Linear piezoelectric motor employing internal feedback
US5949177A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 1998 |
| Grant date | Sep 7, 1999 |
| Priority date | — |
| Expiry date | Jan 7, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N2/142
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A piezoelectric motor system is formed with a piezoelectric motor incorporating an element that is physically displaced as a function of an applied voltage resulting in the generation of a back electromotive force. The system incorporates a controller having an output connected to the piezoelectric motor. The controller receives a direction signal indicating the desired drive direction of the piezoelectric motor and a velocity signal indicating the desired velocity of the piezoelectric motor. The controller provides a drive voltage for driving the piezoelectric motor in the desired drive direction. An electrical equivalent circuit that mirrors the electrical characteristics of the piezoelectric motor is connected to receive the drive voltage from the controller. A comparator provides a difference signal indicative of the difference in voltage developed across the piezoelectric motor and the voltage developed across the electrical equivalent circuit. An integrating circuit receives the difference signal and provides a feedback signal to the controller. The difference signal is compared with the velocity signal to either increase or decrease the drive voltage applied to the piezoelec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.