A three phase DC motor (10) including a rotor portion (12) and a stator portion (16). The rotor portion (12) includes 6N.+-.2 permanent magnet poles (32), and the stator portion(16) includes 6N electromagnet poles where N in an integer. The motor (10) is characterized in that it has a high pole density,...http://www.google.fr/patents/US5164622?utm_source=gb-gplus-shareBrevet US5164622 - High pole density three phase motor
