Motors with or without brushes?

Which are the right motor types for the correct application?

The application is usually defining the proper selection of a motor type in the design phase of a product, machine or tool.

Brushed Motor

Carbon brushes are used as gliding contacts in an electric motor or generator and are the connection from stator to rotor. These brushes are wearing and need continuous maintenance to keep the motor functional and operational. The wear causes particle distribution in the area. Thus, these motors are unsuited in the textile industry, in cleanrooms or in facilities where optics or optical equipment is used or produced.

If there are other electrical pieces of equipment in the area or even a laboratory that requires EMF protection, these motors often cause electrical interferences and are not suitable in these environments. These motors can cause electrical sparks and are inadequate for intrinsically safe areas.

The question arises: Where does it make sense to use this technology?

The motors are less expensive as they do not need any external control unit. Voltage controls the operation of these motors, and high speed (rpm) is easier achievable than with other technology.

Brushless Motor

Three-phase synchronous motors are commutated servo motors, optimized for sinusoidal current. These brushless AC motors produce a constant and uniform torque, especially at lower speeds.

These low voltage motors have several advantages:

• Power density

• Positioning accuracy

• Energy efficiency

• Low noise and heat generation

The brushless motor can directly be integrated into a battery-powered system, making it suitable for mobile applications requiring highly dynamic acceleration, high efficiency and smooth and quiet running conditions for torque and speed control.

Conclusion

• Brushless motors are more efficient

• Offer better running and operating conditions

• Low wear

• Better control over positioning

• A higher degree of efficiency

For these reasons, almost all alkitronic tools are designed and produced with and operated by brushless low wearing motors to eliminate or minimize motor maintenance, increase the lifetime, reduce noise and heat emissions and optimize the operating and running smoothness for the users.