Research On Part-Library Design Based On Assembly And 3D Dimension

In the face of the aggravated challenge on products competition and in order to strengthen the competitiveness of the products, enterprises generally pay attention to improving the design level of the products. The conceptual design of the concept is the key stage in the product design, it determine the capability and cost of the final products to a great extent. Traditional model method is only brief pile of geometric graph and only describe the visual form of the products, but it isn't include design ideas of products, namely topological relation and relation of restraining between geometric graph elements; and traditional model methods also haven't dimension drive function that can change the graphs of products when the size of products is changed. Thus, even change a size of the complicated model, it is need to wipe all of the original figure, and construct a new figure again; So such simple repeated work influences design efficiency seriously. The new three-dimensional model system has offered the function of parametric design, which makes the geometry measurement of the figure and size data set up relationship; it can realize the change of the geometry model through altering the data.The purpose of this subject is regard to developing the three-dimensional entity's shape-designing software that used for conceptual design of engineering products with perfect function. On the basis of three-dimensional CAD software JhSolid systematic frame, it is designed with object-oriented method, synthetically uses computer science, computer aided geometric theory, graphical theory, key functions that Parasolid offered. Main functions are following: by setting up part-library for part assembly with the variable design method, it is realize that drive parts which in assembly environment with change dimension value in variable form; it sets up common transmission-part-library for assembly with parametric design method of CAD, and designs parametric axis, and based on face code method it drive common transmission-parts after which have been assembled; it realizes transform of dimension from 2D to 3D, and directly mark dimensions of parts in 3D environment.Worked out by the procedure, debugging and test repeatedly, it has verified that these programs have succeeded in realizing above-mentioned functions, which prove the correctness and feasibility of this method.