A Novel Simulation Approach to Determine Thermally Induced Geometric Deviations in Dry Gear Hobbing

Abstract The ability to predict temperature distributions in workpiecesduring dry gear hobbing, especially of large ring gears, enables the avoidance of lubricants. Up to now wet hobbing is state of the art in the gearing industry. The calculation and compensation of thermal deviations during dry gear hobbing is necessary to achieve high gear quality. Based on previous work, which was concentrated on chip forming, the current simulations are performed for the full hobbing process of a complete gear with the focus on thermal distributions and the following geometry deviations. A modified dexel model is presented in the paper which is able to describe modern gear geometries, to store temperature fields and to provide information for 3D visualizations at every time. Additionally a numerical simulation of the complex gear hobbing kinematic is effectively realized with the help of quaternions algebra and parallel computations. The problem of thermo-mechanical coupling is solved by using commercial FE software and a self-developed finite difference based solver. Subsequently different compensation strategies will be discussed against each other by the help of the developed simulation model to avoid thermal deviation in advance.