Patent attributes
A lash adjuster for a valve gear includes a plunger movable upward and downward and including a high-pressure chamber, a leak path defined by an inner circumferential surface of a body and an outer circumferential surface of the plunger so that operating oil reserved in the chamber leaks through the leak path, and a ring-shaped member located between the body and the plunger. The member projects into the leak path during normal operation and is elastically deformed radially inward with increase in oil pressure at the chamber side so as to be retreated from the leak path when abnormal movement occurs in the valve gear such that oil pressure in the chamber exceeds a normal range, thereby reducing flow resistance of the oil in the leak path. The member has a surface receiving oil pressure in the chamber thereby to elastically deform the ring-shaped member radially inward.