Abstract: A disc drive apparatus performing recording and/or reproduction on a disc-shaped recording medium in which the top plate of a body is in close proximity to the disc-shaped recording medium and the top plate is provided with air passages that extend in radial directions of the disc-shaped recording medium. This disc drive apparatus prevents floatation of the disc-shaped recording medium without causing cost increase.

Abstract: There is provided an iron core coil motor using an iron core coil, as a stator coil, formed by winding a coil winding around an iron core. Floating in the shaft direction of rotor is prevented with an attracting force generated by offsetting the center of magnetism of iron core of coil and the center of magnetism of rotor magnet and moreover the attracting force is set to 0.8 to 2.0 times the total weight of the rotating elements including rotor. Thereby, generation of noise and vibration can be controlled.

Abstract: Disclosed is a disk rotating mechanism equipped with an automatic aligning mechanism in which the number of parts is reduced and in which an improvement in assembly operability and a reduction in cost are achieved. The automatic aligning mechanism includes a case body made of a non-magnetic material and formed as a flat cylinder with one end surface closed, two or more balance members provided so as to be freely movable in the inner space (movement space) of the case body, and an attracting magnet adapted to attract the balance members when the rotating mechanism is at rest or rotating at low speed, wherein the case body is supported by the spindle shaft of a spindle motor and wherein the closed end surface (table portion) thereof serves as the table portion of a turntable.