Patent ID: 7750515

Claim:
A non-ventilated motor-generator for converting between electrical and rotary mechanical energy comprising: a rotor enclosed inside a metal motor-generator housing and supported on a bearing system to rotate about an axis of rotation; said rotor is constructed of two spaced apart rotor sections with circumferential arrays of permanent magnets that drive magnetic flux back and forth across an armature air gap; an air core armature located in said armature air gap comprising windings that are held together in a substantially non-magnetic structure that is structurally coupled to said motor housing; wherein, said armature air gap is a space between said permanent magnets and said armature winding; said air core armature having a thickness that is less than said armature air gap and said air core armature is located within said armature air gap such that two physical air gaps are created, with one on each side of said air core armature; one or more air flow passages through said rotor and around the inside surfaces of said motor-generator housing, and air flow inducers that induce flow of air in a polloidal loop through said passages and around said inside surfaces of said motor-generator housing when said rotor rotates; air flow in said polloidal loop includes a portion that passes through said armature air gap and a portion that is in contact with the inside of said motor-generator housing such that said air flow removes heat energy from said air core armature and transfers said heat energy to the inside of said motor-generator housing, wherein said heat energy is dissipated from said motor-generator housing.