JPH0730793B2 - Magnetic bearing device - Google Patents
Magnetic bearing deviceInfo
- Publication number
- JPH0730793B2 JPH0730793B2 JP2050394A JP5039490A JPH0730793B2 JP H0730793 B2 JPH0730793 B2 JP H0730793B2 JP 2050394 A JP2050394 A JP 2050394A JP 5039490 A JP5039490 A JP 5039490A JP H0730793 B2 JPH0730793 B2 JP H0730793B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic bearing
- damping
- bearing device
- fixed portion
- case
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/044—Active magnetic bearings
- F16C32/0474—Active magnetic bearings for rotary movement
- F16C32/0476—Active magnetic bearings for rotary movement with active support of one degree of freedom, e.g. axial magnetic bearings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/0408—Passive magnetic bearings
- F16C32/041—Passive magnetic bearings with permanent magnets on one part attracting the other part
- F16C32/0417—Passive magnetic bearings with permanent magnets on one part attracting the other part for axial load mainly
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C32/00—Bearings not otherwise provided for
- F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
- F16C32/0406—Magnetic bearings
- F16C32/0408—Passive magnetic bearings
- F16C32/0423—Passive magnetic bearings with permanent magnets on both parts repelling each other
- F16C32/0425—Passive magnetic bearings with permanent magnets on both parts repelling each other for radial load mainly
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2360/00—Engines or pumps
- F16C2360/44—Centrifugal pumps
- F16C2360/45—Turbo-molecular pumps
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Magnetic Bearings And Hydrostatic Bearings (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は、磁気軸受装置に関し、特に、ラジアル方向
に対しては永久磁石のような受動型の磁気軸受を用い、
スラスト方向に対しては制御式の能動型の磁気軸受を用
いて、１軸制御のみを行なうような磁気軸受装置に関す
る。Description: TECHNICAL FIELD The present invention relates to a magnetic bearing device, and in particular, a passive magnetic bearing such as a permanent magnet is used in the radial direction.
The present invention relates to a magnetic bearing device in which only a single axis control is performed by using a control type active magnetic bearing in the thrust direction.
［従来の技術］ 最近では、製造コストを低減するために、外乱の少ない
用途への磁気軸受装置は、５軸制御よりも制御軸数の少
ない３軸制御,1軸制御が用いられようとしている。１軸
制御の場合、ラジアル方向には受動的な軸受が用いら
れ、軸方向のみが制御される。このような１軸制御型の
磁気軸受装置は、制御回路が最も簡単となり、実用化の
ための種々のくふうがなされている。ところが、１軸制
御型の磁気軸受装置は、残りの非制御の４軸の回りの減
衰がほとんど期待できないため、何らかの減衰を与えな
ければ、回転上昇あるいは下降時の固有振動通過時に大
きな振動を生じる。[Prior Art] Recently, in order to reduce the manufacturing cost, a magnetic bearing device for use with less disturbance is about to use 3-axis control or 1-axis control, which has a smaller number of control axes than 5-axis control. . In the case of one-axis control, a passive bearing is used in the radial direction and only the axial direction is controlled. In such a single-axis control type magnetic bearing device, the control circuit is the simplest and various types of practical applications have been made. However, since the one-axis control type magnetic bearing device can hardly expect damping around the remaining uncontrolled four axes, if some damping is not given, a large vibration occurs when the natural vibration passes when the rotation increases or decreases. .
このような、対策として、特公昭59−7731号公報および
特公昭62−37246号公報には、電気的なダンピング方法
を用いて減衰を与える技術が開示されており、その他に
機械式ダンパを用いた方法もある。As a countermeasure, Japanese Patent Publication No. 59-7731 and Japanese Patent Publication No. 62-37246 disclose a technique of providing damping by using an electric damping method. In addition, a mechanical damper is used. There is also a method.
［発明が解決しようとする課題］ しかしながら、上述の電気的なダンピング方法は固有振
動数と回転速度が一致していないときにのみ有効な減衰
を示すが、これらが一致したとき、つまり、固有振動通
過時は減衰力を生じないため、実用的でない。また、機
械的ダンパによる方法の場合には、独立した反発型のラ
ジアル磁気軸受を２個用いて、一方の反発型のラジアル
磁気軸受を弾性支持して、減衰機を追加する必要があ
り、構造が複雑になってしまうという欠点があった。[Problems to be Solved by the Invention] However, the above-described electrical damping method exhibits effective damping only when the natural frequency and the rotation speed do not match, but when these match, that is, the natural vibration It is not practical because it does not generate a damping force when passing. In the case of the mechanical damper method, it is necessary to use two independent repulsive radial magnetic bearings, elastically support one repulsive radial magnetic bearing, and add a damper. Has the drawback of being complicated.
それゆえに、この発明の主たる目的は、新たにダンパを
設けてラジアル方向の振動に対して減衰効果を高めた磁
気軸受装置を提供することである。Therefore, a main object of the present invention is to provide a magnetic bearing device in which a damper is newly provided to enhance the damping effect against the vibration in the radial direction.
［課題を解決するための手段］ この発明は永久磁石の反発力を利用したラジアル磁気軸
受と、軸方向磁気力を制御する制御式磁気軸受によって
回転軸を軸支し、軸方向吸引力によって生じるラジアル
剛性を利用した１軸制御型磁気軸受装置であって、制御
式磁気軸受の固定部を軸方向に剛に支持するための支持
部材と、制御式磁気軸受の固定部のラジアル方向を軟に
支持して低周波域での振動を減衰するめたの粘弾性減衰
部材と、固定部とケースとの間に挿入され、高周波域で
の振動を減衰させるための弾性体からなる摩擦ダンパと
を備えて構成したものである。[Means for Solving the Problems] The present invention has a radial magnetic bearing that utilizes the repulsive force of a permanent magnet and a controllable magnetic bearing that controls the axial magnetic force to rotatably support a rotating shaft, which is generated by an axial attractive force. A single-axis control type magnetic bearing device utilizing radial rigidity, wherein a support member for rigidly supporting the fixed part of the control type magnetic bearing in the axial direction and a radial direction of the fixed part of the control type magnetic bearing are softened. Equipped with a viscoelastic damping member that supports and dampens vibrations in the low frequency range, and a friction damper that is inserted between the fixed part and the case and is made of an elastic body for damping the vibrations in the high frequency range. It is configured by.
［作用］ この発明に係る磁気軸受装置は、支持部材によって制御
式磁気軸受の固定部を軸方向に剛に支持するとともに、
粘弾性減衰部材によってラジアル方向を軟に支持して低
周波域での振動を減衰し、さらに固定部とケースとの間
に摩擦ダンパを挿入して高周波域での振動を減衰したこ
とによって、ラジアル方向の振動に対して減衰効果を高
めることができる。[Operation] In the magnetic bearing device according to the present invention, the support member rigidly supports the fixed portion of the controllable magnetic bearing in the axial direction, and
The viscoelastic damping member softly supports the radial direction to damp vibrations in the low frequency range, and a friction damper is inserted between the fixed part and the case to damp vibrations in the high frequency range. The damping effect can be enhanced with respect to directional vibration.
［発明の実施例］ 第１図はこの第１図の一実施例の縦断面図であり、第２
図は第１図に示す線II−IIに添う横断面図であり、第３
図は第１図に示す線III−IIIに添う横断面図である。[Embodiment of the Invention] FIG. 1 is a longitudinal sectional view of an embodiment of FIG.
The drawing is a cross-sectional view taken along the line II-II shown in FIG.
The drawing is a cross-sectional view taken along the line III-III shown in FIG.
第１図ないし第３図を参照して、回転軸１はケース２内
で回転するものであって、その回転軸１の一端にはロー
タ３が取り付けられている。ロータ３の内面には永久磁
石４が設けられ、この永久磁石４に対向するケース２の
外面には永久磁石５が設けられる。これらの永久磁石４
と５とによって反発型磁気軸受６が構成される。なお、
回転軸１の一端に対向するケース２の内面には上部非常
用ベアリング７が取り付けられている。ケース２のほぼ
中央部には、回転軸１を回転させるためのモータステー
タ８が設けられる。Referring to FIGS. 1 to 3, a rotary shaft 1 rotates in a case 2, and a rotor 3 is attached to one end of the rotary shaft 1. A permanent magnet 4 is provided on the inner surface of the rotor 3, and a permanent magnet 5 is provided on the outer surface of the case 2 facing the permanent magnet 4. These permanent magnets 4
The repulsive magnetic bearing 6 is constituted by the elements 5 and 5. In addition,
An upper emergency bearing 7 is attached to the inner surface of the case 2 facing one end of the rotating shaft 1. A motor stator 8 for rotating the rotating shaft 1 is provided at a substantially central portion of the case 2.
モータステータ８の下部にはスラスト方向吸引用永久磁
石９が取り付けられた永久磁石ホルダ10が設けられてい
る。永久磁石ホルダ10に対向するようにスラスト板11が
回転軸１に設けられ、このスラスト板11の上部には、ス
ラスト方向吸引用永久磁石９に対向するように永久磁石
12が設けられている。スラスト板11の下部には電磁石13
が設けられ、この電磁石13はスペーサ14を介して前述の
永久磁石ホルダ10に取り付けられている。電磁石13は永
久磁石９と12との間に生じる軸方向への吸引力につりあ
うように、図示しない制御回路によって制御される。A permanent magnet holder 10 to which a thrust direction permanent magnet 9 is attached is provided below the motor stator 8. A thrust plate 11 is provided on the rotating shaft 1 so as to face the permanent magnet holder 10, and a permanent magnet is provided on the upper portion of the thrust plate 11 so as to face the permanent magnet 9 for attraction in the thrust direction.
Twelve are provided. At the bottom of the thrust plate 11 is an electromagnet 13
The electromagnet 13 is attached to the above-mentioned permanent magnet holder 10 via a spacer 14. The electromagnet 13 is controlled by a control circuit (not shown) so as to balance the attraction force in the axial direction generated between the permanent magnets 9 and 12.
電磁石13の回転軸１に向く内面には下部非常用ベアリン
グ15が設けられ、回転軸１の他端にはアキシャルセンサ
ターゲット16が設けられる。アキシャルセンサターゲッ
ト16に対向するように、軸方向の位置を検出するための
アキシャル方向位置センサ17がセンサ取付部材18によっ
て電磁石13の下面に固定される。永久磁石ホルダ10と電
磁石13とスペーサ14とアキシャル方向位置センサ17とか
らなるステータユニットは数本の鋼線19によってケース
２に取付けられる。その結果、ステータユニットは鋼線
19によって軸方向に剛く、ラジアル方向に柔らかく支持
されることになる。A lower emergency bearing 15 is provided on the inner surface of the electromagnet 13 facing the rotating shaft 1, and an axial sensor target 16 is provided on the other end of the rotating shaft 1. An axial position sensor 17 for detecting the axial position is fixed to the lower surface of the electromagnet 13 by a sensor mounting member 18 so as to face the axial sensor target 16. A stator unit including a permanent magnet holder 10, an electromagnet 13, a spacer 14 and an axial direction position sensor 17 is attached to the case 2 by several steel wires 19. As a result, the stator unit is made of steel wire.
It will be rigidly supported in the axial direction by 19 and softly supported in the radial direction.
ステータユニットとケース２との間の数箇所には第３図
に示すように軸方向にそって溝が形成されていて、そこ
にゴムなどの粘弾性減衰部材20が挿入されていて、ラジ
アル方向の振動に対して減衰がが与えられるとともに、
ステータユニットの回り止めの役割を果たしている。Grooves are formed along the axial direction at several places between the stator unit and the case 2 as shown in FIG. 3, and a viscoelastic damping member 20 such as rubber is inserted therein, and the grooves are arranged in the radial direction. Damping is given to the vibration of
It plays the role of a detent for the stator unit.
ところで、ターボ分子ポンプのような大きな慣性モーメ
ントを持つロータ３を高速回転させる場合、このジャイ
ロモーメントによって固有振動数が回転速度とともに変
化し、前回りと後回りの固有振動数が生じる。後回りの
固有振動数に対しては、前記ゴムなどの粘弾性体からな
る減衰部材20による減衰が可能である。しかし、この減
衰部材20では前回り固有振動数のような高い周波数に対
しての減衰性能が小さい。By the way, when the rotor 3 having a large moment of inertia such as a turbo molecular pump is rotated at a high speed, the natural frequency changes with the rotation speed due to the gyro moment, and the natural frequencies of the forward and backward directions are generated. The rear natural frequency can be damped by the damping member 20 made of a viscoelastic body such as rubber. However, this damping member 20 has a small damping performance for high frequencies such as the forward natural frequency.
そこで、この発明の一実施例では、第２図に示すような
摩擦ダンパ21がステータユニット８とケース２との間に
挿入される。第２図に示した摩擦ダンパ21は薄いばね用
板材を数枚重ねてステータユニットとケース２との間に
挿入されている。これにより、ステータユニットはラジ
アル方向に押し付けられている。このように摩擦ダンパ
21を設けることによって、ステータユニットの振動によ
りステータユニットおよび板ばね間あるいは板ばね間に
摩擦力が生じ、この摩擦力により振動エネルギーが吸収
され、ステータユニットの振動を押えることができる。Therefore, in one embodiment of the present invention, a friction damper 21 as shown in FIG. 2 is inserted between the stator unit 8 and the case 2. The friction damper 21 shown in FIG. 2 is inserted between the stator unit and the case 2 by stacking several thin spring plate members. As a result, the stator unit is pressed in the radial direction. Friction damper like this
By providing 21, a frictional force is generated between the stator unit and the leaf springs or between the leaf springs due to the vibration of the stator unit, the vibration energy is absorbed by the frictional force, and the vibration of the stator unit can be suppressed.
第４図はこの発明の他の実施例を示す要部断面図であ
る。この第４図に示した例は、ケース２の底面に板ばね
22を配置し、この板ばね22とステータユニットの間に摩
擦材23を挿入したものであり、摩擦材23と板ばね22は軸
方向に押し付けられている。ステータユニットのラジア
ル方向の振動はステータユニットと摩擦材23の摩擦力に
より減衰される。FIG. 4 is a cross-sectional view of essential parts showing another embodiment of the present invention. The example shown in FIG. 4 has a leaf spring on the bottom surface of the case 2.
22 is arranged and a friction material 23 is inserted between the leaf spring 22 and the stator unit. The friction material 23 and the leaf spring 22 are pressed in the axial direction. The radial vibration of the stator unit is damped by the frictional force between the stator unit and the friction material 23.
［発明の効果］ 以上のように、この発明によれば、ステータユニットか
らなる固定部を軸方向に剛に支持するとともに、ラジア
ル方向を軟に支持して低周波域での振動を減衰し、固定
部とケースとの間に粘弾性体からなる摩擦ダンパを挿入
して高周波域での振動を減衰させるようにしたので、ラ
ジアル方向の振動に対して減衰効果を高めることができ
る。[Effects of the Invention] As described above, according to the present invention, the fixed portion composed of the stator unit is rigidly supported in the axial direction, and the radial direction is softly supported to damp vibrations in the low frequency range. Since the friction damper made of a viscoelastic body is inserted between the fixed portion and the case to damp vibrations in the high frequency range, it is possible to enhance the damping effect against vibrations in the radial direction.
第１図はこの発明の一実施例の縦断面図である。第２図
は第１図に示す線II−IIに沿う横断面図である。第３図
は第１図に示す線III−IIIに沿う横断面図である。第４
図はこの発明の他の実施例の要部を示す縦断面図であ
る。 図において、１は回転軸、２はケース、３はロータ、4,
5,9,12は永久磁石、６は反発型磁気軸受、７は上部非常
用ベアリング、８はモータステータ、10は永久磁石ホル
ダ、11はスラスト板、13は電磁石、14はスペーサ、15は
下部非常用ベアリング、16はアキシャルセンサターゲッ
ト、17はアキシャル方向位置センサ、18はセンサ取付部
材、19は鋼線、20は粘弾性減衰部材、21,23は摩擦ダン
パ、22は板ばねを示す。FIG. 1 is a vertical sectional view of an embodiment of the present invention. FIG. 2 is a transverse sectional view taken along the line II-II shown in FIG. FIG. 3 is a cross-sectional view taken along the line III-III shown in FIG. Fourth
The drawing is a vertical cross-sectional view showing the main part of another embodiment of the present invention. In the figure, 1 is a rotary shaft, 2 is a case, 3 is a rotor, 4,
5, 9 and 12 are permanent magnets, 6 is a repulsive magnetic bearing, 7 is an upper emergency bearing, 8 is a motor stator, 10 is a permanent magnet holder, 11 is a thrust plate, 13 is an electromagnet, 14 is a spacer, and 15 is a lower part. An emergency bearing, 16 is an axial sensor target, 17 is an axial direction position sensor, 18 is a sensor mounting member, 19 is a steel wire, 20 is a viscoelastic damping member, 21 and 23 are friction dampers, and 22 is a leaf spring.
Claims (3)
軸受と、軸方向磁気力を制御する制御式磁気軸受によっ
て回転軸を軸支し、軸方向吸引力によって生じるラジア
ル剛性を利用した１軸制御型磁気軸受装置において、 前記制御式磁気軸受の固定部を軸方向に剛に支持するた
めの支持部材と、 前記制御式磁気軸受の固定部のラジアル方向を軟に支持
して低周波域での振動を減衰するための粘弾性減衰部材
と、 前記固定部とケースとの間に挿入され、高周波域での振
動を減衰させるための弾性体からなる摩擦ダンパとを備
え、 ラジアル方向の振動に対して減衰効果を高めたことを特
徴とする、磁気軸受装置。Claim: What is claimed is: 1. A radial magnetic bearing that utilizes the repulsive force of a permanent magnet, and a controllable magnetic bearing that controls the axial magnetic force to rotatably support a rotating shaft, and a single shaft that utilizes the radial rigidity generated by the axial attractive force. In a controlled magnetic bearing device, a supporting member for rigidly supporting the fixed portion of the controlled magnetic bearing in the axial direction, and a radial direction of the fixed portion of the controlled magnetic bearing is softly supported in a low frequency range. A viscoelastic damping member for damping the vibration of the, and a friction damper formed of an elastic body for damping the vibration in the high frequency region, which is inserted between the fixed portion and the case, On the other hand, a magnetic bearing device having a higher damping effect.
の間の複数の箇所に軸方向に挿入される、請求項第１項
記載の磁気軸受装置。2. The magnetic bearing device according to claim 1, wherein the friction damper is axially inserted at a plurality of positions between the fixed portion and the case.
記ケースの底面との間に挿入される、請求項第１項記載
の磁気軸受装置。3. The magnetic bearing device according to claim 1, wherein the friction damper is inserted between an end surface of the fixed portion and a bottom surface of the case.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2050394A JPH0730793B2 (en) | 1990-02-28 | 1990-02-28 | Magnetic bearing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2050394A JPH0730793B2 (en) | 1990-02-28 | 1990-02-28 | Magnetic bearing device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03255219A JPH03255219A (en) | 1991-11-14 |
| JPH0730793B2 true JPH0730793B2 (en) | 1995-04-10 |
Family
ID=12857658
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2050394A Expired - Fee Related JPH0730793B2 (en) | 1990-02-28 | 1990-02-28 | Magnetic bearing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0730793B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5226577B2 (en) * | 1974-01-24 | 1977-07-14 |
-
1990
- 1990-02-28 JP JP2050394A patent/JPH0730793B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03255219A (en) | 1991-11-14 |
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