VALVE TIMING CONTROL APPARATUS AND METHOD

摘要

A valve timing control apparatus (10) for a combustion engine is proposed, comprising a rotational member, preferably a sprocket (50), being driven by said combustion engine, a rotor (40) being mechanically coupled with a camshaft (42) for controlling opening and closing of cylinder valves of said combustion engine, a first configuration in which the rotor (40) is locked to the rotational member; and a second configuration in which the rotor (40) is unlocked from said rotational member, such that a switching phase of the valves in relation to said engine's rotational state can be controlled by an adjustable position between said rotational member and said rotor (40). In another aspect of the invention an operating method of said valve timing control apparatus (10) for adjusting a valve timing of a combustion engine is proposed. The variable valve timing control apparatus controls a relative rotation between a camshaft and an output shaft, which can either be prevented or permitted. A rotor being connected to said camshaft is releasably locked to a sprocket connected to said output shaft to thereby prevent relative rotation between the camshaft and the output shaft by a locking pin. The locking pin is driven by a hydraulic system which controls said cam phasing adjustment.