Patent ID: 6903498

Claim:
A bimorph piezoelectric device comprising: a piezoelectric member having a first end surface and a second end surface arranged on two ends in the longitudinal direction thereof, an upper surface and a lower surface each extending between the first end surface and the second end surface, and a first side surface and a second side surface; and a plurality of first internal electrodes and a plurality of second internal electrodes being arranged substantially perpendicularly relative to the longitudinal direction of the piezoelectric member, being overlapped with each other via piezoelectric layers in the longitudinal direction, respectively, and being alternately arranged In the longitudinal direction; wherein each of the first internal electrodes having a first divided internal electrode and a second divided internal electrode divided substantially perpendicularly relative to the longitudinal direction of the piezoelectric member; each of the first internal electrodes has the same first shape and configuration and each of the second internal electrodes has the same second shape and configuration that is different from the first shape and configuration; and the piezoelectric member hiving a first piezoelectric region located on one of the first side surface side and on the upper surface side and a second piezoelectric region located on one of the second side surface side and on the lower surface side with respect to the center of the width direction of the piezoelectric member, the first and second piezoelectric regions being configured so that expanding/contracting driving-forces are generated 180° out-of-phase with each other, utilizing a piezoelectric longitudinal effect, whereby the bending vibration in which the entire portion in the longitudinal direction of the piezoelectric member is bent substantially perpendicularly relative to the longitudinal direction of the piezoelectric member.