Swashplate type variable-displacement compressor

Abstract

A swashplate type variable-displacement compressor includes a compressor housing defining therein a crank chamber, a refrigerant suction chamber, a refrigerant discharge chamber, and a low-pressure refrigerant passage connected to an evaporator outlet, and a pressure regulator. The pressure regulator controls the amount of low-pressure refrigerant gas flowing into the refrigerant suction chamber by regulating a differential pressure between the pressure in the refrigerant suction chamber and the pressure in the crank chamber. The pressure regulator is comprised of a flow control valve including a first spring-loaded, normally-closed spool valve and a pressure chamber accumulating the working pressure used to force the spool valve toward its fully-opened position, and a flow control valve actuating mechanism including a communication passage through which the refrigerant discharge chamber is communicated with the pressure chamber, a second spring-loaded, normally-closed pilot valve provided in the communication passage, and an electromagnetic solenoid controlling the opening of the pilot valve so that the opening increases with an increase in exciting current supplied to the solenoid. The pilot valve serves to introduce high-pressure refrigerant gas in the refrigerant discharge chamber into the pressure chamber as the working pressure with the opening controlled by the solenoid.