Patent ID: 8035917

Claim:
A disk device comprising: a disk-shaped recording medium; a drive motor comprising a rotatable hub fitted with the recording medium, the drive motor configured to rotate the recording medium; a disk-shaped clamper which is attached to the hub and holds the recording medium; a head configured to record and reproduce information to and from the recording medium; and a head actuator configured to support the head for movement and cause the head to move with respect to the recording medium, wherein the disk-shaped clamper comprises a center aperture formed on a central axis of rotation of the drive motor and at least one positioning hole eccentric to the central axis of rotation, the disk-shaped clamper being fixed to the hub by a fixing screw driven into the hub through the center aperture, the hub comprises a support surface opposed to the disk-shaped clamper and an annular engaging groove formed in the support surface to be coaxial with the central axis of rotation and opposed to the positioning hole and the disk-shaped clamper, the engaging groove continuously extends in a ring shape around the central axis and is configured to be engaged with a fixing pin which is passed through the positioning hole of the disk-shaped clamper.