| 摘要 |
PURPOSE:To improve reading reliability of information by making an inner circumference part of track width of a magnetic disk larger than an outer circumference part. CONSTITUTION:When a magnetic head 3 is shifted from an outer circumference end part of a magnetic disk 2 to an inner P1 position, a stepping motor is driven by the step angle A deg., and when the head is shifted from a P1 position of a magnetic disk 2 to an inner P2 position, the motor is driven by the step angle B deg. (A<B). Further, to shift the head from the position P2 to an inner circumference part, the motor is driven by C deg. (B<C). While the magnetic head 3 driven by the stepping motor 11 is intermittently sent by a feeding quantity (a), (b) and (c) which by stages increases respectively in proportion to step angles A deg., B deg. and C deg. of the stepping motor in a surface of the magnetic disk 2, writing and reading are executed. |
