電磁鄰近式感應加熱均勻性提升之研究

Study on Electromagnetic Proximity Effect for Improving Mold Surface Heating Uniformity

劉志鴻(Jhih-Hong Liou)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200562

摘要

目前3C產品對於產品外觀面高亮度特別講究且縮短成型週期以提高產量之需求。「快速動態模具溫度控制」於熔膠充填階段維持高模溫作充填並快速冷卻降溫達成成型之特性，可成功解決傳統射出成型品的常遇到的外觀問題如熔接線痕、浮纖等。藉由動態麼具溫度的控制可達成高亮度免噴漆等級外觀面需求且有效縮短成型週期達到經濟效益。
本研究利用高週波配合電磁鄰近感應效應，達成模具表面加熱均勻性提升之目標。第一階段，進行模塊內部有無嵌入式銅塊模塊測試加熱效率與均勻性，第二階段，選出最佳的模塊設計形式並測試在不同尺寸模塊表面積及模面距離下的加熱效率與均勻性，第三階段利用磁性材料對模塊進行區域性加熱的控制，希望可對特定的模塊表面積進行加熱，進而改善感應加熱上常出現的邊角效應並提升加熱均勻及加熱效率性且利用分析軟體相互驗證，第四階段利用分析軟體評估電磁鄰近感應加熱下，輸入不同電流以及頻率下，對於加熱效率的影響，對未來機台設計有一個更明確方向。
研究結果顯示，有嵌入式銅塊設計，最高與最低溫差高達21.47℃而加熱效率約4.1℃/s；無嵌入式銅塊設計最高與最低溫溫差相差4.25℃而加熱效率約3.3℃/s，模溫溫差降幅約72.9%；在加熱面積尺寸縮小4倍下，從3.3℃/s提升至6.6℃/s，加熱速率約提升約100%；無嵌銅式表面貼合磁性材料實驗模塊，在設計D1加熱效率約4℃/s並可達到控制加熱區域；設計D3加熱效率約4.5℃/s並可達到控制加熱區域以及解決邊角過熱的問題。從ANSYS®分析軟體，來進行模面溫度場模擬分析，其模擬分析與實驗結果趨勢相同，成功建立電磁鄰近感應加熱模擬分析技術，此技術具有可運用於雙面加熱及非平面加熱優勢。

關鍵字

高週波加熱 ； 鄰近效應 ； 加熱均勻度 ； 磁場控制

並列摘要

The current 3C products emphasize on high surface brightness and short cycle time for high output. High molding temperature can greatly contribute to the conventional method and advanced injection molded parts. Especially, it can meet the requirement of high-performance machine, special molding, high flow resin for thin-wall and micro/micro-feature molding processes.
The purpose of this study was to have a uniformly heated mold surface by the high-frequency induced electromagnetic proximity effect. At the first stage, heating efficiency and uniformity was tested with or without embedding copper block mold. In the second stage the best of mold design was selected. Then the heating efficiency and uniformity was tested by varying the surface area of mold and distance of the surface. The third stage aimed to control the heating area with use of the magnetic material. This stage focused on the specific surface area of the module, minimizing the corner effect due to induction heating and increasing the heating uniformity and heating efficiency, and to be verified with software analysis. The fourth stage was set to determine that input current or frequency had more significance over heating efficiency by evaluating the proximity effect in specific software, thus providing a more clear direction in machine designing.
As observed, in the embedded copper mold designing the difference between maximum and minimum temperature was up to 21.47℃with heating efficiency about 4.1℃/s; without embedded copper design such difference was up to 4.25℃with heating efficiency about 3.3℃/s. The mold temperature decreased about 72.9%.When the surface area was reduced by a quarter, the heating rate increased about twice from 3.3℃/s to 6.6. Meanwhile, the non-embedded copper-type surface fit magnetic materials mold, and reached the controlled heating area with a heating rate about 4℃/s in the D1 designing. In addition, the D3 designing, with heating rate about 4.5℃/s was able to reach the controlled the heating area and mitigate the corner effect. This Exp.eriment showed that ANSYS® can be used for Sim.ulation and give accurate result on the high-frequency induced electromagnetic proximity effect. This technique can be applied to double-side heating and 3D surface heating.

並列關鍵字

Magnetic field control ； Heating uniformity ； proximity effect ； high frequency induction heating

參考文獻

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