基于转移质量方式的龙门加工中心动横梁结构优化设计方法

摘要

针对某大型龙门加工中心动横梁结构设计中存在一些部位材料余量过大、一些部位刚度不足的问题,提出一种以转移质量为核心的动横梁结构优化设计方法.方法是在对动横梁进行动静态性能分析的基础上,利用模态分析和拓扑优化技术辨识动横梁结构中的冗余质量,并将其转移到动横梁刚度不足的薄弱位置,设计出在不改变动横梁装配尺寸的前提下具有较为均衡动静刚度特性的动横梁结构方案.通过对改进前后动横梁结构的动静态性能参数的分析对比,改进后动横梁前4阶固有频率平均提高5.53％,整体方向最大变形量平均减少7.33％,表明该结构优化方法是有效可行的.%Since a gantry machining center's design of moving beam structure has problems like some parts have excessive materials and others lack of rigidity,the author proposed art optimization method,the core center of which is to divert the beam quality.Based on static and dynamic performance analysis of moving beam,this method uses modal analysis and topology optimization techniques to identify structural redundancy in moving beam weight, and then transfers the redundant weight to inadequate rigidity weak positions.lt is a more balanced scheme with the dynamic stiffness characteristics and doesn't change the assembly size of beam structure. Comparative analysis of static and dynamic performance parameters before and after the improved moving beam shows that the method increases natural frequencies of the lowqrfour orders by 5.53%, and at the same time reduces the total maximum deformation by 7.33% at average,which verifies the effectiveness of the structural optimization method.