The pulley is widely used in all walks of life. When installed on the engine, it has a certain damping effect when running on machinery. The reasons are as follows:

In order to reduce the impact vibration caused by the working of the engine, it is on the ordinary full iron belt wheel, in the middle ring cut into two parts inside and outside, in the middle and outside two parts of the middle (the gap) filled with rubber, that is, a rubber layer. In this way, the power of the engine is first transmitted to the inner ring of the belt pulley, and then to the damping rubber in the middle layer, and then from the damping rubber to the outer ring. In this way, the vibration and noise of the engine will be reduced in the outer ring of the iron because of the "slow layer" of the rubber. Thus reducing noise and relieving vibration (impact force).

The power of the crankshaft output is transferred to the compressor, the direction support pump, the pump, the generator and so on, and the crankshaft output power is transferred to the camshaft to drive the timing system. A part of the engine with a balancing shaft is also driven by a belt to balance the shaft.