Abstract:
A lightweight beer dispensing system comprising a small carbon dioxide pressure bottle attached directly to an adjustable pressure regulator that can be set to avoid excess foaming is attached directly to a keg tap having a delivery faucet. The invention taps a full size beer keg and uses CO 2  to keep the beer fresh thus avoiding the problem of introducing oxygen into the beer keg.

Description:
FIELD 
   The present invention relates generally to an apparatus used to tap beer kegs and dispense beer. More specifically the present invention relates to a lightweight portable beer keg tap and beer dispenser operated by CO 2  gas from a compressed gas cylinder. 
   BACKGROUND OF THE INVENTION 
   We can trace the beginning of beer drinking far back beyond the dawn of recorded time. Most likely, a crude form of beer was discovered by accident when someone mixed barley with water and then let it sit long enough for stray yeast cells to settle, triggering fermentation. The Babylonians, Assyrians, Egyptians, Hebrews, Africans, Chinese, Incas, Teutons, Saxons and various wandering tribes all discovered beer by various independent means. The dispensing system used by these early brewers were amphora, mugs and the early equivalent of straws, which were used to sip the liquid beer while avoiding the brewer&#39;s residue. 
   From the middle ages, when the use of hops made beer clear, until the 1890&#39;s, beer was stored in and dispensed from wooden barrels through simple valves and delivered to the drinker mug or glass by gravity flow. From the 1950&#39;s to the present most draft beer has been shipped in and dispensed from kegs that are cylindrical, made of stainless steel or aluminum and contain an extractor tube. 
   To dispense the beer from the keg a pressurizing gas, air or CO 2 , is forced into the keg through a beer keg tap. The liquid beer is forced out through the extractor tube, flexible hoses and a delivery faucet. Air is very undesirable as a pressurizing gas because the oxygen in air makes beer quickly go stale or sour. Air can be used when the entire keg is to be drunk quickly. Air cannot be used as a pressurizing gas if the keg must be stored and the beer consumed over a period of time. 
   There are two general types of beer dispensing systems taught by the prior art. One is a commercial system that uses heavy pressure bottles of compressed carbon dioxide gas operating through regulators and pressure lines to pressurize one or more kegs. The other is a consumer system usually used at a party or picnic that uses an air pump, which may be a hand powered or electrically operated compressor, to pressurize the keg. This is therefore commonly known as a picnic pump system. 
   Advantages of the commercial beer dispensing systems include the use of CO 2  dispensing systems that prevent air from coming in contact with the keg beer and thus allowing the keg beer to stay fresh for a longer period of time than when air is used as a pressurizing gas. Another advantage of a commercial beer dispensing system is the ability to control the pressure of the gas supplied to the keg through the use of adjustable regulators and pressure gauges. This feature is a marked advantage over a picnic pump system as it allows the pressure to be finely tuned to the individual type of beer or the specific temperature of the keg to prevent excessive foaming of the dispensed beer as is often encountered in the picnic pump systems. 
   Examples of commercial beer dispensing systems may be found in most bars and restaurants. This equipment is cumbersome and industrial. Their ‘rat&#39;s nest’ of tubing is a common feature behind bars. These commercial CO 2  dispensing systems weigh hundreds of pounds and can operate dozens of beer keg taps and draft beer dispensers. This equipment is completely unsuitable for use at picnics, parties or for the large and growing number of drinkers who wish to keep a keg of beer at home in their refrigerator so they can have draft beer at home on demand. 
   Picnic pumps such as the one taught by U.S. Pat. No. 4,711,377, issued to Brown on Dec. 8, 1987 use a hand-operated air pump. Such pumps are common and exist in hundreds of variations. These pumps are small and lightweight, but they pressurize the beer keg with air, which makes them unsuitable for use with a home keg because contact with the oxygen in air quickly ruins the beer. 
   U.S. Pat. No. 5,785,211 teaches a portable electrically powered keg-tapping device for use with regular beer kegs. The electrical compressor is a good replacement for a hand pump, but it does not solve the problem of introducing air into a keg that must be stored and used over a period of time. 
   An advantageous beer pumping system would combine the beer preservation and adjustable pressurization available with commercial type systems with the low profile and portability of a picnic pump system. Portable beer dispensing systems, such as the one taught by U.S. Pat. No. 5,199,609, issued to Ash on Apr. 6, 1993, teach the use of a CO 2  bottle packaged in a backpack and connected by pressure tubes to a container of beer. This type of dispenser, and there are many examples in the prior art, is useful for dispensing beer at sporting events, but uses a special small beer tank and thus cannot be of any use to home beer keg owners. 
   Another portable beer dispensing system, U.S. Pat. No. 2,571,433, issued to Fine et al. on Oct. 16, 1951, teaches the use of a small pressurized cylinder and a regulator permanently attached to a specialized beer container. However, the specialized beer container is not commercially available. Furthermore the pressurization system is permanently attached to the non commercially available specialized beer container. Additionally, the presence of a cover over the pressurization system does not facilitate precision pressure adjustments for individual types of beer or specific keg temperatures to prevent unwanted foaming. A more useful device will combine all the advantages of a commercial beer pumping system, such as CO 2  pressurization to maintain beer freshness and easy adjustability of the CO 2  pressure to prevent foaming, with the low profile and portability of a picnic pump system. Interestingly, no devices that incorporate all the advantages of a commercial beer pumping system with the low profile and portability of a picnic beer pumping system currently exist. 
   This combination would allow for a simple home draft beer system by placing a small, easily adjustable CO 2  pressurized beer pump on any commercially available beer keg. The keg with the beer pump could then be placed in any conventional refrigerator for to keep the beer at a constant drinkable temperature. Currently, home kegs may be kept in refrigerated one keg systems, such as the Beer Baron® sold by Ajex USA, Inc. of Commerce City, Colo., but such “home” draft beer systems are huge, weigh several hundred pounds and are very expensive. 
   U.S. Pat. No. 4,180,189, issued to Zurit et al. Dec. 25, 1979 teaches the use of a standard keg tap using a conventional bayonet type of connection to attach the tap to the keg. In addition U.S. Pat. No. 4,180,189 also teaches the use of a pressure inlet to pressurize the beer keg in combination with a Thomas valve designed to prevent back pressure or beer from flowing out of the pressure inlet into the pressure producing source. However, the incorporation of a Thomas valve to help prevent back pressure or beer into the pressure producing has not been rigidly attached to a regulator and a rigidly attached gas canister designed for kegs to be stored in a home refrigerator. The Thomas valve in U.S. Pat. No. 4,180,198 would be designed to prevent back pressure or beer from flowing into a flexible tube used to deliver pressure to the tap, thereby preventing damage to the flexible tube. A desirable invention, in combining all the advantages of a commercial beer pumping system with the low profile and portability of a picnic beer pumping system would have a Thomas valve directly attached to a check valve and furthermore to an easily adjustable pressure regulator and finally attached to a pressurized CO 2  canister. 
   It is applicant&#39;s belief that none of the above prior art systems have received commercial recognition because they either are too expensive to construct, or are not reliable. None of the above prior art systems solve the problems facing the home keg owner who wishes to tap the keg and still keep the beer fresh over an extended period. 
   SUMMARY OF THE INVENTION AND ADVANTAGES 
   The invention is a beer dispensing system comprising a beer tap connected directly to an adjustable pressure regulator and a small CO 2  pressure bottle. The present invention combines the advantage of the commercial CO 2  beer dispensing system of operating with a full sized beer keg and keeping the beer fresh over a long period with the advantages of the small, lightweight, simple and convenient air operated party pump. 
   Yet another advantage of the present invention is that it provides a lightweight and small CO 2  operated beer-dispensing system that does not require the use of cumbersome hoses and pressure tubes. 
   Another advantage of the present invention is that it provides a beer dispensing system that will operate with a standard keg in a regular home refrigerator. 
   Yet a further advantage of the present invention is that it provides a CO 2  powered beer dispensing system that is small, lightweight, inexpensive and reliable. 
   Another advantage of the present invention is that it provides for precision adjustability of the pressure regulator, allowing the user to adjust the pressure of the beer tap for each individual type of beer or specific temperature of the keg, thus preventing the uncontrolled foaming that is often encountered with the picnic pump systems. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows the major components of the portable beer delivery system of the present invention with the individual parts separated for clarity; and 
       FIG. 2  shows the present invention mounted on a beer keg that is stored in a home refrigerator. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  shows the components of the present invention and how they fit together. The components are shown separated for clarity. 
   In  FIG. 1 , aluminum alloy CO 2  cylinder  101  is a 16-ounce capacity 800 p.s.i. cylinder that is commercially used to power paint ball guns. It is available from Catalina Cylinders of Trumann, Ariz. They are inexpensive and safe. 
   Structurally, outlet  102  of cylinder  101  is attached to and in fluid communication with the inlet of needle valve  103 , which is commercial low-pressure needle valve. Valve  103  has a threaded outlet  105  that is connected to and in fluid communication with the threaded inlet  107  of pressure regulator  111  by means of pressure regulator inlet pipe  109 . Pressure regulator  111  may be any commercial pressure regulator capable of accepting an input pressure of 800 PSI and producing an easily adjustable variable output pressure of from zero to 50 PSI. One example is the model 03G07-222 forged brass regulator sold by the Foxx Equipment Company of Kansas City, MO. (“Foxx”). Regulator  111  is equipped with two pressure gauges, a low pressure gauge  112 , designed to measure the pressure within the keg, and a high pressure gauge  114 , designed to measure the pressure of the gas cylinder. Regulator  111  is also designed so that the pressure in the keg and the corresponding readout of the low pressure gauge  112  may be varied for each individual type of beer. This is accomplished by simply turning an adjustment device on the regulator  111  to the desired keg pressure. Regulator  111  also has its outlet  113  in threaded connection and fluid communication with inlet  115  of check valve with nipple  117 . Check valve  117  may be a model 03G07-232 brass check valve sold by Foxx. The outlet nipple  119  of check valve  117  mates in fluid communication with rubber Thomas valve  121  and is threadingly attached to and in fluid communication with pressurization inlet  123  of beer keg tap  125 . Beer keg tap  125  may be a universal twist style Sanke Tap® model number 07S07-102 available from Foxx. Beer tap  125  has a standard beer keg tap pressure fitting  127  that is adapted to operable engage a standard beer keg, not shown. Beer tap  125  also has a beer outlet  128 . Beer outlet  128  is connected to and in fluid communication with flexible beer hose  129  and beer delivery faucet  131 . Beer dispensing faucet  131  is attached at its inlet to and in fluid communication with beer hose  129 . Beer dispensing faucet  131  is a standard hand-dispensing faucet having a hand-operating lever  133  and an outlet spout  135  for the delivery of the beer to a cup or glass, not shown. Faucet  131  may be a model 18A03-102 sold by Foxx. 
   Functionally, the high pressure CO 2  gas in cylinder  101  passes through needle valve  103  and into pressure regulator  111  where it is reduced in pressure from 800 PSI to about 20 PSI. The low pressure CO 2  then passes out of regulator  111 , through check valve  117 , Thomas valve  121  and beer tap  125  into the beer keg, which it pressurizes in a well-known manner. Beer from the keg flows out through beer tap outlet  128 , through flex tube  129  to faucet  131  where it is dispensed to the drinker. 
   The entire invention including the CO 2  weighs less than six pounds and can be used to tap beer from any standard keg. 
     FIG. 2  shows the present invention used as a tap for a beer keg in an ordinary kitchen refrigerator. In  FIG. 2 , refrigerator  201  contains a beer keg  203 . The portable beer keg tap and dispenser of present invention  205  is shown tapped into the keg. CO 2  tank  207  is attached to valve and regulator and tap assembly  209 , which is attached to keg  203 . Flex line  211  and faucet  203  are attached to tap assembly  209 . Depicted on the tap assembly is the low pressure gauge  112 , designed to measure the pressure within the keg, and the high pressure gauge  114 , designed to measure within the gas cylinder. The refrigerator keeps the beer cold so it will not produce excess foam when it is dispensed. The present invention may operate as shown, vertically, or with the keg laid sideways in the refrigerator and with an insulating barrier placed between the keg and the front of the refrigerator. This embodiment of the invention hides the keg and the dispensing systems so only flex line  211  and faucet  213  is visible. This provides a neat and convenient home draft beer dispenser that would keep the beer fresh; just a commercial system does in a bar. 
   Beer must be maintained above freezing and below 42° F. in order to maintain proper freshness and carbonation. The chart below gives the target CO 2  pressure to be set on the regulator for various temperatures to allow 6 weeks of perfectly carbonated beer. Beer is best stored and served below a 40° F. keg temperature. 
   
     
       
             
           
             
             
             
             
             
             
             
           
         
             
                 
             
             
               Keg Temperature &amp; Pressure Chart (for all 100% CO 2  Systems) 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
               Keg 
               35 
               37–38 
               38–39 
               40 
               41–42 
               43–44 
             
             
               Temperature 
             
             
               (° F.) 
             
             
               Internal Keg 
               10 
               11 
               12 
               13 
               14 
               15 
             
             
               Pressure 
             
             
               (pounds) 
             
             
               Minimum 
               13 
               14 
               15 
               16 
               17 
               18 
             
             
               Applied 
             
             
               Pressure 
             
             
               (pounds) 
             
             
               Maximum 
               16 
               17 
               18 
               19 
               20 
               21 
             
             
               Applied 
             
             
               Pressure 
             
             
               (pounds 
             
             
                 
             
           
        
       
     
   
   Depending on the chemical composition of the beer, different beer brands may require various gas pressure adjustments to prevent foaming and to maximize pouring ability. Now more than ever, there is an increased demand for foreign beers with chemical compositions that often vary greatly from region to region. In addition, the explosion of microbreweries in the United States has also altered the once nearly uniform composition of beers available in this country. Standard American lager beers for example are composed of higher water content than that of popular English and Irish beers. The percentage of water in the beers affects the viscosity, and therefore affects the length of time needed for a beer head to settle after pouring at a given pressure. It is therefore necessary to adjust the pressure for each individual type of beer to provide for optimal pouring effectiveness. For example, standard American lager beers are poured at a pressure of 10–15 p.s.i., while many of the European beers require that they be poured at a pressure of 5–7 p.s.i. 
   Although this specification discloses the best embodiment of the invention known to the inventor, it should not be read as limiting the invention. The invention should be limited only by the appended claims and their equivalents.