Variable displacement swash plate type compressor

Abstract

A variable displacement swash plate type compressor comprises a suction chamber, a discharge chamber and a crank chamber. A flow rate control valve mechanism is provided along a refrigerant supply passage, which connects the discharge chamber to the crank chamber. The flow rate control valve mechanism is provided with a discharge pressure chamber and an intermediate chamber. A valve hole is provided between the discharge pressure chamber and the intermediate chamber, to permit both chambers to communicate with each other. A pressure sensitive member is provided in the intermediate chamber to separate the intermediate chamber into a first and a second pressure sensitive chambers. The first pressure sensitive chamber communicates with the discharge pressure chamber via the valve hole. The second pressure sensitive chamber communicates with either the crank chamber or the suction chamber. The pressure sensitive member is displaceable as a function of the pressure difference between the first and second pressure sensitive chambers. A restriction permits the first pressure sensitive chamber and the crank chamber to communicate with each other. A valve body is coupled to the pressure sensitive member to be displaceable in synchrony with the action of the pressure sensitive member, and regulates the opening of the valve hole according to the displacement. A return member biases the valve body and the pressure sensitive member to a valve open position when the pressure in the discharge chamber becomes almost zero.