A Novel Asymmetric Tooth Flank Modification Modeling Method for the Cylindrical Helical Gears

To enable effective regulation of the contact pattern location on tooth flanks and eliminate edge contact in cylindrical helical gear pairs, a novel asymmetric modification method that simultaneously addresses both the tooth profile and the tooth lead direction is proposed. Firstly, a mathematical model of the theoretical tooth flank of cylindrical helical gears is derived. Then, the superposed modification amounts are formulated on the tooth surface by dividing into subregions along the profile and width directions, and the mathematical model of asymmetrically modified cylindrical helical gear tooth flanks is established by integrating the theoretical tooth surface and the superposed modification amounts. Finally, the finite element analysis meshing models with unmodified, symmetrical, and asymmetric modified tooth flanks are established to verify the feasibility of this method through comparative contact pattern location. The result shows that tooth surface asymmetric modification retains the ability to eliminate edge contact and an additional capability of regulating the contact pattern location is achieved, which is more adaptable to diverse application scenarios in gear transmission systems.