Introduction: auto-hub bearing riveting process

The role of auto-hub bearing is mainly support the weight of the car and provide feeling really guide wheel transmission. Wheel hub bearing is bear radial load and axial load under, is a very important safety. Now domestic cars are mostly still adopts the traditional two separate set of tapered roller bearing and angular contact ball bearing, this structure should be adjusted when car assembly clearance, preloaded, fatliquoring process, mixed more artificial control factor, assembly is difficult, resulting in the automobile assembly line extension, high cost and poor reliability, it is difficult to adapt to the fierce market competition. In recent years, with the rapid development of front front drive cars, wheel hub bearing, great changes have taken place, especially foreign well-known car manufacturers with bearing manufacturers joint research and development, the new wheel hub bearing unit, the blend of the fourth generation. The third generation wheel hub uranium bearing NSK riveting pressure forming in the traditional design of the third generation wheel hub bearing units, two inner ring is connected with lock nut securely, NSK development and the new structure is through the shaft of the riveting pressure forming axial force make the belt flange of the inner ring produces plastic deformation, and small inner circle pressure. Remove the nut helps to reduce the weight and size of wheel hub unit, improve the reliability. The driving wheel and the drive wheels are applicable. The riveting pressure forming technology, reliability will be improved, even loose coupling nut bearing itself can provide a preloading guarantee. USES a riveting riveting pressure forming process ( As shown in figure) , tilt the rivet head ( Upper die) Riveting pressure on bearing components, with the shaft end of the flange inner ring produced by the pressure from the lower plastic deformation, firmly together until the small inner circle. In the process of forming, wheel deformation is divided into three stages: the first stage, the rivet head drop, contact with the wheel shaft, deformation. Deformation of the second stage, further expand, wheel axis along the radial expansion, contact with inner ring chamfer. The last is the third stage, the riveting process is complete. In the first stage, almost all of the rivet head pressure is used for wheel shaft, initially forming inner ring load is small and constant. Into the second stage, the rivet head pressure to the inner ring, inner ring load increases quickly. In the third stage, because the rivet head pressure inner ring load increased gradually until saturated, after the riveting pressure, or even a riveting has been raised, inner ring load has not been eliminated, still retain some of the load. Can be thought of residual load form the clamping force. The traditional die forging the whole compression artifacts, produce plastic deformation. Therefore, when the large size workpieces, need a lot of pressure, and when used in bearing, deformation often exceeds the central area. In such a huge pressure, the ball and raceway are squeezed, in processing bearing is likely to be damaged, and riveting process only in local deformation and only a small pressure. By controlling the load pressure, this kind of processing used in bearing assembly is very suitable. Riveting are verified by overloading the operation durability test pressure forming of fatigue strength and creep resistance of the inner ring. Static strength experiment was carried out to examine riveting pressure forming of static strength and bearing load moment just test, because of the bearing rigidity can affect the manipulation stability of the vehicle cornering. NSK newly developed according to the result of the experiment, the rivet forming inner ring self-locking of the third generation wheel hub bearing is equal to or even better than that of traditional wheel hub bearing lock nut. On the premise of guarantee high reliability, the weight and size is reduced, to satisfy the current market demand, reduce the vehicle fuel consumption.