Improvement of piezoelectric loudspeakers for radiation of low frequency signal
نویسنده
چکیده
Piezoelectric loudspeaker is characterized by its very simple constructions, but their radiation performance at low frequency region is poor because their conventional diaphragm is too stiff for large amplitude vibration. This paper proposes three innovative methods for improvement of low frequency radiation performance of piezoelectric direct-radiator loudspeakers by new constructions and materials.. The first model is a rectangular loudspeaker unit with a tuckshaped flexible diaphragm by a bimorph sheet of PVDF piezoelectric film. The second is a flat-shape unit using a new piezoelectric composite film by polymer and ceramic powder. And the third is a paper cone loudspeaker with a large radiator driven by continuous revolution of piezoelectric ultrasonic motors.
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