考虑结合面特性影响的机床整机有限元静力学分析模型
Finite element static analysis model of machine tool considering influence of joint surface characteristics
王豪 1黄为彬 1方兵1
作者信息
- 1. 福建农林大学 机电工程学院,福建 福州 350002;福建省农业信息感知技术重点实验室,福建 福州 350002
- 折叠
摘要
针对机床数字化设计中典型结合面建模精度误差较大的问题,提出了一种采用虚拟材料等效结合面静力学特性的方法,建立了考虑结合面特性影响的机床整机有限元静力学分析模型,并完成了相应的静刚度测试实验.首先,综合考虑了弹塑性变形机制和摩擦力的影响,提出了一种新的结合面法向和切向刚度的分析模型;其次,根据不同类型结合面的特点,采用虚拟材料模拟结合面的刚度特性,建立了刚度特性与虚拟材料弹性模量和泊松比的关系,并将其应用于精密数控机床整机的静刚度分析;最后,开展了整机工艺系统的静刚度测试实验,得到了主轴末端X、Y、Z三个方向的刚度分别为 26.60 N/μm、41.87 N/μm和 40.17 N/μm,并将其与仿真数据进行了对比.研究结果表明:不考虑结合面影响的模型相对误差将近17%,而考虑结合面影响的模型相对误差在5%以内,验证了考虑结合面特性影响的机床整机有限元静力学分析模型的有效性;采用虚拟材料等效结合面静力学特性的方法可作为机床数字化设计的一种可行的方法.
Abstract
In the digital design of machine tools,there is a problem of large accuracy errors in typical joint surface modeling.To address this type of problem,a method that uses virtual materials to equivalently estimate the static properties of the joint surface was proposed.The finite element static analysis model of the whole machine tool considering the influence of the characteristics of the joint surface was established,and the corresponding static stiffness test experiment was completed.Firstly,a new analytical model for the normal and tangential stiffness of the joint surface was proposed by comprehensively considering the effects of the elastic-plastic deformation mechanism and friction.Secondly,according to the characteristics of different types of joint surfaces,virtual materials were used to simulate the stiffness characteristics of the joint surface,and the relationship between the stiffness characteristics and the elastic modulus and Poisson's ratio of the virtual materials was established and applied to the static stiffness analysis of the entire precision computer numerical control machine tool.Finally,the static stiffness test experiment of the entire process system was carried out.In the stiffness test experiment,the stiffness of the spindle end obtained through the experiment in the X,Y,and Z directions was respectively 26.60 N/μm,41.87 N/μm,and 40.17 N/μm,and the experimental data were compared with the simulation data.The research results show that the relative error of the model without considering the influence of the joint surface is nearly 17%,while the relative error of the model considering the influence of the joint surface is within 5%,which verifies the effectiveness of the finite element static analysis model of the whole machine tool considering the influence of the characteristics of the joint surface.The method that using virtual materials to equivalently estimate the static properties of the joint surface is a feasible method for the digital design of machine tools.
关键词
机床数字化设计/虚拟材料法/结合面静力学特性/静刚度测试/有限元静力学分析模型/弹塑性模型Key words
digital design of machine tools/virtual materials method/static properties of joint surface/static stiffness test/finite element static analysis model/elastoplastic models引用本文复制引用
基金项目
国家自然科学基金青年科学基金资助项目(51605091)
出版年
2024
NETL
NSTL
万方数据