Views: 1 Author: Site Editor Publish Time: 2021-12-06 Origin: Site
Nowadays, cars have penetrated into all aspects of life. When driving on the road, I wonder if you have ever thought about the question: Why is the power still output to the wheels when the car is turning?
In fact, in order to cope with various road conditions, vehicles need to steer wheels to change the trajectory of motion, and at the same time, it is also necessary to ensure that the power can still be transmitted to the wheels, so universal joints came into being.
The so-called universal joint refers to the use of ball-type devices to realize the shaft power output mechanism in different directions. A bit like the joints on the limbs of the human body, it allows the angle between the connected parts to vary within a certain range. The combination of universal joint and drive shaft is called universal joint transmission. On the front-engine rear-wheel drive vehicle, the universal joint transmission is installed between the transmission output shaft and the drive axle final drive input shaft; while the front-engine front-wheel drive vehicle omits the transmission shaft, and the universal joint is installed Between the front axle half shaft and the wheels that are responsible for both driving and steering.
Classification of universal joints
According to whether the universal joint has obvious elasticity in the torsion direction, it can be divided into rigid universal joint and flexible universal joint. Rigid universal joints can be divided into unequal velocity universal joints, quasi-constant velocity universal joints and constant velocity universal joints.
Flexible universal joints rely on the elastic deformation of elastic parts to ensure that no mechanical interference occurs during transmission between the two shafts. They are generally used in transmission situations where the angle between the two shafts is not more than 3°~5° or a slight axial displacement. Without introduction, let us start with the cross-shaft universal joint. The cross-shaft universal joint is a variable speed universal joint widely used in automobiles. It allows the maximum angle of intersection of two adjacent shafts to be 15゜～20゜.
The cross shaft universal joint consists of a cross shaft, two universal joint forks and four needle bearings. The holes on the two universal joint forks are respectively sleeved on the two pairs of journals of the cross shaft. In this way, when the driving shaft rotates, the driven shaft can rotate with it, and it can swing in any direction around the center of the cross shaft, so that the need for simultaneous changes of the included angle and distance can be met. A needle roller bearing is installed between the cross shaft journal and the universal joint fork hole, and the outer ring of the needle roller bearing is axially positioned by the snap ring.