| 摘要 |
PURPOSE:To miniaturize the title device by providing a roller bearing between a housing and a shaft held at the inside thereof and holding a ultrasonic motor. CONSTITUTION:A direct driving system rotary driving device provides a pair of deep groove type roller bearings constituted of inner rings 3, outer rings 4 and a plurality of roller 5 and provided with preload in case of assembly between th internal peripheral surface of a cylindrical housing 1 fixed to a body, etc., and a shaft 2 inserted into the inside thereof. At the internal peripheral surface of the housing 1, a step section 7 brought into contact with the internal surface of each of the outer rings 4 and an inward flange 8 are provided between the outer rings 4 constituting a said pair of roller bearings 6. Circular vibrators 9, electrostriction elements 10 and elastic substances 11 are orderly arranged and held respectively between both sides of the flange 8 and the internal surfaces of inner rings 3. Accordingly, the electrostriction elements 10 are energized, and oscillates vibrators 9 ultrasonically to rotate the flange 8 or inner rings or outer rings 4. |
