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, 2003
Filed:
Oct. 23, 2001
Tatsuhiko Takahashi, Hyogo, JP;
Morio Fujiwara, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A valve timing control system for an internal combustion engine for preventing hitching of a lock pin of an actuator at the time of changing a cam angle is provided. The valve timing control system is provided with actuators and connected to cam shafts C and C, hydraulic pressure supply units and for driving the actuators, and a controller A for controlling a hydraulic pressure for the actuators in dependence on engine operation states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position, and an unlocking mechanism for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller executes a releasing operation of the locking mechanism if the lock-up position in the locking mechanism changes from inside a predetermined range to outside the predetermined range.