汽車扣件之模擬分析

Fastener Simulation

林承瀚(Cheng-Han Lin)

指導教授 ： 黃秀英

國立臺北科技大學/機電學院/車輛工程系所/碩士(2011年)

摘要

零件在組裝過程中，需考慮零件材質並依規定之扭力值鎖緊，才能達到鎖附之目的。如果扭力值過大，易造成螺栓變形量過大導致零件損壞。反之；易使扣件(Fastener)失去維持組合件之夾緊力，產生噪音或鬆動的現象，此情況在車輛應用上頗為常見。
　　本論文針對車輛用扣件，以有限元素分析(Finite Element Analysis)作分析模擬，並將結果與實驗值比較。研究中用SolidWorks軟體建構扣件模型，HyperMesh作有限元素分析的前處理，LS-DYNA求解，HyperView與LS-PrePost作後處理分析。擷取線彈性範圍內之資料，設定扣件的適當鎖緊扭力值，並與實驗進行比對，驗證分析之準確度。
　　由研究結果得知，有限元素分析準確模擬扣件的行為，與實驗結果相合，未來可將此方法運用於其他扣件之扭力值探討，減少硬體實驗所需的成本與時間，期望成為扣件扭力值測試之標準流程。

關鍵字

扣件 ； 扭力 ； 有限元素分析

並列摘要

In vehicle engineering, fasteners are regular to be tightened with specified torque values. Over time under- or over-torqued fasteners could result in joint loosing or failure, and not be able to maintain proper clamp forces. These jointed assemblies could gradually loose up and introduce squeak rattles, vibrations or noises.
The purpose of the study was to use Finite Element Analysis to simulate and set up torque SPEC for automotive fasteners. A Computer Aided Design tool, SolidWorks, was used to create 3-D models. HyperMesh was for the pre-process, LS-DYNA for solver, HyperView and LS-PrePost for post-process. The angle and torque control are both considered in the simulation. Torque-angle signature curves were obtained from the analysis. The torque SPEC of the joint was determined using the linear region of torque-angle curves. The results were compared with experiments.
From the study, a good correlation between simulations and experiments was observed. This research demonstrated that finite element analysis could accurately predict the behaviors of fastener joints. It could be effectively used for joint torque SPEC setting analytically. With that, hardware cost and test time could be saved significantly.

並列關鍵字

fastener ； torque ； finite element analysis

參考文獻

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