工具機結構設計與動態性能優化

Structural Design and Dynamic Optimization for Machine Tools

呂俊弦(Jun-Sheng Lu)

指導教授 ： 康淵

中原大學/工學院/機械工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100249

摘要

本研究探討工具機之結構設計及動態性能優化，針對複合式磨床及平面磨床，工具機結構由工作台、鞍座、軌道及底座構成，從每一個次結構的單獨分析開始，然後將次結構組合成整機，再作整機分析，以有限元素法，使用ANSYS軟體，探討其共振頻率、模態形狀等動態特性。
工具機引起振動的主要因素為外力激振與自激激振。工具機結構的振動會使工件表面產生波紋，若因結構設計不當，造成工具機在切削時產生不穩定的顫振。一個設計不良的工具機被製造出來以後，往往只能在極低的工作效率下才能切削出理想的工作表面，或切削出表面光滑度不佳的現象。外力激振造成的原因可藉人力改善完成，而自激激振造成的原因必須藉由結構設計改善完成。因此改善自激激振的先決條件，可藉由研究工具機整機的動靜剛度，以完成結構設計。在進行改善時，須藉由分析軟體進行，以便於建模、離散網格化、及求解。
因此，本研究使用商用軟體ANSYS來建立有限元素分析模型，離散網格化，求解工具機整機結構之動態分析，並據分析結果進行動態性能優化，以針對軟弱結構，改變設計使結構剛度強化。
關鍵詞：工具機、磨床、結構設計、有限元素方法、動態分析

關鍵字

工具機 ； 結構設計 ； 動態分析 ； 有限元素方法 ； 磨床

並列摘要

This investigation confers the structural design and dynamic performance optimization for complex grinder and surface grinder composed of bench, saddle, track and base. It confers the resonant frequency and the mode shape with finite element method by ANSYS from single analysis of substructure to complete structure formed from substructure.
The external excitation and self-excitation of machine tools lead to vibration. The vibration of structure will cause the ripple on the surface of work piece and the improper structural design will lead to unstable vibration as cutting. An improper designed machine tools will cost lots to reach demands. The effect caused from external excitation and self-excitation can be reduced by efforts and improving structural design respectively. Considering the static stiffness with ANSYS in favor of modeling, discrete meshing and solution improves the structural design.
Therefore, this investigation establishes the finite element model, discrete mesh and solving for the dynamic analysis of machine tools. The dynamic performance will be optimized due to the solution and the structure will be strengthened.
Keywords: Machine tools, Grinder, Structural design, Finite element method, Dynamic analysis

並列關鍵字

Dynamic analysis ； Machine tools ； Grinder ； Finite element method ； Structural design

參考文獻

[1] K. J. Bathe, 1982, "Finite element Procedures in Engineering Analysis, " Prentice-Hall.

[4] Daryl L. Logan, 1997, "A first course in the finite element method using algor, " PWS publishing Company.

[5] Saeed Moaveni, 1999, "Finite element analysis. Theory and application with ANSYS, " Upper Saddle River.

[6] Leonard Meirovitch, 1986, "Elements of vibration analysis, " A Simon & Schuster Company.

[10] Mlejnek, H., 1992, "Some Aspects of the Genesis of the Genesis of Structures, " Structural Optimization, 5月, 64-69.