PIEZOELECTRIC OSCILLATION GYRO UTILIZING ENERGY CONFINEMENT OSCILLATION MODE

摘要

PROBLEM TO BE SOLVED: To provide a small and thin piezoelectric oscillation gyro having simple structure for connecting the I/O terminals without using any lead wire in which the driving circuit and the detection circuit are provided on a same substrate as an oscillation gyro and the defect of conventional piezoelectric oscillation gyro are eliminated. SOLUTION: The piezoelectric oscillation gyro utilizing an energy confinement oscillation mode comprises a first, second and third electrodes 11, 12, 13 located at respective vertexes substantially forming an isosceles triangle substantially in the center of one major surface of a piezoelectric plate 10 having polarization axis in the direction of thickness. The first electrode 11 is set at the position of top angle and the second and third electrodes 12, 13 are set at the positions of bottom angle. The second an third electrodes 12, 13 are connected, respectively, with first and second current detection circuits having imaginary grounding function. When an exciting voltage is applied to the first electrode 11 and the piezoelectric plate 10 is turned about an axis substantially orthogonal to the major surface thereof, the difference of output from the first and second current detection circuits is detected.