Abstract:
A temperature controlled surface in a refrigerator that includes a heat exchanger configured to have the cooling medium flow therethrough to be cooled in thermal communication with a freezer compartment of the refrigerator. A second heat exchanger disposed downstream of the first heat exchanger and configured to have the cooling medium flow therethrough to cool the temperature controlled surface. A pump configured to flow the cooling medium through the first and second heat exchangers. A first heat exchanger is disposed downstream of the storage tank and is configured to have the cooling medium flow therethrough to be cooled. A second heat exchanger is disposed downstream of the first heat exchanger and is configured to have the cooling medium flow therethrough to cool the air and any contents within the temperature controlled compartment.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to temperature-controlled devices, and more particularly, to temperature controlled devices utilizing a secondary cooling loop from a primary cooling source. 
     It is generally known to provide refrigeration systems for commercial or institutional food sales or food service facilities such as supermarkets, grocery stores, cafeterias, etc. These refrigeration systems operate with refrigeration or cooling devices such as temperature controlled cases (individually or in groups) that use air-cooled or water-cooled condensers supplied by a rack of compressors. For example, modern supermarket applications typically have many individual or grouped refrigeration devices located throughout the shopping or display area of the supermarket. Each refrigeration device is provided with a cooling interface such as an evaporator or cooling coil that receives refrigerant from the refrigeration system in a closed loop configuration where the refrigerant is expanded to a low pressure and temperature state for circulation through the cooling interface to cool the space and objects within the refrigeration device. In such applications, one or more condensers are typically located either outside, on the roof, or in a machine room or back room adjacent to the shopping or display area where the refrigeration devices are located and are used to cool the refrigerant that is distributed to all or a group of these refrigeration devices. 
     Similarly, there has become a proliferation of refrigeration devices in use in residential applications. These devices can include but are not limited to several refrigerators with icemakers, ice machines, freezers, wine chillers and can coolers. Typically, each of these devices utilizes a self-contained evaporator/condenser cooling circuit. These evaporator/condenser circuits, while capable of high capacity and are efficient, they are expensive to manufacture and maintain. The devices requiring cooling may use other forms of heat exchange such as thermoelectric cooling. However, thermoelectric cooling has low efficiency, low capacity, and a high thermal inertia. 
     While evaporator/condenser cooling circuits are generally an efficient cooling means, the system is driven by a refrigeration compressor system. The compressor utilizes electricity through a pump to compress a refrigerant. Each compressor occupies space and can be a source of noise. The refrigerant is cooled in a coil exposed to the ambient air of the residence or other location of the circuit. The refrigerant is then depressurized reducing the temperature of the refrigerant. The reduced temperature refrigerant is used in a heat exchanger within the device to be cooled to reduce the temperature. Each of these stages has inefficiencies in the form of heat or electrical consumption. 
     Accordingly, it would be advantageous to provide a distributed refrigeration system having a stand-alone refrigeration device with a self-contained refrigeration system that is suitably efficient for residential viability. It would be further advantageous to provide a distributed refrigeration system having a sufficiently low noise level. It would also be advantageous to provide a distributed refrigeration system that reduces the amount of refrigerant or evaporative/condenser systems thus reducing potential environmental hazards. It would also be advantageous to provide a distributed refrigeration system permitting the connection of devices thereto and having applications that are not possible where an individual refrigeration circuit would be required. It would be further advantageous to provide a distributed refrigeration system having a central electrical unit in which all electrical functions of the distributed refrigeration unit are pre-wired at the factory and require only a single electrical power hook up when installed in a home. 
     Accordingly, it would be advantageous to provide a distributed refrigeration system having any one or more of these or other advantageous features. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one aspect, a refrigerator is provided. A temperature controlled compartment in a refrigerator that includes a heat exchanger configured to have the cooling medium flow therethrough to be cooled in thermal communication with a freezer compartment of the refrigerator. A second heat exchanger disposed downstream of the first heat exchanger and configured to have the cooling medium flow therethrough to cool the temperature-controlled compartment. A pump configured to flow the cooling medium through the first and second heat exchangers. A first heat exchanger is disposed downstream of the storage tank and is configured to have the cooling medium flow therethrough to be cooled. A second heat exchanger is disposed downstream of the first heat exchanger and is configured to have the cooling medium flow therethrough to cool the air and any contents within the temperature controlled compartment. 
     In another aspect of the invention, a method is used for a chilled compartment in a refrigerator. First, flowing a refrigerant through a cooling system to cool a first interior compartment of the refrigerator. Then, flowing a cooling medium different from the refrigerant through a first heat exchanger disposed within the first interior compartment to decrease the temperature of the cooling medium. Finally, flowing the cooling medium through a second heat exchanger in thermal communication with the chilled compartment to reduce the temperature of the chilled compartment. 
     In yet another aspect of the invention, a refrigerator having a compartment cooling section configured to cool an interior compartment of the refrigerator. The compartment cooling section has a first heat exchanger configured to have a refrigerant flow through it to absorb heat. An ice producing apparatus is configured to produce ice and to deliver the ice through an opening in a door of the refrigerator. The ice producing apparatus has a storage tank configured to store a cooling medium. It also has a second heat exchanger disposed downstream of the storage tank that is configured to have the cooling medium flow through it to be cooled. An ice mold with at least one cavity that is configured to retain water therein is in thermal communication with a third heat exchanger that is disposed downstream of the second heat exchanger and configured to have the cooling medium flow through it to freeze the water in the ice mold to produce ice. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a known refrigerator. 
         FIG. 2  is a perspective view of the refrigerator of  FIG. 1  with the refrigerator doors open. 
         FIG. 3  is a schematic view of an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     It is contemplated that the teaching of the description set forth below is applicable to all types of refrigeration appliances, including but not limited to refrigerators but include a standalone refrigeration unit or may be connected to an air conditioning unit. The present invention is therefore not intended to be limited to any particular refrigeration device or configuration of cooling circuit  100  for the temperature controlled medium. 
       FIGS. 1 and 2  illustrate a side-by-side refrigerator  100  including a fresh food compartment  102  and freezer compartment  104 . Freezer compartment  104  and fresh food compartment  102  are arranged in a bottom mount configuration where the freezer compartment  104  is below the fresh food compartment  102 . The fresh food compartment is shown with French opening doors  134  and  135 . However, a single door may be used. Door or drawer  132  closes freezer compartment  104 . 
     The fresh food compartment  102  and freezer compartment  104  are contained within an outer case  106 . Outer case  106  normally is formed by folding a sheet of a suitable material, such as pre-painted steel, into an inverted U-shape to form top and sidewalls  230 ,  232  of case  106 . Mullion  114  is preferably formed of an extruded ABS material. As shown in  FIG. 2 , Mullion  114  separates the fresh food compartment  102  and the freezer compartment  104 . 
     Door  132  and doors  134 ,  135  close access openings to freezer and fresh food compartments  104 ,  102 , respectively. Each door  134  and  135  is mounted by a top hinge  136  and a bottom hinge  137  to rotate about its outer vertically oriented edge between an open position, as shown in  FIG. 2 , and a closed position shown in  FIG. 1  closing the associated storage compartment. 
     In accordance with known refrigerators, refrigerator  100  also includes a machinery compartment (not shown) that at least partially contains components for executing a known vapor compression cycle for cooling air in the compartments. The components include a compressor (shown schematically in  FIG. 3  as  151 ), a condenser (shown schematically in  FIG. 3  as  152 ), an expansion device (shown schematically in  FIG. 3  as  155 ), and an evaporator (shown schematically in  FIG. 3  as  156 ) connected in series and charged with a refrigerant. The evaporator is a type of heat exchanger that transfers heat from air passing over the evaporator to a refrigerant flowing through the evaporator, thereby causing the refrigerant to vaporize. The cooled air is used to refrigerate one or more fresh food or freezer compartments via fans (shown schematically in  FIG. 3  as  157 ). Collectively, the vapor compression cycle components in a refrigeration circuit, associated fans, and associated compartments are referred to herein as a sealed system. The construction of the sealed system is well known and therefore not described in detail herein, and the sealed system is operable to force cold air through the refrigerator  100 . 
     The secondary loop temperature control circuit or distributed temperature system of the present invention may be used for a variety of distributed temperature control applications where localized temperature control is desired. These applications may including more than one temperature controlled compartments or regions that may be zoned with valves or other mechanisms. 
       FIG. 3  is a schematic view of an embodiment of the invention. The refrigerator  100  contains a temperature control circuit, the temperature control circuit is a vapor-compression circuit  150 , which is known in the art. The vapor compression circuit  150  has a compressor  151  for compressing a working fluid. When compressed the working fluid becomes heated, heat is removed in coil  152 . The working fluid is decompressed or vaporized at  155  thereby further cooling the working fluid. The working fluid passes through medium heat exchanger  310  before entering evaporator  156 . Evaporator  156  may have a fan  157  to circulate air from freezer compartment  104  in a plenum (not shown) past evaporator  156  and back to freezer compartment  104  thereby cooling freezer compartment  104 . 
     As shown in  FIG. 3 , heat exchanger  310  thermally connects the vapor-compression circuit  150  with the distributed temperature system of the present invention. However, heat exchanger  310  may not be directly connected to the vapor compression circuit  150  and may utilize heat transfer to the freezer compartment  104  as a means of cooling the working medium in the distributed temperature system. It can be appreciated that by locating the heat exchanger  310  between compressor  151  and the coil  152 , heat may be transferred to the working medium of the distributed temperature system of the invention. 
     The distributed temperature system utilizes a working medium, hereinafter “medium”. The medium is preferably a food safe medium, such as propylene glycol. The working medium flows in tubes or conduits connecting the components of the system. 
     Heat exchanger  310  has a coil  311  as a part of the vapor compression circuit  150  and a coil  312  as a part of the distributed temperature system. The coils  311  and  312  are in thermal communication generally by a working fluid thereby transferring heat from one system to the other. It can be appreciated that coil  312  may be removed and the medium may flow around coil  311  thereby transferring heat directly to the medium. 
     Tank  301  of the distributed temperature system allows a quantity of the medium to be maintained in the system. The tank  301  may contain a means for adding additional medium to the distributed temperature system. 
     Pump  302  moves the medium from tank  301  past or through heat exchanger  310  to output ports  321 ,  322  and  323 . Output ports  321  and  322  are provided in an exterior surface of the refrigerator  100 . It can be appreciated that any number of output ports  321 ,  322  can be provided in the exterior of refrigerator  100 . Output port  323  is provided on the interior of the refrigerator  100 . It can be appreciated that while only one output port  323  is shown in the freezer compartment  104  of refrigerator  100 , multiple output ports may be provided in either the freezer compartment  104  or fresh food compartment  102  of refrigerator  100 . 
     Similarly input ports  331  and  332  are also provided in an exterior surface of the refrigerator  100 . It can be appreciated that any number of input ports  331 ,  332  can be provided in the exterior of refrigerator  100 . Input port  333  is provided on the interior of the refrigerator  100 . It can be appreciated that while only one input port  323  is shown in the freezer compartment  104  of refrigerator  100 , multiple input ports may be provided in either the freezer compartment  104  or fresh food compartment  102  of refrigerator  100 . 
     By providing multiple output ports  321 ,  322 ,  323  and multiple input ports  331 ,  332 ,  333  multiple devices  400  may be connected to the distributed temperature system in parallel. By connecting the devices  400  in parallel each device  400  receives medium directly from heat exchanger  310 . In this configuration each device  400  receives medium of similar temperature. 
     Output ports  321 ,  322 ,  323  and input ports  331 ,  332 ,  333  are configured such that when no device is connected, flow through the disconnected port is prevented. One such configuration used to achieve this functionality, comprises a hydraulic quick disconnect with an internal valve, however, any interconnect may be used which prevents leakage of the medium when the port is not used. 
     Device  400  is connected to the distributed temperature system by similar quick disconnects at device input port  421  and device output port  431 . Medium flows into the device  400  to a tank  401 . Tank  401  may contain a volume of storage or may be a means of removing air from the device  400 . 
     Device heat exchanger  412  thermally connects the medium to the device  400 . Generally, heat is transferred by conduction between the heat exchanger  412  and device  400 . However, a fan  405  may be used to accelerate the transfer of heat between the device heat exchanger  412  and the device  400  in combination with convection heat exchange within device  400 . Further, a device pump  402  may be incorporated in the device  400  to facilitate flow of the medium. 
     Device  400  may also include an auxiliary output port  423  and auxiliary input port  433 . Auxiliary ports  423  and  433  permit the connection of additional devices serially with device  400 . 
     While the invention is described with reference to a vapor compression loop of a refrigerator, it is understood that any means of transferring heat to or from the medium within the heat exchanger of the secondary loop cooling circuit of the invention may be used. Further, the distributed temperature system may comprise a pair of circuits offering both a cooling circuit and a heating circuit. 
     Output ports  321 ,  322  and  323  or input ports  331 ,  332  and  333  may incorporate an electrical interconnect. The electrical interconnect being designed to facilitate communications between the device  400  and components of the distributed temperature system. Such communications may include a pump signal to activate pump  302 , a temperature signal indicating a temperature of the device  400 . 
     Device  400  may be any household device that must be kept at a temperature other then the ambient temperature within the house. Devices include a surface such a chilled surface to hold vegetable trays or for working with food or a heated surface for keeping foods or other items warm. Other devices include a stand-alone ice-maker or ice holder, a fast chill compartment, a chiller or heater for drinking water supply, a soda or beer (keg-orator) chiller, a dehumidifier heating or cooling side. Further applications for a distributed temperature system include a compartment for thawing food, a wine chiller, a glass chiller for frosted mugs/glasses or to quick chill a portable cooling device such as a cold pack or a cooler. 
     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.