Spur face gear generation milling on a non-orthogonal five-axis CNC machine and influence of setting errors

In certain automobile and other transmissions, spur face gear drives replace bevel gear pairs. Since CNC machine with complex multi-axes motions is required for its manufacture, an innovative CAD simulation is carried out first using Boolean operations in an incremental manner. The proposed approach is validated by comparison with analytical surface derived from the first principle. As a frugal measure, an available five axis CNC machine, having a cutter on non-orthogonal B-axis and gear blank on C-axis is selected. The CAD approach is also extended to simulate generation milling on the selected machine using its kinematics and employing simultaneous five-axis motions. The generated surface is compared with the analytical surface and deviations are reported. Also, analysis of setting errors reveals that Y-axis offset and B-axis setting error have a greater influence on the surface geometry. The results of CAD simulation have been verified by machining a spur face gear on the selected CNC machine and measuring it on a CMM. Further analysis of the results could lead to appropriate corrections in the settings to improve the face gear accuracy.