Piezoelectric devices and methods and circuits for driving same
US7969064B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2007 |
| Grant date | Jun 28, 2011 |
| Priority date | — |
| Expiry date | Aug 16, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/802
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.