PURPOSE: To reduce the number of parts, and to shorten time required for disk loading by executing continuous mode transition according to the rotational phase of a cam gear by using one driving source.

CONSTITUTION: The operations of disk taking-out from the inside of a disk cartridge 100, disk transfer, and disk clamp are executed according to the rotational phase of one cam gear 23, and in addition, position detecting means 61a to 61d detect a first position where the disk can be transferred from the inside of the disk cartridge 100 and a second position where the disk 1 can be reproduced, and a mode switching means switches the transmission of rotation from the cam driving source to the cam gear 23 according to the output of the position detecting means 61a, 61d. Thus, the smooth operation and a simplified mechanism can be obtained.