目的 对屋顶盒包装机的顶部封口机构曲臂进行优化设计。方法 首先，通过ADAMS求解初始曲臂在工作时的极限载荷，利用HyperWorks中OptiStruct模块对初始曲臂进行准静态分析，得到模型应力云图与位移云图，根据分析结果确定基于相对密度法的结构优化模型。然后，应用OptiStruct创建以最小体积为目标函数的全局响应，以最大应力和最大位移为约束条件的、与子工况相关的响应，从而进行拓扑优化。最后，利用ABAQUS对优化后的模型和连接件进行非线性有限元分析校核。结果 优化后模型的质量减少了0.67 kg，最大应力值为48.71 MPa，位移最大值为0.04 mm。结论 对封口机构曲臂进行拓扑优化设计可行，不仅可以减少质量成本，也能满足结构的刚强度要求。

The work aims to optimize the crank arm of the top sealing mechanism of the roof box packaging machine. Firstly, the limit load of the original crank arm during working was solved by ADAMS. The quasi-static analysis of the initial crank arm was carried out by OptiStruct module in HyperWorks. The stress contour and displacement contour of the model were obtained. According to the analysis results, the structural optimization model based on relative density method was determined. Then, optiStruct was used to create the global response with the minimum volume as objective function, and the response related to the sub conditions with the maximum stress and the maximum displacement as the constraints, for the purpose of topology optimization. Finally, the optimized model and the connector were checked for the nonlinear finite element analysis by ABAQUS. The results showed that the weight of optimized model was reduced by 0.67 kg, the maximum stress value was 48.71 MPa, and the maximum displacement was 0.04 mm. The topology optimization design of the crank arm of the sealing mechanism is feasible. It can not only reduce the quality cost, but also meet the stiffness and strength requirements of the structure.