Abstract: A seal is provided between the housing assembly of a variable displacement compressor and a rotary shaft to seal inside the housing assembly. The seal is retained in a retaining chamber, which is separated from a suction chamber and a control pressure chamber. A refrigerant passage is connected to the retaining chamber to feed a refrigerant to the retaining chamber to cause the refrigerant to contact the seal. The refrigerant passage includes a path extending from outside the housing assembly to the suction chamber through the retaining chamber. A restriction ring having a restriction function guides the refrigerant from the control pressure chamber to the retaining chamber and releases an internal pressure of the control pressure chamber.

Abstract: A variable displacement compressor includes a housing assembly having a control pressure chamber. A drive shaft is rotatably supported by the housing assembly. Cylinder bores, each accommodating a piston, are formed about the drive shaft. Each piston defines a compression chamber inside the corresponding cylinder bore. Each piston compresses refrigerant drawn into the corresponding compression chamber from a suction pressure zone and discharges the refrigerant to a discharge pressure zone. The inclination of a swash plate changes in accordance with the pressure in the control pressure chamber. A supply passage connects the control pressure chamber to the discharge pressure zone. A pressure release passage connects the control pressure chamber to the suction pressure zone. A shutter, which is made of synthetic resin or rubber and includes a restricting passage, closes one of the supply passage and the pressure release passage.

Abstract: A piston type variable displacement fluid machine includes a drive shaft and a cylinder bore. A piston reciprocates along a line of movement in the cylinder bore in accordance with the rotation of the drive shaft. The stroke of the piston is varied between the maximum stroke and the minimum stroke, which is greater than zero. The displacement of the fluid machine is changed in accordance with the stroke of the piston. A ring groove is formed on the outer circumferential surface of the piston. A piston ring is fitted in the ring groove and moves with respect to the piston in the line of movement of the piston. An allowable movement amount of the piston ring with respect to the piston is greater than or equal to the minimum stroke of the piston.

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 compressor has a housing and a cylinder block. The housing includes suction and discharge chambers. The cylinder block is fixed to the housing via a valve plate assembly. The valve plate assembly forms suction and discharge ports and suction and discharge valves. A partition wall is formed with the housing, and separates the suction chamber and the discharge chamber. The housing includes a first surface, and the cylinder block includes a second surface. At least one of the first and second surfaces is concave in shape. The cylinder block is screwed to the housing at the partition wall or a position closer to the central axis of the housing than the partition wall by a bolt so that the first surface faces the second surface.

Abstract: A control device includes a first passage, a second passage, a third passage, a displacement control valve and an auxiliary valve. The displacement control valve is placed in the first passage. The auxiliary valve includes a valve chamber, a spool valve and an urging means. The spool valve is slidably accommodated in the valve chamber. The spool valve divides the valve chamber into a first pressure chamber and a second pressure chamber, to communicate the first pressure chamber with the first passage and to communicate the second pressure chamber with the second passage. The urging means is placed in the valve chamber for urging the spool valve toward the first pressure chamber. The third passage communicates with the first pressure chamber and/or the second pressure chamber by the movement of the spool valve.

Abstract: A control valve is used for a variable displacement compressor installed in a refrigerant circuit of a vehicle air conditioner. The control valve has a valve housing. A valve chamber is defined in the valve housing. A valve body is accommodated in the valve chamber. A pressure sensing chamber is defined in the valve housing. A pressure sensing member separates the pressure sensing chamber into a first pressure chamber and a second pressure chamber. The pressure at a first location in the refrigerant circuit is applied to the first pressure chamber. The pressure at a second location in the refrigerant circuit, which is downstream of the first location, is applied to the second pressure chamber. The pressure sensing member moves the valve body in accordance with the pressure difference between the first pressure chamber and the second pressure chamber such that the displacement of the compressor is varied to counter changes of the pressure difference.

Abstract: The compressor has a cooling structure to effectively cool a shaft seal device interposed between a housing of the compressor and a rotary shaft. The front housing has a through-hole through which the rotary shaft extends, and the shaft seal device is arranged in the through-hole. A passage (suction passage portion) is connected to the thorough-hole. An inlet from a portion of the passage to the through-hole is arranged right above the rotary shaft, and an outlet from the through-hole to a portion of the passage is arranged right below the rotary shaft. The passage is connected to a suction pressure region outside the compressor and to the suction chamber via the through-hole.

Abstract: The deformation of cylinder bores in a cylinder block is prevented. The cylinder block 19 is inserted into a front housing 11. The cylinder block 19 is fixed to the front housing 11 by tightening plural screws 38 which penetrate through the cylinder block 19, from an end surface 191 side thereof, to be screwed into an end wall 32 of the front housing 11. Plural deformation absorbing grooves 39 are provided on the end surface 191. Each one of the deformation absorbing grooves 39 is provided in each intermediate space between the adjacent paired cylinder bores 41.

Abstract: A gasket 36 is interposed between an end face 341 of a front housing 11 and an end face 351 of a rear housing 12. A coned disc spring 37 is interposed between an end face 192 of a cylinder 19 and the end face 341 of the front housing 11. When the end faces 341, 351 are caused to approach each other so as to be joined together, the coned disc spring 37 is first held by the end face 341 of the front housing 11 and the end face 192 of the cylinder 19. When the end faces 341, 351 are caused to approach each other further so as to be joined together, the gasket 36 is held between the end faces 341, 351. Thus, it is ensured that the cylinder and the seal material interposed between the first housing and the second housing are held therebetween.

Abstract: A shaft sealing assembly is located in a suction chamber of a swash plate type compressor to seal the space between a drive shaft and a housing. A first end portion of the drive shaft is supported by a first radial bearing. A second end portion of the drive shaft is supported by a second radial bearing. The suction chamber is closer to the first end portion of the drive shaft than the first radial bearing is. An axial passage is formed in the drive shaft to connect the suction chamber to the crank chamber. An inlet of the axial passage is closer to the second end portion than the second radial bearing is. An outlet of the axial passage is closer to the second end portion than the first radial bearing is.

Abstract: A piston type variable displacement compressor has a housing, a drive shaft, a first thrust regulating mechanism including a first thrust bearing and a second thrust regulating mechanism including a second thrust bearing. The drive shaft has a first end and a second end. The first end projects from the housing. The first thrust regulating mechanism regulates a drive shaft to move in the direction from the first end to the second end. The first thrust regulating mechanism allows the drive shaft to rotate. The first thrust bearing has a first radius. The second thrust regulating mechanism regulates the drive shaft to move in a direction from the second end to the first end. The second thrust regulating mechanism allows the drive shaft to rotate. The second thrust bearing has a second radius. The second radius is smaller than the first radius.

Abstract: In a variable-capacity swash-plate type compressor, which can vary the outlet capacity by controlling an inclination angle of a swash plate, the swash plate is aligned by contacting a washer (19) with a tapered surface to the swash plate (18). Thus, in a case where a compression operation is not carried out or in a case where a compression operation is carried out at a small outlet capacity regarded as zero substantially, the noises, etc., which generate between the swash plate and a driving shaft (6), are inhibited.

Abstract: A variable displacement piston type compressor has a housing, a drive shaft, a cam plate and a piston. The drive shaft is rotatably supported by the housing. The drive shaft has a first end and a second end. The first end of the drive shaft extends through the housing. The cylinder block is placed between the first end and the second end. The suction chamber and the discharge chamber are defined near the first end relative to the cylinder block. The crank chamber is defined near the second end relative to the cylinder block. The refrigerant in the crank chamber is bled into the suction pressure region through a bleed passage. Thereby, the inclination angle of the cam plate is controlled. The crank chamber and the suction chamber are connected with each other through the bleed passage. The bleed passage is formed outside of the drive shaft.

Abstract: A piston type variable displacement fluid machine includes a drive shaft and a cylinder bore. A piston reciprocates along a line of movement in the cylinder bore in accordance with the rotation of the drive shaft. The stroke of the piston is varied between the maximum stroke and the minimum stroke, which is greater than zero. The displacement of the fluid machine is changed in accordance with the stroke of the piston. A ring groove is formed on the outer circumferential surface of the piston. A piston ring is fitted in the ring groove and moves with respect to the piston in the line of movement of the piston. An allowable movement amount of the piston ring with respect to the piston is greater than or equal to the minimum stroke of the piston.

Abstract: A seal is provided between the housing assembly of a variable displacement compressor and a rotary shaft to seal inside the housing assembly. The seal is retained in a retaining chamber, which is separated from a suction chamber and a control pressure chamber. A refrigerant passage is connected to the retaining chamber to feed a refrigerant to the retaining chamber to cause the refrigerant to contact the seal. The refrigerant passage includes a path extending from outside the housing assembly to the suction chamber through the retaining chamber. A restriction ring having a restriction function guides the refrigerant from the control pressure chamber to the retaining chamber and releases an internal pressure of the control pressure chamber.

Abstract: A torque limiter to be operatively coupled to an engine is secured to the outer periphery of a driving shaft through screwing-engagement. The driving shaft and the torque limiter are screw-engaged and fixed to each other so that the torque limiter is pushed or urged against a seating face formed at the outer periphery of the driving shaft. The seating face abuts against the torque limiter restricting the screwing-movement of the driving shaft. Rotation force is transmitted between the driving shaft and the torque limiter via the seating face. A cylindrical member is disposed between the torque limiter and the seating face of the driving shaft. The cylindrical member is press-fitted and fixed to the outer periphery of the driving shaft, so that the power transmission between the driving shaft and the torque limiter is also performed through the press-fit portion between the cylindrical member and the driving shaft.

Abstract: A variable displacement compressor includes a housing assembly having a control pressure chamber. A drive shaft is rotatably supported by the housing assembly. Cylinder bores, each accommodating a piston, are formed about the drive shaft. Each piston defines a compression chamber inside the corresponding cylinder bore. Each piston compresses refrigerant drawn into the corresponding compression chamber from a suction pressure zone and discharges the refrigerant to a discharge pressure zone. The inclination of a swash plate changes in accordance with the pressure in the control pressure chamber. A supply passage connects the control pressure chamber to the discharge pressure zone. A pressure release passage connects the control pressure chamber to the suction pressure zone. A shutter, which is made of synthetic resin or rubber and includes a restricting passage, closes one of the supply passage and the pressure release passage.

Abstract: An apparatus controls a variable displacement compressor used in a refrigerant circuit. The compressor includes a drive shaft, which is rotated by an engine. When the drive shaft rotates, the compressor compresses refrigerant sent from the external refrigerant circuit and discharges the compressed refrigerant to an external refrigerant circuit. When the displacement of the compressor is minimized, the circulation of refrigerant in the refrigerant circuit is stopped. The apparatus has a control mechanism for varying the pressure in the crank chamber. A detector detects a physical quantity that reflects the heating status of the compressor. When the compressor displacement is minimized and the quantity detected by the detector indicates that the heating status of the compressor is deteriorating, a controller commands the control mechanism such that the displacement of the compressor is greater than the minimum displacement.

Abstract: A compressor includes a housing having a hollow projection portion, a rotary shaft provided rotatably within the housing, a piston reciprocating in accordance with rotation of the rotary shaft for sucking and discharging refrigerant, a bearing disposed within the projection portion of the housing for rotatably supporting one end of the rotary shaft and an attaching leg portion formed on an outer surface of the projection portion of the housing. The attaching leg portion is fastened to an engine block, a bracket or the like by using a bolt or the like.