US20120036874A1

US20120036874A1 - Active cooling of a compressor in an appliance

Info

Publication number: US20120036874A1
Application number: US12/855,369
Authority: US
Inventors: Jianwu Li; Stephanos Kyriacou
Original assignee: General Electric Co
Current assignee: Haier US Appliance Solutions Inc
Priority date: 2010-08-12
Filing date: 2010-08-12
Publication date: 2012-02-16

Abstract

A system for cooling a compressor for an appliance includes a water source, a compressor having an outer shell, the compressor being configured to compress a refrigerant during a cooling cycle of the appliance, and a fluid heat transfer device. The fluid heat transfer device is configured to receive water from the water source and apply the water to the outer shell for rejecting heat from the compressor.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application relates to U.S. patent application Ser. No. ______, filed on ______, entitled “EVAPORATIVE COOLING CONDENSER FOR HOUSEHOLD APPLIANCE”, GE Docket No. 242918.

BACKGROUND

The present disclosure generally relates to appliances, and more particularly to active cooling of a compressor in a refrigeration appliance.
Government regulations and consumer demand strongly encourage the development of low energy use appliances. Cooling and air-conditioning systems for appliances such as refrigerators consume a great deal of energy. Efforts to produce highly efficient appliances can be costly. For example, various approaches to energy-saving appliances have been developed that include the use of vacuum panels to decrease the amount of heat entering the refrigerator from the external environment. However, the use of vacuum panels requires the addition of expensive parts and increases the total cost of the appliance for the consumer.
The compressor in an appliance such as a refrigerator typically generates a significant amount of heat during operation. Generally, attempts to cool the compressor utilize air. Typically, fans are used to move air through the condenser then also to the compressor. Thus, the air reaches the compressor it is already warmed or at a temperature above the ambient temperature, and the cooling capacity is limited. It is estimated that with proper cooling, the energy efficiency rating (“EER”) of a compressor might be improved by approximately 3.5%.
Accordingly, it would be desirable to provide a system that addresses at least some of the problems identified.

BRIEF DESCRIPTION OF THE EMBODIMENTS

As described herein, the exemplary embodiments overcome one or more of the above or other disadvantages known in the art.
One aspect of the exemplary embodiments relates to a system for cooling a compressor for a household appliance. In one embodiment, the system includes a water source, a compressor having an outer shell, where the compressor is configured to compress a refrigerant during a cooling cycle of the appliance, and a fluid heat transfer device, the fluid heat transfer device being configured to receive water from the water source and apply the water to the outer shell for rejecting heat from the compressor.
In another aspect, the disclosed embodiments are directed to a method. In one embodiment, the method includes detecting an operation of a compressor in a refrigerant-based cooling appliance, and applying water to an external surface of the compressor at a rate configured to enhance an evaporation of the water and enable the compressor to reject heat.
In a further aspect, the disclosed embodiments are directed to a cooling system for a household appliance. In one embodiment, the cooling system comprises an evaporator, a compressor coupled to the evaporator stage, a condenser, the condenser being located after the compressor stage and before the evaporator stage, and a fluid heat transfer device configured to apply water to an external surface of the compressor to cause the compressor to reject heat when the compressor is operating.
These and other aspects and advantages of the exemplary embodiments will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. Moreover, the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. In addition, any suitable size, shape or type of elements or materials could be used.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary appliance incorporating aspects of the disclosed embodiments.

FIG. 2 is a schematic block diagram of one embodiment of a compressor cooling system incorporating aspects of the present disclosure.

FIG. 3 is a schematic block diagram of an exemplary compressor cooling system incorporating aspects of the disclosed embodiments.

FIG. 4 illustrates an exemplary pattern for an outer casing of a compressor incorporating aspects of the disclosed embodiments.

FIG. 5 illustrates a schematic block diagram of compressor cooling system incorporating aspects of the disclosed embodiments.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Referring to FIG. 1, an exemplary household appliance, such as a refrigerator, incorporating aspects of the disclosed embodiments, is generally designated by reference numeral 100. The aspects of the disclosed embodiments are generally directed to a compressor cooling system for a refrigeration appliance such as a refrigerator. Lowering the temperature of the compressor in a refrigerator can lead to improved performance and efficiency of a compressor in a refrigerant based cooling system. By improving the efficiency, certain benefits and advantages can be realized, such as energy and cost savings. Although the aspects of the disclosed embodiments will generally be described with a respect to a household appliance such as a refrigerator, in alternate embodiments the aspects of the present disclosure can be generally applied to any appliance that includes a refrigerant based cooling system, such as for example, a freezer or air conditioning unit.
The exemplary refrigerator 100 shown in FIG. 1 is a multi-compartment refrigerator that includes at least two compartments 104, 106 within a cabinet structure 102. In the embodiment shown in FIG. 1, the compartment 104 comprises a fresh food compartment, while the compartment 106 comprises a freezer compartment. In alternate embodiments, the refrigerator 100 of the present disclosure can include any suitable number of compartments configured in any suitable manner. The refrigerator 100 includes French style doors 108 and 110 for the fresh food compartment 104, and door or drawer 112 for the freezer compartment 106. A divider or mullion 114 separates the fresh food compartment 104 from the freezer compartment 106. In alternate embodiments, the refrigerator 100 can include any suitably styled doors for the refrigerator compartments 104, 106.
FIG. 2 illustrates one embodiment of a cooling system 200 for the refrigerator 100 incorporating aspects of the disclosed embodiments. In one embodiment, the cooling system 200 includes a compressor 202, a condenser 204, an evaporator 206 and a fluid heat transfer device 210.
The compressor 202 is generally configured to compress a low or ambient temperature and low-pressure refrigerant received from the evaporator 206 into a high-temperature and high-pressure gaseous refrigerant. In the example shown in FIG. 2, the condenser 204 is connected to the compressor 202 and is configured to condense the compressed gaseous refrigerant into a liquid refrigerant. The evaporator 206 is connected between the condenser 204 and the compressor 202 and, is generally configured to evaporate the expanded refrigerant, absorb heat and generate cool air. Each of the compressor 202, the condenser 204 and evaporator 206 can be configured in any suitable manner and include other components and connections for providing the general functionalities associated with a refrigerant based cooling system.
The aspects of the disclosed embodiments are generally directed to compressor cooling system that is configured to lower the temperature of the compressor 202 in the refrigerant based cooling system 200. When the compressor 202 is running, the compressor 202 generates heat. It is desirable to reduce the operational temperature of the compressor 202 and improve, among other things, the energy efficiency of the compressor 202. In the embodiment shown in FIG. 2, the fluid heat transfer device 210 is generally configured to lower the temperature of the compressor 202 by wetting the compressor 202 with a fluid such as water or water vapor, generally referred to herein as “water.” A heat convection process causes the compressor 202 to reject heat to the water, thus lowering the temperature of the compressor 202.
As is shown for example in FIG. 3, the compressor 202 includes an outer casing, outer shell or shear 302. The outer casing 302 generally surrounds the working components of the compressor 202. In one embodiment, the outer casing 302 of the compressor 202 is formed or made from a material that is thermally conductive, such as metal or steel, for example. When the compressor 202 is running, the heat that is generated from the working components inside the compressor 202, as well as the heat from the refrigerant operated on within the compressor 202, is generally transferred to the outer casing 302. The heat can then be rejected to the ambient air outside the outer casing 302. However, the amount of heat that can typically be rejected to the ambient air by this process is limited.
In one embodiment, referring to FIG. 3, the fluid heat transfer device 210 is configured to wet the outer casing 302 of the compressor 202 with water by applying water to the outer casing 302 in the form of water drops or a spray. As is shown in FIG. 3, in one embodiment, to apply the water in the form of water drops, water drop applicator 304 can be used. To apply the water in the form of a spray or mist, water spray applicator 306 is used. In alternate embodiments, any suitable applicator can be used to apply the water to the outer casing 302 of the compressor 202 in the desired form.
Referring to FIG. 3, the water used for application to the outer case 302 of the compressor 202 can be delivered or supplied from one or both of a primary water source 316 as well as a secondary water source 318. In one embodiment, the primary water source 316 generally comprises a main water supply, such as that used to supply the water dispensing device 310 or ice maker 308 of the refrigerator 100. The secondary water source 318 generally comprises recycled water that is formed as a byproduct of the operation of the refrigerator 100. For example, defrost drain water that is generated as a result of a defrosting cycle or process in the cooling system 200 can be collected to make up the secondary water source 318. Alternatively, or in addition to, other water or condensation that may form on the interior or exterior surfaces of the cabinet structure 102 can be collected and used to form the secondary water source 318. The use of the secondary water 318 can allow water to be supplied for cooling the compressor 202 in a practical and energy efficient manner.
The flow of water from the primary and secondary sources 316, 318 to each of the applicators 304, 306 can generally be controlled by the use of one or more valves, such as valves 321-325 shown in FIG. 3. Each of the primary and secondary source 316, 318 can be suitably coupled to the fluid heat transfer device 210 by tubing 320 and the valves 321-325, where each source 316, 318 can be individually controlled to provide an appropriate supply of water to the fluid heat transfer device 210. In one embodiment, referring to FIG. 2, the controller 216 can determine and control the opening and closing of each water valve 321-325 for supplying water to the fluid heat transfer device 210. For example, where only water from the primary water source 316 is being utilized, valves 322 and 323 are open, while valve 321 is closed. When the secondary water source 318 is the only utilized fluid source, valve 322 remains closed, while valves 321 and 323 are opened. The aspects of the disclosed embodiments can also utilize a mix of the primary and secondary water sources 316, 318. In this embodiment, one or more of the valves 321-323 can be partially opened or closed to regulate the flow of water from each of the sources 316, 318, as desired. In one embodiment, one of the water valves, such as water valve 323, can also include a pump, or other such water regulator, that is configured to adjust the fluid application rate as is otherwise described herein.
In one embodiment, the control of the water valves 321-323 for feeding the fluid heat transfer device 210 can also be correlated to the operational cycles of the compressor 202. In one embodiment, when the compressor 202 is ON, the water valves 321-323 will be enabled to be opened or open. When the compressor 202 is OFF, the water valves 321-323 can be disabled, or kept closed.
Generally, the amount of water that is used to wet the outer casing 302 will be controlled so that there is a minimal amount of accumulation of excess water in or around the area beneath the compressor 202. In one embodiment, the rate of application of the water or water vapor to the outer casing 302 will generally be a function of the evaporation rate of the water. An approximate temperature of the external surfaces of the outer casing 302 when the compressor is running will be known or can be determined. Based on this temperature, an evaporation rate of the water can be calculated. Generally, the water application rate is equal to or less than the evaporation rate of the water. In one embodiment, the ambient temperature and/or the relative humidity level can also be determined and factored into the calculation of the water evaporation rate.
As is shown in FIG. 2, in one embodiment, the cooling system 200 can also include a temperature sensor 214. The temperature sensor 214 can be configured to monitor one or more of the ambient temperature, or the temperature of the system components such as the compressor 202 or the condenser 204. The temperature sensor 214 can be any suitable temperature sensing device, such as a thermocouple, for example, and can comprise a stand-alone device or be integrated as part of the controller 216, for example. In one embodiment, the temperature sensor 214 can provide temperature indications to the controller 216, where the controller 216 can interpret the data for the purpose of determining whether or not to activate the fluid heat transfer device 210 or to adjust the fluid application rate. For example, if the ambient temperature or the temperature of the outer casing 302 of the compressor 202 is not high enough to provide adequate evaporation of the water, the controller 216 can interrupt, adjust or disable the operation of the fluid heat transfer device 210. As the ambient temperature, or the temperature of the outer casing 302 increases, the fluid application rate can be correspondingly increased.
As is also shown in FIG. 2, in one embodiment, the system 200 includes a humidity sensor 212. The humidity sensor 212 can be integrated into the system 200 or a stand-alone device. The humidity sensor 212 is generally configured to detect a humidity level in and around the appliance 100, and in particular in the area of the compressor 202. The determined humidity level can then be used by the controller 216 to control the water application rate so that most, if not all of the water applied to the outer casing 302 will evaporate. For example, in periods of high humidity, the water application rate can be set to a rate that is lower than the water application rate that is used in drier periods. In one embodiment, the determined humidity level can also be used to control the activation of the fluid heat transfer device 210. If the humidity level is too high, it may not be desirable to introduce or apply any water to the compressor 202. In one embodiment, a signal corresponding to the detected humidity level is sent to the controller 216, where the controller 216 is configured to enable or disable the fluid heat transfer device 210. The aspects of the disclosed embodiments are generally applicable in environments where the relative humidity levels are below pre-determined values, such as for example, approximately 40-50% relative humidity, and are less effective at humidity levels that are higher than approximately 70%. The ranges disclosed herein are merely exemplary and any suitable relative humidity level can be used.
Generally, the external surface 330 of the outer casing 302 of the compressor 202 is relatively smooth, and any water that is applied to the external surface 330 will have a tendency to run over and off of the external surface 330 in an arbitrary manner. In one embodiment, referring to FIG. 4, the external surface or surfaces 330 can be configured to include a pattern 402. The pattern 402 is generally configured to enhance heat exchange and water evaporation. FIG. 4 illustrates an exemplary pattern 402 that can be used in conjunction with the aspects of the disclosed embodiments. The pattern 402 can be patterned or molded with one or more grooves 404. The pattern 402 or grooves 404 are generally configured to more evenly spread and distribute the water, such as water drop 406, over the external surfaces 330 to enhance the heat exchange and evaporate. As is shown in FIG. 4, pattern 402 will cause the water drop 406 to separate into one or more parts and travel in the direction A, as indicated by the arrows. In one embodiment, the pattern 402 is in the form of grooves that can be stamped or molded into the external surfaces 330. In alternate embodiments, the pattern 402 can include any suitable pattern, including for example, a double spiral or quad-spiral pattern.
As noted above, in one embodiment, a pan or container 314 can be used to collect water than runs off of the external surface 330 of the compressor 202. In one embodiment, the pan 314 can include or be coupled to a water level sensor 326. The water level sensor 326 can monitor a water level in the pan 314. If the water level gets to high, the fluid heat transfer device 210 can be disabled, or the flow of water to the fluid heat transfer device 210 can be stopped. In one embodiment, the water level sensor 326 can comprise a float mechanism. In alternate embodiments, the water level sensor 326 can comprise any suitable water level sensor, other than including a float. In one embodiment, any water collected in the pan 314 can be fed back to the fluid heat transfer device 210 through the secondary water source 318. In this manner, any runoff water is recycled.
In one embodiment, referring to FIG. 5, the evaporation rate of the water and cooling effect on the compressor 202 can be enhanced by the use of a fan 502 to move air over and around the compressor 220, when the outer surface 302 are in the wetted state. When the outer casing 302 of the compressor 202 is wetted by the fluid heat transfer device 210, the evaporation removes heat from the outer casing 302 of the compressor 202. The temperature of the outer casing 302, and thus the temperature of the compressor 202, will be lowered by rejecting heat to this water. In the embodiment shown in FIG. 5, the fan 502 is positioned to pull air in the direction F1 over and around the compressor 202. In an alternate embodiment, the fan 502 can be position so as to push a flow of air around and over the outer casing 302. For example, in one embodiment, the fan 502 comprises the fan used to move air through the condenser 204 in a manner generally understood. One example of such a fan configuration is described in U.S. patent application Ser. No. ______ (GE Docket No. 242918), the disclosure of which is incorporated herein by reference in its entirety. In this embodiment, the airflow path F1 generally comprises the airflow path created by the condenser fan. In alternate embodiments, the airflow path can be any suitable airflow that will enhance the evaporation of the water applied to the outer casing 302 of the compressor 220.
The aspects of the disclosed embodiments may also include software and computer programs incorporating the process steps and instructions described above that are executed in one or more computers. In one embodiment, one or more computing devices, such as a computer or controller 216 of FIG. 2, are generally adapted to utilize program storage devices embodying machine-readable program source code, which is adapted to cause the computing devices to perform the method steps of the present disclosure. The program storage devices incorporating features of the present disclosure may be devised, made and used as a component of a machine utilizing optics, magnetic properties and/or electronics to perform the procedures and methods of the present disclosure. In alternate embodiments, the program storage devices may include magnetic media such as a diskette or computer hard drive, which is readable and executable by a computer. In other alternate embodiments, the program storage devices could include optical disks, read-only-memory (“ROM”) floppy disks and semiconductor materials and chips.
The computing devices may also include one or more processors or microprocessors for executing stored programs. The computing device may include a data storage device for the storage of information and data. The computer program or software incorporating the processes and method steps incorporating features of the present disclosure may be stored in one or more computers on an otherwise conventional program storage device.
The aspects of the disclosed embodiments are generally directed to cooling a compressor of a refrigerant based cooling system in a household appliance. A fluid in the form of water or water vapor is applied to the external surfaces or outer casing of the compressor to enhance a heat exchange between the compressor and the ambient air. The fluid is applied in the form of droplets or a spray, and is typically applied at a rate that is equal to or slightly below the evaporation rate of the water. The source of the water that is applied to the compressor can come one or both of a main water supply or a recycled water supply, where the recycled water supply is formed as a byproduct of the operation of the refrigerator as well as any runoff from the application of the water to the compressor. Decreasing the temperature of the compressor in a refrigerator can generally improve the compressor efficiency and lead to certain benefits and advantages, such as energy and cost savings.
Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to the exemplary embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Claims

What is claimed is:

1. A system for cooling a compressor for an appliance, comprising:

a water source;

a compressor having an outer shell, the compressor being configured to compress a refrigerant during a cooling cycle of the appliance; and

a fluid heat transfer device configured to receive water from the water source and apply the water to the outer shell for rejecting heat from the compressor.

2. The system of claim 1, wherein the water source comprises at least one of condensation from the exterior of a case of the appliance, defrost drain water from the appliance and make-up water for the appliance.

3. The system of claim 1, wherein the fluid heat transfer device comprises a tube, one end of the tube receiving a flow of water from the water source and the other end of the tube releasing a flow of water on to the outer shell of the compressor.

4. The system of claim 3, wherein the other end of the tube comprises a drop or spray applicator.

5. The system of claim 1, further comprising a valve coupled between the water source and the fluid heat transfer device, the water valve being configured to enable a flow of water from the water source to the heat transfer device when the compressor is running and to prevent the flow of water when the compressor is not running.

6. The system of claim 1, wherein the outer shell of the compressor further comprises an external surface having a pattern formed in the external surface, the pattern being configured to distribute the water about the external surface to enhance the heat exchange between the outer shell and the water.

7. The system of claim 6, wherein the pattern comprises grooves formed in the external surface of the outer shell.

8. The system of claim 1, wherein the fluid heat transfer device comprises a water misting device configured to receive a flow of water from the water source and apply the received water to the outer shell of the compressor in a form of a mist.

9. The system of claim 1, further comprising a humidity sensor positioned in a area of the compressor and configured to detect an ambient humidity level in the area of the compressor, the humidity sensor being further configured to enable the fluid heat transfer device to apply water to the outer shell of the compressor when the detected ambient humidity level is less than a pre-determined humidity level.

10. A method comprising:

detecting an operation of a compressor in a refrigerant-based cooling appliance; and

applying water to an external surface of the compressor at a rate configured to enhance an evaporation of the water and enable the compressor to reject heat.

11. The method of claim 10, wherein the rate at which water is applied to the external surface of the compressor is less than or equal to an evaporation rate of the water.

12. The method of claim 11, wherein the evaporation rate of the water is determined as a function of an ambient temperature and ambient humidity level detected around the appliance.

13. The method of claim 10, further comprising applying the water to a pattern formed in the external surface of the compressor.

14. The method of claim 10, further comprising applying an airflow path over and around the compressor while the compressor is operating.

15. The method of claim 10, further comprising receiving the water applied to the external surface of the compressor from at least one of condensation from the exterior of a case of the appliance, defrost drain water from the appliance and make-up water for the appliance.

16. A cooling system for a household appliance, comprising:

an evaporator;

a compressor coupled to the evaporator,

a condenser located after the compressor and before the evaporator; and

a fluid heat transfer device configured to apply water to an external surface of the compressor to cause the compressor to reject heat when the compressor is operating.

17. The cooling system of claim 16, wherein the fluid heat transfer device comprises a water applicator and a connection to a water source, the fluid heat transfer device being configured to apply the water in a form of drops or a spray to an external surface of the compressor.

18. The cooling system of claim 17, wherein the water is in the form of a liquid or vapor.

19. The cooling system of claim 18, wherein the fluid dispensing device receives the water from a defrost water supply and a make-up water supply.

20. The cooling system of claim 17, wherein the external surfaces of the compressor comprise a pattern, the pattern being in the form of a set of grooves in the external surface, the pattern being configured to enhance heat exchange and evaporation of the water.