(3) Selection of Supporting Mode an

(3) Selection of Supporting Mode and Installation Mode of Driven Bevel Gear Tapered roller bearings are used for both ends of driven bevel gears. When installing, their tapered rollers should have their big ends facing inward and their small ends facing outward. In order to prevent the driven bevel gear from shifting under axial load, the tapered roller bearing should be adjusted by adjusting nuts at both ends. The driven bevel gear of the main reducer adopts a radial structure and is fixed on the flange of the differential case with fine-tooth screws with high precision [6].(4) Pre-tightening of the bearings of the final reducer and gear meshing adjustment The tapered roller bearings supporting the final reducer need to be pre-tightened to eliminate the original clearance during installation, increase the clearance during running-in and enhance the supporting rigidity. The analysis shows that when the axial force is linearly related to the spring deformation, the axial displacement is reduced to 1/2 of the original one by pre-tightening. Although pre-tightening force can increase the bearing stiffness and improve the gear meshing and bearing working conditions, when the pre-tightening force exceeds a certain ideal value, the bearing life will drop sharply. The pre-tightening value of the main reducer bearing can be taken as 30% of the axial force converted from the maximum torque of the engine.The pre-tightening degree of driving bevel gear bearing is adjusted by sleeve and gasket, and the pre-tightening degree of driven bevel gear bearing is adjusted by adjusting nut.(5) Deceleration form of main reducer The deceleration form of main reducer is divided into single-stage deceleration, double-stage deceleration (as shown in Figure 1.4), single-stage penetration, double-stage penetration, main deceleration and wheel deceleration, etc. The choice of deceleration form is related to the type and service conditions of the automobile, and sometimes to the product series and manufacturing conditions of the manufacturer, but it mainly depends on the size of the main reduction ratio io, the ground clearance under the driving axle, the number and arrangement of driving axles, etc. Generally, single-pole reducer is used in various small and medium-sized cars with main reduction ratio io≤7.6.