Research On Train Body And Assembling Connection Technology

Skeleton products include a large number of parts and have complex structure. Train body is one typical kind of skeleton products. If the train body is designed by traditional pattern, the design efficiency is low. This article proposes a component design method abased on reuse to achieve the rapid design of train body. A lot of assembly connection points need to design in the design process of train body, and existing design tools haven’t provided rapid design function of assembly connection points. According to this, research on fast layout algorithm and rapid design system of assembly connection points of skeleton products is proposed in this article.The article has mainly covered the following issues:(1) First, this paper defines the component concept of skeleton products and describes the attributes of the componen. Classification of the part feature is done based on the geometry. Then this paper discusses a simplified process of the additional features based on the CATIA history specification tree and analyzes the name semantic of part. The attribute matrix and assembly location matrix is established. Finally, a component classification method is proposed based on the part name semantic, the attribute matrix, assembly location matrix and additional features simplification. After the component classification of skeleton products, an extraction method of the component geometric properties is proposed. This paper describes the creation process of components powercopy template, and introduces the relationship between component instantiation and rapid design.(2) Based on the main structure of train body of type-25, the paper classifies the main parts of the train body with the component classification method, and then designs the train body components. The characteristics of top-down design method and the importance of its application on train body design are analyzed in this paper. The mathematical model of the train body skeleton is created based on top-down design method and the characteristic features of component. The article applies the mathematical model to extract the skeleton features of the train body. And then the skeleton features of the train body are designed with the CATIA knowledge engineering. Finally, the detailed design of the major parts of the train body is achieved the car-body component, achieving through style lines based on component reuse.(3) Several common constraints are defined based on the assembly environment of skeleton products. According to the assembly process requirements, the definition rules of the influence domain, margin distance, spacing distance and distance between two rows are proposed. The layout algorithm of assembly connection points is researched when no constrain exists or a single constrain exists under assembly condition. Based on the research above, a layout algorithm of assembly connection points is researched when several constrains exist under assembly condition. Finally, the article proposes a judgmental method to diagnose whether the assembly connection points are uniformed.(4) The rapid design system of assembly connection points is developed with the secondary development tool CAA. The system mainly includes the following five modules: assembly environmental identification, main part identification, curve offset, connection points generation and connection points editor. Assembly connection points of the train body are designed with the developed system. The feasibility and practical value of the system is verified.