Generation of optimal parting direction based on undercut features in injection molded parts

An algorithm has been developed for the automated recognition of undercut f eatures for determining the optimal parting direction of injection molded p arts. On the basis of the 3-D solid model of a molded part described in Bou ndary Representation (B-Rep), the geometrical entities and the information of a solid model and their topological relationships are extracted. Accordi ng to these information, the criteria under which the undercut feature is f ormed are set up and the undercut feature directions (the withdrawal direct ions of side-cores or side-cavities) are identified. The optimal parting di rection is chosen based on the criterion of maximizing undercut feature vol umes in each undercut feature group. Through the case studies on industrial parts, the methodology developed is found to be efficient and effective in determining the undercut features and the optimal parting direction automa tically.