| 摘要 |
PROBLEM TO BE SOLVED: To reduce the drift of an angular velocity output by automatic return to a balanced point from change generated in an oscillation system by installing a differential type self-excited oscillation system which performs driving detection and amplifies vibrations in the orthogonal directions. SOLUTION: From an electrode of, e.g. a piezoelectric element 31 of a third leg 13 or a piezolectric element 23 of a first leg 11, a voltage signal is amplified with an amplifier QG1 so as to satisfy an oscillation condition and fed back to an electrode of a piezoelectric element 29 of the second leg 12 after the phase is adjusted with a phase shift circuit QP1. At the same time, from an electrode of, e.g. a piezoelectric element 33 of the third leg 13 or a piezoelectric element 37 of a fourth leg 14, a voltage signal is amplified with an amplifier QG2 so as to satisfy an oscillation condition, and fed back to an electrode of a piezoelectric element 27 of the second leg 12 after the phase is adjusted with a phase shift circuit QP2. As the result, the amplifiers QG1, QG2 and the phase shift circuits QP1, QP2 act as an oscillation circuit, and make third flex vibration oscillate as a self-excited oscillation having a frequency in the vicinity of frequency of the ideal fourth natural vibration of a vibration gyroscope of a four-leg tuning fork type. |
