Variable capacity type compressor

Abstract

A variable capacity type compressor in which a control element is mounted in one of side blocks formed with inlet ports for rotation about its own axis in opposite circumferential directions between a first extreme position providing the maximum capacity of the compressor, and a second extreme position providing the minimum capacity of the compressor, to vary the compression starting timing. The control element has cut-out portions through which compression medium is drawn into compression spaces, of which one upstream end with respect to the direction of rotor rotation determines the compression starting timing in cooperation with vanes passing same. The cut-out portion is formed of first and second portions circumferentially arranged. At least one recess is formed in an end face of the cam ring facing the control element, which opens in the camming inner peripheral surface thereof and circumferentially extends from a circumferential location at which a suction stroke is started in a compression space within the cylinder or from a point proximate thereto, toward a downstream side with respect to the direction of rotor rotation. The recess is disposed such that when the control element is in the second extreme position, the recess has a downstream end thereof with respect to the direction of rotor rotation positioned downstream of another end of the cut-out portion. The cut-out portion may further be formed with a third portion circumferentially extending continuously from the second portion toward an upstream side with respect to the direction of rotor rotation.