Piezoactuator and drive circuit therefor
US6841919B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 2002 |
| Grant date | Jan 11, 2005 |
| Priority date | — |
| Expiry date | Aug 12, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N2/008
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A piezoactuator has a diaphragm, and the diaphragm has flat piezoelectric elements that oscillate in a longitudinal oscillation mode and a sinusoidal oscillation mode. A first electrode for detecting oscillation in the longitudinal oscillation mode, and a second electrode for detecting the amplitude of oscillation in the sinusoidal oscillation mode, are disposed on the surface of the diaphragm. When the piezoactuator is driven with a drive signal, the phase difference of a first detection signal output from the first electrode and a second detection signal output from the second electrode is detected. The frequency at which the detected phase difference becomes the maximum phase difference is then obtained, and a drive signal of a matching frequency is applied to the piezoelectric elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.