Gear Hobbing Cutting Process Simulation and Tool Wear Prediction Models

Abstract

Gear hobbing is an efficient method to manufacture high quality and performance toothed wheels, although it is associated with complicated process kinematics, chip formation and tool wear mechanisms. The variant cutting contribution of each hob tooth to the gear gaps formation might lead to an uneven wear distribution on the successive cutting teeth and to an overall poor tool utilization. To study quantitatively the tool wear progress in gear hobbing, experimental-analytical methods have been established. Gear hobbing experiments and sophisticated numerical models are used to simulate the cutting process and to correlate the undeformed chip geometry and other process parameters to the expected tool wear. Herewith the wear development on the individual hob teeth can be predicted and the cutting process optimized, among others, through appropriate tool tangential shifts, in order to obtain a uniform wear distribution on the hob teeth. To determine the constants of the equations used in the tool wear calculations, fly hobbing experiments were conducted. Hereby, it was necessary to modify the fly hobbing kinematics, applying instead of a continuous tangential feed, a continuous axial one. The experimental data with uncoated and coated high speed steel (HSS) tools were evaluated, and correlated to analytical ones, elaborated with the aid of the numerical simulation of gear hobbing. By means of the procedures described in this paper, tool wear prediction as well as the optimization of various magnitudes, as the hob tangential shift parameters can be carried out.

Prognosis of the local tool wear in gear finish hobbing

“…To analyze the chip geometries and the local load on the cutting edge in geometrically complex gear cutting processes, geometrical simulations are used [1][2][3][4][5]. The software SPARTA developed by Winter [2] is based on penetration calculation and enables to determine undeformed chip geometries in gear hobbing.…”

A comparative analysis of the geometrical surface texture of a real and virtual model of a tooth flank of a cylindrical gear

“…3b). Taking the simulation parameters corresponding to the real generation parameters, it is possible to obtain a solid gear wheel model without the errors resulting from the real generation process [19,21,27,28]. To obtain the models of the surfaces of the gear teeth of the constructional parameters, the following methodics of calculating the parameters of a computer simulation of gear generation was adopted: …”

Spur gears with longitudinal tooth profile modification mesh creating which is suitable for stress analysis

“…This fact was the reason why authors devoted their work for developing a special meshing computer program improving the efficiency during preparation of discrete models of spur gears with special geometry features being the result of tooth profile modification. Improvement of exploitation features such as lower noise and longer durability should be the results of complex manufacturing method based on numerical computations and experiments [9][10][11][12][13][14][15][16].…”