TEMPERATURE PROTECTION SWITCH BIASED AGAINST SCROLL COMPRESSOR SHELL
A sealed compressor is provided with a temperature sensor biased against an outer surface of its shell. By biasing the temperature sensor against the shell, good contact between the temperature sensor and the shell is ensured. Also by use of molded material around the senor, the sensor is insulated from ambient air, increasing the accuracy of the sensor.
This application relates to a temperature protection switch which senses an unduly high temperature, and operates to stop operation of a compressor motor, and wherein the switch is biased against an outer surface of the compressor shell.
Refrigerant compressors are used in refrigerant systems. In a typical refrigerant compressor, a compressor pump unit and its motor are mounted within a hermetically sealed shell. Typically, suction refrigerant is directed into this shell, and serves to pass over a compressor motor, cooling the motor.
Various problems can occur during the operation of a refrigerant compressor. One often experienced problem is a loss of charge situation. In such situations, the amount of refrigerant within the refrigerant system is reduced, such as by a leak. When this occurs, there may be insufficient refrigerant to cool the motor. Other problems can occur, and can result in unduly high temperatures within the compressor. It is desirable to sense these unduly high temperatures accurately, and stop operation of the compressor motor when they occur. Thus, various methods have been provided in refrigerant compressors to sense unduly high temperatures. One known sensor is fixed to an outer surface of the refrigerant compressor housing shell. However, there have been some challenges in maintaining this sensor attached securely to the outer shell.
SUMMARY OF THE INVENTIONIn a disclosed embodiment of this invention, a temperature sensor for a refrigerant compressor is biased against an outer surface of the compressor shell. In this manner, continuous good contact between the temperature sensor and the compressor shell is ensured. Additionally, use of a molded material around the sensor serves to insulate it from ambient air circulating around the sensor, thus increasing the sensing accuracy.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
A compressor 20 is illustrated in
The compressor as described at this point is as known in the art. As mentioned above, for several reasons, it is desirable to monitor the temperature within the compressor, and stop operation should the compressor temperature become unduly high. Thus, temperature sensor 34, which may be any type of known temperature sensor, is incorporated onto the upper surface of the housing upper shell 30. A molded plug 36 has ears 42 which snap into openings 40 in a fence 38. Fence 38 is welded to the upper surface of the upper shell 30. The molded plug serves to bias the temperature sensor 34 against the upper shell, and thus ensure good contact, in addition to insulating the sensor from the lower temperature ambient air.
Should the sensor 34 sense that the temperature within the compressor is unduly high, a signal is sent to a controller 44, which stops operation of the motor 22.
The molded plug is preferably molded of a suitable plastic, which will have the required resilience to bias the temperature sensor against the upper shell.
Claims
1. A sealed compressor comprising:
- a compressor pump unit and an electric motor;
- a housing shell sealing said compressor pump unit and said motor; and
- a temperature sensor attached to an outer surface of said housing shell, and a bias force holding said temperature sensor against said outer surface.
2. The compressor as set forth in claim 1, wherein said temperature sensor is biased against the outer surface by a molded component.
3. The compressor as set forth in claim 2, wherein said molded component is held within a rigid structure which is fixed to the outer surface.
4. The compressor as set forth in claim 3, wherein said housing shell includes a center shell and an upper shell, and wherein said temperature sensor is in contact with said upper shell.
5. The compressor as set forth in claim 3, wherein said molded component is formed of a resilient material and snaps into openings in said structure.
6. The compressor as set forth in claim 1, wherein said compressor pump unit is a scroll compressor.
7. The compressor as set forth in claim 1, wherein said temperature sensor communicates with a control for selectively stopping operation of the electric motor.
Type: Application
Filed: Jul 31, 2008
Publication Date: Feb 4, 2010
Inventor: Gregory W. Hahn (Arkadelphia, AR)
Application Number: 12/183,163
International Classification: F04B 35/04 (20060101); F04B 49/00 (20060101);