机床横梁是机床的重要部件,横梁的刚性对机床的加工精度影响很大,为此,需要对横梁结构进行优化设计以获得良好的静、动态特性.设计了6种横梁筋板结构,初步筛选出4种筋板结构的横梁,并以横梁筋板结构、筋板厚度、上导轨支撑筋板倾斜角度为试验因素,以横梁质量、最大耦合变形、最大耦合应力、一阶固有频率为评价指标设计了三因素四水平的正交试验;采用灰色关联法和组合赋权法处理有限元分析数据,获得优化设计的最优参数组合.结果表明,横梁“井”型筋板结构,筋板厚度25 mm,上导轨支撑筋板倾斜45°设计为最优方案,与原设计方案相比质量减轻了466 kg,横梁总形变减少了7.36％,一阶固有频率提高了2.91％.拓展了正交试验、组合赋权-灰色关联法的应用范围,为其它机床零部件的设计提供了有益的方法参考.%The crossbeam is an important part of a machining tool.The stiffness of the crossbeam has great impact on machining accuracy;therefore,optimization design of the crossbeam is necessary to obtain good static and dynamic characteristics.Six kinds of rib structure were designed and were preliminary screened out four kinds of them.The orthogonal experimental method was carried out with three levels and four factors,which took the crossbeam's rib structure,the rib thickness,the angle of supporting ribs on guide-way as design variables,and took the crossbeam's quality,the maximum coupling deformation,the maximum coupling stress,the first-order frequency as objective functions.The Grey correlation method and the combination weighting method were used to process the data of finite element analysis to obtain optimal parameter combination.The results show that the crossbeam with "井" type rib structure,rib thickness of 25 mm,the supporting ribs on guide-way tilted 45° is the optimal solution.Compared with the original design,the beam deformation reduced by 7.36％ and the first-order frequency increased by 2.91％,while the mass reduced by 466 kg.
展开▼
