Patent ID: 9147828
Filing Date: 2015-09-29
Classification: H01L

Abstract:
1. A piezoelectric drive element, comprising: a composite ceramic that combines a first piezoelectric ceramic having spring characteristics such that its elastic constant decreases as a vibration speed increases, with a second piezoelectric ceramic having spring characteristics such that its elastic constant increases as a vibration speed increases; and external electrodes provided on side faces of the complex ceramics in a manner facing each other across the complex ceramics; wherein an AC electric field at and near a resonance frequency is applied to the external electrodes to drive the piezoelectric drive element, wherein the first piezoelectric ceramic is a PZT-based lead piezoelectric ceramic, BaTiO wherein a volume fraction of the first piezoelectric ceramic and second piezoelectric ceramic is adjusted to suppress resonance frequency fluctuation relative to change in vibration speed.