大型落地镗铣床工作台的设计与研究

I
中文摘要
大型落地镗铣床工作台的设计与研究
念， 对提取的筋格单元进行动态变量优化， 分析筋格结构参数对筋格固有频率的影响， 并对筋格结构参数进行优化，得到了理想的工作台筋格结构。 通过设计与研究， 完成 4000×5000mm 工作台静压导轨的结构设计， 得到了偏载 工况下静压圆导轨各油腔的压力和油膜厚度的分布规律。 对工作台的结构和尺寸进行 优化设计，提高了工作台的结构刚性和动态性能，减轻了工作台的质量。为工作台及 机床其他部件的优化设计提供了一种可行的方法。
III
ABSTRACT
Design and Research on the working table of Large Floor Type Boring and Milling Machine
table’s internal structure is innovatively improved （inheriting the traditional working table’s advantages and improving its shortcomings） to get a new rib structure of working table. With CAD software three kinds of working table’s geometry models of traditional structure and the improved structure are created. And it’s ready for the next design and research. （3） The geometry models of different working table are imported into ANSYS, and divided mesh and set the same boundary conditions and constraint loads to the models in the ANSYS. Then deformation nephogram, equivalent stress nephogram and the first six natural frequencies are obtained with the static analysis and modal analysis. With the comparative study of the results of finite element analysis, the rationality of the new working table can be proved. （4） With the shape optimization module of ANSYS, the working table’s material nephogram is obtained. By researching the material nephogram, the layout of the internal ribs and the position of sand holes are obtained. The concept of unit structure is introduced into the research to do the dynamic variables optimization of rib box unit, and to research the parameters’ influence on inherent frequency of the rib box unit. So a new and more reasonable structure of rib box is obtained. Through the Design and Research, physical design of the hydrostatic guideway is completed, and the change of the oil cavity pressure and oil film thickness when the position of unbalance loading changes is obtained. With the shape optimization of the working table, the working table’s rigidity and dynamic performance are all improved, the quality is reduced, which shows a feasible method of optimization design of machine tool’s structure. Key Words: working table, hydrostatic guideway, finite element analysis, shape optimization, dynamic performance, unit structure Written by: Jing Cong
关键词：工作台；静压导轨；有限元分析；结构优化；动态特性；元结构
作
者：靖
聪
来自百度文库
指导老师：陈再良
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Design and Research on the working table of Large Floor Type Boring and Milling Machine
ABSTRACT
Design and Research on the working table of Large Floor Type Boring and Milling Machine ABSTRACT
With the rapid development of manufacturing technology, the demand of product quality and machining precision in national defense, aerospace, shipbuilding, energy, transportation, engineering machinery, metallurgical and other industrial areas is higher and higher, the requirement of machine tool’s precision is also increasing day by day, especially for large and heavy machine tool. The dynamic characteristics of the structure of large and heavy machine tool have a great impact on the machine’s work performance, such as efficiency, stability and reliability. Thereby increasing its dynamic characteristics of the structure of large and heavy machine tool has become one of the most important research topics in the area of machine tool design. The design and optimization of the 4000× 5000mm working table is based on the 3000× 3000mm working table of the Large NC Floor Type Boring and Milling Machine （TH6918）, the machine tool's overall technical indicators and the design and research of hydrostatic guideway. The methods of the design and optimization are finite element analysis and structure optimization. This paper is about: （1） The basic theory of hydrostatic guideway and the selection principle of fuel supply system are Summarized and researched. By researching the TH6918 machine tool specifications, constant pressure closed hydrostatic linear guide and constant pressure closed hydrostatic round guide are determined to be used as the guideways of the working table, and the degign of hydrostatic guideway is completed. Relevant parameters of the round guide’s oil pads are highlighted analyzed on the condition of unbalance loading, and the change of the oil cavity pressure and oil film thickness when the position unbalance loading changes are obtained, laying a foundation for the researching of dynamic performances and the obtaining of reasonable Load range. （2） Equivalent mechanical model of the working table’s internal structure is built, and the merit and demerit of traditional working tables are analyzed. Then the working
硕士学位论文
论文题目
大型落地镗铣床工作台的设计与研究
研究生姓名 指导教师姓名 专业名称 研究方向 论文提交日期
靖
聪
陈再良教授 机械电子工程 先进制造装备与技术 2013 年 4 月
大型落地镗铣床工作台的设计与研究
中文摘要
大型落地镗铣床工作台的设计与研究 中文摘要
随着制造技术的飞速发展，国防军工、航空航天、船舶、能源、交通运输、工程 机械和冶金等工业领域对机加工产品的质量和精度要求越来越高， 对加工产品的机床 精度要求也日益提高， 尤其是数控重型机床的质量和精度越来越受到关注。而重型机 床结构的动态特性对其工作性能、效率、稳定性和可靠性等有很大的影响，因此提高 重型机床结构的动态特性已经成为机床设计领域的重要研究课题之一。 以 TH6918 大型落地镗铣床 3000×3000mm 工作台的结构为基础， 根据机床的整 体技术指标， 结合工作台静压导轨的设计与研究，利用有限元分析法和结构优化法对 4000×5000mm 的工作台进行优化设计。 （1）分析研究液体静压导轨的基本理论及供油系统的选型原则；结合 TH6918 机床的技术指标， 研究采用恒压闭式液体静压直线导轨和恒压闭式液体静压圆导轨作 为所要设计的导轨形式， 并完成静压导轨的设计；重点分析偏载工况下圆导轨油垫的 相关参数， 分析得出各油腔压力和油膜厚度随偏载位置的变化情况，找出工件摆放的 合理位置，为研究工作台的动态性能及确定承载范围奠定基础。 （2）建立工作台内部结构的等效力学模型，分析传统工作台的优缺点；对工作 台内部结构进行创新改进， 将传统工作台中不同的筋板结构进行融合，得到一种新型 的工作台筋板结构； 利用 CAD 软件对传统工作台结构和创新改进的工作台结构建模， 创建了三种不同结构的工作台模型。 （3）将建立好的工作台几何模型导入 ANSYS 中进行网格划分，对三种模型施 加相同的边界条件及约束载荷， 然后进行静力学分析和模态分析，得到不同工作台的 位移云图、等效应力云图以及前六阶的固有频率；对比有限元分析的结果，证实了创 新型工作台结构的合理性。 （4）利用 ANSYS 对工作台进行整体的结构优化，得到工作台可去除材料的分 布云图，由此得到工作台内部筋板的布置以及筋板上出砂孔的位置；引入元结构的概