A DC motor makes use of the principle of polarities of the North and South poles. It is the interaction between the conductor and magnetic field that leads to the rotational motion as output. There are six parts in a DC motor, namely, the axle, stator, commutator, rotor, brushes and field magnets. The permanent magnets or electromagnets create the external magnetic field. The stationary part of the motor is called the stator and windings on a core comprise the rotor. The rotation of the rotor, and by extension the axle and cmmutator, is with respect to the rotation of the stator. During this process, the DC motor speed control is achieved.
There are different kinds of DC motors like brushed motors, permanent magnet motors and universal motors. Of these, the brushed motors are of three types: shunt wound, series wound and separately excited. The permanent motor magnets are of two types: rotor magnets and field magnets. Universal motors are used in common household appliances like food mixers, vacuum cleaners and power tools. The DC motor speed control is very poor in the series motor but they are good for varied speed operations. DC motors are particularly good for high traction applications.
In rotor magnets, the commutator is eliminated altogether, while using a fixed shunt current. They make use of permanent magnets without any rotor windings at all. DC motors are very essential in a lot of applications, both major and minor, so it pays to buy them from a reputed company like Teco Electric Co. Ltd.