Patent attributes
A valve element opening/closing device may include a valve element for opening and closing an opening part, a drive mechanism for operating the valve element, and a motor for the drive mechanism. The drive mechanism may include a cam engagement part formed in the valve element, and a cam member rotationally driven by the motor. A cam face is formed in the cam member to be inclined to a direction of a rotation center axis of the cam member and engaged with the cam engagement part, and a turning preventing part restricting turning of the valve element is provided to move the valve element linearly. Further, the opening part may include a hollow pipe, a plate provided with a mounting hole into which the pipe is inserted, and a valve seat. The valve seat is provided with a projecting part and the brazing material is restricted to flow out to an abutting face of the valve seat by the projecting part.