1. Simple hydraulic shock absorber
The working principle of hydraulic shock absorber is:
When the frame and the axle reciprocate relative to each other and the piston reciprocates in the cylinder, the oil in the shock absorber housing flows back and forth between the two isolated cavities through some narrow pores. The damping force is formed by the friction between the hole wall and the oil and the friction within the liquid molecule, which converts the mechanical energy of the vehicle body vibration into heat energy, which is absorbed by the oil and the shell, and dispersed into the atmosphere. The damping force is controlled by the area of the oil passage, valve spring stiffness and oil viscosity.
2. Gas-filled shock absorber
Its structural feature is that a movable piston is installed in the lower part of the cylinder, and the closed air chamber 1 formed by the floating piston and one end of the cylinder is filled with high-pressure (2-3MPa) nitrogen. Above the floating piston is the shock absorber oil. The floating piston is equipped with a large-section shaped sealing ring, which completely separates the oil and the gas, so the piston is also called the air-sealed piston. The working piston is equipped with a compression valve and an expansion valve that change the cross-sectional area of the channel according to its moving speed. Both valves are composed of a set of spring steel sheets with the same thickness and different diameters arranged from large to small.
3. Adjustable resistance shock absorber
In terms of ensuring that the suspension system has good vibration characteristics under various working conditions, the damping force of the shock absorber should be variable.