PURPOSE: To reduce the variance of stop position to stop an original scanner with high precision for every copy, by turning off the power source of a driving motor when the driving motor of the original scanner is switched from forward rotation to backward rotation.

CONSTITUTION: An original scanner 2 is returned at a constant speed V0 and enters reverse damping at a time t0, and driving of a motor 3 in the reverse direction is started. The forward rotation speed of the motor 3 is reduced rapidly and becomes 0 at a time t1, and backward rotation is started after the time t1. The motor 3 is rotated forward from the time t0 to the time t1 and the output of a D latch 6 is in the high level; but when reverse rotation is started after the time t0, the output of the D latch 6 is in the low level after the output pulse of a sensor 5b is inputted. A motor control circuit 7 turns off the power source of the motor 3 at this time (time t) by a switch means, and the motor 3 enters into mechanical champing. Since the power source of the motor 3 is turned off by the first pulse outputted from the photosensor after reverse of the motor 3, the time when the motor 3 enters mechanical damping is approximately uniform, and the scanner speed becomes very low, and the variance of stop position is reduced.