Contact and Transient Elastohydrodynamic Lubrication Analyses of Involute Spur Gears with Asymmetric Teeth

J. J. Liou

《Proceedings of the 14th IFToMM World Congress》 14th-3 (2015/10) Pp. 567-576

https://doi.org/10.6567/IFToMM.14TH.WC.OS18.006

並列摘要

In this paper, a transient non-Newtonian elastohydrodynamic lubrication (EHL) analysis is applied to investigate the influence of tooth asymmetry on the transient lubricated characteristics of involute spur gears. The time-varying gear mesh parameters including the normal tooth force, radii of curvature, rolling, and sliding are calculated from the gear load distribution, kinematics, and the geometry of asymmetric tooth profile. A new set of formulae, which can accurately predict the high-pressure rheology of quantitative elastohydrodynamics, is incorporated in the present EHL analysis to simulate the lubricated gear contacts. Numerical predictions show that tooth asymmetry can significantly affect the distributions of pressure, film thickness, and coefficient of friction during the gear meshing. Asymmetric gears with higher pressure angle on the drive sides can have lower pressure, thicker film thickness, and lower coefficient of friction. The effects of tooth asymmetry on the power losses due to tooth friction in gears and noise level are also discussed in this paper.

並列關鍵字

Transient EHL ； Spur gear ； Asymmetric teeth ； Free volume ； Shear-thinning