A damper is a device that provides resistance to movement and reduces movement energy. The use of damping to absorb energy is not a new technology. In the aerospace, aviation, military, gun, and automobile industries, various dampers (or shock absorbers) have been used to reduce vibration and energy. Since the 1970s, people have gradually transferred these technologies to structural projects such as construction, bridges, and railways, and their development has been very rapid. Especially the hydraulic viscous damper with a history of more than 50 years, before it was accepted by the structural engineering community in the United States, it experienced a lot of experiments, rigorous review, and repeated demonstrations, especially the long process of earthquake tests.
A device capable of quickly stopping the movable part of the meter in a stable deflection position. In seismic instruments, a damper is used to absorb the natural vibration energy of a vibration system, and its damping force is generally proportional to the speed of the vibration system. There are three types of liquid dampers, gas dampers and electromagnetic dampers. The damper plays an important role in compensating the small friction and air resistance in the vibration system of the pickup and improving the frequency response