塑膠射出成型內縮變形改善之研究

Abstract

本研究以USB隨身碟ㄇ型外殼，塑膠成型後所產生之內縮現象為研究的對象；試圖找出有效及快速的改善途徑，作為日後設計提升產品品質、降低開發時程及成本，並兼顧成品組裝後外觀效果為本研究之目的。 研究過程中分別從產品結構設計、CAE模擬分析、塑膠原料及參數等方面探討，並配合模具實機驗證其改善之結果。其中運用有限元素CAE分析軟體之MOLDEX 3D，試圖在設計階段發現其射出成型時可能遭遇的問題，快速檢驗零件及模具的設計是否合宜，找出成型之最佳化參數，先期預測製品可能發生畸變區域之結構加以預防及改善。模具實機實作方面，實際製作塑膠模具實驗之成品；實驗過程藉由2.5D投影、電子高度計、厚度檢測器及X-RAY等設備，量測成品發生內縮變形之前、中、後段尺寸，來驗證理論模擬分析的準確性。

This research focuses on the inwardly-bent deformation of plastic cases of USB flash drives after the injection molding. An attempt to find out an effective and fast solution was made to improve product qualities and to reduce the time and cost of product develop -ments, aiming at the appearance of the final product after component assembly. The factors of structural designs、CAE simulations、raw materials of plastic resin And molding parameters are discussed and then verified with actual tests of injection moldings. The finite-element-analysis software, MOLDEX 3D, was used for simulations of potential risks during molding process in the design stage, quick checks of part and mold designs, optimizations of molding parameters, and early predictions of defect zones to improve. As for the actual tests of injection moldings, an actual product was made via injection mold- ing process. 2.5D overhead projector, electrical height gauge, thickness detector, and X-ray equipmet are used to measure product dimensions before, during, and after the inward-bent deformations happened to verify the accuracy of simulation results.