The shock absorber is mainly used to suppress the shock and the impact from the road surface when the spring rebounds after absorbing the shock. When passing on uneven roads, although the shock-absorbing spring can filter the vibration of the road, the spring itself will reciprocate, and the shock absorber is used to suppress the jump of this spring.
In the suspension system, the elastic element is shocked to produce vibration. In order to improve the driving comfort of the car, a shock absorber is installed in parallel with the elastic element in the suspension to attenuate the vibration. The shock absorber used in the suspension system of the automobile is mostly hydraulic damping. The working principle of the shock absorber is that when the frame (or body) and the axle are subject to vibration, the piston in the shock absorber moves up and down, and the oil in the shock absorber cavity repeatedly passes through different chambers. The pore flows into another cavity. At this time, the friction between the hole wall and the oil and the internal friction between the oil molecules form a damping force on the vibration, so that the vehicle vibration energy is converted into oil heat, which is then absorbed by the shock absorber and emitted into the atmosphere. When the oil channel cross-section and other factors remain unchanged, the damping force increases or decreases with the relative movement speed between the frame and the axle (or wheel), and is related to the oil viscosity.