Car chassis differential

If the drive wheels on both sides of the drive axle are rigidly connected with a whole shaft, the two wheels can only rotate at the same angular speed. In this way, when the car turns to drive, because the outside wheel is larger than the inside wheel, the outside wheel will produce a slip while rolling, and the inside wheel will produce a slip while rolling. Even if the car is driving in a straight line, the wheel will slide because the road is uneven or although the road is flat but the tire rolling radius is not equal (tire manufacturing error, different wear, uneven load or unequal pressure). When the wheel slides, it not only aggravates tire wear, increases power and fuel consumption, but also makes steering difficult and braking performance worse. In order to prevent the wheels from sliding as much as possible, the structure must ensure that each vehicle can rotate at different angular speeds. Usually the driven wheel is supported by bearings on the mandril, so that it can rotate at any angular speed, and the drive wheel is rigidly connected with two half-shafts, and a differential is installed between the two half-shafts. This differential is also called the interwheel differential. Multi-axle drive off-road vehicles, in order to enable each drive axle to rotate at different angular speeds to eliminate the sliding of the drive wheel on each bridge, some are equipped with an inter-axle differential between the two drive axles. The differential on modern cars is usually divided into two categories according to its working characteristics: gear differential and anti-slip differential. Gear differential When there is a speed difference between the left and right driving wheels, the torque assigned by the differential to the slow driving wheel is greater than the torque of the fast driving wheel. The torque equalization characteristic of the differential can satisfy the normal driving of the car on a good road surface. However, when the car is driving on a bad road, it seriously affects the passing ability. For example, when one driving wheel of a car is stuck in a muddy road, although the other driving wheel is on a good road, the car often cannot move forward (commonly known as skid). At this time, the driving wheel on the muddy road slides in place, while the wheel on the good road is stationary. This is because the adhesion between the wheel and the road on the muddy road is small, and the road can only pass the reaction torque of the wheel on the half shaft, so the torque allocated to the wheel is also small, although the adhesion between the other driving wheel and the good road is large, but because of the characteristics of the average distribution of torque, the driving wheel can only be allocated to the same amount of torque as the sliding wheel. As a result, the driving force is not enough to overcome the driving resistance, the car cannot move forward, and the power is consumed on the sliding drive wheel. At this time, increasing the throttle not only can not make the car move forward, but waste fuel, accelerate the wear of the parts, especially the tire wear. The effective solution is to dig out the mud under the sliding wheel or pad dry soil, gravel, branches, hay and so on under the wheel. In order to improve the passing ability of cars on bad roads, some off-road vehicles and high-end cars are equipped with anti-slip differential. The characteristic of the anti-slip differential is that when one side of the driving wheel slides on a bad road, it can pass most or even all of the torque to the driving wheel on a good road surface, so as to make full use of the adhesion of the driving wheel to generate enough driving force to make the car start or continue to drive smoothly.