Patent Document

BACKGROUND OF INVENTION 
     This invention relates to water dispensing systems for refrigerators, and, more particularly, to filtered water dispensing systems for refrigerators. 
     Refrigerators typically include water storage tanks for cooling and storage of water to be dispensed. In one type of dispensing system, a serpentine water storage tank is employed with a water filter. See, for example, U.S. Pat. No. 3,511,415. Further, some dispensing systems include a water filter adjacent to a water storage tank located in a fresh food compartment of the refrigerator. 
     A filter adjacent to a water storage tank in thermal communication with a fresh food compartment of a refrigerator requires a first plumbing joint connecting the tank and filter and a second plumbing joint connecting the filter to an outlet line. Over time, these joints are susceptible to unpleasant-and undesirable leakage. Also, adding a filter to the water dispensing system requires extra space that could otherwise be used for refrigerator compartment space, and increases material costs and assembly costs of dispensing system production. 
     SUMMARY OF INVENTION 
     In one aspect, a chilled water supply system for a refrigerator is provided. The system comprises a water storage tank comprising an outlet leg, and a filter media disposed within said outlet leg. 
     In another aspect, a water dispensing system for a refrigerator is provided. The system comprising a water storage tank comprising at least an inlet portion for storage of unfiltered water and an outlet portion comprising a filter media for filtering said unfiltered water before use. 
     In an additional aspect, a refrigerator is provided. The refrigerator comprises a fresh food compartment and a water dispensing system in thermal communication with said fresh food compartment,. The water dispensing system comprises a water storage tank comprising at least an inlet portion for storage of unfiltered water and an outlet portion for discharging filtered water. A perforated tube is disposed within said outlet portion and comprises an upstream end and a downstream end, a base extending from said upstream end and an end cap extending coupled to said downstream end. A filter media disposed about said tube between said end cap and said base. 
     In still another aspect, a method of supplying chilled filtered water from water dispensing system including an integral water tank and filter assembly having an inlet line and an outlet line is provided. The method comprises the steps of introducing warm water into the tank through the inlet line, passing the introduced water through the tank to chill the water, filtering the chilled water while the water is within the tank, and discharging the chilled water to the outlet line. 
     In a further aspect, a method of supplying chilled filtered water with a refrigerator dispensing system is provided for a refrigerator including a fresh food compartment and the dispensing system including an integral water tank and filter assembly, the tank having an inlet, an outlet, and a flow path therebetween. The method comprises the steps of fastening the tank in a substantially horizontal position in thermal communication with the fresh food compartment, connecting the tank inlet to a water supply inlet line such that relatively warm water is introduced into the tank through the inlet line, connecting the tank outlet to a dispenser system outlet line, passing the introduced water through the flow path to chill the introduced water, filtering the chilled water while the water is within the tank just prior to use; and discharging the chilled water to the outlet line. 
     In still a further aspect, a method of supplying chilled filtered water with a refrigerator dispensing system is provided, the refrigerator including a fresh food compartment and the dispensing system including an integral water tank and filter media disposed about a tube within the tank, the tube having a downstream end, the tank having an inlet and a serpentine flow path therebetween. The method comprising the steps of removably fastening the tank in a substantially horizontal position in thermal communication with the fresh food compartment, connecting the tank inlet to a water supply inlet line such that relatively warm water is introduced into the tank through the inlet line, connecting the downstream end of the tube to a dispenser system outlet line, passing the introduced water through the flow path to chill the introduced water, passing the introduced water radially through the filter media and into the central tube just before use, and discharging the chilled water from the tube downstream end to the dispenser system outlet line. 
     In still an additional aspect, a replacement kit for a water storage tank and water filter of a chilled water supply system for a refrigerator including a fresh food compartment floor is provided. The replacement kit includes an integral serpentine water storage tank and water filter media, said water filter media within an outlet leg of said tank, and a quick release fastener configured to rapidly attach said unit to the fresh food compartment floor. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a partially broken-away top cross-sectional view through an integral water tank and filter. 
     FIG. 2 is an exploded top view, in partial cutaway, of a second exemplary embodiment of an integral water tank and filter. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 is a top cross sectional view of an exemplary water dispensing system  10  located in an exemplary lower portion  12  of an exemplary refrigerator  14 . Refrigerator  14  includes a fresh food compartment  16  and a freezer compartment  18 . Compartments  16  and  18  are separated by an insulation barrier  20  and two plastic coating layers  22  and  24 . System  10  is located in thermal communication with compartment  16 , and, in one embodiment is positioned in fresh food compartment  16  adjacent a floor thereof. It is recognized, however, that the benefits of the present invention accrue to many types of refrigerators beyond exemplary refrigerator  14 , and further that the benefits may be realized by positioning water dispensing system  10  elsewhere in a refrigerator than, for example, lower portion  12 . 
     System  10  includes an inlet line  26 , a water tank  28 , and an outlet line  30 . Water tank  28  is fabricated from known methods, such as blow molding, and is serpentine shaped, i.e. curves back and forth, to increase a length of its flow path between an inlet line  26  and outlet line  30  while conserving space. Serpentine water tank  28  is shaped like an inverted “S”, although other serpentine shapes could be used having any desired number of bends  32 . Serpentine water tank  28  is attached to a rectangular bar  34  with two openings  36  and  38 . Lower portion  12  has two vertical studs (not shown) which pass through openings  36  and  38 . Wing nuts  40  and  42  are attached to the vertical studs to hold bar  34  to a floor  44  of refrigerator lower portion  12 . Inlet line  26  passes through floor  44  and into compartment  16  where it is connected to an inlet  46  of tank  28 . Outlet line  30  is connected to an outlet  48  of tank  28  and then passes through barrier  20  and a freezer door  50  to a water dispenser (not shown) by way of a vertical portion  52  of outlet line  30 . System  10  receives water entering system  10  through inlet line  26  as shown by arrow  53 . Unfiltered water is cooled during its passage through serpentine tank  28  and ultimately filtered and discharged as cooled water through outlet line  30  to a water dispenser (not shown.) just prior to use. 
     Serpentine tank  28  includes a longitudinally extending inlet leg  54 , a longitudinally extending center leg  55  and a longitudinally extending outlet leg  56 . Inlet leg  54  receives warm water  57 , which passes through leg  54  for a sufficient time to allow heat to escape from warm water  57  to produce slightly cooled water  58 . Slightly cooled water  58  exits inlet leg  54  and enters center leg  55 . Additional heat escapes from slightly cooled water  58  during its passage through center leg  55  to produce cooled water  59 . Cooled water  59  exits center leg  55  and enters outlet leg  56 . During its passage through outlet leg  56 , further heat escapes from cooled water  59  before passing through a cylindrical filter media  60  and a collection center tube  62  into outlet tube  48 . Filter media  60  is fabricated from known materials and is held within outlet leg  56  by an outlet cover such as end cap  64  or other known cover members. End cap  64  includes a boss  66  that holds center tube  62  within filter media  60 . 
     While the illustrated embodiment includes a substantially parallel inlet leg  54 , center leg  55 , and outlet leg  56 , it is recognized that the legs of the water tanks need not be parallel in alternative embodiments to achieve at least some of the benefits of the present invention. Additionally, it is appreciated that the benefits of the invention may be obtained in alternative embodiments with U-shaped water tanks, or other non-serpentine shaped water tanks apparent to those in the art. 
     Filter media  60  is spaced radially inward from outlet leg  56 , and collection center tube  62  includes a plurality of perforations or inlet openings  66  to facilitate uniform flow of water through media  60  and into center tube  62 . This configuration allows use of larger surface area filters, providing smaller pressure drops during flow than known comparable compact removable filter elements. Consequently, cooled, filtered water flows from center tube  64  to outlet tube  48 , where outlet tube  48  delivers cooled, filtered water to outlet line  30 . From outlet line  30 , water is dispensed by a dispensing system (not shown) upon user demand. Fresh food compartment door  68  forms a seal  70  with a door opening  72 , to keep compartment  16  cool by normal operation of refrigerator  14 , which, in turn, cools water in system  10 . In one embodiment, the dispenser mechanism also dispenses crushed ice and cubed ice, and is located on a front of freezer door  50  to provide a relatively direct path for ice. In alternative embodiments, the dispenser mechanism is located elsewhere on refrigerator  14 . 
     Water tank  28  with integral filter media  60  may be easily removed by disconnecting wing nuts  40  and  42  from bar  34  to release tank  28 . The entire tank  28 , together with filter media  60 , is disconnected from inlet line  26  and outlet line  30  and removed through door opening  72 . Another tank  28  and integral filter media  60  is replaced by reconnecting inlet line  26  and outlet line  30  and fastening wing nuts  40  and  42  to bar  34 . Thus, a reliable water filter assembly is provided within the water storage tank to conserve space of the refrigerator fresh food compartment, and simple hand installation and removal without tools reduces assembly costs and maintenance difficulties. 
     FIG. 2 is an exploded top view, in partial cutaway, of outlet leg  56 . An upstream direction is shown by arrow  76  and a downstream direction by arrow  78 . Center tube  62  includes an annular base  84  attached to a center tube upstream end  86  that restrains filter media  60  against movement upstream. Cylindrical filter media  60  includes a central opening therethrough to receive center tube  62 . End cap  90  is ultrasonically welded to boss  66  on a downstream end  94  of tube  82  to capture filter media  60  between base  84  and cap  90 . Filter media  60  is a thick cylindrical tube configured to fit within outlet leg  56 . Filtering of water in outlet leg  56  allows storage of water in tank  28  (shown in FIG. 1) in an unfiltered condition until just before use. Thus, bacterial suppressing chlorine treatments frequently employed in municipal water treatment systems are not filtered from the water in the tank until just before use, thereby minimizing bacterial re-growth in water tank  28  that may otherwise occur if water was filtered within water tank inlet leg  54  or center leg  56  (shown in FIG.  1 ). 
     In alternate embodiments, outlet leg  56  and filter media  60  vary in length. Further alternate embodiments include varying numbers of water tank legs, subject to limitations of the size of compartment housing. Other leg configurations of inlet leg  54  (shown in FIG. 1) and center leg  55  (shown in FIG. 1) may be employed in various alternative embodiments within the scope of the present invention. End cap  90  is ultrasonically welded to a downstream end  96  of leg  56  to form a permanently sealed water dispensing system  10 . System  74  is removably attached with wing nuts (not shown) as described above in relation to FIG.  1 . While in the described embodiment, the storage tank and filter media are a disposable unit, it is contemplated that a removable end cap may be provided such that the filter media may be replaced and the water tank be reused in an alternative embodiment within the scope of the invention. 
     In a further embodiment, the above-described integral filter/tank of dispenser system  10  is positioned horizontally or slightly inclined to facilitate escape of air in the tank when the tank is initially filled, as well as facilitating uniform passage of cooling air around the serpentine tank. Horizontal placement of the tank also permits the tank to be placed adjacent a floor of a fresh food compartment of the refrigerator where freezing of water in the tank is least likely. 
     A disposable and easily replaced integral tank and filter is therefore provided that eliminates plumbing joint connections to and from conventional water filters located adjacent, or outside, conventional storage tanks. Replacement of the water tank at the time the filter replacement reduces likelihood of late-in-life water tank leaks. 
     While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

Technology Category: 2