Hydraulic valve timing adjusting apparatus

摘要

A hydraulic valve timing adjusting apparatus to be provided in a driving force transmission system for transmitting driving force to a camshaft with a cam for opening and closing an intake valve or an exhaust valve, comprising a housing assembly (11, 12, 14); a rotor (20) provided so as to be relatively rotatable with respect to the housing assembly; hydraulic chambers (31, 32) formed between the rotor and the housing assembly; a convex member (23) provided in one of the housing assembly and the rotor so as to be slidable therein; a recessed portion (21) provided in the other one of the housing assembly and the rotor so as to be engageable with the convex member; an urging member (24, 174) for urging the convex member toward the recessed portion; and an oil passage (25) which is able to supply oil pressure to the recessed portion; wherein when the oil pressure is supplied to one of the hydraulic chambers, the rotor is relatively rotated with respect to the housing assembly, and when the oil pressure is supplied to the recessed portion, the convex member is slidden in a direction opposite to the recessed portion to release engagement between the convex member and the recessed portion.