Effects of Hob Tip Radius and Addendum Modification Coefficients on Tooth Bending Stress of Spur Gears under Dynamic Conditions

The paper presents a bending stress analysis of spur gear pairs in order to enhance the effects of the tooth root influence factors in relation to the hob tip geometry and addendum modification coefficients. These factors are evaluated in accordance with ISO 6336 for the basic rack profiles. In order to improve the accuracy of this analysis, a dynamic model is considered to analyse the shared dynamic load for a meshing cycle. All these influence factors are included in a global factor Y-d. A comparative study has been performed to investigate the effects of the hob tip radius, addendum modification coefficients and pinion speed on the variation of the factor Y-d on the meshing cycle. The approach makes for improved in predicting the tooth bending stress at the design stage.