Analysis and calculation of bending fatigue life of curve-face gear

Abstract

The curve-face gear pair is a new type of gear pair, and it has not been widely applied in many occasions as other kinds of gear pairs. In order to solve the bending fatigue life problem of this new gear pair with time-varying characteristics, a new theoretical calculation model was established. According to the loading state in actual operation, the single-tooth force model of curve-face gear pair was built, the effective loading of curve-face gear was analyzed, and loading spectrum in a period tooth was obtained. By building tooth equivalent cantilever beam model, the single-tooth bending stress calculation formula was derived, and the bending stress spectrums in tooth different sections were analyzed, meanwhile stress spectrum of bending fatigue hazard section in a period tooth was obtained. Combining the Miner’s rule and bending stress spectrum of dangerous section position, the bending fatigue life calculation method of curve-face gear was proposed. Through concrete example analysis, the bending fatigue life of curve-face gear was calculated. According to dynamic load spectrum extracted by ADAMS and bending stress calculated by ANSYS Workbench, the fatigue damage distribution of curve-face gear was obtained by nCode DesignLife. By constructing curve-face gear pair running experimental platform, the dynamic tooth root bending stress was measured. Comparing the theoretical calculation, simulation, and experimental results, the error between experiment and theory is within 10%, so the theoretical calculation method of bending fatigue life of curve-face gear was verified.