To ensure the quality of structure design and efficient configuration of mechanical products, a part family architecture model based on hierarchy tree constraints was proposed. In this model, the part family properties domain and assembly structure domain in product were expressed in parametric methods.The members of part family depend on the values of part family characteristic parameters.Finally,the model was illustrated with the example of a bridge crane part family modeling. 

part family, tree constraint, architecture model, characteristic parameter

为保证复杂机械产品具有良好的设计结构和高效的配置求解，提出了一种基于树状约束的零部件族结构模型。该模型以参数化的方法描述了产品结构中零部件族的特征属性域及装配结构域，并表达了零部件族成员及零部件族自身特征参数间的依赖约束关系。最后，以桥式起重机零部件族的约束建模为例，验证该零部件族结构模型的适用性。

零部件族, 树状约束, 结构模型, 特征参数