| 摘要 |
PURPOSE:To make an easy and accurate adjustment of the head position against the deterioration with age, etc., by reading the alignment control signal out of the control track provided to a disk and then adjusting the position of head. CONSTITUTION:A head 4 reads a control track 11 provided at an alignment area 10 at the outer circumference of a data truck 9 of a disk 6. Then a counter 15 of a track controller 14 is controlled. Thus the counter 15 counts the clocks after an index 8 is read in accordance with the position of the head 4. This clock count value is compared through an arithmetic circuit 17 with the reference value given from a reference value circuit 16 in case the head 4 is at a correct position. Thus the initial position of the head 4 is automatically controlled. As a result, an easy and accurate control is possible for the position of head against the deteriora tion with age, etc. |
