Patent ID: 7525230
Filing Date: 2009-04-28
Classification: H02K

Abstract:
1. A brushless motor-generator for converting between electrical and mechanical energy comprising: a rotor that rotates about an axis of rotation, and a stator that is stationary and magnetically exerts torque upon said rotor, said rotor and said stator being radially separated and defining therebetween a radial air gap; said rotor having a ferromagnetic tube having an inner diameter, and a circumferential array of radially polarized magnetic poles of alternating polarity on said inner diameter of said ferromagnetic tube, wherein said magnetic poles drive magnet flux radially across said air gap; said stator including an air core armature that is located radially inside of said ferromagnetic tube and having multiple windings that are located in said magnetic air gap, and a nonmagnetic tube form onto which the windings are secured, said armature being positioned in said air gap so as to receive said magnetic flux such that AC voltage is induced in said windings as said rotor rotates; said windings having active lengths that traverse axially inside said magnetic air gap, and circumferential end turns linking said active lengths; said air core armature having a radially thin circumferentially tensioned band over wrapping the outer diameter of the axially traversing portions of said windings where located inside said magnetic air gap, wherein said tensioned band imparts radial compression and structural integrity to said windings.