DC Brush Electric Motors

A DC motor is a type of electric motor that converts electrical energy into mechanical energy using direct current.

The SERMAT DC motor has a wide range of applications in a variety of appliances and tools. The speed of DC motors can be controlled by varying the supply voltage using a frequency or speed inverter. The most common voltages are 12 V and 24 V.

Rotor

The rotor is the moving part of the DC motor. It consists of wire coils wound around an iron core. When current flows through these coils, it creates a magnetic field that interacts with the magnetic field of the stator, causing the rotor to rotate.

Stator

The stator is the fixed part of the motor. It can be made up of wire coils or permanent magnets that create a constant magnetic field. The magnetic field of the stator interacts with the magnetic field of the rotor to produce movement.

Brushes and commutator

The brushes in a DC electric motor are carbon or metal devices that rub against the commutator, a segmented cylindrical component located on the rotor shaft. The commutator changes the direction of the current in the rotor coils every half turn, allowing the rotor to continue turning in the same direction.

Applying the current

When direct current is applied to the rotor coils via the brushes and commutator, it creates a magnetic field around the coils.

Interaction of magnetic fields

The magnetic field of the rotor interacts with the magnetic field of the stator. According to Lorentz's law, a force is exerted on the rotor conductors, causing the rotor to rotate.

Switching

As the rotor rotates, the brushes touch different sections of the commutator, changing the direction of the current in the rotor coils. This keeps the rotor's magnetic field in an optimum position relative to the stator field, ensuring continuous rotation.

DC motors are used in many applications because of their ability to deliver high torque at low speeds and to offer precise speed control. They are found in electromechanical systems such as electric vehicles, industrial control systems and lifting and handling equipment.

DC motors provide easy control of speed and torque. They respond quickly to load variations. However, brush and commutator wear requires regular maintenance of these electromechanical systems.