射出成形模穴壓力感測器的安裝設計與研究

Study of Installation Method of Pressure Sensor for Injection Molding

張怡哲(Yi-Jhe Jhang)

指導教授 ： 林忠志

國立虎尾科技大學/工程學院/機械與電腦輔助工程系碩士班/碩士(2012年)

https://doi.org/10.6827/NFU.2012.00106

摘要

在各種生產製程上塑膠射出成形技術運用非常廣泛，不同產業對於產品品質的要求各有不同，產品品質的好壞往往受到製程參數的影響，以往的案例常藉由前人留下的經驗去做參數調整，然而這些參數卻有可能受外在因素改變而須作微調，但卻欠缺合適的工具，本研究希望透過壓力感測儀器做模穴的壓力變化監視，將得到的資料彙整利用找出影響關鍵的射出參數。本文重新設計一種測量模組的方法，設計合適的感測器安裝方式和位置，透過實驗去驗證此新方法的正確性。
實驗中使用聚丙烯(Polypro Pylene，簡稱PP塑料)在不同的射出參數對模穴壓力的影響，透過感測器擷取的壓力峰值與射出時間去計算出剪切黏度與剪切率，找出低、中、高的剪切黏度，並將實驗擷取到的資料和壓力曲線與文獻做比較，判別此種安裝方式和位置所得到的資料是否正確。依照低、中、高的射出速度做產品完整的充填，並透過感測器所擷取的壓力曲線做監視，最後將得到成品做衝擊試驗，判別低、中、高黏度造成成品強度的影響。此外，改變融膠溫度，同樣做產品體積95%的充填，驗證在相同的射出計量和射出參數，塑料黏度是否會提早趨於穩定。
經由實驗結果，本研究的壓力感測器安裝位置和方式其結果的正確性與傳統安裝在公模穴的方式相似，而且安裝與拆解過程的步驟也減少了，證實此種安裝方式和位置是可行的。

關鍵字

模穴壓力 ； 剪切黏度 ； 射出成形

並列摘要

Many products are made by injection molding method because of its efficiency in mass production. The mold design, material property and molding parameters are main factors that influence the molding quality. Some molding parameters are difficult to be investigated because molding process is proceeded during the mold is closed. Some experiential rules lack of sufficient information to demonstrate it scientifically. In this study, a novel installation method of pressure sensor is designed, which provides a convenient approach to pressure measurement.
A mold contains installed by two different locations of pressure sensor is prepared for verification the proposed method. One location of the sensor is designed in the cavity near the gate while the other is design on the spruve bushing. The material used in this study is Polypropylene. Three different melt viscosities, low, medium, and high viscosities are set to study the influence of melt viscosity on impact strength of the specimen. The results show that the proposed method have great potential for pressure sensor application.

並列關鍵字

pressure sensor ； melt viscosity ； injection molding

參考文獻

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