Theoretical Research on Load Capacity of Double-Roller Enveloping End Face Engagement Worm Gear

Kai Wang1, 2, Jin Yao1, Jueling Wang*, 2, Jinge Wang3, Xingqiao Deng3
1 School of Manufacturing Science and Material, Sichuan University, Chengdu 610065, China
2 Department of Mechanical Engineering, Chengdu Industrial Vocational Technical College, Chengdu 610218, China
3 College of Mechanical Engineering and Automation, Xihua University, Chengdu 610039, China

© 2014 Wang et al

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


The calculation of load capacity is the key problem of worm's analysis. Taking the double-roller enveloping end face engagement worm gear as an example, a method for the numerical analysis of capacity was proposed based on finite element theory and fatigue analysis. Based on the meshing theory, the meshing equation was derived, and the accurate mathematical model for tooth surface of worm gear was established. Then the finite element modeling of worm gear was to analyze the contact stress and stress-strain effect. Finally, applying the safe life calculation method, the factors of fatigue life of worm gear were analyzed and researched. The researched result indicate that the worm gear has a quite good mesh performance when the worm meshing teeth have eight pairs. Under the same condition, with the analysis of the model's strength and finite elements performed, it was confirmed that the load capacity of end face engagement worm gear has an obvious improvement by comparison of that of enveloping hourglass worm gear, further, the maximum tooth root stress was only 6.5% of enveloping hourglass worm'. Meanwhile, the load distribution is in a declining invert L shape. And the fatigue life of end face engagement of worm gear pair could be attained 10 cycles. Therefore, this study results provided the theoretical basis and industrial applications value for transient analysis of end face engagement of worm gear and manufacturing constantly in the future.

Keywords: Double-roller, end face engagement, finite element analysis, fatigue analysis.