A SHOCK to the system - The purpose of an energy-absorbing device is to stop a moving load with minimum load rebound, minimum shock to the load, and minimum shock to surrounding equipment

摘要

In motion control, it is often desirable - or necessary - to stop a moving load smoothly. A rubber snubber, a compression spring, and a dashpot all can accomplish this, by absorbing energy. The snubber and spring store energy, and release it after they are compressed, resulting in a rebound. A dashpot is a fluid-filled cylinder with an opening through which fluid may escape in a controlled manner. Any force acting against the piston in the cylinder encounters high resistance from the fluid at the beginning of the stroke, then much less as the piston retracts. However, none of these three items dissipate the energy uniformly. The impact of a moving load against a resisting force produces peak forces that are transmitted to plant equipment, or to the load itself. In order to dissipate the energy uniformly, the use of a shock absorber is required.