精密机床床身轻量化结构与性能协调设计研究

Research on Coordinated Design of Lightweight Structure and Performance of Precision Machine Tool Bed

针对机床床身结构与性能之间的制约关系尚不明确问题,提出明确的关系曲线以及合理的参数取值域;方法基于统计分析和灵敏度分析,对5种常见床身内部筋型进行研究,分析外壁厚度、筋板厚度、质量对结构动静态性能的影响,获得轻量化结构参数与结构动静态性能趋势曲线并指明关键尺寸变化对结构性能的影响规律,给出机床床身最优构型和结构轻量化设计建议;通过比较5种不同的机床床身筋型,得出米字筋构型的机床床身结构性能最优,其最大一阶固有频率为334 Hz,相比最差的V型筋床身结构一阶固有频率217 Hz,高出54%。并对其中一种筋型床身结构的前三阶固有频率进行仿真和实验对比验证,两者误差在5%范围内,证明了研究方法的有效性。

In view of the problem that the constraint relationship between the structure and performance of the machine bed is not clear,a clear relationship curve and reasonable parameter range are proposed.Based on the methods of statistical analysis and sensitivity analysis,the internal ribs of five common bed types were studied,and the influence of outer wall thickness,rib thickness,and mass on the dynamic and static performance of the structure was analyzed.In addition,the trend curves of the lightweight structure parameters and the dynamic and static performance of the structure were obtained,and the influence law of the key dimensions on the structural performance was pointed out.The optimal configuration of the machine bed and the suggestions for the lightweight design of the structure were given.By comparing five machine tool beds with different rib types,it is concluded that the structure performance of the machine bed with M-shaped rib configuration is the best,and its maximum first-order natural frequency is 334Hz,which is 54%higher than that of the worst V-rib bed with 217Hz.The first three-order natural frequencies of one of the ribbed bed structures are simulated and verified by experiments.The error of the two is within 5%,which proves the effectiveness of the research method.