Patent ID: 6112711
Filing Date: 2000-09-05
Classification: F01L

Abstract:
An apparatus for controlling valve performance in an engine, the engine including a valve for opening and closing a combustion chamber, the valve being variably actuated so that at least one of a valve lift amount and a valve timing is varied, the apparatus comprising:a plurality of cams for selectively opening and closing the valve, the cams including a first cam and a second cam, the first cam having a profile differing from a profile of the second cam;a rocker arm arranged between the cams and the valve, the rocker arm having a contacting member for contacting the first cam;a guide bore formed in the rocker arm and having an axis;a cam follower reciprocally supported in the guide bore to contact the second cam, wherein the cam follower has an axis aligned with the axis of the guide bore and is capable of reciprocating movement in an axial direction;a lock member supported in the rocker arm and movable in a direction transverse to the axis of the cam follower, the lock member having an abutment surface movable between a first position spaced from the path of the cam follower and a second position located in the path of the cam follower, the lock member being disposed in the first position to permit reciprocation of the cam follower with respect to the rocker arm so that the valve is driven by the first cam through the rocker arm, and the lock member being disposed in the second position so that the lock member abuts against the cam follower and locks the cam follower to the rocker arm to drive the valve by the second cam through the cam follower and the rocker arm; anda supporting surface on the rocker arm to support the lock member when the lock member is positioned in the second position and is pressed by the cam follower, the supporting surface being opposed to the abutment surface of the lock member, wherein the supporting surface lies in an axial projection of the guide bore such that, when the lock member is in the second position, force is transmitted from the cam follower to the supporting surface through the lock member in the axial direction of the cam follower.