| 摘要 |
PROBLEM TO BE SOLVED: To provide an angular velocity detecting apparatus of high sensitivity using a vibrating beam shaped to maximize sensitivity to angular velocity, by coinciding a resonant frequency in the direction of exciting vibration with a resonant frequency in the direction in which Coriolis force is generated, while eliminating mechanical coupling. SOLUTION: In the angular velocity detecting apparatus, a first lithium tantalate piezoelectric element 2 and a second lithium tantalate piezoelectric element 3, which are polarized in opposite directions, are laminated together to provide a bimorph structure vibrating beam 1 in the form of a rectangular solid, the vibrating beam 1 being supported at both ends. The vibrating beam 1 is shaped so that the value of thickness t of the vibrating beam 1 is greater than the value of width W thereof and the shape ratio W/t of the width W to the thickness t is not less than 0.864 nor more than 0.957. The vibrating beam 1 is frequency adjusted by laser trimming so that while mechanical coupling is avoided, the resonant frequency in the direction of exciting vibration coincides with the resonant frequency in the direction in which Coriolis force is generated. Thus, the vibrating beam 1 can be machined to have maximum sensitivity to angular velocity. |
