According to the analysis of the limitations of traditional method of tooth root bending stress calculation using in fatigue lifetime prediction

a method of calculating tooth root bending stress of involute spur gear under random loading is developed. The method consider the influence of dynamic loads

meshing point bending moment

pressure angle and load distribution along contact line. The results show that this calculation method can get high accuracy in teeth root bending stress calculate

and can get one tooth root bending stress change process in the gear transmission process. An effective method of calculating teeth root bending stress is provide for accurate gear bending stress spectrum and gear bending fatigue life prediction.