Centrifuge with a magnetically stabilized rotor for centrifugal goods

• US 20020074882A1
• Filed: 07/12/2001
• Published: 06/20/2002
• Est. Priority Date: 07/13/2000
• Status: Active Grant

• Current Assignee: Adelwitz Technologiezentrum GmbH, Kendro Laboratory Products GmbH (Thermo Fisher Scientific Incorporated)
• Original Assignee: Adelwitz Technologiezentrum GmbH, Kendro Laboratory Products GmbH (Thermo Fisher Scientific Incorporated)
• Inventors: Jaekel, Ingo, Flogel-Delor, Uta, Werfel, Frank, Betke, Viktor, Kopp, Dietmar
• Granted Patent: US 6,806,604 B2
• Time in Patent Office: Days
• US Class Current: 310/90.5
• CPC Class Codes: B04B 9/12 Suspending rotary bowls ; Bearings; Packings for bearings
• CPC Class Codes: F16C 2202/34 Superconductivity
• CPC Class Codes: F16C 27/00 Elastic or yielding bearings or bearing supports, for exclusively rotary movement shock-damping bearings for watches or clocks G04B31/02
• CPC Class Codes: F16C 32/0438 with a superconducting body, e.g. a body made of high temperature superconducting material such as YBaCuO
• CPC Class Codes: F16C 32/0444 Details of devices to control the actuation of the electromagnets
• CPC Class Codes: F16C 37/005 of magnetic bearings
• CPC Class Codes: F16C 39/02 using mechanical means
• CPC Class Codes: G01M 17/007 Wheeled or endless-tracked vehicles G01M17/08 takes precedence

Abstract

A centrifuge with a rotor set-up having at least one magnetic bearing is invented to operate a novel centrifuge. The rotor arrangement is connected with at least one permanent magnet configuration which is radially separated by small gap from a passive superconducting magnet stator. the permanent magnets which are adjusted in such a way that the escaping magnetic flux penetrates the adjacent surface of the passive superconducting magnet stator at a substantially perpendicular orientation. A driving motor unit, preferably in the form of a contactless induction engine, ensures a free and frictionless rotation. The passive superconducting magnet stator is comprised a melt textured superconducting YBCO material of high critical current density which can be cooled below its critical temperature of T=92 K using an integrated cryogenic unit to obtain the superconducting state. The stator has a preferred shape of a cylinder or hollow cylinder.

Claims

1. A centrifuge comprising:

a rotor assembly rotatable about a rotor axis, the rotor assembly being configured to hold materials for separation;

a first superconducting magnetic bearing comprising;

a first permanent magnet configuration coupled with the rotor assembly so as to rotate concurrently with the rotor assembly; and

a passive first superconducting magnet stator being spaced apart from the first permanent magnetic configuration and the rotor assembly, the first superconducting magnet stator and first permanent magnet configuration being sufficiently close together to produce a magnetic field interaction therebetween; and

a motor coupled with the rotor assembly for selectively rotating the rotor assembly.

2. A centrifuge according to claim 1, wherein magnet field lines of the first permanent magnet configuration penetrate approximately perpendicular into at least one surface of the first superconducting magnet stator.

3. A centrifuge according to claim 1, wherein the position of rotor axis includes an angel from 0 to 90 degrees relative to a horizontal plane.

4. A centrifuge according to claim 1, wherein the first permanent magnet configuration comprises at least one permanent magnet ring or a permanent magnet cylinder, the first superconducting magnet stator being at least partially disposed in radial alignment with the first permanent magnet configuration.

5. A centrifuge according to claim 4, wherein the first superconducting magnet stator at least partially surrounds the first permanent magnet configuration.

6. A centrifuge according to claim 4, wherein the first permanent magnet configuration at least partially surrounds the first superconducting magnet stator.

7. A centrifuge according to claim 1, wherein:

the rotor assembly comprises a rotor mounted on a drive shaft; and

the first permanent magnet configuration comprises a plurality of discrete permanent magnets, each permanent magnet being disposed at a discrete location along the length of the drive shaft, the first superconducting magnet stator encircling the drive shaft.

8. A centrifuge according to claim 1, wherein:

the rotor assembly comprises a rotor having a substantially cylindrical housing projecting therefrom, the cylindrical housing having an inside face and an outside face; and

the first permanent magnet configuration comprises a plurality of discrete permanent magnets, each permanent magnet being disposed at a discrete location on the inside face of the cylindrical housing along the length thereof, at least a portion of the first superconducting magnet stator begin disposed within the cylindrical housing.

9. A centrifuge accordingly to claim 1, wherein the first permanent magnet configuration comprises:

a plurality of discrete permanent magnets; and

a collector ring disc disposed between each of the permanent magnets.

10. A centrifuge according to claim 1, wherein first permanent magnet configuration comprises a first permanent magnet concentrically disposed within a second permanent magnet r

11. A centrifuge according to claim 1, wherein the first superconducting magnet stator is connected to a cryogenic unit configured to cool the first superconducting magnet stator.

12. A centrifuge according to claim 11, wherein the first superconducting magnet stator is coupled directly to an in-housing integrated cryogenic unit to cool down the first superconducting magnet stator to below the critical temperature and to maintain the superconducting state.

13. A centrifuge according to claim 11, wherein the first superconducting magnet stator has a substantially solid or hollow cylindrical configuration.

14. A centrifuge according claim 13, wherein first superconducting magnet stator is comprised of a melt textured YBCO superconducting material of the composition Y_13-17Ba₂Cu₃O_7-δ

, wherein the material below T=92 K becomes superconducting.

15. A centrifuge according to claim 1, wherein first superconducting magnet stator comprises a melt textured multi-grain material of high mechanical stability configured to produce damping properties of the magnetic bearing.

16. A centrifuge according to claim 15, wherein the first superconducting magnet stator comprises a ring-shaped damping discs made from copper, aluminum or their basic alloys.

17. A centrifuge according to claim 1, further comprising:

a passive second superconducting magnet stator; and

a damping disc interposed between the first and second superconducting magnet stator, the damping disc being formed from copper, aluminum or their basic alloys.

18. A centrifuge according to claim 1, wherein the first superconducting magnet stator has the geometry of a ring or hollow cylinder.

19. A centrifuge according to claim 1, wherein first permanent magnet configuration comprises at least one permanent magnet a substantially ring or cylinder like configuration, the permanent magnet being mounted coaxially about the rotor axis.

20. A centrifuge according to claim 1, wherein the first permanent magnet configuration comprises a plurality of axial magnetized rings stacked axially with adjacent equal polarities and comprising a high radial magnetic flux density.

21. A centrifuge according to claim 1, wherein the first permanent magnet configuration comprises at least two annular permanent magnets mounted concentrically one in another in a plane whereby the rings are radially adjacent fitted.

22. A centrifuge according to claim 21, wherein in the radial direction the upper surfaces of neighboring rings show equal or alternating axial magnetization.

23. A centrifuge according to claim 1, wherein the first permanent magnet configuration comprises an integrated lower part of the rotor cup.

24. A centrifuge according to claim 1, wherein the first permanent magnet configuration comprises a single ring or cylinder like permanent magnet.

25. A centrifuge according to claim 1, further comprising:

a second superconducting magnetic bearing spaced apart from the first superconducting magnetic bearing, the second superconducting magnetic bearing comprising;

a second permanent magnet configuration coupled with the rotor assembly so as to rotate concurrently with the rotor assembly; and

a passive second superconducting magnet stator being spaced apart from the second permanent magnetic configuration and the rotor assembly, the second superconducting magnet stator and first permanent magnet configuration being sufficiently close together to produce a magnetic field therebetween.

26. Centrifuge with a rotor unit to process and separate different dense materials has least one bearing and is combined with a driving device rotatable around the rotor axis, wherein at least one part of the rotor unit is influenced by magnetic forces and is characterized in that the rotor arrangement (1) comprises at least one permanent magnet configuration (6, 7, 8, 9, 11, 12, 13, 14;

6′

, 11′

, 35) which interacts at given small distance with at least one adjacent superconducting magnet stator (19, 20;

19′

, 20′

;

36) wherein the permanent magnet configuration and the magnet stator comprise at least one passive superconducting magnetic bearing.