Patent ID: 6195322
Filing Date: 2001-02-27
Classification: G11B

Abstract:
A disk drive device having a base unit provided with a disk rotating unit having a spindle motor for rotating a disk-shaped recording medium and with a head for accessing data in the disk-shaped recording medium, said base unit being mounted to a base unit holder through a damping member, comprising:rotational speed control means for controlling the rotation of said spindle motor to thereby control a rotational speed of said disk-shaped recording medium to a set value;disk distinguishing means for determining, in a state in which said disk-shaped recording medium is being rotated, whether said disk-shaped recording medium is an eccentric disk or an unbalance disk; androtational speed setting means for, when said disk distinguishing means has determined said disk-shaped recording medium as the eccentric disk or the unbalance disk in a state in which said disk-shaped recording medium is being rotated at a first rotational speed, changing said set value to a second rotational speed slower than the first rotational speed;wherein said disk distinguishing means includes:hold means for controlling said head so that said head track-jumps over an address position of the immediately preceding track each time said head comes to a predetermined address position of the track on said disk-shaped recording medium; andtrack-jump interval determining means for determining whether the interval of said track jump is constant;said disk distinguishing means distinguishes based on the result of determination by said track-jump interval determining means whether said disk-shaped recording medium is either an eccentric disk or an unbalance disk.