Automatic Side-Cores Construction in Injection Plastic Mold Design for Free-Form NURBS Surface Models

Abstract:

In computer-aided design for moldings, automatic generation of side-cores is a crucial design task that has an influence on the entire mold structure and manufacturing cost. This paper proposes a synthetic approach for creating the side-cores of free-form NURBS surface models. Based on the geometric properties of entities, surfaces of undercut features which are molded for side-cores are identified. After determining the withdrawal directions for each group of undercut’s surface features, the number of side-cores is optimized. The heads and the bodies of side-cores are finally obtained through the combination of the Boolean operation and 3D oriented extrusion. The algorithm is efficiently for both protruded and indented portions of undercut features. A complex industrial part is used to demonstrate the performance and robustness of the proposed algorithm. Since the approach is generic in nature, it is easy to be applied to any complex geometry in 3D mold design.

• Periodical: Applied Mechanics and Materials (Volumes 275-277)
• Pages: 2635-2639
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.275-277.2635
• Online since: January 2013
• Authors: Nguyen Huu Quang, Alan C. Lin
• Keywords: Mold Design, NURBS, Side-Core

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