| 摘要 |
PURPOSE:To prevent previously the spread of injury due to exfoliated film powder, by inhibiting a shift of a head to a data zone if a contact start-stop zone is injured by the rub with the head of a magnetic disk device is started. CONSTITUTION:A signal is previously recorded to a contact start-stop zone 1 with a fixed frequency. A head 2 is set still on a disk 6 before the disk 6 revolutes. Then the disk 6 is revolved, and the number of revolutions reaches the prescribed value. The output of the floated head 2 is detected via an amplifier 3 and a waveform processing circuit 4. A circuit 5 checks whether the output of the above-mentioned detection is higher than the prescirbed level. When the detection output is larger than the prescribed value, a control circuit 8 drives an actuator to move the head 2 up to a desired position on a data zone 7. While the circuit 8 decides that the injury of the zone 1 exceeds an allowable range when the detection output is less than the prescribed value. Then it is inhibited that the head 2 is shifted to a position on the zone 7 by the actuator. |
