Disk unit for conveying disks of different diameters

A disk unit wherein a disk inserted is loaded to the interior of the disk unit or a disk accommodated in the interior of the disk unit is unloaded to the exterior of the disk unit, the disk unit comprises:

• a plurality of arms configured to convey two types of disks different in diameter while supporting an outer periphery edge of each of the two types of disks;
• and
• a lift frame provided with a turntable and a clamp head configured to support and rotate the disk,
• wherein the plurality of arms include a first arm that extends above the lift frame until loading of a small-diameter disk by the plurality of arms carrying the small-diameter disk to a position corresponding to the clamp head is finished, then the first arm that is extended above the lift frame is retracted to a location where the first arm does not extend over the lift frame, the first arm being retracted before the lift frame starts to raise or when the lift frame starts to raise, and after the loading of the small-diameter disk is finished.