Tham khảo tài liệu 'the design of rolling bearing mountings (fag bearing co) episode 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Automotive differentials Design Spiral bevel-gear drives with or without intersecting axes are now almost always used for front and rear axle drives. Very high axial loads arise which with non-intersecting axes may be several times the tangential load at the pinion. Due to the limited space and the elevated torque values the pinion bearings are very heavily loaded. The pinion bearings should provide for even meshing of pinion and crown wheel under load therefore the pinion bearing arrangement should be as rigid as possible. The pinion is either an overhung or a straddled arrangement. The overhung arrangement is usually fitted with two tapered roller bearings adjusted against one another. Compact bearing arrangements double-row tapered roller bearings with an unsplit cup or a cup with a flange are common. The crown wheel is mounted in common with the differential. The meshing accuracy of the teeth should vary as little as possible and mounting should therefore be provided with sufficient rigidity. The rigidity requirements are easier to meet than with the pinion since more mounting space is available for this application and the axial loads are generally lower. Bearing adjustment Rigid pinion and crown wheel guidance is achieved by adjusting the bearings against each other with a preload. With grey-cast iron housings thermal expansion of the shaft increases the preload in nearly all cases after operating temperature is reached the preload must however never be such as to exceed the elastic limit of the bearing material. The opposite applies to aluminium housings which are being used more and more because of their lightness. So the preload has to be selected such as to achieve the required rigidity but the additional bearing loading must not significantly reduce the bearing life. This is the case if the axial preload does not exceed about half the external axial force Fa applied. Lubrication Differentials rely exclusively on oil lubrication. Bearings and gears are .
