A newly developed laminated iron core is composed of number of unit segments, each of which is shaped such that one radial marginal periphery defines a half of a coil slot and the opposite periphery defines a half of a tooth between the two coil slots. Accordingly, when such segments are juxtaposed to form a layer of an annular iron core, a pair of the segments constitute a sector having an odd number (2n + 1) of coil slots, wherein n is the number of coil slots in a unit segment, whereas a pair of unit segments of ordinary type bears an even number of coil slots. Assembled iron cores each using either one of the type mentioned above bear a different number of coil slots suitable for different frequencies such as 50 Hertz and 60 Hertz but has the same outside and inside diameter and the same number of dovetail notches, thereby permitting two kinds of iron cores to be supported within a stator frame of single unified type.

Dynamoelectric machine rim construction with offset ring segments

Laminated iron core of rotary electric machines

A larger number of keys (L) are formed in the outer cylindrical surface of a rotor rim than is strictly necessary for fixing pole pieces (P) thereto. The keys are regularly spaced around the rim. This arrangement makes it possible to avoid having adjacent rim segments offset to each other by an angle which is equal to the pole pitch or at best to the half pole pitch as has previously been the case. The overlap between segments may now be at the pitch of the fixing keys. This can be used to increase the overlap factor, thereby increasing the mechanical strength of the rim against centrifugal forces.

Electric machine rotor having a laminated and segmented rim

The rotor of the radial bearing comprises a central shaft and a stack of ferromagnetic laminations constituted by a set of very thin individual laminations each of which extends over a limited angular sector around the periphery of the central shaft, said laminations being disposed in parallel planes so as to constitute a succession of flat split rings extending perpendicularly to the rotor axis. The individual laminations in any given plane are angularly offset relative to the individual laminations of the adjacent planes in such a manner as to provide a stack of laminations which is staggered. A bearing in accordance with the invention is suitable for supporting large diameter shafts which rotate at high speeds.

Large diameter radial magnetic bearing

A rotor, for a synchronous salient-pole electrical machine, having a rim built up in annular layers consisting of segments provided with recesses forming slots on the rim circumference, in which like poles are mounted and which form a plurality of groups distributed in series over the rim circumference, the distances between the adjacent slots in all the groups being the same and different than equal distances between the adjacent slots of different groups. In some of the segments the adjacent recesses are spaced from each other by a distance equal to the distance between the slots within a group. In other segments, mounted in those layers of the rim wherein, between the places of location of the adjacent slots of different groups there are no joints between the segments, the adjacent recesses are arranged in the same manner except that two adjacent recesses in each of the segments are located at a distance equal to the distance between the adjacent slots of different groups and coincident, upon the installation, with the places of location of these slots.

Laminated rotor for a synchronous salient-pole electrical machine

not available for EP0090324Abstract of corresponding document: US4489249A larger number of keys (L) are formed in the outer cylindrical surface of a rotor rim than is strictly necessary for fixing pole pieces (P) thereto. The keys are regularly spaced around the rim. This arrangement makes it possible to avoid having adjacent rim segments offset to each other by an angle which is equal to the pole pitch or at best to the half pole pitch as has previously been the case. The overlap between segments may now be at the pitch of the fixing keys. This can be used to increase the overlap factor, thereby increasing the mechanical strength of the rim against centrifugal forces.

Dynamoelectric machine rim construction with offset ring segments

Citations

Laminated iron core of rotary electric machines

Electric machine rotor having a laminated and segmented rim

Large diameter radial magnetic bearing

Laminated rotor for a synchronous salient-pole electrical machine

Rotor with a laminated segmented rim and mounted poles for electric machines.

References

Laminated yokes in rotary electric machines

Rotor rims for electrical machines