摘要:
A control valve controls the pressure in a crank chamber of a compressor to change the displacement of the compressor. The compressor includes a discharge chamber, a suction chamber and a supply passage, which connects the discharge chamber to the crank chamber. The control valve regulates the supply passage. The control valve includes a valve body, a spool and a solenoid. The valve body adjusts the size of an opening in the supply passage. The spool moves the valve body in accordance with the difference between the pressure in the discharge chamber and the pressure in the suction chamber. The solenoid urges the valve body by a force, the magnitude of which corresponds to a supply of electricity. The urging force of the solenoid represents a target value of the pressure difference. The spool moves the valve body such that the pressure difference seeks the target value. The control valve, which is located in the compressor, permits the compressor displacement to be accurately controlled regardless of a thermal load on an evaporator.
摘要:
An engine control apparatus of a vehicle having an air conditioner that has a variable displacement compressor is disclosed. The pressure difference between two points in a refrigeration circuit is monitored. The pressure difference represents the compressor displacement. The compressor is controlled by a control valve. The control valve operates based on the pressure difference. A controller compares the temperature of the passenger compartment with a temperature setting. If they differ, the controller determines a target pressure difference for the control valve. The controller computes the compressor torque based on the target pressure difference signal. The controller determines a target engine torque based on the compressor torque and controls the engine based on the target engine torque.
摘要:
Compressor has a driving unit. The driving unit is provided within a crank chamber and decreases the discharge capacity when a control valve opens a control passage to increase the pressure within the crank chamber. The throttle passage delivers oil with the compressed refrigerant to the crank chamber regardless of whether the control valve has opened or closed the control passage. Because the throttle passage may continuously deliver the oil to the crank chamber even when the control valve closes the control passage, the mechanical elements within the crank chamber can be reliably and sufficiently lubricated and the crank chamber is prevented from being in an insufficiently lubricated state.
摘要:
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.
摘要:
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. This moves the valve body and increases the size of the pressurizing passage.
摘要:
A lug plate 11 is secured to a drive shaft 7 which is rotatably supported in a housing so as to rotate together with the drive shaft, and a swash plate 12 is operatively connected to the lug plate through a hinge mechanism so as to rotate together with the lug plate and so as to vary an angle with respect to the drive shaft 7. Pistons 17 which are received in cylinder bores la so as to reciprocally move are operatively connected to the swash plate 12, so that not only can a refrigerant be introduced and discharged in accordance with the rotation of the drive shaft 7, but also the stroke of the pistons 17 can be varied by varying the angle of the swash plate 12. A front radial bearing 9B is provided on the outer periphery of a boss portion 11A of the lug plate 11 and a coil spring 16 to bias the swash plate 12 is received in a spring receiving portion 11C formed in the lug plate 11 on the rear side thereof.
摘要:
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.
摘要:
An air conditioner having a refrigerant circuit that maintains a high cooling efficiency and a sufficient amount of oil returned to a compressor even if the flow rate of refrigerant is decreased due to a low cooling load is provided. The refrigerant circuit includes a condenser, an expansion valve, an evaporator and a variable displacement compressor. The expansion valve is normal-charge type. A control valve adjusts the pressure in a crank chamber based on the value of a current from a controller and on a pressure difference between two pressure monitoring points, which are located in the refrigerant circuit. Accordingly, the compressor displacement and the flow rate of refrigerant in the circuit are controlled.
摘要:
A control valve has a valve housing. A valve chamber and a pressure sensing chamber are defined in the valve housing, respectively. A pressure sensing member is located in the pressure sensing chamber. A pressure sensing rod is slidably supported by the valve housing. A valve body is accommodated in the valve chamber. An end of the pressure sensing rod is connected to the pressure sensing member and the other end of the pressure sensing rod contacts the valve body. A solenoid chamber is defined in the valve housing. A stationary iron core is located between the valve chamber and the solenoid chamber. A solenoid rod extends through and is slidably supported by the stationary iron core. An urging force applied to the pressure sensing member by an actuator through the solenoid rod corresponds to a target value of the pressure difference. The pressure sensing member moves the valve body such that the pressure difference seeks the target value.
摘要:
Valve and separator unit is mounted to a housing of a compressor. The unit includes a check valve for preventing the reverse flow of refrigerant, and an oil separator for separating a mist of lubricating oil contained in the refrigerant from the refrigerant. Separated lubricating oil is introduced into a crank chamber via an oil passage, and the separated refrigerant is directed to the check valve, which prevents of the reverse flow of the refrigerant from the external refrigerant circuit to the discharge chamber.