Study on Computer-Aided Process Planning of Mold Part Machining

Abstract

Large molds with very deep shape are used in producing plastic parts such as bumpers and inner panels of automobiles. In order to realize the precise and stable machining of the deep mold, 3-axis milling with inclined cutters is often applied in Japanese manufactures. Some machining regions are difficult to process with a cutter in a single orientation. Such regions must be subdivided into several smaller regions, so that each region can be processed with a single orientation cutter. The authors propose a new algorithm for automatically subdividing a machining region. A machining region is represented as a set of points covering the region. For each point, all accessible directions of a cutter are computed. Points are then classified into some groups based on the distribution pattern of accessible directions using our improved cluster analysis method. The classification result corresponds to the milling region subdivision.