| 摘要 |
PURPOSE:To eliminate the adjustment for each device as well as the position deviation regardless of the installing direction or the position of a head, by amplifying the error obtained by subtracting the speed signal from a speed estimating signal and adding the disturbance eliminating signal to the input of a power amplifier. CONSTITUTION:The acceleration of a servo motor is proportional to the current when no disturbance exists, and therefore the speed is proportional to the integration of current. This proportion is not satisfied if the disturbance exists, and therefore the disturbance is eliminated by adding a current proportional to the error to the motor. In other words, a loop which is applied to a power amplifier 1 from an error amplifier 9 via a gain matching element 10 works only to the disturbance which disturbs the main control. The output difference between a speed detecting means 7 and an integrator 8 is zero in an ideal state where no disturbance exists. Then the disturbance eliminating signal added to the amplifier 1 from the amplifier 9 via the element 10 is also zero. Thus the block of the integrator 8, the amplifier 9 and the element 10 gives no effect to the main control. When the disturbance exists, a difference is produced between outputs of the means 7 and the integrator 8. Then the disturbance eliminating signal is produced at the output of the amplifier 9, and the main control signal E receives no effect of disturbance. |
