What's the structure of DC motor?

The basic structure of a DC motor includes armatures, field magnets, slip rings, and brushes.

Armature: A multi-turn coil can be wound around a soft iron core that rotates around its axis.
Field magnet: A strong permanent magnet or electromagnet that generates a magnetic field.
Collector ring: the coil is connected at both ends to two semicircular collector rings, with the coil rotation, for changing the current direction of the converter. Each half turn (180 degrees), the current direction of the coil is changed once.

Brush: usually made of carbon, slip ring contact fixed position brush, to connect to the power supply.

The advantage of a DC motor is that it is simple in terms of speed control. It only needs to control the voltage to control the speed. However, such a motor should not be operated under high temperature and flammable conditions. Moreover, since the motor needs a carbon brush Commutator components (brush motor), so need to regularly clean the dirt generated by carbon brush friction.