with the data channel by allocating a certain band of the spectrum. In FIG. 1B, the control channel is time-multiplexed with the data channel by allocating a certain time slot to the pilot channel. It will be more and more required for this field of technology to catch up with the increasing moving speed of mobile terminals, expansion of the available frequency band, and shift to higher ranges of frequency, from the viewpoint of providing high-quality services. Accordingly, it is required to provide communication services capable of sufficiently meeting a rapid change in the signal level along the time and frequency axes occurring in the communication environment. As illustrated in FIG. 1A and FIG. 1B, a control channel (such as a pilot channel) is inserted only in a specific domain along the frequency axis or the time axis. For this reason, if the signal level abruptly changes in a domain in which the pilot channel is not inserted, satisfactory channel estimation cannot be performed. In this case, the function and the objective of the pilot channel cannot be achieved sufficiently. This means that the resources allocated to that control channel are not being efficiently used. In addition, since dedicated resources are allocated to the control channel, the resources to be allocated to the data channel decreases. If the resources dedicatedly allocated to the control channel cannot be used efficiently, allocating the dedicated resources to the control channel, while decreasing the resources to be allocated to the other channels, becomes meaningless. SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to solve the above-described problems in the prior art, and to provide an OFDM wireless transmission technique capable of achieving efficient use of the resources allocated to the data channel and the control channel. In the present invention, a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme is provided. The system includes a transmitter and a receiver. In one aspect of the invention, a transmitter used in the FODM communication system comprises: (a) a determination unit configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission; (b) a multiplexing unit configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude; and (c) means configured to modulate the multiplexed signal in the OFDM scheme and transmit the modulated signal as OFDM symbols. In a preferred example, the transmitter further includes a spreading unit configured to code-spread the control channel in a multi-carrier code division multiple access (MC-CDMA) scheme. With this example, the control channel is inserted continuously over a wide range of the frequency domain, and consequently, channel estimation can be performed correctly over the entire range even if an abrupt change in signal level occurs in the frequency domain. In another example, the transmitter further includes a spreading unit configured to code-spread the control channel in a direct sequence-code division multiple access (DS-CDMA) scheme. With this example, the control channel is inserted continuously over the entire frame in the time domain, and consequently, channel estimation can be correctly performed even if an abrupt change in signal level occurs in the time domain. In still another example, the transmitter is applied to a wireless base station in an isolated cell. In the isolated cell, transmitting the data channel without code spreading, while transmitting the code-spread control channel, becomes advantageous. In yet another example, the determination unit regulates the spreading factor and the amplitude such that the influence of the control channel on the data channel is smaller than a prescribed level. With this arrangement, the code-spread control channel can be multiplexed with the data channel so as not to prevent recovery of the data channel. In yet another example, information representing the spreading factor and the amplitude of the code-spread control channel is transmitted to a receiver. This arrangement allows the receiver to recover the control channel promptly from the received signal. BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features, and advantages of the invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which FIG. 1A and FIG. 1B are schematic diagrams illustrating a pilot channel multiplexed with a data channel; FIG. 2 is a block diagram of a wireless transmitter used in an OFDM communication system according to the first embodiment of the invention; FIG. 3 is a block diagram of the two-dimensional spreading unit used in the wireless transmitter shown in FIG. 2; FIG. 4 is a block diagram of a wireless receiver used in the OFDM communication system according to the first embodiment of the invention; FIG. 5 is a block diagram of the two-dimensional despreading unit used in the wireless receiver shown in FIG. 4; FIG. 6A and FIG. 6B are schematic diagrams illustrating the relation between the data channel and the control channel according to an embodiment of the invention; FIG. 7 is a block diagram of a wireless transmitter used in the OFDM communication system according to the second embodiment of the invention; FIG. 8 is a block diagram of a wireless receiver used in the OFDM communication system according to the second embodiment of the invention; FIG. 9 is a flowchart of a wireless communication method according to an embodiment of the invention; FIG. 10 is a block diagram of the spreading factor and amplitude determination unit used in the wireless transmitter; and FIG. 11 is a schematic diagram illustrating the relation between the transmit power of the data channel and that of the control channel before and after multiplexing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is described in detail below in conjunction with the attached drawings. It should be noted that the attached drawings depict those components relating to the present invention, among various functional elements structuring a wireless transmitter and a wireless receiver used in OFDM transmission. FIG. 2 is a block diagram of a wireless transmitter 200 used in an OFDM communication system according to the first embodiment of the invention. The wireless transmitter 200 has a channel encoder 202, a data modulator 204, serial to parallel converters (S/P converters) 206 and 208, a two-dimensional spreading unit 210, a control channel multiplexing unit 212, an inverse fast Fourier transform (IFFT) unit 214, a spreading factor and amplitude determination unit 216, a spreading factor control unit 218, and an amplitude control unit 220. The channel encoder 202 receives a bit stream representing the contents of data, which is to be transmitted by the user in OFDM symbols, and performs appropriate coding on the received bit stream. An example of the coding is error correction coding, such as convolution coding or turbo coding. The data modulator 204 modulates the appropriately encoded bit stream using a prescribed modulation scheme. Any suitable modulation scheme, such as QPSK, 16-level quadrature amplitude modulation (16 QAM), or 64-level quadrature amplitude modulation (64 QAM), may be used. The first serial to parallel converter 206 converts a serial modulated bit stream of the user data into parallel bit streams. For the purpose of simplification, the number of parallel bit streams of the user data equals the number Nc of the subcarriers in this embodiment; however, the invention is not limited to this example. The parallel bit streams are supplied to the control channel multiplexing unit 212. The second serial to parallel converter 208 converts a serial control bit stream representing a control channel (e.g., a pilot channel) into parallel control bit streams. For the purpose of simplification, the number of the parallel control bit streams equals a number (Nc/SF) obtained by dividing the number Nc of the subcarriers by the code spreading factor SF; however, the invention is not limited to this example. The two-dimensional spreading unit 210 multiplies the parallel control bit streams by a spreading code. FIG. 3 is a block diagram of the two-dimensional spreading unit 210 used in the wireless transmitter 200 shown in FIG. 2. The two-dimensional spreading unit 210 performs code spreading using a Multi-Carrier Code Division Multiple Access (MC-CDMA) scheme. The two-dimensional spreading unit 210 includes symbol copying units 302 corresponding to the parallel bit streams, a spreading code generator 304, and spreading code multipliers 306. MC-CDMA is also referred to as OFCDM (Orthogonal Frequency and Code Division Multiplexing). Each of the symbol copying units 302 produces a prescribed number (equal to the spreading factor SF, for example) of parallel control bit streams from one of the parallel bit streams supplied from the second S/P converter 208. Each of the copied control bit streams output from the symbol copying unit 302 is connected to one of the input terminals of the associated spreading code multiplier 306. A spreading code generated by the spreading code generator 304 is supplied to the other input terminal of each of the spreading code multipliers 306. Each of the spreading code multipliers 306 multiplies the control bit streams by the spreading code to perform code spreading on the control bit stream. The amplitude level of the code-spread control bit stream is appropriately regulated at the multiplier 222, and the amplitude-adjusted bit stream is supplied to the control channel multiplexing unit 212. Returning to FIG. 2, the spreading factor and amplitude determination unit 216 acquires, monitors, or estimates information about the signal quality required in the current wireless communication, the interference level of the data channel due to the control channel, and other necessary information. Based on the acquired information, the spreading factor and the amplitude for the control channel are determined, and the determination results are supplied to the spreading code control unit 218 and the amplitude control unit 220, respectively. FIG. 10 is a block diagram of the spreading factor and amplitude determination unit 216. The spreading factor and amplitude determination unit 216 includes a control channel transmit power determination unit 1002, a spreading factor determination unit 1004, and an amplitude determination unit 1006. The control channel transmit power determination unit 1002 determines a transmit power Pcontrol, which power is assigned to a non-spread control channel when the non-spread control channel is to be transmitted. This transmit power corresponds to the power of the output signal from the two-dimensional spreading nit 210 shown in FIG. 2, and is determined based on the feedback information supplied from a wireless receiver, as will be described below. The feedback information includes the signal quality (such as SINR) of the signal received at the wireless receiver, and the interference level of the data channel due to the control channel. The transmit power Pcontrol of the control channel may be calculated from formula (1). P control > α * [ ( interference level in data channel ) + ( noise component ) ] ( 1 ) where the noise component is estimated from the SINR of the receiving end, and α is a prescribed scaling factor having a fixed value. The calculated transmit power Pcontrol is supplied to the spreading factor determination unit 1004. The spreading factor determination unit 1004 determines the spreading factor SF such that the ratio of the transmit power (Pcontrol/SF) of the spread control channel to the data channel transmit power Pdata does not exceed a prescribed threshold value Th. The threshold value Th may be a fixed values, or a variable value dynamically determined based on the received SINR contained in the feedback information. This relation is expressed as (Pcontrol/SF)/Pdata<Th. (2) The calculated spreading factor is supplied to the amplitude determination unit 1006 and the spreading factor control unit 218 shown in FIG. 2. The amplitude determination unit 1006 determines the amplitude Acontrol so as to realize transmit power (Pcontrol/SF) of the post-spreading control channel determined according to expression (2). In general, the power of a signal is in proportion to the square of the amplitude, and therefore, the amplitude may be determined from Acontrol=(Pcontrol/SF)1/2. (3) The determined amplitude is supplied to the amplitude control unit 220. FIG. 11 schematically illustrates the relation between the control channel transmit power Pcontrol and the data channel transmit Pdata before and after spreading. In this embodiment, the control channel is inserted in a continuous manner along the frequency axis. In FIG. 11, the vertical axis corresponds to power, and the horizontal axis corresponds to frequency. By setting the power level of each channel in the above-described manner, the interference influence on the data channel due to the control channel can be maintained below the threshold Th. Returning again to FIG. 2, the spreading factor control unit 218 generates a control signal for setting an appropriate spreading factor based on the information supplied from the spreading factor and amplitude determination unit 216, and supplies the control signal to the two-dimensional spreading unit 210 (more specifically, to the symbol copying units 302). A target value of the spreading factor SF (“target SF”) is input to the spreading factor control unit 218, and the control signal is generated so as to realize the target SF. The amplitude control unit 220 generates a control signal for setting an appropriate amplitude level or power level based on the information supplied from the spreading factor and amplitude determination unit 216, and supplies the control signal to the multiplier 222. A target Acontrol is supplied to the amplitude control unit 220, and the control signal is generated so as to realize the target Acontrol. The control channel multiplexing unit 212 adds parallel bit streams of user data supplied from the first serial to parallel converter 206 to the code-spread parallel bit streams of the control channel for the respective subcarriers, and outputs Nc bit streams. The Nc bit streams comprise corresponding multiplexed user data and code-spread bit streams of the control channel. The inverse fast Fourier transform (IFFT) unit 214 performs inverse fast Fourier transform on the Nc bit streams to convert the information associated with the subcarriers to time-domain bit streams. The time-domain bit streams are supplied to the RF unit (not shown) that includes a band-limiting processing unit, a frequency converter, and a power amplifier, and transmitted from an antenna. FIG. 4 is a block diagram of a wireless receiver 400 used in the OFDM communication system according to the first embodiment of the invention. The wireless receiver 400 has a symbol timing synchronizing unit 402, a guard interval removing unit 404, a fast Fourier transform (FFT) unit 406, a spreading factor and channel type detection unit 408, and a two-dimensional despreading unit 410. The symbol timing synchronizing unit 402 takes synchronization based on the received OFDM symbols to guarantee appropriate timing. The guard interval removing unit 404 removes the guard interval from the received OFDM symbols, and extracts the subsequent remaining portion. The fast Fourier transform unit 406 performs fast Fourier transform, and outputs information having been transmitted on the respective subcarriers. Then, appropriate processes are carried out (by those components not shown in FIG. 4) to recover the transmitted information. The two-dimensional despreading unit 410 multiplies the Fourier-transformed parallel bit streams by an appropriate spreading code to despread the received bit streams. In this case, the spreading factor and channel type detection unit 408 supplies information about the spreading factor of the spreading code to the two-dimensional dispreading unit 410, and determines what types of code-spread information are currently being processed. For example, only a pilot channel may be code-spread in the control channel, and the other channels may be transmitted using another scheme, without spreading. The information about the spreading factor and the channel type is acquired from the wireless transmitter. FIG. 5 is a block diagram of the two-dimensional despreading unit 410. The two-dimensional despreading unit 410 performs despreading based on the MC-CDMA scheme, and includes a spreading code generator 502, spreading code multipliers 504, and symbol combining units 506. Each of the bit streams supplied from the FFT unit 406, the number of which streams equals, for example, the number Nc of subcarriers, is supplied to one of the input terminals of one of the spreading code multipliers 504. A spreading code generated by the spreading code generator 502 is supplied to the other input of the multipliers 504. Each of the spreading code multipliers 504 multiplies the associated bit stream by the spreading code to extract the control bit stream through despreading. Each of the symbol combining units 506 combines the prescribed number of bit streams (corresponding to the spreading factor SF, for example) into a bit stream. Then, the control channel is recovered through the subsequent processes (not shown). FIG. 9 is a flowchart showing the multiplexing and separation of the control channel and the data channel according to the embodiment of the invention. The data channel is a bit stream of data containing ordinary OFDM symbols, and the control channel is a code-spread bit stream based on the MC-CDMA scheme. The control channel and the data channel are added to each other by the control channel multiplexing unit 212 of the wireless transmitter 200 (step 904). The multiplexed (or added) signal is modulated by the IFFT unit 214, subjected to application of a guard interval, and transmitted as OFDM symbols from the antenna (step 906). Since the control channel has been code-spread, the spectrum of the multiplexed signal in the frequency domain becomes as shown in FIG. 6A. This spectrum is greatly different from that shown in FIG. 1A illustrating the conventional multiplexing of the data channel and the non-spread control channel. The wireless receiver 400 identifies the control channel and the data channel from the received signal, and recovers these channels (step 908). When recovering the data channel at the wireless receiver, the control channel is treated as noise. Because the noise has a low amplitude level over a wide range of the frequency domain, as illustrated in FIG. 6A, the recovery of the data channel is not prevented by the noise. In other words, the spreading factor and amplitude determination unit 216 of the wireless transmitter 200 determines the spreading factor SF and the amplitude Acontrol for the control channel to be transmitted such that the code-spread control channel does not prevent recovery of the data channel. The determined values are reported to the spreading factor control unit 218 and the amplitude control unit 220, respectively, so as to appropriately regulate the spreading factor SF and the amplitude Pcontrol (or the transmit power) for the channel currently being processed. The information about the spreading factor may be transmitted to the wireless receiver 400 via a non-coded channel, such as a broadcast control channel, by using a part of the data channel, or by any suitable means, as long as information required for recovery of the transmitted information can be used by the wireless receiver 400. Because the control channel is inserted over the entire range of the frequency domain, an instantaneously changing signal due to an abrupt change in amplitude level along the frequency axis or fading can be followed accurately over the entire range. In addition, since the control channel can be distinguished from the data channel based on whether the channel is spread by a spreading code, it is unnecessary to allocate a dedicated channel to the control channel. Consequently, the resources that have been allocated exclusively to the control channel in the conventional technique can be assigned to the data channel. Within the control channel, only the pilot channel may be code-spread. FIG. 7 is a block diagram of a wireless transmitter 700 used in the OFDM communication system according to the second embodiment of the invention. The wireless transmitter 700 has a channel encoder 702, a data modulator 704, a serial to parallel converter (S/P converter) 706, an inverse fast Fourier transform (IFFT) unit 708, a spreading unit 710, a control channel multiplexing unit 712, a spreading factor and amplitude determination unit 716, a spreading factor control unit 718, an amplitude control unit 720, and a multiplier 722. The channel encoder 702 receives a bit stream representing the contents of data, which is to be transmitted by the user in OFDM symbols, and performs appropriate coding on the received bit stream. An example of the coding is error correction coding, such as convolution coding or turbo coding. The data modulator 704 modulates the appropriately encoded bit stream using a prescribed modulation scheme. The serial to parallel converter 706 converts a serial modulated bit stream of the user data into as many parallel bit streams as the number Nc of the subcarriers. The parallel bit streams are supplied to the IFFT unit 708. The IFFT unit 708 performs inverse fast Fourier transform on Nc bit streams to convert the user data to be carried on the subcarriers into time-domain bit streams. The time-domain bit streams are supplied to the control channel multiplexing unit 712. The spreading unit 710 multiplies the control bit stream by a spreading code. The spreading unit 710 performs code spreading using a Direct Sequence-Code Division Multiple Access (DS-CDMA) scheme. The spreading unit 710 includes a spreading code generator (not shown) and a spreading code multiplier (not shown). The code-spread control bit stream is supplied to the multiplier 722 for appropriate adjustment of the amplitude level, and then input to the control channel multiplexing unit 712. The spreading factor and amplitude determination unit 716 acquires, monitors, or estimates information about the signal quality required in the current wireless communication, the interference level in the data channel due to the control channel, and other necessary information. The spreading factor and the amplitude of the control channel determined based on the acquired information are supplied to the spreading code control unit 718 and the amplitude control unit 720, respectively. The spreading factor and amplitude determination unit 716 may have the same structure as that described in the first embodiment with reference to FIG. 10. However, in the second embodiment, the control channel is inserted continuously along the time axis, unlike the first embodiment in which the control channel is inserted along the frequency axis. The spreading factor control unit 718 generates a control signal for setting an appropriate spreading factor based on the information supplied from the spreading factor and amplitude determination unit 716, and supplies the control signal to the spreading unit 710. The amplitude control unit 720 generates a control signal for setting an appropriate amplitude level or power level based on the information supplied from the spreading factor and amplitude determination unit 716, and supplies the control signal to the multiplier 722. The control channel multiplexing unit 712 adds the parallel bit streams of user data supplied from the IFFT unit 708 to the code-spread bit stream of the control channel, and outputs a multiplexed bit stream combining user data stream with the spread control bit stream. This bit stream is then subjected to application of a guard interval, supplied to an RF unit (not shown) that includes a band-limiting processing unit, a frequency converter, and a power amplifier, and transmitted from the antenna. FIG. 8 is a block diagram of a wireless receiver 800 used in the OFDM communication system according to the second embodiment of the invention. The wireless receiver 800 has a symbol timing synchronizing unit 802, a guard interval removing unit 804, a fast Fourier transform (FFT) unit 806, a rake combining unit 808, a path search unit 810, a channel estimation unit 812, and a spreading factor and channel type detection unit 814. The symbol timing synchronizing unit 802 takes synchronization based on the received OFDM symbols to guarantee appropriate timing. The guard interval removing unit 804 removes the guard interval from the received OFDM symbols, and extract the subsequent remaining portion. The fast Fourier transform (FFT) unit 806 performs fast Fourier transform, and outputs information having been transmitted on the respective subcarriers. Then, appropriate processes are carried out (by those components not shown in FIG. 8) to recover the transmitted information. The received OFDM symbols are also input to the rake combining unit 808 and the path search unit 810. The path search unit 810 detects timings of multiple propagation paths of the received OFDM symbols. The channel estimation unit 812 supplies a control signal for compensating for fading fluctuation in each path to the rake combining unit 808. The spreading factor and channel type detection unit 814 supplies information about the spreading factor of the spreading code to the rake combining unit 808, and determines what types of code-spread information are currently being processed. The rake combining unit 808 combines the signals from the respective multiple paths, while compensating for the influence of fading on each path based on the control signal. As a result, an appropriately despread control bit stream can be obtained for the control channel. Based on the control bit stream, the control channel transmitted from the wireless transmitter 700 is recovered by the subsequent components (not shown). Next, explanation is made of multiplexing and separation of the control channel and the data channel. The basic procedure is the same as that already explained in conjunction with FIG. 9. In the second embodiment, the data channel is a bit stream of user data containing ordinary OFDM symbols, while the control channel is a code-spread bit stream based on a DS-CDMA scheme. The data channel and the control channel are added to each other at the control channel multiplexing unit 712. The multiplexed bit stream is subjected to application of a guard interval, and transmitted as OFDM symbols from the antenna. Since the control channel is code-spread in the time domain, the time-domain spectrum of the signal to be transmitted becomes as shown in FIG. 6B, which is greatly different the time-domain spectrum of the conventional technique shown in FIG. 1B. When recovering the data channel at the wireless receiver 800, the control channel is treated as noise. The noise has a low amplitude level over the entire section of the frame, as illustrated in FIG. 6B, and accordingly, recovery of the data channel is not prevented by the noise. In other words, the spreading factor control unit 718 and the amplitude control unit 720 appropriately adjust the spreading factor and the amplitude (or the power) such that the control channel does not prevent recovery of the data channel. In the second embodiment, the control channel is inserted continuously over the entire frame of the time domain. (In the first embodiment, the control channel is inserted continuously over the entire range of the frequency domain.) An instantaneously changing signal due to an abrupt change in amplitude level along the time axis or fading can be followed accurately over the entire frame. In addition, because the control channel can be distinguished from the data channel based on whether the channel is spread by a spreading code, it is unnecessary to allocate a dedicated channel to the control channel. Consequently, the resources that have been allocated exclusively to the control channel in the conventional technique can be assigned to the data channel. Within the control channel, only the pilot channel may be code-spread. In the first and second embodiments (for spreading the control channel in the frequency domain and the time domain, respectively), it is also technically possible to spread the data channel. Such an arrangement is advantageous when a number of cells define a wide range of a service area. With a CDMA scheme, all the signals not addressed to own station become noise. Such noise includes interference within the cell and interference from adjacent cells. If the data channel is being code-spread, interference form adjacent cells can be reduced efficiently during extraction of the data channel. Accordingly, in such a communication environment, spreading of the data channel is advantageous. However, there are some environments in which interference from other cells does not have to be considered. For example, a cell or a service area is provided as a spot or an isolated cell. If the data channel is spread in such an environment, interference within the cell increases due to interference between the spreading code of the control channel and the spreading code of the data channel. This may result in an undesirable limitation of resources for the data channel. Accordingly, it is advantageous for a wireless communication system defining isolated cells to transmit the data channel as ordinary OFDM symbols, without code spreading, while spreading the control channel. The wireless transmitter described in the first and second embodiments can be advantageously applied to a wireless base station of an isolated cell so as to allow the data channel to be multiplexed with a code-spread pilot channel. This patent application is based on and claims the benefit of the earlier filing dates of Japanese Patent Application No. 2004-018772 filed Jan. 27, 2004, the entire contents of which are hereby incorporated by reference. | <SOH> BACKGROUND OF THE INVENITON <EOH>OFDM transmission is a promising access scheme in the field of wireless communication because of the advantageous features in the multipath propagation environment. In OFDM transmission, a data channel (or a sequence of symbols) to be transmitted is associated with multiple subcarriers selected so as to be orthogonal to each other, and is subjected to inverse Fourier transform and application of a guard interval, prior to being transmitted as OFDM symbols. At the receiving end, the guard interval is removed from the received signal, and Fourier transform is performed to extract information from each of the subcarriers. Then, the transmitted data channel is recovered. The wireless receiver receives a control channel, as well as the data channel. The control channel includes a pilot channel containing priori known symbols, a common control channel used to transmit common information to all wireless receivers in the system, and an individual control channel used to transmit an individual data item to a wireless receiver. Dedicated resources are allocated to the control channel, which control channel is multiplexed with the OFDM symbols transmitted from the wireless transmitter. The wireless receiver extracts the control channel, including the pilot channel, from the received OFDM symbols, and performs channel estimation and securing of synchronization timing. This type of wireless transmission using an OFDM scheme is described in JP 2001-144724A. FIG. 1A and FIG. 1B are schematic diagrams illustrating a control channel multiplexed with a data channel. In FIG. 1A , the control channel is frequency-multiplexed with the data channel by allocating a certain band of the spectrum. In FIG. 1B , the control channel is time-multiplexed with the data channel by allocating a certain time slot to the pilot channel. It will be more and more required for this field of technology to catch up with the increasing moving speed of mobile terminals, expansion of the available frequency band, and shift to higher ranges of frequency, from the viewpoint of providing high-quality services. Accordingly, it is required to provide communication services capable of sufficiently meeting a rapid change in the signal level along the time and frequency axes occurring in the communication environment. As illustrated in FIG. 1A and FIG. 1B , a control channel (such as a pilot channel) is inserted only in a specific domain along the frequency axis or the time axis. For this reason, if the signal level abruptly changes in a domain in which the pilot channel is not inserted, satisfactory channel estimation cannot be performed. In this case, the function and the objective of the pilot channel cannot be achieved sufficiently. This means that the resources allocated to that control channel are not being efficiently used. In addition, since dedicated resources are allocated to the control channel, the resources to be allocated to the data channel decreases. If the resources dedicatedly allocated to the control channel cannot be used efficiently, allocating the dedicated resources to the control channel, while decreasing the resources to be allocated to the other channels, becomes meaningless. | <SOH> SUMMARY OF THE INVENTION <EOH>Therefore, it is an object of the present invention to solve the above-described problems in the prior art, and to provide an OFDM wireless transmission technique capable of achieving efficient use of the resources allocated to the data channel and the control channel. In the present invention, a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme is provided. The system includes a transmitter and a receiver. In one aspect of the invention, a transmitter used in the FODM communication system comprises: (a) a determination unit configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission; (b) a multiplexing unit configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude; and (c) means configured to modulate the multiplexed signal in the OFDM scheme and transmit the modulated signal as OFDM symbols. In a preferred example, the transmitter further includes a spreading unit configured to code-spread the control channel in a multi-carrier code division multiple access (MC-CDMA) scheme. With this example, the control channel is inserted continuously over a wide range of the frequency domain, and consequently, channel estimation can be performed correctly over the entire range even if an abrupt change in signal level occurs in the frequency domain. In another example, the transmitter further includes a spreading unit configured to code-spread the control channel in a direct sequence-code division multiple access (DS-CDMA) scheme. With this example, the control channel is inserted continuously over the entire frame in the time domain, and consequently, channel estimation can be correctly performed even if an abrupt change in signal level occurs in the time domain. In still another example, the transmitter is applied to a wireless base station in an isolated cell. In the isolated cell, transmitting the data channel without code spreading, while transmitting the code-spread control channel, becomes advantageous. In yet another example, the determination unit regulates the spreading factor and the amplitude such that the influence of the control channel on the data channel is smaller than a prescribed level. With this arrangement, the code-spread control channel can be multiplexed with the data channel so as not to prevent recovery of the data channel. In yet another example, information representing the spreading factor and the amplitude of the code-spread control channel is transmitted to a receiver. This arrangement allows the receiver to recover the control channel promptly from the received signal. | 20050125 | 20080708 | 20050825 | 60240.0 | 0 | BOCURE, TESFALDET | OFDM COMMUNICATION SYSTEM AND METHOD | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,315 | ACCEPTED | Circuit arrangement for monitoring a voltage supply, and for reliable locking of signal levels when the voltage supply is below normal | A circuit arrangement for monitoring an external voltage supply (VBAT1, VBAT2) and for reliable locking of a signal (Z2), which is emitted from a logic circuit (8), at a voltage level (VDD, VSS) of an internal voltage supply, wherein the circuit arrangement has a voltage divider (6, 7), which is connected between a first and a second external supply voltage (VBAT1, VBAT2) and produces a potential level (VLOCK) for a switching signal; a controllable switch (13) which separates the internal voltage supply, which has a first and a second internal supply voltage (VDD, VSS), from the logic circuit (8) in order to deactivate the latter as a function of a locking signal (LOCKP) which is produced from the switching signal; and a high-value resistor (14) by means of which the signal (Z2) which is emitted from the deactivated logic circuit (8) is drawn to the level of one of the two internal supply voltages (VSS). | 1. Circuit arrangement for monitoring an external voltage supply and for reliable locking of a signal, which is emitted from a logic circuit, at a voltage level of an internal voltage supply, having: (a) a voltage divider, which is connected between a first and a second external supply voltage and produces a potential level for a switching signal; (b) a controllable switch which separates the internal voltage supply, which has a first and a second internal supply voltage, from the logic circuit in order to deactivate the latter as a function of a locking signal which is produced from the switching signal, and (c) a high-value resistor by means of which the signal which is emitted from the deactivated logic circuit is drawn to the level of one of the two internal supply voltages. 2. Circuit arrangement according to claim 1, wherein the logic circuit processes an input signal, which is referenced to the external supply voltages, and the voltage divider is designed such that the locking signal deactivates the logic circuit before the level or levels of the input signal becomes or become unacceptable in the event of a drop in the external supply voltages. 3. Circuit arrangement according to claim 1, wherein (a) a monitoring circuit is provided, which has a first supply voltage connection for application of the first external supply voltage, a second supply voltage connection for application of the second external supply voltage, and at least one output for emission of the locking signal, wherein at least two resistors are connected as a voltage divider between the supply voltage connections, and the locking signal is produced as a function of a voltage potential which can be tapped off between the resistors; (b) the logic circuit has a first supply voltage connection and a second supply voltage connection for application of the second internal supply voltage, a control signal input for the input signal, and an output for the signal produced by the logic circuit; (c) the controllable switch is provided between the first internal supply voltage and the first supply voltage connection of the logic circuit, and the controllable switch connects the first internal supply voltage to the first supply voltage connection of the logic circuit as a function of the locking signal; and (d) the high-value resistor is connected between the output of the logic circuit and the second internal supply voltage. 4. Circuit arrangement according to claim 1, wherein the internal and external first supply voltages and the internal and external second supply voltages are each at the same voltage level. 5. Circuit arrangement according to claim 1, wherein the monitoring circuit (a) has a third supply voltage connection for application of the first internal supply voltage, and has a fourth supply voltage connection for application of the second internal supply voltage; (b) has a third resistor, a first MOS transistor with a controllable path and a gate connection, and a second MOS transistor with a controllable path and a gate connection, wherein the third resistor and the two controllable paths are connected in series between the two internal supply voltages and the switching signal is connected to the gate connection of the second MOS transistor, (c) has a complementary MOS transistor with a controllable path and a gate connection, and has a fourth resistor, wherein the controllable path through the complementary MOS transistor and the fourth resistor are connected in series between the two internal supply voltages, the gate connection of the complementary MOS transistor is connected to a potential node between the third resistor and the controllable path through the first MOS transistor, and the gate connection of the first MOS transistor is connected between the controllable path through the complementary MOS transistor and the fourth resistor; and (d) has a third MOS transistor with a controllable path and a gate connection, wherein the controllable path through the third MOS transistor is connected between the gate connection of the complementary MOS transistor and the second internal supply voltage, and the switching signal is connected to the gate connection of the third MOS transistor; and wherein (e) a first locking signal can be tapped off at the gate connection of the complementary MOS transistor, and a second locking signal can be tapped off at the gate connection of the first MOS transistor. 6. Circuit arrangement according to claim 5, wherein the monitoring circuit has a first and a second MOS control transistor, each having a controllable path and a gate connection, wherein the controllable path through the first MOS control transistor is connected between the controllable path through the first and through the second MOS transistor, the controllable path through the second MOS control transistor is connected between the gate connection of the complementary MOS transistor and the controllable path through the third MOS transistor, and wherein an external control signal is applied to the gate connections of the two MOS control transistors. 7. Circuit arrangement according to claim 1, wherein the controllable switch has an MOS switching transistor with a controllable path and a gate connection, wherein the locking signal is connected to the gate connection of the MOS switching transistor, and the controllable path through the MOS switching transistor is connected between one of the internal supply voltages and a supply voltage connection of the logic circuit. 8. Circuit arrangement according to claim 1, wherein the logic circuit has an inverter as the output driver. 9. Circuit arrangement according to claim 1, wherein the circuit arrangement is designed using a first MOS technology, and the control signals from the logic circuits drive circuits which are designed using a second technology. 10. Circuit arrangement according to claim 8, wherein the first technology operates at higher supply voltages than the second technology. | Circuit arrangement for monitoring a voltage supply, and for reliable locking of signal levels when the voltage supply is below normal The invention relates to a circuit arrangement for monitoring an external voltage supply and for reliable locking of a signal which is emitted from a logic circuit at a voltage level of an internal secondary voltage supply. Most mobile electronic applications include a battery or a rechargeable battery for supplying current and voltage. During operation, this external supply voltage decreases down to a complete discharge level, or else the external supply voltage even collapses completely when the user replaces the rechargeable battery. Electronic, mobile applications such as mobile telephones or electronic notebooks such as PDAs (Personal Digital Assistants) also often have to provide at least rudimentary functions even when the battery is discharged. For this purpose, a second back-up battery or a large buffer capacitor is generally provided, which produces an internal supply voltage for a limited time period. This auxiliary supply voltage may fall to very low values which are well below the nominal supply voltages for the circuits that are used in the electronic appliance. Appliance electronics typically include a large number of integrated circuits, which are designed using different technologies. Those integrated circuits which have to provide the rudimentary functions are then designed, for example, using a particularly power-saving technology (for example CMOS technology), so that the functions, for example a real time clock, operate even when the secondary voltage supply is at an extreme level. These circuits which provide rudimentary functions are designed as circuits which require low voltages. If the external supply voltage decreases as a result of discharging or removal of the rechargeable battery, it is necessary to reliably generate reset signals or other control signals which indicate to the low-voltage circuits that only rudimentary operation should be provided by the battery during the failure of the main power supply or voltage supply. In this case, it is important for the circuits which produce the reset signals to produce reliable, logic levels for the reset signal or control signal bearing in mind the changing, very low supply voltage. Without special measures, the logic levels of digital signals in logic circuits whose supply voltage is below the nominal value for the corresponding technology (for example BiCMOS) become unreliable. Inter alia, this is because the signal levels which occur when the voltage supply is below normal are no longer adequate to correctly drive the gates of switching transistors in the logic circuit. The output signals then fluctuate unreliably between an H (High) and L (Low) level, or are at an undefined level between these two levels. Special measures are therefore required in order to produce well-defined H and L levels for the respective control signal even when the supply voltage is below normal. According to the prior art, circuit arrangements with pull-up or pull-down resistors are known for CMOS logic devices. FIG. 1 shows a circuit according to the prior art. The logic circuit LS is formed by an inverter which has an input E and an output A, having a PMOS transistor P and an NMOS transistor N, whose controllable paths are connected in series between the supply voltage VDD and ground GND, with the gate connections of the MOS transistors being connected to one another at the input E for an input signal Z1. The output A is coupled to a node K between the two controllable paths through the MOS transistors P, N. Furthermore, a pull-down resistor R is connected to the output A and draws a signal Z2, which is produced at the output, to ground GND when the voltage supply is below normal. Logic circuits LS and inverters such as these are generally used as output drivers by more general logic circuits. During normal operation, that is to say when the voltage supply is adequate, an input signal Z1 is inverted to form the output signal Z2, and is emitted at the output A. However, if the supply voltage VDD falls well below the nominal supply voltage (which is governed by the technology used, for example CMOS), the transistors P, N no longer operate reliably, and can no longer produce any currents. In this situation, the pull-down resistor R “wins” and draws the potential at the output A to the L level, or to ground GND. This zero or L level of the output control signal Z2′ is reliably maintained until the supply voltage VDD collapses completely. The circuit arrangement according to the prior art in FIG. 1 with a pull-down resistor has the major disadvantage that current is dissipated via the resistor R during normal operation as well if the PMOS transistor P is driven by the input signal Z1 in order to produce an H level as the output signal at the output A. The increased power consumption thus leads to rapid discharging of the battery and hence to the corresponding appliance having a short operating period. The European Patent Application EP 0 999 493 A2 describes a circuit arrangement for voltage monitoring and for production of a reset signal. The corresponding CMOS circuit requires a reference voltage source and a comparator circuit. The circuit is provided in an appliance which has circuits from different technologies, and is thus designed using that technology which can operate at the lowest possible supply voltage—in comparison to the other integrated circuits in the appliance. The use of the low-voltage circuit to produce the reset signals has the disadvantage that the logic gates using this very low-voltage technology also fail beyond a specific supply voltage level, and the reset signals then fluctuate as a function of parasitic leakage currents. A further disadvantage is that the respective low-voltage technology cannot be supplied directly from the battery or rechargeable battery supply voltage. Furthermore, the voltage threshold down to which a well-defined H level or L level can be emitted as a reset signal or locked signal is dependent on the power consumption of the comparator and of the reference voltage source. The object of the invention is thus to provide a circuit arrangement for monitoring a power supply and for reliable locking of signal levels when the supply voltage is below normal, which reliably produces a well-defined logic level down to extremely low residual supply voltages, saves power and can be integrated with little effort. The object is achieved by a circuit arrangement for monitoring a voltage supply and for reliable locking of a signal emitted from a logic circuit at a supply voltage level when an external supply voltage level decreases, having the features of Patent Claim 1. Advantageous refinements and developments of the invention can be found in the respective dependent claims. Accordingly, a circuit arrangement for monitoring an external voltage supply and for reliable locking of a signal, which is emitted from a logic circuit, at a voltage level of an internal voltage supply that is below normal, is provided which has a voltage divider which is connected between a first and a second external supply voltage and produces a potential level for a switching signal. The circuit arrangement according to the invention furthermore has a controllable switch which separates the internal voltage supply, which has a first and a second internal supply voltage, from the logic circuit in order to deactivate the latter as a function of a locking signal which is produced from the switching signal. In addition, a high-value resistor is provided, by means of which the signal which is emitted from the deactivated logic circuit is drawn to the level of one of the two internal supply voltages. The circuit arrangement according to the invention has the advantage that it sets the signal emitted from the logic circuit to one of the two internal supply voltage levels even when the supply voltages are very low, and in practice down to complete collapse of the external voltage supply, and hence of the internal voltage supply as well. The circuit arrangement thus produces a reliable signal which is logically referenced to one of the internal supply voltage levels and follows the respective decreasing internal supply voltage level. Since the resistor is designed to have a high resistance, virtually no additional power is consumed, in comparison to the prior art. The voltage divider in the circuit arrangement according to the invention is advantageously designed such that, when the logic circuit is processing an input signal which is referenced to the external supply voltages, the locking signal deactivates the logic circuit before the level or levels of the input signal received from the logic circuit becomes or become unacceptable in the event of a drop in the external supply voltages. This advantageously means that the circuit arrangement produces the locked signal before the input signal (which is referenced or referred to the external supply voltages) to the logic circuit fluctuates between the H level and the L level, and is thus no longer well-defined, owing to the external supply voltages being too low. According to one preferred embodiment of the circuit arrangement according to the invention, a monitoring circuit is provided, which has a first supply voltage connection for application of the first external supply voltage, a second supply voltage connection for application of the second external supply voltage, and at least one output for emission of the locking signal. In this case, at least two resistors are connected as a voltage divider between the supply voltage connections, and the locking signal is produced as a function of a voltage potential which can be tapped off between the resistors. The logic circuit has a first supply voltage connection and a second supply voltage connection, with the second internal supply voltage being applied to the second supply voltage connection, a control signal input for an input signal, and an output for the signal which is produced from the input signal by the logic circuit. The controllable switch is provided between the first internal supply voltage and the first supply voltage connection of the logic circuit, and connects the first internal supply voltage to the first supply voltage connection of the logic circuit as a function of the locking signal. The high-value resistor is provided between the output of the logic circuit and the second internal supply voltage. In one preferred embodiment, the internal and external first supply voltages and the internal and external second supply voltages are each at the same voltage level. In this case, the circuit arrangement according to the invention ensures reliable self-locking of the output signal when the supply voltage collapses. According to one preferred development of the circuit arrangement according to the invention, the monitoring circuit has a third supply voltage connection for application of the first internal supply voltage, and has a fourth supply voltage connection for application of the second internal supply voltage. Furthermore, the monitoring circuit has a third resistor, a first MOS transistor with a controllable path and a gate connection, and a second MOS transistor with a controllable path and a gate connection, wherein the third resistor and the two controllable paths are connected in series between the two internal supply voltages and the switching signal is coupled to the gate connection of the second MOS transistor. The monitoring circuit furthermore provides a complementary MOS transistor with a controllable path and a gate connection, and has a fourth resistor, wherein the controllable path through the complementary MOS transistor and the fourth resistor are connected in series between the two internal supply voltages. The gate connection of the complementary MOS transistor is connected to a potential node between the third resistor and the controllable path through the first MOS transistor, and the gate connection of the first MOS transistor is connected between the controllable path through the complementary MOS transistor and the fourth resistor. According to the preferred development, the monitoring circuit has a third MOS transistor with a controllable path and a gate connection, wherein the controllable path through the third MOS transistor is connected between the gate connection of the complementary MOS transistor and the second internal supply voltage. The switching signal is connected to the gate connection of the third MOS transistor. The monitoring circuit produces a first locking signal which can be tapped off at the gate connection of the complementary MOS transistor, and a second locking signal which can be tapped off at the gate connection of the first MOS transistor. The preferred development offers two locking signals, so that an output level from connected logic circuits is locked either at a level which is referenced to the first internal supply voltage or at a level which is referenced to the second internal supply voltage. According to a further advantageous development of the circuit arrangement according to the invention, the monitoring circuit furthermore has a first and a second MOS control transistor, which each have a controllable path and a gate connection. In this case, the controllable path through the first MOS control transistor is connected between the controllable path through the first and the second MOS transistor, and the controllable path through the second MOS transistor is connected between the gate connection of the complementary MOS transistor and the controllable path through the third MOS transistor. An external control signal is applied to the gate connections of the two MOS control transistors. This advantageous development furthermore provides locking at in each case one of the two internal supply voltage levels by means of the external control signal, even at the nominal external supply voltage. In one preferred embodiment of the circuit arrangement according to the invention, the controllable switch or switches has or have an MOS switching transistor with a controllable path and a gate connection, with the locking signal being connected to the gate connection of the respective MOS switching transistor. The controllable path through the MOS switching transistor is provided between one of the internal supply voltages and a supply voltage connection of the respective logic circuit. The logic circuit preferably has an inverter as the output driver. During normal operation, an inverter offers the advantage that the output level from the logic circuit is well-defined, and that the high-value resistor according to the invention can easily be connected to one output. The circuit arrangement according to the invention is preferably designed using a first MOS technology, and the control signals from the logic circuits drive circuits which are designed using a second technology. In this case, it is particularly advantageous for the first technology to operate at higher supply voltages than the second technology. In this case, the circuit arrangement according to the invention is provided in a domain which, for example, can be directly connected to the external or battery supply voltage and supplies reliable, possibly locked, control signals to circuits in a low supply voltage domain. Further advantageous refinements and a development of the invention are the subject matter of the dependent claims and of the description, with reference to the figures. The invention will be explained in more detail in the following text with reference to the exemplary embodiments and the schematic figures, in which: FIG. 1 shows a circuit with a pull-down resistor according to the prior art; FIG. 2 shows a circuit arrangement according to one preferred embodiment of the invention; FIG. 3 shows a block diagram of one embodiment of a functional block of the circuit arrangement according to the invention; FIG. 4 shows a block diagram of one application example of the invention; and FIG. 5 shows a circuit arrangement according to the invention, based on an advantageous development of the invention. Identical or functionally identical elements in the figures are provided with the same reference symbols. FIG. 1 has already been described in the introduction to the description. FIG. 2 shows a circuit arrangement according to a first preferred embodiment of the invention. The circuit arrangement 1 has a monitoring circuit 2 which has a first supply voltage connection 3 for application of the first external supply voltage VBAT1, a second supply voltage connection 4 for application of the second external supply voltage VBAT, two resistors 6, 7 which are connected in series between the supply voltage connections 3, 4, and an output 5 which is connected to a potential node 25 between the two resistors 6, 7. A voltage potential VLOCK is dropped at the potential node 25, and can be tapped off as a locking signal LOCKP at the output 5. The locking signal LOCKP is passed to a functional block 201, which has an inverter as the logic circuit 8 and a PMOS switching transistor 15 as the controllable switch 13, as well as a high-value resistor 14 which is connected to an output 12 of the logic circuit and to a second internal supply voltage VSS. The controllable path through the PMOS switching transistor 15 is connected between the first internal supply voltage VDD and a first supply voltage connection 9 of the logic circuit 8. The locking signal LOCKP is passed to the gate connection of the PMOS switching transistor 15. The logic circuit 8 or the inverter has a PMOS transistor 26 and an NMOS transistor 27, whose controllable paths are connected between the first supply voltage connection 9 of the logic circuit 8 and a second supply voltage connection 10, to which the second internal supply voltage VSS is applied. The gate connections of the PMOS transistor 26 and of the NMOS transistor 27 are connected to one another, and are jointly connected to the input 11 of the logic circuit 8. The input 11 is supplied with a control signal Z1 which is related to the external supply voltage level BAT1, BAT2. In this case, it is not essential for an H level to correspond to the first external supply voltage. It may also be proportional to the external supply voltage, or may be referenced to it by means of some other non-linear relationship. The inverted input signal can be tapped off as the output signal Z2 between the controllable paths of the MOS transistors 26, 27, and is passed to the output 12 of the inverter 8. By way of example, the following text is based on the assumption that a logic H level corresponds to the first external supply voltage VBAT1, and that a logic L level corresponds to the second external supply voltage VBAT2. Other references for the logic levels are, of course, also possible. When the external supply voltages VBAT1, VBAT2 are at the nominal values for the respective technology used for the design of the higher-level circuits, which are not considered here, and, in particular, provide the input signal Z1 for the logic circuit, the PMOS switching transistor 15 has a low impedance as a result of the locking signal LOCKP, and passes the first supply voltage VDD to the inverter 8. The resistors 6, 7 in the voltage divider have resistances such that the controllable switch 13 passes on the internal supply voltage VDD to the logic circuit 8 or the inverter during normal operation, that is to say with the nominal external supply voltage (which, in particular, supplies higher-level circuit parts which generally require higher voltages than VDD, VSS). If the external supply voltage VBAT1 decreases, for example in the event of a battery being discharged, the PMOS transistor 15 impedance becomes continuously high owning to the falling level VLOCK of the locking signal LOCKP. In the situation where, for example, the external and internal supply voltage levels are the same, VBAT1=VDD and VBAT2=VSS, the voltage between the source S of the MOS switching transistor 15 which faces the first supply voltage VDD and the gate G of the MOS switching transistor which is at the voltage potential which is dropped across the voltage divider 6, 7 falls when the supply voltage range decreases. In consequence, the MOS switching transistor 15 cuts off the logic circuit 8 when the voltage supply falls, and deactivates it. The following text is based on the assumption that VBAT1=VDD and VBAT2=VSS in this preferred embodiment. If the input signal Z1 to the logic circuit 8 indicates by means of an H level that there is a voltage drop in the supply voltage VDD, VSS, or that the circuit or appliance in which the circuit arrangement according to the invention is used has run down as a consequence of this, the output control signal Z2 from the inverter or from the logic circuit 8 is emitted as a reset signal RES at the L level. Before the supply voltage VDD, VSS becomes so low that the MOS transistors 26, 27 in the logic circuit 8 can no longer operate, the impedance of the controllable path through the MOS switching transistor 15 becomes high, and the logic circuit 8 is thus deactivated by interrupting the supply voltage. This is done because the gate connection of the MOS switching transistor 15 follows the supply voltage level VDD. When the logic circuit 8 has been deactivated, the output signal Z2 from the logic circuit 8 at the output 12 follows the second supply voltage level VSS, that is to say an L level, via the high-value resistor 14. Thus, when the supply voltages VDD, VSS and the supply voltage range VDD-VSS are far lower than the nominal value for the respective technology used for the design of the circuit arrangement, for example CMOS, this therefore ensures that the output control signal Z2 is locked at an L level as a reset signal RES. The locking at the L level takes place reliably virtually down to a negligibly small supply voltage range VDD-VSS. During normal operation, that is to say at the nominal supply voltages VDD, VSS, only an insignificantly greater amount of current is drawn in the circuit arrangement according to the invention, since the resistor 14 can be chosen to have a very high value. FIG. 3 shows a circuit arrangement of a functional block 202 which produces an output signal INT that is locked to the H level when a corresponding locking signal LOCKN is supplied at the L level. The functional block 202 carries out a complementary function to the functional block 201 shown in FIG. 2. The functional block 202 has an inverter 108 which is designed analogously to the inverter or the logic circuit 8 shown in FIG. 2. Furthermore, the functional block 202 has a controllable switch 113, which is coupled to a second supply voltage connection 109 of the inverter 108, and is coupled to the second internal supply voltage VSS, in this example ground/frame. The controllable switch has an NMOS transistor 115 whose controllable path is used as a switching path and is controlled by its gate connection, to which the second locking signal LOCKN is connected. The inverter has an input 111, an output 112, a first supply voltage connection 110 and a second supply voltage connection 109, with the controllable paths through a PMOS transistor 126 and an NMOS transistor 127 being connected between the supply voltage connections. The gate connections of the MOS transistors 126, 127 are coupled to the input of the inverter 108, and are thus controlled by an input control signal Z3. The output 112 of the inverter produces an output control signal Z4, which is passed to the first internal supply voltage VDD via a “weak”, that is to say high-value pull-up resistor 114. The functional block 202 operates in an analogous manner to that of the functional block 201, with the difference that the second locking signal LOCKN at the H level allows a normal inverter method of operation, while it deactivates the inverter or the logic circuit 108 when at the L level, so that an output signal INT is produced which is drawn via the high-value resistor 115 to the H level, which is referenced to the first internal supply voltage. FIG. 4 shows a block diagram of one application example for a circuit arrangement according to the invention. An advantageous development of the circuit arrangement 101 according to the invention (see FIG. 5) is accordingly provided in a power supply management unit 302, for example for a mobile telephone. The power supply management unit 302 may be designed, for example, using 5-volt BiCMOS technology and has the supply voltage connection 304 for connection of an external battery 305, which produces a first external supply voltage VBAT1. The second external supply voltage VBAT2 is connected to ground/frame GND from this point here. The power supply management unit 302 has a battery voltage monitoring unit 306 which monitors the state of charge and the presence of the battery and emits a control signal LC which indicates whether the voltage VBAT1 being produced by the battery 305 corresponds to the nominal values for the BiCMOS circuits. The power supply management unit 302 has a voltage control unit 307 for the voltage supply for a real time clock 301 in a system control unit 300. In this case, the real time clock 301 in the system control unit 300 is designed using low-voltage technology, for example 1.8-volt CMOS technology. A corresponding internal supply voltage VDD is provided by the voltage control unit 307 from the battery voltage VBAT1. The system control unit 300 is supplied from the power supply management unit 302 with the nominal internal supply voltage VDD of about 1.8 volts, with a large buffer capacitor 308 being coupled to the power supply line 309, which connects the power supply management unit 302 and the system control unit 300 to one another and also supplies the voltage VDD to the functional blocks 102, 201, 202 of the circuit arrangement according to the invention. The buffer capacitor 308 ensures a temporary but decreasing supply voltage VDD to the real time clock 301 and to the circuit arrangement 101 even after removal of the battery 305, according to the advantageous development of the invention. The circuit arrangement 101 according to the invention has functional blocks 102, 201, 202, with the functional blocks 201 and 202 corresponding to those in FIGS. 2, 3, while the block 102 will be described in more detail in the following FIG. 5. The circuit arrangement 101 according to the invention has an input 103 for the control signal LC, which indicates whether the nominal power supply is being ensured by the battery. When the connected battery 305 is operating, the signal is at the H level, which corresponds to the battery voltage VBAT1. If the battery has been discharged or disconnected, the battery voltage monitoring unit 306 sets the control signal LC to the L level, that is to say to ground. The circuit arrangement 101 according to the advantageous development of the invention emits a first control signal RES as a reset signal to the real time clock in the system controller 300, as well as an interrupt control signal INT, which is likewise passed to the real time clock 301. If the battery 305 is disconnected from the power supply management unit 302, the battery voltage monitoring unit 306 sends a control signal LC to the circuit arrangement according to the invention, which then sends a reset signal RES at the L level as well as an interrupt signal INT at the H level to the real time clock, thus signalling to the latter that it should continue to carry out its function. Since the battery 305 is no longer producing any voltage or has been disconnected, the external supply voltage VBAT1 thus falls not only as the reference value for the control signals LC, Z1, Z2 but also as the nominal internal supply voltage for the circuit arrangement 101 according to the invention and for the real time clock 301. Since, however, the real time clock 301 is designed for use in a very low-voltage domain, in this case using 1.8-volt CMOS technology, it can initially continue to operate. However, a reset signal RES and an interrupt signal INT at the appropriate levels must reliably be supplied to it. The respective, locked control signals RES, INT are produced by the circuit arrangement 101 according to the invention. FIG. 5 shows a circuit arrangement 102 according to the invention, based on the advantageous development as used in the exemplary embodiment shown in FIG. 3. The block 102 as illustrated in FIG. 4 has an input 103 for the external control signal LC that is supplied from the power supply management unit 302, a first supply voltage connection 3 for application of the external battery voltage VBAT1, and a second supply voltage connection 4, which is in this case connected to ground GND. A third first supply voltage connection 31 is provided for the controlled supply voltage VDD, which controlled supply voltage VDD is supplied from the voltage control unit 307, and a fourth supply voltage connection 41, which is in this case connected to ground/frame GND. The functional block 102 also has an output 5 for emitting a first locking signal LOCKP, and an output 15 for emitting a second locking signal LOCKN. Two resistors 6, 7 are connected as a voltage divider between the first external supply voltage VDD, the voltage VBAT1 produced by the battery 305 and ground GND or the second supply voltage connection 4, in which case a voltage potential VLOCK can be tapped off at a potential node 125 between the two resistors 6, 7. A third resistor 16, a first MOS transistor 17 with a controllable path and a gate connection, a first control transistor 23 with a controllable path and a gate connection, and a second MOS transistor 18 with a controllable path and a gate connection are provided, with the resistor 16 and the controllable paths through the first and second MOS transistors and the control transistor 23 being connected in series between the internal supply voltage VDD and ground GND. The external control signal LC is passed to the gate connection of the first control transistor 23, and the voltage potential VLOCK at the potential node 125 is passed to the gate connection of the second MOS transistor 18. Furthermore, a complementary MOS transistor 19 with a controllable path and a gate connection is provided, as well as a fourth resistor 20, with the controllable path through the complementary MOS transistor 19 and the fourth resistor 20 being connected in series between the two supply voltage connections 31, 41 for the respective internal supply voltages VDD, VSS/GND. The gate connection of the complementary MOS transistor 19 is connected to a potential node 21 between the third resistor 16 and the controllable path through the first MOS transistor 17. The gate connection of the first MOS transistor 17 is connected to a potential node 126 between the controllable path through the complementary MOS transistor 19 and the fourth resistor 20. A second MOS control transistor 24 with a controllable path and a gate connection, and a third MOS transistor 22 with a controllable path and a gate connection, are provided, with the controllable paths through the second MOS control transistor 24 and through the third MOS transistor 22 being connected in series between the gate connection of the complementary MOS transistor 19 and the second supply voltage connection 41 for the second internal supply voltage VSS or ground GND. The gate connection of the second MOS control transistor 24 is supplied with the external control signal LC. The gate connection of the third MOS transistor 22 is connected to the potential node between the two resistors 6, 7. The first locking signal LOCKP can be tapped off at the gate connection of the complementary MOS transistor 19, and the second locking signal LOCKN can be tapped off at the gate connection of the first MOS transistor 19. The first locking signal LOCKP is passed as a locking signal to a functional block 201 as is described in FIG. 2. The second locking signal LOCKN is passed to the functional block 202, which is described in FIG. 3. During normal operation of the advantageous development 101 and in the application example as is illustrated in FIG. 4, the external control signal LC is at the H level, thus indicating that a nominal voltage supply is ensured. During this normal operation, the control transistors 23, 24 are switched on. The resistors 6, 7 have values such that, when the supply voltage is nominal, an H level is in practice dropped at the potential node 125, so that the switching signal likewise switches on the second MOS transistor 18 and the third MOS transistor 22. The gate connection of the complementary MOS transistor 19 is then at the L level, and the first locking signal LOCKP is thus also at the L level. During this normal operation, the gate connection of the first MOS transistor 17 is then at the H level, so that the second locking signal LOCKN is also at the H level. Although the components in the functional block 102, 201, 202 are designed for nominal voltages around 2 volts, the control signals LC, Z1, Z3 are referenced to the 5-volt battery voltage. This does not damage the components. When the first locking signal is at the L level, a controllable switch 13 which is controlled by the first locking signal LOCKP and is shown in FIG. 2 does not deactivate the corresponding logic circuit. When the second locking signal LOCKN is at the H level, a controllable switch according to the invention and as is shown in FIG. 3 below likewise once again does not deactivate the connected logic circuit. During normal operation, the circuit arrangement 102 or 101 according to the invention does not influence the logic circuits. In a second mode of the circuit arrangement 102 according to the invention, the locking signals LOCKP, LOCKN are changed to the blocking or locking state by the external control signal LC. This means that the first locking signal LOCKP is at the H level, while the second locking signal LOCKN is at the L level. The controllable switches 13, 113 which are driven by the locking signals LOCKP, LOCKN thus deactivate the respective logic circuits 8, 108 connected to them. The functional blocks 201, 202 therefore produce output signals RES, INT which are locked to the first supply voltage (in the case of the first locking signal LOCKP and the functional block 201 from FIG. 2) or to the second supply voltage VSS or to ground in the case of the application example shown in FIG. 4 (in the case of the second locking signal LOCKN and the functional block 202 from FIG. 3). Thus if, in the second operating mode, the external control signal LC is at the logic L level, the two MOS control transistors 23, 24 provide isolation. The current flow through the third resistor 16 is then interrupted, and the gate connection of the complementary MOS transistor 19 is drawn to the H potential. The first locking signal LOCKP is then also at the H level. The current flow through the fourth resistor 20 is then interrupted and the fourth resistor 20 draws the gate connection of the first MOS transistor 17 to the L level. The second locking signal LOCKN is then also at the L level. However, the signals LC, Z1, Z3 are produced in a circuit which is designed using a technology which requires the battery voltage VBAT1 for reliable operation. In this example, this is the battery voltage monitoring unit 306. If the battery voltage VBAT1 falls sharply, then the battery voltage monitoring unit 306 can no longer ensure that the levels of the control signals LC, Z1, Z3 are well-defined. For example, if the battery voltage VBAT1 is low, the signal LC which indicates the battery state can oscillate at levels around 2 volts owing to poorly operating logic circuits in the battery voltage monitoring unit 306, thus incorrectly indicating normal operation to the functional block 102. The circuit arrangement 101 according to the invention prevents this. In a third operating state, the external supply voltage VBAT2 falls well below the corresponding nominal supply voltage. The circuit arrangement according to the invention must now change the output signals from the connected logic circuits 8, 108 to the respective safe level, which, as a reset or interrupt signal RES, INT, indicates to the real time clock 301 that it should continue to operate as a rudimentary function. This is indicated by a reset signal RES at the L level and by an interrupt signal INT at the H level. However, this H level is referenced to the internal supply voltage or to the residual voltage produced by the buffer capacitor 308. If the external supply voltage VBAT1 is no longer sufficient to produce an external control signal LC referenced to it because the corresponding logic gates are designed for a higher nominal supply voltage and have so-called floating gates, the voltage divider 6, 7 ensures that the second and third MOS transistors 18, 24 have a high impedance. Then, as in the second operating state described above, the third resistor 16 draws the gate of the complementary MOS transistor 19 and the first locking signal LOCKP to the H level, and the further resistor 20 draws the gate connection of the first MOS transistor 17 and the second locking signal LOCKN to the L level. In this situation, that is to say when the external supply voltage VBAT1 is falling, the use of the two resistors 6, 7 in the voltage divider can be seen as being particularly advantageous because, theoretically, the resistors can operate down to a supply voltage range of 0 volts. The locking signals LOCKP, LOCKN which are produced according to the invention thus control the controllable switches 13 as illustrated in FIG. 2, and 113 as illustrated in FIG. 5. The circuit arrangement according to the invention thus ensures, when the supply voltage is unreliable or too low so that the logic levels of control signals such as the external control signal LC or the input signals Z1, Z3 to the logic circuits 8, 108 fluctuate or assume intermediate level values, that well-defined control signals are produced, which are locked and are referenced to the internal supply voltages (which may likewise be falling). Owing to the use of high-value resistors, which draw the corresponding levels to one of the internal supply voltages when locking occurs, the voltage arrangement according to the invention has very low losses. Since PMOS or NMOS transistors are provided as the controllable switches, whose gate connections are controlled by the potential on a resistive voltage divider, operation of the circuit arrangement is possible virtually to the point where a supply voltage collapses. Although the present invention has been described above with reference to a preferred application example and with reference to preferred embodiments, it is not restricted to them but can be modified in many ways. The invention is not restricted to use in mobile radio applications or to designs using CMOS and BiCMOS technologies. In fact, the circuit arrangement according to the invention can be used whenever signal levels which have become uncertain or unreliable as a result of a voltage drop must be locked at predefined safe reference levels. | 20050124 | 20080219 | 20050804 | 64530.0 | 0 | NGUYEN, MATTHEW VAN | CIRCUIT ARRANGEMENT FOR MONITORING A VOLTAGE SUPPLY, AND FOR RELIABLE LOCKING OF SIGNAL LEVELS WHEN THE VOLTAGE SUPPLY IS BELOW NORMAL | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,330 | ACCEPTED | Door closer hold-open apparatus | The present invention relates to a hold-open apparatus for controlling the position of a door, preferably a screen door or storm door. The apparatus is used in conjunction with a piston assembly and can maintain a door in a predetermined open position, such as about 45° to about 100° in relation to a closed position. In a preferred embodiment, the apparatus can automatically lock and/or unlock when the door reaches predetermined positions. The apparatus advantageously can be retrofitted to existing door assemblies. | 1-13. (canceled) 14. A device for controlling the position of a door relative to a door frame, wherein the door has one end of a cylinder closing mechanism operatively attached thereto and where another end of the cylinder closing mechanism is attached to a door frame through a bracket, said device comprising: (a) a hold-open apparatus having a first end, a second end, and an interconnecting central portion, wherein said apparatus second end is adapted to engage an end of a cylinder of the cylinder closing mechanism when the door has been opened to at least a predetermined degree to maintain the door in an open position; and (b) an adapter having a male portion which operatively connects said cylinder closing mechanism end to the bracket, and a female portion, wherein said apparatus first end is operatively connected to said adapter female portion; or (c) a spring is connected to said apparatus first end which biases the apparatus towards the cylinder closing mechanism, wherein the spring will cause the apparatus second end to automatically engage said cylinder end when the predetermined angle has been reached. 15. A device according to claim 14, wherein said spring is utilized and wherein said apparatus first end is operatively connected to the bracket in an aperture separate from an aperture which connects the cylinder closing mechanism to the door frame. 16. A device according to claim 14, wherein said adapter is utilized, and wherein the male portion operatively connects an end portion of a rod of the cylinder closing mechanism to the bracket. 17. A device according to claim 15, wherein the apparatus second end moves in a horizontal plane and in a radial arc with respect to the apparatus first end, and wherein said second end is engageable with a side of said cylinder end. 18. A device according to claim 16, wherein the apparatus second end moves in a horizontal plane and in a radial arc with respect to the apparatus first end, and wherein said second end is engageable with a side of said cylinder end. 19. A device according to claim 17, wherein said apparatus central portion is length adjustable, or wherein said bracket has elongated apertures, or a combination thereof. 20. A device according to claim 18, wherein said apparatus central portion is length adjustable, or wherein said bracket has elongated apertures, or a combination thereof. 21. A device for controlling the position of a door relative to a door frame to which the door is operatively connected, comprising: a cyclinder closing mechanism adapted to have an end portion operatively connected to the door; a bracket having a first end portion adapted to be connected to the door frame and a second end portion operatively connected to the cylinder closing mechanism; an adapter having a pin element and a hold-open apparatus connecting portion, the pin element operatively connected in an aperture of the bracket; and a hold-open apparatus having a first end, a second end, and an interconnecting central portion, wherein the apparatus first end is operatively connected to the adapter hold-open apparatus connecting portion, and wherein the apparatus second end is adapted to engage an end of a cylinder of the cylinder closing mechanism when the door has been opened at least a predetermined degree to maintain the door in an open position. 22. The device according to claim 21, wherein the adapter pin element operatively connects an end portion of a rod of the cylinder closing mechanism to the bracket. 23. The device according to claim 22, wherein the adapter hold-open apparatus connecting portion has the shape of a cylinder having an aperture, and wherein the second end of the hold-open apparatus is operatively connected in the aperture. 24. The device according to claim 23, wherein the adapter aperature is angled about 10 to about 45 degrees with respect to vertical to allow the apparatus to be locked in place automatically when the door is opened to the predetermined degree. 25. The device according to claim 21, wherein a spring is operatively connected to the adapter to bias the hold-open apparatus second end towards the cylinder closing mechanism. 26. The device according to claim 24, wherein the hold-open apparatus second end is located between the door and the cylinder closing mechanism, and wherein the predetermined degrees the door has been opened is from about 45° to about 100°. 27. The device according to claim 24, wherein an upper end of the adapter aperture is located at a position of about 80° to about 120° with respect to a horizontal plane wherein a line normal to a vertical plane of the door frame to a center of the bracket aperture represents a zero degree position. 28. The device according to claim 21, wherein the hold-open apparatus second end moves in a horizontal plane and in a portion of a radial arc with respect to the apparatus first end and such movement can be independent of cylinder movement, and wherein said second end is engageable with a side of said cylinder end. 29. The device according to claim 27, wherein the upper end of the apparatus bracket aperture is located at a position of about 85 to about 95 degrees with respect to the horizontal plane. 30. The device according to claim 21, wherein said apparatus central portion is length adjustable, or wherein said bracket has elongated apertures, or a combination thereof. 31. The device according to claim 23, wherein said apparatus central portion is length adjustable, or wherein said bracket has elongated apertures, or a combination thereof. 32. The device according to claim 16, wherein the adapter female portion has the shape of a cylinder having an aperture and the second end of the hold-open apparatus is operatively connected in the aperture. 33. The device according to claim 32, wherein the adapter aperature is angled about 10 to about 45 degrees with respect to vertical to allow the apparatus to be locked in place automatically when the door is opened to the predetermined degree. | FIELD OF THE INVENTION The present invention relates to a hold-open apparatus for controlling the position of a door, preferably a screen door or storm door. The apparatus is used in conjunction with a piston assembly and can maintain a door in a predetermined open position, such as about 45° to about 100° in relation to a closed position. In a preferred embodiment, the apparatus can automatically lock and/or unlock when the door reaches predetermined positions. The apparatus advantageously can be retrofitted to existing door assemblies. BACKGROUND OF THE INVENTION Screen doors, storm doors and the like, are utilized on millions of homes to provide fresh air, weather protection, and security, etc. The door typically includes a means for closing the door such as a spring or piston assembly or the like. A popular means for controlling the door position utilizes a piston assembly which typically includes a cylindrical tube attached at one end to a bracket connector on the door. The inner surface of the cylindrical tube generally includes a spring loaded piston attached to a reciprocating connecting rod which extends from the piston and out of the tube. The end of the connecting rod opposite to the end carried and connected within the cylindrical tube typically is attached to a bracket which is connected to the door frame. When the door is opened, the connecting rod is pulled from the cylindrical tube, causing the piston to travel within the inner surface of the cylinder and thereby compress a spring coiled between an inner wall of the cylinder and the piston. When the door is released, energy stored within the spring pushes against the surface of the piston, causing it to slide within the cylinder and the connecting rod is drawn back within the cylindrical tube thereby closing the door. The retracting momentum of the piston is typically cushioned by compression of fluid such as air or oil inside the cylinder tube to create a damping resistance opposite the force that propels the door to close for better control of the speed and force at which the door closes. Many different devices have been invented in order to maintain the door in a certain position, i.e., partially or completely open. One such device is a hold-open washer which has an aperture through which the connecting rod extends. The hold-open rod must be manually set once the door is opened at a position along the connecting rod. After the door is released, the connecting rod begins to be drawn back within the cylinder and is stopped when the hold-open washer makes contact with the end of the cylinder, binding the hold-open washer against the piston rod. The door will remain held in place until the door is opened and the hold-open washer is manually repositioned transversely along the connecting piston rod and away from the cylindrical tube. U.S. Pat. No. 3,708,825 relates to a door check and door stop combination. The door check is made up of a pneumatic cylinder and piston which control the rate at which the door closes to prevent the door from slamming. A stop is attached to the distal end of the piston rod and lies along the side of the cylinder. The stop is made of a sheet material and has an aperture through it which receives the cylinder. The stop has a handle which may be engaged by the user's hand to move the stop from position in engagement with the cylinder. U.S. Pat. No. 4,639,969 relates to door closer mechanism for attachment to, or incorporation into, a standard spring type door closer, or for use with a standard spring type door closer. A reversible pawl and ratchet assembly operating on a rod between the door and door casing allows the door to ratchet open where it is held by the pawl until a slight closing pull or push on the door reverses action of the pawl and allows the door to close. While the door is closing or is fully closed, reopening of the door resets the pawl for again holding the door open as desired. U.S. Pat. No. 4,815,163 relates to a storm door lock apparatus set forth wherein a clamp is secured to an associated screen-door type closure member that further secures a slidable rod mounted with an abutment surface for actuation by a user with a pivoted lever at the other end of said rod for canting about a piston rod associated with a door closure. Additionally, a generally “L” shaped link is securable to the abutment member for allowing engagement and access by a user. U.S. Pat. No. 5,575,513 relates to a receptacle for propping the cylinder of a cylinder-and-plunger strut in extended position of the strut includes two side-by-side cylindrical chambers, one being of a size to embrace the jack plunger rod but not the jack cylinder and the other chamber being of a size to slide over the jack cylinder, which chambers are interconnected by a slot sufficiently narrower than the jack plunger rod to enable the receptacle to move into a position embracing the jack plunger rod by snap action, and the larger chamber being of a size to slide lengthwise over the cylinder and having in it a lengthwise slot sufficiently narrow so as not to be able to pass the cylinder through it but sufficiently wide to pass the plunger rod through it. U.S. Pat. No. 5,592,780 relates to an apparatus for controlling the position of a door suitable for use in association with door closing piston assemblies having a spring-biased reciprocable door closing piston rod and a latch plate transversely slidable along the length of the piston rod. U.S. Pat. No. 5,659,925 relates to a holding mechanism attached to a generic door closing cylinder. There are various disadvantages inherent in all of the prior art devices. To the Applicant's knowledge, none can be automatically locked open and released by simply moving the door without manual intervention. The prior art devices are often rather clumsy to manipulate when attempting to set or release a latch. Other disadvantages of the prior art devices are that they are rather complicated, hard to maintain, and expensive to produce. SUMMARY OF THE INVENTION The present invention discloses and describes a device including a hold-open apparatus which can be used in combination with a screen or storm door piston assembly. Piston assemblies are commonly utilized in the industry to maintain or bias a door in a closed position. The hold-open apparatus is operatively connected at one end to the piston assembly, preferably a bracket thereof which is connected to a door casing or jamb. When the door is opened to a predetermined angle with respect to the door frame, a second end of the apparatus can be engaged with a cylinder end of the piston assembly and hold or maintain the door in an open position. Preferably the hold-open apparatus automatically engages and disengages the cylinder, unlike the prior art devices. The hold-open apparatus is of a durable and reliable construction and can be easily and efficiently manufactured. Importantly, the apparatus can be retrofitted to an existing storm or screen door with minimal effort. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and other features and advantages will become apparent by reading the detailed description of the invention, taken together with the drawings, wherein: FIG. 1 is a perspective view of one embodiment of a hold-open apparatus of the present invention. FIG. 2 is a top view of the structure shown in FIG. 1. FIGS. 3A-3B illustrate end views in section of various angular positions for the apparatus bracket aperture. FIG. 4 is a top view of the hold-open apparatus in a locked position. FIG. 5 is an embodiment of a hold-open apparatus having an adjustable length. FIG. 6 illustrates a partial side view of a further embodiment of a hold-open apparatus. FIG. 7 illustrates a partial perspective view of a further embodiment of a hold-open apparatus. DETAILED DESCRIPTION OF THE INVENTION Making reference now to the drawings wherein like numerals indicate like or corresponding parts throughout the several figures, a new and improved door closer hold-open apparatus will be described. Numerous households utilize a storm, screen or a like door to moderate or protect the interior of a house from heat, cold air, insects, etc. As illustrated in FIG. 1, typically a door 10 is biased in a closed position utilizing a door closer assembly 20. The door closer 20 generally comprises a pneumatic spring or hydraulic type dampener cylinder 22 which is connected at a head end to the door 10 by a bracket 26 through a pin 27 or other securing means. One end of reciprocating piston rod 24 is operatively connected to the cylinder 22. Attached to door casing, jamb or frame 12 at the side where the door 10 is hinged is a frame bracket 32. The frame bracket includes a means for connecting to second end of rod 24 such as bracket aperture 29. Normally an end portion of rod 24 will include an aperture which will allow pin 28 to connect rod 24 and bracket 32. The frame bracket 32 preferably includes mounting apertures 31 which are elongated to accommodate existing apertures in a door casing to allow for easy connection to door frame 12. Upon opening the door 10, piston rod 24 which is attached to door frame 12 by bracket 32, is pulled out from within the cylinder 22. When the door is then subsequently released, the cylinder pulls against rod 24, causing the rod to be drawn back within the cylinder 22 and the door 10 is thus swung closed. The prior art door closers include a manual locking tab or washer 25 which extends around rod 24 and is moveable thereon. The tab 25 is manually set when the door 10 is opened at a position along the rod 24 that will enable the door 10 to remain open by the blocking action of the tab. The tab 25 must be again manually moved when the door 10 is to be closed. In a preferred embodiment shown in FIG. 1, the hold-open apparatus 30 of the present invention is operatively connected at one end to the frame bracket 32, specifically through mounting aperture 33. The hold-open apparatus 30 can be formed from a rod or bar having a first end portion 34, a second end portion 35 and a central portion 36 interconnecting the ends 34, 35. As shown in FIG. 2, the hold-open apparatus frame bracket mounting aperture 33, is separate from the piston rod bracket aperture 29 to isolate the closing cylinder force from hold-open apparatus in order to permit free radial movement of the hold-open rod. The hold-open apparatus mounting aperture 33 is generally located to the inside of the piston rod bracket aperture 29, closer to the door frame 12. The hold-open apparatus frame bracket mounting aperture 33 is preferably located on bracket 32 a predetermined distance away from the door frame 12 which is greater or equal to the width or thickness of the door so that the apparatus has sufficient clearance and will not bind against the door 10 when in an open position. FIG. 2 illustrates one such preferred mounting position. Modern doors are generally about 1.5 inches thick. Earlier models are generally thinner. Therefore, it is preferred that the mounting aperture 33 edge be about 1, desirably from about 1.5, or preferably from about 1.75 inches from casing 12. Mounting aperture 33 diameter should be slightly larger than rod diameter, which preferably should be about 0.20 or about 0.25 inch or greater. One important feature of the invention is that the hold-open apparatus frame bracket mounting aperture 33 is present on the bracket 32 having distinct angular characteristics with respect to a vertical axis or the position of the mounting bracket to produce different modes of operation. The hold-open apparatus 30 embodiments alternatively work in four distinct modes of operation, i.e., (1) lock manually and unlock manually, (2) lock manually and unlock automatically, (3) lock automatically and unlock manually, and (4) lock automatically and unlock automatically. In one embodiment, the mounting aperture 33 is located so the central axis 38 is in a vertical position as shown in FIG. 3A, i.e., straight up and down, or as in further embodiments, the aperture is located incorporating a “tilt” angle of generally about 10 to about 45 degrees, desirably from about 20 to about 40 degrees, and preferably about 30 degrees, with respect to the vertical plane in a predetermined direction as shown in FIG. 3B (about 30 degrees tilt). To be able to lock and release the door automatically, a preferred embodiment, the above-noted “tilt” angle of vertical axis 38 places the upper portion or end of the aperture 33 at a predetermined position on the bracket with respect to the surrounding structure which is discussed hereinbelow. The position of the top edge of the bracket aperture 33 is measured in relation to a horizontal plane which runs midway through the aperture 33. A zero degree position is a line normal to the plane formed by the door casing 12 to the center of aperture 33 as shown in FIG. 2. A 270 degree position is a line normal to the plane formed by the door 10 in a closed position to the center of aperture 33 as shown in FIG. 2. Accordingly, the vertical tilt angle places the upper or top edge of aperture 33 at a position generally from about 80 degrees to about 120 degrees, desirably from about 85 to about 110 degrees, and preferably about 88 degrees to about 95 degrees, and most preferred about 90 degrees, with respect to the described horizontal plane. In this manner, gravity is used to lock and unlock the hold-open apparatus since the hold-open apparatus 30 is biased or tilted towards the cylinder 22 and rod 24 due to the position of the mounting aperture, and automatically locks in place when the door is opened to a predetermined angle. To automatically unlock the hold-open apparatus, the door is further opened, a predetermined angle, e.g., about 5 or about 10 degrees or more past the locked open position of the door. For example, if the door is locked open by apparatus at an angle of 80 degrees, the apparatus will unlock when the door is further opened to about 85 degrees. To maintain the hold-open apparatus central portion 36 in a relative horizontal position (see FIG. 1) as the door opens and closes, the angle between the first end 34 and the central portion 36 of the hold-open apparatus is-varied and is dependent on the tilt angle utilized if any. The hold-open apparatus 30 comprises a durable material, preferably a non-corrosive material such as stainless steel, core metal with nickel- alloy plating, metal reinforced plastic, or plastic either thermoplastic or thermoset. The apparatus is preferably formed from a rod, tube, or other similar construction. Generally any metal can be used, so long as the choice is strong and durable, with stainless steel being preferred. The hold-open apparatus 30 includes first end portion 34 which fits in mounting aperture 33 and is allowed to move therein. The first end 34 has a collar 34a (FIG. 1) or portion of greater diameter than aperture 33 to maintain the hold-open apparatus 30 at a certain height to provide clearance therefore. The central portion 36 and thus the length of the hold-open apparatus 30 extends generally about 4 to about 10 inches, desirably from about 6¾ to about 7¼, and preferably about 7 inches when measured from end to end. The length of central portion 36 is generally determined based on what angle the door is to be maintained in an open position as illustrated in FIG. 4. Generally, the longer the hold-open apparatus central portion 36, the greater angle the door will be positioned when latched open thereby. It is preferred that the hold-open apparatus 30 latches door 10 in an open position at an angle of about 45 degrees (as shown in FIG. 4) to about 100 degrees, desirably from about 70 degrees to about 95 degrees, and preferably from about 80 degrees to about 90 degrees with respect to a closed position as shown in FIG. 1. The hold-open apparatus 30 can also be designed so as to be variable in length as known in the art to accommodate the user's choice of operation and angle of the door open position, etc. Preferably the central portion of the hold-open apparatus length may be varied by utilizing two threaded ends 40, 41, a threaded collar 42 and at least one locking element or nut 43, 44 as shown in FIG. 5. To better understand the operation of the hold-open apparatus, it is important to note that the second or cylinder abutting end 35 of the hold-open apparatus 30 moves primarily in a horizontal plane and also in a radial arc with respect to the first end of the hold-open apparatus. In use, the first end 34 is located at the center of a circle and the second end 35 moves around a portion of the radial edge of the circle. It is also important to note that the second end 35 of the apparatus will engage in a hold-open position on the end of the closing cylinder that is closest to the door, i.e., between the cylinder and the door as illustrated in FIG. 4. There are numerous methods which can be utilized to hold a door in an open position using the hold-open apparatus. In one embodiment, first end 34 of the hold-open apparatus 30 will be substantially perpendicular to the jam bracket with the mounting aperture 33 present in the bracket 32 located so the central axis 38 is in a substantially vertical position as shown in FIG. 3A. With this embodiment, the hold-open apparatus must manually be engaged where the second end 35 is inserted against cylinder end as shown in FIG. 4, in hold-open position, but it will automatically disengage when the door is opened beyond a predetermined angle such as about 85 degrees. Automatic locking and unlocking action can be obtained by using a spring mechanism as explained hereinbelow if desired. In the manual locking embodiment, as the door is first opened, the cylinder exterior wall guides the second end of the hold-open apparatus so the second end swings with a similar angular motion as the door until the end of the cylinder 22 is extended past the second end of the hold-open apparatus. Then, the cylinder 22 no longer applies force to the hold-open apparatus. The hold-open apparatus 30 is then locked or tapped in place manually when the cylinder end is extended past the second end 35 of the hold-open apparatus 30. When the door is then opened wider than the hold-open position, the piston rod 24 forces the hold-open apparatus towards the door and in doing so disengages the hold-open apparatus 30. To close the door, no additional force need be applied to the hold-open apparatus as the second end of the hold-open apparatus will remain stationary as the door is opened beyond the locked position and will not move to a locked open position. As the door is released, the door will close with no interference from the hold-open apparatus 30. In further embodiments of the invention, an additional force such as from a spring, magnet or gravitation force is applied to the hold-open apparatus in order to automatically lock the door in an open position. In one embodiment, the mounting aperture 33 present in the bracket 32 is angled as described hereinabove, and gravitational force will be applied to the hold-open apparatus to provide for automatic locking of door 10 in an open position as shown in FIG. 4. In a further embodiment, the hold-open apparatus 30 includes a male/female pin adapter 50 as shown in FIG. 6. Pin 50 is designed having a portion 54 or element thereof which can fit within the existing aperture 29 utilized to secure piston arm 24 to bracket 32 while allowing free operation of the hold-open apparatus 30. Pin 50 has a male element or fitting 54 which is inserted into aperture 29 to secure piston arm 24 of the door closer 20 in typical fashion as shown. The hold-open apparatus 30 first end portion 34 is inserted into female connection 52 and is allowed to freely pivot therein in order to latch the door 10 in positions as described herein. If the male/female pin 50 is allowed to rotate as the door is opened and closed, no automatic action will occur, but, it is much easier to manually use as compared to the washer 25 that is commonly included with the piston assembly. When the male/female pin 50 is held fixed with, for example, a spring clip in a further embodiment, it will produce automatic locking/unlocking as explained herein. In one embodiment, the female aperture 53 present in the male/female pin is formed with an angle the same as described above for bracket aperture 33. The male/female pin 50 will provide automatic gravitationally induced locking and unlocking. In yet another embodiment, a magnet 80 can be attached to cylinder 22 at a butt end thereof as shown in FIG. 1. As the door is opened and the end of the cylinder is extended past the second end 35 of the hold-open apparatus 30, the magnet will cause the second end of the hold-open apparatus to move towards the piston rod and will engage in a locked hold-open position. When the door is opened further, the second end of the hold-open apparatus breaks away from the magnetic force and permits an automatic disengagement allowing the door to close freely. In yet another embodiment as shown in FIG. 7, the hold-open apparatus 60 includes a fixed coil spring 72 which is carried at the first end 64 thereof and maintained by a cotter pin 74 or other fastener means. The apparatus also includes a stop means comprising a lever or protrusion element 68 attached to the central portion 66 or end portion 64 of apparatus 60 and a binding post or stop 70 present on the bracket 32 produce automatic operation. The coil spring maintains a torque on the hold-open apparatus so the second end is always biased to move towards the piston 20 and will cause the second end of the hold-open apparatus 60 to lock open automatically when the door is opened to the desired position. When the door is further opened to a predetermined angle as noted hereinabove, and then released, the protrusion element will temporarily bind against post 70 and will permit the door to close freely. Many varieties of springs and resistance binding methods could be used. For example, the binding point could be present between the collar on the first end of the hold-open apparatus and the bracket and would work much like that of a bicycle kick stand. Another method could incorporate parallel leaf springs that would operate on a non-concentric area of the first end of the hold-open apparatus. This method would provide a positive snap action as the hold-open apparatus locks open and also disengages. Accordingly, the hold-open apparatus of the present invention can advantageously be utilized as an add-on accessory for a door closer mechanism which is already in use with little or no retrofitting necessary and without the need for installation tools. Alternatively, the hold-open apparatus can be included on newly constructed door closer mechanisms fitted to screen and storm doors. The present invention provides a simple method for maintaining a door in a latched position, whether operated manually, or automatically. The apparatus can be utilized by persons who have disabilities and cannot easily manipulate hands, fingers, digits, and/or bend over easily. Further, since the door can be activated to a hold-open position by simply opening the door, accidents that are caused by the closing door catching on the back of the legs or feet are minimized. The main advantage in all cases to the user and as compared to other similar devices is that the apparatus can be operated completely automatically by simply opening and closing the door without any additional manual operation. This feature is particularly advantageous when the user has both hands full when entering, or when assisting others since the door can be automatically locked open and disengaged by simply moving the door. In accordance with the patent statutes, the best mode and preferred embodiment have been set forth; the scope of the invention is not limited thereto, but rather by the scope of the attached claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Screen doors, storm doors and the like, are utilized on millions of homes to provide fresh air, weather protection, and security, etc. The door typically includes a means for closing the door such as a spring or piston assembly or the like. A popular means for controlling the door position utilizes a piston assembly which typically includes a cylindrical tube attached at one end to a bracket connector on the door. The inner surface of the cylindrical tube generally includes a spring loaded piston attached to a reciprocating connecting rod which extends from the piston and out of the tube. The end of the connecting rod opposite to the end carried and connected within the cylindrical tube typically is attached to a bracket which is connected to the door frame. When the door is opened, the connecting rod is pulled from the cylindrical tube, causing the piston to travel within the inner surface of the cylinder and thereby compress a spring coiled between an inner wall of the cylinder and the piston. When the door is released, energy stored within the spring pushes against the surface of the piston, causing it to slide within the cylinder and the connecting rod is drawn back within the cylindrical tube thereby closing the door. The retracting momentum of the piston is typically cushioned by compression of fluid such as air or oil inside the cylinder tube to create a damping resistance opposite the force that propels the door to close for better control of the speed and force at which the door closes. Many different devices have been invented in order to maintain the door in a certain position, i.e., partially or completely open. One such device is a hold-open washer which has an aperture through which the connecting rod extends. The hold-open rod must be manually set once the door is opened at a position along the connecting rod. After the door is released, the connecting rod begins to be drawn back within the cylinder and is stopped when the hold-open washer makes contact with the end of the cylinder, binding the hold-open washer against the piston rod. The door will remain held in place until the door is opened and the hold-open washer is manually repositioned transversely along the connecting piston rod and away from the cylindrical tube. U.S. Pat. No. 3,708,825 relates to a door check and door stop combination. The door check is made up of a pneumatic cylinder and piston which control the rate at which the door closes to prevent the door from slamming. A stop is attached to the distal end of the piston rod and lies along the side of the cylinder. The stop is made of a sheet material and has an aperture through it which receives the cylinder. The stop has a handle which may be engaged by the user's hand to move the stop from position in engagement with the cylinder. U.S. Pat. No. 4,639,969 relates to door closer mechanism for attachment to, or incorporation into, a standard spring type door closer, or for use with a standard spring type door closer. A reversible pawl and ratchet assembly operating on a rod between the door and door casing allows the door to ratchet open where it is held by the pawl until a slight closing pull or push on the door reverses action of the pawl and allows the door to close. While the door is closing or is fully closed, reopening of the door resets the pawl for again holding the door open as desired. U.S. Pat. No. 4,815,163 relates to a storm door lock apparatus set forth wherein a clamp is secured to an associated screen-door type closure member that further secures a slidable rod mounted with an abutment surface for actuation by a user with a pivoted lever at the other end of said rod for canting about a piston rod associated with a door closure. Additionally, a generally “L” shaped link is securable to the abutment member for allowing engagement and access by a user. U.S. Pat. No. 5,575,513 relates to a receptacle for propping the cylinder of a cylinder-and-plunger strut in extended position of the strut includes two side-by-side cylindrical chambers, one being of a size to embrace the jack plunger rod but not the jack cylinder and the other chamber being of a size to slide over the jack cylinder, which chambers are interconnected by a slot sufficiently narrower than the jack plunger rod to enable the receptacle to move into a position embracing the jack plunger rod by snap action, and the larger chamber being of a size to slide lengthwise over the cylinder and having in it a lengthwise slot sufficiently narrow so as not to be able to pass the cylinder through it but sufficiently wide to pass the plunger rod through it. U.S. Pat. No. 5,592,780 relates to an apparatus for controlling the position of a door suitable for use in association with door closing piston assemblies having a spring-biased reciprocable door closing piston rod and a latch plate transversely slidable along the length of the piston rod. U.S. Pat. No. 5,659,925 relates to a holding mechanism attached to a generic door closing cylinder. There are various disadvantages inherent in all of the prior art devices. To the Applicant's knowledge, none can be automatically locked open and released by simply moving the door without manual intervention. The prior art devices are often rather clumsy to manipulate when attempting to set or release a latch. Other disadvantages of the prior art devices are that they are rather complicated, hard to maintain, and expensive to produce. | <SOH> SUMMARY OF THE INVENTION <EOH>The present invention discloses and describes a device including a hold-open apparatus which can be used in combination with a screen or storm door piston assembly. Piston assemblies are commonly utilized in the industry to maintain or bias a door in a closed position. The hold-open apparatus is operatively connected at one end to the piston assembly, preferably a bracket thereof which is connected to a door casing or jamb. When the door is opened to a predetermined angle with respect to the door frame, a second end of the apparatus can be engaged with a cylinder end of the piston assembly and hold or maintain the door in an open position. Preferably the hold-open apparatus automatically engages and disengages the cylinder, unlike the prior art devices. The hold-open apparatus is of a durable and reliable construction and can be easily and efficiently manufactured. Importantly, the apparatus can be retrofitted to an existing storm or screen door with minimal effort. | 20050124 | 20060103 | 20050721 | 94928.0 | 0 | MAH, CHUCK Y | DOOR CLOSER HOLD-OPEN APPARATUS | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,041,357 | ACCEPTED | Selective polysilicon stud growth | A memory cell having a bit line contact is provided. The memory cell may be a 6F2 memory cell. The bit line contact may have a contact hole bounded by insulating sidewalls, and the contact hole may be partially or completely filled with a doped polysilicon plug. The doped polysilicon plug may have an upper plug surface profile that is substantially free of concavities or substantially convex. Similarly, a storage node contact may comprise a doped polysilicon plug having an upper plug surface profile that is substantially free of concavities or that is substantially convex. Additionally, a semiconductor device having a conductive contact comprising a polysilicon plug may is provided. The plug may contact a capacitor structure. | 1. A method of manufacturing a memory cell comprising an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact, said method comprising the steps of: forming said charge storage structure so as to be conductively coupled to said bit line via said transistor structure and said bit line contact; forming said transistor structure so as to be conductively coupled to said word line; forming said bit line contact by forming a conductively doped polysilicon plug within a contact hole bounded by insulating side walls; and forming said doped polysilicon plug by filling said contact hole to less than the uppermost extent of said insulating sidewalls with said conductively doped silicon plug such that said plug defines an upper plug surface profile substantially free of concavities in contact with said bit line. 2. A method of manufacturing a memory cell comprising an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact, said method comprising the steps of: forming said charge storage structure so as to be conductively coupled to said bit line via said transistor structure and said bit line contact; forming said transistor structure so as to be conductively coupled to said word line; forming said bit line contact by forming a conductively doped polysilicon plug within a contact hole bounded by insulating side walls; and forming said doped polysilicon plug by partially filling said contact hole with said conductively doped silicon plug such that said plug defines an upper plug surface profile substantially free of concavities in contact with said bit line. 3. A method of manufacturing a memory cell comprising an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact, said method comprising the steps of: forming said charge storage structure so as to be conductively coupled to said bit line via said transistor structure and said bit line contact; forming said transistor structure so as to be conductively coupled to said word line; forming said bit line contact by forming a conductively doped polysilicon plug within a contact hole bounded by insulating side walls; and forming said doped polysilicon plug by completely filling said contact hole with said conductively doped silicon plug such that said plug defines an upper plug surface profile substantially free of concavities in contact with said bit line. 4. A method of manufacturing a memory cell as claimed in claim 3, wherein said filling said contact hole with said conductively doped silicon plug is characterized by initial deposition and etch back of polysilicon in said contact hole and subsequent selective growth of conductively doped polysilicon in said contact hole. | CROSS REFERENCE TO RELATED APPLICATIONS The present application is a division of U.S. patent application Ser. No. 10/612,333, filed Jul. 2, 2003 (MIO 0033 V2/97-0917.03). This application, which is itself identified below for clarity, is also a member of the following family of related U.S. Patent Applications: No. 09/653,638, filed Oct. 4, 2001 (MIO 0033 PA/00-0917.00), now U.S. Pat. No. 6,380,576; No. 10/056,183, filed Jan. 24, 2002 (MIO 0033 VA/00-0917.01), now U.S. Pat. No. 6,660,584; No. 10/209,504, filed Jul. 31, 2002 (MIO 0033 NA/00-0917.02), now U.S. Pat. No. 6,649,962; No. 10/612,333, filed Jul. 2, 2003 (MIO 0033 V2/00-0917.03); No. 10/649,507, filed Aug. 22, 2003 (MIO 0033 V3/00-0917.04); No. 10/933,201, filed Sep. 2, 2004 (MIO 0033 IA/00-0917.05); and No. 10/986,246, filed Nov. 11, 2004 (MIO 0033 V4/00-0917.06); No. ______, filed ______ (MIO 0033 V5/00-0917.07); and No. ______, filed ______ (MIO 0033 V6/00-0917.08). BACKGROUND OF THE INVENTION The present invention relates to the fabrication of memory cell arrays and, more particularly, to the formation of a specialized bit line contact in the structure of a DRAM array. Conventional memory device arrays include word lines running generally in parallel along one direction and bit line pairs running generally in parallel along a perpendicular direction. The memory cell includes a charge storage structure connected by a transistor to one of the bit line pairs. Each transistor is activated by a word line. A row of memory cells is selected upon activation of a word line. The state of each memory cell in the row is transferred to a bit line for sensing by sense amplifiers, each of which is connected to a pair of bit lines. The memory cell transfer transistors are formed in the substrate in a plurality of continuous active areas running generally in parallel to each other. To form a transistor in an active area, impurity doped regions are formed in the substrate along the length of each active area 24 to create the source and drain of the transistor. A word line forms the gate of the transistor. The transistor formed in the active area provides the pass gate that is controllable to electrically connect the charge storage structure to a bit line. Thus, for example, activation of a word line will cause stored charges to be transferred by corresponding transistors to bit lines. The bit lines are electrically connected to a node of the transistor by bit line contacts. Conventional bit line contacts are formed through a multi-step deposition and etch back process that increases the complexity of the overall array fabrication process. The process is further complicated because the upper surface of the bit line contact, i.e., the surface that serves as the conductive interface with the bit line, defines a V-shaped profile. Accordingly, there is a need for a memory array fabrication scheme that presents a simplified bit line contact fabrication process. BRIEF SUMMARY OF THE INVENTION This need is met by the present invention wherein an improved bit line contact fabrication process is provided. In accordance with one embodiment of the present invention, a memory cell defined along first, second, and third orthogonal dimensions is provided. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. The storage node contact feature may also comprise a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. The insulating side walls may comprise a first pair of opposing insulating side walls along the first dimension and a second pair of opposing insulating side walls along the second dimension. The first pair of opposing insulating side walls may comprise respective layers of insulating spacer material formed over a conductive line. The second pair of opposing insulating side walls may comprise respective layers of insulating material formed between respective contact holes. The contact hole may be filled with the polysilicon plug to an uppermost extent of the insulating side walls. In accordance with another embodiment of the present invention, a memory cell array is provided including a plurality of memory cells, each of the memory cells being defined along first, second, and third orthogonal dimensions. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a computer system is provided comprising a microprocessor in communication with a memory device including a memory cell array, the memory cell array including a plurality of memory cells, each of the memory cells being defined along first, second, and third orthogonal dimensions. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a memory cell is provided comprising an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The charge storage structure is conductively coupled to the bit line via the transistor structure and the bit line contact. The transistor structure is conductively coupled to the word line. The bit line contact comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. The doped polysilicon plug defines a substantially convex upper plug surface profile in contact with the bit line. In accordance with yet another embodiment of the present invention, a memory cell array is provided comprising electrically conductive word lines and bit lines, an array of electrical charge storage structures, an array of transistor structures, an array of bit line contacts, and a plurality of sense amplifiers. Each of the charge storage structures is conductively coupled to one of the bit lines via a selected transistor structure and a selected bit line contact. Each of the transistor structures is conductively coupled to one of the word lines. Each of the bit lines are conductively coupled to one of the sense amplifiers. Each of the selected bit line contacts comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. Each of the doped polysilicon plugs define a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a computer system is provided comprising a microprocessor in communication with a memory device including a memory cell array, the memory cell array including electrically conductive word lines and bit lines, an array of electrical charge storage structures, an array of transistor structures, an array of bit line contacts, and a plurality of sense amplifiers. Each of the charge storage structures is conductively coupled to one of the bit lines via a selected transistor structure and a selected bit line contact. Each of the transistor structures is conductively coupled to one of the word lines. Each of the bit lines are conductively coupled to one of the sense amplifiers. Each of the selected bit line contacts comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. Each of the doped polysilicon plugs define a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention a memory cell is provided. The memory cell is defined along first, second, and third orthogonal dimensions and comprises an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The charge storage structure is conductively coupled to the bit line via the transistor structure and the bit line contact. The transistor structure is conductively coupled to the word line. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The insulating side walls comprise a first pair of opposing insulating side walls along the first dimension and a second pair of opposing insulating side walls along the second dimension. The first pair of opposing insulating side walls comprise respective layers of insulating spacer material formed over a conductive line. The second pair of opposing insulating side walls comprise respective layers of insulating material formed between respective contact holes. The contact hole is filled to an uppermost extent of the insulating side walls with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile in contact with the bit line. In accordance with yet another embodiment of the present invention, a method of manufacturing a memory cell defined along first, second, and third orthogonal dimensions is provided. The method comprises the steps of: forming, along the first dimension, one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature; forming, along the second dimension, two one-half field oxide features and one active area feature such that the first and second dimensions define a 6F2 memory cell; forming the bit line contact feature such that it is characterized by a contact hole bounded by insulating side walls; and filling the contact hole with a conductively doped polysilicon plug such that the plug defines a substantially convex upper plug surface profile. The step of filling the contact hole is preferably executed through selective growth of doped polysilicon in the contact hole. In accordance with yet another embodiment of the present invention, a method of manufacturing a memory cell is provided. The memory cell comprises an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The method comprises the steps of: forming the charge storage structure so as to be conductively coupled to the bit line via the transistor structure and the bit line contact; forming the transistor structure so as to be conductively coupled to the word line; forming the bit line contact by forming a conductively doped polysilicon plug within a contact hole bounded by insulating side walls; and forming the doped polysilicon plug so as to define a substantially convex upper plug surface profile in contact with the bit line. For the purposes of defining and describing the present invention, it is noted that a charge storage structure includes, among other things, a storage node contact structure and a capacitor structure. In accordance with additional embodiments of the present invention a memory cell and its method of manufacture, according to the present invention, also embodies storage node contacts formed from a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. Accordingly, it is an object of the present invention to provide improved bit line and storage node contacts and an improved bit line and storage node contact fabrication process. Other objects of the present invention will be apparent in light of the description of the invention embodied herein. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The following detailed description of the preferred embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which: FIG. 1 is a schematic illustration of a memory cell array circuit according to the present invention; FIG. 2 is a schematic illustration of the physical layout of a memory cell array according to the present invention; FIG. 3 is a cross sectional view of the physical layout of FIG. 2, taken along line 3-3 of FIG. 2; FIG. 4 is a cross sectional view of the physical layout of FIG. 2, taken along line 4-4 of FIG. 2; FIG. 5 is a cross sectional view of the physical layout of FIG. 2, taken along line 5-5 of FIG. 2; and FIGS. 6 is a schematic illustration of an alternative physical layout of a memory cell array according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic diagram of an exemplary memory array 20 in a memory device that includes word lines 26 running generally in parallel along one direction and bit line pairs 32 running generally in parallel along a perpendicular direction. A memory cell is represented schematically as a capacitor 8, and is connected by a transistor 9 to one of the bit line pairs 32. Each transistor 9 is activated by a word line 26 coupled to a word line driver 25. A row of memory cells 8 is selected upon activation of a word line 26. The state of each memory cell 8 in the row is transferred to a bit line 32 for sensing by sense amplifiers 35, each connected to a pair of bit lines 32. Respective cell plates 7 are illustrated schematically. Typically, as will be appreciated by those practicing the present invention and familiar with memory array structure, the bit lines 32 are twisted in the array 20. FIG. 2 shows the layout of a portion of the memory array of a semiconductor memory device. In the illustrated embodiment the memory device is a dynamic random access memory or DRAM. Other types of memory devices include synchronous DRAMs, video RAMs, or other modified versions of the DRAM. The memory array 20 includes a semiconductive substrate 22. As used in this document, a semiconductive substrate is defined to mean any construction comprising semiconductive material, including bulk semiconductive materials such as a semiconductive wafer, either alone or in assemblies comprising other materials thereon, and semiconductive material layers, either alone or in assemblies comprising other materials. The term substrate refers to any supporting structure, including the semiconductive substrates described above. The memory cell transfer transistors 9 are formed in the substrate 22 in a plurality of continuous active areas 24 running generally in parallel to each other. Each active area 24 is defined between isolation regions 34 disposed relative to the substrate 22 (see FIG. 3). To form a transistor in an active area, impurity doped regions are formed in the substrate along the length of each active area 24 to create the source and drain of the transistor. A word line 26 forms the gate of the transistor 9. The transistor 9 formed in the active area 24 provides the pass gate that is controllable to electrically connect a cell capacitor 102A, 102B, 102C, and 102D to a bit line 32 via a storage node contact 101A, 101B, 101C, 101D (see FIG. 2). Thus, for example, activation of a word line 26C will cause the stored charges from the capacitors 102A and 102B to be transferred by corresponding transistors 9 to bit lines 32, which are electrically connected to a node (the source or drain) of the transistor by bit contacts 100A, 100B, 100C, 100D. Although depicted as circles or squares in FIG. 2, the contacts 100, 101 can be of different shapes, and can take up the entire area of intersection between the bit lines 32 and the active area lines 24. For clarity, each illustrated continuous active area line 24 has been shown to extend to outside of the boundary of substrate 22 utilizing dashed lines. Each individual active area is designated separately as 24□, 24□□, and 24 □□□. To reduce the effective memory cell area while still maintaining ease of manufacture as discussed below, the continuous active areas 24□, 24□□, and 24□□□ are not straight or linear, but rather weave relative to the substrate within which they are formed such that bends are created in each active area line 24. The illustrated individual continuous active area lines extend generally horizontally across the page upon which FIG. 2 appears, but jog upwardly as depicted in FIG. 2 to form protruding portions 19. This jogging is repeated along the length of the active area line 24. Similarly, the bit lines 32, which are formed above the active area lines 24, also weave relative to the substrate 22 such that depressed portions 21 are formed in the bit lines. The bit lines 32 run generally along the same direction as the active areas 24, but the direction of the jog in the bit lines 32 is opposite to the jog of the active area lines 24. The jogging of the bit lines and active area lines form slanted portions 17 and 15, respectively. The bit contacts 100 are formed at the intersections of the bit lines 32 and the active area lines 24. Since the bit lines 32 and active area lines 24 are slanted with respect to each other in the region of each intersection, formation of the contact hole in which the bit contact 100 is formed is made easier. This is because of the increase in width W of the contact hole as compared to the width if both the active area lines 24 and bit lines 32 are generally straight. This difference in contact hole width becomes more important as the feature size of memory cells continues to decrease because contact holes with greater widths are generally more reliable. As depicted in FIG. 2, each of the bit lines 32 and active area lines 24 run generally along the X direction. The jogs in the bit lines and active area lines are formed at predetermined locations A-A, B-B, C-C, and D-D. At A-A, each active area line 24 bends upwards while each bit line 32 bends downwards. The angle of the bend can be set at, for example, about 18.5 □, although other angles are also possible. In addition, the directions of the active area and bit lines jogs can be switched. As further shown in FIG. 2, at B-B, each of the active area and bit lines bend back in the opposite directions of the corresponding bends at A-A such that both the active area and bit lines run again generally along the X direction. At C-C the active area and bit lines bend again, also in the opposite directions from the corresponding bends at A-A. At D-D, the lines bend back again to run generally in the X direction. One advantage of weaving both the active area and bit lines in the array is that a smaller bend angle is required for the repeated jogs while still achieving the desired memory cell area reduction. A plurality of conductive lines 26, 28 are formed under the bit lines 32 and run generally perpendicularly to the active area 24 and bit lines 32. In the illustrated example, four of the conductive lines are word lines 26 and one of the conductive lines 28 is grounded to provide isolation between storage nodes. A pair of conductive lines 26A, 26B, 26C, 26D may be seen on either side of conductive line 28 (see FIG. 2). The active area lines 24 and conductive lines 26, 28 constitute or define an array over which a plurality of memory cells are formed. The area which is consumed by a single memory cell in accordance with this embodiment is illustrated by dashed outline 30. This memory cell area can be described with reference to its feature size F. The feature size is based on the width L of the electrically conductive lines in the array, and on the width S of the isolation space between the conductive lines. The sum of L and S is the minimum pitch of the memory cell. The feature size F is half the minimum pitch, or half the sum of L and S. As is illustrated in FIG. 2, the memory cell 30 comprises a single memory cell that is about 3F wide (one-half bit line contact feature, one word line feature, one word line space feature, and one-half field poly line feature) by about 2F high (two one-half field oxide features and one active area feature), thus providing a consumed area for a single memory cell of about 6F2. In one implementation, F is no greater than 0.25 micrometer, and preferably, no greater than 0.18 micrometer. However, other dimensions, either larger or smaller, are also contemplated. It is noted that it is commonplace in the art of semiconductor fabrication to refer to a bit line and a digit line interchangeably. In one implementation, adjacent word lines 26 share an intervening bit contact 100 of adjacent pairs of memory cells as will become apparent below. For example, as shown in FIG. 2, word lines 26C and 26D share bit contacts 100A and 100B. Electrical isolation between the adjacent pairs of memory cells is provided by intervening conductive line 28. Line 28, in operation, is connected with ground or a suitable negative voltage. Alternatively, the electrical isolation can be provided by field oxide. Cross-sectional views of the memory array 20 of FIG. 2 are shown in FIGS. 3, 4, and 5, which are cross-sections taken along lines 3-3, 4-4, and 5-5, respectively. Referring to FIGS. 2-5, the bit contacts 100 comprise an electrically conductive plug 46 made of a conductively doped polysilicon and electrically connect the bit lines 32 to the underlying active areas 24. The storage node contacts 101 also comprise an electrically conductive plug 37 made of a conductively doped polysilicon. The bit contacts 100 are located in the space 104 between two adjacent word lines 26. The memory cell capacitors 102 are electrically contacted to the active areas 24 via the electrically conductive plugs 37. In FIG. 3, the active areas 24 are defined in the substrate 22. The electrically conductive plugs 46 are disposed above and in electrical contact with portions of the active areas 24. The bit lines 32 are conventional electrically conductive multilayer structures formed from conventional materials and typically comprise, for example, a conductive layer 50, a conductive barrier layer 52, and an insulator 54. The bit lines 32 are disposed above and in electrical contact with the bit line contact plugs 46. A layer of insulating spacer material 58 is formed over the multilayer structures to electrically insulate exposed portions of the multilayer structures. Referring to FIG. 4, an enlarged view of the array taken generally along line 4-4 in FIG. 2 is shown. The bit line 32 overlies conductive lines 26, 28 and associated isolation oxide regions 34 and insulating regions 48. Bit line 32 can also be seen to be in electrical communication with the two illustrated plugs 46. The storage node plugs 37 are also illustrated in FIG. 4. In FIG. 5, the cell capacitors 102 are illustrated. Each capacitor 102 is formed of a first capacitor plate 64, a dielectric layer 66, and a second capacitor plate 68. The first capacitor plate 64 of each cell is electrically contacted to the plug 46 for electrical connection to the active area 24. The cell capacitor structure is laid over the bit line structure, which forms a cell-over-bit line (COB) array structure. An advantage the COB structure offers is that bit line contact openings need not be made in the second capacitor plate 68, which eliminates difficulties associated with aligning bit line contact openings in the second plate 68 to cell structures or word lines in the array and allows for maximization of the cell capacitor area, as is illustrated in FIG. 2 (see 102A, 102B, 102C, 102D). The bit line structure is referred to as a buried bit line and corresponds to the bit line 32 in FIG. 2. Referring again to FIG. 2, the memory array structure of the present invention includes a plurality of memory cells 30. As is described above, each of the memory cells 30 comprises a 6F2 memory cell defined along three orthogonal dimensions, two of which are indicated in FIG. 2 (see X, Y). As is illustrated in FIGS. 3, 4, and 5, the bit line contact feature of the memory cell 30 is characterized by a contact hole bounded by insulating side walls. Specifically, the insulating side walls comprise a first pair of opposing insulating side walls 31 along the first dimension X and a second pair of opposing insulating side walls 36 along the second dimension Y. The first pair of opposing insulating side walls 31 comprise respective layers of insulating spacer material formed over the word lines 26. The second pair of opposing insulating side walls 36 comprise respective layers of insulating material formed between respective contact holes. The contact holes are filled with the conductively doped polysilicon plug 46. The plug is formed so as to define a substantially convex upper plug surface profile in contact with the bit line 32. The upper plug surface profile is described herein as substantially convex because it is contemplated that the profile may vary from a uniformly pure convex profile. Specifically, the profile may include irregularities in the form of bumps or pits and may include portions that are not convex. For the purposes of defining and describing the present invention, it is noted that a “substantially convex” plug profile includes a portion within the interior of its periphery that extends beyond a plane defined by the periphery of the plug. It is further contemplated by the present invention that, in certain embodiments, it may be sufficient to form a plug profile that is substantially flat. Accordingly, for the purposes of defining and describing the present invention, it is noted that a “substantially convex” plug profile also includes any plug profile that is essentially flat or free of significant concavities. Preferably, the contact holes are filled with the conductively doped polysilicon plug 46 to an uppermost extent of the insulating side walls 36 in a selective doped polysilicon growth process. The storage node plugs 37 may be formed in a similar manner. It is contemplated by the present invention that the contact holes may initially be partially filled via conventional deposition techniques and subsequently topped off via a selective doped polysilicon growth process according to the present invention. For example, a contact hole may initially be filled by depositing polysilicon in a conventional manner, etching back the deposited polysilicon, and subsequently executing a selective doped polysilicon growth process according to the present invention to yield the convex plug profile of the present invention. Advancement in deposition systems has enabled selective growth of polysilicon films. In selective growth, films are grown through holes in films of silicon dioxide, silicon nitride, oxynitride, or any insulator material that inhibits silicon growth. The wafer at issue is positioned in a reactor chamber and the film grows directly on the silicon exposed on the bottom of the hole. As the film grows, in the insulating side wall contact hole structure of the present invention, it assumes the substantially convex upper plug surface profile illustrated in FIGS. 3-5. As will be appreciated by those practicing the present invention and familiar with the art of semiconductor device fabrication, a variety of polysilicon growth techniques may be utilized to form the substantially convex upper plug surface profile of the present invention. For example, according to one embodiment of the present invention, the polysilicon plug 46 may be grown by using a silicon source of silane or disilane at a temperature of about 500□C and a pressure of about 100-200 mT. The polycrystalline silicon may be n-type or p-type and may be doped with conventional n or p-type dopants, including arsenic, phosphorous, boron, indium, etc. In one embodiment, a “double deck” bit line architecture is used, which includes the buried bit line and a top deck bit line 32′ formed above the buried bit lines 32 and the capacitors 102 (see FIG. 3). As shown in FIG. 3, an insulating layer 39 is formed between the top deck bit line 32′ and the underlying structure. The top deck bit line 32′ is generally formed of a metal, such as aluminum. The top deck bit lines 32′ do not make contact with the memory array. Contact to the memory array transistors are made by the buried bit lines 32. By using the double deck bit line structure, the bit lines 32, 32′ can be connected to the sense amplifiers 35 in a folded bit line configuration. Thus, by using the double deck bit lines, the 6F2 memory cell described in this application can be used in a folded bit line memory configuration. One advantage of the folded bit line configuration is that it is less susceptible to charge coupling between bit lines. Because a bit line pair is connected to each sense amplifier 35 on the same side of the sense amplifier, noise created by alpha particles will couple to both of the bit lines in the pair. As the sense amplifier 35 detects the difference in voltage between the pair of bit lines, errors due to such noise effects, commonly referred to as common mode rejection, are reduced. Referring to FIG. 6, an alternative embodiment of an array containing reduced size memory cells (e.g., 6F2 cells) is shown. In this configuration, bit lines 200 are formed to weave relative to the substrate 20, while continuous active area lines 202 are generally straight. Bit contacts 206 are formed at the intersections between the bit lines 200 and active area lines 202. In addition, memory cell capacitors 208 are formed over and are in electrical contact with portions of the active area lines 202 via storage node contacts 207. As illustrated, each bit line 200 runs generally in the X direction and jogs or protrudes upwardly in a repeated pattern. Each bit line 200 bends upwardly at A-A at an angle of about 45 □ with respect to the X axis. The bit line 200 then bends in the opposite direction at B-B so that it runs generally in the X direction. After a short run, the bit line 200 then bends downwardly at C-C. At D-D, the bit line 200 again bends back to run generally in the X direction. This pattern is repeated throughout the memory array. As indicated by the dashed outline 210, the feature size of the memory cell in this configuration is also about 6F2. Conductive lines 204, 205 run generally perpendicularly to the active areas 202. The conductive lines 204 form the word lines in the array while the lines 205 are grounded or driven to a negative voltage to provide electrical isolation between word lines 204. It is contemplated by the present invention that an additional alternative memory cell configuration may utilize straight bit lines and active area lines that weave relative to the bit lines. In this embodiment, continuous active areas would run generally in the X direction and have repeated downward jogs, creating weaving continuous active areas. Active areas may be defined by isolation regions relative to a substrate, which initially is on a flat surface of a wafer. Because of the flatness, the bends in the active areas do not create as many photolithographic difficulties as with bit lines, which generally run over relatively rough terrain since the bit lines make contact to the active area surface in some portions and are isolated from active areas where the cell capacitors are formed. Having described the invention in detail and by reference to preferred embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. For example, although much of the present invention is illustrated with reference to folded bit line structure, it is noted that the present invention is applicable to open bit line architecture as well. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to the fabrication of memory cell arrays and, more particularly, to the formation of a specialized bit line contact in the structure of a DRAM array. Conventional memory device arrays include word lines running generally in parallel along one direction and bit line pairs running generally in parallel along a perpendicular direction. The memory cell includes a charge storage structure connected by a transistor to one of the bit line pairs. Each transistor is activated by a word line. A row of memory cells is selected upon activation of a word line. The state of each memory cell in the row is transferred to a bit line for sensing by sense amplifiers, each of which is connected to a pair of bit lines. The memory cell transfer transistors are formed in the substrate in a plurality of continuous active areas running generally in parallel to each other. To form a transistor in an active area, impurity doped regions are formed in the substrate along the length of each active area 24 to create the source and drain of the transistor. A word line forms the gate of the transistor. The transistor formed in the active area provides the pass gate that is controllable to electrically connect the charge storage structure to a bit line. Thus, for example, activation of a word line will cause stored charges to be transferred by corresponding transistors to bit lines. The bit lines are electrically connected to a node of the transistor by bit line contacts. Conventional bit line contacts are formed through a multi-step deposition and etch back process that increases the complexity of the overall array fabrication process. The process is further complicated because the upper surface of the bit line contact, i.e., the surface that serves as the conductive interface with the bit line, defines a V-shaped profile. Accordingly, there is a need for a memory array fabrication scheme that presents a simplified bit line contact fabrication process. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>This need is met by the present invention wherein an improved bit line contact fabrication process is provided. In accordance with one embodiment of the present invention, a memory cell defined along first, second, and third orthogonal dimensions is provided. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F 2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. The storage node contact feature may also comprise a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. The insulating side walls may comprise a first pair of opposing insulating side walls along the first dimension and a second pair of opposing insulating side walls along the second dimension. The first pair of opposing insulating side walls may comprise respective layers of insulating spacer material formed over a conductive line. The second pair of opposing insulating side walls may comprise respective layers of insulating material formed between respective contact holes. The contact hole may be filled with the polysilicon plug to an uppermost extent of the insulating side walls. In accordance with another embodiment of the present invention, a memory cell array is provided including a plurality of memory cells, each of the memory cells being defined along first, second, and third orthogonal dimensions. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F 2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a computer system is provided comprising a microprocessor in communication with a memory device including a memory cell array, the memory cell array including a plurality of memory cells, each of the memory cells being defined along first, second, and third orthogonal dimensions. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F 2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The contact hole is filled with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a memory cell is provided comprising an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The charge storage structure is conductively coupled to the bit line via the transistor structure and the bit line contact. The transistor structure is conductively coupled to the word line. The bit line contact comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. The doped polysilicon plug defines a substantially convex upper plug surface profile in contact with the bit line. In accordance with yet another embodiment of the present invention, a memory cell array is provided comprising electrically conductive word lines and bit lines, an array of electrical charge storage structures, an array of transistor structures, an array of bit line contacts, and a plurality of sense amplifiers. Each of the charge storage structures is conductively coupled to one of the bit lines via a selected transistor structure and a selected bit line contact. Each of the transistor structures is conductively coupled to one of the word lines. Each of the bit lines are conductively coupled to one of the sense amplifiers. Each of the selected bit line contacts comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. Each of the doped polysilicon plugs define a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention, a computer system is provided comprising a microprocessor in communication with a memory device including a memory cell array, the memory cell array including electrically conductive word lines and bit lines, an array of electrical charge storage structures, an array of transistor structures, an array of bit line contacts, and a plurality of sense amplifiers. Each of the charge storage structures is conductively coupled to one of the bit lines via a selected transistor structure and a selected bit line contact. Each of the transistor structures is conductively coupled to one of the word lines. Each of the bit lines are conductively coupled to one of the sense amplifiers. Each of the selected bit line contacts comprises a conductively doped polysilicon plug formed within a contact hole bounded by insulating side walls. Each of the doped polysilicon plugs define a substantially convex upper plug surface profile. In accordance with yet another embodiment of the present invention a memory cell is provided. The memory cell is defined along first, second, and third orthogonal dimensions and comprises an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The charge storage structure is conductively coupled to the bit line via the transistor structure and the bit line contact. The transistor structure is conductively coupled to the word line. The first dimension is characterized by one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature. The second dimension is characterized by two one-half field oxide features and one active area feature. The first and second dimensions define a 6F 2 memory cell. The bit line contact feature is characterized by a contact hole bounded by insulating side walls. The insulating side walls comprise a first pair of opposing insulating side walls along the first dimension and a second pair of opposing insulating side walls along the second dimension. The first pair of opposing insulating side walls comprise respective layers of insulating spacer material formed over a conductive line. The second pair of opposing insulating side walls comprise respective layers of insulating material formed between respective contact holes. The contact hole is filled to an uppermost extent of the insulating side walls with a conductively doped polysilicon plug defining a substantially convex upper plug surface profile in contact with the bit line. In accordance with yet another embodiment of the present invention, a method of manufacturing a memory cell defined along first, second, and third orthogonal dimensions is provided. The method comprises the steps of: forming, along the first dimension, one-half of a bit line contact feature, one word line feature, one word line space feature, and one-half of a field poly line feature; forming, along the second dimension, two one-half field oxide features and one active area feature such that the first and second dimensions define a 6F 2 memory cell; forming the bit line contact feature such that it is characterized by a contact hole bounded by insulating side walls; and filling the contact hole with a conductively doped polysilicon plug such that the plug defines a substantially convex upper plug surface profile. The step of filling the contact hole is preferably executed through selective growth of doped polysilicon in the contact hole. In accordance with yet another embodiment of the present invention, a method of manufacturing a memory cell is provided. The memory cell comprises an electrically conductive word line, an electrically conductive bit line, an electrical charge storage structure, a transistor structure, and a bit line contact. The method comprises the steps of: forming the charge storage structure so as to be conductively coupled to the bit line via the transistor structure and the bit line contact; forming the transistor structure so as to be conductively coupled to the word line; forming the bit line contact by forming a conductively doped polysilicon plug within a contact hole bounded by insulating side walls; and forming the doped polysilicon plug so as to define a substantially convex upper plug surface profile in contact with the bit line. For the purposes of defining and describing the present invention, it is noted that a charge storage structure includes, among other things, a storage node contact structure and a capacitor structure. In accordance with additional embodiments of the present invention a memory cell and its method of manufacture, according to the present invention, also embodies storage node contacts formed from a conductively doped polysilicon plug defining a substantially convex upper plug surface profile. Accordingly, it is an object of the present invention to provide improved bit line and storage node contacts and an improved bit line and storage node contact fabrication process. Other objects of the present invention will be apparent in light of the description of the invention embodied herein. | 20050124 | 20071113 | 20050609 | 69282.0 | 0 | TRINH, MICHAEL MANH | SELECTIVE POLYSILICON STUD GROWTH | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,041,444 | ACCEPTED | Methods and systems for synchronizing visualizations with audio streams | Methods and systems are described that assist media players in rendering visualizations and synchronizing those visualizations with audio samples. In one embodiment, visualizations are synchronized with an audio stream using a technique that builds and maintains various data structures. Each data structure can maintain data that is associated with a particular pre-processed audio sample. The maintained data can include a timestamp that is associated with a time when the audio sample is to be rendered. The maintained data can also include various characteristic data that is associated with the audio stream. When a particular audio sample is being rendered, its timestamp is used to locate a data structure having characteristic data. The characteristic data is then used in a visualization rendering process to render a visualization. | 1. A system for synchronizing a visualization with audio samples comprising: first means configured to receive and preprocess audio samples before the samples are rendered by a renderer that comprises part of a media player, the first means preprocessing the samples to provide characterizing data derived from each sample, the characterizing data comprising a timestamp associated with each audio sample, the timestamp being assigned in accordance with when the audio sample is calculated to be rendered by the renderer, wherein the first means comprises a Fast Fourier Transform that it utilizes to process the audio samples to provide frequency data associated with the audio samples; second means to hold the characterizing data, each second means being associated with an audio sample; third means configured to call the first means to ascertain the characterizing data associated with an audio sample that is currently being rendered by the renderer; the first means being configured to ascertain said characterizing data by querying the renderer for a time associated with the currently-rendered audio sample, and then using said time to identify a data structure having a timestamp that is nearest in value to said time; and fourth means configured to receive characterizing data that is associated with the second means having the timestamp that is nearest in value to said time, and use the characterizing data to render a visualization that is synchronized with the audio sample that is being rendered by the renderer. 2. The system of claim 1, wherein the characterizing data comprises frequency data. 3. The system of claim 1, wherein the visualization is rendered in a rendering area in which other media types can be rendered. 4. The system of claim 3, wherein the other media types comprise a video type. 5. The system of claim 3, wherein the other media types comprise a skin type. 6. The system of claim 3, wherein the other media types comprise a HTML type. 7. The system of claim 3, wherein the other media types comprise an animation type. 8. A system for providing a visualization comprising: means for receiving multiple audio samples; means for pre-processing the audio samples before they are rendered by a media player renderer, the pre-processing deriving characterizing data from each sample, wherein the characterizing data comprises a timestamp associated with the audio sample, the timestamp being provided based upon when the audio sample is calculated to be rendered by the media player renderer; means for maintaining characterizing data for each audio sample in a data structure associated with each audio sample; means for determining when an audio sample is being rendered by the media player renderer, wherein said means for determining comprises: means for ascertaining a time associated with a currently-rendered audio sample; means for selecting a data structure having a timestamp that is nearest the time; and means for providing characterizing data associated with the selected data structure to a component configured to provide the visualization; and means for using the characterizing data that is associated with the audio sample that is being rendered to provide a visualization. 9. The system of claim 8, wherein the characterizing data comprises frequency data associated with each sample. 10. The system of claim 8, wherein said means for pre-processing comprises means for using a Fast Fourier Transform to provide frequency data associated with the samples. 11. A system for providing a visualization comprising: means for defining a frame rate at which visualization frames of a visualization are to be rendered, the visualization frames being rendered from characterizing data that is computed from audio samples and which is used to create the visualization; means for setting a threshold associated with an amount of time that is to be spent rendering a visualization frame; means for monitoring the time associated with rendering individual visualization frames; means for determining whether a visualization frame rendering time exceeds the threshold; and means for providing an effective frame rate for rendering visualization frames that is longer than the defined frame rate if the determined visualization frame rendering time exceeds the threshold. 12. The system of claim 1 1, wherein said means for providing comprises means for increasing a call interval associated with calls that are made to a visualization-rendering component. 13. The system of claim 11 further comprising means for modifying the effective frame rate so that the visualization frames are rendered at the defined frame rate. | RELATED APPLCATIONS This application is a continuation of and claims priority to U.S. patent application Ser. No. 09/817,902, filed on Mar. 26, 2001, the disclosure of which is incorporated by reference herein. TECHNICAL FIELD This invention relates to methods and systems for synchronizing visualizations with audio streams. BACKGROUND Today, individuals are able to use their computers to download and play various media content. For example, many companies offer so-called media players that reside on a computer and allow a user to download and experience a variety of media content. For example, users can download media files associated with music and listen to the music via their media player. Users can also download video data and animation data and view these using their media players. One problem associated with prior art media players is they all tend to display different types of media in different ways. For example, some media players are configured to provide a “visualization” when they play audio files. A visualization is typically a piece of software that “reacts” to the audio that is being played by providing a generally changing, often artistic visual display for the user to enjoy. Visualizations are often presented, by the prior art media players, in a window that is different from the media player window or on a different portion of the user's display. This causes the user to shift their focus away from the media player and to the newly displayed window. In a similar manner, video data or video streams are often provided within yet another different window which is either an entirely new display window to which the user is “flipped”, or is a window located on a different portion of the user's display. Accordingly, these different windows in different portions of the user's display all combine for a fairly disparate and unorganized user experience. It is always desirable to improve the user's experience. In addition, there are problems associated with prior art visualizations. As an example, consider the following. One of the things that makes visualizations enjoyable and interesting for users is the extent to which they “mirror” or follow the audio being played on the media player. Past visualization technology has led to visualizations that do not mirror or follow the audio as closely as one would like. This leads to things such as a lag in what the user sees after they have heard a particular piece of audio. It would be desirable to improve upon this media player feature. Accordingly, this invention arose out of concerns associated with providing improved media players and user experiences regarding the same. SUMMARY Methods and systems are described that assist media players in rendering different media types. In some embodiments, a unified rendering area is provided and managed such that multiple different media types are rendered by the media player in the same user interface area. This unified rendering area thus permits different media types to be presented to a user in an integrated and organized manner. An underlying object model promotes the unified rendering area by providing a base rendering object that has properties that are shared among the different media types. Object sub-classes are provided and are each associated with a different media type, and have properties that extend the shared properties of the base rendering object. In addition, an inventive approach to visualizations is presented that provides better synchronization between a visualization and its associated audio stream. In one embodiment, visualizations are synchronized with an audio stream using a technique that builds and maintains various data structures. Each data structure can maintain data that is associated with a particular audio sample. The maintained data can include a timestamp that is associated with a time when the audio sample is to be rendered. The maintained data can also include various characteristic data that is associated with the audio stream. When a particular audio sample is being rendered, its timestamp is used to locate a data structure having characteristic data. The characteristic data is then used in a visualization rendering process to render a visualization. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is block diagram of a system in which various embodiments can be implemented. FIG. 2 is a block diagram of an exemplary server computer. FIG. 3 is a block diagram of an exemplary client computer. FIG. 4 is a diagram of an exemplary media player user interface (UI) that can be provided in accordance with one embodiment. The UI illustrates a unified rendering area in accordance with one embodiment. FIG. 5 is a flow diagram that describes steps in a method in accordance with one embodiment. FIG. 6 is a block diagram that helps to illustrate an object model in accordance with one embodiment. FIG. 7 is a flow diagram that describes steps in a method in accordance with one embodiment. FIG. 8 is a block diagram that illustrates an exemplary system for synchronizing a visualization with audio samples in accordance with one embodiment. FIG. 9 is a block diagram that illustrates exemplary components of a sample pre-processor in accordance with one embodiment. FIG. 10 is a flow diagram that describes steps in a method in accordance with one embodiment. FIG. 11 is a flow diagram that describes steps in a method in accordance with one embodiment. FIG. 12 is a flow diagram that describes steps in a method in accordance with one embodiment. FIG. 13 is a timeline that is useful in understanding aspects of one embodiment. FIG. 14 is a timeline that is useful in understanding aspects of one embodiment. FIG. 15 is a timeline that is useful in understanding aspects of one embodiment. DETAILED DESCRIPTION Overview Methods and systems are described that assist media players in rendering different media types. In some embodiments, a unified rendering area is provided and managed such that multiple different media types are rendered by the media player in the same user interface area. This unified rendering area thus permits different media types to be presented to a user in an integrated and organized manner. An underlying object model promotes the unified rendering area by providing a base rendering object that has properties that are shared among the different media types. Object sub-classes are provided and are each associated with a different media type, and have properties that extend the shared properties of the base rendering object. In addition, an inventive approach to visualizations is presented that provides better synchronization between a visualization and its associated audio stream. Exemplary System FIG. 1 shows exemplary systems and a network, generally at 100, in which the described embodiments can be implemented. The systems can be implemented in connection with any suitable network. In the embodiment shown, the system can be implemented over the public Internet, using the World Wide Web (WWW or Web), and its hyperlinking capabilities. The description herein assumes a general knowledge of technologies relating to the Internet, and specifically of topics relating to file specification, file retrieval, streaming multimedia content, and hyperlinking technology. System 100 includes one or more clients 102 and one or more network servers 104, all of which are connected for data communications over the Internet 106. Each client and server can be implemented as a personal computer or a similar computer of the type that is typically referred to as “IBM-compatible.” An example of a server computer 104 is illustrated in block form in FIG. 2 and includes conventional components such as a data processor 200; volatile and non-volatile primary electronic memory 202; secondary memory 204 such as hard disks and floppy disks or other removable media; network interface components 206; display devices interfaces and drivers 208; and other components that are well known. The computer runs an operating system 210 such as the Windows NT operating system. The server can also be configured with a digital rights management module 212 that is programmed to provide and enforce digital rights with respect to multimedia and other content that it sends to clients 102. Such digital rights can include, without limitation, functionalities including encryption, key exchange, license delivery and the like. Network servers 104 and their operating systems can be configured in accordance with known technology, so that they are capable of streaming data connections with clients. The servers include storage components (such as secondary memory 204), on which various data files are stored and formatted appropriately for efficient transmission using known protocols. Compression techniques can be desirably used to make the most efficient use of limited Internet bandwidth. FIG. 3 shows an example of a client computer 102. Various types of clients can be utilized, such as personal computers, palmtop computers, notebook computers, personal organizers, etc. Client computer 104 includes conventional components similar to those of network server 104, including a data processor 300; volatile and non-volatile primary electronic memory 301; secondary memory 302 such as hard disks and floppy disks or other removable media; network interface components 303; display devices interfaces and drivers 304; audio recording and rendering components 305; and other components as are common in personal computers. In the case of both network server 104 and client computer 102, the data processors are programmed by means of instructions stored at different times in the various computer-readable storage media of the computers. Programs are typically distributed, for example, on floppy disks or CD-ROMs. From there, they are installed or loaded into the secondary memory of a computer. At execution, they are loaded at least partially into the computer's primary electronic memory. The embodiments described herein can include these various types of computer-readable storage media when such media contain instructions or programs for implementing the described steps in conjunction with a microprocessor or other data processor. The embodiments can also include the computer itself when programmed according to the methods and techniques described below. For purposes of illustration, programs and program components are shown in FIGS. 2 and 3 as discrete blocks within a computer, although it is recognized that such programs and components reside at various times in different storage components of the computer. Client 102 is desirably configured with a consumer-oriented operating system 306, such as one of Microsoft Corporation's Windows operating systems. In addition, client 102 can run an Internet browser 307, such as Microsoft's Internet Explorer. Client 102 can also include a multimedia data player or rendering component 308. An exemplary multimedia player is Microsoft's Media Player 7. This software component can be capable of establishing data connections with Internet servers or other servers, and of rendering the multimedia data as audio, video, visualizations, text, HTML and the like. Player 308 can be implemented in any suitable hardware, software, firmware, or combination thereof. In the illustrated and described embodiment, it can be implemented as a standalone software component, as an ActiveX control (ActiveX controls are standard features of programs designed for Windows operating systems), or any other suitable software component. In the illustrated and described embodiment, media player 308 is registered with the operating system so that it is invoked to open certain types of files in response to user requests. In the Windows operating system, such a user request can be made by clicking on an icon or a link that is associated with the file types. For example, when browsing to a Web site that contains links to certain music for purchasing, a user can simply click on a link. When this happens, the media player can be loaded and executed, and the file types can be provided to the media player for processing that is described below in more detail. Exemplary Media Player UI FIG. 4 shows one exemplary media player user interface (UI) 400 that comprises part of a media player. The media player UI includes a menu 402 that can be used to manage the media player and various media content that can be played on and by the media player. Drop down menus are provided for file management, view management, play management, tools management and help management. In addition, a set of controls 404 are provided that enable a user to pause, stop, rewind, fast forward and adjust the volume of media that is currently playing on the media player. A rendering area or pane 406 is provided in the UI and serves to enable multiple different types of media to be consumed and displayed for the user. The rendering area is highlighted with dashed lines. In the illustrated example, the U2 song “Beautiful Day” is playing and is accompanied by some visually pleasing art as well as information concerning the track. In one embodiment, all media types that are capable of being consumed by the media player are rendered in the same rendering area. These media types include, without limitation, audio, video, skins, borders, text, HTML and the like. Skins are discussed in more detail in U.S. patent applications Ser. Nos. 09/773,446 and 09/773,457, the disclosures of which are incorporated by reference. Having a unified rendering area provides an organized and integrated user experience and overcomes problems associated with prior art media players discussed in the “Background” section above. FIG. 5 is a flow diagram that describes steps in a method of providing a user interface in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware or combination thereof. In the described embodiment, the method is implemented in software. Step 500 provides a media player user interface. This step is implemented in software code that presents a user interface to the user when a media player application is loaded and executed. Step 502 provides a unified rendering area in the media player user interface. This unified rendering area is provided for rendering different media types for the user. It provides one common area in which the different media types can be rendered. In one embodiment, all visual media types that are capable of being rendered by the media player are rendered in this area. Step 504 then renders one or more different media types in the unified rendering area. Although the method of FIG. 5 can be implemented in any suitable software using any suitable software programming techniques, the illustrated and described method is implemented using a common runtime model that unifies multiple (or all) media type rendering under one common rendering paradigm. In this model, there are different components that render the media associated with the different media types. The media player application, however, hosts all of the different components in the same area. From a user's perspective, then, all of the different types of media are rendered in the same area. Exemplary Object Model FIG. 6 shows components of an exemplary object model in accordance with one embodiment generally at 600. Object model 600 enables different media types to be rendered in the same rendering area on a media player UI. The object model has shared attributes that all objects support. Individual media type objects have their own special attributes that they support. Examples of these attributes are given below. The object model includes a base object called a “rendering object” 602. Rendering object 602 manages and defines the unified rendering area 406 (FIG. 4) where all of the different media types are rendered. In addition to rendering object 602, there are multiple different media type rendering objects that are associated with the different media types that can get rendered the unified rendering area. In the illustrated and described embodiment, these other rendering objects include, without limitation, a skin rendering object 604, a video rendering object 606, an audio rendering object 608, an animation rendering object 610, and an HTML rendering object 612. It should be noted that some media type rendering objects can themselves host a rendering object. For example, skin rendering object 604 can host a rendering object within it such that other media types can be rendered within the skin. For example, a skin can host a video rendering object so that video can be rendered within a skin. It is to be appreciated and understood that other rendering objects associated with other media types can be provided. Rendering objects 604-612 are subclasses of the base object 602. Essentially then, in this model, rendering object 602 defines the unified rendering area and each of the individual rendering objects 604-612 define what actually gets rendered in this area. For example, below each of objects 606, 608, and 610 is a media player skin 614 having a unified rendering area 406. As can be seen, video rendering object 606 causes video data to be rendered in this area; audio rendering object 608 causes a visualization to be rendered in this area; and animation rendering object 610 causes text to be rendered in this area. All of these different types of media are rendered in the same location. In this model, the media player application can be unaware of the specific media type rendering objects (i.e. objects 604-612) and can know only about the base object 602. When the media player application receives a media type for rendering, it calls the rendering object 602 with the particular type of media. The rendering object ascertains the particular type of media and then calls the appropriate media type rendering object and instructs the object to render the media in the unified rendering area managed by rendering object 602. As an example, consider the following. The media player application receives video data that is to be rendered by the media player application. The application calls the rendering object 602 and informs it that it has received video data. Assume also that the rendering object 602 controls a rectangle that defines the unified rendering area of the UI. The rendering object ascertains the correct media type rendering object to call (here, video rendering object 606), call the object 606, and instructs object 606 to render the media in the rectangle (i.e. the unified rendering area) controlled by the rendering object 602. The video rendering object then renders the video data in the unified rendering area thus providing a UI experience that looks like the one shown by skin 614 directly under video rendering object 606. Common Runtime Properties In the above object model, multiple media types share common runtime properties. In the described embodiment, all media types share these properties: Attribute Description clippingColor Specifies or retrieves the color to clip out from the clippingImage bitmap. clippingImage Specifies or retrieves the region to clip the control to. elementType Retrieves the type of the element (for instance, BUTTON). enabled Specifies or retrieves a value indicating whether the control is enabled or disabled. height Specifies or retrieves the height of the control. horizontalAlignment Specifies or retrieves the horizontal alignment of the control when the VIEW or parent SUBVIEW is resized. id Specifies or retrieves the identifier of a control. Can only be set at design time. left Specifies or retrieves the left coordinate of the control. passThrough Specifies or retrieves a value indicating whether the control will pass all mouse events through to the control under it. tabStop Specifies or retrieves a value indicating whether the control will be in the tabbing order. top Specifies or retrieves the top coordinate of the control. verticalAlignment Specifies or retrieves the vertical alignment of the control when the VIEW or parent SUBVIEW is resized. visible Specifies or retrieves the visibility of the control. width Specifies or retrieves the width of the control. zIndex Specifies or retrieves the order in which the control is rendered. Examples of video-specific settings that extend these properties for video media types include: Attribute Description backgroundColor Specifies or retrieves the background color of the Video control. cursor Specifies or retrieves the cursor value that is used when the mouse is over a clickable area of the video. fullScreen Specifies or retrieves a value indicating whether the video is displayed in full-screen mode. Can only be set at run time. maintainAspectRatio Specifies or retrieves a value indicating whether the video will maintain the aspect ratio when trying to fit within the width and height defined for the control. shrinkToFit Specifies or retrieves a value indicating whether the video will shrink to the width and height defined for the Video control. stretchToFit Specifies or retrieves a value indicating whether the video will stretch itself to the width and height defined for the Video control. toolTip Specifies or retrieves the ToolTip text for the video window. windowless Specifies or retrieves a value indicating whether the Video control will be windowed or windowless; that is, whether the entire rectangle of the control will be visible at all times or can be clipped. Can only be set at design time. zoom Specifies the percentage by which to scale the video. Examples of audio-specific settings that extend these properties for audio media types include: Attribute Description allowAll Specifies or retrieves a value indicating whether to include all the visualizations in the registry. currentEffect Specifies or retrieves the current visualization. currentEffectPresetCount Retrieves number of available presets for the current visualization. currentEffectTitle Retrieves the display title of the current visualization. currentEffectType Retrieves the registry name of the current visualization. currentPreset Specifies or retrieves the current preset of the current visualization. currentPresetTitle Retrieves the title of the current preset of the current visualization. effectCanGoFullScreen Retrieves a value indicating whether the current visualization can be displayed full-screen. Exemplary Method FIG. 7 is a flow diagram that describes steps in a media rendering method in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware, or combination thereof. In the illustrated and described embodiment, the method is implemented in software. This software can comprise part of a media player application program executing on a client computer. Step 700 provides a base rendering object that defines a unified rendering area. The unified rendering area desirably provides an area within which different media types can be rendered. These different media types can comprise any media types that are typically rendered or renderable by a media player. Specific non-limiting examples are given above. Step 702 provides multiple media-type rendering objects that are subclasses of the base rendering objects. These media-type rendering objects share common properties among them, and have their own properties that extend these common properties. In the illustrated example, each media type rendering object is associated with a different type of media. For example, there are media-type rendering objects associated with skins, video, audio (i.e. visualizations), animations, and HTML to name just a few. Each media-type rendering object is programmed to render its associated media type. Some media type rendering objects can also host other rendering objects so that the media associated with the hosted rendering object can be rendered inside a UI provided by the host. Step 704 receives a media type for rendering. This step can be performed by a media player application. The media type can be received from a streaming source such as over a network, or can comprise a media file that is retrieved, for example, off of the client hard drive. Once the media type is received, step 706 ascertains an associated media type rendering object. In the illustrated example, this step can be implemented by having the media player application call the base rendering object with the media type, whereupon the base rendering object can ascertain the associated media type rendering object. Step 708 then calls the associated media-type rendering object and step 710 instructs the media-type rendering object to render media in the unified rendering area. In the illustrated and described embodiment, these steps are implemented by the base rendering object. Step 712 then renders the media type in the unified rendering area using the media type rendering object. The above-describe object model and method permit multiple different media types to be associated with a common rendering area inside of which all associated media can be rendered. The user interface that is provided by the object model can overcome problems associated with prior art user interfaces by presenting a unified, organized and highly integrated user experience regardless of the type of media that is being rendered. Visualizations As noted above, particularly with respect to FIG. 6 and the associated description, one aspect of the media player provides so-called “visualizations.” In the FIG. 6 example, visualizations are provided, at least in part, by the audio rendering object 608, also referred to herein as the “VisHost.” The embodiments described below accurately synchronize a visual representation (i.e. visualization) with an audio waveform that is currently playing on a client computer's speaker. FIG. 8 shows one embodiment of a system configured to accurately synchronize a visual representation with an audio waveform generally at 800. System 800 comprises one or more audio sources 802 that provide the audio waveform. The audio sources provide the audio waveform in the form of samples. Any suitable audio source can be employed such as a streaming source or an audio file. In addition, different types of audio samples can be provided from relatively simple 8-bit samples, to somewhat more complex 16-bit samples and the like. An audio sample preprocessor 804 is provided and performs some different functions. An exemplary audio sample preprocessor is shown in more detail in FIG. 9. Referring both to FIGS. 8 and 9, as the audio samples stream into the preprocessor 804, it builds and maintains a collection of data structures indicated generally at 806. Each audio sample that is to be played by the media player has an associated data structure that contains data that characterizes the audio sample. These data structures are indicated at 806a, 806b, and 806c. The characterizing data is later used to render a visualization that is synchronized with the audio sample when the audio sample is rendered. The preprocessor comprises a timestamp module 900 (FIG. 9) that provides a timestamp for each audio sample. The timestamps for each audio sample are maintained in a sample's data structure (FIG. 9). The timestamp is assigned by the timestamp module to the audio sample based on when the audio sample is calculated to be rendered by the media player. As an aside, timestamps are assigned based on the current rendering time and a consideration of how many additional samples are in the pipeline scheduled for playing. Based on these parameters, a timestamp can be assigned by the timestamp module. Preprocessor 804 also preprocesses each audio sample to provide characterizing data that is to be subsequently used to create a visualization that is associated with each audio sample. In one embodiment, the preprocessor 804 comprises a spectrum analyzer module 902 (FIG. 9) that uses a Fast Fourier Transform (FFT) to convert the audio samples from the time domain to the frequency domain. The FFT breaks the audio samples down into a set of 1024 frequency values or, as termed in this document, “frequency data.” The frequency data for each audio sample is then maintained in the audio sample's data structure. In addition to maintaining the frequency data, the preprocessor 804 can include a waveform analysis module 904 that analyzes the audio sample to provide waveform data. The preprocessor 804 can also includes a stream state module 906 that provides data associated with the state of the audio stream (i.e. paused, stopped, playing, and the like). Referring specifically to FIG. 8, a buffer 808 can be provided to buffer the audio samples in a manner that will be known and appreciated by those of skill in the art. A renderer 810 is provided and represents the component or components that are responsible for actually rendering the audio samples. The renderer can include software as well as hardware, i.e. an audio card. FIG. 8 also shows audio rendering object or VisHost 608. Associated with the audio rendering object are various so-called effects. In the illustrated example, the effects include a dot plane effect, a bar effect, and a ambience effect. The effects are essentially software code that plugs into the audio rendering object 608. Typically, such effects can be provided by third parties that can program various creative visualizations. The effects are responsible for creating a visualization in the unified rendering area 406. In the illustrated and described embodiment, the audio rendering object operates in the following way to ensure that any visualizations that are rendered in unified rendering area 406 are synchronized to the audio sample that is currently being rendered by renderer 810. The audio rendering object has an associated target frame rate that essentially defines how frequently the unified rendering area is drawn, redrawn or painted. As an example, a target frame rate might be 30 frames per second. Accordingly, 30 times per second, the audio rendering object issues what is known as an invalidation call to whatever object is hosting it. The invalidation call essentially notifies the host that it is to call the audio rendering object with a Draw or Paint command instructing the rendering object 608 to render whatever visualization is to be rendered in the unified rendering area 406. When the audio rendering object 608 receives the Draw or Paint command, it then takes steps to ascertain the preprocessed data that is associated with the currently playing audio sample. Once the audio rendering object has ascertained this preprocessed data, it can issue a call to the appropriate effect, say for example, the dot plane effect, and provide this preprocessed data to the dot plane effect in the form of a parameter that can then be used to render the visualization. As a specific example of how this can take place, consider the following. When the audio rendering object receives its Draw or Paint call, it calls the audio sample preprocessor 804 to query the preprocessor for data, i.e. frequency data or waveform data associated with the currently playing audio sample. To ascertain what data it should send the audio rendering object 608, the audio sample preprocessor performs a couple of steps. First, it queries the renderer 810 to ascertain the time that is associated with the audio sample that is currently playing. Once the audio sample preprocessor ascertains this time, it searches through the various data structures associated with each of the audio samples to find the data structure with the timestamp nearest the time associated with the currently-playing audio sample. Having located the appropriate data structure, the audio sample preprocessor 804 provides the frequency data and any other data that might be needed to render a visualization to the audio rendering object 608. The audio rendering object then calls the appropriate effect with the frequency data and an area to which it should render (i.e. the unified rendering area 406) and instructs the effect to render in this area. The effect then takes the data that it is provided, incorporates the data into the effect that it is going to render, and renders the appropriate visualization in the given rendering area. Exemplary Visualization Methods FIG. 10 is a flow diagram that describes steps in a method in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware or combination thereof. In the illustrated and described embodiment, the method is implemented in software. One exemplary software system that is capable of implementing the method about to be described is shown and described with respect to FIG. 8. It is to be appreciated and understood that FIG. 8 constitutes but one exemplary software system that can be utilized to implement the method about to be described. Step 1000 receives multiple audio samples. These samples are typically received into an audio sample pipeline that is configured to provide the samples to a renderer that renders the audio samples so a user can listen to them. Step 1002 preprocesses the audio samples to provide characterizing data for each sample. Any suitable characterizing data can be provided. One desirable feature of the characterizing data is that it provides some measure from which a visualization can be rendered. In the above example, this measure was provided in the form of frequency data or wave data. The frequency data was specifically derived using a Fast Fourier Transform. It should be appreciated and understood that characterizing data other than that which is considered “frequency data”, or that which is specifically derived using a Fast Fourier Transform, can be utilized. Step 1004 determines when an audio sample is being rendered. This step can be implemented in any suitable way. In the above example, the audio renderer is called to ascertain the time associated with the currently-playing sample. This step can be implemented in other ways as well. For example, the audio renderer can periodically or continuously make appropriate calls to notify interested objects of the time associated with the currently-playing sample. Step 1006 then uses the rendered audio sample's characterizing data to provide a visualization. This step is executed in a manner such that it is perceived by the user as occurring simultaneously with the audio rendering that is taking place. This step can be implemented in any suitable way. In the above example, each audio sample's timestamp is used as an index of sorts. The characterizing data for each audio sample is accessed by ascertaining a time associated with the currently-playing audio sample, and then using the current time as an index into a collection of data structures. Each data structure contains characterizing data for a particular audio sample. Upon finding a data structure with a matching (or comparatively close) timestamp, the characterizing data for the associated data structure can then be used provide a rendered visualization. It is to be appreciated that other indexing schemes can be utilized to ensure that the appropriate characterizing data is used to render a visualization when its associated audio sample is being rendered. FIG. 11 is a flow diagram that describes steps in a method in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware or combination thereof. In the illustrated and described embodiment, the method is implemented in software. In particular, the method about to be described is implemented by the system of FIG. 8. To assist the reader, the method has been broken into two portions to include steps that are implemented by audio rendering object 608 and steps that are implemented by audio sample preprocessor 804. Step 1100 issues an invalidation call as described above. Responsive to issuing the invalidation call, step 1102 receives a Paint or Draw call from what ever object is hosting the audio rendering object. Step 1104 then calls, responsive to receiving the Paint or Draw call, the audio sample preprocessor and queries the preprocessor for data characterizing the audio sample that is currently being played. Step 1106 receives the call from the audio rendering object and responsive thereto, queries the audio renders for a time associated with the currently playing audio sample. The audio sample preprocessor then receives the current time and step 1108 searches various data structures associated with the audio samples to find a data structure with an associated timestamp. In the illustrated and described embodiment, this step looks for a data structure having timestamp nearest the time associated with the currently-playing audio sample. Once a data structure is found, step 1110 calls the audio rendering object with characterizing data associated with the corresponding audio sample's data structure. Recall that the data structure can also maintain this characterizing data. Step 1112 receives the call from the audio sample preprocessor. This call includes, as parameters, the characterizing data for the associated audio sample. Step 1114 then calls an associated effect and provides the characterizing data to the effect for rendering. Once the effect has the associated characterizing data, it can render the associated visualization. This process is repeated multiple times per second at an associated frame rate. The result is that a visualization is rendered and synchronized with the audio samples that are currently being played. Throttling There are instances when visualizations can become computationally expensive to render. Specifically, generating individual frames of some visualizations at a defined frame rate can take more processor cycles than is desirable. This can have adverse effects on the media player application that is executing (as well as other applications) because less processor cycles are left over for it (them) to accomplish other tasks. Accordingly, in one embodiment, the media player application is configured to monitor the visualization process and adjust the rendering process if it appears that the rendering process is taking too much time. FIG. 12 is a flow diagram that describes a visualization monitoring process in accordance with one embodiment. The method can be implemented in any suitable hardware, software, firmware or combination thereof. In the illustrated example, the method is implemented in software. One embodiment of such software can be a media player application that is executing on a client computer. Step 1200 defines a frame rate at which a visualization is to be rendered. This step can be accomplished as an inherent feature of the media player application. Alternately, the frame rate can be set in some other way. For example, a software designer who designs an effect for rendering a visualization can define the frame rate at which the visualization is to be rendered. Step 1202 sets a threshold associated with the amount of time that is to be spent rendering a visualization frame. This threshold can be set by the software. As an example, consider the following. Assume that step 1200 defines a target frame rate of 30 frames per second. Assume also that step 1202 sets a threshold such that for each visualization frame, only 60% of the time can be spent in the rendering process. For purposes of this discussion and in view of the FIG. 8 example, the rendering process can be considered as starting when, for example, an effect receives a call from the audio rendering object 608 to render its visualization, and ending when the effect returns to the audio rendering object that it has completed its task. Thus, for each second that a frame can be rendered, only 600 ms can actually be spent in the rendering process. FIG. 13 diagrammatically represents a timeline in one-second increments. For each second, a corresponding threshold has been set and is indicated by the lo cross-hatching. Thus, for each second, only 60% of the second can be spent in the visualization rendering process. In this example, the threshold corresponds to 600 ms of time. Referring now to both FIGS. 12 and 13, step 1204 monitors the time associated with rendering individual visualization frames. This is diagrammatically represented by the “frame rendering times” that appear above the cross-hatched thresholds in FIG. 13. Notice that for the first frame, a little more than half of the allotted time has been used in the rendering process. For the second frame, a little less than half of the time has been used in the rendering process. For all of the illustrated frames, the rendering process has occurred within the defined threshold. The monitored rendering times can be maintained in an array for further analysis. Step 1206 determines whether any of the visualization rendering times exceed the threshold that has been set. If none of the rendering times has exceeded the defined threshold, then step 1208 continues rendering the visualization frames at the defined frame rate. In the FIG. 13 example, since all of the frame rendering times do not exceed the defined threshold, step 1208 would continue to render the visualization at the defined rate. Consider now FIG. 14. There, the rendering time associated with the first frame has run over the threshold but is still within the one-second time frame. The rendering time for the second frame, however, has taken not only the threshold time and the remainder of the one-second interval, but has extended into the one-second interval allotted for the next frame. Thus, when the effect receives a call to render the third frame of the visualization, it will still be in the process of rendering the second frame so that it is quite likely that the third frame of the visualization will not render properly. Notice also that had the effect been properly called to render the third frame (i.e. had there been no overlap with the second frame), its rendering time would have extended into the time allotted for the next-in-line frame to render. This situation can be problematic to say the least. Referring again to FIG. 12, if step 1206 determines that the threshold has been exceeded, then step 1210 modifies the frame rate to provide an effective frame rate for rendering the visualization. In the illustrated and described embodiment, this step is accomplished by adjusting the interval at which the effect is called to render the visualization. Consider, for example, FIG. 15. There, an initial call interval is represented below the illustrated time line. When the second frame is rendered, the rendering process takes too long. Thus, as noted above, step 1210 modifies the frame rate by adjusting the time (i.e. lengthening the time) between calls to the effect. Accordingly, an “adjusted call interval” is indicated directly beneath the initial call interval. Notice that the adjusted call interval is longer than the initial call interval. This helps to ensure that the effects get called when they are ready to render a visualization and not when they are in the middle of rendering a visualization frame. Notice also that step 1210 can branch back to step 1204 and continue monitoring the rendering times associated with the individual visualization frames. If the rendering times associated with the individual frames begin to fall back within the set threshold, then the method can readjust the call interval to the originally defined call interval. Conclusion The above-described methods and systems overcome problems associated with past media players in a couple of different ways. First, the user experience is enhanced through the use of a unified rendering area in which multiple different media types can be rendered. Desirably all media types that are capable of being rendered by a media player can be rendered in this rendering area. This presents the various media in a unified, integrated and organized way. Second, visualizations can be provided that more closely follow the audio content with which they should be desirably synchronized. This not only enhances the user experience, but adds value for third party visualization developers who can now develop more accurate visualizations. Although the invention has been described in language specific to structural features and/or methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or steps described. Rather, the specific features and steps are disclosed as preferred forms of implementing the claimed invention. | <SOH> BACKGROUND <EOH>Today, individuals are able to use their computers to download and play various media content. For example, many companies offer so-called media players that reside on a computer and allow a user to download and experience a variety of media content. For example, users can download media files associated with music and listen to the music via their media player. Users can also download video data and animation data and view these using their media players. One problem associated with prior art media players is they all tend to display different types of media in different ways. For example, some media players are configured to provide a “visualization” when they play audio files. A visualization is typically a piece of software that “reacts” to the audio that is being played by providing a generally changing, often artistic visual display for the user to enjoy. Visualizations are often presented, by the prior art media players, in a window that is different from the media player window or on a different portion of the user's display. This causes the user to shift their focus away from the media player and to the newly displayed window. In a similar manner, video data or video streams are often provided within yet another different window which is either an entirely new display window to which the user is “flipped”, or is a window located on a different portion of the user's display. Accordingly, these different windows in different portions of the user's display all combine for a fairly disparate and unorganized user experience. It is always desirable to improve the user's experience. In addition, there are problems associated with prior art visualizations. As an example, consider the following. One of the things that makes visualizations enjoyable and interesting for users is the extent to which they “mirror” or follow the audio being played on the media player. Past visualization technology has led to visualizations that do not mirror or follow the audio as closely as one would like. This leads to things such as a lag in what the user sees after they have heard a particular piece of audio. It would be desirable to improve upon this media player feature. Accordingly, this invention arose out of concerns associated with providing improved media players and user experiences regarding the same. | <SOH> SUMMARY <EOH>Methods and systems are described that assist media players in rendering different media types. In some embodiments, a unified rendering area is provided and managed such that multiple different media types are rendered by the media player in the same user interface area. This unified rendering area thus permits different media types to be presented to a user in an integrated and organized manner. An underlying object model promotes the unified rendering area by providing a base rendering object that has properties that are shared among the different media types. Object sub-classes are provided and are each associated with a different media type, and have properties that extend the shared properties of the base rendering object. In addition, an inventive approach to visualizations is presented that provides better synchronization between a visualization and its associated audio stream. In one embodiment, visualizations are synchronized with an audio stream using a technique that builds and maintains various data structures. Each data structure can maintain data that is associated with a particular audio sample. The maintained data can include a timestamp that is associated with a time when the audio sample is to be rendered. The maintained data can also include various characteristic data that is associated with the audio stream. When a particular audio sample is being rendered, its timestamp is used to locate a data structure having characteristic data. The characteristic data is then used in a visualization rendering process to render a visualization. | 20050124 | 20091117 | 20050825 | 99188.0 | 2 | LE, MIRANDA | METHODS AND SYSTEMS FOR SYNCHRONIZING VISUALIZATIONS WITH AUDIO STREAMS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,041,518 | ACCEPTED | Method and system for de-interlacing digital images, and computer program product therefor | A spatial-type de-interlacing process to be applied to a digital image for obtaining a spatial reconstruction. Furthermore, to the digital image there are also applied one or more temporal-type motion compensation de-interlacing processes for obtaining one or more temporal reconstructions, and the spatial reconstruction and the one or more temporal reconstructions are sent to a decision module. The decision module applies a cost function to the spatial reconstruction and the temporal reconstructions and chooses from among the spatial reconstruction and the temporal reconstructions the one that minimizes the cost function. Preferential application is to display systems, in particular displays of a cathode-ray type, liquid-crystal type, and plasma type which use a mechanism of progressive scan. | 1. A method for de-interlacing digital images, comprising: spatial de-interlacing a digital image to obtain a spatial reconstruction; applying, to said digital image, one or more de-interlacing procedures of a temporal type to obtain one or more temporal reconstructions, at least one of said one or more de-interlacing procedures including a process of motion estimation of video signals organized in successive frames divided into macroblocks, the process comprising: a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best motion vector predictor thus identified; the set of candidates formed from vectors belonging to macroblocks associated with the current vector within the current frame and the preceding frame, the refining phase comprising the operation of forming a refining grid of n points centered on the central position to which a best mode vector points; and selecting from among said spatial reconstruction and said one or more temporal reconstructions, said selecting operation including the operations of applying a cost function to said spatial reconstruction and said one or more temporal reconstructions and choosing whichever of said spatial reconstruction and temporal reconstructions minimizes said cost function. 2. The method according to claim 1 wherein said digital image includes a field to be reconstructed which includes a plurality of blocks to be reconstructed, wherein said spatial reconstruction and said one or more temporal reconstructions correspond to one of the blocks to be reconstructed and wherein the applying and selecting operations are repeated for each of the plurality of blocks to be reconstructed. 3. The method according to claim 1 wherein said cost function is a variance of said spatial reconstruction and said one or more temporal reconstructions with respect to a block to be reconstructed of the digital image. 4. The method according to claim 1 wherein said operation of choosing, from among said spatial reconstruction and said one or more temporal reconstructions, the reconstruction that minimizes said cost function is obtained by applying a median-filter function. 5. The method according to claim 1 wherein said spatial de-interlacing operation provides for operating on a work window of pixels of said digital image adjacent to a pixel to be reconstructed by performing linear interpolation on pairs of pixels belonging to said work window, and said spatial de-interlacing operation further comprises the following operations: extending the work window to a number of pairs of adjacent pixels greater than or equal to three; and adaptively sizing said work window. 6. The method according to claim 5 wherein adaptively sizing said work window includes varying in an adaptive way a number of pairs of pixels that are considered during each instance of the linear interpolation operation. 7. The method according to claim 6 wherein the adaptively varying operation comprises the steps of: using a first number of pairs of pixels for reconstructing a first pixel; and using for reconstructing a second pixel a work window that comprises a second number of pairs of pixels, the second number of pairs of pixels being determined starting from the first number of pairs of pixels according to the following criteria: if the first pixel has been reconstructed using a pair of pixels corresponding to the vertical direction, then the second number of pairs of pixels is equal to the first number of pixels minus one; if the first pixel has been reconstructed using the pair of original pixels corresponding to a steepest slope possible, then the second number of pairs of pixels is equal to the first number of pairs of pixels plus one; in all the other cases, the second number of pairs of pixels is equal to the first number; and in any case, the second number of pairs of pixels must be greater than or equal to three and smaller than or equal to a maximum number of pairs of pixels determined a priori. 8. The method according to claim 1 wherein said spatial de-interlacing further comprises operations suitable for obtaining a sub-pixel degree of precision. 9. The method according to claim 1 wherein said spatial de-interlacing comprises an operation of post-processing and final filtering of the spatial reconstruction. 10. The method according to claim 9 wherein said operation of post-processing and final filtering of the spatial reconstruction is varied dynamically according to a degree of correlation with a pixel being reconstructed. 11. The method according to claim 1 wherein said applying operation includes: reconstructing a field to be reconstructed of the digital image by dividing the field into blocks to be reconstructed, reconstructing by interpolation of blocks belonging to a preceding field and a subsequent field, and minimizing a correlation function, wherein reconstructing by interpolation includes: testing a number of motion vectors temporally and spatially preceding a current one of the blocks to be reconstructed; choosing the best mode vector from among the number of motion vectors; applying the refining grid in a neighborhood of a position pointed by the best mode vector; and choosing a best position, in one of the preceding and subsequent fields, corresponding to the current block based on the operation of applying the refining grid. 12. The method according to claim 11 wherein said one or more temporal de-interlacing procedures comprise a procedure of non-balanced estimation, which moreover comprises the operations of: generating, during said testing operation, a first vector that points to the preceding field and a second vector that points to the subsequent field with respect to the field to be reconstructed of the digital image; and obtaining said first vector and said second vector by applying, during said operation of applying a refining grid, a first grid corresponding to the preceding field and a second grid corresponding to the subsequent field. 13. The method according to claim 11, said one or more temporal de-interlacing procedures comprising a procedure of unidirectional estimation, which further comprises the operation of reconstructing the current block starting from just one of the preceding and subsequent fields by performing said operations of testing and of applying a grid on a block belonging to the one of the preceding and subsequent fields, and on a block belonging to a field of parity opposite to the field to be reconstructed. 14. A process for motion estimation in video signals organized in successive frames divided into macroblocks, the process comprising: a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best motion vector predictor thus identified; the set of candidates formed from vectors belonging to macroblocks associated with the current motion vector within a current frame and a preceding frame, the refining phase comprising the operation of forming a grid of n points centered on the central position to which a best mode vector points. 15. The process of claim 14 wherein the set includes, in the preceding frame, the vector homologous to the said current motion vector. 16. The process of claim 14, compromising the operation of scanning the macroblocks in lexicographic order within each frame, as a result of which the set includes, within the current frame, vectors belonging to macroblocks located above and to the left of the current macroblock. 17. The process of claim 14 wherein the set includes vectors belonging to at least one of the macroblocks chosen from the group consisting of: in the current frame, macroblocks located to the left of and above the current macroblock, and in the preceding frame, the homologous macroblock and the macroblocks located to the left of the current macroblock. 18. The process of claim 14 wherein the best predictor is identified, within the set, as the predictor that minimizes a residual error measurement function. 19. The process of claim 18 wherein the function is the SAD function. 20. The process of claim 18 wherein the function is the SSD function. 21. The process of claim 14 wherein the distance of the points of the grid from the center are defined as a linear function of a matching error defined in the first identification phase 22. The process of claim 14 wherein the distance is defined as the product of a coefficient and the error function. 23. The process of claim 14 wherein the error function is the SAD function. 24. The process of claim 14, comprising the operation of selecting as the motion vector for the current macroblock, within the said grid, the motion vector that minimizes a further residual error function. 25. The process of claim 24 wherein the further residual error function is the SAD function. 26. The process of claim 14, comprising the operation of selectively amplifying the grid by a given amplification factor. 27. The process of claim 26, comprising the operation of monitoring the quality of the predictor as a function of a given error function, and wherein the grid is amplified when the predictor has an error function greater than the given value. 28. The process of claim 27 wherein the grid amplification factor is calculated as a function of the analysis of the distribution of the error function for some sample sequences. 29. The process of claim 14, applied to the IPB operating mode of the H.263+video standard for the processing of pairs of PB frames, comprising the operation of selecting the temporal predictors of the B frame of a BP pair before the temporal predictors of the P frame of the BP pair. 30. The process of claim 14, applied to the APM operating mode of the H.263+ video standard, in which the frame of a macroblock is associated with a plurality of vectors, preferably four in number, associated with a corresponding plurality of further blocks constituting the macroblock to which the previously found motion vector points, in which the first identification phase is applied to the macroblock, while the second phase is applied to the blocks of the plurality to identify the plurality of vectors. 31. A motion estimation circuit for video signals organized in successive frames divided into macroblocks by means of the identification of motion vectors, the system comprising: a motion estimation block configured to implement a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best predictor thus identified; the said set of candidates being formed from vectors belonging to macroblocks close to the current vector within the current frame and the preceding frame, the estimation block configured to implement the refining phase by forming a grid of n points centered on the central position to which the best mode vector points. 32. The circuit of claim 31 wherein the estimation block is configured to include in the set in the preceding frame the vector homologous to the current motion vector. 33. The circuit of claim 31 wherein the motion estimation block is configured to scan the macroblocks in lexicographic order within each frame, as a result of which the set includes, within the current frame, vectors belonging to macroblocks located above and to the left of the current macroblock. 34. The circuit of claim 31 wherein the estimation block includes in the set vectors belonging to at least one of the macroblocks chosen from the group comprising: in the current frame, macroblocks located to the left of and above the current macroblock, and in the preceding frame, the homologous macroblock and the macroblocks located to the left of the current macroblock. 35. The circuit of claim 31 wherein the estimation block selects the best predictor, within the set, as the predictor that minimizes a residual error measurement function. 36. The circuit of claim 35 wherein the function is the SAD function. 37. The circuit of claim 35 wherein the function is the SSD function. 38. The circuit of claim 31 wherein the distance of the points of the grid from the center defined as the function, preferably linear, of the matching error defined in the first identification phase. 39. The circuit of claim 31 wherein the distance is defined as the product of a coefficient and the error function. 40. The circuit of claim 31 wherein the error function is the SAD function. 41. The circuit of claim 31 wherein the estimation block selects, as the motion vector for the current macroblock, within the grid, the vector that minimizes a further residual error function. 42. The circuit of claim 31 wherein the estimation block is capable of selectively amplifying the grid by a given amplification factor. 43. The circuit according to claim 42 wherein the estimation block monitors the quality of the predictor as a function of a given error function, and amplifies the grid when the predictor has an error function greater than the given value. 44. The circuit of claim 42 wherein the estimation block calculates the grid amplification factor as a function of the analysis of the distribution of the error function for some sample sequences. 45. The circuit of claim 31, configured to operate according to the IPB operating mode of the H.263+ video standard for the processing of pairs of PB frames, in which the estimation block selects the temporal predictors of the B frame of a BP pair before the temporal predictors of the P frame of the BP pair. 46. The circuit of claim 31, configured to operate according to the APM operating mode of the H.263+ video standard, in which the estimation block associates the frame of a macroblock with a plurality of vectors, preferably four in number, associated with a corresponding plurality of further blocks constituting the macroblock to which the previously found motion vector points, in which the estimation block applies, respectively, the first identification phase to the macroblock, and the second phase to the blocks of the plurality to identify the plurality of vectors. 47. A computer product directly loadable into a memory of a digital computer and comprising software code portions for performing, when the product is run on a computer, the following operations: spatial de-interlacing a digital image to obtain a spatial reconstruction; at least one or more de-interlacing procedures including a process motion estimation of video signals organized in successive frames divided into macroblocks, the process comprising: a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best motion vector predictor thus identified; the set of candidates formed from vectors belonging to macroblocks association with the current vector within the current frame and the preceding frame, the refining phase comprising the operation of forming a grid of n points centered on the central position to which a best mode vector points; and selecting from among said spatial reconstruction and said one or more temporal reconstructions, said selecting operation including the operations of applying a cost function to said spatial reconstruction and said one or more temporal reconstructions and choosing whichever of said spatial reconstruction and temporal reconstructions minimizes said cost function. 48. A method for de-interlacing a digital image that includes interlaced first and second fields, the first field including first and second blocks of pixels, comprising: spatial de-interlacing the first block to obtain a spatial reconstruction; temporal de-interlacing the second block to obtain a temporal reconstruction, the temporal de-interlacing including: testing a number of motion vectors temporally and spatially preceding a current one of the blocks to be reconstructed; choosing a best vector from among the number of motion vectors; applying a refining grid in a neighborhood of a position pointed by the best vector; choosing a best position, in one of the preceding and subsequent fields, corresponding to the current block based on the operation of applying the refining grid; and creating the temporal reconstruction by interpolating a block that includes the best position; and constructing a reconstructed image by combining the spatial reconstruction and temporal reconstruction with the second field. 49. The method of claim 48, further comprising: temporal de-interlacing the first block to obtain a temporal reconstruction of the first block; and determining which of the spatial reconstruction and the temporal reconstruction of the first block minimizes a cost function, wherein the construction step combines the second field with whichever of the spatial reconstruction and the temporal reconstruction of the first block minimizes the cost function. 50. The method of claim 48 wherein the spatial de-interlacing step includes, for each pixel of the first block: constructing a work window that includes pixels of the second field adjacent to the pixel of the first block, and intermediate pixels created based on a plurality of the pixels of the second field adjacent to the pixel of the first block; and creating for the spatial reconstruction a reconstructed pixel corresponding to the pixel of the first block by performing linear interpolation on pairs of pixels of the work window. 51. The method of claim 50 wherein the first block includes first and second pixels and the spatial de-interlacing step includes adaptively sizing the work window constructed for the second pixel based on the creating step performed for the first pixel. 52. The method of claim 51 wherein the work window constructed for the first pixel includes a first number of pairs of pixels and adaptively sizing the work window constructed for the second pixel includes: using a second number of pairs of pixels for the work window of the second pixel, equal to the first number of pixels minus one, if the first pixel has been reconstructed using a pair of pixels corresponding to a vertical direction; using a third number of pairs of pixels for the work window of the second pixel, equal to the first number of pairs of pixels plus one, if the first pixel has been reconstructed using a pair of pixels corresponding to a steepest slope possible; using the first number of pairs of pixels for the work window of the second pixel in other cases. 53. The method of claim 48 wherein the temporal reconstruction step includes non-balanced estimation, which includes: generating a first vector that points to a first pixel in a preceding field and a second vector that points to a second pixel in a subsequent field with respect to the first field; creating a first refining grid of pixels that includes the first pixel and a second refining grid of pixels that includes the second pixel; determining a third vector that points to one of the pixels in the first refining grid and a fourth vector that points to one of the pixels in the second refining grid; and creating the temporal reconstruction by interpolating a first block that includes the pixel pointed to by the third vector and second block that includes the pixel pointed to by the fourth vector. 54. The method of claim 48 wherein the temporal reconstruction step includes unidirectional estimation, which includes reconstructing the first block starting from a block corresponding to the first block in the second field and from just one of a preceding field and a subsequent field. 55. A process for motion estimation in video signals organized in successive frames divided into macroblocks by means of the identification of motion vectors, the process comprising a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best predictor thus identified; the said set of candidates being formed from vectors belonging to macroblocks close to the said current vector within the current frame and the preceding frame. 56. The process according to claim 55, characterized in that the said set includes, in the preceding frame, the vector homologous to the said current motion vector. 57. The process according to claim 55, characterized in that it comprises the operation of scanning the said macroblocks in lexicographic order within each frame, as a result of which the said set includes, within the current frame, vectors belonging to macroblocks located above and to the left of the current macroblock. 58. The process according to claim 55, characterized in that the said set includes vectors belonging to at least one of the macroblocks chosen from the group consisting of: in the current frame, macroblocks located to the left of and above the current macroblock; and in the preceding frame, the homologous macroblock and the macroblocks located to the left of the current macroblock. 59. The process according to claim 55, characterized in that the said best predictor is identified, within the said set, as the predictor which minimizes a residual error measurement function. 60. The process according to claim 59, characterized in that the said function is the SAD (sum of absolute differences) function. 61. The process according to claim 59, characterized in that the said function is the SSD (sum of squared differences) function. 62. A system for motion estimation in video signals organized in successive frames divided into macroblocks by means of the identification of motion vectors, the system comprising a motion estimation block configured to implement a first identification phase in which, starting from a current motion vector, a best motion vector predictor is identified within a set of candidates, and a second phase of refining the best predictor thus identified; the said set of candidates being formed from vectors belonging to macroblocks close to the said current vector within the current frame and the preceding frame. 63. The system according to claim 62, characterized in that the said estimation block is configured to include in the said set, in the preceding frame, the vector homologous to the said current motion vector. 64. The system according to claim 62, characterized in that it comprises the operation of scanning the said macroblocks in lexicographic order within each frame, as a result of which the said set includes, within the current frame, vectors belonging to macroblocks located above and to the left of the current macroblock. 65. The system according to claim 62, characterized in that the said estimation block includes in the said set vectors belonging to at least one of the macroblocks chosen from the group consisting of: in the current frame, macroblocks located to the left of and above the current macroblock; and in the preceding frame, the homologous macroblock and the macroblocks located to the left of the current macroblock. 66. The system according to claim 62, characterized in that the said estimation block selects the said best predictor, within the said set, as the predictor which minimizes a residual error measurement function. 67. The system according to claim 66, characterized in that the said function is the SAD (sum of absolute differences) function. 68. The system according to claim 66, characterized in that the said function is the SSD (sum of squared differences) function. | BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to techniques for digital-image processing, including motion estimation techniques, and has been developed with particular attention paid to its possible application to the processing of television images and to the display of the television signal on displays, such as personal-computer displays of the cathode-ray type, liquid-crystal type or plasma type, which use a progressive-scanning mechanism. Even though in what follows, for reasons of clarity and simplicity of exposition, practically exclusive reference will be made to this application, it must in any case be borne in mind that the significance of application of the invention is more general. The invention is in fact applicable to all techniques of digital-image processing in which there arise operating conditions of the type described in what follows. 2. Description of the Related Art The television system adopted in Europe, i.e., the Phase-Alternate-Line (PAL) system, is characterized by a frame frequency of 25 Hz: this means that it is possible to display 25 images or frames per second, each of which is made up of a grid of 720×576 samples, called pixels (picture elements), arranged in rows. In fact, the raster, i.e., the electron beam that draws the image on the television display, operates at a frequency of 50 Hz, and once every second creates on the display 50 half-images, or fields, each of which is sampled at a different instant in time, with a time interval between said fields of one fiftieth of a second. Each field contains alternately the even rows only or else the odd rows only of a complete image. Consequently, the images displayed on the television screen have their even rows belonging to one field, referred to as even field, and their odd rows belonging to another field, referred to as odd field. When the images are divided in this way, they are referred to as “interlaced” images. The PAL system was originally conceived for systems with cathode-ray displays, but television images are not suited for being displayed on other types of display, such as, for example, computer monitors, or modern televisions with plasma or liquid-crystal displays. These systems, in fact, use a display mechanism referred to as “progressive”, which each time composes on the display a complete image, and not a single field. A television video sequence in PAL format, displayed on these systems, would cause an unpleasant “mosaic” effect, due to the fact that each image is in effect made up of two different interlaced fields. To display the images correctly, it is therefore necessary to subject them to a de-interlacing procedure, which provides for reconstruction of a complete image, starting from a single field. In the case of even fields, the odd lines of the image are reconstructed; in the case of odd fields, the even lines of the image are reconstructed. The reconstructed lines are then added to the original ones, and a complete image or frame is thus obtained. The de-interlacing procedure can be carried out in different ways, which can be reduced to two main categories: motion-compensated procedures; and non-motion-compensated procedures. Motion-compensated (or temporal) de-interlacing procedures use motion-estimation techniques for reconstructing a field starting from temporally preceding and subsequent information, whilst non-motion-compensated (or spatial) de-interlacing procedures use spatial interpolation for reconstructing the even or odd rows of a frame, starting from the odd or even rows, respectively. To carry out the procedure of non-motion-compensated de-interlacing of digital images, it is known to use a procedure referred to as Edge-Line Averaging (ELA). FIG. 1 illustrates a part of the pixels of an image or frame FRM. In this frame FRM, the odd rows that make up a field to be reconstructed MFD are to be reconstructed starting from the even rows. According to the ELA procedure, the pixels belonging to row N, where N is an odd integer, can be reconstructed starting from the adjacent pixels, belonging to the rows N−1 and N+1. In particular, if a pixel to be reconstructed X of the field MFD is in the position M on the row N of the frame FRM, it can be reconstructed using the pixels in the positions M−1, M and M+1 on the aforesaid rows. If A, B and C designate the pixels belonging to a work window FL in positions M−1, M and M+1 in the row N−1 of the frame FRM, and D, E and F designate the pixels in positions M−1, M and M+1 in the row N+1 of the frame FRM, the pixel to be reconstructed X can be reconstructed using the following interpolation formula: X = { A + F 2 if A - F < B - E , C - D B + E 2 if B - E < A - F , C - D C + D 2 if C - D < A - F , B - E ( 1 ) In other words, as can also be inferred from FIG. 1, the pixel X to be reconstructed is reconstructed by linear interpolation of the most correlated pair of pixels belonging to the nearest rows of the field of opposite parity, the correlation between two pixels being defined as the distance of the respective values. To carry out, instead, the procedure of motion-compensated, or temporal, de-interlacing of digital images for composing the field to be reconstructed MFD, illustrated in FIG. 2, this field to be reconstructed MFD is, instead, broken down into a series of blocks BK. Each block BK is reconstructed by interpolation of two blocks BKm, BKn belonging to another two frames, of the same parity, that temporally precede and follow, respectively, the frame to be reconstructed containing the field to be reconstructed MFD. The preceding frame includes a field n that contains the block BKn and the following frame includes a field m that contains the block BKm. The pair of blocks is chosen by minimizing a correlation function, such as, for example, the Sum-of-Absolute-Differences (SAD) function, which is defined as follows: if SAD(x,y) is the SAD function between a preceding block BKn of W×H pixels (where W and H are positive integers), set in a position (x,y) in the preceding field n, which has pixels of intensity Vn(x+i,y+j), and a corresponding subsequent block BKm, set in a position (x+dx,y+dy) in the subsequent field m, which has pixels of intensity Vm(x+dx+i,y+dy+j), then the SAD function is: SAD ( xy ) = ∑ i = 0 W ∑ j = 0 H V n ( x + i , y + j ) - V m ( x + dx + i , y + dy + j ) ( 2 ) The position of the preceding reference block BKn with respect to the block BK to be reconstructed is indicated by a motion vector MV, whilst the position of the subsequent block BKm is indicated by an equal and opposite motion vector designated by −MV in FIG. 2. In this case, the term “balanced motion estimation” is used, in so far as the two reference blocks, the preceding one BKn and the subsequent one BKm, are in an opposite position with respect to that of the block BK to be reconstructed. For minimizing the correlation function, whether it is the aforesaid SAD function or any other function, it is possible to use any technique of motion estimation, such as for example the full-search technique, which verifies exhaustively all the possibilities within a certain search area, called “search window”. The de-interlacing procedures listed above, however, do not succeed in guaranteeing optimal performance in all the situations that can occur during processing of a video sequence. BRIEF SUMMARY OF THE INVENTION One embodiment of the present invention provides a solution that guarantees optimal performance in the operations of de-interlacing of an interlaced digital image. According to the present invention, one embodiment is directed to a method, another to the corresponding system, and yet another to the corresponding computer product directly loadable into the memory of a digital computer such as a processor. Basically, the solution described herein provides for making a choice between different procedures for de-interlacing digital images that generate different reconstructions, by an operation of evaluation and minimization of a cost function. There are also proposed improved procedures of digital image de-interlacing of a spatial and temporal type. As compared to the known solutions, a solution proposed herein enables a reconstruction to be obtained without appreciable visual defects. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The invention will now be described, purely by way of non-limiting example, with reference to the annexed drawings, in which: FIG. 1 and FIG. 2, which correspond to the known art, have already been described previously; FIG. 3 illustrates a diagram corresponding to an operation of a procedure of spatial de-interlacing comprised in one method according to the invention; FIG. 4 shows the criteria for the execution of the spatial and temporal correlation function on macroblocks according to one embodiment of the invention; FIG. 5 shows the execution of the refining function as part of the solution according to the invention; FIGS. 6 and 7 show schematically the application of the invention to the H.263+ video standard; FIG. 8 illustrates a diagram corresponding to an operation of a procedure of temporal de-interlacing comprised in the method of FIG. 3; FIG. 9 illustrates a diagram corresponding to an operation of a procedure of temporal de-interlacing comprised in the method of FIG. 3; FIG. 10 illustrates a schematic circuit diagram of a de-interlacing system implementing the method of FIG. 3; and FIG. 11 is a diagram of a computer system that can be used to implement the present invention. DETAILED DESCRIPTION OF THE INVENTION The de-interlacing procedure proposed provides basically for providing a non-motion-compensated (or spatial) de-interlacing procedure as well as a motion-compensated (or temporal) de-interlacing procedure designed to produce reconstructions of improved quality, as well as making a decision among the reconstructions originated by said spatial and temporal procedures, introducing an appropriate cost function for making this decision. There is thus described hereinafter, first of all, a non-motion-compensated digital-image de-interlacing procedure which improves the non-motion-compensated procedure for de-interlacing digital images of the ELA type described previously with reference to FIG. 1 by introducing the following operations: an operation of extension of the work window; operations designed to obtain a sub-pixel degree of precision; an operation of adaptive sizing of the work window; and an operation of post-processing and final filtering of the spatial reconstruction. These operations are now described in greater detail, with reference to FIG. 3. As regards the operation of extension of the work window FL, the spatial de-interlacing procedure proposed does not envisage simply considering just three pairs of pixels (as described previously with reference to FIG. 1) among which the most correlated pair is to be chosen, but rather it envisages the use of a number of pairs P of pixels greater than or equal to three. The advantage that is obtained extending in this way the work window FL from the immediately adjacent pixel to other nearby pixels is an increase in the likelihood of finding a best correlation, the result being that the reconstructed pixel will be more similar to the adjacent ones, and the overall quality of the final image will thus be improved. The contribution of the operation of extension of the work window FL described above can be evaluated in association with the operation of adaptive sizing of the work window FL, which will be described in what follows. The procedure of non-motion-compensated de-interlacing of digital images of the ELA type described above with reference to FIG. 1 considers only the original pixels that are in the row above and in the row below the one containing the pixel X to be reconstructed. The non-motion-compensated de-interlacing procedure proposed provides for increasing the quality of the spatial reconstruction by considering, in addition to the original pixels, also the pixels in the intermediate positions, i.e., implementing operations designed to obtain a sub-pixel degree of precision. For example, in the case of a number of pairs P equal to three, it is possible to define new pixels A′, B′, D′ and E′, as shown in FIG. 3, where the pixel A′ is located between the pixel A and the pixel B, the pixel B′ between the pixel B and the pixel C, the pixel D′ between the pixel D and the pixel E, and the pixel E′ between the pixel E and the pixel F. In this case, the relation (1) for calculating the pixel X is transformed as indicated below: X = { A + F 2 if A - F < B - E , C - D , A ′ - E ′ , B ′ - D ′ A ′ + E ′ 2 if A ′ - E ′ < A - F , B - E , C - D , B ′ - D ′ B + E 2 if B - E < A - F , C - D , A ′ - E ′ , B ′ - D ′ B ′ + D ′ 2 if B ′ - D ′ < A - F , B - E , C - D , A ′ - E ′ C + D 2 if C - D < A - F , B - E , A ′ - E ′ , B ′ - D ′ ( 3 ) The new pixels A′, B′, C′ and D′ can be calculated starting from the original pixels horizontally adjacent thereto. By way of example, but not necessarily, it is possible to define the pixel A′ simply by linear interpolation: A ′ = A + B 2 ( 4 ) Once the operations described above designed to obtain a sub-pixel degree of precision have been introduced, it is possible to introduce the operation of adaptive sizing of the work window FL in the procedure of non-motion-compensated de-interlacing of digital images of the ELA type. The procedure for non-motion-compensated de-interlacing of digital images of the ELA type according to the known art identifies the pair of pixels having the maximum correlation by simply considering the distance between the values of the two pixels. Not necessarily does this procedure enable the maximum visual quality to be achieved, in so far as the pair having the maximum correlation is not always the right one to be interpolated. To overcome this drawback, there are imposed restrictions on the procedure of search for the pair having the maximum correlation among the possible pairs P of pixels. This can be obtained by adaptively varying the number of pairs P each time considered, i.e., the size of the work window FL. To provide a better example, consider a first pixel to be reconstructed X1 and a second pixel to be reconstructed X2, where the first pixel to be reconstructed X1 has already been reconstructed using a first number P1 of pairs of pixels, whilst the second pixel to be reconstructed X2 has still to be reconstructed using a work window that comprises a second number P2 of pairs of pixels; the second number P2 of pairs can then be determined starting from the first number P1 of pairs applying the following rules: if the first pixel to be reconstructed X1 has been reconstructed using the pair of original pixels corresponding to the vertical direction, then P2=P1−1; if the first pixel to be reconstructed X1 has been reconstructed using the pair of original pixels corresponding to the steepest slope possible (both towards the right and towards the left), then P2=P1+1; in all the other cases, P2=P1; in any case, it must be always P2≧3 and P2≦Pmax, where Pmax indicates a maximum number of pixels determined a priori. From the simulations carried out, it has been found experimentally that an adequate value for the maximum number of pairs of pixels Pmax is seven. A further extension of the work window would take into account pixels that are located at an excessive distance apart from one another, and hence, in effect, uncorrelated. Once an even field has been reconstructed on the basis of an odd field, or vice versa, applying the spatial de-interlacing procedure just described, it is necessary to put this even field and this odd field together to obtain the final complete image. A similar operation can be executed by simply alternating the original rows with the reconstructed ones, but this can lead to an undesirable effect of distortion, in the case where some pixels are reconstructed in an excessively approximate manner. This drawback can be overcome by carrying out an appropriate post-processing operation, i.e., a filtering operation, on each pixel to be reconstructed X, to obtain a new reconstructed pixel X′ filtered according to the original pixels A and B respectively in a top position and a bottom position with respect to the pixel to be reconstructed X, i.e., by applying a vertical FIR filter defined as: X′=f(X,A,B) (5) A possible choice for the filtered reconstructed pixel X′ can for example be the following: X ′ = A + 2 X + B 4 ( 6 ) Moreover, the filtering operation just described can be dynamically varied according to the degree of correlation of the pixel to be reconstructed X with the pixels A and B, for the purpose of obtaining the best performance possible. In other words, there can be chosen a first filtering function f1 if the relations |A−X|<T or |B−X|<T are verified, and a second filtering function f2 otherwise. T indicates an appropriate threshold value determined heuristically, and in this case equal to 15, since the values of the pixels are comprised between 0 and 255. In this case, the filtering functions f1 and f2 are determined via the following coefficients: μl=(0.125,0.75,0.125) f2=(0.25, 0.5, 0.25) The first filtering function f1 is used when the pixel to be reconstructed X is already sufficiently correlated with the two adjacent pixels, the need to increase to no purpose the correlation being thus prevented. Instead, the second filtering function f2 is used when the initial correlation is low with the aim of increasing it. Note that the choice of coefficients that are powers of ½ advantageously favors an immediate hardware implementation of the procedure. The above post-processing operation can be considered similar to the smoothing operation, commonly used in the field of digital-image processing. It is to be noted, however, that the smoothing operation is used for smoothing out the outlines of objects, when these are too evident, whilst in the context of the spatial-de-interlacing procedure proposed, the post-processing operation described above is necessary for restoring the correct outline of an object, in the case where it has been reconstructed in an approximate way. Furthermore, normally, the smoothing operation is obtained by applying a two-dimensional filter with fixed coefficients. In the case of the operation of post-processing and filtering described, instead, a one-dimensional non-linear adaptive filter, purposely designed for increasing the correlation between the pixel to be reconstructed X and the original pixels vertically adjacent thereto. Finally, application to the spatial-de-interlacing procedure of a simple conventional smoothing operation would cause an increase of the sawtoothing of the inclined edges, which is aesthetically undesirable, said increase being due to the alternation of the original rows and the rows reconstructed in such a way as to resemble excessively the original ones. Hence, at the expense of just a minimal increase in computational complexity, the procedure of non-motion-compensated, or spatial, digital-image de-interlacing proposed enables a sensible improvement to be achieved as compared to the known methods, both in terms of PSNR (Peak Signal-to-Noise Ratio) obtained and in qualitative terms, i.e., by direct observation of the video sequences on television sets of professional quality. The de-interlacing procedure moreover exploits an improved temporal de-interlacing procedure, in which the motion-estimation de-interlacing technique is extended and modified with respect to the motion-estimation procedure for video compression described in the European patent application EP-A-1152621, which corresponds to U.S. patent application Ser. No. 09/849,503, which was published on Jan. 31, 2002 as U.S. Publication No. US-2002-0012396A1, all of which are incorporated herein by reference in their entireties. The above motion-estimation procedure for video compression is designed to operate in association with low-complexity video-compression systems, such as for example the H.263 or H.263+ coding systems. In these systems, motion estimation is used to predict a macroblock of 16×16 pixels belonging to the current image, with respect to another macroblock, called predictor, which is in an image preceding the current one. The motion-estimation procedure operates in such a way as to find the position of the predictor macroblock with respect to the current macroblock, identifying the predictor that minimizes a certain cost function, such as, for example, the SAD function defined by the relation (2) provided above. In accordance with one disclosed embodiment of the invention, the motion estimation process belongs to the category of processes based on the evaluation of the spatio-temporal correlation existing among motion vectors belonging to adjacent blocks. If the motion field varies slowly both locally and from frame to frame is true, then it may be possible to check only a few sets of candidate motion vectors. The candidate motion vector that produces the minimum SAD is selected as the predictor motion vector which, after a refining phase, yields the final motion vector. Since it provides for the use of a motion vector acting as a predictor, this solution is classed as a prediction process. Like all processes of this type, it is essentially based on two phases, namely: the identification of the candidate predictors, and the refining of the best predictor. At the end of the whole process, the motion vector that produces the lowest SAD is associated with each macroblock. The first phase mentioned above therefore consists in identifying, from a set of candidates, the predictor motion vector identified as the best and therefore as that to which the subsequent refining phase is to be applied. With the objective of achieving a low-complexity solution, the embodiment of the invention is intended to reduce the number of candidates as far as possible and, in the same way, to select “good” candidates, presumably those close to the correct vector. The criterion for constituting the set of candidates is that of selecting the vectors of the relative macroblock position, in the current frame and in the preceding frame, which is close to the current vector. Naturally, there is a constraint due to the fact that a predictor vector must be calculated in advance. Since the macroblocks are normally subjected to scanning in lexicographical order, only the vectors belonging to macroblocks located above and to the left of the current one are available as vectors usable as predictors. FIG. 4 shows a solution to reduce the number of candidates while keeping the computation cost low. In a preferred embodiment, the solution according to the invention uses—for a macroblock—four candidate predictors; more precisely, these are two spatial predictors (one to the left and one above the current macroblock) taken from the same frame, and two temporal predictors (one homologous with and one to the left of the current macroblock) in the preceding frame. This solution is shown schematically in FIG. 4, where the preceding frame (frame t-1) is shown on the left and the current frame (frame t) is shown on the right. The current macroblock is the one left blank in the right-hand part of FIG. 4 and the macroblock G in the left-hand part of FIG. 4 represents the homologous macroblock of the preceding frame. For clarity, the two spatial predictors taken from the frame t are those indicated by the letters A and B. The two temporal predictors are those indicated by the letters G and H in the frame t-1. The motion vector, of the set thus defined, which produces the lowest residual error (for example, the lowest SAD function) is used as the starting point for the subsequent refining phase and is indicated below as the “best motion vector predictor.” When the predictor in question has been determined, the process continues with a refining phase implemented by means of a grid of n points that is applied to it. An example of such a grid is shown in FIG. 5. The grid in question is formed by four points I to IV at the vertices of a square and four further points V to VIII located at the vertices of a square of smaller size with its sides inclined at 45° to the sides of the square at whose vertices the points I to IV are located. The background grid shown in FIG. 5 is a half pixel grid and it is assumed that points I to VIII are positioned at points of intersection of the lines of this grid. The aforesaid grid is considered to be centered on the position to which the best motion vector MV points. The distance of points I to VIII from the center is defined by a linear function which depends on the matching error found during the preceding step (for example, a distance defined as the product of corresponding coefficients and the corresponding SADs). Additionally, since the process operates with motion vectors with a precision of half a pixel, in a preferred embodiment, the points are at a distance of half a pixel from the center. After all the points on the grid have been considered, the vector with the lowest SAD is selected as the motion vector for the current macroblock and is used for its motion compensation. In those cases in which the best predictor may be incorrect, for example in the presence of a change of scene in the environment of a rapidly changing motion, the grid correction can be amplified. The grid is amplified only when the best predictor has a high SAD, which means that it is probably not a good predictor. Starting from the analysis of the SAD distributions found for some sample sequences, it is possible to determine a linear function of the SAD (for example, the same coefficient x SAD function mentioned above), which can be used to calculate the magnitude of the amplification function and the number of points, while also discriminating the conditions in which amplification is necessary from those in which this step is not necessary. A measure of the complexity of the solution according to the invention (particularly in respect of the comparison with other known solutions, such as those based on a full search algorithm) is provided by the number of times that the cost function is calculated. In the case in question, the measure can be found in the number of operations of calculating the SAD function per macroblock. It should be noted that this measure of complexity is completely independent of the format and frame frequency of the sequence on which the coding process is carried out, and is therefore valid for all the coding algorithms. For a full search algorithm, the number of calculations of the SAD depends on the dimensions of the search area. For example, in the default prediction operating mode of the H.263+video standard (see the document Image Processing Lab, University of British Columbia, “TMN (H.263+) encoder/decoder, version 3.0,” TMN (H.263+) codec, September 1997) the search area has a size of 32×32 pixels. Additionally, the best motion vector that is found is refined with a precision of half a pixel, by the application of a grid on n points. Therefore, the computational complexity of the full search algorithm is OPMB=Num.SADinteger-pixel+Num.SADhalf-pixel=32×32+8=1032 (II) However, the embodiment of the invention requires, in the example of embodiment illustrated here, four calculations of SAD for the selection of the best predictor (see FIG. 4) and eight calculations for the refining grid (see FIG. 5). The calculation of the SAD function for the null vector must be added to these calculations. In conclusion, the total number of calculations of the SAD function is given, in the solution according to the invention, by: OPMB=Num.SADhalf-pixe+Num.SADNull-Vector=12+1=13 (III) This embodiment of the invention can therefore be used to reduce the computational cost by approximately 90% with respect to the full search algorithm. Moreover, the cost is stable because the total number of calculations of the SAD function is the same for each macroblock. This gives rise to a considerable advantage of the solution according to the invention over other motion estimation algorithms with variable complexity deriving from their interactive form. The embodiment of the invention lends itself to particularly advantageous developments with reference to the H.263+ video standard mentioned above. This standard provides some optional modes which can be used to improve the subjective quality of the reconstructed sequences. In general, however, the use of these modes produces a more or less significant increase in the computational cost. In the context of the illustration of the present invention it is advantageous to consider, among these options included in the standard, some options which are closer to the problem of motion estimation, in other words the improved PB-frames mode, abbreviated to “IPB mode,” and the advanced prediction mode (commonly abbreviated to “APM”). The integration of these options into a predictive algorithm makes them more uniform with the standard. For a description of the IPB mode, reference may usefully be made to the documents ITU Telecom Standardization Sector of ITU, “Video Coding for Low Bitrate Communication,” Draft 21 ITU-T, Recommendation H.263+Version 2, January 1998 and ITU Telecom Standardization Sector of ITU, “Video Codec Test Model, Near Term, Version 10,” TMN10 ITU-T, April 1998, as well as to the general document on the H.263+standard cited previously, which are incorporated herein by reference in their entirety. As a variation from the standard, it is possible to introduce one change only in order to permit its integration in a functional way into the algorithm. This change relates to the order in which the motion estimation is carried out. The standard applies the motion estimation on the P frame of the PB pair first and then on the B frame of the pair (even if the temporal order is exactly the reverse). However, this solution has the drawback that the temporal predictors of the B frame of the PB pair would be chosen from the reference motion field relating to the successive frame in temporal terms. In the solution shown in FIG. 6, however, it can be seen that, in a possible application of the embodiment of the invention, the estimation order is inverted to maintain the temporal continuity of the frames. In particular, FIG. 6 shows, in the context of the frame sequence in the IPB mode, the management of the first PB pair (in other words, the frames P2B2). The ITU documents cited previously provide a detailed description of the APM mode. In this field of application, the disclosed embodiment of the invention makes it possible, for example, to associate the frame of a macroblock with four vectors instead of only one. All this is done in order to provide a more accurate estimate. As indicated in the standard, the use of the APM consists in an application of the motion estimation algorithm to the current macroblock (to obtain an associated motion vector as in the base mode) and a successive application of the same algorithm for each 8×8 block forming the 16×1 6 macroblock to which the previously found vector points (so that four associated vectors are obtained for the current macroblock). By means of special preference rules, the coder chooses the optimal mode for preparing the current macroblock. In the embodiment shown schematically in FIG. 7, based on the application of the solution according to the invention, the predictive process is applied in its full version only to the search vector associated with the 16×16 macroblock. On the other hand, only the refining phase of the algorithm is applied to the search for the four vectors for the 8×8 blocks. This scheme is shown in FIG. 7, where CM indicates the current macroblock and PM indicates the macroblock found by prediction. The arrow BV indicates the obtaining of the best motion vector for the current 16×16 macroblock, implemented by means of the predictive process, while the arrows MV1, MV2, MV3 and MV4 illustrate the obtaining of four corresponding best vectors obtained by the refining phase for the corresponding four 8×8 blocks of the PM macroblock obtained by prediction. In the case of the APM mode, the complexity of the process according to the invention is greater as compared with the base version, owing to the fact that the number of predictor candidates is higher. For example, if the algorithm uses the equivalent of twenty-one predictors for a total of twenty-one SAD calculation operations per macroblock (it is emphasized that this is the maximum number of operations), the gain in terms of complexity is 1.62 times with respect to that of the base version. In the case of a temporal de-interlacing procedure, as explained previously with reference to FIG. 2, the task is different in so far as the aim is to find a pair of blocks. In this case, the motion-compensated de-interlacing procedure comprises two distinct operations: an operation of testing of a number Q of vectors temporally and spatially preceding the one referring to the current macroblock, with final choice of the best vector; and an operation of application of a refining grid, made up of R points, in the neighborhood of the position pointed by the best vector found in the preceding step. These two operations are followed by a conclusive operation of choice of the best position. In the case where it is desired to carry out a balanced estimation, the proposed procedure operates in each step in such a way as to generate a backward motion vector MV, which points to the temporally subsequent field, and a forward motion vector −MV, which is equal and opposite and points to the temporally preceding field, in a similar way to what has been illustrated previously with reference to FIG. 2; the total number of vectors tested is hence Q+R. There are, however, introduced further improvements to increase the performance of the temporal de-interlacing procedure. In the case of non-balanced estimation, there is proposed elimination of the limitation represented by balanced estimation, by operating in such a way that the procedure will generate at each step two distinct vectors, as illustrated in FIG. 8: a first backward vector MV1 that points to the preceding field n and a second forward vector MV2 that points to the subsequent field m. In this case, the second vector MV2 is in general different in value and sign from the first vector MV1. The first backward vector MV1 and the second forward vector MV2 are obtained applying two different refining grids in the operation of application of a refining grid of the temporal de-interlacing procedure proposed, a first grid referring to the preceding field and a second grid to the subsequent field. It is therefore necessary to test all the possible combinations of the R points of the first grid with the Q points of the second grid, for a total of R×Q different tests to be carried out. Since the hypothesis underlying balanced estimation is a linear movement of an object from the preceding field n to the subsequent field m with respect to the current field, the improvement just described removes said hypothesis, since it enables the movements of an object to be approximated by a broken line, thus obtaining as a final result a greater precision of the procedure. In the case of bi-directional estimation, motion estimations, whether balanced or non-balanced, identify the movement of an object which, hypothetically, shifts from the field n preceding to the field m subsequent to the field to be reconstructed MFD. It is, however, possible for an object to disappear as it passes from one field to the other, for example because it exits the display area or because there is a change of scene in the video sequence. In this case, the motion estimations described previously would fail, since they would seek a correlation that in actual fact is absent. To solve this problem, a one-directional motion estimation can be carried out, which reconstructs the current block BK starting from just the preceding field n, which is the case illustrated in FIG. 9, or else starting from just the subsequent field m. In this case, the correlation is sought between a block belonging to the preceding field n (or else the subsequent block m) and a block BKh belonging to the current field of parity opposite to that of the current field to be reconstructed. The field with opposite parity is designated by h. This block BKh is the homologue of the current block BK to be reconstructed, i.e., it has the same spatial co-ordinates within the respective field. In this case, it is assumed that the field h of parity opposite to that of the field to be reconstructed constitutes a valid approximation for minimization of the chosen cost function. The motion-compensated de-interlacing procedure proposed can operate with a high sub-sampling precision, such as, for example, a quarter or even one eighth of a pixel, given that subsampling to half a pixel does not provide a precision sufficient for carrying out high-quality de-interlacing. In this case, sub-sampling is obtained by successive approximations, i.e., by means of successive filtering steps that bring the precision from one pixel to half a pixel, and subsequently from half a pixel to a quarter of a pixel, and then (optionally) from a quarter to one eighth of a pixel. The sub-sampling operations are performed by different filters, designed for obtaining the maximum video-mage quality possible. As regards the size of the blocks, it is, in general, advisable to operate with a size of the blocks of 16×16 pixels since this is the size adopted for motion estimation by the various video-compression standards, such as H.263 and H.263+. The video-compression procedure, for example, is also suited for the APM mode of H.263+, by splitting a macroblock of 16×16 pixels into four blocks of 8×8 pixels, for each of which a distinct motion vector is generated. In the case of a temporal de-interlacing procedure, operating with a size of the blocks of 16×16 pixels does not, however, lead to obtaining a sufficient precision. Hence, the proposed procedure starts from a size of 8×8 pixels, then passes to 4×4 and 2×2 pixels, in a similar way to what has been already adopted for the H.263+ coding, i.e., applying subsequently just the refinement operation in order to identify the four 4×4 vectors starting from the individual 8×8 vector, and subsequently four 2×2 vectors starting from each individual 4×4 vector. The motion-compensated de-interlacing procedure just described enables a considerable improvement to be achieved as compared to the known methods, both in terms of Peak Signal-to-Noise Ratio (PSNR) measured and in qualitative terms, i.e., by direct observation of the video sequences on television sets of professional quality. By combining the procedure of non-motion-compensated de-interlacing of digital images of an ELA type and the motion-compensated procedure described above, as illustrated schematically in FIG. 10, it is possible to obtain a digital-image de-interlacing method that enables optimal performance. Neither the spatial procedure nor the temporal procedure just described, in fact, is able to guarantee optimal performance in all the situations that can occur during processing of a video sequence; for this reason, it is necessary to choose each time the technique that produces the best reconstruction. This can be obtained by means of an appropriate decision module to be cascaded to the two blocks of spatial and temporal de-interlacing. In particular, with reference to FIG. 10, there is illustrated the frame FRM, i.e., an interlaced video image, which is sent in parallel at input to a spatial-de-interlacing module SP, which implements the improved non-motion-compensated digital-image de-interlacing procedure described previously with reference to FIG. 3, and to a temporal-de-interlacing module TMP, which implements the improved motion-compensated digital-image de-interlacing procedure described previously with reference to FIGS. 8 and 9. The spatial-de-interlacing module SP supplies at output a spatial reconstruction Tsp, whilst the temporal-de-interlacing module TMP supplies at output a backward temporal reconstruction Tub, given by the unidirectional estimation on the preceding field or backward field, a forward temporal reconstruction Tuf, given by the unidirectional estimation on the subsequent field or forward field, a balanced temporal reconstruction Tbb, given by the balanced bi-directional estimation, and a non-balanced temporal reconstruction Tbn, given by the non-balanced bi-directional estimation. For each square block BK of N×N pixels that composes a reconstructed image RINT at output of the system, a decision module D receives the corresponding spatial reconstruction Tsp and the temporal reconstructions Tub, Tuf, Tbb and Tbn. To each of these reconstructions, or predictors, Tsp, Tub, Tuf, Tbb and Tbn, there is assigned in the decision module D a figure of merit obtained by applying a determined cost function. As a cost function the variance of the block being examined may, for example, be chosen. In fact, given the block BK made up of N×N pixels of values P (i,j), its M-order moment, μM, is: μ M = 1 N 2 ∑ i = 0 N ∑ j = 0 N ( p ( i , j ) ) M ( 7 ) and the variance var is thus defined as the difference between the second-order moment and the first-order moment (i.e., the mean) squared, i.e.,: var=μ2−μ12 Once the variance var, corresponding to a cost, has been calculated for each one of the predictors Tsp, Tub, Tuf, Tbb and Tbn of the block BK to be reconstructed, in the decision module D there is applied a function for choice of the optimal predictor. As a choice function in the decision module D, there can for example be applied a median filter, i.e., a filter that, given a set of values, returns the value that occupies the intermediate position in said set of values. For example, the median of the set of values (10, 80, 20) is 20; the median of the set of values (10, 80, 20, 30) is 25, which is the mean of the two intermediate values 20 and 30. Hence, in the decision module D there is chosen, as best reconstructed block BK for composing the reconstructed image RINT, the block that corresponds to the median of the variances of the individual spatial and temporal predictors. This operation of reconstruction is carried out by means of an appropriate reconstruction module RC set at the output of the decision module D. The reconstruction module RC receives, from the decision module D, the blocks BK chosen by means of the median filter and recomposes the field to be reconstructed MFD. Moreover, this reconstruction module RC receives at input the frame FRM, in such a way as to be able to supply at output the reconstructed image RINT with the fields arranged in an ordered way for a progressive-scan display. The solution described above enables considerable advantages to be achieved as compared to known solutions. The de-interlacing method described guarantees optimal performance in all the situations that can occur during processing of a video sequence, it being able to choose from time to time the technique that produces the best reconstruction. This is obtained by carrying out in an appropriate decision module, operations of application of convenient cost and choice functions, so as to prevent defects of formation of blocks from arising in the reconstructed image. Those skilled in the art will recognize that the method described above may be implemented in a general purpose computer system. FIG. 11 and the following discussion provide a brief, general description of a suitable computing environment in which the invention may be implemented. Although not required, at least one embodiment of the invention can be implemented in the general context of computer-executable instructions, such as program application modules, objects, or macros being executed by a personal computer. Those skilled in the relevant art will appreciate that the invention can be practiced with other computing system configurations, including handheld devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. The invention can be practiced in distributed computing environments where tasks or modules are performed by remote processing devices, which are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices. Referring to FIG. 11, a personal computer referred to herein as a computing system 12 includes a processing unit 13, a system memory 14 and a system bus 16 that couples various system components including the system memory 14 to the processing unit 13. The processing unit 13 may be any logical processing unit, such as one or more central processing units (CPUs), digital signal processors (DSPs), application-specific integrated circuits (ASIC), etc. Unless described otherwise, the construction and operation of the various blocks shown in FIG. 11 are of conventional design. As a result, such blocks need not be described in further detail herein, as they will be understood by those skilled in the relevant art. The system bus 16 can employ any known bus structures or architectures, including a memory bus with memory controller, a peripheral bus, and/or a local bus. The system memory 14 includes read-only memory (“ROM”) 18 and random access memory (“RAM”) 20. A basic input/output system (“BIOS”) 22, which can form part of the ROM 18, contains basic routines that help transfer information between elements within the computing system 12, such as during startup. The computing system 12 also includes one or more spinning media memories such as a hard disk drive 24 for reading from and writing to a hard disk 25, and an optical disk drive 26 and a magnetic disk drive 28 for reading from and writing to removable optical disks 30 and magnetic disks 32, respectively. The optical disk 30 can be a CD-ROM, while the magnetic disk 32 can be a magnetic floppy disk or diskette. The hard disk drive 24, optical disk drive 26 and magnetic disk drive 28 communicate with the processing unit 13 via the bus 16. The hard disk drive 24, optical disk drive 26 and magnetic disk drive 28 may include interfaces or controllers coupled between such drives and the bus 16, as is known by those skilled in the relevant art, for example via an IDE (i.e., Integrated Drive Electronics) interface. The drives 24, 26 and 28, and their associated computer-readable media, provide nonvolatile storage of computer-readable instructions, data structures, program modules and other data for the computing system 12. Although the depicted computing system 12 employs hard disk 25, optical disk 30 and magnetic disk 32, those skilled in the relevant art will appreciate that other types of spinning media memory computer-readable media may be employed, such as, digital video disks (“DVD”), Bernoulli cartridges, etc. Those skilled in the relevant art will also appreciate that other types of computer-readable media that can store data accessible by a computer may be employed, for example, non-spinning media memories such as magnetic cassettes, flash memory cards, RAMs, ROMs, smart cards, etc. Program modules can be stored in the system memory 14, such as an operating system 34, one or more application programs 36, other programs or modules 38, and program data 40. The system memory 14 also includes a browser 41 for permitting the computing system 12 to access and exchange data with sources such as websites of the Internet, corporate intranets, or other networks, as well as other server applications on server computers. The browser 41 is markup language based, such as hypertext markup language (“HTML”), and operate with markup languages that use syntactically delimited characters added to the data of a document to represent the structure of the document. While shown in FIG. 11 as being stored in the system memory, the operating system 34, application programs 36, other program modules 38, program data 40 and browser 41 can be stored on the hard disk 25 of the hard disk drive 24, the optical disk 30 and the optical disk drive 26 and/or the magnetic disk 32 of the magnetic disk drive 28. A user can enter commands and information to the computing system 12 through input devices such as a keyboard 42 and a pointing device such as a mouse 44. Other input devices can include a microphone, joystick, game pad, scanner, etc. These and other input devices are connected to the processing unit 13 through an interface 46 such as a serial port interface that couples to the bus 16, although other interfaces such as a parallel port, a game port or a universal serial bus (“USB”) can be used. A monitor 48 or other display devices may be coupled to the bus 16 via video interface 50, such as a video adapter. The computing system 12 can include other output devices such as speakers, printers, etc. The computing system 12 can operate in a networked environment using logical connections to one or more remote computers. The computing system 12 may employ any known means of communications, such as through a local area network (“LAN”) 52 or a wide area network (“WAN”) or the Internet 54. Such networking environments are well known in enterprise-wide computer networks, intranets, and the Internet. When used in a LAN networking environment, the computing system 12 is connected to the LAN 52 through an adapter or network interface 56 (communicatively linked to the bus 16). When used in a WAN networking environment, the computing system 12 often includes a modem 57 or other device for establishing communications over the WAN/Internet 54. The modem 57 is shown in FIG. 1 as communicatively linked between the interface 46 and the WAN/Internet 54. In a networked environment, program modules, application programs, or data, or portions thereof, can be stored in a server computer (not shown). Those skilled in the relevant art will readily recognize that the network connections shown in FIG. 7 are only some examples of establishing communication links between computers, and other links may be used, including wireless links. The computing system 12 may include one or more interfaces such as slot 58 to allow the addition of devices either internally or externally to the computing system 12. For example, suitable interfaces may include ISA (i.e., Industry Standard Architecture), IDE, PCI (i.e., Personal Computer Interface) and/or AGP (i.e., Advance Graphics Processor) slot connectors for option cards, serial and/or parallel ports, USB ports (i.e., Universal Serial Bus), audio input/output (i.e., I/O) and MIDI/joystick connectors, and/or slots for memory. The term “computer-readable medium” as used herein refers to any medium that participates in providing instructions to processing unit 13 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, hard, optical or magnetic disks 25, 30, 32, respectively. Volatile media includes dynamic memory, such as system memory 14. Transmission media includes coaxial cables, copper wire and fiber optics, including the wires that comprise system bus 16. Transmission media can also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read. Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to processing unit 13 for execution. For example, the instructions may initially be carried on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. The modem 57 local to computer system 10 can receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector coupled to the system bus 16 can receive the data carried in the infrared signal and place the data on system bus 16. The system bus 16 carries the data to system memory 14, from which processing unit 13 retrieves and executes the instructions. The instructions received by system memory 14 may optionally be stored on storage device either before or after execution by processing unit 13. All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet are incorporated herein by reference, in their entirety. Of course, without prejudice the principle of the invention, the details of construction and the embodiments may vary widely with respect to what is described and illustrated herein, without thereby departing from the scope of the present invention, as defined by the annexed claims. It may be noted, in particular, that the procedure proposed can be applied indifferently both to the European television system PAL and to the American television system NTSC, as well as to high-definition TV. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The present invention relates to techniques for digital-image processing, including motion estimation techniques, and has been developed with particular attention paid to its possible application to the processing of television images and to the display of the television signal on displays, such as personal-computer displays of the cathode-ray type, liquid-crystal type or plasma type, which use a progressive-scanning mechanism. Even though in what follows, for reasons of clarity and simplicity of exposition, practically exclusive reference will be made to this application, it must in any case be borne in mind that the significance of application of the invention is more general. The invention is in fact applicable to all techniques of digital-image processing in which there arise operating conditions of the type described in what follows. 2. Description of the Related Art The television system adopted in Europe, i.e., the Phase-Alternate-Line (PAL) system, is characterized by a frame frequency of 25 Hz: this means that it is possible to display 25 images or frames per second, each of which is made up of a grid of 720×576 samples, called pixels (picture elements), arranged in rows. In fact, the raster, i.e., the electron beam that draws the image on the television display, operates at a frequency of 50 Hz, and once every second creates on the display 50 half-images, or fields, each of which is sampled at a different instant in time, with a time interval between said fields of one fiftieth of a second. Each field contains alternately the even rows only or else the odd rows only of a complete image. Consequently, the images displayed on the television screen have their even rows belonging to one field, referred to as even field, and their odd rows belonging to another field, referred to as odd field. When the images are divided in this way, they are referred to as “interlaced” images. The PAL system was originally conceived for systems with cathode-ray displays, but television images are not suited for being displayed on other types of display, such as, for example, computer monitors, or modern televisions with plasma or liquid-crystal displays. These systems, in fact, use a display mechanism referred to as “progressive”, which each time composes on the display a complete image, and not a single field. A television video sequence in PAL format, displayed on these systems, would cause an unpleasant “mosaic” effect, due to the fact that each image is in effect made up of two different interlaced fields. To display the images correctly, it is therefore necessary to subject them to a de-interlacing procedure, which provides for reconstruction of a complete image, starting from a single field. In the case of even fields, the odd lines of the image are reconstructed; in the case of odd fields, the even lines of the image are reconstructed. The reconstructed lines are then added to the original ones, and a complete image or frame is thus obtained. The de-interlacing procedure can be carried out in different ways, which can be reduced to two main categories: motion-compensated procedures; and non-motion-compensated procedures. Motion-compensated (or temporal) de-interlacing procedures use motion-estimation techniques for reconstructing a field starting from temporally preceding and subsequent information, whilst non-motion-compensated (or spatial) de-interlacing procedures use spatial interpolation for reconstructing the even or odd rows of a frame, starting from the odd or even rows, respectively. To carry out the procedure of non-motion-compensated de-interlacing of digital images, it is known to use a procedure referred to as Edge-Line Averaging (ELA). FIG. 1 illustrates a part of the pixels of an image or frame FRM. In this frame FRM, the odd rows that make up a field to be reconstructed MFD are to be reconstructed starting from the even rows. According to the ELA procedure, the pixels belonging to row N, where N is an odd integer, can be reconstructed starting from the adjacent pixels, belonging to the rows N−1 and N+1. In particular, if a pixel to be reconstructed X of the field MFD is in the position M on the row N of the frame FRM, it can be reconstructed using the pixels in the positions M−1, M and M+1 on the aforesaid rows. If A, B and C designate the pixels belonging to a work window FL in positions M−1, M and M+1 in the row N−1 of the frame FRM, and D, E and F designate the pixels in positions M−1, M and M+1 in the row N+1 of the frame FRM, the pixel to be reconstructed X can be reconstructed using the following interpolation formula: X = { A + F 2 if A - F < B - E , C - D B + E 2 if B - E < A - F , C - D C + D 2 if C - D < A - F , B - E ( 1 ) In other words, as can also be inferred from FIG. 1 , the pixel X to be reconstructed is reconstructed by linear interpolation of the most correlated pair of pixels belonging to the nearest rows of the field of opposite parity, the correlation between two pixels being defined as the distance of the respective values. To carry out, instead, the procedure of motion-compensated, or temporal, de-interlacing of digital images for composing the field to be reconstructed MFD, illustrated in FIG. 2 , this field to be reconstructed MFD is, instead, broken down into a series of blocks BK. Each block BK is reconstructed by interpolation of two blocks BK m , BK n belonging to another two frames, of the same parity, that temporally precede and follow, respectively, the frame to be reconstructed containing the field to be reconstructed MFD. The preceding frame includes a field n that contains the block BK n and the following frame includes a field m that contains the block BK m . The pair of blocks is chosen by minimizing a correlation function, such as, for example, the Sum-of-Absolute-Differences (SAD) function, which is defined as follows: if SAD(x,y) is the SAD function between a preceding block BK n of W×H pixels (where W and H are positive integers), set in a position (x,y) in the preceding field n, which has pixels of intensity V n (x+i,y+j), and a corresponding subsequent block BK m , set in a position (x+dx,y+dy) in the subsequent field m, which has pixels of intensity V m (x+dx+i,y+dy+j), then the SAD function is: SAD ( xy ) = ∑ i = 0 W ∑ j = 0 H V n ( x + i , y + j ) - V m ( x + dx + i , y + dy + j ) ( 2 ) The position of the preceding reference block BK n with respect to the block BK to be reconstructed is indicated by a motion vector MV, whilst the position of the subsequent block BK m is indicated by an equal and opposite motion vector designated by −MV in FIG. 2 . In this case, the term “balanced motion estimation” is used, in so far as the two reference blocks, the preceding one BK n and the subsequent one BK m , are in an opposite position with respect to that of the block BK to be reconstructed. For minimizing the correlation function, whether it is the aforesaid SAD function or any other function, it is possible to use any technique of motion estimation, such as for example the full-search technique, which verifies exhaustively all the possibilities within a certain search area, called “search window”. The de-interlacing procedures listed above, however, do not succeed in guaranteeing optimal performance in all the situations that can occur during processing of a video sequence. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>One embodiment of the present invention provides a solution that guarantees optimal performance in the operations of de-interlacing of an interlaced digital image. According to the present invention, one embodiment is directed to a method, another to the corresponding system, and yet another to the corresponding computer product directly loadable into the memory of a digital computer such as a processor. Basically, the solution described herein provides for making a choice between different procedures for de-interlacing digital images that generate different reconstructions, by an operation of evaluation and minimization of a cost function. There are also proposed improved procedures of digital image de-interlacing of a spatial and temporal type. As compared to the known solutions, a solution proposed herein enables a reconstruction to be obtained without appreciable visual defects. | 20050121 | 20100216 | 20050818 | 61920.0 | 0 | YENKE, BRIAN P | METHOD AND SYSTEM FOR DE-INTERLACING DIGITAL IMAGES, AND COMPUTER PROGRAM PRODUCT THEREFOR | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,041,605 | ACCEPTED | Multimodal natural language query system and architecture for processing voice and proximity-based queries | The present invention provides a wireless natural language query system, architecture, and method for processing multimodally-originated queries, including voice and proximity-based queries. The natural language query system includes a Web-enabled device including a speech input module for receiving a voice-based query in natural language form from a user and a location/proximity module for receiving location/proximity information from a location/proximity device. The natural language query system also includes a speech conversion module for converting the voice-based query in natural language form to text in natural language form and a natural language processing module for converting the text in natural language form to text in searchable form. The natural language query system further includes a semantic engine module for converting the text in searchable form to a formal database query and a database-look-up module for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. | 1. A natural language query system for processing voice and proximity-based queries, comprising: a device, comprising: a speech input module for receiving a voice-based query in natural language form from a user; and a location/proximity module for receiving location/proximity information from a location/proximity device; a speech conversion module for converting the voice-based query in natural language form to text in natural language form; a natural language processing module for converting the text in natural language form to text in searchable form; a semantic engine module for converting the text in searchable form to a formal database query; and a database-look-up module for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. 2. The natural language query system of claim 1, wherein the device comprises a device selected from the group consisting of a Web-enabled portable personal computer, a Web-enabled laptop computer, a Web-enabled personal digital assistant, and a Web-enabled phone. 3. The natural language query system of claim 1, wherein the speech input module comprises a speech plug-in and a microphone. 4. The natural language query system of claim 1, wherein the location/proximity module comprises a location/proximity module selected from the group consisting of a radio frequency identification reader and a global positioning system. 5. The natural language query system of claim 1, wherein the location/proximity device comprises a location/proximity device selected from the group consisting of a radio frequency identification tag and a satellite. 6. The natural language query system of claim 1, wherein the speech conversion module resides in a speech server located remotely from the device. 7. The natural language query system of claim 1, wherein the natural language processing module resides in a server located remotely from the device. 8. The natural language query system of claim 1, wherein the semantic engine module resides in a database server located remotely from the device. 9. The natural language query system of claim 1, wherein the database-look-up module resides in a database server located remotely from the device. 10. The natural language query system of claim 1, further comprising a speech output module for delivering the result related to the voice-based query in natural language form to the user. 11. A natural language query architecture for processing voice and proximity-based queries, comprising: a Web-enabled device, comprising: a speech plug-in for receiving a voice-based query in natural language form from a user; and a location/proximity plug-in for receiving location/proximity information from a location/proximity device; a speech conversion algorithm for converting the voice-based query in natural language form to text in natural language form; a natural language processing algorithm for converting the text in natural language form to text in searchable form; a semantic engine algorithm for converting the text in searchable form to a formal database query; and a database-look-up algorithm for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. 12. The natural language query architecture of claim 11, wherein the Web-enabled device comprises a Web-enabled device selected from the group consisting of a Web-enabled portable personal computer, a Web-enabled laptop computer, a Web-enabled personal digital assistant, and a Web-enabled phone. 13. The natural language query architecture of claim 11, wherein the speech input plug-in comprises a speech input plug-in and a microphone. 14. The natural language query architecture of claim 11, wherein the location/proximity plug-in comprises a location/proximity plug-in selected from the group consisting of a radio frequency identification reader and a global positioning system. 15. The natural language query architecture of claim 11, wherein the location/proximity device comprises a location/proximity device selected from the group consisting of a radio frequency identification tag and a satellite. 16. The natural language query architecture of claim 11, wherein the speech conversion algorithm resides in a speech server located remotely from the Web-enabled device. 17. The natural language query architecture of claim 11, wherein the natural language processing algorithm resides in a server located remotely from the Web-enabled device. 18. The natural language query architecture of claim 11, wherein the semantic engine algorithm resides in a database server located remotely from the Web-enabled device. 19. The natural language query architecture of claim 11, wherein the database-look-up algorithm resides in a database server located remotely from the Web-enabled device. 20. The natural language query architecture of claim 11, further comprising a speech output plug-in for delivering the result related to the voice-based query in natural language form to the user. 21. A natural language query method for processing voice and proximity-based queries, comprising: providing a device, comprising: a speech input module for receiving a voice-based query in natural language form from a user; and a location/proximity module for receiving location/proximity information from a location/proximity device; converting the voice-based query in natural language form to text in natural language form using a speech conversion module; converting the text in natural language form to text in searchable form using a natural language processing module; converting the text in searchable form to a formal database query using a semantic engine module; and obtaining a result related to the voice-based query in natural language form from a database using the formal database query and a database-look-up module. 22. The natural language query method of claim 21, wherein the device comprises a device selected from the group consisting of a Web-enabled portable personal computer, a Web-enabled laptop computer, a Web-enabled personal digital assistant, and a Web-enabled phone. 23. The natural language query method of claim 21, wherein the speech input module comprises a speech plug-in and a microphone. 24. The natural language query method of claim 21, wherein the location/proximity module comprises a location/proximity module selected from the group consisting of a radio frequency identification reader and a global positioning system. 25. The natural language query method of claim 21, wherein the location/proximity device comprises a location/proximity device selected from the group consisting of a radio frequency identification tag and a satellite. 26. The natural language query method of claim 21, wherein the speech conversion module resides in a speech server located remotely from the device. 27. The natural language query method of claim 21, wherein the natural language processing module resides in a server located remotely from the device. 28. The natural language query method of claim 21, wherein the semantic engine module resides in a database server located remotely from the device. 29. The natural language query method of claim 21, wherein the database-look-up module resides in a database server located remotely from the device. 30. The natural language query method of claim 21, further comprising delivering the result related to the voice-based query in natural language form to the user using a speech output module. | CROSS-REFERENCE TO RELATED APPLICATION(S) The present non-provisional patent application claims the benefit of U.S. Provisional Patent Application No. 60/631,339, entitled “MULTIMODAL NATURAL LANGUAGE QUERY SYSTEM AND ARCHITECTURE FOR PROCESSING VOICE AND PROXIMITY-BASED QUERIES,” filed Nov. 29, 2004, which is herein incorporated in full by reference. FIELD OF THE INVENTION The present invention relates generally to a wireless multimodal natural language query system and architecture for processing voice and proximity-based queries. More specifically, the present invention relates to a wireless multimodal natural language query system and architecture for processing voice and proximity-based queries including a location or proximity system or device, such as a global positioning system (GPS), radio frequency identification (RFID) device, or the like. This location or proximity system or device provides the multimodal natural language query system and architecture with a plurality of advanced capabilities. BACKGROUND OF THE INVENTION The use of personal computers (PCs), personal digital assistants (PDAs), Web-enabled phones, wireline and wireless networks, the Internet, Web-based query systems and engines, and the like has gained relatively widespread acceptance in recent years. This is due, in large part, to the relatively widespread availability of high-speed, broadband Internet access through digital subscriber lines (DSLs) (including asymmetric digital subscriber lines (ADSLs) and very-high-bit-rate digital subscriber lines (VDSLs)), cable modems, satellite modems, and the like. Thus far, user interaction with PCs, PDAs, Web-enabled phones, wireline and wireless networks, the Internet, Web-based query systems and engines, and the like has been primarily non-voice-based, through keyboards, mice, intelligent electronic pads, monitors, printers, and the like. This has limited the adoption and use of these devices and systems somewhat, and it has long been felt that allowing for accurate, precise, and reliable voice-based user interaction, mimicking normal human interaction, would be advantageous. For example, allowing for accurate, precise, and reliable voice-based user interaction would certainly draw more users to e-commerce, e-support, e-learning, etc., and reduce learning curves. In this context, “mimicking normal human interaction” means that a user would be able to speak a question into a Web-enabled device or the like and the Web-enabled device or the like would respond quickly with an appropriate answer or response, through text, graphics, or synthesized speech, the Web-enabled device or the like not simply converting the user's question into text and performing a routine search, but truly understanding and interpreting the user's question. Thus, if the user speaks a non-specific or incomplete question into the Web-enabled device or the like, the Web-enabled device or the like would be capable of inferring the user's meaning based on context or environment. This is only possible through multimodal input. Several software products currently allow for limited voice-based user interaction with PCs, PDAs, and the like. Such software products include, for example, ViaVoice™ by International Business Machines Corp. and Dragon NaturallySpeaking™ by Scansoft, Inc. These software products, however, allow a user to perform dictation, voice-based command-and-control functions (opening files, closing files, etc.), and voice-based searching (using previously-trained uniform resource locators (URLs)), only after time-consuming, and often inaccurate, imprecise, and unreliable, voice training. Their accuracy rates are inextricably tied to a single user that has provided the voice training. Typical efforts to implement voice-based user interaction in a support and information retrieval context may be seen in U.S. Pat. No. 5,802,526, to Fawcett et al. (Sep. 1, 1998). Typical efforts to implement voice-based user interaction in an Internet context may be seen in U.S. Pat. No. 5,819,220, to Sarukkai et al. (Oct. 6, 1998). U.S. Pat. No. 6,446,064, to Livowsky (Sep. 3, 2002), discloses a system and method for enhancing e-commerce using a natural language interface. The natural language interface allows a user to formulate a query in natural language form, rather than using conventional search terms. In other words, the natural language interface provides a “user-friendly” interface. The natural language interface may process a query even if there is not an exact match between the user-formulated search terms and the content in a database. Furthermore, the natural language interface is capable of processing misspelled queries or queries having syntax errors. The method for enhancing e-commerce using a natural language interface includes the steps of accessing a user interface provided by a service provider, entering a query using a natural language interface, the query being formed in natural language form, processing the query using the natural language interface, searching a database using the processed query, retrieving results from the database, and providing the results to the user. The system for enhancing e-commerce on the Internet includes a user interface for receiving a query in natural language form, a natural language interface coupled to the user interface for processing the query, a service provider coupled to the user interface for receiving the processed query, and one or more databases coupled to the user interface for storing information, wherein the system searches the one or more databases using the processed query and provides the results to the user through the user interface. U.S. Pat. No. 6,615,172, to Bennett et al. (Sep. 2, 2003), discloses an intelligent query system for processing voice-based queries. This distributed client-server system, typically implemented on an intranet or over the Internet accepts a user's queries at the user's PC, PDA, or workstation using a speech input interface. After converting the user's query from speech to text, a two-step algorithm employing a natural language engine, a database processor, and a full-text standardized query language (SQL) database is implemented to find a single answer that best matches the user's query. The system, as implemented, accepts environmental variables selected by the user and is scalable to provide answers to a variety and quantity of user-initiated queries. U.S. Patent Application Publication No. 2001/0039493, to Pustejovsky et al. (Nov. 8, 2001), discloses, in an exemplary embodiment, a system and method for answering voice-based queries using a remote mobile device, e.g., a mobile phone, and a natural language system. U.S. Patent Application Publication No. 2003/0115192, to Kil et al. (Jun. 19, 2003), discloses, in various embodiments, an apparatus and method for controlling a data mining operation by specifying the goal of data mining in natural language, processing the data mining operation without any further input beyond the goal specification, and displaying key performance results of the data mining operation in natural language. One specific embodiment includes providing a user interface having a control for receiving natural language input describing the goal of the data mining operation from the control of the user interface. A second specific embodiment identifies key performance results, providing a user interface having a control for communicating information, and communicating a natural language description of the key performance results using the control of the user interface. In a third specific embodiment, input data determining a data mining operation goal is the only input required by the data mining application. U.S. Patent Application Publication No. 2004/0044516, to Kennewick et al. (Mar. 4, 2004), discloses systems and methods for receiving natural language queries and/or commands and executing the queries and/or commands. The systems and methods overcome some of the deficiencies of other speech query and response systems through the application of a complete speech-based information query, retrieval, presentation, and command environment. This environment makes significant use of context, prior information, domain knowledge, and user-specific profile data to achieve a natural language environment for one or more users making queries or commands in multiple domains. Through this integrated approach, a complete speech-based natural language query and response environment may be created. The systems and methods create, store, and use extensive personal profile information for each user, thereby improving the reliability of determining the context and presenting the expected results for a particular question or command. U.S. Patent Application Publication No. 2004/0117189, to Bennett (Jun. 17, 2004), discloses an intelligent query system for processing voice-based queries. This distributed client-server system, typically implemented on an intranet or over the Internet, accepts a user's queries at the user's PC, PDA, or workstation using a speech input interface. After converting the user's query from speech to text, a natural language engine, a database processor, and a full-text SQL database are implemented to find a single answer that best matches the user's query. Both statistical and semantic decoding are used to assist and improve the performance of the query recognition. Each of the systems, apparatuses, software products, and methods described above suffers from at least one of the following shortcomings. Several of the systems, apparatuses, software products, and methods require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. Several of the systems, apparatuses, software products, and methods are single-modal, meaning that a user may interact with each of the systems, apparatuses, software products, and methods in only one way, i.e. each utilizes only a single voice-based input. As a result of this single-modality, there is no context or environment within which a voice-based search is performed and several of the systems, apparatuses, software products, and methods must perform multiple iterations to pinpoint a result or answer related to the voice-based search. Thus, what is needed are natural language query systems, architectures, and methods for processing voice and proximity-based queries that do not require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. What is also needed are natural language query systems, architectures, and methods that are multimodal, meaning that a user may interact with the natural language query systems, architectures, and methods in a number of ways simultaneously and that the natural language query systems, architectures, and methods utilize multiple inputs in order to create and take into consideration a context or environment within which a voice and/or proximity-based search or the like is performed. In other words, what is needed are natural language query systems, architectures, and methods that mimic normal human interaction, attributing meaning to words based on the context or environment within which they are spoken. What is further needed are natural language query systems, architectures, and methods that perform only a single iteration to pinpoint a result or answer related to a voice and/or proximity-based search or the like. BRIEF SUMMARY OF THE INVENTION In various embodiments, the present invention provides a natural language query system, architecture, and method for processing voice and proximity-based queries that do not require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. The present invention also provides a natural language query system, architecture, and method that are multimodal, meaning that a user may interact with the natural language query system, architecture, and method in a number of ways simultaneously and that the natural language query system, architecture, and method utilize multiple inputs in order to create and take into consideration a context or environment within which a voice and/or proximity-based search or the like is performed. In other words, the present invention provides a natural language query system, architecture, and method that mimic normal human interaction, attributing meaning to words based on the context or environment within which they are spoken. This context or environment may be prior information-based, domain knowledge-based, user-specific profile data-based, and/or, preferably, location or proximity-based. The present invention further provides a natural language query system, architecture, and method that perform only a single iteration to pinpoint a result or answer related to a voice and/or proximity-based search or the like. Functionally, the present invention provides a natural language query system, architecture, and method that do more than simply convert speech to text, use this text to search a database, and convert text to speech. The natural language query system, architecture, and method of the present invention are capable of understanding speech and providing appropriate and useful responses. Off-the-shelf tools are used to incorporate and combine speech recognition, natural language processing (NLP), also referred to as natural language understanding, and speech synthesis technologies. NLP understands grammar (how words connect and how their definitions relate to one another), context, and environment. In one specific embodiment of the present invention, a natural language query system for processing voice and proximity-based queries includes a Web-enabled device including a speech input module for receiving a voice-based query in natural language form from a user and a location/proximity module for receiving location/proximity information from a location/proximity device. The natural language query system also includes a speech conversion module for converting the voice-based query in natural language form to text in natural language form and a natural language processing module for converting the text in natural language form to text in searchable form. The natural language query system further includes a semantic engine module for converting the text in searchable form to a formal database query and a database-look-up module for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. In another specific embodiment of the present invention, a natural language query architecture for processing voice and proximity-based queries includes a Web-enabled device including a speech plug-in for receiving a voice-based query in natural language form from a user and a location/proximity plug-in for receiving location/proximity information from a location/proximity device. The natural language query architecture also includes a speech conversion algorithm for converting the voice-based query in natural language form to text in natural language form and a natural language processing algorithm for converting the text in natural language form to text in searchable form. The natural language query architecture further includes a semantic engine algorithm for converting the text in searchable form to a formal database query and a database-look-up algorithm for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. In a further specific embodiment of the present invention, a natural language query method for processing voice and proximity-based queries includes providing a device including a speech input module for receiving a voice-based query in natural language form from a user and a location/proximity module for receiving location/proximity information from a location/proximity device. The natural language query method also includes converting the voice-based query in natural language form to text in natural language form using a speech conversion module and converting the text in natural language form to text in searchable form using a natural language processing module. The natural language query method further includes converting the text in searchable form to a formal database query using a semantic engine module and obtaining a result related to the voice-based query in natural language form from a database using the formal database query and a database-look-up module. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is illustrated and described herein with reference to various figures, in which like reference numbers denote like components, parts, or steps, and in which: FIG. 1 is a schematic diagram illustrating one embodiment of the multimodal natural language query system and architecture for processing voice and proximity-based queries of the present invention; FIG. 2 is a flow chart illustrating one embodiment of the multimodal natural language query method for processing voice and proximity-based queries of the present invention; and FIG. 3 is a continuing flow chart illustrating one embodiment of the multimodal natural language query method for processing voice and proximity-based queries of the present invention. DETAILED DESCRIPTION OF THE INVENTION In general, the natural language query system and architecture of the present invention incorporate and combine the following technologies: 1. Speech Processing—Speech processing allows PCs, PDAs, Web-enabled phones, and the like to recognize—and, to some extent, understand—spoken language. Spoken language is “eyes free” and “hands free”, allowing a PC, PDA, Web-enabled phone, or the like to be used anywhere. This technology has engendered two types of software products: continuous-speech recognition software products and command-and-control software products. Because a context-free grammar allows a speech recognition engine to reduce recognized words to those contained in a predetermined list, high degrees of speech recognition may be achieved in a speaker-independent environment. A context-free grammar may be used with relatively inexpensive microphones, limited central processing units (CPUs), and no time-consuming, and often inaccurate, imprecise, and unreliable, voice training. Although speech processing technology is not new, speech recognition accuracy rates are just now becoming acceptable for natural language discourse. 2. Speech Synthesis—The ability to mimic speech is useful for applications that require spontaneous user interaction, or in situations where viewing or reading are impractical, such as, for example, when a PC, PDA, Web-enabled phone, or the like provide driving directions or instructions to the driver of a vehicle. In software products aimed at the average user, it is important that output sounds are pleasant and sound human enough to encourage regular use. Several software products now bring relatively inexpensive and effective conversational access to information applications and accelerate the acceptance of speech as a user interface alternative for Web-based and mobile applications, including, for example, Microsoft Speech Server by Microsoft Corp. Microsoft Speech Server currently supports eight languages and is based on the open-standard Speech Application Language Tags (SALT) specification, which extends familiar mark-up languages and leverages the existing Web-development paradigm. 3. Natural Language Processing—NLP systems interpret written, rather than spoken, language and may be found in speech processing systems that begin by converting spoken input into text. Using lexicons and grammar rules, NLP parses sentences, determines underlying meanings, and retrieves or constructs responses. NLP technology's main use is in enabling databases to answer queries presented in the form of questions. Another use is in handling high-volume email. NLP performance may be improved by incorporating a common sense knowledge base—that is, a set of real-world rules. Almost all of the database query languages tend to be rigid and difficult to learn, and it is often difficult for even the most experienced user to get desired information out of a database. A natural language interface to the SQL language overcomes the need for users to master the complexities of the SQL language. 4. English Query—English query (EQ) is a component of Microsoft SQL Server 2000 by Microsoft Corp. that allows users to query databases using plain English. The EQ engine creates a database query that may be executed under program control to return a formatted answer. The development process is at a higher level than traditional programming, but may be mastered by non-programmers with some database background. In order to implement natural language searching, an authoring tool is used to provide domain knowledge to the EQ engine, and to relate database entities to objects in the domain. EQ uses verb relationships and the like to perform natural language parsing of users' questions, which provides better search results than keyword-based technologies. The goal of EQ is to identify and model all of the relationships between entities in a database, creating a semantic model that defines a knowledge doamin. This enables EQ to provide answers to a relatively wide range of questions without having to identify those questions in advance. 5. Input Devices—Adding speech recognition capability to an EQ application with a microphone or the like allows a user to type or speak a question to the EQ application. Such a speech interface may also be incorporated into a PDA or smart phone with wireless Internet capability. The combination of speech recognition and EQ represents a powerful method for a user to quickly access information in a SQL Server database. 6. Multimodality—Multimodality combines graphics, text, audio, and avatar output with text, ink, speech, body attitude, gaze, RFID, GPS, and touch input to provide a greatly enhanced user experience. It is enabled by the convergence of voice, data, and content, and by multimedia, Internet protocol (IP), speech, and wireless technologies hosted on a wide range of devices and device combinations. As compared to single-modal visual and voice applications, multimodal applications are more intuitive and easier to use. A user may select how to best interact with an application, which is especially useful with newer, smaller-form-factor devices. When modalities are used contemporaneously, the resulting decrease in mutual disambiguation (MD) input error rates improves accuracy, performance, and robustness. 7. Radio Frequency Identification—RFID is a generic term for technologies that automatically identify one or more objects via radio waves, using a unique serial number stored in a RFID tag. The RFID tag's antenna, tuned to receive a RFID reader's electromagnetic waves in real time, is able to transmit identification information to the RFID reader. The RFID reader converts the radio waves received from the RFID tag into digital information which, in turn, may be passed on to a business system for processing and/or storage. RFID reader technology may be integrated with PDAs via a PC Card implementation. RFID tags tend to be small and lightweight and may be read through nonmetallic materials. The RFID reader does not have to touch a RFID tag, making RFID ideal for adverse and/or unclean environments. Likewise, RFID does not require line of sight between a tag and a reader, allowing the tags to be hidden under the skin, inside clothes, within the pages of a book, etc., preserving the items usability and aesthetics. RFID tags come in two varieties: passive (low power, short range, and relatively inexpensive) and active (high power, long range, and relatively expensive). Preferably, the natural language query system, architecture, and method of the present invention utilize active RFID tags that run on their own power and transmit over long distances. The battery life of a typical active RFID tag is about five years. The natural language query system and architecture of the present invention incorporate and combine the following exemplary components: Web/Speech/Data Server Running Microsoft Windows 2003 Web Server: Microsoft Internet Information Services (IIS) 6.0 Database: Microsoft SQL Server 2000 SP4 Microsoft SQL Server 2000 English Query with Visual Studio NET 2003 tools Microsoft SQL server 2000 Full-Text Indexing Microsoft Speech Server 1.0 Microsoft Speech Application SDK Version 1.0 Simple Object Access Protocol (SOAP) 3.0 HP iPAQ h5550 Pocket PC Running Microsoft Pocket PC 2003 Premium HP iPAQ FA120A PC Card Expansion Pack Plus Identec Solutions iCard III RFID Reader Identec Solutions iD2, iQ32, and iQ8 RFID Tags Speech Add-In For Microsoft Pocket Internet Explorer D-Link DI-614+Wireless Broadband Router Speech Application Language tags (SALT) Protocol DHTML, JavaScript, VBScript (ASP), CSS Microsoft Visual FoxPro 8.0 SP1 Microsoft Component Services Visual BASIC .NET using Visual Studio .NET 2003 It should be noted that components performing similar functions and/or achieving similar results may also be used. Referring to FIG. 1, in one specific embodiment of the present invention, the natural language query system 10 includes a Web-enabled device 12, such as a portable PC (a laptop PC or the like), a PDA, a Web-enabled phone, or the like capable of accessing one or more interactive Hyper Text Mark-Up Language (HTML) or Dynamic Hyper Text Mark-Up Language (DHTML) Web pages 14 (each utilizing JavaScript, Visual basic Scripting Edition (VBScript), Active Server Pages (ASPs), Cascading Style Sheets (CSSs), etc.) via the Internet using a resident browser application 16, such as Internet Explorer or the like. Preferably, the Web-enabled device 12 is mobile and may be relatively easily carried by a user. The Web-enabled device 12 includes a speech plug-in 18, such as Speech Plug-In for Microsoft Pocket Internet Explorer or the like, and is in communication with a speech server 20, such as Microsoft Speech Server 1.0 or the like. Together, the speech plug-in 18 and the speech server 20 provide the Web-enabled device 12 with the ability to receive a voice-based query from a user and convert the speech to text. Specifically, once a speak button or the like associated with the Web-enabled device 12 has been pushed, the speech plug-in 18 detects that a voice-based query has begun, records the voice-based query, and continues until silence is detected. Optionally, the display of the Web-enabled device 12 may display an audio meter that provides the user with real time feedback regarding volume, background noise, and word gaps that provide the user with an improved interactive experience with the Web-enabled device 12. The speech plug-in 18 then sends the recorded voice-based query to the speech server 20, which converts the voice-based query to text and returns the text to the Web-enabled device 12. Preferably, the user's interaction with the Web-enabled device 12 takes place through a speech-enabled Web-page resident on a remote server 22 running one or more ASPs 24. This Web page is displayed on the display of the Web-enabled device 12. The Web-enabled device 12 also includes a location or proximity system or device, such as a GPS or RFID device. In the event that a RFID device is utilized, the Web-enabled device 12 includes an RFID reader 26, such as an Identec Solutions iCard III RFID Reader or the like. The RFID reader 26 automatically and wirelessly detects and receives information continuously and in real time from one or more active RFID tags 28, such as one or more Identec Solutions iD2 RFID Tags or the like, in the vicinity, each of the one or more RFID tags 28 associated with and containing information about an article of interest, place of interest, etc. Optionally, the RFID reader component 26 includes RFID tag reader class software that controls the interface between the browser of the web-enabled device 12 and the RFID reader engine. This RFID tag reader class software incorporates complex fuzzy logic and enables the accurate reading of the RFID tags 28 in real time in support of a mobile user. In general, the RFID reader 26 (or GPS) provides location or proximity information to the Web-enabled device 12 and the natural language query system 10. This location or proximity information and the converted text associated with the user's voice-based query are sent to the remote server 22 for subsequent processing. Based on the location or proximity information received from the RFID reader 26 and the Web-enabled device 12, the remote server 22 retrieves a relevant set of information, images, and/or links which are sent to the Web-enabled device 12 and displayed in the form of one or more Web-pages on the display of the Web-enabled device 12. If there are no problems with the converted text associated with the user's voice-based query, NLP is then carried out at the remote server 22. First, a semantic engine “interprets” the text associated with the user's voice-based query and converts the text into a formal database query. The semantic engine includes an English query run-time engine 30 and a compiled English query model 32. A database look-up is then performed using the formal database query and the result is sent back to the remote server 22 and finally the Web-enabled device 12, which forms one or more Web-pages incorporating the result. The database look-up is performed by Microsoft Visual FoxPro COM+DLL 34 or the like, a full-text catalog 36, and a SQL server 38. Advantageously, the location or proximity information and the converted text associated with the user's voice-based query received from the Web-enabled device 12 represent multimodal inputs. The location or proximity information provide a context or environment that is used to narrow and streamline the database look-up related to the converted text associated with the user's voice-based query. This is illustrated in the example below. Optionally, the remote server 22 may also create a voice-based response that is sent to the Web-enabled device 12 and converted into a speech output. Because the natural language query system 10 is multimodal, the user can react with the natural language query system 10 by either speaking or by tapping the display of the Web-enabled device 12. For example, when link in the results Web page is tapped, more detail, including images, may be returned to the Web-enabled device 12. Referring to FIGS. 2 and 3, in another specific embodiment of the present invention, the natural language query method 40 includes receiving a voice-based query from a user using the speech plug-in 18 (FIG. 1) of the Web-enabled device 12 (FIG. 1) (Block 42) and converting the voice-based query to text using the speech server 20 (FIG. 1) (Block 46). Specifically, once the speak button or the like associated with the Web-enabled device 12 has been pushed, the speech plug-in 18 detects that a voice-based query has begun, records the voice-based query, and continues until silence is detected. For example, if the user is a patron visiting a particular exhibit in an art museum, the user's query may be “who painted this picture?” As described above, the display of the Web-enabled device 12 may display an audio meter that provides the user with real time feedback regarding volume, background noise, and word gaps that provide the user with an improved interactive experience with the Web-enabled device 12. The speech plug-in 18 then sends the recorded voice-based query to the speech server 20 (Block 44), which converts the voice-based query to text (Block 46) and returns the converted text to the Web-enabled device 12 (Block 48). Preferably, the user's interaction with the Web-enabled device 12 takes place through a speech-enabled Web-page resident on the remote server 22 (FIG. 1) running one or more ASPs 24 (FIG. 1). This Web page is displayed on the display of the Web-enabled device 12. As described above, the RFID reader 26 (FIG. 1) provides location or proximity information to the Web-enabled device 12 and the natural language query system 10 (FIG. 1). This location or proximity information and the converted text associated with the user's voice-based query are sent to the remote server 22 for subsequent processing (Blocks 50 and 52). For example, each of the exhibits in the art museum is preferably equipped with a corresponding RFID tag 28 (FIG. 1). Thus, the Web-enabled device 12 and the natural language query system 10 “know” which painting the user is standing in proximity to when the user asks “who painted this picture?” Based on the location or proximity information received from the RFID reader 26 and the Web-enabled device 12, the remote server 22 retrieves a relevant set of information, images, and/or links which are sent to the Web-enabled device 12 and displayed in the form of one or more Web-pages on the display of the Web-enabled device 12. If there are no problems with the converted text associated with the user's voice-based query, NLP is then carried out at the remote server 22. First, a semantic engine “interprets” the text associated with the user's voice-based query and converts the text into a formal database query (Block 54). The semantic engine includes an English query run-time engine 30 (FIG. 1) and a compiled English query model 32 (FIG. 1). A database look-up is then performed using the formal database query (Block 56) and the result is sent back to the remote server 22 and finally the Web-enabled device 12 (Block 58), which forms one or more Web-pages incorporating the result. Advantageously, the location or proximity information and the converted text associated with the user's voice-based query received from the Web-enabled device 12 represent multimodal inputs. The location or proximity information provide a context or environment that is used to narrow and streamline the database look-up related to the converted text associated with the user's voice-based query. Although the present invention has been illustrated and described with reference to preferred embodiments and examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve similar results. All such equivalent embodiments and examples are within the spirit and scope of the present invention and are intended to be covered by the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>The use of personal computers (PCs), personal digital assistants (PDAs), Web-enabled phones, wireline and wireless networks, the Internet, Web-based query systems and engines, and the like has gained relatively widespread acceptance in recent years. This is due, in large part, to the relatively widespread availability of high-speed, broadband Internet access through digital subscriber lines (DSLs) (including asymmetric digital subscriber lines (ADSLs) and very-high-bit-rate digital subscriber lines (VDSLs)), cable modems, satellite modems, and the like. Thus far, user interaction with PCs, PDAs, Web-enabled phones, wireline and wireless networks, the Internet, Web-based query systems and engines, and the like has been primarily non-voice-based, through keyboards, mice, intelligent electronic pads, monitors, printers, and the like. This has limited the adoption and use of these devices and systems somewhat, and it has long been felt that allowing for accurate, precise, and reliable voice-based user interaction, mimicking normal human interaction, would be advantageous. For example, allowing for accurate, precise, and reliable voice-based user interaction would certainly draw more users to e-commerce, e-support, e-learning, etc., and reduce learning curves. In this context, “mimicking normal human interaction” means that a user would be able to speak a question into a Web-enabled device or the like and the Web-enabled device or the like would respond quickly with an appropriate answer or response, through text, graphics, or synthesized speech, the Web-enabled device or the like not simply converting the user's question into text and performing a routine search, but truly understanding and interpreting the user's question. Thus, if the user speaks a non-specific or incomplete question into the Web-enabled device or the like, the Web-enabled device or the like would be capable of inferring the user's meaning based on context or environment. This is only possible through multimodal input. Several software products currently allow for limited voice-based user interaction with PCs, PDAs, and the like. Such software products include, for example, ViaVoice™ by International Business Machines Corp. and Dragon NaturallySpeaking™ by Scansoft, Inc. These software products, however, allow a user to perform dictation, voice-based command-and-control functions (opening files, closing files, etc.), and voice-based searching (using previously-trained uniform resource locators (URLs)), only after time-consuming, and often inaccurate, imprecise, and unreliable, voice training. Their accuracy rates are inextricably tied to a single user that has provided the voice training. Typical efforts to implement voice-based user interaction in a support and information retrieval context may be seen in U.S. Pat. No. 5,802,526, to Fawcett et al. (Sep. 1, 1998). Typical efforts to implement voice-based user interaction in an Internet context may be seen in U.S. Pat. No. 5,819,220, to Sarukkai et al. (Oct. 6, 1998). U.S. Pat. No. 6,446,064, to Livowsky (Sep. 3, 2002), discloses a system and method for enhancing e-commerce using a natural language interface. The natural language interface allows a user to formulate a query in natural language form, rather than using conventional search terms. In other words, the natural language interface provides a “user-friendly” interface. The natural language interface may process a query even if there is not an exact match between the user-formulated search terms and the content in a database. Furthermore, the natural language interface is capable of processing misspelled queries or queries having syntax errors. The method for enhancing e-commerce using a natural language interface includes the steps of accessing a user interface provided by a service provider, entering a query using a natural language interface, the query being formed in natural language form, processing the query using the natural language interface, searching a database using the processed query, retrieving results from the database, and providing the results to the user. The system for enhancing e-commerce on the Internet includes a user interface for receiving a query in natural language form, a natural language interface coupled to the user interface for processing the query, a service provider coupled to the user interface for receiving the processed query, and one or more databases coupled to the user interface for storing information, wherein the system searches the one or more databases using the processed query and provides the results to the user through the user interface. U.S. Pat. No. 6,615,172, to Bennett et al. (Sep. 2, 2003), discloses an intelligent query system for processing voice-based queries. This distributed client-server system, typically implemented on an intranet or over the Internet accepts a user's queries at the user's PC, PDA, or workstation using a speech input interface. After converting the user's query from speech to text, a two-step algorithm employing a natural language engine, a database processor, and a full-text standardized query language (SQL) database is implemented to find a single answer that best matches the user's query. The system, as implemented, accepts environmental variables selected by the user and is scalable to provide answers to a variety and quantity of user-initiated queries. U.S. Patent Application Publication No. 2001/0039493, to Pustejovsky et al. (Nov. 8, 2001), discloses, in an exemplary embodiment, a system and method for answering voice-based queries using a remote mobile device, e.g., a mobile phone, and a natural language system. U.S. Patent Application Publication No. 2003/0115192, to Kil et al. (Jun. 19, 2003), discloses, in various embodiments, an apparatus and method for controlling a data mining operation by specifying the goal of data mining in natural language, processing the data mining operation without any further input beyond the goal specification, and displaying key performance results of the data mining operation in natural language. One specific embodiment includes providing a user interface having a control for receiving natural language input describing the goal of the data mining operation from the control of the user interface. A second specific embodiment identifies key performance results, providing a user interface having a control for communicating information, and communicating a natural language description of the key performance results using the control of the user interface. In a third specific embodiment, input data determining a data mining operation goal is the only input required by the data mining application. U.S. Patent Application Publication No. 2004/0044516, to Kennewick et al. (Mar. 4, 2004), discloses systems and methods for receiving natural language queries and/or commands and executing the queries and/or commands. The systems and methods overcome some of the deficiencies of other speech query and response systems through the application of a complete speech-based information query, retrieval, presentation, and command environment. This environment makes significant use of context, prior information, domain knowledge, and user-specific profile data to achieve a natural language environment for one or more users making queries or commands in multiple domains. Through this integrated approach, a complete speech-based natural language query and response environment may be created. The systems and methods create, store, and use extensive personal profile information for each user, thereby improving the reliability of determining the context and presenting the expected results for a particular question or command. U.S. Patent Application Publication No. 2004/0117189, to Bennett (Jun. 17, 2004), discloses an intelligent query system for processing voice-based queries. This distributed client-server system, typically implemented on an intranet or over the Internet, accepts a user's queries at the user's PC, PDA, or workstation using a speech input interface. After converting the user's query from speech to text, a natural language engine, a database processor, and a full-text SQL database are implemented to find a single answer that best matches the user's query. Both statistical and semantic decoding are used to assist and improve the performance of the query recognition. Each of the systems, apparatuses, software products, and methods described above suffers from at least one of the following shortcomings. Several of the systems, apparatuses, software products, and methods require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. Several of the systems, apparatuses, software products, and methods are single-modal, meaning that a user may interact with each of the systems, apparatuses, software products, and methods in only one way, i.e. each utilizes only a single voice-based input. As a result of this single-modality, there is no context or environment within which a voice-based search is performed and several of the systems, apparatuses, software products, and methods must perform multiple iterations to pinpoint a result or answer related to the voice-based search. Thus, what is needed are natural language query systems, architectures, and methods for processing voice and proximity-based queries that do not require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. What is also needed are natural language query systems, architectures, and methods that are multimodal, meaning that a user may interact with the natural language query systems, architectures, and methods in a number of ways simultaneously and that the natural language query systems, architectures, and methods utilize multiple inputs in order to create and take into consideration a context or environment within which a voice and/or proximity-based search or the like is performed. In other words, what is needed are natural language query systems, architectures, and methods that mimic normal human interaction, attributing meaning to words based on the context or environment within which they are spoken. What is further needed are natural language query systems, architectures, and methods that perform only a single iteration to pinpoint a result or answer related to a voice and/or proximity-based search or the like. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>In various embodiments, the present invention provides a natural language query system, architecture, and method for processing voice and proximity-based queries that do not require time-consuming, and often inaccurate, imprecise, and unreliable, voice training. The present invention also provides a natural language query system, architecture, and method that are multimodal, meaning that a user may interact with the natural language query system, architecture, and method in a number of ways simultaneously and that the natural language query system, architecture, and method utilize multiple inputs in order to create and take into consideration a context or environment within which a voice and/or proximity-based search or the like is performed. In other words, the present invention provides a natural language query system, architecture, and method that mimic normal human interaction, attributing meaning to words based on the context or environment within which they are spoken. This context or environment may be prior information-based, domain knowledge-based, user-specific profile data-based, and/or, preferably, location or proximity-based. The present invention further provides a natural language query system, architecture, and method that perform only a single iteration to pinpoint a result or answer related to a voice and/or proximity-based search or the like. Functionally, the present invention provides a natural language query system, architecture, and method that do more than simply convert speech to text, use this text to search a database, and convert text to speech. The natural language query system, architecture, and method of the present invention are capable of understanding speech and providing appropriate and useful responses. Off-the-shelf tools are used to incorporate and combine speech recognition, natural language processing (NLP), also referred to as natural language understanding, and speech synthesis technologies. NLP understands grammar (how words connect and how their definitions relate to one another), context, and environment. In one specific embodiment of the present invention, a natural language query system for processing voice and proximity-based queries includes a Web-enabled device including a speech input module for receiving a voice-based query in natural language form from a user and a location/proximity module for receiving location/proximity information from a location/proximity device. The natural language query system also includes a speech conversion module for converting the voice-based query in natural language form to text in natural language form and a natural language processing module for converting the text in natural language form to text in searchable form. The natural language query system further includes a semantic engine module for converting the text in searchable form to a formal database query and a database-look-up module for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. In another specific embodiment of the present invention, a natural language query architecture for processing voice and proximity-based queries includes a Web-enabled device including a speech plug-in for receiving a voice-based query in natural language form from a user and a location/proximity plug-in for receiving location/proximity information from a location/proximity device. The natural language query architecture also includes a speech conversion algorithm for converting the voice-based query in natural language form to text in natural language form and a natural language processing algorithm for converting the text in natural language form to text in searchable form. The natural language query architecture further includes a semantic engine algorithm for converting the text in searchable form to a formal database query and a database-look-up algorithm for using the formal database query to obtain a result related to the voice-based query in natural language form from a database. In a further specific embodiment of the present invention, a natural language query method for processing voice and proximity-based queries includes providing a device including a speech input module for receiving a voice-based query in natural language form from a user and a location/proximity module for receiving location/proximity information from a location/proximity device. The natural language query method also includes converting the voice-based query in natural language form to text in natural language form using a speech conversion module and converting the text in natural language form to text in searchable form using a natural language processing module. The natural language query method further includes converting the text in searchable form to a formal database query using a semantic engine module and obtaining a result related to the voice-based query in natural language form from a database using the formal database query and a database-look-up module. | 20050124 | 20080520 | 20060601 | 58937.0 | G06F1730 | 3 | WONG, LESLIE | MULTIMODAL NATURAL LANGUAGE QUERY SYSTEM AND ARCHITECTURE FOR PROCESSING VOICE AND PROXIMITY-BASED QUERIES | UNDISCOUNTED | 0 | ACCEPTED | G06F | 2,005 |
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11,041,831 | ACCEPTED | NAVIGATING A UAV WITH OBSTACLE AVOIDANCE ALGORITHMS | Methods, systems, and computer program products are provided for navigating a UAV that include piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm. While piloting the UAV, embodiments include reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. Identifying an obstacle in dependence upon the future position may include comprises retrieving obstacle data from a database in dependence the future position. Identifying an obstacle in dependence upon the future position may also include depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position and identifying an obstacle in dependence upon the depiction of the anticipated flight. | 1. A method for navigating a UAV, the method comprising: piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm; while piloting the UAV: reading from a GPS receiver a sequence of GPS data; anticipating a future position of the UAV in dependence upon the sequence of GPS data; identifying an obstacle in dependence upon the future position; selecting an obstacle avoidance algorithm; and piloting the UAV in accordance with the selected obstacle avoidance algorithm. 2. The method of claim 1 wherein identifying an obstacle in dependence upon the future position further comprises retrieving obstacle data from a database in dependence upon the future position. 3. The method of claim 1 wherein identifying an obstacle in dependence upon the future position further comprises: depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position; and identifying an obstacle in dependence upon the depiction of the anticipated flight. 4. The method of claim 1 wherein piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: identifying an intermediate waypoint; flying past the intermediate waypoint; identifying a second intermediate waypoint on an originally anticipated course; flying past the second intermediate waypoint; calculating a new heading to an original destination waypoint; and piloting on the new heading in accordance with a navigational algorithm. 5. The method of claim 1 wherein piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: identifying an intermediate waypoint; flying past the intermediate waypoint; calculating a new heading to an original destination waypoint; and piloting on the new heading in accordance with a navigational algorithm. 6. The method of claim 1 wherein piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: determining an altitude greater than the height of the identified obstacle; and piloting the UAV at the altitude. 7. A system for navigating a UAV, the system comprising: means for piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm; means for reading from a GPS receiver a sequence of GPS data; means for anticipating a future position of the UAV in dependence upon the sequence of GPS data; means for identifying an obstacle in dependence upon the future position; means for selecting an obstacle avoidance algorithm; and means for piloting the UAV in accordance with the selected obstacle avoidance algorithm. 8. The system of claim 7 wherein means for identifying an obstacle in dependence upon the future position further comprises means for retrieving obstacle data from a database in dependence upon the future position. 9. The system of claim 7 wherein means for identifying an obstacle in dependence upon the future position further comprises: means for depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position; and means for identifying an obstacle in dependence upon the depiction of the anticipated flight. 10. The system of claim 7 wherein means for piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: means for identifying an intermediate waypoint; means for flying past the intermediate waypoint; means for identifying a second intermediate waypoint on an originally anticipated course; means for flying past the second intermediate waypoint; means for calculating a new heading to an original destination waypoint; and means for piloting on the new heading in accordance with a navigational algorithm. 11. The system of claim 7 wherein means for piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: means for identifying an intermediate waypoint; means for flying past the intermediate waypoint; means for calculating a new heading to an original destination waypoint; and means for piloting on the new heading in accordance with a navigational algorithm. 12. The system of claim 7 wherein means for piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: means for determining an altitude greater than the height of the identified obstacle; and means for piloting the UAV at the altitude. 13. A computer program product for navigating a UAV, the computer program product comprising: a recording medium; means, recorded on the recording medium, for piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm; means, recorded on the recording medium, for reading from a GPS receiver a sequence of GPS data; means, recorded on the recording medium, for anticipating a future position of the UAV in dependence upon the sequence of GPS data; means, recorded on the recording medium, for identifying an obstacle in dependence upon the future position; means, recorded on the recording medium, for selecting an obstacle avoidance algorithm; and means, recorded on the recording medium, for piloting the UAV in accordance with the selected obstacle avoidance algorithm. 14. The computer program product of claim 13 wherein means, recorded on the recording medium, for identifying an obstacle in dependence upon the future position further comprises means, recorded on the recording medium, for retrieving obstacle data from a database in dependence upon the future position. 15. The computer program product of claim 13 wherein means, recorded on the recording medium, for identifying an obstacle in dependence upon the future position further comprises: means, recorded on the recording medium, for depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position; and means, recorded on the recording medium, for identifying an obstacle in dependence upon the depiction of the anticipated flight. 16. The computer program product of claim 13 wherein means, recorded on the recording medium, for piloting the UAV in accordance with a the selected obstacle avoidance algorithm further comprises: means, recorded on the recording medium, for identifying an intermediate waypoint; means, recorded on the recording medium, for flying past the intermediate waypoint; means, recorded on the recording medium, for identifying a second intermediate waypoint on an originally anticipated course; means, recorded on the recording medium, for flying past the second intermediate waypoint; means, recorded on the recording medium, for calculating a new heading to an original destination waypoint; and means, recorded on the recording medium, for piloting on the new heading in accordance with a navigational algorithm. 17. The computer program product of claim 13 wherein means, recorded on the recording medium, for piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: means, recorded on the recording medium, for identifying an intermediate waypoint; means, recorded on the recording medium, for flying past the intermediate waypoint; means, recorded on the recording medium, for calculating a new heading to an original destination waypoint; and means, recorded on the recording medium, for piloting on the new heading in accordance with a navigational algorithm. 18. The computer program product of claim 13 wherein means, recorded on the recording medium, for piloting the UAV in accordance with the selected obstacle avoidance algorithm further comprises: means, recorded on the recording medium, for determining an altitude greater than the height of the identified obstacle; and means, recorded on the recording medium, for piloting the UAV at the altitude. | BACKGROUND OF THE INVENTION 1. Field of the Invention The field of the invention is data processing, or, more specifically, methods, systems, and products for navigating a UAV with obstacle avoidance algorithms. 2. Description of Related Art Many forms of UAV are available in prior art, both domestically and internationally. Their payload weight carrying capability, their accommodations (volume, environment), their mission profiles (altitude, range, duration), and their command, control and data acquisition capabilities vary significantly. Routine civil access to these various UAV assets is in an embryonic state. Conventional UAVs are typically manually controlled by an operator who may view aspects of a UAV's flight using cameras installed on the UAV with images provided through downlink telemetry. Navigating such UAVs from a starting position to one or more waypoints requires an operator to have specific knowledge of the UAV's flight, including such aspects as starting location, the UAV's current location, waypoint locations, and so on. Operators of prior art UAVs usually are required generally to manually control the UAV from a starting position to a waypoint with little aid from automation. There is therefore an ongoing need for improvement in the area of UAV navigations. SUMMARY OF THE INVENTION Methods, systems, and computer program products are provided for navigating a UAV that include piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm. While piloting the UAV, embodiments include reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. Identifying an obstacle in dependence upon the future position may include comprises retrieving obstacle data from a database in dependence the future position. Identifying an obstacle in dependence upon the future position may also include depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position and identifying an obstacle in dependence upon the depiction of the anticipated flight. Piloting the UAV in accordance with an obstacle avoidance algorithm may include identifying an intermediate waypoint, flying past the intermediate waypoint, identifying a second intermediate waypoint on an originally anticipated course, flying past the second intermediate waypoint, calculating a new heading to an original destination waypoint, and piloting on the new heading in accordance with a navigational algorithm. Piloting the UAV in accordance with an obstacle avoidance algorithm may also include identifying an intermediate waypoint, flying past the intermediate waypoint, calculating a new heading to an original destination waypoint, and piloting on the new heading in accordance with a navigational algorithm. Piloting the UAV in accordance with an obstacle avoidance algorithm may also include determining a new altitude greater than the height of the identified obstacle and piloting the UAV at the new altitude. The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular descriptions of exemplary embodiments of the invention as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts of exemplary embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 sets forth a system diagram illustrating relations among components of an exemplary system for navigating a UAV. FIG. 2 is a block diagram of an exemplary UAV showing relations among components of included automated computing machinery. FIG. 3 is a block diagram of an exemplary remote control device showing relations among components of included automated computing machinery. FIG. 4 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving in a remote control device a user's selection of a GUI map pixel that represents a waypoint for UAV navigation. FIG. 4A sets forth a flow chart illustrating an exemplary method of depicting the flight of the UAV. FIG. 4B sets forth a flow chart illustrating another exemplary method of depicting the flight of the UAV. FIG. 5 sets forth a block diagram that includes a GUI displaying a map and a corresponding area of the surface of the Earth. FIG. 6 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 7 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 6. FIG. 8 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 9 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 8. FIG. 10 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 11 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 10. FIG. 12 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 12A sets forth a line drawing illustrating a method of calculating a heading with a cross wind to achieve a particular ground course. FIG. 13 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 12. FIG. 14 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 15 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 14. FIG. 16 sets forth a flow chart illustrating an exemplary method for navigating a UAV to avoid obstacles. FIG. 17 sets forth a flow chart illustrating an exemplary method of piloting the UAV in accordance with an obstacle avoidance algorithm to avoid a no-fly zone. FIG. 18 sets forth a line drawing illustrating the flight path of a UAV implementing the method of FIG. 17. FIG. 19 sets forth a flow chart illustrating another exemplary method piloting the UAV in accordance with an obstacle avoidance algorithm that does not return to the originally anticipated course. FIG. 20 is a line drawing illustrating the flight path of a UAV implementing the method of FIG. 19. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS Introduction The present invention is described to a large extent in this specification in terms of methods for navigating a UAV with obstacle avoidance algorithms. Persons skilled in the art, however, will recognize that any computer system that includes suitable programming means for operating in accordance with the disclosed methods also falls well within the scope of the present invention. Suitable programming means include any means for directing a computer system to execute the steps of the method of the invention, including for example, systems comprised of processing units and arithmetic-logic circuits coupled to computer memory, which systems have the capability of storing in computer memory, which computer memory includes electronic circuits configured to store data and program instructions, programmed steps of the method of the invention for execution by a processing unit. The invention also may be embodied in a computer program product, such as a diskette or other recording medium, for use with any suitable data processing system. Embodiments of a computer program product may be implemented by use of any recording medium for machine-readable information, including magnetic media, optical media, or other suitable media. Persons skilled in the art will immediately recognize that any computer system having suitable programming means will be capable of executing the steps of the method of the invention as embodied in a program product. Persons skilled in the art will recognize immediately that, although most of the exemplary embodiments described in this specification are oriented to software installed and executing on computer hardware, nevertheless, alternative embodiments implemented as firmware or as hardware are well within the scope of the present invention. Definitions “Airspeed” means UAV airspeed, the speed of the UAV through the air. A “cross track” is a fixed course from a starting point directly to a waypoint. A cross track has a direction, a ‘cross track direction,’ that is the direction straight from a starting point to a waypoint. That is, a cross track direction is the heading that a UAV would fly directly from a starting point to a waypoint in the absence of wind. “GUI” means graphical user interface, a display means for a computer screen. “Heading” means the compass heading of the UAV. “Course” means the direction of travel of the UAV over the ground. That is, a “course” in this specification is what is called, in some lexicons of air navigation, a ‘track.’ In the absence of wind, or in the presence of a straight tailwind or straight headwind, the course and the heading are the same direction. In the presence of cross wind, the course and the heading are different directions. “Position” refers to a location in the air or over the ground. ‘Position’ is typically specified as Earth coordinates, latitude and longitude. A specification of position may also include altitude. A “waypoint” is a position chosen as a destination for navigation of a route. A route has one or more waypoints. That is, a route is composed of waypoints, including at least one final waypoint, and one or more intermediate waypoints. “TDMA” stands for Time Division Multiple Access, a technology for delivering digital wireless service using time-division multiplexing. TDMA works by dividing a radio frequency into time slots and then allocating slots to multiple calls. In this way, a single frequency can support multiple, simultaneous data channels. TDMA is used by GSM. “GSM” stands for Global System for Mobile Communications, a digital cellular standard. GSM at this time is the de facto standard for wireless digital communications in Europe and Asia. “CDPD” stands for Cellular Digital Packet Data, a data transmission technology developed for use on cellular phone frequencies. CDPD uses unused cellular channels to transmit data in packets. CDPD supports data transfer rates of up to 19.2 Kbps. “GPRS” stands for General Packet Radio Service, a standard for wireless data communications which runs at speeds up to 150 Kbps, compared with current GSM systems which cannot support more than about 9.6 Kbps. GPRS, which supports a wide range of speeds, is an efficient use of limited bandwidth and is particularly suited for sending and receiving small bursts of data, such as e-mail and Web browsing, as well as large volumes of data. “EDGE” stands for Enhanced Data Rates for GSM Evolution, a standard for wireless data communications supporting data transfer rates of more than 300 Kbps. GPRS and EDGE are considered interim steps on the road to UMTS. “UMTS” stands for Universal Mobile Telecommunication System, a standard for wireless data communications supporting data transfer rates of up to 2 Mpbs. UMTS is also referred to W-CDMA for Wideband Code Division Multiple Access. Exemplary Architecture Methods, systems, and products for navigating a UAV are: explained with reference to the accompanying drawings, beginning with FIG. 1. FIG. 1 sets forth a system diagram illustrating relations among components of an exemplary system for navigating a UAV. The system of FIG. 1 includes UAV (100) which includes a GPS (Global Positioning System) receiver (not shown) that receives a steady stream of GPS data from satellites (190, 192). For convenience of explanation, only two GPS satellites are shown in FIG. 1, although the GPS satellite network in fact includes 24 GPS satellites. The system of FIG. 1 operates to navigate a UAV by receiving in a remote control device a user's selection of a GUI map pixel that represents a waypoint for UAV navigation. Each such pixel has a location on a GUI map, typically specified as a row and column position. Examples of remote control devices in FIG. 1 include mobile telephone (110), workstation (104), laptop computer (106), and PDA (Personal Digital Assistant) (120). Each such remote control device is capable of supporting a GUI display of a map of the surface of the Earth in which each pixel on the GUI map represents a position on the Earth. Each remote control device also supports at least one user input device through which a user may enter the user's selection of a pixel. Examples of user input devices in the system of FIG. 1 include telephone keypad (122), workstation keyboard (114), workstation joystick (112), laptop keyboard (116) and PDA touch screen (118). The system of FIG. 1 typically is capable of operating a remote control device to map the pixel’ location on the GUI to Earth coordinates of a waypoint and to transmit the coordinates of the waypoint to the UAV (100). In the example of FIG. 1, waypoint coordinates are generally transmitted from remote control devices to the UAV through wireless network (102). Wireless network (102) is implemented using any wireless data transmission technology as will occur to those of skill in the art including, for example, TDMA, GSM, CDPD, GPRS, EDGE, and UMTS. In a preferred embodiment, a data communications link layer is implemented using one of these technologies, a data communications network layer is implemented with the Internet Protocol (“IP”), and a data communications transmission layer is implemented using the Transmission Control Protocol (“TCP”). In such systems, telemetry between the UAV and remote control devices, including waypoint coordinates, are transmitted using an application-level protocol such as, for example, the HyperText Transmission Protocol (“HTTP”), the Wireless Application Protocol (“WAP”), the Handheld Device Transmission Protocol (“HDTP”), or any other data communications protocol as will occur to those of skill in the art. The system of FIG. 1 typically is capable of operating a UAV to read a starting position from a GPS receiver (reference 186 on FIG. 2) on the UAV and pilot the UAV, under control of a navigation computer on the UAV, from a starting position to a waypoint in accordance with a navigation algorithm. The system of FIG. 1 is also capable of reading from the GPS receiver on the UAV a sequence of GPS data representing a flight path of the UAV and depicting the flight of the UAV with 3D computer graphics while the UAV is piloting under control of a navigation computer on the UAV. The system of FIG. 1 is also capable generally of navigating a UAV by piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm. While piloting the UAV, the system of FIG. 1 is capable of reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. UAVs according to embodiments of the present invention typically include, not only an aircraft, but also automated computing machinery capable of receiving GPS data, operating telemetry between the UAV and one or more remote control devices, and navigating a UAV among waypoints. FIG. 2 is a block diagram of an exemplary UAV showing relations among components of included automated computing machinery. In FIG. 2, UAV (100) includes a processor (164), also typically referred to as a central processing unit or ‘CPU.’ The processor may be a microprocessor, a programmable control unit, or any other form of processor useful according to the form factor of a particular UAV as will occur to those of skill in the art. Other components of UAV (100) are coupled for data transfer to processor (164) through system bus (160). UAV (100) includes random access memory or ‘RAM’ (166). Stored in RAM (166) is an application program (158) that implements inventive methods according to embodiments of the present invention. In some embodiments, the application programming runs on an OSGi services framework (156). OSGi Stands for ‘Open Services Gateway Initiative.’ The OSGi specification is a Java-based application layer framework that provides vendor neutral application layer APIs and functions. An OSGi service framework (156) is written in Java and therefore typically runs on a Java Virtual Machine (JVM) (154) which in turn runs on an operating system (150). Examples of operating systems useful in UAVs according to the present invention include Unix, AIX™, and Microsoft Windows™. In OSGi, the framework is a hosting platform for running ‘services’. Services are the main building blocks for creating applications according to the OSGi. A service is a group of Java classes and interfaces that implement a certain feature. The OSGi specification provides a number of standard services. For example, OSGi provides a standard HTTP service that can respond to requests from HTTP clients, such as, for example, remote control devices according to embodiments of the present invention. That is, such remote control devices are enabled to communicate with a UAV having an HTTP service by use of data communications messages in the HTTP protocol. Services in OSGi are packaged in ‘bundles’ with other files, images, and resources that the services need for execution. A bundle is a Java archive or ‘JAR’ file including one or more service implementations, an activator class, and a manifest file. An activator class is a Java class that the service framework uses to start and stop a bundle. A manifest file is a standard text file that describes the contents of the bundle. The services framework in OSGi also includes a service registry. The service registry includes a service registration including the service's name and an instance of a class that implements the service for each bundle installed on the framework and registered with the service registry. A bundle may request services that are not included in the bundle, but are registered on the framework service registry. To find a service, a bundle performs a query on the framework's service registry. The application (158) of FIG. 2 is capable generally of navigating a UAV by piloting the UAV in accordance with a navigation algorithm. While piloting the UAV, the application of FIG. 2 is capable of reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. In the UAV (100) of FIG. 2, software programs and other useful information may be stored in RAM or in non-volatile memory (168). Non-volatile memory (168) may be implemented as a magnetic disk drive such as a micro-drive, an optical disk drive, static read only memory (‘ROM’), electrically erasable programmable read-only memory space (‘EEPROM’ or ‘flash’ memory), or otherwise as will occur to those of skill in the art. UAV (100) includes communications adapter (170) implementing data communications connections (184) to other computers (162), which may be wireless networks, satellites, remote control devices, servers, or others as will occur to those of skill in the art. Communications adapters implement the hardware level of data communications connections through which UAVs transmit wireless data communications. Examples of communications adapters include wireless modems for dial-up connections through wireless telephone networks. UAV (100) includes servos (178). Servos (178) are proportional control servos that convert digital control signals from system bus (160) into actual proportional displacement of flight control surfaces, ailerons, elevators, and the rudder. The displacement of flight control surfaces is ‘proportional’ to values of digital control signals, as opposed to the ‘all or nothing’ motion produces by some servos. In this way, ailerons, for example, may be set to thirty degrees, sixty degrees, or any other supported angle rather than always being only neutral or fully rotated. Several proportional control servos useful in various UAVs according to embodiments of the present invention are available from Futaba®. UAV (100) includes a servo control adapter (172). A servo control adapter (172) is multi-function input/output servo motion controller capable of controlling several servos. An example of such a servo control adapter is the “IOSERVO” model from National Control Devices of Osceola, Mo. The IOSERVO is described on National Control Devices website at www.controlanything.com. UAV (100) includes a flight stabilizer system (174). A flight stabilizer system is a control module that operates servos (178) to automatically return a UAV to straight and level flight, thereby simplifying the work that must be done by navigation algorithms. An example of a flight stabilizer system useful in various embodiments of UAVs according to the present invention is model Co-Pilot™ from FMA, Inc., of Frederick, Md. The Co-Pilot flight stabilizer system identifies a horizon with heat sensors, identifies changes in aircraft attitude relative to the horizon, and sends corrective signals to the servos (178) to keep the UAV flying straight and level. UAV (100) includes an AVCS gyro (176). An AVCS gryo is an angular vector control system gyroscope that provides control signal to the servos to counter undesired changes in attitude such as those caused by sudden gusts of wind. An example of an AVCS gyro useful in various UAVs according to the present invention is model GYA350 from Futaba®. Remote control devices according to embodiments of the present invention typically comprise automated computing machinery capable of receiving user selections of pixel on GUI maps, mapping the pixel to a waypoint location, and transmitting the waypoint location to a UAV. FIG. 3 is a block diagram of an exemplary remote control device showing relations among components of included automated computing machinery. In FIG. 3, remote control device (161) includes a processor (164), also typically referred to as a central processing unit or ‘CPU.’ The processor may be a microprocessor, a programmable control unit, or any other form of processor useful according to the form factor of a particular remote control device as will occur to those of skill in the art. Other components of remote control device (161) are coupled for data transfer to processor (164) through system bus (160). Remote control device (161) includes random access memory or ‘RAM’ (166). Stored in RAM (166) an application program (152) that implements inventive methods of the present invention. The application (152) of FIG. 3 is capable generally of navigating a UAV by piloting the UAV in accordance with a navigation algorithm. While piloting the UAV, the application of FIG. 3 is capable of reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. In some embodiments, the application program (152) is OSGi compliant and therefore runs on an OSGi services framework installed (not shown) on a JVM (not shown). In addition, software programs and further information for use in implementing methods of navigating a UAV according to embodiments of the present invention may be stored in RAM or in non-volatile memory (168). Non-volatile memory (168) may be implemented as a magnetic disk drive such as a micro-drive, an optical disk drive, static read only memory (‘ROM’), electrically erasable programmable read-only memory space (‘EEPROM’ or ‘flash’ memory), or otherwise as will occur to those of skill in the art. Remote control device (161) includes communications adapter (170) implementing data communications connections (184) to other computers (162), including particularly computes on UAVs. Communications adapters implement the hardware level of data communications connections through which remote control devices communicate with UAVs directly or through networks. Examples of communications adapters include modems for wired dial-up connections, Ethernet (IEEE 802.3) adapters for wired LAN connections, 802.11b adapters for wireless LAN connections, and Bluetooth adapters for wireless microLAN connections. The example remote control device (161) of FIG. 3 includes one or more input/output interface adapters (180). Input/output interface adapters in computers implement user-oriented input/output through, for example, software drivers and computer hardware for controlling output to display devices (185) such as computer display screens, as well as user input from user input devices (182) such as keypads, joysticks, keyboards, and touch screens. Navigating a UAV with On-Board Navigation Algorithms with Flight Depiction FIG. 4 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving (402) in a remote control device a user's selection of a GUI map pixel (412) that represents a waypoint for UAV navigation. The pixel has a location on the GUI. Such a GUI map display has many pixels, each of which represents at least one position on the surface of the Earth. A user selection of a pixel is normal GUI operations to take a pixel location, row and column, from a GUI input/output adapter driven by a user input device such as a joystick or a mouse. The remote control device can be a traditional ‘ground control station,’ an airborne PDA or laptop, a workstation in Earth orbit, or any other control device capable of accepting user selections of pixels from a GUI map. The method of FIG. 4 includes mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414). As discussed in more detail below with reference to FIG. 5, mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) typically includes mapping pixel boundaries of the GUI map to corresponding Earth coordinates and identifying a range of latitude and a range of longitude represented by each pixel. Mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) also typically includes locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map. The method of FIG. 4 also includes transmitting (406) the coordinates of the waypoint to the UAV (100). Transmitting (406) the coordinates of the waypoint to the UAV (100) may be carried out by use of any data communications protocol, including, for example, transmitting the coordinates as form data, URI encoded data, in an HTTP message, a WAP message, an HDML message, or any other data communications protocol message as will occur to those of skill in the art. The method of FIG. 4 also includes reading (408) a starting position from a GPS receiver on the UAV (100) and piloting (410) the UAV, under control of a navigation computer on the UAV, from the starting position to the waypoint in accordance with a navigation algorithm (416). Methods of piloting a UAV according to a navigation algorithm are discussed in detail below in this specification. While piloting the UAV from the starting position to the waypoint, the method of FIG. 4 also includes reading (418) from the GPS receiver a sequence of GPS data representing a flight path of the UAV and depicting (420) the flight of the UAV with 3D computer graphics, including a computer graphic display of a satellite image of the Earth, in dependence upon the GPS data. In the method of FIG. 4, depicting (420) the flight of the UAV includes determining (444) a display attitude of the UAV in dependence upon the sequence of GPS data. Display attitude is not based upon actual attitude data such as would be had from gyro sensors, for example. In this disclosure, ‘display attitude’ refers to data describing orientation of a display image depicting a flight. The display attitude describes flight orientation in terms of roll, pitch, and yaw values derived from GPS data, not from measures of actual roll, pitch, and yaw. In the method of FIG. 4, determining (444) a display attitude of the UAV in dependence upon the sequence of GPS data typically also includes detecting changes in the UAV's course from the sequence of GPS data and determining a display roll angle in dependence upon the detected course changes. In some embodiments, a sequence of GPS locations is used to calculate a rate of change of course, a value measured in degrees per second. In such embodiments, display roll angle often is then determined linearly according to the rate of course change, so that a displayed angle of the wings on a UAV icon on a GUI display is proportional to the rate of course change. The faster the course change, the steeper the display roll angle. It is useful to note, however, that there is no required relationship between course change rate and display attitude. Embodiments of UAV navigation systems according to embodiments of the present invention may utilize no data whatsoever describing or representing the actual physical flight attitude of a UAV. The determinations of ‘display attitude’ are determination of values for data structures affecting a GUI display on a computer, not depictions of actual UAV attitude. To the extent that display attitudes are determined in calculated linear relations to actual position changes or course change rates, such display attitudes may result in displays that model fairly closely the actual flight attitude of a UAV. This is not a limitation of the invention, however. In fact, in some embodiments there is no attempt at all to determine display attitudes that closely model actual flight attitudes. Some embodiments consider it sufficient, for example, upon detecting a clockwise turn, always to simply assign a display roll angle of thirty degrees without more. Such embodiments do give a visual indication of roll, thereby indicating a turn, but they do not attempt to indicate an actual rate of change by varying the roll angle. In the method of FIG. 4, determining (444) a display attitude of the UAV in dependence upon the sequence of GPS data may also include detecting changes in the UAV's course from the sequence of GPS data and determining a display yaw angle in dependence upon the detected course changes. In the method of FIG. 4, determining (444) a display attitude of the UAV in dependence upon the sequence of GPS data may also include detecting changes in the UAV's altitude from the sequence of GPS data and determining a display pitch angle in dependence upon the detected altitude changes. FIG. 4A sets forth a flow chart illustrating an exemplary method of depicting the flight of the UAV. In the method of FIG. 4A, depicting the flight of the UAV includes determining (422), on the UAV, a display attitude of the UAV in dependence upon the sequence of GPS data (430). In the method of FIG. 4A, depicting the flight of the UAV includes calculating (424), on the UAV, from the sequence of GPS data, the UAV's course. In the method of FIG. 4A, depicting the flight of the UAV includes creating (426), on the UAV, images for display in dependence upon the display attitude, the course, and a satellite image (432) stored on the UAV and downloading (428) the images for display from the UAV to the remote control device. FIG. 4B sets forth a flow chart illustrating another exemplary method of depicting the flight of the UAV. In the method of FIG. 4B, depicting the flight of the UAV includes downloading (434) the GPS sequence (430) from the UAV (100) to the remote control device and determining (436), in the remote control device, a display attitude of the UAV in dependence upon the sequence of GPS data. In the method of FIG. 4B, depicting the flight of the UAV includes calculating (438), in the remote control device, from the sequence of GPS data, the UAV's course. In the method of FIG. 4B, depicting the flight of the UAV includes creating (440), in the remote control device, images for display in dependence upon the display attitude, the course, and a satellite image (442) stored on the remote control device. Whether the images for display are created on the UAV or on the remote control device, UAV navigation systems according to embodiments of the present invention typically create images for display by use of 3D graphics rendering engines. One example of such an engine is DarkBasic™, from Enteractive Software, Inc., of Hartford, Conn. This example is discussed in terms of DarkBasic, but the use of DarkBasic is not a limitation of the present invention. Many other 3D graphics engines may be used, including APIs for OpenGL, DirectX, Direct3D, and others as will occur to those of skill in the art. DarkBasic provides its API as an extended version of the Basic programming language for orienting a view of a JPEG map of the Earth's surface in accordance with data describing the location of a UAV over the Earth and the UAV's attitude in terms of roll, pitch, yaw, and course. Satellite images of the Earth's surface in the form of JPEG maps suitable for use in DarkBasic rendering engines are available, for example, from Satellite Imaging Corporation of Houston, Tex. The DarkBasic API commands “GET IMAGE” and “LOAD IMAGE” import JPEG images into a DarkBasic rendering engine. DarkBasic “CAMERA” commands are used to orient a view of a JPEG map. The DarkBasic command “POSITION CAMERA” may be used to set an initial view position to a starting point and to move the view position to new locations in dependence upon a sequence GPS data. The DarkBasic command “POINT CAMERA” may be used to orient the view to a UAV's course. When display attitudes are determined according to methods of the current invention, the DarkBasic commands “TURN CAMERA LEFT” and “TURN CAMERA RIGHT” may be used to orient the view according to display yaw angle; the DarkBasic commands “PITCH CAMERA UP” and “PITCH CAMERA DOWN” may be used to orient the view according to display pitch angle; and the DarkBasic commands “ROLL CAMERA LEFT” and “ROLL CAMERA RIGHT” may be used to orient the view according to display roll angle. Macros Although the flow chart of FIG. 4 illustrates navigating a UAV to a single waypoint, as a practical matter, embodiments of the present invention support navigating a UAV along a route having many waypoints, including a final waypoint and one or more intermediate waypoints. That is, methods of the kind illustrated in FIG. 4 may also include receiving user selections of a multiplicity of GUI map pixels representing waypoints, where each pixel has a location on the GUI and mapping each pixel location to Earth coordinates of a waypoint. Such methods of navigating a UAV can also include assigning one or more UAV instructions to each waypoint and transmitting the coordinates of the waypoints and the UAV instructions to the UAV. A UAV instruction typically includes one or more instructions for a UAV to perform a task in connection with a waypoint. Exemplary tasks include turning on or off a camera installed on the UAV, turning on or off a light installed on the UAV, orbiting a waypoint, or any other task that will occur to those of skill in the art. Such exemplary methods of navigating a UAV also include storing the coordinates of the waypoints and the UAV instructions in computer memory on the UAV, piloting the UAV to each waypoint in accordance with one or more navigation algorithms, and operating the UAV at each waypoint in accordance with the UAV instructions for each waypoint. UAV instructions to perform tasks in connection with a waypoint may be encoded in, for example, XML (the eXtensible Markup Language) as shown in the following exemplary XML segment: <UAV-Instructions> <macro> <waypoint> 33° 44′ 10″ N 30° 15′ 50″ W </waypoint> <instruction> orbit </instruction> <instruction> videoCameraON </instruction> <instruction> wait30minutes </instruction> <instruction> videoCameraOFF </instruction> <instruction> nextWaypoint <instruction> </macro> <macro> </macro> <macro> </macro> <macro> </macro> <UAV-instructions> This XML example has a root element named ‘UAV-instructions.’ The example contains several subelements named ‘macro.’ One ‘macro’ subelement contains a waypoint location representing an instruction to fly to 33° 44′ 10″ N 30° 15′ 50″ W. That macro subelement also contains several instructions for tasks to be performed when the UAV arrives at the waypoint coordinates, including orbiting around the waypoint coordinates, turning on an on-board video camera, continuing to orbit for thirty minutes with the camera on, turning off the video camera, and continuing to a next waypoint. Only one macro set of UAV instructions is shown in this example, but that is not a limitation of the invention. In fact, such sets of UAV instructions may be of any useful size as will occur to those of skill in the art. Pixel Mapping For further explanation of the process of mapping pixels' locations to Earth coordinates, FIG. 5 sets forth a block diagram that includes a GUI (502) displaying a map (not shown) and a corresponding area of the surface of the Earth (504). The GUI map has pixel boundaries identified as Row1, Col1; Row1, Col100; Row100, Col100; and Row100, Col1. In this example, the GUI map is assumed to comprise 100 rows of pixels and 100 columns of pixels. This example of 100 rows and columns is presented for convenience of explanation; it is not a limitation of the invention. GUI maps according to embodiments of the present invention may include any number of pixels as will occur to those of skill in the art. The illustrated area of the surface of the Earth has corresponding boundary points identified as Lat1, Lon1; Lat1, Lon2; Lat2, Lon2; and Lat2, Lon1. This example assumes that the distance along one side of surface area (504) is 100 nautical miles, so that the distance expressed in terms of latitude or longitude between boundary points of surface area (504) is 100 minutes or 1° 40′. In typical embodiments, mapping a pixel's location on the GUI to Earth coordinates of a waypoint includes mapping pixel boundaries of the GUI map to Earth coordinates. In this example, the GUI map boundary at Row1, Col1 maps to the surface boundary point at Lat1, Lon2; the GUI map boundary at Row2, Col2 maps to the surface boundary point at Lat1, Lon2; the GUI map boundary at Row2, Col2 maps to the surface boundary point at Lat2, Lon2; the GUI map boundary at Row2, Col1 maps to the surface boundary point at Lat2, Lon1. Mapping a pixel's location on the GUI to Earth coordinates of a waypoint typically also includes identifying a range of latitude and a range of longitude represented by each pixel. The range of latitude represented by each pixel may be described as (Lat2−Lat1)/Nrows, where (Lat2−Lat1) is the length in degrees of the vertical side of the corresponding surface (504), and Nrows is the number of rows of pixels. In this example, (Lat2−Lat1) is 1° 40′ or 100 nautical miles, and Nrows is 100 rows of pixels. The range of latitude represented by each pixel in this example therefore is one minute of arc or one nautical mile. Similarly, the range of longitude represented by each pixel may be described as (Lon2−Lon1)/Ncols, where (Lon2−Lon1) is the length in degrees of the horizontal side of the corresponding surface (504), and Ncols is the number of columns of pixels. In this example, (Lon2−Lon1) is 1° 40′ or 100 nautical miles, and Ncols is 100 columns of pixels. The range of longitude represented by each pixel in this example therefore is one minute of arc or one nautical mile. Mapping a pixel's location on the GUI to Earth coordinates of a waypoint typically also includes locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map. The region is the portion of the surface corresponding to the pixel itself. That region is located generally by multiplying in both dimensions, latitude and longitude, the range of latitude and longitude by column or row numbers of the pixel location on the GUI map. That is, a latitude for the surface region of interest is given by Expression 1. Lat1+Prow((Lat2−Lat1)/Nrows) (Exp. 1) In Expression 1: Lat1 is the latitude of an origin point for the surface area (504) corresponding generally to the GUI map, Prow is the row number of the pixel location on the GUI map, and ((Lat2−Lat1)/Nrows) is the range of latitude represented by the pixel. Similarly, a longitude for the surface region of interest is given by Expression 2. Lon1+Pcol((Lon2−Lon1)/Ncols) (Exp. 2) In Expression 2: Lon1 is the longitude of an origin point for the surface area (504) corresponding generally to the GUI map, Pcol is the column number of the pixel location on the GUI map, and ((Lon2−Lon1)/Ncols) is the range of longitude represented by the pixel. Referring to FIG. 5 for further explanation, Expressions 1 and 2 taken together identify a region (508) of surface area (504) that corresponds to the location of pixel (412) mapping the pixel location to the bottom left corner (506) of the region (508). Advantageously, however, many embodiments of the present invention further map the pixel to the center of the region by adding one half of the length of the region's sides to the location of the bottom left corner (506). More particularly, locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map, as illustrated by Expression 3, may include multiplying the range of longitude represented by each pixel by a column number of the selected pixel, yielding a first multiplicand; and multiplying the range of longitude represented by each pixel by 0.5, yielding a second multiplicand; adding the first and second multiplicands to an origin longitude of the GUI map. Lon1+Pcol((Lon2−Lon1)/Ncols)+0.5((Lon2−Lon1)/Ncols) (Exp. 3) In Expression 3, the range of longitude represented by each pixel is given by ((Lon2−Lon1)/Ncols), and the first multiplicand is Pcol((Lon2−Lon1)/Ncols). The second multiplicand is given by 0.5((Lon2−Lon1)/Ncols). Similarly, locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map, as illustrated by Expression 4, typically also includes multiplying the range of latitude represented by each pixel by a row number of the selected pixel, yielding a third multiplicand; multiplying the range of latitude represented by each pixel by 0.5, yielding a fourth multiplicand; and adding the third and fourth multiplicands to an origin latitude of the GUI map. Lat1+Prow((Lat2−Lat1)/Nrows)+0.5((Lat2−Lat1)/Nrows) (Exp. 4) In Expression 4, the range of latitude represented by each pixel is given by ((Lat2−Lat1)/Nrows), and the third multiplicand is Prow((Lat2−Lat1)/Nrows). The fourth multiplicand is given by 0.5((Lat2−Lat1)/Nrows). Expressions 3 and 4 taken together map the location of pixel (412) to the center (510) of the located region (508). Navigation on a Heading to a Waypoint An exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 6 and 7. FIG. 6 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm, and FIG. 7 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 6. The method of FIG. 6 includes periodically repeating (610) the steps of: reading (602) from the GPS receiver a current position of the UAV; calculating (604) a heading from the current position to the waypoint; turning (606) the UAV to the heading; and flying (608) the UAV on the heading. In this method, if Lon1, Lat1 is taken as the current position, and Lon2, Lat2 is taken as the waypoint position, then the heading may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). FIG. 7 shows the effect of the application of the method of FIG. 6. In the example of FIG. 7, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (716) results from periodic calculations according to the method of FIG. 6 of a new heading straight from a current location to the waypoint. FIG. 7 shows periodic repetitions of the method of FIG. 6 at plot points (710, 712, 714). For clarity of explanation, only three periodic repetitions are shown, although that is not a limitation of the invention. In fact, any number of periodic repetitions may be used as will occur to those of skill in the art. Navigation with Headings Set to a Cross Track Direction A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 8 and 9. FIG. 8 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm, and FIG. 9 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 8. The method of FIG. 8 includes identifying (802) a cross track between the starting point and the waypoint. A cross track is a fixed course from a starting point directly to a waypoint. If Lon1, Lat1 is taken as the position of a starting point, and Lon2, Lat2 is taken as the waypoint position, then a cross track is identified by Lon1, Lat1 and Lon2, Lat2. A cross track has a direction, a ‘cross track direction,’ that is the direction straight from a starting point to a waypoint, and it is often useful to characterize a cross track by its cross track direction. The cross track direction for a cross track identified by starting point Lon1, Lat1 and waypoint position Lon2, Lat2 may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). The method of FIG. 8 includes periodically repeating (810) the steps of: reading (804) from the GPS receiver a current position of the UAV; calculating (806) a shortest distance between the current position and the cross track; and if the shortest distance between the current position and the cross track is greater than a threshold distance, piloting (812) the UAV toward the cross track, and, upon arriving at the cross track, piloting (814) the UAV in a cross track direction toward the waypoint. FIG. 9 illustrates calculating a shortest distance between the current position and a cross track. In the example of FIG. 9, calculating a shortest distance between the current position and a cross track includes calculating the distance from a current position (912) to the waypoint (704). In the example of FIG. 9, the distance from the current position (912) to the waypoint (704) is represented as the length of line (914). For current position Lon1, Lat1 and waypoint position Lon2, Lat2, the distance from a current position (912) to the waypoint (704) is given by the square root of (Lat2−Lat1)2+(Lon2−Lon1)2. In this example, calculating a shortest distance between the current position and a cross track also includes calculating the angle (910) between a direction from the current position to the waypoint and a cross track direction. In the example of FIG. 9, the direction from the current position (912) to the waypoint (704) is represented as the direction of line (914). In the example of FIG. 9, the cross track direction is the direction of cross track (706). The angle between a direction from the current position to the waypoint and a cross track direction is the difference between those directions. In the current example, calculating a shortest distance between the current position and a cross track also includes calculating the tangent of the angle between a direction from the current position to the waypoint and a cross track direction and multiplying the tangent of the angle by the distance from the current position to the waypoint. FIG. 9 also shows the effect of the application of the method of FIG. 8. In the example of FIG. 9, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (904) results from periodic calculations according to the method of FIG. 8 of a shortest distance between a current position and the cross track (706), flying the UAV back to the cross track and then in the direction of the cross track whenever the distance from the cross track exceeds a predetermined threshold distance. Headings set to Cross Track Direction with Angular Thresholds A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 10 and 11. FIG. 10 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm, and FIG. 11 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 10. In the method of FIG. 10, piloting in accordance with a navigation algorithm includes identifying (1002) a cross track having a cross track direction between the starting point and the waypoint. As described above, a cross track is identified by a position of a starting point and a waypoint position. For a starting point position of Lon1, Lat1 and a waypoint position of Lon2, Lat2, a cross track is identified by Lon1, Lat1 and Lon2, Lat2. In addition, it is often also useful to characterize a cross track by its cross track direction. The cross track direction for a cross track identified by starting point Lon1, Lat1 and waypoint position Lon2, Lat2 may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). In the method of FIG. 10, piloting in accordance with a navigation algorithm also includes repeatedly (1010) carrying out the steps of reading (1004) from the GPS receiver a current position of the UAV; calculating (1006) an angle between the direction from the current position to the waypoint and a cross track direction; and, if the angle is greater than a threshold angle, piloting (1012) the UAV toward the cross track, and, upon arriving at the cross track, piloting (1014) the UAV in the cross track direction. Piloting toward the cross track is carried out by turning to a heading no more than ninety degrees from the cross track direction, turning to the left if the current position is right of the cross track and to the right if the current position is left of the cross track. Piloting in the cross track direction means turning the UAV to the cross track direction and then flying straight and level on the cross track direction. That is, in piloting in the cross track direction, the cross track direction is set as the compass heading for the UAV. FIG. 11 shows the effect of the application of the method of FIG. 10. In the example of FIG. 11, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (1104) results from periodically flying the UAV, according to the method of FIG. 10, back to the cross track and then in the direction of the cross track whenever an angle between the direction from the current position to the waypoint and a cross track direction exceeds a predetermined threshold angle. In many embodiments of the method of FIG. 10, the threshold angle is a variable whose value varies in dependence upon a distance between the UAV and the waypoint. In typical embodiments that vary the threshold angle, the threshold angle is increased as the UAV flies closer to the waypoint. It is useful to increase the threshold angle as the UAV flies closer to the waypoint to reduce the risk of excessive ‘hunting’ on the part of the UAV. That is, because the heading is the cross track direction, straight to the WP rather than cross wind, if the angle remains the same, the distance that the UAV needs to be blown off course to trigger a return to the cross track gets smaller and smaller until the UAV is flying to the cross track, turning to the cross track direction, getting blown immediately across the threshold, flying back the cross track, turning to the cross track direction, getting blown immediately across the threshold, and so on, and so on, in rapid repetition. Increasing the threshold angle as the UAV flies closer to the waypoint increases the lateral distance available for wind error before triggering a return to the cross track, thereby reducing this risk of excessive hunting. Navigation on a Course to a Waypoint A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 12, 12A, and 13. FIG. 12 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 12A sets forth a line drawing illustrating a method of calculating a heading with a cross wind to achieve a particular ground course. And FIG. 13 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 12. In the method of FIG. 12, piloting in accordance with a navigation algorithm comprises periodically repeating (1212) the steps of reading (1202) from the GPS receiver a current position of the UAV; calculating (1204) a direction to the waypoint from the current position; calculating a heading in dependence upon wind speed, wind direction, airspeed, and the direction to the waypoint; turning (1208) the UAV to the heading; and flying (1210) the UAV on the heading. FIG. 12A illustrates calculating (1206) a heading in dependence upon wind speed, wind direction, airspeed, and the direction to the waypoint. FIG. 12A sets forth a line drawing illustrating relations among several pertinent vectors, a wind velocity (1222), a resultant velocity (1224), and a UAV's air velocity (1226). A velocity vector includes a speed and a direction. These vectors taken together represent wind speed, wind direction, airspeed, and the direction to the waypoint. In the example of FIG. 12A, the angle B is a so-called wind correction angle, an angle which subtracted from (or added to, depending on wind direction) a direction to a waypoint yields a heading, a compass heading for a UAV to fly so that its resultant ground course is on a cross track. A UAV traveling at an airspeed of ‘a’ on heading (D-B) in the presence of a wind speed ‘b’ with wind direction E will have resultant ground speed ‘c’ in direction D. In FIG. 12A, angle A represents the difference between the wind direction E and the direction to the waypoint D. In FIG. 12A, the wind velocity vector (1222) is presented twice, once to show the wind direction as angle E and again to illustrate angle A as the difference between angles E and D. Drawing wind velocity (1222) to form angle A with the resultant velocity (1224) also helps explain how to calculate wind correction angle B using the law of sines. Knowing two sides of a triangle and the angle opposite one of them, the angle opposite the other may be calculated, in this example, by B=sin−1(b(sin A)/a). The two known sides are airspeed ‘a’ and wind speed ‘b.’ The known angle is A, the angle opposite side ‘a,’ representing the difference between wind direction E and direction to the waypoint D. Calculating a heading, angle F on FIG. 12A, is then carried out by subtracting the wind correction angle B from the direction to the waypoint D. FIG. 13 shows the effect of the application of the method of FIG. 12. In the example of FIG. 13, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (1316) results from periodic calculations according to the method of FIG. 12 of a new heading straight whose resultant with a wind vector is a course straight from a current location to the waypoint. FIG. 13 shows periodic repetitions of the method of FIG. 12 at plot points (1310, 1312, 1314). For clarity of explanation, only three periodic repetitions are shown, although that is not a limitation of the invention. In fact, any number of periodic repetitions may be used as will occur to those of skill in the art. Navigation on a Course set to a Cross Track Direction A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 14 and 15. FIG. 14 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm, and FIG. 15 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 14. The method of FIG. 14 includes identifying (1402) a cross track and calculating (1404) a cross track direction from the starting position to the waypoint. In the method of FIG. 14, piloting in accordance with a navigation algorithm is carried out by periodically repeating the steps of reading (1406) from the GPS receiver a current position of the UAV; calculating (1408) a shortest distance between the cross track and the current position; and, if the shortest distance between the cross track and the current position is greater than a threshold distance, piloting (1412) the UAV to the cross track. Upon arriving at the cross track, the method includes: reading (1414) from the GPS receiver a new current position of the UAV; calculating (1416), in dependence upon wind speed, wind direction, airspeed, and the cross track direction, a new heading; turning (1418) the UAV to the new heading; and flying (1420) the UAV on the new heading. FIG. 15 shows the effect of the application of the method of FIG. 14. In the example of FIG. 15, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (1504) results from periodic calculations according to the method of FIG. 14 of a shortest distance between a current position and the cross track (706), flying the UAV back to the cross track, and, upon arriving at the cross track, calculating a new heading (1502, 1505, and 1506) and flying the UAV on the new heading. Navigating a UAV with Obstacle Avoidance Algorithms Successful navigation of a UAV often requires identifying and avoiding obstacles that would otherwise disrupt the flight of the UAV. Such obstacles may be physical three dimensional objects such as buildings, mountains, and others that will occur to those of skill in the art. Alternatively, obstacles may also be two dimensional geographic areas such as no-fly zones. A ‘no-fly zone’ is a geographic region over which the UAV is forbidden to fly. FIG. 16 sets forth a flow chart illustrating an exemplary method for navigating a UAV to avoid obstacles that includes piloting (410) the UAV (100), under control of a navigation computer, in accordance with a navigation algorithm (416). Piloting (410) the UAV (100) according to the method of FIG. 16 typically includes identifying flight control instructions to pilot the UAV according to a navigational algorithm and transmitting the flight control instructions to the UAV. Fight control instructions may be transmitted to the UAV from a navigation computer installed in a remote control device or may be transmitted to the UAV from a navigational computer installed on the UAV. Exemplary navigational algorithms are discussed above with reference to FIGS. 6-15 and such exemplary navigational algorithms, as well as others, are available for use with the method of FIG. 16. While piloting the UAV, the method of FIG. 16 includes reading (418) from the GPS receiver a sequence of GPS data representing a flight of the UAV and anticipating (419) a future position of the UAV on the anticipated course. Anticipating (419) a future position of the UAV on the anticipated course is typically carried out by applying a formula to the current position of the UAV to anticipate one or more coordinates on an anticipated course to the destination waypoint. Anticipating (419) a future position of the UAV on the flight path is typically carried out in dependence upon the current heading of the UAV, the current environmental factors such as for example the current wind vector, macros dictating the flight of the UAV, and other factors as will occur to those of skill in the art. The anticipated future position of the UAV may be as close to the current UAV position as a few inches or feet ahead of the UAV, or may be miles ahead of the UAV. The method of FIG. 16 also includes identifying (550) an obstacle (552) dependence upon the future position. One way of identifying (550) an obstacle (552) in dependence upon the future position is carried out by retrieving obstacle data describing potential obstacles from a database in dependence the future position. In such a database, obstacle information such as the location and dimensions of potential obstacles such as mountains, buildings, no-fly zones, and others are indexed by location. A UAV retrieves obstacle data describing the dimensions of a potential obstacle from the database in dependence upon the anticipated future position of the UAV and if the dimensions of the potential obstacle would disrupt the flight of the UAV, the potential obstacle is identified as an obstacle to be avoided by the method of FIG. 16. Three-dimensional graphics are not only useful in depicting the flight of a UAV as described above, but such graphics are also useful in identifying and avoiding obstacles that would otherwise disrupt the flight of the UAV. Another way of identifying (550) an obstacle (552) therefore includes depicting (420) an anticipated flight of the UAV (100) with 3D computer graphics in dependence upon the future position of the UAV and identifying (550) an obstacle (552) in dependence upon the depiction of the anticipated flight. Depicting (420) an anticipated flight of the UAV (100) with 3D computer graphics may be carried out using the visualization graphics such as DarkBasic, OpenGL, DirectX, Direct3D, and others as will occur to those of skill in the art discussed above. Such a graphic depiction of the anticipated flight path often includes coalescing satellite images, with data describing potential obstacles. The 3D graphics may be displayed or may be left unrendered for analysis to identify an obstacle. That is, the 3D graphics do not have to be displayed to be useful in identifying an obstacle. Identifying (550) an obstacle (552) on the anticipated course of the UAV (100) in dependence upon the depiction of the anticipated flight path may be carried out identifying an obstacle from unrendered three dimensional depiction such as by scanning the unrendered depiction for descriptions of obstacles. Alternatively, identifying (550) an obstacle (552) in the anticipated course of the UAV (100) in dependence upon the depiction of the anticipated flight may also be carried out by rendering and displaying the anticipated flight and analyzing the displayed depiction of the flight. Image recognition software may be used to compare objects in the displayed depiction of the anticipated flight with image models in a database for identification of obstacles. One example of image recognition software capable of modification for use in the method of FIG. 16 is SNV Vision currently available from Spikenet Technology. After identifying an obstacle that would otherwise disrupt the flight of the UAV, the method of FIG. 16 includes selecting (556) an obstacle avoidance algorithm (554) and piloting (558) the UAV (100) in accordance with an obstacle avoidance algorithm. Identifying (550) an obstacle (552) on the anticipated course of the UAV (100) in dependence upon the depiction of the anticipated flight path may include identifying an algorithm useful in avoiding a two dimensional geographic area such as a no-fly zone. For further explanation, FIG. 17 sets forth a flow chart illustrating an exemplary method of piloting the UAV in accordance with an obstacle avoidance algorithm to avoid a no-fly zone. The method of FIG. 17 includes identifying (560) an intermediate waypoint (562) and flying (564) past the intermediate waypoint (562). One way of identifying (560) an intermediate waypoint (562) includes selecting a coordinate outside the no-fly zone. One way of selecting a coordinate outside the no-fly zone includes defining a bracket line running through the no-fly zone and then selecting a coordinate on the bracket line that is not within the no fly zone. A bracket line is a range of latitudes or longitudes that defines a line useful in selecting intermediate waypoints according to embodiments of the present invention. The method of FIG. 17 also includes identifying (566) a second intermediate waypoint (568) on the originally anticipated flight course and flying (570) past the second intermediate waypoint (568). Identifying (566) a second intermediate waypoint (568) on the originally anticipated flight course advantageously returns the UAV to the course originally planned for the UAV absent identification of the obstacle. The method of FIG. 17 includes calculating (572) a new heading to the original destination waypoint and piloting (574) on the new heading in accordance with a navigational algorithm. In many examples of the method of FIG. 17, the navigational algorithm for use in piloting on the new heading is the same navigational algorithm previously in use prior to deviating from the original flight path to avoid the obstacle. For further explanation, FIG. 18 sets forth a line drawing illustrating the flight path of a UAV implementing the method of FIG. 17. In the example of FIG. 18 an intermediate waypoint (582) is located outside of the no-fly zone (580) and resides on a bracket line (584) that passes through the no fly zone (580). The second intermediate waypoint (584) resides on the original anticipated course (578) between the starting point (576) and the destination waypoint (588). In the example of FIG. 18, to avoid the no-fly zone (580) the UAV flies past the intermediate waypoint (582), calculates a new heading toward the second intermediate waypoint (58.4) flies past the second intermediate waypoint (584), calculates a new heading toward the destination waypoint (588) and pilots to the destination waypoint (588) in accordance with a navigational algorithm. The example of FIG. 18 results in an actual flight path (586) that avoids the no fly zone and the returns to flying on the original anticipated course (578). The example of FIG. 18 results in a flight path that returns to the originally anticipated course. In some situations, it may be inefficient to return to the originally anticipated course. For further explanation, FIG. 19 sets forth a flow chart illustrating another exemplary method of piloting the UAV in accordance with an obstacle avoidance algorithm that does not return to the originally anticipated course. The method of FIG. 19 includes identifying (590) an intermediate waypoint (592) and flying (594) past the intermediate waypoint. One way of identifying (590) an intermediate waypoint (592) typically includes selecting a coordinate outside the no-fly zone. One way of selecting a coordinate is to define a bracket line running through the no-fly zone and then selecting a coordinate on the bracket line that is not within the no fly zone. The method of FIG. 19 also includes calculating (596) a new heading to an original waypoint and piloting (598) on the new heading in accordance with a navigational algorithm. Examples of calculating headings and piloting in accordance with navigational algorithms are discussed above with reference to FIGS. 6-15. The inclusion of these examples of calculating headings and piloting in accordance with navigational algorithms is for explanation and not for limitation. All ways of calculating a new heading to an original waypoint and piloting on the new heading in accordance with a navigational algorithm are within the scope of the present invention. For further explanation, FIG. 20 is a line drawing illustrating the flight path of a UAV implementing the method of FIG. 19. In the example of FIG. 20, an intermediate waypoint (582) is located outside of the no-fly zone (580) and resides on a bracket line (584) that passes through the no fly zone (580). In the example of FIG. 20, to avoid the no-fly zone (580) the UAV flies past the intermediate waypoint (582), calculates a new heading toward the destination waypoint (588) and pilots to the destination waypoint in accordance with a navigational algorithm. The example of FIG. 18 results in an actual flight path (586) that does not return to the originally anticipated course (578). In many embodiments, identifying an obstacle in the anticipated flight path of the UAV in dependence upon the depiction of the anticipated flight path includes identifying an object having a height greater than a current altitude of the UAV. One way of piloting the UAV in accordance with an obstacle avoidance algorithm for avoiding an object having a height greater than the current altitude of the UAV includes determining an new altitude greater than the height of the obstacle and piloting the UAV at the new altitude. Piloting the UAV at the new altitude includes determining a rate of increase in altitude that is results in adequately increasing the altitude of the UAV such that the altitude of the UAV is greater than the height of the obstacle before the UAV reaches the obstacle. It will be understood from the foregoing description that modifications and changes may be made in various embodiments of the present invention without departing from its true spirit. The descriptions in this specification are for purposes of illustration only and are not to be construed in a limiting sense. The scope of the present invention is limited only by the language of the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The field of the invention is data processing, or, more specifically, methods, systems, and products for navigating a UAV with obstacle avoidance algorithms. 2. Description of Related Art Many forms of UAV are available in prior art, both domestically and internationally. Their payload weight carrying capability, their accommodations (volume, environment), their mission profiles (altitude, range, duration), and their command, control and data acquisition capabilities vary significantly. Routine civil access to these various UAV assets is in an embryonic state. Conventional UAVs are typically manually controlled by an operator who may view aspects of a UAV's flight using cameras installed on the UAV with images provided through downlink telemetry. Navigating such UAVs from a starting position to one or more waypoints requires an operator to have specific knowledge of the UAV's flight, including such aspects as starting location, the UAV's current location, waypoint locations, and so on. Operators of prior art UAVs usually are required generally to manually control the UAV from a starting position to a waypoint with little aid from automation. There is therefore an ongoing need for improvement in the area of UAV navigations. | <SOH> SUMMARY OF THE INVENTION <EOH>Methods, systems, and computer program products are provided for navigating a UAV that include piloting the UAV, under control of a navigation computer, in accordance with a navigation algorithm. While piloting the UAV, embodiments include reading from the GPS receiver a sequence of GPS data, anticipating a future position of the UAV, identifying an obstacle in dependence upon the future position, selecting an obstacle avoidance algorithm, and piloting the UAV in accordance with an obstacle avoidance algorithm. Identifying an obstacle in dependence upon the future position may include comprises retrieving obstacle data from a database in dependence the future position. Identifying an obstacle in dependence upon the future position may also include depicting an anticipated flight of the UAV with 3D computer graphics in dependence upon the future position and identifying an obstacle in dependence upon the depiction of the anticipated flight. Piloting the UAV in accordance with an obstacle avoidance algorithm may include identifying an intermediate waypoint, flying past the intermediate waypoint, identifying a second intermediate waypoint on an originally anticipated course, flying past the second intermediate waypoint, calculating a new heading to an original destination waypoint, and piloting on the new heading in accordance with a navigational algorithm. Piloting the UAV in accordance with an obstacle avoidance algorithm may also include identifying an intermediate waypoint, flying past the intermediate waypoint, calculating a new heading to an original destination waypoint, and piloting on the new heading in accordance with a navigational algorithm. Piloting the UAV in accordance with an obstacle avoidance algorithm may also include determining a new altitude greater than the height of the identified obstacle and piloting the UAV at the new altitude. The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular descriptions of exemplary embodiments of the invention as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts of exemplary embodiments of the invention. | 20050124 | 20070605 | 20070510 | 62904.0 | G01C2300 | 2 | ZANELLI, MICHAEL J | NAVIGATING A UAV WITH OBSTACLE AVOIDANCE ALGORITHMS | UNDISCOUNTED | 0 | ACCEPTED | G01C | 2,005 |
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11,041,840 | ACCEPTED | Overhead door locking operator with remote light assembly | A system for raising and lowering a sectional overhead door between an open position and a closed position including, a counterbalance system adapted to be connected to the door, an operator motor assembly mounted proximate to the sectional overhead door in the closed position of the sectional overhead door, at least a portion of the operator motor assembly movable between a door operating position and a door locking position, and a locking assembly (370) having an engaged position to hold the motor assembly in the operating position and a disengaged position to release the motor assembly allowing it to move to the door locking position. The system may be provided with a remote light assembly having a switchable light source in sensing communication with the operator motor such that operation of the motor activates the light source. The system is further provided with a handle assembly (515) operatively engaging the motor assembly (40) and counterbalance system (30) to selectively disconnect the motor assembly (40) from the counterbalance system (30), whereby urging of a rotatable handle (516) to a disconnect position (516′) allows the door (D) to be manually freely moveable with the aid of the counterbalance system (30). | 1-28. (canceled) 29. An overhead door operating system comprising: an operator motor selectively opening or closing the door; a transmitter activated upon an operating cycle of said operator motor and transmitting a signal; and a remote assembly controlled by said signal. 30. The operating system according to claim 29, wherein said remote assembly comprises a light source. 31. The operating system according to claim 29, wherein said signal is a radio frequency signal. 32. The operating system according to claim 29, wherein said signal is an infrared signal. 33. The overhead door operating system according to claim 29, wherein said remote assembly comprises: a light source; and a sensing element connected to said light source, said sensing element receiving said signal and controlling illumination of said light source. 34. The overhead door operating system according to claim 33, wherein said signal is one of a radio frequency signal and an infrared signal. 35. The overhead door operating system according to claim 34, wherein said light source is illuminated for a period of time after said operator motor has stopped. 36. The overhead door operating system according to claim 33, wherein said remote assembly further comprises a receiver assembly which carries said sensing element, and wherein said receiver assembly is pivotable and rotatable for reception of said signal. | CROSS-REFERENCE TO RELATED APPLICATION This application is a divisional of U.S. Ser. No. 09/710,071 filed on Nov. 10, 2000, which is a continuation-in-part of U.S. Ser. No. 09/548,191 filed Apr. 13, 2000. TECHNICAL FIELD The present invention relates generally to operators for sectional overhead doors. More particularly, the present invention relates to a type of “jack-shaft” operator for manipulating a sectional overhead door between the open and closed positions. More specifically, the present invention relates to a jack-shaft operator for a sectional overhead door which is highly compact, operates to lock the door in the closed position, and has a mechanical disconnect. BACKGROUND ART Motorized apparatus for opening and closing sectional overhead doors have long been known in the art. These powered door operators were developed in part due to extremely large, heavy commercial doors for industrial buildings, warehouses, and the like where opening and closing of the doors essentially mandates power assistance. Later, homeowners' demands for the convenience and safety of door operators resulted in an extremely large market for powered door operators for residential usage. The vast majority of motorized operators for residential garage doors employ a trolley-type system that applies force to a section of the door for powering it between the open and closed positions. Another type of motorized operator is known as a “jack-shaft” operator, which is used virtually exclusively in commercial applications and is so named by virtue of similarities with transmission devices where the power or drive shaft is parallel to the driven shaft, with the transfer of power occurring mechanically, as by gears, belts, or chains between the drive shaft and a driven shaft, normally part of the door counterbalance system, controlling door position. While some efforts have been made to configure hydraulically or pneumatically-driven operators, such efforts have not achieved any substantial extent of commercial acceptance. The well-known trolley-type door operators are attached to the ceiling and connected directly to the top section of a garage door and for universal application may be powered to operate doors of vastly different size and weight, even with little or no assistance from a counterbalance system for the door. Since the operating force capability of trolley-type operators is normally very high, force adjustments are normally necessary and provided to allow for varying conditions and to allow the operator to be adjusted for reversing force sensitivity, depending on the application. When a garage door and trolley-type operator are initially installed and both adjusted for optimum performance, the overhead door system can perform well as designed. However, as the system ages, additional friction develops in door and operator components due to loss of lubrication at rollers and hinges. Also, the door can absorb moisture and become heavier, and counterbalance springs can lose some of their original torsional force. These and similar factors can significantly alter the operating characteristics seen by the operator, which may produce erratic door operation such as stops and reversals of the door at unprogrammed locations in the operating cycle. Rather than ascertaining and correcting the conditions affecting door performance, which is likely beyond a homeowner's capability, or engaging a qualified service person, homeowners frequently increase the force adjustment to the maximum setting. However, setting an operator on a maximum force adjustment creates an unsafe condition in that the operator becomes highly insensitive to obstructions. In the event a maximum force setting is effected on a trolley-type operator, the unsafe condition may also be dramatically exemplified in the event of a broken spring or springs. In such case, if the operator is disconnected from the door in the fully open position during an emergency or if faulty door operation is being investigated, one half or all of the uncounterbalanced weight of the door may propel the door to the closed position with a guillotine-like effect. Another problem with trolley-type door operators is that they do not have a mechanism for automatically disengaging the drive system from the door if the door encounters an obstruction. This necessitates the considerable effort and cost which has been put into developing a variety of ways, such as sensors and encoders, to signal the operator controls when an obstruction is encountered. In virtually all instances, manual disconnect mechanisms between the door and operator are required to make it possible to operate the door manually in the case of power failures or fire and emergency situations where entrapment occurs and the door needs to be disconnected from the operator to free an obstruction. These mechanical disconnects, when coupled with a maximum force setting adjustment of the operator, can readily exert a force on a person or object which may be sufficiently high to bind the disconnect mechanism and render it difficult, if not impossible, to actuate. In addition to the serious operational deficiencies noted above, manual disconnects, which are normally a rope with a handle, must extend within six feet of the floor to permit grasping and actuation by a person. In the case of a garage opening for a single car, the centrally-located manual disconnect rope and handle, in being positioned medially, can catch on a vehicle during door movement or be difficult to reach due to its positioning over a vehicle located in the garage. Trolley-type door operators raise a host of peripheral problems due to the necessity for mounting the operator to the ceiling or other structure substantially medially of and to the rear of the sectional door in the fully open position. Operationally, trolley-type operators are susceptible to other difficulties due to their basic mode of interrelation with a sectional door. Problems are frequently encountered by way of misalignment and damage because the connecting arm of the operator is attached directly to the door for force transmission, totally independent of the counterbalance system. Another source of problems is the necessity for a precise, secure mounting of the motor and trolley rails which may not be optimally available in many garage structures. Thus, trolley-type operators, although widely used, do possess certain disadvantageous and, in certain instances, even dangerous characteristics. The usage of jack-shaft operators has been limited virtually exclusively to commercial building applications where a large portion of the door stays in the vertical position. This occurs where a door opening may be 15, 20, or more feet in height, with only a portion of the opening being required for the ingress and egress of vehicles. These jack-shaft operators are not attached to the door but attach to a component of the counterbalance system, such as the shaft or a cable drum. Due to this type of connection to the counterbalance system, these operators require that a substantial door weight be maintained on the suspension system, as is the case where a main portion of the door is always in a vertical position. This is necessary because jack-shaft operators characteristically only drive or lift the door from the closed to the open position and rely on the weight of the door to move the door from the open to the closed position, with the suspension cables attached to the counterbalance system controlling only the closing rate. Such a one-way drive in a jack-shaft operator produces potential problems if the door binds or encounters an obstruction upon downward movement. In such case, the operator may continue to unload the suspension cables, such that if the door is subsequently freed or the obstruction is removed, the door is able to free-fall, with the potential of damage to the door or anything in its path. Such unloading of the suspension cables can also result in the cables coming off the cable storage drums, thus requiring substantial servicing before normal operation can be resumed. Jack-shaft operators are normally mounted outside the tracks and may be firmly attached to a doorjamb rather than suspended from the ceiling or wall above the header. While there is normally ample jamb space to the sides of a door or above the header in a commercial installation, these areas frequently have only limited space in residential garage applications. Further, the fact that normal jack-shaft operators require much of the door to be maintained in a vertical position absolutely mitigates against their use in residential applications where the door must be capable of assuming essentially a horizontal position since, in many instances, substantially the entire height of the door opening is required for vehicle clearance during ingress and egress. In order to permit manual operation of a sectional door in certain circumstances, such as the loss of electrical power, provision must be made for disconnecting the operator from the drive shaft. In most instances this disconnect function is effected by physically moving the drive gear of the motor out of engagement with a driven gear associated with the drive shaft. Providing for such gear separation normally results in a complex, oversized gear design which is not compatible with providing a compact operator which can feasibly be located between the drive shaft for the counterbalance system and the door. Larger units to accommodate gear design have conventionally required installation at or near the end of the drive shaft which may result in shaft deflection that can cause one of the two cables interconnecting the counterbalance drums and the door to carry a disproportionate share of the weight of the door. Another common problem associated particularly with jack-shaft operators is the tendency to generate excessive objectionable noise. In general, the more components, and the larger the components, employed in power transmission the greater the noise level. Common operator designs employing chain drives and high speed motors with spur gear reducers are notorious for creating high noise levels. While some prior art operators have employed vibration dampers and other noise reduction devices, most are only partially successful and add undesirable cost to the operator. Another requirement in jack-shaft operators is mechanism to effect locking of the door when it is in the closed position. Various types of levers, bars and the like have been provided in the prior art which are mounted on the door or on the adjacent track or jamb and interact to lock the door in the closed position. In addition to the locking mechanism which is separate from the operator there is normally an actuator which senses slack in the lift cables which is caused by a raising of the door without the operator running, as in an unauthorized entry, and activates the locking mechanism. Besides adding operational complexity, such locking mechanisms are unreliable and, also, introduce an additional undesirable cost to the operator system. DISCLOSURE OF THE INVENTION Therefore, an object of the present invention is to provide a motorized operator for a sectional door wherein a component of the operator is positioned proximate to the door to effect a locking function when the door reaches the closed position. Another object of the present invention is to provide such a motorized operator wherein the motor pivots into contact with the door to effect locking of the door in the closed position. A further object of the present invention is to provide such a motorized operator wherein a worm output of the motor and a driven worm wheel attached to the drive tube of a counterbalancing system remain in operative contact throughout the door operating cycle, thereby permitting the utilization of reduced size gears and permitting a smaller operator package. Still another object of the present invention is to provide such a motorized operator which does not require a locking mechanism or actuator therefore as components separate from the operator itself. Another object of the present invention is to provide a motorized operator for sectional doors that has a disconnect that may be manually actuated from a location remote from the operator. A further object of the present invention is to provide such a motorized operator wherein actuation of the manual disconnect accomplishes both the separation of the operator from the counterbalance system and the unlocking of the door, whereby the door may be manually lifted from the closed position with assistance of the counterbalance system. A further object of the invention is to provide such an operator wherein the manual disconnect does not disturb the meshed relationship interconnecting the operator motor and the remainder of the drive gear system. Another object of the present invention is to provide a motorized operator for sectional doors that eliminates the need for any physical attachment to the door in that it is mounted proximate to and operates through the counterbalance system and may be positioned at any location along the width of the door, preferably centrally thereof, in which case it could serve the dual purpose of a center support for the drive tube. A further object of the present invention is to provide such a motorized operator that may serve to reduce deflection of the counterbalance drive shaft to which it is directly coupled to provide prompt, direct feedback from any interruptions and obstructions which may effect the door during travel. Yet a further object of the invention is to provide such an operator which can be readily sized to fit within the area defined by the tracks at the sides of the door, the drive tube or drive shaft of the counterbalance system and the travel profile of the door, thereby requiring no more headroom or sideroom than a non-motorized door. Still another object of the invention is to provide such an operator which can be mounted in an area thus defined while moving between a non-interfering operating position and a locking position wherein a portion of the operator may physically engage the inner surface of the door proximate to the top. Still another object of the present invention is to provide such a motorized operator wherein a portion of the operator acts as a stop to movement of the top of the door relative to the header to create resistence to forced entry, air infiltration, water infiltration, and forces created by wind velocity pressure acting on the outside of the door. Still another object of the present invention is to provide a motorized operator for sectional doors that does not require trolley rails, bracing for drive components, or any elements suspended from the ceiling or above the header or otherwise outside the area defined by the tracks, the counterbalance system and the door operating path. Yet another object of the present invention is to provide such an operator wherein the number of component parts is greatly reduced from conventional operators such as to provide improved reliability and quicker and easier installation. Yet another object of the invention is to provide such an operator which has fewer component parts subject to wear, requires less maintenance, achieves a longer operating life, while achieving quieter operation and less vibration due to a reduction in the number and size of rotating and other drive components. In general, the present invention contemplates an operator for moving in upward and downward directions a sectional door having a counterbalancing system with a drive tube interconnected with the door including, a reversible motor, a drive gear selectively driven in two directions by the motor, a driven gear freely rotatably mounted on the drive tube and engaging the drive gear, a slide guide non-rotatably mounted on the drive tube, a disconnect mounted on the slide guide and selectively movable between a first position rotatably connecting the driven gear and the slide guide and a second position disconnecting the drive gear and the slide guide, and an actuator for selectively moving the disconnect between the first position and the second position. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a rear perspective view of a sectional overhead garage door installation showing a motorized operator and remote light assembly according to the concepts of the present invention installed in operative relation thereto, with the operator depicted in its operating position in solid lines and the door locking position in chain lines and further schematically depicting transmission of a signal from the operator to the remote light assembly. FIG. 2 is an enlarged perspective view of the motorized operator of FIG. 1 with the cover removed and portions broken away to show the mechanical interconnection of the motorized operator with the drive tube of the counterbalancing system. FIG. 3 is a further enlarged exploded perspective view showing details of the drive system and the disconnect assembly. FIG. 4 is a further enlarged perspective view of the motorized operator of FIG. 1 with portions of the cover broken away to show additional details of the drive elements and the disconnect assembly. FIG. 5 is an exploded perspective view showing details of operative components of the retaining assembly which selectively secures the operator in the door operating position. FIG. 6 is an enlarged fragmentary portion of the sectional overhead door installation of FIG. 1 showing details of the placement and structure of the manual disconnect assembly. FIG. 7 is an enlarged exploded perspective view showing details of an alternate embodiment of drive tube drive assembly according to the concepts of the present invention. FIG. 8 is a perspective view of the motorized operator of the alternate embodiment of FIG. 7 with the gear removed to show the mechanical interconnection of the motorized operator with the drive tube of the counterbalancing system in the assembled configuration. FIG. 9 is a perspective view of a motorized operator system having a modified form of locking assembly. FIG. 10 is an exploded perspective view showing details of the locking assembly of FIG. 9 including a biasing member and an alternate form of biasing member. FIG. 11 is a sectional view of the modified form of locking assembly taken substantially along the line 11-11 of FIG. 9 showing details of the biasing member having moved the disconnect rod to engage the motor assembly. FIG. 12 is a sectional view similar to FIG. 11 showing the locking rod out of engagement with the motor assembly preparatory to pivoting the motor to lock the door. FIG. 13 is an enlarged fragmentary portion of the sectional overhead door installation of FIG. 1 shown from behind the door outwardly and showing details of the structure of an alternative handle assembly in a manual disconnect assembly. FIG. 14 is an enlarged fragmentary portion similar to FIG. 13 with the handle assembly moved to disconnect the motor assembly from the counterbalance system. FIG. 15 is an enlarged fragmentary portion similar to FIG. 13 viewed from outside the door inwardly to show additional details of the handle assembly. FIG. 16 is an enlarged fragmentary portion of the remote light assembly shown in FIG. 1 having a receiver assembly depicted in a receiving position. FIG. 17 is an enlarged fragmentary portion similar to FIG. 16 with the receiver assembly depicted in a stowed position in solid lines and a signal receiving position in chain lines. PREFERRED EMBODIMENT FOR CARRYING OUT THE INVENTION A motorized operator system according to the concepts of the present invention is generally indicated by the numeral 10 in the drawing figures. The operator system 10 is shown in FIG. 1 mounted in conjunction with a sectional door D of a type commonly employed in garages for residential housing. The opening in which the door D is positioned for opening and closing movements relative thereto is defined by a frame, generally indicated by the numeral 12, which consists of a pair of spaced jambs 13, 14 that, as seen in FIG. 1, are generally parallel and extend vertically upwardly from the floor (not shown). The jambs 13, 14 are spaced and joined at their vertically upper extremity by a header 15 to thereby delineate a generally inverted U-shaped frame 12 around the opening for the door D. The frame 12 is normally constructed of lumber, as is well known to persons skilled in the art, for purposes of reinforcement and facilitating the attachment of elements supporting and controlling door D, including the operator system 10. Affixed to the jambs 13, 14 proximate the upper extremities thereof and the lateral extremities of the header 15 to either side of the door D are flag angles, generally indicated by the numeral 20. The flag angles 20 generally consist of L-shaped vertical members 21 having a leg 22 attached to an underlying jamb 13, 14 and a projecting leg 23 preferably disposed substantially perpendicular to the leg 22 and, therefore, perpendicular to the jambs 13, 14 (See FIG. 6). Flag angles 20 also include an angle iron 25 positioned in supporting relation to tracks T, T located to either side of door D. The tracks T, T provide a guide system for rollers attached to the side of door D, as is well known to persons skilled in the art. The angle irons 25 normally extend substantially perpendicular to the jambs 13, 14 and may be attached to the transitional portion of tracks T, T between the vertical section and the horizontal section thereof or in the horizontal section of tracks T, T. The tracks T, T define the travel of the door D in moving upwardly from the closed to open position and downwardly from the open to closed position. The operator system 10 may be electrically interconnected with a ceiling unit, which may contain a power supply, a light, a radio receiver with antenna for remote actuation of operator system 10 in a manner known in the art, and other operational peripherals. The ceiling unit may be electrically interconnected with a wall unit having an up/down button, a light control, and controls for other known functions. Referring now to FIGS. 1 and 2 of the drawings, the operator system 10 mechanically interrelates with the door D through a counterbalance system, generally indicated by the numeral 30. As shown, the counterbalance system 30 includes an elongate drive tube 31 extending between tensioning assemblies 32, 32 positioned proximate each of the flag angles 20. While the exemplary counterbalance system 30 depicted herein is advantageously in accordance with U.S. Pat. No. 5,419,010, it will be appreciated by persons skilled in the art that operator system 10 could be employed with a variety of torsion-spring counterbalance systems. In any instance, the counterbalance system 30 includes cable drum mechanisms 33 positioned on the drive tube 31 proximate the ends thereof which rotate with drive tube 31. The cable drum mechanisms 33 each have a cable 34 reeved thereabout which is affixed to the door D preferably proximate the bottom, such that rotation of the cable drum mechanisms 33 operates to open or close the door D in conventional fashion. As seen in FIGS. 1 and 2, the operator system 10 has an operator housing 35 which may conveniently enclose a length of the drive tube 31. While drive tube 31 is depicted as a hollow tubular member that is non-circular in cross-section, it is to be appreciated that circular drive tubes, solid shafts, and other types of driving elements that rotate cable drums, such as cable drum mechanisms 33, may be employed in conjunction with the operator system 10 of the instant invention and are encompassed within this terminology in the context of this specification. The operator housing 35 has apertures 36 at either end through which drive tube 31 extends. Operator housing 35 has a mounting plate 37 that may be attached to the header 15 as by a plurality of cap screws 38 (FIG. 2). While operator housing 35 is shown mounted in relation to drive tube 31 substantially medially between the cable drum mechanisms 33, 33, it is to be noted that with the depicted counterbalance system 30, the operator housing 35 could be mounted at any desired location along drive tube 31 should it be necessary or desirable to avoid an overhead or wall obstruction in a particular garage design. Operatively, interrelated with the operator housing 35 is an operator motor assembly, generally indicated by the numeral 40. For purposes of powering the door D, the operator motor assembly 40 has an electric motor 41 constituting one of various types employed for overhead doors which is designed for stop, forward and reverse rotation of a motor shaft 42. As seen particularly in FIGS. 1, 2 and 4 the operator motor assembly 40 maybe provided with a motor cover 43. As shown, the motor cover 43 has a cylindrical portion 44 that overlies electric motor 41. Motor cover 43 may have an axial extension consisting of a truncated portion 45 of tapering dimensions terminating in an elongated oval portion 46 having flat parallel sides 47 and 48. The oval portion 46 of motor cover 43 has the flat side 47 positioned for engagement with the top of the top panel P of the door D when the operator motor assembly 40 is in the door locked position depicted in chain lines as 45 in FIG. 1. The wide, flat surface 47 may be advantageous in providing an enlarged contact area for locking engagement with the top of panel P to urge the panel P into contact with the header 15 to effect sealing engagement of panel P with the door frame 12. In the operating position of operator motor assembly 40 depicted in FIG. 1, the motor cover 43 extends only slightly above drive tube 31 and is essentially horizontally aligned with cable drum mechanisms 33, 33 and tensioning assemblies 32, 32 such as to remain vertically as well as laterally within the confines of the counterbalance system 30. Referring particularly to FIGS. 3 and 4, a drive train enclosure, generally indicated by the numeral 50, projects from the motor cover 43 in the direction opposite the truncated portion 45 thereof. The drive train enclosure 50 has a hollow cylindrical extension portion 51 which extends from motor cover 43. The cylindrical portion 51 of drive train enclosure 50 accommodates a worm 52 which is attached to or may be cut into the shaft 42 of motor 41. The drive train enclosure 50 also includes an open-ended cylindrical journal 53 which intercommunicates through the wall thereof with the interior of cylindrical portion 51 of drive train enclosure 50 and particularly with the worm 52 reposing therein. As best seen in FIGS. 3 and 4, the journal 53 seats internally thereof a worm wheel 54 which is at all times positioned in mating engagement with the worm 52 of electric motor 41. The drive tube 31 of counterbalance system 30 is selectively rotationally driven by motor 41 through a drive tube drive assembly, generally indicated by the numeral 55. The drive tube drive assembly 55 includes a slide guide, generally indicated by the numeral 56, which is a generally elongate, cylindrical member that has a substantially circular outer surface 57 that freely rotatably mounts the worm wheel 54 positioned within the drive train enclosure 50. The slide guide 56 has internal surfaces 58 that are non-circular and, in cross section, substantially match the out of round configuration of the drive tube 31. Thus, the slide guide 56 and drive tube 31 are non-rotatably interrelated, such that drive tube 31 moves rotationally with slide guide 56 at all times. The slide guide 56 is maintained at a fixed position axially of the drive tube 31 by interengagement with the drive train enclosure 50 and worm wheel 54. Proximate the axial extremity of the circular outer surface 57 of slide guide 56 are a plurality of spring catches 59. As shown, there are four spring catches 59, which are equally spaced about the outer periphery of the outer surface 57 of slide guide 56. When the slide guide 56 is positioned inside worm wheel 54, the spring catches 59 abut the axial surface 60 of the worm wheel 54. The drive tube drive assembly 55 also includes an end cap 61 that interfits within the cylindrical journal 53 of the drive train enclosure, as best seen in FIG. 4. Thus, the spring catches 59 of slide guide 56 are interposed between and thus axially restrained by axial surface 60 of worm wheel 54 and the end cap 61. Movement of the worm wheel 54 in an axial direction opposite the end cap 61 is precluded by a radially in-turned flange 62 in the cylindrical journal 53 of drive train enclosure 50. The end cap 61 has a radial inner rim 63 that serves as a bearing surface for the axially outer surface of circular outer surface 57 of slide guide 56 that extends axially beyond the spring catches 59 (see FIGS. 3 and 4). The circular outer surface 57 of slide guide 56 has circumferentially-spaced, axial-extending grooves 65 for a purpose to be detailed hereinafter. The axial extremity of slide guide 56 opposite the axial outer surfaces 64 may be provided with encoder notches 66 to generate encoder signals representative of door position and movement for door control system functions of a type known to persons skilled in the art. Drive tube drive assembly 55 has a disconnect sleeve, generally indicated by the numeral 70, which is non-rotatably mounted on, but slidable axially of, the slide guide 56. As best seen in FIG. 3, the disconnect sleeve 70 has a generally cylindrical inner surface 71 that is adapted to slidingly engage the circular outer surface 57 of slide guide 56. The inner surface 71 has one or more tabs 72 that are inwardly raised, axially-extending surfaces, which are adapted to matingly engage the axially-extending grooves 65 of slide guide 56. Thus, when disconnect sleeve 70 is mounted on slide guide 56, with tabs 72 engaging the grooves 65, the disconnect sleeve 70 is free to slide axially of slide guide 56 but is precluded from relative rotation. The axially extremity of disconnect sleeve 70, which faces the worm wheel 54 has a plurality of circumferentially-spaced, projecting teeth 73, as seen in FIGS. 2 and 3. The teeth 73 selectively engage and disengage spaced circumferential recesses 74 in the axial extremity of worm wheel 54 opposite the axial surface 60. The selective engagement and disengagement of the disconnect sleeve 70 with the worm wheel 54 is controlled by a disconnect actuator, generally indicated by the numeral 80. The disconnect actuator 80 has a disconnect bracket, generally indicated by the numeral 81. The disconnect bracket 81 is generally L-shaped, with a triangular projection 82 that has a ring-shaped receiver 83 that seats the disconnect sleeve 70. The disconnect sleeve 70 has circumferentially-spaced, radially-outwardly extending catches 84 that engage one axial side of ring-shaped receiver 83. The disconnect sleeve 70 also has a flange 85 at the axial extremity opposite the teeth 73 and catches 84, such as to maintain disconnect sleeve 73 axially affixed to receiver 83 but freely rotatable relative thereto. The disconnect bracket 81 has a right angle arm 86 relative to the triangular projection 82, which is movably affixed to the mounting plate 37 of operator housing 35. As best seen in FIG. 3, the arm 86 has a pair of spaced lateral slots 87 through which headed lugs 88 project to support the disconnect bracket 81 and limit its motion to an axial direction whereby the disconnect bracket 81 moves the disconnect sleeve 70 directly axially into and out of engagement with the worm wheel 54. The disconnect actuator 80 also has a disconnect plate 90 which overlies the disconnect bracket 81, as best seen in FIG. 2. The disconnect plate 90 has a downwardly and laterally oriented slot 91 which receives a headed lug 92 which is affixed to the arm 86 of disconnect bracket 81. It will thus be appreciated that the component of lateral movement affected by upward or downward displacement of disconnect plate 90 is transmitted via lug 92 to lateral motion of the disconnect bracket 81 on lugs 88 to axially displace disconnect sleeve 70 in and out of engagement with worm wheel 54. Still referring to FIG. 2, the vertical movement of disconnect plate 90 of disconnect actuator 50 to move disconnect sleeve 70 from the engaged position depicted upwardly as indicated by the arrows toward the disengage position is effected by a cable C. The disconnect plate 90 has a guide loop 95 which slidably engages the cable C. The disconnect plate 90 has a projecting arm 96 to which one end of a tension spring 97 is connected. The other end of tension spring 97 is attached to a fixed tab 98 which, as shown, may be formed in the mounting plate 37 of operator housing 35. It is to be appreciated that the spring 97 eliminates any slack in the cable C while biasing disconnect plate 90 downwardly as viewed in FIG. 2 to continually urge the disconnect sleeve 70 toward engagement with worm wheel 54. The cable C is positioned to permit adjustment upon vertical movement of guide loop 95 by a pair of cable guides 100 which may be attached to or, as shown, formed from mounting plate 37 of operator housing 35. One run of cable C is directed to a further cable guide 101 and around a pivot pin 102 which affects a redirection toward the operator motor assembly 40. The cylindrical portion of 44 of motor cover 43 has a bifurcated hook 103 which retains an end pin 104 on the end of cable C. The other run of cable C extends through an aperture 110 in mounting plate 37 of operator housing 35 (FIG. 2). Referring to FIGS. 1 and 6, the cable C is routed over a tensioning assembly 32 of counterbalance system 30 to a handle assembly, generally indicated by the numeral 115. The handle assembly 115 includes a T-shaped handle 116 which terminates the cable C. Handle assembly 115 also includes a U-shaped plate 117 having a base 118 which may be affixed to a door jamb 13 as by a cap screw 119, or other suitable fastener, at a location which is convenient for disconnecting the door but sufficiently displaced from windows in the door D or in the garage structure to preclude actuation of the handle 116 by a potential intruder outside the garage. Handle 116 may further be located to facilitate its operation when a vehicle or other articles centrally within the garage or to otherwise prevent the handle 115 from damaging, interfering, or becoming entangled with articles within the garage. The U-shaped plate 117 has an outwardly projecting arm 120 with a bore 121 sized to freely receive the cable C but serving as a stop for T-shaped handle 116 with the cable tensioned and the disconnect actuator 80 in the position depicted in FIG. 2 with the disconnect sleeve 70 engaging the worm wheel 54. U-shaped plate 117 has a second projecting arm 122 having a V-shaped slot 123 therein. As seen in FIG. 6 the T-shaped handle 116 may be pulled downwardly to reside in a second position 116′ with the cable inserted in V-shaped slot 123. At such time, the operator motor assembly 40 is in the operate position, i.e. substantially perpendicular to the door D, and the disconnect actuator 80 is moved to the disengage position where the disconnect sleeve 70 is out of engagement with the worm wheel 54. Thus, in the second position of T-shaped handle 116′, the operator motor assembly 40 is in the operating position and the drive tube drive assembly 55 has disconnected the motor 41 and the drive tube 31, such that the door D can be freely manually raised or lowered as assisted by the counterbalance system 30. The run of cable C which extends out of the operator housing 35 may include an anti-intrusion member, generally indicated by the numeral 125. As best seen in FIG. 2 the anti-intrusion member consists of a cylindrical cable crimp 126 which is attached to the cable C. As can be seen in FIG. 2 the cable crimp 126 is positioned within the operator housing 35 and is spaced a short distance from aperture 110 when the disconnect actuator 80 is in the engaged position with the disconnect sleeve 70 in engagement with the worm wheel 54. If the handle assembly 115 is operated by pulling downwardly so that cable C proximate the aperture 110 is displaced directly axially, the cable crimp 126, which has a lesser diameter than the aperture 110, moves freely through the aperture 110 to affect the disconnect function. However, in the event of an attempted unauthorized entry, as through a window in the door D, a displacement of cable C by reaching inwardly and upwardly and pulling downwardly on the cable C will advance the cable C and cable crimp 126 other than directly axially, such that the cable crimp 126 will engage housing 35 in the area surrounding aperture 110 and thus preclude movement of the cable C sufficient to carry out a movement of the disconnect sleeve to a position where it is disengaged from worm wheel 54. The operator motor assembly 40 is selectively secured in the door operating position during the normal torque range attendant the moving of door D in upward and downward directions by a motor retaining assembly generally indicated by the numeral 130. As seen in FIGS. 3-5, the motor retaining assembly 130 includes a tubular projection extending from motor cover 43 and which may be adjacent to the drive train enclosure 50. Tubular projection 131 houses a plunger 132 which is biased outwardly of tubular projection 131 by a compression spring 133. The plunger 132 is maintained within tubular projection 131 and its axial throw therein is controlled by a slot 134 in the plunger 132 which receives a pin 135 extending through bores 136 in the tubular projection 131. The projecting extremity of plunger 152 has a flat contact surface 137 which terminates in a rounded extremity 138. The plunger 132 of motor retaining assembly 130 collectively operatively engages a fixed cylindrical stop 140. The stop 140 is mounted between a pair of friction washers 141 on a shaft 142 as is seen in detail in FIG. 5. The shaft 142 supporting cylindrical stop 140 is retained by a pair of spaced ears 143 having bores 144 supporting the shaft 142. As shown, the ears may be formed in the mounting plate 37 of operator housing 35. As may be appreciated from FIGS. 2, 4 and 5 of the drawings, the flat contact surface 137 of plunger 132 underlies the cylindrical stop 140 with the door in the operating position. The plunger 132 pivots away from the fixed cylindrical stop when the operator motor assembly 40 is in the locked position depicted in chain lines at 40′ in FIG. 1. When moving from the locked position to the operating position, the operator motor assembly 40 moves upwardly until the rounded extremity 138 of plunger 132 engages the cylindrical stop 40 which commences compression of the spring 133. When operator motor housing 40 reaches the operating position depicted at 40 in FIG. 1 in a position substantially perpendicular to the door D, the engaging surface 138 as urged by spring 133 rotates cylindrical stop 140 such that the flat contact surface 137 is positioned under the cylindrical stop 140. The flat contact surface 137 moves out from under roller 130 when sufficient torsional forces are placed upon operator motor assembly 40, thereby releasing from the motor retaining assembly 130. In instances of wider or heavier doors D, an alternative embodiment operator system 210 shown in FIGS. 7 and 8 maybe provided. Operator system 210 may have an operator motor assembly, generally indicated by the numeral 240, which may be essentially identical to the operator motor assembly 40. Operator system 210 also has a drive train enclosure, generally indicated by the numeral 250, which may be substantially similar to the drive train enclosure 50 and interact with a counterbalance system 30 and drive tube 31 constructed as described hereinabove. The differences in operator system 210 reside primarily in the drive tube drive assembly, generally indicated by the numeral 255. As best seen in FIG. 7, drive tube drive assembly 255 includes a slide guide, generally indicated by the numeral 256, which is a generally elongate cylindrical member that has a substantially circular outer surface 257 that freely rotatably mounts the worm wheel 254 positioned within the drive train enclosure 250. The slide guide 256 has internal surfaces 258 that are non-circular and, in cross section, substantially match the outer out-of-round configuration of the drive tube 31. Thus the slide guide 256 and drive tube 31 are non-rotatably interrelated, such that drive tube 31 moves rotationally with slide guide 256 at all times. The slide guide 256 is maintained in a fixed position axially of the drive tube 31 by interengagement with the drive train enclosure 250 and the worm wheel 254. The circular outer surface 257 of slide guide 256 has one or more spring catches 259 which extend outwardly of the outer surface 257. When the slide guide 256 is positioned inside worm wheel 254 within drive train enclosure 250 the spring catch 259 abuts the axially outer surface 260 of the worm wheel 254. An elongate bearing sleeve 261 having external threads 262 is threaded into internal threads 263 in the drive train enclosure 250. Once threaded into position, the bearing sleeve 261 receives the cylindrical extension 264 on slide guide 256. The cylindrical extension 264 may be provided with spaced circumferential grooves 265 which reduce contact area and thus friction between cylindrical extension 264 and bearing 261, while providing stabilization by contact over a substantial length. The extremity of bearing sleeve 261 opposite the threads 262 is supported in a bushing 266 as best seen in FIG. 7. A U-shaped wall support 267 having a groove 268 for receiving a flange 269 on bushing 266 maintains the bearing sleeve 261 in a fixed anchored position. A disconnect sleeve, generally indicated by the numeral 270 is structured and interacts with the slide guide 256 in the manner of the disconnect sleeve 70 described hereinabove. It will thus be appreciated that in operator system 210 the operator motor assembly 240 is supported to either side of drive train enclosure 250, i.e., through the disconnect sleeve 270 and the bearing sleeve 261. In the operation of both embodiments of the invention when the door D is closing the operator motor assembly 40 is in the operating position depicted in FIG. 1 with the disconnect sleeve 70 engaging the worm wheel 54 so that motor 41 is releasing cable 34 from the counterbalance system 30. At this time the motor retaining assembly 130 maintains the operator motor assembly 40 in the operating position. When the door D reaches the closed position the torque of motor 41 tends to rotate the operator motor assembly 40 about the drive tube 41 such that the rotational resistance provided by motor retaining assembly 130 is overcome, whereby the flat contact surface 137 of plunger 132 rotates away from the fixed cylindrical stop 140. Continued operation of motor 41 rotates the operator motor assembly 40 through approximately 90 degrees until the motor cover 43 engages the top panel P of the door D to thereby lock the door D in the closed position. The torsional resistance provided by the door D is sensed by controls of operator motor assembly 40 and operation of motor 41 is discontinued. In another embodiment of the invention a motorized operator is generally indicated by the numeral 300 in the figures. The operator system 300 shown in FIG. 9 is mounted in conjunction with a sectional door D (FIG. 1). Similar to the prior embodiments, operator system 300 may be electrically interconnected with a ceiling unit, which may contain a power supply, a light, a radio receiver with antenna for remote actuation of operator system 300 in a manner known in the art, and other operational peripherals. In further similarity to the prior embodiments, operator system 300 mechanically interrelates with the door D through a counterbalance system, generally indicated by the numeral 330. As previously described in other embodiments, the counterbalance system 330 includes an elongate drive tube 331 extending between tensioning assemblies positioned proximate each of the flag angles. As seen in FIG. 9, the operator system 300 has an operator housing 335 enclosing a length of the drive tube 331. The operator housing 335 has apertures 336, 336 (FIG. 10) at either end through which drive tube 331 extends. The operator housing 335 further has a mounting plate 337 that may be attached to the header as by a plurality of cap screws. Operatively, interrelated with the operator housing 335 is an operator motor assembly, generally indicated by the numeral 340. For purposes of powering the door D, the operator motor assembly 340 includes an electric motor designed for stop, forward, and reverse rotation of a motor shaft. The motor assembly 340 may be provided with a motor cover 343. In the operating position of operator motor assembly 340 depicted in FIG. 9, the motor cover 343 extends only slightly above drive tube 331 and is essentially horizontally aligned with cable drum mechanisms and tensioning assemblies such as to remain vertically as well as laterally within the confines of the counterbalance system 330. As previously described, if unrestrained, the torque developed by operation of motor assembly 340 tends to urge the motor assembly 340 toward a locked position similar to 40′ of FIG. 1, which potentially could cause the motor assembly 340 to interfere with the travel of the door D along its prescribed path. As discussed in previous embodiments, a motor restraining assembly, such as a latch, magnet or detent may be used to retain the motor assembly 340 in the operation position. Referring now to FIGS. 9-12, counterbalance assembly 331 has an alternative motor restraining assembly, generally indicated by the numeral 360, which may include a locking sleeve, generally indicated by the numeral 370, mounted on counterbalancing system 330 and located between housing 335 and motor assembly 340. As best seen in FIG. 10, the locking sleeve 370 has a generally cylindrical inner surface 371 that is adapted to receive the counterbalance tube 331. Locking sleeve 370 may be provided with at least one radially extending tab 372. The tabs 372 are located at one end 373 of the locking sleeve 370 and may be made to expand outwardly of aperture 336, when assembled, to axially fix the locking sleeve 370 relative to the housing 335. The outer surface 374 of locking sleeve 370 is provided with a plurality of threads 375. A locking actuator, generally indicated by the numeral 380, interrelates with the locking sleeve 370 to control release of motor assembly 340. The locking actuator 380 includes a locking cuff 381. As shown, the locking cuff 381 is a generally teardrop-shaped member, with a triangular projection 382 extending from a ring-shaped receiver 383 that receives the locking sleeve 370. The inner surface 384 of the ring-shaped receiver 383 has internal threads 385 which matingly engage the threaded outer surface 374 of locking sleeve 370. The locking cuff 381 seats between the housing 335 and the motor assembly 340. The triangular projection 382 of locking cuff 381 includes a cylindrical opening 386 axially aligned with a corresponding opening 387 on the motor assembly 340. An annular receiver 388 may be seated within opening 387 and provided with a collar 389. A locking rod, generally indicated by the numeral 390, is received in the openings 386, 387 and supported at one end 391 by the receiver 388 and/or a bracket 393 extending from housing 335 and at an opposite end 392 by the housing 335. The locking rod 390 is axially movable to selectively engage and disengage the motor assembly 340. Rod 390 may be provided with a collar 394 that projects radially of the outer surface 395 of rod 390 such that the opening 386 in triangular portion 382 of bracket 381 is slidable over an outer surface 395 of rod 390, but bracket 381 exerts an axial force on rod 390 upon contacting collar 394 causing selective axial displacement of locking rod 390. While collar 394 may be formed integrally with or attach directly to rod 390, collar 394 may be provided on a plug 396 that attaches to rod 390, for example by threads 397. To locate the rod 390 in a biased position (FIG. 11), in this case into engagement with opening 387 in motor housing 340, a biasing member, generally indicated by the numeral 400, operatively engages locking rod 390. Referring to FIG. 10, one embodiment of the biasing member 400 is shown as a coil spring 401 axially aligned with rod 390 and fitting over plug 396. In the embodiment shown, the collar 394 of plug 396 is located such that it is capable of contacting coil spring 401 on a first side 402 and locking cuff 381 on a second side 403. The coil spring 401 may be sized to allow axial movement of plug 396 through the bore 404 thereof and is interposed between the collar 394 and housing 335. Also, as shown in FIG. 9, the plug 396 may pass through an opening 406 formed in the housing 335. A lock ring 407 may then be fitted into a groove 408 of plug 396 to restrict axial movement of the rod 390. For example, in the embodiment shown in FIGS. 11 and 12, the lock ring 407 restricts the extent of entry of rod 390 into opening 387 in motor housing 340. In another embodiment, biasing member 400′ comprises a leaf spring 410 that biases rod 390 to an engaged position as described above. As shown in FIG. 10, leaf spring 410 may be located externally of housing 335 and attached thereto by a fastener 411. In accordance with this embodiment, collar 394′ is located outside of housing 335 and provided with a pair of axial notches 412, 412 that receive a pair of arms 413, 413 extending from body 414 of leaf spring 410. Arms 413 define a generally C-shaped opening 415 that receives a portion 416 of the end of collar 394′ between notches 412, 412. In this way collar 394′ is capable of contacting the spring 410 on a first side 402′ of the collar 394′ and the housing 335 on a second side 403′ of the collar 394′ causing collar 394′ to restrict the depth of entry of rod 390 into motor assembly 340. As in the coil spring embodiment, collar 394′ is attached or formed integrally with rod 390. Further, the collar 394′ may be located on a plug 396′ that is attachable to rod 390. Plug 396′ is moveable axially and penetrates housing 335 through opening 406. Plug 396′ extends radially of the outer surface 395 of rod 390. During operation of operator 300, the leaf spring 410 biases rod 390 into engagement with motor assembly 340. The rotation of locking sleeve 370 causes the cuff 381 to contact plug 396′ forcing the plug 396′ to move axially against the force of spring 410. Accordingly, rod 390 is axially displaced and is disengaged from or moved out of engagement with motor assembly 340. Upon reversal of the counterbalance system 330, biasing member 400′ drives rod 390 into engagement with motor assembly 340 to positively lock motor assembly 340 in the operating position. It will be appreciated that rod 390 may be similarly moved in and out of engagement with motor assembly 340 by directly coupling rod 390 to locking actuator 380 such that axial movement of actuator 380 causes axial movement of rod 390. During the normal operating cycle, the locking actuator 380 is positioned as shown in FIGS. 9 and 11 with the disconnect sleeve 370 engaging the counterbalance system 330. As elevation of the door D to an open position is commenced, locking rod 390 is biased into opening 387, as shown in FIG. 11, to positively lock the motor assembly 340 in the operating position. As shown, rotation of the locking sleeve 370 with the counterbalance tube 331 causes axial movement of locking actuator 380. As the door D is elevated, the motor assembly is held in operating position by the rod 390. At the end of the closing cycle, the locking actuator 380 causes axial movement of the rod 390 retracting 390 from the motor housing 340 (FIG. 12). At this point the torsional forces of the motor 341 cause the motor assembly 340 to rotate to a locked position, as described in the previous embodiments. An alternative handle assembly, shown in FIGS. 13-15 and generally indicated by the numeral 515, performs similarly to handle 115, previously described, selectively tensioning cable C to disconnect motor assembly 40 from counterbalance system 30. Handle assembly 515 includes a handle 516 and a bracket 517 receiving a portion of handle 516 having a plate 518 which may be affixed to a doorjamb 14 as by a cap screw or other suitable fastener. Handle assembly 515 is preferably placed at a location which is convenient for disconnecting the door D but sufficiently displaced from windows, in the door D or in the garage structure, to preclude actuation of the handle assembly 515 by a potential intruder outside the garage. Handle assembly 515 may further include a bolt 520 passing through bracket 517 and handle 516 attaching to plate 518 to provide a shaft about which handle 516 is freely rotatable to an operational position, where the motor assembly 40 engages counterbalance system 30, and a disconnect position, where motor assembly 40 has been disengaged by the operation of handle 516. The handle 516 includes a spool portion 521 for taking up cable C during actuation of handle 516 toward the disconnect position and a grip portion 522 extending radially outwardly from spool portion 521, as shown, providing a portion of handle 516 that is more easily grasped by a user and which may supply additional leverage to operate handle 516. Grip portion 522 may be of any suitable length, shape, or size to provide such leverage and graspable surfaces and may be formed integrally with spool portion 521. In the embodiment shown, grip portion 522 is a generally channel-like member extending generally radially outward from spool portion 521 at a first end 523 and terminating at a second end 524. At least one projection 525, 525 may extend inwardly toward the jamb 14 spacing grip portion 522 therefrom. As best shown in FIGS. 13 and 15, a pair of projections 525, 525 extend from the walls 526, 526 of the channel-like grip portion 522 at second end 524 to facilitate grasping of handle 516. Several of the surfaces of grip portion 522 are rounded to provide greater comfort to the user including the edge 528 of projections 525, 525, the grip portion's shoulders 529, 529, and the butt 530 of grip portion 522. Also, the edge 528 of projections 525, 525 may be made generally semicircular to allow the user to operate handle 516 by this portion of the grip 522, if so desired. Also, when the grip portion 522 is raised extending inwardly into the garage to a greater extent, the rounded and semicircular edge 528 is less likely to catch or snag on articles within the garage (FIG. 14). Spool portion 521 may include a generally cylindrical wall 535, which is provided with a slot 536 or other suitable opening for receipt of cable C. A circular web 537 substantially spans interior of the cylindrical wall 535 and has a bored collar 539 extending axially outward from web 537 and receiving bolt 520 therethrough. A cable guide 538, which, as shown, may be a generally L-shaped member extends axially inwardly from web 537 beneath cable C to guide the cable C when any loss of tension occurs, such as, during rotation of the handle 516 from the disconnect position (FIG. 14) to the operational position (FIG. 13). Web 537 may further be provided with a cable-securing assembly, generally indicated by the numeral 540, which conventionally may be a post, loop, hook, or other member to which the cable is secured. As shown in FIG. 13, the cable-securing assembly 540 has a cable stop 541 fixedly attached proximate an end of cable C and, then, seated within a retainer 542 to restrict axial movement of the cable C relative to the cable stop 541. From retainer 542 Cable C is routed over cable guide 538 and through slot 536 to exit the interior of spool portion 521 (FIG. 15). The cable C is then routed to the disconnect actuator 80 as described in the previous embodiment. As best shown in FIG. 15, when the handle 516 is in the operational position, the cable C exits slot 536 substantially tangentially to the exterior surface of cylindrical wall 535. To further tension cable C causing disengagement of the motor assembly 40 from counterbalance system 30, the handle 516 is rotated about bolt 520 such that it attains a disconnect position 516′ shown in FIG. 14. As the handle 516 is urged toward the disconnect position, a length of cable C is drawn around the spool portion 521, which correspondingly urges actuator 80 toward the disconnect position, as previously described. Once handle 516 has been rotated to the disconnect position 516′ (FIG. 14), handle 516 may be locked in this position as by a detent 550 or other suitable locking member. As best seen in FIG. 13, detent 550 may be located proximate first end 523 of grip portion 522 and the spool portion 521, such that the detent 550 engages an edge 551 of bracket 517 when grip portion 522 nears contact with bracket 517. To effect locking of handle 516, detent 550 flexes beneath edge 551 of bracket 517 as the detent 550 is urged past edge 551. Once beyond edge 551, detent 550 rebounds or “snaps” to its unflexed position behind edge 551 creating a positive stop against rotation of handle 516′ toward the operative position. The interaction of detent 550 with edge 551 of bracket 517 also serves to indicate release of the door D with an audible click or by vibration through handle 516. To disconnect motor assembly 40, grip portion 522 may be grasped and urged upward causing rotation of spool portion 521 about bolt 520 drawing the cable C around at least a portion of the circumference of spool portion 521 increasing the tension on cable C to cause movement of actuator 80 as previously described. Eventually, handle assembly 515 fully disconnects motor 40 from counterbalance system 30 with handle 516 attaining a disconnect position 516′ shown in FIG. 14. The handle 516 may be further rotated to cause detent 550 to engage the edge 551 of bracket 517 locking the handle 516 in the disconnect position 516′. Thus, in the disconnect position of handle 516, the operator motor assembly 40 is in the operating position and the drive assembly 55 has disconnected the motor 41 and the drive tube 31 such that the door D can be freely manually raised or lowered as assisted by the counterbalance system 30. It is to be appreciated that operator motor assembly 40 may assist in seating the door D in the fully closed position, if necessary. In some, particularly low headroom, arrangements of doors, tracks and rollers, there may be instances where the top panel is not fully seated when the door is ostensibly in the closed position. In such cases, the rotation of operator motor assembly 40 may be employed to fully seat the top panel P of door D in the closed position preparatory to assuming the locked position. When the door D and operator motor assembly 40 are actuated to effect opening of the door D, the operator motor assembly 40 rotates from the locked position to the operating position prior to movement of the door D. As the operator motor assembly 40 approaches the operating position, the spring loaded plunger 132 engages cylindrical stop 140 and depresses spring 133 until the force of plunger 132 and the rotation of the operator motor assembly move operator motor assembly 40 into the operating position secured by motor retaining assembly 130. Thereafter continued actuation of motor 41 proceeds in normal opening of the door D with the operator motor assembly 40 remaining in the operating position during the opening and closing sequence until the door D again reaches the closed position as described hereinabove. During the normal operating cycle the disconnect actuator 80 is positioned as shown in FIG. 2 with the disconnect sleeve 70 engaging the worm wheel 54. Should an obstruction be encountered during lowering of the door D, the handle 116,516 may be moved from position 116,516 to the second position 116′,516′ to move disconnect plate 90, disconnect actuator 80 and thus the disconnect sleeve 70 from the engaged position with worm wheel 54 to the disengaged position. Thus disengaged from operator motor assembly 40, the door D may be freely raised or lowered manually until such time as the handle 116,516 is released from the second position 116′,516′ and allowed to resume the first, position, thereby engaging the disconnect sleeve 70 with worm wheel 54. The operator motor assembly 40 may be provided with a mercury switch S (FIG. 2) or other indicator to signal rotation of the motor 41 from the operating position as a secondary indicia of contact with an obstruction when the door D is not in the closed position. It is to be appreciated that the handle assembly 115, 515 may be actuated from the first position to the second disengaged position when the door D is in the closed position. In such instance, it is to be noted that the cable C will manually effect both a pivoting of the operator motor assembly 40 from the locked position to the operating position and disengagement of disconnect sleeve 70 from worm wheel 54 such that the door can be manually raised and manipulated as necessary, as in the event of a power loss. Further, it will be appreciated that handle assembly 115, 515 may be arbitrarily located at any position desired within the structure by accordingly routing Cable C. Door operating system 10 may include a remote light assembly, generally indicated by the numeral 600 in FIGS. 1, 16 and 17, that is in communication with the operator motor such that operation of the motor activates the remote light assembly. Remote light assembly 600 is in electrical communication with a power supply, represented by an outlet 601 powering a light source 602 such as a lightbulb 603. Conventionally, lightbulb 603 may be received in a socket 604 located within a base assembly, generally indicated by the numeral 605, and connected to outlet 601 as by a plug 607. Plug 607 may be located at any point on the base and preferably extends axially outwardly therefrom opposite socket 604. To allow rotation of the base assembly 605 relative to the plane defined by the surface of outlet 601, plug 607 is journaled to base 605. As best shown in FIGS. 16 and 17, a receiver assembly, generally indicated by the numeral 610, is located on base assembly 605 and may be gimbaled thereto to permit positioning of the receiver assembly 610 for reception of a signal S when light assembly 600 is mounted in various positions within the garage. The receiver assembly 610 generally includes a base portion 611 that has a pair of arms 612, 612 extending outwardly therefrom and a sensing element 613 supported on arms 612, 612. Inwardly facing L-shaped jaws 614, 614 formed on the ends of arms 612, 612 grasp sensing element 613 selectively securing element 613 to receiver assembly 610. As best shown in FIG. 16, sensing element 613 is received between arms 612, 612 and electrically connected to the base assembly 605 as by prongs 615 that penetrate base portion 611 at slots 616. In this way, a defective or worn sensing element 613 may be easily replaced by removing sensing element 613 from the grasp of jaws 614 and pulling prongs 615 from slot 616. As best shown in FIG. 17, when in a stowed position within base assembly 605 shown in solid lines in FIG. 17, sensing element 613 has been rotated and pivoted such that sensing element 613 is substantially parallel to the side walls 617, 617 of base assembly 605 and is received in the recess 618 defined between walls 617, 617. In the stowed position (FIG. 17) prongs 615 are not in electrical communication with the base portion 605. To ready the receiver assembly 610 for operation, receiver assembly is pivoted to an extended position 610′, shown in chain lines and described more completely below. When in the extended position 610′, prongs 615 make electrical contact within base assembly allowing sensing element 613 to control illumination of lightbulb 603. An annular gimbal member, generally indicated by the numeral 620, pivotally attaches to base assembly 605 as by ears 621, 621 extending from base assembly 605 receiving opposed spindles 622, 622 extending radially outward from gimbal 620. Gimbal 620 receives base portion 611, as by an interference fits such that base portion 611 may rotate within annular gimbal 620. Receiver assembly 610 may be urged from a first or stowed position, within base assembly 605 toward a second or receiving position 610′ shown in broken lines, where the sensing element 613 extends outwardly of a side 624 of base assembly 605 by pivoting base portion 611 with gimbal 620 about spindles 622. As indicated by arrows, gimbal 620 allows sensing element 613 to be rotated in the plane defined by base portion 611 and/or pivoted about spindles 622 to optimally receive a signal S from operator 10 (FIG. 1). Operator 10 includes a transmitter, generally indicated by the numeral 625, located within or on operator 10 to transmit a signal S, as by a radio frequency or infrared emitter, to receiver assembly 610. As shown in FIG. 1, transmitter 625 may be located rearwardly of operator 10 such that signal S is directed inwardly within the garage. Transmitter 625 may also be placed within the cover of operator 10 and transmit signal S through the operator cover or an opening formed therein. Transmitter 625 is in operative communication with operator 10 such that transmitter 625 is activated during the operating cycle of motor 41 directing signal S toward receiver assembly 610. Upon receipt of the signal S, sensing element 613 assumes an on condition effecting illumination of lightbulb 603. If desired, either transmitter 625 or receiver assembly 610 may be preset to illuminate lightbulb 603 for a period of time after the system 10 has stopped operation of the motor 41. Thus, it should be evident that the overhead door locking operator disclosed herein carries out one or more of the objects of the present invention set forth above and otherwise constitutes an advantageous contribution to the art. As will be apparent to persons skilled in the art, modifications can be made to the preferred embodiments disclosed herein without departing from the spirit of the invention, the scope of the invention herein being limited solely by the scope of the attached claims. | <SOH> BACKGROUND ART <EOH>Motorized apparatus for opening and closing sectional overhead doors have long been known in the art. These powered door operators were developed in part due to extremely large, heavy commercial doors for industrial buildings, warehouses, and the like where opening and closing of the doors essentially mandates power assistance. Later, homeowners' demands for the convenience and safety of door operators resulted in an extremely large market for powered door operators for residential usage. The vast majority of motorized operators for residential garage doors employ a trolley-type system that applies force to a section of the door for powering it between the open and closed positions. Another type of motorized operator is known as a “jack-shaft” operator, which is used virtually exclusively in commercial applications and is so named by virtue of similarities with transmission devices where the power or drive shaft is parallel to the driven shaft, with the transfer of power occurring mechanically, as by gears, belts, or chains between the drive shaft and a driven shaft, normally part of the door counterbalance system, controlling door position. While some efforts have been made to configure hydraulically or pneumatically-driven operators, such efforts have not achieved any substantial extent of commercial acceptance. The well-known trolley-type door operators are attached to the ceiling and connected directly to the top section of a garage door and for universal application may be powered to operate doors of vastly different size and weight, even with little or no assistance from a counterbalance system for the door. Since the operating force capability of trolley-type operators is normally very high, force adjustments are normally necessary and provided to allow for varying conditions and to allow the operator to be adjusted for reversing force sensitivity, depending on the application. When a garage door and trolley-type operator are initially installed and both adjusted for optimum performance, the overhead door system can perform well as designed. However, as the system ages, additional friction develops in door and operator components due to loss of lubrication at rollers and hinges. Also, the door can absorb moisture and become heavier, and counterbalance springs can lose some of their original torsional force. These and similar factors can significantly alter the operating characteristics seen by the operator, which may produce erratic door operation such as stops and reversals of the door at unprogrammed locations in the operating cycle. Rather than ascertaining and correcting the conditions affecting door performance, which is likely beyond a homeowner's capability, or engaging a qualified service person, homeowners frequently increase the force adjustment to the maximum setting. However, setting an operator on a maximum force adjustment creates an unsafe condition in that the operator becomes highly insensitive to obstructions. In the event a maximum force setting is effected on a trolley-type operator, the unsafe condition may also be dramatically exemplified in the event of a broken spring or springs. In such case, if the operator is disconnected from the door in the fully open position during an emergency or if faulty door operation is being investigated, one half or all of the uncounterbalanced weight of the door may propel the door to the closed position with a guillotine-like effect. Another problem with trolley-type door operators is that they do not have a mechanism for automatically disengaging the drive system from the door if the door encounters an obstruction. This necessitates the considerable effort and cost which has been put into developing a variety of ways, such as sensors and encoders, to signal the operator controls when an obstruction is encountered. In virtually all instances, manual disconnect mechanisms between the door and operator are required to make it possible to operate the door manually in the case of power failures or fire and emergency situations where entrapment occurs and the door needs to be disconnected from the operator to free an obstruction. These mechanical disconnects, when coupled with a maximum force setting adjustment of the operator, can readily exert a force on a person or object which may be sufficiently high to bind the disconnect mechanism and render it difficult, if not impossible, to actuate. In addition to the serious operational deficiencies noted above, manual disconnects, which are normally a rope with a handle, must extend within six feet of the floor to permit grasping and actuation by a person. In the case of a garage opening for a single car, the centrally-located manual disconnect rope and handle, in being positioned medially, can catch on a vehicle during door movement or be difficult to reach due to its positioning over a vehicle located in the garage. Trolley-type door operators raise a host of peripheral problems due to the necessity for mounting the operator to the ceiling or other structure substantially medially of and to the rear of the sectional door in the fully open position. Operationally, trolley-type operators are susceptible to other difficulties due to their basic mode of interrelation with a sectional door. Problems are frequently encountered by way of misalignment and damage because the connecting arm of the operator is attached directly to the door for force transmission, totally independent of the counterbalance system. Another source of problems is the necessity for a precise, secure mounting of the motor and trolley rails which may not be optimally available in many garage structures. Thus, trolley-type operators, although widely used, do possess certain disadvantageous and, in certain instances, even dangerous characteristics. The usage of jack-shaft operators has been limited virtually exclusively to commercial building applications where a large portion of the door stays in the vertical position. This occurs where a door opening may be 15, 20, or more feet in height, with only a portion of the opening being required for the ingress and egress of vehicles. These jack-shaft operators are not attached to the door but attach to a component of the counterbalance system, such as the shaft or a cable drum. Due to this type of connection to the counterbalance system, these operators require that a substantial door weight be maintained on the suspension system, as is the case where a main portion of the door is always in a vertical position. This is necessary because jack-shaft operators characteristically only drive or lift the door from the closed to the open position and rely on the weight of the door to move the door from the open to the closed position, with the suspension cables attached to the counterbalance system controlling only the closing rate. Such a one-way drive in a jack-shaft operator produces potential problems if the door binds or encounters an obstruction upon downward movement. In such case, the operator may continue to unload the suspension cables, such that if the door is subsequently freed or the obstruction is removed, the door is able to free-fall, with the potential of damage to the door or anything in its path. Such unloading of the suspension cables can also result in the cables coming off the cable storage drums, thus requiring substantial servicing before normal operation can be resumed. Jack-shaft operators are normally mounted outside the tracks and may be firmly attached to a doorjamb rather than suspended from the ceiling or wall above the header. While there is normally ample jamb space to the sides of a door or above the header in a commercial installation, these areas frequently have only limited space in residential garage applications. Further, the fact that normal jack-shaft operators require much of the door to be maintained in a vertical position absolutely mitigates against their use in residential applications where the door must be capable of assuming essentially a horizontal position since, in many instances, substantially the entire height of the door opening is required for vehicle clearance during ingress and egress. In order to permit manual operation of a sectional door in certain circumstances, such as the loss of electrical power, provision must be made for disconnecting the operator from the drive shaft. In most instances this disconnect function is effected by physically moving the drive gear of the motor out of engagement with a driven gear associated with the drive shaft. Providing for such gear separation normally results in a complex, oversized gear design which is not compatible with providing a compact operator which can feasibly be located between the drive shaft for the counterbalance system and the door. Larger units to accommodate gear design have conventionally required installation at or near the end of the drive shaft which may result in shaft deflection that can cause one of the two cables interconnecting the counterbalance drums and the door to carry a disproportionate share of the weight of the door. Another common problem associated particularly with jack-shaft operators is the tendency to generate excessive objectionable noise. In general, the more components, and the larger the components, employed in power transmission the greater the noise level. Common operator designs employing chain drives and high speed motors with spur gear reducers are notorious for creating high noise levels. While some prior art operators have employed vibration dampers and other noise reduction devices, most are only partially successful and add undesirable cost to the operator. Another requirement in jack-shaft operators is mechanism to effect locking of the door when it is in the closed position. Various types of levers, bars and the like have been provided in the prior art which are mounted on the door or on the adjacent track or jamb and interact to lock the door in the closed position. In addition to the locking mechanism which is separate from the operator there is normally an actuator which senses slack in the lift cables which is caused by a raising of the door without the operator running, as in an unauthorized entry, and activates the locking mechanism. Besides adding operational complexity, such locking mechanisms are unreliable and, also, introduce an additional undesirable cost to the operator system. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>FIG. 1 is a rear perspective view of a sectional overhead garage door installation showing a motorized operator and remote light assembly according to the concepts of the present invention installed in operative relation thereto, with the operator depicted in its operating position in solid lines and the door locking position in chain lines and further schematically depicting transmission of a signal from the operator to the remote light assembly. FIG. 2 is an enlarged perspective view of the motorized operator of FIG. 1 with the cover removed and portions broken away to show the mechanical interconnection of the motorized operator with the drive tube of the counterbalancing system. FIG. 3 is a further enlarged exploded perspective view showing details of the drive system and the disconnect assembly. FIG. 4 is a further enlarged perspective view of the motorized operator of FIG. 1 with portions of the cover broken away to show additional details of the drive elements and the disconnect assembly. FIG. 5 is an exploded perspective view showing details of operative components of the retaining assembly which selectively secures the operator in the door operating position. FIG. 6 is an enlarged fragmentary portion of the sectional overhead door installation of FIG. 1 showing details of the placement and structure of the manual disconnect assembly. FIG. 7 is an enlarged exploded perspective view showing details of an alternate embodiment of drive tube drive assembly according to the concepts of the present invention. FIG. 8 is a perspective view of the motorized operator of the alternate embodiment of FIG. 7 with the gear removed to show the mechanical interconnection of the motorized operator with the drive tube of the counterbalancing system in the assembled configuration. FIG. 9 is a perspective view of a motorized operator system having a modified form of locking assembly. FIG. 10 is an exploded perspective view showing details of the locking assembly of FIG. 9 including a biasing member and an alternate form of biasing member. FIG. 11 is a sectional view of the modified form of locking assembly taken substantially along the line 11 - 11 of FIG. 9 showing details of the biasing member having moved the disconnect rod to engage the motor assembly. FIG. 12 is a sectional view similar to FIG. 11 showing the locking rod out of engagement with the motor assembly preparatory to pivoting the motor to lock the door. FIG. 13 is an enlarged fragmentary portion of the sectional overhead door installation of FIG. 1 shown from behind the door outwardly and showing details of the structure of an alternative handle assembly in a manual disconnect assembly. FIG. 14 is an enlarged fragmentary portion similar to FIG. 13 with the handle assembly moved to disconnect the motor assembly from the counterbalance system. FIG. 15 is an enlarged fragmentary portion similar to FIG. 13 viewed from outside the door inwardly to show additional details of the handle assembly. FIG. 16 is an enlarged fragmentary portion of the remote light assembly shown in FIG. 1 having a receiver assembly depicted in a receiving position. FIG. 17 is an enlarged fragmentary portion similar to FIG. 16 with the receiver assembly depicted in a stowed position in solid lines and a signal receiving position in chain lines. detailed-description description="Detailed Description" end="lead"? | 20050124 | 20061205 | 20050616 | 79124.0 | 1 | PUROL, DAVID M | OVERHEAD DOOR LOCKING OPERATOR WITH REMOTE LIGHT ASSEMBLY | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,041,919 | ACCEPTED | NAVIGATING UAVS IN FORMATION | Navigating UAVs in formation, including assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, where the navigation algorithm includes repeatedly comparing the UAV's intended position and the UAV's actual position and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. The actual position of the UAV may be taken from a GPS receiver on board the UAV. | 1. A method for navigating UAVs in formation, the method comprising: assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, the navigation algorithm including: repeatedly comparing the UAV's intended position and the UAV's actual position, the actual position taken from a GPS receiver; and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. 2. The method of claim 1 wherein: assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern further comprises designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position; and identifying a waypoint for each UAV in dependence upon its pattern position further comprises designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. 3. The method of claim 1 wherein each UAV's intended position is specified by the UAV's position in the pattern, a cross track to the UAV's waypoint, and a flight schedule. 4. The method of claim 1 wherein piloting the UAVs in dependence upon a navigation algorithm further comprises: identifying a cross track to a waypoint for each UAV, the cross track having a cross track direction; piloting the UAV to a starting point on the cross track; calculating an airspeed for flying from the starting point to the waypoint on schedule; calculating a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction; and flying the UAV on the heading at the airspeed. 5. The method of claim 1 wherein calculating a corrective flight vector further comprises: selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint; calculating a corrective airspeed for arriving at the corrective waypoint on schedule; and calculating a corrective heading in dependence upon the calculated airspeed. 6. The method of claim 5 wherein selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint further comprises selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. 7. The method of claim 5 wherein calculating a corrective airspeed for arriving at the corrective waypoint on schedule further comprises calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule, including dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. 8. A system for navigating UAVs in formation, the system comprising: means for assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; means for identifying a waypoint for each UAV in dependence upon the UAV's pattern position; means for piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm; means for repeatedly comparing the UAV's intended position and the UAV's actual position, the actual position taken from a GPS receiver; and means for calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. 9. The system of claim 8 wherein: means for assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern further comprises means for designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position; and means for identifying a waypoint for each UAV in dependence upon its pattern position further comprises means for designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. 10. The system of claim 8 wherein means for piloting the UAVs in dependence upon a navigation algorithm further comprises: means for identifying a cross track to a waypoint for each UAV, the cross track having a cross track direction; means for piloting the UAV to a starting point on the cross track; means for calculating an airspeed for flying from the starting point to the waypoint on schedule; means for calculating a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction; and means for flying the UAV on the heading at the airspeed. 11. The system of claim 8 wherein means for calculating a corrective flight vector further comprises: means for selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint; means for calculating a corrective airspeed for arriving at the corrective waypoint on schedule; and means for calculating a corrective heading in dependence upon the calculated airspeed. 12. The system of claim 11 wherein means for selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint further comprises means for selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. 13. The system of claim 11 wherein means for calculating a corrective airspeed for arriving at the corrective waypoint on schedule further comprises means for calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule, including means for dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. 14. A computer program product for navigating UAVs in formation, the computer program product comprising: a computer readable recording medium; means, recorded on the recording medium, for assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; means, recorded on the recording medium, for identifying a waypoint for each UAV in dependence upon the UAV's pattern position; means, recorded on the recording medium, for piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm; means, recorded on the recording medium, for repeatedly comparing the UAV's intended position and the UAV's actual position, the actual position taken from a GPS receiver; and means, recorded on the recording medium, for calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. 15. The computer program product of claim 14 wherein: means, recorded on the recording medium, for assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern further comprises means, recorded on the recording medium, for designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position; and means, recorded on the recording medium, for identifying a waypoint for each UAV in dependence upon its pattern position further comprises means, recorded on the recording medium, for designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. 16. The computer program product of claim 14 wherein each UAV's intended position is specified by the UAV's position in the pattern, a cross track to the UAV's waypoint, and a flight schedule. 17. The computer program product of claim 14 wherein means, recorded on the recording medium, for piloting the UAVs in dependence upon a navigation algorithm further comprises: means, recorded on the recording medium, for identifying a cross track to a waypoint for each UAV, the cross track having a cross track direction; means, recorded on the recording medium, for piloting the UAV to a starting point on the cross track; means, recorded on the recording medium, for calculating an airspeed for flying from the starting point to the waypoint on schedule; means, recorded on the recording medium, for calculating a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction; and means, recorded on the recording medium, for flying the UAV on the heading at the airspeed. 18. The computer program product of claim 14 wherein means, recorded on the recording medium, for calculating a corrective flight vector further comprises: means, recorded on the recording medium, for selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint; means, recorded on the recording medium, for calculating a corrective airspeed for arriving at the corrective waypoint on schedule; and means, recorded on the recording medium, for calculating a corrective heading in dependence upon the calculated airspeed. 19. The computer program product of claim 18 wherein means, recorded on the recording medium, for selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint further comprises means, recorded on the recording medium, for selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. 20. The computer program product of claim 18 wherein means, recorded on the recording medium, for calculating a corrective airspeed for arriving at the corrective waypoint on schedule further comprises means, recorded on the recording medium, for calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule, including means, recorded on the recording medium, for dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. | BACKGROUND OF THE INVENTION 1. Field of the Invention The field of the invention is data processing, or, more specifically, methods, systems, and products for navigating UAVs in formation. 2. Description of Related Art Many form is of UAV are available in prior art, both domestically and internationally. Their payload weight carrying capability, their accommodations (volume, environment), their mission profiles (altitude, range, duration), and their command, control and data acquisition capabilities vary significantly. Routine civil access to these various UAV assets is in an embryonic state. Conventional UAVs are typically manually controlled by an operator who may view aspects of a UAV's flight using cameras installed on the UAV with images provided through downlink telemetry. Navigating such UAVs from a starting position to one or more waypoints requires an operator to have specific knowledge of the UAV's flight, including such aspects as starting location, the UAV's current location, waypoint locations, and so on. Operators of prior art UAVs usually are required generally to manually control the UAV from a starting position to a waypoint with little aid from automation. There is therefore an ongoing need for improvement in the area of UAV navigations. SUMMARY OF THE INVENTION Exemplary methods, systems, and products are described for efficient, automated navigation of UAVs, including navigating UAVs in formation. That is, exemplary methods, systems, and products are described for navigating UAVs in formation, including assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, where the navigation algorithm includes repeatedly comparing the UAV's intended position and the UAV's actual position and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. The actual position of the UAV may be taken from a GPS receiver on board the UAV. Assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern may include designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position, and identifying a waypoint for each UAV in dependence upon its pattern position may be carried out by designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. Each UAV's intended position may be specified by the UAV's position in the pattern, a cross track to the UAV's waypoint, and a flight schedule. Piloting the UAVs in dependence upon a navigation algorithm may include identifying a cross track to a waypoint for each UAV, the cross track having a cross track direction; piloting the UAV to a starting point on the cross track; calculating an airspeed for flying from the starting point to the waypoint on schedule; calculating a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction; and flying the UAV on the heading at the airspeed. Calculating a corrective flight vector may be carried out by selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint; calculating a corrective airspeed for arriving at the corrective waypoint on schedule; and calculating a corrective heading in dependence upon the calculated airspeed. Selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint may include selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. Calculating t corrective airspeed for arriving at the corrective waypoint on schedule may be carried out by calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule, including dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular descriptions of exemplary embodiments of the invention as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts of exemplary embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 sets forth a system diagram illustrating relations among components of an exemplary system for navigating a UAV. FIG. 2 is a block diagram of an exemplary UAV showing relations among components that includes automated computing machinery. FIG. 3 is a block diagram of an exemplary remote control device showing relations among components that includes automated computing machinery. FIG. 4 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving in a remote control device a user's selection of a GUI map pixel that represents a waypoint for UAV navigation. FIG. 4A is a data flow diagram illustrating an exemplary method for receiving downlink telemetry. FIG. 4B sets forth a data flow diagram illustrating an exemplary method for transmitting uplink telemetry. FIG. 5 sets forth a block diagram that includes a GUI displaying a map and a corresponding area of the surface of the Earth. FIG. 6 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm. FIG. 7 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 6. FIG. 8 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm. FIG. 9 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 8. FIG. 10 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm. FIG. 11 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 10. FIG. 12 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving in a remote control device a user's selection of a GUI map pixel that represents a waypoint for UAV navigation. FIG. 13 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 14 sets forth a line drawing illustrating a method of calculating a heading with a cross wind to achieve a particular ground course. FIG. 15 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 13. FIG. 16 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 17 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 16. FIG. 18 sets forth a flow chart illustrating an exemplary method for navigating UAVs in formation. FIGS. 19A and 19B are line drawings illustrating exemplary relations among UAVs flying in formation. FIG. 20 sets forth a flow chart illustrating an exemplary method of piloting the UAVs in dependence upon a navigation algorithm. FIG. 21 sets forth a line drawing illustrating an exemplary method of calculating airspeed and heading according to the method of FIG. 21. FIG. 22 sets forth a flow chart illustrating an exemplary method of calculating a corrective flight vector. FIG. 23 is a line drawing illustrating application of the method of FIG. 22, showing relations among an intended position, an error threshold, an actual position, a corrective flight vector, and a cross track to a waypoint. FIG. 24 sets forth a line drawing illustrating an exemplary method of calculating corrective airspeed and corrective heading according to the method of FIG. 22. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS Introduction The present invention is described to a large extent in this specification in terms of methods for navigating UAVs in formation. Persons skilled in the art, however, will recognize that any computer system that includes suitable programming means for operating in accordance with the disclosed methods also falls well within the scope of the present invention. Suitable programming means include any means for directing a computer system to execute the steps of the method of the invention, including for example, systems included of processing units and arithmetic-logic circuits coupled to computer memory, which systems have the capability of storing in computer memory, which computer memory includes electronic circuits configured to store data and program instructions, programmed steps of the method of the invention for execution by a processing unit. The invention also may be embodied in a computer program product, such as a diskette or other recording medium, for use with any suitable data processing system. Embodiments of a computer program product may be implemented by use of any recording medium for machine-readable information, including magnetic media, optical media, or other suitable media. Persons skilled in the art will immediately recognize that any computer system having suitable programming means will be capable of executing the steps of the method of the invention as embodied in a program product. Persons skilled in the art will recognize immediately that, although most of the exemplary embodiments described in this specification are oriented to software installed and executing on computer hardware, nevertheless, alternative embodiments implemented as firmware or as hardware are well within the scope of the present invention. DEFINITIONS “Airspeed” means UAV airspeed, the speed of the UAV through the air. A “cross track” is a fixed course from a starting point directly to a waypoint. A cross track has a direction, a ‘cross track direction,’ that is the direction straight from a starting point to a waypoint. That is, a cross track direction is the heading that a UAV would fly directly from a starting point to a waypoint in the absence of wind. “GUI” means graphical user interface, a display means for a computer screen. “Heading” means the compass heading of the UAV. “Course” means the direction of travel of the UAV over the ground. In the absence of wind, or in the presence of a straight tailwind or straight headwind, the course and the heading are the same direction. In the presence of crosswind, the course and the heading are different directions. “Position” refers to a location in the air or over the ground. ‘Position’ is typically specified as Earth coordinates, latitude and longitude. A specification of position may also include altitude. A “waypoint” is a position chosen as a destination for navigation of a route. A route has one or more waypoints. That is, a route is composed of waypoints, including at least one final waypoint, and one or more intermediate waypoints. “TDMA” stands for Time Division Multiple Access, a technology for delivering digital wireless service using time-division multiplexing. TDMA works by dividing a radio frequency into time slots and then allocating slots to multiple calls. In this way, a single frequency can support multiple, simultaneous data channels. TDMA is used by GSM. “GSM” stands for Global System for Mobile Communications, a digital cellular standard. GSM at this time is the de facto standard for wireless digital communications in Europe and Asia. “CDPD” stands for Cellular Digital Packet Data, a data transmission technology developed for use on cellular phone frequencies. CDPD uses unused cellular channels to transmit data in packets. CDPD supports data transfer rates of up to 19.2 Kbps. “GPRS” stands for General Packet Radio Service, a standard for wireless data communications which runs at speeds up to 150 Kbps, compared with current GSM systems which cannot support more than about 9.6 Kbps. GPRS, which supports a wide range of speeds, is an efficient use of limited bandwidth and is particularly suited for sending and receiving small bursts of data, such as e-mail and Web browsing, as well as large volumes of data. “EDGE” stands for Enhanced Data Rates for GSM Evolution, a standard for wireless data communications supporting data transfer rates of more than 300 Kbps. GPRS and EDGE are considered interim steps on the road to UMTS. “UMTS” stands for Universal Mobile Telecommunication System, a standard for wireless data communications supporting data transfer rates of up to 2 Mpbs. UMTS is also referred to W-CDMA for Wideband Code Division Multiple Access. Navigating a UAV with Telemetry Through a Socket Methods, systems, and products for navigating a UAV are explained with reference to the accompanying drawings, beginning with FIG. 1. FIG. 1 sets forth a system diagram illustrating relations among components of an exemplary system for navigating a UAV. The system of FIG. 1 includes UAV (100) and UAV (126), flying in formation, each of which includes a GPS (Global Positioning System) receiver (not shown) that receives a steady stream of GPS data from satellites (190, 192). For convenience of explanation, only two GPS satellites are shown in FIG. 1, although the GPS satellite network in fact includes 24 GPS satellites. For convenience of explanation in the example of FIG. 1, only two UAVs are shown, but in fact any number of UAVs may be navigated together in formation according to embodiments of the present invention. The system of FIG. 1 operates to navigate a UAV by receiving in a remote control device a user's selection of a GUI map pixel that represents a waypoint for UAV navigation. Each such pixel has a location on a GUI map, typically specified as a row and column position. Examples of remote control devices in FIG. 1 include mobile telephone (110), workstation (104), laptop computer (106), and PDA (Personal Digital Assistant) (120). Each such remote control device is capable of supporting a GUI display of a map of the surface of the Earth in which each pixel on the GUI map represents a position on the Earth. Each remote control device also supports at least one user input device through which a user may enter the user's selection of a pixel. Examples of user input devices in the system of FIG. 1 include telephone keypad (122), workstation keyboard (114), workstation joystick (112), laptop keyboard (116) and PDA touch screen (118). The system of FIG. 1 typically is capable of operating a remote control device to map the pixel's location on the GUI to Earth coordinates of a waypoint. The remote control device is often capable of receiving downlink telemetry including starting position from a GPS receiver on the UAV through the socket. In fact, the remote control device is often receiving downlink telemetry that includes a steady stream of GPS positions of the UAV. Receiving a starting position therefore is typically carried out by taking the current position of the UAV when the user selects the pixel as the starting position. In the example of FIG. 1, the remote control device generally receives the starting position from the UAV through wireless network (102). The remote control device is often capable of transmitting uplink telemetry including the coordinates of the waypoint, flight control instructions, or UAV instructions through a socket on the remote control devices. Wireless network (102) is implemented using any wireless data transmission technology as will occur to those of skill in the art including, for example, TDMA, GSM, CDPD, GPRS, EDGE, and UMTS. In a one embodiment, a data communications link layer is implemented using one of these technologies, a data communications network layer is implemented with the Internet Protocol (“IP”), and a data communications transmission layer is implemented using the Transmission Control Protocol (“TCP”). In such systems, telemetry between the UAV and remote control devices, including starting positions, UAV instructions, and flight control instructions, are transmitted using an application-level protocol such as, for example, the HyperText Transmission Protocol (“HTTP”), the Wireless Application Protocol (“WAP”), the Handheld Device Transmission Protocol (“HDTP”), or any other data communications protocol as will occur to those of skill in the art. The system of FIG. 1 typically is capable of calculating a heading in dependence upon the starting position, the coordinates of the waypoint, and a navigation algorithm, identifying flight control instructions for flying the UAV on the heading, and transmitting the flight control instructions from the remote control device to the UAV. UAVs according to embodiments of the present invention typically include, not only an aircraft, but also automated computing machinery capable of receiving GPS data, operating telemetry between the UAV and one or more remote control devices, and navigating a UAV among waypoints. FIG. 2 is a block diagram of an exemplary UAV showing relations among components that includes automated computing machinery. In FIG. 2, UAV (100) includes a processor (164), also typically referred to as a central processing unit or ‘CPU.’ The processor may be a microprocessor, a programmable control unit, or any other form of processor useful according to the form factor of a particular UAV as will occur to those of skill in the art. Other components of UAV (100) are coupled for data transfer to processor (164) through system bus (160). UAV (100) includes random access memory or ‘RAM’ (166). Stored in RAM (166) is an application program (152) that implements inventive methods according to embodiments of the present invention. Among other things, application program (158) includes computer program instructions capable of navigating UAVs in formation according to embodiments of the present invention, including computer program steps that execute generally by assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, where the navigation algorithm includes repeatedly comparing the UAV's intended position and the UAV's actual position, the actual position taken from a GPS receiver, and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. This capability of navigating UAVs in formation is described in more detail below in this specification. In some embodiments, the application programming runs on an OSGi service framework (156). OSGi Stands for ‘Open Services Gateway Initiative.’ The OSGi specification is a Java-based application layer framework that provides vendor neutral application layer APIs and functions. An OSGi service framework (156) is written in Java and therefore typically runs on a Java Virtual Machine (JVM) (154) which in turn runs on an operating system (150). Examples of operating systems useful in UAVs according to the present invention include Unix, AIX™, and Microsoft Windows™. In OSGi, the framework is a hosting platform for running ‘services’. Services are the main building blocks for creating applications according to the OSGi. A service is a group of Java classes and interfaces that implement a certain feature. The OSGi specification provides a number of standard services. For example, OSGi provides a standard HTTP service that can respond to requests from HTTP clients, such as, for example, remote control devices according to embodiments of the present invention. That is, such remote control devices are enabled to communicate with a UAV having an HTTP service by use of data communications messages in the HTTP protocol. Services in OSGi are packaged in ‘bundles’ with other files, images, and resources that the services need for execution. A bundle is a Java archive or ‘JAR’ file including one or more service implementations, an activator class, and a manifest file. An activator class is a Java class that the service framework uses to start and stop a bundle. A manifest file is a standard text file that describes the contents of the bundle. The service framework in OSGi also includes a service registry. The service registry includes a service registration including the service's name and an instance of a class that implements the service for each bundle installed on the framework and registered with the service registry. A bundle may request services that are not included in the bundle, but are registered on the framework service registry. To find a service, a bundle performs a query on the framework's service registry. In the UAV (100) of FIG. 2, software programs and other useful information may be stored in RAM or in non-volatile memory (168). Non-volatile memory (168) may be implemented as a magnetic disk drive such as a micro-drive, an optical disk drive, static read only memory (‘ROM’), electrically erasable programmable read-only memory space (‘EEPROM’ or ‘flash’ memory), or otherwise as will occur to those of skill in the art. UAV (100) includes communications adapter (170) implementing data communications connections (184) to other computers (162), which may be wireless networks, satellites, remote control devices, servers, or others as will occur to those of skill in the art. Communications adapter (170) advantageously facilitates receiving flight control instructions from a remote control device. Communications adapters implement the hardware level of data communications connections through which UAVs transmit wireless data communications. Examples of communications adapters include wireless modems for dial-up connections through wireless telephone networks. UAV (100) includes servos (178). Servos (178) are proportional control servos that convert digital control signals from system bus (160) into actual proportional displacement of flight control surfaces, ailerons, elevators, and the rudder. The displacement of flight control surfaces is ‘proportional’ to values of digital control signals, as opposed to the ‘all or nothing’ motion produced by some servos. In this way, ailerons, for example, may be set to thirty degrees, sixty degrees, or any other supported angle rather than always being only neutral or fully rotated. Several proportional control servos useful in various UAVs according to embodiments of the present invention are available from Futaba®. UAV (100) includes a servo control adapter (172). A servo control adapter (172) is multi-function input/output servo motion controller capable of controlling several servos. An example of such a servo control adapter is the “IOSERVO” model from National Control Devices of Osceola, Mo. The IOSERVO is described on National Control Devices website at www.controlanything.com. UAV (100) includes a flight stabilizer system (174). A flight stabilizer system is a control module that operates servos (178) to automatically return a UAV to straight and level flight, thereby simplifying the work that must be done by navigation algorithms. An example of a flight stabilizer system useful in various embodiments of UAVs according to the present invention is model Co-Pilot™ from FMA, Inc., of Frederick, Md. The Co-Pilot flight stabilizer system identifies a horizon with heat sensors, identifies changes in aircraft attitude relative to the horizon, and sends corrective signals to the servos (178) to keep the UAV flying straight and level. UAV (100) includes an AVCS gyro (176). An AVCS gryo is an angular vector control system gyroscope that provides control signal to the servos to counter undesired changes in attitude such as those caused by sudden gusts of wind. An example of an AVCS gyro useful in various UAVs according to the present invention is model GYA350 from Futaba®. Remote control devices according to embodiments of the present invention typically include automated computing machinery capable of receiving user selections of pixel on GUI maps, mapping the pixel to a waypoint location, receiving downlink telemetry including for example a starting position from a GPS receiver on the UAV, calculating a heading in dependence upon the starting position, the coordinates of the waypoint, and a navigation algorithm, identifying flight control instructions for flying the UAV on the heading, and transmitting the flight control instructions as uplink telemetry from the remote control device to the UAV. FIG. 3 is a block diagram of an exemplary remote control device showing relations among components that includes automated computing machinery. In FIG. 3, remote control device (161) includes a processor (164), also typically referred to as a central processing unit or ‘CPU.’ The processor may be a microprocessor, a programmable control unit, or any other form of processor useful according to the form factor of a particular remote control device as will occur to those of skill in the art. Other components of remote control device (161′ are coupled for data transfer to processor (164) through system bus (160). Remote control device (161) includes random access memory or ‘RAM’ (166). Stored in RAM (166) an application program 152 that implements inventive methods of the present invention. Among other things, application program (158) includes computer program instructions capable of navigating UAVs in formation according to embodiments of the present invention, including computer program steps that execute generally by assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, where the navigation algorithm includes repeatedly comparing the UAV's intended position and the UAV's actual position, the actual position taken from a GPS receiver, and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. This capability of navigating UAVs in formation is described in more detail below in this specification. In some embodiments, the application program (152) is OSGi compliant an therefore runs on an OSGi service framework installed (not shown) on a JVM (not shown). In addition, software programs and further information for use in implementing methods of navigating a UAV according to embodiments of the present invention may be stored in RAM or in non-volatile memory (168). Non-volatile memory (168) may be implemented as a magnetic disk drive such as a micro-drive, an optical disk drive, static read only memory (‘ROM’), electrically erasable programmable read-only memory space (‘EEPROM’ or ‘flash’ memory), or otherwise as will occur to those of skill in the art. Remote control device (161) includes communications adapter (170) implementing data communications connections (184) to other computers (162), including particularly computers on UAVs. Communications adapters implement the hardware level of data communications connections through which remote control devices communicate with UAVs directly or through networks. Examples of communications adapters include modems for wired dial-up connections, Ethernet (IEEE 802.3) adapters for wired LAN connections, 802.11b adapters for wireless LAN connections, and Bluetooth adapters for wireless microLAN connections. The example remote control device (161) of FIG. 3 includes one or more input/output interface adapters (180). Input/output interface adapters in computers implement user-oriented input/output through, for example, software drivers and computer hardware for controlling output to display devices (185) such as computer display screens, as well as user input from user input devices (182) such as keypads, joysticks, keyboards, and touch screens. FIG. 4 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving (402) in a remote control device a user's selection of a GUI map pixel (412) that represents a waypoint for UAV navigation. The pixel has a location on the GUI. Such a GUI map display has many pixels, each of which represents at least one position on the surface of the Earth. A user selection of a pixel is normal GUI operations to take a pixel location, row and column, from a GUI input/output adapter driven by a user input device such as a joystick or a mouse. The remote control device can be a traditional ‘ground control station,’ an airborne PDA or laptop, a workstation in Earth orbit, or any other control device capable of accepting user selections of pixels from a GUI map. The method of FIG. 4 includes mapping (404) the pixel's location on the GUI to Earth coordinates (414) of the waypoint. As discussed in more detail below with reference to FIG. 5, mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) typically includes mapping pixel boundaries of the GUI map to corresponding Earth coordinates and identifying a range of latitude and a range of longitude represented by each pixel. Mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) also typically includes locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map. The method of FIG. 4 also includes receiving (408) downlink telemetry, including a starting position from a GPS receiver on the UAV, from the UAV through a socket on the remote control device. In fact, the remote control device is receiving downlink telemetry that includes a steady stream of GPS positions of the UAV. Receiving a starting position therefore is typically carried out by taking the current position of the UAV when the user selects the pixel as the starting position. A socket is one end-point of a two-way communication link between two application programs running on a network. In Java, socket classes are used to represent a connection between a client program and a server program. The java.net package provides two Java classes—Socket and ServerSocket—that implement the client side of the connection and the server side of the connection, respectively. In some embodiments of the present invention, a Java web server, is included in an OSGi framework on a remote control device. Often then, a socket on the remote control device would be considered a server-side socket, and a socket on the UAV would be considered a client socket. In other embodiments of the present invention, a Java web server, is included in an OSGi framework on the UAV. In such embodiments, a socket on the UAV would be considered a server-side socket, and a socket on a remote control device would be considered a client socket. Use of a socket requires creating a socket and creating data streams for writing to and reading from the socket. One way of creating a socket and two data streams for use with the socket is shown in the following exemplary pseudocode segment: uavSocket=new Socket(“computerAddress”, 7); outStream=new PrintWriter(uavSocket.getOutputStream( ), true); inStream=new BufferedReader(new InputStreamReader(uavSocket.getInputStream( ))); The first statement in this segment creates a new socket object and names it “uavSocket.” The socket constructor used here requires a fully qualified IP address of the machine the socket is to connect to, in this case the Java server on a remote control device or a UAV, and the port number to connect to. In this example, “computerAddress” is taken as a domain name that resolves to a fully qualified dotted decimal IP address. Alternatively, a dotted decimal IP address may be employed directly, as, for example, “195.123.001.001.” The second argument in the call to the socket constructor is the port number. Port number 7 is the port on which the server listens in this example, whether the server is on a remote control device or on a UAV. The second statement in this segment gets the socket's output stream and opens a Java PrintWriter object on it. Similarly, the third statement gets the socket's input stream and opens a Java BufferedReader object on it. To send data through the socket, an application writes to the PrintWriter, as, for example: outStream.printIn(someWaypoint, macro, or Flight Control Instruction); To receive data through the socket, an application reads from the BufferedReader, as show here for example: a Waypoint, GPS data, macro, or flight control instruction=inStream.readLine( ); The method of FIG. 4 also includes calculating (410) a heading in dependence upon the starting position, the coordinates of the waypoint, and a navigation algorithm. Methods of calculating a heading are discussed in detail below in this specification. The method of FIG. 4 includes identifying (418) flight control instructions for flying the UAV on the heading. Flight control instructions are specific commands that affect the flight control surfaces of the UAV. That is, instructions to move the flight control surfaces to affect the UAV's flight causing the UAV to turn, climb, descend, and so on. As an aid to further explanation, an exemplary method of identifying flight control instructions for flying on a calculated heading is provided: receive new calculated heading from navigation algorithms read current heading from downlink telemetry if current heading is left of the calculated heading, identify flight control instruction: AILERONS LEFT 30 DEGREES if current heading is right of the calculated heading, identify flight control instruction: AILERONS RIGHT 30 DEGREES monitor current heading during turn when current heading matches calculated heading, identify flight control instruction: FLY STRAIGHT AND LEVEL The method of FIG. 4 includes transmitting (420) uplink telemetry, including the flight instructions, through the socket to the UAV. Transmitting (420) the flight control instructions from the remote control device to the UAV may be carried out by use of any data communications protocol, including, for example, transmitting the flight control instructions as form data, URI encoded data, in an HTTP message, a WAP message, an HDML message, or any other data communications protocol message as will occur to those of skill in the art. FIG. 4A is a data flow diagram illustrating an exemplary method for receiving downlink telemetry. The method of FIG. 4A includes listening (450) on the socket (456) for downlink data (458). Listening on a socket for downlink data may be implemented by opening a socket, creating an input stream for the socket, and reading data from the input stream, as illustrated, for example, in the following segment of pseudocode: uavSocket=new Socket(“computerAddress”, 7); inStream=new BufferedReader(new InputStreamReader(uavSocket.getInputStream( ))); String downLinkData=inStream.readLine( ); This segment opens a socket object named “uavSocket” with an input stream named “inStream.” Listening for downlink data on the socket is accomplished with a blocking call to in Stream.readLine( ) which returns a String object name “downLinkData.” The method of FIG. 4A includes storing (452) downlink data (458) in computer memory (166) and exposing (454) the stored downlink data (458) through an API (462) to a navigation application (460). Downlink data typically is exposed through an ‘API’ (Application Programming Interface) by providing in a Java interface class public accessor functions for reading from member data elements in which the downlink data is stored. A navigation application wishing to access downlink data then may access the data by calling a public accessor methods, as, for example: String someDownLinkData=APIimpl.getDownLinkData( ). In the method of FIG. 4A, the downlink telemetry (470) further comprises flight control instructions. It is counterintuitive that downlink telemetry contains flight control instruction when the expected data communications direction for flight control instructions ordinarily is in uplink from a remote control device to a UAV. It is useful to note, however, that flight control instructions can be uplinked from a multiplicity of remote control devices, not just one. A flight line technician with a handheld PDA can issue flight control instructions to a UAV that is also linked for flight control to a computer in a ground station. It is sometimes advantageous, therefore, for downlink telemetry to include flight control instructions so that one remote control device can be advised of the fact that some other remote control device issued flight control instructions to the same UAV. FIG. 4B sets forth a data flow diagram illustrating an exemplary method for transmitting uplink telemetry. The method of FIG. 4B includes monitoring (466) computer memory (166) for uplink data (464) from a navigation application (460). When uplink data (464) is presented, the method of FIG. 4B includes sending (468) the uplink data through the socket (456) to the UAV (100). Sending uplink data through a socket may be implemented by opening a socket, creating an output stream for a socket, and writing the uplink data to the output stream, as illustrated, for example, in the following segment of pseudocode: uavSocket=new Socket(“computerAddress”, 7); outStream=new PrintWriter(uavSocket.getOutputStream( ), true); outStream.printIn(String someUplinkData); This segment opens a socket object named “uavSocket” with an output stream named “outStream.” Sending uplink data through the socket is accomplished with a call to outStream.printIn( ) which takes as a call parameter a String object named “someUplinkData.” Macros Although the flow chart of FIG. 4 illustrates navigating a UAV to a single waypoint, as a practical matter, embodiments of the present invention typically support navigating a UAV along a route having many waypoints, including a final waypoint and one or more intermediate waypoints. That is, methods of the kind illustrated in FIG. 4 may also include receiving user selections of a multiplicity of GUI map pixels representing waypoints, where each pixel has a location on the GUI and mapping each pixel location to Earth coordinates of a waypoint. Such methods for navigating a UAV can also include assigning one or more UAV instructions to each waypoint and storing the coordinates of the waypoints and the UAV instructions in computer memory on the remote control device. A UAV instruction typically includes one or more instructions for a UAV to perform a task in connection with a waypoint. Exemplary tasks include turning on or off a camera installed on the UAV, turning on or off a light installed on the UAV, orbiting a waypoint, or any other task that will occur to those of skill in the art. UAV instructions to perform tasks in connection with a waypoint may be encoded in, for example, XML (the eXtensible Markup Language) as shown in the following exemplary XML segment: <UAV-Instructions> <macro> <waypoint> 33° 44′ 10″ N 30° 15′ 50″ W </waypoint> <instruction> orbit </instruction> <instruction> videoCameraON </instruction> <instruction> wait30minutes </instruction> <instruction> videoCameraOFF </instruction> <instruction> nextWaypoint </instruction> </macro> <macro> </macro> <macro> </macro> <macro> </macro> <UAV-instructions> This XML example has a root element named ‘UAV-instructions.’ The example contains several subelements named ‘macro.’ One ‘macro’ subelement contains a waypoint location representing an instruction to fly to 33° 44′ 10″ N 30° 15′ 50″ W. That macro subelement also contains several instructions for tasks to be performed when the UAV arrives at the waypoint coordinates, including orbiting around the waypoint coordinates, turning on an on-board video camera, continuing to orbit for thirty minutes with the camera on, turning off the video camera, and continuing to a next waypoint. Only one macro set of UAV instructions is shown in this example, but that is not a limitation of the invention. In fact, such sets of UAV instructions may be of any useful size as will occur to those of skill in the art. Exemplary methods of navigating a UAV also include flying the UAV to each waypoint in accordance with one or more navigation algorithms and operating the UAV at each waypoint in accordance with the UAV instructions for each waypoint. Operating the UAV at the waypoint in accordance with the UAV instructions for each waypoint typically includes identifying flight control instructions in dependence upon the UAV instructions for each waypoint and transmitting the flight control instructions as uplink telemetry through a socket. Flight control instructions identified in dependence upon the UAV instructions for each waypoint typically include specific flight controls to move the flight control surfaces of the UAV causing the UAV to fly in accordance with the UAV instructions. For example, in the case of a simple orbit, a flight control instruction to move the ailerons and hold them at a certain position causing the UAV to bank at an angle can effect an orbit around a waypoint. Operating the UAV at the waypoint in accordance with the UAV instructions for each waypoint typically includes transmitting the flight control instructions as uplink data from the remote control device to the UAV. Transmitting the flight control instructions as uplink data from the remote control device to the UAV may be carried out by use of any data communications protocol, including, for example, transmitting the flight control instructions as form data, URI encoded data, in an HTTP message, a WAP message, an HDML message, or any other data communications protocol message as will occur to those of skill in the art. Pixel Mapping For further explanation of the process of mapping pixels' locations to Earth coordinates, FIG. 5 sets forth a block diagram that includes a GUI (502) displaying a map (not shown) and a corresponding area of the surface of the Earth (504). The GUI map has pixel boundaries identified as Row1, Col1; Row1, Col100; Row100, Col100; and Row100, Col1. In this example, the GUI map is assumed to include 100 rows of pixels and 100 columns of pixels. This example of 100 rows and columns is presented for convenience of explanation; it is not a limitation of the invention. GUI maps according to embodiments of the present invention may include any number of pixels as will occur to those of skill in the art. The illustrated area of the surface of the Earth has corresponding boundary points identified as Lat1, Lon1; Lat1, Lon2; Lat2, Lon2; and Lat2, Lon1. This example assumes that the distance along one side of surface area (504) is 100 nautical miles, so that the distance expressed in terms of latitude or longitude between boundary points of surface area (504) is 100 minutes or 1° 40′. In typical embodiments, mapping a pixel's location on the GUI to Earth coordinates of a waypoint Includes mapping pixel boundaries of the GUI map to Earth coordinates. In this example, the GUI map boundary at Row1, Col1 maps to the surface boundary point at Lat1, Lon1; the GUI map boundary at Row1, Col2 maps to the surface boundary point at Lat1, Lon2; the GUI map boundary at Row2, Col2 maps to the surface boundary point at Lat2, Lon2; the GUI map boundary at Row2, Col1 maps to the surface boundary point at Lat2, Lon1. Mapping a pixel's location on the GUI to Earth coordinates of a waypoint typically also includes identifying a range of latitude and a range of longitude represented by each pixel. The range of latitude represented by each pixel may be described as (Lat2-Lat1)/Nrows, where (Lat2−Lat1) is the length in degrees of the vertical side of the corresponding surface (504), and Nrows is the number of rows of pixels. In this example, (Lat2−Lat1) is 1° 40′ or 100 nautical miles, and Nrows is 100 rows of pixels. The range of latitude represented by each pixel in this example therefore is one minute of arc or one nautical mile. Similarly, the range of longitude represented by each pixel may be described as (Lon2-Lon1)/Ncols, where (Lon2−Lon1) is the length in degrees of the horizontal side of the corresponding surface (504), and Ncols is the number of columns of pixels. In this example, (Lon2−Lon1) is 1° 40 or 100 nautical miles, and Ncols is 100 columns of pixels. The range of longitude represented by each pixel in this example therefore is one minute of arc or one nautical mile. Mapping a pixel's location on the GUI to Earth coordinates of a waypoint typically also includes locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map. The region is the portion of the surface corresponding to the pixel itself. That region is located generally by multiplying in both dimensions, latitude and longitude, the range of latitude and longitude by column or row numbers of the pixel location on the GUI map. That is, a latitude for the surface region of interest is given by Expression 1. Lat1+Prow((Lat2−Lat1)/Nrows) (Exp. 1) In Expression 1: Lat1 is the latitude of an origin point for the surface area (504) corresponding generally to the GUI map, Prow is the row number of the pixel location on the GUI map, and ((Lat2−Lat1)/Nrows) is the range of latitude represented by the pixel. Similarly, a longitude for the surface region of interest is given by Expression 2. Lon1+Pcol((Lon2−Lon1)/Ncols) (Exp. 2) In Expression 2: Lon1 is the longitude of an origin point for the surface area (504) corresponding generally to the GUI map, Pcol is the column number of the pixel location on the GUI map, and ((Lon2−Lon1)/Ncols) is the range of longitude represented by the pixel. Referring to FIG. 5 for further explanation, Expressions 1 and 2 taken together identify a region (508) of surface area (504) that corresponds to the location of pixel (412) mapping the pixel location to the bottom left corner (506) of the region (508). Advantageously, however, many embodiments of the present invention further map the pixel to the center of the region by adding one half of the length of the region's sides to the location of the bottom left corner (506). More particularly, locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map, as illustrated by Expression 3, may include multiplying the range of longitude represented by each pixel by a column member of the selected pixel, yielding a first multiplicand; and multiplying the range of longitude represented by each pixel by 0.5, yielding a second multiplicand; adding the first and second multiplicands to an origin longitude of the GUI map. Lon1+Pcol((Lon2−Lon1)/Ncols)+0.5((Lon2−Lon1)/Ncols) (Exp. 3) In Expression 3, the range of longitude represented by each pixel is given by ((Lon2−Lon1)/Ncols), and the first multiplicand is Pcol((Lon2−Lon1)/Ncols). The second multiplicand is given by 0.5((Lon2−Lon1)/Ncols). Similarly, locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map, as illustrated by Expression 4, typically also includes multiplying the range of latitude represented by each pixel by a row number of the selected pixel, yielding a third multiplicand; multiplying the range of latitude represented by each pixel by 0.5, yielding a fourth multiplicand; and adding the third and fourth multiplicands to an origin latitude of the GUI map. Lat1+Prow((Lat2−Lat1)/Nrows)+0.5((Lat2−Lat1)/Nrows) (Exp. 4) In Expression 4, the range of latitude represented by each pixel is given by ((Lat2−Lat1)/Nrows), and the third multiplicand is Prow((Lat2−Lat1)/Nrows). The fourth multiplicand is given by 0.5((Lat2−Lat1)/Nrows). Expressions 3 and 4 taken together map the location of pixel (412) to the center (510) of the located region (508). Navigation on a Heading to a Waypoint An exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 6 and 7. FIG. 6 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm, and FIG. 7 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 6. The method of FIG. 6 includes periodically repeating (610) the steps of, receiving (602) in the remote control device from the GPS receiver a current position of the UAV, and calculating (604) a new heading from the current position to the waypoint. The method of FIG. 6 also includes identifying (606) flight control instructions for flying the UAV on the new heading, and transmitting (608), from the remote control device to the UAV, the flight control instructions for flying the UAV on the new heading. In this method, if Lon1, Lat1 is taken as the current position, and Lon2, Lat2 is taken as the waypoint position, then the new heading may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). FIG. 7 shows the effect of the application of the method of FIG. 6. In the example of FIG. 7, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (716) results from periodic calculations according to the method of FIG. 6 of a new heading straight from a current location to the waypoint. FIG. 7 shows periodic repetitions of the method of FIG. 6 at plot points (710, 712, 714). For clarity of explanation, only three periodic repetitions are shown, although that is not a limitation of the invention. In fact, any number of periodic repetitions may be used as will occur to those of skill in the art. Navigation with Headings set to a Cross Track Direction A further exemplary method of navigating in accordance with a navigation algorithm explained with reference to FIGS. 8 and 9. FIG. 8 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm, and FIG. 9 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 8. The method of FIG. 8 includes identifying (802) a cross track between the starting point and the waypoint. A cross track is a fixed course from a starting point directly to a waypoint. If Lon1, Lat1 is taken as the position of a starting point, and Lon2, Lat2 is taken as the waypoint position, then a cross track is identified by Lon1, Lat1 and Lon2, Lat2. A cross track has a direction, a ‘cross track direction,’ that is the direction straight from a starting point to a waypoint, and it is often useful to characterize a cross track by its cross track direction. The cross track direction for a cross track identified by starting point Lon1, Lat1 and waypoint position Lon2, Lat2 may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). The method of FIG. 8 includes periodically repeating (810) the steps of receiving (804) in the remote control device from the GPS receiver a current position of the UAV, and calculating (806) a shortest distance between the current position and the cross track. If the shortest distance between the current position and the cross track is greater than a threshold distance (808), the method of FIG. 8 includes transmitting (812) flight control instructions that pilot the UAV toward the cross track, and, when the UAV arrives at the cross track, transmitting (814) flight control instructions that pilot the UAV in a cross track direction toward the waypoint. FIG. 9 illustrates calculating a shortest distance between the current position and a cross track. In the example of FIG. 9, calculating a shortest distance between the current position and a cross track includes calculating the distance from a current position (912) to the waypoint (704). In the example of FIG. 9, the distance from the current position (912) to the waypoint (704) is represented as the length of line (914). For current position Lon1, Lat1 and waypoint position Lon2, Lat2, the distance from a current position (912) to the waypoint (704) is given by the square root of (Lat2−Lat1)2+(Lon2−Lon1)2. In this example, calculating a shortest distance between the current position and a cross track also includes calculating the angle (910) between a direction from the current position (912) to the waypoint (704) and a cross track direction. In the example of FIG. 9, the direction from the current position (912) to the waypoint (704) is represented as the direction of line (914). In the example of FIG. 9, the cross track direction is the direction of cross track (706). The angle between a direction from the current position to the waypoint and a cross track direction is the difference between those directions. In the current example, calculating a shortest distance between the current position and a cross track also includes calculating the tangent of the angle between a direction from the current position to the waypoint and a cross track direction and multiplying the tangent of the angle by the distance from the current position to the waypoint. FIG. 9 also shows the effect of the application of the method of FIG. 8. In the example of FIG. 9, a UAV is flying in a cross wind having cross wind vector (708). The flight path (904) results from periodic calculations according to the method of FIG. 8 of a shortest distance between a current position and the cross track (706), flying the UAV back to the cross track and then flying in the direction of the cross track whenever the distance from the cross track exceeds a predetermined threshold distance (916). Headings Set to Cross Track Direction with Angular Thresholds A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 10 and 11. FIG. 10 sets forth a flow chart illustrating an exemplary method of navigating a UAV in accordance with a navigation algorithm, and FIG. 11 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 10. In the method of FIG. 10, piloting in accordance with a navigation algorithm includes identifying (1002) a cross track having a cross track direction between the starting point and the waypoint. As described above, a cross track is identified by a position of a starting point and a waypoint position. For a starting point position of Lon1, Lat1 and a waypoint position of Lon2, Lat2, a cross track is identified by Lon1, Lat1 and Lon2, Lat2. In addition, it is often also useful to characterize a cross track by its cross track direction. The cross track direction for a cross track identified by starting point Lon1, Lat1 and waypoint position Lon2, Lat2 may be calculated generally as the inverse tangent of ((Lat2−Lat1)/(Lon2−Lon1)). In the method of FIG. 10, navigating a UAV in accordance with a navigation algorithm includes periodically repeating (1010) the steps of receiving (1004) in the remote control device from the GPS receiver a current position and a current heading of the UAV, and calculating (1006) an angle between the direction from the current position to the waypoint and a cross track direction. If the angle is greater than a threshold angle (1008), the method of FIG. 10 includes transmitting (1012) flight control instructions that pilot the UAV toward the cross track, and, upon arriving at the cross track, transmitting (1014) flight control instructions that pilot the UAV in the cross track direction toward the waypoint. Transmitting (1012) flight control instructions that pilot the UAV toward the cross track is carried out by transmitting flight control instructions to turn to a heading no more than ninety degrees from the cross track direction, turning to the left if the current position is right of the cross track and to the right if the current position is left of the cross track. Transmitting (1014) flight control instructions that pilot the UAV in the cross track direction toward the waypoint transmitting flight control instructions to turn the UAV to the cross track direction and then flying straight and level on the cross track direction. FIG. 11 shows the effect of the application of the method of FIG. 10. In the example of FIG. 1, a UAV is flying in a cross wind having cross wind vector (708). The flight path (1104) results from periodically transmitting flight control instructions to fly the UAV, according to the method of FIG. 10, back to the cross track and then in the direction of the cross track whenever an angle between the direction from the current position to the waypoint and a cross track direction exceeds a predetermined threshold angle. In many embodiments of the method of FIG. 10, the threshold angle is a variable whose value varies in dependence upon a distance between the UAV and the waypoint. In typical embodiments that vary the threshold angle, the threshold angle is increased as the UAV flies closer to the waypoint. It is useful to increase the threshold angle as the UAV flies closer to the waypoint to reduce the risk of excessive ‘hunting.’ That is, because the heading is the cross track direction, straight to the WP rather than cross wind, if the angle remains the same, the distance that the UAV needs to be blown off course to trigger transmitting flight control signals instructing the UAV to return to the cross track gets smaller and smaller until the UAV is flying to the cross track, turning to the cross track direction, getting blown immediately across the threshold, flying back the cross track, turning to the cross track direction, getting blown immediately across the threshold, and so on, and so on, in rapid repetition. Increasing the threshold angle as the UAV flies closer to the waypoint increases the lateral distance available for wind error before triggering the transmission of flight instructions to return to the cross track, thereby reducing this risk of excessive hunting. FIG. 12 sets forth a flow chart illustrating an exemplary method for navigating a UAV that includes receiving (402) in a remote control device a user's selection of a GUI map pixel (412) that represents a waypoint for UAV navigation. The pixel has a location on the GUI. Such a GUI map display has many pixels, each of which represents at least one position on the surface of the Earth. A user selection of a pixel is normal GUI operations to take a pixel location, row and column, from a GUI input/output adapter driven by a user input device such as a joystick or a mouse. The remote control device can be a traditional ‘ground control station,’ an airborne PDA or laptop, a workstation in Earth orbit, or any other control device capable of accepting user selections of pixels from a GUI map. The method of FIG. 12 includes mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414). As discussed in more detail above with reference to FIG. 5, mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) typically includes mapping pixel boundaries of the GUI map to corresponding Earth coordinates and identifying a range of latitude and a range of longitude represented by each pixel. Mapping (404) the pixel's location on the GUI to Earth coordinates of the waypoint (414) also typically includes locating a region on the surface of the Earth in dependence upon the boundaries, the ranges, and the location of the pixel on the GUI map. The method of FIG. 12 also includes transmitting (406) uplink telemetry, including the coordinates of the waypoint, to the UAV through a socket on the remote control device. Transmitting (406) uplink telemetry, including the coordinates of the waypoint, to the UAV through a socket on the remote control device may be carried out by use of any data communications protocol, including, for example, transmitting the coordinates as form data, URI encoded data, in an HTTP message, a WAP message, an HDML message, or any other data communications protocol message as will occur to those of skill in the art. Transmitting uplink telemetry through a socket may be implemented by opening a socket, creating an output stream for the socket, and writing uplink telemetry data to the output stream, as illustrated, for example, in the following segment of pseudocode: uavSocket=new Socket(“computerAddress”, 7); outStream=new PrintWriter(uavSocket.getOutputStream( ), true); outStream.printIn(String someUplinkData); This segment opens a socket object named “uavSocket” with an output stream named “outStream.” Transmitting uplink telemetry through the socket is accomplished with a call to outStream.printIn( ) which takes as a call parameter a String object named “someUplinkData.” The method of FIG. 12 also includes receiving (408) downlink telemetry, including a starting position from a GPS receiver, from the UAV through the socket and piloting (410) the UAV, under control of a navigation computer on the UAV, from the starting position to the waypoint in accordance with a navigation algorithm. Methods of piloting a UAV according to a navigation algorithm are discussed in detail below in this specification. Receiving downlink telemetry through a socket may be implemented by opening a socket, creating an input stream for the socket, and reading data from the input stream, as illustrated, for example, in the following segment of pseudocode: uavSocket=new Socket(“computerAddress”, 7); inStream=new BufferedReader(new InputStreamReader(uavSocket.getInputStream( ))); String downLinkTelemetry=inStream.readLine( ); This segment opens a socket object named “uavSocket” with an input stream named “inStream.” Receiving downlink telemetry through the socket is accomplished with a blocking call to in Stream.readLine( ) which returns a String object name “downLinkTelemetry.” In the method of FIG. 12, downlink telemetry may include Earth coordinates of waypoints as well as one or more UAV instructions. It is counterintuitive that downlink telemetry contains waypoint coordinates and UAV instructions when the expected data communications direction for waypoint coordinates and UAV instructions ordinarily is in uplink from a remote control device to a UAV. It is useful to note, however, that waypoint coordinates and UAV instructions can be uplinked from a multiplicity of remote control devices, not just one. A flight line technician with a handheld PDA can issue waypoint coordinates and UAV instructions to a UAV that is also linked for flight control to a computer in a ground station. It is sometimes advantageous, therefore, for downlink telemetry to include waypoint coordinates or UAV instructions so that one remote control device can be advised of the fact that some other remote control device issued waypoint coordinates or UAV instructions to the same UAV. Macros As mentioned above, embodiments of the present invention often support navigating a UAV along a route having many waypoints, including a final waypoint and one or more intermediate waypoints. That is, methods of the kind illustrated in FIG. 12 may also include receiving user selections of a multiplicity of GUI map pixels representing waypoints, where each pixel has a location on the GUI and mapping each pixel location to Earth coordinates of a waypoint. Such methods of navigating a UAV can also include assigning one or more UAV instructions to each waypoint and transmitting the coordinates of the waypoints and the UAV instructions in the uplink telemetry through the socket to the UAV. A UAV instruction typically includes one or more instructions for a UAV to perform a task in connection with a waypoint. Exemplary tasks include turning on or off a camera installed on the UAV, turning on or off a light installed on the UAV, orbiting a waypoint, or any other task that will occur to those of skill in the art. Such exemplary methods of navigating a UAV also include storing the coordinates of the waypoints and the UAV instructions in computer memory on the UAV, piloting the UAV to each waypoint in accordance with one or more navigation algorithms, and operating the UAV at each waypoint in accordance with the UAV instructions for each waypoint. Navigation on a Course to a Waypoint A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 13, 14, and 15. FIG. 13 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm. FIG. 14 sets forth a line drawing illustrating a method of calculating a heading with a cross wind to achieve a particular ground course. And FIG. 15 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 13. In the method of FIG. 13, piloting in accordance with a navigation algorithm comprises periodically repeating (1212) the steps of reading (1202) from the GPS receiver a current position of the UAV; calculating (1204) a direction to the waypoint from the current position; calculating (1206) a heading in dependence upon wind speed, wind direction, airspeed, and the direction to the waypoint; turning (1208) the UAV to the heading; and flying (1210) the UAV on the heading. FIG. 14 illustrates calculating a heading in dependence upon wind speed, wind direction, airspeed, and the direction to the waypoint. FIG. 14 sets forth a line drawing illustrating relations among several pertinent vectors, a wind velocity (1222), a resultant velocity (1224), and a UAV's air velocity (1226). A velocity vector includes a speed and a direction. These vectors taken together represent wind speed, wind direction, airspeed, and the direction to the waypoint. In the example of FIG. 14, the angle B is a so-called wind correction angle, an angle which subtracted from (or added to, depending on wind direction) a direction to a waypoint yields a heading, a compass heading for a UAV to fly so that its resultant ground course is on a cross track. A UAV traveling at an airspeed of ‘a’ on heading (D−B) in the presence of a wind speed ‘b’ with wind direction E will have resultant groundspeed ‘c’ in direction D. In FIG. 14, angle A represents the difference between the wind direction E and the direction to the waypoint D. In FIG. 14, the wind velocity vector (1222) is presented twice, once to show the wind direction as angle E and again to illustrate angle A as the difference between angles E and D. Drawing wind velocity (1222) to form angle A with the resultant velocity (1224) also helps explain how to calculate wind correction angle B using the law of sines. Knowing two sides of a triangle and the angle opposite one of them, the angle opposite the other may be calculated, in this example, by B=sin−1(b (sin A)/a). The two known sides are airspeed ‘a’ and wind speed ‘b.’ The known angle is A, the angle opposite side ‘a,’ representing the difference between wind direction E and direction to the waypoint D. Calculating a heading, angle F on FIG. 14, is then carried out by subtracting the wind correction angle B from the direction to the waypoint D. FIG. 15 shows the effect of the application of the method of FIG. 13. In the example of FIG. 15, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (1316) results from periodic calculations according to the method of FIG. 13 of a new heading straight whose resultant with a wind vector is a course straight from a current location to the waypoint. FIG. 15 shows periodic repetitions of the method of FIG. 13 at plot points (1310, 1312, 1314). For clarity of explanation, only three periodic repetitions are shown, although that is not a limitation of the invention. In fact, any number of periodic repetitions may be used as will occur to those of skill in the art. Navigation on a Course Set to a Cross Track Direction A further exemplary method of navigating in accordance with a navigation algorithm is explained with reference to FIGS. 16 and 17. FIG. 16 sets forth a flow chart illustrating an exemplary method of piloting in accordance with a navigation algorithm, and FIG. 17 sets forth a line drawing illustrating a flight path produced by application of the method of FIG. 16. The method of FIG. 16 includes identifying (1402) a cross track and calculating (1404) a cross track direction from the starting position to the waypoint. In the method of FIG. 16, piloting in accordance with a navigation algorithm is carried out by periodically repeating the steps of reading (1406) from the GPS receiver a current position of the UAV; calculating (1408) a shortest distance between the cross track and the current position; and, if the shortest distance between the cross track and the current position is greater than a threshold distance, piloting (1412) the UAV to the cross track. Upon arriving at the cross track, the method includes: reading (1414) from the GPS receiver a new current position of the UAV; calculating (1416), in dependence upon wind speed, wind direction, airspeed, and the cross track direction, a new heading; turning (1418) the UAV to the new heading (1502, 1505, and 1506); and flying (1420) the UAV on the new heading. FIG. 17 shows the effect of the application of the method of FIG. 16. In the example of FIG. 17, a UAV is flying in a cross wind having cross wind vector (708). Curved flight path (1504) results from periodic calculations according to the method of FIG. 16 of a shortest distance between a current position and the cross track (706), flying the UAV back to the cross track, and, upon arriving at the cross track, calculating a new heading and flying the UAV on the new heading. Navigating UAVs in Formation It is also advantageous to have an ability to navigate UAVs together in a flight formation or pattern. Exemplary methods, systems, and products for navigating UAVs together in a flight formation or pattern are described with reference to the accompanying drawings, beginning with FIGS. 18, 19A, and 19B. FIG. 18 sets forth a flow chart illustrating an exemplary method for navigating UAVs in formation. FIGS. 19A and 19B are line drawings illustrating exemplary relations among UAVs flying in formation. The method of FIG. 18 includes assigning (302) pattern positions to each of a multiplicity of UAVs flying together in a pattern. The examples of FIGS. 19A and 19B includes two exemplary flight patterns for UAVs. FIG. 19A illustrates a pattern having two pattern positions occupied by UAV (226) and UAV (100). FIG. 19B illustrates a pattern having four pattern positions occupied by UAVs (226, 100, 234, and 142). Assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern may be carried out by designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position. In the pattern of FIG. 19A, for example, the pattern position occupied by UAV (226) may be designated an anchor position and UAV (100) may be assigned to a pattern position one mile to the right of the position of UAV (226). Similarly in the pattern of FIG. 19B, the position of the pattern position occupied by UAV (226) may be designated an anchor position and: UAV (100) may be assigned to a pattern position one mile to the right of the position of UAV (226), UAV (234) may be assigned to a pattern position one mile behind the position of UAV (226), and UAV (142) may be assigned to a pattern position one mile to the right and one mile behind the position of UAV (226). The method of FIG. 18 also includes identifying (304) a waypoint for each UAV in dependence upon the UAV's pattern position. Identifying a waypoint for each UAV in dependence upon its pattern position may be carried out by designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. In the pattern of FIG. 19A, for example, the pattern position occupied by UAV (226) may be designated an anchor position and assigned the waypoint (230). If UAV (100) is assigned to a pattern position one mile to the right of the position of UAV (226), a waypoint (210) is calculated for UAV (100) as one mile to the right of the waypoint (230) assigned to the anchor position. Similarly, if in the pattern of FIG. 19B: the position of the pattern position occupied by UAV (226) is designated an anchor position and assigned the waypoint (230), UAV (100) is assigned to a pattern position one mile to the right of the position of UAV (226), UAV (234) is assigned to a pattern position one mile behind the position of UAV (226), and UAV (142) is assigned to a pattern position one mile to the right and one mile behind the position of UAV (226), then: waypoint (210) is calculated for UAV (100) as one mile to the right of the waypoint (230) assigned to the anchor position, waypoint (238) is calculated for UAV (234) as one mile behind the waypoint (230) assigned to the anchor position, and waypoint (248) is calculated for UAV (142) as one mile to the right and one mile behind the waypoint (230) assigned to the anchor position. The method of FIG. 18 also includes piloting (306) the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm (312). The method of FIG. 18 also includes an exemplary navigation algorithm that is implemented to repeatedly compare (308) the UAV's intended position and the UAV's actual position. In this example, the actual position is taken from a GPS receiver on board the UAV. Each UAV's intended position may be specified by the UAV's position in the pattern, a cross track to the UAV's waypoint, and a flight schedule. The intended position is a conceptual position, an ideal used to navigate UAVs in formation. The intended position is the position on the cross track where the UAV would be if it flew precisely on schedule directly along the cross track. A flight schedule is a time limitation upon travel from a starting point to a waypoint. A flight schedule may be established by assigning an arrival time at the waypoints of the pattern, from which a groundspeed may be inferred. Or a flight schedule may be established by assigning a groundspeed for the formation, from which an arrival time can be inferred. Either way, the schedule established an intended position for the formation for every moment of the flight. If the groundspeed is taken as the governing parameter, then the arrival time is the groundspeed multiplied by the distance between the starting point and the waypoint. If the arrival time is taken as the governing parameter, then the groundspeed is the distance between the starting point and the waypoint divided by the difference between the arrival time and the start time. Either way, the groundspeed is known and the intended position of the pattern at any point in time is the groundspeed multiplied by the time elapsed after the start time. Similarly, for each UAV in a pattern, the UAV's intended position at any point of time elapsed after the start time is a position on a cross track where the UAV would be if the UAV's course were directly over the cross track at that point in time. The exemplary UAVs of FIGS. 19A and 19B are shown flying directly over their cross tracks. As a practical matter, actual flight courses are rarely directly over cross tracks. Nevertheless, for flying in formation, a course for each UAV that approximates a cross track is adequate if a UAV's actual position in its actual course does not vary too much from its intended position. What is ‘too much’ is defined by an error threshold. The navigation algorithm of FIG. 18 includes calculating (310) a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. Calculating a corrective flight vector is explained in more detail below. Piloting UAVs in dependence upon a navigation algorithm, together in a flight formation or pattern, usefully includes startup and continuation of normal flight to UAV waypoints, that is, flight when a UAV is within its error threshold. An exemplary algorithm for such flight is described with reference to FIGS. 20 and 21. FIG. 20 sets forth a flow chart illustrating an exemplary method of piloting the UAVs in dependence upon a navigation algorithm. FIG. 21 sets forth a line drawing illustrating an exemplary method of calculating airspeed and heading according to the method of FIG. 21. FIG. 20 sets forth a flow chart illustrating an exemplary method of piloting the UAVs in dependence upon a navigation algorithm that includes identifying (340) a cross track to a waypoint for each UAV, where the cross track has a cross track direction. In FIG. 21, cross track (212) has cross track direction indicated by angle D. The method of FIG. 20 includes piloting (342) the UAV to a starting point on the cross track. (222 on FIG. 21). In subsequent iterations, the method may be implemented any time the UAV returns to the cross track by moving the starting point to the point where the UAV returns to the cross track. The method of FIG. 20 includes calculating (344) an airspeed for flying from the starting point to the waypoint on schedule. The airspeed may be calculated from the wind speed, the groundspeed, and the angle between the wind direction and the ground course direction by use of the law of cosines according to the formula: a=√{square root over (b2+c2−2ab cos A)}, where: a is the airspeed needed for flying from the starting point to the waypoint on schedule, indicated on FIG. 21 as the length (280) of the flight vector (250), b is the wind speed, indicated on FIG. 21 as the length (282) of the wind vector (208), c is the course groundspeed for flying from the starting point to the waypoint on schedule, indicated on FIG. 21 as the length (284) of the course vector (212), and A is the angular difference between the wind direction and the ground course direction along the cross track, indicated on FIG. 21 as the angle ‘A.’ The wind direction is indicated on FIG. 21 as the angle E, and the ground course direction along the cross track is indicated on FIG. 21 as the angle D. The method of FIG. 20 includes calculating (346) a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction. The heading may be so calculated by use of the law of sines according to the formula: B=sin−1(b(sin A)/a), where: B is the wind correction angle, which in combination with a direction to a waypoint yields a heading, indicated on FIG. 21 as angle ‘F,’ b is the wind speed, indicated on FIG. 21 as the length (282) of the wind vector (208), A is the angular difference between the wind direction and the ground course direction along the cross track, indicated on FIG. 21 as the angle ‘A,’ and a is the airspeed needed for flying from the starting point to the waypoint on schedule, calculated by use of the law of cosines as described above, and indicated on FIG. 21 as the length (280) of the flight vector (250). Having the wind correction angle B, calculating the heading, angle F on FIG. 21, is then carried out by subtracting the wind correction angle B from the direction to the waypoint D. The method of FIG. 23) includes flying (348) the UAV on the heading at the airspeed. That is, starting from a starting point on the cross track and flying a heading and airspeed so calculated, results in a ground course that approximates the cross track direction. Calculating a corrective flight vector is further explained with reference to FIGS. 22, 23, and 24. FIG. 22 sets forth a flow chart illustrating an exemplary method of calculating a corrective flight vector. FIG. 23 is a line drawing illustrating application of the method of FIG. 22, showing relations among an intended position, an error threshold, an actual position, a corrective flight vector, and a cross track to a waypoint. FIG. 24 sets forth a line drawing illustrating an exemplary method of calculating corrective airspeed and corrective heading according to the method of FIG. 22. As mentioned above, an actual flight course is rarely directly over a cross track. For flying in formation, a course for each UAV that approximates a cross track is adequate if a UAV's actual position in its actual course does not vary too much from its intended position. What is ‘too much’ is defined by an error threshold. The navigation algorithm of FIG. 18 includes calculating (310) a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. FIG. 23 shows a UAV whose actual position (218) is outside an error threshold (202) around the UAV's intended position (220). That is, for this exemplary UAV, the distance (290) between the UAV's actual (218) and intended (220) positions exceeds an error threshold (202). The method of FIG. 22 includes selecting (360) a corrective waypoint (214) on FIG. 23) on a cross track (212) between a UAV's intended position (220) and its waypoint (210). Selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint may be carried out by selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. In the example of FIG. 23, a corrective waypoint (214) on a cross track (212) between a UAV's intended position (220) and its waypoint (210) is selected as a corrective waypoint at the predetermined portion of one-half of the distance between the UAV's intended position and its waypoint. The method of FIG. 22 also includes calculating (362) a corrective airspeed for arriving at the corrective waypoint on schedule. Calculating a corrective airspeed for arriving at the corrective waypoint on schedule may include calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule. Calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule may be carried out by dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. The schedule time for the corrective waypoint is the time when the UAV would reach the corrective waypoint if the UAV's ground course were over the cross track. With the groundspeed to the remedial waypoint known, calculating a corrective airspeed for arriving at the corrective waypoint on schedule may be calculated from the wind speed, the groundspeed to the remedial waypoint, and the angle between the wind direction and the ground course to the corrective waypoint by use of the law of cosines according to the formula: a=√{square root over (b2+c2−2ab cos A)}, where: a is the corrective airspeed for arriving at the corrective waypoint on schedule, indicated on FIG. 24 as the length (292) of the corrective flight vector (204), b is the wind speed, indicated on FIG. 24 as the length (294) of the wind vector (208), c is the groundspeed to the remedial waypoint, indicated on FIG. 24 as the length (296) of the ground course to the corrective waypoint (216), and A is the angular difference between the wind direction and the ground course direction to the corrective waypoint, indicated on FIG. 24 as the angle ‘A.’ The wind direction is indicated on FIG. 24 as the angle E, and the ground course direction to the corrective waypoint is indicated on FIG. 24 as the angle D. The method of FIG. 22 includes also calculating (364) a corrective heading in dependence upon the calculated airspeed. The corrective heading may be so calculated by use of the law of sines according to the formula: B=sin−1(b(sin A)/a), where: B is the wind correction angle, which in combination with a direction to a corrective waypoint yields a heading, indicated on FIG. 24 as angle ‘B,’ b is the wind speed, indicated on FIG. 24 as the length (294) of the wind vector (208), A is the angular difference between the wind direction and the ground course to the corrective waypoint, indicated on FIG. 24 as the angle ‘A,’ and a is the airspeed needed to fly from the actual position (218) to the corrective waypoint so as to arrive at the corrective waypoint on schedule, calculated by use of the law of cosines as described above, and indicated on FIG. 24 as the length (292) of the corrective flight vector (204). Having the wind correction angle B, calculating the corrective heading, angle F on FIG. 24, is then carried out by subtracting the wind correction angle B from the direction to the corrective waypoint D. Upon arriving at the corrective waypoint (214), the UAV may be piloted by the method of FIG. 20, for example, on a heading and with an airspeed calculated to fly a course along a cross track (212 on FIG. 23) and arrive at its waypoint on schedule. All the navigational calculations for navigating UAVs in formation according to embodiments of the present invention may be carried in computers located either in the UAVs or in one or more ground stations. In systems that carry out navigational calculations in a UAV, uplink telemetry may provide starting points, waypoints, and other flight parameters to the UAV, and downlink telemetry may provide GPS locations for the UAV to the ground station. In systems that carry out navigational calculations in ground stations, downlink telemetry may provide GPS locations, and uplink telemetry may provide flight control instructions. It will be understood from the foregoing description that modifications and changes may be made in various embodiments of the present invention without departing from its true spirit. The descriptions in this specification are for purposes of illustration only and are not to be construed in a limiting sense. The scope of the present invention is limited only by the language of the following claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>1. Field of the Invention The field of the invention is data processing, or, more specifically, methods, systems, and products for navigating UAVs in formation. 2. Description of Related Art Many form is of UAV are available in prior art, both domestically and internationally. Their payload weight carrying capability, their accommodations (volume, environment), their mission profiles (altitude, range, duration), and their command, control and data acquisition capabilities vary significantly. Routine civil access to these various UAV assets is in an embryonic state. Conventional UAVs are typically manually controlled by an operator who may view aspects of a UAV's flight using cameras installed on the UAV with images provided through downlink telemetry. Navigating such UAVs from a starting position to one or more waypoints requires an operator to have specific knowledge of the UAV's flight, including such aspects as starting location, the UAV's current location, waypoint locations, and so on. Operators of prior art UAVs usually are required generally to manually control the UAV from a starting position to a waypoint with little aid from automation. There is therefore an ongoing need for improvement in the area of UAV navigations. | <SOH> SUMMARY OF THE INVENTION <EOH>Exemplary methods, systems, and products are described for efficient, automated navigation of UAVs, including navigating UAVs in formation. That is, exemplary methods, systems, and products are described for navigating UAVs in formation, including assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern; identifying a waypoint for each UAV in dependence upon the UAV's pattern position; piloting the UAVs in the pattern toward their waypoints in dependence upon a navigation algorithm, where the navigation algorithm includes repeatedly comparing the UAV's intended position and the UAV's actual position and calculating a corrective flight vector when the distance between the UAV's actual and intended positions exceeds an error threshold. The actual position of the UAV may be taken from a GPS receiver on board the UAV. Assigning pattern positions to each of a multiplicity of UAVs flying together in a pattern may include designating an anchor position for the pattern and assigning pattern positions to the other UAVs relative to the anchor position, and identifying a waypoint for each UAV in dependence upon its pattern position may be carried out by designating a waypoint for the anchor position and calculating each UAV's waypoint in dependence upon the waypoint for the anchor and in dependence upon the UAV's position in the pattern. Each UAV's intended position may be specified by the UAV's position in the pattern, a cross track to the UAV's waypoint, and a flight schedule. Piloting the UAVs in dependence upon a navigation algorithm may include identifying a cross track to a waypoint for each UAV, the cross track having a cross track direction; piloting the UAV to a starting point on the cross track; calculating an airspeed for flying from the starting point to the waypoint on schedule; calculating a heading in dependence upon wind speed, wind direction, airspeed, and the cross track direction; and flying the UAV on the heading at the airspeed. Calculating a corrective flight vector may be carried out by selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint; calculating a corrective airspeed for arriving at the corrective waypoint on schedule; and calculating a corrective heading in dependence upon the calculated airspeed. Selecting a corrective waypoint on a cross track between a UAV's intended position and its waypoint may include selecting a corrective waypoint at a predetermined portion of the distance between a UAV's intended position and its waypoint. Calculating t corrective airspeed for arriving at the corrective waypoint on schedule may be carried out by calculating a groundspeed needed to bring the UAV to the remedial waypoint on schedule, including dividing the distance from the actual position to the corrective waypoint by the difference between the current time and the schedule time for the corrective waypoint. The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular descriptions of exemplary embodiments of the invention as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts of exemplary embodiments of the invention. | 20050124 | 20081223 | 20081002 | 87309.0 | G01C2100 | 2 | CAMBY, RICHARD M | NAVIGATING UAVS IN FORMATION | UNDISCOUNTED | 0 | ACCEPTED | G01C | 2,005 |
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11,041,939 | ACCEPTED | Arrangement for the step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle | An arrangement for step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle, particularly on a B-column or a C-column, includes a guide rail mounted on the body part, and a carriage which can be displaced along the guide rail, which can be fixed in defined adjusting positions, and which has a fastening device for the holding or deflecting fitting. The guide rail, which is arranged behind a column covering, is mountable on the vehicle body part by way of two mutually spaced fastenings. In the event of a vehicle collision, particularly a side impact, the forces acting upon a vehicle occupant's head are to be kept below a permissible limit value. Accordingly, it is provided that, in the event of a vehicle occupant's head impact onto the holding or deflecting fitting, starting from a defined force level, the guide rail and therefore the entire belt height adjusting arrangement, while absorbing energy, is laterally swivellable about an axis of rotation formed by one of two fastenings of the guide rails and extending in the transverse direction of the vehicle. | 1. An arrangement for step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle comprising: a guide rail mounted on the body part, a carriage which can be displaced along the guide rail, can be fixed in defined adjusting positions, and has a fastening device for the holding or deflecting fitting, and two mutually spaced fastenings by which the guide rail, which is arranged behind a column covering, is mountable on the body part, wherein, starting from a defined force level, the guide rail and therefore an entire belt height adjusting arrangement, while absorbing energy, is laterally swivellable about an axis of rotation formed by one of two fastenings of the guide rail and extending in the transverse direction of the vehicle upon impact of a vehicle occupant's head with the holding or deflecting fitting. 2. The arrangement according to claim 1, wherein, at its upper end, the guide rail is held in position on the body part by way of a screwed fastening, the screwed fastening forming the axis of rotation which is stationary during swivelling of the guide rail. 3. The arrangement according to claim 1, wherein, at its lower end, the guide rail interacts with the body part by way of at least one plug-type connection. 4. The arrangement according to claim 3, wherein the plug-type connection, at the body part, comprises a pair of spaced vertical longitudinal slots, through which respective hook-shaped holding tongues of the guide rail can be introduced, and wherein, viewed in the longitudinal direction of the vehicle, the longitudinal slots have a width which is significantly greater than a thickness of each holding tongue. 5. The arrangement according to claim 4, and further comprising a projecting, bent away lug provided at least on one upright longitudinal side of a longitudinal slot, the projecting, bent-away lug having a free end which interacts with an adjacent side wall of the holding tongue, the lug bending while absorbing energy during a swivelling movement of the guide rail about the axis of rotation. 6. The arrangement according to claim 5, wherein the lug is constructed on at least one of an internal reinforcing metal sheet and an internal metal sheet of the body part. 7. The arrangement according to claim 5, wherein, in an installed position of the guide rail, the lug extends at an angle with respect to the side wall of the holding tongue. 8. The arrangement according to claim 1, wherein said hollow body part is a B-column or a C-column. 9. The arrangement according to claim 6, wherein, in an installed position of the guide rail, the lug extends at an angle with respect to the side wall of the holding tongue. 10. An arrangement for adjustment of a fitting of a seat belt on a hollow body part of a motor vehicle comprising: a guide rail mounted on the body part by spaced fastenings, and a carriage which can be displaced along the guide rail and which can be fixed in defined adjusting positions, wherein the guide rail is laterally swivellable about an axis of rotation formed by one of the spaced fastenings and extending in the transverse direction of the vehicle upon impact of a vehicle occupant's head with the fitting. 11. The arrangement according to claim 10, wherein, at its upper end, the guide rail is held in position on the body part by said one of the spaced fastenings. 12. The arrangement according to claim 10, wherein, at its lower end, the guide rail interacts with the body part by way of at least one plug-type connection. 13. The arrangement according to claim 12, wherein the plug-type connection, at the body part, comprises a pair of spaced vertical longitudinal slots, through which respective hook-shaped holding tongues of the guide rail can be introduced, and wherein, viewed in the longitudinal direction of the vehicle, the longitudinal slots have a width which is significantly greater than a thickness of each holding tongue. 14. The arrangement according to claim 13, and further comprising a projecting, bent away lug provided at least on one upright longitudinal side of a longitudinal slot, the projecting, bent-away lug having a free end which interacts with an adjacent side wall of the holding tongue, the lug bending while absorbing energy during a swivelling movement of the guide rail about the axis of rotation. 15. The arrangement according to claim 14, wherein the lug is constructed on at least one of an internal reinforcing metal sheet and an internal metal sheet of the body part. 16. The arrangement according to claim 14, wherein, in an installed position of the guide rail, the lug extends at an angle with respect to the side wall of the holding tongue. 17. A motor vehicle including an arrangement for adjustment of a fitting of a seat belt on a hollow body part of the motor vehicle comprising: a guide rail mounted on the body part by spaced fastenings, and a carriage which can be displaced along the guide rail and which can be fixed in defined adjusting positions, wherein the guide rail is laterally swivellable about an axis of rotation formed by one of the spaced fastenings and extending in the transverse direction of the vehicle upon impact of a vehicle occupant's head with the fitting. 18. The motor vehicle according to claim 17, wherein, at its upper end, the guide rail is held in position on the body part by said one of the spaced fastenings. 19. The motor vehicle according to claim 17, wherein, at its lower end, the guide rail interacts with the body part by way of at least one plug-type connection. 20. The motor vehicle according to claim 19, wherein the plug-type connection, at the body part, comprises a pair of spaced vertical longitudinal slots, through which respective hook-shaped holding tongues of the guide rail can be introduced, and wherein, viewed in the longitudinal direction of the vehicle, the longitudinal slots have a width which is significantly greater than a thickness of each holding tongue. | This application claims the priority of German application 10 2004 003 966.6, filed Jan. 27, 2004, the disclosure of which is expressly incorporated by reference herein. BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates to an arrangement for the step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle, particularly on a B-column or C-column, having a guide rail mounted on the body part, and a carriage which can be displaced along the guide rail, can be fixed in defined adjusting positions and has a fastening device for the holding or deflecting fitting, and in which the guide rail, which is arranged behind a column covering, is mountable on the vehicle body part by means of two mutually spaced fastenings. Arrangements of the initially mentioned type, which are usually called belt height adjusting devices, are used for adapting the height of the deflecting or fastening point of a seat belt to the body size of a vehicle occupant to be protected. In four-door passenger cars, the belt height adjusting arrangements are normally mounted in the upper part of the B- and C-columns. For adjusting the height of a fitting, usually by pressure onto a cover cap of a screw connecting the holding or deflecting fitting with the carriage, a carriage is pressed against the force of a spring in the direction of the column, in order to release the fixing caused by mutual detent engagement of detent elements of the carriage and of a guiding rail, so that the carriage can be moved along the guide rail into the desired adjusting position. When the cover cap is subsequently relieved from pressure, the detent elements again enter into a mutual detent engagement, so that the carriage is held in the selected adjusting position. Many such arrangements are known from the prior art. Reference is made, for example, to German Patent Document DE 198 22 696 A1. There is a risk that a motor vehicle occupant's head will carry out a transverse motion and impact on an area in which the deflecting fitting is arranged when lateral forces act upon a vehicle equipped with the deflecting fitting in the event of an accident, for example. In this case, loads which are above a permissible limit value may act upon the vehicle occupant's head. It is known from German Patent Document DE 197 19 572 A1 to arrange a deformation element, which is designed for absorbing energy in the event of pressure admission to the seat belt linkage point, between the seat belt linkage point and the vehicle body part. Viewed in the transverse direction of the vehicle, such a deformation element requires a relatively large amount of additional space. It is known from German Patent Document DE 196 15 804 C2 to arrange a damping device between the adjusting part holding the deflecting fitting and the vehicle body part at which a rail is fastened or can be fastened. When impact-caused forces act upon the deflecting fitting, the damping device is supported on the adjusting part and the vehicle body part and can be deformable during the process for damping impact energy. A corresponding space has to be provided for housing such a damping device. It is an object of the invention to further develop a fastening for a belt height adjusting arrangement according to the above-mentioned type such that, in the event of a head impact onto the holding or deflecting fitting, loads acting upon the vehicle occupant's head are below the permissible limit value. According to the invention, this object is achieved by having the guide rail and therefore an entire belt height adjusting arrangement, while absorbing energy, be laterally swivellable, starting from a defined force level, about an axis of rotation, formed by one of two fastenings of the guide rail and extending in the transverse direction of the vehicle, upon impact of a vehicle occupant's head with the holding or deflecting fitting. Additional characteristics advantageously further developing the invention are defined by the dependent claims. Principal advantages achieved by the invention are that, in the event of a head impact onto the holding or deflecting fitting at a defined force level, the belt height adjusting arrangement, while absorbing energy, can be laterally swivelled about an axis of rotation formed by one of the two fastenings of the carrier rail and extending in the transverse direction of the vehicle. Energy is absorbed during swivelling of the belt height adjusting arrangement, and thus the head loads occurring are below the permissible limit value. Furthermore, an additional energy absorption can take place by deformation of the column covering disposed in front. In one embodiment, the belt height adjusting arrangement swivels about the upper fastening, and specifically, viewed from the vehicle occupant compartment, against the driving direction toward the rear. Thus, while absorbing energy, the belt height adjusting arrangement yields laterally in the longitudinal direction of the vehicle. Energy absorption is formed by a bent-away column-side lug which bends or deforms during the swivelling of the guide rail of the belt height adjusting device. As a result of the geometry of the lug (length, width, thickness, set angle), the force level can be defined, starting from which the lug bends during the swivelling of the guide rail. The invention will be explained in detail in the following by means of an embodiment illustrated in the drawing. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a belt height adjusting arrangement according to the invention mounted on a column; FIG. 2 is an enlarged sectional view of the column as seen along line II-II of FIG. 1; FIG. 3 is a perspective view of the door column with the guide rail in the installed position; FIG. 4 is a sectional view as seen along line IV-IV of FIG. 3; FIG. 5 is a view similar to FIG. 3 but with a swivelled guide rail after a head impact; FIG. 6 is a sectional view as seen along line VI-VI of FIG. 5; and FIG. 7 is a sectional view from the interior onto the door column, the position of the holding tongues being illustrated in both end positions. DETAILED DESCRIPTION OF THE INVENTION The belt height adjusting arrangement 1 for a seat belt 2 of a passenger car, which is illustrated in the drawing, essentially consists of a guide rail 5 mounted behind a column covering 3 on a column 4 of the passenger car; of a carriage 6 which can be displaced along the guide rail 5 and can be fixed in defined adjusting positions on the guide rail 5; of a slide 7 which is mounted in front of the guide rail 5 above a recess of the column covering 3 and has a passage opening 8; of a holding or deflecting fitting 9 with a guide slot 10 for the seat belt 2, as well as of a holding screw 12 for fastening the holding or deflecting fitting 9 on the carriage, which holding screw 12 penetrates the passage opening 8 of the slide 7 and is covered by a cover cap 11. As illustrated in FIG. 2, the section of the B- or C-column 4, which is used as a holding device for the guide rail 5 and, in the cross-section, is illustrated in a simplified trapezoidal manner, consists of a groove-shaped external metal sheet 13, of an internal metal sheet 14 profiled in a hat-shape, and of an internal reinforcing metal sheet 15 fastened to the internal metal sheet 14. The external metal sheet 13 and the internal metal sheet 14 are mutually connected on end-side flanges 16, 17 oriented in the same direction, by means of welding, gluing or the like. Sealing profiles, which are not shown in detail, are fitted onto the flanges 16, 17. In the illustrated embodiment, the column 4 forms the hollow vehicle body part. The profiled guide rail 5 of the belt height adjusting arrangement 1, which is arranged behind the column covering 3, can be mounted on the column 4 by way of two fastenings 18, 19 extending at a distance from one another viewed in the vertical direction. According to the invention, it is provided that, in the event of a vehicle occupant's head impact onto the holding or deflecting fitting 9, starting from a defined force level, the guide rail 5 and therefore the entire belt height adjusting arrangement 1, while absorbing energy, is laterally swivellable about an axis of rotation 20 formed by one of the two fastenings 18, 19 of the guide rail 5 and extending in the transverse direction of the vehicle. In the illustrated embodiment, the guide rail 5 is held in position on the column 4 at its upper end 21 by way of a screwed fastening forming the fastening 18, the screwed fastening forming the stationary axis of rotation 20 during the swivelling of the guide rail 5. On the area of the internal metal sheet 14 and of the reinforcing sheet 15 facing the vehicle occupant compartment 22, the screwed fastening has respectively aligned passage bores 23, in which case a screw nut 24 for a screw 25 used for the fastening of the guide rail 5 is welded onto a cavity-side surface of the reinforcing metal sheet 15 (FIG. 1). At its lower end 26, the guide rail interacts with the column 4 by way of at least one plug-type connection forming the fastening 19. On the column 4, the plug-type connection 19 comprises a pair of spaced vertical longitudinal slots 27 through which one hook-shaped holding tongue 28 respectively of the guide rail 5 can be introduced in order to support the guide rail 5 on the column 4 before it is fastened by means of the screw 25. Viewed in the longitudinal direction of the vehicle, the longitudinal slots 27 have a significantly greater width B1 than the thickness B2 of the holding tongue 28 (FIG. 7). A projecting bent-away lug 30 is constructed on at least one upright longitudinal side 29 of one of the two longitudinal slots 27 of the column 4, the free end of the lug 30 being supported on the adjoining side wall 31 of the holding tongue 28 of the guide rail 5. In this case, in the event of a head-impact-caused swivelling motion of the guide rail 5, the lug 30 bends or deforms while absorbing energy, that is, by work of deformation. In this embodiment, the trapezoidal, semicircular or similarly constructed lug 30 is arranged on an internal reinforcing metal sheet 15 of the column 4. However, it could also be provided on the internal metal sheet 14 of the column 4. In the installed position C of the guide rail 5, the lug 30 extends at an angle a of approximately 45° with respect to the adjoining side wall 31 of the holding tongue 28. In the embodiment, the angle a amounts to approximately 45°; however, it may also be smaller or larger than 45°. The lug 30 is oriented inward into the cavity of the column (FIGS. 2 and 4). When the guide rail 5 is swivelled into its end position D, the lug 30 is bent in the direction of the arrow R and extends approximately parallel to the side wall 31 of the holding tongue 28 (FIG. 6). In the driving operation, a vehicle occupant's head K extends at a distance from the holding or deflecting fitting 9 of the belt height adjusting arrangement 1 (FIG. 4). In the event of a vehicle collision, in particular, the vehicle occupant's head K may move toward the side in the direction of the belt height adjusting arrangement 1 and then come in contact with the column covering 3 or the holding or deflecting fitting 9 (FIG. 6). By means of the fastening of the guide rail 5 of the belt height adjusting arrangement 1 on the column 4 according to the invention, it is achieved that, in the event of the head impact, energy is absorbed first by the deformation of the column covering 3 and subsequently by the work of deformation during the swivelling of the guide rail 5, so that there is a reliable falling below the permissible limit values for the head impact. During the head impact, the guide rail 5 swivels about the upper axis of rotation 20, which extends in the transverse direction of the vehicle, in the longitudinal direction of the vehicle, specifically in the direction A against the driving direction F of the vehicle. The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. | <SOH> BACKGROUND AND SUMMARY OF THE INVENTION <EOH>The present invention relates to an arrangement for the step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle, particularly on a B-column or C-column, having a guide rail mounted on the body part, and a carriage which can be displaced along the guide rail, can be fixed in defined adjusting positions and has a fastening device for the holding or deflecting fitting, and in which the guide rail, which is arranged behind a column covering, is mountable on the vehicle body part by means of two mutually spaced fastenings. Arrangements of the initially mentioned type, which are usually called belt height adjusting devices, are used for adapting the height of the deflecting or fastening point of a seat belt to the body size of a vehicle occupant to be protected. In four-door passenger cars, the belt height adjusting arrangements are normally mounted in the upper part of the B- and C-columns. For adjusting the height of a fitting, usually by pressure onto a cover cap of a screw connecting the holding or deflecting fitting with the carriage, a carriage is pressed against the force of a spring in the direction of the column, in order to release the fixing caused by mutual detent engagement of detent elements of the carriage and of a guiding rail, so that the carriage can be moved along the guide rail into the desired adjusting position. When the cover cap is subsequently relieved from pressure, the detent elements again enter into a mutual detent engagement, so that the carriage is held in the selected adjusting position. Many such arrangements are known from the prior art. Reference is made, for example, to German Patent Document DE 198 22 696 A1. There is a risk that a motor vehicle occupant's head will carry out a transverse motion and impact on an area in which the deflecting fitting is arranged when lateral forces act upon a vehicle equipped with the deflecting fitting in the event of an accident, for example. In this case, loads which are above a permissible limit value may act upon the vehicle occupant's head. It is known from German Patent Document DE 197 19 572 A1 to arrange a deformation element, which is designed for absorbing energy in the event of pressure admission to the seat belt linkage point, between the seat belt linkage point and the vehicle body part. Viewed in the transverse direction of the vehicle, such a deformation element requires a relatively large amount of additional space. It is known from German Patent Document DE 196 15 804 C2 to arrange a damping device between the adjusting part holding the deflecting fitting and the vehicle body part at which a rail is fastened or can be fastened. When impact-caused forces act upon the deflecting fitting, the damping device is supported on the adjusting part and the vehicle body part and can be deformable during the process for damping impact energy. A corresponding space has to be provided for housing such a damping device. It is an object of the invention to further develop a fastening for a belt height adjusting arrangement according to the above-mentioned type such that, in the event of a head impact onto the holding or deflecting fitting, loads acting upon the vehicle occupant's head are below the permissible limit value. According to the invention, this object is achieved by having the guide rail and therefore an entire belt height adjusting arrangement, while absorbing energy, be laterally swivellable, starting from a defined force level, about an axis of rotation, formed by one of two fastenings of the guide rail and extending in the transverse direction of the vehicle, upon impact of a vehicle occupant's head with the holding or deflecting fitting. Additional characteristics advantageously further developing the invention are defined by the dependent claims. Principal advantages achieved by the invention are that, in the event of a head impact onto the holding or deflecting fitting at a defined force level, the belt height adjusting arrangement, while absorbing energy, can be laterally swivelled about an axis of rotation formed by one of the two fastenings of the carrier rail and extending in the transverse direction of the vehicle. Energy is absorbed during swivelling of the belt height adjusting arrangement, and thus the head loads occurring are below the permissible limit value. Furthermore, an additional energy absorption can take place by deformation of the column covering disposed in front. In one embodiment, the belt height adjusting arrangement swivels about the upper fastening, and specifically, viewed from the vehicle occupant compartment, against the driving direction toward the rear. Thus, while absorbing energy, the belt height adjusting arrangement yields laterally in the longitudinal direction of the vehicle. Energy absorption is formed by a bent-away column-side lug which bends or deforms during the swivelling of the guide rail of the belt height adjusting device. As a result of the geometry of the lug (length, width, thickness, set angle), the force level can be defined, starting from which the lug bends during the swivelling of the guide rail. The invention will be explained in detail in the following by means of an embodiment illustrated in the drawing. | <SOH> BACKGROUND AND SUMMARY OF THE INVENTION <EOH>The present invention relates to an arrangement for the step-by-step height adjustment of a holding or deflecting fitting of a seat belt on a hollow body part of a motor vehicle, particularly on a B-column or C-column, having a guide rail mounted on the body part, and a carriage which can be displaced along the guide rail, can be fixed in defined adjusting positions and has a fastening device for the holding or deflecting fitting, and in which the guide rail, which is arranged behind a column covering, is mountable on the vehicle body part by means of two mutually spaced fastenings. Arrangements of the initially mentioned type, which are usually called belt height adjusting devices, are used for adapting the height of the deflecting or fastening point of a seat belt to the body size of a vehicle occupant to be protected. In four-door passenger cars, the belt height adjusting arrangements are normally mounted in the upper part of the B- and C-columns. For adjusting the height of a fitting, usually by pressure onto a cover cap of a screw connecting the holding or deflecting fitting with the carriage, a carriage is pressed against the force of a spring in the direction of the column, in order to release the fixing caused by mutual detent engagement of detent elements of the carriage and of a guiding rail, so that the carriage can be moved along the guide rail into the desired adjusting position. When the cover cap is subsequently relieved from pressure, the detent elements again enter into a mutual detent engagement, so that the carriage is held in the selected adjusting position. Many such arrangements are known from the prior art. Reference is made, for example, to German Patent Document DE 198 22 696 A1. There is a risk that a motor vehicle occupant's head will carry out a transverse motion and impact on an area in which the deflecting fitting is arranged when lateral forces act upon a vehicle equipped with the deflecting fitting in the event of an accident, for example. In this case, loads which are above a permissible limit value may act upon the vehicle occupant's head. It is known from German Patent Document DE 197 19 572 A1 to arrange a deformation element, which is designed for absorbing energy in the event of pressure admission to the seat belt linkage point, between the seat belt linkage point and the vehicle body part. Viewed in the transverse direction of the vehicle, such a deformation element requires a relatively large amount of additional space. It is known from German Patent Document DE 196 15 804 C2 to arrange a damping device between the adjusting part holding the deflecting fitting and the vehicle body part at which a rail is fastened or can be fastened. When impact-caused forces act upon the deflecting fitting, the damping device is supported on the adjusting part and the vehicle body part and can be deformable during the process for damping impact energy. A corresponding space has to be provided for housing such a damping device. It is an object of the invention to further develop a fastening for a belt height adjusting arrangement according to the above-mentioned type such that, in the event of a head impact onto the holding or deflecting fitting, loads acting upon the vehicle occupant's head are below the permissible limit value. According to the invention, this object is achieved by having the guide rail and therefore an entire belt height adjusting arrangement, while absorbing energy, be laterally swivellable, starting from a defined force level, about an axis of rotation, formed by one of two fastenings of the guide rail and extending in the transverse direction of the vehicle, upon impact of a vehicle occupant's head with the holding or deflecting fitting. Additional characteristics advantageously further developing the invention are defined by the dependent claims. Principal advantages achieved by the invention are that, in the event of a head impact onto the holding or deflecting fitting at a defined force level, the belt height adjusting arrangement, while absorbing energy, can be laterally swivelled about an axis of rotation formed by one of the two fastenings of the carrier rail and extending in the transverse direction of the vehicle. Energy is absorbed during swivelling of the belt height adjusting arrangement, and thus the head loads occurring are below the permissible limit value. Furthermore, an additional energy absorption can take place by deformation of the column covering disposed in front. In one embodiment, the belt height adjusting arrangement swivels about the upper fastening, and specifically, viewed from the vehicle occupant compartment, against the driving direction toward the rear. Thus, while absorbing energy, the belt height adjusting arrangement yields laterally in the longitudinal direction of the vehicle. Energy absorption is formed by a bent-away column-side lug which bends or deforms during the swivelling of the guide rail of the belt height adjusting device. As a result of the geometry of the lug (length, width, thickness, set angle), the force level can be defined, starting from which the lug bends during the swivelling of the guide rail. The invention will be explained in detail in the following by means of an embodiment illustrated in the drawing. | 20050126 | 20080729 | 20050901 | 96764.0 | 0 | TO, TOAN C | ARRANGEMENT FOR THE STEP-BY-STEP HEIGHT ADJUSTMENT OF A HOLDING OR DEFLECTING FITTING OF A SEAT BELT ON A HOLLOW BODY PART OF A MOTOR VEHICLE | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,948 | ACCEPTED | Motor driven link press | The present invention provides a motor driven link press which enables working with a heavy press load and also enables a working cycle time to be improved even when a motor with a relatively low output power is used and which can be properly controlled easily. A motor driven link press comprises a link mechanism 1 that converts a rotating operation into a linear operation and a ram 6 that elevates and lowers for press working on the basis of this linear operation. The link mechanism 1 comprises a crank member 2 having a crank shaft 3 and an eccentric shaft portion 4, a pivoting link 5, a connecting rod 7, and a restraining link 8. The pivoting link 5 has a first to third connecting portions P1 to P3 and is connected to the eccentric shaft portion 4 of the crank member 2 using the connecting portion P1. The connecting rod 7 is connected to the second connecting portion P2 and the ram 6. The restraining link 8 is rotationally removably supported on a frame 9 and is connected to the connecting portion P3 to restrain pivoting of the pivoting link 5. A drive transmitting system 14 is provided to transmit driving effected by a motor 13 to the crank shaft 3 of the link mechanism 1. The drive transmitting system can control rotation of the motor 13 to transmit driving effected by the motor 13 so that an elevating and lowering operations of the ram 6 can be controlled. | 1-23. (canceled) 24. A link type punch press characterized by comprising a motor, a link mechanism that converts rotating operation transmitted by the motor via a drive transmitting system, into a linear operation, and a ram installed below said link mechanism to elevate and lower for press working on the basis of said linear operation, said link mechanism comprising a crank member having a crank shaft and an eccentric shaft portion, a pivoting link having a first to third connecting portions located at vertices of a triangle and which are used for rotatable connections, the first connecting portion being connected to the eccentric shaft portion of said crank member, a connecting rod having opposite ends connected to the second connecting portion and an upper end of said ram, respectively, and a restraining link having a proximal end rotationally movably connected to a frame and a leading end connected to the third connecting portion of said pivoting link, to regulate pivoting of said pivoting link, and in that the punch press comprises working type selecting means for selecting the type of quality of punching and motor rotating-direction control means for switching said motor between a forward direction and a backward directions depending on the type of working selected by the working type selecting means. 25. A link type punch press according to claim 24, characterized in that said drive transmitting system controls rotation of the motor to transmit rotational driving effected by said motor to said crank shaft so that an elevating and lowering operations of the ram can be controlled, and said motor is a servomotor. 26. A link type punch press according to claim 25, characterized in that motor rotation speed control means is provided to increase the rotation speed of the motor in order to further increase a lowering speed of the ram when said motor rotating-direction control means has set a motor rotating direction in which said ram moves at a higher speed during lowering than during elevation. | FIELD OF THE INVENTION The present invention relates to a motor driven link press applied to a punch press or another press machine. BACKGROUND OF THE INVENTION In mechanical punch presses, a crank mechanism is commonly used as a slide driving mechanism that converts a rotating operation of a motor into an elevating or lowering operation of a ram. Further, a flywheel is used, and a clutch is let in or released to rotate or stop the flywheel to drive or stop the ram. With the crank mechanism, curves for the elevating and lowering speeds of the ram are symmetric with respect to a bottom dead center. The lowering speed is thus the same as the elevating speed. However, for general press working including punch working, the ram preferably moves at lower speed during lowering in order to make the lowering operation silent or because of a requirement for a press load. However, the elevating operation is not particularly limited and is thus preferably faster. With a crank mechanism in which the lowering speed is the same as the elevating speed, it takes more time than required to achieve elevation. This increases a cycle time for punch working. Recently, apparatuses have been proposed which use a servomotor as a driving source to elevate and lower the ram via a crank mechanism without using any flywheels. The servomotor can freely change the speed of the ram during its stroke and can increase its lowering speed while reducing its elevating speed. However, the capabilities of the motor depend on its rotation speed. The motor must be operated within the range of the optimum motor rotation speed according to the characteristics of the motor. If the rotation speed of the motor is controlled so that the lowering speed differs from the elevating speed, it is impossible to make full use of capabilities of the motor. A large-sized motor is required to increase the elevating speed while obtaining a required press load. The applicant thus examined various slide mechanisms in order to select an appropriate slide mechanism that enables the ram to lower at a low speed while elevating at a high speed. A link press has long been used as a slide mechanism used for a press device for plastic forming such as cold extrusion or upsetting of metal (for example, the Examined Japanese Patent Application Publication (Tokkou-Hei No. 3-42159). The link press comprises a pivoting link connected to a crank pin of a crank mechanism and to which a connecting rod and a restraining link are connected. The crank shaft is driven by a motor via a flywheel. With this link press, the restraining link serves to characterize the operation of the ram so that the ram lowers at a low speed and elevates fast. However, the conventional link press is used to improve the quality of plastic forming such as cold extrusion by utilizing its very slow lowering operation performed near a bottom dead center. Thus, no conventional link presses have been applied to a punch press for which operational characteristics different from those for plastic forming are required. Further, the conventional link press is provided with a flywheel that stores output power from the motor as inertia energy. Consequently, it is difficult to properly control the conventional link press easily. It is thus an object of the present invention to provide a motor driven link press which enables working with a heavy press load and also enables a working cycle time to be improved even when a motor with a relatively low output power is used and which can be properly controlled easily. It is another object of the present invention to freely control an operation speed to accomplish various types of working while making use of advantages of the link press. It is yet another object of the present invention to ensure punching scraps are dropped when the link press is applied to a punch press. SUMMARY OF THE INVENTION A motor driven link press according to the present invention a motor, a link mechanism that converts rotating operation transmitted by the motor via a drive transmitting system, into a linear operation, and a ram installed below the link mechanism to elevate and lower for press working on the basis of this linear operation. The link mechanism comprises a crank member having a crank shaft and an eccentric shaft portion, a pivoting link having a first to third connecting portions located at vertices of a triangle and which are used for rotatable connections, the first connecting portion being connected to the eccentric shaft portion of the crank member, a connecting rod having opposite ends connected to the second connecting portion and an upper end of the ram, respectively, and a restraining link having a proximal end rotationally movably connected to a frame and a leading end connected to the third connecting portion of the pivoting link, the restraining link restraining pivoting of the pivoting link so that a lowering operation of the ram is slower than an elevating operation of the ram when the crank shaft is rotated at a fixed speed in one direction. The drive transmitting system controls rotation of the motor to transmit rotational driving effected by the motor to the crank shaft so that an elevating and lowering operations of the ram can be controlled. The drive transmitting system includes no parts such as a flywheel which are intended to apply inertia. The drive transmitting system may have a speed reducer or an output shaft of the motor and the crank shaft may be directly coupled together. The operation of this configuration will be described. The crank shaft is rotated to cause the pivoting link to perform a composite operation including a revolving operation along a turning locus of axis of the eccentric shaft portion and rotational motion in which the pivoting link pivots back and forth because the restraining link is connected to the pivoting link. The revolving operation of the pivoting link elevates or lowers the connecting rod connected to the pivoting link. However, the rotational motion hinders an elevating and lowering speed curve for the lower end position of the connecting rod, i.e. the ram position, from being quasi-sinusoidal. The curve for a lowering operation and the curve for an elevating operation are thus asymmetric. Which of the lowering and elevating operations is faster depends on a combination of various elements such as the support point position and length of the restraining link. Thus, these elements can be properly designed to allow the restraining link to regulate the pivoting of the pivoting link so that the lowering operation of the ram is slower than its elevating operation when the crank shaft is rotated at a fixed speed in one direction. By thus reducing the lowering speed, it is possible to accomplish working with a heavy press load and increase the lowering speed even when a motor with a relatively low output power is used. This improves a working cycle time. The above speed change can be accomplished with a fixed motor speed. Thus, for example, a speed reducer with an appropriate reduction ratio can be used to operate the motor with a motor rotation speed providing the maximum motor output power according to its characteristics. This also allows a motor with lower output power to be used. Further, the motor and the crank shaft are connected together via the drive transmitting system including no inertia applying systems such as a flywheel. Thus, for example, it is easy to provide such control as a change in ram speed based on, for example, the control of rotation speed of the motor. If the above motor is a servomotor, the motor speed can be freely changed. Accordingly, the speed of the ram can be changed during its elevating and lowering stroke. This enables working according to various requirements. That is, a speed curve based on operations of a link mechanism composed of the crank mechanism, pivoting link, restraining link, and the like is used as a basic speed curve observed if the motor is rotated at a uniform speed, and the motor speed is varied. Then, for example, the speed at which the punch tool contacts with a workpiece can be reduced to make operations more silent. Alternatively, the elevating speed can be further increased. The motor driven link press of the present invention may be a punch press. In this case, that section of elevating and lowering stroke of the ram which is used to punch a plate material workpiece is an intermediate section of lowering process of the elevating and lowering stroke. The section used for punching is determined by the relationship between the height of a table on which the plate material workpiece is placed and the ram position and the installation heights of a punch and a die tool, or the like. If the intermediate section of elevating and lowering stroke of the ram is thus used as a punching section, a sufficient stroke can be provided below the bottom surface of the plate material workpiece. This ensures that punching scraps are dropped. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded front view of a link mechanism in a motor driven link press according to an embodiment of the present invention. FIG. 2 is an exploded side view of this link mechanism. FIGS. 3A and 3B are a front view and a side view of this link mechanism, respectively. FIG. 4 is a side view showing this link mechanism and how it is connected. FIG. 5 is a perspective view showing a portion of the motor driven link press in which this link mechanism and a motor are installed on a main body frame. FIG. 6 is a partial perspective view of this link mechanism. FIG. 7 is a diagram illustrating an operation model of this link mechanism. FIG. 8 is a graph showing the relationship between a crank angle and the displacement of a ram in this link mechanism. FIG. 9 is a graph showing a comparison of this link mechanism with a crank type press in terms of process of the ram displacement. FIG. 10 is a plan view showing the whole motor driven link press of this embodiment. FIG. 11 is a side view showing the whole motor driven link press. FIG. 12 is an exploded side view showing a lower shift condition and a lower shift position of a ram shift mechanism in this motor driven link press. FIG. 13 is a plan view of a turret in this motor driven link press. FIGS. 14A and 14B are exploded side views showing the positional relationship between the ram and the turret and a punch tool, at an upper shift position and a lower shift position of this motor driven link press, respectively. FIG. 15 is an exploded front view of a link mechanism in a link press according to another embodiment of the present invention. FIG. 16 is a schematic view showing the positional relationship among connecting portions in a predetermined operating condition of this link mechanism. FIG. 17 is a graph showing the relationship between the crank angle and the ram displacement and the torque exerted on a crank shaft in the case in which the above positional relationship is established. FIG. 18 is a graph showing a locus of a third connecting portion in the case in which the above positional relationship is established. FIG. 19 is a graph showing a locus of a second connecting portion in the case in which the above positional relationship is established. FIG. 20 is a combination of an exploded front view of a link mechanism in a motor driven link press according to yet another embodiment of the present invention and a block diagram showing a conceptual configuration of a control system. FIGS. 21A and 21B are exploded front views each showing an operating condition of a link rotational-movement center changing means, respectively. FIG. 22 is a graph showing the relationship between the crank angle and the ram displacement and the torque in this link mechanism, at each rotational-movement center position of a restraining link. FIG. 23A is a diagram showing a conceptual configuration of a motor driven link press according to still another embodiment of the present invention, FIG. 23B is a diagram showing a crank operation of this link press, and FIG. 23C is a time chart for a plate material movement speed and a ram axis motor speed in this link press. FIGS. 24A and 24B are graphs showing the relationship between the crank angle and ram displacement in this link mechanism at the time when the motor is rotated in a forward and backward directions, respectively. FIG. 25 is a block diagram showing the relationship between a control device and its control program in this link press. FIG. 26 is a diagram showing an example of structure of a working program executed by this control device. FIG. 27 is a diagram illustrating specific examples of plate material moving means, ram axis control means, and parallel synchronization control means in this control device. FIG. 28 is a time chart of a plate material moving speed and a ram axis motor speed in this link press. FIG. 29 is a time chart showing the plate material moving speed and ram axis motor speed in this link press together with a comparative example. FIG. 30 is an exploded front view of a servomotor driven link press according to still another embodiment of the present invention. FIG. 31 is a graph showing the relationship between the crank angle and ram displacement in the case in which this link mechanism is stopped during lowering. FIGS. 32A to 32D are exploded front views showing tools that carry out various types of working using this servomotor driven link press, respectively. FIG. 33 is a combination of an exploded front view of a link mechanism in a motor driven link press according to further another embodiment of the present invention and a block diagram showing a conceptual configuration of a control system. FIGS. 34A and 34B are graphs showing the relationship between the crank angle and ram displacement in this link mechanism at the time when the motor is rotated in the forward and backward directions, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will de described with reference to the drawings. FIG. 1 is an exploded front view of a link mechanism in a motor driven link press. This motor driven link press comprises a motor 13, a link mechanism 1 that converts rotating operation transmitted by the motor 13 via a drive transmitting system 14, into a linear operation, and a ram 6 installed below the link mechanism 1 to elevate and lower for press working on the basis of the linear operation. The link mechanism 1 comprises a crank member 2 having an eccentric shaft portion 4 that is eccentric to the axis of a crank shaft 3, a pivoting link 5 connected to the eccentric shaft portion 4, a connecting rod 7, and a restraining link 8. The crank shaft 3 is rotatably installed on a frame 9 and receives rotational driving force. The eccentric shaft portion 4 has a larger diameter than the crank shaft 3. Instead of having a large diameter such as the illustrated one, the eccentric shaft 4 may have a smaller diameter than the crank shaft 3 and may be integrated with the crank shaft 3 via a crank arm (not shown in the drawings). The ram 6 is a member that elevates and lowers a press work applying section such as a punch tool. The ram 6 is installed on the frame 9 so as to freely elevate and lower via a guide member 10. The ram 6 is located immediately below the crank shaft 2. The pivoting link 5 has a first to third connecting portions P1 to P3 and is connected to the eccentric shaft portion 4 of the crank member 2 via the first connecting portion P1. The connecting portions P1 to P3 allow the pivoting link 5 to be rotatably connected and are located at the respective vertices of a triangle T as schematically shown in FIG. 7. The triangle T is arbitrarily formed in a plane perpendicular to the axis of the crank shaft 3. In FIG. 1, the connecting rod 7 has an upper end connected to the second connecting portion P2 of the pivoting link 5 and a lower end rotatably connected to the upper end of the ram 6 via a pin 11. The restraining link 8 has a proximal end rotationally movably supported on the frame 9 via a support point shaft 12 and a leading end connected to the third connecting portion P3 of the pivoting link 5. In the restraining link 8, a pivoting center, i.e. the axis of the support point shaft 12, and the third connecting portion P3 are arranged at respective sides of the crank shaft 3. These sides are located in the plane perpendicular to the axis of the crank shaft 3 and may be arranged laterally or longitudinally with respect to the entire motor driven link press. As shown in FIGS. 4 and 5, the crank shaft 3 is connected to an output shaft (not shown in the drawings) of the motor 13 via the drive transmitting system 14. The drive transmitting system 14 can control rotation of the motor 13 to transmit rotational driving effected by the motor 13 to the crank shaft 13 so that an elevating and lowering operations of the ram 6 can be controlled. Accordingly, the drive transmitting system 14 is means for transmitting the torque of the motor 13 without using any parts such as a flywheel which are intended to apply inertia. In this embodiment, the drive transmitting system 14 is composed of a speed reducer 15 and a coupling 16 that connects an output shaft of the speed reducer 15 to the crank shaft 3. The motor 13 is a servomotor. The speed reducer 15 and the motor 13 are, for example, integrated together to constitute a motor with a speed reducer. FIG. 2 is an exploded side view of the link mechanism 1. The crank shaft 3 extends from the opposite sides of the eccentric shaft portion 4 and is rotatably supported on the frame 9 via a bearing such as a journal bearing at the opposite sides. In the pivoting link 5, the inner diameter surface of a connecting hole constituting the first connecting portion P1 is fitted over the outer periphery of the eccentric shaft portion 4 via a liner 18. The second connecting portion P2 of the pivoting link 5 and the connecting rod 7 are connected together by a connecting pin 19. The connecting rod 7 has a ram shift mechanism 20 at an intermediate position in its length direction to change its length between two levels to switch the lower end position of the ram 6 between an upper shift position and a lower shift position. The ram shift mechanism 20 has a shift driving source 21 composed of a cylinder device or the like and driven to switch the shift position. As described in detail later, the switching of the shift position is used to allow a punch tool to be replaced with a different one while keeping the top dead center of the punch tool lower than a standby punch tool on a turret, the top dead center being associated with driving with the ram 6. The top dead center of the punch tool is kept lower in order to improve the cycle time and allow the use of a crank member 2 with a small eccentricity to reduce the torque of the motor. Both link mechanism 1 and ram shift mechanism 20 serve to reduce the torque. The distance between the lower shift position and the bottom dead center, i.e. an elevating and lowering stroke of the punch tool and the ram 6, is about the triple of eccentricity of the eccentric shaft portion 4 of the crank member 2. As shown in FIG. 5, the frame 9 is an independent link portion frame that supports the link mechanism 1. It is attached to the leading end of upper frame portion 22a of a main body frame 22. The link portion frame 9 is shaped like a box. The frame 9 supports the opposite ends of the crank shaft 3 using a support plate 9b provided on the inner surface of an attaching substrate 9a and an opposite 9c opposite to the support plate 9b. A motor supporting member 23 is provided on the frame 9. The motor 13 is installed on the motor supporting member 23. Accordingly, the motor 9 is removably assembled to the main body frame 22 together with the link portion frame 9 on which the link mechanism 1 is installed. The main body frame 22 has a C-shaped side having an opening portion 24 into which a plate material workpiece or a tool support is advanced. The main body frame 22 has a pair of opposite side plates. FIG. 5 shows only one of the opposite side plates. In the upper frame portion 22a, the opposite side plates are joined together using an upper-frame bottom surface plate 25 and an intermediate reinforcing plate 26. FIGS. 10 and 11 are a general plan view and side view showing an example in which the motor driven link press provided with the link mechanism 1 in FIG. 1 is applied to a punch press. The main body frame 22 is covered with a frame cover 30. In addition to the link mechanism 1, tool supporting means 28 and work feeding means 29 are installed in the main body frame 22. A plurality of punch tools 31 and die tools 32 are mounted on the tool supporting means 28 so that any one of the tools 31, 32 can be indexed to a position Q at which the ram 6 carries out press working (FIG. 11). The tool supporting means 28 is composed of an upper turret 28a and a lower turret 28b on which the punch tools 31 and the die tools 32, respectively, are mounted. The work feeding means 29 moves a plate material workpiece W on a table 33 in the directions of two orthogonal axes (X-axis and-Y axis) so that an arbitrary portion of the workpiece W is located at the press working position Q. The work feeding means 29 has a carriage 34 moving in a longitudinal direction (the direction of the Y axis) and a cross slide 35 mounted on the carriage 34 so as to move in a lateral direction (the direction of the X axis). A plurality of work holders 36 provided on the cross slide 35 grasp the plate material workpiece W. The plate material workpiece W is fed in the direction of the two axes by the longitudinal movement of the carriage 34 and the lateral movement of the cross slide 35. The operation of the above configuration will be described. A description will be described later of the specific configuration and operation of the ram shift mechanism 20. The link mechanism 1 in FIG. 1 performs the operation described below as can be seen in the schematic diagram in FIG. 7. When the crank shaft 3 is driven and rotated by the motor, the center of eccentric shaft portion 4 of the crank member 2 draws a circumferential locus C1 around the axis of the crank shaft 3 as shown in FIG. 7. The pivoting link 5 is rotatably connected to the eccentric shaft portion 4 via the first connecting portion P1 and thus makes revolutionary motion along the circumferential locus C1. The pivoting link 5 is connected to the restraining link 8 via the third connecting portion P3 and thus has its operation regulated. Concurrently with the revolutionary motion, the pivoting link 5 makes rotational motion by pivoting back and forth around the first connecting point P1. The composite operation including this revolutionary motion and rotational motion causes the second connecting portion P2 to move along an oblique elliptical locus C2 as shown in this figure, the connecting portion P2 being provided in the pivoting link 5 to connect to the connecting rod 7. The ram 6 is supported so as to only elevate and lower freely and is connected to the second connecting portion P2 of the pivoting link 5 via the connecting rod 7. Accordingly, the ram 6 elevates and lowers when the second connecting portion P2 draws an elliptical locus. The speeds of elevating and lowering operations of the ram 6 are asymmetric as shown in FIG. 8 by a curve H indicating the relationship between crank angle and displacement during one period. Further, a crank angle θ BDC at which the ram 6 reaches a bottom dead center BDC is different from 180 degrees. A curve J, also shown in FIG. 8, indicates the vertical displacement of a ram in a general crank mechanism. It also indicates that the lowering and elevating speeds are symmetric. The operation of the link mechanism 1 is affected by the following eight elements shown in FIG. 7: the crank length (eccentricity) r, the length w of the restraining link 8, the length L of the connecting rod 7, the opening angle α between the connecting portions P2, P3 of the pivoting link 5, the lengths a, b between the connecting portion P1 and both connecting portions P2, P3 of the pivoting link 5, and Ex on the coordinate X and Ey on the coordinate Y of the support point position of the restraining link 8. The center of the coordinates is the axis of the crank shaft 3. To establish the link mechanism 1, a four-node rotation chain must be established in which the rotational center of the crank shaft 3, the connecting portion P1, the connecting portion P3, and the support shaft 12 of the restraining link 8 are established as the connecting points between the nodes. Further, when the shortest node is defined as the crank length r, the expressions shown below must be met. When A={square root}{square root over ( )}(Ex{circumflex over ( )}2+Ey{circumflex over ( )}2) r+a≦w+A r+w≦a+A r+A≦a+w This is known as the Grashof formula. The displacement curve of the ram 8 can be freely designed by properly setting values for the above elements so as to meet these conditions. Which of the lowering and elevating operations is faster is determined by the rotating direction of the motor and the combination of the above elements. Thus, when the motor is rotated in a fixed direction, the proper design of the elements enables an operation in which the lowering speed of the ram 6 is lower than its elevating speed when the motor 13 is rotated at a fixed speed. In this manner, a decrease in lowering speed enables working with a heavy press load and increases the elevating speed, even with the use of a relatively low output power. This improves a working cycle time. FIG. 9 shows a comparison of a crank type press with a link type press. If the cycle time is expressed as “10”, both lowering and elevating times of the crank type are “5” as shown in FIG. 9A. However, the link type can be designed so that the lowering time is “7” and the elevating time is “3” as shown in FIG. 9B. If the link mechanism 1 is designed in this manner, then the ram speed during a lowering operation is lower than that accomplished with the crank type; the crank type press is five-sevenths of the link type press. The press load is correspondingly heavier than that can be accomplished with the crank type; the crank type press is seven-fifths of the link type press. This amounts to a 40% improvement in press load. When the ram 7 elevates, work is not particularly carried out. Consequently, working is not affected by the weaker force. Further, the above speed change is made with the motor speed fixed. Accordingly, the use of a speed reducer 15 (FIG. 4) with an appropriate reduction ratio enables the motor to operate at a motor rotation speed at which it provides the maximum output power according to its characteristics. This also allows the use of the motor 13 with low output power. Further, the motor 13 and the crank shaft 3 are connected together via the drive transmitting system 14 that does not include any inertia applying systems such as a flywheel. Therefore, control can be properly provided easily, e.g. the ram speed can be changed by controlling the rotation speed of the motor. If the motor 13 is a servomotor, the motor speed can be freely changed. Accordingly, the speed of the ram 6 can also be changed during its elevating and lowering stroke. This enables working according to various requirements. That is, a speed curve based on operations of the link mechanism 1 composed of the crank member 2, pivoting link 5, restraining link 8 and the like is used as a basic speed curve observed if the motor 13 is rotated at a uniform speed, and the motor speed is varied. Then, for example, the speed at which the punch tool 31 contacts with the plate material workpiece W can be reduced to make operations more silent. Alternatively, the elevating speed can be further increased. Further, the ram 6 can be stopped at an arbitrary height. If this motor driven link press is used to carry out press working, a punch section M used to punch the plate material workpiece W must be an intermediate section of lowering process of a ram elevating and lowering stroke. In the intermediate section used as the punching section M, a curve H for displacement with respect to the crank angle of the ram 6 is substantially linear. A lower limit position H1 of the punching section M is located slightly above a die height DH. With the link press, when the motor speed is fixed, the curve is gentle near the top dead center TDC, linear during the intermediate section, and gentle again near the bottom dead center BDC. The speed is lowest near the bottom dead center BDC so that the heaviest press load is obtained near the bottom dead center BDC. With a conventional link press for forming, a heavy press load near the bottom dead center BDC is used for forming. However, with punch working, a stroke must be provided below the bottom surface of the plate material workpiece W to ensure that punching scraps are dropped. In contrast, if the intermediate section of the stroke is the punching section M, a sufficient stroke can be provided below the bottom surface of the plate material workpiece W to ensure that punching scraps are dropped. Thus, an inherently light press load in the intermediate section can be compensated for by the link mechanism 1. In other words, the neighborhood of the bottom dead center BDC, in which a heavy press load is obtained, can thus not be used but the link mechanism 1 can be used more efficiently than the conventional crank mechanism with symmetrical operations. Press working requires not only a heavy press load but also an increased working speed. Further, for punch working, a higher punching speed improves working quality. Further, the use of the intermediate section as the punching section M efficiently provides the punching speed required to achieve the desired working quality. In this manner, if this embodiment is applied to a punch press., the operation of the link mechanism 1 can be effectively used in a manner different from the one in which the conventional link press for forming is used. Now, with reference to FIGS. 13 and 14, a description will be given of the height relationship between each shift position of the ram shift mechanism 20 and the punch tools 31 on the tool supporting means 28. The punch tools 31 (311 to 318) supported at the respective positions on the upper turret 28a of the tool supporting means 28 are held at a given height except the punch tool 311 at a press working position Q. The punch tools are held at the given height by, for example, engaging necks of the punch tools 31 with respective position-fixing guide rings (not shown in the drawings) provided on the turret 28a along its circumferential direction or providing the turret 28a with supporting spring members (not shown in the drawings) for the respective punch tools 31. The guide rings are each shaped to have a lacking portion at the press working section Q. The height of each punch tool 31 supported on the turret 28a as described above corresponds to, for example, the position at which the bottom surface of the punch tool 31 is located substantially at the bottom surface of the turret 28a. In this embodiment, the ram 6 is adapted to engage with the neck of the punch tool 31 carried to the press working position Q to forcibly pull this tool 31 up. The punch tools 31 at the other positions are supported by the guide rings. The neck is engaged with the ram 6 by fitting a T-shaped head of the punch tool 31 into a groove formed in the lower end of the ram 6 and having a T-shaped cross section and suspending the neck of the punch tool 31, corresponding to a constricted portion of the T-shaped head. To use the ram 6 to drive elevating or lowering of the punch tool 31 at the press working position Q, the punch tool 31 at the top dead center position of elevating and lowering stroke of the ram 6 is positioned below the other punch tools 31 on the turret 28a as shown in FIG. 14B. If the top dead center position of the punch tool 31 at the press working position Q is thus lowered and the height of the ram 6 remains unchanged, when the turret 28a is rotated, the other punch tools 31 may interfere with the side of the ram 6 to hinder the tool from being changed for the ram 6. This is because the lower end of the ram 6 extends below the upper end of each of the other punch tools 31 on the turret 28a. Thus, the ram shift mechanism 20 is used to switch the lower end position of the ram 6 between the upper shift position and the lower shift position. In this case, after the ram 6 has been set at the top dead center position using the link mechanism 1 and at the upper shift portion using the ram shift mechanism 20, the punch tool 31 supported by the ram 6 is placed at the same height as the other punch tools 31 on the turret 28a as shown in FIG. 14A. Then, the tool can be smoothly changed for the ram 6 simply by rotating the turret 28a. Punch working is carried out by using the ram shift mechanism 20 to set the ram 6 at the lower shift position as described above. This enables the top dead center of elevating and lowering stroke of the punch tool 31 to be lowered to minimize the distance between the punch tool 31 and the surface of the plate material workpiece W. This allows the ram stroke to be designed to be shorter. It is thus possible to reduce the time elapsed after the punch tool 31 has left the top dead center and before it comes into contact with the surface of the plate material workpiece W or the time required for the punch tool 31 to elevate and retreat. Therefore, the cycle time for working can be improved. While the top dead center of the punch tool 31 is lowered to improve the cycle time, the tool can be easily changed for the ram 6. The ram shift mechanism 20 will be described in detail with reference to FIGS. 1 and 12. In the ram shift mechanism 20, the connecting rod 7 is divided into an upper rod 7a and a lower rod 7b that are coupled together so as to expand and contract freely. A slider 52 (FIG. 12) is releasably interposed between the ends of the upper and lower rods 7a, 7b. A releasing position of the slider 52 determines the thickness of that portion of the slider 52 which is present between the upper and lower rods 7a, 7b. Further, the ram shift mechanism 20 is provided with an interlocking mechanism 53. The interlocking mechanism 53 operates mechanically in union with the insertion or removal of the slider 52 to elevate or lower the lower rod 7b so as to allow the upper and lower rods 7a, 7b to contact with each other via the slider 52 without any gaps even when the slider 52 is inserted or removed. In the divided portion of the connecting rod 7, the upper part of the lower rod 7b is removably coupled to the lower part of the upper rod 7a. Specifically, the bottom of the upper rod 7a is formed to be hollow so that the upper part of the lower rod 7b is fitted into this hollow hole so as to be slidable in a longitudinal direction of the rod 7. The interlocking mechanism 53 is a cam mechanism composed of guide plates 54 each having a guide slot 55 and active rods 56 that engage slidably with the respective guide slots 55 in the guide plate 54. The two guide plates 54 are provided on the respective sides of the slider 52 and fixed to the slider 52 at their front and rear ends. The guide plate 54 has the guide hole 55 formed in its portion protruding below the slider 52. The pair of active rods 56 is provided at the upper end of the lower rod 7a so as to protrude in a direction orthogonal to the longitudinal direction of the rod 7a. The active rods 56 engage with the respective guide slots 55, located on the corresponding sides of guide plate 54. A slot 57 out of which the active rods 56 of the lower rod 7b are protruded is formed in the lower part of the upper rod 7a, which is formed into a hollow shaft, along its longitudinal direction. The guide slots 55 in the respective guide plates 54 are shaped so that their front half extends in a substantially horizontal direction, while their rear half is inclined upward. When the guide plates 54 are advanced together with the slider 52 as shown in FIG. 12B, the lower rod 47b is lifted while being guided by the guide slots 55. This reduces the external length of the connecting rod 7. The slider 52 is releasably inserted into a horizontal hole 64 formed in the upper rod 7a, and is advanced and retreated by a shift driving source 21 attached to the upper rod 7a and composed of an air cylinder or the like. Specifically, the horizontal hole 64 is formed along the upper bottom surface of hollow shaft portion of the upper rod 47a. Further, a fitting concave 52a into which an upper end 7bb of the lower rod 7b is fitted is formed in the bottom surface of the slider 52, which is opposite the upper end 7bb of the lower rod 7b. The upper end 7bb of the lower rod 7b can be fitted into the fitting concave 52a after the slider 52 has moved to a predetermined releasing position with respect to the upper rod 7a. Since the fitting concave 52a is formed, the thickness of the slider 52 varies depending on its releasing position. That is, a portion of the slider 52 in which the fitting concave 52a is formed is thinner. On the other hand, a portion of the slider 52 in which the fitting concave 52a is not formed is thicker. The upper end 7bb of the lower rod 7b is formed as a boss protruding from the upper end surface of the lower rod 7b. The ram shift mechanism 20 is set at the lower shift position in order to carry out press working. In FIG. 1, ram axis control means 61 for controlling the motor 13 used to drive the crank shaft 3 permits the motor 13 to drive the crank shaft 3 after the ram shift mechanism 20 has set the ram 6 at the lower shift position. The ram shift mechanism 20 has shift position detecting means 62 for detecting the lower shift position. The shift position detecting means 62 may be provided in the shift driving source 21. The ram axis control means 61 controls the motor 13 according ram driving commands provided by a working program (not shown in the drawings) or the like. The ram axis control means 61 is provided, for example, as a part of a numerical control device (not shown in the drawings) that controls the entire motor driven link press. Operations of the ram shift mechanism 20 will be described. To set the ram 6 at the upper shift position, the external length of the connecting rod 7 is reduced as described below. That is, the shift driving source 21 effects driving such that the slider 52 advances from the regular position shown in FIG. 12A to a predetermined position as shown in FIG. 12B. Thus, the fitting concave 52a in the slider 52 reaches a position at which it extends through the interior of the upper rod 7a. Further, the active rods 56 of the lower rod 47b are guided through the guide slots 55 in the guide plates 54, which advance integrally with the slider 52. The lower rod 7b advances into the fitting concave 52a in the slider 52 so that its upper end 7bb comes into contact with the upper bottom surface of the fitting concave 52a. The external length of the sliding rod 7 is thus reduced. When the shift driving source 21 effects such driving as returns the slider 52 to the position in FIG. 12A, the connecting rod 7 returns to its original length. The ram shift mechanism 29 configured as described above thus expands and contracts the connecting rod 7. Consequently, compared to vertical shifting of the entire link mechanism 1 including the crank shaft 3 and the links 5, 8, it is unnecessary to have a large-scale mechanism or use a large-sized driving source for shifting. Further, the ram shift mechanism 20 has only to have a simple configuration. Furthermore, the connecting rod 7 is expanded and contracted by the operation of the interlocking mechanism 53, composed of the guide slots 55 and active rods 56, as the slider 42 is advanced and retreated. Consequently, no separate driving sources for expansion and contraction need be provided, thus further simplifying the configuration. This reduces costs. Further, the connecting rod 7 can be expanded or contracted before the slider 52 is completely moved. This reduces the operation time required for expansion and contraction. If an attempt is made to use the motor 13 to drive the ram 6 with the ram shift mechanism 20 placed at the upper shift position, then the function of the ram axis control means 61 hinders the driving to prevent errors. In the above described embodiment, the ram shift mechanism 20 expands and contracts the connecting rod 7. However, the ram shift mechanism 20 has only to be able to switch the lower end position of the ram 6 between the upper shift position and the lower shift position. For example, the ram shift mechanism 20 may shift the entire link mechanism 1 in a vertical direction. Further, in the above described embodiment, a servomotor is used as the motor 13. The servomotor need not necessarily be used. Furthermore, in the above description, the embodiment is applied to a punch press. However, the motor driven link press of the present invention is applicable not only to punch working but also to various other types of press working such as forming and bending. Another embodiment will be described below with reference to the drawings. As shown in FIGS. 15 and 16, a pivoting center E of the restraining link 8, i.e. the axis of its support point shaft 12, and its third connecting portion P3 are arranged at the respective sides of the crank shaft 3. Further, the restraining link 8 is arranged so that when the eccentric shaft portion 4 of the crank member 2 is at the top dead center, a part 4a (shaded part) of the eccentric shaft portion 4 is located above a straight line A joining the pivoting center E of the pivoting link 8 with the connecting portion P3. In other words, the restraining link 8 is arranged so that when the eccentric shaft portion 4 is at the top dead center, the straight line A passes through the cross section of the eccentric shaft portion 4. FIG. 16 is a schematic view indicative of position of each portion when the eccentric shaft portion 4 is at the top dead center. The restraining link 8 is shaped to have a bent portion 8a bent upward as shown in FIG. 15 to avoid interference with the pivoting link 5. In this embodiment, the bent portion 8a covers substantially the total length of the restraining link 8, so that the restraining link 8 is substantially entirely bent like an arc of a general semicircle. The bent portion 8a may be formed only in part of the restraining link 8 in its length direction. In this link press, the pivoting center E and third connecting point P3 of the restraining link 8 are arranged at the respective sides of the crank shaft 3. Further, the restraining link 8 is arranged so that when the eccentric shaft portion 4 of the crank member 2 is at the top dead center, the part 4a of the eccentric shaft portion 4 is located above the virtual straight line A (FIG. 16) joining the pivoting center E of the pivoting link 8 with the connecting portion P3. It has been confirmed that this arrangement relationship results in the operational characteristics indicated in FIG. 17. In this figure, the axis of abscissa indicates the crank angle during one period, whereas the axis of ordinate indicates the displacement of the ram and the torque exerted on the crank shaft when a predetermined load is applied to the ram. The crank shaft torque is proportional to the motor torque if the drive transmitting system 14 does not include any elements such as flywheel which are intended to apply inertia as in the case with this embodiment. A curve H indicates the ram displacement, and a curve TH indicates a variation in torque. In this case, it has been confirmed that the third connecting point P, constituting the leading end of the restraining link 8, reciprocates on a locus C3 of an arc curve as shown in FIG. 18 and that the second connecting point P2 draws a locus C2 of an elliptic curve as shown in FIG. 19. As can be seen in FIG. 17, the parts of the ram displacement curve H corresponding to elevation and lowering, respectively, are asymmetric, and the crank angle θ BDC set when the ram 6 reaches the bottom dead center BDC is not 180 degrees as shown in FIG. 8 and described previously. For a lowering operation, the ram displacement curve H exhibits linearity in a long section AH extending from the neighborhood of the top dead center TDC to the neighborhood of the bottom dead center BDC. The lowering speed of the ram 6 remains substantially fixed within the section AH. Further, the torque remains almost fixed in a long section AT of the section AH which is longer than half of the section AH. The section AT with the substantially fixed torque can be effectively used for punch working as described later. Further, the ram displacement curve H is not angular but relatively gentle on sections ATT located near the top dead center TDC, specifically at the respective sides of the top dead center TDC. This indicates that the ram 6 is not significantly accelerated, i.e. the ram 6 does not markedly change its speed, when turning around at the top dead center TDC. Therefore, when the ram 6 changes its operating direction at the top dead center TDC, only a small impact is applied to the machine. This is advantageous in the design of strength of the machine and its durability. In this manner, if this embodiment is applied to a punch press, the operation of the link mechanism 1 can be effectively used in a manner different from the one in which the conventional link press for forming is used. In particular, the operational characteristics shown in FIG. 17 are effective on punch working, the operational characteristics resulting from the restraining link 8 arranged so that the part 4a of the eccentric shaft portion 4 is located above the straight line A joining the pivoting center E of the pivoting link 8 with the connecting portion P3 as described above. As shown in this figure, in the intermediate section used as the range in which the ram 6 carries out working, the lowering speed of the ram 6 remains fixed. Further, the corresponding crank shaft torque remains constant. This serves to enable stable punch working. Moreover, in the link mechanism 1, the pivoting center E and third connecting point P3 of the restraining link 8 are arranged at the respective sides of the crank shaft 3 as shown in FIG. 15. Consequently, this configuration is compact in the vertical and lateral directions. The restraining link 8 is shaped to have the bent portion 8a bent upward to avoid interference with the pivoting link 5. As a result, the compact link mechanism 1 with the above arrangement can be implemented without any interference with the pivoting link 5. Yet another embodiment of the present invention will be described below with reference to the drawings. FIG. 20 is a combination of a view of a link mechanism in this motor driven link press and a block diagram showing a conceptual configuration of a control system. As shown in FIG. 20, the frame 9 is provided with a link rotational-movement center changing means 510 for changing the position of the rotational-movement center E at the proximal end of the restraining link 8. As shown in FIGS. 20 and 21, the link rotational-movement center changing means 510 is composed of rotational moving members 520 on which the support point shaft 12 is provided as an eccentric portion and an actuator 530 that rotationally moves the rotational moving members 520. Each of the rotational moving members 520 has a shaft portion 520a (FIG. 21) which coincides with its central portion. Using the shaft portion 520a, the rotational moving member 520 is rotatably supported on the frame 9 via a bearing (not shown in the drawings). The restraining link 8 has its proximal end rotationally movably supported on the support point shaft 12. The rotational moving members 520 are rotationally moved to change the position of the support point shaft 12 and thus the rotational-movement center E of the restraining link 8. The pair of rotational moving members 520 are coaxially provided, with the support point shaft 12 extending across both rotational moving member 520. The actuator 530 is a fluid pressure cylinder such as an air cylinder, or a motor, or an electromagnetic solenoid. Lock means 540 is provided to fix the rotational-movement center E of the restraining link 8 at each position set by the link rotational-movement center changing means 510. The lock means 540 is composed of engaged portions 550 formed in the rotational moving member 520, a lock member 560 that engages with the engaged portion 550, and a disengagement driving source 570 that engages and disengages the lock means 560. The engaged portions 550 are each composed of a concave formed in the outer peripheral surface of the rotational moving member 520. The lock member 560 is composed of a pin-like member that can be freely advanced and retreated. The disengagement driving source 570 is composed of a fluid pressure cylinder or an electromagnetic solenoid and is installed on the frame 9. The two engaged portions 550 of the rotational moving member 520 are formed at the respective circumferentially separate positions. The lock member 560 can be engaged with the opposite engaged portion 550 by rotationally moving the rotational moving member 520. Accordingly, the rotational-movement center E of the restraining link 8 can be fixed at the two positions. Three or more engaged portions 550 may be formed so that the rotational-movement center E can be fixed at three or more positions. This embodiment is characterized in that the link rotational-movement center changing means 51 in FIG. 20 changes the position of the rotational-movement center E to change the displacement curve for the ram 6 as described below. Description will be given of changes in link characteristics observed when the rotational-movement center E of the restraining link 8 is changed. With the positional and dimensional relationships established among the components of the link mechanism 1 shown in FIG. 20, the results of analysis indicate a ram displacement curve HA, shown in FIG. 22, is obtained if the rotational-movement center E is positioned in the upper part of the rotational moving member 520 as shown in FIG. 21A. This is the same as the ram displacement curve H shown in FIG. 8. For the convenience of comparison, FIG. 22 shows that, in the ram displacement curve HA, the crank angle corresponding to the bottom dead center is 180 degrees. The torque associated with the ram displacement curve HA results in a long lowering section in which the torque remains unchanged, as shown by a curve TA in FIG. 22. In contrast, when the rotational-movement center E is moved downward and leftward relative to its original position as shown in FIG. 21B, a ram displacement curve HB, shown in FIG. 22, is obtained. This curve indicates that the lowering speed of the ram is higher than that indicated by the curve HA obtained before the change. The torque associated with the ram displacement curve HB varies markedly as the ram lowers as shown by a curve TB in FIG. 22. The link rotational-movement changing means 510 changes the rotational-movement center E to enable the free selection of one of the two ram displacement curves HA, HB. The ram displacement curve HA, corresponding to a lower lowering speed, advantageously allows working to be accomplished using a motor 13 with low output power if working with a heavy load is carried out, e.g. if the plate material workpiece W has a large board thickness, if it is composed of a hard material, or if a punch tool with a large outer diameter is used for working. The ram displacement curve HB, corresponding to a higher lowering speed, advantageously enables high-speed punching and thus high-quality working with few burrs if working is possible with a light load, e.g. if the plate material workpiece W has a small board thickness. In this manner, the link rotational-movement center changing means 510 can be used to change the characteristics of the link mechanism 1 in order to select the optimum characteristics according to the type of working. Link characteristic control means 670 (FIG. 20) is preferably provided depending on the type of working, to control the link rotational-movement center changing means 510. Link characteristic control means 670 is provided, for example, in working control means 610. The link characteristic control means 670 determines the type of working on the basis of predetermined working type identification information. The working type identification information may be, for example, predetermined commands or information in a working program 650, predetermined commands or information provided by higher control means (not shown in the drawings) for the working control means 610, or predetermined commands or information inputted from an operation panel (not shown in the drawings) by an operator. The link characteristic control means 670 has, for example, a correspondence table (not shown in the drawings) that shows the correspondences between the predetermined working type identification information and the position of the rotational-movement center E, controlled by the link rotational-movement center changing means 510. The link characteristic control means 670 controls the position of the rotational-movement center E by checking the working type identification information against the correspondence table. The working type identification information may be a combination of plural pieces of information, e.g. a combination of the board thickness, a working circumferential length, and the like. The control system will be described. The working control means 610 is a device that controls the whole motor driven link press. It is composed of a computerized numerical control device and a programmable controller both controlled by the working program 650. The working control means 610 is provided with a control function of confirming, if the rotational-movement center E of the restraining link 8 has been changed, that the changed position has been fixed and then starting to drive the motor 13. This and other functions will be described. The working control means 610 has link characteristic control means 670, change commanding means 620, change corresponding motor angle control means 630, and lock confirming and working permitting means 640. The change commanding means 620 may be a part or the whole of the link characteristic control means 670. In response to a predetermined command from the working program 650, the change commanding means 620 recognizes the type of working to control the link rotational-movement center changing means 510 to change the rotational-movement center E of the restraining link 8 according to the type of working. The change commanding means 620 classifies working into two types including heavy load working and light load working. For the heavy load working, the rotational-movement center E is set at a position corresponding to a heavy load (the position shown in FIG. 21A). For the light load working, the rotational-movement center E is set at a position corresponding to a light load (the position shown in FIG. 21B). Further, the lock means 540 performs an unlocking operation before the link rotational-movement center changing means 510 is operated. It then performs a locking operation after the change has been completed. The change commanding means 620 may cause the link rotational-movement center changing means 510 to change the rotational-movement center E according to an operation of a switch 660 or to perform this changing operation according to either the command from the working program 650 or the operation of the switch 660. To cause the link rotational-movement center changing means 510 to perform the changing operation, the change corresponding motor angle control means 630 provides such control as drives the motor 13 to rotate the crank shaft 3 through a predetermined angle. This predetermined angle is such that the crank shaft 3 is rotated so that the position of the ram 6 is not markedly changed after an operation of changing the position of the rotational-movement center E to cause the pivoting link 5 to pivot to elevate or lower the ram 6. The lock confirming and working permitting means 640 inhibits the motor 13 from being driven before the link rotational-movement center changing means 510 changes the rotational-movement center E of the restraining link 8. The lock confirming and working permitting means 640 then permits the motor 13 to be driven after confirming that the changed position has been fixed. Specifically, the lock confirming and working permitting means 640 permits the motor 13 to be driven after confirming that the lock member 560 of the lock means 540 has engaged with the engaged portion 550 of the rotational moving member 520. The lock confirming and working permitting means 640 recognizes that the lock member 560 has engaged with the engaged portion, on the basis of a signal from detecting means 580 indicating the detection of movement of the lock driving means 570 to a predetermined position. The detecting means 580 may be omitted so that the driving of the motor 13 may be permitted a predetermined time after the change commanding means 620 has outputted a command for a lock operation to the lock driving means 570. The lock confirming and working permitting means 640 inhibits the motor 13 from being driven when, for example, the change commanding means 620 outputs an unlock command to the lock means 540. A description will be given of a control operation performed by the working control means 610 to change the position of the rotational-movement center. For heavy load working, in response to a predetermined command from the working program 650 or a signal from the switch 660, the change commanding means 620 commands the link rotational-movement center changing means 510 to set the rotational-movement center E of the restraining link 8 at the heavy load corresponding position (shown in FIG. 21A). At this position, the ram displacement curve HA shown in FIG. 22 is obtained as described above. Accordingly, the ram 6 lowers at a low speed to enable high-quality punch working. For light load working, in response to a predetermined command from the working program 650 or a signal from the switch 660, the change commanding means 620 commands the link rotational-movement center changing means 510 to set the rotational-movement center E of the restraining link 8 at the light load corresponding position (shown in FIG. 21B). At this position, the ram displacement curve HB shown in FIG. 22 is obtained. Accordingly, the ram 6 lowers at a high speed, thus enabling high-quality punch working. To use the change commanding means 620 to cause the link rotational-movement center changing means 510 to perform a changing operation, the lock means 540 unlocks the rotational moving member 520 and then the actuator 530 rotationally moves the rotational moving member 520 through a predetermined angle. This rotational movement causes the different engaged portion 550 of the rotational moving member 520 to face the lock member 560. Subsequently, the lock means 540 engages the lock member 560 with the engaged portion 550 to lock the rotational moving member 520 so that the member 520 cannot be rotated. By thus using the lock means 540 to lock the rotational moving member 520, the rotational-movement center E of the restraining link 8 is prevented from being moved by a load or the like during working. The lock confirming and working permitting means 640 inhibits the working control means 610 from driving the motor 13 when the rotational moving member 520 is unlocked. It permits the motor 13 to be driven when the detecting means 580 detects that the lock means 540 has been brought into a locking condition. In this manner, the motor 13 is permitted to be driven for punch working after the position of the rotational-movement center E has been fixed. This prevents punch working from being carried out when the locking effect is insufficient or the rotational-movement center E is incompletely positioned. Therefore, safety is ensured. In connection with the above the changing operation, a description has been given only of a change from heavy load position to light load position. The same operations as those described above are performed to change the light load position to the heavy load position except that the rotational moving direction of the rotational moving member 52 is reversed. Further, when the link rotational-movement center changing means 510 rotationally moves the rotational moving means 520, the change corresponding control means 630 causes the motor 13 to rotate the crank shaft 3 through a predetermined angle. That is, when the position of the rotational-movement center E at the proximal end of the restraining link 8 is changed, it must be changed on an arc around the third connecting portion P3 in order to change the position of proximal end of the restraining link 8 without elevating or lowering the ram 6. This is because the leading end of the restraining link 8 is connected to the third connecting portion P3 of the pivoting link 5. When the position is to be changed on such an arc, the configuration of the link rotational-movement center changing means 510 is limited. Consequently, this operation cannot be handled by the configuration according to this embodiment in which the support shaft 12 is eccentrically provided on the rotational moving member 520. The provision of the change corresponding motor angle control means 630 enables the position of the rotational-movement center E at the proximal end of the restraining link 8 to be changed by rotating the crank shaft 3 by an amount corresponding to the pivoting of the pivoting link 5 or the elevation or lowering of the ram 6 associated with the change, i.e. causing the motor 13 to rotate the crank shaft 3 through a predetermined angle, in spite of use of an arbitrary path for changing the position of the pivoting center E. Consequently, the operation of the link rotational-movement center changing means 510 is not limited, thus increasing the degree of freedom of design of the link rotational-movement center changing means 510. This results in the simple configuration in which the support point shaft 12 is eccentrically provided on the rotational moving member 520. Yet another embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 23, this motor driven link press is composed of a link press main body 151 that is a mechanical part and a control device 152 that controls the link press main body 151. The link press main body 151 comprises ram driving means 153 that drives the elevation and lowering of the tool driving ram 6 at a predetermined position, and plate material moving means 29 that moves a plate material as a workpiece below the ram 6. The ram driving means 153 is of a link type having the link mechanism 1. In FIG. 23, the control device 152 is composed of a computerized numerical control device (NC device) and a programmable controller. It is of a program controlled type that decodes and executes a working program 155. The control device 152 comprises plate material movement control means 157 that controls the plate material moving means 29, ram axis control means 158 that controls the motor 13 for the ram driving means 153, parallel synchronization control means 159 that synchronously controls both control means 157, 158, sequence control means (not shown in the drawings) that controls various types of sequence control of the link press main body 151, and decode executing means 156 that decodes the working program 155 and provides commands from the working program 155 to the control means 157, 158, 159, . . . . The working program 155 is stored in a program memory (not shown in the drawings) of the control device 152 or is externally loaded into the decode executing means 156. The working program 155 is described in terms of NC codes or the like. It contains the descriptions of X- and Y-axis movement commands that are plate material movement commands to cause the plate material moving means 29 to move the plate material in the directions of the X- and Y-axes, respectively, punch commands to elevate or lower the ram driving means 153, sequence commands (not shown in the drawings) to control the sequence operation of each portion of the link press main body 151, and other commands. The movement command for each axis and the punch command are provided, for example, as one block commands. Further, the working program 155 has information on the board thickness in its attribute information storage section. The plate material movement control means 157 controls an X- and Y-axis servomotors 141, 142 in the plate material moving means 29 via servo controllers 161, 162 for the respective axes. The plate material movement control means 157 provides trapezoidal control such that a plate material moving speed exhibits a trapezoidal speed curve VW comprising an acceleration section with a constant acceleration, a constant speed section, and a deceleration section with a constant deceleration as shown in FIG. 23C. If the moving distance of the plate material is short, the speed is reduced before reaching that of the constant-speed movement, resulting in a triangular speed curve VW. In this figure, the plate material moving distance is indicated by the area of trapezoidal or triangular portion of the plate material movement speed curve VW. The plate material control means 157 gives a movement command by, for example, outputting pulses. It changes the speed by changing a pulse distribution frequency. In this case, the servo controllers 161, 162 are digital servomechanisms that control a motor current according to an input pulse train. Specifically, the plate material movement control means 157 is composed of a speed pattern generating section 157a and a pulse distributing section 157b as shown in FIG. 27. The speed pattern generating section 157a is means for generating a speed pattern corresponding to the above trapezoidal or triangular speed curve VW, according to a preset maximum speed and preset acceleration and deceleration time constants as well as the plate material moving distance (in other words, a table positioning pitch). The pulse distributing section 157b is means for distributing pulses according to the set speed curve VW in order to drive the motor. In FIG. 27, a change in pulse distribution frequency is indicated by the height of the pulse. In this embodiment, the plate material movement control means 157 generates a speed pattern for each of the X- and Y-axes. However, it may generate a speed pattern so as to synchronize movements along the X- and Y-axes. In FIG. 23, the ram axis control means 158 controls the motor 13 for the ram driving means 153 via a servo controller 163. The ram axis control means 158 controls the ram speed by rotating the motor 13 in one direction and controlling the rotation speed of the motor 13. Specifically, the ram axis control means 158 distributes pulses according to a given ram rotation speed pattern VP in order to drive the motor as shown in FIG. 27. In FIG. 23, the parallel synchronization control means 159 gives commands to the ram axis control means 158 so that the operation in which the punch tool 31 driven by the ram 6 to elevate and lower moves from a height DP (FIG. 24) corresponding to a time immediately after it has left the top surface of the plate material, through the top dead center TDC to a height TP close to the top surface of the plate material is in parallel with the movement of the plate material from start till arrival at the next working point, the movement being effected by the plate material moving means 29. As shown in a specific example later, the parallel synchronization control means 159 controls the speed by maintaining a constant acceleration both during acceleration and during deceleration. The parallel synchronization control means 159 provides such control as avoids zeroing the speed of the motor 13 if the time required for the plate material movement from start till arrival at the next working point is shorter than a set time. If any maximum speed and acceleration and deceleration time constants have been specified for the motor 13, this set time is determined by these maximum speed and acceleration and deceleration time constants. Specifically, the parallel synchronization control means 159 has a table and ram synchronization interpolating section 159a and a generating section 159b that generates a ram axis motor speed pattern VP, as shown in FIG. 27. The table and ram synchronization interpolating section 159a is means for calculating, from the plate material moving speed curve VW generated by the plate material movement control means 157, the time required for the plate material movement from start till arrival at the next working point, the movement being effected by the plate material moving means 29. The plate material moving time is required for movement along both X- and Y-axes. If the moving time on the X-axis is different from the moving time on the Y-axis, the longer is determined to be the plate material moving time. The ram axis motor speed pattern generating section 159b is means for generating the speed pattern VP of the motor 13 for one rotation of the crank shaft 2. The motor speed pattern VP is composed of a motor speed pattern VP1 for plate material non-contact corresponding to the operation in which the punch tool 31 driven by the ram 6 to elevate and lower moves from the height DP (FIG. 24) corresponding to the time immediately after it has left the top surface of the plate material, through the top dead center TDC to the height TP close to the top surface of the plate material W, and a motor speed pattern VP2 for plate material contact following the motor speed pattern VP1 and corresponding to the operation in which the punch tool 31 moves from the height TP close to the top surface through the bottom dead center BDC to the height DP corresponding to the time immediately after the leaving. The ram axis motor speed pattern generating section 159b generates the motor speed pattern VP1 for plate material non-contact so that the operation in which the punch tool 31 moves from the height DP corresponding to the time immediately after the leaving through the top dead center RDC to the height TP close to the top surface is performed in the plate material moving time obtained. by the table and ram synchronization interpolating section 159a. That is, the motor speed pattern VP1 is generated so that the plate material moving time equals the time required for a ram operation from the height DP corresponding to the time immediately after the leaving to the height TP close to the top surface. The motor speed pattern VP1 is generated so that the speed is the maximum one Vm at the height DP (FIG. 28) corresponding to the time immediately after the leaving, subsequently gradually decreases, then maintains a constant speed, and increases again to the maximum one (Vm) at the height TP close to the top surface. This generation is carried out according to the preset maximum speed Vm and acceleration and deceleration time constants. The acceleration and deceleration time constants have, for example, a fixed value. If the acceleration an deceleration time constants are fixed, the ram axis motor speed pattern VP1 for plate material non-contact constitutes a speed curve which is basically inversely trapezoidal and which is composed of a deceleration portion VPa, a constant-speed portion VPb, and an acceleration portion VPc. If the plate material moving time is short, then the ram operation time is short. Accordingly, the speed pattern VP1 is free from the constant-speed pattern VPb and is thus V-shaped. The ram axis motor speed pattern VP2 for plate material contact indicates the fixed maximum speed Vm. The maximum speed Vm is properly set at a value suitable for punch working. If the ram axis motor speed pattern generating section 159b generates the motor speed pattern VP1 as described above, when the plate material moving time is long, the motor speed decreases to zero. This is because the acceleration and deceleration time constants are fixed. The speed is maintained at zero and then increased. The time required for the maximum speed Vm to decrease to zero corresponds to the above set time. If the time required for the plate material movement from start till arrival at the next working point is shorter than the above set time, the parallel synchronization control means 159 provides such control as avoids zeroing the speed of the motor 13. To start punch working when the ram is stopped at the top dead center or the like, the ram axis motor speed pattern generating section 159b generates a speed pattern in which, during the first single ram operation, the ram 6 moves from the angle of rotation of the motor set during stoppage through the height TP close to the top surface and the top dead center TDC to the height DP corresponding to the time immediately after the leaving. Further, the parallel synchronization control means 159 provides such control as synchronizes the start of the plate material movement effected by the plate material moving means 29 with the ram operation. This synchronization is carried out by providing a signal to the plate material movement control means 157 to start the plate material movement when the punch tool 31 reaches the height DP corresponding to the time immediately after the leaving after having wrought the plate material W. This synchronization control is executed, for example, by the table and ram synchronization interpolating section 159a. An appropriate detecting means provided in the link mechanism 1, the ram 6, or the like can detect that the punch tool 31 has reached the height DP corresponding to the time immediately after the leaving. The height DP (FIG. 24) corresponding to the time immediately after the leaving and the height TD close to the top surface are each a height position located a set excess distance above the surface of the plate material W. The set excess distance can be arbitrarily set. The set excess distance for the height DP corresponding to the time immediately after the leaving may have a value different from that of the set excess distance for the height TD close to the top surface. The position of surface of the plate material W is obtained from information on the thickness of the plate material set in the working program 155. The surface position of the plate material W may be, for example, that of the thickest plate material wrought by this motor driven link press and may have a fixed value. A pre-reading function of the working program 155 provided in the plate material movement control means 157, parallel synchronization control means 159, or decode executing means 156 is used for the generation of a plate material moving speed pattern by the plate material movement control means 157 as well as the generation of a ram axis motor speed pattern by the parallel synchronization control means 159. For example, while the plate material movement control means 157 or the ram axis control means 158 is distributing pulses according to a block of the working program 155 being executed, a plate material moving speed pattern or a ram axis motor speed pattern is generated in response to a command in a pre-read block of the working program 155. FIG. 26 shows an example of structure of the working program 155. The working program 155 is composed of a list of sequentially executed blocks B as shown in FIG. 26. One or more commands such as a plate material movement command Ba or a tool command Bb are described in each block B. The plate material movement command Ba describes movement following a code (X, Y, or the like) indicative of a moving direction. For a punch press, in most cases, the plate material movement command Ba causes a portion of the plate material to be punched to be moved to the ram position. Thus, in this example, the block B containing the plate material movement command Ba means that a punch operation is performed after the plate material has been moved. Thus, for the blocks B that do not cause any punch operations to be performed after the movement of the plate material, the plate material movement command Ba is followed by a command expressed by an M code or the like and which inhibits the punch operation. Accordingly, the decode executing means 56 in FIG. 23 considers the blocks B containing the plate material movement command Ba (FIG. 26) from the working program 155 to contain a punch command unless the non-punch command is added to them. The plate material movement control means 157, ram axis control means 158, and parallel synchronization control means 159 of the control device 152, described with reference to FIG. 23, are composed of a computer 152A constituting the control device 152 and a plate material movement and punch operation control program 170 as shown in FIG. 25. The plate material movement and punch operation control program 170 may be stored in a storage medium 171 from which the program 170 may be read by a storage medium reading device (not shown in the drawings) of the computer 152A. The storage medium 171 is, for example, a compact disk or a magneto optic disk. Alternatively, the plate material movement and punch operation control program 170 may be stored in another computer that may provide the program 170 to the computer 152A via a communication line. A description will n given of the relationship between the plate material movement and the ram operation, both controlled by the control device 152. It is assumed that while the plate material is being moved as shown by a speed curve VW1 at the left end of FIG. 28A, the decode executing means 156 (FIG. 23) pre-reads a block B from the working program as shown in FIG. 27. At this time, the table positioning pitch, i.e. the plate material moving distance to the next working point, is decoded from the block B. On the basis of the set maximum speed and acceleration and deceleration time constants, the positioning speed pattern generating section 157a of the plate material movement control means 157 generates a speed curve VW according to which the plate material is moved over the decoded plate material moving distance. The speed curve VW is normally trapezoidal but is triangular if the moving distance is short. The plate material movement control means 157 subsequently uses a predetermined timing to cause the pulse distributing section 157b to distribute pulses according to the generated speed curve VW to allow the plate material moving means 29 to move the plate material. This movement is based on the second speed curve VW2 from the left end of FIG. 28A. The predetermined timing is a point of time at which the detecting means (not shown in the drawings) detects that, after the last working carried out by elevating and lowering the ram 6, the punch tool 31 has reached the height DP corresponding to the time immediately after the punch tool 31 has left the plate material W. Once the positioning speed pattern generating section 157a generates the speed curve VW2, the parallel synchronization control means 159 uses the table and ram synchronization interpolating section 159a to calculate the time required for the plate material movement. The parallel synchronization control means 159 also uses the ram axis motor speed pattern generating section 159b to generate a motor speed pattern VP for the ram axis. The motor speed pattern VP is a combination of the motor speed pattern VP1 for plate material non-contact corresponding to the operation in which the punch tool 31 moves from the height DP (FIG. 24) corresponding to the time immediately after it has left the top surface of the plate material, through the top dead center TDC to the height TP close to the top surface of the plate material W, and the motor speed pattern VP2 for plate material contact following the motor speed pattern VP1 and corresponding to the operation in which the punch tool 31 moves from the height TP close to the top surface through the bottom dead center BDC to the height DP corresponding to the time immediately after the leaving. In FIG. 28B, the motor speed pattern VP corresponds to a time T1. The motor speed pattern VP1 for plate material non-contact is generated so that the operation from the height DP corresponding to the time immediately after the leaving to the height TP close to the top surface is performed exactly in the plate material movement time. This generation is carried out according to the preset maximum speed Vm and acceleration and deceleration time constants. The motor speed pattern VP1 is generated so that the speed is the maximum one Vm at the height DP (FIG. 28) corresponding to the time immediately after the leaving, subsequently gradually decreases, then maintains a constant speed, and increases again to the maximum one Vm at the height TP close to the top surface. The ram axis motor speed pattern VP1 for plate material non-contact is basically inversely trapezoidal. If the plate material moving time is short, then the ram operation time is short. Accordingly, the speed pattern VP1 is free from the constant-speed pattern VPb and is thus V-shaped. The ram axis motor speed pattern VP2 for plate material contact indicates the fixed maximum speed Vm. The thus generated ram axos motor speed pattern VP is outputted to the ram control means 158. After the ram axis motor speed pattern VP for the last punch operation has ended, the ram axis control means 158 drives the motor by distributing pulses according to the generated ram axis motor speed pattern VP. The last ram axis motor speed pattern VP ends when the punch tool 31 reaches, after punch working, the height DP corresponding to the time immediately after the punch tool 31 has left the plate material W. Accordingly, control based on the current ram axis motor speed pattern VP is carried out after the height DP corresponding to the time immediately after the leaving. Such control is repeated while sequentially pre-reading the blocks B of the working program 155. Such control causes the operations described below to be performed. That is, the ram driving motor 13 is always rotated in one direction. The crank shaft 2 of the link mechanism 1 is thus always rotated in one direction as shown in FIG. 23B. The ram 6 executes punch working on the plate material W while lowering from the height TD close to the top surface to the bottom dead center. BCD. At the height TD close to the top surface, the ram speed is preferable for punch working. This preferable speed is maintained during lowering to the bottom dead center BDC and during elevation from the bottom dead center BDC to the height DP corresponding to the time immediately after the leaving. Further, during these operations, the plate material W remains stopped. Once the punch tool 31 elevates to the height DP corresponding to the time immediately after the leaving, the plate material moving means 29 starts moving the plate material W. Once the plate material movement is completed, the punch tool 31 reaches the height TD close to the top surface. In this manner, during the plate material movement, synchronous control is provided so that a ram operation is performed so as not to bring the tool into contact with the plate material W. This eliminates useless standby time to minimize the cycle time. Further, the cycle time can be reduced without reciprocating the crank shaft 3. Further, after the crank shaft 3 has been rotated in one direction to elevate the tool from the height DP corresponding to the time immediately after the leaving and before the tool reaches the height TD close to the top surface, the ram axis control means 158 attempts to avoid stopping the ram 6 according to the speed pattern VP provided by the parallel synchronization control means 159. That is, the parallel synchronization control means 159 provides a speed pattern VP that avoids zeroing the speed of the motor 13 if the time required for the plate material movement is shorter than the set time. This reduces an acceleration load on the punch driving servomotor 13, thus minimizing acceleration and deceleration energy. This in turn serves to accomplish a reduced cycle time, i.e. an increased hit rate and the saving of punch driving energy. For example, as shown in the comparative example in FIG. 29B, compared to such control as starts a punch operation a predetermined time before the stoppage of the plate material movement, high acceleration or deceleration is not required to drive the ram. This prevents the driving of the motor from consuming more energy for acceleration and deceleration. In generating a motor speed pattern VP, the parallel synchronization control means 159 sets a constant acceleration both for acceleration and for deceleration. Consequently, the calculation of a motor speed pattern VP by the computer 152A, constituting the control device 152, constitutes a light load. The calculation can thus by promptly executed by a relatively simple computer 152A. Further, the motor speed pattern VP is trapezoidal and has the constant-speed pattern portion VPb. Consequently, the speed does not change rapidly, and the ram 6 can be smoothly elevated and lowered while no punch operations are performed. Therefore, vibration and impact can be weakened. In the above embodiment, the motor speed pattern VP is trapezoidal so as to accomplish linear acceleration and deceleration. However, the motor speed pattern VP may be adapted for curved acceleration and deceleration (so-called S-shaped acceleration and deceleration). Still another embodiment of the present invention will be described below with reference to the drawings. FIG. 30 is an exploded front view of a link mechanism in this servomotor driven link press. FIGS. 32A to 32D show various examples of tools used in this servomotor driven link press and driven by the ram 6. FIG. 32A shows an example of a punch working tool, the punch tool 31 and die tool 32. FIG. 32B shows a forming tool. An upper tool 31B has a concave forming-die surface 31Ba. A lower tool 32B has a convex forming-die surface 32Ba. The upper tool 31B is lowered by the ram 6 (FIG. 1) to form a formed portion Wa on the plate material workpiece W between the forming-die surfaces 31Ba, 32Ba of the upper and lower tools 31B, 32B. FIG. 32C shows an example of a rotary tool. An upper tool 31C and a lower tool 32C have a working rollers 31Ca, 32Ca, respectively, that can each be rotated around its axis orthogonal to the central axis of the tool. The upper tool 31C is lowered to a predetermined height position by the ram 6 to sandwich the plate material workpiece W between both working rollers 31Ca, 32Ca. A groove-like formed portion is thus formed in the plate material workpiece W. The working rollers 31Ca, 32Ca may sandwich the plate material workpiece W between themselves to cut it. FIG. 32D shows an example of a cut working tool. An upper tool 31D has a cutting tool 31Da, and a lower tool 32D is a table on which the plate material workpiece W is placed. The upper tool 31D is lowered to a predetermined height position by the ram 6 so that the cutting tool 31Da cuts into the plate material workpiece W down to the middle of its board thickness. Then, the plate material workpiece W is fed to cut a groove Wb in the plate material workpiece W. The tools 31B to 31D and 32B to 32D are installed on the above described tool supporting means 28. For example, the tools 31B to 31D are installed on the turret 28a, and the tools 32B to 32D are installed on the turret 28b, the turrets 28a, 28b constituting the tool supporting means 28. The control system will be described with reference to FIG. 30. This servomotor driven link press has servomotor control means 261 for controlling the servomotor 13 to stop the ram 6 at an arbitrary position within an elevating and lowering stroke of the ram 6. The servomotor control means 261 is composed of, for example, a computer constituting a numerical control device or the like which controls the whole servomotor driven link press. The servomotor control means 261 can switch the operation of the servomotor 13 between nonstop operation mode M1 in which the servomotor 13 is not stopped while the ram 6 is lowering and a lowering stop operation mode M2 in which the servomotor 13 is stopped while the ram 6 is lowering. Working switching means 262 is provided to supply the servomotor control means 261 with a command to switch the operation of the servomotor 13 between the nonstop operation mode M1 and the lowering stop operation mode M2. The working switching means 262 may be composed of, for example, a computer constituting the above described numerical control device or a switch provided on an operation panel. In the lowering stop operation mode M2, while the servomotor 13 is being rotated in a rotating direction in which the ram 6 moves at a lower speed during lowering than during elevation owing to the characteristics of the link mechanism 1, the servomotor control means 261 stops the servomotor 13 while the ram 6 is lowering to stop the ram at an arbitrary position within its elevating and lowering stroke. Further, in the lowering stop operation mode M2, after the stoppage, the servomotor is rotated in the opposite direction. That is, the motor is stopped and reversely rotated before the ram reaches the bottom dead center. After this reversal, when the ram 6 reaches the top dead center TDC or a predetermined elevated position, the motor is reversely rotated again, that is, it is switched to the original rotating direction. This servomotor driven link press uses the servomotor 13 as a driving source and can thus stop the ram 6 at an arbitrary position. Because of these characteristics of the motor and the use as motor control means of the servomotor control means 261, which controls the servomotor 13 to stop the ram 6 at an arbitrary position within its elevating and lowering stroke, this embodiment can stop the ram 6 at an arbitrary position to carry out various types of working, though it is of a link type. For example, it is possible to execute the forming in FIG. 32B, the working with the rotary tools 31C, 32C in FIG. 32C, or the cutting of the groove Wb with the cutting tool 31Da in FIG. 32D. If the forming in FIG. 32B is carried out, it is possible to change the protruding height of the formed portion Wa formed on the plate material workpiece W by controlling the stopped position of the ram 6 to change the lowering stopped position of the upper tool 31B. In this case, after the ram 6 has been stopped, the rotating direction of the servomotor 13 is reversed to elevate the ram 6. If any of these types of working is carried out in which the ram 6 is stopped during lowering, the ram 6 lowers by only a short distance per unit rotation of the servomotor 13 because it is stopped during lowering operation in which it moves at a lower speed. Thus, the stopped position of the ram 6 can be more precisely controlled, thus enabling control within smaller ranges and thus more sophisticated working. If working is carried out in which the ram 6 is stopped during lowering, then after the stoppage, the servomotor control means 261 provides such control as reverses the rotating direction of the servomotor 13. In this case, as shown in FIG. 31, the servomotor 13 is reciprocated in a section U corresponding to a part of one rotation of the servomotor 13. This enables working in which the ram is not lowered to the bottom dead center. It is also possible to carry out working in which the ram 6 is allowed to stand by at a predetermined standby height instead of elevating to the top dead center. By switching the operation mode of the servomotor control means 261, the working switching means 262 can switch the type of working between the one in which the ram 6 is stopped during lowering and the one in which the ram 6 is not stopped during lowering. In this manner, control can be provided so as to freely switch among these types of working. The use of the servomotor 13 enables to motor speed to be freely changed. The speed can also be changed during an elevating and lowering stroke of the ram 6, enabling working to be accomplished according to various requirements. That is, a speed curve based on operations of a link mechanism composed of the crank member 2, pivoting link 5, restraining link 8, and the like is used as a basic speed curve observed if the servomotor 13 is rotated at a uniform speed, and the motor speed is varied. Then, for example, the speed at which the punch tool 31 contacts with the plate material workpiece W is reduced to make operations more silent. Alternatively, the elevating speed can be further increased. Further another embodiment of the present invention will be described with reference to the drawings. FIG. 33 is a combination of a view of a link mechanism in this link type punch press and a block diagram showing a conceptual configuration of a control system. In FIG. 33, a control device 341 controls the whole link type punch press and is composed of a computerized numerical control device and a programmable controller both controlled by the working program (not shown in the drawings). The control device 341 has control means for each axis for driving the elevation and lowering of the ram 6 or controlling the workpiece feeding means 29. One of these control means is ram axis control means 344. The ram axis control means 344 controls the motor 13, which drives the crank shaft of the link mechanism 1. The ram axis control means 344 has motor rotating-direction control means 344 that switches the rotation of the motor 13 between a forward and backward directions, and motor rotating-speed control means 345 for controlling the rotation speed of the motor 13. The control device 341 has working type selecting means 342. The motor rotating-direction control means 344 switches the rotation of the motor 13 between the forward and backward directions depending on the type of working selected by the working type selecting means 342. The working type selecting means 342 selects a type of punch working quality to provide information indicating that, for example, either normal working or high-quality working has been selected. In this example, it is possible to select one of three levels including the normal working and high-quality working as well as ultra-high-quality working. The motor rotating-direction control means 344 switches the rotation of the motor 13 between the forward and backward directions depending on the type of working selected by the working type selecting means 342. If the working type selecting means 342 selects the normal working as a type of working, the motor rotating-direction control means 344 sets the rotation of the motor 13 to the forward direction, i.e. the direction in which rotation is transmitted via the link mechanism 1 to make the lowering speed of the ram 6 lower than its elevating speed. The opposite rotating direction is set for the high-quality working. The motor rotating-direction control means 344 also sets the opposite rotating direction if the working type selecting means 342 selects the ultra-high-quality working. The motor rotation speed control means 345 is provided with a function of detecting predetermined information to increase the rotation speed of the motor so as to further increase the lowering speed of the ram 6 if the motor rotating-direction control means 344 sets the motor rotating direction in which the lowering speed of the ram 6 is higher than its elevating speed. In controlling the motor to increase its rotation speed so as to further increase the lowering speed of the ram 6, the motor rotation speed control means 345 may increase the speed in all sections corresponding to one rotation of the crank member 2 or in only the ram lowering section during one rotation of the crank member 2. The predetermined information indicates that, for example, the working type selecting means 342 has selected the ultra-high-quality working as a type of working. Specifically, the working type selecting means 342 may be working type selection information described in the working program, information set in parameter setting means (not shown in the drawings) or the like, or information inputted from the operation panel by an operator. The working type selection information described in the working program may be provided as a command using an NC code or the like or may be attribute information. The type of punch working quality has only to allow the type of punch working quality to be identified. Alternatively, the control device 341 may recognize information on the material of the plate material, the type of surface treatment, and the like as working type selection information and may transmit this information to the motor rotating-direction control means 344. A description will be given of operations of the control device 341 configured as described. When the working type selecting means 342 selects the normal working, the motor rotating-direction control means 344 rotates the motor 13 in the forward direction. Thus, as previously described with reference to FIG. 34A, the ram 6 operates at a lower speed during lowering than during elevation. This enables punch working with a low torque. If the working type selecting means 342 selects the high-quality working, the motor rotating-direction control means 344 rotates the motor 13 in the opposite direction. Thus, the lowering speed of the ram 6 is increased as shown by a curve Ha in FIG. 34B. Consequently, high-quality punch working can be accomplished. That is, punch working can be accomplished with few burrs. However, in this case, a heavy press load cannot be obtained, so that a plate material workpiece with a large board thickness cannot be punched. Further, punch working cannot be achieved in which a hole with a large diameter is formed. It is thus possible to freely select either the normal working, in which a plate material workpiece with a large board thickness can be punched or a hole with a large diameter can be formed, or the high-quality working, which can accomplish high-quality working in spite of limits on the efficiency, board thickness, hole diameter, or the like. When the working type selecting means 342 selects the ultra-high-quality working, the motor rotating-direction control means 344 rotates the motor 13 in the opposite rotating direction. The motor rotation speed control means 345 increases the rotation speed to further increase the lowering speed of the ram 6. A curve Hb in FIG. 34B indicates a speed curve for the ram 6 in this case. Thus lowering the ram 6 faster enables higher-quality working. In this case, stricter limits are imposed on the board thickness and the hole diameter. However, if they are within corresponding allowable ranges, higher-quality working can be accomplished. The motor driven link press of the present invention employs the link mechanism having the crank member, pivoting link, connecting rod, and restraining link. Consequently, even with a motor with relatively low output power, it is possible to carry out working with a heavy press load and improve the working cycle time. Further, even though the link mechanism is employed, the drive transmitting system that controls the rotation of the motor to controllably transmit the elevating and lowering operations of the ram is employed to transmit rotational driving effected by the motor to the crank shaft of the link mechanism. That is, this drive transmitting system does not include any parts such as a flywheel which are intended to apply inertia. Therefore, this motor drive link press can be properly controlled easily. If a servomotor is used as this motor, it is possible to freely control the operation speed to accomplish various types of working while making the best of advantages of the link press. If this motor driven link press is applied to a punch press, when the intermediate section of lowering process of a electing and lowering stroke of the ram is used as that section of elevating and lowering stroke of the ram which is used to punch the plate material workpiece, a sufficient stroke can be provided below the bottom surface of the plate material workpiece. This ensures that punching scraps are dropped. | <SOH> BACKGROUND OF THE INVENTION <EOH>In mechanical punch presses, a crank mechanism is commonly used as a slide driving mechanism that converts a rotating operation of a motor into an elevating or lowering operation of a ram. Further, a flywheel is used, and a clutch is let in or released to rotate or stop the flywheel to drive or stop the ram. With the crank mechanism, curves for the elevating and lowering speeds of the ram are symmetric with respect to a bottom dead center. The lowering speed is thus the same as the elevating speed. However, for general press working including punch working, the ram preferably moves at lower speed during lowering in order to make the lowering operation silent or because of a requirement for a press load. However, the elevating operation is not particularly limited and is thus preferably faster. With a crank mechanism in which the lowering speed is the same as the elevating speed, it takes more time than required to achieve elevation. This increases a cycle time for punch working. Recently, apparatuses have been proposed which use a servomotor as a driving source to elevate and lower the ram via a crank mechanism without using any flywheels. The servomotor can freely change the speed of the ram during its stroke and can increase its lowering speed while reducing its elevating speed. However, the capabilities of the motor depend on its rotation speed. The motor must be operated within the range of the optimum motor rotation speed according to the characteristics of the motor. If the rotation speed of the motor is controlled so that the lowering speed differs from the elevating speed, it is impossible to make full use of capabilities of the motor. A large-sized motor is required to increase the elevating speed while obtaining a required press load. The applicant thus examined various slide mechanisms in order to select an appropriate slide mechanism that enables the ram to lower at a low speed while elevating at a high speed. A link press has long been used as a slide mechanism used for a press device for plastic forming such as cold extrusion or upsetting of metal (for example, the Examined Japanese Patent Application Publication (Tokkou-Hei No. 3-42159). The link press comprises a pivoting link connected to a crank pin of a crank mechanism and to which a connecting rod and a restraining link are connected. The crank shaft is driven by a motor via a flywheel. With this link press, the restraining link serves to characterize the operation of the ram so that the ram lowers at a low speed and elevates fast. However, the conventional link press is used to improve the quality of plastic forming such as cold extrusion by utilizing its very slow lowering operation performed near a bottom dead center. Thus, no conventional link presses have been applied to a punch press for which operational characteristics different from those for plastic forming are required. Further, the conventional link press is provided with a flywheel that stores output power from the motor as inertia energy. Consequently, it is difficult to properly control the conventional link press easily. It is thus an object of the present invention to provide a motor driven link press which enables working with a heavy press load and also enables a working cycle time to be improved even when a motor with a relatively low output power is used and which can be properly controlled easily. It is another object of the present invention to freely control an operation speed to accomplish various types of working while making use of advantages of the link press. It is yet another object of the present invention to ensure punching scraps are dropped when the link press is applied to a punch press. | <SOH> SUMMARY OF THE INVENTION <EOH>A motor driven link press according to the present invention a motor, a link mechanism that converts rotating operation transmitted by the motor via a drive transmitting system, into a linear operation, and a ram installed below the link mechanism to elevate and lower for press working on the basis of this linear operation. The link mechanism comprises a crank member having a crank shaft and an eccentric shaft portion, a pivoting link having a first to third connecting portions located at vertices of a triangle and which are used for rotatable connections, the first connecting portion being connected to the eccentric shaft portion of the crank member, a connecting rod having opposite ends connected to the second connecting portion and an upper end of the ram, respectively, and a restraining link having a proximal end rotationally movably connected to a frame and a leading end connected to the third connecting portion of the pivoting link, the restraining link restraining pivoting of the pivoting link so that a lowering operation of the ram is slower than an elevating operation of the ram when the crank shaft is rotated at a fixed speed in one direction. The drive transmitting system controls rotation of the motor to transmit rotational driving effected by the motor to the crank shaft so that an elevating and lowering operations of the ram can be controlled. The drive transmitting system includes no parts such as a flywheel which are intended to apply inertia. The drive transmitting system may have a speed reducer or an output shaft of the motor and the crank shaft may be directly coupled together. The operation of this configuration will be described. The crank shaft is rotated to cause the pivoting link to perform a composite operation including a revolving operation along a turning locus of axis of the eccentric shaft portion and rotational motion in which the pivoting link pivots back and forth because the restraining link is connected to the pivoting link. The revolving operation of the pivoting link elevates or lowers the connecting rod connected to the pivoting link. However, the rotational motion hinders an elevating and lowering speed curve for the lower end position of the connecting rod, i.e. the ram position, from being quasi-sinusoidal. The curve for a lowering operation and the curve for an elevating operation are thus asymmetric. Which of the lowering and elevating operations is faster depends on a combination of various elements such as the support point position and length of the restraining link. Thus, these elements can be properly designed to allow the restraining link to regulate the pivoting of the pivoting link so that the lowering operation of the ram is slower than its elevating operation when the crank shaft is rotated at a fixed speed in one direction. By thus reducing the lowering speed, it is possible to accomplish working with a heavy press load and increase the lowering speed even when a motor with a relatively low output power is used. This improves a working cycle time. The above speed change can be accomplished with a fixed motor speed. Thus, for example, a speed reducer with an appropriate reduction ratio can be used to operate the motor with a motor rotation speed providing the maximum motor output power according to its characteristics. This also allows a motor with lower output power to be used. Further, the motor and the crank shaft are connected together via the drive transmitting system including no inertia applying systems such as a flywheel. Thus, for example, it is easy to provide such control as a change in ram speed based on, for example, the control of rotation speed of the motor. If the above motor is a servomotor, the motor speed can be freely changed. Accordingly, the speed of the ram can be changed during its elevating and lowering stroke. This enables working according to various requirements. That is, a speed curve based on operations of a link mechanism composed of the crank mechanism, pivoting link, restraining link, and the like is used as a basic speed curve observed if the motor is rotated at a uniform speed, and the motor speed is varied. Then, for example, the speed at which the punch tool contacts with a workpiece can be reduced to make operations more silent. Alternatively, the elevating speed can be further increased. The motor driven link press of the present invention may be a punch press. In this case, that section of elevating and lowering stroke of the ram which is used to punch a plate material workpiece is an intermediate section of lowering process of the elevating and lowering stroke. The section used for punching is determined by the relationship between the height of a table on which the plate material workpiece is placed and the ram position and the installation heights of a punch and a die tool, or the like. If the intermediate section of elevating and lowering stroke of the ram is thus used as a punching section, a sufficient stroke can be provided below the bottom surface of the plate material workpiece. This ensures that punching scraps are dropped. | 20050126 | 20060418 | 20050623 | 61131.0 | 0 | NGUYEN, JIMMY T | MOTOR DRIVEN LINK PRESS | UNDISCOUNTED | 1 | CONT-ACCEPTED | 2,005 |
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11,041,972 | ACCEPTED | Catalyst-supported body and fuel cell using the same | A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200, and exhibiting high activity per unit amount of a catalyst metal, a low reaction resistance and an improved output density, and is useful for a fuel battery; a production method thereof and a fuel battery using the catalyst carrier. | 1. A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200. 2. The catalyst carrier as claimed in claim 1, wherein a ratio of an average fiber length after the crushing treatment to an average fiber length before the crushing treatment is 0.8 or less. 3. The catalyst carrier as claimed in claim 1, wherein a ratio of a specific surface area after the crushing treatment to a specific surface area before the crushing treatment is 1.1 or more. 4. The catalyst carrier as claimed in claim 1, wherein the vapor-grown carbon fiber is a carbon fiber comprising a branched vapor-grown carbon fiber. 5. The catalyst carrier as claimed in claim 1, wherein the catalyst metal is at least one metal selected from the group consisting of platinum and transition metals belonging to the groups IV and V in the periodic table or any one of alloys thereof. 6. A production method for a catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction is supported on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been obtained by thermally decomposing hydrocarbon, or a vapor-grown carbon fiber obtained by performing a thermal treatment of the thus-obtained vapor-grown carbon fiber at a temperature of from 600° C. to 1300° C. in an atmosphere of an inert gas, which have been crushed so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200. 7. The production method for the catalyst carrier as claimed in claim 6, wherein support of the catalyst metal is performed by a liquid phase reduction method. 8. The production method for the catalyst carrier as claimed in claim 6, wherein, after being crushed, the vapor-grown carbon fiber is subjected to a thermal treatment at a temperature of from 2000° C. to 3000° C. in an atmosphere of an inert gas. 9. The production method for the catalyst carrier as claimed in claim 6, wherein, before being crushed, the vapor-grown carbon fiber is subjected to a thermal treatment at a temperature of from 2000° C. to 3000° C. in an atmosphere of an inert gas. 10. The production method for the catalyst carrier as claimed in claim 6, wherein such crushing is performed by dry crushing using an impact force. 11. The production method for the catalyst carrier as claimed in claim 10, wherein crushing is performed in an atmosphere containing oxygen in a concentration of 5% by volume or more. 12. A catalyst carrier obtained by the method as claimed in claim 6. 13. An electrode material, wherein a catalyst layer comprising a catalyst carrier as claimed in claim 1 is formed on an electrically conductive base material. 14. A membrane electrode assembly for a fuel battery, which comprises an electrode wherein a catalyst layer and a gas diffusion layer are provided on both faces of an electrolyte membrane, being characterized in that the catalyst layer comprises the electrode material as claimed in claim 13. 15. A cell of a fuel battery, comprising the membrane electrode assembly for the fuel battery as claimed in claim 14 which is sandwiched by separators. 16. A fuel battery, comprising two or more of the cells for the fuel battery as claimed in claim 15 being laminated one on another. | CROSS REFERENCE TO THE RELATED APPLICATIONS This is an application filed pursuant to 35 U.S.C. Section 111(a) with claiming the benefit of U.S. Provisional application Ser. No. 60/541,505 filed Feb. 4, 2004 under the provision of 35 U.S.C. Section 111(b), pursuant to 35 U.S.C. Section 119(e) (1). TECHNICAL FIELD The present invention relates to a catalyst carrier. More particularly, the present invention relates to a catalyst carrier, which can be used as an electrode catalyst of a fuel battery, wherein a catalyst metal is carried on a carbon fiber; a production method for the catalyst carrier; and a fuel battery using the catalyst carrier. BACKGROUND ART A solid polymer type fuel battery is attracting attention to be used for a cell automobile and a portable power supply since it is compact and can obtain a high current density when operated at room temperature compared with a phosphoric-acid type fuel battery and a molten carbonate type fuel battery. Further, many proposals on components, system compositions and the like in such fields have been made. A stack structure of a conventional solid polymer type fuel battery is a sandwich structure of, for example, of separator/electrode (oxygen electrode)/electrolyte membrane/electrode (hydrogen electrode)/separator. Required characteristics of an electrode for this fuel battery are to prevent the electrode from poisoning by carbon monoxide and to enhance activity per unit amount of a catalyst metal. For the purpose of preventing such poisoning and enhancing the activity, many trials have been made to date on metals or alloys thereof to be used as catalysts as described in JP-A-2001-85020 (U.S. Pat. No. 6,689,505), which describes that a particle size of a catalyst is preferably several nm. On the other hand, as for carbon to be used for a carrier, particulate carbon such as ordinary carbon black is used as described in JP-A-8-117598, JP-A-2003-201417 (EP 1309024) and JP-A-2001-357857. However, since the contact between carbon particles is conducted by a point contact, there is a problem that resistance is large and gas permeability is insufficient. In order to solve these problems, it has been considered effective to change the particulate carbon to fiber carbon to be used for the carrier as described in JP-A-7-262997, JP-A-2003-317742 and JP-A-2003-200052. As for carbon fibers, a vapor-grown carbon fiber, a carbon nanotube and a PAN type carbon fiber are known. However, in any of reports which have been made public to date, a technique to produce an electrode comprising a carbon fiber on which fine catalyst particles are uniformly carried with a high density has not been described. DISCLOSURE OF THE INVENTION An object of the present invention is to provide a vapor-grown carbon fiber capable of enhancing an activity per unit amount of a catalyst metal, reducing a reaction resistance and enhancing an output density and appropriate as a catalyst carrier and the like, a catalyst carrier carrying a metal catalyst, production methods thereof and an application thereof for a fuel battery. The present invention provides a catalyst carrier, a production method and an application thereof as follows: 1. A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200. 2. The catalyst carrier as described in 1 above, wherein a ratio of an average fiber length after the crushing treatment to an average fiber length before the crushing treatment is 0.8 or less. 3. The catalyst carrier as described in 1 or 2 above, wherein a ratio of a specific surface area after the crushing treatment to a specific surface area before the crushing treatment is 1.1 or more. 4. The catalyst carrier as described in any of 1 to 3 above, wherein the vapor-grown carbon fiber is a carbon fiber comprising a branched vapor-grown carbon fiber; 5. The catalyst carrier as described in any of 1 to 4 above, wherein the catalyst metal is at least one metal selected from the group consisting of platinum and transition metals belonging to the groups IV and V in the periodic table or any one of alloys thereof. 6. A production method for a catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction is supported on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been obtained by thermally decomposing hydrocarbon, or a vapor-grown carbon fiber obtained by performing a thermal treatment of the thus-obtained vapor-grown carbon fiber at a temperature of from 600° C. to 1300° C. in an atmosphere of an inert gas, which have been crushed so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200. 7. The production method for the catalyst carrier as described in 6 above, wherein support of the catalyst metal is performed by a liquid phase reduction method. 8. The production method for the catalyst carrier as described in 6 or 7 above, wherein, after being crushed, the vapor-grown carbon fiber is subjected to a thermal treatment at a temperature of from 2000° C. to 3000° C. in an atmosphere of an inert gas. 9. The production method for the catalyst carrier as described in 6 or 7 above, wherein, before being crushed, the vapor-grown carbon fiber is subjected to a thermal treatment at a temperature of from 2000° C. to 3000° C. in an atmosphere of an inert gas. 10. The production method for the catalyst carrier as described in any of 6 to 9 above, wherein such crushing is performed by dry crushing using an impact force. 11. The production method for the catalyst carrier as described in 10 above, wherein crushing is performed in an atmosphere containing oxygen in a concentration of 5% by volume or more. 12. A catalyst carrier obtained by the method as described in any of 6 to 11 above. 13. An electrode material, wherein a catalyst layer comprising a catalyst carrier as described in any of 1 to 5 and 12 above is formed on an electrically conductive base material. 14. A membrane electrode assembly for a fuel battery, which comprises an electrode wherein a catalyst layer and a gas diffusion layer are provided on both faces of an electrolyte membrane, being characterized in that the catalyst layer comprises the electrode material as described in 13 above. 15. A cell of a fuel battery, comprising the membrane electrode assembly for the fuel battery as described in 14 above which is sandwiched by separators. 16. A fuel battery, comprising two or more of the cells for the fuel battery as described in 15 above being laminated one on another. Further, the present invention also relates to a vapor-grown carbon fiber as follows: 17. A vapor-grown carbon fiber, being characterized by having on its surface a physical site capable of carrying a catalyst metal. 18. The vapor-grown carbon fiber as described in 17 above, wherein the physical site is a defect generated by a chemical and/or physical action. 19. The vapor-grown carbon fiber as described in 18 above, wherein the physical action is an action by an impact and/or shearing force. BRIEF DESCRIPTION OF THE DRWAINGS FIG. 1 is a schematic vertical cross-sectional diagram showing a structure in the vicinity of an end portion of a conventional fine carbon fiber; FIG. 2 is a schematic vertical cross-sectional diagram showing a structure in the vicinity of an end portion of another conventional fine carbon fiber; FIG. 3 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 4 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 5 is a schematic side view seen from a direction of an end portion of the fiber according to FIG. 4; FIG. 6 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 7 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 8 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 9 is a schematic vertical cross-sectional diagram for explaining structures in the vicinities of both end portions of a fine carbon fiber to be used in the present invention; FIG. 10 is a schematic vertical cross-sectional diagram for explaining structures in the vicinities of both end portions of a fine carbon fiber to be used in the present invention; FIG. 11 is a transmission electron micrograph of the catalyst carrier according to Example 1; FIG. 12 is a transmission electron micrograph of the catalyst carrier according to Example 2; FIG. 13 is a transmission electron micrograph of the catalyst carrier according to Example 3; FIG. 14 is a transmission electron micrograph of the catalyst carrier according to Example 4; FIG. 15 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 1; FIG. 16 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 2; FIG. 17 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 3; and FIG. 18 is a graph showing Tafel plots of fuel batteries using catalyst carriers according to Examples 1 to 4 and Comparative Examples 1 to 3. MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. A vapor-grown carbon fiber to be used as a carrier of a catalyst carrier of the present invention has an average outer diameter of from 2 to 500 nm and has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 to 500 m2/g and an aspect ratio of from 1 to 200. Preferably, the average outer diameter is from 15 to 200 nm; the BET specific surface area is from 10 to 200 m2/g; and the aspect ratio is from 2 to 150. Further, preferably, an average fiber length is from 2 to 100 μm. By using as a carrier the vapor-grown carbon fiber which has been subjected to the crushing treatment so as to have properties within the respective ranges as described above, when a catalyst metal is carried thereon, the carrier is capable of carrying the catalyst metal while being in a state of particles having a small diameter and a large specific surface area and, as a result, a catalytic activity can be enhanced. The crushing treatment has preferably been performed such that an average fiber length after the treatment becomes 0.8 or less when the average fiber length before the treatment is taken as 1. Further, the crushing treatment has preferably been performed such that a BET specific surface area after the treatment becomes 1.1 or more and, more preferably, 1.4 or more, when the BET specific surface area before the treatment is taken as 1. The vapor-grown carbon fiber to be used in the present invention preferably contains a branched carbon fiber, and thereby an electric conductive pass of the carbon fiber is formed and, accordingly, electric conductivity as the catalyst carrier can be enhanced. The vapor-grown carbon fiber to be used in the present invention is prepared by subjecting a fine carbon fiber produced by a vapor phase method to a crushing treatment. Performing the crushing treatment enables to produce a fine carbon fiber having a multi-layer structure, which comprises a discontinuous surface of a graphene sheet having a fracture surface at an end portion of the fiber; a continuous surface formed by combining an end portion of at least one graphene sheet with an end portion of an adjacent graphene sheet; and a hollow space in a center axis. By such a structure as described above, electric resistance of the carbon fiber is reduced and electric conductivity as a catalyst carrier is enhanced. Characteristics of the fine carbon fiber are described with reference to FIGS. 1 to 10. In these figures, graphene sheets (layers of graphite or crystals similar to graphite) are schematically shown in solid lines. As shown in a schematic vertical cross-sectional diagram according to FIG. 1 or 2, the fine carbon fiber comprises a discontinuous surface (1) of a graphene sheet having a fracture surface or a closed surface (2) having a continuous surface of the graphene sheets at the end portion of a fiber, and a hollow space (3). On the other hand, as shown in a schematic cross-sectional diagram according to FIG. 3 or 4, a preferred mode of the fine carbon fiber according to the invention is such a fine carbon fiber having a hollow space (3) produced by a vapor phase method, which comprises a discontinuous surface (1) of a graphene sheet having a fracture surface at an end portion of the fiber and a continuous surface (2) formed by combining an end portion of at least one graphene sheet and an end portion of an adjacent graphene sheet. The fracture surface denotes a plane generated by crushing or the like. Continuity of the graphene sheets is broken at the fracture surface, to thereby allow an edge carbon atom at a fracture portion inside a basal surface, an edge carbon atom at a border portion of a crystallite or the like to appear. The fracture surface is, for example, an end surface at approximately right angles to a center axis of the carbon fiber. Even in the fiber having a low aspect ratio (1 to 200), the hollow space and a multi-layer structure (growth ring structure) are maintained. The carbon fiber according to FIG. 3 has a closed surface (2) having two continuous surfaces of the graphene sheets; in one portion (a), two adjacent graphene sheets are combined with each other at respective end portions, while, in the other portion (b), among adjacent four graphene sheets, outermost two graphene sheets are combined with each other at end portions, while inner two graphene sheets are combined with each other at end portions, respectively. The discontinuous surface (1) of the graphene sheet is present at the side of a hollow space (3) adjacent to the portion (a). The carbon fiber according to FIG. 4 is a carbon fiber comprising four layers (4, 6, 8, 10) of graphene sheets; outer two layers of the graphene sheets (4, 6) form continuous surfaces (2(a)) in which end portions thereof are combined with each other all over the circumference, while inner two layers of the graphene sheets (8, 10) simultaneously form a closed portion (2(b)) having a continuous surface in which end portions thereof are combined with each other and a portion (1(a)) in which end portions thereof have a discontinuous surface. FIG. 5 is a schematic side view of the carbon fiber having the structure according to FIG. 4 seen from a direction of the end portion thereof. White portions show continuous surfaces (2(a), 2(b)), while a black portion shows a discontinuous surface (1(a)). A center portion is a hollow portion, while a grey portion shows an interface between graphene sheets (6) and (8). A continuous surface of the graphene sheets which is present at an end of the fine carbon fiber is continuous also in the direction of the circumference; however, it is considered that the discontinuity may be generated also in the direction of the circumference by an influence of a defect caused by crushing, a thermal treatment temperature, an impurity component other than carbon, etc. Each of FIGS. 6 to 8 shows a carbon fiber comprising eight layers of the graphene sheets. In FIG. 6, outer two layers of the graphene sheets (12, 14) form a continuous surface in which end portions thereof are combined with each other all over the circumference, while each of the other six layers of the graphene sheets form a discontinuous surface. In FIG. 7, an outermost layer of the graphene sheet (16) and the fourth from the outermost layer of the graphene sheet (22), and the second and the third layers from the outermost layer of the graphene sheet (18, 20) which are adjacent to each other are combined with each other respectively at the end portions to form continuous surfaces all over the circumference, while each of the other four layers of the graphene sheets form a discontinuous surface. In FIG. 8, an outermost layer of the graphene sheet (24) and the sixth layer from the outermost layer of the graphene sheet (34), the second and fifth layers from the outermost layer of the graphene sheet (26, 32), and the third and fourth layers from the outermost layer of the graphene sheet (28, 30) which are adjacent to each other are combined with each other respectively at the end portions to form continuous surfaces all over the circumference, while each of the other two layers of the graphene sheets form a discontinuous surface. Each of FIGS. 9 and 10 shows an entire picture of a fine carbon fiber. FIG. 9 shows a mode in which one end of the fiber forms only continuous surfaces in the same manner as conventional and the other end has both continuous and discontinuous surfaces, while FIG. 10 shows a mode in which both ends of the fiber have both continuous and discontinuous surfaces. The continuous surface which exists in the same surface as the fracture surface shows a surface in which a defect is generated in the graphene sheet laminated by thermal chemical vapor deposition and, accordingly, the graphene sheet has lost the regularity and is combined with an adjacent graphene sheet; or a fracture end of a graphene sheet is recombined with an end of another graphene sheet by a high temperature treatment of 2000° C. or more. A curved portion of the continuous surface comprises one or more of graphene sheets; however, in a case in which the number of the laminated graphene sheets is small, namely, in a case in which a curvature radius of such curved graphene sheets is small, the fiber is hard to stably exist since a surface energy of the curved portion is large, and therefore, the number of the laminated graphene sheets at the curved portion is preferably three more, more preferably five or more and, particularly preferably, five to ten. The vapor-grown carbon fiber used in the present invention can be produced by crushing a vapor-grown carbon fiber produced by a vapor phase method and, preferably, a carbon fiber comprising a branched carbon fiber (produced by a method as described in, for example, JP-A-2002-266170 (WO02/49412)). The vapor-grown carbon fiber to be used in such production can ordinarily be obtained by thermally decomposing an organic compound while using an organic transition metal compound as a catalyst. The organic compound which can serve as a raw material for the carbon fiber is a compound selected from among toluene, benzene, naphthalene, gases such as ethylene, acetylene, ethane, a natural gas, carbon monoxide and the like and mixtures thereof. Thereamong, aromatic hydrocarbons such as toluene and benzene are preferred. The organic transition metal compound is an organic compound containing a transition metal which can be a catalyst, specifically, any one of metals belonging to the groups IV to X in the periodic table. Particularly, compounds such as ferrocene and nickelocene are preferred. The carbon fiber is, preferably, a carbon fiber in which an interlayer distance (d002) of a hexagonal carbon layer (002) by an X-ray diffractometry is 0.345 nm or more, a ratio (Id/Ig) of a peak height (Id) of the band at 1341 to 1349 cm−1 to a peak height (Ig) of the band at 1570 to 1578 cm−1 in a Raman scattering spectrum is 1 or more. In this case, Id denotes a broad band region corresponding to an increase of irregularity of a carbon structure, while Ig denotes a relatively sharp band region associated with a perfect graphite structure. Raw materials to be crushed can be subjected to a thermal treatment at 600 to 1300° C. in order to remove an organic substance such as tar attached on a surface of the carbon fiber obtained by thermal decomposition. As for crushing methods, a rotary crusher, a high-speed mill, a ball mill, a medium stirring mill, which adopts a method of crushing the fiber using an impact force, a jet crusher and the like can be utilized. Particularly, a vibrating mill such as a circular vibrating mill, a gyratory vibrating mill or a centrifugal mill is preferred. As for crushing media, ceramics balls of alumina, zirconia, silicon nitride and the like, or metal balls of stainless steel and the like can be used. Among these, stainless steel balls which can be removed by a high-temperature thermal treatment are preferred. Further, it is advantageous to perform a dry type crushing in the absence of water and/or an organic solvent, since it is not necessary to perform a post-treatment step such as removing a dispersant after the crushing, drying the solvent or crushing a dry coagulated fiber. The crushing is preferably performed in an atmosphere having an oxygen concentration of 5% by volume or more. By allowing oxygen to be present in a volume of 5% or more, a surface of a crushed carbon fiber is modified, to thereby facilitate a catalyst metal to be carried. The crushing is preferably performed in the air. Further, in a pretreatment or a post-treatment of the crushing, a graphitization treatment can be performed for the purpose of enhancing electric conductivity of the vapor-grown carbon fiber. The graphitization treatment can be performed by carrying out a thermal treatment at 2000 to 3000° C. in an atmosphere of an inert gas. The catalyst carrier according to the present invention comprises a crushed vapor-grown carbon fiber and a catalyst metal for promoting an oxidation-reduction reaction carried on the carbon fiber. Catalyst metals for promoting the oxidation-reduction reaction are at least one element selected from the group consisting of transition metals belonging to the groups IV and V in the periodic table comprising platinum and other platinum metal elements or mixtures thereof, preferably, platinum metal elements (nickel, palladium and platinum) or an alloy containing these metal elements. A method for carrying the catalyst metal on the crushed vapor-grown carbon fiber is not particularly limited and is performed by, for example, a liquid phase reduction method. An example in which fine platinum particles are carried on the crushed vapor-grown carbon fiber by the liquid reduction method is described below. Firstly, the crushed carbon fiber is dispersed in a distiled water and a pH value of the resultant dispersion is adjusted by using, for example, sodium carbonate. A dispersion operation can be performed by, for example, an ultrasonic wave treatment while confirming a dispersion condition by, for example, visual observation. Since the vapor-grown carbon fiber is high in hydrophobicity, it is preferable to enhance hydrophilicity by performing a surface treatment (hereinafter, referred to also as “hydrophilization treatment”) on the carbon fiber in advance and, by this treatment, a specific surface area of the catalyst metal to be carried can be improved. The surface treatment can be performed in, for example, an acid solution (such as an aqueous nitric acid solution) for one to ten hours at 60 to 90° C. To the resultant carbon fiber dispersion, an aqueous solution of chloroplatinic acid is added, thoroughly stirred and, then, an excess amount of a reducing agent such as formaldehyde is added to allow a reaction to proceed and, thereafter, a solid article is recovered by filtration. By drying the thus-recovered solid article in an atmosphere of an inert gas such as argon at 120 to 500° C., a catalyst carrier can be obtained in which platinum fine particles are carried on the vapor-grown carbon fiber. The catalyst carrier according to the present invention is a catalyst carrier in which fine catalyst metal particles are carried on a vapor-grown carbon fiber as a carrier and has an improved catalyst activity per unit amount of the catalyst metal compared with a case in which a carrier in powder form such as carbon black is used. Further, by using the vapor-grown carbon fiber subjected to a crushing treatment, a grain diameter of the catalyst metal particles to be carried comes to be apparently small compared with a case in which the crushing treatment is not performed (namely, the specific surface area of the catalyst metal comes to be large). Specifically, it is possible to allow an average grain diameter of the catalyst metal to be carried to be 15 nm or less and, further, 10 nm or less, which enables to enhance the catalyst activity of the catalyst support and to obtain favorable characteristics for use in the electrode catalyst for the fuel battery. The catalyst carrier according to the present invention can be applied for an electrode material, a membrane electrode assembly for a fuel battery, a cell for a fuel battery and a fuel battery and these articles can be produced by a known method. The electrode material according to the present invention can be produced by forming a catalyst layer containing the above-described catalyst carrier on an electrically conductive base material such as carbon paper, carbon fiber woven fabric or carbon non-woven fabric. Formation of the catalyst layer can be performed by, for example, applying a slurry containing the catalyst carrier on an electrically conductive base material and, then, drying the resultant base material. The membrane electrode assembly for the fuel battery according to the present invention can be produced by thermally press-adhering the above-described electrode material comprising a gas diffusion layer and a catalyst layer on both surfaces of an electrolyte membrane. In a case in which the fuel battery is of a solid polymer type, the electrolyte membrane comprises a polymer material and, for example, a perfluorosulfonic acid type polymer can be used. A fuel battery cell can be prepared by sandwiching the membrane electrode assembly by separators having electric conductivity and two or more layers of such cell units are laminated one on another, to thereby prepare a fuel battery stack having a high output. Further, in order to suppress a leakage of an inner gas, it is also possible to provide a gasket between the electrolyte material and each of the separators. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will specifically be described with reference to representative examples; however, these examples are given for an illustrative purpose only and by no means limit the invention. Further, a ratio of an average fiber length was determined by obtaining average fiber lengths before and after carbon fibers were subjected to a crushing treatment in a cross-sectional photograph of carbon fibers by a transmission electron microscope (TEM). Further, a specific surface area was measured in accordance with a BET method which is an ordinary measuring method of the specific surface area by using a specific surface area measuring apparatus “NOVA-1200” manufactured by Yuasa-Ionics Co., Ltd. EXAMPLE 1 5 g of vapor-grown carbon fiber having an average outer diameter of 150 nm, a specific surface area of 13 m2/g and an average fiber length of 10 μm was loaded in a rotary crusher (stainless steel-made crushing blade, rotation rate: 25000 rpm) and subjected to a crushing treatment for 10 minutes. Thereafter, a specific surface area and an average fiber length of the carbon fiber were measured and, as a result, the specific surface area and the average fiber length were 18 m2/g and 7.5 μm, respectively, which were 1.6 times and 0.75 times the original values, respectively. 0.2 g of the thus-crushed vapor-grown carbon fiber was dispersed in 50 ml of distilled water, 0.172 g of sodium carbonate was added and then, stirred with heat at 80° C. To the resultant dispersion, an aqueous solution containing 0.135 g of chloroplatinic acid was added dropwise, stirred for two hours and, then, a 35% aqueous solution of formaldehyde was added dropwise. After stirred for one hour, the resultant solution was filtered and, then, a solid material was subjected to a drying treatment for two hours at 400° C. in an atmosphere of argon, to thereby obtain a catalyst carrier in which a platinum grain was carried on a carbon fiber. A transmission electron microscope (TEM) photograph thereof is shown in FIG. 11. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 8 nm. EXAMPLE 2 5 g of vapor-grown carbon fiber having an average outer diameter of 150 nm, a specific surface area of 13 m2/g and an average fiber length of 10 μm was loaded in a rotary crusher (stainless steel-made crushing blade, rotation rate: 25000 rpm) and subjected to a crushing treatment for 20 minutes. Thereafter, a specific surface area and an average fiber length of the carbon fiber were measured and, as a result, the specific surface area and the average fiber length were 24 m2/g and 6.0 μm, respectively, which were 1.8 times and 0.6 times the original values, respectively. 0.2 g of the thus-crushed vapor-grown carbon fiber was dispersed in 50 ml of distilled water, 0.172 g of sodium carbonate was added and then, stirred with heat at 80° C. To the resultant dispersion, an aqueous solution containing 0.135 g of chloroplatinic acid was added dropwise, stirred for two hours and then, a 35% aqueous solution of formaldehyde was added dropwise. After stirred for one hour, the resultant solution was filtered and, then, a solid material was subjected to a drying treatment for two hours at 400° C. in an atmosphere of argon, to thereby obtain a catalyst carrier in which platinum particles were carried on a carbon fiber. A TEM photograph thereof is shown in FIG. 12. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 5 nm. EXAMPLE 3 5 g of vapor-grown carbon fiber having an average outer diameter of 150 nm, a specific surface area of 13 m2/g and an average fiber length of 10 μm was loaded in a rotary crusher (stainless steel-made crushing blade, rotation rate: 25000 rpm) and subjected to a crushing treatment for 10 minutes. Thereafter, a specific surface area and an average fiber length of the carbon fiber were measured and, as a result, the specific surface area and the average fiber length were 18 m2/g and 7.5 μm, respectively, which were 1.6 times and 0.75 times the original values, respectively. 0.2 g of the thus-crushed vapor-grown carbon fiber was, after being heated in a 60% aqueous solution of nitric acid for five hours at 70° C., dispersed in 50 ml of distilled water, 0.172 g of sodium carbonate was added and the dispersion was stirred with heat at 80° C. To the resultant dispersion an aqueous solution containing 0.135 g of chloroplatinic acid was added dropwise, stirred for two hours and then, a 35% aqueous solution of formaldehyde was added dropwise. After stirred for one hour, the resultant solution was filtered and, then, a solid material was subjected to a drying treatment for two hours at 400° C. in an atmosphere of argon, to thereby obtain a catalyst carrier in which platinum particles were carried on a carbon fiber. A TEM photograph thereof is shown in FIG. 13. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 6 nm. EXAMPLE 4 5 g of vapor-grown carbon fiber having an average outer diameter of 150 nm, a specific surface area of 13 m2/g and an average fiber length of 10 μm was loaded in a rotary crusher (stainless steel-made crushing blade, rotation rate: 25000 rpm) and subjected to a crushing treatment for 20 minutes. Thereafter, a specific surface area and an average fiber length of the carbon fiber were measured and, as a result, the specific surface area and the average fiber length were 24 m2/g and 6.0 μm, respectively, which were 1.8 times and 0.6 times the original values, respectively. 0.2 g of the thus-crushed vapor-grown carbon fiber was, after being heated in a 60% aqueous solution of nitric acid for five hours at 70° C., dispersed in 50 ml of distilled water, 0.172 g of sodium carbonate was added and the dispersion was stirred with heat at 80° C. To the resultant dispersion an aqueous solution containing 0.135 g of chloroplatinic acid was added dropwise, stirred for two hours and then, a 35% aqueous solution of formaldehyde was added dropwise. After stirred for one hour, the resultant solution was filtered and, then, a solid material was subjected to a drying treatment for two hours at 400° C. in an atmosphere of argon, to thereby obtain a catalyst carrier in which platinum particles were carried on a carbon fiber. A TEM photograph thereof is shown in FIG. 14. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 3 nm. COMPARATIVE EXAMPLE 1 Same operations were performed as in Example 1 except that the crushing treatment was not performed, to thereby obtain a catalyst carrier in which platinum particles were carried on the carbon fiber. A TEM photograph thereof is shown in FIG. 15. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 19 nm. COMPARATIVE EXAMPLE 2 Same operations were performed as in Example 3 except that the crushing treatment was not performed, to thereby obtain a catalyst carrier in which platinum particles were carried on the carbon fiber. A TEM photograph thereof is shown in FIG. 16. Further, diameters of platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 23 nm. COMPARATIVE EXAMPLE 3 Carbon black available in the market (under the name of Vulcan XC-72R manufactured by Cabot Inc. having a specific surface area of 230 m2/g) was used as it was. 0.2 g thereof was, after being heated for five hours at 70° C. in a 60% aqueous solution of nitric acid, dispersed in 50 ml of distilled water, sodium carbonate was added and the dispersion was stirred with heat at 80° C. An aqueous solution containing 0.135 g of chloroplatinic acid was added dropwise thereto, and the resultant dispersion was stirred for two hours and then, a 35% aqueous solution of formaldehyde was added dropwise. After stirred for one hour, the resultant solution was filtered and then, a solid material was subjected to a drying treatment for two hours at 400° C. in an atmosphere of argon, to thereby obtain a catalyst carrier in which platinum particles were carried on carbon black. A TEM photograph thereof is shown in FIG. 17. Further, diameters of the platinum catalyst were measured by observing the TEM photograph, to thereby obtain a distribution of the diameters. As a result, an average diameter of the platinum catalyst particles was 2 nm. TABLE 1 Treating conditions and powder characteristics Average Specific diameter of Time Surface Hydrophilization platinum (min.) Area (m2/g) treatment particles (nm) Example 1 10 18 Not 8 performed Example 2 20 24 Not 5 performed Example 3 10 18 Performed 6 Example 4 20 24 Performed 3 Comparative 13 Not 19 Example 1 performed Comparative 13 Performed 23 Example 2 Comparative 230 Performed 2 Example 3 EXPERIMENT EXAMPLE Electrochemical measurement Each of the catalyst carriers prepared according to Examples 1 to 4 and Comparative Examples 1 to 3 was mixed with a NAFION solution and the resultant mixture was applied on a carbon electrode, and an electrochemical measurement was performed by using the resultant electrode. Activity per unit amount of a catalyst metal was evaluated from Tafel plots determined by an absolute value of a current density, a logarithmic number of the current density and a potential at a given voltage measured by a slow scan voltamogram (SSV). A 3-electrode type battery was used in an experiment, wherein a glassy carbon electrode was used as a working electrode, a platinum electrode as a counter electrode, and a hydrogen electrode as a reference electrode. As for a measurement condition, a current value was measured while a voltage was changed from 1.2 V to 0.4 V at a scanning rate of 1 mV/sec. In order to standardize the thus-measured current values to be a current density (mA/cm2), a surface area of the electrode was obtained by using a cyclic voltammetry. The measurement of the surface area of the electrode was conducted with reference to a method as described in Denkikagaku Sokuteiho (Electrochemical Measuring Method) (Vol. I), Gihodo Shuppan Co., Ltd., p 88. Results are shown in Table 2. The order of the absolute values of the current density at a voltage of 0.5 V in Examples was as follows: Example 2>Example 1>Example 3=Example 4>Comparative Example 1=Comparative Example 2>>Comparative Example 3. Further, Tafel plots determined by a logarithmic number of current density at a voltage of from 0.82 V to 0.94 V and the voltage are shown in FIG. 18. As is apparent from FIG. 18, it is found that, when any one of the catalysts in Examples 1 to 4 was used in such a voltage range as described above, a higher current density was able to be obtained compared with a case in which any one of the catalysts in Comparative Examples was used and, accordingly, a catalyst performance has been enhanced. TABLE 2 Current density (mA/cm2) by SSV measurement −0.7 V −0.6 V −0.5 V Example 1 −0.2 −0.3 −0.4 Example 2 −0.3 −0.4 −0.5 Example 3 −0.2 −0.2 −0.3 Example 4 −0.2 −0.2 −0.3 Comparative −0.15 −0.2 −0.2 Example 1 Comparative −0.15 −0.2 −0.2 Example 2 Comparative −0.05 −0.06 −0.06 Example 3 | <SOH> BACKGROUND ART <EOH>A solid polymer type fuel battery is attracting attention to be used for a cell automobile and a portable power supply since it is compact and can obtain a high current density when operated at room temperature compared with a phosphoric-acid type fuel battery and a molten carbonate type fuel battery. Further, many proposals on components, system compositions and the like in such fields have been made. A stack structure of a conventional solid polymer type fuel battery is a sandwich structure of, for example, of separator/electrode (oxygen electrode)/electrolyte membrane/electrode (hydrogen electrode)/separator. Required characteristics of an electrode for this fuel battery are to prevent the electrode from poisoning by carbon monoxide and to enhance activity per unit amount of a catalyst metal. For the purpose of preventing such poisoning and enhancing the activity, many trials have been made to date on metals or alloys thereof to be used as catalysts as described in JP-A-2001-85020 (U.S. Pat. No. 6,689,505), which describes that a particle size of a catalyst is preferably several nm. On the other hand, as for carbon to be used for a carrier, particulate carbon such as ordinary carbon black is used as described in JP-A-8-117598, JP-A-2003-201417 (EP 1309024) and JP-A-2001-357857. However, since the contact between carbon particles is conducted by a point contact, there is a problem that resistance is large and gas permeability is insufficient. In order to solve these problems, it has been considered effective to change the particulate carbon to fiber carbon to be used for the carrier as described in JP-A-7-262997, JP-A-2003-317742 and JP-A-2003-200052. As for carbon fibers, a vapor-grown carbon fiber, a carbon nanotube and a PAN type carbon fiber are known. However, in any of reports which have been made public to date, a technique to produce an electrode comprising a carbon fiber on which fine catalyst particles are uniformly carried with a high density has not been described. | <SOH> BRIEF DESCRIPTION OF THE DRWAINGS <EOH>FIG. 1 is a schematic vertical cross-sectional diagram showing a structure in the vicinity of an end portion of a conventional fine carbon fiber; FIG. 2 is a schematic vertical cross-sectional diagram showing a structure in the vicinity of an end portion of another conventional fine carbon fiber; FIG. 3 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 4 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 5 is a schematic side view seen from a direction of an end portion of the fiber according to FIG. 4 ; FIG. 6 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 7 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 8 is a schematic vertical cross-sectional diagram for explaining a structure in the vicinity of an end portion of a fine carbon fiber to be used in the present invention; FIG. 9 is a schematic vertical cross-sectional diagram for explaining structures in the vicinities of both end portions of a fine carbon fiber to be used in the present invention; FIG. 10 is a schematic vertical cross-sectional diagram for explaining structures in the vicinities of both end portions of a fine carbon fiber to be used in the present invention; FIG. 11 is a transmission electron micrograph of the catalyst carrier according to Example 1; FIG. 12 is a transmission electron micrograph of the catalyst carrier according to Example 2; FIG. 13 is a transmission electron micrograph of the catalyst carrier according to Example 3; FIG. 14 is a transmission electron micrograph of the catalyst carrier according to Example 4; FIG. 15 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 1; FIG. 16 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 2; FIG. 17 is a transmission electron micrograph of the catalyst carrier according to Comparative Example 3; and FIG. 18 is a graph showing Tafel plots of fuel batteries using catalyst carriers according to Examples 1 to 4 and Comparative Examples 1 to 3. detailed-description description="Detailed Description" end="lead"? | 20050126 | 20100706 | 20051103 | 62519.0 | 0 | HAILEY, PATRICIA L | CATALYST CARRIER AND FUEL CELL USING THE SAME | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,041,984 | ACCEPTED | Fuel feed apparatus having opening in sub-tank | A fuel feed apparatus includes a sub-tank and a fuel pump that are received in the fuel tank. The sub-tank has an inner space that is partitioned into at least a first chamber and a second chamber. The fuel pump is arranged in the first chamber to discharge fuel received in the sub-tank to the outside of the fuel tank. The second chamber has an opening, through which the second chamber communicates with the outside of the sub-tank such that fuel accumulated in the second chamber is exhausted to the outside of the sub-tank through the opening. The fuel tank has a first tank space and a second tank space. The sub-tank is received in the first tank space. A first jet pump is disposed in the second chamber of the sub-tank. The first jet pump draws fuel accumulated in the second tank space into the first tank space. | 1. A fuel feed apparatus that is at least partially received in a fuel tank, the fuel feed apparatus comprising: a sub-tank that is received in the fuel tank, the sub-tank has an inner space that is partitioned into at least a first chamber and a second chamber; and a fuel pump that is arranged in the first chamber, the fuel pump discharging fuel, which is received in the sub-tank, to an outside of the fuel tank, wherein the second chamber defines an opening through which the second chamber communicates with an outside of the sub-tank such that fuel accumulated in the second chamber is capable of being exhausted to the outside of the sub-tank through the opening. 2. The fuel feed apparatus according to claim 1, wherein the fuel tank includes a first tank space and a second tank space, and the sub-tank is received in the first tank space of the fuel tank, the fuel feed apparatus further comprising: a first jet pump that is received in the second chamber of the sub-tank, wherein the first jet pump is capable of drawing fuel accumulated in the second tank space of the fuel tank into the first tank space of the fuel tank. 3. The fuel feed apparatus according to claim 1, the fuel feed apparatus further comprising: a second jet pump that draws fuel received in the outside of the sub-tank into the sub-tank, wherein the opening has an opening area such that an amount of fuel, which is exhausted from the second chamber through the opening, is less than an amount of fuel, which is drawn from the second jet pump into the sub-tank. 4. The fuel feed apparatus according to claim 1, wherein the opening is defined in a bottom portion of the sub-tank. 5. The fuel feed apparatus according to claim 4, wherein the opening extends through the bottom portion of the sub-tank in a substantially axial direction of the sub-tank. | CROSS REFERENCE TO RELATED APPLICATIONS This application is based on and incorporates herein by reference Japanese Patent Application No. 2004-23656 filed on Jan. 30, 2004. FIELD OF THE INVENTION The present invention relates to a fuel feed apparatus that feeds fuel received in a fuel tank to the outside of the fuel tank. BACKGROUND OF THE INVENTION A fuel feed apparatus disclosed in JP-A-9-268957 is capable of stably feeding fuel from an inside of a fuel tank to the outside, even when an amount of fuel received in the fuel tank decreases. The fuel feed apparatus includes a sub-tank that is received in the fuel tank. The inner space of the sub-tank needs to be partitioned into multiple chambers to individually receive components in the fuel feed apparatus having a specific structure. A fuel pump may be arranged in one of the separated chambers. In this structure, fuel can be circulated in the chamber receiving the fuel pump. However, fuel may remain in another chamber, in which the fuel pump is not provided, and the remaining fuel may be deteriorated due to oxidization. As a result, components of the fuel feed apparatus such as the sub-tank may be corroded due to the deteriorated fuel, and proper operation of components may not be maintained. SUMMARY OF THE INVENTION In view of the foregoing problems, it is an object of the present invention to produce a fuel feed apparatus that is capable of reducing fuel remaining in a sub-tank. According to the present invention, a fuel feed apparatus, which is at least partially received in a fuel tank, includes a sub-tank and a fuel pump. The sub-tank is received in the fuel tank. The sub-tank has an inner space that is partitioned into at least a first chamber and a second chamber. The fuel pump is arranged in the first chamber. The fuel pump discharges fuel, which is received in the sub-tank, to the outside of the fuel tank. The second chamber defines an opening, through which the second chamber communicates with the outside of the sub-tank such that fuel accumulated in the second chamber is capable of being exhausted to the outside of the sub-tank through the opening. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings: FIG. 1 is a side view showing a fuel feed apparatus according to a first embodiment of the present invention; FIG. 2 is a top view showing the fuel feed apparatus according to the first embodiment; FIG. 3 is a top view showing a sub-tank of the fuel feed apparatus according to the first embodiment; FIG. 4 is a bottom view showing the fuel feed apparatus when being viewed from the side of arrow IV in FIG. 1 according to the first embodiment; FIG. 5 is a cross-sectional side view taken along the line V-V in FIG. 3 according to the first embodiment; and FIG. 6 is a cross-sectional side view showing a fuel tank receiving the fuel feed apparatus according to the first embodiment. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS First Embodiment As shown in FIG. 1, a fuel feed apparatus 10 has a circular-shaped lid member 11 that covers an opening formed in an upper wall portion of a fuel tank 100. As shown in FIG. 6, the fuel tank 100, which receives the fuel feed apparatus 10, is integrally formed of resin to be in a saddleback shape, and is mounted in a vehicle over a drive shaft 200. The fuel tank 100 includes a first tank space 100a and a second tank space 100b that are communicated with each other through a connecting portion 100c, which is arranged to pass over the drive shaft 200. The fuel feed apparatus 10 is received in the first tank space 100a of the fuel tank 100. As shown in FIGS. 1, 2, the fuel feed apparatus 10 includes the lid member 11 and a sub-tank 20. The fuel feed apparatus 10 further includes a first shaft 21 and a second shaft 22 that support the lid member 11 and the sub-tank 20 such that the lid member 11 and the sub-tank 20 are axially movable relative to each other. Most of the fuel feed apparatus 10 is received in the fuel tank 100 excluding the lid member 11. The lid member 11 has a discharge pipe 12 and an electric connector 13. Fuel is discharged from a fuel pump 41 (FIG. 2) received in the sub-tank 20, and the fuel flows to the outside of the fuel tank 100 through the discharge pipe 12. The electric connector 13 is electrically connected with a power source (not shown) via a lead wire 14 to supply the fuel pump 41 received in the sub-tank 20 with electric power. The first and second shafts 21, 22 (FIG. 1) are respectively press-inserted into press-insertion portions 15 provided to the lid member 11 on one axially end portions. The first and second shafts 21, 22 are respectively supported by a first supporting portion 23 and a second supporting portion 24 (FIGS. 2, 3), which are provided to the sub-tank 20, on the other axially end portions. The first and second shafts 21, 22 are made of a metallic material, such as stainless steel or aluminum, or a nonmetallic material such as resin. Referring back to FIG. 1, a spring 25 is provided to the outer circumferential periphery of the first shaft 21 as a biasing means. The spring 25 contacts with one of the press-insertion portions 15 of the lid member 11 on one axial end side of the spring 25. The spring 25 contacts with the sub-tank 20 on the other axial end side of the spring 25. The spring 25 axially resiliently extends such that the lid member 11 and the sub-tank 20 are axially apart from each other. Thus, the sub-tank 20 is pressed onto the inner bottom face of the fuel tank 100 by resilience of the spring 25, even when the fuel tank 100 expands or contracts due to a variation in pressure caused by a variation in temperature and a variation in amount of fuel. As shown in FIG. 2, the sub-tank 20 receives the fuel pump 41, a fuel filter 42, a suction filter, a pressure regulator (none shown), a first jet pump 60 and a second jet pump 70 (FIG. 1). The suction filter filters relatively large debris contained in fuel that is drawn from the inside of the sub-tank 20 by the fuel pump 41. The pressure regulator controls pressure of fuel discharged from the fuel pump 41 at a predetermined pressure. The fuel filter (FIG. 2) filters relatively small debris contained in fuel discharged by the fuel pump 41. The fuel pump 41 is received in the sub-tank 20 such that the suction side of the fuel pump 41 is arranged on the lower side in FIG. 1, and the discharge side of the fuel pump 41 is arranged on the upper side in FIG. 1. The fuel pump 41 includes a motor (not shown) to generate suction force using a rotating member (not shown) that integrally rotates with the motor. The sub-tank 20 is formed in a bottomed cylindrical shape that includes a circumferential wall portion 31, which is formed in a substantially cylindrical shape, and a bottom portion 32. The bottom portion 32 is arranged on the axially end side of the circumferential wall portion 31 on the axially opposite side as the lid member 11. The sub-tank 20 includes a partition wall 33 that partitions the inner space of the sub-tank 20 defined by the circumferential wall portion 31 and the bottom portion 32. The partition wall 33 forms a shortcut that substantially linearly connects two points of the inner circumferential periphery of the substantially cylindrical circumferential wall portion 31. That is, the partition wall 33 becomes a chord subtending an arc of the inner circumferential periphery of the circumferential wall portion 31. The partition wall 33 connects with the bottom portion 32 on the axially opposite end side as the lid member 11. Thus, the inner space of the sub-tank 20 is partitioned by the partition wall 33 into a main chamber (first chamber) 34 and a sub-chamber (second chamber) 35 as shown in FIG. 2. The main chamber 34 receives the fuel pump 41, the fuel filter 42, the suction filter, the pressure regulator, and the like. The sub-chamber 35 receives the first jet pump 60, and the like. The first jet pump 60 jets fuel discharged from the fuel pump 41 to generate suction force for drawing fuel received in the second tank space 100b of the fuel tank 100 through a filter 62 and a passage pipe 61 (FIG. 6). Fuel is drawn from the second tank space 100b by the first jet pump 60, and the fuel is supplied into the sub-chamber 35 (FIG. 2), so that the fuel is accumulated in the sub-chamber 35. The height of the partition wall 33, which partitions the inner space of the sub-tank 20 into the main chamber 34 and the sub-chamber 35, is less than the height of the circumferential wall portion 31 in the vertical direction in FIG. 1. Specifically, the end portion of the partition wall 33 on the side of the lid member 11 is located on the side of the bottom portion 32, i.e., lower side compared with the end portion of the circumferential wall portion 31 on the side of the lid member 11. Fuel is drawn into the sub-chamber 35 by the first jet pump 60, and the fuel is accumulated in the sub-chamber 35. When liquid level of the fuel accumulated in the sub-chamber 35 exceeds the height of the partition wall 33, the fuel flows over the partition wall 33 into the main chamber 34. Thus, fuel overflows from the sub-chamber 35 into the main chamber 34 of the sub-tank 20 over the partition wall 33. As shown in FIG. 1, the second jet pump 70 is provided to the outer circumferential periphery of the sub-tank 20. The second jet pump 70 includes a nozzle portion 71 and a throat portion 72. Fuel is pressurized in the fuel pump 41, and the pressurized fuel is partially supplied into the nozzle portion 71 through a fuel passage 73. The throat portion 72 communicates with the main chamber 34 (FIG. 2) of the sub-tank 20. Fuel is supplied from the fuel pump 41 into the nozzle portion 71, and the fuel is jetted from the nozzle portion 71 into the throat portion 72, so that suction pressure is generated in the throat portion 72, and fuel is drawn into the throat portion 72. Thus, fuel received in the outside of the sub-tank 20, i.e., fuel received in the first tank space 100a of the fuel tank 100 is drawn into the sub-tank 20 through the throat portion 72. Fuel is constantly supplied into the main chamber 34 of the sub-tank 20, in which the fuel pump 41 is received, by the first and second jet pumps 60, 70. Therefore, fuel remaining around the sub-tank 20 can be drawn into the sub-tank 20, even when liquid level of fuel decreases in the first tank space 100a of the fuel tank 100. As a result, the inside of the sub-tank 20 can be filled with fuel, regardless of the liquid level in the fuel tank 100. As shown in FIG. 2, the fuel feed apparatus 10 has a sender gauge 50, which serves as a level detecting means, provided to the outer periphery of the circumferential wall portion 31 of the sub-tank 20. The sender gauge 50 includes a detecting device 51, an arm 52 and a float 53. The detecting device 51 is provided to the circumferential wall portion 31 of the sub-tank 20. The arm 52 connects with the detecting device 51 on one end side, and connects with the float 53 on the other end side. The float 53 floats in fuel accumulated in the fuel tank 10. The float 53 vertically moves in the fuel accumulated in the fuel tank 100 in accordance with liquid level of fuel in the fuel tank 100. The arm 52, which connects with the float 53, is capable of rotating around the detecting device 51, such that the arm 52 rotates in accordance with vertical movement of the float 53. The arm 52 and the detecting device 51 are electrically connected with each other, and relative position between the arm 52 and the detecting device 51 can be detected as variation in resistance or the like. The arm 52 rotates in accordance with vertical movement of the float 53, so that liquid level of fuel can be measured by detecting variation in the relative position between the arm 52 and the detecting device 51. Liquid level of fuel is measured using the sender gauge 50, and the measured liquid level is transmitted as an electric signal to an external control device (not shown) via the electric connector 13. As shown in FIGS. 3 to 5, the sub-tank 20 has openings 36, 37 in the sub-chamber 35 on the axially opposite side as the lid member 11, i.e., on the lower side of the sub-tank 20. The openings 36, 37 are through holes that respectively penetrate the bottom portion 32 of the sub-chamber 35 in a substantially axial direction of the sub-tank 20. Thus, the outside of the sub-chamber 35 and the inside of the sub-chamber 35 are communicated with each other through the openings 36, 37. Fuel received in the sub-chamber 35 is exhausted to the lower side in FIG. 1 through the openings 36, 37. Therefore, fuel can be exhausted from the sub-chamber 35 toward the inner bottom wall of the first tank space 100a of the fuel tank 100, which opposes to the bottom portion 32 of the sub-tank 20 in the axial direction of the sub-tank 20. Thus, fuel exhausted from the sub-chamber 35 through the openings 36, 37 can be restricted from interfering with the float 53 of the sender gauge 50 and the like. Total opening area of both the openings 36, 37 is predetermined such that an amount of fuel exhausted from the sub-chamber 35 through the openings 36, 37 becomes less than an amount of fuel supplied from the second jet pump 70 into the sub-tank 20. Here, an amount of fuel supplied from the second jet pump 70 into the sub-tank 20 is defined to be Q1, and an amount of fuel exhausted from the sub-chamber 35 through the openings 36, 37 is defined to be Q2. Here, Q1 is greater than Q2 (Q1>Q2). That is, when the second jet pump 70 is operated, i.e., when the fuel feed apparatus 10 is operated, an amount of fuel supplied into the sub-chamber 35 becomes greater than an amount of fuel exhausted from the sub-chamber 35. Therefore, fuel can be constantly supplied into the sub-tank 20. On the contrary, when the fuel feed apparatus 10 is stopped, the first and second jet pumps 60, 70 are also stopped, so that fuel is not supplied into the sub-chamber 35. Therefore, fuel received in the sub-chamber 35 is drained through the openings 36, 37, and liquid level of fuel decreases in the sub-chamber 35. As a result, fuel received in the sub-chamber 35 can be substantially entirely drained when the fuel feed apparatus 10 is stopped. The sub-chamber 35 of the sub-tank 20 has the openings 36, 37, so that fuel remaining in the sub-chamber 35 can be entirely drained to the outside of the sub-tank 20 through the openings 36, 37, when the fuel feed apparatus 10 is stopped. Therefore, an amount of fuel remaining in the sub-chamber 35 can be reduced, so that fuel can be restricted from deteriorating in the sub-chamber 35. A small amount of fuel may remain in the sub-chamber 35 while the fuel feed apparatus 10 is stopped. Even in this case, fuel received in the sub-chamber 35 can be circulated, when the fuel feed apparatus 10 is restarted, fuel is supplied into the sub-chamber 35, and fuel is exhausted through the openings 36, 37 again. Thus, the first jet pump 60 received in the sub-chamber 35 can be protected from corroding and being damaged due to deteriorated fuel, so that operation of the first jet pump 60 can be maintained. Fuel received in the sub-chamber 35 can be drained through the openings 36, 37, so that fuel can be steadily removed from the sub-chamber 35. The sub-tank 20 has the openings 36, 37 that substantially axially extend through the bottom portion 32 of the sub-chamber 35. Therefore, fuel exhausted from the sub-chamber 35 flows to the opposite side as the lid member 11 in the axial direction of the sub-tank 20, that is, fuel flow can be properly oriented by the openings 36, 37. Accordingly, fuel flowing from the sub-chamber 35 does not interfere with position of the float 53 of the sender gauge 50, even when the sender gauge 50 is provided to the outside of the sub-tank 20. Thus, liquid level of fuel can be precisely detected using the sender gauge 50. Furthermore, total opening area of both the openings 36, 37 is predetermined such that the amount Q2 of fuel exhausted from the sub-chamber 35 through the openings 36, 37 becomes less than the amount Q1 of fuel supplied from the second jet pump 70 into the sub-tank 20. Therefore, fuel can be constantly supplied into the sub-tank 20 when the fuel feed apparatus 10 is operated, and fuel can be steadily drained from the sub-chamber 35 when the fuel feed apparatus 10 is stopped. Other Embodiment The above structure can be applied to a fuel feed apparatus, in which a first jet pump is not received in the sub-chamber 35, for example. Recently, commonality of components is enhanced to reduce manufacturing cost. Therefore, the above fuel feed apparatus 10 including the sub-tank 20 may be applied to a fuel tank that does not have the above saddleback shape including the first and second tank spaces 101a, 101b. In this structure, fuel need not to be communicated between the first and second tank spaces 101a, 101b, and the first jet pump need not to be provided to the fuel feed apparatus. Accordingly, the sub-chamber 35 may be a dead space, in which components are not received. Even in this case, the openings 36, 37 can be formed in the bottom side of the sub-chamber 35, so that fuel flowing into the sub-chamber 35 can be exhausted to the outside through the openings 36, 37. Therefore, fuel can be restricted from remaining in the sub-chamber 35, while components of the fuel feed apparatus 10 are standardized. The sender gauge 50 may be arranged in another position, in which fuel exhausted from the openings 36, 37 does not affect the position of the sender gauge 50. Besides, the fuel feed apparatus may not have the sender gage 50. In these cases, the openings 36, 37 may be formed in the circumferential wall portion 31 of the sub-tank 20, instead of being formed in the bottom portion 32 of the sub-chamber 35. An opening may be formed in the main chamber 34, so that fuel can be restricted from remaining in the main chamber 34. The inside of the inner space of the sub-tank 20 may be partitioned into at least three spaces. In this case, an opening can be formed in at least one space of the at least three spaces. The number of the openings is not limited to two, i.e., openings 36, 37. The number of the openings and the opening area of each opening may be freely determined in accordance with the shape of the sub-tank 20 and performance of the jet pump as appropriate. The sub-chamber 35 may receive another component such as a thermistor used for a level sensor, in addition to the first jet pump, or instead of the first jet pump. A jet pump may be additionally disposed in the sub-chamber to transfer fuel from the sub-chamber to the outside of the sub-chamber. In this case, the openings 36, 37 may be plugged. Various modifications and alternations may be diversely made to the above embodiments without departing from the spirit of the present invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>A fuel feed apparatus disclosed in JP-A-9-268957 is capable of stably feeding fuel from an inside of a fuel tank to the outside, even when an amount of fuel received in the fuel tank decreases. The fuel feed apparatus includes a sub-tank that is received in the fuel tank. The inner space of the sub-tank needs to be partitioned into multiple chambers to individually receive components in the fuel feed apparatus having a specific structure. A fuel pump may be arranged in one of the separated chambers. In this structure, fuel can be circulated in the chamber receiving the fuel pump. However, fuel may remain in another chamber, in which the fuel pump is not provided, and the remaining fuel may be deteriorated due to oxidization. As a result, components of the fuel feed apparatus such as the sub-tank may be corroded due to the deteriorated fuel, and proper operation of components may not be maintained. | <SOH> SUMMARY OF THE INVENTION <EOH>In view of the foregoing problems, it is an object of the present invention to produce a fuel feed apparatus that is capable of reducing fuel remaining in a sub-tank. According to the present invention, a fuel feed apparatus, which is at least partially received in a fuel tank, includes a sub-tank and a fuel pump. The sub-tank is received in the fuel tank. The sub-tank has an inner space that is partitioned into at least a first chamber and a second chamber. The fuel pump is arranged in the first chamber. The fuel pump discharges fuel, which is received in the sub-tank, to the outside of the fuel tank. The second chamber defines an opening, through which the second chamber communicates with the outside of the sub-tank such that fuel accumulated in the second chamber is capable of being exhausted to the outside of the sub-tank through the opening. | 20050126 | 20070109 | 20050804 | 63299.0 | 0 | MOULIS, THOMAS N | FUEL FEED APPARATUS HAVING OPENING IN SUB-TANK | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,042,022 | ACCEPTED | Jet pump with improved start-up properties and fuel delivery system equipped with such jet pump | The present invention relates to a jet pump having a first inlet duct, a second inlet duct and an outlet duct having an outlet end, wherein the ducts are in fluid communication with each other at a central volume portion. The jet pump also includes a sleeve formed with a closed end at the bottom and partially enclosing said outlet duct. The sleeve has a lateral opening therein at a predetermined height above the outlet end of said outlet duct. A continuous flowpath with different flow directions is also present within the sleeve along the inner and outer surfaces of said outlet duct towards the lateral opening. The jet pump can be advantageously used in fuel delivery system with saddle fuel tanks. | 1. A jet pump with improved start-up properties comprising: a pump body having a first inlet duct, a second inlet duct and an outlet duct, said ducts defining respective hollow interiors communicating with each other at a mixing portion; the hollow interior of said outlet duct defines a diffusing portion having an increasing inner cross-section away from the mixing portion and having an outlet end; the first inlet duct includes an inlet end communicating with a nozzle portion having a decreasing inner cross-section towards the mixing portion and defining an orifice opening towards the mixing portion; the second inlet duct is arranged at an angle relative to the first inlet and outlet ducts; a sleeve at least partially covering and arranged around the outlet duct; the sleeve having an open end, a closed end, a solid wall and at least one lateral opening defined through the wall between the open and closed ends; the outlet end of the outlet duct being located deeper in the sleeve than the lateral opening, whereby a continuous flowpath with different flow directions is formed within the sleeve along the inner and outer surfaces of the outlet duct towards the lateral opening. 2. The jet pump according to claim 1, wherein the open end of the sleeve is provided with a rim. 3. The jet pump according to claim 2, wherein the outlet duct is provided with a flange on its outer surface to bear against the rim of the open end for controlling the depth of insertion of the outlet duct into the sleeve. 4. The jet pump according to claim 1, wherein the sleeve and the outlet duct have a common axis. 5. The jet pump according to claim 1, wherein said opening is made in the form of a slot in the wall of the sleeve. 6. The jet pump according to claim 5, wherein the slot extends generally parallel with said axis from the open end of the sleeve towards the closed end thereof. 7. The jet pump according the claim 6, wherein the slot extends parallel to an axis, the axis being a common axis between the sleeve and the outlet duct. 8. The jet pump according to claim 1, wherein at least one fixing tab fitting into a groove formed in the wall of the sleeve is present on the outer surface of the outlet duct for preventing swivel of the pump body within the sleeve around said axis. 9. The jet pump according to claim 1, wherein the outlet duct and the inner surface of the sleeve are spaced apart along the flowpath. 10. The jet pump according to claim 1, wherein it comprises fastening means for a firm installation. 11. The jet pump according to claim 1, wherein the first inlet duct and the outlet duct have a common axis. 12. A fuel delivery system for a vehicle equipped with an engine comprising: a saddle fuel tank having an active side and a passive side; a reservoir installed into the active side of the fuel tank, the reservoir having a check-valve in its bottom and a spillway on its top; a fuel pump mounted in the reservoir, the fuel pump having an inlet and an outlet; a fuel diverter in the form of a T-valve having an inlet in fluid communication with the outlet of the fuel pump, a first outlet, and a second outlet in fluid communication with the engine; a jet pump mounted to the reservoir, wherein the jet pump having a first inlet duct having an orifice, the first inlet duct being in fluid communication with the first outlet of the fuel diverter, the jet pump having a second inlet duct in fluid communication with the passive side of the saddle fuel tank, and the jet pump having an outlet duct provided with an outlet end, the outlet being in fluid communication with the inside of the reservoir; and a fuel delivery hose having an inlet located within the passive side of the saddle fuel tank and an outlet connected to the second inlet duct of the jet pump; the jet pump having a sleeve formed with a closed end at the bottom and partially endosing the outlet duct, the sleeve including a lateral opening therein at a predetermined height above the outlet end of the outlet duct. 13. The fuel delivery system according to claim 12, wherein the inner diameter of the orifice in the jet pump is in the range of 0.4-0.5 mm. 14. A fuel delivery system for a vehicle equipped with an engine, comprising: a saddle fuel tank having an active side and a passive side; a reservoir installed into the active side of the fuel tank, the reservoir having a check-valve in its bottom and a spillway on its top; a fuel pump mounted in the reservoir, the fuel pump having an inlet and an outlet; a conduit providing fluid communication between the fuel pump and the engine, said conduit having a first end and a second end, said first end being connected to the outlet of the fuel pump and the second end being connected to the engine; a return supply tube having a first end and a second end, the first end of the return supply tube being connected to the engine; a jet pump mounted to the reservoir, wherein the jet pump having a first inlet duct having an orifice, the duct being connected to the second end of the return supply tube, the jet pump having a second inlet duct in fluid communication with the passive side of the saddle fuel tank, and the jet pump having an outlet duct provided with an outlet end, the duct being in fluid communication with the inside of the reservoir; and a fuel delivery hose having an inlet located within the passive side of the saddle fuel tank and an outlet connected to the second inlet duct of the jet pump; the jet pump having a sleeve formed with a closed end at the bottom and partially endosing the outlet duct, the sleeve including a lateral opening therein at a predetermined height above the outlet end of the outlet duct. 15. The fuel delivery system according to claim 14, wherein the engine is a diesel oil operated engine, and the inner diameter of the orifice in the jet pump is in the range of 2.0-2.5 mm. | BACKGROUND 1. Field of the Invention The invention relates to a jet pump with improved start-up properties. The jet pump can be used for the continuous supply of liquid fuel from remote containers or tanks to devices making use of the fuel. The invention further relates to the use of the jet pump in fuel delivery systems of internal combustion motor vehicles, especially in those systems which are equipped with a so-called saddle fuel tank. 2. Related Technology Nowadays, saddle fuel tanks are widely used by the motor vehicle industry because of their greater fuel storing capacity compared to that of standard fuel tanks. Saddle fuel tanks are most frequently used with four wheel driven (4WD) and rear wheel driven vehicles and have two compartments connected by a channel located within the tank just above the saddle portion thereof. As a consequence of the two compartments, a special fuel delivery system should be installed in this type of fuel tanks to transfer the fuel from one of the compartments (“passive side”) to the other (“active side”) and then to the engine. To achieve this, in most cases in-tank fuel supply units are provided within the tank. U.S. Pat. No. 6,619,272 describes an in-tank fuel supply unit to be mounted in the passive side of the fuel tank. The supply unit has a fuel pump in the fluid communication with a jet pump and pumps fuel from the passive side of the tank to the active side thereof when a second pump located in the active side is operating. Nevertheless, the jet pump can operate only if the fuel level is high enough to flood at least partially the mixing chamber of the jet pump. The jet pump cannot prime its mixing chamber by its driving flow, because all the flow collected in the mixing chamber is returned into the fuel tank when the fuel level is too low. Therefore, the operation of the jet pump is not independent of the fuel level; a well-defined minimal fuel level is required for the jet pump to start its operation. A further disadvantage of this solution dearly is the use of two fuel pumps, one in the active side and one in the passive side that makes the fuel delivery system more complicated and more expensive to manufacture. Furthermore, the use of two fuel pumps also raises the risk of a malfunction in the system. In view of the background art, there is a need for such fuel delivery systems which are simple in construction, i.e. they contain active components only within the active side of the tank, reliable and cheap to manufacture. Furthermore, there is also a need for an improved jet pump that can be used in this type of the fuel delivery systems and enables reliable passage of fuel from the passive side of the saddle fuel tank, even if the fuel level within the tank is extremely low. In other words, there is a need for a jet pump being capable of operating independently of the fuel level within the saddle fuel tank. The present invention achieves these objectives by providing a jet pump having a first inlet duct, a second inlet duct and an outlet duct having an outlet end, wherein said ducts are in fluid communication with each other at a central volume portion. The jet pump also comprises a sleeve formed with a closed end at the bottom and partially endosing said outlet duct. The sleeve has a lateral opening therein at a predetermined height above the outlet end of the outlet duct. Furthermore, a continuous flowpath with different flow directions is present within the sleeve along the inner and outer surfaces of the outlet duct towards the lateral opening. BRIEF DESCRIPTION OF THE DRAWINGS The invention, its operation and further advantages will be explained in detail with reference to the accompanying drawings, wherein: FIG. 1 shows the exploded cross-sectional view of a preferred embodiment of the jet pump embodying the principles of the invention; FIG. 2 is the cross-sectional view of the jet pump shown in FIG. 1 in its assembled state, that is when the pump body is received by the sleeve; FIGS. 3A to 3C depict the operation of the jet pump according the principles of this invention; and FIGS. 4A and 4B are schematic view of two possible embodiments of the fuel delivery system equipped with jet pumps embodying the principles of the present invention. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a jet pump 1 of the present invention comprises basically a pump body 1A and a pump sleeve 1B. The pump body 1A has a first inlet duct 10, a second inlet duct 20 and an outlet duct 30. The first inlet duct 10 has an inlet end 12 and a nozzle portion 14. Outer surface 13 of the inlet duct 10, or at least a part thereof in the vicinity of the inlet end 12 is provided with ribs 15 for connection with an end portion of a first fuel delivery hose 54 (see FIG. 2). The inlet end 12 defines a hollow interior ending in the nozzle portion 14, which has a forwardly tapered inner surface, i.e. the inner cross-section of the nozzle portion 14 decreases gradually and terminates in a small orifice 16. The outlet duct 30 comprises a mixing portion 32 close to the orifice 16 and opening into a diffusing portion 34. The inner cross-section of the mixing portion 32 is substantially constant, while the inner cross-section of the diffusing portion 34 increases gradually in size in downward direction. The diffusing portion 34 terminates in an outlet end 36 at the end of the outlet duct 30. The first inlet duct 10 and the outlet duct 30 are coaxial, i.e. they have a common axis 5. The second inlet duct 20 closes an angle with this axis 5. The inner ends of the first inlet duct 10, the second inlet duct 20 and the outlet duct 30 communicate in a common central volume portion. Preferably, the second inlet duct 20 is perpendicular to the axis 5, this the pump body 1A has a T-shape. In this special case, the inlet ducts 10, 20 and the outlet duct 30 meet at the intersection of the T-shape. Furthermore, the outer end of the second inlet duct 20 is adapted for connection to a second fuel delivery hose 56 (see FIG. 2). The sleeve 1B has an open end 40 with a rim 44, a closed end 41 and a solid cylindrical wall 46 extending between the two ends 40, 41. The inner surface of the wall 46 and the inner surface of the closed end 41 constitute the total inner surface 42 of the sleeve 1B. The sleeve 1B has furthermore at least one lateral opening 43 formed though the wall 46 between the two ends 40, 41. This opening 43 allows the fluid communication between the inside and the outside of the sleeve 1B. Furthermore, the outlet end 36 of the outlet duct 30 is in fluid communication with said opening 43 via a continuous flowpath 45 with different flow directions bound by the inner surface 42 of the sleeve 1B. Referring now to FIG. 2, wherein the pump body 1A and the pump sleeve 1B are assembled to form the jet pump 1 according to the invention. The sleeve 1B covers the outlet duct 30 at least along the lower region thereof. As it is also shown in FIG. 2, to enable a control on how deep the outlet duct 30 can be inserted into the sleeve 1B, a flange 37 is provided on the outer surface of the outlet duct 30. Generally, the position of the flange 37 on the outlet duct 30 is chosen in such a way that if the pump body 1A is arranged within the sleeve 1B in its operational position, i.e. when the flange 37 abuts the rim 44 of the sleeve 1B, the outlet end 36 of the outlet duct 30 cannot reach the closed end 41 of the sleeve 1B. Described another way, the distance between the outlet end 36 and the closed end 41 is shorter than the distance between the opening 43 in the wall 46 and the dosed end 41. The opening 43 can take various shapes. In one embodiment of the jet pump 1, it is formed as one or more through bores in the wall 46. In a preferred embodiment, the opening 43 is prepared as one or more separate slots which extends/extend from the open end 40 of the sleeve 1B towards the closed end 41 thereof parallel with the axis 5, as it is shown in FIGS. 1 and 2. In certain further embodiments of the jet pump 1, to prevent any swivel of the pump body 1A around the axis 5 within the sleeve 1B, at least one fixing tab 38 is provided on the outer surface of the outlet duct 30; when the jet pump 1 is fully assembled, every fixing tab 38 engages a correspondent slot formed in the wall 46 especially for this purpose. The fixing tab(s) 38 should not obstruct fluid flow along the inner and outer surfaces of the outlet duct 30. As the jet pump 1 is intended to be used in a fuel delivery system of a motor vehicle, it is preferably provided with suitable fastening means 39 for enabling its mounting into the fuel delivery system, as illustrated schematically in FIGS. 4A and 4B. The fastening means 39 can be arranged on the outer surface of the outlet duct 30 or it can be formed integrally therein. In most cases, the fastening means 39 are formed as catches to be engaged firmly the correspondent receiving elements formed in certain components of the fuel delivery system. The fastening means 39 can locate fully outside the sleeve 1B (see the embodiment shown in FIG. 2) or special grooves can be prepared for the fastening means 39 in the wall 46 in order that they could reach and engage said receiving elements. The lateral opening 43 can also take the role of these grooves, however, care should be taken that the fastening means 39 cannot obstruct the opening 43. With respect to the inner/outer dimensions of the jet pump 1 according to the invention it should be noted that the inner diameter of the orifice 16 depends on the planned application of the jet pump 1; in general it is much smaller than the inner diameter of the mixing portion 32 and that of the second inlet duct 20. In particular, the inner diameter of the orifice 16 is preferably in the range of about 0.4-2.5 mm, the inner diameter of the second inlet duct 20 is preferably between about 4.0 and 5.0 mm, the inner diameter of the mixing portion 32 is preferably about 5.0 mm, and the outer diameter of the outlet duct 30, just at the outlet end 36, is preferably in the range of about 7.0-8.0 mm. Furthermore, the full length and the inner diameter of the sleeve 1B is preferably about 43.0 mm and about 11.0 mm, respectively. The distance between the dosed end 41 and the opening 43 is preferably 17.0-18.0 mm, while the distance between the closed end 41 and the outlet end 36 is preferably 6.0-10.0 mm. Thus, in an exemplary jet pump 1 with the above measures, the opening 43 is formed at about the middle of the sleeve 1B. Moreover, if the axes of the sleeve 1B and the outlet duct 30 fall on the same line, then the inner surface 42 of the sleeve 1B will not get into contact with the outlet duct 30 along the flowpath 45. Referring now to FIGS. 4A and 4B, the jet pump according to the invention is shown installed into different types of fuel delivery systems 100 and 100′, respectively. FIG. 4A illustrates a fuel delivery system 100 according to the present invention, useful essentially for petrol-operated motor vehicles (not shown) equipped with a saddle fuel tank 110, which stores fuel (in this case petrol, not shown) used to power the vehicle's engine 120. An upward projection 114 in the bottom wall of the saddle fuel tank 110 separates the tank 110 into two compartments, herein referred to as an active side 112 and a passive side 116 connected by a channel 118. In normal operation, fuel is stored in both the active side 112 and the passive side 116 of said saddle fuel tank 110. In the active side 112 a reservoir 140 is mounted onto the bottom wall of the fuel tank 110. The reservoir 140 is provided with a check-valve 142 on its bottom to allow seeping of fuel from the active side 112 into the reservoir 140 at extremely low fuel levels within the active side of the tank 110. The reservoir 140 is further provided with an open spillway 146 on its top to enable the overflow of fuel being in excess amount within the reservoir 140. An electric fuel pump 130 and a jet pump 1 are also installed in the reservoir 140. The jet pump 1 is attached to the top of the reservoir 140 by means of its fastening means 39 (see e.g. FIG. 1) in such a position that its sleeve 1B and its outlet duct 30 within the sleeve 1B (see e.g. FIG. 1) penetrate into the interior of the reservoir 140, while the first and second inlet ducts 10, 20 of the jet pump 1 remain outside the reservoir 140. The fuel pump 130 is operated by a power supply (not shown). The fuel pump 130 has an outlet 132 which is connected to an inlet 152 of a three-way fuel diverter 150, preferably provided in the form of a T-valve or connector, via a fuel delivery hose 55. The diverter 150, besides the inlet 152, has two outlets 154 and 156; one of the outlet 154 is connected to the first inlet duct 10 of the jet pump 1 via a fuel delivery hose 54 to direction drive the jet pump 1, while the other outlet 156 is connected to the engine 120 via a conduit 57. As it is suggested by the working “fuel diverter”, the three-way fuel diverter 150 passes the fuel supplied by the fuel pump 130 in two separate directions, namely to the engine 120 and to the jet pump 1. Furthermore, the second inlet duct 20 (see e.g. FIG. 1) of the jet pump 1 communicates with the passive side 116 of the saddle fuel tank 110 via the fuel delivery hose 56 extending preferably within the channel 118 over the projection 114. The fuel delivery hose 56 has an outlet 51 connected to the second inlet duct 20 of the jet pump 1 and an inlet 52 located in a lower most portion of the passive side 116 of the tank 110. Considering the fuel delivery system 100 of FIG. 4A, the function of the fuel pump 130 is to pump fuel from the reservoir 140, and hence from the active side 112, to the vehicle's engine 120 in accordance with the engine's 120 needs. The function of the jet pump 1 is to draw fuel from the passive side 116 into the active side 112 of the fuel tank 110 reliably, even if the fuel level is extremely low within the tank 110. FIG. 4B shows a modified fuel delivery system 100′, useful in particular for diesel oil operated motor vehicles. The difference between this system 100′ and the system 100 illustrated in FIG. 4A is that here no fuel diverter is used, but the outlet 132 of the fuel pump 130 is directly connected to the engine 120 via a conduit 57′ and a return supply tube 58 leads from the engine 120 to the first inlet duct 10 (see e.g. FIG. 1) of the jet pump 1′. The result of this modification is that, in the present embodiment, the fuel pump 130 drives indirectly the jet pump 1′ (i.e. via the engine 120 by means of the fuel supplied in excess to the engine 120). Further components of system 100′, the function and the mutual arrangement thereof are analogous with the components of the system 100, and their functions and mutual arrangement, thus the system 100′ is not discussed in more detail. Referring now to FIGS. 3A to 3C, the operation of the jet pump 1, 1′ according to the present invention is as follows. FIG. 3A shows the first few moments of the jet pump's operation; the engine has been just switched on and the electric fuel pump 130 just started to deliver fuel to the engine 120. A preset portion of the fuel delivered towards the engine 120 enters into the first inlet duct 10 of the jet pump 1 through either the fuel diverter 150 (in system 100 shown in FIG. 4A) or the engine 120 as a return flow of excessively supplied, unused fuel (in system 100′ shown in FIG. 4B). As it is well-known for a person skilled in the relevant art, the fuel portion always represents a more or less constant flow rate, which is due to either a control on the suction force exerted by the fuel pump 130—wherein the control is realized by changing the voltage applied on the fuel pump 130 in accordance with the engine's fuel requirement—(as happens in the system 100) or the constant flow rate of the return fuel flow itself (as happens in the system 100′). The portion of the fuel runs through the orifice 16 (see e.g. FIG. 1), then through the outlet duct 30 and begins to fill up the flowpath 45 closed down by the pump sleeve 1B. At this stage, the diffusing portion 32 is not yet filled with fuel, and the jet pump 1 exerts a suction effect on the fuel being present in the passive side 116 of the saddle fuel tank 110 (see e.g. FIG. 4A), which is due to the depression within the outlet duct 30 caused by the high speed fuel jet passing through the orifice 16. This suction effect is, however, insufficient to lift up the fuel to the jet pump 1 in the fuel delivery hose 56. As a consequence, fuel transfer from the passive side 116 to the active side 112 of the saddle fuel tank 110 cannot start. As shown in FIG. 3B, the fuel jet flowing out of the orifice 16 quickly fills up the flowpath 45 to a level which is determined basically by the position of the lateral opening 43 formed in the wall 46 of the sleeve 1B. This fuel level is high enough to fill up at least partially the outlet duct 30, i.e. the diffusing portion 34 and/or the mixing portion 32. Now, the fuel jet leaving the orifice 16 collides with the fuel already being present in the outlet duct 30. During the collision, bubbles and foam are created. By the bubbles and the foaming mixture of air and fuel appears. The air comes from the upper part of the mixing portion 32 and from the fuel delivery hose 56 connected to the second inlet duct 20 of the jet pump 1. The fuel jet with high velocity transfers its momentum to the air-fuel mixture. Due to the transferred momentum, the air-fuel mixture moves out of the diffusing portion 34 and/or mixing portion 32, vacuum appears in the neighborhood of the orifice 16, and hence in the fuel delivery hose 56. Due to the increased vacuum, the fuel transfer from the passive side 116 to the active side 112 of the saddle fuel tank 110 (see e.g. FIG. 4A) starts. As the air is drawn out of the fuel delivery hose 56, all the hose 56, the mixing portion 32 and the diffusing portion 34 are filled up with fuel in their full lengths, and no air will be present within the jet pump 1 any longer. From now on, the jet pump 1 operates like an ordinary jet pump having no sleeve; until the engine 120 operates, the pump sleeve 1B surrounding the outlet duct 30 has no influence on the operation of the jet pump 1 any more, except constituting an increased flow resistance. Briefly summarized: such a jet pump is developed that is capable of initiating fuel transport from the passive side into the active side of a saddle fuel tank without the need for the fuel delivery hose 56 to be primed prior to the start of the jet pump's operation. Thus, to prevent draining of said hose 56 when the system 100, 100′ is not in operation, no foot valve is required in the inlet 52 of said hose 56 (see FIG. 4A). Furthermore, the increase in the suction effect of the jet pump according to the invention as a result of the momentum transfer described allows the manufacturing of a jet pump having an orifice 16 greater in diameter compared to the orifice diameters of jet pumps without sleeves presently used in fuel delivery systems. Hence, flow rates through jet pumps according to the invention can be reduced which results in better fuel economy of the vehicles engine 120. Furthermore, due to the construction of the jet pump, the proposed fuel delivery systems 100, 100′ provide improved start-up ability at any fuel level within the tank 110 and at any angle of inclination of the vehicle (in normal use). The foregoing discussion discloses and describes a preferred embodiment of the invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that changes and modifications can be made to the invention without departing from the true spirit and fair scope of the invention as defined in the following claims. | <SOH> BACKGROUND <EOH>1. Field of the Invention The invention relates to a jet pump with improved start-up properties. The jet pump can be used for the continuous supply of liquid fuel from remote containers or tanks to devices making use of the fuel. The invention further relates to the use of the jet pump in fuel delivery systems of internal combustion motor vehicles, especially in those systems which are equipped with a so-called saddle fuel tank. 2. Related Technology Nowadays, saddle fuel tanks are widely used by the motor vehicle industry because of their greater fuel storing capacity compared to that of standard fuel tanks. Saddle fuel tanks are most frequently used with four wheel driven (4WD) and rear wheel driven vehicles and have two compartments connected by a channel located within the tank just above the saddle portion thereof. As a consequence of the two compartments, a special fuel delivery system should be installed in this type of fuel tanks to transfer the fuel from one of the compartments (“passive side”) to the other (“active side”) and then to the engine. To achieve this, in most cases in-tank fuel supply units are provided within the tank. U.S. Pat. No. 6,619,272 describes an in-tank fuel supply unit to be mounted in the passive side of the fuel tank. The supply unit has a fuel pump in the fluid communication with a jet pump and pumps fuel from the passive side of the tank to the active side thereof when a second pump located in the active side is operating. Nevertheless, the jet pump can operate only if the fuel level is high enough to flood at least partially the mixing chamber of the jet pump. The jet pump cannot prime its mixing chamber by its driving flow, because all the flow collected in the mixing chamber is returned into the fuel tank when the fuel level is too low. Therefore, the operation of the jet pump is not independent of the fuel level; a well-defined minimal fuel level is required for the jet pump to start its operation. A further disadvantage of this solution dearly is the use of two fuel pumps, one in the active side and one in the passive side that makes the fuel delivery system more complicated and more expensive to manufacture. Furthermore, the use of two fuel pumps also raises the risk of a malfunction in the system. In view of the background art, there is a need for such fuel delivery systems which are simple in construction, i.e. they contain active components only within the active side of the tank, reliable and cheap to manufacture. Furthermore, there is also a need for an improved jet pump that can be used in this type of the fuel delivery systems and enables reliable passage of fuel from the passive side of the saddle fuel tank, even if the fuel level within the tank is extremely low. In other words, there is a need for a jet pump being capable of operating independently of the fuel level within the saddle fuel tank. The present invention achieves these objectives by providing a jet pump having a first inlet duct, a second inlet duct and an outlet duct having an outlet end, wherein said ducts are in fluid communication with each other at a central volume portion. The jet pump also comprises a sleeve formed with a closed end at the bottom and partially endosing said outlet duct. The sleeve has a lateral opening therein at a predetermined height above the outlet end of the outlet duct. Furthermore, a continuous flowpath with different flow directions is present within the sleeve along the inner and outer surfaces of the outlet duct towards the lateral opening. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>The invention, its operation and further advantages will be explained in detail with reference to the accompanying drawings, wherein: FIG. 1 shows the exploded cross-sectional view of a preferred embodiment of the jet pump embodying the principles of the invention; FIG. 2 is the cross-sectional view of the jet pump shown in FIG. 1 in its assembled state, that is when the pump body is received by the sleeve; FIGS. 3A to 3 C depict the operation of the jet pump according the principles of this invention; and FIGS. 4A and 4B are schematic view of two possible embodiments of the fuel delivery system equipped with jet pumps embodying the principles of the present invention. detailed-description description="Detailed Description" end="lead"? | 20050125 | 20060627 | 20050825 | 73773.0 | 0 | MILLER, CARL STUART | JET PUMP WITH IMPROVED START-UP PROPERTIES AND FUEL DELIVERY SYSTEM EQUIPPED WITH SUCH JET PUMP | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,042,116 | ACCEPTED | Light emitting diode and fabrication method thereof | A light emitting diode. The light emitting diode comprises a lead frame, a plurality of light emitting chips in the lead frame, and a molding unit in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure. | 1. A light emitting diode, comprising: a lead frame; a plurality of light emitting chips in the lead frame; and a molding unit in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure. 2. The light emitting diode as claimed in claim 1 is a monochrome light emitting diode, a white light emitting diode or a full color light emitting diode. 3. The light emitting diode as claimed in claim 1, wherein the molding unit is transparent. 4. The light emitting diode as claimed in claim 1, wherein the periodic microstructure comprises conical protrusions or pyramidal protrusions. 5. The light emitting diode as claimed in claim 4, wherein the pyramidal protrusions comprise symmetric pyramidal protrusions or asymmetric pyramidal protrusions. 6. The light emitting diode as claimed in claim 5, wherein the symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 7. The light emitting diode as claimed in claim 1, wherein the periodic microstructure comprises flat top conical protrusions or flat top pyramidal protrusions. 8. The light emitting diode as claimed in claim 7, wherein the flat top pyramidal protrusions comprise flat top symmetric pyramidal protrusions or flat top asymmetric pyramidal protrusions. 9. The light emitting diode as claimed in claim 8, wherein the flat top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the flat top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 10. The light emitting diode as claimed in claim 1, wherein the periodic microstructure comprises round top conical protrusions or round top pyramidal protrusions. 11. The light emitting diode as claimed in claim 10, wherein the round top pyramidal protrusions comprise round top symmetric pyramidal protrusions or round top asymmetric pyramidal protrusions. 12. The light emitting diode as claimed in claim 11, wherein the round top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the round top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 13. The light emitting diode as claimed in claim 1, wherein the microstructure has a size of about 20 um˜1 mm. 14. A light emitting diode fabrication method, comprising: providing a lead frame; providing a plurality of light emitting chips in the lead frame; patterning a surface of a molding unit to form a periodic microstructure; and setting the molding unit in an optical path of the light emitting chips. 15. The light emitting diode fabrication method as claimed in claim 14, wherein the light emitting diode is a monochrome light emitting diode, a white light emitting diode or a full color light emitting diode. 16. The light emitting diode fabrication method as claimed in claim 14, wherein the molding unit is transparent. 17. The light emitting diode fabrication method as claimed in claim 14, wherein the patterning step comprises modeling step. 18. The light emitting diode fabrication method as claimed in claim 17, wherein the molding step employs a mold having a microstructure thereon. 19. The light emitting diode fabrication method as claimed in claim 14, wherein periodic microstructure comprises conical protrusions or pyramidal protrusions. 20. The light emitting diode fabrication method as claimed in claim 19, wherein the pyramidal protrusions comprise symmetric pyramidal protrusions or asymmetric pyramidal protrusions. 21. The light emitting diode fabrication method as claimed in claim 20, wherein the symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 22. The light emitting diode fabrication method as claimed in claim 14, wherein the periodic microstructure comprises flat top conical protrusions or flat top pyramidal protrusions. 23. The light emitting diode fabrication method as claimed in claim 22, wherein the flat top pyramidal protrusions comprise flat top symmetric pyramidal protrusions or flat top asymmetric pyramidal protrusions. 24. The light emitting diode fabrication method as claimed in claim 23, wherein the flat top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the flat top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 25. The light emitting diode fabrication method as claimed in claim 14, wherein the periodic microstructure comprises round top conical protrusions or round top pyramidal protrusions. 26. The light emitting diode fabrication method as claimed in claim 25, wherein the round top pyramidal protrusions comprise round top symmetric pyramidal protrusions or round top asymmetric pyramidal protrusions. 27. The light emitting diode fabrication method as claimed in claim 26, wherein the round top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal; the round top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. 28. The light emitting diode fabrication method as claimed in claim 14, wherein the microstructure size is smaller than the light emitting chips size. 29. The light emitting diode fabrication method as claimed in claim 14, wherein the microstructure has a size of about 20 um˜1 mm. | BACKGROUND The invention relates to a light emitting diode (LED), and more particularly to a LED with molding unit and fabrication method thereof. Multi-chip LEDs comprise a plurality of different color light emitting chips. The most common white multi-chip LED is a RGB LED. RGB LEDs comprise red (R), green (G) and blue (B) light emitting chips for obtaining white light. FIG. 1 shows a bullet type RGB LED structure. Red light emitting chip R, green light emitting chip G and blue light emitting B are disposed in the lead frame 10. The sidewalls of lead frame 10 comprise a highly reflective layer with a curvature for condensing the light emitted from the light emitting chips R, G and B. This type of LED further comprises lens type molding unit 12 to improve directionality thereof. A RGB LED has a good color mixing, the one would not see different color at different viewing angle. The light emitting chips R, G and B are positioned in different positions in the lead frame 10, however, the color-mixing effect of the bullet type LED is reduced. The lens type molding unit 12 reduces the color-mixing effect. FIG. 2 shows a surface-mount device (SMD) RGB LED structure. The SMD RGB LED has no lens type molding unit, so its directionality is worse than the bullet type RGB LED. Furthermore, the surface of the lead frame 20 of the SMD RGB LED is uneven, thus the color-mixing effect and color uniformity are improved. At the same time, the uneven surface reflects and even scatters light, both of which decrease the SMD RGB LED directionality. In short, the SMD RGB LED improves color-mixing but reduces directionality. Thus, the bullet type LED has good directionality, but bad color-mixing; the SMD type LED has bad directionality, but good color-mixing. Hence, there is a need for a LED with good directionality and good color-mixing characteristics. SUMMARY Accordingly, embodiments of the invention provide a light emitting diode and fabrication method thereof. A light emitting diode comprises a lead frame, a plurality of light emitting chips disposed in the lead frame, and a molding unit disposed in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure. A light emitting diode fabrication method comprises providing a lead frame, providing a plurality of light emitting chips in the lead frame, patterning a surface of a molding unit to form a periodic microstructure, and setting the molding unit disposed in an optical path of the light emitting chips. DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-section illustrating a conventional light emitting diode; conventional light emitting diode; FIG. 3A is a cross-section illustrating a light emitting diode of the embodiments; FIG. 3B is a cross-section illustrating another light emitting diode of the embodiments; FIG. 4A˜4F are top-views illustrating the molding unit surface microstructure of the light emitting diode of the embodiments; FIG. 5 is a schematic illustrating the half vertex angle of the light emitting diode; FIG. 6A is a beam pattern illustrating the directionality of a conventional light emitting diode; FIG. 6B is a color distribution illustrating the chromatic uniformity of a conventional light emitting diode; FIG. 7A is a beam pattern illustrating the directionality of another conventional light emitting diode; FIG. 7B is a color distribution illustrating the chromatic uniformity of another conventional light emitting diode; FIG. 8A is a beam pattern illustrating the directionality of a light emitting diode of the first embodiment; FIG. 8B is a color distribution illustrating the chromatic uniformity of a light emitting diode of the first embodiment; FIG. 9A is a beam pattern illustrating the directionality at a different half vertex angle of a light emitting diode microstructure of the second embodiment; FIG. 9B is a color distribution illustrating the chromatic uniformity at a different half vertex angle of a light emitting diode microstructure of the second embodiment; FIG. 10 is a color distribution illustrating the chromatic uniformity of different light emitting chips in a given area of a light emitting diode of the third embodiment. DETAILED DESCRIPTION FIGS. 3A and 3B show multi-chip LEDs of the invention. The two LEDs comprise lead frame 10 (FIG. 3A) and lead frame 20 (FIG. 3B) respectively. The lead frame 10 comprises a smooth curved refrective surface to condense light. Two or more light emitting chips are disposed in the lead frame 10 and lead frame 20. In one embodiment, there are three light emitting chips 40, 50 and 60 in the lead frame 10 and lead frame 20 respectively. A main feature of the embodiment is the molding unit 70 with periodic microstructure 72. Molding unit 70 is set in the optical path of the light emitting chips 40, 50 and 60 to condense light and mix color. The Molding unit 70 is transparent and the material thereof comprises epoxy or polymers. The polymers comprise polymethylmethacrylate (PMMA) or polycarbonate (PC). The molding unit 70 may be formed by a molding method. In this molding method, the melted epoxy or polymer mold is put in the mold, and the mold has a periodic microstructure. After solidification, the periodic microstructure of the mold is transferred to the epoxy or polymer molding unit 70 with periodic microstructure 72. The periodic microstructure of the mold may be formed by etching, cutting tools, laser or electron beam. The periodic microstructure 72 of the molding unit 70 is a key feature of the invention. The microstructure comprises conical protrusions (FIG. 4A) or pyramidal protrusions. The pyramidal protrusions comprise symmetric pyramidal protrusions or asymmetric pyramidal protrusions. The symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal (FIG. 4B). The asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal (FIG. 4C), asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. The periodic microstructure 72 of the molding unit 70 also comprises flat top conical protrusions or flat top pyramidal protrusions. The flat top pyramidal protrusions comprise flat top symmetric pyramidal protrusions or flat top asymmetric pyramidal protrusions. The flat top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal (FIG. 4E), symmetric pentangular pyramidal or symmetric hexangular pyramidal. The flat top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. Furthermore, the periodic microstructure 72 of the molding unit 70 comprises round top conical protrusions (FIG. 4F) or round top pyramidal protrusions. The round top pyramidal protrusions comprise round top symmetric pyramidal protrusions or round top asymmetric pyramidal protrusions. The round top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal. The round top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal. In one embodiment, the bottom size of a single microstructure is preferably smaller than the size of the light emitting chip for improving directionality and color-mixing. The single microstructure bottom size is about 20 um˜1 nm, and preferably 20˜200 um. The height of and single microstructure is about 20 um˜1 mm, and preferably 20˜200 um. In one embodiment, the space between the single microstructures is preferably smaller than its bottom size to make sure that the emitted light passing through the molding unit. The space of the single microstructure is about 20 um˜1 nm, and preferably 20˜200 um. The following embodiments are white RGB LED. The 30 present invention is not only used as a RGB LED or a white LED, but also as a white multi-chip LED and other multi-chip LEDs. The directionality and color-mixing are obtained from the following measurement and calculation. Chromatic Light Beam Pattern Intensity and Chromatic Uniformity Calculation First, the three-color light in different “space angles luminous intensity” of the RGB LED of the invention is measured to obtain the RGB LED beam pattern. The directionality of RGB LED is determined by the FMWH of the beam pattern. The smaller the FMWH is, the better directionality of the RGB LED is. The RGB LED 1960 CIE UCS color coordinates in respective space angle are obtained form the beam pattern and 20 mA spectra data of the red, green and blue light emitting chips. The chromatic aberrations of RGB LED in each space angles are calculated according to beam pattern, and the chromatic aberration definition as follows: Δuv=[(u−u0)2−(v−v0)2]1/2 wherein (u−u0) is the difference of the chromatic coordination at the RGB LED mechanical center, and (v−v0) is the difference of the chromatic coordination at each point of the RGB LED. A smaller chromatic aberration shows a higher chromatic uniformity of the device. In the invention, three space cross-sections 0°, 45° and 90° are analyzed to obtain the LED chromatic light space symmetry. If the chromatic aberration is smaller than 0.008, it is difficult for the human eye to detect the color change. In practice, the color change must be unobvious (chromatic aberration <0.008) in ±30° space angle of LED. First Comparative Embodiment In this embodiment, the RGB LED structure is the same as FIG. 1. The curvature radius of lens type molding unit 12 is 2.5 mm. The chromatic light beam pattern distribution and chromatic uniformity of the RGB LED of this embodiment are shown in FIGS. 6A and 6B. Second Comparative Embodiment In this embodiment, the RGB LED structure is the same as FIG. 2. The chromatic light beam pattern distribution and chromatic uniformity of the RGB LED of this embodiment are shown in FIGS. 7A and 7B. First Embodiment In this embodiment, the RGB LED structure is the same as FIG. 3B. Its microstructure 72 is conical protrusions with 46 half vertex angle (FIG. 5). The chromatic light beam pattern distribution and chromatic uniformity of the RGB LED of this embodiment are shown in FIGS. 8A and 8B. Second Embodiment In this embodiment, the RGB LED structures are the same as FIG. 3B. The microstructures 72 of the RGB LEDs are conical protrusions with 15°, 40°, 60° and 80° half vertex angle (FIG. 5). The chromatic light beam pattern distribution and chromatic uniformity of the RGB LED of this embodiment are shown in FIGS. 9A and 9B. Third Embodiment In this embodiment, the two RGB LED structures are the same as FIG. 3A. The microstructure 72 of the two RGB LEDs are conical protrusions with 46 half vertex angle (FIG. 5). The distance between light emitting chips of one RGB LED is 0.3 mm, another is 0.6 mm. The chromatic uniformity of the RGB LED of this embodiment is show in FIG. 10. Experiment Data and Invention Effect 1. Color-Mixing Improvement The RGB LED of the comparative embodiment 1 is a bullet type LED, and has good directionality and bad color-mixing characteristics. After using the periodic microstructure molding unit (embodiment 1), good directionality and color-mixing characteristics can obtained at the same time: Referring to FIGS. 6A and 8A, the FMWH of the comparative embodiment 1 and embodiment 1 RGB LEDs are about ±40°. In FIGS. 6B and 8B, the chromatic aberration of RGB LED of embodiment 1 is smaller than that of comparative embodiment 1. Furthermore, the three cross-section space aberrations of RGB LED of embodiment 1 are more uniform. That shows the RGB LED of the embodiment 1 not only has better color-mixing but also with better space symmetry. Thus, the molding unit can improve the bullet type LED color-mixing characteristics. 2. Directionality Improvement The RGB LED of the comparative embodiment 2 is SMD LED, and has bad directionality and good color-mixing characteristics. After using the periodic microstructure molding unit (embodiment 2), good directionality and color-mixing characteristics can be obtained at the same time: Referring to FIG. 9B, the RGB LEDs of comparative embodiment 2 and embodiment 2 all have good color-mixing characteristics. In FIG. 9A, the FMHW RGB LEDs of the embodiment 2 are narrower than that of the comparative embodiment 2. That shows the RGB LEDs of embodiment 2 have better directionality. Thus, the molding unit can improve the SMD LED directionality characteristics. 3. Half Vertex Angle Influence Referring to FIGS. 9A and 9B, different vertex angles can influence the directionality and color-mixing characteristics, and the influence can be predicted by optical simulation calculation. 4. Light Emitting Chips distance Influence Referring to FIG. 10, different light emitting chip arrangements can influence the directionality and color-mixing characteristics, and the influence can be predicted by optical simulation calculation. The foregoing description has been presented for purposes of illustration and description. Obvious modifications or variations are possible in light of the above teaching. The embodiments were chosen and described to provide the best illustration of the principles of this invention and its practical application to thereby enable those skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | <SOH> BACKGROUND <EOH>The invention relates to a light emitting diode (LED), and more particularly to a LED with molding unit and fabrication method thereof. Multi-chip LEDs comprise a plurality of different color light emitting chips. The most common white multi-chip LED is a RGB LED. RGB LEDs comprise red (R), green (G) and blue (B) light emitting chips for obtaining white light. FIG. 1 shows a bullet type RGB LED structure. Red light emitting chip R, green light emitting chip G and blue light emitting B are disposed in the lead frame 10 . The sidewalls of lead frame 10 comprise a highly reflective layer with a curvature for condensing the light emitted from the light emitting chips R, G and B. This type of LED further comprises lens type molding unit 12 to improve directionality thereof. A RGB LED has a good color mixing, the one would not see different color at different viewing angle. The light emitting chips R, G and B are positioned in different positions in the lead frame 10 , however, the color-mixing effect of the bullet type LED is reduced. The lens type molding unit 12 reduces the color-mixing effect. FIG. 2 shows a surface-mount device (SMD) RGB LED structure. The SMD RGB LED has no lens type molding unit, so its directionality is worse than the bullet type RGB LED. Furthermore, the surface of the lead frame 20 of the SMD RGB LED is uneven, thus the color-mixing effect and color uniformity are improved. At the same time, the uneven surface reflects and even scatters light, both of which decrease the SMD RGB LED directionality. In short, the SMD RGB LED improves color-mixing but reduces directionality. Thus, the bullet type LED has good directionality, but bad color-mixing; the SMD type LED has bad directionality, but good color-mixing. Hence, there is a need for a LED with good directionality and good color-mixing characteristics. | <SOH> SUMMARY <EOH>Accordingly, embodiments of the invention provide a light emitting diode and fabrication method thereof. A light emitting diode comprises a lead frame, a plurality of light emitting chips disposed in the lead frame, and a molding unit disposed in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure. A light emitting diode fabrication method comprises providing a lead frame, providing a plurality of light emitting chips in the lead frame, patterning a surface of a molding unit to form a periodic microstructure, and setting the molding unit disposed in an optical path of the light emitting chips. | 20050126 | 20080304 | 20060316 | 76732.0 | H01L3300 | 3 | DOLAN, JENNIFER M | LIGHT EMITTING DIODE AND FABRICATION METHOD THEREOF | UNDISCOUNTED | 0 | ACCEPTED | H01L | 2,005 |
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11,042,213 | ACCEPTED | Cemented carbide body | The present invention relates to a cemented carbide body with the following composition: Co: 10-12 wt-%, TaC: <3 wt-%, NbC: 1-5.5 wt-%, TiC: 3-5 wt-% and as rest WC. The cemented carbide body is particularly useful for metal cutting operations requiring high wear resistance, high edge retention and high edge toughness. | 1. Cemented carbide body of the following composition: Co: from about 10-12 wt-%, TaC: <3 wt-%, NbC: from about 1-5.5 wt-%, TiC: from about 3-5 wt-% and WC: as remainder. 2. The cemented carbide body of claim 1 wherein the amount of TaC+TiC+NbC is from about 8-13 wt-%. 3. The cemented carbide body of claim 1 wherein the WC-content is from about 77-79 wt-% 4. The cemented carbide body of claim 1 wherein the average grain size of the WC is from about 0.4-1.5 μm. 5. The cemented carbide body of claim 1 wherein said body has a hardness of from about 1450-1650 HV. 6. The cemented carbide body of claim 5 wherein said body has a hardness of from about 1450-1550 HV. 7. The cemented carbide body of claim 1 wherein the body is provided with a thin wear resistant coating. 8. The cemented carbide body of claim 1 wherein said body is a rotary tool for metal machining. 9. The cemented carbide body of claim 7 wherein said rotary tool for metal machining is a solid carbide twist drill, a twist drill with exchangeable tip or an end mill, hob, circular knife or hollow circular cutter for metal thread/rod shaping. 10. The cemented carbide body of claim 1 having the following composition: Co: 10.5-11.5 wt-%, TaC: 1.8-2.3 wt-%, NbC: 3.5-5 wt-%, TiC: 3.8-4.3 wt-% and WC: as remainder. 11. The cemented carbide body of claim 1 wherein the amount of TaC+TiC+NbC is from about 9-12 wt-%. 12. The cemented carbide body of claim 10 wherein the amount of TaC+TiC+NbC is from about 9-12 wt-%. 13. The cemented carbide body of claim 10 wherein the WC-content is from about 77-79 wt-% 14. The cemented carbide body of claim 1 wherein the average grain size of the WC is about 1 μm. 15. The cemented carbide body of claim 1 wherein: TaC: <2 wt-%, NbC: from about 4-6 wt-%, and NbC+TaC: from about 5-7 wt-%. 16. The cemented carbide body of claim 10 wherein the average grain size of the WC is about 1 μm. 17. The cemented carbide body of claim 15 wherein: TaC: about 0 wt-% and NbC: 5<NbC+TaC<7. 18. The cemented carbide body of claim 10 wherein said body is a saw tip for a metal saw for the sawing of metal. 19. The cemented carbide body of claim 10 wherein said body is a canning tool. 20. Use of a cemented carbide according to claim 1 as a rotary tool for metal machining. 21. The use of claim 20 wherein said rotary tool is a solid carbide twist drill, a twist drill with exchangeable top or an end mill. 22. Use according to claim 20 for rotating machining at a peripheral speed of >150 m/min. 23. Use according to claim 20 wherein said metal is cast iron. | BACKGROUND OF THE INVENTION The present invention relates to a cemented carbide body for use in, e.g., twist drills, particularly useful for metal cutting operations requiring high wear resistance such as drilling in cast iron, etc. Drilling in metals is generally divided into two types: long hole drilling and short hole drilling. Short hole drilling is generally meant drilling to a depth of up to 3-5 times the drill diameter. Long hole drilling places great demands on good chip formation, lubrication, cooling and chip transport. This is achieved through specially developed drill systems with specially designed drill heads attached to a drillstring. The drill head can be of solid cemented carbide but is generally of tool steel provided with a number of inserts of cemented carbide placed in such a way that they together form the cutting edge. With short hole drilling, the demand is not as great and twist drills either of cemented carbide, tool steel or tool steel provided with cemented carbide inserts are used. A twist drill of cemented carbide is usually manufactured from a cylindrical blank which is machined to the desired shape and dimensions particularly to form cutting edges and flutes. Alternatively, the chip flutes are at least preformed during the extrusion operation. As a result of the grinding, sharp edges are formed. A relatively recent type of drill is a drill with an exchangeable drill tip generally made of cemented carbide and removably connected to a drill shank of tool steel. A common reason to failure of a twist drill is excessive wear in the juncture between the main cutting edge and the leading edge. Another reason to failure is, when the cutting speed is increased, plastic deformation due to high temperature in the peripheral part of the cutting edge. EP-A-951576 discloses a cemented carbide drill consisting of a tough core surrounded by a more wear resistant cover. This type of drill is most suitable for toughness demanding drilling applications. OBJECTS AND SUMMARY OF THE INVENTION It is an object of this invention to avoid or alleviate the problems of the prior art. It is also an object of this invention to provide a cemented carbide body having high wear resistance. It is a specific object of the present invention to provide a metal drilling tool with increased tool life in applications requiring good wear resistance. In one aspect of the invention, there is provided a cemented carbide body of the following composition: Co: from about 10-12 wt-%, TaC: <3 wt-%, NbC: from about 1.5-5.5 wt-%, TiC: from about 3-5 wt-% and WC: as remainder. In another aspect of the invention, there is provided the use of the above-defined body as a rotary tool for metal machining. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 shows a twist drill. FIG. 2 shows in about 1200× magnification the microstructure of the cemented carbide according to the invention. FIG. 3 shows the wear development in a performance test of a twist drill according to the present invention (▴) and according to prior art (▪). FIG. 4 shows the wear development in a performance test of a twist drill according to the present invention (▪) and according to prior art (♦). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION It has now surprisingly been found that a cemented carbide with the following composition gives excellent results in drilling operations requiring good wear resistance without suffering from plastic deformation and/or thermal cracking. Co: from about 10-12, preferably from about 10.5-11.5 wt-%, TaC: <3, preferably from about 1-3, most preferably from about 1.8-2.3 wt-%, NbC: from about 1-5.5, preferably from about 2.5-5.5, most preferably from about 3.5-5 wt-%, TiC: from about 3-5, preferably from about 3.8-4.3 wt-% and WC: as rest, preferably from about 76-81, most preferably from about 77-79 wt-%. TaC+TiC+NbC: preferably from about 8-13, most preferably from about 9-12 wt-%. V and/or Cr: preferably <1 wt-%. In an alternative embodiment particularly for metal sawing tips: Co and W as above, TaC: <2, preferably about 0 wt-%, NbC: from about 4 to about 6, preferably 5<NbC+TaC<7 wt-% and NbC+TaC: from about 5 to about 7 wt-%. The average grain size of the WC is from about 0.4-1.5, preferably 0.8-1.5, most preferably about 1, μm determined using linear analysis on a representative number of SEM micrographs. The hardness of the cemented carbide is from about 1450 to 1650, preferably 1450-1550, HV. The body is provided with a wear resistant coating as known in the art such as PVD-TiN, PVD-TiAlN or CVD coating. The body according to the invention can be made with conventional powder metallurgical techniques of milling of powder, forming hard constituents and binder metal, pressing or extruding the milled mixture to cylindrical blanks which are sintered and finally ground to desired shape and dimensions after which the drill is provided with a wear resistant coating as known in the art. The present invention also relates to the use of a cemented carbide according to above as a rotary tool for metal machining such as a solid carbide twist drill, a twist drill with exchangeable tip or an end mill, hob, circular knife or hollow circular cutter for metal thread/rod shaping, in particular at a peripheral speed of >150 m/min. The present invention further relates to the use of a cemented carbide according to the above as a rotary tool for metal machining such as, hob, circular knife, hollow circular cutter for metal thread/rod shaping, in particular a saw tip for a metal saw for metal cutting/sawing at a peripheral speed of >750 m/min or as a wear part especially for metalforming tools, e.g., canning tools. The invention is additionally illustrated in connection with the following Examples which are to be considered as illustrative of the present invention. It should be understood, however, that the invention is not limited to the specific details of the Examples. EXAMPLE 1 Samples were prepared by wet mixing powders of WC, Co, TiC, TaC and NbC to obtain a cemented carbide with a composition of 78.2 wt-% WC, 11.2 wt-% Co, 4.0 wt-% TiC, 2.1 wt-% TaC, 4.5 wt-% NbC and an average WC grain size of about 1 μm. The mixture was, after spray drying, isostatically pressed to cylindrical blanks which were ground to drills of 8 mm diameter. The microstructure is shown in FIG. 2. After grinding the drills were coated with a layer of 4 μm TiAlN using PVD-technique. EXAMPLE 2 Drills from Example 1 were tested in a drilling operation for drilling through holes in cast iron SS0125. As a reference, corresponding drills of Sandvik commercial cemented carbide grade GC 1220 commonly used for drilling in cast iron. The following data were used: Cutting speed: 100 m/min Feed: 0.25 mm/rpm Through holes, 25 mm deep, were drilled with outer coolant. The result is presented in FIG. 3 which shows the wear VBPmax as a function of number of holes drilled for the drill according to the invention (▴) and reference (▪). EXAMPLE 3 Example 2 was repeated at an increased cutting speed of 175 m/min and internal cooling. The result is presented in FIG. 4 which shows the wear VBPmax as a function of number of holes drilled for the drill according to the invention (▪) and reference (♦). Examples 2 and 3 show that the composition of the present invention is between 35% and 50% better in wear resistance in both ordinary and increased cutting speeds. EXAMPLE 4 Samples were prepared by wet mixing powders of WC, Co, TiC, CrC and NbC to obtain a cemented carbide with a composition of 78.8 wt-% WC, 11.2 wt-% Co, 4.0 wt-% TiC, 5.5 wt-% NbC, 0.5 wt-% CrC and an average WC grain size of about 1 μm. The mixture was, after spray drying, uniaxially pressed and sintered to saw tip blanks. EXAMPLE 5 A circular saw blade was made of tips from Example 4. Saw tips of a commodity cemented carbide grade with the composition of 69 wt-% WC, 11 wt-% Co, 10 wt-% TiC, 8.5 wt-% TaC, 1.5 wt-% NbC and an average WC grain size of about 2.0 μm was used as reference material. All saw tip blanks were brazed onto a circular steel blade (φ 285 mm×60 tips) and ground to a width of 2.5 mm. The edge of each tip had a ground chamfer of width 0.2 mm. The tips were placed onto the saw in groups of six tips for each variant. The cutting test material was steel bar type 17Cr3, φ 52 mm. The reference cemented carbide grade is commonly used in circular metal saws for general steel, low carbon steel and stainless steel. The following data were used in the dry saw cutting test: Machine: Noritake Cutting speed: 800 rpm Feed rate: 40 mm/s Machinability additive: Supra 60S with a dropping speed of 1 drop/second The saw tip performance was measured by the flank wear after 10000 passes. Result: The saw tips of the reference grade showed a flank wear of 0.4 mm after 10000 cuts. The saw tips according to the invention had less than 0.15 mm of flank wear. Microchipping along the cutting edge with severe built-up edge (BUE) and heavy smearing could be observed at the edges of the reference grade. The saw tips according to the invention showed a nice wear pattern with good edge retention without micro chipping. Example 5 shows that the flank wear resistance is more than two times higher in the invented grade. The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art without departing from the spirit of the invention. | <SOH> BACKGROUND OF THE INVENTION <EOH>The present invention relates to a cemented carbide body for use in, e.g., twist drills, particularly useful for metal cutting operations requiring high wear resistance such as drilling in cast iron, etc. Drilling in metals is generally divided into two types: long hole drilling and short hole drilling. Short hole drilling is generally meant drilling to a depth of up to 3-5 times the drill diameter. Long hole drilling places great demands on good chip formation, lubrication, cooling and chip transport. This is achieved through specially developed drill systems with specially designed drill heads attached to a drillstring. The drill head can be of solid cemented carbide but is generally of tool steel provided with a number of inserts of cemented carbide placed in such a way that they together form the cutting edge. With short hole drilling, the demand is not as great and twist drills either of cemented carbide, tool steel or tool steel provided with cemented carbide inserts are used. A twist drill of cemented carbide is usually manufactured from a cylindrical blank which is machined to the desired shape and dimensions particularly to form cutting edges and flutes. Alternatively, the chip flutes are at least preformed during the extrusion operation. As a result of the grinding, sharp edges are formed. A relatively recent type of drill is a drill with an exchangeable drill tip generally made of cemented carbide and removably connected to a drill shank of tool steel. A common reason to failure of a twist drill is excessive wear in the juncture between the main cutting edge and the leading edge. Another reason to failure is, when the cutting speed is increased, plastic deformation due to high temperature in the peripheral part of the cutting edge. EP-A-951576 discloses a cemented carbide drill consisting of a tough core surrounded by a more wear resistant cover. This type of drill is most suitable for toughness demanding drilling applications. | <SOH> OBJECTS AND SUMMARY OF THE INVENTION <EOH>It is an object of this invention to avoid or alleviate the problems of the prior art. It is also an object of this invention to provide a cemented carbide body having high wear resistance. It is a specific object of the present invention to provide a metal drilling tool with increased tool life in applications requiring good wear resistance. In one aspect of the invention, there is provided a cemented carbide body of the following composition: Co: from about 10-12 wt-%, TaC: <3 wt-%, NbC: from about 1.5-5.5 wt-%, TiC: from about 3-5 wt-% and WC: as remainder. In another aspect of the invention, there is provided the use of the above-defined body as a rotary tool for metal machining. | 20050126 | 20071120 | 20050929 | 78958.0 | 0 | MAI, NGOCLAN THI | CEMENTED CARBIDE BODY | UNDISCOUNTED | 0 | ACCEPTED | 2,005 |
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11,042,327 | ACCEPTED | Apparatus and method for providing a workspace | A portable and wall mountable apparatus comprising a flexible case having one or more internal compartments for removably receiving stiffeners to thereby form a pair of panels. The panels are pivotally joined and fold shut against each other to form a portable carrier for articles such as architectural plans and the like. Handles are attached to the flexible case to facilitate transport. A plurality of tabs with grommets are attached to the flexible case to allow the panels to be removably mounted to a wall such that one of the panels may be used as a desktop or workspace. One or more restraining devices suspend the panel being used as a desktop or workplace in a horizontal position when the case is mounted to a wall. The flexible case may also be conveniently stored by removing the stiffeners when not in use and rolling up the shell into a compact shape. | 1. An apparatus for providing a workspace, the apparatus comprising: a flexible material having a first portion, the first portion being configured and arranged to enclose a stiffener beneath a workspace section of said material to thereby stiffen said workspace section; and means for suspending the workspace section in an elevated, lateral orientation. 2. The apparatus of claim 1 wherein the flexible material further comprises a second portion, the second portion being configured and arranged to enclose a stiffener beneath a panel section of said material to thereby stiffen said panel section. 3. The apparatus of claim 2 wherein the workspace section and the panel section are disposed in a pivotal relationship with respect to each other. 4. The apparatus of claim 3 wherein the flexible case further comprises at least one opening for inserting and removing the stiffeners. 5. The apparatus of claim 1 wherein the flexible case further comprises at least one opening for inserting and removing the stiffener. 6. The apparatus of claim 1 wherein the means for suspending the workspace section comprises a pair of flexible restraining members and at least one fastener device connected to the flexible case for removably mounting the flexible case to a structure. 7. The apparatus of claim 1 further comprising a means for securing the workspace section in a vertical orientation. 8. The apparatus of claim 1 wherein the workspace section terminates in a proximal free edge. 9. The apparatus of claim 1 wherein the means for suspending the workspace section is operable to suspend the workspace section in a substantially horizontal orientation. 10. An apparatus for providing a portable and wall mountable workspace, the apparatus comprising: a flexible case having a first portion, the first portion being configured and arranged to enclose a stiffener beneath a workspace section of said material to thereby stiffen said workspace section; at least one fastener device connected to the flexible case for removably mounting the flexible case to a structure; and at least one restraining device operable to support the first portion of the flexible case in an elevated, lateral orientation when said flexible case is mounted to a structure. 11. The apparatus of claim 10 wherein the flexible case further comprises an opening for inserting and removing the stiffener. 12. The apparatus of claim 10 wherein the at least one restraining device is formed of a flexible material. 13. The apparatus of claim 12 wherein the at least one restraining device comprises two restraining devices disposed proximate opposing ends of the first portion, each of the retraining devices being substantially triangular in shape. 14. The apparatus of claim 10 wherein the at least one fastener comprises a plurality of tabbed portions. 15. The apparatus of claim 14 wherein the tabbed portions are spaced about sixteen (16) inches (0.41 meters) apart. 16. The apparatus of claim 10 further comprising a plurality of storage pockets attached to the flexible case. 17. The apparatus of claim 10 further comprising a handle connected to the flexible case. 18. The apparatus of claim 10 wherein the workspace section is pivotally operable between an open position and a closed position. 19. The apparatus of claim 18 further comprising a fastener for securing the workspace section in the closed position. 20. The apparatus of claim 19 wherein the fastener comprises a flap removably securable to the workspace section. 21. The apparatus of claim 10 wherein the flexible case is collapsible into a rolled up position when the stiffener is removed from the flexible case. 22. The apparatus of claim 10 wherein the flexible case is formed of a waterproof material. 23. An apparatus for providing a wall mountable workspace, the apparatus comprising: a flexible case including a pair of rigid panels, the pair of rigid panels being pivotally interconnected such that the panels are operable to move between an open position and a closed position; at least one fastener connected to the flexible case for removably mounting the flexible case to a structure; and at least one restraining device operable to suspend one of the rigid panels in a substantially horizontal position when said flexible case is mounted to a structure to thereby allow the suspended rigid panel to function as a workspace. 24. The apparatus of claim 23 wherein each of the rigid panels comprises a stiffener. 25. The apparatus of claim 24 further comprising at least one opening in the flexible case for removing the stiffeners from each of the rigid panels. 26. The apparatus of claim 23 wherein the at least one restraining device is formed of a flexible material. 27. The apparatus of claim 23 wherein the at least one fastener comprises a plurality of tabbed portions connected to the flexible case. 28. The apparatus of claim 23 further comprising a handle connected to the flexible case. 29. The apparatus of claim 23 further comprising a plurality of storage pockets disposed on the flexible case. 30. The apparatus of claim 23 wherein the flexible case is collapsible into a rolled up position. 31. The apparatus of claim 23 further comprising a fastener for releasably securing the pair of panels in the closed position. 32. The apparatus of claim 31 wherein the fastener comprises a flap. 33. An apparatus for providing a portable workspace, the apparatus comprising: a flexible case having a workspace section and at least one internal compartment; one or more openings in the flexible case, the one or more openings selectively permitting stiffeners to be inserted into and removed from the at least one internal compartment; and at least one fastener connected to the flexible case for removably mounting the flexible case to a support such that the workspace section may be suspended in an elevated, lateral orientation. 34. The apparatus of claim 33 wherein the at least one internal compartment is configured and dimensioned for removably receiving a stiffener that is substantially rectangular in shape. 35. The apparatus of claim 33 wherein the at least one internal compartment is configured and dimensioned for removably receiving a piece of wood. 36. The apparatus of claim 33 further comprising at least one restraining device for maintaining the workspace section in a substantially horizontal orientation. 37. The apparatus of claim 36 wherein the at least one restraining device is formed of a flexible material that is substantially triangular in shape. 38. The apparatus of claim 36 wherein the at least one restraining device comprises two restraining devices connected proximate opposing ends of the at least one internal compartment. 39. The apparatus of claim 33 wherein the at least one fastener comprises a plurality of tabbed portions that are each spaced about sixteen (16) inches (0.41 meters) apart. 40. The apparatus of claim 33 further comprising a handle connected to the flexible case. 41. The apparatus of claim 33 further comprising a plurality of storage pockets disposed on the flexible case. 42. The apparatus of claim 33 wherein the flexible case is formed of a waterproof material. 43. An apparatus for providing a wall mountable workspace, the apparatus comprising: a flexible case having a pair of panels pivotably moveable between an open position and a closed position; and at least one fastener connected to the flexible case for removably mounting the flexible case to a support; wherein one of the panels functions as the workspace when said flexible case is mounted on a support and when the panels are in the open position and wherein the panels form a space for storage between each other when the panels are in the closed position. 44. The apparatus of claim 43 wherein each of the panels comprises a removable stiffener. 45. The apparatus of claim 44 further comprising one or more openings in the flexible case, the one or more openings selectively permitting insertion and removal of the stiffeners. 46. The apparatus of claim 43 further comprising an internal compartment located inside each panel. 47. The apparatus of claim 43 further comprising at least one restraining device to prevent the panels from pivotally moving more than about 90 degrees apart. 48. The apparatus of claim 47 wherein the at least one restraining device is formed from a flexible material of having a triangular shape. 49. The apparatus of claim 47 wherein the at least one restraining device folds to fit between the pair of panels when the panels are in the closed position. 50. The apparatus of claim 43 further comprising a handle coupled to the flexible case. 51. The apparatus of claim 43 wherein the at least one fastener comprises a plurality of tabbed portions. 52. The apparatus of claim 43 further comprising a plurality of storage pockets disposed on the flexible case. 53. The apparatus of claim 43 wherein the flexible case is formed of a waterproof material. 54. An apparatus for providing a portable and wall mountable workspace, the apparatus comprising: a flexible case having a pair of panels joined in a pivotal relationship to thereby allow the panels to be pivotally moveable between an open position and a closed position; a pair of internal compartments, one of the compartments located in each of the panels; a pair of openings on the flexible case, the pair of openings selectively permitting stiffeners to be inserted and removed from the internal compartments; a plurality of fasteners coupled to the flexible case for removably mounting the flexible case to a structure, the plurality of fasteners comprising a plurality of tabbed portions spaced about sixteen (16) inches (0.41 meters) apart; at least one handle connected to the flexible case; one or more storage pockets on the flexible case; a flap connected to one of the panels, the flap being operable to temporarily secure the panels in the closed position; and a pair of flexible restraining devices for maintaining one of the panels in a substantially horizontal position when the flexible case is mounted to a structure to thereby form a work area, each of the flexible restraining devices being substantially triangular in shape; wherein the flexible case is collapsible into a compact position when the stiffeners are removed from the internal compartments. 55. A method for providing a wall mountable workspace, the method comprising the steps of: providing a flexible case having at least one internal compartment and at least one fastening device for removably mounting the flexible case to a structure; inserting a first stiffener into one of the internal compartments in the flexible case; and mounting the flexible case to a structure such that a portion of the flexible case is disposed in an elevated, lateral orientation to thereby function as the workspace. 56. The method of claim 55 wherein the flexible case is formed of a waterproof material. 57. The method of claim 55 wherein the flexible case further comprises one or more storage pockets. 58. The method of claim 55 wherein the flexible case further comprises a handle. 59. The method of claim 55 further comprising the steps of removing the first stiffener from the internal compartment and rolling the flexible case into a compact storage position. 60. The method of claim 55 further comprising the step of inserting a second stiffener into another of the internal compartments. 61. The method of claim 55 wherein the stiffener is a piece of plywood. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of co-pending U.S. patent application Ser. No. ______ (yet to be assigned), filed Jan. 21, 2005, entitled “Apparatus and Method for Providing a Workspace,” which is hereby incorporated by reference herein in its entirety, including but not limited to those portions that specifically appear hereinafter, the incorporation by reference being made with the following exception: In the event that any portion of the above-referenced application is inconsistent with this application, this application supercedes said above-referenced application. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable. BACKGROUND 1. The Field of the Invention The present disclosure relates generally to portable workbenches and desks, and more particularly, but not necessarily entirely, to a portable workspace, one version of which is wall-mountable and formed of a flexible outer material capable of providing a combination workspace and carrier. 2. Description of Related Art Portable tables and workbenches are well known and popular devices for conveniently providing a workspace at a desired location. These devices typically comprise one or more pair of collapsible legs attached to a top. While useful for there intended purposes, these devices often prove unsatisfactory in certain settings. Principally, these devices are known to be in some instances cumbersome and unmanageable both in transport and storage. For example, these devices are usually not transportable in a standard sized car but instead require a truck or a trailer. Even when a truck or a trailer is available, the devices may occupy too much space if other items are being transported as well. Examples of previously available portable tables and workbenches are found in the following references. U.S. Pat. No. 6,289,824 (granted Sep. 18, 2001 to Parker et al.) discloses a collapsible jobsite plan table that is collapsible and adjustable and that is made of plastic or other lightweight material. U.S. Pat. No. 5,281,019 (granted Jan. 25, 1994 to Rodeck) discloses a foldable plan stand case having detachable legs for supporting the case in the open position. U.S. Pat. No. 5,067,417 (granted Nov. 26, 1991 to Marmentini et al.) discloses a foldable table including to half sections pivotally joined together. Another disadvantage to portable tables and workbenches is that they are often not suitable for use at certain locations, such as a construction job site. This is due to the fact that if a dedicated space for these devices is not available, they are often in the way and must constantly be moved or taken down in order to not interfere with construction. Another drawback to portable tables and workbenches is that they generally do not provide a storage area when collapsed or during transport. It would be useful to provide a storage area for articles such that Other previously known devices for providing a workspace include wall mountable devices having a fold down table which may be opened to a horizontal position for use or closed to a vertical position when not in use. These wall mountable device may include interior storage compartments and the like. These wall mountable devices are generally constructed using a box and frame construction that results in only a slight improvement, if any, over the convenience of standard portable tables and workbenches. In particular, the materials and construction of known wall mountable devices may actually make them heavier and more cumbersome than portable tables and workbenches. Examples of previously available wall mountable devices are found in the following references. U.S. Pat. No. 6,039,416 (granted Mar. 21, 2000 to Lambert) discloses a pivotal work bench assembly that is mountable on a wall and that includes pivotal and lockable legs. U.S. Pat. No. 5,513,574 (granted May 7, 1996 to Collins) discloses a wall mountable folding table apparatus which is contained in a cabinet having a pair of folding doors into which the table is folded and stored. U.S. Pat. No. 4,919,498 (granted Apr. 24, 1990 to Turner) discloses a portable and wall mountable desk including extendable legs. The previously available devices are thus characterized by several disadvantages that are addressed by the present disclosure. The present disclosure minimizes, and in some aspects eliminates, the above-mentioned failures, and other problems, by utilizing the methods and structural features described herein. The features and advantages of the disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the disclosure without undue experimentation. The features and advantages of the disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the disclosure will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings in which: FIG. 1 is a perspective view of one exemplary embodiment of the present disclosure mounted on a wall and in an open position. FIG. 1A is a perspective view of an alternative embodiment of the embodiment of FIG. 1, showing a wall-mounted portable workspace having front legs. FIG. 2 is a perspective view of the exemplary embodiment shown in FIG. 1 mounted on a wall in a closed or upright position. FIG. 3 is a perspective view of the exemplary embodiment shown in FIG. 1 in a closed. FIG. 4 is a perspective view of the exemplary embodiment shown in FIG. 1 illustrating the removable stiffeners. FIG. 5 is a perspective view of the exemplary embodiment shown in FIG. 1 in a rolled up position. FIG. 6 is a cross-sectional view of pivotally interconnected panels. FIG. 7 is a perspective view of an alternative embodiment of the embodiment of FIGS. 1 and 1A, showing a free-standing workspace having rear legs and front legs. DETAILED DESCRIPTION For the purposes of promoting an understanding of the principles in accordance with the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the disclosure as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the disclosure claimed. It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. In describing and claiming the present disclosure, the following terminology will be used in accordance with the definitions set out below. As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps. Applicant has discovered a multi-purpose apparatus that provides an instant and efficient place to work at a job site, a home workshop or any other desirable location. The apparatus may also function as a document carrier similar to an artist portfolio. Applicant's apparatus may comprise a flexible case formed of a light weight and thin material. A pair of internal compartments may be formed within the flexible case to receive a pair of stiffeners, such as plywood, to form an internal support structure for the apparatus. In particular, the pair of stiffeners may form a pair of panels that are operable between an open position and a closed position. While the outer case is mounted on a wall, one of the panels may function as a work area or desk top. In addition, storage pockets allow various items to be easily stored. In the closed position, an inside face of each of the pair of panels may jointly form a storage area for items such as architectural plans and the like. A handle attached to the flexible case may also allow the entire apparatus to function as a document carrier while the panels are in the closed position. Advantageously, the pair of stiffeners may be removed to thereby allow the flexible case to be easily transported and stored by collapsing and rolling up the case to a compact size. Referring now to FIG. 1, there is shown a perspective view of a portable and wall mountable apparatus 10 in accordance with one exemplary embodiment of the present disclosure. The apparatus 10 is shown in an open position, and may be mounted as shown to an unfinished or framed wall comprising a plurality of vertically extending studs having reference numerals 12 through 18. It should be understood, however, that the apparatus 10 may be mounted to any type of structure. The apparatus 10 includes a flexible case formed by a pair of panels 18 and 20 pivotally interconnected such that the panels 18 and 20 may be moveable between an open position and a closed position. As shown FIG. 1, the panel 20 may be opened to a substantially horizontal position such that its inside face 24 may function as a work area, workbench or desk top. The inside face 24 may be referred to herein as a “workspace section,” the term “workspace section” meaning a space in which all portions of the workspace are disposed in a fixed orientation relative to each other, though the workspace section itself may be moveable relative to others parts of the apparatus 10. The panel 18 is shown mounted in a vertical position and adjacent to studs 12 through 18 such that its inside face 22 may serve as a back to the work area provided by the inside face 24 of the panel 20. The panels 18 and 20 may be sized and shaped to any size depending upon the needs of the user. The panels 18 and 20, for example, may vary between about three (3) to eight (8) feet (0.91 meters to 2.4 meters) long, and about two (2) to five (5) feet (0.61 meters to 1.5 meters) wide. The panels 18 and 20 may formed in a generally rectangular shape. The panel 18 further comprises an outermost edge 26 and an innermost edge 28 and two opposing side edges 30 and 32. The panel 20 also further comprises an outermost edge 34 and an innermost edge 36 and two opposing side edges 38 and 40. As previously mentioned, the panel 18 and the panel 20 are pivotally interconnected along their respective innermost edges 28 and 36. Due to the pivotal relationship between panels 18 and 20, a pair of retraining devices 42 and 44 may be employed to suspend and maintain the panel 20 in an elevated and lateral orientation or a substantially horizontal orientation against the force of gravity. Without the restraining devices 42 and 44, the result may be undesirable as the panels 18 and 20 would open without restriction to 180 degrees with respect to each other. A cross-sectional view of the pivotal interconnection of the panels 18 and 20 is shown in FIG. 6. The panel 18 comprises a flexible outer shell 120 enclosing a stiffener 104. The stiffener 104 may either be removable, or non-removable if its encapsulating shell 120 is sewn shut or otherwise sealed to block removed of said stiffener 104. The panel 20 also comprises a flexible outer shell 122 enclosing a stiffener 106. The stiffener 106 may also be removable or non-removable. The flexible outer shells 120 and 122 of the panels 18 and 20, respectively, are interconnected by a flexible bridge portion 124. The bridge portion 124 may also be formed of a flexible material to thereby allow the panels 18 and 20 to pivot or swing with respect to each other as shown by the line indicated with the reference numeral 126. Notably the bridge 124 and the flexible outer shells 120 and 122 may all be made of the same material. The restraining devices 42 and 44 may each be substantially triangular in shape and formed of a flexible material. The restraining device 42 may include a first edge 46 attached to the side edge 32 of the panel 18 and a second edge 48 attached to the side edge 40 of the panel 20. The first edge 46 and the second edge 48 may intersect to form a right angle near the pivotal interconnection between the panels 18 and 20. A third edge 50 of restraining device 42 may extend from the outermost edge 26 of the panel 18 to the outermost edge 34 of the panel 20. Likewise, the restraining device 44 may include a first edge 52 attached to the side edge 30 of the panel 18 and a second edge 54 attached to the side edge 38 of the panel 20. The first edge 52 and the second edge 54 may intersect to form a right angle near the pivotal interconnection between the panels 18 and 20. A third edge 56 of the restraining device 44 may extend from the outermost edge 26 of the panel 18 to the outermost edge 34 of the panel 20. It will be appreciated by those skilled in the art that other types of restraining devices may be used with the present disclosure to support the weight of one of the panels. For example, one or more tethers could be employed to support one of the panels in a substantially horizontal position. In addition, a brace formed from a rigid material such as wood or metal could also be employed to hold one of the panels in a substantially horizontal position. In addition, the pivotal interconnection between the panels 18 and 20 could incorporate a restraining device to stop movement of the panels at about 90 degrees with respect to each other. Also, any type of restraining device anchored to a fixed point and supporting the weight of one of the panels, either separately or in combination with another device, should be considered within the scope of the present disclosure. It will be further appreciated that the present disclosure may not require the use of legs to support one of the panels in a substantially horizontal position. The use of restraining devices to suspend one of the panels from a wall in a substantially horizontal position is a primary feature of the present invention. However, it must be noted that the use of legs to hold one of the panels in a substantially horizontal position is not outside the scope of the present disclosure. Referring now to FIG. 4, each of the panels 18 and 20 may include a pair of internal compartments 100 and 102 enclosing the pair of stiffeners 104 and 106, respectively. As used herein, the term “enclosed” means to cover or encapsulate either partially or entirely one of the stiffeners. A pair of openings 108 and 110 may allow the stiffeners 104 and 106 to be selectively inserted and removed from the compartments 104 and 106, respectively. The opening 108 may or may not include a closure device 112, such as a zipper, for closing the opening 108 and preventing the accidental removal of the stiffener 104. Likewise, the opening 110 may also include a closure device 114, such as a zipper, for closing the opening 110 and preventing the accidental removal of the stiffener 106. Other closure devices may include, without limitation, velcro strips, snaps, buttons, and other similar devices. Thus, it will be appreciated that the closure devices 112 and 114 may include any type of closure device now known or known in the future by those skilled in the art. The internal compartment 100 is located within panel 18 and the internal compartment 102 is located within panel 20. The internal compartments 100 and 102 are approximately the same size as panels 18 and 20, respectively. The stiffeners 104 and 106 provide an internal support for panels 18 and 20. Without the stiffeners 104 and 106, the panels 18 and 20, respectively, would be flaccid and unable to function as described above. This result is due to the flexible nature of the outer shells 120 and 122. It should be noted that the stiffeners 104 and 106 may be permanently installed into their respective internal compartments 100 and 102 or they may be temporarily installed; both cases which fall within the scope of the present disclosure. In one desired embodiment, an apparatus produced pursuant to the present disclosure is produced and sold without any stiffeners for the panels. A user may then provide and install the stiffeners when needed. This may include having the user cut a piece of ⅝ inch (0.59 centimeters) plywood or similar material to form the stiffeners 104 and 106. The foregoing feature is beneficial for several reasons. First, the manufacturer is not burdened with the costs and size associated with producing the stiffeners thereby allowing an apparatus conforming to the present disclosure to be marketed in a more compact and less costly manner. Next, the user may insert the stiffeners on-site thereby reducing the transport and storage space to the use when not in use. Further, since material required for the rigid panels, namely plywood, is readily available at most job sites the user may acquire and discard the stiffeners as needed. It should also be noted that other materials of both a rigid and semi-rigid nature may be used, including all manufactured materials such as plastic. Referring back to FIG. 1, a plurality of storage pockets 58 may be disposed on the inside face 22 of the panel 18. The storage pockets 58 allow useful items such as business cards, cell phones, pens, tools, pencils and other supplies to be conveniently stored and transported. The storage pockets 58 may be formed of a flexible material such as an elastic mesh material and may be positioned in any convenient location on the inside face 22 of panel 18. A drink holder 59 may also be provided for soda pop cans or refillable mugs. The drink holder 59 may be formed of an elastic and flexible material. A plurality of fasteners may be disposed along the outermost edge 26 of the panel 18 for removably mounting the apparatus 10 to a wall. The fasteners may each comprise a tabbed portion 60 having hole 61 which may be reinforced by a grommet. The fasteners may be spaced about sixteen (16) inches (0.41 meters) apart to correspond to the typical spacing of studs 12 through 18 found at a normal construction site. It is to be understood, however, that the spacing between studs may vary significantly, and the fasteners may be positioned to accommodate other configurations. A cross piece (not shown) may be attached horizontally across non-conforming studs to provide points of attachments for the fasteners. The apparatus 10 may be mounted by installing the holes 61 in each of the tabbed portions 60 over nails 62 previously driven into each of the studs 12 through 18. The apparatus 10 may be removed from the wall by simply removing the tabbed portions 60 from the nails 62. It will be appreciated by those skilled in the art that any type of fasteners now known or known in the future may be employed to mount an apparatus pursuant to the present disclosure to a wall. Further, it should be understood that the fasteners may be employed singly or multiply to accomplish the function of mounting an apparatus pursuant to the present disclosure to a wall. It should also be noted that the fasteners may permanently or temporarily mount an apparatus pursuant to the present disclosure to a wall depending upon the needs of a user. Referring now to FIGS. 2 and 3, there is shown the apparatus 10 having the panels 18 and 20 in a closed or upright position. As discussed above, the panels 18 and 20 are pivotally interconnected along their respective innermost edges 28 and 26. As can be observed, in a closed or upright position, the inside faces 22 and 24 of the panels 18 and 20, respectively, are pivotally swung into close proximity. A flap 64 affixed to the outside face (not explicitly shown) of panel 18 is folded over the outermost edges 26 and 34 of panels 18 and 20, respectively, and secured to the outside face 63 of the panel 20. As best seen in FIG. 3, a velcro strip 68 attached to an inside surface 65 of flap 64 mates with a corresponding velcro strip 66 attached to the outside face 63 of the panel 20 in order to secure the panels 18 and 20 in the closed or upright position. The flap 64 may be formed of a flexible material. It will be appreciated that the structure and apparatus disclosed herein is merely one example of a means for securing the workspace section in a vertical orientation, and it should be appreciated that any structure, apparatus or system for a securing the workspace section in a vertical orientation which performs functions the same as, or equivalent to, those disclosed herein are intended to fall within the scope of a means for securing the workspace section in a vertical orientation, including those structures,. apparatus or systems for securing the workspace section in a vertical orientation which are presently known, or which may become available in the future. Anything which functions the same as, or equivalently to, a means for securing the workspace section in a vertical orientation falls within the scope of this element. Referring now to FIG. 1A, there is shown an alternative embodiment to the apparatus 10 of FIG. 1, designed generally in FIG. 1A as item 10a. A principal difference between the apparatus 10 of FIG. 1, and the apparatus 10a of FIG. 1A, is the addition of front legs 19 in apparatus 10a. Legs 19 may be attached beneath front corner sections 21 of panel 20, in any suitable fixed or releasable manner desired and known. The addition of legs 19 entirely optional, and is not required. As seen in FIG. 2, advantageously, the panel 20 may be closed while the apparatus 10 is still mounted to the studs 14 through 18. It may be necessary, however, to unhook the middle tabbed portions 60 from the nails 62 on studs 14 and 16 to thereby enable the flap 64 to be employed to secure the panels 18 and 20 in the closed or upright position. So engaged, the flap 64 may prevent water and other undesirable material from entering between the panels 18 and 20, especially during inclement weather common at job sites. It should be understood by those skilled in the art that it is within the scope of the present disclosure that other devices and structure now known or known in the future may be used to secure, fasten or maintain the panels 18 and 20 in a closed or upright position. These other devices and structure, may include, without limitation, straps, latches, snaps, zippers, clips, velcro, elastic cords, cinch straps and the like. Indeed, any suitable closure device, consistent with maintaining the features described herein, may be used to secure the panels 18 and 20 in a closed position. As seen in FIG. 3, a pair of handles 70 may allow the apparatus 10 to function as a portable document carrier when the apparatus 10 is removed from the studs 12 through 18. In that regard, it will be noted that a pocket may be formed between the panels 18 and 20 while they are in the closed or upright position. This pocket will allow items such as architectural plans and the like to be protected during transport. The handles 70 may be formed of nylon straps or any other suitable material. The handles 70 may be connected to flexible outer shells 120 and 122 of the panels 18 and 20. When the panels 18 and 20 of the apparatus 10 are in the closed or upright position, the restraining devices 42 and 44 fold neatly into the area between the panels 18 and 20 due to their flexible nature. In this manner, the restraining devices 42 and 44 are conveniently stored in an out of the way location. Further, the folded up restraining device 42 and 44 prevent water and other debris from entering between the panels 18 and 20. When the panels 18 and 20 are opened, the restraining devices 42 and 44 deploy to thereby suspend the panel 20 in a substantially horizontal position. With the stiffeners 104 and 106 installed into the internal compartments 100 and 102, respectively, the apparatus 10 may be employed as discussed above, including mounting the apparatus 10 on a wall as shown in FIGS. 1 and 2, or the apparatus 10 may be used as a portable document carrier as shown in FIG. 3. When the stiffeners 104 and 106 are removed from the internal compartments 100 and 102, respectively, the apparatus 10 may be rolled up into a compact position as shown in FIG. 5. While in the compact position, the apparatus 10 may be easily transported or stored until needed. As detailed above, many of the features of the present disclosure incorporate the use of a flexible material. This flexible material may include a flexible material that is waterproof or water resistant. Further, the flexible material may include any type of manufactured fiber, fabric, cloth, nylon, polyethylene, and canvass. In one exemplary embodiment, the flexible material may include Cordova or any other light weight and durable material. In accordance with the features and combinations described above, a useful method of providing a portable workspace includes the steps of: (1) providing a flexible case having at least one internal compartment and at least one fastening device for removably mounting the flexible case to a structure; (2) inserting a first stiffener into one of the internal compartments in the flexible case; (3) mounting the flexible case to a structure; and (4) opening the flexible case such that the internal compartment containing the first stiffener may function as a workspace section. Those having ordinary skill in the relevant art will appreciate the advantages provide by the features of the present disclosure. For example, it is a feature of the present disclosure to provide a portable apparatus and method for providing a workspace. Another feature of the present disclosure is to provide such a flexible case having internal compartments for removably receiving a pair of stiffeners. It is a further feature of the present disclosure, in accordance with one aspect thereof, to provide an apparatus that may function as both a wall mountable workspace and a portable document carrier. Referring now to FIG. 7, there is shown another alternative embodiment to the apparatus 10 of FIG. 1 and the apparatus 10a of FIG. 1A, designed generally in FIG. 7 as item 10b. A principal difference in the apparatus 10b of FIG. 7 is that it is a free-standing apparatus, including the addition of front legs 19, as well as rear legs 23. Tabbed portions 60 may simply be placed over a nail 62 or other projection fastened to rear legs 23, to support a rear section of the apparatus 10b. Any other suitable means for supporting the apparatus 10b in an elevated position, whether by utilizing rear legs 23 or some other version of rear legs not shown herein, may be utilized. Front legs 19 may be attached beneath front corner sections 21 of panel 20, in any suitable fixed or releasable manner desired and known. The use of rear legs 23 or other suitable support, instead of studs 12, 14, 16 and 18 of FIG. 1, is entirely optional, and is not required. The use of front legs 19 is also entirely optional, and is not required. It will be appreciated that the structure and apparatus disclosed herein are merely some examples of means for suspending the workspace section in an elevated, lateral orientation, and it should be appreciated that any structure, apparatus or system for suspending the workspace section in an elevated, lateral orientation which performs functions the same as, or equivalent to, those disclosed herein are intended to fall within the scope of a means for suspending the workspace section in an elevated, lateral orientation, including those structures, apparatus or systems for suspending the workspace section in an elevated, lateral orientation which are presently known, or which may become available in the future. Anything which functions the same as, or equivalently to, a means for suspending the workspace section in an elevated, lateral orientation falls within the scope of this element. In the foregoing Detailed Description, various features of the present disclosure are grouped together in multiple embodiments. This disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of any of the foregoing disclosed embodiments. Thus, the following claims are hereby incorporated into this Detailed Description of the Disclosure by this reference, with each claim standing on its own as a separate embodiment of the present disclosure. It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present disclosure. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present disclosure and the appended claims are intended to cover such modifications and arrangements. Thus, while the present disclosure has been shown in the drawings and described above with particularity and detail, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, variations in size, materials, shape, form, function and manner of operation, assembly and use may be made without departing from the principles and concepts set forth herein. | <SOH> BACKGROUND <EOH>1. The Field of the Invention The present disclosure relates generally to portable workbenches and desks, and more particularly, but not necessarily entirely, to a portable workspace, one version of which is wall-mountable and formed of a flexible outer material capable of providing a combination workspace and carrier. 2. Description of Related Art Portable tables and workbenches are well known and popular devices for conveniently providing a workspace at a desired location. These devices typically comprise one or more pair of collapsible legs attached to a top. While useful for there intended purposes, these devices often prove unsatisfactory in certain settings. Principally, these devices are known to be in some instances cumbersome and unmanageable both in transport and storage. For example, these devices are usually not transportable in a standard sized car but instead require a truck or a trailer. Even when a truck or a trailer is available, the devices may occupy too much space if other items are being transported as well. Examples of previously available portable tables and workbenches are found in the following references. U.S. Pat. No. 6,289,824 (granted Sep. 18, 2001 to Parker et al.) discloses a collapsible jobsite plan table that is collapsible and adjustable and that is made of plastic or other lightweight material. U.S. Pat. No. 5,281,019 (granted Jan. 25, 1994 to Rodeck) discloses a foldable plan stand case having detachable legs for supporting the case in the open position. U.S. Pat. No. 5,067,417 (granted Nov. 26, 1991 to Marmentini et al.) discloses a foldable table including to half sections pivotally joined together. Another disadvantage to portable tables and workbenches is that they are often not suitable for use at certain locations, such as a construction job site. This is due to the fact that if a dedicated space for these devices is not available, they are often in the way and must constantly be moved or taken down in order to not interfere with construction. Another drawback to portable tables and workbenches is that they generally do not provide a storage area when collapsed or during transport. It would be useful to provide a storage area for articles such that Other previously known devices for providing a workspace include wall mountable devices having a fold down table which may be opened to a horizontal position for use or closed to a vertical position when not in use. These wall mountable device may include interior storage compartments and the like. These wall mountable devices are generally constructed using a box and frame construction that results in only a slight improvement, if any, over the convenience of standard portable tables and workbenches. In particular, the materials and construction of known wall mountable devices may actually make them heavier and more cumbersome than portable tables and workbenches. Examples of previously available wall mountable devices are found in the following references. U.S. Pat. No. 6,039,416 (granted Mar. 21, 2000 to Lambert) discloses a pivotal work bench assembly that is mountable on a wall and that includes pivotal and lockable legs. U.S. Pat. No. 5,513,574 (granted May 7, 1996 to Collins) discloses a wall mountable folding table apparatus which is contained in a cabinet having a pair of folding doors into which the table is folded and stored. U.S. Pat. No. 4,919,498 (granted Apr. 24, 1990 to Turner) discloses a portable and wall mountable desk including extendable legs. The previously available devices are thus characterized by several disadvantages that are addressed by the present disclosure. The present disclosure minimizes, and in some aspects eliminates, the above-mentioned failures, and other problems, by utilizing the methods and structural features described herein. The features and advantages of the disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the disclosure without undue experimentation. The features and advantages of the disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. | <SOH> BRIEF DESCRIPTION OF THE DRAWINGS <EOH>The features and advantages of the disclosure will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings in which: FIG. 1 is a perspective view of one exemplary embodiment of the present disclosure mounted on a wall and in an open position. FIG. 1A is a perspective view of an alternative embodiment of the embodiment of FIG. 1 , showing a wall-mounted portable workspace having front legs. FIG. 2 is a perspective view of the exemplary embodiment shown in FIG. 1 mounted on a wall in a closed or upright position. FIG. 3 is a perspective view of the exemplary embodiment shown in FIG. 1 in a closed. FIG. 4 is a perspective view of the exemplary embodiment shown in FIG. 1 illustrating the removable stiffeners. FIG. 5 is a perspective view of the exemplary embodiment shown in FIG. 1 in a rolled up position. FIG. 6 is a cross-sectional view of pivotally interconnected panels. FIG. 7 is a perspective view of an alternative embodiment of the embodiment of FIGS. 1 and 1 A, showing a free-standing workspace having rear legs and front legs. detailed-description description="Detailed Description" end="lead"? | 20050124 | 20080909 | 20060727 | 64229.0 | A47B2300 | 0 | WILKENS, JANET MARIE | APPARATUS AND METHOD FOR PROVIDING A WORKSPACE | SMALL | 1 | CONT-ACCEPTED | A47B | 2,005 |
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11,042,350 | ACCEPTED | Halogenated solvent remediation | Methods for enhancing bioremediation of ground water contaminated with nonaqueous halogenated solvents are disclosed. An illustrative method includes adding a composition to the ground water wherein the composition is an electron donor for microbe-mediated reductive dehalogenation of the halogenated solvents and enhances mass transfer of the halogenated solvents from residual source areas into the aqueous phase of the ground water. Illustrative compositions effective in these methods include whey powder, liquid whey, and mixtures of ethyl lactate and C2 or higher carboxylic acids or hydroxy acids, salts thereof, esters thereof, or mixtures thereof. | 1. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein said electron donor comprises an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey. 2. The method of claim 1 wherein said microbe is indigenous to the ground water. 3. The method of claim 1 further comprising adding the halo-respiring microbe to the ground water. 4. The method of claim 1 wherein the halo-respiring microbe is a chloro-respiring microbe. 5. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein said electron donor comprises a mixture of (a) at least about 0.5% by weight of ethyl lactate and (b) at least about 0.5% by weight of a C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. 6. The method of claim 5 wherein the C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof comprises a mixture of propionic acid and sodium propionate. 7. The method of claim 5 wherein said microbe is indigenous to the ground water. 8. The method of claim 5 further comprising adding the halo-respiring microbe to the ground water. 9. A method for enhancing mass transfer of a nonaqueous halogenated solvent present in a nonaqueous residual source of contamination in ground water, said ground water comprising an aqueous phase, into said aqueous phase comprising adding to said ground water an effective amount of a composition that donates electrons for microbe-mediated reductive dehalogenation of said nonaqueous halogenated solvent into innocuous compounds and functions as a surfactant or co-solvent for solubilizing said nonaqueous halogenated solvent, wherein said composition comprises (a) an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey, or (b) a mixture of at least about 0.5% by weight of ethyl lactate and at least about 0.5% by weight of a C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. 10. The method of claim 9 wherein the C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof comprises a mixture of propionic acid and sodium propionate. | CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of co-pending U.S. patent application Ser. No. 10/853,899, filed May 25, 2004, entitled “Halogenated Solvent Remediaiton,” which is incorporated herein by reference in its entirety, including but not limited to those portions that specifically appear hereinafter, the incorporation by reference being made with the following exception: In the event that any portion of the above-referenced application is inconsistent with this application, this application supercedes said above-referenced application. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable. BACKGROUND OF THE INVENTION This invention relates to remediation of environmental contamination. More particularly, the invention relates to methods for accelerating or enhancing in situ dehalogenation of nonaqueous halogenated solvents in ground water. These methods involve adding to the contaminated ground water a composition of matter that both functions as an electron donor for halorespiration processes carried out by indigenous or exogenously supplied bacteria, wherein the nonaqueous halogenated solvents are dehalogenated and degraded to innocuous compounds, and promotes mass transfer of the nonaqueous halogenated solvents from a source into the ground water where such solvents can be broken down. For many years little care was taken in the handling of organic solvents and other materials that were used in industry and at government installations, such as military bases. Because of poor handling techniques and, occasionally, intentional dumping, many industrial sites and military bases now have contaminated areas containing relatively high concentrations of these contaminants. Chlorinated solvents, such as trichloroethylene (TCE), perchloroethylene (PCE), and other types of liquids, are common at such sites, and if not removed can infiltrate groundwater supplies, rendering the water unfit for consumption and other uses. A variety of techniques have been used to promote the removal of such chemical contaminants, both from the soil and from the ground water. The principle method of ground water remediation currently used where dense, non-aqueous phase liquids (DNAPLs) are involved is what is commonly referred to as “pump-and-treat” remediation. According to this method, wells are drilled into the contaminated area and contaminated ground water is pumped above the surface, where it is treated to remove the contaminants. The limitations of the pump-and-treat method have been documented in articles such as D. M. Mackay & J. A. Cherry, Groundwater Contamination: Pump and Treat Remediation, 23 Environ. Sci. Technol. 630-636 (1989). The authors of this article concluded that pump-and-treat remediation can only be relied on to contain ground water contamination through the manipulation of hydraulic gradients within an aquifer. The reasons for the failure of the pump-and-treat method to decontaminate aquifers are rooted in the limited aqueous solubility of many DNAPLs in ground water and other processes involving contaminant desorption and diffusion. Because of the low aqueous solubility of most DNAPLs, their removal by ground water extraction requires exceptionally long periods of time. Due to the general impracticability of the pump-and-treat method, considerable attention has been paid recently to other methods for effecting remediation. One such process is commonly referred to as enhanced solubilization. This method uses micellar surfactants to increase the effective solubility of the DNAPLs to accelerate the rate of removal. The mechanism of solubilization displayed by surfactants arises from the formation of microemulsions by the surfactants, water, and the solubilized DNAPLs. For example, Table 1 shows solubilization of PCE by various nonionic and anionic surfactants. These data indicate that even dilute surfactants can significantly increase the aqueous solubility of PCE. TABLE 1 Surfactant Surfactant Concentration PCE Solubilized (mg/l) Water 0% 240 Nonylphenol ethoxylate and 2% 11,700 its phosphate ester (1:1) Sodium diamyl and dioctyl 4% 85,000 sulfosuccinates (1:1) in 500 mg CaCl2/l Nonylphenol ethoxylate 1% 1,300 A serious drawback with the surfactant-enhanced aquifer remediation is that the vertical mobility of the solubilized DNAPLs substantially requires that an aquiclude be present to catch any solubilized contaminant that migrates vertically. Many aquifers, however, lack such an aquiclude. If the traditional surfactant-enhanced aquifer remediation method were to be used with an aquifer lacking an aquiclude, there is a significant risk that the solubilized DNAPLs will spread vertically and contaminate an increasingly large volume. Another drawback of surfactant-enhanced aquifer remediation is the need to pump high concentrations of contaminated water above ground, which results in exposure risks to workers and the environment, and the need to dispose or recycle the surfactant. Another method for effecting remediation of ground water contaminated with DNAPLs is known as enhanced bioremediation. Enhanced bioremediation, as opposed to intrinsic bioremediation, of halogenated solvent-contaminated ground water falls into the two broad categories of aerobic and anaerobic bioremediation. The aerobic processes, regardless of whether they are carried out in situ or in a bioreactor, require addition of (1) oxygen as the electron acceptor for catabolism of the halogenated solvents, and (2) a carbon source, such as methane, propane, phenol, toluene, or butane. The utilization of an appropriate carbon source induces an enzyme that fortuitously degrades many halogenated solvents, but without any immediate benefit to the microorganisms involved. This process has been applied in situ to aqueous contamination in several instances, and at least one patent has been granted for this approach (U.S. Pat. No. 5,384,048). It has also been used to treat aqueous contamination in above-ground bioreactors with numerous variations, especially using proprietary microorganisms and nutrient mixes. Many patents have been granted in this area, e.g., U.S. Pat. No. 5,057,221; U.S. Pat. No. 5,962,305; U.S. Pat. No. 5,945,331. Anaerobic bioremediation of halogenated solvents is a fundamentally different process than aerobic bioremediation. Under appropriate anaerobic conditions, chlorinated solvents can be used directly by some microorganisms as electron acceptors through a process that has come to be known as “chlororespiration,” or, more generally, “halorespiration.” D. L. Freedman & J. M. Gossett, Biological Reductive Dechlorination of Tetrachloroethylene and Trichloroethylene to Ethylene Under Methanogenic Conditions, 55 Applied Environ. Microbiol. 2144-2155 (1989), first published the complete degradation pathway for chlorinated ethenes to ethene. In the following years, several publications reported evidence that the degradation could be achieved through microbial respiration, indicating that the microorganisms could actually grow by using chlorinated solvents directly as electron acceptors. The primary requirement to facilitate this process is the addition of a suitable electron donor or carbon source. Many electron donors have been described in the literature, including acetate, lactate, propionate, butyrate, formate, ethanol, hydrogen, and many others. U.S. Pat. No. 5,277,815 issued in 1994 for in situ electron donor addition along with control of redox conditions to effect the desired end products. U.S. Pat. No. 5,578,210 issued later for enhanced anaerobic in situ bioremediation using “biotransformation enhancing agents,” i.e., electron donors such as propylene glycol, glycerol, glutamate, a mixture of proteose peptone, beef extract, yeast extract, malt extract, dextrose, and ascorbic acid, and mixtures thereof. Based primarily on what was publicly available in the scientific literature, studies of enhanced anaerobic in situ bioremediation of chlorinated solvents began in the mid-1990s. This approach generally includes electron donor addition, sometimes with other micronutrients, to facilitate biotransformation of aqueous-phase contaminants. To date, only a few large-scale studies have been published in the peer-reviewed literature, but environmental consulting companies and remediation contractors are increasingly using the general approach. With one very recent exception, discussed below, all of the work done in this area to date has focused on the biodegradation of aqueous contaminants, because microorganisms cannot directly degrade nonaqueous contaminants. Consequently, bioremediation is not generally thought to be applicable to sites with residual DNAPLs in the subsurface. Therefore, the technologies currently in use include thermal technologies such as steam stripping, in situ chemical oxidation, surfactant flushing, or co-solvent flushing. Surfactant (or co-solvent) flushing, briefly described above, is a chemical process that aims to facilitate transport of nonaqueous contaminants, but without attention to biodegradation. At many sites, however, the pump-and-treat process continues to be used to hydraulically contain residual source areas although it is almost universally accepted that these systems will have to operate in perpetuity because of their inefficient removal of nonaqueous contaminants. The notable recent exception to the focus of bioremediation on aqueous contaminants away from residual source areas is a study by C. S. Carr et al., Effect of Dechlorinating Bacteria on the Longevity and Composition of PCE-Containing Nonaqueous Phase Liquids under Equilibrium Dissolution Conditions, 34 Environ. Sci. Technol. 1088-1094 (2000), demonstrating that anaerobic bioremediation of tetrachloroethene (PCE) enhanced mass transfer from the nonaqueous phase to the aqueous phase and significantly shortened the longevity of the nonaqueous source. The mechanisms identified were (1) enhanced dissolution of PCE resulting from the continuous removal of the compound from the aqueous phase by bacteria, and (2) increased solubility of the intermediate chlorinated ethenes relative to PCE, allowing the total moles of chlorinated ethenes in the aqueous phase to increase due to biotransformation. This study is important because it identifies some of the advantages of enhancing mass transfer from the nonaqueous phase to the aqueous phase. In view of the foregoing, it will be appreciated that providing methods for accelerating or enhancing in situ bioremediation of halogenated solvents in ground water would be a significant advancement in the art. BRIEF SUMMARY OF THE INVENTION It is an advantage of the present invention to provide a method for in situ remediation of DNAPLs in ground water wherein capital costs are low. It is also an advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein mass transfer from the nonaqueous phase to the aqueous phase is enhanced. It is another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the longevity of source areas is shortened. It is still another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein no extraction of contaminated water from the ground is required. It is yet another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water such that the concentrations of the solvents are restored to below regulatory limits and no follow-on remediation activities, other than perhaps monitored natural attenuation, are needed. It is a still further advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the DNAPLs are more rapidly removed from the ground water than with prior art methods and residual source areas are removed. It is another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein transport is facilitated and bioavailability of nonaqueous halogenated solvents is enhanced. It is still another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the method is sustainable for low cost and has low maintenance requirements. It is yet another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water by adding a composition of matter that is both an electron donor and a surfactant or enhancer of mass transfer. It is still further an advantage of the invention to provide a method for remediation of DNAPLs in ground water wherein destruction of the DNAPLs occurs in situ. It is a yet further advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein an unobtrusive appearance is provided and it meets with public acceptance. These and other advantages can be addressed by providing a method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor enhances mass transfer of the nonaqueous halogenated solvents into solution. The electron donor ideally functions as a surfactant or co-solvent. In cases where the electron donor is a functional surfactant, it is typically added at a concentration above the critical micelle concentration in water. In cases where the electron donor is a functional co-solvent, there may be no critical micelle concentration, or if there is a critical micelle concentration in water, the electron donor is usually added at a concentration below such critical micelle concentration. Illustrative electron donors for use in this method include C2-C4 carboxylic acids and hydroxy acids, salts thereof, esters of C2-C4 carboxylic acids and hydroxy acids, and mixtures thereof. In an illustrative embodiment of the invention, the electron donor is a member selected from the group consisting of lactic acid, salts thereof, lactate esters, and mixtures thereof. Illustrative salts of lactic acid include sodium lactate, potassium lactate, lithium lactate, ammonium lactate, calcium lactate, magnesium lactate, manganese lactate, zinc lactate, ferrous lactate, aluminum lactate, and mixtures thereof. Illustrative targets of the method include nonaqueous chlorinated solvents, such as perchloroethylene (PCE), trichloroethylene (TCE), dichloroethylene (DCE), vinyl chloride (VC), 1,1,1-trichloroethane (TCA), carbon tetrachloride and less chlorinated derivatives thereof, and mixtures thereof. An illustrative aspect of the invention relates to enhancing the reductive dehalogenation activity of indigenous halo-respiring microbes present in the ground water. If halo-respiring microbes are absent or ineffective, then such microbes can be exogenously supplied to the ground water. Illustratively, the microbes are bacteria, such as Dehalococcoides ethenogenes strain 195, the Pinellas culture, and the like, and mixtures thereof. The method degrades the halogenated solvents into innocuous compounds such as ethylene, ethane, carbon dioxide, water, halogen salts, and mixtures thereof. A method for enhancing mass transfer of a nonaqueous halogenated solvent present in a nonaqueous residual source of contamination into the aqueous phase comprises adding to the ground water an effective amount of a composition that donates electrons for reductive dehalogenation of the nonaqueous halogenated solvent and functions as a surfactant for solubilizing the nonaqueous halogenated solvent. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprises adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor comprises an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey or derivative thereof. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor comprises a mixture of (a) at least about 0.5% by weight of ethyl lactate and (b) at least about 0.5% by weight of a C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. An illustrative embodiment of such mixture is a mixture of ethyl lactate and dipropionate, wherein dipropionate is a mixture of propionic acid and sodium propionate. A method for enhancing mass transfer of a nonaqueous halogenated solvent present in a nonaqueous residual source of contamination in ground water, the ground water comprising an aqueous phase, into the aqueous phase comprising adding to the ground water an effective amount of a composition that donates electrons for microbe-mediated reductive dehalogenation of the nonaqueous halogenated solvent into innocuous compounds and functions as a surfactant or co-solvent for solubilizing the nonaqueous halogenated solvent, wherein the composition comprises (a) an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey, or (b) a mixture of at least about 0.5% by weight of ethyl lactate and at least about 0.5% by weight of a C2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a site plan of Test Area North showing the locations of injection wells (∘) and monitoring well (●). FIG. 2 is a cross section of Test Area North showing the locations and relative depths of injections wells (open bars), monitoring wells (closed bars), and open or screened intervals (hatched bars). FIGS. 3A-C show the relationship of electron donor concentrations and redox conditions to reductive dechlorination at well TAN-31. FIG. 3A shows COD (solid line) and electron donor (broken line) concentrations in units of mg/L as a function of time in days. FIG. 3B shows ferrous iron (dotted line), sulfate (solid line), and methane (dashed line) concentrations in units of mg/L as a function of time in days. FIG. 3C shows TCE, cis-DCE, trans-DCE, VC, and ethene concentrations in units of μmol/L as a function of time in days. FIG. 4 shows facilitated TCE transport and subsequent biodegradation in well TAN-26. FIG. 5 shows surface tension as a function of lactate concentration for sodium lactate solutions without added ethyl lactate (♦) and with 0.1% ethyl lactate (X), 1% ethyl lactate (⋄), and 10% ethyl lactate (*); error bars represent two standard deviations around the mean. FIG. 6 shows interfacial tension as a function of lactate concentration for sodium lactate solutions without added ethyl lactate (♦) and with 0.1% ethyl lactate (X), 1% ethyl lactate (⋄), and 10% ethyl lactate (*); error bars represent two standard deviations around the mean. FIG. 7 shows correlation between effluent TCE and chemical oxygen demand (COD) for the whey powder column study of Example 3: (♦) tap water TCE, (□) tap water COD influent, () tap water COD, () 1% whey powder TCE, (X) 1% whey powder influent COD, (x) 1% whey powder COD, (▴) 10% whey powder TCE, (◯) 10% whey powder influent COD, (●) 10% whey powder COD. Arrows show when addition of whey powder solution began and ceased. FIG. 8 shows interfacial tension (IFT) measurements between column effluent/influent and TCE DNAPL during the whey powder amendment of Example 3: (♦) tap water, (●) influent whey powder (10%), (▪) whey powder (1%), (◯) influent whey powder (1%), (▴) whey powder (10%), () tap water. Arrows show when addition of whey powder solution began and ceased. FIG. 9 shows correlation between effluent TCE and chemical oxygen demand (COD) for the dipropionate/ethyl lactate amendment of Example 4: (♦) tap water TCE, (▪) tap water influent, (●) 10% ethyl lactate/7% dipropionate COD, () 1% ethyl lactate/0.7% dipropionate TCE, (x) 1% ethyl lactate/0.7% dipropionate COD, (X) 1% ethyl lactate/0.7% dipropionate influent, (●) 10% ethyl lactate/7% dipropionate TCE, () tap water COD, (•) 10% ethyl lactate/7% dipropionate influent. Arrows show when addition of mixtures of ethyl lactate and dipropionate began and ceased. FIG. 10 shows interfacial tension measurements between column effluent/influent and TCE DNAPL during dipropionate/ethyl lactate amendment: (♦) tap water, (▴) 10% ethyl lactate/7% dipropionate, (●) influent 10% ethyl lactate/7% dipropionate, () 1% ethyl lactate/0.7% dipropionate, (◯) influent 1% ethyl lactate/0.7% dipropionate, (●) tap water. Arrows show when addition of mixtures of ethyl lactate and dipropionate began and ceased. FIG. 11 shows an area plot of TCE dechlorination and daughter products in whey powder microcosms; arrows indicate addition of TCE. FIG. 12 shows a whey powder plot of fate of amended electron donor: (●) acetate, (▪) propionate, (◯) butyrate, (x) lactate, (X) COD, (●) methane; arrows show addition of electron donor. DETAILED DESCRIPTION Before the present methods for accelerating or enhancing in situ bioremediation of halogenated solvents in ground water are disclosed and described, it is to be understood that this invention is not limited to the particular configurations, process steps, and materials disclosed herein as such configurations, process steps, and materials may vary somewhat. It is also to be understood that the terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting since the scope of the present invention will be limited only by the appended claims and equivalents thereof. The publications and other reference materials referred to herein to describe the background of the invention and to provide additional detail regarding its practice are hereby incorporated by reference. The references discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the inventors are not entitled to antedate such disclosure by virtue of prior invention. It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “an electron donor” includes reference to a mixture of two or more of such electron donors, reference to “a solvent” includes reference to one or more of such solvents, and reference to “a microbe” includes reference to a mixture of two or more of such microbes. In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. As used herein, “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps. “Comprising” is to be interpreted as including the more restrictive terms “consisting of” and “consisting essentially of.” As used herein, “consisting of” and grammatical equivalents thereof exclude any element, step, or ingredient not specified in the claim. As used herein, “consisting essentially of” and grammatical equivalents thereof limit the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic or characteristics of the claimed invention. As used herein, “PCE,” “perchloroethylene,” “tetrachloroethylene,” and “tetrachloroethene” refer to Cl2C═CCl2. As used herein, “TCE,” “trichloroethylene,” and “trichloroethene” refer to Cl2C═CH—Cl. As used herein, “DCE,” “dichloroethylene,” and “dichloroethene” refer to Cl—HC═CH—Cl. As used herein, “VC” and “vinyl chloride” refer to H2C═CH—Cl. As used herein, “ethylene” and “ethene” refer to H2C═CH2. As used herein, “chloroethenes” means PCE, TCE, DCE, VC, and mixtures thereof. As used herein, “biotransformation” means a biological reduction in the number of halogen, e.g., chlorine, atoms covalently bound to an organic compound. For example, PCE can be biotransformed to TCE, which can be biotransformed to DCE, which can be biotransformed to vinyl chloride, which can be biotransformed to ethylene. If the rate of biotransformation is increased by adding an electron donor to the ground water, then the biotransformation is enhanced. As used herein, “microbe” means a microscopic organism, such as bacteria, protozoa, and some fungi and algae. Bacteria are illustrative microbes according to the present invention. Biotransformation is enhanced, at least in part, by stimulating indigenous, naturally occurring microbes in the ground water. If indigenous, naturally occurring microbes are not present or are not sufficiently effective, then an appropriate microbe can be added to the ground water, as well as the electron donor of the present invention. The microbe can be added before, with, or after adding the electron donor to the ground water. Typically, the microbe is an anaerobic or facultatively anaerobic bacterium. Bacteria known to work within the current processes include Dehalococcoides ethenogenes strain 195 (X. Maymo-Gatell et al., Isolation of a Bacterium that Reductively Dechlorinates Tetrachloroethene to Ethene, 276 Science 1568-1571 (1997)), the Pinellas culture (M. R. Harkness et al., Use of Bioaugmentation To Stimulate Complete Reductive Dechlorination of Trichloroethene in Dover Soil Columns, 33 Environmental Sci. Technol. 1100-1109 (1999); D. E. Ellis et al., Bioaugmentation for Accelerated In Situ Anaerobic Bioremediation, 34 Environmental Sci. Technol. 2254-2260 (2000)), and the like, and mixtures thereof. Other species, however, are known to function, and the present invention is not limited by the examples provided herein. As used herein, “surfactant” means a substance that when dissolved in water or an aqueous solution reduces its surface tension or the interfacial tension between it and another liquid. Surfactants are characterized by a structural balance between one or more hydrophilic and hydrophobic groups. This amphiphilic nature causes them to be preferentially adsorbed at air-water, oil-water, and solid-water interfaces, forming oriented monolayers wherein the hydrophilic groups are in the aqueous phase and the hydrocarbon chains are pointed toward the air, in contact with the solid surfaces, or immersed in the oil phase. Surfactants are characterized by a critical micelle concentration (cmc), a concentration at which surfactant molecules begin to aggregate into micelles and above which more micelles are formed. Surfactants enhance solubility of nonpolar compounds in aqueous solutions by providing a microenvironment, i.e., the interior of micelles, where the nonpolar compounds can accumulate. In certain illustrative embodiments of the present invention, the electron donor is a surfactant. As used herein, a “co-solvent” is a solvent present in a minor amount as compared to a solvent with which it is mixed. Co-solvents are like surfactants in that they decrease interfacial tension between two liquid phases, but they generally do not form micelles. Thus, co-solvents enhance solubility, but not to the extent of surfactants. In the context of in situ bioremediation, the rate of enhanced solubilization mediated by a co-solvent or co-solvents is less likely to overwhelm the rate of biotransformation. Thus, in certain illustrative embodiments of the invention, the electron donor is a co-solvent. Chlorinated solvents represent two of the three most common ground water contaminants at hazardous waste sites in the United States, and with their degradation products they account for eight of the top 20. Unfortunately, chlorinated solvents are relatively recalcitrant compounds with low, but toxologically significant, solubilities in water. Historically, the conventional technology for ground water treatment has been pump-and-treat methodology. While the pump-and-treat approach can be useful for achieving hydraulic containment of a ground water contaminated with chlorinated solvents, it has very rarely been successful for restoration, largely because of the heterogeneity of the subsurface (i.e., preferential flow paths) and the presence of nonaqueous phase liquids. This has led to significant research in the last 10 years on in situ technologies for restoration of ground water contaminated with chlorinated solvents. Residual chlorinated solvent source areas (where nonaqueous contaminants are present) in the subsurface are especially problematic because the combination of low contaminant solubilities and the lack of mixing in typical ground water flow makes them very long-lived (decades to centuries). As discussed above, the common perception that bioremediation cannot effect improvements to the slow mass transfer from the nonaqueous to the aqueous phase has limited its applications to aqueous-phase contaminated ground water plumes. Also mentioned above, the technology categories used for these areas other than pump-and-treat include thermal technologies such as stream-stripping, in situ chemical oxidation, surfactant flushing, or co-solvent flushing. While these approaches generally result in some rapid mass removal of contaminants and have worked to varying degrees, they all share a common disadvantage: they have a high capital cost in the early stages of remediation. In addition, all except chemical oxidation require extraction of contaminants from the ground with subsequent treatment. This creates new exposure pathways and increases costs. Finally, these technologies rarely restore ground water to contaminant concentrations below regulatory limits, so follow-on activities are generally required. P. V. Roberts et al., Field Study of Organic Water Quality Changes during Ground Water Recharge in the Palo Alto Baylands, 16 Water Resources Research 1025-1035 (1982), reported one of the first field observations suggesting bioremediation of chloroethenes (PCE, TCE, DCE, and VC). E. J. Bouwer & P. L. McCarty, Transformation of 1- and 2-Carbon Halogenated Aliphatic Organic Compounds under Methanogenic Conditions, 45 Applied Environ. Microbiol. 1286-1294 (1983), confirmed biodegradation of PCE and TCE in the laboratory shortly thereafter. F. Parsons et al., Transformations of Tetrachloroethylene and Trichloroethylene in Microcosms and Groundwater, 76 J. Am. Water Works Ass'n 56-59 (1984), and T. M. Vogel & P. L. McCarty, Biotransformation of Tetrachloroethylene to Trichloroethylene, Dichloroethylene, Vinyl Chloride, and Carbon Dioxide under Methanogenic Conditions, 49 Applied Environ. Microbiol. 1080-1083 (1985), demonstrated that DCE and VC were generated during biodegradation of PCE under anaerobic conditions. Finally, Freedman and Gossett, supra, reported complete dechlorination of PCE to ethylene as follows: PCE→TCE→DCE→VC→ethylene. In each step of the process the compound was reduced (gaining two electrons) through substitution of a chlorine atom by a hydrogen atom. Hence this degradation pathway is often referred to as reductive dechlorination. In the reductive dechlorination process, chloroethenes act as electron acceptors. This implies that the process can be limited in the field by the availability of sufficient suitable electron donors. In fact, reductive dechlorination also can be totally or partially inhibited by the presence of competing inorganic electron acceptors, such as oxygen, nitrate, iron, and sulfate. It is now widely accepted that reductive dechlorination occurs to some extent at most field sites where chloroethene contamination exists in the presence of a sufficient supply of electron donors (P. L. McCarty, Biotic and Abiotic Transformations of Chlorinated Solvents in Groundwater, in Symposium on Natural Attenuation of Chlorinated Organics in Ground Water 5-9 (Office of Research and Development, U.S. Environmental Protection Agency, Washington, D.C., EPA/540/R-96/509, 1996); J. M. Gossett & S. H. Zinder, Microbiological Aspects Relevant to Natural Attenuation of Chlorinated Ethenes, in Symposium on Natural Attenuation of Chlorinated Organics in Ground Water 10-13 (Office of Research and Development, U.S. Environmental Protection Agency, Washington, D.C., EPA/540/R-96/509, 1996); T. H. Wiedemeier et al., Technical Protocol for Evaluating Natural Attenuation of Chlorinated Solvents in Groundwater, Draft—Revision 1 (Air Force Center for Environmental Excellence, Technology Transfer Division, Brooks Air Force Base, San Antonio, Tex., 1997). Many oxidizable organic compounds potentially could make suitable electron donors. For a potential electron donor to be useful as an amendment for enhanced in situ bioremediation, however, it must be safe to use, facilitate the desired reaction, and be relatively inexpensive. Lactate is a potential electron donor having these properties. It is innocuous enough for use in the food and medical industries. It has been demonstrated to facilitate reductive dechlorination of chlorinated solvents in several laboratory studies (e.g., W. P. DeBruin et al., Complete Biological Reductive Transformation of Tetrachloroethylene to Ethane, 58 Applied Environ. Microbiol. 1996-2000 (1992); S. A. Gibson & G. W. Sewell, Stimulation of Reductive Dechlorination of Tetrachloroethene in Anaerobic Aquifer Microcosms by Addition of Short-Chain Organic Acids or Alcohols 1392-1393 (1992), D. E. Fennel et al., Comparison of Butyric Acid, Ethanol, Lactic Acid, and Propionic Acid as Hydrogen Donors for Reductive Dechlorination of Tetrachloroethene, 31 Environ. Sci. Technol. 918-926 (1997). The cost-effectiveness of lactate has not been thoroughly evaluated, but preliminary testing suggests that it will be at least as cost-effective as other in situ remediation technologies. While the use of lactate as an electron donor to facilitate reductive dechlorination is well-established, it has only been applied for remediation of aqueous-phase contaminants because of the perception that bioremediation does not significantly enhance mass transfer of contaminants from the nonaqueous phase. It is shown herein, however, that the addition of high concentrations of a lactate solution not only facilitates reductive dechlorination of aqueous chloroethenes, but also significantly enhances mass transfer of nonaqueous contaminants, making them highly bioavailable. As used herein, “high concentrations” means high relative to the stoichiometric requirement for electron donor to degrade TCE to ethene. Thus, “high concentrations” means about 3-5 orders of magnitude greater than such stoichiometric requirements. Facilitated transport and enhanced bioavailability of nonaqueous chlorinated solvents through addition of high concentrations of an appropriate electron donor, according to the present invention, take advantage of the natural processes that have made natural attenuation so popular, while also significantly reducing source longevity by enhancing mass transfer to the aqueous phase. The capital costs of the approach are minimal, because only a simple, potentially portable, injection system and monitoring wells are required. Initial mass removal may be slower than some of the other technologies, but it is sustainable for a relatively low cost and requires no extraction of contaminated ground water except for routine monitoring. High concentrations of lactate, for example, not only provide an electron donor to expedite reductive dechlorination, but also facilitate mass transfer of the nonaqueous chlorinated solvents into the aqueous phase in a manner that makes them highly bioavailable. The lactate appears to act as a surfactant or co-solvent that brings nonaqueous chlorinated solvents into solution. The intimate contact of the chlorinated solvents (electron acceptors) in solution with the lactate (electron donor) enhances bioavailability and leads to rapid biodegradation. The depletion of the residual contamination source is potentially greatly accelerated due to the surfactant or co-solvent effect. The use of lactate to facilitate transport of chlorinated solvents into the aqueous phase and dramatically increase their bioavailability opens up a wide range of applications for enhanced in situ bioremediation of chlorinated solvents present as nonaqueous phase liquids at residual saturation in ground water. The use of a relatively inexpensive compound that accomplishes the same thing as mild surfactants or co-solvents, but does not require extraction and above-ground treatment, combines the advantages of mass removal with those of enhanced bioremediation. All of the advantages of bioremediation, such as low capital cost, in situ contaminant destruction, unobtrusive appearance, public acceptance, low maintenance requirements, and the like, can be applied to residual source areas because, using this process, source longevity can potentially be greatly reduced. Many of these benefits are enjoyed by owners of contaminated sites, but reduced risk of further releases of contaminants to the public and the environment is also important. The most appropriate application of this process is to sites with residual chlorinated solvent source areas in the subsurface, comprising primarily nonaqueous contaminants at residual saturation. These are common at both federal and industrial facilities. When very large, mobile DNAPL pools are present, mass transfer rates may be too slow to effect remediation in a reasonable time frame, and more aggressive, capital-intensive approaches may be warranted. EXAMPLE 1 A 1-year field evaluation of enhanced in situ bioremediation was performed at Test Area North (“TAN”) of the Idaho National Engineering and Environmental Laboratory. FIG. 1 shows a site plan of TAN, wherein solid symbols represent monitoring wells (10) and open symbols represent injection wells (12). The locations of a 5,000 μg/L TCE isopleth (14); 1,000 μg/L TCE isopleth (16); 100 μg/L TCE isopleth (18); and 5 μg/L TCE isopleth (20) are shown by solid lines. FIG. 2 illustrates a cross section of this site, showing the surface of the ground (22), an approximately 63-m (210-feet) fractured basalt unsaturation zone (24) (not drawn to scale), an approximately 60-m (200-feet) fractured basalt aquifer (26), and an impermeable clay interbed (28). The approximate location of the TCE secondary source (30) and the 1,000 μg/L TCE isopleth (32) are also indicated. The test was performed to determine whether this technology has the potential to enhance or replace the default pump-and-treat remedy selected for the contaminant source area in the site's Record of Decision. The residual source of chloroethenes (30), primarily TCE with some PCE and DCE, is present in the fractured basalt aquifer at the site, about 60 to 120 m below land surface. The residual source area (30) is approximately 60 m in diameter, and the TCE plume emanating from the this source is approximately 3 km long. Based on results of published studies and site-specific laboratory studies (K. S. Sorenson, Design of a Field-Scale Enhanced In Situ Bioremediation Evaluation for Trichloroethene in Ground Water at the Idaho National Engineering and Environmental Laboratory, ASAE, St. Joseph, Mich., Paper No. PNW98-113 (1998)), sodium lactate was chosen as the electron donor and was injected in Well TSF-05 in concentrations ranging from 3% to 60% by weight (Table 2). The initial electron donor addition strategy involved continuous injection of potable water at 37.85 liters/minute (10 gpm) into Well TSF-05. The electron donor was to be pulsed into this line biweekly. The potable water injection began on Nov. 16, 1998, at the beginning of the startup sampling period. Potable water injection was discontinued on Dec. 11, 1998, due to a significant depression of chlorinated ethene concentrations near the injection well. It was determined that the continuous injection of clean water at 37.85 liters/minute (10 gpm) overwhelmed the flux of contaminants from the secondary source. This condition was considered undesirable for evaluation of an in situ technology, so the electron donor addition strategy was modified such that potable water was only injected for 1 hour following injection of the electron donor solution to flush the solution into the formation surrounding the injection well. This was intended to prevent significant quantities of electron donor from collecting in the injection well and to help prevent biofouling. The raw electron donor solution used was food grade sodium lactate. Table 2 presents the injection date, the sodium lactate concentration in percent by weight, the injection rate in units of gallons per minute, the total volume of electron donor injected in gallons, and the volume in gallons of potable water injected at 75.7 liters/minute (20 gpm) to flush the solution into the formation. Lactate injections began on Jan. 7, 1999, and were continued until Sep. 8, 1999. Four injection solution concentrations were used, each being more dilute than the previous solution. The dilutions were made in an effort to keep the lactate in the upper part of the aquifer, reducing density effects that cause the electron donor solution to sink to the base of the aquifer. Because the total mass of lactate was kept constant, and the injection flow rate was not dramatically increased, the duration of injection increased from 30 minutes to 4 hours. TABLE 2 Sodium Lactate Injection Total Potable Water Concentration Flow Rate Volume In- Flush Volume Date (%) (gpm) jected (gal) (gal) 1/7/1999 60 10 300 1,200 1/12/1999 60 10 300 1,200 1/19/1999 60 10 300 1,200 2/2/1999 30 20 600 1,200 2/9/1999 30 20 600 1,200 2/16/1999 30 20 600 1,200 2/23/1999 30 20 600 1,200 3/2/1999 6 25 1,500 1,200 3/4/1999 6 25 1,500 1,200 3/9/1999 6 25 1,500 1,200 3/11/1999 6 25 1,500 1,200 3/16/1999 6 25 1,500 1,200 3/18/1999 6 25 1,500 1,200 3/23/1999 6 25 1,500 1,200 3/25/1999 6 25 1,500 1,200 3/30/1999 6 25 1,500 1,200 4/1/1999 6 25 1,500 1,200 4/6/1999 6 25 1,500 1,200 4/8/1999 6 25 1,500 1,200 4/13/1999 6 25 1,500 1,200 4/15/1999 6 25 1,500 1,200 4/22/1999 6 25 3,000 1,200 4/28/1999 6 25 3,000 1,200 5/5/1999 6 25 3,000 1,200 5/12/1999 6 25 3,000 1,200 5/19/1999 6 25 3,000 1,200 5/26/1999 6 25 3,000 1,200 6/2/1999 6 25 3,000 1,200 6/9/1999 3 25 6,000 1,200 6/16/1999 3 25 6,000 1,200 6/23/1999 3 25 6,000 1,200 6/30/1999 3 25 6,000 1,200 7/7/1999 3 25 6,000 1,200 7/14/1999 3 25 6,000 1,200 7/21/1999 3 25 6,000 1,200 7/28/1999 3 25 6,000 1,200 8/4/1999 3 25 6,000 1,200 8/11/1999 3 25 6,000 1,200 8/18/1999 3 25 6,000 1,200 8/25/1999 3 25 6,000 1,200 9/1/1999 3 25 6,000 1,200 9/8/1999 3 25 6,000 1,200 Eleven monitoring wells (i.e., TAN-D2, TAN-9, TAN-10A, TAN-25, TAN-26, TAN-27, TAN-28, TAN-29, TAN-30A, TAN-31, and TAN-37) were sampled biweekly and analyzed for electron donors, biological activity indicators, competing inorganic electron acceptors and their reduced products, chloroethenes, ethene, pH, temperature, and specific conductivity. Electron Donor Distribution. Because concentrated lactate solutions are denser than water, their injection into an aquifer can cause density-driven flow downward in the aquifer. At TAN, some density-driven flow was desirable during lactate addition because the zone to be treated was approximately 60 m thick but the injection well (TSF-05) was completed only in the upper 30 m. It was apparent after the first month of injections, however, that too much of the lactate solution was moving into the lower half of the zone before spreading horizontally in the upper half of the zone. For this reason, the concentration of the lactate was reduced and the injection duration was increased in steps over several months. The importance of the lactate addition strategy can be seen in well TAN-31, a cross-gradient well completed in the upper half of the treatment zone approximately 15 m from the injection well (FIG. 3A). The increasing lactate concentrations after 150 days correspond to the third (and final) step in changing the injection strategy. Redox Conditions and Reductive Dechlorination. The effect of lactate addition on redox conditions, and ultimately on reductive dechlorination, is evident in FIGS. 3A-C. Sulfate reduction actually began at the fairly modest lactate concentrations in well TAN-31 during the first 100 days of the test, with minor iron reduction evident from increasing ferrous iron concentrations (FIG. 3B). After sulfate was depleted, TCE transformation to cis-1,2-dichloroethene (cis-DCE) began (FIG. 3C). Reductive dechlorination stopped at cis-DCE until the lactate concentrations increased after 150 days and methanogenesis began. Transformation of cis-DCE to vinyl chloride and ethene coincided almost exactly with the onset of methanogenesis. Beyond about 200 days from the start of the test, ethene was by far the largest constituent at this sampling location. Enhanced reductive dechlorination of TCE to ethene was observed in all wells receiving significant lactate concentrations. Based on the results of the field evaluation, enhanced in situ bioremediation was selected to replace pump-and-treat for remediation of the residual contaminant source area at Test Area North. Of particular importance in the decision process was the fact that the process was effective not only for degrading chlorinated solvents in the aqueous phase, but also that the process seemed to have a significant impact on the residual source itself. Enhanced Bioavailability. A surprising observation during the field evaluation was a dramatic increase in TCE concentrations deep in the aquifer soon after sodium lactate addition began (FIG. 4). The TCE increase appeared to occur essentially simultaneously with the arrival of the highly concentrated electron donor solution. In addition, the peak TCE concentration was actually significantly higher than historical measurements for well TAN-26. These observations strongly suggest that the transport of TCE to well TAN-26 was associated with the downward migration of the electron donor. This could occur through two mechanisms. One possible explanation for the large, rapid increase in TCE concentrations is that the lactate solution simply pushed secondary source material along in front of it as it migrated out from well TAN-05, through the secondary source, and down toward well TAN-26. However, tritium was a co-contaminant in the residual source material, and consideration of the tritium data in well TAN-26 appears to rule out this possibility. In fact, tritium concentrations were completely unaffected in spite of large increases in organic contaminant concentrations (TCE and DCE). A second possible explanation for increased TCE concentrations in well TAN-26 is that the lactate injection led to facilitated transport of the organic contaminants. Three hypotheses that could explain facilitated transport are as follows: (1) that the lactate solution acts as a co-solvent for the organic contaminants, (2) that the lactate acts as a surfactant, and (3) that the lactate solution, because of its high concentration, displaces sorbed chlorinated ethenes, driving them into solution. All of these mechanisms would result in facilitated transport of the chlorinated ethenes in intimate contact with the lactate solution and would make more of the chlorinated ethenes bioavailable. The behavior of the TCE in well TAN-26 after the peak concentration suggests that it was, in fact, extremely bioavailable. The drop in TCE concentration from the peak concentration to undetectable levels occurred with a TCE half-life of less than 20 days (assuming first-order kinetics for illustration). Just as important for the facilitated transport hypothesis, cis-DCE increased to a peak concentration within 20% of the peak TCE concentration (indicating an excellent mass balance), and then remained elevated near that peak concentration. The significance of this point is that the lactate injection was continuing, so if the hypothesis were valid it would be expected to continue bringing the organic contaminants with it as it migrated through the secondary source. After biological activity increased, the TCE was transformed to cis-DCE before reaching well TAN-26, but as shown in FIG. 4, the total ethene level remained approximately constant. After several months the total ethene concentration dropped, but this was expected (and intentional) because the lactate solution concentration had been reduced by a factor of 20 in June. This change reduced the density of the solution significantly, so less lactate, and therefore less total ethenes, was transported to well TAN-26. Thus, the concentration decrease supports the hypothesis of facilitated transport. The facilitated transport makes available for reductive dechlorination large quantities of the chlorinated ethenes that otherwise would remain associated with the secondary source. As shown by the well TAN-26 data, once made available by the lactate solution, the TCE was, in fact, rapidly degraded. Enhanced bioavailability of chlorinated ethenes in the secondary source would greatly decrease the longevity of the source. EXAMPLE 2 Based on the field results presented in Example 1, laboratory studies were preformed to confirm that the enhanced bioavailability of TCE observed in the field was due to co-solvent or surfactant behavior resulting from the use of high concentrations of sodium lactate. Two fundamental properties used to screen the co-solvent or surfactant properties of a solution are surface tension and interfacial tension. Surface tension measures the force per unit length along the interface between a liquid and air due to its tension. When a co-solvent or surfactant is present in an aqueous liquid at increasing concentrations, the surface tension of that liquid decreases. Interfacial tension is similar to surface tension except that it measures the force per unit length along the interface between two liquid phases arising from the surface free energy. The higher the interfacial tension between two liquids, the less likely one is to dissolve into the other, and the more difficult it is for one to be transported within the other. Thus, perhaps the most significant property of co-solvents and surfactants in the context of chlorinated solvent remediation is that they decrease the interfacial tension between the aqueous phase (groundwater) and the organic nonaqueous phase so that the solubility (or mobility for order-of-magnitude decreases) of the nonaqueous phase is enhanced. The laboratory study performed to confirm the co-solvent properties of the high concentration electron donor solution measured the surface tension of electron donor solutions at various concentrations. Next, interfacial tensions between the same electron donor solutions and nonaqueous phase TCE were measured. Two types of electron donor solutions were used. The first was different concentrations of sodium lactate, the electron donor used in Example 1. The second was various mixtures of sodium lactate and ethyl lactate. Ethyl lactate was chosen because it is a lactate-based compound that is used in some industries as a solvent. Thus it was believed ethyl lactate might further enhance the co-solvent behavior observed, while still acting as a suitable electron donor for bioremediation. It is believed that mixtures of sodium lactate and ethyl lactate have never before been used for bioremediation. Surface and interfacial tension measurements were made using the pendant drop method (M. J. Rosen, ed., Structure/Performance Relationships in Surfactants, American Chemical Society, Washington D.C. 329 (1984); R. D. Bagnall & P. A. Arundel, The Profile Area of Pendant Drops, 82 J. Phys. Chem. 898 (1978)) coupled with real-time video imaging (M. D. Herd et al., Interfacial Tensions of Microbial Surfactants Determined by Real-Time Video Imaging of Pendant Drops, Proceedings paper number SPE/DOE 24206 513-519, SPE/DOE Eighth Symposium on Enhanced Oil Recovery, Tulsa, Okla. (1992)). The results of the surface tension experiment are shown in FIG. 5. Surface tension is plotted on the vertical axis, while sodium lactate concentration for each solution is plotted on the horizontal axis. The different lines on the plot are for different concentrations of ethyl lactate ranging from 0 to 10% mixed with the sodium lactate solution. Error bars represent two standard deviations around the mean. Examination of the 0% ethyl lactate line (sodium lactate only) reveals that at sodium lactate concentrations from 0.01 to 7%, almost no change in surface tension occurred. As the concentration was increased to 30 and 60%, however, a dramatic decrease in the surface tension was measured. This result confirms that sodium lactate begins to exhibit co-solvent properties at high concentrations. These concentrations are about 3 orders of magnitude higher than reported in other studies, which explains the surprising results discussed in Example 1. In an effort to decrease the sodium lactate concentrations required to lower the surface tension of the solution, mixtures with ethyl lactate were evaluated. As seen in FIG. 5, the addition of 1% and 10% ethyl lactate to the different sodium lactate solutions had a pronounced effect on the solution's surface tension. Thus, the addition of ethyl lactate to the sodium lactate electron donor solution enhances its co-solvent properties. The choice of optimum concentration would be a matter of design for a specific remediation. If only slightly enhanced bioavailability of the solvents were desired, the high concentration sodium lactate solution would be appropriate. If a large degree of enhanced bioavailability were desired, the addition of 1 to 10% ethyl lactate would be appropriate. The results of the interfacial tension measurements are shown in FIG. 6. As before, error bars represent two standard deviations around the mean. For 0% ethyl lactate (sodium lactate only), the effect of increasing sodium lactate concentration occurs at lower concentrations for interfacial tension than observed in the surface tension measurements. Interfacial tension decreased by about 26% when sodium lactate was increased from 0.1 to 3% (still 2 orders of magnitude above previous studies). When sodium lactate was increased to 30%, the interfacial tension was decreased to 47% of the value at a sodium lactate concentration of 0.1%. Again, the importance of high sodium lactate concentrations for achieving the co-solvent properties is apparent. As ethyl lactate was added to the sodium lactate solutions, it is clear that the ethyl lactate concentration is the primary factor affecting interfacial tension. FIG. 6 shows that the interfacial tension becomes relatively insensitive to sodium lactate concentration for the ethyl lactate mixtures. From a remediation design standpoint, this simplifies things because co-solvent effects appear to be affected by only one component of the mixture. Interestingly, only the 10% ethyl lactate mixture displayed lower surface tensions than the 30% sodium lactate solution with no ethyl lactate. EXAMPLE 3 Understanding the movement of an electron donor through a specific aquifer matrix is critical in assessing the potential biological area of influence that would result from injection of an electron donor into the aquifer. Consideration of inhibition of flow due to physical and geochemical interactions between the electron donor and the matrix is important in assessing the potential use of electron donors. At TAN, the interaction of the electron donor with the TCE residual source (any nonaqueous form of chlorinated solvents) must also be considered. Enhanced solubility of the residual source has significant impacts on remediation time frame and costs. Potential factors influencing electron donor migration include interaction between the aqueous and non-aqueous phases in the aquifer, suspended solids content, the ability to emulsify or dissolve the electron donor, and the physical properties of the electron donor solution, including solubility, viscosity, and sorption to the solid matrix. Most of the general properties could be determined during the initial screening phase of the electron donor using published data. The TAN aquifer is comprised of fractured basalt intercalated with sedimentary beds. The sedimentary beds are relatively impermeable and, as a result, the majority of groundwater flow occurs through the basalt fractures. Therefore, when assessing an electron donor, four parameters were used to evaluate the potential flow limitations and interactions with TCE DNAPL of the electron donor through basalt, as follows: (1) transportability of the electron donor through a basalt matrix, (2) retention of the chemical oxygen demand (COD) during transport through a basalt matrix, (3) retention of interfacial tension reduction through a basalt matrix, and (4) effect of the electron donor on the solubility of TCE DNAPL in the basalt matrix. Basalt columns were prepared by crushing basalt and collecting particles that were retained by a 1.6-mm mesh size sieve but passed through a 3.2-mm mesh size sieve. The sized basalt particles were washed with water to remove fines, sterilized by autoclaving, slurried with tap water, and packed into 28.5×5.03-cm inside diameter glass columns in 3-cm lifts. The columns were then capped with plexiglass end plates tapped for nylon plumbing fittings. A fabric mesh screen and a rubber gasket were placed between the end plates and the crushed basalt to seal the column during tightening of a metal frame threaded through the end plates. All column components were either autoclaved or surface-disinfected with dilute sodium hypochlorite solution. The columns were generally used within one week of packing. The columns were clamped to a metal support lattice and operated in the up-flow mode. Polyethylene tubing and nylon and stainless steel fittings were used to connect the flow units to a pressure gauge, peristaltic pump, electron donor solution reservoir, and waste container. The columns were initially saturated with tap water, air pockets were eliminated, and mass measurements were made to obtain porosities. The electron donor solutions were prepared such that they mimicked the proposed solution that would be injected in the field setting. For instance, sodium lactate has been injected at TAN in concentrations between 3 and 60%; the concentrations of sodium lactate controls used during this study were between 1 and 15%. The electron donor solutions were pumped into each column using a multi-head peristaltic pump, which allowed the columns to be operated at the same flow velocity and pore volume period (1 hour). Three four-column experiments were set up for this study. They included one for each of the two electron donor solution concentrations tested, one tap water positive control, and one ionic strength positive control using sodium chloride, when necessary (e.g., when testing sodium lactate). The flow rate used (5 mL/min) was intended to represent a velocity reflective of a realistic injection velocity at TAN (1 ft/day). Initial influent and subsequent effluent COD readings and interfacial tension samples (where applicable) were taken to assess movement of the electron donor solution through the basalt matrix. TCE Analysis. TCE samples were taken from the effluent of the columns and negative control samples were taken from the influent. These samples were analyzed by injecting the liquid samples (100 μL) directly into an HP5890 Series II gas chromatograph (GC) equipped with an electron capture detector (ECD) and an Rtx-624 column. Samples were injected with an autosampler from 2-mL samples collected with no headspace. The samples collected were analyzed within 72 hours and usually within 24 hours. COD Analysis. Samples (2.7 mL) were taken of the influent electron donor solution, and periodically of the effluent, and preserved using concentrated sulfuric acid (0.3 mL). Samples were analyzed in accordance with the Hach 10067 method. Sampling frequency was generally 3 times during equilibration of the columns, 4 to 5 times during alternate amendment, and 1 to 3 times after water was re-amended to all of the columns. Interfacial Tension Analysis. IFT measurements were taken for the effluent of the electron donor solutions and from the influent as a control. Sampling frequency was the same as the COD analysis except that 10-mL samples were taken. The samples were prepared for analysis by amending each with approximately 750 mg/L TCE and equilibrating them at least overnight. Samples were prepared in 25-mL or 50-mL serum vials capped with Teflon-lined rubber septa and were immediately placed on a shaker table set at 150 rpm. Measurement were made using an Intefacial Tensiometer, M. D. Herd et al., Interfacial Tensions of Microbial Surfactants, Determined by Real-Time Video Imaging of Pendant Drops, paper SPE-DOE 24206 presented at the SPE/DOE Eighth Symposium on Enhanced Oil Recovery, Tulsa (22-24 Apr. 1992). Briefly, a drop of less dense liquid was injected upward into a cell containing the more dense liquid using a syringe pump. The interface between the two liquids formed an image that was captured by a video camera, magnified, and displayed on a computer monitor. The interfacial tension was then calculated using the dimensions of the drop and the density difference between the two liquids. The column studies were performed by setting up the saturated columns, inoculating them with TCE DNAPL, and allowing them to run overnight at a very low flow rate (˜0.1 mL/min) in order to allow sorption of the TCE onto the basalt matrix. The columns were loaded with TCE DNAPL (150 μL) by using a glass, airtight syringe with a long needle, placing the needle approximately half-way down the column, and placing drops of TCE DNAPL up the column. Approximately 16 hours later, the flow rate was increased to 5 mL/min and sampling of the columns began. TCE samples were collected every 20 to 30 minutes, and two to three COD and IFT samples were collected during the period when tap water was the amendment. The columns were allowed to run for approximately 4 hours using the tap water so that the effluent TCE concentration could reach equilibrium. After this period, electron donors were amended to each respective column (including a tap water control column), TCE samples were collected every 20 to 30 minutes, and COD and IFT samples were collected every hour. Again, enough time was allowed to pass (approximately 4 hours) so that equilibrium in the effluent TCE concentrations could be achieved in each column. All columns were then switched back to tap water and samples were collected as before in order to determine any rebound effects. In this example, 1% and 10% whey powder solutions were used as the electron donors. In this connection, 1% whey powder solution was prepared by dissolving 50 g of whey powder in 4,950 ml of water (density=1.01 g/mL), and 10% whey powder solution was prepared by dissolving 500 g of whey powder in 4,500 mL of water (density=1.04 g/mL). Analysis of relative effluent TCE concentrations was used to determine the effect of the electron donor solution on TCE DNAPL solubility. The equilibrium effluent TCE concentration in each column using tap water was used as the baseline from which the equilibrium effluent TCE concentrations using the alternate amendment solution could be compared. The relative difference in TCE concentration was used as an indicator for enhanced solubility of TCE DNAPL using the alternate amendment as compared with tap water. IFT analysis was also performed to see if enhanced TCE solubility could be correlated with significant drops in IFT between the electron donor solution and tap water. Analysis of COD was performed to assess the retention of the electron donor solution through the basalt-packed columns. The difference between the influent and effluent COD was calculated during the alternate amendment to determine the relative percentage of the electron donor that moves through the basalt compared to the sodium lactate positive control. Differences between the physical appearance of the influent and effluent electron donor solutions were also noted. These parameters were used to assess the relative donor migration potential (relative to the sodium lactate positive control) of the electron donor through a basalt matrix. Column pressure was also closely monitored throughout the experiment. The column pressure of the electron donor solution was assessed in order to determine if clogging of the column was occurring as a result of amendment with the electron donor solution. Column experiment results using whey powder were significantly different than those observed using sodium lactate as the column amendment (FIGS. 7 and 8). Initial effluent TCE concentrations were considerably lower than the initial concentrations for sodium lactate. The columns were allowed to equilibrate until effluent TCE concentrations were 9.4 ppm for tap water, 8.6 ppm for 10% whey powder amended, and 6.1 ppm for the 1% whey powder amended columns. The alternate amendments were then made to each respective column. Following the start of amendment, TCE concentrations remained relatively unaffected for approximately 1.7 hours (1.7 pore volumes). As shown in FIG. 7, effluent TCE concentrations increased approximately 1.7 pore volumes after the 10% whey powder amendment began to peak at concentrations of approximately 34 ppm (relative difference approximately 24 ppm). Elevated effluent TCE concentrations were observed during the period of whey powder amendment. The TCE concentration in the effluent, however, decreased slightly to approximately 15 ppm during the last three sample points of the whey powder amendment. After the amendment was switched back to tap water, the effluent TCE concentrations dropped below 5 ppm, suggesting that significant TCE DNAPL may have been removed during the whey powder amendment. The 1% whey powder amendment showed no significant difference in TCE concentrations in the column effluent as compared with the tap water baseline. TCE concentrations in this column ranged from 5 to 10 ppm throughout the duration of the experiment regardless of the amendment. TCE concentrations in the tap water control also maintained an equilibrium concentration of approximately 8 ppm throughout most of the experiment, although concentrations dropped to less than 5 ppm after 7 pore volumes. The increase in TCE concentration observed in the column effluent during the 10% whey powder amendment could be correlated to an increase in COD concentration. COD concentrations also substantially increased in the 1% whey powder column effluent during amendment of the whey powder solution, but this could not be correlated to an increase in TCE concentrations. COD concentration in the column effluent in the whey powder columns reached approximately 77,000 ppm during the 10% amendment and approximately 8,000 ppm during the 1% amendment. These concentrations were slightly higher than the 73,000 and 7,300 ppm measured for the influent solutions. These numbers illustrate that COD was not lost in the columns during the column experiment. Pressure changes were also not observed during the whey powder amendment; therefore, transportability of the whey powder solutions through the columns appeared to be satisfactory. COD measurements were zero for the tap water used in the influent and for all effluent column samples collected when tap water was the amendment. The increased TCE concentrations during the 10% whey powder amendment could also be correlated to IFT reductions (FIG. 8). The reduction in IFT between TCE DNAPL and the column effluent occurred immediately following the start of the whey powder amendment, and IFT remained low until the amendment was terminated. IFT measurements of effluent correlated well with IFT measurements of influent (approximately 14 dynes/cm), suggesting retention of IFT properties during transport through the column. IFT reductions, however, were also observed in the 1% whey powder column, as measurements were approximately 37 dynes/cm during tap water amendment and 20 dynes/cm during whey powder amendment. Therefore, IFT reductions during low concentration whey powder amendment did not correlate with enhanced solubility of TCE DNAPL in the column. All IFT measurements made of the tap water column influent and effluent were between 37 and 38 dynes/cm. Based on visual observation, monitoring of pressure and differences in COD measurements between solution amendments and column effluents, whey powder was transported efficiently through the basalt columns. The whey powder amendment resulted in direct enhancement of TCE dissolution. Whey powder resulted in an average increase of approximately 22 ppm during amendment as compared to tap water. This enhanced dissolution of TCE was correlated with an interfacial tension measurement reduction and an increase in COD, as measured in the column effluent. EXAMPLE 4 In this example, the procedure of Example 3 was followed except that a mixture of dipropionate and ethyl lactate was substituted for whey powder solution. The mixtures were either 10% ethyl lactate+7% dipropionate and 1% ethyl lactate+0.7% dipropionate. Results of data collected during column experiments conducted to assess a mixture of ethyl lactate/dipropionate are shown in FIGS. 9 and 10. The effluent TCE concentrations observed during the tap water equilibration period were between 27 and 28 ppm (10%/7% and 1%/0.7% ethyl lactate/dipropionate) and 7 ppm (tap water) for the columns used in this study. Overall, the effect of increasing concentrations of the ethyl lactate/dipropionate mixture resulted in increased solubility of TCE DNAPL, an effect similar to what was observed during the whey powder column experiments (Example 3). Following amendment with 1%/0.7% ethyl lactate/dipropionate, the column effluent TCE concentrations increased from approximately 27 ppm during tap water equilibration to a peak concentration of 67 ppm during the amendment. Following amendment termination, the effluent TCE concentration in the column steadily dropped to a concentration of approximately 20 ppm and 2.3 pore volumes after the influent was switched back to tap water. A similar trend was observed with the lower concentration (1%/0.7% ethyl lactate/dipropionate) amendment column, although the magnitude of the change was much less. The effluent TCE concentrations increased from approximately 27 ppm to a peak concentration of 36 ppm as the amendment was switched from tap water to the low concentration ethyl lactate/dipropionate mixture. Once the low concentration amendment was terminated, the TCE effluent concentration dropped to approximately 23 ppm during the tap water flush. The tap water control column TCE effluent concentrations initially reached equilibrium at approximately 7 ppm and gradually increased to approximately 10 ppm toward the end of the experiment. The increased TCE effluent concentrations observed during amendment of the high concentration (10%/7%) ethyl lactate/dipropionate mixture corresponded with decreased IFT measurements in the column effluent. The IFT dropped to approximately 12 dynes/cm during the high concentration amendment, which is similar to the IFT observed for the influent ethyl lactate/dipropionate solution. Therefore, the IFT properties were conserved during transport of the ethyl lactate/dipropionate solution through the basalt matrix. This is in contrast with the dipropionate column results, where IFT reduction did not correspond with increases in effluent TCE concentrations. Therefore, the ionic strength effect observed with the dipropionate alone was not observed for the ethyl lactate/dipropionate mixture. A slight decrease in IFT was also observed during amendment of the low concentration (1%/0.7%) ethyl lactate/dipropionate. This decrease in IFT also corresponded with increased effluent TCE concentrations in the basalt column. The IFT measurements in the column effluent during the low concentration amendment were comparable to the influent IFT measurements (both were around 30 dynes/cm). The tap water control column had IFT values that were stable at approximately 39 dynes/cm. In general, IFT reductions resulting from ethyl lactate/dipropionate amendments correlated to enhanced TCE dissolution, as indicated by enhanced concentrations of TCE in the basalt column effluent. Based on visual observation, monitoring of pressure, and differences in COD measurements between solution amendments and column effluents, the mixtures of ethyl lactate and dipropionate were transported efficiently through the basalt columns. The mixture of ethyl lactate and dipropionate resulted in direct enhancement of TCE dissolution. The mixture of ethyl lactate and dipropionate resulted in an average increase of approximately 32 ppm as compared to tap water. The enhanced dissolution of TCE was correlated to an IFT measurement reduction and an increase in COD, as measured in the column effluent. Interestingly, ethyl lactate alone had no observable effect on TCE solubility, while dipropionate by itself inhibited the dissolution of TCE. Therefore, the combination of ethyl lactate and dipropionate was not expected to enhance the dissolution of TCE DNAPL. EXAMPLE 5 Dechlorination studies were carried out to determine if whey powder solutions facilitate complete degradation of target contaminants at reasonable rates. Microcosms were constructed in triplicate sets. These microcosms were amended periodically with whey powder and TCE and analyzed monthly for TCE, its reductive degradation products, electron donor (as both COD and volatile fatty acids (VFAs)), redox, and pH. An existing laboratory, sodium lactate-fed culture, derived from TAN-25 groundwater undergoing complete anaerobic reductive dechlorination (ARD) of TCE to ethene, was used to inoculate the cultures. Fresh TAN groundwater from the source area was also used to ensure that microbial populations that have been lost as a result of laboratory conditions were present for the evaluation. Serum vials (160 mL) were used as microcosms to grow the cultures. Prior to inoculation, the microcosms, along with all other culture-contact supplies, were autoclaved at 121° C. for 20 minutes and cooled to room temperature. Inoculation of the microcosms was done in a glove box containing nitrogen (95%), carbon dioxide (2.5%), and hydrogen (2.5%). Each microcosm was loaded with the inoculum, which comprised cells from the TCE-dechlorinating culture (1 L), cells from TAN-25 groundwater (1 L), and TAN-37 groundwater (2.5 L) as the media. The culture cells were used to ensure a robust dechlorinating community was present, and cells were collected from TAN-25 groundwater to ensure the laboratory community was representative of the community at TAN. In other words, often the majority of microbial populations initially present in a particular environment are lost when that community is transferred to the laboratory; therefore, recruitment of lost populations may be necessary in order to achieve a more realistic evaluation of potential performance at a particular site. The cell pellets from the dechlorinating culture and TAN-25 groundwater were separated from the supernatant because both contained electron donors, including propionate, acetate, and lactate. TAN-37 groundwater was selected as the medium because it was anaerobic groundwater that contained little or no carbon (40 mg/L as COD with <2.5 ppm acetate and propionate) that might interfere with the evaluation of electron donor utilization. The inoculum mixture was then spiked with TCE (10 ppm), aliquoted (100 mL) into the microcosms, and each respective electron donor was added (˜200 ppm for all electron donors except whey powder [˜400 ppm]). The microcosms were then sealed with butyl-rubber septa and crimped. The headspace of each microcosm was flushed for 10 minutes with 100% nitrogen, and then an initial positive pressure of 5 psig was induced into each one. Abiotic negative control microcosms were set up in a similar manner to the test microcosms except that the culture was spiked with zinc chloride (0.1% w/v), a known anti-microbial agent. The test microcosms were prepared in triplicate and negative control microcosms were amended with whey powder and LactOil™/propionate. The study included a total of 20 microcosms. Three months after inoculation, additional electron donor was added to all of the microcosms (200 to 300 mg/L as COD). Six months after inoculation, additional electron donor was added to the whey powder, ethyl lactate/propionate, and sodium lactate microcosms. At this point, approximately 50 mL of TAN-37 groundwater was also amended to all of the biotic microcosms to replace the volume lost because of sampling. This was done by placing all of the biotic microcosms into the anaerobic chamber containing nitrogen (95%), carbon dioxide (2.5%), and hydrogen (2.5%); removing the septum; adding TAN-37 groundwater and electron donor; and replacing septum and spiking each microcosm with a TCE stock solution. TCE was amended to all of the microcosms 4 and 6 months after inoculation. Throughout these studies, the microcosms were monitored monthly for TCE, cis-DCE, trans-DCE, VC, ethene, ethane, methane, lactate, acetate, propionate, butyrate, pH, and Eh. During sampling, positive pressure was evident in all of the sampled microcosms. Analytical samples (6 mL) were removed using a glass syringe (Hamilton Co., Reno, Nev.) and a 22-gauge sterile needle. An aqueous aliquot (5 mL) was transferred immediately into a serum vial (25 mL), which was sealed prior to sample collection with a Teflon™-lined butyl rubber septum. The vial was shaken vigorously for 30 seconds, inverted, and allowed to equilibrate at room temperature for at least 3 hours. Methane, ethane, and ethene measurements were taken from the headspace of the sealed sample. Chloroethene levels in the headspace of this vial were then measured using the solid phase microextraction (SPME) technique. C. L. Arthur et al, Solid-Phase Microextraction for the Direct Analysis of Water: Theory and Practice, 10 LC•GC 656-661 (1992). Acetate, butyrate, and propionate were measured using filtered and acidified aliquots (0.5 mL) of the microcosm samples. For lactate analysis, aliquots of the chloroethene samples (4.5 mL) were used. COD and pH were measured using samples (2 mL) from each microcosm. Samples were also removed at the end of the evaluation for DNA extraction (10 mL). TCE, cis-DCE, trans-DCE, and VC were analyzed using the SPME technique. C. L. Arthur et al., supra. Liquid samples (5 mL) were placed in 25-mL glass serum bottles, sealed with a gray-butyl Teflon® lined septa, and crimped with aluminum caps. The bottles were placed in an inverted position at room temperature for 3 hours to ensure equilibrium. Volatile analytes were transferred to headspace gas within each bottle. A 0.75-μm carboxen polydimethylsiloxane-coated fiber (Supelco, Bellefonte, Pa.) was inserted through each septum and analytes were allowed to sorb onto the filter for 15 minutes. The analytes were then desorbed by inserting the fiber into the injector of a Hewlett Packard (HP) Model 5890 Series II (Hewlett Packard, Palo Alto, Calif.) GC. The GC was equipped with a 30-m, 0.32-mm ID, 1.8-μm df, RTx-624 (Restek, Bellefonte, Pa.) chromatograph column. The injector was fitted with a 1-mm SPME liner and maintained at 250° C. Helium was used as the carrier gas at a flow rate of approximately 2 mL/minute. The column temperature was initially maintained at 60° C. for 6.5 minutes and then increased to 180° C. at a rate of 70° C./minute. Analytes were detected using a flame ionization detector (FID) maintained at 280° C. The GC was calibrated for each analyte using in-house prepared standards. Calibration was verified prior to each analysis using certified control samples. Utilizing this technique, the minimum detection limit for TCE, cis-DCE, and VC is 5 parts per billion (ppb). Analysis of ethene, ethane, and methane was performed by injecting a headspace sample (100 μL), from the sample (5 mL) prepared for the volatile organic compound (VOC) analysis, into an HP Model 5890 Series II GC equipped with a FID and a 0.53-mm Rt Alumina column (Restek, Bellefonte, Pa.). Helium was used as the carrier gas at a flow rate of 6.5 mL/minute. Throughout the assay, the temperature of the column was maintained at 80° C., the injector at 250° C., and the detector at 275° C. The GC was calibrated using certified gas standards and control samples were assayed daily. Using this procedure, the minimum detection limit for ethane, methane, and ethene is 1 part per billion by volume (ppbv). Acetate, propionate, and butyrate levels were measured by filtering (0.2-mm pore size) samples and adjusting the pH to 2.0 using concentrated phosphoric acid. Typically, 100 μL of acid were added per 0.5 mL filtrate, and 1.0 μL of the acidified solution was injected directly into an HP Model 5890 Series II GC. The GC was equipped with an FID and a 30-m, 0.53-mm, 0.5-μm df Nukol column (Supelco, Inc., Bellefonte, Pa.). Helium, which was used as the carrier gas, was delivered at a flow rate of 8.2 mL/minute. The column temperature was maintained at 125° C. and the injector and detector temperatures at 225 and 250° C., respectively. The GC was calibrated as above, and the minimum detection limit for acetate, propionate, or butyrate was 0.5 mg/L. Lactate concentration was determined in filtered culture samples using a Dionex 4500i (Dionex, Sunnyvale, Calif.) ion chromatograph and a conductivity detector. The analytical column was an IonPac ICE-AS6 (Dionex, Sunnyvale, Calif.). A 0.4-mM nitric acid solution was used as the eluent (at a flow rate of 1.5 mL/minute) and 5.0-mM tetrabutylammonium hydroxide was used as the anion suppression regenerant. Using this method, the minimum detection limit for lactate was 2 mg/L. The total electron donor in each microcosm was measured as COD. Samples were analyzed in accordance with Hach 10067 method or equivalent. The pH was determined using an Orion Laboratory pH meter equipped with a pH probe (Orion Inc.). Eh was qualitatively assessed for the reactors by adding resazurin (1 mg/L) as a calorimetric indicator. If the solution was clear, then the redox condition within the reactor was methanogenic. All determinations were made at room temperature. The molar balance of TCE and its reductive products was determined by converting all analytes to gram-mole and calculating the relative conversion ratios and efficiencies. Molar area plots were then created to provide a visual representation of TCE dechlorination efficiency. The dechlorination rates and efficiencies of the electron donor cultures were then compared to the sodium lactate culture dechlorination efficiency. If complete dechlorination of TCE to ethene was observed using the electron donor, and the rates are comparable to sodium lactate, then further analysis of the electron donor for field application was warranted. Conditions within the microcosm sets were nearly the same, with pH maintained within a range of 7.5 and 8.5 in all microcosms and maintenance of methanogenic reducing conditions (as indicated by lack of color in the amended resazurin). Significant differences in dechlorination performance, however, were observed between the microcosms amended with the different electron donors. Molar area plots (FIG. 11, for example) were generated to illustrate the production of dechlorination daughter products in the test microcosms over the study period. Dechlorination daughter product cis-DCE was observed in the ethyl lactate/propionate, whey powder, dipropionate, and sodium lactate microcosms 1 month after inoculation. Whey powder had the most accumulated cis-DCE with an average concentration of 162 ppb, as compared with ethyl lactate/propionate (69 ppb), dipropionate (45 ppb), and sodium lactate (75 ppb). Two months after inoculation, the whey powder microcosms had dechlorinated nearly half of the amended (˜5 ppm) TCE to ethene. Ethene production was also observed for the ethyl lactate/propionate and sodium lactate microcosms, although this only accounted for 10% of amended TCE. Three months after inoculation, all of the TCE was gone from the whey powder, ethyl lactate/propionate, and sodium lactate microcosms and only ethene was detected. The dipropionate microcosms had depleted over 40% of the TCE, with 20% apparent as ethene. Therefore, since most of the TCE was likely depleted in these microcosms by the next sampling event (1 month later), TCE was amended to all of the microcosms. One month after this TCE addition, all of the TCE was gone in the sodium lactate and dipropionate microcosms (only ethene was present) and most of it (>87%) was gone in the whey powder and ethyl lactate/propionate microcosms. Significant ethene losses, however, were apparent during this period, as only 40 to 50% of the molar concentration of TCE could be accounted for as ethene. In all dechlorinating microcosms, the progression of dechlorination went from TCE to cis-DCE to VC to ethene. Ethane was not detected in any of the microcosms, which is consistent with observations of ARD at TAN. During the last three sampling events, trans-DCE was detected in all of the microcosms. This is likely the result of residual trans-DCE in the TAN groundwater used to re-amend the microcosms 6 months after inoculation, which is supported by the fact that it appeared in all of the microcosms at the same time and at approximately the same concentrations. Concentrations of trans-DCE were never greater than 1 μM in all microcosms. One of the main objectives of the microcosm studies was to compare electron donor utilization between the different microcosm sets. Plots demonstrating oxidation of the electron donors and subsequent production of VFAs were prepared (FIG. 12, for example). Complex electron donors such as whey powder do not have defined chemistries, so COD was used as a measurement of total electron donor. Electron donor was added to the sodium lactate, ethyl-lactate/propionate, and dipropionate microcosms on three occasions: initially, and 3 and 6 months after inoculation. Electron donor was amended to the LactOil™ and LactOil™/propionate microcosms twice: initially and 3 months after inoculation. Overall, COD reduction occurred in all biotic microcosms following electron donor addition. Concomitant with this observation was generation of the VFAs propionate and acetate in all of the microcosms. Therefore, all electron donor amendments were undergoing anaerobic fermentation or homoacetogenesis. In the whey powder negative control, reduction of COD and generation of propionate and acetate were also observed during the first 3-month period. This is likely due to increased tolerance of the culture to the zinc chloride. After adding additional zinc chloride (2%) at 4 months, COD reduction ceased, as did acetate and propionate generation. In the LactOil™/sodium propionate negative control, overall COD reduction was not observed, although acetate production was also observed during the first 3 months until additional zinc chloride was added. Methane production was also observed in all of the biologically active microcosms. Whey powder generated the most methane with concentrations increasing to over 200 μM in 3 months. In contrast, after 3 months only approximately 50 μM was generated in the sodium lactate and ethyl lactate/propionate mixture, and no significant methane production was observed in the dipropionate, LactOil™, and LactOil™/propionate microcosms. At 6 months, the headspace of the microcosms was removed along with accumulated ethene and methane. Between 6 and 7 months, methane production was again the highest in the whey powder (average 134 μM accumulated) microcosms, followed by ethyl lactate/propionate (average 58 μM accumulated), sodium lactate (average 21 μM accumulated), LactOil™ (average 18 μM accumulated), dipropionate (average 13 μM accumulated), and LactOil™/propionate (average 9 μM accumulated). No methane production was ever observed in the negative controls. Utilization rates were calculated for all of the microcosm sets that performed efficient ARD of TCE to ethene. Whey powder exhibited the highest utilization rate, followed by sodium lactate, ethyl lactate/sodium propionate, and dipropionate. In comparison to sodium lactate, it appears that whey powder was more readily utilized as an electron donor. Conversely, dipropionate was less readily utilized and may be a more long-lived electron donor in the field. | <SOH> BACKGROUND OF THE INVENTION <EOH>This invention relates to remediation of environmental contamination. More particularly, the invention relates to methods for accelerating or enhancing in situ dehalogenation of nonaqueous halogenated solvents in ground water. These methods involve adding to the contaminated ground water a composition of matter that both functions as an electron donor for halorespiration processes carried out by indigenous or exogenously supplied bacteria, wherein the nonaqueous halogenated solvents are dehalogenated and degraded to innocuous compounds, and promotes mass transfer of the nonaqueous halogenated solvents from a source into the ground water where such solvents can be broken down. For many years little care was taken in the handling of organic solvents and other materials that were used in industry and at government installations, such as military bases. Because of poor handling techniques and, occasionally, intentional dumping, many industrial sites and military bases now have contaminated areas containing relatively high concentrations of these contaminants. Chlorinated solvents, such as trichloroethylene (TCE), perchloroethylene (PCE), and other types of liquids, are common at such sites, and if not removed can infiltrate groundwater supplies, rendering the water unfit for consumption and other uses. A variety of techniques have been used to promote the removal of such chemical contaminants, both from the soil and from the ground water. The principle method of ground water remediation currently used where dense, non-aqueous phase liquids (DNAPLs) are involved is what is commonly referred to as “pump-and-treat” remediation. According to this method, wells are drilled into the contaminated area and contaminated ground water is pumped above the surface, where it is treated to remove the contaminants. The limitations of the pump-and-treat method have been documented in articles such as D. M. Mackay & J. A. Cherry, Groundwater Contamination: Pump and Treat Remediation, 23 Environ. Sci. Technol. 630-636 (1989). The authors of this article concluded that pump-and-treat remediation can only be relied on to contain ground water contamination through the manipulation of hydraulic gradients within an aquifer. The reasons for the failure of the pump-and-treat method to decontaminate aquifers are rooted in the limited aqueous solubility of many DNAPLs in ground water and other processes involving contaminant desorption and diffusion. Because of the low aqueous solubility of most DNAPLs, their removal by ground water extraction requires exceptionally long periods of time. Due to the general impracticability of the pump-and-treat method, considerable attention has been paid recently to other methods for effecting remediation. One such process is commonly referred to as enhanced solubilization. This method uses micellar surfactants to increase the effective solubility of the DNAPLs to accelerate the rate of removal. The mechanism of solubilization displayed by surfactants arises from the formation of microemulsions by the surfactants, water, and the solubilized DNAPLs. For example, Table 1 shows solubilization of PCE by various nonionic and anionic surfactants. These data indicate that even dilute surfactants can significantly increase the aqueous solubility of PCE. TABLE 1 Surfactant Surfactant Concentration PCE Solubilized (mg/l) Water 0% 240 Nonylphenol ethoxylate and 2% 11,700 its phosphate ester (1:1) Sodium diamyl and dioctyl 4% 85,000 sulfosuccinates (1:1) in 500 mg CaCl 2 /l Nonylphenol ethoxylate 1% 1,300 A serious drawback with the surfactant-enhanced aquifer remediation is that the vertical mobility of the solubilized DNAPLs substantially requires that an aquiclude be present to catch any solubilized contaminant that migrates vertically. Many aquifers, however, lack such an aquiclude. If the traditional surfactant-enhanced aquifer remediation method were to be used with an aquifer lacking an aquiclude, there is a significant risk that the solubilized DNAPLs will spread vertically and contaminate an increasingly large volume. Another drawback of surfactant-enhanced aquifer remediation is the need to pump high concentrations of contaminated water above ground, which results in exposure risks to workers and the environment, and the need to dispose or recycle the surfactant. Another method for effecting remediation of ground water contaminated with DNAPLs is known as enhanced bioremediation. Enhanced bioremediation, as opposed to intrinsic bioremediation, of halogenated solvent-contaminated ground water falls into the two broad categories of aerobic and anaerobic bioremediation. The aerobic processes, regardless of whether they are carried out in situ or in a bioreactor, require addition of (1) oxygen as the electron acceptor for catabolism of the halogenated solvents, and (2) a carbon source, such as methane, propane, phenol, toluene, or butane. The utilization of an appropriate carbon source induces an enzyme that fortuitously degrades many halogenated solvents, but without any immediate benefit to the microorganisms involved. This process has been applied in situ to aqueous contamination in several instances, and at least one patent has been granted for this approach (U.S. Pat. No. 5,384,048). It has also been used to treat aqueous contamination in above-ground bioreactors with numerous variations, especially using proprietary microorganisms and nutrient mixes. Many patents have been granted in this area, e.g., U.S. Pat. No. 5,057,221; U.S. Pat. No. 5,962,305; U.S. Pat. No. 5,945,331. Anaerobic bioremediation of halogenated solvents is a fundamentally different process than aerobic bioremediation. Under appropriate anaerobic conditions, chlorinated solvents can be used directly by some microorganisms as electron acceptors through a process that has come to be known as “chlororespiration,” or, more generally, “halorespiration.” D. L. Freedman & J. M. Gossett, Biological Reductive Dechlorination of Tetrachloroethylene and Trichloroethylene to Ethylene Under Methanogenic Conditions, 55 Applied Environ. Microbiol. 2144-2155 (1989), first published the complete degradation pathway for chlorinated ethenes to ethene. In the following years, several publications reported evidence that the degradation could be achieved through microbial respiration, indicating that the microorganisms could actually grow by using chlorinated solvents directly as electron acceptors. The primary requirement to facilitate this process is the addition of a suitable electron donor or carbon source. Many electron donors have been described in the literature, including acetate, lactate, propionate, butyrate, formate, ethanol, hydrogen, and many others. U.S. Pat. No. 5,277,815 issued in 1994 for in situ electron donor addition along with control of redox conditions to effect the desired end products. U.S. Pat. No. 5,578,210 issued later for enhanced anaerobic in situ bioremediation using “biotransformation enhancing agents,” i.e., electron donors such as propylene glycol, glycerol, glutamate, a mixture of proteose peptone, beef extract, yeast extract, malt extract, dextrose, and ascorbic acid, and mixtures thereof. Based primarily on what was publicly available in the scientific literature, studies of enhanced anaerobic in situ bioremediation of chlorinated solvents began in the mid-1990s. This approach generally includes electron donor addition, sometimes with other micronutrients, to facilitate biotransformation of aqueous-phase contaminants. To date, only a few large-scale studies have been published in the peer-reviewed literature, but environmental consulting companies and remediation contractors are increasingly using the general approach. With one very recent exception, discussed below, all of the work done in this area to date has focused on the biodegradation of aqueous contaminants, because microorganisms cannot directly degrade nonaqueous contaminants. Consequently, bioremediation is not generally thought to be applicable to sites with residual DNAPLs in the subsurface. Therefore, the technologies currently in use include thermal technologies such as steam stripping, in situ chemical oxidation, surfactant flushing, or co-solvent flushing. Surfactant (or co-solvent) flushing, briefly described above, is a chemical process that aims to facilitate transport of nonaqueous contaminants, but without attention to biodegradation. At many sites, however, the pump-and-treat process continues to be used to hydraulically contain residual source areas although it is almost universally accepted that these systems will have to operate in perpetuity because of their inefficient removal of nonaqueous contaminants. The notable recent exception to the focus of bioremediation on aqueous contaminants away from residual source areas is a study by C. S. Carr et al., Effect of Dechlorinating Bacteria on the Longevity and Composition of PCE-Containing Nonaqueous Phase Liquids under Equilibrium Dissolution Conditions, 34 Environ. Sci. Technol. 1088-1094 (2000), demonstrating that anaerobic bioremediation of tetrachloroethene (PCE) enhanced mass transfer from the nonaqueous phase to the aqueous phase and significantly shortened the longevity of the nonaqueous source. The mechanisms identified were (1) enhanced dissolution of PCE resulting from the continuous removal of the compound from the aqueous phase by bacteria, and (2) increased solubility of the intermediate chlorinated ethenes relative to PCE, allowing the total moles of chlorinated ethenes in the aqueous phase to increase due to biotransformation. This study is important because it identifies some of the advantages of enhancing mass transfer from the nonaqueous phase to the aqueous phase. In view of the foregoing, it will be appreciated that providing methods for accelerating or enhancing in situ bioremediation of halogenated solvents in ground water would be a significant advancement in the art. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>It is an advantage of the present invention to provide a method for in situ remediation of DNAPLs in ground water wherein capital costs are low. It is also an advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein mass transfer from the nonaqueous phase to the aqueous phase is enhanced. It is another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the longevity of source areas is shortened. It is still another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein no extraction of contaminated water from the ground is required. It is yet another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water such that the concentrations of the solvents are restored to below regulatory limits and no follow-on remediation activities, other than perhaps monitored natural attenuation, are needed. It is a still further advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the DNAPLs are more rapidly removed from the ground water than with prior art methods and residual source areas are removed. It is another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein transport is facilitated and bioavailability of nonaqueous halogenated solvents is enhanced. It is still another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein the method is sustainable for low cost and has low maintenance requirements. It is yet another advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water by adding a composition of matter that is both an electron donor and a surfactant or enhancer of mass transfer. It is still further an advantage of the invention to provide a method for remediation of DNAPLs in ground water wherein destruction of the DNAPLs occurs in situ. It is a yet further advantage of the invention to provide a method for in situ remediation of DNAPLs in ground water wherein an unobtrusive appearance is provided and it meets with public acceptance. These and other advantages can be addressed by providing a method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor enhances mass transfer of the nonaqueous halogenated solvents into solution. The electron donor ideally functions as a surfactant or co-solvent. In cases where the electron donor is a functional surfactant, it is typically added at a concentration above the critical micelle concentration in water. In cases where the electron donor is a functional co-solvent, there may be no critical micelle concentration, or if there is a critical micelle concentration in water, the electron donor is usually added at a concentration below such critical micelle concentration. Illustrative electron donors for use in this method include C 2 -C 4 carboxylic acids and hydroxy acids, salts thereof, esters of C 2 -C 4 carboxylic acids and hydroxy acids, and mixtures thereof. In an illustrative embodiment of the invention, the electron donor is a member selected from the group consisting of lactic acid, salts thereof, lactate esters, and mixtures thereof. Illustrative salts of lactic acid include sodium lactate, potassium lactate, lithium lactate, ammonium lactate, calcium lactate, magnesium lactate, manganese lactate, zinc lactate, ferrous lactate, aluminum lactate, and mixtures thereof. Illustrative targets of the method include nonaqueous chlorinated solvents, such as perchloroethylene (PCE), trichloroethylene (TCE), dichloroethylene (DCE), vinyl chloride (VC), 1,1,1-trichloroethane (TCA), carbon tetrachloride and less chlorinated derivatives thereof, and mixtures thereof. An illustrative aspect of the invention relates to enhancing the reductive dehalogenation activity of indigenous halo-respiring microbes present in the ground water. If halo-respiring microbes are absent or ineffective, then such microbes can be exogenously supplied to the ground water. Illustratively, the microbes are bacteria, such as Dehalococcoides ethenogenes strain 195, the Pinellas culture, and the like, and mixtures thereof. The method degrades the halogenated solvents into innocuous compounds such as ethylene, ethane, carbon dioxide, water, halogen salts, and mixtures thereof. A method for enhancing mass transfer of a nonaqueous halogenated solvent present in a nonaqueous residual source of contamination into the aqueous phase comprises adding to the ground water an effective amount of a composition that donates electrons for reductive dehalogenation of the nonaqueous halogenated solvent and functions as a surfactant for solubilizing the nonaqueous halogenated solvent. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprises adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor comprises an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey or derivative thereof. A method for enhancing in situ bioremediation of a nonaqueous halogenated solvent in ground water comprising adding to the ground water an amount of an electron donor sufficient for a halo-respiring microbe in the ground water to use the nonaqueous halogenated solvent as an electron acceptor, thereby reductively dehalogenating the nonaqueous halogenated solvent into innocuous compounds, wherein the electron donor comprises a mixture of (a) at least about 0.5% by weight of ethyl lactate and (b) at least about 0.5% by weight of a C 2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. An illustrative embodiment of such mixture is a mixture of ethyl lactate and dipropionate, wherein dipropionate is a mixture of propionic acid and sodium propionate. A method for enhancing mass transfer of a nonaqueous halogenated solvent present in a nonaqueous residual source of contamination in ground water, the ground water comprising an aqueous phase, into the aqueous phase comprising adding to the ground water an effective amount of a composition that donates electrons for microbe-mediated reductive dehalogenation of the nonaqueous halogenated solvent into innocuous compounds and functions as a surfactant or co-solvent for solubilizing the nonaqueous halogenated solvent, wherein the composition comprises (a) an aqueous solution of at least about 1% by weight of whey powder or equivalent of liquid whey, or (b) a mixture of at least about 0.5% by weight of ethyl lactate and at least about 0.5% by weight of a C 2 or higher carboxylic acid or hydroxy acid, salt thereof, ester thereof, or mixtures thereof. | 20050124 | 20061128 | 20051201 | 75148.0 | 0 | BARRY, CHESTER T | HALOGENATED SOLVENT REMEDIATION | SMALL | 1 | CONT-ACCEPTED | 2,005 |
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11,042,368 | ACCEPTED | Residential fuel tank monitoring system and proactive replacement program | A data collection and management system is provided for monitoring the condition of fuel tanks and for determining for each tank a degradation profile which provides an estimate of useful tank life and a prediction of when the tank is likely to need replacement before failure. The system is especially useful for monitoring residential fuel tanks and is also applicable for commercial and other tanks which are in a location where a tank failure would be harmful and potentially hazardous. A primary benefit of the system is to allow fuel dealers to identify tanks that should be replaced before they actually fail. The system provides the dealer with information which is useful in monitoring and servicing the fuel tanks of the dealers' customers. | 1. A method for monitoring residential fuel tank condition comprising the steps of: providing a central database containing account information for each owner of a tank being monitored; entering in the database predetermined data factors for each tank relating to the physical and environmental condition of each tank including initial and subsequent measurements of tank wall thickness; processing for each tank the data factors entered in the database to determine a score representing the velocity of change of one or more of the data factors for each tank; and providing an indication based on the score of when each tank needs replacement. 2. The method of claim 1 including the step of providing one or more reports containing tank condition data. 3. The method of claim 2 including the step of providing a report based upon selected data factors to identify the fuel tanks where replacement is needed. 4. The method of claim 1 wherein the entering step includes entering data factors representing the wall thickness of each tank, and the environment in which each tank is located. 5. A method for monitoring residential fuel tank condition comprising the steps of: establishing in a central database an account for each owner of the fuel tanks to be monitored; entering in the central database data on the physical condition of each fuel tank including measurement of tank wall thickness; entering in the central database data on the environment in which each fuel tank is located; processing the data for each tank to determine a score indicating useful tank lifetime and predicted replacement time; and providing an indication based on the score of when each tank needs replacement. 6. The method of claim 5 wherein the data entered in the database includes an initial low test score. 7. The method of claim 6 wherein the data entered in the database includes a current low test score. 8. The method of claim 7 wherein the processing step includes providing a degradation profile index which is the difference between the initial low test score and the current low test score. 9. The method of claim 8 wherein the processing step includes providing a replacement score based upon the degradation profile index and other data entered in the database. 10. The method of claim 9 wherein the replacement score is the difference between the current low test score and an initial replacement standard which is a measure of the rate of change of test scores over time. 11. The method of claim 10 wherein the providing step including providing a report of tanks which need replacement. 12. A method for monitoring residential fuel tank conditions comprising the steps of: establishing a data entry system on a communications network; providing a database in communication with the communications network; establishing an account for a corresponding account holder in the database; entering data via the communications network in the database representing fuel tank conditions for each account holder; and processing the tank data to provide an indication of the useful life of the tank and the predicted replacement time for the tank. 13. The method of claim 12 including the step of establishing from the entered data for each account, information on the condition and installation of the fuel tank associated with that account. 14. The method of claim 12 wherein the communications network is the internet. 15. The method of claim 12 wherein the processing step includes providing an indication of special considerations which denote one or more increased risk conditions for the tank. | CROSS REFERENCE TO RELATED APPLICATIONS N/A STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT N/A BACKGROUND OF THE INVENTION Fuel oil for residential and business heating systems are usually stored in a tank at the premises where the heating system is located. For residential installations the fuel tank is usually located in the basement of a house or outside the home. Deterioration of the fuel tank over time can result in fuel leakage with consequent damage to the premises as well as environmental contamination. Fuel tanks are usually visually inspected by fuel dealers or other service personnel during annual heating system maintenance, but such visual inspection does not reveal many deteriorating tank conditions and does not provide any accurate predictor of tank life. Ultrasonic thickness testers are known for testing the wall thickness of tanks and other vessels; however, such ultrasonic testing has not been applied in a residential application to monitor the condition of fuel oil tanks or to provide data in a systematic way for prediction of the remaining useful lifetime of a fuel tank. It would be beneficial to have a system for predicting the useful lifetime of fuel oil tanks to minimize the likelihood of a fuel tank failure and the consequent cost, damage and hazard which would be occasioned by a fuel spill. Fuel oil dealers typically wait until a tank leaks before replacing it. BRIEF SUMMARY OF THE INVENTION In accordance with the present invention, a data collection, tank analysis and management system is provided for monitoring the condition of fuel tanks and for determining for each tank a degradation profile which provides an estimate of useful tank life and a prediction of when the tank is likely to need replacement before failure. The system is especially useful for monitoring residential fuel tanks and is also applicable for commercial and other tanks which are in a location where a tank failure would be harmful and potentially hazardous. A primary benefit of the system is to allow fuel dealers to identify tanks that should be replaced before they actually fail. The system provides the dealer with information which is useful in monitoring and servicing the fuel tanks of the dealers' customers. The system comprises a computer database management system located at a central computer, and one or more remotely located data entry terminals for entry into the database of applicable data, preferably via an internet or web browser. Typically the data entry terminals, which are usually personal computers, are located at the facilities of fuel dealers who are using the monitoring system. The database is maintained on a server computer disposed at the facility of the provider of the monitoring system. In operation, each dealer having access to the monitoring system, logs on to the provider's web site to gain access to the monitoring system for entry of data for the dealer's customers' fuel tanks and for obtaining reports on the state of each customer's fuel tank. Fuel tank data for each tank is obtained from ultrasonic tank wall testing and from visual inspection of tank installation. Tank testing is performed by dealer service personnel usually during an annual or other periodic service visit to a customer's premises. Testing is accomplished using an ultrasonic thickness gauge to provide indications of tank wall thickness at various locations on the tank. Decreasing wall thickness is a measure of wall deterioration due to corrosion and ultimate failure. The thickness measurements are recorded on a form by the service person and the measurements and other information on tank condition, the environment that the tank is in, certain physical characteristics, certain liability considerations and the like are entered and downloaded from the dealer's computer to the central database where the data is used for providing trend and lifetime information for each fuel tank. Alternatively, the tank measurements as well as other information on tank installation and condition can be directly downloaded to the database using a portable data terminal such as a wireless handheld device. As a further alternative, the data collected during a testing routine can be entered into a data logging device associated with or built into the ultrasonic thickness gauge. This stored data can then be downloaded to the database at a convenient time or the stored data can be downloaded to the dealer computer and then downloaded from the dealer computer to the database at the central computer. The system analyzes, for each tank in the system, data on tank thickness measurements, tank condition, location and other factors to provide indications of useful tank lifetime, and prediction of replacement time for each tank, by creating an individualized replacement standard for each tank based on all the data. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The invention will be more fully described in the following detailed description in conjunction with the drawings in which: FIG. 1 is a diagrammatic illustration of a data communications system in which the invention can be employed; FIG. 2 illustrates an inspection form used in practice of the invention; FIG. 3 shows a web page for use in the invention; FIG. 4 shows a web page for data entry into the system of the invention; FIG. 5 shows a web page for entering data; FIG. 6 shows another web page for entry of data; FIG. 7 shows a web page for review of entered data; FIG. 8 is a flowchart illustrating system operation; FIG. 9 shows a report of selected data; FIG. 10 shows another report of selected data; FIG. 11 shows a report of failed tank data; FIG. 12 shows a report listing sortable data points; FIG. 13 shows a report listing customer accounts; and FIG. 14 shows a listing of acronyms and nomenclature utilized in the system reports. DETAILED DESCRIPTION OF THE INVENTION In a preferred business model, the monitoring system is operated by a service provider which maintains a server computer containing database management software at its facility. Customers of the service provider are usually fuel oil dealers or HVAC companies who are provided access to the monitoring system via the dealer's own computer which communicates with the service provider's central computer via the Internet. Referring to FIG. 1, there is shown a central computer 10 having a database 12 and which can communicate with dealer computers via the Internet 14 or other data network. A plurality of dealer computers 16 are connectable via the Internet for data communication with central computer 10. A data device 18 can also be in communication with the central computer 10 via the Internet. The data device can be for example, a wireless data device such as a handheld data terminal. The dealer computers are usually personal computers having a browser for Internet access. The central computer can also be a personal computer or server having sufficient data storage and speed to suit intended system performance requirements. The monitoring system software is contained in the database 12 of the computer 10. The system software can be implemented utilizing database management software such as Microsoft Access. It will be recognized that the computers are operating in a client-server mode for communication of data from the dealer computers to the central computer, and from the central computer to the dealer computers. Other data communication modes can be employed including data networks other than the Internet, and other wired and wireless data networks and data links. The acronyms and nomenclature described herein are set forth in FIG. 14. Data on the fuel tanks of the fuel dealer's customers is obtained by the dealer's service technicians. During a visit to the customer's premises at which a tank is located, the technician obtains data on the particular tank, including the gauge of the tank, and performs ultrasonic testing of the tank to provide measurements of tank wall thickness. In the North American market fuel oil tanks for residential installations are usually 12 gauge and 14 gauge. A 12 gauge tank has a wall thickness of approximately 0.1 inch, and a 14 gauge tank of approximately 0.078 inch. For each tank to be monitored, an ultrasonic thickness test is performed at the top of the fuel oil storage tank which is an area not likely to be affected by corrosion, and these measurements are employed to confirm the tank gauge. A typical ultrasonic thickness gauge utilized to provide thickness measurements is the Dakota Ultrasonics MX-1, which is a small handheld unit readily transportable by a service technician. The bottom of the fuel oil storage tank is also tested at random sample points, typically on either side of the bottom center line of the tank, to provide a number of test scores and to determine an Initial Low Test Score (ILTS) as a benchmark for the tank during its first year of monitoring. The location where the low test score was found is also identified and will be tracked during the monitoring process. The tank test is repeated each year or other periodic interval, and successive annual tests are stored by the system and provide a historical record. The Current Low Test Score (CLTS) represents the lowest annual test score for the latest test. The scores provide a comparison and a basis to measure both the velocity and distance or extent of tank degradation due to corrosion. Additional data is obtained by the service technician during inspection of each tank to create reports on tank lifetime and predicted replacement time. Data for each tank relates to the environment the tank is in, the physical characteristics of the tank, the distance and velocity of tank degradation based on the ILTC and CLTS and certain other considerations as further discussed below. A typical tank inspection form is illustrated in FIG. 2. Customer name and address information is provided, as is tank information including tank gauge. The tank gauge test score as determined from measurements at the top of the tank is provided to verify the tank gauge which is important in determining degradation measurements for the appropriate gauge. The feed type is noted to identify whether the fuel feed is on the bottom, side or top of the tank. The tank type is also noted to identify whether the tank is an upright or flat style of tank. The fuel oil capacity of the tank is specified as is the tank manufacturer. The form also notes the distance of the tank from the wall, whether the feed line is in concrete or not, whether the tank is exposed to saltwater and whether the tank is located in a seasonal residence. For outside locations, the form notes whether or not the tank is on a mounting pad and whether or not there are any hazards in the location and what the hazard is. For example, a hazardous condition could be that a tree limb has grown over the proximity of the tank. The inside location data notes whether the tank is on a dirt floor or in a finished basement and the condition (wet or dry) of the basement. The form also notes the lowest ultrasonic thickness reading and location of the lowest reading represented by the location positions as shown on the tank diagram on the form. The pass/fail status of the tank is noted as is any comment on potential code violations such as an undersized ventilation pipe. A number of data factors are identified and can be selectively specified for use in monitoring each tank and for determining and predicting potential failure. Each tank to be part of the monitoring program, must qualify by having a minimum test score of 0.081 inch for a 12 gauge tank and 0.07 inch for a 14 gauge tank. If the initial low test score is below these numbers, that tank would not qualify for the monitoring program as the condition of the tank is sufficiently deteriorated as to need prompt replacement. If the tank fails the initial test, the customer is notified of the tank test failure and is provided with a recommendation to promptly replace the tank. Information on the failed tank is entered into the system to provide a record of non-qualified tanks for which follow up actions can be taken by the dealer. If the tank passes the qualification test, the data on the inspection form is entered into the monitoring system. Data from the inspection form is keyed into the dealer's computer and transmitted to the monitoring system using an Internet connection between the dealer's computer and the service provider's computer. The dealer accesses the monitoring system by logging into the service provider's web site using the dealer's e-mail name and password. After login, the system prompts a user through the steps for use of the system. Various pages or screens are shown in FIGS. 3 through 7 for the monitoring system. The introduction page shown in FIG. 3 identifies the functions which can be performed and the forms which can be generated by the system. The Enter Reading function permits entry of tank information for new customers, editing of customer accounts and adding of new test scores for existing customers. The Account list provides a view of customers enrolled in the program and which can be sorted by various parameters. The Data Trend report provides a report of tanks being monitored, with those tanks being flagged for proactive replacement based upon the data analysis provided by the system. Specialized reports based on a variety of sorting features can also be generated. A Renewal report can be provided to provide a list of customers that require a new reading in a specified time period. The system can also generate, upon request, an inspection form and a warranty certificate for a customer. The data entry sequence is shown in FIGS. 4 through 7. As an initial step, the account number for the particular fuel tank is entered as shown in FIG. 4. In the next step, the screen of FIG. 5 appears for entry of customer information and tank information as shown in the entry form. After this form has been completed the next form appears as shown in FIG. 6 which calls for entry of ultrasonic test readings. The next screen is shown in FIG. 7 which presents the entered information for review and verification. Upon completion of the entry sequence, the data is stored in the database for the associated customer account. If a tank does not qualify in accordance with the qualifying criteria, as noted above, a notice is generated by the system and is sent to the customer to warn of the potential tank failure and to recommend that the tank be promptly replaced. If the tank qualifies in accordance with the qualifying criteria, as noted above, the system can generate a warranty certificate which is sent to the customer to provide a written warranty and conditions of warranty for the tank enrolled in the monitoring program provided by the system. A flowchart of system operation is illustrated in FIG. 8. An initial tank test is performed in step 80 and test and other data relating to the tank are entered in step 82 using the dealer computer or other data entry device, and stored in the central computer at step 84. The central computer 10 performs data analysis in step 86 and is operative to provide various reports as described herein. At each new year or other periodic interval, updated tank tests are performed in step 88 and this updated data is entered and stored as described above. Various management reports 90 can be provided from the data analysis. The data analysis can also provide a Flagged tank report 92 such as shown in FIG. 11, to denote all of the monitored tanks which have failed the testing. A Special Considerations report 94 can also be generated to identify monitored tanks which are not sufficiently deteriorated to be “flagged” for replacement but which are considered to be at risk for failure because of particular circumstances to be described below. The tanks identified in either of the reports 92 or 94 can be subject to a replacement notice 96 which is sent to each tank account customer as a notification that the tank is recommended for replacement. The tank data entered into the system database is available to each dealer via the Internet connection for review of customer data by the dealer and for obtaining reports on customers and tank profiles based on various selection criteria which can be specified by the dealer. The system can respond to the selection criteria to issue the appropriate report and information contained therein. Another report provides a listing of those tanks that have been disqualified and for which replacement has been recommended. This report can be utilized for follow up by the dealer with those customers for whom tank replacement has been recommended. A Data Trend report is shown in FIG. 9 and provides a list of account numbers and customer names with initial and current low test scores for the respective fuel tanks, and a Degradation Profile Index (DPI) which is the difference between the ILTS and the CLTS. The Individual Replacement Standard (IRS) provides a measure of the velocity of change in the test scores. The IRS value is computed by the system based upon a variety of factors including the velocity of degradation, gauge of the tank, feed line position, the environment in which the tank is located, and certain liability factors. For example a tank that is located in a dirt floor basement vs. a cement floor basement, etc. A Replace value is computed based on the difference between CLTS and IRS, a negative difference value being is an indication that the tank should be replaced. The replacement status is indicated by a flag symbol next to the respective Replace values. Thus, the system provides, for each tank, an estimate of useful tank life and a prediction of when the tank is likely to need replacement before tank failure. The inspection form shown in FIG. 2 sets forth the data factors employed to generate the Individual Replacement Standard (IRS) and to specify the factors which can be selectively sorted to identify Flagged tanks, or Special Considerations or other conditions to be sorted and reported. Each of the factors has an assigned numerical value stored in the system database and which is utilized by the system to compute an IRS value for the associated tank. This IRS value is subtracted from the CLTS to yield a Replace score for that tank. If the Replace score is negative, the tank is flagged for replacement. It will be appreciated that the system takes into account all of the relevant factors which can affect useful tank lifetime. These factors relate to the tank itself, and to the environment in which the tank is located. In the following example a 12 gauge tank is in a wet basement, and has a side feed that is within 2 inches of a wall, and a DPI of 0.005. Profile Description: 12 Gauge Tank: 0.065 14 Gauge Tank: 0.05 Outside Tank: 0.002 Side or Top Feed: 0.005 Inside Dirt Floor: 0.005 Finished Basement: 0.005 Distance from Wall<2: 0.004 Exposed to Salt Water: 0.006 Wet Condition: 0.002 The IRS=0.065+0.002+005+004+0.005=0.081 Replace Score=CLTS−IRS In this example, the system is considering key factors that relate to the tank's individual risk and failure profile characteristics. These include physical characteristics like gauge and location of feed line, environmentally related influences like being in a wet basement and having a lack of “breathing space” between the tank and adjacent wall, and the tank's degradation profile and the velocity of that degradation based on a series of annual ultrasonic test scores. All of these factors will contribute over time to the tank's required replacement. The IRS is a “fluid” value and may change year over year based on the annual ultrasonic test and changes in the DPI relating to the Current Low Test Score. The tank is flagged when the Replace score is a negative number. The lower the Replace score the worse the tank condition is. Some tanks can be identified by a C code to designate that there are comments for this tank. The comments can be that there is a building, fire or other regulatory code requirement to be addressed. Some tanks can be identified by an H code which identifies a hazardous condition near the tank, such as tree limbs overhanging an outside tank. These codes C and H can be shown next to the account number as illustrated in FIGS. 9 and 10. A report of accounts having C and/or H designations can be generated to identify those accounts where corrective actions are needed. FIG. 10 shows a report which identifies only seasonal residences and the tank data for those residences. These tanks may be a greater liability since the residence is unoccupied for much of the year, and thus a fuel leak may go undetected. The tanks in the seasonal residences are identified by their test scores to be monitored on a more frequent basis and owners notified of risk conditions. The report shown in FIG. 11 lists only failed tanks that did not pass the inspection and that should be replaced or are near replacement. The report illustrated in FIG. 12 lists various selection characteristics which can be specified to provide a selective data sort to identify tanks meeting the selection criteria. The resulting data is used for analysis of the listed tanks so that appropriate action may be taken in suggesting replacement or other tank service. The system can also provide a report which lists all accounts that are part of the monitoring program, and such a report is illustrated in FIG. 13. This report shows account number, name and address of each account holder, the date when the account started, and the date of the last tank reading. Each account entry can be edited or the account can be read or opened to see the associated data for the monitored tank of that account. As noted above, tanks can be identified as having “Special Considerations” and which can be proactively replaced based on specific data characteristics. A tank may not yet be identified as a Flagged Tank that needs replacement, but is identified as a “Special Considerations” candidate which is considered to be at risk for failure because of certain circumstances. Data can be sorted by a search category called Within a Hundredth of an Inch (WHI). This category selects those tanks in the database that are in a range of 0.001-0.009 in the Replace category and which represents a marginal condition for tanks having certain predetermined conditions. A “Special Considerations” can, for example, be a tank that has a Replace score of 0.001 and that is at risk as being in a seasonal residence where no one is home for months of a year, or a home with a dirt floor basement where oil can leak into the ground. Various other reasons can be specified for use in determining a “Special Considerations” category for the monitored tanks, such as a tank requiring considerable code upgrades that also is in the WHI category. The system provides management reports for the dealer to improve the efficiency and quality of service that can be provided to customers and to identify those tanks requiring replacement or other attention before leakage may occur. As an example, a service technician can be directed, based on data from the system to inspect a seasonal home tank before the resident leaves for the off season. The system can also provide data to track hazards such as tree limbs growing over outside tanks and to identify code upgrade requirements, such as a tank with poor support legs. The system also can identify those tanks for which the service schedule should be adjusted or for which various other corrective actions should be taken. The system provides an extremely versatile management tool for fuel oil dealers, HVAC contractors and the like to track the conditions of customers' fuel tanks and provide proactive information on tank replacement and remediation of other potentially hazardous or damaging conditions. The invention is not to be limited by what has been particularly shown and described. It will be appreciated that alternative implementations will occur to those of skill in the art without departing from the spirit and true scope of the appended claims. | <SOH> BACKGROUND OF THE INVENTION <EOH>Fuel oil for residential and business heating systems are usually stored in a tank at the premises where the heating system is located. For residential installations the fuel tank is usually located in the basement of a house or outside the home. Deterioration of the fuel tank over time can result in fuel leakage with consequent damage to the premises as well as environmental contamination. Fuel tanks are usually visually inspected by fuel dealers or other service personnel during annual heating system maintenance, but such visual inspection does not reveal many deteriorating tank conditions and does not provide any accurate predictor of tank life. Ultrasonic thickness testers are known for testing the wall thickness of tanks and other vessels; however, such ultrasonic testing has not been applied in a residential application to monitor the condition of fuel oil tanks or to provide data in a systematic way for prediction of the remaining useful lifetime of a fuel tank. It would be beneficial to have a system for predicting the useful lifetime of fuel oil tanks to minimize the likelihood of a fuel tank failure and the consequent cost, damage and hazard which would be occasioned by a fuel spill. Fuel oil dealers typically wait until a tank leaks before replacing it. | <SOH> BRIEF SUMMARY OF THE INVENTION <EOH>In accordance with the present invention, a data collection, tank analysis and management system is provided for monitoring the condition of fuel tanks and for determining for each tank a degradation profile which provides an estimate of useful tank life and a prediction of when the tank is likely to need replacement before failure. The system is especially useful for monitoring residential fuel tanks and is also applicable for commercial and other tanks which are in a location where a tank failure would be harmful and potentially hazardous. A primary benefit of the system is to allow fuel dealers to identify tanks that should be replaced before they actually fail. The system provides the dealer with information which is useful in monitoring and servicing the fuel tanks of the dealers' customers. The system comprises a computer database management system located at a central computer, and one or more remotely located data entry terminals for entry into the database of applicable data, preferably via an internet or web browser. Typically the data entry terminals, which are usually personal computers, are located at the facilities of fuel dealers who are using the monitoring system. The database is maintained on a server computer disposed at the facility of the provider of the monitoring system. In operation, each dealer having access to the monitoring system, logs on to the provider's web site to gain access to the monitoring system for entry of data for the dealer's customers' fuel tanks and for obtaining reports on the state of each customer's fuel tank. Fuel tank data for each tank is obtained from ultrasonic tank wall testing and from visual inspection of tank installation. Tank testing is performed by dealer service personnel usually during an annual or other periodic service visit to a customer's premises. Testing is accomplished using an ultrasonic thickness gauge to provide indications of tank wall thickness at various locations on the tank. Decreasing wall thickness is a measure of wall deterioration due to corrosion and ultimate failure. The thickness measurements are recorded on a form by the service person and the measurements and other information on tank condition, the environment that the tank is in, certain physical characteristics, certain liability considerations and the like are entered and downloaded from the dealer's computer to the central database where the data is used for providing trend and lifetime information for each fuel tank. Alternatively, the tank measurements as well as other information on tank installation and condition can be directly downloaded to the database using a portable data terminal such as a wireless handheld device. As a further alternative, the data collected during a testing routine can be entered into a data logging device associated with or built into the ultrasonic thickness gauge. This stored data can then be downloaded to the database at a convenient time or the stored data can be downloaded to the dealer computer and then downloaded from the dealer computer to the database at the central computer. The system analyzes, for each tank in the system, data on tank thickness measurements, tank condition, location and other factors to provide indications of useful tank lifetime, and prediction of replacement time for each tank, by creating an individualized replacement standard for each tank based on all the data. | 20050125 | 20070102 | 20060727 | 70193.0 | G06F1130 | 0 | SUAREZ, FELIX E | RESIDENTIAL FUEL TANK MONITORING SYSTEM AND PROACTIVE REPLACEMENT PROGRAM | SMALL | 0 | ACCEPTED | G06F | 2,005 |
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