| 摘要 |
PURPOSE:To obtain an ultrasonic which facilitates smooth and efficient rotation driving even if an abnormal displacement such as eccentricity caused by a machining accuracy or an inclination to the left or the right exists. CONSTITUTION:A circumscribed rotary drum 3 is composed of a circular ring plate 3a which has a V-shaped cross-section. The circular ring plate 3a is so constructed as to have a required elasticity along its radial direction and have a rigidity along its rotating direction. Further, a laminar disc 3b is formed on the lower joint part of the V-shape into one piece so as to have a required elasticity along its left-right direction and have a rigidity along its rotating direction. A boss 3c and a shaft 3d are formed on a small diameter part into one piece. Those parts are unified with a driving module 1, etc. Moreover, a rim is provided along the circumferential part of the circular ring plate 3a having the V-shaped cross-section to form a circular ring and the area of a friction driving surface between the rotary drum 3 and the driving module 1 to obtain a long life. |
