平板電腦前蓋之翹曲分析研究

A Study in the Warpage of Tablet PC Front Covers

黃仕安(Shu-An Huang)

指導教授 ： 韓麗龍

國立臺北科技大學/機電學院/製造科技研究所/碩士(2012年)

摘要

平板電腦(Tablet PC)不僅需要具備像智慧型手機的輕巧及方便性，還必須有近似於筆記型電腦的強大硬體功能。為了同時兼顧硬體功能與產品外觀，大幅增加了機構設計的困難度。在7至10吋的平板電腦前蓋平均肉厚幾乎都在1 mm左右或更薄，以致模具設計、射出成形參數等都會影響產品變形及最終的尺寸精度。
本研究利用Moldflow模流分析軟體，探討平板電腦前蓋之翹曲變形。首先配合田口方法(Taguchi Method)進行L8直交表的干擾實驗，找出在干擾因子中影響翹曲變形比較顯著的關鍵因子。其次再利用L18內直交表與L4外直交表的配置(干擾因子)，進行優化的成形參數實驗。經由品質特性(Z軸翹曲)、S/N比與變異分析的比較，顯著影響的控制因子包含：澆口數量、融膠溫度、保壓時間、冷卻時間。利用此優化參數組合，CAE分析顯示其翹曲變形較原始製程參數有大幅改善。在實際射出的成品，優化參數在Z方向的翹曲變形也較原始設計優良。

關鍵字

平板電腦 ； 翹曲變形 ； 田口方法 ； 干擾實驗 ； 變異分析

並列摘要

A Tablet PC does not only possess the dexterity and convenience that likes a smartphone, also equips with powerful hardware as a Notebook does. Giving the consideration to hardware function and product appearance, it increases the difficulty of mechanism design. The average thickness of 7 to 10 inches Tablet PC is around 1mm or even thinner. Thus the mold design and injection molding parameter may affects on the product warpage and the finished-dimensional accuracy.
In this study, Moldflow analysis software was used to study the warpage and deformation of Tablet PC front cover. First, the noise experiments proceed by using Taguchi method and L8 orthogonal array to find the significant factor. Second, apply L18 inner orthogonal array and L4 outer orthogonal array to find out the optimal injection molding parameters. Through quality characteristics, S/N ratio, and variation analysis, results show the significant factors include the gate number, melt temperature, packing pressure, and cooling time. Using of the optimal parameters, the warpage was improved in compared with the original parameters by CAE analysis. In the actual injection molding products, the warpage in Z-axis direction is also better than original ones.

並列關鍵字

Tablet PC ； moldflow ； Warpage ； Taguchi Method

參考文獻

[18]程御賢，數位相框前框翹曲量之最佳化設計，碩士論文，國立臺北科技大學製造科技研究所，台北，2011。

[7]黃東鴻，薄殼射出件翹曲變形與殘留應力研究，國立成功大學碩士論文，2002。

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