| 摘要 |
PROBLEM TO BE SOLVED: To provide a stator especially effective for a hollow ultrasonic motor, capable of obtaining a stable vibration without requiring a highly-developed processing technique, and capable of transmitting vibration to the rotor with high efficiency. SOLUTION: A stator 11 is fitted with a vibrating board 12, an elastic ring 13, a piezoelectric element 14, and a hub 15. The vibrating board 12 has a first, second, and third bent parts B1, B2, and B3 from its stationary part 12b to its periphery. The elastic ring 13 is joined to the underside of the second bent part B2. The shape of the longitudinal section of the elastic ring 13 is a trapezoid. And the thickness of the external peripheral part of the elastic ring 13 is thicker than that of the internal peripheral part. |
