Abstract: A valve housing has a communication passage communicating a suction port of the compressor with a crank chamber of the compressor. A valve element opens and closes the communication passage, and a spring member resiliently biases the valve element toward the closed position. A pressure actuated unit moves the valve element toward the open position by a suction pressure of the compressor. The spring member includes a spring made of a temperature responsive material. The spring decreases in its resilient force in an opening direction of the valve element with increase of an outer-air temperature. The spring member has a primary spring made of an ordinary resilient material for resiliently biasing the valve element toward the closed position and a correction spring made of a material having a temperature positive characteristic. The correction spring provides a correction spring force smaller than a primary force of the primary spring in the opposite direction to the primary force.

Abstract: A control valve is located in a variable displacement compressor incorporated in a refrigerant circuit. The control valve controls the displacement of the compressor in accordance with a pressure difference between a first pressure monitoring point and a second pressure monitoring point, which are located in the refrigerant circuit, such that the pressure difference seeks a predetermined target value. An adjusting valve, which is a variable throttle valve, is located in a section of the refrigerant circuit between the first and second pressure monitoring points. The adjusting valve adjusts the restriction amount of the refrigerant in relation to the refrigerant flow in the refrigerant circuit. The compressor displacement is thus optimally controlled.

Abstract: A swash plate type compressor of variable capacity type including a rotary drive shaft, a swash plate carried by the drive shaft such that its inclination angle is variable, and such that the swash plate is rotated with the drive shaft, pistons slidably fitted in cylinder bores and engaging a radially outer portion of the swash plate, each piston being reciprocated between compression and suction stroke ends by rotation of the swash plate, the radially outer portion including a compression-end circumferential part engaging each piston located at the compression stroke end, a swash plate angle adjusting device for adjusting the inclination angle between a minimum and a maximum angle, and wherein the_swash plate has a first center point at the maximum inclination angle and a second center point at the minimum inclination angle, each of the center points being an intersection between an intermediate plane of the swash plate which is intermediate in the thickness direction and a centerline of the swash plate, the

Abstract: An improved control apparatus for a vehicle air conditioning system controls a variable displacement compressor. The discharge capacity of the compressor is changed by changing the difference between the pressure in the crank chamber and the suction pressure. The difference between the pressure in the crank chamber and the pressure of the suction chamber is maintained at a set value. A target value is determined based on the temperature of the passenger compartment. The target value is corrected based on the rotational speed of the engine driving the compressor, which is detected. The set value is determined by the corrected target value.

Abstract: A control valve includes a valve chamber. A valve body is located in the valve chamber. A first regulator regulates the movement of the valve body. A first spring urges the valve body towards the first regulator. A sensing member divides a sensing chamber into a first pressure chamber and a second pressure chamber. The sensing member moves in accordance with the pressure difference. A regulator surface regulates the movement of the sensing member. A temporary chamber is formed between the sensing member and the valve body when the valve body is disconnected from the sensing member. The temporary chamber is connected to the second pressure chamber. A second spring urges the sensing member toward the regulator surface. An actuator applies a force to the valve body that is opposite to the force of the first spring and that of the second spring in accordance with commands from an external controller.

Abstract: A wear-resistant piece 29 is attached to a swash place 20 supported for inclination according to the present invention. The maximum inclination angle of the swash plate 20 is defined by the contact of rotary support 19 rotatable together with a rotary shaft 18. The rotary shaft 18 rotates in the arrowed direction Q, and the position at which the wear-resistant piece 29 is attached is contained in a discharge stroke region De on the swash plate 20 wherein a piston 26 carries out the discharge operation.

Abstract: A controller controls a displacement of a compressor which is installed in a refrigerant circuit of an air-conditioning system. The controller has a pressure difference detector. An air conditioning switch turns the air conditioning system on. A temperature detector detects the temperature in a compartment. A control valve controls the displacement of the compressor such that the pressure difference detected by the pressure difference detector approaches a target value. A computer determines the target value. The computer changes the target value, depending on the detected temperature. The computer limits the target value to a target value limit. After a predetermined time expires from when the air conditioning switch is turned on, the computer changes the limit. This permits the displacement of the compressor to be promptly and reliably changed.

Abstract: An improved control apparatus for controlling the displacement of a variable displacement compressor. A control valve includes an operating rod, which is urged by a force based on a differential pressure between two pressure monitoring points, which are located in a refrigeration circuit. The control valve causes the compressor to seek a target displacement. A computer limits the target displacement when the demand for cooling is decreasing to improve fuel economy and to extend the life of the compressor.

Abstract: A variable displacement compressor 10 comprises a wall 1a that seals a cylinder bore 14, and is integrally formed with a cylinder block 1. A rear plate 5 having a plate-like shape is fastened via a gasket 6 to a location that extends to the inner rear side of a wall 1a. Suction valves 40 and discharge valves 44 are disposed within the wall 1a.

Abstract: A torque limiting mechanism for transmitting power from an external drive source to the drive shat of a compressor. A pulley, which is coupled to the external drive source, has elastic members. A hub, which is attached to the drive shaft, has engaging portions. A coupler member is located between the pulley and the hub. The coupler member is engaged with the elastic members and with the engaging portions such that power is transmitted from the pulley to the hub. The urging members urge the coupler member such that the coupler member is disengaged from the engaging portions. When power is transmitted from the pulley to the hub, the elastic members maintain the coupler engaged with the elastic members and the engaging portions. When load generated due to power transmission exceeds a predetermined level, the elastic members are deformed such that the coupler member is disengaged from the elastic members. When disengaged from the elastic members, the coupler member is disengaged from the engaging portions.

Abstract: A torque limiting mechanism includes a pulley and a hub. The pulley has a transmission spring. The hub has a groove. A transmission ring is engaged with the transmission spring such that power can be transmitted between the pulley and the hub. The transmission ring includes a coupler block and a coupler. The coupler block is engaged with the transmission spring and the groove. The coupler is connected to the coupler block. The coupler urges the coupler block in a direction disengaging the coupler block from one of the transmission spring and the groove. When the load between the pulley and the hub exceeds a predetermined level, the coupler block is disengaged from the pulley and the hub. Thereafter the coupler keeps the coupler block disengaged from the pulley and the hub. This positively discontinues power transmission according to an applied load and maintains the discontinuation.

Abstract: A variable displacement compressor has a housing, which defines a crank chamber, a suction chamber, and a discharge chamber. A bleed passage connects the crank chamber to the suction chamber, which allows gas to flow from the crank chamber to the suction chamber. A release valve, which is a reed valve, is located in the bleed passage. The release valve varies the opening of the bleed passage in accordance with the difference between the pressure in the crank chamber and the pressure in the suction chamber. This can prevent the pressure in the crank chamber from excessively increasing.

Abstract: A control valve is located in a variable displacement compressor used in a refrigerant circuit. The control valve operates such that the pressure difference between two pressure monitoring points in the refrigerant circuit seeks a predetermined target value. A controller determines the target value of the pressure difference in accordance with external information that represents the required cooling performance. The target value of the pressure difference is represented by a duty ratio applied to the control valve. When the acceleration pedal is pressed beyond a predetermined level, the controller limits the duty ratio. Therefore, the compressor torque does not hinder quick vehicle acceleration. Also, the cooling performance is not lowered unless it is necessary.

Abstract: A displacement control valve for a compressor is provided. When current to a coil is stopped due to, for example, a broken wire, the control valve prevents the load acting on a variable displacement compressor from becoming excessive. A suction chamber is connected to a crank chamber by a control passage. A bellows actuates a valve body in accordance with the pressure in a suction chamber thereby regulating the opening size of the control passage. The compressor displacement is varied accordingly. A solenoid varies the attraction between a plunger and a fixed core in accordance with the level of current supplied to a coil thereby changing a target pressure. The bellows is actuated based on the target pressure. The solenoid increases the target pressure as the current to the coil is decreased. When the current to the coil is stopped, the solenoid maximizes the target pressure.

Abstract: A variable displacement compressor the displacement of which is externally controlled is provided. The compressor has basically the same structure as prior art compressors except for simple differences. A pressure sensing chamber of a displacement control valve is connected to a suction chamber by an outlet passage. A bellows is located in the pressure sensing chamber. The bellows expands and contracts in accordance with the pressure in the sensing chamber. A valve chamber forms part of a displacement control passage, which is used to control the pressure of a crank chamber. A valve body is located in the valve chamber. The valve body is moved by the bellows to open and close the displacement control passage. Highly pressurized gas from the discharge chamber is supplied to the pressure sensing chamber through an inlet passage. The gas in the pressure sensing chamber is released to the suction chamber through the outlet passage.

Abstract: A single headed piston type refrigerant compressor having a cylinder block forming therein a plurality of cylinder bores receiving a plurality of single-headed pistons for reciprocation therein, and a front housing joined to the cylinder block to define a crank chamber for receiving therein a cam plate. An extended bore-forming portion of the cylinder block having partial cylindrical guide surfaces each being continuous with the corresponding cylinder bore and capable of being in slide contact with the piston head portion of the single-headed piston and the outer circumference of a shoe-holding portion of the single-headed piston is formed by extending a peripheral portion of a front end of the cylinder block into the crank chamber. A projecting portion formed on each single head piston protrudes from a side end surface of the shoe-holding portion extending behind the piston head portion into the crank chamber.

Abstract: A control valve varies the displacement of a variable displacement compressor. A pressure chamber is connected to a suction chamber through a fixed throttle and to a discharge chamber through an intake passage. The intake passage includes a fixed throttle and an electromagnetic valve. A controller controls the electromagnetic valve in accordance with data related to the running conditions of the vehicle. The control valve has a threshold value that changes in accordance with the opening and closing of the electromagnetic valve.

Abstract: A variable displacement type refrigerant compressor including a compressor housing having internally a compressing mechanism for compressing a refrigerant, a displacement varying mechanism for adjustably varying an amount of the refrigerant compressed and discharged by the compressing mechanism, and a displacement control valve unit controlling the operation of the displacement varying mechanism, which is an assembly of a pressure sensing mechanism formed by a flanged bellows element, a valve element, a valve seat having a port cooperating with the valve element, and a valve rod engaging the pressure sensing mechanism with the valve element, and are assembled by using a fixing screw member and a jig tool in position in a pressure sensing chamber, a valve chamber, and a valve rod bore coaxially formed in the compressor housing by drilling or boring from two sides of the compressor housing.

Abstract: A variable displacement compressor has a housing, which defines a crank chamber, a suction chamber, and a discharge chamber. A release passage connects the crank chamber to the suction chamber, which allows gas to flow from the crank chamber to the suction chamber. A release valve is located in the release passage. The release valve regulates gas flow in the release passage. A controller controls the release valve to limit the pressure in the crank chamber to prevent the pressure in the crank chamber from becoming undesirably high. This can prevent the pressure in the crank chamber from excessively increasing.

Abstract: A variable displacement compressor that decreases displacement to reduce compression load without imbalancing the rotation of the drive shaft when the rotating speed of the compressor's drive shaft exceeds a predetermined limit value. The compressor includes a pressurizing passage connecting a crank chamber to a discharge chamber. A rotated guide rotates integrally with the drive shaft. The pressurizing passage is opened and closed by a valve body. Orbiting balls, which contact the valve body, are arranged about the axis of the drive shaft and the rotated guide. The balls follow the rotation of the rotated guide and orbit about the axis. The orbiting radius of the balls varies. A spring urges the balls in a direction decreasing the orbiting radius of the balls. When the rotating speed of the drive shaft exceeds the limit value, centrifugal force moves the balls against the force of the spring and increases the orbiting diameter of the balls.