| 摘要 |
PURPOSE:To elilinate the high frequency component with causes the shift of a head position owing to the mutual interference, by inserting a through rate limiting circuit to a servocontrol circuit system. CONSTITUTION:A positioning device for an actuator 11a is provided with a speed control signal generating circuit 12a, a position error signal generating circuit 13a, a compensating filter 14a for stabilization of closed loop and a switch 15a which performs switching between the speed control and the position follow-up control. Then a drive current through rate limiting circuit 16a is added. The circuit 16a contains an operational amplifier 21 and a compensating terminal 213 connected with a capacitor 22 seving as a through rate limiter. The through rate of an output signal is limited since the value of a current I is limited by the peak current value in a through-in mode. The capacity of the capacitro 22 is controlled so that the band is reduced down to about several hundreds Hz when the input signal level is high. Thus it is possible to eliminate the high frequency component, i.e., the primary factor of the mutual interference. |
