Optimization of Tooth Root Profile of Spur Gears for Maximum Load-Carrying Capacity

Increasing the strength of the gear tooth is a recurrent demand from industry. The authors report a novel approach to the design of tooth-root profile of spur gears using cubic splines, with the aim of investigating the effect of tooth-root geometry on stress concentration in order to increase the gear tooth strength by optimizing the root profile. An iterative co-simulation procedure, consisting of tooth-root profile shape synthesis via nonlinear programming and finite element analysis software tools is conducted, for the purpose of forming the tooth-root geometry design with the minimum stress concentration. The proposed design was verified to be capable of reducing the stress concentration by 21% over its conventional circular-filleted counterpart. Hence, the results showcase an innovative and sound methodology for the design of the tooth-root profile to increase gear load-carrying capacity.