PURPOSE: To certainly control the capacity of a vane type rotary compressor by installing an opening/closing valve operated according to the load and a check valve between a bypass inlet hole communicating between a condenser and an expansion valve and a bypass outlet hole communicating to the inside of a working chamber.
CONSTITUTION: When a solenoid valve is excited, a bypass inlet hole 21 for the communication between a condenser and an expansion valve communicates to a bypass outlet hole 22 which communicates to the second suction chamber 31, through a check valve 33. Therefore, the high pressure gas filling the part between the condenser and the expansion valve flows into the second suction chamber 31, and expands again, and accelerates the revolution of a rotor, and reduces the driving torque of the compressor. In this case, the pressure in the second suction chamber 31 rises to the suction pressure, and even if said pressure is increased by the pressure in the working chamber 33, the flow of gas into the working chamber 33 from the second suction chamber 31 is prevented by the action of a check valve 32. Therefore, the gas in the working chamber 33 can be bypassed certainly.