Variable Displacement Compressor

摘要

Variable displacement compressor, with center bore 101b in a center part of cylinder block 101, includes: first bore 101b1 supporting plain bearing 131 of drive shaft 110; second bore 101b2 with a peripheral wall radially outside of first bore 101b1; and third bore 101b3 connected to a crank chamber and radially outside of a first bore 101b1. A pressure supply path 145 for flowing a part of a discharge refrigerant from a discharge chamber to the crank chamber includes: second bore 101b2; a first path 145a communicating second bore 101b2 with the discharge chamber; a second path 145b that communicates with second bore 101b2, and axially extends from one end surface of drive shaft 110 toward the inside of drive shaft 110; and a third path 145c substantially orthogonal to second path 145b and opens to an outer peripheral surface of drive shaft 110, and communicates with the crank chamber.

主权项

1. A variable displacement compressor comprising:
a cylinder block in which a plurality of cylinder bores arranged annually and a center bore positioned within the plurality of cylinder bores are formed; a front housing that blocks one end of the cylinder block, and defines a crank chamber together with the cylinder block; a valve plate that blocks the other end of the cylinder block, and in which a discharge hole and a suction hole communicating with each of the plurality of cylinder bores are formed; a cylinder head that is provided opposite to the cylinder block with the valve plate in between, and in which one of a suction chamber and a discharge chamber is formed in a center part and the other one of the suction chamber and the discharge chamber is formed in an annular part outside the center part, the suction chamber communicating with a suction-side external refrigerant circuit, and the discharge chamber communicating with a discharge-side external refrigerant circuit; a piston that is disposed in each of the plurality of cylinder bores, and reciprocates in an axial direction of a drive shaft; the drive shaft one end of which is inserted into the center bore, and that is radially supported by the cylinder block via a plain bearing; a rotor that is fixed to the drive shaft, and rotates integrally with the drive shaft; a swash plate that is connected to the rotor via a connecting unit, and slidably attached to the drive shaft so that the swash plate has a variable inclination angle with respect to an axis of the drive shaft when rotating synchronously with the rotor; a conversion mechanism that converts rotation of the swash plate into reciprocation of the piston; a pressure supply path that communicates between the discharge chamber and the crank chamber; a control valve that adjusts an opening of the pressure supply path; and a pressure release path that communicates between the crank chamber and the suction chamber, wherein a pressure in the crank chamber is changed by adjusting the opening by the control valve to change the inclination angle of the swash plate and adjust a stroke of the piston, and a refrigerant sucked into the cylinder bore from the suction chamber is compressed and discharged into the discharge chamber, and wherein a downstream part of the pressure supply path includes: an upstream path along a center axis in the drive shaft; and a downstream path intersecting and connecting to the upstream path, and having an open end communicating with the crank chamber.