Permanent magnet ring motors are a type of brushless motor used across a wide range of industrial automation applications. These types of motor solutions are known for their high-speed, vibration-free operation that allows for precision in power output.
Why should you use ring motors for your automation solution? Which applications are they ideal for? Find out more about the unique features and primary applications of ring motors.
How Ring Motors Work
The general construction of a ring motor consists of a cylindrical rotor and stator. These types of motors feature a tubular form factor, radial flux rotor design, and a through hole with a large radius to the radial thickness of the motor rotor-stator components.
There are basic varieties of ring motors:
- In-runner: with a rotor inside the stator
- Out-runner: with a rotor outside the stator
- Dual-rotor: consisting of both inner and outer rotating components
All three of these designs have permanent magnets and are also paired with electromagnetic stators.
The difference between ring motors and their brushless DC (BLDC) motors counterparts lies in pole counts. Ring motors have higher pole counts due to the larger diameter of the rotors.
Why Are Ring Motors Used?
Ring motors have some key benefits that make them more ideal for certain applications over BLDC motors:
- Excellent mechanical design flexibility: ring motors have an open design platform that allows for customizable motor components and plenty of integration opportunities. Ring motors can also be modified to include a variety of accessories.
- The hollow center of the motor allows mechanical components to be located the motor.
- The high magnetic pole count of ring motors comes with weight savings without sacrificing power. Ring motors also have a high power and torque to weight ratio.
- High pole counts also increase motor controller communication frequency.
- Ring motors allow engineers to save space and reduce the number of components used.
Applications for Rings Motors
Ring motors make ideal choices for a variety of industrial automation applications:
- UAV manufacturing
- Pump manufacturing
- Optical scanning system manufacturing
- LIDAR, scanning, and beam steering systems
- Air bearings, optical actuators, grinding, and polishing systems
- Vacuum and space-rated applications (wafer processing and metrology equipment, satellite reaction wheels, etc.)