An electric motor comprising a rotor and a stator is disclosed. The rotor is supported on a substantially spherical bearing and is of a substantially spherical design facing the stator, which has a high degree of efficiency. The stator may have a magnetic return-path body which is made of a compressed powder material. The return-path body may be of a substantially spherical design, at least in segments facing the rotor.
1. An electric motor comprising:
a rotor; and
a stator;
wherein the rotor is supported on a substantially spherical bearing and is of a substantially spherical design facing the stator;
wherein the stator has a magnetic return-path body made of a compressed powder material; and
wherein the return-path body comprises a plurality of segments each having a substantially spherical surface facing the stator; and
wherein the return-path body has coil receiving portions which are arranged under the spherical surface areas facing the stator.
2. The electric motor according to claim 1 , wherein:
the return-path body is a compact body or comprises compact return-path body elements.
3. The electric motor according to claim 1 , wherein:
the return-path body is composed of a plurality of return-path body elements.
4. The electric motor according to claim 3 , wherein:
adjacent return-path body elements are connected via a plug connection.
5. The electric motor according to claim 1 , wherein:
adjacent segments are magnetically separated.
6. The electric motor according to claim 1 , wherein:
a gap is provided between adjacent segments.
7. The electric motor according to claim 1 , wherein:
segments are connected to one another via a return-path area.
8. The electric motor according to claim 1 , wherein:
the return-path body surrounds the rotor in a ring shape.
9. The electric motor according to claim 1 , wherein:
the powder material comprises iron granules electrically insulated relative to one another.
10. The electric motor according to claim 1 , wherein:
the coil receiving portion is provided with an electric insulation and/or an accommodated coil is provided with an electric insulation towards the coil receiving portion.
11. The electric motor according to claim 1 , wherein:
the coil receiving portions are arranged and designed such that accommodated coils do not project beyond the spherical area of the return-path body in the direction of the rotor.
12. The electric motor according to claim 1 , wherein:
an air gap formed between the rotor and a spherical area of the return-path body is free from coils.
13. The electric motor according to claim 1 , wherein:
the return-path body has a plurality of recesses as coil receiving portions or for the formation of coil receiving portions.
14. The electric motor according to claim 13 , wherein:
a recess having an area facing the rotor is set back in relation to the spherical surface of the return-path body.
15. The electric motor according to claim 1 , wherein:
a coil is wound onto a coil receiving portion.
16. The electric motor according to claim 1 , wherein:
a prefabricated coil is positioned onto a coil receiving portion.
17. The electric motor according to claim 1 , wherein:
a coil receiving portion is dimensioned such that the part of the return-path body located in the area of the generated magnetic field of the accommodated coil is considerably smaller than the area of the return-path body transferring the generated magnetic field towards the rotor.
18. The electric motor according to claim 1 , wherein:
a coil receiving portion is dimensioned such that an adequate area of the return-path body is made available in order to transport magnetic flux below the saturation level.
19. The electric motor according to claim 1 , wherein:
a coil receiving portion is designed such that a coil with a round or approximately round cross section is adapted to be accommodated.
20. The electric motor according to claim 1 , wherein:
the coil receiving portions are arranged behind or beneath the spherical surface area of the return-path body facing the rotor.
21. The electric motor according to claim 20 , wherein:
the return-path body has a connecting area located transversely to an axis of rotation of the rotor and making a transverse magnetic connection available.
22. The electric motor according to claim 21 , wherein:
the coil receiving portions are formed at the connecting area.
23. The electric motor according to claim 1 , wherein:
the rotor is a cage rotor.
24. The electric motor according to claim 1 , wherein:
the rotor is adapted to generate a magnetic field.
25. The electric motor according to claim 24 , wherein:
the rotor comprises a plurality of permanent magnets.
26. The electric motor according to claim 1 , wherein:
the rotor is a hysteresis rotor.