板件彎曲成形回彈機制之研究

A study of springback mechanism in the sheet-metal bending process

柯盛夫(Therm-Hoo Ke)

指導教授 ： 陳復國

國立臺灣大學/工學院/機械工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01444

摘要

板金彎曲成形主要缺陷為回彈與組裝精度之問題。以有限元素法軟體針對V形與L形彎曲製程進行分析，以瞭解回彈產之機制與影響回彈之製程參數。在回彈改善方面，模擬現有改善回彈方法之成效性，並對現有改善法之回彈機制作個完整的分析。由回彈機制分析可瞭解到改善回彈的關鍵所在，並提出反向彎曲法(Inverse bending method)作為改善法，進行模擬分析與實驗驗證，結果證實反向彎曲法的確有改善回彈之作用。由模擬分析提供反向彎曲法之設計原理，可作為反向彎曲模具之設計準則。在精度研究方面，以彎曲裕度公式為基礎，並考慮長度變化量，對中性軸位置常數作修正，以期得能夠更精準的預估板材長度。而預估板材長度可作為工業界之應用。

關鍵字

有限元素法 ； 回彈 ； V形彎曲 ； L形彎曲 ； 彎曲裕度 ； 回彈機制

並列摘要

The main defects on bending of the sheet-metal forming are springback and accuracy of forming on shape fixation.Analyzing V-die bending and L-bending by using the software of the finite element method to understand the mechanism of bending and the parameters of affecting springback.On the part of reducing springback,research the availability of reducing springback methods on bibliographies and complete the analysis of springback mechanism for them.From the analysis of springback mechanism,we provide a new method on reducing springback-Inverse bending method,and confirm it is feasible.So, the design principle of inverse bending method can be as the reference on die of inverse bending method. On the part of accuracy of forming,based the bend allowance and length of change,modify the neutral axis offset to get more accuracy sheet-metal length before forming which is contributive for the industry.

並列關鍵字

L-bending, ； V-Die bending ； FEM ； springback

參考文獻

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