Patent ID: 8604665
Filing Date: 2013-12-10
Classification: H01L,H02N

Abstract:
1. Piezoelectric actuator, especially for an ultrasonic motor, comprising an acoustic oscillation resonator, characterized in that the acoustic oscillation resonator is substantially formed as a rectangular piezoelectric plate with two main surfaces, two side surfaces and two end faces and has a multilayer structure in its interior which represents layers of excitation electrodes taking turns with the layers of the common electrodes and the layers of polarized ceramic provided therebetween, with the polarization vector extending perpendicularly with respect to the surface of the electrodes, that all excitation electrodes are divided into two groups not connected to each other, which are disposed symmetrically with respect to the symmetry surface of the aforementioned plate, wherein this symmetry surface extends perpendicularly with respect to the main and side surfaces of the plate, namely through the center thereof, with each group of the excitation electrodes forming together with the common electrodes and the piezoceramic therebetween a multilayer generator for an acoustic wave which is arranged asymmetrically with respect to the symmetry surface of the piezoelectric plate; and wherein the common electrodes are comprised of two parts the configuration of which repeats the configuration of the excitation electrodes.