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:
May. 13, 1986
Filed:
Dec. 24, 1984
Robert C Hikade, Sussex, WI (US);
Vilter Manufacturing Corporation, Milwaukee, WI (US);
Abstract
A gas compressor has cylinders in which gas is compressed by pistons. Each cylinder has a suction valve and an exhaust valve to admit uncompressed gas and expel compressed gas. The suction valve includes a suction valve plate which repeatedly moves toward and away from the top end of the cylinder between closed and open positions, respectively. Apparatus to control compressor capacity includes an unloader mechanism to selectively prevent the suction valve plate moving to fully closed position to thereby unload the cylinder and reduce compressor capacity. The unloader mechanism comprises an unloader piston movable in an unloader cylinder in response to system conditions to move a linkage which determines the closure position of the suction valve plate. The linkage includes a pivotable lift arm biased toward a position which allows full closure of the suction valve plate and is movable by the unloader piston to another position which prevents full closure of the suction valve plate. The unloader piston, which merely rests on the lift arm and is relatively massive so as to reduce chatter caused by reciprocation of the suction valve plate, is accessible for removal and service of a piston ring thereon merely by removal of the cylinder cover.