Patent ID: 7418933

Claim:
A variable lift valve operating system for an internal combustion engine, comprising: a variable lift mechanism which includes a control shaft rotatably supported in a cylinder head to change a lift amount of an engine valve in accordance with rotation of the control shaft; and an actuator which is connected to the control shaft and which comprises an electric motor and a power transmission that is interposed between the electric motor and the control shaft, wherein the power transmission comprises a worm wheel, a worm gear in mesh with the worm wheel, and a deceleration mechanism disposed between the worm gear and the electric motor, and a default spring coupled to an end of the worm gear; wherein the worm wheel which is in mesh with the worm gear is connected to the control shaft; wherein the actuator is constructed to be an oilless structure without oil supply; and wherein at least one of gears which constitute a part of the actuator and which are in a pair to be meshed with each other is formed of a synthetic resin.