A Region Based Method to Automated Design of Multi-Piece Molds with Application to Rapid Tooling

Particularly for rapid tooling applications, delivering prototype parts with turn-aroun times of less than two weeks requires fast, proven mold design methods. We pre region-based approach to automated mold design that is suitable for simple twomolds (consisting of core and cavity), as well as molds with many additional mo sections. In our region-based approach, part faces are partitioned into regions, ea which can be formed by a single mold piece. The basic elements of our approac concave regions (generalized pockets) and convex faces since these elements are to the identification of regions. This paper focuses on the initial steps of automated design, including a problem formulation, methods for identifying the basic elements part faces, and combining them into regions. By seeking to minimize the number of pieces, different partitions of faces into regions are explored until the smallest numb regions is found. During this process, a linear programming problem is adopted finding a satisfactory parting direction of a region. Algorithms are presented for region generating and combining process. Our approach is illustrated with severa amples of industrial injection molded parts. @DOI: 10.1115/1.1505030 #

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