Tool profile modification of hypoid gear machined by the duplex helical method

To avoid edge contact and stress concentration on the tooth surface of hypoid gear pairs machined by the duplex helical method for the drive axle of heavy-duty vehicles, a four-segment tool profile was designed for the simultaneous modification of the concave and convex surfaces of the pinion. First, a geometric model of the four-segment tool profile was established. Second, a mathematical model of the duplex helical method based on the four-segment tool profile was established, and a method for solving the tooth surface generated by the connecting points of the four-segment tool profile was presented. Finally, loaded tooth contact analysis based on finite element method was used to analyse the meshing performance of the gear pair obtained by the four-segment tool profile modification. The results of the original and modified gear pairs were compared. The tooth surface modification inhibited edge contact, improved the stress distribution, and decreased the maximum contact stress of the tooth surfaces, thereby improving the fatigue and wear life of the gear pair.