Patent attributes
A valve operating system that includes a drive shaft, a drive lever that is fixedly provided thereon and can pivot in a direction of movement of a valve body, a follower arm that is fixedly provided on the valve body, a link, a first connecting shaft that connects one end of the link and the drive lever, and a second connecting shaft that connects the other end of the link and the follower arm; in response to a movement of the valve body from a first position to a second position by pivoting of the drive lever, a center of the first connecting shaft approaches from one side a straight line connecting two centers of the drive shaft and the second connecting shaft, and after the valve body reaches the second position, further pivoting of the drive lever is carried out through a predetermined angle so that the center of the first connecting shaft moves to the other side of a dead point on the straight line. Thereby a valve body can be held at one position with hardly any dependence on the output of an actuator, thus greatly reducing the load on the actuator.
