Valve operating system in internal combustion engine

摘要

An actuator is connected to one of components forming a power transmitting device capable of transmitting a power provided by a valve operating cam provided on a cam shaft, so that the actuator can drive an engine valve in a lift amount which is obtained by addition of a lift amount of the engine valve based on a cam profile of the valve operating cam and a lift amount of the engine valve based on the operation of the actuator. Thus, a portion of the lift amount of the engine valve is borne by the valve operating cam, whereby a valve-opening power borne by the actuator can be reduced, as compared with a system designed so that the engine valve is driven by only the actuator only. The amount of electric power consumed by the actuator can be smaller.