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:
Oct. 18, 1977
Filed:
Mar. 31, 1976
Ronald J Herrin, Clawson, MI (US);
Donald J Pozniak, Sterling Heights, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
Variable overlap of the intake and exhaust valve opening periods for an internal combustion engine is obtained by providing a speed responsive yieldable link in the valve actuating mechanism that varies the effective valve lift with engine speed. The variation is accomplished by flow responsive valves, preferably incorporated in hydraulic tappets for actuating the valves and arranged to begin valve lift only when a predetermined lift rate of the valve actuating cam is reached. Since this rate is reached earlier as the engine speed increases, a greater portion of the cam lift curve is utilized with increased speed, thus increasing the valve lift and extending the valve opening period relative to crankshaft rotation. In this way, angular overlap of the intake and exhaust valve opening periods is varied as a function of engine speed.