Electric Motor Brushes – What Are They

electric motor brushes

What are electrical motor brushes? Well, it is a metal tool that is used in motors and generators to help move the power windings. Electrical motor brushes have different parts such as a rotor, a bunch of insulated balls (which may be made of steel, brass, or other metals), and a commutator. The commutator separates the flow of electricity in the windings from the outside noise. It also separates the force of the findings against the resistance of the air. These things work together to make a powerful motor.

Electric Motor Brush Made Of-

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An electric motor brush can have one or several insulated balls and one or several shunts or terminals attached to them. Usually there are several different carbon brushes on a motor or generator. In some generators there are three of them instead of just one. Although the original, traditional brushes were typically made of brass, carbon soon became the most preferred, electrical motor brush material due to its low resistance, high friction, and ability to withstand arcing.

Besides using carbon there are other types of electrical motor brushes. One of these is the magnetic brush. This is used to induce a magnetic field into a commutator. By doing so, the flow of current is smoother and does not have any “back talk”, which is caused by the resistance caused by the metal. Another popular type of electric motor brushes is the electrostatic brush.

Working Of Electrostatic Electric Motor Brushes

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Electrostatic electric motor brushes use an extremely small amount of voltage to induce a charge in the commutator. Because the small amount of voltage is lower than the electrical current flowing through the brushes, there is less resistance. But, there is one downfall to these brushes: they tend to wear out much more quickly than the regular carbon brushes. Also, they are limited in their effectiveness by the fact that they work best in metals that conduct electric currents better.

There are two types of commutators on electric motors. One is called a rotor, which runs parallel to the commutator. The commutator can either be made of steel or aluminum. The second type of commutator is called a blade. This type of commutator is not as common.


Examples of these include steel, copper and brass. These are often used in air engines. On the other hand, there are some brushes that are used in electrical motors. Examples of these include nylon, carbon and graphite.

Most electric motor brushes have a clutch system. This system allows you to adjust the pressure and speed of the brushes automatically. They also generally contain a safety switch which stops the motor if it should happen to slip or become stuck. If you use a small electric motor brush you may want to consider purchasing one with a safety switch as well. Safety switches prevent the brushes from starting if they become stuck or slip off the commutator.

Bottom Line

Some brushes use solvents as an abrasive to remove stubborn contaminants from their commutators. In order to work this way the brush must be very hard and stiff. Many brushes are designed to use either carbon or graphite as their commutator. Some brushes are made from materials that only conduct heat, this includes many types of wood. In order to get the best cleaning power you should purchase commutator that fits your needs.

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