These are all wheel hub bearings.
The wheel hub bearing is a part that connects the tire (rotating part)/brake disc (rotating part) and the steering knuckle (fixed part). Its main function is to reduce friction for the rotating pair, and at the same time it also plays a role in transmitting force. It bears very large radial load (vehicle weight) and axial load (lateral force or lateral impact force of the tire when turning).
The structure of the first generation of bearings is the simplest, mainly consisting of an inner ring, an outer ring and steel balls. And the lowest cost.
The structure of the second-generation bearing is slightly more complicated, and the wheel hub is integrated on the basis of the first-generation bearing.
The inner ring of the third-generation bearing is integrated with a hub (Hub), and the outer ring is integrated with a flange connecting the steering knuckle, which can be connected with the steering knuckle by bolts. The assembly accuracy is greatly improved.
And because all dimensions are precisely controlled by the supplier, the performance is the best.
Due to these two advantages, although the cost is slightly higher, the third-generation bearings are still favored by almost all mainstream car manufacturers.
