| 摘要 |
PURPOSE:To increase the efficiency and the torque of a motor by optimizing the material as well as the constitution of a head mass unit. CONSTITUTION:An ultrasonic motor is constituted of a stator 10, a rotor 18, a spring 21, contacting said both parts, and the like. The stator 10 is equipped with a supporting plate 13, a head mass 14, a rear mass 15, a bolt 16 for clamping and a disc type head mass 16 and forms a composite longitudinal- torsional oscillator having piezo-electric ceramics elements 11, 12 for driving longitudinal and torsional oscillation. The product of the density of the head mass 17 and the modulus of elasticity of the same is made larger than the same product of the head mass 14 while grooves are provided on the outer peripheral part with an equal interval. |
