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:
Apr. 03, 2012
Filed:
Dec. 02, 2009
Yuichi Takemura, Toyohashi, JP;
Yuichi Takemura, Toyohashi, JP;
Denso Corporation, Kariya, JP;
Abstract
A variable valve timing control apparatus for an engine includes a variable valve timing unit, a lock pin, a hydraulic control unit, and a lock control unit. The lock control unit causes the lock pin to lock the camshaft phase at an intermediate lock phase when a lock request is issued. When the lock request is issued, the camshaft phase is shifted in a reference direction to go beyond the intermediate lock phase while the lock pin is urged in a lock direction. When the camshaft phase stops around the intermediate lock phase, the lock control unit changes a control amount of the hydraulic control unit by a certain amount to shift the camshaft phase. The lock control unit determines that the camshaft phase has been locked at the intermediate lock phase when the camshaft phase is not shifted even after the lock control unit changes the control amount.