Study on axial modification for uniform load distribution on tooth surface of helical gears in vehicle gearboxes

Abstract

Helical gears are widely utilized in vehicle gearboxes, where tooth breakage represents one of the key failure modes. The non-uniform load distribution on the tooth surface is recognized as a principal cause of this phenomenon. Axial modification is an effective approach to address this problem. Meshing contact analysis of gear pairs, including tooth contact analysis (TCA) and loaded tooth contact analysis (LTCA), facilitates realistic simulation of the gear meshing process. Integrating axial modification with TCA effectively resolves non-uniform load distribution on the tooth surface. However, challenges remain to be tackled: (1) Most TCA studies primarily focus on profile modification rather than axial modification, and (2) While LTCA offers insights into contact force distribution on the tooth surface, mathematical models for achieving uniform load are lacking. Furthermore, methods designed to attain uniform tooth surface load require refinement. Therefore, this article proposes a method to overcome these obstacles and introduces an axial modification approach to achieve uniform tooth surface loading. Two examples confirm the practicality of the proposed methods, and the results demonstrate significant improvement in alleviating non-uniform load distribution on the tooth surface.