CONTROL VALVE FOR VARIABLE DISPLACEMENT COMPRESSOR

• US 20090035156A1
• Filed: 01/31/2007
• Published: 02/05/2009
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: Eagle Industry Company Limited
• Original Assignee: Eagle Industry Company Limited
• Inventors: Higashidozono, Hideki, Fukudome, Kohei, Uemura, Norio
• Granted Patent: US 8,449,266 B2
• Time in Patent Office: Days
• US Class Current: 417/270
• CPC Class Codes: F04B 2027/1827 between crankcase and discharge chamber
• CPC Class Codes: F04B 2027/185 Discharge pressure
• CPC Class Codes: F04B 2027/1854 External parameters
• CPC Class Codes: F04B 2027/1859 Suction pressure
• CPC Class Codes: F04B 27/1804 Controlled by crankcase pressure

Abstract

[Problems] A control valve for a variable displacement compressor, where sliding resistance by movement of a valve is reduced as much as possible to stably and accurately regulate the rate of air flow, enabling a suction pressure corresponding to solenoid thrust to be maintained.

[Means for Solving Problems] The discharge pressure Pd of the compressor introduced into a pressure sensing section (40) applies urging force to a movement member (50), and a solenoid section (36) applies, in cooperation with the urging force, urging force to the movement member (50) depending on an input signal. The degree of opening of a valve body (56) provided at the movement member (50) is set according to the position of the movement member (50) to regulate the rate of air flow in a communication path for interconnecting a discharge pressure region of the compressor and a compressor inner chamber. The suction pressure Ps of the compressor is introduced into a control valve to apply urging force to the movement member (50), and communication between fluid having the discharge pressure Pd introduced into the pressure sensing section (40) and fluid having the suction pressure Ps introduced into the control valve is shut off.

Claims

1. A control valve for a variable displacement compressor comprising a pressure sensing section, a solenoid section, and a valve section composed of a valve element that is provided to a movement member, wherein an internal pressure of the compressor is adjusted by a degree of opening of the valve element, and a discharge displacement is varied;

said control valve for a variable displacement compressor characterized in that

a discharge pressure of the compressor introduced to said pressure sensing section applies an urging force to said movement member;

said solenoid section applies, in cooperation with the urging force, an urging force to the movement member in accordance with an input signal;

a degree of opening of said valve element is set in accordance with a position of said movement member;

a rate of air flow of a communicating channel for communicating a compressor inner chamber with a discharge pressure region of the compressor is adjusted;

a suction pressure of said compressor is introduced to the control valve to apply an urging force to the movement member; and

communication between a fluid having said discharge pressure introduced to said pressure sensing section, and a fluid having the suction pressure introduced to said control valve, is blocked by contact of said movement member and an expanding and contracting member constituting the pressure sensing section.

2. The control valve for a variable displacement compressor according to claim 1, characterized in that a sealed chamber acted on by the suction pressure of said compressor is formed in a portion of contact between said expanding and contracting member and the movement member.