压电单晶扬声器低频性能的优化及实验研究

Optimization and Experimental Study on Low Frequency Performance of Piezoelectric Single Crystal Loudspeaker

压电扬声器因其压电谐振式工作原理而成为顺应电子设备小型化趋势的研究热点,但是由于低频性能不突出而限制了其应用。该文为了降低压电扬声器谐振频率,在分析压电扬声器低频振动原理的基础上,提出了基于弯曲振动模态的压电单晶切型计算模型,并通过计算确定了其优化切型;利用有限元分析法验证了切型对扬声器谐振频率的影响;制作了扬声器原型器件,并对其谐振频率进行了测试与分析。结果表明,该文计算得到的优化切型将压电扬声器的弯曲谐振频率降低了约10%,证明该文提出的切型判断方法能够有效降低压电扬声器的低频谐振频率。

The piezoelectric loudspeaker is becoming a hotspot under the trend of electronic devices miniaturization because of its piezo-resonance mechanism.However,the applications of piezoelectric loudspeakers are limited due to its low frequency performance.In order to reduce the resonant frequency of piezoelectric loudspeaker,based on the analysis of the principle of the low frequency vibration of piezoelectric loudspeaker,a calculation model of piezoelectric single crystal cutting orientation based on bending vibration mode is proposed and its optimal cutting orientation is determined by calculation.The finite element analysis method is used to verify the influence of the cutting orientation on the resonant frequency of the loudspeaker.A prototype of loudspeaker is fabricated and its resonant frequency is tested and analyzed.The results show that the optimized cut orientation calculated in this paper reduces the bending resonance frequency of the piezoelectric loudspeaker by about 10%,which proves that the proposed cutting orientation judgment method can effectively reduce the low frequency resonance frequency of the piezoelectric loudspeaker.