Abstract:
A refrigeration device including a heat-insulated housing, which contains a storage compartment, a water tank, a fan for propelling a stream of cold air that passes through an evaporator and a distribution unit for the controlled distribution of the stream of cold air along at least two circulation paths, the first of which is in closer thermal contact with the water tank than the second.

Description:
This application is a divisional of U.S. patent application Ser. No. 12/085,939, filed May 28, 2008, which is the U.S. national phase of International Application No. PCT/EP2006/067964 filed Oct. 31, 2006, which designated the U.S. and claims priority to German Application No. 102005057165.4 filed Nov. 30, 2005, the entire contents of each of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     The present invention relates to a refrigeration appliance having a heat-insulating housing, a storage compartment for refrigerated items that is accommodated in the housing, and a water reservoir. A refrigeration appliance of this kind is known from WO 03/033976 A1. 
     The water reservoir of such a refrigeration appliance generally serves for supplying a drinking water dispenser which is mounted on an external surface of the housing of the refrigeration appliance and is in thermal contact with the storage compartment in order to ensure that its contents, and hence the drinking water drawn off at the dispenser, are cooled. 
     In order to prevent the contents of the reservoir from freezing at temperatures of the storage compartment below 0° C., the reservoir in the known refrigeration appliance is incorporated in an insulating layer of the door so that it assumes a temperature between that of the storage compartment and the ambient temperature. 
     Embedding the reservoir in insulation material on all sides means that when water has been drawn off and the reservoir is replenished with fresh water, it takes a very long time for the contents of the reservoir to assume their stationary temperature once more. Furthermore, the storage compartment must have a considerably lower temperature than the desired stationary temperature of the reservoir so that the latter temperature reaches a value that is acceptable to the user; in other words, the storage compartment must be at freezing temperature. A further problem is that the temperature in the reservoir is dependent on the ambient temperature of the refrigeration appliance. 
     BRIEF SUMMARY 
     The object of the present invention is to create a refrigeration appliance with a water reservoir which permits the temperature of the water reservoir to be set independently of the ambient temperature and the temperature of the storage compartment. 
     The object is achieved according to the invention by means of a refrigeration appliance having a heat-insulating housing, a storage compartment for refrigerated items that is accommodated in the housing, and a water reservoir, said refrigeration appliance having a blower for propelling a cold air stream running via an evaporator and a distributor device serving for the controlled distribution of the cold air stream over at least two circulation paths, of which the first is in closer thermal contact with the water reservoir than the second. By regulating the cold air throughput rates over the two circulation paths it is possible to keep both the storage compartment and the water reservoir at setpoint temperatures which can be specified independently of one another. 
     In the simplest case the control can be set permanently by the manufacturer or user of the refrigeration appliance, e.g. by adjusting passage cross-sections of the two circulation paths, in order to obtain a volume distribution of the cold air stream over the two circulation paths that results in a desired cooling of the water reservoir. 
     Alternatively the water reservoir can also be assigned a temperature sensor, and the distributor device is set up to regulate the cold air throughput over the first circulation path as a function of the temperature measured by the temperature sensor. 
     A sensor for detecting or measuring the volumetric flow rate of water through the reservoir can also be provided in order to determine the cooling requirement of the reservoir in a simple manner. 
     According to a simple embodiment, the water reservoir is disposed in the storage compartment, and the storage compartment has at least two inlet apertures for the cold air stream, of which one, which is to be assigned to the first circulation path, is oriented toward the reservoir. With a layout of this kind, the water reservoir is blasted with fresh cold air via said outlet aperture before the air disperses in the storage compartment, and in this way the reservoir can be preferentially cooled. In other words, although the water reservoir is contained in the storage compartment, it can assume a temperature which lies significantly below the average temperature of the storage compartment. 
     In order to avoid a strong influx of heat into the reservoir from the surrounding storage compartment, the reservoir can be disposed directly on a wall of the heat-insulating housing or in a recess in said wall. 
     According to a second embodiment, the reservoir is disposed outside of the storage compartment, and the first circulation path has an upstream section which runs via the reservoir and a downstream section which runs through the storage compartment. In this case, too, the reservoir can be cooled more strongly than the storage compartment. Air which has already been warmed up somewhat at the reservoir can subsequently be used also for cooling the storage compartment. This is beneficial in particular when the temperature difference between reservoir and storage compartment is great, e.g. when the storage compartment has a larder compartment through which the first circulation path runs after passing through the reservoir. 
     If the temperature of the reservoir is only slightly lower than that of the storage compartment, or if the temperature of the storage compartment is lower than that of the reservoir, it is not beneficial to route air warmed at the reservoir into the storage compartment. In this case the reservoir is beneficially disposed outside of the storage compartment, and the first circulation path runs via the reservoir, bypassing the storage compartment. A layout of this kind can also be used if the reservoir temperature is lower than that of the storage compartment. A refrigeration appliance housing in which the first circulation path is separated from the storage compartment is therefore suitable both for a refrigerator and for a freezer and on account of this versatility can be economically mass-produced. 
     In these latter cases the reservoir is preferably incorporated in an insulating layer of a wall of the housing. 
     In such an arrangement the first circulation path can run through between the storage compartment and the reservoir. In order to keep the thickness of the wall small, it can also be beneficial if the first circulation path runs at an angle delimited on one side by the reservoir and on the other side by the storage compartment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the invention will emerge from the following description of exemplary embodiments with reference to the attached figures, in which: 
         FIG. 1  shows a schematic section through a refrigeration appliance according to a first embodiment of the invention; 
         FIG. 2  shows a section according to a second embodiment; 
         FIG. 3  shows a section according to a third embodiment; 
         FIG. 4  shows a section according to a fourth embodiment; 
         FIG. 5  shows a view of the inside of the door of the refrigeration appliance from  FIG. 4 ; and 
         FIG. 6  shows a partial section along the line VI-VI from  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a schematic section through a refrigerator in no-frost design which represents a first exemplary embodiment of the invention. A carcass  1  of the refrigerator is assembled in a manner known per se from a solid outer skin and an inner container  3  delimiting a storage compartment  2  and deep-drawn as a single piece from plastic, and a space between outer skin and inner container  3  is filled with insulating foam material. 
     An evaporator  6  and a blower  7  are contained in a chamber  5  separated from the storage compartment  2 . An inlet aperture  17  is formed between the chamber  5  and the storage compartment  2  at an end of the chamber  5  facing the door  8 . Since the inlet aperture lies outside the sectional plane of the figure, it is indicated in the latter as a dashed outline. Extending adjacent to the rear wall of the carcass  1  is a distributor channel  9  which communicates on the one side with the chamber  5  and on the other side with the storage compartment  2  via a plurality of vertically distributed apertures  10 . Attached at the inlet of the distributor channel  9  is a flap  11  which in the position shown closes the distributor channel  9  and reveals an aperture  38  which leads into the storage compartment  2  adjacent to a water reservoir  12 . The rear walls of the reservoir  12  and of the inner container  3  delimit a reservoir cooling duct  13  through which cold air flows after passing through the aperture  38  before it disperses in the storage compartment  2 . 
     A supply conduit  14  of the reservoir is provided for the purpose of being connected to a public drinking water network; a delivery conduit  15  is routed through a hinge of the door  8  to a drinking water dispenser  16  disposed centrally in the door  8 . The supply conduit  14  can simultaneously serve to supply an ice maker, though this is not shown in the figure because it is not directly related to the invention. 
     In the schematic of  FIG. 1  it is shown that the reservoir cooling duct  13  extends along the rear side of the roughly cube-shaped reservoir  12  placed in the storage compartment  2 . In order to restrict an exchange of heat of the reservoir  12  with the rest of the storage compartment  2 , the reservoir cooling duct  13  can additionally extend also via side walls of the reservoir  12  outside of the sectional plane of the figure, or the reservoir  12  can extend in the width direction of the carcass  1  in each case from one side wall to the opposite one in order to immediately adjoin its insulating layer and so prevent an exchange of heat with the rest of the storage compartment by way of the side walls. 
     In a variation shown in  FIG. 2  the reservoir cooling duct  13  is also routed along the underside and front side of the reservoir  12  and extends from there as far as the inlet aperture  17  of the chamber  5 . This design permits the cold air used for cooling the reservoir  12  to be routed totally separately from that which flows through the rest of the storage compartment  2 . In contrast to the embodiment of  FIG. 1 , this means that no temporary warming-up of the storage compartment  2  can occur if a large amount of water is drawn off from the reservoir  12  and replaced by warm water, with the result that the air in the reservoir cooling duct  13  becomes warmer than in the rest of the storage compartment  2 . 
       FIG. 3  shows a third embodiment of the refrigeration appliance according to the invention. As with the previously considered embodiments, a chamber  5  containing evaporator  6  and blower  7  is divided off in the carcass  1  above the storage compartment  2 , and a flap  11  is movable between a position shown in the figure, in which it closes a distributor channel  5  running along the rear wall of the storage compartment  2  and opens a reservoir cooling duct  13 , and a position in which it opens the distributor channel  9  and closes the reservoir cooling duct  13 . In this embodiment the reservoir cooling duct  13  comprises a first section  18 , which runs inside the carcass  1  to the door  8 , and a second section  19 , which runs in the interior of the door  8  between the reservoir  12  and the storage compartment  2 . The sections abut each other at two inclined surfaces of the carcass  1  and the door  8  which lie opposite and parallel to each other when the door  8  is closed and at the same time hold a rubber seal  39  compressed. 
     In the schematic shown in  FIG. 3  the second section  19  leads under the reservoir  12  into the storage compartment  2 . Alternatively it would be possible to route the second section  19  upward again inside the door  8  and back to the inlet aperture (not shown) of the chamber  5  in order in this way to implement mutually separate flow paths through the storage compartment  2  on the one hand and along the reservoir  12  on the other, and by this means prevent air heated at the reservoir above the temperature of the storage compartment  2  being emitted into the storage compartment  2 . 
     Instead of the mounting of the reservoir  12  in the door  8  above the drinking water dispenser  16 , as shown in  FIG. 3 , it would also be conceivable to place an ice maker in this area and to arrange the reservoir instead in the door at the level of the drinking water dispenser  16 . 
     In the embodiment shown in  FIG. 4 , the flow direction of the air in the chamber  5  is from back to front, in contrast to the embodiments considered above. Distributor channels  20  (see  FIG. 5 ) for distributing cold air from the chamber  5  in the storage compartment  2  extend outside of the sectional plane of  FIG. 4  in the door  8  and for reasons of clarity are not shown in  FIG. 4 . A valve  21  is switchable between a position in which it connects the distributor channels  20  with the chamber  5  and a position in which it feeds a reservoir cooling duct  13  running in the inside of the door  8 . Parts of the reservoir cooling duct  13  which lie outside of the sectional plane of  FIG. 4  are shown in the figure as a dashed outline. The reservoir cooling duct  13  runs along lateral walls of the reservoir  12 , passes a recess  22  which is located under the reservoir and contains the water dispenser  16 , and extends finally as far as a transition piece  23  at the bottom edge of the door  8 , to which bottom edge an intake duct  24  is joined in the carcass  1 . Said intake duct  24  extends under the base of the storage compartment  2  and along its rear wall. Intake apertures  25  formed in the area of the rear wall between intake duct  24  and storage compartment  2  enable air to be recirculated from the storage compartment  2  to the evaporator chamber  5 . 
       FIG. 5  shows a view of the rear side of the door  8 . Located in an inclined surface  26  in the upper region of the door are three openings  27 ,  27 ,  28 , opposite which are located corresponding openings of the carcass  1  when the door  8  is closed, and of which in a first position of the valve  21  the two outer openings  27  are fed with cold air and in a second position of the valve  21  the middle opening  28  is fed with cold air. The two openings  27  belong to distributor channels  20  which extend vertically downward along the inside of the door  8  and in each case have a plurality of outlet apertures  29  at different heights via which cold air is delivered in a distributed manner over the height of the storage compartment  2 . 
     The opening  28  belongs to the reservoir cooling duct  13  that runs between the two distributor channels  20  and the outline of which, hidden in the figure, is likewise indicated in the drawing by a dashed line. The reservoir cooling duct  13  is delimited from the storage compartment  2  by a flat plastic shell  30  which extends from the opening  28  over essentially the full height of the door as far as an opening  40  at its bottom edge and in its upper region has a bulge  31  projecting into the storage compartment  2  and concealing both the reservoir  12  and the recess  22 . 
     As can be seen more precisely in the section shown in  FIG. 6 , the door  8 , like the carcass, is constructed from a solid outer skin, an inner wall  33  deep-drawn from plastic and, enclosed therebetween, a layer  34  of insulating foam material and has a cavity  32  covered by the shell  30  and in which the reservoir  12  is housed. In the schematic shown in  FIG. 6 , the reservoir cooling duct  13  extends on both sides of the reservoir  12  at an angle  36  which is delimited on one side by side walls of the reservoir  12  and on the other side by the shell  31  which separates the cooling duct  13  from the storage compartment  2 . A gap  35  between the reservoir  12  and the shell  31  is filled with insulating material in order to decouple the reservoir  12  thermally from the storage compartment  2  to a large extent. The gap  35  could also be left empty, however, in order to act equally as the reservoir cooling duct  13 . 
     In order to intensify the heat exchange between the reservoir  12  and the air flowing in the cooling duct  13 , the reservoir  12  can be provided with projecting cooling fins  37 , as shown. 
     Because of the arrangement of the reservoir  12  in one of the insulating walls of the refrigeration appliance housing between the cooled storage compartment  2  and the environment, the reservoir  12  takes on a temperature which lies between that of the storage compartment  2  and that of the environment, without the necessity for the cooling duct  13  to be impinged upon by cold air. Supplying the duct  13  with cold air is only necessary if a lower temperature of the water in the reservoir is desired than ensues automatically in the thermal equilibrium between storage compartment and environment, or if a fast cooling-down of the reservoir contents is desired. In order to ensure the latter, the temperature of the water in the reservoir can, as explained above, be measured with the aid of a temperature sensor (not shown) and the cooling duct  13  impinged upon by cold air if the measured temperature lies above a setpoint value; it is, however, also possible to detect that or register how much water is being drawn off at the drinking water dispenser  16  in order subsequently to feed a fixed amount of cold air or an amount proportional to the drawn-off water volume into the cooling duct  13  and so quickly cool down water that has flowed in to replenish the reservoir  12 . Controlling the cooling of the reservoir  12  in such a manner can be implemented economically in particular in refrigeration appliances that are equipped with an integrated water filter and a measuring apparatus for recording the accumulated water throughput through the filter. A measuring apparatus of said kind traditionally serves for estimating, on the basis of the water consumption, when the filter is exhausted and has to be replaced; however, it can also be readily used for qualitatively or quantitatively estimating the cooling requirement at the water reservoir  12 .