Patent ID: 6386834
Filing Date: 2002-05-14
Classification: F04B

Abstract:
A control valve for a cooling apparatus having a compressor, which includes a displacement control mechanism, and an external refrigerant circuit, which is connected to the compressor to form, together with the compressor, a cooling circuit, wherein the control valve changes the discharge displacement of the compressor by controlling a control pressure that acts on the displacement control mechanism, the valve comprising:a housing; an internal passage provided in the housing, the internal passage including a valve chamber; a movable valve body provided in the valve chamber for controlling the opening degree of the internal passage; a first pressure sensing structure, which senses the difference between two pressure monitoring points located in the cooling circuit, wherein the difference is a primary pressure, wherein the first pressure sensing structure transmits a force corresponding to the primary pressure to the valve body; and a second pressure sensing structure, which senses a secondary pressure that is different from the primary pressure and applies a force corresponding to the secondary pressure to the valve body, wherein the valve body is positioned in the valve chamber by a combination of forces corresponding to the primary pressure and the secondary pressure to control the opening degree of the internal passage.