| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the occurrence of tap tone caused by an excessive difference between an advance limiting period and a retard limiting period when advance and retard of a timing valve are limited, respectively, in holding the valve timing in a specified period between the advance limiting period and the retard limiting period. <P>SOLUTION: A variable valve mechanism includes a holding mechanism 40 which separately includes an advance limiting mechanism 50 limiting a relative rotation on an advanced side of a vane rotor to a housing 22; and a retard limiting mechanism 70 which limiting a relative rotation on a retard side. The holding mechanism also holds a relative rotation phase in an intermediate phase by the cooperation of the limiting mechanisms. The variable valve mechanism further includes a phase adjusting plate 25 which is relatively and rotatable to a sprocket 21. While a relative rotation is limited by the advance limiting mechanism 50, the phase adjusting plate 25 is relatively rotated so as to be limited a reverse relative rotation to fix the phase adjusting plate 25 on the sprocket 21, and thereby the variable valve mechanism adjusts a state that the relative rotation phase is held in an intermediate phase. <P>COPYRIGHT: (C)2012,JPO&INPIT |
