Patent ID: 8439652

Claim:
A suction throttle valve of a variable displacement compressor having a compressor housing including a suction chamber and a crank chamber comprising: an inlet through which suction refrigerant gas is drawn into the compressor; a suction passage connecting the inlet to the suction chamber; a first valve body for adjusting an opening area of the suction passage, the first valve body being movably arranged in the suction passage; a valve housing accommodating the first valve body, wherein the valve housing has a circumferential wall formed with a communication port opened to the suction passage; a second valve body accommodated in the valve housing; an urging member urging the first valve body in the direction that decreases the opening area of the suction passage, the urging member provided between the first valve body and the second valve body; a valve chamber formed in the valve housing on an opposite side of the first valve body with respect to the suction passage, the valve chamber is defined by the first valve body, the second valve body, and a part of the circumferential wall of the valve housing along which the first valve body is slidably guided; and a stop provided between the first valve body and the second valve body to restrict a movement of the second valve body; a communication hole formed in the circumferential wall of the valve housing on an opposite side of the stop from the communication port, wherein the communication hole connects the suction chamber to the valve chamber, wherein an opening area of the communication hole is variable in accordance with the movement of the second valve body so that the opening area of the communication hole becomes maximum during the maximum displacement operation of the compressor and the opening area of the communication hole becomes reduced during the intermediate displacement operation of the compressor.