Injection molding is widely used in industries to produce polymeric products. At present, compound NURBS surfaces are commonly used to represent freeform surfaces in mold models. This work uses T-spline surface with extraordinary control points instead of NURBS to represent freeform surfaces in mold models. Compared with NURBS, T-splines’ higher-order continuity facilitates the mold quality control especially at the patch boundary. And, its patch layout information can be utilized for tool path planning. We propose an algorithm to determine the patch processing order and generate nonretraction tool path for T-spline surface models. The tool paths are generated patch by patch using isoparametric strategy. Actual machining and injection molding experiments have been conducted. The result shows the feasibility of the proposed method, and the final product is in good quality.

中文翻译：

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用T-Spline曲面表示的注塑模具五轴刀具路径生成

注塑成型在工业中广泛用于生产聚合物产品。目前，复合 NURBS 曲面通常用于表示模具模型中的自由曲面。这项工作使用具有特殊控制点的 T 样条曲面代替 NURBS 来表示模具模型中的自由曲面。与 NURBS 相比，T 样条的高阶连续性有助于模具质量控制，尤其是在补丁边界处。并且，其补丁布局信息可用于刀具路径规划。我们提出了一种算法来确定补丁处理顺序并为 T 样条曲面模型生成非回退刀具路径。刀具路径是使用等参策略逐块生成的。已经进行了实际加工和注塑实验。结果表明了所提出方法的可行性，