Other

Essex-tec Corporation

Micro Pulse Systems, Inc.

Micro-pulse Research and Development

Charles W Staufenberg

Robert J Hubbell

John C Echols

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.

Piezoelectric motor having a pivotally mounted annular shaped housing

An electromechanical translation apparatus comprising a driven member which is adapted to be incrementally moved in a selected direction, and a piezoelectric multiaxis micropositioner adapted to produce incremental movement of the driven member in the selected direction wherein the micropositioner includes a mounting means, at least one piezoelectric driver assembly having a housing, an engaging member formed of a hard material having a selected driving end at one end thereof and a driven end at the other end wherein the engaging member's one end is positioned to selectively engage and translate said driven member in response to a driving force, and at least three piezoelectric driver elements positioned between the driven end of the engaging member and the housing wherein the piezoelectric driver elements are positioned in a spaced, angular relationship to the others and wherein each piezoelectric driver element is capable of separately responding to an electrical signal having a predetermined frequency and amplitude which varies between a first polarity and second polarity to expand and contract to change its geometrical dimension to apply a driving force on the engaging member which imparts an incremental movement to the driven member in the selected direction is shown. The use of an electromechanical translation apparatus as a piezoelectric multiaxis micropositioner for incrementally rotating a sphere having an optical element affixed thereto for use in an optical path is also shown.

Piezoelectric multiaxis micropositioner

An electromechanical translation apparatus adapted to produce incremental movement relative to a separate member and having a housing, a pair of clamping and translating members each of which has a driven end and an engaging end wherein each of the engaging ends is adapted to removably clamp and translate a separate member relative to the housing in response to a driving force which is selectively applied through the clamping and translating members to the engaging ends which selectively clamp the separate member at selected locations with a clamping force which varies with the magnitude of the driving force, a pair of piezoelectric driving elements operatively coupled one each to each of the clamping and translating members wherein each of the piezoelectric driving elements is capable of being selectively expanded and contracted in response to a voltage of a selected magnitude and selected frequency to produce between the housing and the clamping and translating members a variable driving force which varies between a first magnitude and a second magnitude and which enables the engaging ends of the clamping and translating members to apply a variable clamping force to the separate member which selectively clamps the members to the separate member for incremental movement therewith and enables sliding motion at conditions other than the selective clamping condition wherein the clamping force is a function of the magnitude of the driving force is shown. A method for producing relative translational movement between an electromechanical apparatus and a separate member is also shown.

Piezoelectric electromechanical translation apparatus and method

The high impedance output of a touch-sensitive piezoelectric sensor is coupled directly to the high impedance input of a CMOS (complementary metal oxide silicon field effect transistor pair). The CMOS is protected on its input side by clamps which restrict the voltage swing applied to the gates to within the range defined by the positive and negative CMOS bias supply (+V.sub.DD and -V.sub.SS). The sensor produces voltages of approximately equal magnitude in response to slow acting temperature changes and quicker acting manual touching. In order to distinguish piezoelectric from pyroelectric signals, the CMOS bias is periodically and briefly shorted, to ensure a brief return-to-zero of the sensor output, thereby effectively suppressing the slow acting pyroelectric signal without interfering with sensing of quick acting piezoelectric signals.

Growing community of inventors

Santa Barbara, CA, United States of America

Charles W Staufenberg