Abstract: The design method of machine-tool settings is proposed on the spiral bevel gears with high contact ratio. Basing on the local synthesis method, TCA and LTCA techniques, a high contact ratio can obtained by enlarging the bias angle of contact path at the tooth surface. The method needn’t modify the geometrical parameters of the gears set and the gear machine-tool settings. The designed gears set may be cut by the present machine-tools and the standard serial cutter. The three designs of different contact paths are presented, the mesh simulation analysis are carried on and the contact ratio are tested. This results demonstrated that these method and theory can be design the spiral bevel of contact ratio reaching to 2.0~3.0.

Key words: Contact ratio, Machine-tools settings, Spiral bevel gears, TCA