... 4. Bush bearing, 5. Pump shaft, 6. Inner magnet rotor, 7. External magnet rotor, 8. Bracket, 9.-11. Coupling, 12.Hood, 13. ... 4.Bush bearing, 5. Pump shaft, 6. Inner magnet rotor, 7. External magnet rotor. 8. Bracket, 9. Electric motor, 10. Base.Operating principle ... and pulling force between the external magnet rotor and inner magnet rotor, electric motor can drive the inner rotor, pump’s shaft and ...