To rotate and drive a plurality of driven gears selectively to perform a plurality of operations by one motor.

When a motor (spur gear 18) rotates forward, a first one-way clutch is locked, a second one-way clutch rotates idly, a worm gear 26 attached to an output shaft of the first one-way clutch rotates, and a cam plate 30 rotates to select one jaw clutch among a plurality of jaw clutches 42A to 42E. The selected jaw clutch 42A is connected, but the other jaw clutches are disconnected. After that, when the motor rotates reversely, the first one-way clutch rotates idly, the second one-way clutch is locked, a bevel gear 34 meshing with a bevel gear of an output shaft of the second one-way clutch rotates, a center gear 36 rotates, and a drive side 44 of each jaw clutch 42A to 42E rotates. Consequently, a driven gear 12A only of the jaw clutch 42A which is connected rotates.