A topological flank modification method based on contact trace evaluated genetic algorithm in continuous generating grinding

A method for topological modification of gear flanks in continuous generating grinding based on contact trace evaluated genetic algorithm (CTEGA) has been proposed to solve the problem of flank twist caused by lead modifications of gear flanks. Firstly, according to the theory of conjugate surface, a mathematical model calculating the generating surfaces of worm wheel as well as representing the wheel as two-parametric form spiral surface has been established. Secondly, by representing the radial, axial, and tangential feed of worm wheel in forms of polynomials of the axial feed of worm wheel, a mathematical model of generating gear grinding process has been established where the axis linkage relationship in CNC machine is intentionally changed for topological modification of target tooth surface. Finally, the validity of the proposed topological modification method was numerically demonstrated using a helical gear made by the CNC continuous generating grinding machine. The method proposed in this paper can realize the topological modification of gear flanks by only adjusting motions of numerically controlled axes in the grinding process without adopting a specific dressing of the grinding wheel.