Troubleshooting of abnormal sound of the automobile transmission shaft
When the technical condition of the automobile transmission shaft deteriorates, the amplitude of the exaggerated vibration increases, the vibration is severe, and even causes the body to vibrate, and emit an obvious periodic sound, which is called vibration and abnormal noise. The main reason for the vibration and abnormal noise of the drive shaft is that the drive shaft of the car is aggravated by the increase in the vehicle's speed
There are the following aspects.
1. The transmission shaft assembly is out of balance. The assembly error of the transmission shaft assembly exceeds the limit, the size of the parts is not accurate, and the wear and deformation in use will cause the quality of the transmission shaft along the length direction.
Uneven distribution causes unbalanced transmission. The unbalanced transmission shaft will generate additional exaggerated moments during operation, and the effect of additional exaggerated moments will not only make
The impact and sound of the matching parts will also enhance the exaggerated vibration of the transmission shaft, making the vibration and abnormal noise of the transmission shaft more obvious.
2. Universal joint damage
The main damage of the universal joint in use is the wear of the cross shaft journal and end face, the wear of the needle roller and the bearing seat hole, etc. Damage to universal joint components +
The word shaft is loosely matched to produce swing and axial movement, which not only makes a knocking sound during work but also weakens the anti-exaggeration rigidity of the drive shaft. transmission shaft
The center of mass is further off the axis of rotation, which increases chatter and rattle.
3. The transmission shaft and sliding fork are damaged. The shaft tube of the transmission shaft is bent, that is, the amplitude of the bending vibration of the transmission shaft is increased, which can increase the centrifugal force, resulting in strong vibration and abnormal noise. transmission
The key teeth of the shaft and the keyway of the sliding fork are worn. Due to the loose fit, there will be a knocking sound during work, and it will also weaken the bending resistance of the drive shaft and strengthen the
Vibration and rattling.
4. The installation position at both ends of the transmission shaft is changed
For the unequal angular velocity universal joint drive shaft, to reduce the vibration of the drive shaft and ensure the uniform rotation of the drive axle gear, the following two conditions must be met:
condition:
1) The universal joint forks at both ends of the transmission shaft should be located in the same plane;
2/ The two included angles of the input shaft, output shaft, and transmission shaft should be equal. When the drive shaft is in use, due to the wear of the key teeth of the drive shaft and the keyway of the sliding fork, the
The loose fit between the knuckle cross shaft journal and the needle roller will destroy the first condition; and the poor installation of the transmission shaft, the change of the technical condition of the elastic suspension, and the transmission
Abrasion of the input shaft and output shaft of the moving shaft to change the installation position will destroy the second condition. With the destruction of the constant speed transmission condition, it will make
The main reduction gear of the drive axle produces an impact, which causes the drive shaft to run unstable, and enhances vibration and abnormal noise.
5. The critical speed of the drive shaft is reduced. The maximum speed of the drive shaft is generally 0.7 times the critical speed. However, due to the damage to the dynamic balance of the transmission shaft, the damage to the universal joint and the
Loose support bearings, etc., will reduce the critical speed of the transmission shaft. When the critical speed is reduced to the speed of the drive shaft, the drive shaft will
Easy to resonate. The amplitude of the transmission shaft resonance is the largest, and the vibration is severe, which often causes the transmission shaft to break.
