PURPOSE: To reduce the load applied to a solenoid during the operation by rotating a cam-driven plate to the position to close a control switch, sucking a rotary lever with the solenoid to hook it on the cam-driven plate, and holding the control switch at the closed state with the cam-driven plate.

CONSTITUTION: When the timer time is set with either an operating shaft 23 or an operating lever 52, a cam-driven plate 43 is rotated interlockingly with the operating shaft 12 or the operating lever 52 to close a control switch 40. A solenoid 21 is then excited via the control switch 40, and the suction operation of a rotary lever 25 is started. The rotation of the cam-driven plate 43 is completed before the excitation of the solenoid 21, and the solenoid 21 needs to suck the rotary lever 25 only. The load applied to the solenoid 21 is thereby reduced during the timer operation, and a large suction driving force is not required accordingly.