Abstract: FEM is an important method to predict the tooth root bending stress of driving axle hypoid gear of automobile. However, it is difficult to accurately determine the constraint condition of the FEM model. To solve this problem, a finite element analysis method of hypoid gear tooth root bending stress based on the whole drive axle model is established. Simulation results of obtained from the proposed method are compared with that of rig test. ABAQUS/Standard software is used to establish the static state engagement model of hypoid gears of the driving axle. Results show that, while hypoid gears of the driving axle are meshing, the maximum bending stress of the pinion appears near the heal; the tooth roots bear the comprehensive stress first, then shift to tensile stress. On the contrary, the maximum bending stress of the big gear appears near the toe; the tooth roots bear the tensile stress first, then shift to comprehensive stress. Finally, the gear tooth root bending stress was measured on a driving axle static torsional test rig. Comparison of the test and simulation results demonstrates that the proposed FEM model is reliable and such modeling method can be applied to similar analysis of gear tooth root bending stress.

Key words: vehicle engineering, drive axle, hypoid gear, root bending stress, finite element method