Control Valve For A Variable Displacement Compressor

摘要

A control valve is configured such that a suction pressure, which is used to displace a sub-valve element in a valve opening direction after a main valve has been closed, is varied according to a value of current supplied to a solenoid. A crankcase communication port, which communicates with a crankcase of a compressor, and a suction chamber communication port, which communicates with a suction chamber of the compressor, are provided in a body. A sub-valve chamber whose diameter is larger than that of the main valve hole is formed between the crankcase communication port and a main valve hole, and a sub-valve is placed in the sub-valve chamber.

主权项

1. A control valve for a variable displacement compressor for varying a discharging capacity of the compressor for compressing refrigerant led into a suction chamber and discharging the compressed refrigerant from a discharge chamber, by regulating a flow rate of the refrigerant led into a crankcase from the discharge chamber, the control valve comprising:
a body having:
a discharge chamber communication port that communicates with the discharge chamber;a crankcase communication port that communicates with the crankcase;a suction chamber communication port that communicates with the suction chamber;a main passage that communicates between the discharge chamber communication port and the crankcase communication port, the main passage having a main valve hole; anda sub-passage that communicates between the crankcase communication port and the suction chamber communication port; a main valve seat provided in an opening end of the main valve hole; a main valve element configured to open and close a main valve by touching and leaving the main valve seat, the main valve element being slidably supported by a guiding passage formed in the body; a power element configured to supply a drive force in a valve opening direction to the main valve element according to a displacement amount of a pressure-sensing member, the power element including the pressure-sensing member for sensing a predetermined pressure-to-be-sensed and developing a displacement in an opening or closing direction of the main valve; a solenoid configured to generate a force opposing the drive force of the power element when the solenoid electrically conducts; an actuating rod configured to transmit a force generated by the solenoid to the power element, the actuating rod being coupled with the solenoid; a sub-valve seat provided in the sub-passage; and a sub-valve element configured to open and close a sub-valve by touching and leaving the sub-valve seat, wherein the pressure-to-be-sensed, which is used to displace the sub-valve element in a valve opening direction after the main valve has been closed, is varied according to a value of current supplied to the solenoid, and wherein a sub-valve chamber whose diameter is larger than that of the main valve hole is formed between the crankcase communication port and the main valve hole, and the sub-valve is placed in the sub-valve chamber.