Patent Application
20090158768
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.
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.
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.
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
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
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
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.
As shown in
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.
