動態可變澆口模具建置應用於射出成型品質之研究

Investigation on the Establishment of Dynamic Variable-Gate Mold and its Application to Injection Molded Part Qualities

王國瑞(Kuo-Jui Wang)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/博士(2018年)

https://doi.org/10.6840/cycu201800715

摘要

射出成型製程中模穴內熔膠各點的壓力、溫度與比容的變化會影響到產品品質，透過P-V-T監測技術直接以壓力及溫度感測器擷取模內壓力及溫度訊號；進一步分析運算後，以便得到更佳更穩定的產品，將是未來射出成型產品品質控制很重要的技術。
本研究中在模具上採用動態可變澆口的設計方案，並配合P-V-T監測技術，希望藉此探討熔膠通過澆口時產生不同的剪切熱及壓力損耗的歷程，並藉由不同的模具參數探討對產品品質的影響，以達到提升產品品質之目的。
研究結果顯示，當澆口厚度越厚越容易利用成型參數控制產品品質，且保壓壓力越好傳遞與維持，對產品品質的提升具有正面的效果。但當澆口厚度超過臨界值時，對產品品質的影響則沒有明顯的提升。而在動態可變澆口實驗，利用兩種不同澆口前進延遲時間的實驗結果，可得知澆口前進回壓確實有提升產品品質的效果，但延遲回壓的時間點是其中的關鍵要素。若回壓的時間設定在充填結束時進行，則會影響到保壓壓力效益；而在保壓結束時澆口尚未完全冷卻固化進行澆口回壓，對於產品品質提升的效果明顯優於在充填結束時進行回壓的效果。
最後在動態可變澆口配合P-V-T控制技術的實驗，從產品品質結果可知，動態P-V-T控制技術可得到最佳產品品質，其出口比容值與產品品質結果有直接關聯，而動態可變澆口，當澆口前進回壓可使壓力上揚，具有輔助保壓的效果。

關鍵字

動態可變澆口 ； PVT監測技術 ； 壓力感測器 ； 溫度感測器

並列摘要

The quality of injection molded product was affected by the pressure, temperature and the specific volume in each position during injection molding process, by applying the PvT monitoring technology, the data we get from pressure and temperature sensors can be analysis and transfer in to the PvT graph, which can control the quality of the molded product to achieved high quality mass production.
In this research, PvT monitoring technology and the moveable gate design which can control the thickness of the gate during molding process was applied in order to investigate the shear rate and pressure drop in different gate thickness during molding, on the other hand, the influence of molding conditions to the molded quality was also investigated.
The results show that, the more the thickness of the gate, the better the quality can be controlled by molding conditions, and also the better the compensate of the packing. On the moving gate thickness experiment results, using deferent delay time of gate moving can improve the quality of molded product, also the started time of gate return is the other key to control the quality, if the starts time was to late then the compensation of packing will be poor, if the started time was to early will also lower the compensation of packing since the gate was forces to be solidified.
In the last part, the quality of molded product can be improved by applied the PvT monitoring technology to obtain the best packing pressure and packing time and was proved that the quality of product was related to the end of the PvT curve during molding process. When the thickness of the gate is reduced which will cause the pressure raised. And it has the effect of assist packing.

並列關鍵字

Moveable Gate ； PvT Monitoring Technology ； Pressure Sensors ； Temperature Sensors

參考文獻

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