| 摘要 |
PURPOSE:To eliminate an adverse effect on a head performance due to a leakage flux from a DC motor by using the preload force of the bearing of a spindle shaft for a pressed contact between a friction plate and a piezoelectric driver. CONSTITUTION:A spring 72 is between a protruding part from a top end part of a housing 70 and the outer wheel of the bearing 71; and the outer wheel is pressed downward and preloaded by the spring 72. Meantime, the friction plate 74 is fixed on a rotor 73; and on a base 1 opposite to the friction plate 74, the piezoelectric driver 75 is arranged; and an ultrasonic motor is constituted of these components. Then, in the pressed contact by the friction plate 74 onto the piezoelectric driver 75, the driver 75 is actuated by the force of the spring 72 through the bearing 71, spindle shaft 53, rotor 73 and friction plate 74. Consequently, since the DC motor is not used, the adverse effect on the heads 14, 15 due to the leakage flux of the driving magnet of the motor is eliminated. |
