DC gear motors
Introduction
The direct current motor, also called direct current motor, CC motor or DC motor (by the initials in English: direct current), is a machine that converts electrical energy into mechanical energy, causing a rotary movement, thanks to the action of a magnetic field.
The components of a DC motor are divided into two parts:
- Stator: part that provides mechanical support to the device and contains the poles of the machine, which can be windings of copper wire on an iron core or permanent magnets.
- Rotor "Rotor (electric machine)"): is a component generally cylindrical in shape, also wound and with a core, fed with direct current through the collector formed by thins. The thinners are generally made of copper and are in alternating contact with the fixed brushes.
The main drawback of these motors is the costly and laborious maintenance, mainly due to the wear and tear that the brushes suffer when they come into contact with the brushes. The brushes of low-power motors are made of graphite. On the other hand, those that require high currents, such as vehicle starter motors, are manufactured with an alloy of graphite and metal.
Some special applications of these motors are: linear motors, servo motors, stepper motors or when they exert traction on a rail. In addition, there are brushless DC motors used in airplane modeling due to their low torque and high speed.
It is possible to control the speed and torque of these motors using DC motor control techniques.
Working principle
Contenido
El principio de funcionamiento básico de un motor de CC se explica a partir del caso de una espira de material conductor inmersa en un campo magnético, a la cual se le aplica una diferencia de potencial (o voltaje) entre sus extremos, de forma que a través de la misma circula una corriente I.
Para este caso, la espira constituye el rotor del motor y los imanes que producen el campo magnético constituyen el estátor.
Entonces, dado que cuando un conductor, por el que pasa una corriente eléctrica, se encuentra inmerso en un campo magnético, este experimenta una fuerza según la Ley de Lorentz. Dicha fuerza, denominada Fuerza de Lorentz, es perpendicular al plano formado por el campo magnético y la corriente, y su magnitud está dada por:.