US 6,457,319 B1Granted

Air conditioner and control valve in variable displacement compressor

AssigneeKabushiki Kaisha Toyoda Jidoshokki Seisakusho

InventorsMasaki Ota, Ken Suitou, Ryo Matsubara, Hirotaka Kurakake

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Abstract

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.

Claims14

Dependent claims

An air conditioner including a refrigerant circuit, the refrigerant circuit having a condenser, a decompression device, an evaporator and a variable displacement compressor, wherein the compressor has a discharge pressure zone, the pressure of which is a discharge pressure, and a suction pressure zone, the pressure of which is a suction pressure, wherein the refrigerant circuit further has a high pressure passage extending from the discharge pressure zone to the condenser and a low pressure passage extending from the evaporator to the suction pressure zone, the air conditioner comprising:

a displacement control mechanism, which controls the displacement of the compressor based on the pressure difference between the pressure at a first pressure monitoring point located in the refrigerant circuit and the pressure at a second pressure monitoring point located in the refrigerant circuit, wherein the first pressure monitoring point is located in a section of the refrigerant circuit that includes the discharge pressure zone, the condenser and the high pressure passage, and wherein the second pressure monitoring point is located in a section of the refrigerant circuit that includes the evaporator, the suction pressure zone and the low pressure passage;
detectors for detecting external information used for controlling the compressor displacement other than the pressure difference;
and
a controller, which determines a target value of the pressure difference based on the detected external information, wherein the controller commands the target value to the displacement control mechanism, and wherein the displacement control mechanism controls the compressor displacement such that the actual pressure difference seeks the target value.

1 more element

A control valve for controlling the pressure in a crank chamber of a compressor to change the displacement of the compressor, wherein the compressor has a discharge pressure zone, the pressure of which is a discharge pressure, a suction pressure zone, the pressure of which is a suction pressure, and an internal gas passage that includes the discharge pressure zone, the crank chamber and the suction pressure zone, the control valve comprising:

a valve housing;
a valve body located in the valve housing, wherein the valve body adjusts the size of an opening in the internal gas passage;
a pressure receiver, wherein the pressure receiver actuates the valve body in accordance with the pressure difference between the discharge pressure and the suction pressure thereby causing the pressure difference to seek a predetermined target value;
and
an actuator for urging the valve body by a force, the magnitude of which corresponds to an external command, wherein the urging force of the actuator represents the target value of the pressure difference.

2 more elements

Dependencies are inferred from the claim text.