Patent ID: 6455977
Filing Date: 2002-09-24
Classification: H02K

Abstract:
An electric machine with a rotor and a stator, the rotor being inserted into a central stator bore of the stator, andessentially axially running stator slots being arranged on an inner cylindrical surface of the stator, said cylindrical surface delimiting the stator bore; the stator slots being delimited in the circumferential direction by stator teeth; conductor bars of a stator winding being arranged in these stator slots in the circumferential direction between the stator teeth; the conductor bars of the stator winding consisting of a conductor material and of an insulation surrounding this conductor material, a radially inner boundary of the insulation defining a mechanical stator winding diameter (DM) and a radially inner boundary of the conductor material defining an effective stator winding diameter (Deff); the rotor containing a rotor barrel, said rotor barrel defining in its axial extent essentially the active part of the generator with magnetic fields which are high during operation; rotor retaining rings, the outside diameter of which is greater than that of the rotor barrel, being placed onto the rotor barrel at axial ends; the stator having in the active part a first zone (I) with a constant diameter (DI) of the stator bore, said diameter being greater than the diameter of the rotor barrel by double an air gap dimension (sI); the diameter (DI) of the stator bore in the first zone (I) being smaller than the effective stator winding diameter (Deff), such that the conductor material of the stator winding in the first zone (I) is overlapped at least completely in the circumferential direction by stator teeth; the stator having in the axial region of the rotor retaining ring a third zone (III) with a profile, at least approximately constant in the axial direction, of the diameter (DIII) of the stator bore, said diameter (DIII) being greater by a predetermined minimum amount (sIII) than the outside diameter of the rotor retaining ring, and said diameter (DIII) being greater than the diameter (DI) of the stator bore in the first zone (I); the stator having axially, between the first zone (I) and the third zone (III), a second zone (II) with a stator bore diameter (DII) increasing axially toward end faces of the stator; the diameter (DIII) of the stator bore in the third zone (III) being at no point appreciably greater than the effective stator winding diameter (Deff), such that the conductor material of the stator winding in the third zone (III) is overlapped, at least for a predominant part, in the circumferential direction by stator teeth and a distance (sIII) mechanically necessary between the stator in the third zone (III) and the rotor retaining ring is ensured.