五轴数控刀具磨床有限元分析及结构优化

Finite Element Analysis and Structure Optimization of Five Axis NC Tool Grinder

在考虑重力对机床加工精度影响的前提下,以特定构型五轴数控刀具磨床为研究对象,通过对其结构进行有限元分析,发现由于X溜板、Z溜板以及立柱设计的不合理,导致机床在竖直方向存在较大静变形,严重降低了机床加工精度。针对上述零件的不合理设计,将其分别作为优化对象,基于Topology Optimization拓扑优化、形貌优化以及尺寸优化方法,最终确定了X溜板、Z溜板以及立柱的优化结构及关键尺寸参数。优化结果表明,在保证机床静刚度不降低的前提下,整机质量减轻157.6 kg,同时优化后的机床在竖直方向最大静变形为-0.019 7 mm,相较于优化前减少11.66%。最后对优化前后机床的竖直方向定位精度及加工精度进行实验测量,结果表明,与优化前机床相比,优化后机床的竖直方向定位精度及加工精度分别提升约8.85%、5.9%。验证了所优化结构的有效性,从而使整机性能得到了一定提高。

On the premise of considering the influence of gravity on the machining accuracy of the machine tool,taking the five axis NC tool grinder with a specific configuration as the research object,through the finite element analysis of its structure,it was found that the unreasonable design of X slide,Z slide and column resulted in a large static deformation of the machine tool in the vertical direction,which seriously reduced the machining accuracy of the machine tool.In view of the unreasonable design of the above parts,they are taken as optimization objects respectively.Based on topology optimization,shape optimization and size optimization methods,the optimized structures and key dimension parameters of X slide,Z slide and column are finally determined.The optimization results show that,on the premise of ensuring that the static stiffness of the machine tool does not decrease,the overall weight of the machine tool is reduced by 157.6 kg.At the same time,the maximum static deformation of the optimized machine tool in the vertical direction is-0.019 7 mm,which is 11.66% less than that before optimization.Finally,the vertical positioning accuracy and machining accuracy of the optimized and pre optimized machine tools are tested.The results show that the vertical positioning accuracy and machining accuracy of the optimized machine tools are improved by 8.85% and 5.9% respectively compared with the pre optimized and pre optimized machine tools.The effectiveness of the optimized structure is verified,and the overall performance is improved to a certain extent.