DISC DRIVER

PROBLEM TO BE SOLVED: To simply and smoothly return the positional relation between a slide member for transferring a drive force of a drive source to a head lift mechanism and a member at the drive source side for pushing the slide member to a normal state when a trouble occurs in the positional relation (abnormal state). SOLUTION: A geared motor as a drive source for operating a head lift mechanism has a cam disc 80 and a cam boss 81 protruding at an eccentric position from the rotary center of the disc 80, and a transfer member for transferring the drive force of the geared motor to the head lift mechanism is a slide member 109 which is located on the locus of a rotary motion turned approximately by a half revolution from an initial position A of the cam boss 81 and depressed in a direction by the boss 81 to slide. The slide member 109 has a surface depressed by the boss 81 and facing the cam disc 80, and this surface is formed into a slope (117b) apart further from the cam disc as going from the edge 117a depressed by the boss 81 to the opposite edge so that the cam boss 81 contacts the slope of the depressed surface when being rotated reversely to the depressing direction of the cam boss 81 to the depressed surface 117 (right piece).