BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to valve assemblies, commonly called “taps,” used to dispense beverages, particularly beverages stored under pressure, such as draft beer. 
     2. Description of the Prior Art 
     Many bars, taverns, pubs, ale houses and restaurants dispense beverages by means of pressurized storage and delivery systems controlled by valve assemblies commonly called “taps.” Taps, which may be mounted on a wall, or connected to a counter-top by means of a stanchion, communicate with storage containers of beverage via conduits and control the flow of beverage from the storage container to the receptacles in which the beverage is served. 
     Taps comprise a tap valve that is controlled by a tap-handle assembly. Most tap valves are actuated by a to-and-fro movement of a vertically-oriented tap-handle assembly, as described in detail below. In order to open the valve and dispense beverage, the tap-handle assembly is pulled forward, toward the server. To close the tap, the tap-handle assembly is pushed away from the server. 
     In addition to providing a mechanism for actuating tap valves, the exterior parts of tap-handle assemblies are shaped and painted in unique ways in order to indicate the brand of the beverage that is being dispensed from the tap. 
     SUMMARY OF THE INVENTION 
     Shortcomings of Prior Art That Are Overcome by the Invention 
     Taps of various types have been in use for many generations; however, they share one persistent shortcoming: they are difficult or impossible to operate with one hand. This shortcoming is particularly troublesome during periods when business is brisk because it is at such times that it is desirable to fill two receptacles simultaneously—holding one receptacle in each hand under separate taps—thus effectively doubling the rate at which beverage is delivered to the customers. However, many servers find it impossible to operate a tap with the same hand that holds the glass or pitcher to be filled. Even if two taps can be opened and two receptacles can be filled in this manner, it is often necessary to put down one receptacle that has been filled in order to have a free hand with which to close the taps. During this maneuver, beverage is lost due to spillage and over-filling. Consequently, over the course of a busy evening there is a substantial loss of beverage and a concomitant loss in profits. 
     For these reasons it would be desirable and commercially beneficial to have a means of opening and closing taps with one hand while holding the receptacle to be filled with that hand. 
     OBJECTS OF THE INVENTION 
     A first object of the invention is to provide a means and a mechanism for opening and closing a tap easily with one hand while simultaneously holding a receptacle with the same hand; 
     A second object of the invention is to provide a means and a mechanism for reducing the spillage of beverage that occurs when a server attempts to operate a tap with one hand; 
     A third object of the invention is to provide a means to identify the beverage that is being dispensed by a particular tap. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, features and advantages of the invention will become more apparent from the descriptions below, taken in connection with the accompanying drawings: 
     FIG. 1-A is a side elevation of a typical prior-art tap in the closed position, showing the components of the tap-handle assembly; 
     FIG. 1-B is a side elevation of the typical prior-art tap shown in FIG. 1-A, assembled and in the open position; 
     FIG. 2 is a side elevation of one embodiment of the invention showing the operation of the tap with the invention in place; 
     FIG. 3 is an isometric view of an embodiment of the present invention similar to that shown in FIG. 2, but with the addition of a display means; 
     FIG. 4-A is a side elevation of a tap showing the component parts of an improved tap handle, which is one embodiment of the present invention; 
     FIG. 4-B is a side elevation of a tap showing the improved tap handle of FIG. 4-A assembled; 
     FIG. 5-A is a side elevation of a tap showing the component parts of an improved upper retaining nut, which is one embodiment of the present invention; 
     FIG. 5-B is a side elevation of a tap showing the improved upper retaining nut of FIG. 5-A assembled. 
     All drawings are oriented so that the server would be standing to the right and beverage would flow though the tap from left to right when the tap is open. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
               
               
                 REFERENCE NUMERALS USED IN THE DRAWINGS 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 10 
                 tap-handle assembly 
               
               
                 12 
                 tap handle 
               
               
                 14 
                 upper retaining nut 
               
               
                 16 
                 handle-stud 
               
               
                 17 
                 lower retaining nut 
               
               
                 18 
                 piston 
               
               
                 20 
                 spout 
               
               
                 21 
                 faucet casing 
               
               
                 26 
                 retrofit tap-handle- 
               
               
                   
                 assembly extension 
               
               
                 28 
                 retrofit tap-handle 
               
               
                   
                 assembly extension 
               
               
                 30 
                 connector hole 
               
               
                 32 
                 display means 
               
               
                 40 
                 improved tap-handle 
               
               
                   
                 assembly 
               
               
                 42 
                 improved tap handle 
               
               
                 44 
                 tap-handle-assembly 
               
               
                   
                 extension 
               
               
                 45 
                 key 
               
               
                 46 
                 adapter bushing 
               
               
                 47 
                 key channel 
               
               
                 48 
                 cushion 
               
               
                 50 
                 modified upper- 
               
               
                   
                 retaining-nut assembly 
               
               
                 52 
                 modified upper retaining 
               
               
                   
                 nut 
               
               
                 54 
                 upper retaining nut 
               
               
                   
                 extension 
               
               
                 56 
                 upper-retaining-nut stud 
               
               
                 58 
                 annulus 
               
               
                   
               
             
          
         
       
     
    
    
     DESCRIPTION OF STRUCTURAL FEATURES AND FUNCTIONAL RELATIONSHIPS OF COMPONENT PARTS 
     FIGS. 1-A and  1 -B are side elevations of a typical tap, showing such a tap in the closed (FIG. 1-A) and open (FIG. 1-B) positions. 
     FIG. 1-A shows the various component parts of a tap that are relevant to the present invention. A cylindrical faucet casing  22  has a bore (not shown) through which beverage passes to the spout  20  when a ball-type valve (not shown) within the bore is open. A piston  18 , which is controlled by a tap-handle assembly  10 , travels to and fro within the bore of faucet casing  22 . The anterior end of piston  18  protrudes from the casing when the tap is in the closed position, as is depicted in FIG. 1-A. The posterior end of the piston (not shown) forms the ball of the ball-valve. When the tap is closed, this ball is seated against the faucet bore and the flow of fluid though the bore is occluded. When the piston with its ball-end is moved toward the rear of the tap by the forward movement of the tap-handle assembly  10 , the beverage flows through the valve, into the bore of the faucet casing  22  and out through the spout  20 . 
     Tap handle-assemblies may take a number of forms, but their function is the same; to act as a lever by which the server can open and close the tap valve. The exploded tap-handle assembly  10  shown in FIG. 1 is typical of the prior art. Tap-handle assembly  10  includes an externally threaded handle-stud  16  attached at its lower end (not shown) to piston  18 . An internally-threaded lower retaining nut  17  fits over the handle-stud  16  and mates with a externally threaded annulus  58  in the faucet casing. A second internally threaded retaining nut, referred to herein as the upper retaining nut  14 , is screwed onto the handle-stud  16  until it fits snugly against the lower retaining nut  17 , leaving part of the handle-stud extending past the upper surface of the upper retaining nut. An internally threaded tap handle  12  is screwed onto the remaining exposed part of the handle-stud  16 . (Only the lower portion of the tap handle  12  is shown in the diagrams.) 
     FIG. 1-B shows a fully assembled tap in the open position. By comparing FIG. 1-A to FIG. 1-B, it can be seen that the tap-handle assembly must be pulled forward approximately 10°-20° in order to open the tap valve. 
     Tap handles vary in size, shape and color according to the brand of beverage that is being dispensed, but they are typically elongate structures having an outside diameter of about 30 mm and a length of approximately 300 mm. Because tap handles have internally threaded connectors in their lower ends (not shown) that mate with the upper end of the handle-stud  16 , they can be readily removed and exchanged with one another. This permits the appropriate handle to be employed when a tap is connected to a keg containing a different brand of beer, the replacement handle then indicating the brand. 
     FIG. 2 depicts an embodiment of the invention in which a tap-handle assembly has been adapted with a tap-handle-assembly extension  26 . This embodiment of the invention has the advantage that no modification of the components of the tap-handle assembly is required because the prior-art-tap-handle assembly  10  shown in FIG. 1-A can be easily retrofit with tap-handle-assembly extension  26 . 
     FIG. 2 also shows the motion of the adapted tap-handle assembly as the tap is opened. This motion is characteristic of all embodiments of the invention, as discussed in the next section. 
     The tap-handle-assembly extension  28  shown in isometric view in FIG. 3 is the same as tap-handle-assembly extension  26  but modified by the addition of a display means  32 , discussed below. As can be seen, tap-handle-assembly extension  28  has a substantially horizontal upper portion and a substantially vertical lower portion. A wide variety of connectors are anticipated for attaching the tap-handle-assembly extension to the tap-handle assembly. The embodiment shown in FIG. 3 illustrates a simple connector: a connector-hole  30  that allows the tap-handle-assembly extension to be fitted over the handle-stud  16 . As shown in FIG. 2, the tap handle  12 , once screwed onto the handle-stud  16 , secures the tap-handle-assembly extension  26  against upper retaining nut  14 . 
     The embodiment of the invention shown in FIG. 3 includes a display means  32  attached to the lower portion of the tap-handle-assembly extension  28 . The display means is used to display small signs indicating the brand of the beverage being dispensed or other information, such as advertising. Such a display means can be incorporated in all embodiments of the invention. 
     FIG. 4-A depicts another embodiment of the present invention: a modified tap-handle assembly  40  in which a tap handle  42  is modified so as to have a tap-handle extension  44  incorporated into its structure. The adaptation of the tap handle can be better visualized by comparing the conventional tap handle  12  of FIG. 1-A with the modified tap handle  42  of FIG. 4-A. 
     A connector is required in this embodiment that will permit the attachment of the modified tap handle  42  to the tap-handle-assembly. Unlike the conventional tap handle, the modified tap handle  42  has no internal threads in its lower end. Rather, an internally threaded adapter bushing  46  is screwed onto the handle-stud  16  until the adapter bushing is flush against the upper retaining nut  14 . The tap handle  42  is then slid down onto the adapter-bushing  46 . A key-channel  47  in the adapter bushing  46  communicates with an internal key  45  in the handle  42 . This prevents the handle from rotating on the adapter bushing during operation of the tap. 
     FIG. 4-B shows the assembly tap-handle assembly of FIG. 4-A. It should be noted that the upper retaining nut  14  used in this embodiment is of the conventional type shown in the diagrams of the prior art at FIGS. 1-A and  1 -B. 
     FIG. 5-A depicts an upper-retaining-nut assembly  50  embodiment of the present invention in which the upper retaining nut  52  is adapted so as to receive a removable upper-retaining-nut extension  54 . The adaptation can be better visualized by comparing the conventional upper retaining nut  14  of FIG. 1-A with the modified upper retaining nut  52  of FIG. 5-A. The removable upper-retaining-nut extension  54  is substantially round in cross-section and has a hollow, internally threaded upper end by which it connects to the upper retaining nut  52  by a connector: an externally threaded upper-retaining-nut stud  56  that protrudes from the modified upper retaining nut  52 . (Alternatively, the upper-retaining-nut stud could protrude from the upper-retaining-nut extension  54  and mate with internal threads in the upper-retaining nut  52 .) 
     FIG. 5-B shows the embodiment of FIG. 5-A assembled. It should be noted that in this embodiment the beverage handle  12  is of the convenient type shown in the diagrams of the prior art at FIGS. 1-A and  1 -B, it being an advantage of this embodiment that the conventional tap handle need not be altered. 
     It will be noted that the various extension devices shown in FIGS. 2,  3 ,  4 -A,  4 -B,  5 -A and  5 -B have a curved lower end. In addition, FIGS. 4-A,  4 -B,  5 -A and  5 -B show how a rubberized cap or cushion  48  fitted to the lower end of the extension device, but which may extend well up the length of the extension device. Such a cushion is anticipated regardless of whether or not the lower end of the extension device is curved. 
     DESCRIPTION OF OPERATION OF THE INVENTION 
     From the prior art shown in FIGS. 1-A and  1 -B, the difficulty in operating a tap with only one hand may be appreciated. In order to open the tap, the tap-handle assembly must be pulled forward from the position shown in FIG. 1-A to the position shown in FIG. 1-B, while simultaneously holding the receptacle in position to catch the beverage that flows from the spout  20 . In order to do this, the server must hold the receptacle with four fingers, reach up with the index finger, wrap the index finger around the bottom portion of the upper retaining nut  14 , and pull the entire tap-handle assembly forward to the position shown in FIG. 1-B. When filling two receptacles, this complex maneuver must be carried out with both hands simultaneously. 
     Closing the taps after filling two receptacles is even more difficult. The server—now holding two full receptacles of beverage—must use each index finger to apply pressure to the forward aspect of respective lower retaining nuts  14  and thereby push the tap handle-assemblies away from the server. Not surprisingly, beverage is often split during this maneuver. For servers with small hands, closing two taps simultaneously is all but impossible, in which case the server must put down one of the full receptacles and use the free hand to quickly close both taps. Even when the server has large hands and enviable dexterity, some tap handles are so heavy that moving them to and fro with one finger is not easily done without spilling beverage. Consequently, a lot of beverage goes down the drain when servers attempt to fill two receptacles simultaneously to satisfy the demands of thirsty, inebriate customers. 
     By understanding the operation of the invention as shown in the preferred embodiments of FIGS. 2,  3 ,  4 -A,  4 -B,  5 -A and  5 -B the reader will discover how the invention overcomes the foregoing difficulties. 
     FIG. 2 shows a conventional tap-handle assembly modified by the addition of a retrofit tap-handle-assembly extension  26 , such as one  28  shown in isometric view in FIG.  3 . When such a tap-handle-assembly extension is fitted to a tap-handle assembly, it facilitates the difficult task of operating the tap with one hand while simultaneously holding a receptacle—the server simply presses down on the tap-handle-assembly extension to open the valve and pushes up on the tap-handle-assembly extension to close the valve. 
     The embodiments depicted by FIGS. 2 and 3 include a flared portion  34  of the lower end of the tap-handle-assembly extension that makes this action even easier. Downward pressure on the flared portion  34  causes the tap-handle assembly to tilt forward, thereby opening the valve. Once the receptacle is full, the edge of the receptacle is used to apply pressure to the back side of the tap-handle-assembly extension, as shown in FIG. 2, thus causing the end of the tap-handle-assembly extension  34  to move in an upward direction, the tap-handle assembly to move backwards, and the tap valve to close. In this manner even servers with small hands can move the tap-handle assembly to and fro easily. 
     It will readily be appreciated from FIG. 3 how the particularly simple and utilitarian form of this embodiment ensures its easy and economic construction from metal, plastic, rubber, or any rigid or semi-rigid material. 
     The retrofit tap-handle-assembly extension  28  shown in FIG. 3 demonstrates an additional useful feature: a display means  32 . Many embodiments of such a display means are possible and anticipated, for instance, a hollow placard holder having an open edge through which a small placard can be inserted, and a transparent face through which the placard can be seen. Alternatively, a solid ferrous structure may be employed to which a placard may be attached magnetically. Or a small “white-board” may be employed, upon which information can be written in erasable ink. It is also anticipated that the placard holder may have a self-contained battery or other source of power and a means for illuminating the placard and/or the tap. In any case, the function of the display is the same: to provide a means of using the tap-handle-assembly extension  28  to present information about the tap-system itself, such as “empty.” 
     FIG. 4-A and  4 -B illustrate an embodiment of the invention in which the tap handle  42  incorporates a tap-handle extension  44  in the structure of the tap handle. 
     One difficulty with this approach is that a tap handle with such a tap-handle extension cannot be screwed onto the handle-stud because during this operation the lower portion of the tap-handle extension is not able to get around the faucet casing  22 . In order to overcome this difficulty, a connector is required, such as adapter bushing  46 , which is provided with internal threads that mate with the threads of the handle-stud  16 . One assembles this embodiment by first screwing the upper retaining nut  14  down onto the handle-stud  16  so that it fits snugly against the lower retaining nut  17 . Next, adapter bushing  46  is screwed down onto the upper retaining nut  14 , and the modified tap handle  42  is slid down onto the adapter bushing. Unlike a conventional tap handle, the modified tap handle of this embodiment has a smooth, non-threaded bore so that it slides over the adapter bushing. In order to prevent the tap handle from twisting on the adapter bushing during operation, a key  45  is provided in the bore of the tap handle, which  45  engages a key channel  47  provided in the adapter bushing  46 . Tap handles that have been modified in this way can be exchanged quite easily by sliding them on and off of the adapter bushing. However, conventional tap handles can also be used by removing the adaptor bushing  46  from the handle-stud  16 . It should be noted that the handle-stud  16  and the upper retaining nut  14  are conventional and need not be modified in this embodiment. 
     FIG. 4-B shows this embodiment of the invention assembled. Pushing down on tap-handle extension  44  with but a single finger causes the entire tap-handle assembly  40  to move forward, thereby opening the tap valve. Pushing upwards on the back-side of tap-handle assembly  44  with the upper edge of the filled receptacle causes the entire tap handle assembly  40  to move backward, thus closing the tap valve. 
     FIGS. 5-A and  5 -B show another preferred embodiment of the invention: a modified upper retaining nut, including an upper-retaining-nut extension and a connector. In this embodiment, an upper-retaining-nut assembly  50  comprises an upper retaining nut  52  modified to receive a removable upper-retaining-nut extension  54 , which has internal threads in its upper end so that it can mate with an upper-retaining-nut stud  56  protruding from the upper retaining nut  52 . With this embodiment, the tap-handle assembly with the modified upper retaining nut  52  is assembled by removing upper-retaining-nut extension  54  from the upper retaining nut  52  and screwing upper retaining nut  52  onto the handle-stud  16  (shown in FIG. 1-A) so that it fits snugly against lower retaining nut  17 . The tap handle  12 , which is the conventional type shown in FIG. 2, is then screwed onto the handle-stud until it fits snugly against the upper retaining nut  52 . Finally, upper-retaining-nut extension  54  is replaced by screwing it onto the upper-retaining-nut stud  56 . The assembled tap-handle assembly is shown in FIG. 5-B. 
     The embodiment shown in FIG. 5-B operates in a manner that is identical to the embodiment shown in FIG.  2 . The tap is opened with one finger by pressing down on the lower end of upper-retaining-nut extension  54 . The tap is closed by using the edge of the receptacle to apply upward pressure to the back of upper-retaining-nut extension  54 . 
     An additional refinement of the invention demonstrated in FIGS. 4-A,  4 -B,  5 -A and  5 -B is a cushion  48  fitted to the lower end of the respective extensions  26 ,  44 , and  54 . Such a cushion may be made of any resilient, protective material, such as rubber or plastic. It is convenient and economically useful to have such a cushion—especially with embodiments of the invention cast in metal—to avoid the scratching, chipping or breaking of glass receptacles when using the edge thereof to turn the tap off, as discussed above. 
     SUMMARY, RAMIFICATIONS, AND SCOPE OF THE DISCLOSURE 
     Accordingly, the reader will appreciate how the invention disclosed herein facilitates the one-handed operation of taps. Furthermore, it will be appreciated that this invention provides a number of economic advantages: 
     it effectively doubles the rate at which beverages can be dispensed; 
     it permits all servers, large and small, to easily fill two receptacles simultaneously in spite of morphometric limitations of their digits; 
     it minimizes the shameful spillage and waste of valuable liquid commodities; 
     it provides a means for readily determining what beverage is being dispensed through which tap. 
     The foregoing descriptions disclose numerous details of how to make and use the invention; however, these descriptions should not be construed as limitations either of the scope or the anticipated embodiments of the invention but rather as disclosures of presently preferred embodiments of the invention. For instance, the connector used to connect the retrofit tap-handle-assembly extension shown in FIG. 3 to the tap-handle assembly could be a collar and set-screw mechanism, or the lower portion of the tap-handle-assembly extension shown in FIG. 3 could have a more oval or rounded cross-section. 
     Thus, the scope of the invention should be determined not by the preferred embodiments disclosed above, but by the following claims and their legal equivalents.
In a beverage tap of the kind used in ale houses, pubs and restaurants, a tap-handle-assembly extension is provided that facilitates the operation of the tap with one hand so that the server can easily fill two receptacles from two taps simultaneously without wasting beverage. Disclosed embodiments include an extension that may be reversibly retrofitted to an existing tap, an extension that is incorporated into the structure of a tap handle, and an extension that is connected to and contiguous with an upper retaining nut.