| 摘要 |
PURPOSE:To improve angular speed detection accuracy by giving the same polarity to four driving piezoelectric elements provided to a vibrator and equalizing the natural vibration frequency of the secondary mode of a support rod provided with the detecting piezoelectric elements to the driving vibration frequency of the primary mode of the vibrator. CONSTITUTION:The four driving piezoelectric elements 5 are provided having the same polarity and a detecting piezoelectric element 6 is stuck on the support rod 3. Then the sectional shape of the support rod 3 is so set that the natural vibration frequency of its secondary mode is equal to the driving vibration frequency of the primary mode of the vibrator 2. Here, when AC voltages which are equal to the primary-mode natural vibration frequency of the vibrator 2 and has the same polarity are applied to the four elements 5, the vibrator 2 resonates to have the maximum amplitude in its breadthwise direction. When an angular velocity by rotated in a plane orthogonal to the cylinder center of a casing 4 is added to the vibration gyro 10, the vibrator 2 generates a Corioli's force in its thickness direction. This Corioli's force causes the support rod 3 to deforms by deflection in a horizontal surface, thereby causing vibrations in secondary mode. The deflection deformation of the support rod 3 generates a voltage across the element 6, so that the angular speed is detected. |
