PATENT ABSTRACT
An improved method and apparatus for vending products, and particularly beverage containers, of varied sizes, shapes and configurations without dropping or subjecting the vended product to damaging impact forces are disclosed. The products to be vended are aligned in selectable ordered queues within a vending machine that can include a transparent front panel. A robotic carriage assembly using rack and pinion assemblies moves in positive non-vibratory manner along an X-Y plane in the machine, captures the selected product from its queue and smoothly transports the product to a product delivery port conveniently located close to hip level. The carriage assembly uses unique product escapement and capture mechanisms to smoothly slide the related product from its queue into the carriage. Power door and safety lock features at the delivery port are also disclosed.

PATENT DESCRIPTION
This application is a continuation-in-part application of U.S. patent application having Serial No. 08/949,366, filed Oct. 14, 1997, now U.S. Pat. No. 6,230,930 the entire disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to vending machines, and more particularly to an improved method and apparatus for vending multi-sized and fragile products and in particular bottled or canned beverages of varied sizes and shapes. 
     BACKGROUND OF THE INVENTION 
     This invention applies to the vending of products in general and in particular to the difficult issues that arise when attempting to dispense items of various sizes and shapes and/or fragile items that do not fare well when subjected to dropping or impact forces during a vend cycle. While the invention addresses all of these issues, the problems associated with dispensing bottled beverages of various sizes and configurations and packaged in various types of materials such as glass or plastic perhaps best characterize the situation. Accordingly, the invention will hereinafter be discussed in the context of its applicability to dispensing contained beverages, it being understood that the inventive principles can be expanded to include the dispensing of other products as well. 
     Machines for vending canned and/or bottled beverages have long been known. Early bottled vending machines enabled release of same-sized bottled beverages, one at a time, following deposit of the required purchase amount, from chest-like coolers. The purchaser was required for example to slide the neck of the beverage bottle along and through a retaining race to a dispensing location from which it could be lifted out of the refrigerated chest after release by the dispensing mechanism. With the advent of canned beverages, dispensing became somewhat simpler and easier to automate due to the standardization of container sizes and techniques that enabled the cylindrical cans to roll and drop through chutes during a vend cycle to the delivery area of the machine. Due in part to the rigidity of the cans and their secure seal mechanisms, and the fact that their movement can be fairly well controlled during a dispensing cycle, the canned beverage vending machine has become the standard of today&#39;s sealed beverage dispensing systems. 
     For the most part, the sale of specialty beverages such as fruit or fruit flavored juices, milk, teas and the like and/or beverages that were sealed in glass or plastic bottles, has been conducted by over-the-counter sale techniques and not through automated vending machines. For many of such specialty beverages, packaging in the standard disposable can configuration is not a viable option. For others, the marketing appeal and distinctiveness of a uniquely shaped or stylized container is of major concern. Non-can packaging has now even become popular for the well-known carbonated beverages, that are readily available in many different sized and shaped containers, both plastic and glass, and in various volumes. 
     It has also become desirable for vending machines to have glass doors through which the actual product being vended can be viewed by the purchaser. Such machines having helical vending coils (as for example illustrated in U.S. Pat. No. 4,061,245) for dispensing non-beverage packaged goods have become very popular with both customers and merchants. Refrigerated merchandising coolers for holding bottled beverages and having glass fronts have also been available in, for example, convenience stores, but have not generally been available for automatic dispensing of beverages. Some beverage dispensing machines have been configured such that their front doors hold actual samples of the beverages contained within the machine, but do not display the actual beverages to be dispensed. 
     Whether or not the vending machine has a glass front, automated vending has been a problem for most of the non-standard sized and non-canned beverage containers. To date, an automated vending machine that can reliably and safely vend beverage containers of different materials, sizes and shapes from the same machine, without damaging or dropping the container or product within has not been available. 
     One beverage vending machine that has attempted to address the need for a glass front beverage vending machine for bottled-type containers is illustrated in U.S. Pat. Nos. 5,505,332 and Des. 362,463. Such machine enables the purchaser to view and select the actual product to be vended, but operates on a principle that vertically drops the vended beverage container from the front end of the shelf on which it is stored, to a lower chute area that redirects the container to a delivery area from which the purchaser can remove the container. While addressing a number of industry needs, this vending technique is not usable or practical for vending many of the varied shaped and sized beverage containers available today, without the risk of damage to the container or contents. This is particularly true of larger glass bottles or thinner plastic containers that are susceptible to breakage or damage during a vertical drop vending process. In order to address such problems, larger and/or more damage susceptible containers, might be required to be placed on the lowermost shelves of the machine in order to minimize the vertical drop distance. Such requirement can impose significant marketing disadvantages to the merchandisers of such products who may wish to have their products displayed at a higher (e.g. eye level) position in the machine. Further, the impact imparted to the beverage container and its contents as a result of the vertical drop process can result in explosion or ruptured containers. At the very least, for carbonated beverages, the drop vend process requires the purchaser to wait for a period of time before opening the container in order to prevent explosive or overflow effervescence of the beverage upon opening. It is obvious that any breakage or product leakage or explosion within the vending machine can be very detrimental to the operability and reliability of the machine and can contribute to excessive maintenance problems. 
     Another disadvantage of machines such as that of the U.S. Pat. No. 5,505,332 patent, and virtually all vending machines that operate on the principle of dropping and delivering the vended product by gravity, is that the delivery bin or delivery port of the machine is necessarily located below the lowest shelf of the product storage area toward the lower portion of the machine. Such positioning requires the purchaser to bend down and often to reach in awkward manner, in order to retrieve the vended product from the delivery bin of the vending machine. 
     There have been designs of vending machines that use robotic principles to acquire a product to be vended from the machine. With the use of such robotic techniques, the product to be vended can be selected and removed from its stored position without dropping the product, and which can then be carried to a delivery area that is not required to be at the bottom of the machine. Examples of such machines as applied to the vending of like-sized video cassettes are illustrated by U.S. Pat. Nos. 5,036,472 and 5,139,384. Such systems, however, have not been particularly applicable to the dispensing of fragile products or of beverage containers of varied shapes. In general they have employed robotic mechanisms that are not practical for rapidly dispensing beverage, containers, and do not generally address the other problems of the prior art described above as related to dispensing bottled beverages. 
     The present invention addresses the described deficiencies of prior art vending machines and the need for a dispensing machine and method for dispensing fragile containers such as beverages packaged in glass, plastic or can containers of varied sizes, shapes and fluid volumes. 
     SUMMARY OF THE INVENTION 
     This invention provides an improved vending machine apparatus and method for vending products, and particularly bottled and canned beverages, without subjecting the vended containers to shock and impact forces due to dropping, rolling or abrupt tipping of the product during the vending operation. The invention uses an efficient, cost-effective, highly accurate, reliable and easily programmable robotic beverage capture assembly for capturing that beverage container selected by a customer from a plurality of viewable stored containers and for smoothly, gently, and quickly carrying the captured container to a product delivery area or port of the machine. The product delivery port is located at thigh to waist height to minimize customer bending while retrieving the vended product from the machine. The shelf or tray area of the machine preferably contains no active or powered components, but is entirely passive in nature, being operated entirely in response to activation forces applied thereto by the robotic beverage container capture apparatus. The vending machine and apparatus is extremely versatile and is particularly applicable to the vending of glass and plastic beverage containers of varied sizes, shapes and fluid volumes which can simultaneously be housed and dispensed by the vending machine. The glass door of the vending machine enables point-of-sale marketing of the products to be vended and allows the consumer to view the selected vended product during virtually the entire vend cycle. The smooth vending process minimizes product damage and stress and virtually eliminates machine maintenance caused by damage to or breakage of beverage containers during a vend cycle. 
     Thus according to one aspect of the invention there is provided a method for vending beverages packaged in sealed containers, comprising the steps of: (a) storing a plurality of packaged beverages and selectable queues of containers of such beverages within a vending machine; (b) aligning a robotic assembly in the machine in registration with a consumer selected one of said beverage container queues; (c) transferring one of the beverage containers from the selected container queue to the robotic assembly; (d) carrying the transferred beverage container to a delivery port of the vending machine; and (e) presenting the carried beverage container at the delivery port for customer removal from the vending machine; wherein the entire process is performed without dropping or subjecting the container to severe impact forces. The product queues can be arranged in vertically spaced columns within the vending machine which can be readily adjusted to accommodate beverage containers of varied heights. Further, the beverages can be arranged on shelves or trays that can be inclined at angles which permit gravity movement of the stored beverages in the queues toward a dispensing end of the queue. According to a preferred aspect of the invention, the customer selected beverage container is transferred from the selected container queue to the robotic assembly by simply sliding the first-in-line container from the selected queue into retaining engagement by the robotic assembly, while retaining the second-in-line and successively aligned ones of the beverage containers in that queue from moving along the queue. 
     According to yet another aspect of the invention there is provided a method of vending bottled beverages from a vending machine of the type having a transparent front viewing panel that enables customer viewing of the actual beverages held by the machine and available for vending, comprising the steps of: (a) aligning a plurality of bottled beverages in at least two ordered queues of the beverages; (b) providing a customer selection input identifiable with at least one of the two ordered queues of beverages; (c) removing a bottled beverage from said one of said ordered queues in response to said customer selection input; and (d) moving the removed bottled beverage to a delivery port of the machine, wherein the removing and moving steps are smoothly performed without dropping or subjecting the bottled beverage to sharp impact forces. 
     According to yet another aspect of the invention there is provided a method of vending discrete products from a vending machine of the type having a transparent viewing panel for customer viewing and selection of the products to be vended, and a support for supportably holding the products for visual presentation to a customer through the viewing panel, comprising the steps of: (a) ordering the products in a plurality of selectable queues of the products on the support such that a foremost one of the products in each of the queues addresses the viewing panel at a dispensing end of its associated queue; (b) moving a capture assembly into alignment with a dispensing end of a customer selected one of the queues; (c) transferring the foremost one of the products from the customer selected one of the queues into retainment by the capture assembly; (d) moving the capture assembly with its retained product in view of the viewing panel to a delivery port; and (e) enabling customer removal of the retained product from the capture assembly at the delivery port; wherein the steps of transferring and moving the foremost product from the selected queue to the delivery port are performed without dropping or subjecting the foremost product to sharp impact forces. 
     According to yet a further aspect of the invention there is provided a vending machine for beverages packaged in sealed containers, comprising: (a) a storage facility defining an enclosed internal cavity and a container delivery port opening into the internal cavity; (b) a container holder within the internal cavity for holding a plurality of selectable sealed beverage containers, wherein the container holder is disposed to define with the storage facility a vend selection space within the internal cavity; (c) a beverage container capturer for retainably removing one of the plurality of selectable beverage containers from the container holder in response to a vend control signal; (d) transport means operatively connected with the beverage container capturer for moving the beverage container capturer within the vend selection space in response to the vend control signal; and (e) a control system operatively connected with the capturer and with the transport system for producing and providing the vend control signal thereto to cause the capturer and the transport system to cooperatively capture a selected beverage container from the container holder and smoothly carry the captured container through the vend selection space to the delivery port without dropping or subjecting the selected beverage container to sharp impact forces. The invention further contemplates the use of a door forming a part of the chassis and including a transparent panel for enabling customer viewing of the plurality of selectable beverage containers in the chassis. The invention further contemplates the use of container releaser operatively connected with at least one of the queues adjacent its discharge end for selectably retaining the beverage containers in the queue. The container releaser preferably includes only passive components which do not require any external energy sources. The invention further includes a plurality of trays for aligning the containers in their respective queues. According to a further aspect of the invention, the transport system includes a rack and pinion system for moving the beverage container capturer in the vend selection space in an accurate, positive and smooth manner, without vibration or wobble. 
     According to yet a further aspect of the invention there is provided a vending machine for vending selectable products comprising: (a) a product storage chassis including a door, cooperatively forming an internal cavity, wherein the chassis includes a transparent panel portion to enable viewing therethrough into the internal cavity and a product delivery port spaced from the transport parent panel portion; (b) product selection system operable by a customer for generating a vend control signal indicative a product selection of the customer; (c) a support operatively mounted within the internal cavity of the product storage chassis for supporting the products in a plurality of selectable and separate ordered queues of such products; and (d) a robotic assembly mounted to the chassis and operatively moveable within the internal cavity in response to the vend control signal to rapidly and smoothly remove and carry a selected product from its associated ordered queue to the product delivery port, without dropping or jarring the selected product; wherein a customer can view the entire product removal and carrying operation of a vending cycle of the machine through the transparent panel portion. The invention further contemplates the positioning of the delivery port at a customer convenient height that does not require the customer to excessively bend to retrieve the vended product. According to a further aspect of the invention, a door and associated locking assembly are provided at the delivery port for preventing opening of the door unless a vended product is available at the delivery port, and for preventing movement of the robotic assembly whenever the door is enabled for opening. The invention further contemplates the use of a robotic assembly having an X-Y support frame mounted in the chassis; a shuttle moveably mounted to the support frame for movement therealong in an X-direction; a carriage assembly operatively connected to the shuttle for controlled movement therealong in a Y-direction; and a capture mechanism operatively mounted to the carriage assembly for removing and carrying the selected product from its associated ordered queue. According to a preferred embodiment of the invention, dc motors with output drive gears engaging rack members are used for energizing the robotic assembly. 
     According to a further aspect of the invention there is provided a carriage assembly for use with the vending machine of the type having: a chassis defining an internal cavity, a front door forming one side of the chassis; a product support assembly mounted in the chassis and configured to hold a plurality of products to be vended in separate ordered queues of the products, such that one end of the queues address a dispensing end of the product support assembly, wherein the volume between the dispensing ends of the product support assembly and the door define a vend selection space; wherein the carriage assembly comprises: (a) an X-rail assembly mounted to the chassis in generally horizontal orientation; (b) a Y-rail assembly mounted to the X-rail assembly in generally vertical orientation and configured for movement along the X-rail assembly; (c) an X-drive motor mounted for movement with the Y-rail assembly for controlling movement of the Y-rail assembly along the X-rail assembly; (d) a carriage mounted to the Y-rail assembly for movement therealong; (e) a Y-drive motor mounted for movement with the carriage for controlling movement of the carriage along the Y-rail assembly; and (f) wherein the carriage assembly is configured to accurately move, position and hold the carriage relative to the product support assembly within the vend selection space. According to a preferred configuration of the carriage assembly, the carriage can attain movement positioning and positional maintenance along the Y-rail assembly to within an accuracy of {fraction (1/32)} inch and even to within an accuracy of {fraction (1/64)} inch. Accurate positioning of the carriage assembly in both the X and Y-directions is achieved by position sensors. 
     According to yet a further aspect of the invention there is provided a product release and capture assembly for use in a vending machine of the type having: a chassis defining an internal cavity; a product support assembly mounted in the chassis and configured to hold a plurality of products to be vended in separate ordered queues of the products, said product support assembly being arranged and configured to define a dispensing end of the queues, wherein a vend selection space is defined in the internal cavity adjacent the dispensing ends of the queues; the product support assembly further including means for urging products in the queues to move toward the dispensing ends of the queues; a carriage; a drive system connected to controllably move the carriage generally in an X-Y coordinate plane within the vend selection space into alignment with the dispensing end of a selected one of the product queues, wherein the product release and capture assembly comprises: (a) an escapement mechanism mounted to the product support assembly of the selected one of the product queues adjacent the dispensing end thereof, wherein the escapement mechanism comprises: (i) a first engagement member configured to selectively engage a first-in-line product at the dispensing end of the selected queue; (ii) a second engagement member configured to selectably engage a second-in-line product aligned in said queue immediately adjacent to and behind the first-in-line product; (iii) a connector operatively connecting the first and second engagement members for cooperative movement, wherein the connector is configured to move the first engagement member into engaging and disengaging positions relative to the first-in-line product while simultaneously respectively moving the second engagement member into disengaging and engaging positions relative to the second-in-line product; (iv) bias means operatively connected with the connector for normally moving the first engagement member into its engaging position; and (v) a force receiving surface operatively connected with the connector for receiving an activating force tending to move the connector against the normal bias of the bias means; and (b) a capture receptacle movably mounted to the carriage for movement between first and second positions; the said capture receptacle when operable in said first position enabling free movement of the capture receptacle and the carriage relative to the escapement mechanism in the vend space; and being operable when moving to said second position, and when the carriage is positioned in operative alignment with a dispensing end of the selected queue, to engage the force receiving surface to operatively move the connector against the bias of the bias means, to move the first engagement member toward its disengaging position, thereby releasing the first-in-line product for movement out of the dispensing end of the queue and into the capture receptacle. According to yet a further aspect of the invention, the connector slidably engages the first engagement member and the connector and first engagement member are independently pivotally mounted for movement relative to one another. According to yet a further aspect of the invention, the first engagement member extends through a slot in the connector. According to yet a further aspect of the invention, the escapement mechanism includes only passive components requiring no power energy sources. According to yet a further aspect of the invention, the capture receptacle is pivotally mounted to the carriage about a generally horizontal pivot axis and pivotally moves thereabout to activate the escapement mechanism. The capture receptacle includes a floor portion for supporting one of the captured products from the queue and is configured such that its floor portion aligns with the queue floor portion during the vend procedure. The capture receptacle may also include retainer in the floor and a stabilizer for maintaining the captured products in a stable position during its transport phase to the product delivery port. 
     These and other aspects of the invention will become more apparent upon a description of a preferred embodiment of the invention. It will be appreciated that the preferred embodiment is not to be construed as limiting the invention to any particular configurations, designs, or applications that are specifically presented therein. The preferred embodiment is presented to illustrate a specific application and implementation of the broader principles of the invention and is not to be construed in a limiting manner. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     Referring to the Drawing where like numerals represent like parts throughout the several views: 
     FIG. 1 is a front elevational view of a preferred embodiment of a beverage container vending machine incorporating the principles of the invention; 
     FIG. 2 is an enlarged front elevational view of the inner beverage tray assembly of the vending machine of FIG. 1, also illustrating the robotic beverage capture assembly of the vending machine; 
     FIG. 3 is a right side elevational view of the tray assembly and robotic beverage capture assembly of FIG. 2; 
     FIG. 4 is a top, right, front perspective view of the support frame structure of the vending machine of FIG. 1 with the outer chassis and door removed, illustrating the robotic beverage capture assembly attached thereto, and one vertical support beam of the beverage tray assembly of FIGS. 1 and 2; 
     FIG. 5 is an enlarged fractional front elevational view of the upper rail portion of the robotic beverage capture assembly disclosed in FIGS. 2,  3 , and  4 ; 
     FIG. 6 is a right elevational view of the upper rail assembly of FIG. 5; 
     FIG. 7 is an enlarged fractional front elevational view of the lower rail portion of the robotic beverage capture assembly disclosed is FIGS. 2,  3 , and  4 ; 
     FIG. 8 is a cross-sectional view of the lower rail assembly of FIG. 7, generally taken along the Line  8 — 8  of FIG. 7; 
     FIG. 9 is an enlarged fractional perspective view of the beverage capture cage portion of the robotic beverage capture assembly of FIGS. 2,  3 , and  4 ; 
     FIG. 10 is an exploded view of the beverage capture cage assembly of FIG. 9; 
     FIG. 11 is an enlarged fractional perspective view of the front end of a beverage try illustrating a preferred configuration of a release mechanism in operative position relative to a beverage container; 
     FIG. 12 is a diagrammatic side view illustrating movement of the beverage capture cage portion of the robotic beverage capture assembly during a vend cycle; 
     FIG. 13 is a diagrammatic top view illustrating the sequential movement of the container release mechanism during a vend cycle; 
     FIG. 14 is an enlarged top, front, right side perspective view of the delivery door assembly of the vending machine of FIG. 1; 
     FIG. 15 is a top, right, back side perspective view of the door assembly of FIG. 14; 
     FIGS. 16A and 16B form a schematic diagram illustrating the various components of the vending machine and their functional relationship and interaction; 
     FIGS. 17A and 17B form a flow chart illustrating various operations performed by the vending machine under computer control during a vend cycle; 
     FIG. 18 is a top perspective view of a floor insert member for use with the beverage capture cage; 
     FIG. 19 is a top view of a low surface friction floor insert of a beverage tray; 
     FIG. 20 is a cross section end view of the floor insert of FIG. 19; and 
     FIG. 21 is an enlarged side perspective view of a lever guide arm. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the figures there is generally illustrated therein a preferred embodiment of a vending machine that incorporates the principles of this invention. While the preferred embodiment of the invention will be described in association with its applicability to a vending machine for bottled and canned beverages, it will be understood that the broad principles of the invention are not limited to such product dispensing application or to the specifics of the preferred embodiment machine disclosed. The described machine represents one clear example of a dispensing system incorporating the principles of the claimed invention, but the invention is not intended to be construed in a limiting manner as a result of the preferred embodiment disclosure. 
     Referring to the figures, there is generally illustrated at  20  a vending machine for dispensing bottled and canned beverages of varied shapes, sizes, configurations and fluid volumes. The vending machine generally comprises an outer chassis or cabinet  22  and a front hinged door panel  24 , which in combination define an inner cavity  25  for housing the products to be vended, the control and refrigeration functions of the machine and other vending machine features well-known in the art. The front door panel  24  frames a transparent glass or clear plastic panel  26  which provides a clear view into the internal cavity of the cabinet and the beverage products stored in ordered manner on trays therein, when the door panel  24  is closed. The door panel  24  includes an appropriate control panel, generally indicated at  28  which includes a product selection input and monetary and credit processing system, well-known in the art. Since the control panel and its various features and functions do not form a part of this invention, they will not be detailed herein. Those skilled in the art will readily recognize many appropriate such control panels and features thereof that could be used in association with a vending machine as hereinafter described. The door panel  24  illustrated in FIG. 1 also includes a coin return slot, generally indicated at  29  and a locking handle assembly  30  that enables the door to be opened and closed in secured manner for purposes of maintenance, loading of the machine, and the like. The door panel  24  also includes a product delivery port, generally indicated at  32 , which is approximately at thigh or waist level and depicted with its door in an “open” position in FIG. 1, with a vended bottle product  40  illustrated through the open door. A more complete description of the product delivery assembly feature will be hereinafter described. 
     In the preferred embodiment, the chassis and door panel assembly is supported by a plurality of legs  34  in elevated manner above a floor or support surface to enable ease of cleaning below the machine, the ability to readily lift the machine by a pallet jack, fork lift or other moving type of structure and to provide improved ventilation for a refrigeration system (not illustrated, but well-known to those skilled in the art) for the vending machine. Since the vending machine of the preferred embodiment is configured to carry beverages, most of which require refrigeration, it is contemplated that the internal cavity (at least that portion thereof which is to contain the beverages to be dispensed) will be refrigerated by an appropriate refrigeration system. Such refrigerated portion of the machine may even be zoned for different temperatures to accommodate vendible products having different cooling needs. The upper product holding portion could also be partitioned into refrigerated and non-refrigerated compartments, into refrigerated and freezer compartments, or in other desired configurations. 
     The chassis or cabinet  22  of the vending machine is supported by an appropriate internal frame assembly generally illustrated in FIG.  4 . The frame assembly includes a plurality of front and back upright corner support standards  36   a  and  36   b  respectively connected by upper and lower front and back transverse frame members  37   a  and  37   b  respectively and intermediate front and back transverse members  38   a  and  38   b  respectively. The front and back corner upright support standards  36  and the front and back transverse frame members  37  are interconnected by a plurality of side transverse frame members  39   a  and  39   b  respectively for the left and right sides of the frame structure as viewed from the front of the machine. The frame members  36 ,  37 ,  38  and  39  collectively define a rectangular frame structure for supporting the chassis and other components of the machine. The refrigeration unit for the machine is generally located in that portion of the internal cavity defined by the framework, and positioned below the intermediate transverse frame members  38 . The product storage portion of the internal cavity defined by the framework is generally located above the intermediate transverse frame members  38 . 
     The beverage containers housed by the upper portion of the internal cavity of the vending machine  20  are supported by a plurality of beverage trays, two of which are generally indicated at  42  in FIG.  4 . While the preferred embodiment used beverage “trays”, it will be appreciated that the principles of the invention could also be applied to conventional beverage holding shelf configurations having partitions for separating the containers into ordered rows or aligned queues of beverages extending from front to back in the internal cavity. In the preferred embodiment, the beverage trays  42  are mounted to a plurality of vertically oriented tray mounting standards, one of which is illustrated at  44  in FIG.  4 . The vending machine of the preferred embodiment includes four such vertically oriented tray mounting standards  44 , as indicated in FIG.  2 . The tray mounting standard has a pair of vertically oriented and laterally spaced (from front to back) rib members  45   a  and  45   b  respectively. The rib support members  45  are integrally formed with upper and lower support brace portions  46  and  47  respectively that extend in generally horizontal manner in the direction from front to back of the machine. The upper support brace member  46  is secured to an intermediate upper transverse frame member  38  that is mounted between the front and back upper transverse frame members  37   a  and  37   b . The lower support brace member  47  is fixedly secured to the intermediate front and back transverse frame members  38   a  and  38   b  respectively. The collective support and brace member portions  45 - 48  which comprise the vertically oriented tray mounting standard  44  form in the preferred embodiment a solid fixed mounting structure for the beverage trays  42 . 
     The vertical spaced ribbed support members  45   a  and  45   b  of the tray mounting standard  44  include regularly longitudinally spaced mounting holes (generally indicated at  50 ) for mounting the beverage trays  42  to the tray mounting standard  44 . In the preferred embodiment, the mounting holes  50  are positioned along the rib support members  45  such that successive trays  42  mounted to the rib support members  45  can be positioned at relative spacings that accommodate beverage containers of varied heights. In the preferred embodiment, the trays  42  can be mounted along the spaced rib support members  45  so as to accommodate beverage containers held by the trays up to 9 inches in height. Obviously, the relative vertical spacing between the trays  42  and the number of trays mounted to the tray mounting standards  44  is a matter of design and marketing choice. In the preferred embodiment, the trays  42  are secured to the rib support members  45  through the mounting holes  50  by mounting clips  52  which enable the trays  42  to be rapidly connected and disconnected from the tray mounting standard  44  when positioning adjustment of the trays  42  is desired. Alternatively, the trays could be secured to the mounting standards by bolts on other appropriate fasteners. In the preferred embodiment, the vertical alignment of holes  50  in the foremost vertical support rib  45   a  are relatively lower than the corresponding mounting holes  50  in the rearmost vertical rib support member  45   b  such that when a support tray  42  is mounted to the spaced rib support member  45   a  and  45   b , the tray  42  will be inclined at a downwardly depending angle from back to front of the vending machine to enable beverage containers carried thereby to slide by gravity toward the open front (i.e. dispensing) end of the tray. In the preferred embodiment, the preferred angle of inclination of the tray with the horizontal is from about 8-20 degrees and most preferably about 12 degrees. The degree of inclination is a design parameter that can be varied, depending upon the type, size, weight, configuration, etc. of the container being held, the relative coefficient of friction between the container and the tray floor surface, the type of materials used to construct the tray, the temperature of the internal cavity, etc. It will also be appreciated that the principles of this invention do not require movement of the products toward the dispensing end of their respective trays or shelves to he accomplished entirely by gravity. Other biasing assist techniques well known in the art could also be employed. 
     The vertically oriented tray mounting standards  44  are configured to securely support oppositely disposed pairs of beverage trays  42  as indicated more fully in the frontal view of the tray assembly illustrated in FIG.  2 . It will be appreciated that the foregoing description with respect to the tray mounting assembly of FIG. 4 only illustrates a single tray mounting standard  44  with only several incomplete tray assemblies  42  attached thereto, for ease of description purposes. A more complete tray assembly as it might appear mounted within the vending machine is illustrated in FIG.  2 . Referring thereto, it will be noted that the completed assembly includes four tray mounting standards  44  transversely spaced from one another so as so accommodate two beverage trays therebetween, with the outermost tray mounting standards  44  being spaced from the upright corner posts  36  of the frame support structure so as to accommodate a single tray width therebetween. While the widths of the trays can vary in the preferred embodiment the product trays can accommodate beverage containers of up to 3 inches in diameter. It will be appreciated that while all of the beverage trays  42  connected to the vertical mounting standards  44  at a particular height are aligned with one another in FIG. 2, such orientation does not have to be uniform so as to define ordered horizontal rows of beverage product within the machine. In the preferred embodiment illustrated, there are five such rows or shelves of the product trays. Due to the flexible height adjustment capabilities for the trays as provided by the vertically oriented tray mounting standards  44 , each tray can be positioned along its vertical mounting standard at a different height which would accommodate the particular product size and arrangement configuration desired within the machine. 
     In the preferred embodiment, each of the trays  42  is shaped in the configuration of a U-shaped channel, generally having a lower surface or floor support surface  42   a  and a pair of oppositely disposed side walls  42   b  upwardly extending from the floor  42   a  at right angles with respect thereto. In the preferred embodiment, the side walls are spaced so as to accommodate beverage containers of up to 3 inches in diameter; however, it will be recognized that the invention is not limited by such dimension or to other non-claimed dimensions described herein. The floor  42   a  is designed to minimize sliding friction therealong. The mounting clips or bolts  52  are secured to and/or through the side walls  42   b  of the trays  42  at appropriate longitudinal locations therealong for fastening registry with the mounting holes  50  of the vertical rib support members  45 , as previously described. In the preferred embodiment each of the trays is designed to hold a collective beverage container weight of up to about 20-25 pounds. The beverage trays indicated in FIG. 4 comprise the basic tray element portion of a completed tray, and are illustrated in FIG. 4 without any beverage container release or extended side wall provisions, as will be hereinafter described in more detail. The front or dispensing end of the trays  42  which address the glass door are generally indicated by the numeral  43 . It will be appreciated that other tray or product support configurations such as, for example, wire grid trays could be used. 
     Beverage containers carried by the plurality of open-faced trays  42  are removed from the trays and transported to the product delivery port  32  a robotic beverage capture and transport assembly, generally indicated at  60  in FIG.  4 . The robotic assembly  60  operates within the vend selection space  61  (FIG. 3) which is generally that space or volume between the inner surface of the door  24  and the front surfaces of the front frame members  36   a ,  37   a  and  38   a . The robotic system will be described with reference to an X, Y, Z coordinate system in the machine. The X-direction is horizontal and parallel to the floor. The Y-direction is the vertical direction and perpendicular to the X-direction. The Z-direction is orthogonal to the XY plane and relative to the vending machine is in the direction from the front to back of the machine. 
     The robotic beverage capture and transport assembly  60  generally includes a pair of horizontally mounted rail/rack assemblies, a vertically oriented shuttle bar that rides along the horizontal rails in the X-direction, a carrier frame that moves in the Y-(vertical) direction along the shuttle bar, and a pick-up or transfer mechanism that is mounted to and moves with the carrier frame and operates in the Z-direction to remove a beverage container from a selected tray. 
     The lower rail assembly includes a mounting plate bracket  62  which is secured to and between the front upright corner support standards  36   a  and to the front intermediate transverse frame member  38   a  (FIG.  4 ). A lower stationary slide bar  63  is secured, in horizontal manner, to the mounting plate bracket  62  by a plurality of spacers  64 . A lower horizontal gear rack  65  is secured to the mounting plate bracket  62 , generally below and in spaced relationship to the stationary slide bar  63 . An optical X-position indicator plate  66  is mounted to the front corner support standards  36   a  of the frame of the vending machine. The indicator plate  66  has a plurality of markers, generally indicated at  66   a  longitudinally spaced therealong in the X-direction for providing optically detectable position markings for enabling the robotic assembly to align with the columns of trays  42  in the “X” direction. A lower moveable slide bar  67  has a pair of side slide block members  67   a  which define oppositely disposed longitudinal grooves or channels, and which are connected together by a steel mounting plate  67   b  for matingly engaging the upper and lower edges of the stationary slide bar  63 , enabling the moveable slide bar  67  to cooperatively slide along and be guided by the stationary slide bar  63 . 
     The upper horizontal rail assembly for guiding movement in the X-direction includes an elongate mounting plate bracket  68  that is secured to the upper front transverse frame member  37   a  of the frame. An upper stationary slide bar  69  is secured, in horizontal manner, to the lower elongated surface of the mounting plate bracket  68  by a plurality of spacers  70 . An elongate upper horizontal gear rack  71  is secured to a lower mounting surface of the upper mounting plate brackets  68  with its gear face addressing the front of the machine. An upper moveable slide bar  72  has a pair of side slide block members  72   a  which define oppositely disposed channels formed therein, connected together by a steel mounting plate  72   b  for matingly slideably engaging the outer edges of the upper stationary slide bar  69 . 
     In the preferred embodiment, the upper and lower moveable slide bars  72  and  67  respectively comprise a pair of opposed slotted blocks of plastic or acetyl resin material such as that sold under the Delrin® trademark suitable for providing a low-friction slideable bearing surface with the stationary slide bars. 
     The upper and lower rail assemblies carry a shuttle bar assembly for movement therealong in the X-direction. The shuttle bar assembly has an elongate upright frame member  75  with a lower mounting bracket  75   a  and an upper mounting bracket  75   b . The lower shuttle bracket  75   a  is secured to the steel plate member  67   b  of the lower moveable slide bar  67 , and the upper shuttle bracket  75   b  is secured to the steel mounting plate portion  72   b  of the upper moveable slide bar  72 . In the preferred embodiment, the upper shuttle bracket  75   b  is channel-shaped in cross-section, as illustrated best in FIG.  6 . This mounting configuration allows the upright shuttle frame member  75  to move in the X-direction as guided by the upper and lower stationary slide bars  69  and  62  respectively. 
     Movement of the shuttle frame member  75  along the upper and lower slide bars is controlled by an X-drive motor  77 , mounted in vertical manner to the lower shuttle bracket  75   a . The motor  77  is a reversible dc brush gear motor with a dynamic brake. The dynamic brake enables the motor drive gear to stop immediately when the power to the motor is discontinued, enabling accurate positioning of the shuttle assembly in the X-direction. In the preferred embodiment, the motor  77  is a 24 volt dc motor manufactured by Barber Colman, model LYME 63000-731 rated at 5.3 inch-pounds of torque at 151 rpm, whose output shaft is connected to a drive gear  77   a . The drive gear  77   a  cooperatively engages a first spur gear  78  which is connected by an elongate shaft  79  to a second spur gear  80  located adjacent the upper rail assembly. The shaft  79  connecting the spur gears  78  and  80  is journaled through appropriate bearings, one of which is shown at  81  in FIG. 6, which are appropriately mounted to and for movement with the upright shuttle bar frame member  75 . The two spur gears  78  and  80  are commonly rotated by the drive gear  77   a  of the X-drive motor  77 , and rotate about the axis of the elongate drive shaft  79 . The first spur gear  78  cooperatively engages the lower horizontal gear track  65  of the lower rail assembly and moves therealong in the direction according to rotation of the drive gear  77   a . The upper spur gear  80  cooperatively engages the upper horizontal gear track  71  of the upper rail assembly and moves therealong according to rotation of the elongate shaft  79 . Accordingly, the X-drive motor  77  controls movement of the shuttle bar frame  75  and attached components in the X-direction by spur gears  78  and  80  engaging and moving along the upper and lower gear tracks  71  and  65  respectively. Such connection ensures a fixed vertical shuttle attitude as it traverses back and forth in the vend selection space and allows for rapid movement in the X-direction without binding and without wobble or vibration that might be associated with worm gear driven configurations. 
     The position of the shuttle movement in the X-direction may be monitored and determined in any appropriate desired manner. In the preferred embodiment, an optical sensor  83  (FIGS. 7 and 8) is mounted to the shuttle frame member  75  and is positioned therealong so as to operatively align with the slots  66   a  in the optical X-position indicator plate  66 . Such mounting enables the optical sensor  83  to detect the position slots  66   a  and to thereby provide X-direction location information back to the robotic motion Controller (as hereinafter described). 
     A limit switch  84  located at the right end of the lower rail assembly and engagable by the shuttle bar assembly as it moves in the X-direction indicates the rightmost or “Home” position of the shuttle bar assembly in the X-direction. The X Home position represents a location of the robotic assembly that corresponds to a final vend position wherein a captured product is presented at the delivery port  32 , as will be described more hereinafter. 
     Movement of the robotic beverage capture and transport assembly  60  in the Y-direction is achieved by a carrier frame assembly, generally indicated at  90 , that is connected to and vertically moves along the shuttle bar frame member  75 , as described in more detail hereinafter. A vertically oriented gear rack  91  (see FIG. 3) is longitudinally mounted along one edge of the elongate shuttle bar frame member  75 . A vertical slide bar  92  (similar in nature to slide bars  63  and  69 ) is secured to one side of the vertical gear rack  91  as illustrated in FIG.  3 . The carrier frame assembly  90  is slidably and retainably mounted to and for movement along the vertical slide bar  92  by a moveable front slide block  93  mounted to the carrier frame  90  (see FIG. 2) and an oppositely disposed movable rear slide block (not illustrated), also mounted to the carrier frame  90 . The front and rear bearing blocks have oppositely disposed grooves formed therein which are cooperatively configured to slidably engage the outer edges of the vertical slide bar  92  in manner similar to that previously described with respect to the upper and lower X-rail assemblies. In the preferred embodiment, the carrier frame assembly  90  also includes an elongate bearing block secured thereto (not illustrated) through which the elongate shaft  79  passes. The bearing block includes a pair of slideable bearings for engaging the outer surface of the shaft  79  as it rotates and as the carrier frame assembly  90  moves therealong in the Y-direction. The bearings of the bearing block need to be capable of handling loads from rotation of the shaft  79  as well as from linear travel along the shaft. 
     A Y-drive motor  97  having an output drive gear of  97   a  is horizontally mounted to the carrier frame  90  near its upper end, in a manner such that its drive gear  97   a  cooperatively, matingly engages the vertical gear rack  91 . The Y-drive motor  97  is a reversible dc brush gear motor that is driven by a pulse width modulated (PWM) signal. In the preferred embodiment, motor  97  is a 24 volt dc motor manufactured by Barber Colman, model LYME 63070-X-9332. Accurate Y-axis positioning of the carrier frame  90  relative to the shuttle bar assembly and stabilization at any “at rest” position therealong is provided by the pulse width modulation signal. The motor  97  is also provided with an optical pulse encoder  100  that counts the rotations of the motor&#39;s shaft. The system Controller, translates the number of rotations information into a linear Y-direction information. This information enables the Controller to determine and control the exact vertical or Y-direction position of the carrier frame  90  relative to the product carrying trays  42  within an accuracy of from {fraction (1/32)} to {fraction (1/64)} inch. A limit switch  99  (FIG. 3) mounted to the side of the shuttle bar upright frame member  75  is positioned to provide a signal to the Controller indicating that the carrier frame assembly  90  is or is not at its “Home” position in the Y-direction. The Y Home position is a Y axis position that enables the carrier frame  90  to move with shuttle assembly  75  in the X direction into the product delivery area. 
     The carrier frame assembly  90  supports a beverage capture assembly that can assume various configurations. For example, the beverage capture assembly may be configured as a robotic arm that grasps and lifts the selected beverage container into the carriage frame assembly. However, in the preferred embodiment, the beverage capture assembly comprises a simple pivotal assembly that rotates in the Z-axis direction to release and capture a beverage container from a customer selected tray  42 . Referring to FIG. 10, the beverage capture assembly is generally indicated at  102 . The beverage capture assembly  102  is pivotally mounted to the carrier frame assembly  90  by a pivot hinge member  103  for pivotal rotation about the axis of the hinge  103 . As indicated in FIG. 10, the beverage capture assembly  102  cooperatively fits and moves into nesting position within the outer shell of the carrier frame assembly  90 . The carrier frame assembly  90  has an open bottom  90   a  and an access port  90   b  formed through its front wall. A Z-drive reversible dc brush gear motor  104  with a dynamic brake, is mounted to the bottom of the beverage capture assembly  102  and has an output drive gear  104   a . In the preferred embodiment motor  104  is a 24 volt de motor manufactured by Barber Colman, model JYHE-63200-741 rated at 3.5 inch pounds of torque at 46.6 rpm. A segment of arcuately shaped gear rack  106  is secured to one side wall of the carrier frame assembly  90  and is positioned relative to the position of the drive gear  104   a  such that the drive gear  104   a  cooperatively and matingly engages the teeth of the gear rack segment  106 . When the Z-drive gear motor  104  is energized so as to move the drive gear  104   a  in a clockwise manner (as viewed in FIG.  10 ), the lower portion of the beverage capture assembly  102  moves outward from its first position in nesting engagement with the carrier frame assembly  90  about the pivot axis of the hinge  103  (as indicated in FIG.  12 ), to a second or extended position. Reversal of the motor drive, such that the drive gear  104   a  rotates in a counterclockwise direction (as viewed in FIG. 10) causes the beverage capture assembly  102  to return to its retracted position in nesting engagement with the carrier frame assembly  90 . A pair of limit switches  230  and  229  mounted to the carrier frame assembly  90  indicate respectively when the beverage capture assembly  102  is fully extended or fully retracted (i.e. in its first or second positions). Switch  229  indicates that the beverage capture assembly  102  is fully nested within the carrier frame  90 , whereas switch  230  indicates when the beverage capture assembly  102  is in its fully extended position. The beverage capture assembly  102  includes an access port  102   a  in its front surface that cooperatively aligns with the access port  90   b  of the carrier frame assembly when the two are nested together. Both the carrier frame assembly  90  and the beverage capture assembly  102  have open back surfaces. The beverage capture assembly  102  further includes a pair of tapered beverage container guide members  107  connected to its opposed side walls and tapered in a manner so as to converge toward the front face of the beverage capture assembly for assisting in centering and supporting the outer surface of a beverage container carried by the beverage capture assembly, as will be appreciated more upon further description of the invention. The beverage capture assembly  102  further includes a floor insert member  108  having an upper friction reduced slidable surface similar in nature and material to that of the lower floor portions  42   a , and a circular detent  108   a  portion formed therein for retaining the bottom edge of a beverage container  40  captured by the beverage capture assembly. The leading edge  109  of the floor insert member  108  may have a tapered, angled, or rounded edge  109   a , as shown in FIG. 18, to minimize the likelihood of the foremost portion  110   a  of the lever guide arm  10  and the end of tray  43  from hitting against the insert member  108 . In a preferred embodiment, the floor insert member  108  includes a depressed lip  119  at leading edge  109 , on which the dispensing end of the tray  43  can rest. Floor insert member  108  may be positioned in beverage capture assembly  102  to provide a horizontal surface on which the beverage container rests during transport in the assembly  102 . Alternately, the top surface of floor insert member  108  may be angled to the horizontal. Preferably, the insert member  108  is angled toward the front of the machine so as to tip the top of the beverage container further into the beverage capture assembly  102  to ensure a secure positioning of the bottle during transport. The beverage capture assembly further includes a transmissive optical sensor, positioned just above the floor insert member. The optical sensor includes a transmitter  223  and a receiver  224  between which an optical signal passes. When the signal is broken by a beverage container received by the beverage capture assembly, a “product present” signal is sent to the system Controller. 
     The previous description of the beverage trays  42  described a simple unembellished U-shaped open end beverage delivery tray configuration. In the preferred embodiment, the delivery end portion of the tray has been modified to achieve the vending purposes of this invention. 
     Referring to FIGS. 2,  9  and  19 , it will be noted that each of the lower floor portions of the beverage trays  42  provide an extremely low-friction surface. The low friction property may be achieved by numerous different techniques and materials. In the preferred embodiment the floor insert is approximately 2 inches wide to provide support and stability to the beverage containers carried thereby, although wider and narrower floor inserts  42   a  can be used. In a preferred embodiment the insert material is any one of the acetyl resin materials sold under the Delrin® trademark, including materials known as “industrial grade” or “AF” materials, and materials impregnated or treated with additives such as silicone or fluorochemicals. Materials sold under the Celcon® trademark are also preferred. It will be appreciated that other materials capable of providing a low friction surface can also be used. For example, but not by way of limitation, filled polystyrene or glass thermoplastic composites or bubble construction principles could also be used. Additionally, materials such as polypropylene and nylon, preferably with some surface modifying coating thereon or additive therein, may also be useable. It is preferred that the hardness of the material is sufficiently high so that the weight of bottles or other food items on the floor for an extended time does not distort or deform the floor insert. 
     In a preferred embodiment, the cross-sectional configuration chosen for the insert  42   a  is a symmetrical ribbed or corrugated configuration wherein the radius of the raised rib portions  141  is in the range of about 0.035 to 0.075 inch, preferably about 0.050 inch, with the height of the rib being in the range of about 0.010 to 0.040, preferably about 0.020 inch, although other dimensions may be used. What is meant by “symmetrical” is that both the top and bottom sides of the floor insert  42   a  have ribs  141  positioned directly opposite each other, as shown in FIG.  20 . The ribs  141  on the top and bottom sides may or may not have the same geometry. In an alternate embodiment, the ribs on the bottom side may be offset from the ribs on the top side. The thickness of the insert at the land area  143  between the ribs  141  is preferably about 0.04 to 0.06 inch and the overall thickness of the insert (including the land area and the ribs) is preferably about 0.08 to 0.12 inch, more preferably about 0.10 inch. Preferably, the ribs  141  are spaced to provide a land area  143  of about 0.125 inch (⅛th of an inch), although narrower or wider spacing can be used. Eight to 10 ribs  141  across the floor insert  42   a  are preferred to provide proper stability to the bottles. However, the exact design of the floor insert (material selection, rib dimension and spacing, configuration, overall insert width, etc.) can be modified to be best suited with the beverage container being dispensed. 
     It should be noted that for simplifying the Drawing, the floor insert has not been illustrated in all of the Figures. It will be appreciated that other ratios and other low friction configurations as well as alternate configurations such as wire or rollerfloor configurations could be used. A low-friction tray floor surface is desirable to ensure that the beverage containers freely slide by gravity along the floor surface, toward the open dispensing end of the tray. This is particularly true for a tray assembly configuration wherein only the weight of the beverage container and gravity are used to slide the container toward the dispensing end of the tray. The particular surface configuration of the tray floor, in combination with the angle of inclination of the tray are design parameters that can be varied, in view of the nature of the beverage containers that are to be dispensed, in order to provide for optimal movement of the beverage containers along the tray floor surface. 
     The floor insert  42   a  can be secured in the tray  42  by various methods such as keyholes, screws, snaps, clips, detents, rivets and other mechanisms. Preferably, the attachment mechanism is integrally molded with the floor insert, for example, at the side of the floor insert. A combination of attachment mechanisms can be used. FIG. 19 shows a floor insert  42   a  with keyholes  145  which can be slid over protrusions in the tray  42 , and with side clips  147  which engage with a structure within the tray  42 . 
     Referring to FIGS. 3,  9  and  11 , it will be noted that those portions of the tray side walls  42   b  located adjacent the open dispensing end of the trays have been raised or increased in height by extension portions, generally indicated at  42   b ′. Extension portions  42   b ′ are shown as generally triangular, but may be of any configuration or dimension. The added height provides for extra stability of the beverage container at the tray&#39;s outlet end, to minimize sideways or lateral tipping of the beverage container during the dispensing operation. Extension portions  42   b ′ may be permanently attached or may be removable and replaceable as needed. 
     In some designs it may be desired to include a reinforcing device on tray  42 . For example, after repeated loading of beverage containers into the tray, the tray may become deformed or lose some of its propensity to return to its original orientation (that is, vertical walls at a 90 degree angle to the floor). A reinforcing clamp or channel may be positioned along the base of the tray  42  to provide support. This or any reinforcement may be removable and replaceable. 
     The beverage containers carried by a tray  42  are held within the tray and are either prevented or allowed to exit from the open end of the tray by a container release apparatus. In the preferred embodiment, the container release apparatus is entirely “passive” in nature (i.e. does not require any electrical or other energy powered mechanism residing on the trays, for its operation). The container release mechanism is best described with reference to FIGS. 3,  9 ,  11  and  12 . Referring thereto, the container release mechanism includes a primary pivotal lever guide arm  110  which is pivotally connected to the right side wall  42   b  of a tray (as viewed from the open front delivery end of a tray) by a first hinge pin  111 . The first hinge pin  111  and a second hinge pin  115  (later described) are secured by a bracket  112  to the outside surface of the right side wall  42   b  of the tray (as shown in FIG. 3) and have their operable mounting portions extending upwardly above the upper edge of the right side wall. The lever guide arm  110  is secured to such upwardly projecting portion of hinge  111 . The hinge pin  111  connection to the tray side wall is positioned such that the portion of the lever guide arm  110  that is located “forward” of the hinge pin  111  has a front portion thereof that extends outward, beyond the front edge of the tray floor. The foremost portion  110   a  of the lever guide arm  110  is bifurcated and bent at two angles to the general plane of the lever guide arm to form a pair of forward cam surfaces. The angled cam surfaces provide a broad “target” area for engagement and activation by movement of the beverage capture assembly  102 , as hereinafter described. The lowermost of the cam surfaces extends slightly below the floor of the tray. In a preferred embodiment shown in FIG. 21, the lowermost surface extends below the floor and includes another section  110   c  extending rearward through the hinge pin  111  (position shown in dashed lines), so as to provide a “c” shaped surface. This extension  110   c  increases the overall strength and rigidity of the guide arm  110 . The guide arm  110  may include any other designs to provide the desired structural features. The rearmost portion of the lever guide arm  110  is pivotable about the hinge  111  toward the open portion of the tray  42  with which it is associated (i.e. away from the side wall  42   b ) and retainably holds a first beverage engaging rod member  113  that is oriented generally perpendicular to the lower floor  42   a  and generally parallel to the side walls  42   b  of the tray  42 . The height of the beverage engaging rod member  113  can vary to accommodate different heights of beverage containers. The lower edge of the rod member  113  is carried by the lever guide arm  110  in spaced relation to the tray floor and floor insert members. The purpose of the beverage engaging rod member  113 , as will become clear upon a more detailed description, is to engage a beverage container in the tray and prevent its sliding movement along the tray in the direction toward its dispensing end. 
     That portion of the lever guide arm  110  located forward of the hinge pin  111  also includes a slot passageway  110   b  formed therethrough for slidably accommodating a second lever arm  114  that is pivotally mounted to the right side wall  42   b  for movement about the second hinge pin  115 . The second hinge pin  115  is mounted by the bracket  112  adjacent the forward edge of the right side wall  42   b , as indicated in FIGS. 3,  9  and  11 . The second lever arm  114  extends through the slot  110   b  to a distal end which retainably holds a second beverage engaging rod member  116  which is similar in nature to that of the first beverage engaging rod member  113 , and serves the same general purpose (i.e. to block movement of a beverage container along the floor of the tray). The slot  110   b  in the lever guide arm  110  is strategically positioned relative to the hinge pin  115  and its attached lever arm  114  such that when the lever guide arm  110  is positioned in its normal position as illustrated in FIG. 11, the “forward” edge of the slot  110   b  will engage the forward face of the second lever arm  114  to cause the second lever arm  114  to project outwardly and generally perpendicularly, laterally across the tray  42  so as to position the second beverage engaging rod member  116  held thereby directly in the path of the first-in-line beverage container, preventing the beverage container from advancing out of the open end of the tray. This situation is illustrated in FIG.  11 . In one embodiment, it may be desired to include a dimple or other type of protrusion on second lever arm  114  to increase the resistance to the advancement of the beverage container. This protrusion is preferably positioned near slot  110   b , and functions by increasing the force necessary to move lever guide arm  110  in relation to second lever arm  114 . The second beverage engaging member  116  need not be positioned in the center of the tray to accomplish its purposes. It need only engage the beverage container along its outer circumference at a position there along such that the forwardmost edge of the container does not project out beyond the front edge of the tray. The primary pivotal lever guide arm  110  is held in this “container engaging” position by a spring  118  transversely extending below the front edge of the tray, secured between the forward edge of the left side wall  42   b  or floor of a tray and a forward portion of the lever guide arm  110 . It will be noted that when the primary lever arm is positioned in it&#39;s “normal” position, the spring  118  holds the general plane of the forward portion of the lever arm  110  slightly spaced from the side wall  42   b , by the distance “d” as illustrated in FIG. 11, to prevent pivotal motion of lever  114 . When the rod member  116  is in such container engaging position (FIG.  11 ), the rearmost portion of the lever guide arm  110  and its associated first beverage engaging rod member  113  will be positioned in resting engagement against the right side wall  42   b  of the tray so as to allow passage of beverage containers along the tray lower surface and toward the open end thereof. 
     This is the “normal”, “unactivated” mode of operation of the beverage container release apparatus. The slot  110   b , lever arm  114 , engagement member, pivotal travel of the lever guide arm  110  about its hinge  111 , and tension of the spring  118  are collectively and cooperatively designed such that the forces applied to the engagement member  116  by a full tray of beverage containers as a result of their collective weight vectors in the (-Z) direction (i.e. toward the open end of the tray) will not cause the first or second lever arms  110  or  114  to pivot about their axes in a container releasing direction (counter-clockwise when viewed from above). In such position, the lever arm  114  will be prevented from rotating by the forces applied to it by engagement with the slot  110   b  of the first lever arm. 
     When an activating force, in a Z-direction toward the open face of the tray and from external thereof, is applied to the forward cam surface of the foremost portion  110   a  of the lever guide arm  110 , such cam activating force causes the lever guide arm  110  to pivot (in a counterclockwise direction as viewed from above) about its hinge pin  111  against the bias of spring  118 . Such pivotal action causes the rearward portion of the primary lever arm to rotate in counterclockwise direction about hinge  111 , moving the first beverage engaging rod member  113  into the advancing path of a second-in-line advancing beverage container, and forces the forward portion of the lever guide arm to pivot  110  into resting engagement with the right side wall  42   b  of the tray. As the lever guide arm  110  rotates about the hinge pin  111 , the forward portion of the lever guide arm will “slide” to the right as viewed from the front of the machine, against the second lever arm  114  by reason of the slot  110   b , until the lever guide arm  110  is in resting engagement against the right side wall  42   b . As such sliding motion occurs, the lever guide arm  110 , through its slot  110   b , will no longer retard pivotal movement of the second lever arm, and the second lever arm  114  will pivot, as a result of forces applied to it by the first-in-line beverage container engaging its beverage engaging rod member  116 , in a counterclockwise direction as viewed from above, about the second hinge pin  115 , until the second lever arm  114  rests generally parallel to and alongside the lever guide arm  110 . At that position the second beverage engaging rod member  116  will lie in resting engagement against the forward portion of the lever guide arm  110 , allowing the first-in-line beverage container to freely slide by gravity out of the open end of the tray  42 . At the same time, the first beverage engaging rod member prevents sliding motion of the second-in-line container and all containers behind it, from sliding down the tray. This process is further described in more detail hereinafter in relation to a “vend cycle” and FIGS. 12 and 13. 
     When the “activating” pressure against the forward cam surface of the foremost portion  110   a  of the lever guide arm  110  is released, bias of the spring  118  against the forward portion  110   a  of the guide arm  110  will cause the lever guide arm  110  to return to its normal position by pivoting in a clockwise direction (as viewed from above) around its hinge pin  111 . Such pivotal action will cause the wall of the slot  110   b  in the lever guide arm  110  to apply pressure against the second lever arm  114 , rotating the second lever arm  114  about its pivot hinge  115 , which in turn will move the second beverage engaging rod member  116  back to its “blocking” position near the front of the tray. During this “return” procedure, there are no forces from beverage containers being applied to the lever arm  114 , since the first beverage engaging rod member  113  is holding back the beverage containers remaining in the tray. However, as the rod member  116  is returning to its blocking position, the rod member  113  is simultaneously returning to its normal position alongside the side wall  42   b . The “return to normal” cycle time is fast enough so as to allow the lever  114  and its associated rod  116  to return to their normal positions before the beverage containers released by the rear rod  113  slide into advancing engagement with the rod  116 . 
     Referring to FIG. 1, the product delivery port  32  has associated therewith an automated delivery door opening and closing assembly, illustrated in FIGS.  14  and  15 . As indicated above the product delivery port is preferably located between thigh and waist level so that the customer does not have to unduly bend to retrieve the vended product therefrom. In a preferred configuration, the height of the delivery port is at least 27 inches from the floor and more preferably at a height of 30 inches or more. FIG. 14 illustrates the door opening assembly  120  as it would be viewed from the front right side of the vending machine, and FIG. 15 illustrates the door opening assembly as it would appear from its right back position. The door opening assembly  120  generally has a front mounting plate  121  defining an access port  121   a  therethrough which cooperatively aligns with the product delivery port  32  formed in the front panel of the vending machine door  24 . The door opening assembly  120  also has top and right side wall portions  122   a  and  122   b  respectively, but does not have a left side panel. The open left side enables the moveable carrier frame assembly  90  and its mating beverage capture assembly  102  to move into cooperative docking alignment with the door opening assembly  120  such that the access port  121   a  of the door opening assembly operatively aligns with the access port  90   b  of the carrier frame assembly  90  and the access port  102   a  as the beverage capture assembly  102  at the end of a vending cycle. This position also correspond to the X Home and Y Home positions. A reversible electric motor  123  having an output drive gear  123   a  is mounted to the right side panel  122   b  of the door opening assembly. The door opening assembly  120  further includes a slidable door panel  125  that is mounted for sliding movement in the vertical direction. The left side (as viewed from the front) of the door panel  125  slides within a channel  126 . The right side of the door panel  125  is integrally connected with a gear track extension  127  that rides within a retaining channel (generally indicated at  128 ) of the door opening assembly. The output drive gear  123   a  of the electric motor  123  is positioned to engage the gears of the gear track extension  127  through an opening  128   a  in the right side channel  128 . As the electric motor  123  is energized, the output drive gear  123   a  rotates to move the engaged rear track extension so as to raise and lower the slidable door panel  125 . The door panel is illustrated in its lowered position in FIGS. 14 and 15. A pair of limit switches  130  and  131  are mounted to the right side wall  122   b  of the door opening assembly  120  for respectively detecting the raised (closed) and lowered (open) positions of the door panel  125 . The gear driven door configuration provides a secure door opening mechanism that is not easily pried open by vandals or thieves when in a closed position. The product delivery port also has associated therewith a security lock system for locking the carriage frame assembly  90  in its docked position at the product delivery port at the end of a vend cycle. Such locking prevents unauthorized or vandalous entry into the interior of the vending machine through the product delivery port when the delivery door is open. The security locking apparatus generally includes a motorized lock, indicated generally at  218  in FIG. 1, a sensor  216  for detecting a locked status and a sensor  217  for detecting an unlocked status. Those skilled in the art will appreciate that such locking apparatus can assume many mechanical configurations, the details of any one of which are not limiting to the scope of this invention. Further, while a particular configuration of a vertically movable door has been described, those skilled in the art will appreciate that other configurations, as for example, rotatable door panels can also be used. 
     FIGS. 16A and 16B generally illustrate the various electronic and control functions and components of the vending machine and their functional relationship and interaction to one another. FIG. 16 is not intended to be exhaustive of all functional and electronic details of the machine, but is a general overview of the major functions. The primary functions of such machines are well-known in the art and will not be detailed herein, since they do not form a part of the invention. It is well within the province of one skilled in the art to configure a vending machine in the proper format configuration and under proper control for which it is intended to serve. Accordingly, it is not believed necessary to further belabor such generalities in this application. In general, a Controller  200  provides all centralized control functions for the vending machine. A Controller could be in the nature of a computer or a microcontroller with embedded code, having a central processing unit through which all functions in the machine can be programmed controlled and coordinated. Such a central processing unit would include such things as a main program stored in memory that operates in connection with a plurality of other files such as utility files, screen picture files, screen voice files, product data files, sales report files, documentation files, robotic path files, and the like-generally-known to those skilled in the art. In a typical machine, the Controller  200  is coupled to a power supply  201  upon which it depends for its own energization, and may control the application of power from the power supply to other functions throughout the system. In this regard, it should be noted that while various electrical components have been disclosed in describing the preferred embodiment, no power connections have been illustrated as associated with those components, it being understood that appropriate power connections are provided in the operative machine. The power supply  201  is also connected to provide various lighting functions ( 202 ) required in the machine. The Controller  200  is also connected to operator input means, generally designated as a keyboard  203 , which can represent both a service keyboard for programming and entering information into the Controller as well as the product selection keys or pads located on the front of the machine. Controller  200  also operates various other customer interface features such as a display panel  204 , possibly a speaker  205 , and appropriate credit interface networks, generally represented at  206 . The credit interface function  206  communicates with such peripheral systems as bill validators  207  a coin mechanism  208  and a debit card network  209 . Controller  200  also controls the refrigeration functions  210  which include communication with and control of such ancillary functions as temperature sensors  211  and the compressor  212  and fan  213  which are typically operated through a compressor relay  214 . 
     The Controller  200  controls the security lockout functions previously described for locking the carriage frame assembly  90  at the product delivery port following a vend cycle, generally indicated at  215 . The security lockout function includes communication with the locked sensor  216 , the unlocked sensor  217  and the locking motor  218 . 
     The Controller  200  also communicates with and controls the functions associated with the operation of the delivery door (functional block  220 ) and the various functions of the robotic beverage capture and transporting functions. The delivery door function, includes communication with the door open and door closed limit switches  131  and  130  respectively and the door control motor  123 . The product present sensor function of the transmissive optical sensor  222  mounted in the beverage capture assembly  102  communicates with the Controller  200 . The transmitted and receiver portions of the product sensor are indicated at  223  and  224  in FIG.  16 A. The X, Y and Z-direction control functions, generally indicated at  225 ,  226  and  227  respectively are coordinated through a delivery head control network  228  which communicates with Controller  200 . The X-direction control function communicates with the X-Home switch  84 , the X-drive motor and brake  77  and the X-position optical sensor  83 . The Y-direction control function  226  involves communication with the Y-motor optical encoder  100 , the Y-Home switch  99  and the Y-drive motor  97 . The Z-direction control function  227  communicates with the Z-in and Z-out switches  229  and  230  respectively mounted on the carrier frame assembly  90  for detecting pivotal motion of the beverage capture assembly  102  and the Z-drive motor and brake  104 . 
     In operation, the plurality of trays  42  within the vending machine are adjusted relative to their associated support tray mounting standards  44  to accommodate the relative heights of the products desired to be vended. The trays are then loaded with the desired beverage containers through the open door  24 . The loaded beverage containers are retained in ordered manner on their respective trays by the container release mechanisms previously discussed, at the forward ends of the trays. In general, the machine has two modes of operation, a “Service” mode which is entered whenever the door  24  is open and will not be discussed herein. The normal mode of operation is the “Operate” mode and is the one which is of general concern to this invention. Upon entering the “Operate” mode a diagnostic check is performed on the vending mechanism. If the diagnostic check fails, the Controller  200  takes the unit out of service and displays an appropriate “Out-of-Service” message on its display panel  204 . 
     After a power-up or reset condition, the Controller goes through a startup sequence which energizes the various functional peripherals of the system. In an idle state, the external display of the machine will show the accumulated credit amount when no keypad or vend activity is present. If there is still a beverage container or product in the delivery bin of the machine an appropriate message such as “PLEASE REMOVE PRODUCT” will be flashed continuously until the product is removed. Keypad depressions and credit accumulation is disabled if a product is still in the delivery bin. The carriage frame assembly  90  will be locked in its docked position at the product delivery position. The credit accumulation, credit acceptance and the handling of cash, bills and tokens is similar to that of other vending machines and is well-known in the art. 
     The process of initializing a “Vend Process” is illustrated in the flowchart of FIGS. 17A and 17B. Referring thereto, following the start-up sequence  300 , generally described above, the Controller continually looks to see if a keypad entry or selection has been made ( 301 ). When a selection is entered on the keypad, the Controller will determine ( 302 ) whether sufficient credit is available for the given selection. If the accumulated credit is greater than or equal to the selection price, a vend attempt will be made for that selection. During this time, the customer&#39;s selection will also be shown on the display panel. If the credit accumulated is less than the selection price, the price will be flashed for three seconds or until a new selection key is pressed. Also, if the level of the coin changer assembly&#39;s least value coin tube is below its lowest sensor, the “Use Correct Change” sign will be continuously illuminated. 
     Assuming that proper credit has been accumulated for the selected product, the Controller will ensure that the beverage capture assembly  102  is empty ( 303 ). If the beverage capture assembly  102  still contains a beverage container, the Controller will not allow the vend cycle to continue until the beverage container has been removed from the capture mechanism. The Controller then checks to see if the delivery door  125  is positioned in a closed position (decision block  304 ). If the door is open, the Controller will not allow the vend cycle to proceed. 
     If both the conditions of an empty beverage capture assembly and a closed delivery door are satisfied, the vend cycle proceeds and the security lock motor  218  is energized to unlock the carriage frame assembly  90  for movement ( 305 ). Once unlocked, the shuttle bar assembly  75  is enabled for movement in the X-direction, and Pulse Width Modulated (PWM) signals are sent to the Y-drive motor  97  to move the carrier frame assembly  90  slightly up, in the Y-direction, to a “hovering” position just above the Home seated area so that the Y-home switch  99  is activated ( 306 ). This allows the carriage frame assembly  90  to clear the product delivery area when it begins moving with the shuttle assembly  75  in the X-direction. The carrier frame assembly  90  is held at its hovering Y-position ( 307 ) and the shuttle bar assembly is moved in the left X-direction to its first position as detected by the optical column position sensor  83  and the associated optical position indicator plate  66  ( 308 ). In the preferred embodiment the “first” X-position is the position in alignment with the right most column of trays in the vending machine, just left of the control panel as viewed in FIG.  1 . 
     The controller then energized both the X and Y drive motors  77  and  97  so as to position the carriage frame assembly  90  in operative position in front of the customer selected tray  42 . The particular tray column position (in the X-direction) is sensed by the optical sensor  83  and its associated position indicator plate  66 . The desired amount of travel in the Y-direction is determined by the optical encoder  100  associated with the Y-drive motor  97 , which counts the revolutions of output shaft movement when the Y-drive motor is running. These functions are indicated by block  309  in FIG.  17 B. When the carrier frame assembly  90  reaches the desired Y-direction position, its movement is stabilized by the PWM drive signal ( 310 ), which maintains the carriage frame assembly at the desired Y-direction height. As described above, the PWM Y-motor control feature can enable accurate positioning of the carriage frame assembly relative to the selected tray within {fraction (1/32)} to {fraction (1/64)} of an inch. 
     When the carriage frame assembly  90  is properly positioned before the customer selected tray, the Z-drive motor  104  is energized to rotate the beverage capture assembly  102  relative to the carrier frame assembly  90  until the limit switch  230  indicates full rotated extension of the beverage capture assembly  102  ( 311 ). As the beverage capture assembly arcuately moves toward the selected tray  42 , the forward edge thereof engages the forward cam surface  110   a  of the foremost portion of the lever guide arm  110  on the selected shelf. As the beverage capture assembly continues to rotate in the forward direction, the lever guide arm  110  is rotated thereby about its hinge pin  111 , causing the second lever arm  114  to rotate in a counterclockwise direction (as viewed from above), moving the beverage engaging rod member  116  out of engagement with the foremost (first-in-line) beverage container on the selected tray. Simultaneously, the rearmost beverage engaging rod member  113  is moved into blocking position in front of the second-in-line beverage container, preventing the second-in-line beverage container from progressing down the inclined selected tray. Once the rod member  116  is removed from retaining contact with the first-in-line beverage container, the first-in-line beverage container is permitted to slide by gravity out of the open end of the selected tray and into the rotated beverage capture assembly  102  which is now in direct alignment with the selected beverage tray. It should be noted that when the beverage capture assembly  102  is fully rotated by the Z-drive motor  104 , as indicated by activation of the Z-out switch  230 , the upper surface of the floor insert member  108  of the beverage capture assembly  102  will be co-planarly aligned with the upper surface of the lower floor insert  42   a  of the selected beverage tray  42  so as to form a continuous sliding surface for the first-in-line beverage container to slide from the open end of the selected tray and into the aligned beverage capture assembly  102  (see FIG.  12 ). As the first-in-line beverage container slides into the beverage capture assembly, its lower surface will enter the circular detent portion  108   a  of the floor insert member, further retaining the container in fixed placed within the beverage capture assembly. The upper portion of the captured container will engage the tapered beverage container guides  107  to add further balancing support to the captured container within the beverage capture assembly. At this position, the captured beverage container will also activate the product present sensor  222  within the beverage capture assembly, indicating that the selected first-in-line beverage container actually has been dispensed from the selected tray and has been captured by the beverage capture assembly  102 . As long as the beverage capture assembly  102  remains in its Z-out receiving position, its engagement with the primary pivotal lever guide arm  110  will maintain the guide arm at its activated/rotated position against the bias of the spring  118 , maintaining the second beverage engaging rod member  116  in front of the second-in-line beverage container, to prevent its movement along the lower surface of the selected tray. 
     Referring back to FIG. 17B, after the Z-out switch  230  has been activated ( 311 ), the Controller will wait for one second for the selected first in-line container to slide into the beverage capture assembly ( 312 ). The Controller then interrogates the product present sensor  222  to see if the beverage capture assembly  102  has actually received the selected beverage container (decision block  313 ). If the beverage capture assembly  102  is empty, the Controller repeats this process for up to three times. If the beverage capture assembly  102  remains empty after three cycles through its box  313  check, the Controller assumes that the selected tray is empty and flashes a “Sold Out” signal on the vending machine display. If this condition occurs, the Z-motor is energized to return the beverage capture assembly into the carriage frame assembly, the X and Y motors are energized to return the carriage frame assembly to its Home position, and the customer&#39;s money is refunded, ending the Vend cycle. 
     If the product present sensor  222  indicates that a beverage container has in fact been received by the beverage capture assembly  102 , the Controller will activate the Z-drive motor in reverse direction to pivotally retract the beverage capture assembly  102  back into the carrier frame assembly  90  until the Z-in switch  229  indicates that the beverage capture assembly  102  is fully returned in nesting position within the carrier frame assembly  90  ( 314 ). As the beverage capture assembly  102  is withdrawn back into the carrier frame assembly  90 , its forward edge will release pressure against the forward cam surface of the foremost portion  110 a of the primary lever guide arm  110 , enabling the lever guide arm  110  to be retracted to its normal position under influence of the spring  118 . As the lever guide arm  110  rotates back to its initial position, the second lever arm  114  will once again restore the beverage engaging rod member  116  to its blocking position across the open end of the selected tray, while motion of the rearward portion of the lever guide arm  110  will withdraw the beverage engaging rod member  113  from its engagement with the previously second-in-line beverage container. As the rod member  113  releases its contact with the beverage container the second-in-line beverage container will slide under the force of gravity along the tray floor until it comes into resting engagement with the rod member  116 . In this position, the previously second-in-line container now becomes the first-in-line container in that selected product tray. Simultaneously, all of the other qued beverage containers carried by that tray will also simultaneously move “forward” in the tray, each advancing one position, toward the dispensing end of the tray. This process is schematically indicated in FIG. 13 for a full vend cycle from the tray. The entire process of having transferred the selected beverage container from the selected tray and into the beverage capture assembly  102  is achieved in smooth continuous manner without dropping the beverage container or imparting any jarring blows or forces to the container. 
     Once the Z-motor has stabilized following activation of the Z-in switch  229 , the X and Y drive motors  77  and  97  respectively are simultaneously energized to move the shuttle bar  75  and the carrier frame assembly  90  back to the “first” X-position, carrying the captured selected beverage container to that position ( 315 ). The floor detent  108   a  and the tapered beverage container guides  107  of the beverage capture assembly  102  help support and hold the captured beverage container within the beverage capture assembly during the transport phase. Once the carrier frame assembly  90  reaches the first position, the X-drive motor  77  is activated to move the shuttle bar so as to move the carrier frame assembly  90  to the X “home” position at which point the carrier frame assembly will cooperatively nest within the door opening assembly  120  such that the access ports  121   a ,  102   a  and  90   b  are all in operative alignment ( 316 ). 
     At the X “home” position, both the X and the Y drive motors are deenergized and the carrier frame assembly  90  is locked in position by the locking motor  218  at the delivery station ( 317 ). With the lock set, the Controller energizes the delivery door motor  123  until the door open switch  131  indicates that the delivery door is in a fully open position ( 318 ). The Controller then interrogates the product present sensor  222  in the beverage capture assembly  102  (decision block  319 ) to determine when the captured beverage container is removed from the beverage capture assembly  102 . When the delivery door opens, the customer making the beverage selection simply needs to reach into the delivery access port  32  and lift the delivered beverage container forward and up out of the beverage capture assembly. Since the delivery access port  32  is located at a higher (approximately waist) level then most vending machine delivery vends, the customer does not have to unduly bend or contort his/her body in order to remove the selected beverage from the machine. 
     When the delivered beverage container has been removed from the delivery port, the product present sensor  222  will inform the Controller of that fact, and after a two-second delay ( 320 ) the Controller will energize the delivery door motor  123  so as to close the delivery door ( 321 ). Once the delivery door is closed, as indicated by activation of the door closed switch  130 , the vend cycle is complete ( 322 ). Following a successful vend, vend housekeeping matters such as incrementing of the electronic cash counter and the vend counter, etc. will be performed as is well-known in the art. 
     It will be appreciated that the above process provides a smooth continuous vending sequence, all in view of the customer, to deliver the selected beverage container to the customer without jarring, dropping, or rolling of the container, or otherwise subjecting the container to sharp or severe impact forces. Upon removal of the container from the delivery port, the consumer can immediately open the container without concern for its contents exploding, or foaming out of the container, and without concern for damage being caused to fragile containers during the vending process. It will also be appreciated that since the delivery port is located in the side control panel, that area near the bottom of the machine that with prior art devices was used for delivery bins, can be used to advantage to store more product within the machine. It will also be appreciated that the apparatus and process allows for greater flexibility in arranging products of varied sizes, shapes, volumes and types of containers within the same machine and that the delivery door position is accommodating to the consumer. It will also be appreciated that implementation of the principles of the invention can be achieved in an economical manner since none of the product trays or shelves require any active and expensive components in order to effect a vend. These and other features and advantages of the invention will be readily apparent to those skilled in the art in view of the foregoing description. 
     It will be appreciated that while a preferred embodiment description and application of the invention have been disclosed other modifications of the invention not specifically disclosed or referred to herein will be apparent to those skilled in the art in light of the foregoing description. This description is intended to provide concrete examples of a preferred embodiment structure and application clearly disclosing the present invention and its operative principles. Accordingly, the invention is not limit to any particular embodiment or configuration or component parts thereof. All alternatives, modifications and variations of the present invention which fall within the spirit and broad scope of the appended claims are covered.