| 摘要 |
PURPOSE:To simplify a supporting method and to constitute a lens barrel to be compact by utilizing an ultrasonic motor whose driving source is a plate-like elastic body where bending vibration is generated by longitudinal vibration by means of a single phase power source. CONSTITUTION:When a power source part 18 is connected to a 1st piezo-electric body 12a, respective standing waves of the longitudinal vibration and the bending vibration induced by the longitudinal vibration are generated in the elastic body 10 of a vibrating body part, and elliptical motion which is rotation in mutually opposite directions in a state where a supporting point for supporting the elastic body is put between them is generated in the elastic body. Driving force in one direction on one side of the supporting point of the elastic body 10 is transmitted to a motion extracting means 20 which contacts with the vicinity of one end of the elastic body 10, and it ultimately drives the lens of a camera, for example, to an extending side. In the case that the power source part 18 is connected to a 2nd piezo-electric body 12b, the driving force in the opposite direction is generated in the elastic body of the vibrating body part. Therefore, the means 20 drives the lens of the camera, for example, to a lens receding direction. Thus, the supporting method is simplified and the lens barrel is constituted to be compact. |
