Formation mechanism study on tooth surface of two gear finishing processes: combined theoretical and experimental approaches

As the necessary conditions, high precision and good mechanical performance gear is very important for a high speed and precision transmission system. To meet the requirement of the performance, gear finishing processes including gear honing and gear grinding have been mainly adopted. To compare the tooth surface of these two gear finishing processes, this paper gives the formation mechanism of gear tooth surface texture and conducts some comparative experiments on the gear surface texture and residual stress. Based on the spatial engagement principle and the discrete points of work-piece gear tooth spiral involute surface, the tooth surface contact area models of gears from the two processes are built, respectively, and the prediction models of honing paths and grinding paths are generated according to the velocity vector of the sampling points on tooth surface. Then the contrast and verification tests of the prediction models are carried out on internal gearing power honing machine and worm wheel gear grinding machine, respectively. Results indicate that the predicted curve shape honing paths and the longitudinal linear shape grinding paths of tooth surface are both similar to the experiment ones, respectively. Furthermore, some detailed quantitative analyses of tooth surface qualities including surface texture and tooth surface residual stress has been finished. It is found that the surface roughness value of gear grinding work-piece gear tooth surface is lower than that of gear honing process and the distribution of compressive residual stress on gear tooth surface is associated with the principles and parameters of the two processes. This research has theoretical and instructional significance for the improvement of gear honing and grinding processes.