DE202008016798U1 - Rotor for a magnetic bearing - Google Patents

Abstract

Permanent magnet assembly for a rotor for a magnetic bearing, wherein the permanent magnet arrangement one or more concentrically arranged annular permanent magnets (2), wherein the annular Permanent magnets (2) are formed from permanent magnet segments, and between two radially adjacent permanent magnet rings (2) a collector ring (3) is provided, characterized in that each segment of a permanent magnet ring (2) with at least one radially adjacent collector ring (3, 4, 5) is toothed by a peripheral surface of the segment, a projection / recess is provided, the / in a correspondingly shaped recess / projection engages, the / the opposite on the peripheral surface a radially adjacent collector ring (3, 4, 5) is provided.

Description

The The present invention relates to a rotor with improved permanent magnet arrangement for magnetic bearings, in particular high-temperature superconductor magnetic bearings with planar configuration.

As a general rule Magnetic bearing include a first bearing part, the rotor, with a Rotor shaft is firmly connected and in operation together with this rotates, and a second bearing part, referred to as a stator is and is static in operation, that is not agitated becomes.

For a high-temperature superconductor magnetic bearing contains the rotor an exciter system of juxtaposed permanent magnets, wherein between the permanent magnets, a ferromagnetic material for the concentration of the magnetic flux, also referred to as a collector, can be provided.

Of the Stator has a high temperature superconductor, for example Base of oxide ceramic materials such as Bi-Sr-Ca-Cu-O or Y-Ba-Cu-O. The high-temperature superconductor is in a thermal Insulating housing with cooling, such as a cryostat, around that required for the superconducting properties Cool the superconductor to a temperature below to ensure its critical temperature.

In planar magnetic bearings are the permanent magnets of the exciter system arranged annularly around the rotor shaft, fixed to this mounted, wherein the magnetic rotor is in the form of an annular disc having.

Of the Stator with high-temperature superconductor also has the shape of a annular disc, wherein the rotor shaft through the central Ring opening runs.

For a magnetic bearing with planar configuration are the stator and the Rotor axially spaced from each other on the rotor shaft, wherein a rotor disk is located between two stator disks.

The Permanent magnet arrangement comprises at least one, usually a plurality of concentrically arranged annular permanent magnets on. Between two adjacent permanent magnet rings can also annular ferromagnetic elements, hereinafter designated as collector rings, be provided.

Usually put the individual permanent magnet rings from a row composed of individual permanent magnet segments.

in the Operation arise due to the high speeds high centrifugal forces. In addition, acting on the system in addition to the high centrifugal forces the bearing forces of the bearing and possibly occurring Resonances. These forces can cause that the permanent magnet arrangement expands, the mating fits lost, the arrangement is released from the rotor shaft or the individual components shift to each other.

to Avoiding this problem it is known to the outside Circumference of the permanent magnet arrangement a reinforcing element made of a high-strength, non-magnetic material under tension, For example, from a glass fiber reinforced plastic (GFK) or carbon fiber reinforced plastic (CFRP).

Such a permanent magnet arrangement with a reinforcing element running around the outer circumference is shown in FIG WO 2005/019670 A1 described. The individual permanent magnet rings are separated at least one point and the individual segments of a ring spaced from each other to eliminate occurring in unseparated permanent magnets tagential supporting forces.

WO 2007/031751 A1 relates to a disc-shaped permanent magnet arrangement which is very thin. Due to the low thickness of the disc, this tends to sag. The problem of sagging is solved by providing a support disk of non-magnetic material on at least one end face of the disk.

Independently from the presence of an outer peripheral reinforcing element There is a risk that in operation the individual components move against each other, disassemble and out of the composite can be torn out.

It It was therefore an object of the present invention to provide a permanent magnet arrangement to provide, even at high loads in operation forms a solid composite in which the individual components remain stationary and to realize the simple way is.

According to the invention, this object is achieved by a permanent magnet arrangement for a rotor for a magnetic bearing, wherein the permanent magnet arrangement comprises one or more concentric annular permanent magnets, wherein the annular permanent magnets are formed from permanent magnet segments, and between two radially adjacent permanent magnet rings a collector ring is provided, each Segment of a permanent magnet ring with at least is meshed with a radially adjacent collector ring by a projection / depression is provided on at least one peripheral surface of the segment, and opposite to the peripheral surface of a radially adjacent collector ring a correspondingly shaped recess / projection is provided, and engage the projection and the corresponding recess.

According to the invention each segment of a permanent magnet ring with at least one radial toothed adjacent collector ring. Preferably, each segment both with the radially inner and radially outer toothed adjacent collector ring.

According to the invention as peripheral surface of a segment in the radial direction spaced from the axis of rotation inner or designated outer surface.

in the Case of an annular arrangement, these are the internal or outer circular arc of the relevant Segment.

For The present invention will become the inner peripheral surface as inner peripheral surface and the outer one Peripheral surface as outer peripheral surface designated.

below The present invention will be explained with reference to the attached figures.

It shows,

1 schematically a conventional magnet arrangement,

2 schematically the top view of an embodiment of a permanent magnet arrangement according to the invention and

3 schematically a cross section through a further embodiment of a permanent magnet arrangement according to the invention.

1 shows the conventional structure of a ring-shaped permanent magnet arrangement for a rotor disk 1 from here three concentric annular permanent magnets 2 , each formed of a series of individual permanent magnet segments, with collector rings 3 extending between two adjacent annular permanent magnets 2 and an outer collector ring 4 along the outer periphery of the outermost permanent magnet ring 2 the arrangement runs, and an inner collector ring 5 which runs along the inner peripheral surface of the innermost collector ring.

The central ring opening 5 used for mounting on the rotor. Usually, a reinforcing element is stretched around the outer circumference of the arrangement, which together hold the individual components of the arrangement in operation and should prevent a change in position (not shown here).

In 2 schematically an embodiment of the invention for a permanent magnet assembly is shown. The embodiment shown here consists of three concentric permanent magnet rings 2 , each composed of a series of individual permanent magnet segments. Each around the inner and outer peripheral surface of the individual permanent magnet rings 2 runs a collector ring 3 . 4 . 5 ,

According to the invention between the individual permanent magnet segments and the radially adjacent collector rings 3 . 4 . 5 provided at least one gearing.

The Gearing is done by putting a projection on a circumferential surface a first component (segment, collector ring) in a corresponding shaped opposite recess in the peripheral surface the radially adjacent second component (collector ring, segment) intervenes.

Except for the outermost and innermost ring of the assembly (here the outer collector ring 4 and inner collector's ring 5 ); the recesses / protrusions have only on the inner and outer peripheral surface, the projections / depressions can be on both the outer peripheral surface and on the inner peripheral surface of the permanent magnet segments and the collector rings 3 are located.

In the in 2 illustrated embodiment, each permanent magnet segment on each of the inner and outer peripheral surface on a recess. A correspondingly shaped opposing projection is located in the outer and inner adjacent collector ring for each permanent magnet segment 3 . 4 . 5 ,

The Shape of the projections and their counterparts, the Wells, is not subject to any special restrictions.

she may be trapezoidal, preferably with equally long legs, be rectangular, round, (saw) tooth-shaped, etc.

Also the form of the reason of the depression is not special Restrictions, however, should conform to the shape of the tab be adjusted. The reason may be flat, curved, pointed etc. be.

Depending on requirements, a plurality of projections / recesses or both projections and recesses may be provided on the peripheral surfaces of the segments, with corresponding counterparts in the peripheral surface of one or both radially adjacent collector rings 3 . 4 . 5 ,

Further can be one or more on a perimeter area Depressions and on the opposite circumferential surface a permanent magnet segment / collector ring one or more projections provided be.

One Projection and an associated opposite Deepening can be done by the tongue and groove principle extend the entire strength of the respective ring / segment. Similarly, the recesses / projections around the entire circumference of the permanent magnet rings and the collector rings run.

A cross section through an inventive arrangement shows 3 , Here are the collector rings 3 on their opposite peripheral surfaces each have a rectangular projection which engages in a correspondingly shaped rectangular recess, each opposite in the peripheral surface of the radially adjacent permanent magnet segment 2 is provided.

The radially furthest from the axis of rotation 9 spaced collector ring 4 is only on the inner peripheral surface and the radially closest to the axis of rotation 9 lying inner collector ring 5 provided on its outer peripheral surface with corresponding rectangular projections. Along the outer periphery of the assembly is a reinforcement 6 for example from CFK etc.

Also indicated is a mounting part 8th for mounting the permanent magnet assembly to the rotor and the axis of rotation 9 ,

By inventively provided toothing of the permanent magnet segments of a ring 2 with at least one radially adjacent collector ring 3 . 4 . 5 a very stable composite is obtained, which can withstand very high forces occurring in operation, without the individual components of the arrangement move against each other, diverge or the composite dissolves.

1

Permanent magnet assembly

2

annular Permanent magnet, composed of individual permanent magnet segments

3

collector ring

4

outer collector ring

5

internal collector ring

6

central ring opening

7

reinforcement

8th

mounting part

9

axis of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 2005/019670 A1 [0012]
• WO 2007/031751 A1 [0013]

Claims (10)

Permanent magnet arrangement for a rotor for a magnetic bearing, wherein the permanent magnet arrangement comprises one or more concentrically arranged annular permanent magnets ( 2 ), wherein the annular permanent magnets ( 2 ) are formed from permanent magnet segments, and between two radially adjacent permanent magnet rings ( 2 ) a collector ring ( 3 ), characterized in that each segment of a permanent magnet ring ( 2 ) with at least one radially adjacent collector ring ( 3 . 4 . 5 ) is provided by a protrusion / recess is provided on a peripheral surface of the segment, which engages in a correspondingly shaped recess / projection, the / on the opposite circumferential surface of a radially adjacent collector ring ( 3 . 4 . 5 ) is provided. Permanent magnet arrangement according to claim 1, characterized in that each segment is connected to both the radially inwardly and radially outwardly adjacent collector ring (11). 3 . 4 . 5 ) is toothed. Permanent magnet arrangement according to claim 1 or 2, characterized in that for the toothing in the outer and inner peripheral surface of a segment at least one recess is provided, in which engages a correspondingly shaped projection, which is opposite in a radially adjacent collector ring ( 3 . 4 . 5 ) is provided. Permanent magnet arrangement according to one of the preceding claims, characterized in that the recess or the projection over the entire thickness of the corresponding segment or collector ring ( 3 . 4 . 5 ). Permanent magnet arrangement according to one of claims 2 to 3, characterized in that the recess or the projection around the entire circumference of a permanent magnet ring ( 2 ) or a collector ring ( 3 . 4 . 5 ) runs. Permanent magnet arrangement according to one of the preceding claims, characterized in that on a peripheral surface of a segment or collector ring ( 3 ) A depression is provided and on the other peripheral surface a projection. Permanent magnet arrangement according to one of claims 1 to 6, characterized in that on the outer peripheral surface of the radially farthest from the axis of rotation ( 8th ) spaced permanent magnet ring ( 2 ) or collector rings ( 4 ) a reinforcing element ( 7 ) which extends around the outer circumference. Permanent magnet arrangement according to claim 7, characterized characterized in that the reinforcing element consists of a Material is selected, which is selected under a glass fiber reinforced Plastic or carbon fiber reinforced plastic. High temperature superconductor magnetic bearing with planar Configuration, characterized in that the bearing is a rotor comprising a permanent magnet arrangement according to one of the claims 1 to 8. High-temperature superconductor magnetic bearing according to claim 9, characterized in that the high-temperature superconductor selected is under a high temperature superconducting material based on Bi-Sr-Ca-Cu-O and Y-Ba-Cu-O.