Piezoelectric Rotator and Micropositioner
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
Rotation from below 10-3 rad to an infinite number of revolutions with a torque of no less than about 10-3 Nm is often required in the positioning of samples at workstations for experimental and manufacturing purposes. The proposed rotator is based on the "slide'n ride" principle. A design using piezoelectric bimorphs is shown in Fig. 1. A ring 1 is connected to a shaft 2 by four bimorph bending elements 3, which are glued into slits in ring 1 and shaft 2. Shaft 2 is supported in a bearing 4 which has to provide a certain amount of friction (e.g., the thread of a micrometer screw). The piezoelements 3 are actuated by a sawtooth voltage. During the slow increase of the voltage, bimorphs 3 bend slowly, causing ring 1 to be rotated with respect to shaft 2 which rests immobile due to the friction in bearing 4.