Inside DC motors, a rotor with a coil wound around it is installed in the center, and a stator polarized into N and S poles is installed around it.
When an electric current is applied to the DC motors, a magnetic field is generated in the coil according to Fleming’s law. When the magnetized rotor poles and stator poles are the same, a repulsive force is induced, and when they are opposite poles, an attractive force is induced, causing the rotor to rotate.
Reversing the current flowing through the rotor changes the attractive and repulsive forces, which are repeated alternately to rotate the rotor in a fixed direction. The power required for magnetization is provided by a conductor brush in contact with a part called the commutator.
Due to its simple structure, a motor with high output torque efficiency can be manufactured cheaply. However, because the commutator and brushes rotate in contact with each other, the brushes wear out. Therefore, for small brushed DC motors, brush life is motor life.
Post time: Apr-01-2024