Abstract:
An energy efficient water cooler assembly and/or liquid dispensing apparatus and method for using same, including an energy-saving baffle, which may take the form of a conventional or bottom load water cooler, and which may be either gravity-driven or pump-fed.

Description:
PATENT INCORPORATED BY REFERENCE 
       [0001]    Commonly-assigned U.S. Pat. No. 8,356,731, titled “Energy Saving Baffle For Water Cooler,” issued Jan. 22, 2013, is incorporated by reference in its entirety into this disclosure, including but not limited to the energy saving baffle disclosure of FIGS. 27-29 and the corresponding text relating to those drawings (14:13-15:32). 
       BACKGROUND OF THE INVENTION 
       [0002]    The present invention generally relates to water cooler assemblies and liquid dispensing apparatus. More specifically, the invention relates to an energy saving hot water tank used in such assemblies and apparatus. 
         [0003]    Using a water cooler assembly with a cold tank on top and a hot tank beneath it has been known for decades. Energy consumption for such past water cooler assemblies has been in the range of about 2 kilowatt-hours/day. EPA regulations effective Jan. 22, 2010 require energy consumption of less than about 1.2 kW-h/day to properly label a product as “Energy Star.” The EPA guidelines can be met by taking steps such as using heavy insulation (such as vacuum-insulated walls for the hot tank) and rerouting water from the bottom of the hot tank. 
         [0004]    Energy consumption tests conducted by the present inventors and separately analyzing the cold system, and the hot system, showed that energy consumed by the separate systems was substantially less than the combined system, allowing the present inventors to conclude that the cold/hot system interaction has a substantial impact on energy consumption, perhaps as much as 30%. 
         [0005]    The present inventors also found that placing a restrictor in the baffle within the pathway between the cold and hot tanks, as disclosed in commonly-assigned U.S. Pat. No. 8,356,731, reduced energy loss to about 1.1 kWh/day). The present inventors also found that using pump-fed rather than gravity systems further reduced energy consumption to about 0.7-0.8 kW-h/day. Pump-fed systems use longer tubing in between the hot and cold tanks, allowing water in this tubing, during an idle stage, to more closely equalize in temperature before it travels to an the adjacent tank, requiring less frequent running of the cold and hot systems, and correspondingly lower energy consumption. 
         [0006]    It would be advantageous to design a water cooler assembly and water dispensing apparatus that is more energy efficient than those currently available for gravity-fed systems, and comparable in energy efficiency to pump-fed systems. 
       SUMMARY OF THE INVENTION 
       [0007]    The objects mentioned above, as well as other objects, are solved by the present invention, which overcomes disadvantages of prior water cooler assemblies and liquid dispensing apparatus, while providing new advantages not believed associated with such assemblies and apparatus. 
         [0008]    In a preferred embodiment of the invention, a liquid dispensing apparatus is provided, including cold and hot tanks in liquid communication with each other and with a dispensing faucet. A baffle is housed within the cold tank, and separates liquid within the cold tank into two or more regions having differing temperatures. A baffle tube allows liquid within the cold tank adjacent the baffle to move between the cold and hot tanks. Preferably, the baffle tube houses a restrictor, such as a floating restrictor (e.g., a hollow ball) with a specific density less than the specific density of the liquid. In this embodiment, the restrictor normally floats upward within the baffle tube to partially seal against an upper retaining member within the baffle tube and thereby restrict liquid circulation between the hot and cold tanks. Preferably, a non-metal gasket, such as a silicone gasket, forms a thermal barrier between liquid within the baffle tube, the cold tank, and an intake portion of the hot tank. 
         [0009]    In a particularly preferred embodiment, the hot tank is located below the cold tank, and following liquid discharge from the hot tank, the restrictor is pushed downwardly within the baffle tube, to a lowermost position below a bottom edge of the cold tank, by liquid flowing from the cold tank to replenish the hot tank. The floating restrictor, when at its lowermost range below the bottom edge of the cold tank, may be contained by a non-metal compartment. 
         [0010]    The invention may be used with either gravity-driven dispensing systems (e.g., a traditional water cooler using an inverted water bottle), or pump-fed dispensing systems. 
         [0011]    In an alternative embodiment, a liquid dispensing apparatus is provided with cold and hot tanks in liquid communication with each other and with a dispensing faucet, and a baffle housed within the cold tank, which separates two or more regions of liquid in the cold tank having differing temperatures. A baffle tube may be used to allow liquid within the cold tank adjacent the baffle to move between the cold and hot tanks. The baffle tube may house a floating restrictor with a specific density less than the specific density of the liquid. The restrictor may normally float upward within the baffle tube to partially seal against an upper retaining member within the baffle tube and thereby restrict liquid circulation between the hot and cold tanks. Preferably, the hot tank is located below the cold tank. Following liquid discharge from the hot tank, the restrictor is pushed downwardly within the baffle tube, to a lowermost position below a bottom edge of the cold tank, by liquid flowing from the cold tank to replenish the hot tank. In this alternative embodiment, the baffle tube may include a baffle stem portion, which may have an inner diameter substantially greater than 10 mm, such as a about 14 mm. The baffle tube may also include a snap-on adaptor which press-fits into a baffle nut which fastens to an intake portion of the hot tank. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The novel features which are characteristic of the invention are set forth in the appended claims. The invention itself, however, together with further objects and attendant advantages thereof, can be better understood by reference to the following description taken in connection with the accompanying drawings, in which: 
           [0013]      FIG. 1  is a front and side perspective view of a bottom load water cooler of the prior art; 
           [0014]      FIG. 2  is a perspective view of a preferred embodiment of the invention; and 
           [0015]      FIG. 3  is an enlarged, sectional view of an alternative embodiment of the invention; and 
           [0016]      FIG. 4  is a partial perspective and cross-sectional view of the embodiment shown in  FIG. 3 . 
       
    
    
       [0017]    The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]    Set forth below is a description of what are believed to be the preferred embodiments and/or best examples of the invention claimed. Future and present alternatives and modifications to this preferred embodiment are contemplated. Any alternatives or modifications which make insubstantial changes in function, in purpose, in structure, or in result are intended to be covered by the claims of this patent. 
         [0019]    Referring first to  FIG. 1 , a bottom load water cooler assembly, generally referred to by reference numeral  10 , is shown. Water cooler assembly  10  includes an enclosure  604  with side panels  600 , side frames  602 , and rear top panel  601 , housing an inverted water bottle  15 , a cold tank  115  which may rest on bracket  710 , and as hot tank  117  located below the cold tank; the hot tank may rest on center shelf  607 . Compressor  606  may also rest on center shelf  607 . 
         [0020]    The water cooler assembly  10  shown in  FIG. 1  sources water using a pump fed system (not shown), either from water bottle  15  or from a pressurized source from a municipal or other water supply. Alternatively, a gravity-driven dispensing system may be used, using a water bottle located above the cold and hot tanks. 
         [0021]    Preferably, a restrictor (e.g., a floating ball) moving within a baffle system, as disclosed in U.S. Pat. No. 8,356,731, is used for energy efficiency purposes (i.e., to control convection losses in the pathway between the hot and cold tanks). Hot tank  117  should also be covered with insulation  118  ( FIG. 3 ), such as polyethylene foam, while cold tank  115  may be covered with insulation  315  such as styrofoam. 
         [0022]    Referring now to  FIG. 2 , spiral tubing  130  is preferably used between hot water tank  117  and cold water tank  115  for cold water flowing from the cold tank into the hot tank. Refrigerant tubing  215  ( FIG. 3 ) may be provided around the circumference of cold tank  115 , as is well known in the art. The longer water pathway distance provided by the spiral tubing enhances energy efficiency in the pathway between the hot and cold tanks, as mentioned above. An exemplary, uncoiled length for spiral tubing  130  of the present invention is between about 1-2 feet, and more preferably between about 15-16 inches. By using a spiral shape, the lengthened tubing can be made to fit into a tight space, as desired. 
         [0023]    Still referring to  FIG. 2 , both the inlet portion  130   a  of tubing  130  (water from the cold tank traveling into the hot tank), and the outlet portion  150   a  of tubing  150  (water from the hot tank traveling directly, and which may be connected by hot water outlet thread portion  151  to the faucet or dispensing nozzle) may be stainless steel which is welded directly on to the hot tank, and need not be detachable. 
         [0024]    Referring to both alternative embodiments shown in  FIGS. 2-3 , hot water intake thread portion  140  (which may be welded or otherwise connected to tubing  130 ) is preferably now made from plastic rather than metal (plastic is a much poorer conductor of heat or cold than metal), reducing the energy loss by preventing the hot tank metal portion from directly contacting cold water from cold tank  115  traveling through tubing  130 . In more detail, tubing  130  preferably includes an enlarged passageway  140  accommodating plastic hot tank intake thread piece  165  and a silicone gasket  167  to thermally separate direct contact between water from the cold tank and metal hot tank intake threaded piece  135 . As shown, because the lower portion of plastic hot tank intake thread piece  165  is in the hot water zone (cold tank Styrofoam insulation  315  is located below the cold tank, as shown in  FIG. 3 , and the area above the bottom of the cold tank is the zone separation point), if thread piece  165  were made of metal, it will more easily conduct heat up to the cold tank through the water in tubing  130 , causing energy losses. Conversely, because the upper portion of gasket  167  is in the cold water zone, if it were metal, once it is chilled in the cold water zone, it will conduct cold temperatures down to the hot tank more easily, causing thermal losses. 
         [0025]    Referring now to  FIG. 3 , a baffle  200 , similar to the baffle shown and described in FIGS. 27-29 of U.S. Pat. No. 8,356,731, and utilizing floating ball/restrictor  210 , movable within baffle tube  201 , may be located in cold tank  115 . (The ball or other restrictor normally floats upward within baffle tube  201  to partially seal against an upper retaining member within the baffle tube and thereby restrict liquid circulation between the hot and cold tanks; when a dispensing user discharges liquid from the hot tank, the ball may be pushed downwardly by liquid flowing from the cold tank to replenish the hot tank.) Baffle nut  228  may be used, and works like a screw nut to: (a) thread onto the end of intake thread portion  140  in the  FIG. 2  embodiment; or (b) thread onto the end of plastic hot tank intake thread portion  165  in the  FIG. 3  embodiment. In either case, this helps secure the cold tank in place, while also preventing vertical movement of baffle  200  during use. 
         [0026]    Referring to the  FIG. 3  embodiment, plastic hot tank intake thread piece  165 , in turn, may thread into metal hot water intake thread portion  135  (Which may be welded or otherwise attached to tubing  130 ); the interior portion of plastic thread piece  165  serves to contain the restrictor  210  at its lowest position. Gasket  167 , such as a silicone gasket, is preferably used and serves to thermally separate direct contact between plastic intake thread portion  165  and cold tank  115 . 
         [0027]    Referring now to  FIGS. 3-4 , in the preferred embodiment shown there, baffle stem portion  201  snaps on snap-on adaptor  169 , and adaptor  169  in turn press-fits into baffle nut  228 . Adaptor  169  enables an increase in the inner diameter of stem portion  201 , while fitting into baffle nut  228 , permitting an adequate flow rate. Using this approach, a 14 mm range inner diameter for stem portion  201  may be provided; in contrast, the corresponding ID for the original baffle shown in U.S. Pat. No. 8,356,731 is about 10 mm, or nearly a 100% cross-sectional area increase in the area for water to flow through. 
         [0028]    Referring to  FIG. 3 , as compared to its location at FIGS. 27-29 of U.S. Pat. No. 8,356,731 (in Which the lowermost location of floating ball  540  is above the bottom edge of cold tank  505 , as shown in FIG. 28B of the &#39;731 patent), the lowermost position of floating ball  210  has been relocated to a lower location, below the bottom wall  115 A of cold tank  115 . This relocation allows the cold water in baffle stem portion  201  to be restricted so that it remains in the cold water zone. Floating ball  210  is now located at the top edge of the hot water zone, the interface between cold and hot zone, to best separate the hot and cold water in baffle tube  201 . 
         [0029]    As a non-limiting example, for explanatory purposes, when floating ball  210  is in its uppermost position, the cold zone temperature may be close to the cold tank temperature of about, for example, 10° C., Similarly, the hot zone temperature may be close to the hot tank temperature of about, for example, 85° C. However, this assumes little or no water exchange. In reality, water can still move up and down so the cold and hot zone temperature separation is not a clear cut line, but rather a band. 
         [0030]    Accordingly, by using a plastic hot tank intake thread piece  165 , in conjunction with a new, lowered location for restrictor (e.g. floating ball)  210 , a straight cold/hot zone separation line is now formed at the bottom of the cold tank, as represented by the opposed arrows on  FIG. 3 . 
         [0031]    As noted above,  FIGS. 2 and 3  are alternative embodiments. Using the spiral tubing ( 130 ) approach of  FIG. 2 , floating ball  210  need not be moved down to the location illustrated in  FIG. 3  but, instead, can remain inside the baffle  200 . Also, with the  FIG. 2  embodiment, intake thread portion  165  need not be plastic, and the shape of thread portion  135  need not be changed to mate with thread portion  165 . Conversely, these changes are made in the  FIG. 3  embodiment to accommodate the fact that spiral tubing is not used. 
         [0032]    The above description is not intended to limit the meaning of the words used in the following claims that define the invention. Other systems, methods, features, and advantages of the present invention will be, or will become, apparent to one having ordinary skill in the art upon examination of the foregoing drawings, written description and claims, and persons of ordinary skill in the art will understand that a variety of other designs still failing within the scope of the following claims may be envisioned and used. For example, consumable liquids other than water, such as but not limited to carbonated beverages, may be dispensed. It is contemplated that these or other future modifications in structure, function or result will exist that are not substantial changes and that all such insubstantial changes in what is claimed are intended to be covered by the claims. 
         [0033]    The following terms are used in the claims of the patent as filed and are intended to have their broadest meaning consistent with the requirements of law. Where alternative meanings are possible, the broadest meaning is intended. All words used in the claims are intended to be used in the normal, customary usage of grammar and the English language.