摘要:
A control valve used for a variable displacement type compressor. The compressor has a crank chamber, a discharge pressure zone, and a supply passage. The supply passage connects the crank chamber to the discharge pressure zone. The control valve is located in the supply passage. The control valve has a valve body. The valve body adjusts the size of the opening of the supply passage in accordance with the discharge pressure. The valve body is exposed to the pressure of the supply passage. The valve body moves in accordance with the discharge pressure such that the displacement is varied to counter changes of the discharge pressure. The direction in which the valve body moves in response to an increase of the discharge is the same as the direction in which the valve body moves when the pressure of the supply passage increases.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A control valve is located in a variable displacement compressor that is installed in a refrigerant circuit. The control valve operates such that the pressure difference between first and second pressure monitoring points in the refrigerant circuit seeks a predetermined target value. The first pressure monitoring point is located in a discharge chamber of the compressor. The second pressure monitoring point is located in a flow pipe that extends from the discharge chamber. The static pressure of refrigerant in the discharge chamber is introduced into a control valve from the first pressure monitoring point. A pressure that includes the static pressure and the dynamic pressure of refrigerant in the flow pipe is introduced into the control valve from the second pressure monitoring point. As a result, the displacement of the compressor is reliably controlled without being affected by the thermal load of an evaporator.
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 valve body adjusts opening of a supply passage in response to the position in a valve chamber. A pressure-sensitive member is moved in accordance with the pressure difference between two pressure monitoring points, which are located in an external refrigerant circuit. The movement of the pressure-sensitive member affects the position of the valve body such that the compressor displacement is changed to reduce fluctuations in the pressure difference. A solenoid changes force applied to the valve body so that a set pressure difference, which is a reference value for changing the position of the valve body by the pressure-sensitive member, is changed.
摘要:
An air-conditioning system has a refrigerant circuit. The circuit includes a condenser, a expansion valve, an evaporator and a variable displacement compressor. The system has a pressure difference detector. The pressure difference detector detects the pressure difference between two pressure monitoring points located on the refrigerant circuit. A control valve and a controller control the displacement of the compressor in accordance with the pressure difference detected by the pressure difference detector. This permits the displacement of the compressor to be quickly changed.
摘要:
A control valve used for a variable displacement compressor comprises a valve housing, a valve chamber defined in the valve housing, a valve body. The valve body is located in the valve chamber. A pressure sensing chamber is defined in the valve housing. A movable wall is located in the sensing chamber to divide a first pressure chamber and a second pressure chamber. The movable wall moves in accordance with the pressure difference between the first pressure chamber and the second pressure chamber. A rod transmits the movement of the movable wall to the valve body. The pressure directed in the vicinity of the end portion of the rod is the same type pressure directed in the first pressure chamber or in the second pressure chamber. An actuator determines the target pressure difference between the two pressure chambers. This permits the displacement of the compressor to be quickly changed.
摘要:
An air-conditioning system for a vehicle, including a refrigerant circuit and an engine, has a battery, a compressor, an electric motor and a load torque control mechanism. The battery supplies electric power. The compressor is operative to compress refrigerant gas for the air-conditioning system. The electric motor is electrically connected to the battery. The motor is driven due to the electric power, and is operatively coupled to drive the compressor when the motor is energized. The load torque control mechanism responsive to the operating condition of the engine to control the load torque of the compressor below a predetermined value during times when the motor is driving the compressor.