| 摘要 |
PURPOSE:To obtain a rotor for ultrasonic motor where following property for vibration of a stator is improved. CONSTITUTION:In a rotor 1, a ring-shaped protruding part 3 with a rectangular section is formed in one piece on a lower surface of an outer-periphery edge part of a thin disc 2 and at the same time a ring-shaped protruding part 4 with a rectangular section is similarly formed in one piece on an upper surface. A protrusion length of the ring- shaped protruding part 3 is nearly equal to that of the ring-shaped protruding part 4. An insertion engagement boss part 6 which is formed with an insertion engagement hole 5 where a rotor axis is inserted and engaged as a center is formed in one piece while it protrudes at both sides in a direction of rotor axis (upper and lower surfaces of the thin disc 2) and the protruding lengthy is made nearly equal. The protruding length y of the insertion engagement boss part 6 is equal to or less than the protruding length of the ring-shaped protruding parts 3 and 4. Since the insertion engagement boss part 6 is formed while it protrudes at both sides in a direction of rotor axis, rigidity can be improved, a vibration mode which is peculiar to the rotor cannot be generated easily, following property for vibration of the stator can be improved, and a large output, and a high efficiency of an ultrasonic motor can be achieved. |
