Abstract: A swash plate type compressor that has a pair of shoes between a swash plate and a piston. The motion of the swash plate is transmitted to the piston through the shoes. Each piston reciprocates according to the transmitted monitor. A coating is applied to each surface of the swash plate to contact the corresponding shoe. The surface of each coating is flat. Each shoe includes a substantially flat surface, which contacts the swash plate, and semi-spherical portion, which is fitted to the piston. Each substantially flat surface includes a main chamfered portion near the periphery. The inclination angle of each main chamfered portion will respect to the corresponding coating in a predetermined angle or less. Each coating contacts one of the substantially flat surfaces. The maximum distance between each main chamfered portion and the corresponding coating is equal to or less than the thickness of the corresponding coating.

Abstract: A variable displacement compressor has a control valve for controlling the displacement of the compressor. When the pressure in a discharge chamber of the compressor (discharge pressure) is equal to or higher than a first threshold value, a controller sets a duty ratio, which is sent to the control valve, to zero % to limit the discharge pressure. As a result, the compressor displacement is minimized and the discharge pressure is lowered. Therefore, the pipes of an external refrigerant circuit does not receive excessive load based on high discharge pressure. When the displacement of the compressor is minimized, circulation of refrigerant in the refrigerant circuit is stopped and refrigerant containing lubricant circulates within the compressor.

Abstract: A variable displacement compressor has a control valve for controlling the displacement of the compressor. When the pressure in a discharge chamber of the compressor (discharge pressure) is equal to or higher than a first threshold value, a controller executes a limiting control for limiting the discharge pressure. During the limiting control, the controller gradually decreases a duty ratio, which is sent to the control valve, such that the displacement of the compressor is gradually decreased. When the duty ratio is decreased to a reference duty ratio, the controller sets the duty ratio to zero %. As a result, the compressor displacement is minimized and the discharge pressure is lowered. Therefore, the pipes of an external refrigerant circuit does not receive excessive load based on high discharge pressure.

Abstract: A piston type compressor includes a housing, which defines a crank chamber. A valve plate forms a part of the housing. A drive shaft is located in the crank chamber. A contact member is plastically deformed and press fitted to the drive shaft. An inner wall and a first sub-plate are located in the housing and limit the axial movement of the drive shaft, respectively. After the contact member is attached to the drive shaft, the axial load required to change the position of the contact member is greater than the maximum axial load applied to the drive shaft due to the increase of the pressure in the crank chamber, and less than the load applied to the contact member by the first sub-plate in accordance with the difference in the thermal expansion coefficient of the housing and the drive shaft.

Abstract: Pistons are accommodated in each cylinder bores of a variable displacement compressor. A swash plate is coupled to the piston for converting rotation of the drive shaft to reciprocation of the pistons. A thrust bearing located between a rotor and a housing of the compressor. The outermost load-bearing points of the thrust bearing are radially farther from the axis of the drive shaft than the axes of the pistons. This permits the thrust bearing to directly receive a reaction forces from the pistons through the rotor without applying a moment to the bearing.

Abstract: A variable displacement compressor compresses gas supplied from an evaporator of an external refrigerant circuit and discharges the compressed gas to the refrigerant circuit. A check valve is located between the compressor suction chamber and the evaporator. The check valve prevents gas flow from the suction chamber to the evaporator. When the compressor is stopped, a displacement control valve increases the pressure in a crank chamber of the compressor to move a swash plate to a minimum inclination position. The pressure in the suction chamber is increased by gas supplied from the crank chamber. Closing the check valve accelerates a pressure increase in the suction chamber. When the pressure in the suction chamber is increased, the control valve limits a further pressure increase in the crank chamber. As a result, the force that decreases the inclination of the swash plate is limited.

Abstract: A variable displacement compressor includes a housing having a suction chamber. A crank chamber is defined in the housing. A valve plate assembly is located in the housing. A drive shaft is supported in the housing. A radial bearing is located in the housing. A holding bore houses the rear end of the drive shaft and the radial bearing. The holding bore is connected to a holding space. A passage connects the holding space and the suction chamber. A restricting member is located in the holding space. The restricting member restricts axial movement of the drive shaft and divides the holding space into a first region and a second region. A clearance is formed between the restricting member and the valve plate assembly. The clearance disappears when the pressure of the crank chamber is increased rapidly.

Abstract: A housing includes a crank chamber and cylinder bores. Pistons are accommodated in the cylinder bores. A drive shaft is supported by the housing to pass through the crank chamber. A lug plate is fixed to the drive shaft. The pistons are coupled to the lug plate, which converts rotation of the drive shaft into reciprocation of the pistons and compresses gas in the cylinder bores. A thrust bearing is located between the housing and the lug plate and transmits a thrust load applied to the lug plate. The thrust bearing includes a front race located next to the housing, a rear race located next to the lug plate, and rollers located between the front and rear races. A front seat for supporting the front race is formed on the housing. A rear seat for supporting the rear race is formed on the lug plate. The diameters of the front and rear seats are different, which causes elastic deformation of the races when a thrust load is applied.

Abstract: In a variable displacement compressor that draws, compresses, and discharges refrigerant gas, the displacement is adjusted by varying the inclination of a cam plate in accordance with the difference between the pressure in a crank chamber and the pressure in cylinder bores. A pressurizing passage connects the crank chamber to a discharge passage. A bleed passage connects the crank chamber to a suction chamber. A displacement control valve is externally controlled and varies the pressure in the crank chamber by adjusting the opening size of either the pressurizing passage or the bleed passage. A suction control valve closes a duct between the suction chamber and an evaporator when the pressure in the crank chamber exceeds a predetermined level to prevent an excessively high pressure in the crank chamber.

Abstract: A variable displacement type swash plate compressor that prevents a drive shaft from moving axially when the difference between a crank chamber pressure and a cylinder bore pressure becomes excessive. A hinge mechanism has a support arm extending from a lug plate and a guide pin extends from a swash plate. The head portion of the guide pin fits in a guide hole formed in the support arm. A cutaway surface is formed in a part of the support arm that defines the guide hole. The cutaway surface forms a clearance in the hinge. The clearance permits the swash plate to move without pulling the drive shaft.

Abstract: A variable capacity type compressor has a tiltable swash plate and pistons. A control valve is arranged to change the pressure in the crank chamber, to vary the capacity of the compressor by changing the inclination angle of the swash plate by changing the pressure in the crank chamber. The control valve has independently movable first and second plungers and a coil arranged around the first and second plungers so that the coil generates an electromagnetic attraction force acting on and between the first and second plungers. First and second valve elements provided on the first and second plungers can adjust the degree of opening of the first and second fluid passages.

Abstract: A variable displacement compressor includes a swash plate and a displacement control valve. The swash plate is moved between a maximum inclination position and a minimum inclination position in accordance with the pressure in a crank chamber. The control valve changes the crank chamber pressure to change the swash plate inclination. The control valve includes a valve body and an electromagnetic actuator for moving the valve body. Movement of the valve body is controlled according to current supplied to the actuator. The control valve also includes a fluid damper for applying fluid resistance to the valve body. The fluid resistance prevents the valve body from moving too quickly. The fluid damper therefore prevents the crank chamber pressure from being suddenly changed. Also, the fluid damper prevents the swash plate inclination from being suddenly changed. Instead of using the fluid damper, the sudden movement of the valve body may be prevented by controlling current supplied to the electromagnetic actuator.

Abstract: A compressor has a cam plate located in a crank chamber and mounted on a drive shaft and a piston coupled to the cam plate and located in a cylinder bore. The piston compresses gas supplied to the cylinder bore from a separate external circuit by way of a suction chamber and discharges the compressed gas to the external circuit by way of a discharge chamber. The cam plate is tiltable between a maximum inclined angle position and a minimum inclined angle position with respect to a plane perpendicular to an axis of the drive shaft according to a difference between the pressure in the crank chamber and the pressure in the cylinder bore. The piston moves by the stroke based on an inclination of the cam plate to control the displacement of the compressor. A valve is placed between the discharge chamber and the external circuit.

Abstract: A variable capacity piston-operated refrigerant compressor having a cylinder block provided with cylinder bores in which single-headed pistons are reciprocated to compress a refrigerant gas, and a housing assembly arranged on opposite ends of the cylinder block to define a crank chamber for receiving a cam plate mounted around a rotatably supported drive shaft to cause the reciprocating motion of the pistons in response to the rotation thereof together with the drive shaft, the cam plate further controlling the stroke of the reciprocation of the pistons by the use of a differential pressure between a suction pressure acting on working ends of the respective pistons via a suction chamber and a pressure in the crank chamber communicating with a discharge chamber via a gas supply passage for supplying the discharge pressure refrigerant gas containing therein a lubricating oil which is separated from the refrigerant gas by the oil separating means arranged in the gas supply passage immediately before the refriger

Abstract: A drive plate or lug plate is supported on a drive shaft for integral rotation therewith. A cam plate is coupled to the lug plate by a hinge mechanism to integrally rotate with the drive shaft and tilt with respect to the axis of the drive shaft. The cam plate is coupled to a piston to convert the rotation of the drive shaft into linear reciprocating movement of the piston in a cylinder to compress gas supplied from an external circuit and to discharge the compressed gas outward from the cylinder. The hinge mechanism has a first guide pin projecting to the lug plate from the cam plate, a second guide pin projecting to the lug plate from the cam plate in a position following the first guide pin which is the leading pin with respect to the direction of rotation of the drive shalt, a first guide hole formed in a support arm projecting from the lug plate to receive the first guide pin and a second guide hole formed in a second support arm projecting from the drive plate to receive the second guide pin.

Abstract: A housing of a compressor has a shutter chamber for accommodating a shutter. The shutter moves between a closed position, where the shutter stops flow of gas from an external circuit into a suction chamber, and an open position, where the shutter permits the gas flow in response to the tilting motion of a swash plate. A coil spring, which has a conical shape, is located in the shutter chamber to bias the shutter in a direction toward the open position from the closed position. The spring is arranged to prevent the spring from sliding against the inner wall of the shutter chamber when the spring is expanded or contracted by movement of the shutter member.