What's the difference between a traditional transmission shaft and a new one?

Automobile transmission shaft structure. The transmission shaft consists of shaft tube, telescopic sleeve and universal joint. The telescopic sleeve can automatically adjust the change of the distance between the transmission and the drive axle. Universal joint is to ensure the change of the included angle between the transmission output shaft and the drive axle input shaft, and realize the equal angular velocity transmission of the two shafts. Universal joint, universal joint is the key component of automobile transmission shaft. A car is a moving object. In a rear-drive car, the engine, clutch and transmission are installed on the frame as a whole, while the drive axle is connected with the frame through an elastic suspension, and there is a distance between them, so they need to be connected. When the car is driving, the uneven road surface jumps.

1. Function: Universal universal joint consists of spider, spider bearing and flange fork. Universal joint is the key component of automobile transmission shaft. On vehicles with front engine and rear wheel drive, the universal joint transmission shaft is installed between the output shaft of the transmission and the input shaft of the main reducer of the drive axle; Vehicles with front engine and front wheel drive omit the transmission shaft, and a universal joint is installed between the front axle and the wheel, which is responsible for both driving and steering. When the vehicle is running, the included angle and distance between the output shaft of the transmission and the input shaft of the main reducer of the drive axle will change due to uneven road surface, load change or different installation positions of the two assemblies. Therefore, a "variable strain" device is needed to solve this problem, so there is a universal joint.

2. Transmission characteristics: In the automobile with front engine and rear wheel drive (or all-wheel drive), due to the deformation of the suspension during the movement of the automobile, there is often relative motion between the input shaft of the main reducer of the transmission shaft and the output shaft of the transmission (or transfer case). In addition, in order to effectively avoid some mechanisms or devices (which can not realize linear transmission), there must be a device to realize the normal transmission of power, so universal joint transmission appeared. Universal joint drive must have the following characteristics: to ensure that the relative position of two connecting shafts changes within the expected range and can transmit power reliably; Ensure that the two connected shafts can run smoothly. The additional load, vibration and noise caused by the included angle of the universal joint should be within the allowable range; High transmission efficiency, long service life, simple structure, convenient manufacture and easy maintenance. For automobiles, because the output shaft of a spider universal joint does not rotate at the same speed relative to the input shaft (with a certain angle), it is necessary to use double universal joints (or multi-universal joints) for transmission, arrange the two universal joint forks connected with the transmission shaft on the same plane, and make the angles of the two universal joints equal. This is very important. The included angle of the universal joint should be minimized in the design.

3. Telescopic sleeve, the traditional structure of transmission shaft telescopic sleeve is to weld spline sleeve and flange fork together, and weld spline shaft on transmission shaft tube. The new transmission shaft changes the traditional structure, welding the spline sleeve and the transmission shaft tube into a whole, and making the spline shaft and the flange fork into a whole. Changing rectangular spline into involute short spline with large pressure angle not only increases strength, but also facilitates extrusion forming, which meets the needs of high torque working conditions. The tooth surfaces of the telescopic sleeve and the spline shaft are integrally coated with a layer of nylon material, which not only improves the wear resistance and self-lubrication, but also reduces the damage of impact load to the transmission shaft and improves the buffering capacity. A tubular sealing protective sleeve is added to the flange spline shaft of this transmission shaft, and two polyurethane rubber oil seals are arranged at the end of the protective sleeve, so that a completely sealed space is formed in the telescopic sleeve, and the telescopic spline shaft is not corroded by external dust, which is dustproof and antirust. Therefore, when assembling, the spline shaft and the sleeve are coated with grease at one time, which can completely meet the use requirements, and lubrication of the oiler is not needed, thus reducing the maintenance content.

4. The design of the shaft sleeve is to reduce the friction and wear when the shaft moves. Its basic use is the same as that of bearings, and its relative cost is relatively cheap, but its friction resistance is large, so it will only be used in some parts. Bushings are mostly made of copper, but there are also plastic bushings. Most of the shaft sleeves are placed in the shaft and supporting structure, and they are very close to the supporting structure. Only the shaft can rotate on the shaft sleeve. When assembling the shaft and sleeve, lubricant will be added between them to reduce the friction generated when they rotate.