Patent ID: 7717073

Claim:
A variable valve actuation mechanism for use in a multiple cylinder engine, the variable valve actuation mechanism comprising: a plurality of variable valve lift mechanisms arranged in association with the cylinders of the engine to adjust the lift amount of respective valves of the cylinders, each variable valve lift mechanism including an end face; a control shaft extending through the variable valve lift mechanisms in an axial direction; an actuator for moving the control shaft in the axial direction and driving the variable valve lift mechanisms; a hollow shaft receiving the control shaft; and a plurality of collars fastened to the hollow shaft and arranged alternately with the variable valve lift mechanisms for determining the positions of the variable valve lift mechanisms with respect to one another in the axial direction, each collar including; a sleeve extending in the axial direction; and end portions formed integrally with the sleeve, at least one of the end portions directly or indirectly contacting the end face of an adjacent one of the variable valve lift mechanisms a plurality of supports for respectively supporting the collars, wherein each collar is supported by the corresponding support such that a clearance is formed between the end face of an adjacent one of the variable valve lift mechanisms and the corresponding support, the control shaft and the support holding the collar such as to restrict the sleeve from becoming eccentric while enabling movement of the collar in the axial direction.