PURPOSE: To prevent the generation of vibration sound due to torque variation arising from the chopping drive of a fan motor, especially, that of the starting time, by controlling the fan motor so as to continuously drive it with driving currents of different levels in regular sequence in the low rotation level of the fan motor.

CONSTITUTION: A microcomputer 11 that outputs command values for drive control responding to plural driving currents of different levels with respect to a fan motor 13 by digital signals in accordance with a specified starting characteristic at the starting time, and in accordance with gas volume control signals given by an automatic air-conditioner while driving is provided in an automatic air-conditioner for an automobile, and drives and controls the fan motor 13 with these output signals through a D/A converting circuit 12, an operation amplifier 15, and a driver 14. And, the voltage between both terminals A, A' of the fan motor 13 is fetched by a differential amplification circuit 16, and supplied to the terminal C of the operation amplifier 15 as a feedback signal to generate a driver signal in response to the difference between the input terminals of both terminals C, D from the operation amplifier 15.