| 摘要 |
PURPOSE:To lengthen the life of a motor, by arranging magnets respectively face to face in the thrust direction and in the axial direction of a fixed bolster and rotation main shaft of the ultrasonic motor. CONSTITUTION:An ultrasonic motor is composed of piezoelectric elements 10 and 11, an elastic body 12, a lining material 13, a body of revolution 14, a fixed bolster 15, a rotating main shaft 16, ring-shaped magnets 17-20. In the radial direction of the rotating main shaft 16 and fixed bolster 15 on the circumference facing each other, by arranging magnets 17-18 respectively, the rotating main shaft 16 gets out of contact with the fixed bolster 15 and at the same time the axial dislocation of the rotating main shaft 16 in rotation can be prevented. In the thrust direction, to the position where the rotating main shaft 16 faces the fixed bolster 15, by arranging magnets 19-20 on each circumference, the pre-load between the body of revolution 14 and the elastic body 12 can be ensured. The contact position can thereby be reduced remarkably. |
