A study of interferential tool position correcting algorithms in 3D impeller variable-axis rough plunge milling

Abstract

Plunge milling has significantly improved the rough machining efficiency of 3D impeller channels. However, in conventional plunge milling cutter position planning, interferences occurring at the end of every cutter position due to the sudden increase of radial depth is inevitable. This can seriously compromise the service life of the machine tool and cutter, and also reduce the efficiency at the interferential phase. This study optimised the tool path cutter axis vector of conventional rough machining of 3D impeller variable-axis plunge milling, thus making the angle between the normal vector of workpiece surfaces at the cutter contact point, and the cutter-axis vector of the adjacent tool position, gradually increase from the outlet to inlet on a very small scale. Based on this, an iterative algorithm for the tool centre position and cutter safety height was obtained, thus making the hub allowance of the optimised tool path for plunge milling as small as possible without affecting subsequent machining by avoiding the interferential phenomenon. Finally, the proposed method was verified by relevant numerical examples.