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. 14, 1998
Filed:
Apr. 03, 1997
Kazuhisa Mikame, Nagoya, JP;
Tatsuo Iida, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
A variable valve timing mechanism of an internal combustion engine varies the valve timing by varying the rotation phase of the camshaft with respect to a reference rotation phase of the drive shaft of the engine. The mechanism has a first rotation member and a second rotation member. The first rotation member rotates in fixed synchronism with the drive shaft and has at least one recess therein. The second rotation member is located within the first rotation member and rotates integrally with the camshaft. The second rotation member has a vane within the recess. The vane is movable between two walls of the recess and divides the recess into first and second pressure chambers. Hydraulic fluid pressure causes relative rotation of the second rotation member with respect to the first rotation member by applying pressure to the first and second pressure chambers to move the vane. The mechanism further has a lock device. The lock device restricts the relative rotation of the second rotation member with respect to the first rotation member such that the vane is kept between the two recess walls when the engine is cranking. The lock device is released after the engine reaches a predetermined running condition.