| 摘要 |
PURPOSE:To realize miniaturization by applying an electric field so that electromechanical conversion elements, which cause torsional deformation between the opposite end faces in the longitudinal direction upon application of the electric field, produce torsional deformation with different rates. CONSTITUTION:When rising B of voltage to be fed on lead wires 6a, 6b to piezoelectric elements 61, 62 is carried out in a short time, the piezoelectric elements 61, 62 produce torsional deformation abruptly. At that time, a shaft 5 and a lever 8 rotate in direction A whereas a weight 7 rotates in direction B thus sliding throttle vanes 29, 30. When the driving voltage is varied from C to A with falling rate D slower than the rising rate B, friction between the shaft 5 and the shaft hole 3a of a ground board 3, the lever 8 and the ground board 3, and the friction in a throttle vane unit causes the shaft 5, the lever 8 and the throttle vanes 29, 30 to stop and only the weight 7 rotates in the direction A through torsional deformation of the piezoelectric elements 61, 62. At a time point when the voltage returns to A, rotation of the weight 7 stops. The operation is repeated and the piezoelectric element 5, the weight 7 and the lever 8 are rotated in the direction A. |
