Method and apparatus for producing repeatable motion from biased piezoelectric transducers
US5568003A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | Sep 28, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/802
Abstract
A method and apparatus for producing a repeatable motion profile from a biased piezoelectric transducer (28) in which a first set of stored calibration voltage values corresponding to points in a predetermined voltage profile on the transducer (28) are retrievably accessed from a random access memory (20) by sequentially addressing (30,32,34) the memory (20) in order to drive the piezoelectric transducer (28) with the retrievably accessed calibration voltage values. Gain current values associated with motion of the piezoelectric transducer (28) at the same measurement points on the voltage profile associated with the stored values are measured (48,50,52) and compared against the stored calibration values and any differences are corrected for in order to produce the repeatable motion profile. The measurement points are preferably in a region of constant rate of change of voltage in the voltage profile, such as corresponding to the crossover point (54) in a motion profile of linear slope.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.