Patent ID: 6126405
Filing Date: 2000-10-03
Classification: F04B

Abstract:
A compressor having a drive plate located in a crank chamber and tiltably mounted on a drive shaft and a piston operably coupled to the drive plate and located in a cylinder bore, wherein said drive plate converts rotation of the drive shaft to reciprocating movement of the piston in the cylinder bore, said piston compressing gas supplied to the cylinder bore from an external circuit by way of a suction chamber and discharging the compressed gas to the external circuit by way of a discharge chamber, wherein the inclination of the drive plate is variable according to a difference between the pressure in the crank chamber and the pressure in the cylinder bore, said piston moving by a stroke based on the inclination of the drive plate to control the displacement of the compressor, said compressor comprising:means for adjusting the pressure in one of the crank chamber and the suction chamber to vary the difference between the pressure in the crank chamber and the pressure in the cylinder bore, wherein said adjusting means includes a gas passage for passing the gas used for adjusting the pressure and a control valve for adjusting the amount of the gas flowing in the gas passage;wherein said control valve includesa valve body for adjusting the opening size of said gas passage, said valve body being movable in the first direction and in a second direction opposite to a first direction, wherein said valve body moves in the first direction to open the gas passage and moves in the second direction to close the gas passage,a reacting member for reacting to the pressure of the gas supplied to the compressor from the external circuit, wherein said reacting member moves the valve body in accordance with the pressure of the gas supplied to the compressor from the external circuit, anda solenoid for biasing the valve body in one of the first direction and the second direction with a force based on a value of electric current supplied to the solenoid; andmeans for supplying undulating current to the solenoid, wherein said supplying means varies the average value of the undulating current to vary the biasing force of the solenoid.