| 摘要 |
PURPOSE:To increase the range of application of a rotary driving body, by a method wherein an annular oscillating element, generating the longitudinal wave of (n)th-order, higher than second-order, is employed to take a torque out of a standing wave. CONSTITUTION:An annular oscillating element 1 consists of ceramics electrostruction elements and is provided with a whole surface electrode 2 on one surface thereof while the other surface of the same is divided into four equal sectors and respective sectors are provided with split electrodes 3a, 3b. Further, the electrodes are polarized in the direction of the thickness thereof so that the directions of the polarizations of the neighboring sectors are reversed with each other. Piezo-electric laminates 5a, 5b are fixed on the partial surfaces of the whole surface electrode 2, corresponding to the split positions of the split electrodes 3a, 3b, through an insulation layer. Said piezo-electric laminate 5a is deviated clockwisely from a maximum amplitude position Y and the piezo-electric laminate 5b is deviated counterclockwise from the maximum amplitude position Y while the end face thereof is abutted against a driven body 10. According to this constitution, a voltage is impressed on the piezo-electric laminate 5a when the driven body 10 is rotated clockwisely while the voltage is impressed on the piezo-electric laminate 5b when the driven body 10 is rotated counterclockwise. |
