Abstract:
An apparatus for dispensing a beverage, for use with pressurized sources of one or more fluids, includes a handle having one or more valve chambers; a fluid valve in each valve chamber; one or more butterfly plates, each configured to bias one or more of the valve stems of the valves towards a valve-open position when the butterfly plate is pressed, thus opening fluidic communication from each of the fluid sources to a corresponding discharge opening; and a ball bearing cluster which provides one or more pivot points for the butterfly plates. The ball bearing cluster includes a retainer and at least one ball-shaped projection projecting from the retainer. The ball-shaped projection remains in a substantially fixed position and orientation with respect to both the retainer and the handle when one or more of the butterfly plates is pressed. The ball bearing cluster and butterfly plate may be molded.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Patent Application No. 60/989,611, filed Nov. 21, 2007, the teachings of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a beverage dispensing apparatus of the type in which several different beverages are dispensed from a single beverage dispensing head by pressing an appropriate button. In particular, the present invention is related to improvements in the deployment of the butterfly plates in such a beverage dispensing apparatus. 
     Hand-held beverage dispensers which provide an operator with the ability to dispense a number of different beverages by merely pressing an appropriate button are known. Sometimes these hand-held dispensers are referred to as bar guns. One such bar gun system is described in the assignee&#39;s issued U.S. Pat. No. 4,986,449, entitled: “Beverage Dispensing Apparatus,” the disclosure of which is hereby incorporated by reference. A feature of the apparatus of the &#39;449 patent involves the use of butterfly plates to selectively actuate one or more valves for the dispensing of one or more base fluids or mixing fluids. As disclosed in the &#39;449 patent, to maintain the butterfly plates in place on the abutment portion of the bar gun handle while allowing the plates to pivot, each butterfly plate includes a plurality of ball bearing projections which fit within corresponding cavities in the abutment. The ball bearing pivot points for the butterfly plates are quite small, thereby reducing friction and increasing leverage for an easier activation. 
     While the above-described beverage dispensing apparatus has proven to be extremely reliable and successful in operation, it is a rather complex device. For example, in the apparatus of the &#39;449 patent the butterfly plates require the time-consuming and tedious welding of metal (e.g., steel) balls into complementarily-shaped recesses formed in the butterfly plates. In operation, when the assembled butterfly plate is pushed down to activate one or more valves, the ball joint turns on the acrylic bar gun handle imposing wear in the bar gun handle sockets that receive the ball. This can cause premature wear on the acrylic ball sockets. Moreover, sometimes the welding of the balls to the plates can leave burrs or flaws on the surface of the metal balls, either rendering the assembled plates useless, or creating further premature wear on the bar gun handle sockets that receive the balls. 
     There is therefore a need to manufacture such a bar gun that does not suffer from the above shortcomings. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention improves upon the butterfly plates assembly of a bar gun, eliminates the welding of the balls to the butterfly plates and the need to purchase such precise and intricately small balls by using molded ball bearing clusters that are shaped and dimensioned to fit in recesses in the butterfly plates, thus providing the pivot points for the butterfly plates. The ball bearing clusters are preferably made by molding bearing quality acetal plastic materials. The bearing material is less costly than the previously used metal balls and the ball bearing cluster will thus be the least costly wear item in the bar gun. 
     In one embodiment, an apparatus for dispensing a beverage of the type for use with pressurized sources of base and mixing fluids has a handle having a base fluid valve chamber and a mixing fluid valve chamber, each valve chamber having an entry cavity and an exit cavity, the entry cavity being positioned on one side of a valve chamber seat, and the exit cavities being positioned on the other side of the valve chamber seat; a base fluid valve stem disposed in the base fluid valve chamber and a mixing fluid valve stem disposed in the mixing fluid valve chamber, said base fluid valve stem and said mixing fluid valve stem each having a valve stem seat for a sealable engagement with a valve chamber seat in a valve closed position; an O-ring disposed around the valve stem to prevent fluid leaks between the valve stem and the valve chamber; a butterfly plate disposed over the base and mixing fluid valve stems, said butterfly plate being configured to bias the valve stems toward a valve open position upon a tactile input from an operator; means for biasing the base and mixing fluid valve stems toward the valve closed positions; a ball cluster bearing sized and dimensioned to pivotably couple the butterfly plate with an interior surface of the handle upon which the ball cluster bearing rests; and means for fluidly coupling the base and mixing fluid exit cavities to a discharge opening. 
     For a further understanding of the nature and advantages of the invention, reference should be made to the following description taken in conjunction with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the embodiments of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a cross-sectional view of a prior art bar gun type beverage dispenser. 
         FIG. 2  is an exemplary cross-sectional view of a bar gun type beverage dispenser with butterfly plates and cluster bearings in accordance with one embodiment of the present invention. 
         FIG. 2A  is an exemplary cross-sectional view of a bar gun type beverage dispenser with butterfly plates, cluster bearings, and O-ring retainer in accordance with one embodiment of the present invention. 
         FIG. 3  is an exemplary drawing of the cluster bearing of  FIG. 2 . 
         FIGS. 4A-B  are exemplary drawings illustrating a six-balls and an eight-balls configurations of ball clusters in accordance with the embodiments of the present invention. 
         FIGS. 5 and 5A  show exploded views of molded bar guns that can be used with the embodiments of the present invention. 
         FIG. 6  illustrates an O-ring retainer constructed in accordance with one embodiment of the present invention. 
         FIG. 7  illustrates an exemplary injection molding configuration for the making of the cluster bearings in accordance with one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention improves an assembly of the butterfly plates of a bar gun, eliminates the welding of the balls to the butterfly plates and the need to purchase such precise and intricately small balls by using molded ball bearing clusters that are shaped and dimensioned to fit in recesses in the butterfly plates. The molded ball bearing cluster is preferably made from bearing quality acetal plastic materials. The bearing material is less costly than the metal balls of the existing bar guns. Therefore, the ball bearing cluster will be the least costly wear item in the bar gun. Acetal plastic&#39;s benefits include a low coefficient of friction, high strength, low moisture absorption and easy machinability. It is a desirable material for applications with close-tolerance mechanical parts, such as FDA applications as well as for food service applications. Acetal plastics retain their toughness through a broad temperature range and are a good choice in wet environments. 
       FIG. 1  illustrates a cross-sectional view of a prior art bar gun type beverage dispenser  100 . As shown in  FIG. 1 , to maintain ball bearing  140  in place on abutment portion  120  of bar gun handle  130  while allowing the butterfly plates to pivot, each butterfly plate  110  is attached, e.g. brazed or welded, with ball bearing  140 . When butterfly plate  110  is depressed or released, ball bearing  140  pivots in abutment portion  120  of bar gun handle  130 . Thus, a wear surface exists where ball bearing  140  and abutment portion  120  mate. The ball bearing pivot points are quite small, thereby reducing friction between ball bearing  140  and abutment  120 , and also increasing the butterfly plate leverage for an easier activation. However, since stainless steel ball bearing  140  is much harder than the mating plastic abutment portion  120  on bar gun handle  130 , ultimately it will be the more expensive part, i.e. bar gun handle  130 , that wears out and must be replaced. 
       FIG. 1  also shows valves  150  that are used to control the flow of base fluids or mixing fluids. O-ring  160  can be disposed around valve  150  to prevent base or mixing fluids leaking around the valve and further toward butterfly plate  110 . However, O-ring  150  is disposed on the inside of handle  130 . Therefore, either valve  150  should be removed first for the access to a defective O-ring or a special purpose tool should be had to remove a defective O-ring, both options being expensive and time consuming. 
       FIG. 2  is a cross-sectional view of a bar gun beverage dispenser  200  with butterfly plates  210  and ball bearing cluster  240  in accordance with one embodiment of the present invention. As shown in  FIG. 2 , ball bearing cluster  240  can be used to operationally couple butterfly plates  210  with socket  220  on the interior surface of handle  230 . Valve  265  is disposed in each valve chamber  270 . When an operator depresses butterfly plate  210 , valve stem  250  is pushed away from valve chamber seat  271  and into valve chamber  270 , thus breaking the contact between valve stem seat  260  on valve stem  250  and valve chamber seat  271  on valve chamber  270 , and opening a flow path for the base or the mixing fluid. Entry and exit chambers are fluidically connected with chamber  270 , such that the entry chamber is configured on one side of valve chamber seat  271 , and the exit chambers is configured on the other side of valve chamber seat  271 . 
     Butterfly plate  210  has recess  211  which is configured and dimensioned to pivotably mate with a ball-shaped projection on ball bearing cluster  240 . When depressed, butterfly plate  210  can pivot about the ball-shaped projection, while ball bearing cluster  240  stays in a substantially fixed position with respect to socket  220  of handle  230 . Since there is no movement of ball bearing cluster  240  against socket  220  there is very little wear over the interior surface of handle  230 . Therefore, the use of ball bearing cluster  240  is an improvement over the prior art design where precision stainless steel ball bearing  140  must be welded or brazed to the recess in butterfly plate  110 , and where a wear-out surface is created between the stainless steel ball bearing  140  and abutment portion  120 . Butterfly plates  210  can be held in place by retainer plate  280 , which further assures that ball bearing cluster  240  stays in contact with socket  220  and butterfly plate  210 . 
       FIG. 2A  is a cross-sectional view of a bar gun beverage dispenser  200 A with O-ring retainer  256  in accordance with one embodiment of the present invention. O-ring  255  prevents beverage leaks around valve stem  250  and further toward butterfly plate  210 . O-ring  255  can be disposed around valve stem  250  outside of valve chamber  270 . O-rings  255  can be held in place by O-ring retainer  256 . Therefore, in order to gain access to O-ring  255 , O-ring retainer  256  has to be removed, but valve stem  250  may stay in valve chamber  270 , and the O-ring replacement can be accomplished without special tooling. Furthermore, O-ring retainer  256  provides an additional alignment surface for valve stem  250 , thus reducing the wear out of handle  230  caused by miss-alignment of valve stem  250 . 
       FIG. 3  is an exemplary drawing showing a plan view and a side view of ball bearing cluster  240  of  FIG. 2 . As shown in  FIG. 3 , ball bearing cluster  240  has a plurality of ball-shaped projections  242 , which are held at required locations by retaining sheet  241 . A plate-like retaining sheet having uniform thickness is illustrated, but other retaining sheets are also possible, for instance a retaining sheet having non-uniform thickness or a retaining sheet having empty spaces. Ball bearing cluster  240  can also include aperture  244  for receiving a retaining fastener (not shown) which can hold retainer plate  280  against bar gun handle  230 . Many different sizes of ball-shaped projections  242  are possible. One typical size is 0.094 inches in diameter. Ball bearing cluster  240  can be made from bearing quality acetal plastic material or other suitable material. 
     Different configurations of ball bearing cluster  240  can be used with different bar gun configurations, for example bar guns for 8, 10, 12 or 14 beverages. For example, a 10 beverage gun allows for the dispensing of 8 flavored mixed beverages, a plain water, and a plain soda dispensing. Likewise, a 12 beverage gun allows for the dispensing of 10 flavored mixed beverages, a plain water, and a plain soda, whereas a 14 beverage gun allows for the dispensing of 12 flavored mixed beverages, a plain water, and a plain soda.  FIGS. 4A-B  illustrate two exemplary configurations of ball bearing cluster  240  in accordance with the embodiments of the present invention.  FIG. 4A  shows ball bearing cluster  240 A having 6 ball-shaped projections  242  and aperture  244 .  FIG. 4B  shows ball bearing cluster  240 B having 8 ball-shaped projections  242  and aperture  244 . Multiple ball bearing clusters can be combined within one bar gun to achieve a desired configuration for beverage dispensing. 
       FIG. 5  shows an exploded view of a molded bar gun that can be used with the embodiments of the present invention. Bar gun  200  includes valve chambers  270  for receiving valve stems  250  and sockets  220  for receiving ball shaped projections  242 . One or more ball bearing clusters  240  may mate against sockets  220  on handle  230 . For example, two of the ball clusters shown in  FIG. 4B  may be used with handle  230  shown in  FIG. 5 , depending on the required configuration and number of the beverages to be dispensed. Other combinations are possible.  FIG. 5  also illustrates that butterfly plates  210  can pivot around ball-shaped projections  242  when depressed against valve stems  250 . Butterfly plates  210  may come in different sizes, thus covering different number of valve stems  250 . Retainer plate  280  can be secured by retainer plate fastener  281  with handle  230  to keep ball bearing cluster  240  in contact with sockets  220  on the handle and with recesses  211  (shown in  FIG. 2 ) on butterfly plates  210 . Beverage button plate  344  can be secured with handle  230 . Beverage button plate  344  can also house beverage buttons  290 . 
       FIG. 5A  shows an exploded view of a molded bar gun that can be used with the embodiments of the present invention. Modified bar gun  200 A includes O-ring retainer  256  which keeps O-rings  255  around valve stems  250  to prevent or minimize beverage leaks toward butterfly plates  210 . Valve chambers  270  are sized to receive O-rings  255 . The pressure from O-ring retainer  256  may deform O-rings  255 , thus further improving sealing around valve stems  250 . A single O-ring retainer  256  per bar gun is shown, but the embodiments with multiple O-ring retainers per bar gun are also possible. 
       FIG. 6  shows several views of O-ring retainer  256  constructed in accordance with one embodiment of the present invention. O-ring retainer apertures  258  can receive retainer plate fasteners  281  (shown in  FIG. 5 ) that secure butterfly plate  210  against handle  230 . A centrally located clip  259  can connect O-ring retainer  256  with handle  230 . When O-ring retainer  256  connects with handle  230 , a plurality of O-ring holding feet  261  disposed on one side of O-ring retainer  256  press against the O-rings. Consequently, the O-rings, which are disposed around valve stems  250  (see, e.g.  FIG. 2A ), deform and seal the opening around valve stems  250 , thus preventing fluid leaks.  FIG. 6  illustrates that ribs  257  may be used to provide for structural enforcement for O-ring retainer  256 . O-ring retainer  256  can be molded from a bearing grade acetal plastic material, or other suitable materials known to those skilled in the art. The inventive O-ring retainer provides a significant improvement to the bar gun design in terms of serviceability, because it allows an easy access to O-rings  255  by simply lifting the O-ring retainer, instead of having to disassemble the gun as is presently done. O-ring retainer  256  also provides additional alignment for the valve stems. With the combination of the ball clusters and the O-ring retainer, the assembly of the bar gun is significantly improved. 
       FIG. 7  illustrates an exemplary injection molding configuration  300  for the manufacturing of the ball bearing clusters in accordance with one embodiment of the present invention. The arrangement of  FIG. 7  enables a mold configuration that produces an appropriate quantity of parts for a bar gun in a single mold.  FIG. 7  shows that the same mold may be used to produce retainer plates  280  that connect butterfly plate  210  with bar gun handle  230 . By molding a proper ratio of retainer plates  280  versus ball bearing clusters  240 , all the butterfly plate retainers and all the ball bearing clusters that are needed for a particular bar gun can be molded in one step. 
     As will be understood by those skilled in the art, the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. For example, the ball bearing cluster may be used in dispensing tools other than the bar guns. The ball bearing cluster may have ball-shaped projections of various sizes or not distributed symmetrically along a centerline. Furthermore, the ball-shaped projections may be non-spherical. Many other embodiments are possible without deviating from the spirit and scope of the invention. These other embodiments are intended to be included within the scope of the present invention, which is set forth in the following claims.