Abstract: A light commercial vehicle new energy electric drive bridge, in the full load 6.5T, 30 000 km road durability test process, running about 6 000 kilometers, abnormal power interruption occurred. After investigation, it is found that the shell of the electric drive bridge reducer is broken in the area of the differential bearing mounting hole, and even some of the main reducer gear of the faulty product have broken teeth. The fracture of the shell is analyzed by scanning electron microscope and confirmed as overload fracture. Combined with the static strength simulation of the shell, the results show that the fracture source region is consistent with the region where the simulated stress of the shell strength exceeds the yield strength of the material. By optimizing the shell structure, the stiffness of the area is increased and the strain is reduced. Combined with simulation analysis and test verification, the performance requirements are met.

Key words: Electric drive bridge reducer housing; Housing strength; Fracture analysis; Simulation analysis

摘要： 一款轻型商用车新能源电驱桥，在满载 6.5T、3 万公里综合路况耐久试验过程中，运 行 6 000 km 左右发生异响动力中断。经过排查，发现电驱桥减速器壳体在差速器轴承安装孔 区域发生断裂，甚至部分故障品主减齿轮存在断齿等情况。通过扫描电镜对壳体断口进行分 析，确认为过载断裂。结合壳体静强度仿真，结果表明，断口的裂源区与壳体强度仿真应力 超过材料屈服强度的区域一致。通过优化壳体结构，提高该区域刚度，减少应变，结合仿真 分析与试验验证，满足性能要求。

关键词: 电驱桥减速器壳体；壳体强度；断口分析；仿真分析