A piezoelectric motor operated under the superposition of the second and third bending modes of a sandwich transducer

Abstract

ABSTRACTA rotary piezoelectric motor was proposed, in which the second and third bending vibrations of a transducer were superimposed to produce reverse elliptical movements on the two driving tips. The second bending mode was used to overcome the preload, whereas the third bending mode was used to rotate the rotor. The frequency tuning process of the two bending modes was discussed. The working frequency, the maximum no-load speed, the maximum torque and the maximum efficiency of the prototype were tested to be 23.8 kHz, 130 r/min, 2.96 N·m and 16.8%, respectively.