Axle for guiding and driving

As one of the three major components of truck power, axles, in addition to working closely with the engine and transmission to drive the vehicle, but also have to bear the weight of the truck to maintain the stability of the vehicle under changing conditions, today we will talk about the knowledge of the axle.

▎What are the forms of axles?

The function of the axle is like "insect feet", so some vehicles with many axles are called millipedes. Its function is to connect with the suspension, and then install wheels at both ends of the axle. From the appearance, it can be understood that it can drive, bear, and guide the truck, and the axles are also divided into four forms, namely: drive axle, steering axle, floating axle, and steering drive axle.

Everyday road transport vehicles use the front axle as the steering axle and the rear axle as the drive axle, as common in the market: 4X2, 6X2, 6X4 and other models are formed by changing the combination of axles, but like some vehicles with off-road needs Trucks will be equipped with all-wheel drive. The front axle can not only be steered, but also used as a drive axle. This is the steering drive axle mentioned above, commonly known as: four-wheel drive, all-wheel drive models.

The common forms of floating axles are: 6X2, 8X2 models, generally this axle is installed in the front of the drive axle, some models have steering and lifting functions, and some models only have the lifting function, there is no driving function, just play a role in improving the bearing capacity.

▎The structure of the axle

Like some common steering axles and drive axles, I believe everyone is familiar with them, while the steering drive axle is a relatively unfamiliar thing. Because ordinary road transport vehicles do not have it, it will only be involved in some mountain transportation fields. Here we still need to have a deeper understanding of the composition of the axles.

(1) Steering axle

Let’s start with the common steering axle. As the name suggests, it is an axle that provides steering for the vehicle. It is mainly composed of: bridge, king pin, steering knuckle, wheel hub, and brake. The bridge shape of the steering axle is the most common I-shaped. Its advantages are higher load-bearing and flexibility.

In general light trucks and micro trucks, you can also see a straight-line bridge. The steering part is directly connected by the king pin and the steering tie rod, and is installed at both ends of the bridge. The brake and the hub are installed on the steering knuckle. , When the driver turns the steering wheel, with the help of the steering gear, the trapezoidal structure connects the steering knuckle on one side, and drives the wheel on the other side to rotate through the tie rod to complete the entire steering process.

(2) Drive axle

The composition of the drive axle will be relatively complicated, after all, it not only bears the load but also plays the role of driving. The power transmission with the gearbox is completed through a drive shaft, the power output from the engine is decelerated and torque is increased, and after changing the transmission direction, the main reducer and the half shaft are output to the wheels, forming the so-called on-wheel power.

The drive axle is mainly composed of: axle housing, main reducer, differential, half shaft, hub, and braking mechanism. The axle housing is also divided into many types, which are generally distinguished by the tonnage of different axles, and there are also half shafts. The difference between the axle and the wheel-reduction axle is due to its special function. Generally, the steering axle is equipped with a single wheel, while the drive axle is composed of two wheels on one side, which improves the grip and bearing capacity of the vehicle.

(3) Steering drive axle

This steering drive axle combines the functions of the steering axle and the drive axle. It is an axle that has both steering and driving functions. It is composed of steering knuckles and other components. The biggest difference between it and ordinary axles is that two universal joints are added to the half shaft part to solve the problem of conflict between driving and steering.

▎Axle selection and maintenance

At present, the power data of road transport vehicles are all matched by the manufacturer, as long as the corresponding power, gear ratio and rear axle speed ratio are selected to meet different load capacities, transportation aging and later maintenance cycles .

For some green transportation, express transportation, and LTL logistics transportation vehicles that are mainly driven at high speed, it is recommended to choose a combination of high horsepower and small speed ratio, so that the vehicle can run fast. For some heavy-duty vehicles in mountainous areas, stability needs to be considered. If you choose high horsepower and high speed ratio, it is better to choose wheel reduction bridge (two-stage reducer).

For off-road vehicles, timber transport vehicles, special operation vehicles, etc., you have to choose four-wheel drive and all-wheel drive vehicles. However, after the steering drive axle is installed, the tire wear and fuel consumption of the vehicle will increase immediately. , the common road transport vehicles are still mainly in the form of front engine and rear drive.

For the maintenance of the axle, as long as it is not carrying too heavy cargo, the axle can be kept in good condition with regular greasing and oil changes normally. Nowadays, the axles of many vehicles are long oil change and maintenance-free, so there is a certain service life limit in addition to the daily wear and tear of the gears, like those vehicles with standard load transportation, they may not need to replace the axles all the time. But for heavy-duty vehicles, it is much higher mechanical wear and tear.

▎Summary

As a very important component of the truck, the axle not only carries all the weight of the truck, but also is responsible for the vehicle steering, driving, braking, balancing and other functions. For the truck driving has a vital role, daily inspection and maintenance can not be missing.The common forms of floating axles are: 6X2, 8X2 models, generally this axle is installed in the front of the drive axle, some models have steering and lifting functions, and some models only have the lifting function, there is no driving function, just play a role in improving the bearing capacity.

The common forms of floating axles are: 6X2, 8X2 models, generally this axle is installed in the front of the drive axle, some models have steering and lifting functions, and some models only have the lifting function, there is no driving function, just play a role in improving the bearing capacity.