摘要 |
PURPOSE:To rapidly allow positioning, by driving a motor by fixed effective input current corresponding to the rating current of the motor,in a method that positions a load, such as, a printing head, etc. at the desirable location by driving said load by turning the motor. CONSTITUTION:When a command signal corresponding to the quantity thetaM of the whole driving of a motor 1 is input from an input terminal 3, a 1st deviation detecting circuit 4 detects difference between the command signal and a signal of the angle of revolution fed from a detector 12 of the angle of revolution, and sends a deviation signal. The deviation signal is corrected to voltage V<1/2>1 by means of a correction circuit 5, and sent to a variable limiter 7. The limiter 7 changes over limiting voltage in response to output from a mode change-over circuit 6, limits V<1/2>1 within the limiting voltage and sends it to a 2nd deviation detecting circuit 8. The circuit 8 obtains difference with a speed feedback signal from a differentiation circuit 13, and applies a drive signal to the motor 1 through an intermediate amplifier 9, a fixed limiter 10 and an output amplifier 11. |