When a knob is operated, operating force is exerted on an operating point Pm of the manual switch and an operating point Po of the automatic switch from a pusher, and thus the manual switch and the automatic switch are pushed and turned on sequentially. In this case, since the height H of the pusher is set ‘0.9 times’ or more of the distance Lmo from the operating point Pm of the manual switch to the operating point Po of the automatic switch, the pusher has a vertically long shape. As a result, the operating force of the knob is influenced by the friction when the automatic switch is pushed and turned on. Therefore, the manual switch and the automatic switch can be pushed and turned on sequentially while using the automatic switch having small self-holding force Fo.