Patent · US Expired

Driving circuit for piezo-electric multimorph transducer

US4237399A · kind A · utility

58Cited by
12References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 13, 1978
Grant dateDec 2, 1980
Priority date
Expiry dateNov 13, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R17/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A piezo-electric transducer, such as, a bi-morph leaf, comprised of a pair of piezo-electric elements which are oppositely poled in opposite directions and interposed between inner and outer electrodes with each element being bonded to the other at the respective inner electrodes, is provided with a drive circuit applying a drive voltage across the outer electrodes, one of which is desirably grounded, for deflecting the transducer, and which clamps the voltage at the bonded together inner electrodes to a relatively small maximum value at least in response to a polarity of the drive voltage opposed to the direction in which one of the piezo-electric elements is poled so as to avoid substantial depolarization of at least that one element. The foregoing arrangement is particularly desirable in an apparatus in which a magnetic head is moved along a track on a magnetic tape or other record medium for reproducing information signals recorded in such track which the bi-morph leaf supports the head for deflecting the latter in a direction transverse to that along the track in response to the drive voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.