Based on ease-off theory, a high-order contact analysis method for spiral bevel gear tooth surface is proposed. Compared with previous methods, it has made great progress in calculating high-order contact parameters of spiral bevel gears. The summary is as follows:
1) The analytic relationship between the combination of ease-off topological surface equation and the higher-order contact parameters of discrete tooth surfaces is established;
2) Based on ease-off and discrete tooth surfaces, the proposed high-order contact analysis method combined with the finite difference algorithm effectively avoids the complicated high-order contact theory which is not easy to realize;
3) Numerical examples show that the short-range curvature fluctuation values of the contact line with three groups of parameters are 0.0000769, 0.000586 and 0.000127 respectively. It shows the complexity of actual tooth surface contact. Furthermore, the feasibility and effectiveness of the high-order contact analysis method of discrete tooth surface are verified. at the same time, the high-order contact analysis can reflect the tooth surface contact state more intuitively and comprehensively, which provides a reference for the subsequent high-order contact tooth surface design.