What types of carbon brushes are used in brushed motors?

In electric tools, electric brushes are typically referred to as carbon brushes. They are a component of the engine. They function as current commutators in the motor in addition to connecting the armature and the external circuit. The following are the types of carbon brushes.

1. Carbon ink-based brushes (hard brushes)

This kind of brush is a member of the high-resistance electrochemical graphite brush family, which is distinguished by a high contact resistance and effective commutation. Although it has a large friction coefficient and a loose structure, it is employed for DC motors with challenging commutation. The brush needs to be soaked before leaving the factory.

2. Metal graphite brush

It is made of metal and graphite, and the qualities of strong electrical conductivity and good lubricity of graphite are used to change the composition of the two materials to alter the brush's performance. Contact voltage drop, resistance coefficient, and electrical loss are its defining characteristics. Low-voltage AC winding motors and low-voltage high-current motors are the major applications for this brush.

3. Graphite-based brushes (soft brushes)

It is used for large synchronous motors with high linear speed, rolling motors with large instantaneous impact loads, and small and medium-sized DC motors; it has low friction coefficient, good lubricating performance, good current collecting performance, thermal stability, and anti-oxidation performance.

4. Natural graphite brush

This type of brush is utilized for synchronous machine slip rings and AC wound motors with high linear speed and has high contact voltage drop, strong rectification performance, lower current collecting performance than electrochemical graphite brushes, and good lubrication performance;

5. Resin binder graphite brush

This type of brush is typically used in AC commutator motors and is characterized by high resistance, high contact voltage drop, good commutation performance, optimum anti-oxidation and anti-wear performance, but substantial power consumption.

6. Coke-based brushes (medium-hard brushes)

It possesses a specific level of current collecting capability, a decent ability to produce an oxide layer, a substantial contact voltage drop, and good commutation performance.

The above is the introduction about the types of brushed motor carbon brushes shared by Vshida Micromotor. For more information, please feel free to consult us.