An automobile axle (also called a axle) is connected to a frame (or a load-bearing body) by a suspension, and wheels are installed at both ends. What it does: it is the suspension, not the axle, that transmits the force and torque between the frame and the axle (wheels). The function of the axle is to bear the load of the car and maintain the normal running of the car on the road.

Type:

The axle can be integral, like a huge barbell, with both ends supporting the body through the suspension system. The car bridge can also be split, like two umbrellas inserted on both sides of the car body, and then through the suspension system to support the car body, so the split car bridge and independent suspension.

According to the different driving mode, the axle can be divided into four types: steering axle, drive axle, drive axle and support axle. Among them, steering bridge and support bridge belong to driven bridge. Most cars use front rear drive (FR), so the front axle ACTS as the steering axle and the rear axle ACTS as the drive axle. The front axle is the steering drive axle and the rear axle is the support axle.

The structure of the steering bridge is basically the same, consisting of two knuckles and a beam. If you compare the beam to the body, the knuckle is his head swinging from side to side, the neck is what we call the kingpin, and the wheel is mounted on the knuckle as if it were a straw hat. Nevertheless, when driving straw hat turns, the head does not turn however, in the middle with bearing space, the head is right and left only shake. Neck -- the kingpin is the axis of rotation of the wheel. The axis of this axis is not perpendicular to the ground, and the wheel itself is not vertical.

The difference between a steering axle and a steering axle is that everything is hollow, the beams become the housing and the knuckles become the housing because there is an extra drive shaft. The drive shaft is split in two by a differential located in the middle of the bridge housing. The two straw hats are not simply attached to the head, but are directly connected to the two half-axes inside. The half axis also has a joint in the "neck" position -- the universal joint, so the half axis also becomes two parts, the inner half and the outer half.

According to the suspension structure type, the axle can be divided into two types: open type and integral type. The split axle is a movable joint structure, which is used together with the independent suspension. The central part of the integral axle is rigid solid or hollow beam. It is equipped with non-independent suspension. According to the different motion modes of wheels, the axle can be divided into four types: steering axle, driving axle, driving axle and supporting axle. Among them, steering bridge and supporting bridge belong to driven bridge. In general, the front axle is usually the steering axle, while the rear axle or the middle and rear axle are usually the drive axle. The front axle of cross-country car or most cars is both steering axle and drive axle, so it is called steering drive axle. Some single axle driven triaxles (6 x 2) have a drive axle (or rear axle) and a support axle (or middle axle).

To bridge:

1) the function of the steering knuckle swing to make the wheel deflection a certain Angle to achieve automotive steering; It bears the vertical load between the wheels and the frame, the longitudinal road resistance, the braking force and the lateral force, as well as the torque caused by these forces.

2) key indicators due to complex road conditions, the vehicle bridge needs to have a certain stiffness and strength. The steering wheel has the right positioning Angle and the right steering Angle. Minimize the quality of the steering wheel and the friction resistance of the transmission parts

3) composition: front axle, knuckle, kingpin and hub, etc. Front axle: its section is generally i-shaped, in order to improve the torsion strength, near both ends of a thickened part into a fist shape, which has a through hole, kingpin is inserted into the hole, the middle of the downward bending into a concave shape, its purpose is to make the engine position can be reduced, thereby reducing the car center of mass; Expand the driver's field of view; Reduce the Angle between the transmission shaft and the transmission output shaft. Knuckle: it is the hinge of the steering wheel, which is a forked piece. The upper and lower forks have two coaxial holes for the kingpin and the knuckle journal for the wheels. The two ears of the pin hole on the knuckle are connected with the knuckle shaped part at both ends of the front axle through the kingpin, so that the front wheel can deflect the kingpin to a certain Angle to make the car turn. Kingpin: hinge the front axle and knuckle so that the knuckle swings around the kingpin to turn the wheel. The middle part of the kingpin is cut with grooves. When installing the kingpin, fix the bolt with the grooves above it and fix the kingpin in the fist hole of the front axle. The kingpin is dynamically matched with the pin hole on the knuckle to realize the steering hub: the wheel hub is supported on the journal outside the knuckle by two conical roller bearings. The tightness of the bearing can be adjusted by adjusting nut (mounted on the outer end of the bearing).

Drive axle.

1. The role of the drive axle is to transfer the driving force from the engine to the driving wheels, so as to achieve the effect of reducing speed and increasing torque, and at the same time change the direction of power transmission.

2, the composition of the drive axle is composed of the main reducer, differential, half shaft, bridge housing.

FF: clutch, transmission, main reducer, differential, drive axle components are installed in the transmission housing, located in the front of the car, power transmission to the front wheels. FR: main reducer, differential and drive axle components are installed in the drive axle housing, located at the rear of the car, and the power is transferred to the rear wheels.

Steering axle:

1. Function: it has two functions of steering and driving. It has not only the basic parts of the general drive axle, but also the steering axle special kingpin.

2. The structural composition of the steering drive axle has the main drive reducer, differential and half axle of the general drive axle; Also has the steering knuckle shell, the kingpin and the wheel hub which the general steering bridge has. Compared with the separate drive axle and steering axle, it is different in that the required half axle for steering is divided into two parts, called the inner half axle (connected with the differential) and the outer half axle (connected with the wheel hub), which are connected with the universal joint of equal angular velocity. At the same time, the main bridge is also divided into two sections, respectively fixed on the spherical bearing of the universal joint. The knuckle journal is hollow so that the outer half of the shaft passes through it. The connecting fork of the knuckle is a spherical knuckle housing, which not only meets the need of steering but also ADAPTS to the transmission force of the knuckle. Steering axle is widely used in all - wheel drive cross - country vehicles

3. Working process of steering drive axle: the central part of the axle is equipped with the main reducer and differential. The inner half shaft and the outer half shaft are connected together through the universal joint of equal angular velocity. When the current bridge is driven, the torque is transferred from the main reducer and differential to the inner axle, universal joint, outer axle and axle flange, and finally to the hub, driving the wheels to rotate. Steering: the knuckle is bolted together by the knuckle journal and knuckle housing. The knuckle journal is provided with two hub bearings to support the hub; The inner bore wall of the knuckle shaft is internally pressure bushing to support the outer half shaft. The upper and lower ends of the knuckle housing are respectively provided with the bold parts of the upper and lower kingpins, and the stop pin is used to stop the movement. The upper end of the knuckle housing is provided with the knuckle arm, and the lower end of the knuckle housing is provided with the lower cover. After the grease is injected by the upper and lower nozzles, it enters into the oil channel of the kingpin center respectively, and then enters between the kingpin and the bushing from the two side holes to realize lubrication. When the automobile turns, the steering straight tie rod pulls the steering knuckle arm to drive the steering knuckle to swing around the kingpin, then the steering wheel can deflect accordingly, thus realizing the automobile's turning.

Support the bridge:

The supporting bridge belongs to the driven bridge. The rear axle is designed to support the axle trailer, and the rear axle of the front drive car is also a supporting axle.