INVESTIGATION OF MECHANICAL RESONANCES IN THE STRUCTURES OF PIEZO-RESONANT DEVICES

Abstract

The paper considers methods for determining the natural resonant frequencies of quartz resonator designs and their influence on the natural resonant frequencies of the piezoelectric element. The resonant frequencies of a typical quartz holder-piezoelement design are calculated. The dependence of mechanical resonances on the design parameters of the quartz holder is established, and the limits of their numerical values ​​are determined. The analysis was carried out for the most common designs of quartz resonators. However, the presented method can be applied to other designs of quartz resonators. In the experiment, a multi-frequency mechanical effect was simulated in the range from 20 to 200 Hz. The results are presented in the form of a normalized spectral density of the signal of the test frequency detector for the fundamental and third harmonics. It is established that the most intense mechanical resonances are caused by the design of the quartz holder and are in the frequency range up to 250 Hz. The inherent mechanical resonances of the piezoelectric element are in the frequency range above 4000 Hz and have little effect on the vibrational stability of the quartz resonator as a whole. The system response for the first and third mechanical harmonics confirms a significant correlation between the deviations of the resonant frequencies under vibration loading conditions, despite the changes in vibration sensitivity within the range, which is due to the design features of the quartz resonator.