What is cardan half shaft's structure?

The half shaft is also called the drive shaft, which is the shaft that connects the differential with the drive wheels. The semi-shaft is the shaft that transmits torque between the gearbox reducer and the drive wheels. Each of its inner and outer ends has a universal joint connected to the reducer gear and the inner ring of the hub bearing through the spline on the universal joint.

The structure of cardan wheel shaft

The half shaft is the shaft that transmits torque between the gearbox reducer and the drive wheels (previously, it was mostly solid, but it is easier to control the unbalanced rotation of the hollow shaft. Therefore, many cars use hollow shafts). The joints are respectively connected to the gear of the reducer and the inner ring of the hub bearing through the splines on the universal joints.

The half shaft is used to transmit power between the differential and the drive wheels. The semi-axes of ordinary non-disconnected drive axles can be divided into three types: full-floating, 3/4-floating and semi-floating according to the different types of external end support.

Classification of cardan axle shaft

The semi-axle commonly used in modern cars has two types of full-floating and semi-floating according to the different supporting types. (There are also three types, namely full-floating, 3/4-floating, and semi-floating)

Full floating half shaft

The semi-axle that only bears torque when working, and does not bear any force or bending moment at its two ends is called a full-floating semi-axle. The outer flange of the half shaft is fastened to the hub with bolts, and the hub is mounted on the half shaft sleeve through two bearings far apart. Structurally, the inner end of the full-floating half-shaft is made with splines, the outer end is made with flanges, and there are several holes on the flanges. Because of its reliable work, it is widely used in commercial vehicles.

3/4 floating half shaft

In addition to bearing the full torque, it also bears a part of the bending moment. The most prominent structural feature of the 3/4 floating half shaft is that there is only one bearing at the outer end of the half shaft, which supports the wheel hub. Due to the poor supporting rigidity of a bearing, in addition to the torque, this kind of semi-axle also bears the bending moment caused by the vertical force, driving force and lateral force between the wheel and the road surface. 3/4 floating half shafts are rarely used in automobiles.

Semi-floating half shaft

The semi-floating half shaft is directly supported on the bearing located in the inner hole of the outer end of the axle housing with a journal close to the outer end. The wheel disc and the brake hub are connected. Therefore, in addition to transmitting torque, it must also bear the bending moment caused by the vertical force, driving force and lateral force transmitted by the wheel. Semi-floating semi-axle is used in passenger cars and some vehicles of the same type due to its simple structure, low quality and low cost.