注塑模CAD/CAE中曲面造型的关键技术

基于表面模型构造二维绘图、三维线框和自由曲面之间递升的层次关系。系统曲面生成的主要功能有构造管道型曲面，超限插值曲面、旋转曲面和直纹面等。构造Ｇ＾１连续的过渡曲面，实现曲面求交，裁剪和拼接等编辑功能，从线框模型上构造曲面模型。曲面造型系统输出的几何模型可以生成有限元网格，将网格数据传给ＣＡＥ分析程序就可用于注塑成形的流动，保压，冷却和翘曲分析。

Key Techniques of Surface Model for Injection Mold CAD/CAE System

A step-up hierarchical structure based on surface model was constructed. The hierarchy is from 2D drawing to 3D wire-frame and to free-form surface. The main functions of the generating surface in this paper are as follows: construct pipe-line surface, interpolating surface, revolving surface and straight-grain surface. In addition, G1 continuous blending surface was constructed. Surface editing function such as surface/surface intersection, surface trimming and surface conflating were realized. Surface model was constructed from wire-frame model. The plastic injection mold CAD/CAE system presented in this paper can output the information needed by CAE analysis. That is, the geometric model can generate finite element meshes automatically, and then the mesh data can be used to analyze the cavity filling, post-filling, cooling and warping of plastic parts.