Balanced bending fatigue life for helical gear drives to enhance the power transmission capacity through novel rack cutters

This article proposes an idea for balancing the bending fatigue life between the gear and pinion of a novel helical gear drive. In this study, the helical gear is developed through analytical equations based on a novel rack cutter tooth thickness factor, and the estimation of principal stress and strain at the critical root fillet of the helical gear teeth is carried out through finite element analysis. Further, the fatigue module in COMSOL-Multiphysics software is employed to deter-mine the bending fatigue life through strain life approach based on Smith-Watson-Topper with Neuber's rule and fatigue usage factor based on Findley criteria. The effect of major gear pa-rameters such as helical angle, pressure angle, teeth number, gear ratio, addendum height and addendum modification factor (S+, S_ and S0) on bending fatigue life are computed based on novel helical gear with different rack cutter tooth thickness factor of gear and pinion. Finally, the above parametric study shows an optimum rack cutter tooth thickness factor between the gear and pinion to achieve a balanced bending fatigue life and fatigue usage factor, which aids in improving the power transmission capacity of the helical gear drive.