ALS BOVENTOONKWARTS TOEGEPASTE DIKTE-SCHUIFTRIL- LER.

摘要

A thickness-shear mode piezo-electric vibrator comprises a piezo-electric crystal operable in the thickness-shear mode, driving electrodes formed on opposed surfaces of the crystal, and an addition mass formed on at least one of the driving electrodes and positioned on the nodal line of a 3-fold harmonic vibration so that the frequency fo of the fundamental main vibration and the frequency f3s of the 3-fold harmonic vibration always satisfy the following relation within the practical application ranges of temperature and load capacitance; thereby effectively eliminating or preventing the "abnormal frequency phenomenon" which would otherwise occur due to the 3-fold harmonic vibrations.