| 摘要 |
PROBLEM TO BE SOLVED: To obtain a piezoelectric vibrating gyro which is small and whose accuracy is high, by forming an insulating film for mass addition only in a vibration region, which is situated on the main face of a piezoelectric plate and which is surrounded by a first electrode to a third electrode and is which an energy confinement vibration is generated. SOLUTION: A first electrode 11 is installed on the main face in the central part of a piezoelectric plate 10, and a second electrode 12 and a third electrode 13 are installed in such a way that they are parallel to the first electrode and that they are separated from the first electrode by a prescribed distance. AN insulating film 17 which is composed of, e.g. SiO, MgF, frit glass or the like is formed on a vibration region surrounded by the electrodes 11, 12, 13 is order to add mass to the vibration region. When a driving voltage is applied across the electrode 11 and the electrodes 12, 13, a vibration in the X-direction is excited, the piezoelectric plate 10 is turned around the Z-axis, a vibration due to the Coriolis force is generated in the Y-direction, and an electromotive force is generated across the electrode 12 and the electrode 13. When the force is detected, a rotational angular velocity can be detected. Since the insulating film 17 exists in the vibration region, vibration energy is confined with a good efficiency, and a leakage vibration is reduced. Thereby, it is possible to obtain a piezoelectric vibrating gyro whose accuracy is high. |
