Permanent magnet, collector-less external rotor motor, has rotor bell with surface that is opened outwards, and miniature bodies provided at preset position of surface, partially embedded in surface and formed as balls

摘要

The motor has an external rotor (20) separated from an inner stator by an air gap. A rotor magnet (26) and a rotor bell (28) are provided in the rotor. The rotor bell has a surface that is opened outwards. Miniature bodies (54) are provided at preset position of the surface and are partially embedded in the surface. The miniature bodies are formed as balls and are made of metallic material. The rotor bell is made of plastic. The bodies are arranged in two balancing planes (32, 34), which extend perpendicular to a rotational axis of the rotor.