Structure
The driving system is divided into four main parts: axle, wheels, frame, and suspension.
Function
The axle is connected to the frame (or load-bearing body) through suspension, and car wheels are installed at both ends. Its function is to transmit the forces in all directions between the frame (or load-bearing body) and the wheels.
Type
The axle can be integral, like a huge barbell, with both ends supported by a suspension system to support the body of the vehicle. Therefore, integral axles are usually paired with non independent suspensions; The axle can also be detachable, like two umbrellas inserted on both sides of the vehicle, and each supported by the suspension system, so the detachable axle is used in combination with independent suspension.
According to the different driving modes, the axle is also divided into four types: steering axle, drive axle, steering drive axle, and support axle. Both the steering axle and the support axle belong to the driven axle. Most cars use front rear drive (FR), so the front axle serves as the steering axle and the rear axle serves as the driving axle; For front wheel drive (FF) cars, the front axle becomes the steering drive axle, while the rear axle serves as the supporting axle.
The structure of the steering axle is basically the same, consisting of two steering knuckles and a crossbeam. If we compare the crossbeam to the body, the steering knuckle is his swaying head, the neck is what we often refer to as the main pin, and the wheels are mounted on the steering knuckle, as if wearing a straw hat on his head. However, when driving, the straw hat rotates but the head does not, separated by a bearing in the middle, and the head only sways left and right. Neck - The main pin is the axis of rotation of the wheel, and the axis of this axis is not perpendicular to the ground, nor is the wheel itself vertical. We will discuss this in detail in the wheel alignment section.
The difference between a steering drive axle and a steering axle is that everything is hollow, the crossbeam becomes the axle housing, and the steering knuckle becomes the steering knuckle housing because there is an additional drive shaft inside. This drive shaft has been divided into two half shafts by the differential located in the middle of the axle housing. Two straw hats are not simply placed on the head, they also need to be directly connected to the two half shafts inside. The half shaft also has an additional joint at the neck position - a universal joint, so the half shaft has become two parts, the inner half shaft and the outer half shaft.