Mathematical modelling and cutter design for generating chamfering of transversal profile for cylindrical gears

Gear chamfering is a significant machining process to improve the work performance of gear transmission like smoothness, low noise, and endurance. However, manufacturing uniform distributed transversal profile chamfer is still a challenge for traditional methods, particularly with considering the machining efficiency and economics. This work developed a generating machining-based chamfering method for cylindrical gears which can be integrated with the gear hobbing machining process. Firstly, the basic mathematic model of gear transversal profile chamfering including the geometry of cutter, gear chamfer, and installation are established with referring gear hobbing. Then, both the forward problem that identifies cutting edge by gear chamfer structure and the reverse problem that simulates transversal machined profile are studied. In this basis, the key interference-free cutter design is performed in three steps, i.e., modeling the cutting edge design as an optimal problem to obtain symmetric machined profile on gear end face, figuring out the lead of cutting edge by align the tooth flank to the swept surface of chamfer edge, and identifying interference or not through discrete section curves. At last, a numerical example is implemented and verified by VERICUT to prove the feasibility of this method.