振動板與平面揚聲器之研發

Development of Vibrating Plates and Planar Loudspeakers

10.7117/JSET.201112.0036

賴峯民(Feng-Min Lai)；范凱涵(Kai-Han Fan)；陳裕偉(Yu-Wei Chen)；吳孟諭(Meng-Yu Wu)

三明治振膜 ； 製造參數 ； 花樣 ； 聲壓曲線 ； 平滑 ； 最佳化方法 ； manufacturing parameter ； optimal method ； pattern ； sandwich membrane ； sound pressure curve ； smooth

科學與工程技術期刊

7卷4期（2011 / 12 / 01）

35 - 44

繁體中文

本文主要以振膜開發、激振器製作、懸邊選用、最佳化設計來開發一全音域三明治結構平面揚聲器。以預浸材碳纖維（或奈米碳管）為上下層與珍珠板（或巴沙木）為夾心層來製造成三明治振膜，可應用於大型平面揚聲器上，其振膜加勁花樣、重量、剛性會影響高頻音域與整體感度，尤其最佳振膜花樣設計可讓平面揚聲器的音頻範圍變更廣。本文使用有限元素分析與Fortran軟體撰寫最佳化程式，針對三明治結構平面揚聲器在20Hz ～20KHz之範圍來尋找最佳設計參數值（激振長度、振膜材質、塗佈面積、懸邊系統材質，振膜塗佈樣式），使得聲壓曲線達到平滑。最後由實驗測試的聲壓曲線與理論分析進行比較，以實驗結果證明理論分析模型及最佳化設計的正確性。

The primary purpose of this paper is to determine the optimal design method for manufacturing gamut planar loudspeakers by developing a membrane, producing the exciter, and selecting the surround. We used carbon fiber prepreg layers (or carbon nanotubes) and foam boards (or Balsa) to combine the sandwich membranes, which were then applied to the large planar loudspeakers. An optimal sandwich membrane, which includes a stiffed pattern, minimum weight, and stiffness, affects the high-frequency sound quality and sound pressure curve. We employed optimizing programs that used finite element analysis and Fortran software to determine the optimal design parameters (excitation length, diaphragm materials, coating areas, surround system materials, and membrane coating patterns) to ensure optimal sound quality and smooth sound pressure curves at 20 Hz to 20 KHz. The optimized manufacturing parameters were subsequently used to manufacture sandwich planar loudspeakers. During experiments, we measured the sound pressure curves to verify the value of the proposed theory. The experimental results were used to verify the accuracy of the proposed analysis and optimizing methods.