積層製造技術經過多年研究與發展，以具有可製作複雜晶格結構和產品輕量化，且不失產品整體強度的優勢。本文將藉由此技術設計製作一款輕薄筆記型電腦內建音箱，來降低輕薄筆記型電腦內建音箱常發生因結構強度不夠，而造成機殼共振異音或中音谷的不良問題。
一般常見筆記型電腦內建音箱，分為塑膠殼上蓋和下蓋，組裝方式為將上蓋和下蓋通過超聲波壓合製程，使其形成一個內部密封的腔體，腔體內無晶格結構。而塑膠殼上蓋和下蓋是使用射出成形技術製造。本文則是以積層製造技術設計來製作音箱，且為了比較音箱內部有晶格結構和無晶格結構，對於距離微型揚聲器單體0.5公尺處聲壓分佈大小的影響，在繪製圖檔時，先將積層製造音箱外型尺寸和料厚，設計成跟塑膠成型音箱一樣，使其兩者差異只有塑膠射出成型音箱內腔為無晶格，而積層製造音箱內腔為有晶格，且晶格形式分為直孔陣列、斜孔陣列、三角型、四邊型、六角型和八邊型。然後再將3D圖檔、揚聲器單體T-S參數、電磁驅動力等相關變數，輸入COMSOL軟體進行聲學模擬。接下來，選擇COMSOL模擬性能較佳的晶格結構，利用積層製造技術來製作音箱，再量測頻率響應曲線和阻抗曲線數據，並比對有晶格結構、無晶格結構、真實量測和COMSOL模擬之間數據的差異，作為最終討論之依據。
　　實驗數據結果顯示，運用積層製造設計音箱內部結構，其直孔陣列比交叉斜孔陣列聲音表現好，而四邊型晶格比三角型晶格、六角型晶格和八邊型晶格聲音表現好，且與塑膠成型原設計音箱趨近。另外一般塑膠射出成型音箱內部均為中空設計，故使用積層製造音箱內部晶格設計，整體音箱結構強度會提升，機殼共振異音問題也會降低。最後，期望本文積層製造音箱設計，可作為未來相關音箱設計者的參考依據。

After years of research and development,Additive Manufacturing has the advantage of being able to produce complex lattice structures and lightweight products without losing the overall strength of the product.This article will use this technology to design and produce an Ultrabook internal speaker to reduce the undesirable problems of Ultrabook internal speakers that often occur due to insufficient structural strength, resulting in abnormal sound of the chassis resonance and midrange valley.
Common Ultrabook internal speakers are divided into a plastic upper cover and a lower cover. The assembly method is that the upper cover and the lower cover are assembled through an ultrasonic pressing process to form an internally sealed cavity without a lattice structure. The upper and lower covers of the plastic shell are manufactured using injection molding technology.
This article is based on the Additive Manufacturing design to make speakers, and in order to compare the internal lattice structure and non-lattice structure of the speaker, the impact on the sound pressure distribution at 0.5 meters away from the speaker driver. When drawing 3D files, first design Additive Manufacturing speakers to have the same dimensions and material thickness as plastic injection molding speakers. The difference between plastic injection molding speakers has no lattice, and Additive Manufacturing speakers have lattices,and the lattice forms are straight hole array, cross oblique hole array, triangle type, quadrilateral type, hexagonal type and octagonal type.Then input 3D files, speaker driver T-S parameters, electromagnetic driving force and other related variables into the COMSOL software for acoustic simulation.Next, select the lattice structure with better COMSOL simulation performance, use Additive Manufacturing to make speakers, and then measure the frequency response curve and impedance curve data,and compare the difference between the lattice structure and the non-lattice structure and the real measurement and COMSOL simulation as the basis for the final discussion.
The experimental data results show that using Additive Manufacturing to design the internal structure of the speaker, the straight hole array has better sound performance than the cross oblique hole array, and the quadrangular lattice has better sound performance than the triangular, hexagonal and octagonal lattices. Close to plastic injection molding design speakers.
In addition, the plastic injection molding speaker has a hollow interior design, so using the internal lattice design of the Additive Manufacturing speaker will increase the overall speaker structure strength and reduce the problem of cabinet resonance and abnormal sound. Finally, it is hoped that the internal lattice design of Additive Manufacturing speakers in this article can be used as a reference for related speaker designers in the future.

[1] 謝孟庭,從音箱內部設計探討揚聲器系統聲場變化關係,碩士論文,逢甲大學電聲碩士學位學程, 2014。
[2] LIU, Zhengqing, et al. Acoustic properties of multilayer sound absorbers with a 3D printed micro-perforated panel. Applied Acoustics, 2017, 121: 25-32.
[3] JIANG, Chaoyang; MOREAU, Danielle; DOOLAN, Dan. Acoustic absorption of porous materials produced by additive manufacturing with varying geometrics. 2017.
[4] NAZIR, Aamer, et al. A state-of-the-art review on types, design, optimization, and additive manufacturing of cellular structures. The International Journal of Advanced Manufacturing Technology, 2019, 104.9: 3489-3510.
[5] 材料擠製技術(FDM)製程資料，參考來源取自:
https://www.tiri.narl.org.tw/Publication/InstTdy_Full/2318?PubId=222
[6] 立體平板印刷技術(SLA)製程資料，參考來源取自:
https://www.tiri.narl.org.tw/Publication/InstTdy_Full/2254?PubId=219
[7] 數位光處理技術(DLP) 製程資料，參考來源取自:
https://www.tiri.narl.org.tw/Publication/InstTdy_Full/2254?PubId=219
[8] 黏著劑噴膠技術(BJ)製程資料，參考來源取自:
https://www.hubs.com/
[9] 疊層製造技術(LOM)製程資料，參考來源取自:
https://www.researchgate.net/figure/Schematic-diagram-of-the-sheet-lamination-process-Gibson-et-al-2015_fig4_334169112
[10] 指向性能量沉積技術(DED)製程資料，參考來源取自:
https://www.tiri.narl.org.tw/Publication/InstTdy_Full/2318?PubId=222
[11] KUMAR, Ajeet, et al. Design and additive manufacturing of closed cells from supportless lattice structure. Additive Manufacturing, 2020, 33: 101168.
[12] TAO, Wenjin; LEU, Ming C. Design of lattice structure for additive manufacturing. In: 2016 International Symposium on Flexible Automation (ISFA). IEEE, 2016. p. 325-332.
[13] NAZIR, Aamer, et al. A state-of-the-art review on types, design, optimization, and additive manufacturing of cellular structures. The International Journal of Advanced Manufacturing Technology, 2019, 104.9: 3489-3510.
[14] 杜功煥,朱哲民,秀芬,"聲學基礎",南京大學出版社,2001。
[15] 馬宜凡,微型揚聲器有限元素分析之探討,碩士論文,國立臺北科技大學車輛工程系所,2017。
[16] 蔡長安,微型喇叭音箱及出音孔之設計與分析,碩士論文,國立臺北科技大學車輛工程系所,2006。
[17] 劉玟伶,積層製造之彈性晶格結構設計分析與優化,碩士論文,國立虎尾科技大學機械與電腦輔助工程系碩士班,2019。
[18] COMSOL MULTIPHYSICS, User’s Guide, Version3.5a.
[19] HP Jet Fusion 3D 4200 Printer, User’s Guide.
[20] ProJet®3500 Max & 3510 Series 3D Professional Printer, User’s Guide.
[21] CLIO 11 STANDARD, USER'S MANUAL.