634 コーン型圧電振動子の振動・音響特性

抄録

A piezoelectric speaker has some strong points compared with a dynamic speaker. It is easily made small and light due to its simple structure. Also, it is excellent in sound reproduction in the middle and higher frequency ranges. But it also has some weak points. For example, the sound pressure level in the lower frequency range is poor because of the amplitude of vibration being small. Up to now a great effort has been made to improve the performance of the piezoelectric speaker, but no definite solution has been found yet. In this paper, a piezoelectric vibrator unit with a conical shell structure is reported, and the vibration and acoustic characteristics are discussed through F.E.M. and B.E.M. analyses and experiments.