关键词: 数学模型, 自由度, 装配公差, 装配定位接点, 配合类型

Abstract: Aiming at the problem that the present assembly tolerance model could not represent information of assembly positioning joints completely,the relationship between parts positioning feature and assembly positioning joints was investigated.To correct conventional assembly tolerance math model,the fit modes of assembly positioning joints were classified,and the constraints of different fits on parts'degree of freedom were represented with victor equation and inequality.The tolerance information of auxiliary joints could be expressed with obtained victor equation and inequality,which could be used to improve conventional mathematical model of assembly tolerance.An example was given to illustrate the application of the proposed model in tolerance analysis.

Key words: mathematical model, degreed of freedom, assembly tolerance, assembly joints, fit mode