Carbon brush is a device which conducts current between stationary wires and moving parts,most commonly in a rotating shaft. it's a sliding contact used to transmit electrical current from a static to a rotating part, in a motor or generator, and as regards DC machines, ensure a spark-free commutation. typical applications include electric motors, alternators and electric generators.
Carbon brushes are maintained by brush-holders to be in permanent contact with the slip ring assembly or with the commutator.
Carbon Brushes are used in general industrial such as DC motors, Electrical trains, Wind-generated power. industrial carbon brushes are used on large commutator machines, in which the current between the rotor and external circuit is periodically reversed. These include AC and DC motors, slipring rotors, traction motors, turbogenerators, windmills, hydro power stations and steel, cement and paper mills. Industrial carbon brushes also can be used to power battery-driven cars, cable cars and trolley buses, and they are often used in construction vehicles such as forklift trucks and cranes. Brushes connect the generator to the rotor through the commutator, which has copper segments, or lands. The brushes bear the brunt of wear and tear between the rotating rotor and the non-moving generator while conducting electricity between them. Industrial brushes are specially designed to withstand extreme temperatures.
The home application of carbon brushes as the power tools like washing machines and disk grinders.carbon brushes are a common component in household appliances such as power tools, gardening equipment and office equipment. Vacuum cleaner turbines, hair and hand dryers, and washing and drying machines are also common applications of this type of carbon brush, which is generally much smaller than its industrial or automotive counterparts. Micro-carbon brushes, for example, are precision parts designed for toys, electric razors, and audio and video equipment. In such small dimensions, carbon brushes are often placed inside tiny battery-operated mini-motors designed to transmit power silently and with the least amount of friction to moving parts such as wheels and razors.
As to automotive application of carbon brushes, we will think of automobiles and forklifts.cars generally use small and auxiliary carbon brushes for DC motors, starters and alternators. Alternators are devices that convert mechanical energy to electrical energy. They consist of a wire-coiled rotor that produces a magnetic field when a current runs through it. Automotive carbon brushes are used to supply the current to the wire coil in the alternator. Automotive carbon brushes can be found in most passenger vehicles, motorcycles, trucks and oil- and diesel-fueled cars. Even smaller, specially designed carbon brushes are used in steering wheels and contacts for airbags.
The performance and application of carbon brushes in the pulp and paper environment. direct current (DC) motors are used extensively throughout the pulp and paper industry. the motors are used in various applications such as fan pumps, press and winder motors. The maintenance requirements of the motors are different for each application. An important maintenance function regularly performed is the inspection of carbon brushes and commutators. Carbon brushes are critical to the operation of the paper machine with DC motors. Worn or failed brushes can make a paper machine inoperable and cost thousands of dollars per hour.