Abstract:
A sanitary faucet with a foam control feature adaptable for dispensing pressurized fluids. The sanitary faucet includes a valve body, a plunger assembly, a flow restrictor assembly and an adjusting screw assembly. Also disclosed is a method of variably regulating fluid flow pressure and the production of foam in the sanitary faucet.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application seeks priority from a Patent Cooperation Treaty Application PCT/US03/036036, which was filed on Nov. 12, 2003 with the United States Receiving Office, which in turn seeks priority from U.S. Provisional Patent Application No. 60/425,528 filed on Nov. 12, 2002, both of which are incorporated herein by reference in its entirety for all purposes. 
     
    
     BACKGROUND OF INVENTION  
       [0002]     The present invention relates to faucets for use with beer tappers and other pressurized dispensers and, more particularly, relates to a sanitary flow control faucet configured to dispense materials in a regulated manner with a foam control feature.  
         [0003]     Dispensing faucets are used in a variety of applications in which materials are dispensed from pressurized containers or other pressurized sources. Dispensing faucets of this type are widely used in beverage dispensing applications in which beer, soda, or another beverage is dispensed from a pressurized container such as a keg. They are also sometimes used to dispense condiments such as relish or mustard from containers under pressure. Indeed, the applications are many and may vary widely.  
         [0004]     A typical prior art faucet includes a valve operated by a pivotable lever. Specifically, a valve element is mounted on a plunger that is slidable longitudinally through a bore. When the lever is pivoted forwardly, towards the user, to open the valve element, the valve element moves rearwardly through the bore, thereby permitting dispensed materials to flow from the inlet of the valve to the outlet. The entire valve is exposed to flowing fluid during dispensation, but when the valve is not dispensing, major portions of wet valve elements are exposed to air. Standing fluid in the valve and exposure of the wet valve elements to air can give rise to undesirable bacterial growth within the valve. Some prior art faucets have overcome undesirable bacterial growth by positioning the plunger substantially at the outlet of the faucet, such that the great majority of the wet valve components are not exposed to air at any time.  
         [0005]     Foaming is produced in the process of dispensing certain pressurized fluids through these faucets. Foaming however, occasionally alters the taste and appearance of certain fluids, such as beers. Further, foaming may not be desirable when the fluid is being dispensed, but may be desirable when the fluid needs to be to topped off in a container, such as a mug. Therefore, the need has arisen to improve the design of a faucet to introduce controlled foaming in dispensed fluid, while not exposing the wet portions of the faucet to bacterial growth.  
         [0006]     Dispensable fluids, for example beers, are at times stored in sealed kegs, that is, under conditions that can lead to changes in pressure. In fact, many kegs that are put under pressure when filled with draft beer are stored in rooms with frequent temperature changes. Variation in temperature results in variation in pressure inside these kegs. In order to re-balance the pressure and control the fluid flow during dispensing, certain prior art dispensing faucets have compensator units. These compensator units, however, have limited control over balancing and regulating pressurized dispensing fluids. Uncontrolled or poorly controlled pressure exerted by these fluids ultimately leads to greater wear and tear of the faucet equipment. Also, regulating pressure via the use of compensators is not effective because these regulators may be positioned in limited orientations, resulting in limited regulation of pressure. Therefore, the need has arisen to improve the design of a faucet to provide improved regulation of pressure.  
         [0007]     Traditional faucets also require a fairly elaborate method for cleaning the valve elements, including taking the valve elements out of the valve body and washing them at another location. The need has arisen to provide valve elements that not only remain clean, but that also can be cleaned effectively without disassembling the valve.  
       SUMMARY OF INVENTION  
       [0008]     The present invention provides a sanitary dispensing faucet with a number of advantages. One advantage of the present invention is that the interior of the valve does not contain substantial amounts of air under normal usage, thereby limiting bacterial growth inside the faucet.  
         [0009]     Another advantage of one embodiment of the present invention is a push-back foam feature, such that controlled foam may be created, when required or as desirable.  
         [0010]     Another advantage of the present invention is a flow restrictor with a flow adjustment screw such that the pressure created by the contained fluid may be graduated and regulated at numerous levels.  
         [0011]     Yet another advantage of the present invention is that valve elements may be cleaned efficiently without significant disassembly of the valve.  
         [0012]     Generally the sanitary faucet includes (a) a valve body having a valve bore that has axially aligned inlet and outlet ports; (b) a plunger assembly substantially disposed in the valve body between the inlet and outlet ports; (c) a flow restrictor assembly; and (d) an adjusting screw assembly.  
         [0013]     In one embodiment, the flow restrictor assembly includes a shank that has a first and second shank end. The first shank end is removably attached to the inlet port of the valve body, while the second shank end is removably attached to a source of the dispensing fluid. The flow restrictor assembly further includes a flow restrictor member movably disposed within the shank. The flow restrictor has a funnel head that communicates with the plunger assembly, and a fluted tail having at least one groove or channel for permitting flow of inflowing dispensing fluids from the source. In a preferred embodiment, the adjusting screw assembly regulates movement of the flow restrictor assembly within the shank.  
         [0014]     Another aspect of the present invention includes a method for reducing foam from a dispensing liquid. The method is practiced by first attaching a source of the dispensing fluid to the inlet port of the valve body. The adjusting screw assembly is then rotated so as to move the flow restrictor such that the fluid entering the valve body has a desired level of pressure. Fluid at a desired pressure is then permitted to enter the plunger assembly. Finally, the handle assembly is moved to open and close the valve as desired. When the handle assembly is moved forwardly, the plunger assembly in turn is moved rearwardly. This movement opens the valve by opening a passage for the fluid that flows through at least one groove or channel of the fluted tail, over the funnel head, around the plunger assembly, towards the outlet port and out of a spout attached to the outlet port. Fluid dispensed by use of this method has a closely controlled pressure, and therefore results in the fluid being dispensed substantially without foam.  
         [0015]     Another embodiment of the method aspect of present invention provides a method for creating foam from a dispensing liquid that has the capability of forming foam, such as beer. According to this method, a source of the dispensing fluid is attached to the inlet port of the valve body. Fluid is permitted to enter the faucet at a desired pressure. The handle assembly is then moved rearwardly, which results in the plunger assembly being moved forwardly, which results in the larger passage for the fluid being closed. The handle assembly is then moved even further rearwardly against the force of a spring, which has the effect of exposing a transverse hole in a retaining screw beyond the valve seat. The beer, being forced through a small opening, becomes foamy.  
         [0016]     These and other advantages and features of the invention will become apparent to those skilled in the art from the detailed description and the accompanying drawings. It should be understood, however, that the detailed description and accompanying drawings, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0017]      FIG. 1  is an exploded perspective view of a faucet constructed according to one embodiment of the invention, depicting a flow restrictor with a flow adjustment screw and push-back foam feature.  
         [0018]      FIG. 2  is a sectional view of the valve body of the faucet shown in  FIG. 1 .  
         [0019]      FIG. 3 ( a ) is a plan sectional view of the faucet shown in  FIG. 1  showing a flow adjustment screw in a certain position, and a push back foam feature in an activated position.  
         [0020]      FIG. 3 ( b ) is a plan sectional view of the faucet shown in  FIG. 1  showing the flow adjustment screw in a different position than  FIG. 3 ( a ) and the faucet in its closed position.  
         [0021]      FIG. 4 ( a ) is a sectional view of the faucet shown in  FIG. 1 , showing the faucet shown in  FIG. 1  in its foam generating mode,  
         [0022]      FIG. 4 ( b ) is a sectional view of the faucet shown in  FIG. 1  showing the faucet in a closed position.  
         [0023]      FIG. 4 ( c ) is a sectional view of the faucet shown in  FIG. 1 , shown in an open position. 
     
    
     DETAILED DESCRIPTION  
       [0024]     A dispensing faucet is provided that is usable in any system in which a faucet is selectively operated to dispense materials from a pressurized source. For instance, it is applicable to “tapper” faucets configured to dispense beer or another pressurized liquid from a keg or another pressurized container. It is also applicable to condiment faucets configured to dispense ketchup, mustard or relish from a container. For the purposes of describing this invention, both non-viscous and viscous materials, such as beer and hot dog relish, shall be considered fluids or liquids.  
         [0025]     The faucet comprises a valve body and a plunger which is mounted in a bore in the valve body for reciprocating movement therein. The bore has an inlet port that opens into a passage adapted for connection to a pressurized container or other source of pressurized fluid, and an outlet port that opens into a dispensing spout adapted to deliver the fluid from the faucet. A handle having a pivotable lever is disposed partially within the valve body and terminates within a socket provided for that purpose in the plunger. The lever thus engages the plunger to drive the plunger to reciprocate longitudinally through the bore. A plug on the plunger interacts with a valve seat inside the valve body to control the flow of fluid through the valve.  
         [0026]     Referring specifically now to  FIGS. 1, 2 ,  3  and  4 , a faucet  10  constructed in accordance with a first embodiment of the invention includes a valve body  12  having a bore  14  within it, a spout  16  that is mounted on the valve body  12 , and a handle  18  that is operable by an operator to move a plunger  20  within the bore  14  to open the faucet  10  and dispense fluids through the spout  16 .  
         [0027]     The valve body  12  may be formed from any material capable of withstanding the pressures involved, slidably receiving the plunger assembly  20  and pivotably supporting the handle  18 . It preferably is formed from stainless steel, a food-grade plastic or another moldable material. The bore  14 , which is most preferably circular in cross-section, is formed axially through the valve body. In one embodiment of the present invention, an inlet port  22  comprises the upstream axial end of the bore  14  for connecting the faucet  10  to a pressurized fluid container (not shown). An outlet port  24  comprises the opposite end of the bore  14  for delivering dispensed fluid to the spout  16 . A valve seat  26  is located at a reduced-diameter portion of the bore  14  located adjacent or at the outlet port  24 . A bonnet bore  28  extends radially from the bore  14 , through a boss  30  on the upper surface of the valve body  12 , and to the outer surface of the valve body  12  for receiving the handle  18 .  
         [0028]     The lower end of the handle  18  forms a pivotable lever  32  that includes a partial ball  34  which engages a corresponding socket  36  of the plunger assembly  20 . The lever  32  is pivotably mounted in the bonnet bore  28  by a pivot mount, preferably formed from a second ball  38  and a bonnet socket  40 . Both balls  34  and  38  are preferably molded integrally with the lever  32 . The plunger socket  36  preferably is formed of a slot in the plunger  20 . The bonnet socket  40  is formed from a bonnet washer  42 , an upper bearing cup  44 , a lower bearing cup  46 , and at least one O-ring  48 . The assembly is held in place by a compression bonnet  47  threaded onto the boss  30  so as to capture the bonnet washer  42 , bearing cups  44 ,  46  and O-ring  48  beneath itself and within the bonnet bore  28 . This construction is described in more detail in the specification of application Ser. No. 10/142,751, filed May 9, 2002, the disclosure of which is hereby incorporated herein by reference.  
         [0029]     The plunger assembly  20  includes a plunger member  60 , slidably mounted in the bore  14 . The plunger member  60  is formed generally in the shape of a geometric solid, of a cross-sectional shape different than the cross-section of the bore  14 , so that the differences in cross-section create openings for permitting the passage of the fluid. The plunger member  60  includes an outer peripheral surface  54  and upstream and downstream axial ends  56 ,  58 . The above-described slot or socket  36  extends radially into the plunger  20  between the ends  56  and  58 . The entire plunger  20  is arranged within the bore  14  such that nearly the entire plunger  20  is always immersed in the liquid being dispensed, even when the faucet  10  is not in use. This is advantageous because no part located within the bore  14  is exposed to the air outside the faucet when constantly surrounded by fluid and enclosed within the valve body  12 .  
         [0030]     The plunger assembly  20  of this embodiment is contemplated for use with non-viscous fluid, such as beer or another beverage. The plunger assembly  20  is therefore configured to facilitate fluid flow through and past the plunger assembly and the interconnection between the plunger member  60  and the lever  32  so that the plunger assembly is washed clean of any particulate matter during dispensing. Most preferably the plunger member  60  is formed with a substantially square cross-section, creating four gaps between itself and the circular-shaped inside cross-section of the bore  14 . These gaps act as four channels of passage for the fluid to flow. Other shapes may also be used for both of these elements, so long as sufficiently substantial channels of passage are still formed thereby.  
         [0031]     One embodiment of the present invention includes an assembly to provide a foam control feature, for use with a beer dispensing faucet in those instances where foam is desirable. The foam control feature provides only foam, in such instances as where the user has dispensed nearly a full beer, without raising much foam, and wants to provide an attractive head to a glass of beer. In this embodiment, the plunger  20  is constructed of a valve stem  60  with a recoiling system that comprises a seal  62 , a seal retainer screw  64  which passes through the seal, a spring cup  66  and a coil spring  68 . The seal retainer screw  64  is threaded into an axial boss  70  at the end of the valve stem that faces toward the valve seat  26  inside the valve body  12 . The boss  70  includes an axial hole  71  formed therein, which aligns with an axial hole  64   a  formed in retainer screw  64 . The axial hole  64   a  enters the retainer screw  64  at the threaded end, but dead ends just before the head of the retainer screw  64 . A transverse hole  64   b  is formed just under the head of the retainer screw  64 , to intersect with the axial hole  64   a  and provide an exit from the axial hole.  
         [0032]     The retainer screw  64  and the seal  62  function as the valve closure. The seal  62  is mounted on the downstream end portion of the plunger member  60  for sealing against the valve seat  26  on the valve body  12  when the plunger member is in the non-dispensing, valve-closed position. In the most preferred embodiment, the seal  62  is a deformable elastomeric O-ring (on the order of 70-90 durometer) sized so as to matingly fit with the valve seat  26 .  
         [0033]     The retainer screw  64  and the seal  62  may be manufactured from any food grade material. In one preferable embodiment, the retainer screw  64  is made of stainless steel and the seal is made from any food grade polymer. The recoiling system of the plunger is effected when the seal  62  and the retainer screw  64  are inserted into the axial boss  70  as described above, through the spring cup  66  and coil spring  68 . The spring  68  is fitted such that it is capable of compression and expansion between the spring cup  66  and the downstream valve stem end  58 . As shown in  FIG. 4 ( c ), in a preferred embodiment, when the handle  18  by means of the pivotable lever  32  is positioned inside the socket  36  of the plunger member  60  and moved to a dispensing or forward position, the plunger assembly  20  moves away from the valve seat  26 , allowing a clear, foam-free fluid to be dispensed. On the other hand, as shown in  FIG. 4 ( b ), when the handle  18  is moved rearwardly to a non-dispensing position, the plunger assembly  20  moves forward to engage the valve seat  26  and substantially close the valve  10 , thereby preventing the flow of fluids. In this embodiment, as shown in  FIG. 4 ( a ), the handle  18  may also be positioned in a further backward position. When the handle  18  is put in the further backward position, the recoiling system is engaged and the spring  68  compresses axially between the bushing  66  and downstream valve end  58 . This action has the effect of exposing the transverse hole  64   b  in the retaining screw  64  beyond the valve seat  26 , as shown in FIGS.  3 ( a ) and  4 ( a ). The beer, being forced through the small openings of holes  71 ,  64   a  and  64   b , becomes foamy. The user is thus able to provide foam to top off a glass of beer with a nice head without which the glass would not be as attractive. Each of the holes  71 ,  64   a  and  64   b  have diameters of a size to create smooth foam for the particular beer being dispensed. In the experience of the inventors, diameters on the order of about 0.005 inches to about 0.09 inches provide the best functionality, but other diameters are also functional.  
         [0034]     The spout  16  is removably mounted on the downstream end of the valve body  12 , preferably by being threaded onto a threaded boss  76  extending downstream from the downstream end of the valve body  12 . The spout  16  is sealed against the valve body  12  by an O-ring  78 , which is mounted in a groove  80  on the upstream axial end of the spout  16 . Due to this rotation relationship, removal of the spout  16  renders all components of the faucet  10  that are exposed to fluid but not permanently immersed in it (namely, the valve seat  26 , the end of the retainer screw  64 , and the interior of the boss  76 ) accessible for easy cleaning by use of a simple swab or sprayer (not shown).  
         [0035]     In one embodiment of the present invention, the faucet  10  further includes a flow control mechanism, to closely control the flow of the dispensed fluid. As shown in FIGS.  1 ,  3 ( a ) and  3 ( b ), the flow control mechanism includes a flow control shank  82 , having formed therein a shank bore  84 , which is capable of being connected to a pressurized fluid container (not shown) via a boss  85 . Preferably, the boss  85  is connected to the pressurized container via a threaded connection. The interior of the bore  82  is essentially funnel-shaped and is designed to substantially fit a flow restrictor  86 , which has a narrow solid funnel head  88  and a solid fluted tail  90 . The shank  82  and the flow restrictor  86  are both preferably made of stainless steel. The head  88  of the flow restrictor  86  further comprises at least one orifice  92  providing an opening through the solid funnel head  88  and leading into a central chamber  94  of the funnel head  88 . It is preferred that head  88  further comprises at least four equally spaced orifices  92 , all in fluid communication with the central chamber  94 .  
         [0036]     The shank  82  containing the flow restrictor  86  is positioned relative to the bore  14  in the upstream end of the inlet port  22  with the aid of a keeper spring  96 , a keeper ring  102  and a ferrule  100 . The ferrule  100  is preferably connected to the inlet port  22  by any suitable removable connection such as threading, thereby trapping the head of the flow restrictor  86  inside the valve body  12 .  
         [0037]     The inlet valve  22  further comprises an angled bore  105  for receiving a flow adjusting screw  106 . The bore  105  is positioned, and the screw  106  sized, so that the end of the screw may contact the head of the flow restrictor  86 . In this manner, rotation of the flow adjustment screw  106  controls the amount of axial displacement of the flow restrictor  86  to a very fine degree of adjustment, providing very closely regulated flow control.  
         [0038]     The adjusting screw  106  may be of a conventional type with a knurled head, or, alternatively, may be provided with a tamper resistant flow adjustment screw head  108  and an adjusting key  112 , which are axially fitted with each other. An O-ring  110  may also be provided to reduce leakage around the adjusting screw  106 . Preferably, the screw end  108  and the adjusting key are made from stainless steel and the O-ring is made from elastomeric material. The angled bore  105  on the inlet valve  22  is positioned at a slanting angle, preferably 45o to the inlet valve. When the adjusting key  112  or knurled head is rotated clockwise, the screw end  108  enters further inside the bore  14  of the inlet valve  22 .  
         [0039]     In operation, as illustrated in the preferred embodiment shown in FIGS.  1 ,  3 ( a ) and  3 ( b ), when the shank  82  containing the flow restrictor  86  is coupled with the inlet valve  22 , then the flow restrictor  86  is positioned such that it may partially slide inside the bore  14  in the valve. As the adjusting key  112  is rotated, the adjusting screw  106  enters further inside the bore  14  of the inlet valve  22  via the angled bore  105 . The screw  106  constricts the movement of the flow restrictor  86  inside the bore  14 . When the adjusting screw  106  is gradually rotated clockwise, as shown in  FIG. 3 ( a ), the movement of the flow restrictor  86  is gradually constricted. The adjusting screw  106  is capable of at least 360-degree rotation, thereby allowing for very finely controlled movement of the flow restrictor  86 .  
         [0040]     When the pressurized fluid coming from upstream into the inlet port  22  has higher than desirable pressure, the adjustment screw  106  is rotated clockwise to constrict the movement of the flow restrictor  86 , which in turn restricts the fluid flow. On the other hand, if the pressure of the fluid is lower than desirable, then more fluid can be allowed to flow through the faucet  10  by simply gradually turning the adjustment screw  106  counter-clockwise to effect a desirable pressure-flow of the fluid, as shown in  FIG. 3 ( b ).  
         [0041]     Preferably, as shown in  FIGS. 1 and 4 , the fluid will enter the shank  82 , will pass along the fluted tail  90 , will enter the central chamber  94  of the head  88  via the orifices  92  and then will pass through bore  14  into the channels of passage surrounding the plunger assembly  20 . If the plunger assembly  20  is in a dispensing position, the valve  10  would open and fluid of desirable pressure and clarity will be dispensed, as shown in  FIG. 4 ( c ). If the plunger assembly  20  is a non-dispensing position, the fluid would fill the bore  14 , and the plunger assembly, including its parts as described above, will be immersed in the fluid without any exposure to air or bacterial growth, as shown in  FIG. 4 ( b ). Further, as shown in  FIG. 4 ( a ), the fluid entering the shank  82  may be forced through the plunger assembly  20  in a partially open foam-making position. Positioning the handle  18  in a push back foam generating mode, creates foam to top off fluids, such as beer with a head.  
         [0042]     Thus, although the invention has been herein shown and described in what is perceived to be the most practical and preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above. Rather, it is recognized that modifications may be made by one of skill in the art of the invention without departing from the spirit or intent of the invention and, therefore, the invention is to be taken as including all reasonable equivalents to the subject matter of the present invention.