Permanent magnet rotor arrangement incorporating profiled tubes for permanent magnets

1. A permanent magnet rotor arrangement, comprising:

a rotor;

a plurality of nonmagnetic, axially extending profiled tubes defining a closed channel and affixed circumferentially along the outer rim of the rotor;

a plurality of permanent magnet pole pieces arranged in the channels,

wherein only one pole piece is arranged in each channel, wherein said only one piece is completely encapsulated by a respective nonmagnetic profiled tube, and

wherein the cross-sectional profile of the pole piece along a radial plane initially does not correspond to the cross-sectional profile of the channel along the radial plane,

wherein spaces are initially produced in each channel, between a surface of each pole piece and an inner surface of each tube,

wherein each of the plurality of nonmagnetic profiled tubes is compressed by an external compressing means or a vacuum is applied to each of the plurality of nonmagnetic profiled tubes to match the cross-sectional profile of the channel to the cross-sectional profile of the pole piece, such that their cross-sectional profiles are finally substantially equal.

2. The permanent magnet rotor arrangement according to claim 1 , wherein the tubes are monolithic.

3. The permanent magnet rotor arrangement according to claim 1 , wherein a filler substance is arranged in spaces between the pole piece and the inner surface of the tube.

4. The permanent magnet rotor arrangement according to claim 3 , wherein the filler substance is a resin.

5. The permanent magnet rotor arrangement according to claim 1 , wherein the tubes are affixed to the rotor by a dovetail joint.

6. The permanent magnet rotor arrangement according to claim 5 , wherein at least one protrusion of the tubes engages at least one corresponding groove of the rotor.

7. The permanent magnet rotor arrangement according to claim 1 , wherein the tubes are affixed to the rotor by one of: welding, spot welding, bolting and adhering.

8. The permanent magnet rotor arrangement according to claim 1 , wherein the tubes are affixed onto at least one magnet carrier being affixed to the rotor.

9. The permanent magnet rotor arrangement according to claim 1 , wherein the pole pieces are affixed on and/or supported by a magnet carrier, wherein the magnet carrier and the pole piece are enclosed in the channel.

10. The permanent magnet rotor arrangement according to claim 1 , wherein the tubes are made of PVC or stainless steel.