Why brushes are used in motors

The continued need for brushes is a serious issue considering the wide availability of carbon brushes in case there is a need to have these replaced. Although a carbon brush is susceptible to wear, these components are quite dependable. In fact, with proper care, usage, and maintenance, you can prolong the lifespan of carbon brushes. The better the condition of the brushes, the better the performance and efficiency of the dc motor.

The brush is also responsible for changing the course of current in the conductors during the rotation process. Aside from these functions, the carbon brush keeps the surface of the slip ring, or the commutator, clean.

Since these brushes have a protective carbon film, it ensures a close contact as the machine operates. Thus, this prevents the motor, or commutator, from wearing out. This barrier is why the commutator maintains its smoothness and optimal condition.

Carbon is the best material for these brushes. Carbon contains all the electrical, physical, and mechanical properties suitable for protecting the motor from damages. Track certain sensitive areas that contact carbon brushes to ensure the proper condition of a carbon brush. Rings with a high peripheral speed tend to have a helical groove that promotes the stability of the brush. Chamfer the edges to make sure the carbon brush does not wear out.

The same holds true with commutators. Rectify any abnormality at the surface to prevent brush damages while prolonging its lifespan. Immediately address any issues with vibrations due to poor alignment, defective running, or improper balance.

These conditions prevent good contact between the commutator and the carbon brush. Alexander Graham Bell was a Scottish-born American inventor and scientist. Bell was born on March 3, , in Edinburgh, Scotland. An electric motor is a machine that converts electrical energy to mechanical energy.

An electric generator is a machine that converts mechanical energy to electrical energy. The shaft of an electric motor is driven by a magnetic force which is developed between the armature and field. You can use just about any motor to generate electric current, if it is wired correctly and you follow specific rules for its use.

Modern AC induction motors are quite simple to wire as alternating current generators, and most will begin generating electricity the first time you use them. Electric generators work on the principle of electromagnetic induction. A conductor coil a copper coil tightly wound onto a metal core is rotated rapidly between the poles of a horseshoe type magnet. The magnetic field will interfere with the electrons in the conductor to induce a flow of electric current inside it.

There are two fundamental types of generators known as AC alternating current and DC direct current generators. While the technique of producing electricity is the same in both types, AC and DC power become different in terms of their applications — the way in which loads receive electric power. By continuing to use this website, you are agreeing to the use of cookies.

Further information is available in our data privacy notice. Are you looking for product information? Read now: All about drives in e-mobility. Questions about your drive?

To know the answers to these questions, we need to know how DC motors operate. All DC motors are built of 3 main sub-assemblies; the stator, the rotor and the brush system. The main body of the motor is the stator, consisting of the permanent magnet which is centrally located around the shaft, within the housing and the mounting flange. The permanent magnet is diametrically magnetized with a North Pole and South Pole.

The magnet has a bore hole for the shaft of the motor. The magnetic induction comes out the North Pole into the housing and out into the magnets South Pole. The housing is made of magnetically conductive material and acts as magnetic return. There is an air gap between the permanent magnet and the housing.

This creates a strong magnetic field to ensure the winding produces as much force as possible. Too much of an air gap weakens the magnetic flux as air is a bad magnetic conductor. Finding the optimum air gap is always difficult as it depends strongly on the properties of the permanent magnet.

Keeping the air gap too narrow only allows a thin winding, which restricts lower current density and produces a reduced power density. The rotor is made of the winding and the commutator and this allows the shaft to rotate.