| 摘要 |
PURPOSE:To give the stable servo control to the seeking action speed of a movable head of a magnetic disk by composing a speed signal after a harmful mechanical vibration component is satisfactorily attenuated by means of a secondary LPF. CONSTITUTION:The speed detection signal of a disk movable head obtained by a head movable part 102 and a speed detecting circuit 103 is mixed with the output of a gain matching element 6 obtained on the basis of the detection current of a servo current detecting circuit 104 through a mixer 8. Then a high frequency component is deleted by the secondary LPF3 together with a harmful mechanical vibration component. The speed signal having a low S/N and passing through the LPF3 is mixed with a servo current detection signal passed through a gain matching element 7 and the secondary BPF4 through a mixer 9. As a result, a speed signal containing no harmful mechanical vibration component is composed with a good S/N. Thus it is possible to give the stable servo control to the seeking action speed of a movable head of a magnetic disk. |
