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. 04, 1994
Filed:
Nov. 22, 1991
Tatsuya Uesugi, Higashi-Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
A valve operating system for an engine includes a cam shaft and first and second cams, mounted on the cam shaft, which are selectively utilized to provide different valve opening characteristics in accordance with a vehicle operating condition. A first rocker arm follows the first cam and engages a valve stem of a valve to operate the valve, and a second rocker arm follows the second cam at a position not interfering with the valve stem. A connecting device connects the first and second rocker arms so that they move together, and a control device controls the connecting means to connect the first and second rockers in accordance with the vehicle operating condition so that the valve opening characteristic is defined by a cam profile of the second cam which is larger than that of the first cam. When the first and second rocker arms are engaged with each other, the valve opening period is increased to reduce pumping loss in the engine under relatively low engine load.