| 摘要 |
PROBLEM TO BE SOLVED: To decrease the variations of the sensitivity and the resonance frequency of a sensor, and to increase its sensitivity by thickening each one end part of two piezoelectric boards joined to form additional mass sections. SOLUTION: Both ends of two piezoelectric boards 1a, 1b joined so that the directions of polarization axes may be opposite to each other are thickened. And electrodes 4a, 4b out of chromium gold having a thickness of 0.2μm for example are formed continuously over both thickened end parts, on the principal surfaces of the piezoelectric boards 1a, 1b, and a mechanoelectrical converting element 100 of cantilever construction having an additional mass section 5 at its one end and having a supporting section 6 at the other end, is constituted. By forming the additional mass section 5 at a tip on the opposite side to the supporting section 6, in this way, a beam (the thin part) becomes easier to bend when accelerated, and it is possible to make strains generated inside larger even by an acceleration in a similar degree. Accordingly, a potential difference (a detected current value) generated between the electrodes 4a, 4b becomes larger, and it becomes possible to obtain a high sensitivity as a result.
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