Abstract: A valve gear includes a valve (30), which controls a flow rate of a fluid and an opening of which is determined according to a rotational position of a valve element, an actuator (20) for providing a rotational force to a rotary valve shaft that changes the opening of the valve (30), and attaching/detaching means. The attaching/detaching means includes a locking element (32) formed at its prescribed positions with locking concave/convex portions and an engaging element (22) formed at its prescribed positions with engaging concave/convex portions. The locking element (32) and the engaging element (22) are relatively rotatable around the rotary valve shaft up to a prescribed angle, and prevent the actuator (20) from coming off the valve (30) at an engaging position where the engaging concave/convex portions and the locking concave/convex portions are engaged with one another, and allow the actuator (20) and the valve (30) to be detached from each other at a disengaging position.

Abstract: A valve gear includes a valve (30), which controls a flow rate of a fluid and an opening of which is determined according to a rotational position of a valve element, an actuator (20) for providing a rotational force to a rotary valve shaft that changes the opening of the valve (30), and attaching/detaching means for detachably attaching the valve to the actuator (20). The attaching/detaching means includes a locking element (32) formed at its prescribed positions with locking concave/convex portions and an engaging element (22) formed at its prescribed positions with engaging concave/convex portions. The locking element (32) and the engaging element (22) are relatively rotatable around the rotary valve shaft up to a prescribed angle.