Variable Ventilzeitsteuervorrichtung für Brennkraftmaschine

摘要

A variable valve timing mechanism of an internal combustion engine varies the valve timing by varying the rotation phase of the camshaft (15) with respect to a reference rotation phase of the drive shaft (72) of the engine. The mechanism has a first rotation member (11) and a second rotation member (12). The first rotation member rotates in fixed synchronism with the drive shaft (72) and has at least one recess (114) therein. The second rotation member (12) is located within the first rotation member (11) and rotates integrally with the camshaft (15). The second rotation member (12) has a vane (122) within the recess (114). The vane (122) is movable between two walls of the recess and divides the recess into first and second pressure chambers (101, 102). Hydraulic fluid pressure causes relative rotation of the second rotation member (12) with respect to the first rotation member (11) by applying pressure to the first and second pressure chambers (101, 102) to move the vane. The mechanism further has a lock device (20). The lock device restricts the relative rotation of the second rotation member (12) with respect to the first rotation member (11) such that the vane (122) is kept between the two recess walls when the engine is cranking. The lock device (20) is released after the engine reaches a predetermined running condition.