Rotary expansible chamber devices – Working member has planetary or planetating movement – Helical working member – e.g. – scroll
Reexamination Certificate
1999-05-10
2001-02-13
Denion, Thomas (Department: 3748)
Rotary expansible chamber devices
Working member has planetary or planetating movement
Helical working member, e.g., scroll
C418S055600, C418S270000, C418SDIG001
Reexamination Certificate
active
06186753
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to apparatuses for minimizing oil leakage during reverse running of scroll compressors.
Scroll compressors include compressors mounted within a sealed housing structure. The sealed housing structure receives a compressor pump unit and an electric motor for driving the compressor pump unit. Refrigerant and oil are allowed to flow within the compressor housing to perform various functions such as cooling the motor, etc.
Scroll compressors are designed to operate in one direction. Gas enters the housing via a suction tube. The gas flows into compression chambers in the compressor where it is compressed and discharged via an outlet tube. If the power input lines leading from a power supply to the motor are misconnected, however, an improper phasing of the voltage may be supplied and the motor may run in reverse. In this situation, gas is being pumped from the outlet tube toward the suction tube.
During this reverse running mode, oil mixed with gas may be pumped out of the suction tube. This is undesirable, as the compressor could soon run low on oil.
Scroll compressors are typically one of two types. In a “high side” compressor, the housing section which encloses the motor is at a high pressure. The section receives compressed gas from the outlet tube. In this type compressor, the suction tube is connected directly into the scroll pump unit. Check valves have been placed on high side suction tubes.
In a “low side” compressor, the suction tube communicates with the housing portion that encloses the motor. Check valves have not been placed on the suction tube in “low side” compressors.
SUMMARY OF THE INVENTION
It is an object of the present invention to minimize the amount of oil that is pumped out of a scroll compressor during reverse running.
In carrying out the above object, and other objects, features and advantages of the present invention an apparatus is provided for minimizing oil leakage during reverse running of a scroll compressor. The scroll compressor includes means for preventing oil from draining out of the suction tube during reverse running of the compressor.
In a first embodiment of the present invention the means for preventing oil leakage is a check valve disposed at the suction tube. The valve has a spring biasing the valve to close the suction tube, and prevent refrigerant and oil from exiting the suction tube during reverse running of the compressor.
Preferably, the check valve has a stem portion and a land portion. The spring circles the stem portion and rests on the land portion. The land portion lies adjacent the suction tube, and selectively closes the tube. A baffle plate is mounted in the compressor housing, and has side walls extending inwardly from an inside surface of the compressor housing and a rear wall extending between the side walls. The baffle plate further includes an opening receiving the check valve stem portion and providing a reaction surface for the spring.
In a second embodiment of the present invention, the means for preventing oil leakage during reverse running is an oil dam that extends longitudinally above the suction tube on an inner wall of the compressor housing and bends circumferentially with the inner wall. The oil dam separates entrained oil from the refrigerant. Preferably, the dam is structured to drain oil axially along the inner wall away from the suction tube. The oil dam preferably includes an upper end and a lower end, with the upper end extending radially inwardly from the inner surface and the lower end attached to the inner housing surface.
REFERENCES:
patent: 4545747 (1985-10-01), Tamura et al.
patent: 5496160 (1996-03-01), Richardson, Jr., et al.
patent: 5533875 (1996-07-01), Crum, et al.
patent: 60-101296 (1985-06-01), None
patent: 0177481 (1989-07-01), None
patent: 0005787 (1990-01-01), None
patent: 0043691 (1991-02-01), None
patent: 3-096679 (1991-04-01), None
patent: 58200019 (1992-11-01), None
patent: 404330393 (1992-11-01), None
patent: 5302579 (1993-11-01), None
patent: 6-272678 (1994-09-01), None
Barito Thomas R.
Hugenroth Jason J.
Carlson & Gaskey & Olds
Denion Thomas
Scroll Technologies
Trieu Theresa
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