Pressure pulsations reducing compressor

Abstract

In a variable displacement compressor of the invention, cylinder bores (111) and a crankcase (121) are formed in a housing, single-ended pistons (37) are fitted in the cylinder bores (111), and a cam plate (23) is provided in the crankcase (121). The displacement capacity of the compressor is varied by controlling the angle of inclination of the cam plate (23) in accordance with the difference between the internal pressure of the crankcase (121) and an suction pressure present on both sides of each single-ended piston (37). A dampening or muffler chamber (65) is provided downstream of an output channel (114) through which a refrigerant gas discharged from the cylinder bores (111) passes. A check valve (69) which opens and closes in accordance with a pressure difference between upstream and downstream sides of the output channel (114) is provided in the output channel (114), upstream of the muffler chamber (65). The present invention reduces the effects of pressure pulsations caused by the compression motion of the compressor and caused by the valve body of the open/close device hunting, has no bad effects on the external refrigerant circuit connected to the compressor, and increases the reliability of the lip seal.