Cylindrical slotless rotor for small electromotor - has coil former with outer skin comprising axially-compressed ferromagnetic wire helix

摘要

The rotor consists of a cylindrical coil former (1) for an axially-compressed helical spring made of ferromagnetic wire. The helical sheath is wrapped around the outside of the main body of the former between its two end flanges. The flanges have posts (21) projecting axially-parallel outwards from the peripheries of the end faces. The rotor's shaft passes through the centre of the coil former. The rotor winding is looped axially-parallel over the surface of the helical sheath and around the flange posts.