A carbon brush is a device that transmits energy or signals between the fixed part and the rotating part of a motor or generator or other rotating machinery. It is generally made of pure carbon plus a coagulant and acts on the commutator of a DC motor. The application materials of carbon brushes in products mainly include graphite, greased graphite, and metal (including copper, silver) graphite. The appearance of the carbon brush is generally a square, which is stuck on a metal bracket. There is a spring inside to press it on the rotating shaft. When the motor rotates, the electric energy is sent to the coil through the commutator. Because its main component is carbon, it is called carbon. Brush, it is easy to wear. Therefore, regular maintenance and replacement are required, and carbon deposits are cleaned up.