Working principle of two-way action cylinder shock absorber
In the compression stroke, the vehicle wheel is moved closer to the vehicle body, and the shock absorber is compressed, at which time the piston inside the shock absorber moves downward. The volume of the lower chamber of the piston is reduced, the oil pressure is increased, and the oil flows through the flow valve to the chamber (upper chamber) above the piston. The upper chamber is occupied by a part of the piston rod, so that the increased volume of the upper chamber is smaller than the volume of the lower chamber, and a part of the oil then pushes the compression valve back to the storage tank. The oil savings of these valves create a damping force for the suspension to be subjected to compression motion. When the shock absorber is in the extension stroke, the wheel is equivalent to being away from the vehicle body, and the shock absorber is stretched. At this time, the piston of the damper moves upward. The oil pressure in the upper chamber of the piston rises, the circulation valve closes, and the oil in the upper chamber pushes the extension valve into the lower chamber. Due to the existence of the piston rod, the oil flowing from the upper chamber is insufficient to fill the increased volume of the lower chamber, and the main chamber generates a vacuum, and the oil in the storage cylinder pushes the compensation valve 7 into the lower chamber. supplement. Due to the throttling action of these valves, the suspension acts as a damping force during the extension movement.
Since the stiffness and preload force of the extension valve spring are designed to be larger than the compression valve, under the same pressure, the sum of the passage area of the extension valve and the corresponding normally-pass gap is smaller than the sum of the cross-sectional areas of the compression valve and the corresponding normally-pass gap channel. This makes the damping force generated by the tension stroke of the shock absorber larger than the damping force of the compression stroke, and achieves the requirement of rapid shock absorption.