JPH1182522A - Touchdown bearing for magnetic bearing device - Google Patents
Touchdown bearing for magnetic bearing deviceInfo
- Publication number
- JPH1182522A JPH1182522A JP9252307A JP25230797A JPH1182522A JP H1182522 A JPH1182522 A JP H1182522A JP 9252307 A JP9252307 A JP 9252307A JP 25230797 A JP25230797 A JP 25230797A JP H1182522 A JPH1182522 A JP H1182522A
- Authority
- JP
- Japan
- Prior art keywords
- balls
- touch
- bearing
- solid lubricant
- 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.)
- Withdrawn
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
- F16C39/00—Relieving load on bearings
- F16C39/02—Relieving load on bearings using mechanical means
-
- 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
- F16C32/0442—Active magnetic bearings with devices affected by abnormal, undesired or non-standard conditions such as shock-load, power outage, start-up or touchdown
-
- 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
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/38—Ball cages
- F16C33/3837—Massive or moulded cages having cage pockets surrounding the balls, e.g. machined window cages
- F16C33/3843—Massive or moulded cages having cage pockets surrounding the balls, e.g. machined window cages formed as one-piece cages, i.e. monoblock cages
-
- 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
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/38—Ball cages
- F16C33/44—Selection of substances
- F16C33/445—Coatings
-
- 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
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/66—Special parts or details in view of lubrication
- F16C33/6696—Special parts or details in view of lubrication with solids as lubricant, e.g. dry coatings, powder
-
- 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
- F16C19/00—Bearings with rolling contact, for exclusively rotary movement
- F16C19/54—Systems consisting of a plurality of bearings with rolling friction
- F16C19/541—Systems consisting of juxtaposed rolling bearings including at least one angular contact bearing
- F16C19/542—Systems consisting of juxtaposed rolling bearings including at least one angular contact bearing with two rolling bearings with angular contact
-
- 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)
- Rolling Contact Bearings (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、ターボ分子ポンプ
等の磁気軸受装置において、磁気軸受の制御不能時に回
転軸を支持するタッチダウン軸受に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch-down bearing for supporting a rotating shaft when a magnetic bearing cannot be controlled in a magnetic bearing device such as a turbo-molecular pump.
【０００２】[0002]
【従来の技術】図４に示すように、ターボ分子ポンプ等
の磁気軸受装置Ａは、縦型の回転軸１に対して隙間をも
って配設される複数の磁気軸受２と、回転軸１の上下両
端部に配設されるタッチダウン軸受３，４とを有する。
常時は、磁気軸受２が電磁的作用により回転軸１を非接
触支持するが、突然の断線や停電等によって突発的に磁
気軸受２が制御不能となった場合（いわゆるタッチダウ
ン時）には、上下一対のタッチダウン軸受３，４が、回
転軸１を支持して回転軸１および磁気軸受２の損傷を防
ぐように構成されている。2. Description of the Related Art As shown in FIG. 4, a magnetic bearing device A such as a turbo-molecular pump comprises a plurality of magnetic bearings 2 provided with a gap with respect to a vertical rotary shaft 1 and a vertical rotary shaft 1. Touch-down bearings 3 and 4 are provided at both ends.
Normally, the magnetic bearing 2 supports the rotating shaft 1 in a non-contact manner by electromagnetic action. However, when the magnetic bearing 2 suddenly becomes uncontrollable due to sudden disconnection or power failure (so-called touchdown), A pair of upper and lower touchdown bearings 3 and 4 are configured to support the rotating shaft 1 and prevent the rotating shaft 1 and the magnetic bearing 2 from being damaged.
【０００３】特に、下端部のタッチダウン軸受４は、図
５に示すように、２個のアンギュラ玉軸受１０，１１の
正面組合せとして、ラジアル荷重とアキシャル荷重の両
方を受けるようにしている。この各アンギュラ玉軸受１
０，１１は、内輪１２と、外輪１３と、複数のボール１
４と、リング状の保持器１５とを具備する。In particular, as shown in FIG. 5, a touch-down bearing 4 at a lower end portion receives both a radial load and an axial load as a front combination of two angular ball bearings 10 and 11. Each angular contact ball bearing 1
Reference numerals 0 and 11 denote an inner ring 12, an outer ring 13, and a plurality of balls 1
4 and a ring-shaped retainer 15.
【０００４】内輪１２は、外径面に軌道面１２ａが形成
され、上端面１２ｂと内径面１２ｃにタッチダウン面を
有している。外輪１３は、内径面に軌道面１３ａが形成
され、外径面がハウジング７に嵌合されている。ボール
１４は、内・外輪１２，１３の軌道面１２ａ，１３ａ間
に介装され自転・公転運動する。保持器１５は、ボール
１４を等間隔に保持するものである。The inner race 12 has a raceway surface 12a formed on an outer diameter surface, and has a touch-down surface on an upper end surface 12b and an inner diameter surface 12c. The outer race 13 has a raceway surface 13 a formed on the inner diameter surface, and the outer diameter surface is fitted to the housing 7. The ball 14 is interposed between the raceway surfaces 12a and 13a of the inner and outer races 12 and 13 and rotates and revolves. The retainer 15 holds the balls 14 at equal intervals.
【０００５】図６に示すように、各ボール１４は、保持
器１５に円周等間隔に複数設けられたポケット孔１６内
に収容される。また、ボール１４の円滑な転動を確保す
るため、ポケット孔１６のポケット面１６ａとボール１
４との間には、ポケット隙間ｓが設けられる。保持器１
５は、内径面１５ａが内輪１２と接触しつつ回転する。[0005] As shown in FIG. 6, each ball 14 is accommodated in a plurality of pocket holes 16 provided at equal intervals on a holder 15. Further, in order to ensure smooth rolling of the ball 14, the pocket surface 16a of the pocket hole 16 and the ball 1
4, a pocket gap s is provided. Cage 1
5 rotates while the inner diameter surface 15a is in contact with the inner ring 12.
【０００６】上記タッチダウン面（１２ｂ，１２ｃ）
は、磁気軸受２が正常に作動しているときは、回転軸１
との間に所定の隙間を有しているが、タッチダウン時
は、回転軸１と接触してこれを支持するものである。[0006] The touch-down surface (12b, 12c)
Indicates that when the magnetic bearing 2 is operating normally, the rotating shaft 1
And at the time of touchdown, it comes into contact with and supports the rotating shaft 1.
【０００７】上記構造のタッチダウン軸受４では、内輪
１２が回転軸１に対向し、その上端面および内径面がタ
ッチダウン面（１２ｂ，１２ｃ）になる。その反対に図
４においてハウジング７側を回転させ、中央の回転軸１
に設けた磁気軸受２によってハウジング７を支持する場
合には、タッチダウン軸受４の外輪１３が回転部材であ
るハウジング７に対向し、外輪１３の外径面でタッチダ
ウンすることになる。このようにタッチダウン面は軸受
の支持構造によりその位置が変わるものである。In the touch-down bearing 4 having the above-described structure, the inner ring 12 faces the rotary shaft 1, and the upper end surface and the inner diameter surface are the touch-down surfaces (12b, 12c). On the contrary, the housing 7 is rotated in FIG.
When the housing 7 is supported by the magnetic bearing 2 provided on the outer ring 13, the outer ring 13 of the touch-down bearing 4 faces the housing 7, which is a rotating member, and touches down on the outer diameter surface of the outer ring 13. As described above, the position of the touch-down surface changes depending on the bearing support structure.
【０００８】[0008]
【発明が解決しようとする課題】回転軸１が内輪１２の
タッチダウン面（１２ｂ，１２ｃ）と接触すると、内輪
１２が急激に回転し始め、これに追従してボール１４も
急激に自転・公転運動を開始する。このとき、非負荷域
に位置するボール１４と負荷域に位置するボール１４と
の間には公転の遅れ・進みがあり、この遅れ・進みによ
って保持器１５に大きな引張力或いは圧縮力が作用す
る。この繰り返し引張力・圧縮力により保持器１５に疲
労が生じるため、保持器１５の強度が問題となる。ま
た、軸受回転時、保持器１５のポケット面１６ａとボー
ル１４の表面，保持器１５の内径面１５と内輪１２の外
径面との間に滑り摩擦が生じるので、これらの表面の偏
摩耗が問題となる。When the rotating shaft 1 comes into contact with the touch-down surfaces (12b, 12c) of the inner race 12, the inner race 12 starts to rotate rapidly, and the ball 14 rapidly rotates and revolves accordingly. Start exercise. At this time, there is a delay or advance in the revolution between the ball 14 located in the non-load area and the ball 14 located in the load area, and a large tensile force or compressive force acts on the retainer 15 due to the delay or advance. . Since fatigue occurs in the cage 15 due to the repeated tensile and compression forces, the strength of the cage 15 becomes a problem. In addition, when the bearing rotates, sliding friction occurs between the pocket surface 16a of the cage 15 and the surface of the ball 14, and between the inner diameter surface 15 of the cage 15 and the outer diameter surface of the inner ring 12, so that uneven wear of these surfaces is reduced. It becomes a problem.
【０００９】特に、極低温環境で使用する場合は、保持
器１５を極低温で潤滑特性の良好なＰＴＦＥで形成する
場合が多いが、ＰＴＦＥでは必要な機械強度が得られな
い。In particular, when the cage 15 is used in a cryogenic environment, the cage 15 is often formed of PTFE having excellent lubricating properties at a cryogenic temperature, but PTFE cannot provide the required mechanical strength.
【００１０】そこで、本発明は、上記のようなタッチダ
ウン軸受における保持器の強度を確保すると共に、滑り
摩擦を生ずる表面の偏摩耗を防止することを目的とす
る。Accordingly, an object of the present invention is to secure the strength of the retainer in the above-described touch-down bearing and to prevent uneven wear of the surface that causes sliding friction.
【００１１】[0011]
【課題を解決するための手段】本発明のタッチダウン軸
受は、固定側に配設された磁気軸受により非接触状態で
支持される回転部材を、タッチダウン時に支持するタッ
チダウン軸受であって、内輪と、外輪と、前記内・外輪
間に転動自在に介装された複数のボールと、ボールを円
周所定間隔に保持する保持器とを有し、前記保持器が軟
鋼材、ステンレス鋼材、セラミックス材料等の機械強度
を有する材料からなり、保持器の滑り摩擦を生ずる表面
には固体潤滑剤被膜が形成されている。A touch-down bearing according to the present invention is a touch-down bearing for supporting a rotating member, which is supported in a non-contact state by a magnetic bearing disposed on a fixed side, at the time of touch-down, An inner ring, an outer ring, a plurality of balls rotatably interposed between the inner and outer rings, and a retainer for holding the balls at predetermined circumferential intervals, wherein the retainer is made of a mild steel material or a stainless steel material. The cage is made of a material having mechanical strength such as a ceramic material, and a solid lubricant film is formed on a surface of the cage where sliding friction occurs.
【００１２】ここで、保持器の「滑りを生ずる表面」と
は、ボール案内形式の保持器ではポケット面、軌道輪案
内形式の保持器ではポケット面及び案内面を意味する。
ただし、軌道輪案内形式の保持器では、ポケット面及び
案内面のうち少なくとも一方に固体潤滑剤被膜が形成さ
れていれば良い。Here, the "sliding surface" of the cage means a pocket surface in a ball guide type cage, and a pocket surface and a guide surface in a bearing ring guide type cage.
However, in the raceway guide type retainer, it is sufficient that at least one of the pocket surface and the guide surface is formed with a solid lubricant film.
【００１３】上記固体潤滑剤被膜の材料として、例えば
ＰＴＦＥ又は鉛が用いられる。また、上記固体潤滑剤被
膜の膜厚は、０．５μｍ〜２ｍｍであることが好まし
い。As a material for the solid lubricant film, for example, PTFE or lead is used. Further, the thickness of the solid lubricant film is preferably 0.5 μm to 2 mm.
【００１４】[0014]
【発明の実施の形態】本発明の一実施形態を図面に基づ
き説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.
【００１５】本発明に係るタッチダウン軸受は、図４に
示すような磁気軸受装置における回転軸１の上下両端部
に配設される。例えば、図１に示すように下端部のタッ
チダウン軸受６は、２個のアンギュラ玉軸受１９，２０
の正面組合せとして、ラジアル荷重とアキシャル荷重の
両方を受けるようにしている。また、上端部のタッチダ
ウン軸受も同様の構成である。The touch-down bearing according to the present invention is provided at both upper and lower ends of a rotating shaft 1 in a magnetic bearing device as shown in FIG. For example, as shown in FIG. 1, the touch-down bearing 6 at the lower end has two angular ball bearings 19, 20.
Are designed to receive both radial and axial loads. The touchdown bearing at the upper end has the same configuration.
【００１６】回転軸１の下端部には段部１ｂが形成さ
れ、この段部１ｂが上段のアンギュラ玉軸受１９の上端
面２１ｂとタッチダウン隙間ｕを介して対向し、また、
下端部の外周面１ｃが上下アンギュラ玉軸受１９，２０
の内輪２１，２６の内径面２１ｃ，２６ｃとタッチダウ
ン隙間ｕを介して対向している。内輪２１，２６の上端
面２１ｂ及び内径面２１ｃ，２６ｃには、タッチダウン
接触時の摩耗を防止するため、ＰＴＦＥ，二硫化モリブ
デン、鉛等による固体潤滑剤被膜が形成されている。A step 1b is formed at the lower end of the rotating shaft 1, and the step 1b faces the upper end surface 21b of the upper angular ball bearing 19 via a touch-down gap u.
Upper and lower angular contact ball bearings 19 and 20
And inner diameter surfaces 21c, 26c of the inner races 21, 26 with a touch-down gap u therebetween. A solid lubricant film made of PTFE, molybdenum disulfide, lead, or the like is formed on the upper end surface 21b and the inner diameter surfaces 21c, 26c of the inner rings 21, 26 in order to prevent abrasion during touchdown contact.
【００１７】アンギュラ玉軸受１９，２０の外輪２２，
２７はハウジング７の嵌合孔の内周面に嵌合され、さら
に下段の外輪２７の下面はハウジング７に固定された保
持リング８にて支持されている。The outer rings 22 of the angular contact ball bearings 19, 20
Reference numeral 27 is fitted to the inner peripheral surface of the fitting hole of the housing 7, and the lower surface of the lower outer ring 27 is supported by a holding ring 8 fixed to the housing 7.
【００１８】また、アンギュラ玉軸受１９，２０の各内
輪２１，２６の組合せ面には研削加工により隙間ｔが設
けられる。これにより、タッチダウン時の摩擦熱による
内輪２１，２６の軸線方向の熱膨張が許容され、軸受１
９，２０に過度の予圧がかからないよう構成されてい
る。A gap t is provided on the combined surface of the inner rings 21 and 26 of the angular ball bearings 19 and 20 by grinding. Accordingly, thermal expansion in the axial direction of the inner rings 21 and 26 due to frictional heat at the time of touchdown is allowed, and the bearing 1
It is configured such that an excessive preload is not applied to 9, 20.
【００１９】各アンギュラ玉軸受１９，２０の内輪２
１，２６と外輪２２，２７との間に複数のボール２３，
２８が介装され、保持器２４，２９によって円周等間隔
に保持される。Inner ring 2 of each angular ball bearing 19, 20
, 26 and the outer rings 22, 27, a plurality of balls 23,
28 are interposed and are held at equal circumferential intervals by retainers 24 and 29.
【００２０】ボール２３，２８は、内輪２１，２６の軌
道面２１ａ，２６ａと、外輪２２，２７の軌道面２２
ａ，２７ａとの間に所定の予圧荷重を与えられた状態で
介装され、保持器２４，２９のポケット孔２５，３０に
収容される。保持器２４，２９は内輪案内形式のもの
で、内輪２１，２６の外径面との間にわずかな案内隙間
を有する。The balls 23 and 28 are provided on the raceway surfaces 21a and 26a of the inner races 21 and 26 and the raceway surfaces 22 of the outer races 22 and 27, respectively.
a, 27a are interposed in a state where a predetermined preload is applied, and are accommodated in pocket holes 25, 30 of retainers 24, 29. The retainers 24 and 29 are of the inner ring guide type, and have a small guide gap between the retainers 24 and 29 and the outer diameter surfaces of the inner rings 21 and 26.
【００２１】保持器２４（保持器２９も同様の構成であ
る。）は、図２及び図３に示すように、リング状の部材
で、所要の機械強度を有する材料（例えば、軟鋼材、ス
テンレス鋼材、セラミックス材料等）で形成され、円周
等間隔に複数のポケット孔２５を有する。各ポケット孔
２５には、それぞれボール２３が収容される。各ポケッ
ト孔２５のポケット面２５ａとボール２３との間には、
ボール２３の円滑な転動を確保すべく所定のポケット隙
間ｓが設けられる。As shown in FIGS. 2 and 3, the retainer 24 (the retainer 29 has the same configuration) is a ring-shaped member having a required mechanical strength (eg, mild steel, stainless steel). And a plurality of pocket holes 25 at equal circumferential intervals. The ball 23 is accommodated in each pocket hole 25. Between the pocket surface 25a of each pocket hole 25 and the ball 23,
A predetermined pocket gap s is provided to ensure smooth rolling of the ball 23.
【００２２】軸受回転時、保持器２４は内径面２４ａを
内輪２１によって接触案内されながら回転し、ポケット
孔２５のポケット面２５ａでボール２３と接触する。When the bearing rotates, the retainer 24 rotates while being guided in contact with the inner diameter surface 24 a by the inner ring 21, and comes into contact with the ball 23 at the pocket surface 25 a of the pocket hole 25.
【００２３】保持器２４の滑り摩擦を生じる表面、この
実施形態では、ポケット面２５ａと案内面２４ａは、Ｐ
ＴＦＥ、鉛、或いは二硫化モリブデン等の固体潤滑剤で
被膜される。この固体潤滑剤被膜の膜厚は０．５μｍ〜
２ｍｍが好ましい。The surface of the retainer 24 that causes sliding friction, in this embodiment the pocket surface 25a and the guide surface 24a
Coated with a solid lubricant such as TFE, lead, or molybdenum disulfide. The thickness of the solid lubricant film is 0.5 μm or more.
2 mm is preferred.
【００２４】次に上記の如く構成されたタッチダウン軸
受６の作用について説明する。Next, the operation of the touchdown bearing 6 configured as described above will be described.
【００２５】電源系統の断線や停電等により磁気軸受の
機能が停止するタッチダウン時において、回転軸１がタ
ッチダウン軸受６の内輪２１，２６のタッチダウン面２
１ｂ，２１ｃ，２６ｃに接触すると、内輪２１，２６が
急激に回転し始める。同時に各ボール２３，２８は急激
に自転及び公転運動し始める。この際、各ボール２３，
２８には均等に負荷がかかっているのではなく、実際は
負荷域に位置するものと非負荷域に位置するものとがあ
って、これによりボール２３，２８の遅れ・進みが生じ
る。このボール２３，２８の遅れ・進みにより、保持器
２４，２９には引張力，圧縮力がかかり、これが保持器
２４，２９に疲労を生じさせる一因となる。しかしなが
ら、このタッチダウン軸受６は、保持器２４が軟鋼材、
ステンレス鋼材、セラミックス材料等の機械強度を有す
る材料で形成されており、上記の引張力・圧縮力に対し
て十分な強度があるため、疲労が生じにくく、その耐久
性が高いものとなる。At the time of touchdown in which the function of the magnetic bearing is stopped due to disconnection of the power supply system, power failure, or the like, the rotating shaft 1 is connected to the touchdown surface 2 of the inner rings 21 and 26 of the touchdown bearing 6.
When it comes into contact with 1b, 21c, 26c, the inner rings 21, 26 start to rotate rapidly. At the same time, each of the balls 23 and 28 suddenly starts rotating and revolving. At this time, each ball 23,
The load is not evenly applied to the balls 28, but there are actually ones located in the load region and ones located in the non-load region. This causes the balls 23 and 28 to delay and advance. Due to the delay / advance of the balls 23, 28, a tensile force and a compressive force are applied to the retainers 24, 29, which causes the retainers 24, 29 to become fatigued. However, in this touch-down bearing 6, the cage 24 is made of a mild steel material,
It is made of a material having mechanical strength such as a stainless steel material or a ceramic material, and has a sufficient strength against the above-mentioned tensile force and compressive force, so that fatigue is less likely to occur and its durability is high.
【００２６】また、保持器２４，２９のポケット面２５
ａおよび内径面２４ａに形成された固体潤滑剤被膜によ
って、滑り潤滑部分の潤滑が成される。さらに、ボール
２３，２８との接触、内輪２１，２６との接触によっ
て、ポケット面２５ａ及び内径面２４ａに形成された固
体潤滑剤被膜が、ボール２３，２８の表面、内輪２１，
２６の外径面、内・外輪の軌道面２１ａ，２２ａ，２６
ａ，２７ａに転着して転着被膜を形成する。これによ
り、保持器２４，２９のポケット面２５ａや内径面２４
ａの偏摩耗が防止され、保持器２４，２９の回転、或い
はボール２３，２８の自転・公転運動が円滑になされ
る。The pocket surfaces 25 of the retainers 24, 29
The lubrication of the sliding lubrication portion is achieved by the solid lubricant film formed on the inner surface 24a and the inner surface 24a. Further, the solid lubricant film formed on the pocket surface 25a and the inner diameter surface 24a due to the contact with the balls 23, 28 and the inner rings 21, 26 causes the surface of the balls 23, 28, the inner ring 21,
26, the outer and inner raceway surfaces 21a, 22a, 26
a and 27a to form a transfer film. As a result, the pocket surfaces 25a and the inner diameter surfaces 24 of the cages 24 and 29 are formed.
The uneven wear of “a” is prevented, and the rotation of the cages 24 and 29 or the rotation and revolution of the balls 23 and 28 are smoothly performed.
【００２７】特に、極低温環境で用いられる場合は、固
体潤滑剤としてＰＴＦＥを用いることにより、極低温環
境においても保持器２４，２９に良好な潤滑特性が得ら
れ、タッチダウン軸受の作動性は向上する。In particular, when used in a cryogenic environment, the use of PTFE as a solid lubricant provides good lubrication characteristics to the cages 24 and 29 even in a cryogenic environment, and the operability of the touch-down bearing is reduced. improves.
【００２８】上記の実施形態では、保持器２４，２９の
ポケット面２５ａと内径面２４ａの両方に固体潤滑剤被
膜が形成されているが、ポケット面２５ａと内径面２４
ａのいずれか一方に固体潤滑剤被膜を形成すれば、上記
のような効果を得ることが期待できる。但し、回転初期
時の潤滑特性を良好なものとするため、ポケット面２５
ａと内径面２４ａの両方に固体潤滑剤被膜を形成するの
が好ましい。In the above embodiment, the solid lubricant film is formed on both the pocket surface 25a and the inner diameter surface 24a of the cages 24, 29. However, the pocket surface 25a and the inner diameter surface 24 are formed.
If a solid lubricant film is formed on any one of a, the above-described effects can be expected. However, in order to improve the lubrication characteristics at the beginning of rotation, the pocket surface 25
Preferably, a solid lubricant film is formed on both the inner surface 24a and the inner surface 24a.
【００２９】なお、この実施形態では、保持器２４の内
径面２４ａが内輪２１の外径面により案内される形式
（内輪案内形式）であるが、保持器の外径面が外輪の内
径面により案内される形式（外輪案内形式）において
は、保持器の外径面とポケット面の少なくとも一方に固
体潤滑剤被覆を形成する。また、保持器がボールによっ
て案内される形式（転動体案内形式）においては、保持
器のポケット面に固体潤滑剤被膜を形成する。In this embodiment, the inner diameter surface 24a of the retainer 24 is guided by the outer diameter surface of the inner ring 21 (inner ring guide type), but the outer diameter surface of the retainer is determined by the inner diameter surface of the outer ring. In the guided type (outer ring guide type), a solid lubricant coating is formed on at least one of the outer diameter surface and the pocket surface of the cage. In a type in which the cage is guided by a ball (rolling member guide type), a solid lubricant film is formed on the pocket surface of the cage.
【００３０】[0030]
【発明の効果】本発明のタッチダウン軸受は、保持器が
所要の機械強度を有する材料で形成され、かつ保持器の
滑り摩擦を生ずる表面に固体潤滑剤被膜が形成されてい
るので、保持器に疲労が生じにくく、また、偏摩耗が生
じにくい。さらに、固体潤滑剤被膜の潤滑作用により、
ボールの円滑な自転・公転運動及び保持器の円滑な回転
運動が促進される。従って、本発明によれば、タッチダ
ウン軸受における回転運動の安定化、耐久性向上を図る
ことができる。According to the touch-down bearing of the present invention, the cage is formed of a material having a required mechanical strength, and a solid lubricant film is formed on a surface of the cage that causes sliding friction. Fatigue is less likely to occur, and uneven wear is less likely to occur. Furthermore, due to the lubrication effect of the solid lubricant film,
The smooth rotation / revolution of the ball and the smooth rotation of the cage are promoted. Therefore, according to the present invention, it is possible to stabilize the rotational motion and improve the durability of the touch-down bearing.
【００３１】また、極低温環境で使用されるものには固
体潤滑剤としてＰＴＦＥを用いることにより、極低温環
境での作動性も良好なものとすることができる。Further, by using PTFE as a solid lubricant for those used in an extremely low temperature environment, the operability in an extremely low temperature environment can be improved.
【図１】 本発明の一実施形態に係るタッチダウン軸受
の縦断面図。FIG. 1 is a longitudinal sectional view of a touch-down bearing according to an embodiment of the present invention.
【図２】 本発明の一実施形態に係る保持器の展開図。FIG. 2 is an expanded view of a retainer according to the embodiment of the present invention.
【図３】 本発明の一実施形態に係る保持器の斜視図。FIG. 3 is a perspective view of a retainer according to one embodiment of the present invention.
【図４】 従来の磁気軸受装置の縦断面図。FIG. 4 is a longitudinal sectional view of a conventional magnetic bearing device.
【図５】 従来のタッチダウン軸受の縦断面図。FIG. 5 is a longitudinal sectional view of a conventional touch-down bearing.
【図６】 従来の保持器の展開図。FIG. 6 is a development view of a conventional cage.
１…回転軸 ２…磁気軸受 ６…タッチダウン
軸受 ７…ハウジング ２１，２６…内輪 ２１ａ，２２ａ，２６ａ，２７ａ…軌道面 ２２，２７…外輪 ２３，２８…ボー
ル ２４，２９…保持器 ２５ａ，３０ａ…
ポケット面 ２４ａ…内径面DESCRIPTION OF SYMBOLS 1 ... Rotating shaft 2 ... Magnetic bearing 6 ... Touch-down bearing 7 ... Housing 21, 26 ... Inner ring 21a, 22a, 26a, 27a ... Track surface 22, 27 ... Outer ring 23, 28 ... Ball 24, 29 ... Retainer 25a, 30a …
Pocket surface 24a ... inner diameter surface
Claims (3)
に転動自在に介装された複数のボールと、各ボールを円
周所定間隔に保持する保持器とを有し、固定側に配設さ
れた磁気軸受により非接触状態で支持される回転部材
を、タッチダウン時に支持するタッチダウン軸受におい
て、 上記保持器が軟鋼、ステンレス鋼、セラミックス等の所
要の機械強度を有する材料からなり、かつ、保持器の滑
り摩擦を生ずる表面に固体潤滑剤被膜が形成されている
ことを特徴とする磁気軸受装置のタッチダウン軸受。An inner ring, an outer ring, a plurality of balls rotatably interposed between the raceways of the inner and outer rings, and a retainer for holding the balls at predetermined circumferential intervals; In a touch-down bearing for supporting a rotating member supported in a non-contact state by a magnetic bearing disposed on a fixed side at the time of touch-down, the retainer has a required mechanical strength such as mild steel, stainless steel, ceramics or the like. A touch-down bearing for a magnetic bearing device, characterized in that a solid lubricant film is formed on a surface of the cage that causes sliding friction.
鉛被膜であることを特徴とする請求項１の磁気軸受装置
のタッチダウン軸受。2. The touch-down bearing for a magnetic bearing device according to claim 1, wherein said solid lubricant coating is a PTFE coating or a lead coating.
〜２ｍｍであることを特徴とする請求項１又は請求項２
の磁気軸受装置のタッチダウン軸受装置。3. The solid lubricant film having a thickness of 0.5 μm
3. The method according to claim 1, wherein the distance is about 2 mm.
Touch-down bearing device of magnetic bearing device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9252307A JPH1182522A (en) | 1997-09-17 | 1997-09-17 | Touchdown bearing for magnetic bearing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9252307A JPH1182522A (en) | 1997-09-17 | 1997-09-17 | Touchdown bearing for magnetic bearing device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH1182522A true JPH1182522A (en) | 1999-03-26 |
Family
ID=17235439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9252307A Withdrawn JPH1182522A (en) | 1997-09-17 | 1997-09-17 | Touchdown bearing for magnetic bearing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH1182522A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617733B1 (en) * | 1999-03-31 | 2003-09-09 | Seiko Instruments Inc. | Magnetic bearing apparatus and vacuum pump having magnetic bearing apparatus |
| JP2009236232A (en) * | 2008-03-27 | 2009-10-15 | Ntn Corp | Roller bearing |
| JP2012172801A (en) * | 2011-02-23 | 2012-09-10 | Nsk Ltd | Matched mounting angular contact ball bearing |
| WO2012152539A1 (en) * | 2011-05-12 | 2012-11-15 | Schaeffler Technologies AG & Co. KG | Bearing arrangement with a back-up bearing, in particular for mounting the rapidly rotating shaft of a compressor |
| WO2012152541A1 (en) * | 2011-05-12 | 2012-11-15 | Schaeffler Technologies AG & Co. KG | Bearing arrangement with a back-up bearing, in particular for mounting a rapidly rotating shaft |
| US8485730B2 (en) | 2008-03-27 | 2013-07-16 | Ntn Corporation | Rolling bearing |
-
1997
- 1997-09-17 JP JP9252307A patent/JPH1182522A/en not_active Withdrawn
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617733B1 (en) * | 1999-03-31 | 2003-09-09 | Seiko Instruments Inc. | Magnetic bearing apparatus and vacuum pump having magnetic bearing apparatus |
| JP2009236232A (en) * | 2008-03-27 | 2009-10-15 | Ntn Corp | Roller bearing |
| US8485730B2 (en) | 2008-03-27 | 2013-07-16 | Ntn Corporation | Rolling bearing |
| JP2012172801A (en) * | 2011-02-23 | 2012-09-10 | Nsk Ltd | Matched mounting angular contact ball bearing |
| WO2012152539A1 (en) * | 2011-05-12 | 2012-11-15 | Schaeffler Technologies AG & Co. KG | Bearing arrangement with a back-up bearing, in particular for mounting the rapidly rotating shaft of a compressor |
| WO2012152541A1 (en) * | 2011-05-12 | 2012-11-15 | Schaeffler Technologies AG & Co. KG | Bearing arrangement with a back-up bearing, in particular for mounting a rapidly rotating shaft |
| CN103534500A (en) * | 2011-05-12 | 2014-01-22 | 谢夫勒科技股份两合公司 | Bearing arrangement with a back-up bearing, in particular for mounting a rapidly rotating shaft |
| CN103534500B (en) * | 2011-05-12 | 2016-03-30 | 舍弗勒技术股份两合公司 | There is the bearing arrangement of support bearing, especially for the axle of supporting quick rotation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3529191B2 (en) | Method of manufacturing spherical roller bearing with cage and cage for spherical roller bearing with cage | |
| JPH1182522A (en) | Touchdown bearing for magnetic bearing device | |
| US3845999A (en) | Bearing assembly | |
| JP3480000B2 (en) | Rolling bearing | |
| JP2597103B2 (en) | Cylindrical roller bearing | |
| JPS6224025A (en) | Rolling bearing | |
| JP2020070857A (en) | Slewing bearing | |
| JP2611393B2 (en) | Solid lubricated ball bearings | |
| JPH05209621A (en) | Touch-down bearing for magnetic bearing device | |
| JP2000120707A (en) | Rolling bearing | |
| JP6861407B1 (en) | bearing | |
| JP2010025191A (en) | Self-aligning roller bearing | |
| JPH102326A (en) | Composite bearing | |
| JP2003120683A (en) | Thrust roller bearing | |
| JP2007333084A (en) | Cage for bearing | |
| JP2006125604A (en) | Thrust roller bearing | |
| JP2012202487A (en) | Rolling bearing device | |
| JPH05209620A (en) | Touch-down bearing for magnetic bearing device | |
| JP2000337368A (en) | Full type rolling roller bearing | |
| JPH11336772A (en) | Rolling bearing | |
| JP2000205250A (en) | Rolling bearing | |
| JPH1089364A (en) | Solid lubricated cross roller bearing | |
| JP2009210078A (en) | Self-aligning roller bearing | |
| JP2000274437A (en) | Rolling bearing | |
| JPH1182496A (en) | Thrust automatic aligning roller bearing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20041207 |