| 摘要 |
PURPOSE:To simply position a movable body with high precision by loading a nut screwed into a feed screw onto a movable body which slides on a basic board, through a preloaded load member and a piezoelectric element, and apply ing elongation onto the piezoelectric element by applying a voltage. CONSTITUTION:A nut 8 is supported onto a movable body 6 and pressed and nipped between a preloaded leaf spring 9 having steel balls 10 and 11 buried and a piezoelectric element 16 supported onto a piezoelectric-element press 13. The revolution of a pulse motor 5 is transmitted to a feed screw 3, and the nut 8 applies a feed onto the movable body 6 by shifting right and left, and said movable body 6 reaches the vicinity of a prescribed position, and a pulse motor is stopped, and rough feed is completed. When the step-shaped voltage in each 2.5V is applied onto the piezoelectric element, the elongation in an average value of 0.0075mum is generated at each 2.5V. Since, in this case, the nut 8 is screwed into a feed screw and does not shift, the movable body 6 is fed rightward with the higher resolving power than that due to the pulse motor. |
