US Patent 7793915 Valve drive device

A valve drive device includes a valve element for opening or closing the inflow port or the outflow port, a drive mechanism for driving the valve element, an abutting part which is provided in any operation member included between the drive mechanism and the valve element, and a restriction part for restricting rotation of the valve element by abutting with the abutting part. The valve element is rotated by the drive mechanism so that the inflow port or the outflow port is opened or closed, and one of the abutting part and the restriction part is formed of an elastic member.