VARIABLE CAPACITY POSITIVE DISPLACEMENT TYPE COMPRESSORS

摘要

A reciprocating piston swash plate refrigerant compressor is disclosed having a variable pumping capacity control arrangement wherein the pumping capacity is varied by effecting communication between the compressor's suction side and one or more of the cylinders during compression. Such communication is provided by a bypass valve controlling an additional suction port formed in the head end of the cylinder in parallel with the normal valve controlled suction port therefor. The bypass valve is urged to open the bypass port by cylinder pressure acting directly and continuously on a small pressure responsive area thereof and is urged to close the bypass port by discharge pressure delivered to act on a large pressure responsive area thereof under the control of a separate control valve which alternatively communicates suction side pressure with the large pressure responsive area when it is desired to permit the bypass valve to be opened by the cylinder pressure.