Effective Tool Pass Generation Method for Roughing in Multi-axis Control Machining

Abstract

In recent years, 3-axis control machining is generally performed in roughing process. However, 3-axis control machining is not efficient in case of roughing complicated shapes, i. e., parts with overhanging shape, because it requires to reset the workpiece. To solve this problem, 5-axis control machining has been developed. However, there has been no roughing procedure in 5-axis control machining. The study deals with roughing by 3+2-axis control machining, which performes 3 translational axis machining after determining a suitable tool axis vector by 2 rotational axis movement. For 3+2-axis control machining, the determination of tool axis vectors and tool diameters largely affects the rough machining time. The study proposes a method of determining the optimal tool axis vectors and selecting the tool diameters for efficient roughing. At first, the method searches candidate of tool axis vectors after calculating machinable area in each tool axis vector, applying the multi-stage decision process. Then, the method determines the combination of tool axis vectors and tool diameters, using a peformance index. The effectiveness of the proposed method was demonstrated by the machining experiment of an impeller.