| 摘要 |
PURPOSE:To obtain left and right rotation which can be operated easily and is stable by supplying power to one of two piezoelectric elements and interrupting power supply to the other. CONSTITUTION:In a drive unit 1, two piezoelectric elements 1-a which expand and contract are paired such that one for forward rotation is placed at side A while the other for backward rotation is placed at side B, each independent drive body 1-b is placed at its one edge, and one U-shaped inertia body 1-c is attached to the other edge so that two piezoelectric elements 1-a are connected. When a pulse-shaped high-frequency voltage is applied only to the side A, the piezoelectric element 1-a at the side A expands in upper and lower directions and is displaced. This displacement is propagated to the drive body 1-b as a wave and advances in lower direction as Y, Y' longitudinal waves. The longitudinal wave Y' which advances toward a tip surface 1-b'' of the drive body 1-b crosses vibration at right angle and are synthesized, thus enabling the vibration to be in circular motion with vector velocity (X). Since a rotary circular plate 2 is pressed against a tip surface 1-b''', the rotary circular plate 2 moves from right to left due to the friction force, namely rotates to the left. |
