Piezoelectric motor having a pivotally mounted annular shaped housing

Abstract

A piezoelectric motor for rotating a shaft formed of a hard material and having a general circular cross-section which drives a load having preselected torque characteristics and a known frictional force which opposes rotation of the shaft and load is shown. The piezoelectric motor includes a piezoelectric translation apparatus which is operatively coupled to the shaft for producing incremental angular rotation thereof. The piezoelectric translation apparatus includes a base plate, an annular-shaped housing and a support pin which passes through an aperture in the housing enabling the support pin to pivotally attach the housing onto the base plate. The piezoelectric translation apparatus further includes a piezoelectric driver assembly having an engaging member, at least one piezoelectric driving element and a compliance means. A control circuit for selectively applying electrical signals to the piezoelectric driving element for expanding and contracting the same is shown. The piezoelectric driving element is responsive the electric signals for applying a driving force on the shaft through the engaging member wherein the driving force applied to the shaft is reacted to the housing against the restoring force applied on the housing by the compliance means.