PIEZOELECTRIC ACTUATOR AND METHOD OF DETECTING DISPLACEMENT OF PIEZOELECTRIC ACTUATOR

摘要

PURPOSE: To accurately measure the whole displacement of an extensible actuator using a piezoelectric element. ;CONSTITUTION: In a extensible actuator, which has a casing 5 and a rod 1 sliding inside the casing 5 and has a piezoelectric element between the casing 5 and the rod 1 and uses the piezoelectric element 4 equipped with a noncontact displacement meter 9 as a displacement detection mechanism and a displacement meter target 8, a flange 14 is provided at the end on the opposite side to the piezoelectric element support of the rod 1, and the displacement meter target 8 is attached to the top of the extension cylinder 6' attached to the cylinder 14, and the extension cylinder 6' is so arranged as not to be influenced by shrinkage or extension even if force works between the flange 14 and a fixed flange 15 on one hand. On the other hand, a strain gauge for measuring the strain of the constituent parts excluding the piezoelectric element is equipped on the rod 1, and the whole displacement of the actuator is obtained by substracting the displacement of the constituent parts excluding piezoelectric element 4 from the displacement of the piezoelectric element.;COPYRIGHT: (C)1993,JPO&Japio