Patent · US Expired

Piezoelectric ceramic transformer being driven with thickness extensional vibration

US5241236A · kind A · utility

409Cited by
5References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 1992
Grant dateAug 31, 1993
Priority date
Expiry dateApr 1, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10N30/40

Abstract

A piezoelectric ceramic transformer comprises a low impedance portion 11 including a plurality of piezoelectric ceramic layers 111 to 115 having different thicknesses, a high impedance portion 12 and internal electrodes 16. The low and high impedance portions 11 and 12 are subjected to a uniform polarization treatment in a thickness direction and with the same vector of polarization. The low impedance portion 11 includes one or more piezoelectric ceramic layers having a thickness different from those of the other layers therein. No delamination of electrodes or breaking of ceramics occur upon polarization treatment. Therefore, a compact piezoelectric ceramic transformer for power source which has a high mechanical quality coefficient Qm and a high electric power transmission efficiency is provided.

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