PURPOSE: To smoothly and sorely eject even a heavy magazine, which houses a plurality of disks, by means of an ejection lever.

CONSTITUTION: An ejection lever 7 by a swing arm system is supported, so as to be turned freely, via a support shaft 12 installed so as to protrude from the rear surface of a chassis 5. A torsion coil spring 8 is laid between the ejection lever 7 and the chassis 5. In addition, a tension coil spring 14 which supports a limiter 13 so as to be turned freely and which energizes said ejection lever 7 in a magazine ejection direction is laid, at the support shaft 12, between the limiter 13 and the ejection lever 7. A lock release mechanism 20 is provided with a motor 21 and a gear 27 which is turned by using the motor 21. A first cam part 28 which projects and retreats a claw part 6a at a lock lever 6 on and from the chassis 5 is formed at the gear 27; a second cam part 29 which turns the limiter in the magazine ejection direction is formed.