Displacement control valve

1. A displacement control valve modulating a fluid flow or fluid pressure within control chamber by means of controlling the opening degree of valve portion, said displacement control valve comprising;

a valve main body having a first valve chamber, a second valve chamber and a third valve chamber, said first valve chamber communicating with a first communication passage for permitting fluid at control pressure to flow therethrough, said second valve chamber having a second valve seat face for a valve hole communicating with said first valve chamber, said second valve chamber communicating with a second communication passage for permitting fluid at discharge pressure to flow therethrough, said third valve chamber having a third valve seat face, said third valve chamber communicating with a third communication chamber for permitting fluid at suction pressure to flow therethrough;

a valve body being disposed within said valve main body and having a first valve member, a second valve member and a third valve member, said second valve member having an intermediate communication passage therein communicating with said first valve chamber and said third communication passage, said second valve member opening or closing a valve hole with respect to said second valve seat face, thereby communicating with said first valve chamber and said second valve chamber, said third valve member performing a valve opening/closing action with respect to said third valve seat face in an reverse synchronous manner against said second valve member, thereby opening or closing the communication with said intermediate communication passage and said third communication passage, said first valve member being disposed in said first valve chamber and performing a valve opening/closing action in the same direction in a synchronous manner to said second valve member;

a pressure sensing member being disposed within said first valve chamber, said pressure sensing member having a valve seat portion, said valve seat portion being disposed at a free end of said pressure sensing member, said free end performing an expanding or contracting action in accordance with suction pressure, said valve seat portion performing a valve opening/closing action with respect to said first valve member, thereby opening or closing the communication with said first valve chamber and said intermediate communication passage; and

a solenoid member being installed in said valve main body, said solenoid member driving said valve body for opening or closing the respective valves of said valve body in accordance with an electric current supplied thereto;

wherein an auxiliary communication passage is disposed in said valve body and/or said valve seat portion within said first valve chamber, said auxiliary communication passage providing a communication between said first valve chamber and said intermediate communication passage.

2. A displacement control valve according to claim 1 , wherein the diameter of said auxiliary communication passage is set in a range of from 0.8 mm to 2 mm.