基于响应面法的机床床身动静态多目标优化

Dynamic and Static Multi-objective Optimization of Machine Tool Bed Based on Response Surface Method

为了提高数控机床的加工精度,床身必须具有较高的抗振动性,同时质量应尽可能的轻。文章基于SolidWorks建立TK6920型数控落地镗铣床床身三维模型,将模型导入ANSYS,对床身进行动态有限元研究,得到了床身前四阶模态固有频率和振型。在分析了模态结果后,提出以床身的质量和前四阶加权固有频率作目标函数、床身筋板厚度作设计变量建立数学模型,以确定床身结构多目标优化的最优解。从而使床身质量下降6.14%,前四阶固有频率分别提高8.54%、7.01%、6.99%、8.92%。为TK6920型数控落地镗铣床床身设计与制造提供一种理论指导。

To improve the CNC machine precision, the machine tool bed must have high anti-vibration performance, and its mass should be as light as possible. The 3D model of machine tool bed of TK6920 CNC milling and boring machine is created in SolidWorks. This model is introduced directly into the ANSYS to get the bed former fourth-order modal natural frequencies and mode shapes. According resuits, a mathematical model of the tool bed was built by taking the mass and the first four order natural frequencies of the tool bed as the objective functions and the thickness of stiffener plates as the design variables, which determined the optimal solution of the multi-objective optimization structure bed. So the tool bed＇ s mass was declined 8.00% in the quality pallet, and the first four natural frequencies were increased by 8.54% , 7.01% , 6.99% , 8.92%. The study provides a theoretical guidance for TK6920 CNC milling and boring machine bed＇ s design and manufacturing.