DRIVING DEVICE OF RECORDING DISK

PROBLEM TO BE SOLVED: To provide a driving device of a recording disk capable of making the fine adjustment of a resonance point of a motor after the motor is completed. SOLUTION: The driving device of the recording disk that the end part of a fixing shaft 1 for the spindle motor fixed to a base plate 10 is fixed to a top cover 24 by screwing it down, is provided with a freely vertically movable sleeve 21 inserted for fitting to the upper part of the fixing shaft 1, a repulsive member 23 interposed between the sleeve 21 and the top cover 24, a bearing 3a having an inner ring 16 fixed to the sleeve 21 and an outer ring 17 fixed to the side of a rotor 4, and a mounting screw 26 screwed onto the fixing shaft 1 from the outside through the top cover 24 for adjusting the natural frequency of the whole assembly by changing the preload of the bearing 3a through the repulsive member 23.