Imbalance
Imbalance in the propeller shaft causes vibration or noise, like in tires. The propeller shaft turns faster than tires by the gear ratio of the differential gear. Therefore, the frequency of (more…)
Vibration
Tire Uniformity Vibration and Sounds
Tire uniformity refers to uniformity of weight, dimensions and rigidity.
However, since uniformity of weight is ordinarily called “wheel balance” and uniformity of dimensions is called “run-out” uniformity (more…)
Run-out Vibration and Sounds
Since a tire is made by bonding together rubber, there is a in difference in the rubber thickness, the circumference of the tire is not a perfect circle.
Even if the tire is perfectly circular, if the (more…)
Wheel Balance Vibration and Sounds
Due to the weight unbalance of the rotating object, a centrifugal force is generated during rotation, which results in a vibrating force.
This vibrating force increases in proportion to the square of (more…)
Tires Vibration and Sounds
The vibrating force caused by tires can be classified into two cases; the tire itself generates the vibrating force and uneveness on the paved road cause a vibrating force.
Tire itself generates vibrating (more…)
Other Components of Engine Vibration and Sounds
Engine Mounts
Although engine mounts are relatively small, they are important in controlling NVH.
They link the vehicle body to the engine, the largest source of vibration. It is through these mounts (more…)
Engine Intake and Exhaust System Vibration and Sounds
Intake System
Intake noise includes the pulsating sound of the air taken in and the resonance sounds.
A pulsating sound has a relatively high frequency. It is determined by the air volume, shape of the (more…)
Source of Automotive vibration Generation
As typical examples of vibrating force in a vehicle, there are the following: combustion pressure or torque fluctuation in the engine, unbalanced tires, rough road, imbalance or joint angle in the propeller (more…)
Transmission and prevention Vibration and Noise
Methods for preventing vibration or noise are as follows:
Removing the vibrating force
Stopping the resonance
Stopping the transmission
Preventing vibration and noise
etc.
Vibration or noise can (more…)
Method of Indicating Vibration, Sound, and Noise
Transmitting system
A vibration caused by a vibrating force and amplified by resonance causes the O-ring of the exhaust pipe and engine mounts to vibrate, transmitting a noise to the cabin. The passage (more…)