| 摘要 |
PROBLEM TO BE SOLVED: To provide a laminated piezoelectric element, wherein disturbance in waveform is reduced and reduction in oscillation is suppressed, and an ultrasonic motor which uses the laminated piezoelectric element to prevent the attenuation of displacement occurring in its stator. SOLUTION: An element 2 comprises a laminate formed by stacking at least three annular piezoelectric elements 4a-4e with their horizontally adjacent regions 61 -610 polarized in the renege direction of the thickness with internal electrodes in-between, so that their vertically adjacent regions are polarized opposite in the direction of the thickness, and external electrodes 8a, 8b formed on the uppermost face and lowermost face of the laminate. The external electrode 8a on the top, some of the internal electrodes, the external electrode 8b on the bottom and the other internal electrodes are connected with one another through through-hole electrodes in through holes 12 formed in the laminate. The through-holes 12 are positioned such that in proximity to the center of the ring in respective regions 61 -610 and they are in proximity to one end or both ends of the respective regions 61 -610 . |
