Abstract: Aiming at the frictional heating problem of tapered roller bearings, the contact form, force and contact ellipse of tapered roller ball base surface and conical rib were studied. The calculation method and shortcomings of the rib angle in the current design method of tapered roller bearings were summarized. Based on Hertz point contact theory, a contact calculation model between ball base surface of tapered roller and conical rib was proposed. Taking a single row tapered roller bearing for an automobile as an example, and given the bearing parameters and operating conditions, the force on the roller surface was solved according to the force balance of the bearing. For the roller with the greatest force, the influence of the change of the inclination angle of the rib edge on the stress and the parameters of the contact ellipse was discussed by iteration method under the condition that the contact ellipse edge was exactly at the limit position of the oil ditch edge. The results indicate that with the increase of the rib angle, the parameters of the contact ellipse decrease and the friction decreases. After considering the factors of roller skew and misalignment, the rib angle value is optimized, which can improve the friction problem of the rib edge.
Key words: tapered roller bearing; sphere surface; rib angle; hertz contact; contact ellipse