Application and development trend of air spring

1. Introduction of air spring
Air spring is an elastic element which uses the reaction force of compressed air inside the rubber airbag as the elastic restoring force. It has the following characteristics: 1) the air spring has nonlinear characteristics, and its characteristic curve can be designed into an ideal shape; 2) the air spring has light weight and small internal friction, and has good vibration isolation and noise elimination ability for high frequency vibration; 3) the stiffness and bearing capacity of the air spring can be adjusted by adjusting the internal pressure of the rubber bag; 4) the manufacturing process of the air spring is complex and the cost is high. According to the deformation mode of air spring, it can be divided into three types: capsule type, membrane type and mixed type.

The elastic deformation of the bag type air spring mainly depends on the bending of the rubber bag; the membrane air spring mainly relies on the curling of the rubber air bag to obtain the elastic deformation; the hybrid air spring has both the above two deformation modes. According to the different curvature number of rubber bag, the air spring can be divided into single curve, double curvature and multi curve air spring. The structure of membrane air spring is to place a cylindrical rubber air bag between the cover plate and the base, and realize the overall expansion and contraction through the deflection deformation of the air bag. In the normal working range of membrane air spring, the change of spring stiffness is smaller than that of capsule type air spring. At the same time, the change rate of effective area can be controlled by changing the shape of base, so as to obtain ideal elastic characteristics.

The change rate of the effective area of the membrane air spring is also smaller than that of the bag spring. Therefore, the membrane air spring can obtain a lower natural frequency when the auxiliary air chamber is small. According to the connection mode between the rubber airbag stop and the interface, it can be divided into constraint mode and free mode air spring. The air spring seal in restraint mode is usually clamped and sealed by bolt; the air spring in free mode is sealed by pressure in the air bag. The base is mostly made of deep drawing steel plate or light cast steel, and the surface is chrome plated to reduce the friction between the air bag and the base.