The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 02, 1980
Filed:
Oct. 04, 1979
Richard E Widdowson, Dayton, OH (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A pressure operated control valve operative to regulate the flow of fluid to a hydraulic modulating cylinder having a fixed hydraulic bleed which cylinder operates a mechanism for varying the displacement of a compressor of an automotive air conditioning system to maintain a predetermined control or system pressure. The system pressure continually surrounds a sealed bellows seated in the closed end of a tubular bellows cover. High pressure fluid is continually supplied to the control valve which has a ball and seat to totally restrict fluid flow to the modulating cylinder when the system pressure exceeds the setting pressure of the valve. When the system pressure drops below the setting pressure, the bellows extends against an axial pin which forces the ball from its seat, thus allowing high pressure fluid to flow to the compressor modulating cylinder operating the compressor mechanism and reducing the stroke of the compressor pistons. When the system pressure returns to the setting pressure, the bellows retracts moving the ball toward its seat thereby reducing hydraulic fluid flow to the modulating cylinder.