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:
Jan. 31, 1989
Filed:
Dec. 24, 1987
Kazuo Yoshida, Tokyo, JP;
Koichi Fukuo, Saitam, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A hydraulic circuit for a valve operating mechanism for an internal combustion engine which has a plurality of intake or exhaust valves normally urged in a valve closing direction, a plurality of adjacent rocker arms associated respectively with the intake or exhaust valves and pivotably supported on a rocker shaft. The rocker arms are pivotable by cams rotatable in synchronism with a crankshaft. A coupling mechanism is provided in the rocker arm selectively interconnecting and disconnecting adjacent rocker arms in response to oil pressure. A hydraulic circuit supplies oil pressure to the coupling means and an oil feed passage lubricates the cams. The hydraulic circuit and oil feed passage are connected in series to each other through a flow restriction and the hydraulic circuit includes a directional control valve for changing the direction of flow of lubricating oil supplied from an oil pump to cause the lubricating oil to flow from the oil feed passage to the hydraulic circuit during low-speed operation of the engine and to cause the lubricating oil to flow from the hydraulic circuit to the oil feed passage during high-speed operation of said engine to always provide the proper oil pressure levels in the oil feed passage and the hydraulic circuit.