A first layer coil is wound around the surface of a tooth in a direction advancing from a proximal end portion to a distal end portion of this tooth. A second layer coil is wound on the first layer coil in a direction advancing from the distal end portion to the proximal end portion of the tooth coil....http://www.google.fr/patents/US7148593?utm_source=gb-gplus-shareBrevet US7148593 - Concentrated winding stator coil for an electric rotary machine
Concentrated winding stator coil for an electric rotary machine
