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:
Mar. 20, 2001
Filed:
Feb. 04, 2000
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A valve operating control system for an internal combustion engine is provided which includes a cam switching type first valve operating characteristic changing mechanism, and a cam-phase changing type second valve operating characteristic changing mechanism, wherein the responsiveness and the reliability of the valve operating characteristic changing control can be guaranteed, while suppressing the capacity of an oil pump used commonly for both of the valve operating characteristic changing mechanisms. If the cam phase of the cam-phase changing type second valve operating characteristic changing mechanism is set in a most-retarded state by a second hydraulic pressure control valve when the cam switching type first valve operating characteristic changing mechanism has established a high-speed valve timing by supplying hydraulic pressure from a first hydraulic pressure control valve to the mechanism, the second hydraulic pressure control valve is brought into a neutral state to cut off hydraulic pressure from the oil pump, and an advancing chamber and a retarding chamber in the second valve operating characteristic changing mechanism are closed. Thus, it is possible to prevent the consumption of hydraulic pressure in the second valve operating characteristic changing mechanism to ensure hydraulic pressure supplied to the first valve operating characteristic changing mechanism.