IJAT Vol.17 No.6 pp. 619-626
doi: 10.20965/ijat.2023.p0619

Research Paper:

Automated Process Planning System for Machining Injection Molding Dies Using CAD Models of Product Shapes in STL Format

Isamu Nishida*,† ORCID Icon, Eiki Yamada**, and Hidenori Nakatsuji*

*Kobe University
1-1 Rokko-dai, Nada-ku, Kobe, Hyogo 657-8501, Japan

Corresponding author

**Trend Micro Incorporated
Tokyo, Japan

April 10, 2023
June 12, 2023
November 5, 2023
CAM, STL format, injection molding dies, end milling

In this study, we developed a method for automatically generating computer-aided design (CAD) models of injection molding dies. The method only required 3D CAD models of products in the Standard Triangulated Language (STL) format as the input information. We also developed a system for automatically generating numerical control (NC) programs by automating the system process planning necessary for machining the injection molding dies. The method generated CAD models of the injection molding dies by dividing the STL files of the products into triangular meshes on a specified split plane. For injection molding dies with several free curved surfaces, we acquired the tool positions of a ball end mill (as approximated by a spherical shape) and flat drill (as approximated by a cylindrical shape) from the geometrical relationships of the triangles constituting the CAD model. We generated a CAD model of an injection molding die using the proposed method with respect to the CAD model of a product shape to verify the validity of the developed system. Then, we machined the product based on the NC programs and tool position. In addition, we injection molded a product with a machined die to mold it into its original product shape.

Cite this article as:
I. Nishida, E. Yamada, and H. Nakatsuji, “Automated Process Planning System for Machining Injection Molding Dies Using CAD Models of Product Shapes in STL Format,” Int. J. Automation Technol., Vol.17 No.6, pp. 619-626, 2023.
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