| 摘要 |
PURPOSE:To execute positioning of a head easily and at a high speed by storing periodically servo-information written intermittently to a track, in a freely rewritable memory, and controlling a head positioning mechanism. CONSTITUTION:Servo-information 23, 24 is written intermittently in a servo-information pattern part 22 at every (n), (n)+10, etc. of 10 tracks of a data track part 21 of a rotary disk. Such information is reproduced by a recording and reproducing head and stored periodically in a freely rewritable RAM through a microprocessor. Basing on this stored contents, the microprocessor calculates a position of the track (n)+(m) having no information 23, 24, etc. in accordance with an expression {(a)+(b)}X(m)divided by 10, and controls a head positioning mechanism. In the expression, (a) and (b) denote positions of the tracks (n), (n)+1. Accordingly, it is unnecessary to read the servo-information of each track, and the head can be positioned easily and at a high speed. |
