Patent ID: 8151750

Claim:
A valve operating device that opens and closes a valve of an internal combustion engine by driving a valve stem in an axial direction, comprising: a rocker cam that rocks in accordance with a rotation of a drive shaft which is synchronized with a rotation of the internal combustion engine, the rocker cam comprising a driving cam portion and a lift restricting cam portion; a cam follower that lifts the valve by contacting the driving cam portion slidingly so as to convert a rocking of the rocker cam into an axial direction motion of the valve stem; and a restricting member that prevents the cam follower from separating from the driving cam portion in cooperation with the lift restricting cam portion, the restricting member and the cam follower being formed integrally in a rocker arm; and a valve spring configured to bias the valve stem in a valve closing direction to maintain the cam follower in contact with the driving cam portion, wherein a gap is formed between the restricting member and the rocker cam in a state where the cam follower is in contact with the driving cam portion and disappears such that the restricting member and the rocker cam come into contact with each other only when the cam follower separates from the driving cam portion opposing a spring force of the valve spring.