Patent Publication Number: US-11390513-B2

Title: Apparatus for dispensing a liquid from a liquid storage container

Description:
RELATED APPLICATIONS 
     The subject patent application is a continuation of U.S. patent application Ser. No. 15/388,429 filed on Dec. 22, 2016 which is a continuation of U.S. patent application Ser. No. 13/373,886 filed on Dec. 5, 2011, now U.S. Pat. No. 9,527,714, which is a continuation-in-part of U.S. patent application Ser. No. 13/137,606 filed on Aug. 29, 2011, now U.S. Pat. No. 8,887,955. Priority is claimed under 35 USC § 120 from U.S. patent application Ser. No. 15/388,429, U.S. patent application Ser. No. 13/373,886 and U.S. patent application Ser. No. 13/137,606. The entire contents of U.S. patent application Ser. Nos. 15/388,429, 13/137,606 and 13/373,886 are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed to a dispensing apparatus for dispensing liquid from a liquid storage container and a replaceable liquid transport assembly for conveying liquid between a liquid storage container and a dispensing location of the dispensing apparatus. The dispensing apparatus may dispense any suitable liquid including but not limited to chilled drinking water, hot water, ambient temperature drinking water, carbonated liquid and/or any combination thereof. The liquid storage container may include but is not limited to a replaceable five (5) gallon water bottle stored in a lower portion of the dispensing apparatus. In its most preferred form, the present invention is directed to a water cooler for dispensing at least chilled drinking water from a replaceable five (5) gallon water bottle stored in a lower portion of the water cooler in an upright orientation. 
     BACKGROUND OF THE INVENTION 
     A significant number of existing water dispensers use gravity as the driving force to dispense water from the water dispenser. In this type of water dispenser, the water bottle is positioned above the dispensing location. These dispensers are referred to as “Top-Loading” water dispensers. Top-Loading water dispensers typically include means for receiving a five (5) gallon water bottle at the uppermost portion of the water dispenser. Five (5) gallon water bottles are quite heavy making it difficult for some individuals to mount the water bottle on the uppermost portion of the water cooler. Top-Loading water dispensers typically dispense water for human consumption. Therefore, it is important that the water contact surfaces of the water dispenser be periodically cleaned. The cleaning process is generally known as “sanitization.” Top-Loading water dispensers typically are simple devices with few components in contact with the drinking water. Hence, the sanitization process is relatively easy. A number of Top-Loading water dispensers are designed to improve the sanitization process. U.S. Pat. Nos. 5,361,942 and 5,439,145 disclose Top-Loading water dispensers designed to improve the sanitization process. Ebac Limited sells Top-Loading water dispensers designed to improve the sanitization process utilizing at least some of the features disclosed in U.S. Pat. Nos. 5,361,942 and 5,439,145 including the removable manifold unit, reservoir and associated plastic or rubber tubing. This removable assembly is marketed under the Ebac Limited trademark WATERTRAIL. 
     To overcome the problems of Top-Loading water dispensers, water dispensers in which the water bottle is stored in the lower portion of the water dispenser have been proposed. Since these systems cannot rely upon gravity to dispense drinking water, pumps are typically employed to pump the drinking water to the dispensing location located above the water bottle. These types of water dispensers are referred to herein as “Bottom-Loading” water dispensers. An example of such a water dispenser is disclosed in U.S. Patent Publication No. 2005/0072813. Bottom-Loading water dispensers address the water bottle installation problems associated with Top-Loading water dispensers. However, Bottom-Loading water dispensers employ significantly more water contact components than Top-Loading water dispensers and, therefore, are more difficult to sanitize effectively. Ebac Limited introduced a Bottom-Loading water dispenser under the trademark EASYLOADER with a removable WATERTRAIL in an effort to make sanitization easier. However, this water dispenser was expensive to produce and has not succeeded commercially. 
     Therefore, there is a significant need for a Bottom-Loading liquid dispenser that can be readily and easily sanitized while also being relatively inexpensive to manufacture. There is also a significant need for a simplified removable liquid transport assembly that conveys liquid between a liquid storage container, one or more reservoirs and a dispensing nozzle or nozzles of the liquid dispenser that can be manufactured at a relatively low cost and can be readily removed and replaced to ensure effective sanitization of the liquid dispenser. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a novel and unobvious apparatus for dispensing liquid from a liquid storage container. 
     Another object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser that is relatively inexpensive to produce and is also easy to sanitize in a very short period of time. 
     Still another object of a preferred embodiment of the present invention is to provide a removable liquid transport assembly that is relatively inexpensive to manufacture while allowing for effective sanitization of the water dispenser. 
     A further object of a preferred embodiment of the present invention is to provide a removable liquid transport assembly configured to reduce the number of components thereof including the number of flexible hoses or conduits associated therewith. 
     Yet another object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser that requires only a single pump to pump water from a liquid storage container to one or more dispensing nozzles of a water dispenser. 
     Still a further object of a preferred embodiment of the present invention is to provide a removable liquid manifold that is substantially rigid with minimal flexible hosing associated therewith to expedite removal and replacement. 
     Yet still another object of a preferred embodiment of the present invention is to provide a removable liquid transport assembly configured to permit removal of a reservoir, reservoir dip tube, pump head, non-return valve, pressure relief valve, riser tube, pinch tube and dispenser nozzle upon removal of a liquid manifold, i.e., the step of removing the liquid manifold simultaneously effectuates the removal of all of the other aforementioned components of the removable liquid transport assembly. 
     Still yet a further object of a preferred embodiment of the present invention is to provide a removable liquid transport assembly with a liquid storage container dip tube that can be readily separated from the other components of the removable liquid transport assembly to facilitate removal thereof. 
     Another object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser that employs a self-priming pump with a pump head and drive motor where the pump head can be readily disconnected and securely connected to the drive motor to permit the removal and replacement of the pump head. 
     A further object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser that allows water in a reservoir to flow back into a liquid storage container in the event that an operating condition occurs which causes the volume of liquid to rise beyond a predetermined maximum value (e.g., a portion of the liquid in the chilled reservoir should freeze) to prevent damage to one or more components of the water dispenser while preventing liquid in the reservoir from flowing back into the liquid storage container when the volume of liquid does not exceed the predetermined maximum value. 
     Still a further object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser with a non-return valve that is designed to minimize the pressure drop across the non-return valve to reduce the size of the pump and ensure that the non-return valve has little to no effect on the flow of liquid from the liquid storage container to the reservoir. 
     Yet still a further object of a preferred embodiment of the present invention is to provide a Bottom-Loading water dispenser that allows water in a reservoir to flow back into a liquid storage container without passing through the pump or pump head in the event that an operating condition occurs which causes the volume of liquid to rise beyond a predetermined maximum value (e.g., a portion of the liquid in the chilled reservoir should freeze) to prevent damage to one or more components of the water dispenser while preventing liquid in the reservoir from flowing back into the liquid storage container when the volume of liquid does not exceed the predetermined maximum value. 
     It must be understood that no one embodiment of the present invention need include all of the aforementioned objects of the present invention. Rather, a given embodiment may include one or none of the aforementioned objects. Accordingly, these objects are not to be used to limit the scope of the claims of the present invention. 
     In summary, one preferred embodiment of the present invention is directed to an apparatus dispensing a liquid from a liquid storage container operably associated with the apparatus for dispensing a liquid. The apparatus includes a main housing having a dispensing location at which liquid from a liquid storage container is dispensed and a storage location for storing the liquid storage container. The dispensing location is disposed above at least a portion of the storage location. A reservoir is disposed in the housing. The reservoir is configured to receive a liquid from the liquid storage container prior to the liquid being dispensed from the main housing. A removable manifold is operably connected to the reservoir and the liquid storage container for conveying liquid between the reservoir and the liquid storage container. The removable manifold is further operably connected to the dispensing location to convey a liquid from the reservoir towards the dispensing location. The removable manifold has an upper chamber and a lower chamber. The upper chamber and the lower chamber share a common wall portion. The upper chamber is configured to direct a liquid from the reservoir towards the dispensing location in a substantially horizontal path. The lower chamber is configured to convey liquid between the liquid storage container and the reservoir in a substantially horizontal path. The upper chamber is disposed above the lower chamber. 
     Another preferred embodiment of the present invention is directed to an apparatus for dispensing a liquid from a liquid storage container operably associated with the apparatus for dispensing a liquid. The apparatus includes a main housing having a dispensing location at which liquid from a liquid storage container is dispensed and a storage location for storing a liquid storage container. The dispensing location is disposed above at least a portion of the storage location. A reservoir is disposed in the housing. The reservoir is configured to receive a liquid from the liquid storage container prior to the liquid being dispensed from the main housing. A valve assembly is disposed in a liquid flow path between the liquid storage container and the reservoir. The valve assembly includes a non-return valve and a pressure relief valve. The valve assembly further includes a valve housing for housing the non-return valve and the pressure relief valve. The valve assembly is configured such that when a volume of liquid upstream of the valve assembly exceeds maximum capacity, liquid upstream of the valve assembly can return to the liquid storage container. The valve assembly further is configured such that the non-return valve prevents liquid from flowing from the reservoir to the liquid storage container provided that the maximum capacity has not been exceeded. 
     A further preferred embodiment of the present invention is directed to an apparatus for dispensing a liquid from a liquid storage container operably associated with the apparatus for dispensing a liquid. The apparatus includes a main housing having a dispensing location at which liquid from a liquid storage container is dispensed and a storage location for storing a liquid storage container. The dispensing location is disposed above at least a portion of the storage location. A reservoir is disposed in the housing. The reservoir is configured to receive a liquid from the storage container prior to the liquid being dispensed from the main housing. A valve assembly is disposed in a liquid flow path between the liquid storage container and the reservoir. The valve assembly includes a non-return valve for preventing liquid from the reservoir to flow back into the liquid storage container. The non-return valve includes means for minimizing pressure drop across the non-return valve to minimize the effect the non-return valve has on liquid flow from the liquid storage container to the reservoir. 
     Still another preferred embodiment of the present invention is directed to an apparatus for dispensing a liquid from a liquid storage container operably associated with the apparatus for dispensing a liquid. The apparatus includes a main housing having a dispensing location at which liquid from a liquid storage container is dispensed and a storage location for storing a liquid storage container. The dispensing location is disposed above at least a portion of the storage location. A reservoir is disposed in the housing. The reservoir is configured to receive a liquid from the liquid storage container prior to the liquid being dispensed from the main housing. A self-priming pump has a pump head detachably connected to a drive motor. The self-priming pump is configured to pump liquid from the liquid storage container to the reservoir. The pump head is disposed in a removable manifold to allow the pump head to be readily replaced. The pump includes a drive pin and a drive crank. At least one of the drive crank and the drive pin includes means for facilitating mating of the pump head and the drive motor. 
     Still a further preferred embodiment of the present invention is directed to an apparatus for dispensing a liquid from a liquid storage container operably associated with the apparatus for dispensing a liquid. The apparatus includes a main housing having a dispensing location at which liquid from a liquid storage container is dispensed and a storage location for storing a liquid storage container. The dispensing location is disposed above at least a portion of the liquid storage location. The apparatus further includes a removable liquid transport assembly including a substantially rigid liquid manifold, a valve assembly, a reservoir and a pump head. The removable liquid transport assembly being configured such that the substantially rigid liquid manifold, the valve assembly, the reservoir and the pump head are removable from the main housing as a single unit. The substantially rigid liquid manifold having a liquid flow channel through which liquid traveling between the liquid storage container and the reservoir passes. At least a portion of the pump head is disposed in the liquid flow channel of the substantially rigid manifold. At least a portion of the valve assembly is disposed in the liquid flow channel of the substantially rigid liquid manifold. The liquid flow channel is configured to connect the valve assembly to the pump head without using any flexible tubing. The reservoir is connected to the liquid flow channel of the substantially rigid manifold. The valve assembly includes at least one of a pressure relief valve and a non-return valve. 
     Another preferred embodiment of the present invention is directed to a liquid transport assembly for a liquid dispenser to convey a liquid between a liquid storage container and a dispensing location of the liquid dispenser. The liquid transport assembly includes a removable liquid transport assembly configured to be readily installed in and removed from a liquid dispenser to permit the liquid dispenser to be readily sanitized. The removable liquid transport assembly includes a substantially rigid liquid manifold, a valve assembly, a reservoir and a pump head. The removable liquid transport assembly is configured such that the substantially rigid liquid manifold, the valve assembly, the reservoir and the pump head are removable from the liquid dispenser as a single unit. The substantially rigid liquid manifold has a liquid flow channel through which liquid travel passes during operation of the liquid dispenser. At least a portion of the pump head is disposed in the liquid flow channel of the substantially rigid manifold. At least a portion of the valve assembly is disposed in the liquid flow channel of the substantially rigid liquid manifold. The liquid flow channel is configured to connect the valve assembly to the pump head without using any flexible tubing. The reservoir is connected to the liquid flow channel of the substantially rigid manifold. The valve assembly includes at least one of a pressure relief valve and a non-return valve. 
     A further preferred embodiment of the present invention is directed to a liquid transport assembly for a liquid dispenser to convey a liquid between a liquid storage container and a dispensing location of the liquid dispenser. The liquid transport assembly includes a removable liquid transport assembly configured to be readily installed in and removed from a liquid dispenser to permit the liquid dispenser to be readily sanitized. The removable liquid transport assembly includes a liquid manifold, a valve assembly, a reservoir and a pump head. The removable liquid transport assembly is configured such that the liquid manifold, the valve assembly, the reservoir and the pump head are removable from the liquid dispenser as a single unit. The valve assembly includes at least a pressure relief valve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of a water dispenser formed in accordance with a preferred embodiment of the present invention with the liquid transport assembly removed therefrom. 
         FIG. 2  is a view similar to that depicted in  FIG. 1  with the liquid transport assembly formed in accordance with a preferred embodiment of the present invention installed in the water dispenser. 
         FIG. 3  is a front elevation view of a water dispenser formed in accordance with a preferred embodiment of the present invention with the water bottle and portions of the main housing removed. 
         FIG. 4  is fragmentary perspective view of a water dispenser formed in accordance with a preferred embodiment of the present invention. 
         FIG. 5  is a fragmentary perspective view similar to that depicted in  FIG. 4  but from a slightly different vantage point to reveal components not readily seen in  FIG. 4 . 
         FIG. 6  is a fragmentary perspective view of a water dispenser formed in accordance with a preferred embodiment of the present invention with various aspects shown in phantom to permit viewing of other components. 
         FIG. 7  is a cross-sectional view of a liquid transport assembly formed in accordance with a preferred embodiment of the present invention. 
         FIG. 8  is a fragmentary cross-sectional view of a liquid transport assembly formed in accordance with a preferred embodiment of the present invention. 
         FIG. 9  is a fragmentary perspective view of a liquid transport assembly formed in accordance with a preferred embodiment of the present invention with various aspects shown in phantom to permit viewing of other components. 
         FIG. 9A  is a perspective view of a portion of the liquid transport assembly formed in accordance with a preferred embodiment of the present invention. 
         FIG. 9B  is a perspective view similar to  FIG. 9A  with portions removed to permit viewing of the internal cavity of a liquid manifold formed in accordance with a preferred embodiment of the present invention. 
         FIG. 9C  is a perspective view similar to  FIG. 9B  with the cover plate for one of the lower chambers removed to permit viewing of the internal cavity of the particular lower chamber. 
         FIG. 10  is cross-sectional view of a preferred form of valve assembly. 
         FIG. 11  is a cross-sectional view of a preferred form of self-priming pump for a preferred embodiment of the present invention with the drive motor shown detached from the pump head. 
         FIG. 12  is a cross-sectional view of a preferred form of self-priming pump for a preferred embodiment of the present invention with the drive motor shown connected to the pump head. 
         FIG. 13  is a perspective view of a preferred form of drive motor. 
         FIG. 14  is a perspective view of a portion of a liquid transport assembly formed in accordance with an alternative embodiment of the present invention with the reservoir shown in phantom to permit viewing of the reservoir dip tube. 
         FIG. 15  is a perspective view of the portion of a liquid transport assembly illustrated in  FIG. 14  taken from a different angle. 
         FIG. 16  is a perspective view of the portion of a liquid transport assembly illustrated in  FIG. 14  as seen from the bottom. 
         FIG. 17  is a perspective view similar to  FIG. 14  with portions removed to permit viewing of the internal cavity of a liquid manifold. 
         FIG. 18  is an enlarged perspective view similar to  FIG. 17  with portions removed to permit viewing of the internal cavity of a liquid manifold. 
         FIG. 19  is a fragmentary cross-sectional view of the liquid transport assembly illustrated in  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION 
     The preferred forms of the invention will now be described with reference to  FIGS. 1-19 . The appended claims are not limited to the preferred form and no term and/or phrase used herein is to be given a meaning other than its ordinary meaning unless it is expressly stated otherwise. 
     FIGS.  1  THROUGH  13   
     Referring to  FIGS. 1 to 13 , a liquid dispenser A employing a preferred form of the invention is illustrated in one of many possible configurations. In the most preferred form, liquid dispenser A dispenses chilled and hot water for human consumption. However, the present invention is not limited to a liquid dispenser that dispenses chilled and hot water for human consumption. Rather, the liquid dispenser may dispense other liquids including but not limited to ambient temperature drinking water and carbonated liquids. Liquid dispenser A includes a main housing B having a substantially hollow internal cavity for housing components of the liquid dispenser, a liquid dispensing location C and a liquid storage location D for receiving and storing a liquid storage container E in an upright orientation. Liquid dispenser A further includes a cover F pivotally connected to main housing B. Any suitable latch mechanism may be used to permit the forward edge of the cover F to be secured to and released from a corresponding front edge of main housing B. Referring to  FIGS. 1 and 2 , a cup G is shown in the liquid dispensing location C. The liquid storage container E is preferably a conventional five (5) gallon water bottle oriented in an upright manner. 
     Referring to  FIGS. 1 and 2 , a reservoir housing  2 , a cooling system  3 , a pump motor  4  and a riser tube guide member  6  are disposed in the internal cavity of liquid dispenser A. Liquid dispenser A includes a removable liquid transport assembly H as seen, for example, in  FIGS. 2 and 6 through 9 . The removable liquid transport assembly H includes a substantially rigid conduit housing  8  removably connected to a substantially rigid liquid manifold  10  as seen for example in  FIGS. 4 and 5 . Conduit housing  8  and manifold  10  may be formed out of any suitable material including plastic. Any suitable fasteners may be used to removably secure conduit housing  8  to liquid manifold  10 . Further, it will be readily appreciated that conduit housing  8  may be permanently fixed to liquid manifold  10  or may be formed as one piece with liquid manifold  10 . 
     Conduit housing  8  preferably houses a pinch tube  12  and a dispensing nozzle  14 . In the most preferred form, as seen in  FIG. 9A , the pinch tube  12  and the dispensing nozzle  14  are formed from a single piece of silicon rubber. However, the pinch tube  12  and the dispensing nozzle  14  could be formed from separate pieces that are connected in a fluid tight manner. Referring to  FIGS. 8, 9B and 9C , liquid manifold  10  includes lower chambers  16  and  17 , an upper chamber  18  and a small vent hole  20 . Liquid manifold  10  further includes an internally threaded collar  22  and a secondary dispensing port  24 . Referring to  FIGS. 9B and 9C , lower chamber  16  is smaller than lower chamber  17 . A cover plate  19  separates lower chamber  16  and lower chamber  17 . Opening  21  formed in cover plate  19  allows liquid to pass from lower chamber  16  to lower chamber  17 . Referring to  FIGS. 9A and 9B , lower chamber  17  and upper chamber  18  share wall portion  23 . Referring to  FIGS. 9 and 9B , for example, wall portion  23  includes a lower section/segment  23   a  that extends downwardly into reservoir  26 . Further, wall portion  23  forms the lowermost portion of upper chamber  18 . 
     The removable liquid transport assembly H further includes a reservoir  26  having a neck portion with external threads corresponding to the internal threads of collar  22  so that the reservoir  26  can be readily connected to liquid manifold  10 . It will be readily appreciated that reservoir  26  may be connected to liquid manifold  10  in numerous other ways. The removable liquid transport assembly H further includes a reservoir dip tube  28 , a pump head  30 , a valve assembly  32 , a riser tube  34  and a liquid storage container dip tube  36  having a connecting member  38  for removably connecting the liquid storage container dip tube  36  to the lower end  40  of riser tube  34 . As clearly seen in  FIG. 9 , lower section/segment  23   a  of wall portion  23  receives an upper end of reservoir dip tube  28 . As shown in  FIG. 7 , the liquid storage container dip tube  36  extends into liquid storage container E through cap  42  of container E. 
     The secondary dispensing port  24  may be connected to a hot water supply assembly I including a hot water reservoir (not shown), a hot water reservoir dip tube (not shown), a heating element (not shown), one or more conduits (not shown) for conveying hot water from the hot water reservoir to a second dispensing nozzle (not shown). The hot water supply assembly I can be omitted. Where the hot water supply assembly I is omitted, the secondary dispensing port  24  may be plugged to prevent the flow of water through port  24 . Alternatively, the secondary dispensing port  24  may be operably connected to a second dispensing nozzle in a well-known manner to dispense water at ambient temperature through the second dispensing nozzle when lever  44  is depressed. Alternatively, the secondary dispensing port  24  can be connected to a carbonated liquid source to dispense a carbonated liquid from the second dispensing nozzle. 
     Cold water tap lever  46  controls the flow of chilled water from reservoir  26  through dispensing nozzle  14 . Referring to  FIG. 4 , a pinch valve  48  is operably associated with cold water tap lever  46  to control the flow of chilled water out dispensing nozzle  14 . Specifically, pinch valve  48  acts on pinch tube  12  in a well-known manner to prevent the flow of chilled water out dispensing nozzle  14  until such time as lever  46  is depressed. Spring  49  biases lever  46  upwardly causing pinch valve  48  to close off pinch tube  12 . Once the biasing force of spring  49  is overcome by a person depressing lever  46 , a micro switch  51  activates self-priming pump J to pump water from container E upwardly through dip tube  36  and riser tube  34  into lower chamber  16  of liquid manifold  10 . The liquid travels through valve assembly  32  and pump head  30  and passes into lower chamber  17  through opening  21 . Liquid flowing through chamber  17  empties into reservoir  26  (which chills the water stored therein) which in turn causes chilled water stored in reservoir  26  to pass upwardly through dip tube  28  into upper chamber  18  and out dispensing nozzle  14 . The flow of liquid when lever  46  is depressed is shown by the arrows in  FIG. 8 . 
     Pinch valve  50  is operably associated with lever  44  to act in a similar manner to permit and prevent liquid to flow out a second dispensing nozzle (not shown). In the most preferred form, the liquid dispensed from the second dispensing nozzle is hot water. When lever  44  is depressed, pump J pumps liquid from container E through dip tube  36  and riser tube  34  into lower chamber  16  of liquid manifold  10  and out secondary dispensing port  24  into a hot water reservoir which in turn causes the hot water stored in the water heating reservoir to flow through a dip tube into one or more conduits connecting the hot water reservoir to the second dispensing nozzle (not shown) and ultimately out the second dispensing nozzle (not shown). 
     Referring to  FIGS. 8 and 10 , the valve assembly  32  will be described in greater detail. Valve assembly  32  includes a valve housing  52  having a lower valve housing member  54  and an upper valve housing member  56 . Preferably, a non-return valve  58  and a pressure relief valve  60  are disposed in housing  52 . Non-return valve  58  includes a spring  62 , a spring follower  64 , a diaphragm  66  and a sealing ring  68 . In the closed position, diaphragm  66  seats on annular seat  67  of sealing ring  68  as illustrated in  FIG. 10 . When lever  46  is depressed, pump J sucks liquid upwardly causing the liquid to pass through dip tube  36 , through the riser tube  34  and through openings  70  in lower valve housing member  54 . When the force of the liquid is sufficient to overcome the force of spring  62 , diaphragm  66  moves upwardly off the annular seat  67  of sealing ring  68  which in turn causes the liquid to pass through flow hole  72  formed in diaphragm  66  out openings  74  in upper valve housing member  56 . The liquid in turn passes through pump head  30  and enters reservoir  26  forcing chilled water stored in reservoir  26  to ultimately pass out through dispensing nozzle  46  as previously described. When lever  46  is released, the pump deactivates ceasing the flow of liquid from container E which allows spring  62  to reseat diaphragm  66  on annular seat  67  of sealing ring  68  as shown in  FIG. 10 . When the sealing valve assembly  52  is in the position illustrated in  FIG. 10 , liquid in reservoir  26  cannot flow back into container E. 
     The non-return valve  58  is designed to minimize the pressure drop across the non-return valve to prevent the non-return valve from adversely affecting the flow of liquid from container E to reservoir  26 . By designing the valve  58  to have minimal effect on the flow of liquid, the preferred embodiment can minimize the size of the pump. The pressure drop is minimized by the fact that to open the valve  58  flow in the forward direction must pull against the full area of the diaphragm  66  while to close the valve  58  spring  62  need only overcome the annular seat  67  of sealing ring  68 . As is readily evident from  FIG. 10 , the outer diameter of the diaphragm  66  is significantly greater than the diameter of the annular seat  67  of sealing ring  68 . In a most preferred form, the outer diameter of the diaphragm  66  is approximately 32 mm while the diameter of the annular seat  67  of the sealing ring  68  is approximately 8 mm. This relationship provides an advantageous pressure ratio of 16:1. 
     Vent hole  20  allows air to escape through dispensing nozzle  46 . When the supply of liquid in container E is exhausted, a small amount of air will be pumped through the liquid transport assembly and vented through vent hole  20  effectively stopping the liquid dispenser A from dispensing liquid until the exhausted container E is replaced. 
     The pressure relief valve  60  includes a sealing element  76 , a spring  78  and vent hole  80  formed in sealing ring  68 . Should the volume of the liquid upstream of valve assembly  52  increase beyond a predetermined maximum volume, the upstream liquid will exert a downward force on sealing element  76  which in turn opens vent hole  80  allowing upstream liquid to return to container E. Once a sufficient amount of upstream liquid has returned to container E, the force of spring  78  will return sealing element  76  to the closed position preventing any additional upstream liquid from flowing back into container E. It should be noted that when liquid flows upwardly from container E in route to reservoir  26  the liquid does not pass through pressure relief valve  60  as the sealing element  76  is in the position shown in  FIG. 10  to close off the vent hole  80 . One condition that could cause pressure relief valve  60  to open is where a portion of the liquid in reservoir  26  freezes causing an increase in the effective volume of the liquid upstream of valve assembly  52 . Without pressure relief valve  60 , one or more components of the liquid dispenser A could be irreparably damaged. 
     As seen in  FIGS. 8, 9B and 9C , valve assembly  52  extends into lower chamber  16  of liquid manifold  10  and is secured thereto such that the valve assembly moves with liquid manifold  10 . 
     The self-priming pump J will now be described in greater detail with reference being made to  FIGS. 11 to 13 . In the most preferred form, self-priming pump J is a three cylinder swash-plate diaphragm pump having a drive motor  4  and a pump head  30 . The pump head  30  can be readily disconnected from the drive motor  4  by merely moving the pump head  30  upwardly from the engaged position shown in  FIG. 12  to the disengaged position shown in  FIG. 11 . Drive motor  4  includes a drive crank  82  that rotates upon activation of drive motor  4  by micro switch  51 . The drive crank  82  preferably includes a sloping surface  84  that drive pin  86  of pump head  30  strikes when the pump head  30  is connected to the drive motor  4 . The sloping surface  84  facilitates the mating of drive motor  4  and pump head  30  by guiding the drive pin  86  into the angled socket  88  thereby orienting swash plate  90  at the desired angle. Swash plate  90  is connected to piston  92  that moves in cylinder  94  formed in pump head  30 . Pump head  30  further includes an inlet valve  96 , an inlet chamber  98 , an outlet valve  100  and an outlet chamber  102 . As is readily seen in  FIG. 8 , pump head  30  extends into lower chamber  16  of liquid manifold  10  and secured thereto such that the pump head  30  moves with liquid manifold  10 . 
     To readily replace the bulk of the liquid transport assembly H, one need only raise lid F, raise latch  104  to the position shown in  FIGS. 3, 5 and 6  to free conduit housing  8 , turn rotating clamps  105  and  107  to the positions shown in  FIG. 5  to free manifold  10 , disconnect riser tube  34  from dip tube  36  and raise liquid manifold  10  upwardly which in turn causes all of the elements of the liquid transport assembly shown in  FIGS. 8 and 9  connected to liquid manifold  10  to move upwardly with liquid manifold  10 . Hence, the portions of the liquid transport assembly H illustrated in  FIGS. 8 and 9  can be readily removed and replaced as a unit. Once removed the portion of the liquid transport assembly H shown in  FIGS. 8 and 9  can be replaced with a new, sanitized assembly having the same components as the removed portion of the liquid transport assembly H. Guide member  6  having a hollow cavity generally conforming to the shape of riser tube  34  and having slightly larger dimensions facilitates insertion of the sanitized riser tube  34 . Once separated from riser tube  34 , dip tube  36  can easily and readily be removed and replaced with a sanitized dip tube. 
     FIGS.  14  THROUGH  19   
     Referring to  FIGS. 14 through 19 , an alternate form of removable liquid transport assembly K will now be described that can be used with liquid dispenser A in place of liquid transport assembly H. Removable liquid transport assembly K is similar to removable liquid transport assembly H and, therefore, only the differences will be described in detail. The use of the same reference numerals to describe components of assemblies H and K indicates the assemblies have the same component. The removable liquid transport assembly K includes a substantially rigid conduit housing  8  removably connected to a substantially rigid liquid manifold  10  as seen for example in  FIG. 14 . Conduit housing  8  and manifold  10  may be formed out of any suitable material including plastic. Any suitable fasteners may be used to removably secure conduit housing  8  to liquid manifold  10 . Further, it will be readily appreciated that conduit housing  8  may be permanently fixed to liquid manifold  10  or may be formed as one piece with liquid manifold  10 . 
     Conduit housing  8  preferably houses a pinch tube  12  and a dispensing nozzle  14 . In the most preferred form, as seen in  FIG. 14 , the pinch tube  12  and the dispensing nozzle  14  are formed from a single piece of silicon rubber. However, the pinch tube  12  and the dispensing nozzle  14  could be formed from separate pieces that are connected in a fluid tight manner. Referring to  FIGS. 14 and 18 , liquid manifold  10  includes lower chambers  16  and  17  and an upper chamber  18 . Liquid manifold  10  further includes an internally threaded collar  22  and a secondary dispensing port  24 . Referring to  FIG. 18 , lower chamber  16  is smaller than lower chamber  17 . As seen in  FIG. 18 , a cover plate  109  separates lower chamber  16  and lower chamber  17 . Openings  110  and  112  formed in cover plate  109  allow liquid to pass from lower chamber  16  to lower chamber  17 . Referring to  FIG. 17 , lower chamber  17  and upper chamber  18  share a wall portion  23  which forms the lowermost portion of upper chamber  18 . 
     The removable liquid transport assembly K further includes a reservoir  26  having a neck portion with external threads corresponding to the internal threads of collar  22  so that the reservoir  26  can be readily connected to liquid manifold  10 . It will be readily appreciated that reservoir  26  may be connected to liquid manifold  10  in numerous other ways. The removable liquid transport assembly K further includes a reservoir dip tube  28 , a pump head  30  and a valve assembly  108 . A riser tube and a liquid storage container dip tube having a connecting member as described in connection with liquid transport assembly H may be used to connect the valve assembly  108  to a liquid storage container similar to liquid storage container E. 
     The secondary dispensing port  24  may be connected to a hot water supply assembly including a hot water reservoir, a hot water reservoir dip tube, a heating element, one or more conduits for conveying hot water from a hot water reservoir to a second dispensing nozzle. The hot water supply assembly can be omitted. Where the hot water supply assembly is omitted, the secondary dispensing port  24  may be plugged to prevent the flow of water through port  24 . Alternatively, the secondary dispensing port  24  may be operably connected to a second dispensing nozzle in a well-known manner to dispense water at ambient temperature through the second dispensing nozzle. Alternatively, the secondary dispensing port  24  can be connected to a carbonated liquid source to dispense a carbonated liquid from the second dispensing nozzle. 
     The flow of cold water from reservoir  26  through dispensing nozzle  14  can be controlled with the components described in connection with liquid transport assembly H. 
     Referring to  FIGS. 18 and 19 , the valve assembly  108  will be described in greater detail. Valve assembly  108  includes valve housing having a lower valve housing member  116  and an upper valve housing member  120 . A plurality of openings  122  are formed in upper valve housing  120  as shown in  FIG. 18 . Referring to  FIGS. 16 and 18 , a conduit  123  connects the riser tube (not shown) to the chamber  125  formed by lower valve housing member  116  so that liquid from the liquid storage container may pass from the riser tube into chamber  125 . Preferably, a non-return valve  124  and a pressure relief valve  126  are disposed in the valve housing. Non-return valve  124  includes a spring  128 , a spring follower  130 , a diaphragm  132  and a sealing ring  134 . In the closed position, diaphragm  132  seats on sealing ring  134  as illustrated in  FIG. 19 . When a lever like lever  46  is depressed, a pump similar to pump J sucks liquid upwardly causing the liquid to pass through the dip tube, through the riser tube and through conduit  123  into chamber  125 . When the force of the liquid is sufficient to overcome the force of spring  128 , diaphragm  132  moves upwardly off the sealing ring  134  which in turn causes the liquid to pass through flow hole  136  formed in diaphragm  132  out openings  122  in upper valve housing member  120 . The liquid in turn passes through a plurality of openings  138  into pump head  30 . Openings  138  communicate with passageway  140  allowing liquid to pass through passageway  140  of pump head  30  and out opening  110 . The liquid then enters reservoir  26  through openings  142  forcing chilled water stored in reservoir  26  to ultimately pass upwardly through reservoir tube  28 , through chamber  18 , through tube  12  and through nozzle  14 . When the lever is released, the pump deactivates ceasing the flow of liquid from the container which allows spring  128  to reseat diaphragm  132  on sealing ring  134  as shown in  FIG. 19 . When the sealing valve assembly  108  is in the position illustrated in  FIG. 19 , liquid in reservoir  26  cannot flow back through pump head  30  into chamber  125 . 
     The non-return valve  124  is designed similar to non-return valve  58  to minimize the pressure drop across the non-return valve to prevent the non-return valve from adversely affecting the flow of liquid from the container to reservoir  26 . 
     The pressure relief valve  126  includes a sealing element  144  and a spring  146 . When in the position shown in  FIG. 19 , sealing element  144  seals the lower end of vertically extending passageway  148  formed in sealing ring  134 . Should the volume of the liquid upstream of valve assembly  108  increase beyond a predetermined maximum volume, the upstream liquid will exert a downward force on sealing element  144  which in turn opens the lower end of passageway  148  allowing upstream liquid to pass downwardly though opening  112  formed in plate  109  into annular conduit  149  preferably formed as one piece with plate  109 . The liquid then passes through passageway  148 , through openings  150 , through chamber  125  and through conduit  123  in route to the liquid storage container. Once a sufficient amount of upstream liquid has returned to the container, the force of spring  146  will return sealing element  144  to the closed position preventing any additional upstream liquid from flowing back into the container. It should be noted that when liquid flows upwardly from container E in route to reservoir  26  the liquid does not pass through pressure relief valve  126  as the sealing element  144  is in the position shown in  FIG. 19  to close off passageway  148 . Sealing ring  134  includes openings similar to the openings in sealing ring  68  shown in  FIG. 10  to allow liquid to flow from lower chamber  125  through opening  136  formed in diaphragm  132 . One condition that could cause pressure relief valve to open is where a portion of the liquid in reservoir  26  freezes causing an increase in the effective volume of the liquid upstream of valve assembly  108 . Without the pressure relief valve, one or more components of the liquid dispenser could be irreparably damaged. As is readily appreciated from the above description, when one or more conditions exist which cause sealing element  144  to overcome the force of spring  146 , upstream liquid flows back into the container through valve assembly  108  without passing through pump head  30 . In fact, liquid cannot flow from pump head  30  to chamber  125 . 
     As seen in  FIG. 18 , valve assembly  108  extends into lower chamber  16  of liquid manifold  10  and is secured thereto such that the valve assembly moves with liquid manifold  10 . 
     A self-priming pump similar to self-priming pump J can be operably connected to pump head  30 . The liquid transport assembly K can be readily replaced in a manner similar to liquid transport assembly H. 
     While this invention has been described as having a preferred design, it is understood that the preferred design can be further modified or adapted following in general the principles of the invention and including but not limited to such departures from the present invention as come within the known or customary practice in the art to which the invention pertains. The claims are not limited to the preferred embodiment and have been written to preclude such a narrow construction using the principles of claim differentiation.