龙门机床横梁结构的轻量化设计

Lightweight Design to the Beam Structure of the Milling Machine

横梁是数控机床的关键部件之一,其静动特性的好坏直接关系到加工工件的几何精度和表面质量。其中,横梁自身内部筋板的结构布局对其性能起决定作用,因此,设计布局合理、尺寸最优的筋板非常关键。汉川机床厂在横梁整体尺寸不变的情况下将横梁a"米"字型筋板数从5增加到10得到横梁c,整体性能有较大的改进,但相应横梁的质量也有所增加。通过对横梁c进行有限元分析,得到静态变形参数和前四节模态振型;以横梁质量最小为目标,Y和Z方向变形位移、低阶固有频率为约束进行尺寸优化设计,得到筋板最优尺寸参数。在整体性能较好的情况下,横梁质量减小了5.05%,实现了横梁结构的轻量化设计。

h Beam is one of the key components of CNC machine tools, whose static and dynamic characteristics have direct re-lationship with the geometric accuracy and surface quality of the workpiece. Among them, the structure and layout of the inter-nal ribs of the beam play a decisive role; therefore, it is critical to design a kind of reasonable layout, optimal size of steelplate. Hanchuan machine tool plant gets beam C by increasing the number of type “m” of beam A from 5 to 10 under the cir-cumstances of the overall size unchanged, the overall performance of the beam has greatly improved, but the quality of thebeam also increased by nearly 6% correspondingly. Through the finite element analysis on beam C, the static deformation pa-rameters and its first four modal shape are obtained; conducting size optimization to the beam by taking the minimum quality astarget, displacement deformation of Y and Z direction and low-order natural frequency as constraints to get optimal size param-eters of the rib plates. In the case of a better overall performance of the beam, the beam quality would decrease by 5. 05%,thus the lightweight design to beam construction is realized.