Gear Optimization

In this study, an optimization methodology is presented to systematically define head-cutter geometry and machine tool settings to introduce optimal tooth modifications in spiral bevel and hypoid gears. The goal of the optimization is to simultaneously minimize the tooth contact pressure and the angular displacement error of the driven gear (the transmission error), to maximize the elastohydrodynamic (EHD) load carrying capacity of the oil film and to minimize the power losses in the oil film. The proposed optimization procedure relies heavily on the loaded tooth contact analysis for the prediction of tooth contact pressure distribution and transmission errors and on the EHD lubrication analysis developed by the author of this paper. The core algorithm of the proposed nonlinear programming procedure is based on a direct search method. Effectiveness of this optimization was demonstrated on spiral bevel and hypoid gear examples. Considerable reductions in the maximum tooth contact pressure and in the transmission errors and drastic increase in the EHD load carrying capacity of the oil film and reduction in the power losses in the oil film were obtained.