某电动商用车车架轻量化改进

Lightweight improvement of the frame structure for an electric commercial vehicle

商用车车架是整车各总成以及零/部件的承载基体,而车架纵梁又是车架最主要的承重部件,为使商用车轻量化,从而满足市场对汽车低能耗、高效率的需求,以某电动商用车车架为研究对象,建立了车架有限元模型,采用结构设计的方法,对车架纵梁结构进行了重新设计。并对改进车架进行了尺寸优化设计,以车架纵梁和横梁的厚度为设计变量,以1阶模态频率、弯曲工况下加载点的最大位移和扭转工况下加载点的最大位移为约束条件,以车架质量最小为目标函数,对车架进行了尺寸优化。对传统车架和改进车架进行对比分析,分析结果表明,改进车架质量减少了174.40 kg(27.60%),在保证车架安全性能的同时实现了轻量化。

The commercial vehicle frame is the bearing substrate of vehicle assembly and parts/components, the longitudinal beam is the main bearing components of the frame, to make commercial vehicles lightweight and meet the market demand of low energy consumption, high efficiency for automobile, with a certain electric commercial vehicle frame as the research object, the frame finite element model was established, using the method of structure design, the frame longitudinal beam structure was redesigned.The improved frame was optimized with the thickness of rail and beam as the design variable, the first order modal frequency, the maximum displacement under bending condition and the maximum displacement under torsion condition as the constraint conditions, and the minimum mass as the objective function.The comparison between the prototype structure and the optimized structure shows that the weight of the optimized frame model is reduced by 174.40 kg(27.60 %),and the lightweight of the optimized frame is realized while the safety performance of the frame is ensured.