A variable capacity compressor includes a compression chamber that compresses a working fluid, an inlet chamber to house the working fluid to be compressed, a discharge chamber to house the working fluid compressed in the compression chamber and discharged therefrom, a control pressure chamber to house a swash plate rotating in accordance with a rotation of the drive shaft, a supply passage to facilitate communication between the discharge chamber and the control pressure chamber, a bleed passage to facilitate communication between the control pressure chamber and the inlet chamber, a first control valve including a first valve portion to adjust an opening degree of the supply passage, a second control valve provided on the bleed passage and including a spool housing recess formed on the bleed passage, and a back pressure chamber between the spool and a bottom of the spool housing recess.

A control valve of a variable displacement compressor capable of preventing a decrease in control accuracy is provided. In a control valve 300, a valve chamber 321b accommodating a valve body 322 constitutes a part of a pressure supply passage for supplying refrigerant in a discharge chamber to a crank chamber, or constitutes a part of a pressure relief passage through which refrigerant in the crank chamber flows toward a suction chamber, depending on whether the valve hole 321c is open or closed by a valve portion 322a of the valve body 322. A partition portion 322b having a larger diameter than that of the valve portion 322a of the valve body 322, partitions the valve chamber 321b into a first pressure application chamber 321b1 on which the pressure in the suction chamber mainly acts, and a second pressure application chamber 321b2 on which the pressure in the crank chamber mainly acts and into which refrigerant in the discharge chamber flows when the valve hole 321c is open. A clearance between an outer peripheral surface of the partition portion 322b and an inner peripheral surface of the valve chamber 321b forms a fixed orifice of the pressure relief passage. The second pressure application chamber 321b2 is formed to have a larger inner diameter than that of the inner peripheral surface of the valve chamber 321b.

A variable displacement compressor which prevents leakage of a refrigerant flowing directly into a suction chamber without passing via a crank chamber at a time of a minimum discharge displacement operation, thus making it possible to prevent an increase of a minimum discharge displacement by increasing a refrigerant pressure in the crank chamber, and in addition, making it possible to prevent insufficient lubrication of sliding portions and the like in the crank chamber.

A variable displacement compressor includes a control valve and a check valve. The control valve is in fluidic communication with a discharge chamber of the compressor and a crankcase of the compressor. The check valve is interposed between the control valve and the discharge chamber. The check valve is configured to allow flow from the discharge chamber to the control valve and to prevent flow from the control valve to the discharge chamber. The check valve includes a ball and a spring. The spring is configured to urge the ball toward a closed position. The spring is characterized by a rate of the spring and a free-length of the spring, and the rate and the free-length are selected to minimize de-stroke noise caused by a rapid change of the compressor operation to a low displacement state.

[Object] To provide a variable capacity compressor configured to achieve an enhancement of an activation performance of a compressor and reduce an amount of internally circulating refrigerant during an intermediate stroke in a simple structure.

[Solving Means] A supply passage 40 configured to cause a discharge chamber 34 and a control pressure chamber 4 to communicate with each other; a first bleed passage 42 configured to cause the control pressure chamber 4 and an inlet chamber 33 to communicate with each other; a first control valve 50 configured to adjust an opening degree of the supply passage 40; and a second control valve 45 provided on the first bleed passage 42 are provided, and the second control valve 45 includes: a spool 47 housed in a spool housing recess formed on a bleed passage and configured to open and close the first bleed passage 42, a back pressure chamber 48 formed behind the spool 47, and biasing means (compression spring 49) configured to bias the spool 47 in a direction of opening the first bleed passage 42. The back pressure chamber 48 of the second control valve 45 is selectively connected to the discharge chamber 34 or the inlet chamber 33 via the first control valve 50.

A variable-capacity compressor capable of improving starting performance of the compressor and eliminating the risk of the compressor becoming uncontrollable due to contamination or the like in a refrigerant is disclosed. An opening passage allowing the control pressure chamber to communicate with a suction chamber is provided separately from a bleed passage, a valve housing chamber is formed on the opening passage, and the opening passage is formed by including an upstream-side opening passage allowing the control pressure chamber to communicate with the valve housing chamber and a downstream-side opening passage allowing the valve housing chamber to communicate with the suction chamber. A valve body housed so as to open/close the downstream-side opening passage and a biasing means biasing the valve body in an opening direction are provided. The valve housing chamber is connected to the downstream side of a pressure control valve provided on a supply passage.