摘要 |
To actuate a throttle valve, a first driving device is provided to drive the throttle valve only in a small throttle opening range, and a second driving device is provided to drive the throttle valve in a throttle opening range other than the small throttle opening range against a spring by using a throttle wire. The first driving device has a rotor and a magnetomotive force source. A magnet is provided on the rotor. Three pole pieces are provided on a peripheral edge facing the rotor. Pole pieces opposite to each other in polarity produced by the magnetomotive force source are connected by connecting magnetic paths. <IMAGE> |