JP2520743B2 - Magnetic fluid seal device - Google Patents
Magnetic fluid seal deviceInfo
- Publication number
- JP2520743B2 JP2520743B2 JP1248695A JP24869589A JP2520743B2 JP 2520743 B2 JP2520743 B2 JP 2520743B2 JP 1248695 A JP1248695 A JP 1248695A JP 24869589 A JP24869589 A JP 24869589A JP 2520743 B2 JP2520743 B2 JP 2520743B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic fluid
- receiving member
- holding
- rotation receiving
- peripheral edge
- 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
Landscapes
- Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
- Sealing Of Bearings (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は磁性流体シール装置に関する。The present invention relates to a magnetic fluid seal device.
従来、第4図に例示するような軸固定型のスピンドル
モータに於て、磁性流体シール装置Sは磁性流体aに作
用する遠心力により該磁性流体aが飛散する問題が生じ
ていた。即ち、矢印Mのように回転するロータb側に、
平板環状マグネットc及びポールピースe,eの外周縁を
固着し、一体に回転させると共に、固定軸fの外周面
と、該ポールピースeの内周縁との微小間隙部に、磁性
流体aを注入し保持させていた。Conventionally, in the fixed shaft type spindle motor as illustrated in FIG. 4, the magnetic fluid sealing device S has a problem that the magnetic fluid a is scattered by the centrifugal force acting on the magnetic fluid a. That is, on the side of the rotor b that rotates as indicated by the arrow M,
The flat ring magnet c and the outer peripheral edges of the pole pieces e, e are fixed and rotated integrally, and the magnetic fluid a is injected into a minute gap between the outer peripheral surface of the fixed shaft f and the inner peripheral edge of the pole piece e. I was holding it.
そのため、第5図に示すように、磁性流体aが固定軸
fと接触する部分(ここでは周速度は零のため)の遠心
力Fiは零であるのに対して、ポールピースeの内周縁に
接する部分には大きな遠心力Foが作用する。けだし、ポ
ールピースeは高速回転するために、これに接する磁性
流体aの外周寄りの部分も高速回転して、大きい遠心力
Foが作用する。この遠心力Foが、磁気による磁性流体の
拘束力(表面張力及び吸着力)より大きくなり、磁性流
体aは、ポールピースeの表面gを伝って、外径方向へ
飛散することとなる。Therefore, as shown in FIG. 5, the centrifugal force Fi of the portion where the magnetic fluid a contacts the fixed shaft f (here, the peripheral velocity is zero) is zero, while the inner peripheral edge of the pole piece e is zero. A large centrifugal force Fo acts on the part in contact with. Since the pole piece e rotates at a high speed, a portion of the magnetic fluid a which is in contact with the pole piece e near the outer periphery also rotates at a high speed, and a large centrifugal force is generated.
Fo acts. This centrifugal force Fo becomes larger than the magnetic force restraining force (surface tension and attracting force) of the magnetic fluid, and the magnetic fluid a propagates along the surface g of the pole piece e and scatters in the outer diameter direction.
本発明は上記課題を解決するために、回転円筒体と固
定軸の間に介装される磁性流体シール装置に於て;回転
円筒体と固定軸の間に介装される磁性流体シール装置に
於て;該回転軸の外周面に対して間隙をもって包囲する
円筒部と、上記回転円筒体に固着される取付部と、該円
筒部と取付部とを連結する連結部とを有し、該円筒部と
取付部と連結部とから軸心方向外方へ開口する円環状凹
所を形成した磁性材製回転受け部材と;該回転受け部材
の円環状凹所に遊嵌状に嵌入する保持筒部と、上記固定
軸の一部に直接又は間接に固着される取付部と、該取付
部と保持筒部とを連結して該保持筒部の外方開口部を施
蓋状とする平板環状の連結部とを有するシール本体保持
部材と;マグネットとポールピースからなり、かつ、上
記保持筒部の内周端縁にその外周端縁が保持されて、そ
のポールピースの内端縁が上記円筒部の外周面に微小間
隙部をもって対向し、上記回転受け部材の連結部と上記
シール本体保持部材の連結部との間に介在される磁性流
体シール本体と;上記磁性流体シール本体のポールピー
スの内周端縁と上記回転受け部材の円筒部の外周面との
間に形成される微小間隙部に保持される磁性流体と;を
備えている。In order to solve the above problems, the present invention provides a magnetic fluid seal device interposed between a rotary cylinder and a fixed shaft; a magnetic fluid seal device interposed between the rotary cylinder and a fixed shaft. A cylindrical portion that surrounds the outer peripheral surface of the rotating shaft with a gap, an attaching portion that is fixed to the rotating cylindrical body, and a connecting portion that connects the cylindrical portion and the attaching portion, A rotation receiving member made of a magnetic material, which has an annular recess opening outward in the axial direction from the cylindrical portion, the mounting portion, and the connecting portion; and a retainer that is loosely fitted into the annular recess of the rotation receiving member. A cylindrical portion, a mounting portion that is directly or indirectly fixed to a part of the fixed shaft, and a flat plate that connects the mounting portion and the holding tubular portion and forms the outer opening of the holding tubular portion into a lid-like shape. A seal body holding member having an annular connecting portion; a magnet and a pole piece, and an inner peripheral end of the holding cylinder portion The outer peripheral edge of the pole piece is held by the inner peripheral edge of the pole piece and the inner peripheral edge of the pole piece faces the outer peripheral surface of the cylindrical portion with a minute gap. A magnetic fluid seal body interposed therebetween; magnetism retained in a minute gap formed between the inner peripheral edge of the pole piece of the magnetic fluid seal body and the outer peripheral surface of the cylindrical portion of the rotation receiving member. And a fluid.
磁性材製回転受け部材の円筒部の外周面と、静止した
磁性流体シール本体の内周端縁との間に、磁性流体が円
環状に保持され、しかも、該円環状磁性流体は、内周縁
が上記円筒部と共に回転運動するが、外周縁は上記シー
ル本体と共に静止乃至低速の回転運動である。即ち、回
転受け部材の円筒部の外周面側の磁性流体には大きな遠
心力が作用し、逆に、ポールピース側の磁性流体には零
又は僅かな遠心力しか作用せず、磁性流体の拘束力(表
面張力及び吸着力)が、ポールピース側の遠心力より優
っていて、常に元の位置−微小間隙部−に保持されてい
る。The magnetic fluid is held in an annular shape between the outer peripheral surface of the cylindrical portion of the magnetic material rotation receiving member and the inner peripheral edge of the stationary magnetic fluid seal body, and the annular magnetic fluid has an inner peripheral edge. Rotates with the cylindrical portion, but the outer peripheral edge of the seal body has a stationary or low-speed rotational movement. That is, a large centrifugal force acts on the magnetic fluid on the outer peripheral surface side of the cylindrical portion of the rotation receiving member, and conversely, only zero or a slight centrifugal force acts on the magnetic fluid on the pole piece side, and the magnetic fluid is restrained. The force (surface tension and suction force) is superior to the centrifugal force on the pole piece side and is always held in the original position-the minute gap portion.
仮に、磁性流体の保持状態が解除されて該磁性流体が
軸心方向内方側に飛散したとしても、回転受け部材の連
結部乃至取付部にて受けられ、逆に、磁性流体が軸心方
向外方側に飛散したとしても、シール本体保持部材の連
結部乃至保持筒部にて受けられ、モータ外部に飛散する
ことはない。Even if the holding state of the magnetic fluid is released and the magnetic fluid is scattered inward in the axial direction, the magnetic fluid is received by the connecting portion or mounting portion of the rotation receiving member, and conversely, the magnetic fluid is moved in the axial direction. Even if it scatters to the outside, it is received by the connecting part or the holding cylinder of the seal body holding member and does not scatter to the outside of the motor.
以下、図示の実施例に基づき本発明を詳説する。 Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
第1図は本発明に係る磁性流体シール装置1,1を使用
した軸固定型のスピンドルモータを示し、このモータ
は、固定軸2にステータ3を固着し、一対の軸受4,4を
介してハブ5が回転自在に該固定軸2に枢着されてい
る。6はブラケットであって図外の他部材に固着され
る。FIG. 1 shows a fixed shaft type spindle motor using the magnetic fluid sealing device 1, 1 according to the present invention. In this motor, a stator 3 is fixed to a fixed shaft 2 and a pair of bearings 4 and 4 are used. A hub 5 is rotatably attached to the fixed shaft 2. Reference numeral 6 denotes a bracket which is fixed to another member (not shown).
ハブ5は、内周側にヨーク7を有し、かつ、ステータ
3に対応する軸方向位置にはロータマグネット8が上記
ヨーク7内周面に固着されている。The hub 5 has a yoke 7 on the inner peripheral side, and a rotor magnet 8 is fixed to the inner peripheral surface of the yoke 7 at an axial position corresponding to the stator 3.
このように、ハブ5とヨーク7等から成る回転円筒体
9と、固定軸2の間に、第1図では一対の磁性流体シー
ル装置1,1が介装される。In this way, a pair of magnetic fluid seal devices 1, 1 are interposed between the rotating cylindrical body 9 including the hub 5 and the yoke 7 and the fixed shaft 2 in FIG.
第2図は第1図の左側の磁性流体シール装置1の要部
拡大図である。この第2図及び第1図に於て、10は、平
板環状マグネット11と、これを両面から挟着する平板環
状ポールピース12,12から成る磁性流体シール本体であ
る。FIG. 2 is an enlarged view of a main part of the magnetic fluid seal device 1 on the left side of FIG. In FIG. 2 and FIG. 1, 10 is a magnetic fluid seal main body composed of a flat plate annular magnet 11 and flat plate annular pole pieces 12, 12 sandwiching the flat plate magnet 11 from both sides.
13は磁性材製の回転受け部材であり、該受け部材13
は、固定軸2の外周面に対して間隙をもって包囲する円
筒部14を有し、かつ、回転円筒体9のヨーク7の一端内
周面に嵌合して固着される円筒状の取付部15、及び、上
記円筒部14と該取付部15とを連結する平板環状の連結部
16とを有する。即ち、該受け部材13は、横断面に於て、
モータの外方へ開口する円環状凹所17を形成するコの字
型である。Reference numeral 13 denotes a rotation receiving member made of a magnetic material.
Has a cylindrical portion 14 that surrounds the outer peripheral surface of the fixed shaft 2 with a gap, and is a cylindrical mounting portion 15 that is fitted and fixed to one end inner peripheral surface of the yoke 7 of the rotating cylindrical body 9. , And a flat plate annular connecting portion that connects the cylindrical portion 14 and the mounting portion 15
With 16. That is, the receiving member 13 has a horizontal cross section.
It is a U-shape that forms an annular recess 17 that opens to the outside of the motor.
18はシール本体保持部材であり、円筒部14の外周面に
対して、シール本体10の幅寸法よりも僅かに大きい所定
間隔をもって対向する保持筒部19を有し、この保持筒部
19の内周面に、シール本体10の外周縁が嵌着保持され
る。つまり、固定軸2、円筒部14、シール本体10、保持
筒部19、取付部15、及びヨーク7が、同心状に配設され
ている。また、20は固定軸2の一端に直接に外嵌状に固
着される円筒状の取付部であり、21は、この取付部20と
保持筒部19を連結する平板環状の連結部であり、図例で
は、シール本体保持部材18は、保持筒部19と連結部21と
取付部20とから構成され、横断面がZ字型を呈する。Reference numeral 18 denotes a seal body holding member, which has a holding cylinder portion 19 facing the outer peripheral surface of the cylindrical portion 14 with a predetermined interval slightly larger than the width dimension of the seal body 10, and this holding cylinder portion.
The outer peripheral edge of the seal body 10 is fitted and held on the inner peripheral surface of 19. That is, the fixed shaft 2, the cylindrical portion 14, the seal body 10, the holding tubular portion 19, the mounting portion 15, and the yoke 7 are arranged concentrically. Further, 20 is a cylindrical mounting portion that is directly fixed to one end of the fixed shaft 2 in an externally fitted shape, and 21 is a flat plate annular connecting portion that connects the mounting portion 20 and the holding tubular portion 19, In the illustrated example, the seal body holding member 18 includes a holding tube portion 19, a connecting portion 21, and a mounting portion 20, and has a Z-shaped cross section.
そして、(第2図で明らかな如く、)連結部21には適
数個(例えば周方向に実質上等間隔を置いて3個)の注
入孔22が貫設されると共に、ポリエステル等のプラスチ
ック製の盲蓋23がこの注入孔22を閉じるように貼着され
ている。Then, as is apparent from FIG. 2, a suitable number of injection holes 22 (for example, three at substantially equal intervals in the circumferential direction) are formed in the connecting portion 21, and a plastic such as polyester is formed. A blind lid 23 made of metal is attached so as to close the injection hole 22.
26,26は、静止したシール本体10のポールピース12,12
の内周縁部24と、回転する円筒部14の外周面との間に形
成された微小間隙部25に保持される磁性流体である。円
筒部14が磁性材であるから、磁性流体26,26は第2図の
ように確実に保持される。26,26 are the pole pieces 12,12 of the stationary seal body 10.
The magnetic fluid is retained in a minute gap portion 25 formed between the inner peripheral edge portion 24 and the outer peripheral surface of the rotating cylindrical portion 14. Since the cylindrical portion 14 is made of a magnetic material, the magnetic fluids 26, 26 are securely held as shown in FIG.
この第2図を従来の第4図と比較すれば明らかなよう
に、本発明ではシール本体10は固定側に取付けられ、磁
性流体26の内周縁が回転する部材(円筒部14)に接触し
ていて、従来の軸固定型スピンドルモータとは、全く逆
の対応関係に構成される。As is clear from comparing FIG. 2 with FIG. 4 of the prior art, in the present invention, the seal body 10 is mounted on the fixed side, and the inner peripheral edge of the magnetic fluid 26 comes into contact with the rotating member (cylindrical portion 14). However, it has a completely opposite correspondence relationship with the conventional fixed shaft type spindle motor.
これによって、第3図に示す如く、磁性流体26はその
内周縁の受ける遠心力Fiが大きいが、静止したポールピ
ース12,12と接触する外周縁の受ける遠心力Foの遠心力
は零又は極めて小さい。磁性流体26の拘束力(表面張力
及び吸着力)が、磁性流体26の外周縁側に於て、遠心力
Foよりも十分に大きいため、磁性流体26は、ポールピー
ス12の表面を伝わらず、外径方向に飛散することがな
い。As a result, as shown in FIG. 3, the magnetic fluid 26 has a large centrifugal force Fi on its inner peripheral edge, but the centrifugal force Fo on the outer peripheral edge that contacts the stationary pole pieces 12, 12 is zero or extremely high. small. The binding force (surface tension and adsorption force) of the magnetic fluid 26 is a centrifugal force on the outer peripheral edge side of the magnetic fluid 26.
Since it is sufficiently larger than Fo, the magnetic fluid 26 does not propagate on the surface of the pole piece 12 and does not scatter in the outer diameter direction.
なお、第2図に於て、注入孔22は(盲蓋23の貼着前の
状態にて)注入具をここから挿入して、磁性流体26を微
小間隙部25へ注入するための孔であり、注入作業の後
に、盲蓋23を貼着する。In FIG. 2, the injection hole 22 is a hole for inserting the injection tool from here (before attaching the blind lid 23) to inject the magnetic fluid 26 into the minute gap portion 25. Yes, the blind lid 23 is attached after the injection work.
また、第2図の構造に於て、仮に内側の磁性流体26が
飛散しようとした場合には、連結部16と取付部15との隅
部27に付着して、モータの外方へは飛び難い利点があ
る。特に、この隅部27に凹溝28を図のように形成するも
望ましい。さらに、仮に外側の磁性流体26が飛散しよう
とした場合には、取付部19と連結部21との隅部29に付着
して、モータの外方へは飛散することがない。Further, in the structure of FIG. 2, if the magnetic fluid 26 on the inner side tries to scatter, it will adhere to the corner 27 between the connecting portion 16 and the mounting portion 15, and will fly to the outside of the motor. There are difficult advantages. In particular, it is also desirable to form the groove 28 in the corner 27 as shown in the figure. Further, if the magnetic fluid 26 on the outer side tries to scatter, it adheres to the corner 29 between the mounting portion 19 and the connecting portion 21 and does not scatter to the outside of the motor.
なお、第1図に於て、さらに確実な飛散防止のために
アルミ製等のシールキャップ30を圧入等にてハブ5の開
口端に固着している。In addition, in FIG. 1, a seal cap 30 made of aluminum or the like is fixed to the open end of the hub 5 by press fitting or the like in order to further prevent the scattering.
次に、第1図の右側の磁性流体シール装置1も、(第
2図にて説明した構成と)同様の構成であるが、シール
本体保持部材18を、ブラケット6に固着しても良いこと
を示している。また、受け部材13は軸受用スペーサ31を
介して取付けられている。Next, the magnetic fluid seal device 1 on the right side of FIG. 1 also has the same configuration (as described in FIG. 2), but the seal body holding member 18 may be fixed to the bracket 6. Is shown. Further, the receiving member 13 is attached via a bearing spacer 31.
なお、本発明は図示の実施例に限定されず、設計変更
自由であって、スピンドルモータとしては軸固定型であ
れば各種の形状のもの、及び各種用途のものに、適用可
能である。また、シール本体10としては、ポールピース
12が1枚のものとすることも好ましいことがあり、ある
いは、2枚のポールピース12,12の内の1方にのみ磁性
流体26を注入して保持するも自由である。The present invention is not limited to the embodiment shown in the drawings, the design can be freely changed, and the spindle motor can be applied to various shapes as long as the shaft is of a fixed type and various uses. Also, as the seal body 10, a pole piece
It may also be preferable to have one 12 pieces, or it is free to inject and hold the magnetic fluid 26 in only one of the two pole pieces 12, 12.
本発明は上述の如く構成されているので、次に記載す
る効果を奏する。Since the present invention is configured as described above, it has the following effects.
磁性流体26において、回転受け部材13の円筒部14と接
触する側(以下、回転側)は、回転によって大きな遠心
力Fiが作用し、この流体の一部は径方向外方へ流動す
る。一方、磁性流体26において、固定軸2に取付けられ
ているシール本体10と接触する側(以下、静止側)は、
磁性流体26が静止しているため、実質上遠心力Foは作用
せず(仮に、作用したとしても非常に小さい。)、上述
(回転側)のように流動することはない。In the magnetic fluid 26, a large centrifugal force Fi acts on the side of the rotation receiving member 13 that contacts the cylindrical portion 14 (hereinafter referred to as the rotation side), and a part of this fluid flows radially outward. On the other hand, in the magnetic fluid 26, the side in contact with the seal body 10 attached to the fixed shaft 2 (hereinafter, the stationary side) is
Since the magnetic fluid 26 is stationary, the centrifugal force Fo does not substantially act (if it acts, it is very small), and does not flow like the above (rotation side).
以上のような状態にある磁性流体26は、磁性流体26の
拘束力(表面張力及び磁性吸着力)が静止側の遠心力Fo
よりも十分に大きいため、確実に保持されポールピース
12の表面に沿って流動することはなく飛散が防止され
る。従って、ディスクモータ等に於てディスク室の汚染
を防止できる。In the magnetic fluid 26 in the above-described state, the binding force (surface tension and magnetic attraction force) of the magnetic fluid 26 is the centrifugal force Fo on the stationary side.
Large enough to be securely held and pole pieces
It does not flow along the surface of 12 and scattering is prevented. Therefore, it is possible to prevent contamination of the disk chamber in the disk motor or the like.
仮に、磁性流体26が微小間隙部25から飛散したとして
も、次のようにしてモータ外部への飛散が防止される。
即ち、シール本体10より軸心方向内方側においては、回
転受け部材13とシール本体保持部18とシール本体10とで
規定される収容空間にて、飛散した磁性流体26が受けら
れる。一方、シール本体10より軸心方向外方側において
は、シール本体保持部18の保持筒部19と連結部21とシー
ル本体10によって規定される収容空間にて、飛散した磁
性流体が受けられる。Even if the magnetic fluid 26 scatters from the minute gap portion 25, scattering to the outside of the motor is prevented as follows.
That is, on the inner side of the seal body 10 in the axial direction, the scattered magnetic fluid 26 is received in the accommodation space defined by the rotation receiving member 13, the seal body holding portion 18, and the seal body 10. On the other hand, on the axially outer side of the seal body 10, the scattered magnetic fluid is received in the accommodation space defined by the holding cylinder portion 19 of the seal body holding portion 18, the connecting portion 21, and the seal body 10.
第1図は本発明の一実施例を示す要部断面図、第2図は
第1図の要部拡大図、第3図は作用説明図である。第4
図は従来例の要部断面図、第5図はその作用説明図であ
る。 2……固定軸、9……回転円筒体、10……シール本体、
11……マグネット、12……ポールピース、13……受け部
材、14……円筒部、15……取付部、16……連結部、18…
…シール本体保持部材、19……保持筒部、20……取付
部、24……内周縁部、25……微小間隙、26……磁性流
体、Fo,Fi……遠心力。FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention, FIG. 2 is an enlarged view of an essential part of FIG. 1, and FIG. Fourth
FIG. 5 is a sectional view of a main part of a conventional example, and FIG. 2 ... Fixed shaft, 9 ... Rotating cylinder, 10 ... Seal body,
11 ... Magnet, 12 ... Pole piece, 13 ... Receiving member, 14 ... Cylindrical part, 15 ... Mounting part, 16 ... Coupling part, 18 ...
… Seal body holding member, 19 …… Holding cylinder part, 20 …… Mounting part, 24 …… Inner peripheral edge part, 25 …… Small gap, 26 …… Magnetic fluid, Fo, Fi …… Centrifugal force.
Claims (1)
磁性流体シール装置に於て、 該固定軸2の外周面に対して間隙をもって包囲する円筒
部14と、上記回転円筒体9に固着される取付部15と、該
円筒部14と取付部15とを連結する連結部16とを有し、該
円筒部14と取付部15と連結部16とから軸心方向外方へ開
口する円環状凹所17を形成した磁性材製回転受け部材13
と、 該回転受け部材13の円環状凹所17に遊嵌状に嵌入する保
持筒部19と、上記固定軸2の一部に直接又は間接に固着
される取付部20と、該取付部20と保持筒部19とを連結し
て該保持筒部19の外方開口部を施蓋状とする平板環状の
連結部21とを有するシール本体保持部材18と、 マグネット11とポールピース12からなり、かつ、上記保
持筒部19の内周端縁にその外周端縁が保持されて、その
ポールピース12の内周端縁24が上記回転受け部材13の円
筒部14の外周面に微小間隙部25をもって対向し、上記回
転受け部材13の連結部16と上記シール本体保持部材18の
連結部21との間に介在される磁性流体シール本体10と、 上記磁性流体シール本体10のポールピース12の内周端縁
24と上記回転受け部材13の円筒部14の外周面との間に形
成される微小間隙部25に保持される磁性流体26と、 を備えたことを特徴とする磁性流体シール装置。1. A magnetic fluid seal device interposed between a rotating cylinder body 9 and a fixed shaft 2, wherein a cylindrical portion 14 surrounds the outer peripheral surface of the fixed shaft 2 with a gap, and the rotating cylinder. A mounting portion 15 fixed to the body 9 and a connecting portion 16 connecting the cylindrical portion 14 and the mounting portion 15 are provided. The cylindrical portion 14, the mounting portion 15 and the connecting portion 16 are axially outward from the connecting portion 16. Rotation receiving member 13 made of magnetic material having an annular recess 17 opening to
A holding cylinder portion 19 that is loosely fitted into the annular recess 17 of the rotation receiving member 13, an attachment portion 20 that is directly or indirectly fixed to a portion of the fixed shaft 2, and the attachment portion 20. A seal body holding member 18 having a flat plate annular connecting portion 21 that connects the holding tubular portion 19 with the holding tubular portion 19 and forms an outer opening of the holding tubular portion 19 into a lid shape, and includes a magnet 11 and a pole piece 12. Also, the outer peripheral edge is held by the inner peripheral edge of the holding tubular portion 19, the inner peripheral edge 24 of the pole piece 12 is a minute gap portion on the outer peripheral surface of the cylindrical portion 14 of the rotation receiving member 13. The magnetic fluid seal main body 10 facing each other with 25 and interposed between the connecting portion 16 of the rotation receiving member 13 and the connecting portion 21 of the seal main body holding member 18, and the pole piece 12 of the magnetic fluid seal main body 10. Inner peripheral edge
A magnetic fluid sealing device comprising: a magnetic fluid 26 held in a minute gap portion 25 formed between the rotation receiving member 13 and the outer peripheral surface of the cylindrical portion 14 of the rotation receiving member 13.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1248695A JP2520743B2 (en) | 1989-09-25 | 1989-09-25 | Magnetic fluid seal device |
US07/587,249 US5061868A (en) | 1989-09-25 | 1990-09-24 | Spindle motor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1248695A JP2520743B2 (en) | 1989-09-25 | 1989-09-25 | Magnetic fluid seal device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH03113180A JPH03113180A (en) | 1991-05-14 |
JP2520743B2 true JP2520743B2 (en) | 1996-07-31 |
Family
ID=17181961
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1248695A Expired - Fee Related JP2520743B2 (en) | 1989-09-25 | 1989-09-25 | Magnetic fluid seal device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2520743B2 (en) |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0160023U (en) * | 1987-10-12 | 1989-04-17 |
-
1989
- 1989-09-25 JP JP1248695A patent/JP2520743B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH03113180A (en) | 1991-05-14 |
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