The transmission shaft is composed of a shaft tube, a telescopic sleeve and a universal joint. The telescopic sleeve can automatically adjust the change of the distance between the transmission and the drive axle. The universal joint is to ensure the change of the angle between the output shaft of the transmission and the input shaft of the drive axle, and to achieve the equal angular speed transmission of the two shafts
Gimbal
The universal joint is a key component on the automobile transmission shaft. The car is a moving object. In the rear-drive car, the engine, clutch and transmission are installed on the frame as a whole, and the drive axle is connected to the frame through an elastic suspension. There is a distance between the two and they need to be connected. The bumpy road surface caused by uneven running of the car.
Generally, the universal joint is composed of a cross shaft, a cross bearing and a flange fork. The universal joint is a key component on the automobile transmission shaft. On vehicles with front-engine rear-wheel drive, the universal joint drive shaft is installed between the transmission output shaft and the input axle of the transaxle main reducer; while with front-engine front-wheel drive vehicles, the drive shaft is omitted and the universal joint is installed Between the half axle of the front axle and the wheels that are responsible for both driving and steering. When the vehicle is running, the uneven road surface will jump, the load change or the difference between the installation positions of the two assemblies will change the angle and distance between the transmission output shaft and the input shaft of the main reducer of the drive axle. Therefore, a "to change "Strain" device to solve this problem, so there is a universal joint.
On cars with front- and rear-wheel drive (or all-wheel drive) of the engine, due to the suspension deformation of the car during the movement, there is often relative movement between the input shaft of the main reducer of the drive shaft and the output shaft of the transmission (or transfer case). In addition, in order to effectively avoid certain mechanisms or devices (can not achieve linear transmission), there must be a device to achieve the normal transmission of power, so there is a universal joint transmission. The universal joint transmission must have the following characteristics: a. Ensure that the relative position of the connected two shafts can reliably transmit power when the relative position changes within the expected range; b. Ensure that the connected two shafts can operate evenly. The additional load, vibration and noise due to the angle of the universal joint should be within the allowable range; c. The transmission efficiency is high, the service life is long, the structure is simple, the manufacturing is convenient, and the maintenance is easy.
For automobiles, since the output shaft of a cross shaft universal joint rotates at a different speed relative to the input shaft (with a certain included angle), a double universal joint (or multiple universal joints) must be used for transmission. And the two universal joint forks connected with the transmission shaft are arranged on the same plane, and the angle between the two universal joints is equal. This is very important. The angle of the universal joint should be minimized during design.
Telescopic sleeve
The traditional structure of the transmission shaft telescopic sleeve is to weld the spline sleeve and the flange fork together, and weld the spline shaft to the transmission shaft tube. The new type of transmission shaft changes the traditional structure, welds the spline sleeve and the transmission shaft tube into one, and makes the spline shaft and flange fork into one. And the rectangular tooth spline is changed into a large pressure angle involute short tooth spline, which not only increases the strength but also facilitates extrusion forming, and adapts to the needs of high torque working conditions. The tooth surface of the telescopic sleeve and the spline shaft is coated with a layer of nylon material, which not only increases the wear resistance and self-lubricity, but also reduces the impact of the impact load on the transmission shaft and improves the buffering capacity.
This type of transmission shaft adds a tubular sealing protective sleeve outside the flange spline shaft, and two polyurethane rubber oil seals are provided at the end of the protective sleeve, so that a fully sealed space is formed in the telescopic sleeve to make the telescopic spline The shaft is not eroded by external dust, not only dustproof but also rustproof. Therefore, the grease can be applied to the spline shaft and sleeve at one time during assembly, which can fully meet the requirements of use, without the need for oil nozzle lubrication, reducing the maintenance content.
Bushing
It is designed to reduce friction and wear during shaft movement. The basic use is no different from bearings, and the relative cost is relatively cheap, but the friction resistance is large, so it will only be used on some parts. Most of the bushings are made of copper, but there are also bushings made of plastic. The shaft sleeve is mostly placed in the shaft and the supporting structure, and is very close to the supporting structure, only the shaft can rotate on the shaft sleeve. When assembling the shaft and the sleeve, lubricant will be added between the two to reduce the friction generated when they rotate.