某型数控车床床身结合面有限元建模及参数优化识别

Parameters recognition,opitimization and FEM modeling for jointing surface of a CNC lathe bed

在数控车床动态试验数据的基础上,应用有限元理论建立了机床床身底座结构的动力学模型,并应用有限元分析软件ANSYS5.7的参量化设计语言APDL(AnsysParameterizedDesignLanguage)编制床身底座结构有限元分析的命令流,利用软件提供的优化模块(DesignOptimizer)对结合面线性弹簧-阻尼单元的刚度值进行了参数优化识别.由此所建立的有限元模型较好地反映了机床的动力学特性,所获得的各阶固有频率计算值与动态试验的结果十分接近,最大相对误差不超过5%.因此,基于上述有限元动力学模型及动特性计算的结果,对于该型数控车床结构的进一步动态优化设计提供了重要的参考依据.

This paper firstly discusses modeling the CNC lathe bed with dynamic FEM based on some dynamic tests; secondly, it analyzes that batch file for CNC lathe bed is generated by using APDL (Ansys Parameterized Design Language); and also the parameters such as stiffness and damping of the linear spring damper elements between jointing surfaces of CNC lathe bed are recognized and optimized by applying ANSYS Design Optimizer software package; then, the dynamic characteristics of CNC lathe are calculated and analyzed, and error between theory value and tests is less than 5%; finally, an improved solution for CNC lathe bed is put forward. The result of the research based on FEM analysis would be a direct guidance to completely improve dynamic characteristics of this lathe. On the other hand, it could offer important references to dynamic design for same type of CNC lathe.