Combined Effects of Lead Crowning and Assembly Deviations on Meshing Characteristics of Helical Gears

This paper describes a FEM based approach aimed to investigate the effects of lead and profile modifications in combination with machining and assembly deviations on meshing characteristics of helical gears. The proposed approach allows introducing any three dimensional tooth flank modifications (i.e. profile, longitudinal or more complex modifications) along with manufacturing and assembly deviations. In the paper, a sample gear set will be used to investigate the combined effects of lead crowning and assembly deviations on tooth root stresses, contact pattern, load-sharing ratio and transmission error. The approach has been validated with experimental data and its application is illustrated through sample case studies. On the basis of the obtained results, some general conclusions on the effects of lead crowning and assembly deviations in helical gears useful for gear designers are finally drawn.