Electromagnetic rotary drive and a rotational device

Patent metadata

Field	Value
Publication number	US-11070108-B2
Application number	US-201916455175-A
Country	US
Kind code	B2
Filing date	Jun 27, 2019
Priority date	Jul 12, 2018
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

An electromagnetic rotary drive includes a ring-shaped magnetically effective core arranged around a stator and has a magnetic central plane. The stator is a bearing and a drive stator, with which, the rotor is contactlessly magnetically drivable about an axis of rotation, and with which the rotor is contactlessly magnetically levitatable with respect to the stator. The rotor actively magnetically levitated in a radial plane perpendicular to an axial direction, and passively magnetically stabilized in the axial direction and against tilting. The rotor includes a magnetically effective bearing ring arranged radially externally disposed and spaced from the magnetically effective core, and a bearing stator having a magnetically effective stator ring interacts with the bearing ring. The bearing stator is configured such that the stator ring passively magnetically stabilizes the rotor against tilting, and the bearing ring is connected to the magnetically effective core of the rotor via a connecting element.

First claim

What is claimed:

1. An electromagnetic rotary drive, which is designed as an external rotor, having a rotor comprising:
a ring-shaped magnetically effective core arranged around a stator and having a magnetic central plane, the stator being a bearing and a drive stator with drive coils, with which, in an operating state, the rotor being contactlessly magnetically drivable about an axis of rotation defining an axial direction, and with which the rotor is contactlessly magnetically levitatable with respect to the stator, the rotor actively magnetically levitated in a radial plane perpendicular to the axial direction, and passively magnetically stabilized in the axial direction and against tilting, the rotor comprising a magnetically effective bearing ring arranged radially externally disposed and spaced from the magnetically effective core of the rotor, and a bearing stator having a magnetically effective stator ring configured to interact with the bearing ring, the bearing stator configured and arranged such that the stator ring passively magnetically stabilizes the rotor against tilting with the drive coils disposed radially inwardly of both the magnetically effective core and the magnetically effective stator ring, and the bearing ring is connected to the magnetically effective core of the rotor via a connecting element made of a material configured to decouple the bearing ring and the magnetically effective core.

2. The rotary drive according to claim 1 , wherein the bearing ring of the rotor and the stator ring of the bearing stator each comprise at least one permanent magnet.

3. The rotary drive according to claim 1 , wherein the bearing ring of the rotor is arranged in the magnetic central plane of the magnetically effective core of the rotor.

4. The rotary drive according to claim 1 , wherein the bearing ring is arranged with respect to the axial direction at a distance different from zero to the magnetic central plane of the magnetically effective core of the rotor, and the distance is at most one quarter of the inner radius of the bearing ring.

5. The rotary drive according to claim 1 , wherein the stator ring of the bearing stator is arranged concentrically with the bearing ring of the rotor such that the stator ring surrounds the bearing ring radially externally disposed.

6. The rotary drive according to claim 1 , wherein the stator ring of the bearing stator is arranged spaced from the bearing ring of the rotor with respect to the axial direction, and the stator ring has a same inner radius as the bearing ring.

7. The rotary drive according to claim 1 , wherein the connecting element is disk-shaped.

8. The rotary drive according to claim 1 , wherein the connecting element comprises a plurality of spokes, each extending in a radial direction between the magnetically effective core of the rotor and the magnetically effective bearing ring of the rotor.

9. The rotary drive according to claim 1 , wherein the stator ring and the bearing ring each include a permanent magnetic material and are each segmented with a plurality of permanent magnets.

10. The rotary drive according to claim 2 , wherein the stator ring and the bearing ring each are magnetized in the axial direction, and a magnetization of the stator ring are directed in an opposite direction to a magnetization of the bearing ring.

11. The rotary drive according to claim 2 , wherein the stator ring and the bearing ring each are magnetized in a radial direction, a magnetization of the stator ring and a magnetization of the bearing ring being directed in a same direction.

12. The rotary drive according to claim 2 , wherein the stator ring is magnetized in the axial direction or the bearing ring is magnetized in a radial direction, or the stator ring is magnetized in a radial direction and the bearing ring is magnetized in the axial direction.

13. A rotational device for treating a surface of a disk-shaped body with which the body is rotatable for treatment, the rotational device comprising the electromagnetic rotary drive according to claim 1 , the rotor comprising a holder for the disk-shaped body.

14. A rotational device for conveying, mixing or stirring fluids, the rotational device comprising the electromagnetic rotary drive according to claim 1 , the rotor of the rotary drive being rotor of the rotational device.

15. The rotational device according to claim 14 , wherein the rotor has a plurality of vanes configured to mix or stir fluids, the vanes being arranged on the connecting element.

16. The rotary drive according to claim 4 , wherein the distance is at most one fifth of the inner radius of the bearing ring.

17. The rotary drive according to claim 1 , wherein the connecting element is disk-shaped and has a plurality of recesses.

18. The rotary drive according to claim 11 , wherein the magnetization of the stator ring and the magnetization of the bearing ring each are directed radially outwards.

19. The rotary drive according to claim 1 , wherein the rotor is disposed entirely externally to the drive coils of the stator.

Assignees

• Levitronix Gmbh

Inventors

• Nussbaumer Thomas
• Holenstein Thomas

Classifications

• H02K2201/15

  Sectional machines · CPC title

• H02K1/2786

  Outer rotors · CPC title

• H02K21/14

  with magnets rotating within the armatures · CPC title

• H02K1/28

  Means for mounting or fastening rotating magnetic parts on to, or to, the rotor structures · CPC title

• B01F33/4535

  using a stud for supporting the stirring element · CPC title