| 摘要 |
PURPOSE:To prevent the occurrence of discharge, etc., in vacuum or special gas atmosphere, in an actuator which rectilinearly shifts the driving shaft as a spanworm by enabling the area between opposite driving piezoelectric elements for clamping being so arranged as to surround the drive shaft and capable of displacement in diametrical direction to be displaced in axial direction by means of piezoelectric elements for driving. CONSTITUTION:Piezoelectric elements 2 for driving and clampers 3a and 3b are surrounded by a cover 4, and the periphery of the exposed section of a mobile shaft 1 is covered with bellows covers 5a and 5b so that there may be no hindrance in the shifting of the mobile shaft 1. |
