摘要:
A control valve controls the displacement of a variable displacement type compressor. The compressor has a crank chamber, a bleed passage, and a supply passage. An outlet valve portion located on the bleed passage to control the opening of the bleed passage. An inlet valve portion is located on the supply passage to control the opening of the supply passage. A transmission rod extends between the outlet valve portion and the inlet valve portion to connect the outlet valve portion to the inlet valve portion. The transmission rod moves axially. A through hole is located in the inlet valve portion to receive a part of the transmission rod. The through hole constitutes a part of the supply passage. A clearance is formed between the transmission rod and the through hole to constantly connect the discharge pressure zone to the crank chamber.
摘要:
A control valve controls the displacement of a variable displacement type compressor. The compressor includes a crank chamber, suction chamber, a bleed passage, and a supply passage. The control valve has a supply side valve, a transmission rod, and a relief side valve. The transmission rod connects the relief side valve with the supply side valve. The relief side valve includes a passage chamber constituting part of the bleed passage. The passage chamber is separated into a first area, which is connected to the crank chamber, and a lower area, which is connected to the suction chamber. A pressure sensing member moves the relief side valve body in accordance with the pressure in the upper area. The effective pressure receiving area of the sensing member is substantially equal to the cross sectional area of the passage chamber that is sealed by the relief side valve body.
摘要:
A variable displacement compressor is operated efficiently by avoiding inefficient conditions. The compressor varies its displacement using a control valve for which an external duty control procedure is performed. A target value for controlling the displacement is determined in accordance with the duty ratio Dt of a drive signal sent to the control valve. If the duty ratio Dt is equal to or greater than a predetermined reference value DJ, the displacement is permitted to be varied corresponding to the duty ratio Dt. If the duty ratio Dt is smaller than the reference value DJ, the variable displacement control through the duty control procedure is suspended. In this case, the compressor is operated with a nullified duty ratio (Dt=0), or a minimum displacement.
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:
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:
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:
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.