| 摘要 |
PURPOSE:To make it possible to reduce the thickness of an optical disk unit by reducing the length in the axial direction, and increasing the outer size of a motor while avoiding the interference with an optical head with respect to the rotating drive mechanism of an optical disk medium in a replaceable type optical disk unit. CONSTITUTION:An optical disk 11 made of a thin magnetic material and having a center hole 11-2a is absorbed and held by a rotatable disk type permanent magnet 12-3 having magnetic poles with the polarity different from each other equally divided in peripheral direction being supported by a spindle with a small diameter being not interfered with an optical head for recording and reading optical information. In addition, a plurality of flat coils 13-2 are provided in opposite to the disk type permanent magnet 12-3 on the opposite side of the disk type permanent magnet 12-3 relative to the optical disk 11, an electric current is given to the flat coil 13-2, and then the disk type permanent magnet 12-3 and also the optical disk 11 are rotated and controlled to a constant rotating speed. |
