模具快速冷卻搭配感應加熱溫控技術應用於 射出成型品變形量改善之研究

Study on the Rapid Cooling with Induction Heating Temperature Control (IHTC) Technology and Its Effect on the Warpage of Injection Molded Parts

黃文昭(Wen-Chao Huang)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6840/CYCU.2009.00777

摘要

由於綠色節能製造與產品外觀要求的提高，達到產品表面高亮度與不噴漆之先進成型技術為當下主要的發展目標。其中，模具溫度的控制為成品尺寸精度與生產效率的重要條件之一。「快速動態模具溫度控制」於熔膠充填階段維持高模溫並於充填結束後快速冷卻降溫，可成功解決傳統射出成型品的常遇外觀問題，並達成高亮度免噴漆等外觀面需求。感應加熱技術(IHTC)具快速提升模具表面溫度之優點，但其造成公母模面溫度差異而使產品翹曲變形之問題仍須克服。
本研究目的為探討感應加熱技術搭配冷卻水溫度控制對產品變形量之影響。實驗中控制模溫機公母模溫差(-50℃、0℃、50℃、60℃、70℃) ，冷卻水溫度20℃、母模冷卻水進入模具時間從充填開始後(1.0s、1.45s、3.45s、6.45s)，並搭配加強水道設計之外部感應加熱模具，探討不同參數對產品翹曲變形之影響，同時利用電腦輔助分析模擬變模溫過程行為並與實驗結果比較，以驗證分析之可行性。
實驗結果顯示，母模冷却水溫度20℃、冷却水在充填開始後1.45s進入以及公模溫度達80℃時，可使產品變形量由2.45mm改善到變形量0.03mm，成功將變形量改善99.78%。由實驗與分析結果顯示，冷卻水溫度、進入冷却水時間點、公模溫度是影響變形重要因素並證實分析之可行性。本研究利用冷卻水快速冷卻母模而達到公母模溫度平衡以有效改善成品變形量，具體應用冷卻水改善翹曲變形問題，預期可提升動態模具溫度控制技術應用範圍。

關鍵字

快速加熱冷卻 ； 變形量 ； 感應加熱 ； 射出成型

並列摘要

Due to various requires of green manufacturing and high quality product surface design. The painting free, no welding line and high gloss surface quality plastic product has become the most important purpose of advanced molding technology. It’s well known that high mold temperature technology may provide great contributions to solve these problems. However, the following issue is the obvious increasing of cycle time. The new development, dynamic mold temperature control (DMTC) technology, is the only way to reach the high mold temperature molding and without increasing cycle time. Induction heating combine with cooling water temperature control (IHTC) is the most suitable way among DMTC to get high heating and cooling rate for the only mold surface temperature control.
Generally, the operation of induction heating is only heat core side for eliminating the welding line on the part’s surface. The following issue is the serious warpage caused by the different filling mold surface temperature between core and cavity. The purpose of the study is to solve the warpage problem by using water cooling operation. The experiment mold with high efficiency cooling channels was established. Various setting temperature between core and cavity is -50℃, 50℃, 60℃, 70℃ and 0℃. The cooling water control valve was closed during the surface heating period and opened when packing start. Valve open delay time is calculated from the injection begin. Various delay time setting for experiments is 1.0s, 1.45s, 3.45s and 6.45s. Finally, the Moldex3D and Moldflow simulation were used to verify the warpage result and comparison with experiments.
As the results, the temperature different between core and cavity is the most effective molding parameters for the warpage reduction. The warpage can be reduced from 2.45mm to 0.03mm by setting the cavity and core temperature on 20℃and 80℃, respectively. The improvement is about 99.8%. The simulations result can well match with the experiments. By controlling the cooling balance of core and cavity may solve the shrinkage/warpage problems in induction heating mold temperature control and improve the application field.

並列關鍵字

warpage. ； rapid heating and cooling ； injection molding ； Induction heating

參考文獻

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