混凝土数控机床支承件组合结构设计与优化研究

Design and Optimization of Concrete Supporting Components for CNC Machine Tools

作为数控机床的基础件,支承结构在很大程度上决定了机床的性能,然而基于传统材料的机床结构的优化几乎已接近极值。针对这种情况,提出了一种基于混凝土的组合结构并应用在支承件中。以床身为对象,采用外部钢板、内部填充混凝土制作“三明治”式组合结构,并对导轨进行预埋和稳定性增强设计。首先对铸铁床身以及混凝土床身结构进行动、静力学分析和比较;其次以导轨的静变形为约束条件,对导轨的支撑结构进行优化设计以增强结构稳定性;然后对组合结构床身进行稳态和瞬态热分析验证其热性能。最后,将该方法应用到某卧式加工中心的床身设计与优化中。仿真结果表明:混凝土组合结构床身与原铸铁床身的静刚度基本接近,但动态性能、热性能有了显著提高,并且降低了成本,证明了该结构的可行性。

As the basis component of CNC machine tools,the performance of the machine tools is mainly determined by the supporting structure.However,the structure optimization of machine tools manufactured by the traditional materials is nearly to the extreme value.So,a composite structure manufactured by the concrete which is used for the machine tools′supporting parts is presented.As an example,the sandwich structure is used for the machine tools′bed,with the steel is used as shell and concrete as core,and the navigation is embedded and further optimal designed for improving the stability.Firstly,the machine tool bed manufactured by the traditional material and the new bed manufactured by the concrete are analyzed for the dynamics and static properties respectively via finite element method,and the results are compared further.Secondly,with the static deformation of the guider as constraint,the supporting structure of the guider is designed to improve the performance.Then,the thermal property of the composite structure bed was verified by the steady-state and transient thermal analysis.Lastly,the presented method is used to redesign and optimize the structure of a horizontal machine center bed.The results show that although the static-stiffness of the concrete composite structure bed is almost equal to the prototyping bed which with traditional material,but the dynamic and thermal properties are improved greatly with the optimization design,and the cost reduction.So the feasibility of the structure and the design method is further proved.