JP2009014121A - Dynamic pressure bearing device and its manufacturing method - Google Patents

Dynamic pressure bearing device and its manufacturing method Download PDF

Info

Publication number
JP2009014121A
JP2009014121A JP2007177553A JP2007177553A JP2009014121A JP 2009014121 A JP2009014121 A JP 2009014121A JP 2007177553 A JP2007177553 A JP 2007177553A JP 2007177553 A JP2007177553 A JP 2007177553A JP 2009014121 A JP2009014121 A JP 2009014121A
Authority
JP
Japan
Prior art keywords
housing
peripheral surface
thrust bearing
bearing device
thrust
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Withdrawn
Application number
JP2007177553A
Other languages
Japanese (ja)
Inventor
Kazuto Shimizu
一人 清水
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NTN Corp
Original Assignee
NTN Corp
NTN Toyo Bearing Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NTN Corp, NTN Toyo Bearing Co Ltd filed Critical NTN Corp
Priority to JP2007177553A priority Critical patent/JP2009014121A/en
Publication of JP2009014121A publication Critical patent/JP2009014121A/en
Withdrawn legal-status Critical Current

Links

Images

Landscapes

  • Sliding-Contact Bearings (AREA)
  • Support Of The Bearing (AREA)
  • Mounting Of Bearings Or Others (AREA)
  • Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dynamic pressure bearing device and its manufacturing method capable of setting a clearance width of a thrust bearing clearance at low cost without lowering a loading capacity in a thrust direction. <P>SOLUTION: A housing 7 and a sleeve part 8 are brought in a mutually immobile state while the thrust bearing clearance is set to be zero and then an outer circumferential surface 7a2 of a housing side part 7a are pressed. The housing side part 7a is extended in an axial direction by a plastic flow of a material due to this pressure and a first and a second thrust bearing clearances are formed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、動圧軸受装置及びその製造方法に関するものである。   The present invention relates to a hydrodynamic bearing device and a manufacturing method thereof.

動圧軸受装置は、情報機器、例えばＨＤＤ等の磁気ディスク駆動装置、ＣＤ−ＲＯＭ、ＣＤ−Ｒ／ＲＷ、ＤＶＤ−ＲＯＭ／ＲＡＭ等の光ディスク駆動装置、ＭＤ、ＭＯ等の光磁気ディスク駆動装置等のスピンドルモータ用、レーザビームプリンタ（ＬＢＰ）のポリゴンスキャナモータ用、プロジェクタのカラーホイール用、あるいは電気機器の冷却ファン等に使用されるファンモータなどの小型モータ用として好適に使用可能である。   The hydrodynamic bearing device is an information device, for example, a magnetic disk drive device such as HDD, an optical disk drive device such as CD-ROM, CD-R / RW, DVD-ROM / RAM, a magneto-optical disk drive device such as MD, MO, etc. It can be preferably used for a small motor such as a fan motor used for a spindle motor, a laser scanner for a laser beam printer (LBP), a color wheel for a projector, or a cooling fan for an electric device.

例えば、特許文献１および特許文献２に示されている動圧軸受装置は、側部および底部を有するコップ状のハウジングと、ハウジングの内周に固定された軸受スリーブと、フランジ部を有する軸部材とを備える。軸受スリーブの内周面と軸部材の外周面との間にはラジアル軸受隙間が形成され、フランジ部の上側端面と軸受スリーブの下側端面との間、およびフランジ部の下側端面とハウジング底部の上側端面との間にそれぞれスラスト軸受隙間が形成される。軸部材が回転すると、各軸受隙間の潤滑流体に動圧が発生し、この動圧作用により軸部材がラジアル方向およびスラスト方向に非接触支持される。   For example, a hydrodynamic bearing device disclosed in Patent Literature 1 and Patent Literature 2 includes a cup-shaped housing having a side portion and a bottom portion, a bearing sleeve fixed to the inner periphery of the housing, and a shaft member having a flange portion. With. A radial bearing gap is formed between the inner peripheral surface of the bearing sleeve and the outer peripheral surface of the shaft member, between the upper end surface of the flange portion and the lower end surface of the bearing sleeve, and the lower end surface of the flange portion and the bottom of the housing. Thrust bearing gaps are respectively formed between the upper end surfaces of the two. When the shaft member rotates, dynamic pressure is generated in the lubricating fluid in each bearing gap, and the dynamic pressure action causes the shaft member to be supported in a non-contact manner in the radial direction and the thrust direction.

特開２００５−２８２７７９号公報JP 2005-28279 A 特開２００２−６１６３７号公報JP 2002-61637 A

このような動圧軸受装置の軸受隙間の隙間幅は動圧効果に大きな影響を与えるため、できるだけ高精度に設定することが望ましい。しかし、上記のようにハウジングがコップ状である場合はスラスト軸受隙間の隙間幅の設定は困難であるため、様々な方法でスラスト軸受隙間を高精度に設定する工夫がなされている。   Since the gap width of the bearing gap of such a hydrodynamic bearing device has a great influence on the hydrodynamic effect, it is desirable to set it as highly accurate as possible. However, since it is difficult to set the clearance width of the thrust bearing gap when the housing is cup-shaped as described above, various methods have been devised to set the thrust bearing gap with high accuracy.

例えば、特許文献１に示される動圧軸受装置は、ハウジングの内周に段部を設け、その段部に軸受スリーブの下側端面を当接させて位置決めすることにより、スラスト軸受隙間の隙間幅を設定している。また、特許文献２に示される動圧軸受装置は、ハウジング底部の上側端面と軸受スリーブの下側端面との間に、両面に当接する位置決め部材を設けることにより、スラスト軸受隙間の隙間幅を設定している。   For example, in the hydrodynamic bearing device disclosed in Patent Document 1, a stepped portion is provided on the inner periphery of the housing, and the lower end surface of the bearing sleeve is brought into contact with the stepped portion to be positioned. Is set. Further, the hydrodynamic bearing device disclosed in Patent Document 2 sets the clearance width of the thrust bearing gap by providing a positioning member that contacts both surfaces between the upper end surface of the housing bottom and the lower end surface of the bearing sleeve. is doing.

しかしながら、上記の何れの方法も、ハウジングの段部、あるいは位置決め部材を必要するため、工程数や部材数が増加する。さらに、このような段部あるいは位置決め部材をハウジングの内周に設けることにより、これらを設けない場合と比べてフランジ部の径方向寸法が縮小されるため、フランジ部に形成されるスラスト軸受面の面積が減少し、スラスト方向の負荷能力の低下を招くこととなる。   However, any of the above methods requires a stepped portion of the housing or a positioning member, which increases the number of steps and the number of members. Further, by providing such a stepped portion or positioning member on the inner periphery of the housing, the radial dimension of the flange portion is reduced as compared with the case where they are not provided, so that the thrust bearing surface formed on the flange portion can be reduced. The area is reduced, and the load capacity in the thrust direction is reduced.

本発明の課題は、スラスト方向の負荷能力を低下させることなく、スラスト軸受隙間を低コストに形成することができる動圧軸受装置及びその製造方法を提供することにある。   An object of the present invention is to provide a hydrodynamic bearing device capable of forming a thrust bearing gap at a low cost without reducing the load capacity in the thrust direction, and a manufacturing method thereof.

前記課題を解決するために、本発明は、側部および底部を有するハウジングと、ハウジングの内周に設けられたスリーブ部と、軸部及びフランジ部を有する軸部材と、スリーブ部の内周面と軸部の外周面との間に形成されたラジアル軸受隙間と、フランジ部の両端面に面する二つのスラスト軸受隙間とを備え、各軸受隙間に生じる潤滑流体の動圧作用で軸部材をラジアル方向及びスラスト方向に支持する動圧軸受装置を製造するための方法であって、両スラスト軸受隙間を０にした状態で、ハウジング側部を軸方向に塑性変形させて両スラスト軸受隙間を形成することを特徴とする。   In order to solve the above-described problems, the present invention provides a housing having side portions and a bottom portion, a sleeve portion provided on the inner periphery of the housing, a shaft member having a shaft portion and a flange portion, and an inner peripheral surface of the sleeve portion. And a radial bearing gap formed between the outer peripheral surface of the shaft part and two thrust bearing gaps facing both end faces of the flange part, and the shaft member is moved by the dynamic pressure action of the lubricating fluid generated in each bearing gap. A method for manufacturing a hydrodynamic bearing device that supports in a radial direction and a thrust direction, wherein both thrust bearing gaps are set to zero, and the housing side portion is plastically deformed in the axial direction to form both thrust bearing gaps. It is characterized by doing.

このように、本発明の動圧軸受装置の製造方法では、まず、ハウジングの内周に軸部材及びスリーブ部を配し、フランジ部の一方の端面をスリーブ部の端面に接触させると共に、フランジ部の他方の端面をハウジング底部の軸受内部側端面に接触させて、両スラスト軸受隙間を０の状態とする。そして、ハウジング及びスリーブ部を互いに不動の状態とした後、ハウジング側部を軸方向に塑性変形させ、両スラスト軸受隙間を形成する。これにより、位置決め用の段部や位置決め部材を要することなく両スラスト軸受隙間を形成することができるため、部材数の削減及び製造コストの低減を図ることができる。   Thus, in the method for manufacturing a hydrodynamic bearing device of the present invention, first, the shaft member and the sleeve portion are arranged on the inner periphery of the housing, and one end surface of the flange portion is brought into contact with the end surface of the sleeve portion, and the flange portion The other end face is brought into contact with the bearing inner end face at the bottom of the housing so that the thrust bearing gap is zero. Then, after making the housing and the sleeve portion immovable, the side portions of the housing are plastically deformed in the axial direction to form both thrust bearing gaps. As a result, both thrust bearing gaps can be formed without the need for positioning steps or positioning members, and therefore the number of members and the manufacturing cost can be reduced.

ところで、ハウジング側部の外周面を塑性変形させる場合、例えば図１２に示すように塑性変形領域（凹部７ａ２０の形成領域）が軸部材２のフランジ部２ｂの外径側まで達すると、ハウジング側部７ａが内径側に突出し、この突出部７ａ１０がフランジ部２ｂと干渉する恐れがある。また、ハウジング側部７ａの塑性変形が突出部７ａ１０の形成に費やされ、ハウジング側部７ａが軸方向に延びず、スラスト軸受隙間の幅設定ができない恐れがある。従って、ハウジング側部を塑性変形させる際には、フランジ部の端面に面したスリーブ部の端面よりもスリーブ部側でハウジングの側部外周面を加圧することが望ましい。   When the outer peripheral surface of the housing side portion is plastically deformed, for example, as shown in FIG. 12, when the plastic deformation region (the formation region of the recess 7a20) reaches the outer diameter side of the flange portion 2b of the shaft member 2, the housing side portion 7a protrudes to the inner diameter side, and this protruding portion 7a10 may interfere with the flange portion 2b. Further, the plastic deformation of the housing side portion 7a is expended in forming the protruding portion 7a10, and the housing side portion 7a does not extend in the axial direction, and there is a possibility that the width of the thrust bearing gap cannot be set. Therefore, when the housing side portion is plastically deformed, it is desirable to pressurize the side outer peripheral surface of the housing closer to the sleeve portion than to the end surface of the sleeve portion facing the end surface of the flange portion.

一方、図１３に示すように、スリーブ部８の一方の端面８ｃからハウジング開口部側に大きく離れた領域を加圧した場合、この加圧領域（凹部７ａ２０形成領域）の周辺においてハウジング側部７ａはスリーブ部８に固定されているため、塑性変形によるハウジング側部７ａの軸方向の延びが規制され、スラスト軸受隙間の幅設定ができない恐れがある。その上、塑性変形による材料の塑性流動により凹部７ａ２０の軸方向両側に***部７ａ２２が形成されるため、ハウジング側部７ａを他部材への組み込み時に支障を来たす恐れがある。また、図１４に示すように、ハウジング側部７ａとスリーブ部８とが軸受部材１７として一体に形成される場合、上記のような場所に凹部７ａ２０を形成すると、材料の塑性流動がスリーブ部８側に拡散するため、ハウジング側部７ａを軸方向に延ばすことができず、やはりスラスト軸受隙間の幅設定を行うことができない。従って、フランジ部の端面に面するスリーブ部の端面に近接した位置、具体的には、スリーブ部の前記端面の外周チャンファと対向した位置を加圧することが望ましい。   On the other hand, as shown in FIG. 13, when a region greatly separated from the one end face 8c of the sleeve portion 8 toward the housing opening is pressurized, the housing side portion 7a is formed around the pressure region (recess 7a20 formation region). Is fixed to the sleeve portion 8, the axial extension of the housing side portion 7a due to plastic deformation is restricted, and the width of the thrust bearing gap may not be set. In addition, since the raised portions 7a22 are formed on both sides in the axial direction of the concave portion 7a20 due to plastic flow of the material due to plastic deformation, there is a possibility that the housing side portion 7a may be hindered when assembled into another member. As shown in FIG. 14, when the housing side portion 7 a and the sleeve portion 8 are integrally formed as the bearing member 17, if the concave portion 7 a 20 is formed in the place as described above, the plastic flow of the material causes the sleeve portion 8. Therefore, the housing side portion 7a cannot be extended in the axial direction, and the width of the thrust bearing gap cannot be set. Therefore, it is desirable to pressurize a position close to the end face of the sleeve part facing the end face of the flange part, specifically, a position facing the outer peripheral chamfer of the end face of the sleeve part.

このような方法でスラスト軸受隙間を形成するに際し、ハウジング底部の軸方向変位を検知しながらハウジングを軸方向に塑性変形させると、スラスト軸受隙間の隙間幅を精度良く管理することができる。   When forming the thrust bearing gap by such a method, if the housing is plastically deformed in the axial direction while detecting the axial displacement of the housing bottom, the gap width of the thrust bearing gap can be managed with high accuracy.

また、両スラスト軸受隙間をハウジングの軸方向の塑性変形で形成した動圧軸受装置は、スラスト軸受隙間の隙間幅設定用の段部や位置決め部材を要さないため、フランジ部の径方向寸法が縮小されることがない。従って、スラスト軸受面の面積を維持することができ、優れたスラスト負荷能力を得ることができる。   In addition, the hydrodynamic bearing device in which both thrust bearing gaps are formed by plastic deformation in the axial direction of the housing does not require a step part or positioning member for setting the gap width of the thrust bearing gap, so the radial dimension of the flange part is There is no reduction. Therefore, the area of the thrust bearing surface can be maintained, and an excellent thrust load capability can be obtained.

また、このような動圧軸受装置において、ハウジングの側部外周面を加圧して塑性変形させ、この塑性変形で形成された凹部を接着剤溜りとして機能させることにより、ハウジング側部をモータブラケット等の他部材に固定する際の固定強度を高めることができる。   Further, in such a dynamic pressure bearing device, the side surface of the housing is pressurized and plastically deformed, and the concave portion formed by the plastic deformation functions as an adhesive reservoir, so that the housing side portion can be used as a motor bracket or the like. The fixing strength at the time of fixing to other members can be increased.

以上のように、本発明によると、スラスト方向の負荷能力を低下させることなく、スラスト軸受隙間を低コストに形成することができる動圧軸受装置及びその製造方法が得られる。   As described above, according to the present invention, it is possible to obtain a hydrodynamic bearing device capable of forming a thrust bearing gap at a low cost without reducing the load capacity in the thrust direction and a method for manufacturing the same.

以下、本発明の実施形態を図面に基づいて説明する。   Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１は、本発明に係る方法で製造した動圧軸受装置１を組込んだ情報機器用スピンドルモータの一構成例を概念的に示している。このスピンドルモータは、ＨＤＤ等のディスク駆動装置に用いられるもので、ディスクハブ３を取付けた軸部材２を回転自在に非接触支持する動圧軸受装置１と、半径方向のギャップを介して対向させたステータコイル４およびロータマグネット５と、モータブラケット６とを備えている。ステータコイル４はモータブラケット６の外周に取付けられ、ロータマグネット５はディスクハブ３の内周に取付けられている。動圧軸受装置１のハウジング７は、モータブラケット６の内周に固定される。ディスクハブ３には、磁気ディスク等のディスク状情報記録媒体（以下、単にディスクという）Ｄが任意の枚数（本実施形態では２枚）保持される。このように構成されたスピンドルモータにおいて、ステータコイル４に通電すると、ステータコイル４とロータマグネット５との間に発生する電磁力でロータマグネット５が回転し、これに伴って、ディスクハブ３およびディスクハブ３に保持されたディスクＤが軸部材２と一体に回転する。   FIG. 1 conceptually shows one configuration example of a spindle motor for information equipment incorporating a fluid dynamic bearing device 1 manufactured by the method according to the present invention. This spindle motor is used in a disk drive device such as an HDD, and is opposed to a hydrodynamic bearing device 1 that rotatably supports a shaft member 2 to which a disk hub 3 is attached via a radial gap. The stator coil 4 and the rotor magnet 5 and the motor bracket 6 are provided. The stator coil 4 is attached to the outer periphery of the motor bracket 6, and the rotor magnet 5 is attached to the inner periphery of the disk hub 3. The housing 7 of the hydrodynamic bearing device 1 is fixed to the inner periphery of the motor bracket 6. The disk hub 3 holds an arbitrary number (two in this embodiment) of a disk-shaped information recording medium (hereinafter simply referred to as a disk) D such as a magnetic disk. In the spindle motor configured as described above, when the stator coil 4 is energized, the rotor magnet 5 is rotated by the electromagnetic force generated between the stator coil 4 and the rotor magnet 5. The disk D held by the hub 3 rotates integrally with the shaft member 2.

図２は、動圧軸受装置１を示している。この動圧軸受装置１は、側部７ａおよび底部７ｂを有するハウジング７と、ハウジング７の内周面７ａ１に固定されたスリーブ部８と、ハウジング７およびスリーブ部８に対して相対回転する軸部材２とを主な構成要素として構成される。なお、説明の便宜上、ハウジング７の底部７ｂの側を下側、開口側を上側として以下説明する。   FIG. 2 shows the hydrodynamic bearing device 1. The hydrodynamic bearing device 1 includes a housing 7 having a side portion 7a and a bottom portion 7b, a sleeve portion 8 fixed to the inner peripheral surface 7a1 of the housing 7, and a shaft member that rotates relative to the housing 7 and the sleeve portion 8. 2 is configured as a main component. For convenience of explanation, the following description will be made with the bottom 7b side of the housing 7 as the lower side and the opening side as the upper side.

軸部材２は、例えばＳＵＳ鋼などの金属材料で形成され、軸部２ａと、軸部２ａの下端に一体又は別体に設けられるフランジ部２ｂとを備える。軸部材の構成はこれに限らず、例えば、金属材料で形成した軸部をインサート部品とした樹脂の射出成形によりフランジ部２ｂを形成してもよい。あるいは、フランジ部２ｂの両端面２ｂ１、２ｂ２のみを樹脂材料で形成してもよい。   The shaft member 2 is formed of, for example, a metal material such as SUS steel, and includes a shaft portion 2a and a flange portion 2b provided integrally or separately at the lower end of the shaft portion 2a. The configuration of the shaft member is not limited to this, and for example, the flange portion 2b may be formed by injection molding of resin using a shaft portion formed of a metal material as an insert part. Or you may form only the both end surfaces 2b1, 2b2 of the flange part 2b with a resin material.

スリーブ部８は、例えば銅を主成分とする焼結金属の多孔質体で円筒状に形成される。この他、スリーブ部８を他の金属や樹脂、あるいはセラミック等で形成することも可能である。   The sleeve portion 8 is formed in a cylindrical shape, for example, from a sintered metal porous body mainly composed of copper. In addition, the sleeve portion 8 can be formed of another metal, resin, ceramic, or the like.

スリーブ部８の内周面８ａの全面又は一部円筒領域には、ラジアル動圧発生部として、例えば図３（ａ）に示すように、複数の動圧溝８ａ１、８ａ２をヘリングボーン形状に配列した領域が軸方向に離隔して２箇所形成される。上側の動圧溝８ａ１は軸方向非対称形状に形成され、具体的には、動圧溝８ａ１の軸方向中間部に形成された環状の平滑部より上側の溝の軸方向寸法Ｘ１が下側の溝の軸方向寸法Ｘ２よりも大きくなっている（Ｘ１＞Ｘ２）。   As shown in FIG. 3A, for example, as shown in FIG. 3A, a plurality of dynamic pressure grooves 8a1 and 8a2 are arranged in a herringbone shape on the entire inner surface 8a of the sleeve portion 8 or a partial cylindrical region. The two regions are formed at two positions apart in the axial direction. The upper dynamic pressure groove 8a1 is formed in an axially asymmetric shape. Specifically, the axial dimension X1 of the upper groove is lower than the annular smooth portion formed in the axial intermediate portion of the dynamic pressure groove 8a1. It is larger than the axial dimension X2 of the groove (X1> X2).

スリーブ部８の外周面８ｄには、軸方向に延びる溝８ｄ１が軸方向全長に亘って任意の本数形成される。この実施形態では、３本の軸方向溝８ｄ１を円周方向等間隔に形成している。これら軸方向溝８ｄ１は、スリーブ部８をハウジング７の内周に固定した状態では、対向するハウジング７の内周面７ａ１との間に潤滑油の流体流路を構成する（図２を参照）。これら軸方向溝８ｄ１は、例えばスリーブ部８本体をなす圧粉体の成形型に予め軸方向溝８ｄ１に対応する箇所を設けておくことで、スリーブ部８本体の圧粉体成形と同時に成形することができる。   An arbitrary number of grooves 8d1 extending in the axial direction are formed on the outer peripheral surface 8d of the sleeve portion 8 over the entire length in the axial direction. In this embodiment, three axial grooves 8d1 are formed at equal intervals in the circumferential direction. These axial grooves 8d1 constitute a fluid flow path for lubricating oil between the inner peripheral surface 7a1 of the housing 7 facing the sleeve 7 in a state where the sleeve portion 8 is fixed to the inner periphery of the housing 7 (see FIG. 2). . These axial grooves 8d1 are formed at the same time as the green compact forming of the sleeve portion 8 main body by, for example, providing a portion corresponding to the axial groove 8d1 in advance in the green compact forming die forming the main body of the sleeve portion 8. be able to.

スリーブ部８の下側端面８ｃの全面または一部環状領域には、スラスト動圧発生部として、図３（ｂ）に示すように、複数の動圧溝８ｃ１をスパイラル形状に配列した領域が形成される。   As shown in FIG. 3B, a region where a plurality of dynamic pressure grooves 8c1 are arranged in a spiral shape is formed as a thrust dynamic pressure generating portion on the entire lower surface 8c of the sleeve portion 8 or a partial annular region. Is done.

スリーブ部８の上側端面８ｂの径方向の略中央部には、図３（ａ）に示すように、Ｖ字断面の周方向溝８ｂ１が全周に亘って形成される。周方向溝８ｂ１によって区画された上側端面８ｂの内径側領域には、任意の本数の半径方向溝８ｂ２が形成される。この半径方向溝８ｂ２は、スリーブ部８にシール部９を当接させた状態で、周方向溝８ｂ１とラジアル軸受隙間との間を連通する（図２参照）。   As shown in FIG. 3A, a circumferential groove 8b1 having a V-shaped cross section is formed over the entire circumference at a substantially central portion in the radial direction of the upper end surface 8b of the sleeve portion 8. An arbitrary number of radial grooves 8b2 are formed in the inner diameter side region of the upper end face 8b defined by the circumferential grooves 8b1. The radial groove 8b2 communicates between the circumferential groove 8b1 and the radial bearing gap in a state where the seal portion 9 is in contact with the sleeve portion 8 (see FIG. 2).

ハウジング７は金属材料で形成され、例えば真ちゅう等の軟質金属のプレス加工により形成される。この他、金属材料の機械加工や、金属紛とバインダーの混合物で射出成形した後、脱脂・焼結するいわゆるＭＩＭ成形によりハウジング７を形成することもできる。あるいは、金属材料に限らず、樹脂材料でハウジング７を形成することもできる。   The housing 7 is made of a metal material, and is formed by pressing a soft metal such as brass. In addition, the housing 7 may be formed by so-called MIM molding in which a metal material is machined or injection molded with a mixture of metal powder and a binder and then degreased and sintered. Or the housing 7 can also be formed not only with a metal material but with a resin material.

ハウジング底部７ｂの上側端面７ｂ１の全面又は一部環状領域には、図４に示すように、スラスト動圧発生部として、複数の動圧溝７ｂ１１をスパイラル形状に配列した領域が形成される。また、ハウジング７の内周面７ａ１には、スリーブ部８の外周面８ｄが、例えば接着（ルーズ接着や圧入接着を含む）、圧入、溶着等の適宜の手段で固定される。   As shown in FIG. 4, a region where a plurality of dynamic pressure grooves 7b11 are arranged in a spiral shape is formed as a thrust dynamic pressure generating portion on the entire surface or a partial annular region of the upper end surface 7b1 of the housing bottom 7b. Further, the outer peripheral surface 8d of the sleeve portion 8 is fixed to the inner peripheral surface 7a1 of the housing 7 by an appropriate means such as bonding (including loose bonding or press-fitting bonding), press-fitting, or welding.

ハウジング７の側部７ａの外周面７ａ２には、環状の凹部７ａ２０が形成される。この凹部７ａ２０が接着剤溜りとして機能することにより、ハウジング７とブラケット６（図１参照）との固定強度を高めることができる。   An annular recess 7 a 20 is formed on the outer peripheral surface 7 a 2 of the side portion 7 a of the housing 7. When the recess 7a20 functions as an adhesive reservoir, the fixing strength between the housing 7 and the bracket 6 (see FIG. 1) can be increased.

シール部９は、図２に示すように、例えば金属材料や樹脂材料でハウジング７とは別体に形成され、ハウジング７の側部７ａの上端部内周に圧入、接着、溶着、溶接等の手段で固定される。シール部９の固定は、シール部９の下側端面９ｂをスリーブ部８の上側端面８ｂに当接させた状態で行われる。   As shown in FIG. 2, the seal portion 9 is formed of a metal material or a resin material separately from the housing 7, for example, press fitting, bonding, welding, welding, or the like on the inner periphery of the upper end of the side portion 7 a of the housing 7 It is fixed with. The sealing portion 9 is fixed in a state where the lower end surface 9 b of the sealing portion 9 is in contact with the upper end surface 8 b of the sleeve portion 8.

シール部９の内周面９ａにはテーパ面が形成されており、このテーパ面と、テーパ面に対向する軸部２ａの外周面２ａ１との間には、上方に向けて半径方向寸法が漸次拡大する環状のシール空間Ｓが形成される。シール部９で密封されたハウジング７の内部空間には、潤滑油が注油され、ハウジング７内が潤滑油で満たされる（図２中の散点領域）。この状態では、潤滑油の油面はシール空間Ｓの範囲内に維持される。   A taper surface is formed on the inner peripheral surface 9a of the seal portion 9, and the radial dimension gradually increases between the taper surface and the outer peripheral surface 2a1 of the shaft portion 2a facing the taper surface. An expanding annular seal space S is formed. Lubricating oil is injected into the internal space of the housing 7 sealed by the seal portion 9, and the inside of the housing 7 is filled with the lubricating oil (a dotted area in FIG. 2). In this state, the oil level of the lubricating oil is maintained within the range of the seal space S.

上記構成の動圧軸受装置１において、軸部材２の回転時、スリーブ部８のラジアル軸受面（内周面８ａの動圧溝８ａ１、８ａ２形成領域）は、軸部２ａの外周面２ａ１とラジアル軸受隙間を介して対向する。軸部材２の回転に伴い、上記ラジアル軸受隙間の潤滑油が動圧溝８ａ１、８ａ２のそれぞれの軸方向中央側に押し込まれ、その圧力が上昇する。このような動圧溝８ａ１、８ａ２の動圧作用によって、軸部材２をラジアル方向に非接触支持する第１ラジアル軸受部Ｒ１と第２ラジアル軸受部Ｒ２とが構成される。   In the dynamic pressure bearing device 1 configured as described above, when the shaft member 2 rotates, the radial bearing surface of the sleeve portion 8 (the region where the dynamic pressure grooves 8a1 and 8a2 are formed on the inner peripheral surface 8a) is radial with the outer peripheral surface 2a1 of the shaft portion 2a. Opposing through the bearing gap. As the shaft member 2 rotates, the lubricating oil in the radial bearing gap is pushed into the axially central sides of the dynamic pressure grooves 8a1 and 8a2, and the pressure rises. By such dynamic pressure action of the dynamic pressure grooves 8a1 and 8a2, the first radial bearing portion R1 and the second radial bearing portion R2 that support the shaft member 2 in a non-contact manner in the radial direction are configured.

これと同時に、スリーブ部８のスラスト軸受面（下側端面８ｃの動圧溝８ｃ１形成領域）とこれに対向するフランジ部２ｂの上側端面２ｂ１との間の第１スラスト軸受隙間、およびハウジング７のスラスト軸受面（ハウジング底部７ｂの上側端面７ｂ１の動圧溝７ｂ１１形成領域）とこれに対向するフランジ部２ｂの下側端面２ｂ２との間の第２スラスト軸受隙間に、各動圧溝の動圧作用により潤滑油の油膜がそれぞれ形成される。そして、これら油膜の圧力によって、軸部材２をスラスト方向に非接触支持する第１スラスト軸受部Ｔ１と、第２スラスト軸受部Ｔ２とが構成される。   At the same time, the first thrust bearing gap between the thrust bearing surface of the sleeve portion 8 (the region where the dynamic pressure groove 8c1 is formed on the lower end surface 8c) and the upper end surface 2b1 of the flange portion 2b facing this, and the housing 7 The dynamic pressure of each dynamic pressure groove is provided in the second thrust bearing gap between the thrust bearing surface (the region where the dynamic pressure groove 7b11 is formed on the upper end surface 7b1 of the housing bottom 7b) and the lower end surface 2b2 of the flange portion 2b facing this. An oil film of lubricating oil is formed by the action. The pressure of these oil films forms a first thrust bearing portion T1 and a second thrust bearing portion T2 that support the shaft member 2 in a non-contact manner in the thrust direction.

また、ハウジング７の閉塞側に位置する第１及び第２スラスト軸受隙間と、ハウジング７の開口側に形成されるシール空間Ｓとの間が、軸方向溝８ｄ１や半径方向溝８ｂ２等を介して連通状態となる。これによれば、例えば何らかの理由でスラスト軸受部Ｔ１、Ｔ２の側の流体（潤滑油）圧力が過度に高まり、あるいは低下するといった事態を避けて、軸部材２をスラスト方向に安定して非接触支持することが可能となる。   Further, the gap between the first and second thrust bearing gaps located on the closed side of the housing 7 and the seal space S formed on the opening side of the housing 7 is interposed via the axial groove 8d1 and the radial groove 8b2. It becomes a communication state. According to this, for example, the shaft (2) is stably non-contacted in the thrust direction while avoiding a situation in which the fluid (lubricating oil) pressure on the thrust bearing portions T1, T2 side is excessively increased or decreased for some reason. It becomes possible to support.

また、この実施形態では、第１ラジアル軸受部Ｒ１の動圧溝８ａ１が軸方向非対称（Ｘ１＞Ｘ２）に形成されているため（図３参照）、軸部材２の回転時、動圧溝８ａ１の上側の溝による潤滑油の引き込み力（ポンピング力）は、下側の溝の引き込み力に比べて相対的に大きくなる。そして、この引き込み力の差圧によって、スリーブ部８の内周面８ａと軸部２ａの外周面２ａ１との間の隙間に満たされた潤滑油が下方に流動し、第１スラスト軸受隙間→軸方向溝８ｄ１→シール部９の下側端面９ｂとスリーブ部８の上側端面８ｂとの間の隙間→円周方向溝８ｂ１→半径方向溝８ｂ２という経路を循環して、第１ラジアル軸受部Ｒ１のラジアル軸受隙間に再び引き込まれる。このように、潤滑油がハウジング７の内部空間を流動循環するように構成することで、軸受内部の圧力バランスが適正に保たれる。これにより、潤滑油の負圧発生に伴う気泡の生成を防止し、これに伴う潤滑油の漏れや振動の発生等の問題を解消することができる。   In this embodiment, since the dynamic pressure groove 8a1 of the first radial bearing portion R1 is formed to be axially asymmetric (X1> X2) (see FIG. 3), the dynamic pressure groove 8a1 is rotated when the shaft member 2 is rotated. The pulling force (pumping force) of the lubricating oil by the upper groove is relatively larger than the pulling force of the lower groove. Then, due to the differential pressure of the pulling force, the lubricating oil filled in the gap between the inner peripheral surface 8a of the sleeve portion 8 and the outer peripheral surface 2a1 of the shaft portion 2a flows downward, and the first thrust bearing gap → shaft The first radial bearing portion R1 is circulated through the path of the direction groove 8d1 → the clearance between the lower end surface 9b of the seal portion 9 and the upper end surface 8b of the sleeve portion 8 → the circumferential groove 8b1 → the radial groove 8b2. It is pulled back into the radial bearing gap. In this way, by configuring the lubricating oil to flow and circulate in the internal space of the housing 7, the pressure balance inside the bearing is properly maintained. Thereby, generation | occurrence | production of the bubble accompanying the negative pressure generation | occurrence | production of lubricating oil can be prevented, and problems, such as the leakage of the lubricating oil accompanying this and generation | occurrence | production of a vibration, can be eliminated.

以上のような構成を有する動圧軸受装置１の組立方法、特にスラスト軸受隙間の設定方法の一例を、図５〜図８に基づいて説明する。   An example of a method for assembling the hydrodynamic bearing device 1 having the above-described configuration, in particular, a method for setting a thrust bearing gap will be described with reference to FIGS.

まず、ハウジング７の内周に軸部材２及びスリーブ部８を収容し、軸部材２のフランジ部２ｂの下側端面２ｂ２をハウジング底部７ｂの上側端面７ｂ１に接触させると共に、フランジ部２ｂの上側端面２ｂ１をスリーブ部８の下側端面８ｃに接触させ、第１及び第２スラスト軸受隙間の隙間幅を０の状態とする。この状態で、ハウジング側部７ａの内周面７ａ１にスリーブ部８の外周面８ｄを固定し、ハウジング７及びスリーブ部８を互いに不動の状態としたサブアッシ品１０を形成する（図６（ａ）参照）。例えば、ハウジング７とスリーブ部８とを接着固定する場合、これらの固定面に熱硬化性接着剤を介在させ、上記の状態で熱処理（ベーキング）することにより、両部材が固定される。   First, the shaft member 2 and the sleeve portion 8 are accommodated in the inner periphery of the housing 7, the lower end surface 2b2 of the flange portion 2b of the shaft member 2 is brought into contact with the upper end surface 7b1 of the housing bottom portion 7b, and the upper end surface of the flange portion 2b. 2b1 is brought into contact with the lower end surface 8c of the sleeve portion 8 so that the gap width between the first and second thrust bearing gaps is zero. In this state, the outer peripheral surface 8d of the sleeve portion 8 is fixed to the inner peripheral surface 7a1 of the housing side portion 7a, thereby forming the sub-assembly product 10 in which the housing 7 and the sleeve portion 8 are immovable (FIG. 6A). reference). For example, when the housing 7 and the sleeve portion 8 are bonded and fixed, both members are fixed by interposing a thermosetting adhesive on these fixing surfaces and performing heat treatment (baking) in the above state.

次に、ハウジング側部７ａを塑性変形させることによりスラスト軸受隙間を形成する。この塑性変形は、例えば図５に示すような装置を用いたローリング加工で行うことができる。この装置は、ローラ１１、ローラ１２、及びローリング治具１３を備え、ローラ１１、１２は回転軸が平行となるように配される。このローラ１１及び１２の上にサブアッシ品１０を載置し、ローリング治具１３をハウジング７の外周面７ａ２に接触させながら、ローラ１１及び１２を回転駆動する。これにより、サブアッシ品１０を回転させながら、ハウジング側部７ａの外周面７ａ２の一部環状領域をローリング治具１３で圧迫して塑性変形させる。尚、サブアッシ品１０の回転は、ローラ１１及び１２を回転駆動させる方法に限らず、これらの何れか一方を回転駆動する方法や、ローラ１１及び１２を駆動せず、ローリング治具１３を回転駆動する方法など、任意の方法を採用することができる。   Next, a thrust bearing gap is formed by plastically deforming the housing side portion 7a. This plastic deformation can be performed by rolling using an apparatus as shown in FIG. 5, for example. This apparatus includes a roller 11, a roller 12, and a rolling jig 13, and the rollers 11 and 12 are arranged so that their rotation axes are parallel to each other. The sub-assemblies 10 are placed on the rollers 11 and 12, and the rollers 11 and 12 are rotated while the rolling jig 13 is in contact with the outer peripheral surface 7a2 of the housing 7. As a result, while rotating the sub-assembly product 10, the partial annular region of the outer peripheral surface 7 a 2 of the housing side portion 7 a is pressed by the rolling jig 13 to be plastically deformed. The rotation of the subassembly 10 is not limited to the method of rotating the rollers 11 and 12, but the method of rotating any one of them, or the roller 11 and 12 is not driven, and the rolling jig 13 is rotated. Arbitrary methods, such as a method to do, can be adopted.

ハウジング７の外周面７ａ２の塑性変形の詳細を図６及び図７に示す。尚、図６及び図７では、図中右側が下方、図中左側が上方となる。まず、サブアッシ品１０を回転させた状態で、ハウジング７の外径側からローリング治具１３のローラ１３ａを接触させ、ハウジング７の外周面７ａ２を圧迫する（図６（ａ）参照）。これにより、ハウジング７の外周面７ａ２の一部環状領域が塑性変形し、環状の凹部７ａ２０が形成されると共に、ハウジング７の材料の塑性流動によりハウジング側部７ａが軸方向に延びる（図６（ｂ）参照）。このとき、ハウジング底部７ｂの下側端面７ｂ２の軸方向の移動量をセンサ１４で測りながらローリング加工を行うことにより、ハウジング側部７ａの軸方向の延び量δを管理することができる。この延び量δが、第１及び第２スラスト軸受隙間の隙間幅の合計量の設定値と等しくなったとき、ローリング加工を終了する。尚、図６（ｂ）において、凹部７ａ２０の深さやハウジング側部７ａの軸方向の延び量δは、理解しやすいように誇張して示している。   Details of plastic deformation of the outer peripheral surface 7a2 of the housing 7 are shown in FIGS. 6 and 7, the right side in the figure is the lower side and the left side in the figure is the upper side. First, in a state where the sub-assembly product 10 is rotated, the roller 13a of the rolling jig 13 is brought into contact with the outer diameter side of the housing 7 to press the outer peripheral surface 7a2 of the housing 7 (see FIG. 6A). Thereby, a partial annular region of the outer peripheral surface 7a2 of the housing 7 is plastically deformed to form an annular recess 7a20, and the housing side portion 7a extends in the axial direction due to plastic flow of the material of the housing 7 (FIG. 6 ( b)). At this time, the axial extension amount δ of the housing side portion 7a can be managed by performing rolling while measuring the amount of axial movement of the lower end surface 7b2 of the housing bottom portion 7b with the sensor 14. When the extension amount δ becomes equal to the set value of the total amount of the gap widths of the first and second thrust bearing gaps, the rolling process is finished. In FIG. 6B, the depth of the recess 7a20 and the axial extension δ of the housing side portion 7a are exaggerated for easy understanding.

このとき、ハウジング側部７ａが内径側に変形する不具合（図１２参照）を回避するため、スリーブ部８の下側端面８ｃよりも上側でハウジング側部７ａを加圧することが望ましい。また、ハウジング側部７ａの延びが生じない不具合（図１３参照）を回避するため、スリーブ部８の下側端面８ｃに近接した領域を加圧することが好ましい。すなわち、理想的には、図６（ａ）に示すように、ローリング治具１３による加圧領域のハウジング底部７ｂ側の端部を、ハウジング７とスリーブ部８との固定面の下端部Ａと軸方向で一致させることが好ましい。しかし、これらを軸方向で完全に一致させることは現実的に困難であるため、例えば図７で示すように、スリーブ部８の下側端面８ｃの軸方向位置Ｂのよりも上側で、且つ、スリーブ部８の下側端面８ｃの外周チャンファ８ｃ２と対向する部分を含む領域を圧迫すればよい。この圧迫領域のうち、外周チャンファ８ｃ２と対向する領域では、ハウジング側部７ａが内径側に変形する場合があるが、この変形領域の内径側はスリーブ部８のチャンファ８ｃ２であるため、軸部材２のフランジ部２ｂと干渉する恐れはない。 At this time, it is desirable to pressurize the housing side portion 7a above the lower end surface 8c of the sleeve portion 8 in order to avoid a problem that the housing side portion 7a is deformed to the inner diameter side (see FIG. 12). Moreover, in order to avoid the malfunction (refer FIG. 13) which the housing side part 7a does not produce, it is preferable to pressurize the area | region close to the lower end surface 8c of the sleeve part 8. FIG. That is, ideally, as shown in FIG. 6A, the end of the pressurization region on the housing bottom 7 b side by the rolling jig 13 is the lower end A of the fixing surface of the housing 7 and the sleeve 8. It is preferable to match in the axial direction. However, since it is practically difficult to completely match these in the axial direction, for example, as shown in FIG. 7, above the axial position B of the lower end surface 8 c of the sleeve portion 8, and What is necessary is just to compress the area | region including the part which opposes the outer peripheral chamfer 8c2 of the lower end surface 8c of the sleeve part 8. FIG. Among the compression regions, in the region facing the outer peripheral chamfer 8c2, the housing side portion 7a may be deformed to the inner diameter side. Since the inner diameter side of the deformation region is the chamfer 8c2 of the sleeve portion 8, the shaft member 2 There is no possibility of interference with the flange portion 2b.

あるいは、図８に示すように、凹部７ａ２０を軸方向位置Ａよりも若干ハウジング開口部側に設けても良い。このとき、ハウジング側部７ａの肉厚をｔとし、軸方向位置Ａと凹部７ａ２０の下端部の軸方向位置Ｃとの距離をｄとしたとき、ｄ≦ｔであることが好ましい。これにより、ハウジング側部７ａの変形による材料の塑性流動が、ハウジング側部７ａのうちスリーブ部８に固定されていない領域、すなわち軸方向位置Ａの下側まで確実に達し、ハウジング側部７ａが軸方向に延びて両スラスト軸受隙間を形成すことができる。   Alternatively, as shown in FIG. 8, the recess 7 a 20 may be provided slightly closer to the housing opening than the axial position A. At this time, it is preferable that d ≦ t, where t is the thickness of the housing side 7a and d is the distance between the axial position A and the axial position C of the lower end of the recess 7a20. Thereby, the plastic flow of the material due to the deformation of the housing side portion 7a reliably reaches the region of the housing side portion 7a that is not fixed to the sleeve portion 8, that is, the lower side of the axial position A. Both thrust bearing gaps can be formed by extending in the axial direction.

ところで、上記のようにしてスラスト軸受隙間を形成するに際し、ハウジング側部７ａの軸方向の延び量を円周方向で完全に一致させることは困難である。ハウジング側部７ａの延び量が円周方向で異なると、第２スラスト軸受隙間に面するハウジング底部の面精度が低下し、スラスト方向の負荷能力が低下する恐れがある。この点に鑑み、図６（ａ）の矢印で示すように、軸部材２のフランジ部２ｂの下側端面２ｂ２をハウジング底部７ｂの上側端面７ｂ１に押し付けながらハウジング側部７ａを塑性変形させれば、ハウジング底部７ｂの上側端面７ｂ１の面精度を維持しながら両スラスト軸受隙間を形成することができる。   By the way, when the thrust bearing gap is formed as described above, it is difficult to completely match the axial extension amount of the housing side portion 7a in the circumferential direction. If the extension amount of the housing side portion 7a is different in the circumferential direction, the surface accuracy of the housing bottom portion facing the second thrust bearing gap may be reduced, and the load capacity in the thrust direction may be reduced. In view of this point, if the housing side portion 7a is plastically deformed while pressing the lower end surface 2b2 of the flange portion 2b of the shaft member 2 against the upper end surface 7b1 of the housing bottom portion 7b, as indicated by an arrow in FIG. Both thrust bearing gaps can be formed while maintaining the surface accuracy of the upper end surface 7b1 of the housing bottom 7b.

本発明に係る製造方法は、上記の実施形態に限られない。以下、本発明の他の実施形態を説明する。尚、以下の説明において、上記の実施形態と同一の構成・機能を有する箇所には同一の符号を付して説明を省略する。   The manufacturing method according to the present invention is not limited to the above embodiment. Hereinafter, other embodiments of the present invention will be described. In the following description, portions having the same configuration and function as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

上記の実施形態では、ハウジング側部７ａの外周面７ａ２の一部に凹部７ａ２０を形成する場合を示しているが、これに限られない。例えば、図９（ａ）に示すように、ハウジング側部７ａの外周面７ａ２の軸方向一部領域に予め大径部７ａ２３を形成し、この大径部７ａ２３を潰してハウジング側部７ａを軸方向に塑性変形させることにより、スラスト軸受隙間を形成することができる。具体的には、ハウジング側部７ａの外径側からローリング治具１３で大径部７ａ２３を圧迫して潰し、これによる材料の塑性流動でハウジング側部７ａを軸方向に延ばす。このときのハウジング側部７ａの延び量δが第１及び第２スラスト軸受隙間の隙間幅の合計量と等しくなったときに、ローリング加工を終了する（図９（ｂ）参照）。この場合、ローリング治具１３のローラ１３ａの軸方向幅を大径部７ａ２３の軸方向寸法よりも大きくしておくと、大径部７ａ２３の圧迫を容易に行うことができる。また、ハウジング側部７ａの延び量δは、予め大径部７ａ２３の突出量ｈを規定量に設定することで管理しても良いし、あるいは、図６（ｂ）と同様に、ハウジング底部７ｂの移動量をセンサで測定することにより管理してもよい。前者の方法では、大径部７ａ２３を完全に潰すことになるため、ローリング加工終了後のハウジング側部７ａの外周面７ａ２を円筒面とすることができる。また、後者の方法では、大径部７ａ２３の突出量の形成誤差に左右されることなく、スラスト軸受隙間の幅設定を行うことができる。この場合、大径部７ａ２３は完全に潰されることはなく、ハウジング側部７ａの外周面７ａ２に大径部痕が残ることとなる（図示省略）。   In the above embodiment, the case where the concave portion 7a20 is formed in a part of the outer peripheral surface 7a2 of the housing side portion 7a is shown, but the present invention is not limited to this. For example, as shown in FIG. 9A, a large-diameter portion 7a23 is formed in advance in a partial axial region of the outer peripheral surface 7a2 of the housing side portion 7a, and the large-diameter portion 7a23 is crushed so that the housing side portion 7a is pivoted. A thrust bearing gap can be formed by plastic deformation in the direction. Specifically, the large-diameter portion 7a23 is pressed and crushed by the rolling jig 13 from the outer diameter side of the housing side portion 7a, and the housing side portion 7a is extended in the axial direction by plastic flow of the material. When the extension amount δ of the housing side portion 7a at this time becomes equal to the total amount of the gap widths of the first and second thrust bearing gaps, the rolling process is finished (see FIG. 9B). In this case, if the axial width of the roller 13a of the rolling jig 13 is made larger than the axial dimension of the large diameter portion 7a23, the large diameter portion 7a23 can be easily compressed. Further, the extension amount δ of the housing side portion 7a may be managed by setting the protruding amount h of the large-diameter portion 7a23 to a specified amount in advance, or, similarly to FIG. 6B, the housing bottom portion 7b. The amount of movement may be managed by measuring with a sensor. In the former method, since the large-diameter portion 7a23 is completely crushed, the outer peripheral surface 7a2 of the housing side portion 7a after the rolling process can be made cylindrical. In the latter method, the width of the thrust bearing gap can be set without being influenced by the formation error of the protrusion amount of the large diameter portion 7a23. In this case, the large-diameter portion 7a23 is not completely crushed, and a large-diameter portion trace remains on the outer peripheral surface 7a2 of the housing side portion 7a (not shown).

以上の実施形態では、ハウジング側部７ａとスリーブ部８とが別体に形成される場合を示しているが、これに限らず、例えば図１０に示すように、これらを軸受部材１７として一体に形成してもよい。このとき、ハウジング底部７ｂは別体に形成され、軸受部材１７の下側の大径内周面、すなわち上記実施形態で言うハウジング側部７ａの内周面７ａ１の下端部に圧入や接着等の適宜の方法で固定される。また、軸受部材１７のうち、スリーブ部８の外径端にはスリーブ部８の両端面８ｂ及び８ｃに開口した貫通孔１７ａが形成され、スリーブ部８の上側端面８ｂには径方向溝１７ｂが形成される。これら貫通孔１７ａ及び径方向溝１７ｂにより、第１スラスト軸受隙間の外径端とラジアル軸受隙間の上端とが連通状態となる。   In the above embodiment, the case where the housing side portion 7a and the sleeve portion 8 are formed separately is shown. However, the present invention is not limited to this, and for example, as shown in FIG. It may be formed. At this time, the housing bottom 7b is formed as a separate body, and is press-fitted, bonded, or the like to the lower-diameter inner peripheral surface on the lower side of the bearing member 17, that is, the lower end portion of the inner peripheral surface 7a1 of the housing side portion 7a referred to in the above embodiment. It is fixed by an appropriate method. Further, in the bearing member 17, through-holes 17 a that are open to both end surfaces 8 b and 8 c of the sleeve portion 8 are formed at the outer diameter end of the sleeve portion 8, and a radial groove 17 b is formed on the upper end surface 8 b of the sleeve portion 8. It is formed. The through hole 17a and the radial groove 17b allow the outer diameter end of the first thrust bearing gap and the upper end of the radial bearing gap to be in communication with each other.

このような動圧軸受装置の組み立ては、次のようにして行われる。まず、軸受部材１７のスリーブ部８の内周に軸部材２を挿入する。その後、軸受部材１７の下側の大径内周面７ａ１にハウジング底部７ｂを嵌合し、軸部材２のフランジ部２ｂの上側端面２ｂ１にスリーブ部８の下側端面８ｃを接触させると共に、フランジ部２ｂの下側端面２ｂ２にハウジング底部７ｂの上側端面７ｂ１を接触させ、両スラスト軸受隙間を０の状態とする。そして、ハウジング底部７ｂをハウジング側部７ａの内周面７ａ１に固定して、ハウジング７及びスリーブ部８を互いに不動の状態とする。その後の両スラスト軸受隙間の形成方法は、上記の実施形態と同様であるため説明を省略する。   The assembly of such a hydrodynamic bearing device is performed as follows. First, the shaft member 2 is inserted into the inner periphery of the sleeve portion 8 of the bearing member 17. Thereafter, the housing bottom portion 7b is fitted to the lower large-diameter inner peripheral surface 7a1 of the bearing member 17, the lower end surface 8c of the sleeve portion 8 is brought into contact with the upper end surface 2b1 of the flange portion 2b of the shaft member 2, and the flange The upper end surface 7b1 of the housing bottom 7b is brought into contact with the lower end surface 2b2 of the portion 2b, so that both thrust bearing gaps are in a zero state. Then, the housing bottom portion 7b is fixed to the inner peripheral surface 7a1 of the housing side portion 7a so that the housing 7 and the sleeve portion 8 are immovable. Since the subsequent method of forming the thrust bearing gap is the same as that in the above embodiment, the description thereof is omitted.

図１１に示すような動圧軸受装置１にも本発明の製造方法を適用することができる。この動圧軸受装置１は、ハウジング７の開口部でシール空間が２箇所形成されている点で上記の動圧軸受装置と異なる。具体的には、ハウジング７の開口部に配されるシール部材１９が、円盤部１９ａと、円盤部１９ａの外径端から下方へ延びた円筒部１９ｂとからなる断面Ｌ字型に形成される。シール部材１９の円盤部１９ａの内周面１９ａ２は上方へ向けて拡径したテーパ面状に形成され、円筒部１９ｂの外周面１９ｂ１及び内周面１９ｂ２は円筒面状に形成される。また、ハウジング７の側部７ａの開口端部には、側部７ａよりも大径な大径部７ｃが形成され、この大径部７ｃの内周面７ｃ１は上方へ向けて拡径したテーパ状に形成される。   The manufacturing method of the present invention can also be applied to a hydrodynamic bearing device 1 as shown in FIG. The hydrodynamic bearing device 1 is different from the hydrodynamic bearing device described above in that two seal spaces are formed at the opening of the housing 7. Specifically, the seal member 19 disposed in the opening of the housing 7 is formed in an L-shaped cross section including a disc portion 19a and a cylindrical portion 19b extending downward from the outer diameter end of the disc portion 19a. . The inner peripheral surface 19a2 of the disk portion 19a of the seal member 19 is formed in a tapered surface shape whose diameter is increased upward, and the outer peripheral surface 19b1 and the inner peripheral surface 19b2 of the cylindrical portion 19b are formed in a cylindrical surface shape. A large-diameter portion 7c having a diameter larger than that of the side portion 7a is formed at the opening end portion of the side portion 7a of the housing 7, and the inner peripheral surface 7c1 of the large-diameter portion 7c is a taper whose diameter is increased upward. It is formed in a shape.

シール部材１９は、円盤部１９ａの下側端面１９ａ１がスリーブ部８の上側端面８ｂに固定されると共に、円筒部１９ｂの内周面１９ｂ２がスリーブ部８の外周面８ｄに嵌合する。この状態で、シール部材１９の円筒部１９ｂの下端は、ハウジング７の側部７ａと大径部７ｃとの間に形成された肩面７ｅと軸方向隙間２０を介して対向する。   The seal member 19 has a lower end surface 19 a 1 of the disk portion 19 a fixed to the upper end surface 8 b of the sleeve portion 8, and an inner peripheral surface 19 b 2 of the cylindrical portion 19 b is fitted to the outer peripheral surface 8 d of the sleeve portion 8. In this state, the lower end of the cylindrical portion 19 b of the seal member 19 faces the shoulder surface 7 e formed between the side portion 7 a and the large diameter portion 7 c of the housing 7 with the axial gap 20 therebetween.

軸部材２が回転すると、シール部材１９の円盤部１９ａの内周面１９ａ２と軸部材２の軸部２ａの外周面２ａ１との間に、下方へ向けて径方向寸法が漸次縮小した第１シール空間Ｓ１が形成される。同時に、シール部材１９の円筒部１９ｂの外周面１９ｂ１とハウジング７の大径部７ｃの内周面７ｃ１との間に、下方へ向けて径方向寸法が漸次縮小した第２シール空間Ｓ２が形成される。シール部材１９の円盤部１９ａの下側端面１９ａ１には径方向溝１９ａ１０が形成され、この径方向溝１９ａ１０、及びスリーブ部８の外周面８ｄに形成された軸方向溝８ｄ１により、第１スラスト軸受部の軸受隙間の外径端、第１シール空間Ｓ１、及び第２シール空間Ｓ２が連通する。   When the shaft member 2 rotates, a first seal whose radial dimension gradually decreases downward between the inner peripheral surface 19a2 of the disk portion 19a of the seal member 19 and the outer peripheral surface 2a1 of the shaft portion 2a of the shaft member 2. A space S1 is formed. At the same time, a second seal space S2 is formed between the outer peripheral surface 19b1 of the cylindrical portion 19b of the seal member 19 and the inner peripheral surface 7c1 of the large-diameter portion 7c of the housing 7 so that the radial dimension gradually decreases downward. The A radial groove 19a10 is formed in the lower end surface 19a1 of the disk portion 19a of the seal member 19, and the first thrust bearing is formed by the radial groove 19a10 and the axial groove 8d1 formed in the outer peripheral surface 8d of the sleeve portion 8. The outer diameter end of the bearing gap of the first portion, the first seal space S1, and the second seal space S2 communicate with each other.

以上の実施形態では、ラジアル動圧発生部としてヘリングボーン形状の動圧溝８ａ１、８ａ２が形成されているが、これに限らず、例えばスパイラル形状の動圧溝やステップ軸受、あるいは多円弧軸受を採用してもよい。また、上記では、スラスト動圧発生部としてスパイラル形状の動圧溝が形成されているが、これに限らず、例えばヘリングボーン形状の動圧溝やステップ軸受、あるいは波型軸受（ステップ型が波型になったもの）等を採用することもできる。   In the above embodiment, the herringbone-shaped dynamic pressure grooves 8a1 and 8a2 are formed as the radial dynamic pressure generating portion. However, the present invention is not limited to this. For example, a spiral-shaped dynamic pressure groove, a step bearing, or a multi-arc bearing is used. It may be adopted. In the above description, the spiral dynamic pressure groove is formed as the thrust dynamic pressure generating portion. However, the present invention is not limited to this. For example, a herringbone-shaped dynamic pressure groove, a step bearing, or a wave bearing (the step type is a wave). It is also possible to adopt a type).

また、上記では、動圧発生部がスリーブ部８の内周面８ａ、下側端面８ｃ、およびハウジング底部７ｂの上側端面７ｂ１に形成されているが、それぞれと軸受隙間を介して対向する面、すなわち軸部２ａの外周面２ａ１、フランジ部２ｂの上側端面２ｂ１、および下側端面２ｂ２に動圧発生部を設けてもよい。   In the above, the dynamic pressure generating portion is formed on the inner peripheral surface 8a, the lower end surface 8c of the sleeve portion 8, and the upper end surface 7b1 of the housing bottom portion 7b. That is, a dynamic pressure generating portion may be provided on the outer peripheral surface 2a1 of the shaft portion 2a, the upper end surface 2b1 and the lower end surface 2b2 of the flange portion 2b.

また、以上の実施形態では、ラジアル軸受部Ｒ１、Ｒ２が軸方向で離隔して設けられているが、これらを軸方向で連続的に設けてもよい。あるいは、これらの何れか一方のみを設けてもよい。   Further, in the above embodiment, the radial bearing portions R1 and R2 are provided separately in the axial direction, but these may be provided continuously in the axial direction. Alternatively, only one of these may be provided.

また、以上の実施形態では、動圧軸受装置１の内部に充満し、ラジアル軸受隙間や、スラスト軸受隙間に動圧作用を生じる流体として、潤滑油を例示したが、それ以外にも各軸受隙間に動圧作用を発生可能な流体、例えば空気等の気体や、磁性流体、あるいは潤滑グリース等を使用することもできる。   Further, in the above embodiment, the lubricating oil is exemplified as the fluid that fills the inside of the hydrodynamic bearing device 1 and causes the hydrodynamic action in the radial bearing gap or the thrust bearing gap. In addition, a fluid capable of generating a dynamic pressure action, for example, a gas such as air, a magnetic fluid, or lubricating grease can be used.

また、本発明の方法で製造された動圧軸受装置は、上記のようにＨＤＤ等のディスク駆動装置に用いられるスピンドルモータに限らず、光ディスクの光磁気ディスク駆動用のスピンドルモータ等、高速回転下で使用される情報機器用の小型モータ、レーザビームプリンタのポリゴンスキャナモータ等における回転軸支持用、あるいは電気機器の冷却ファン用のファンモータとしても好適に使用することができる。   Further, the hydrodynamic bearing device manufactured by the method of the present invention is not limited to the spindle motor used for the disk drive device such as the HDD as described above, but is a spindle motor for driving the magneto-optical disk of the optical disk, etc. It can be suitably used as a fan motor for supporting a rotating shaft in a small motor for information equipment, a polygon scanner motor of a laser beam printer, or a cooling fan for electric equipment.

動圧軸受装置を組み込んだスピンドルモータの断面図である。It is sectional drawing of the spindle motor incorporating the dynamic pressure bearing apparatus. 動圧軸受装置の断面図である。It is sectional drawing of a hydrodynamic bearing apparatus. （ａ）は、スリーブ部の断面図である。（ｂ）は、スリーブ部の下面図である。(A) is sectional drawing of a sleeve part. (B) is a bottom view of a sleeve part. 図２のハウジングのＡ−Ａ断面を矢印方向に見た断面図である。It is sectional drawing which looked at the AA cross section of the housing of FIG. 2 in the arrow direction. ローリング加工を示す斜視図である。It is a perspective view which shows a rolling process. （ａ）、（ｂ）は、スラスト軸受隙間の幅設定の方法を示す断面図である。(A), (b) is sectional drawing which shows the method of the width | variety setting of a thrust bearing clearance gap. ハウジング側部の凹部周辺を示す拡大断面図である。It is an expanded sectional view which shows the recessed part periphery of a housing side part. 他の例のハウジング側部の凹部周辺を示す拡大断面図である。It is an expanded sectional view which shows the recessed part periphery of the housing side part of another example. （ａ）、（ｂ）は、他の例に係るスラスト軸受隙間の幅設定の方法を示す断面図である。(A), (b) is sectional drawing which shows the method of the width | variety setting of the thrust bearing clearance concerning other examples. 他の例の動圧軸受装置の断面図である。It is sectional drawing of the hydrodynamic bearing apparatus of another example. 他の例の動圧軸受装置の断面図である。It is sectional drawing of the hydrodynamic bearing apparatus of another example. 比較例としてのスラスト軸受隙間の幅設定の方法を示す断面図である。It is sectional drawing which shows the method of the width setting of the thrust bearing clearance as a comparative example. 比較例としてのスラスト軸受隙間の幅設定の方法を示す断面図である。It is sectional drawing which shows the method of the width setting of the thrust bearing clearance as a comparative example. 比較例としてのスラスト軸受隙間の幅設定の方法を示す断面図である。It is sectional drawing which shows the method of the width setting of the thrust bearing clearance as a comparative example.

符号の説明Explanation of symbols

１ 動圧軸受装置
２ 軸部材
２ａ 軸部
２ｂ フランジ部
７ ハウジング
７ａ 側部
７ａ２０ 凹部
７ｂ 底部
８ スリーブ部
９ シール部
１０ サブアッシ品
Ｒ１、Ｒ２ ラジアル軸受部
Ｔ１、Ｔ２ スラスト軸受部
Ｓ シール空間 DESCRIPTION OF SYMBOLS 1 Dynamic pressure bearing apparatus 2 Shaft member 2a Shaft part 2b Flange part 7 Housing 7a Side part 7a20 Recessed part 7b Bottom part 8 Sleeve part 9 Seal part 10 Sub-assembly R1, R2 Radial bearing part T1, T2 Thrust bearing part S Seal space

Claims (6)

側部および底部を有するハウジングと、ハウジングの内周に設けられたスリーブ部と、軸部及びフランジ部を有する軸部材と、スリーブ部の内周面と軸部の外周面との間に形成されたラジアル軸受隙間と、フランジ部の両端面に面する二つのスラスト軸受隙間とを備え、各軸受隙間に生じる潤滑流体の動圧作用で軸部材をラジアル方向及びスラスト方向に支持する動圧軸受装置を製造するための方法であって、
両スラスト軸受隙間を０にした状態で、ハウジング側部を軸方向に塑性変形させて両スラスト軸受隙間を形成することを特徴とする動圧軸受装置の製造方法。 Formed between a housing having side portions and a bottom portion, a sleeve portion provided on an inner periphery of the housing, a shaft member having a shaft portion and a flange portion, and an inner peripheral surface of the sleeve portion and an outer peripheral surface of the shaft portion. The hydrodynamic bearing device includes a radial bearing gap and two thrust bearing gaps facing both end faces of the flange portion, and supports the shaft member in the radial direction and the thrust direction by the dynamic pressure action of the lubricating fluid generated in each bearing gap. A method for manufacturing
A method of manufacturing a hydrodynamic bearing device, wherein both thrust bearing gaps are formed by plastically deforming the side portions of the housing in the axial direction with both thrust bearing gaps being zero. フランジ部の端面と対向したスリーブ部の端面よりもスリーブ部側でハウジングの側部外周面を加圧してハウジング側部を塑性変形させる請求項１記載の動圧軸受装置の製造方法。   2. The method of manufacturing a hydrodynamic bearing device according to claim 1, wherein the outer peripheral surface of the side of the housing is pressed closer to the sleeve portion than the end surface of the sleeve portion facing the end surface of the flange portion to plastically deform the housing side portion. 加圧領域をスリーブ部の前記端面の外周チャンファと対向させた請求項２記載の動圧軸受装置の製造方法。   The method of manufacturing a hydrodynamic bearing device according to claim 2, wherein the pressurizing region is opposed to the outer peripheral chamfer on the end surface of the sleeve portion. ハウジング底部の軸方向変位を検知しながらハウジングを軸方向に塑性変形させる請求項１〜３の何れかに記載の動圧軸受装置の製造方法。   The method of manufacturing a hydrodynamic bearing device according to claim 1, wherein the housing is plastically deformed in the axial direction while detecting an axial displacement of the bottom of the housing. 側部および底部を有するハウジングと、ハウジングの内周に設けられたスリーブ部と、軸部及びフランジ部を有する軸部材と、スリーブ部の内周面と軸部の外周面との間に形成されたラジアル軸受隙間と、フランジ部の両端面に面する二つのスラスト軸受隙間とを備え、各軸受隙間に生じる潤滑流体の動圧作用で軸部材をラジアル方向及びスラスト方向に支持する動圧軸受装置において、
両スラスト軸受隙間を、ハウジングの軸方向の塑性変形で形成したことを特徴とする動圧軸受装置。 Formed between a housing having side portions and a bottom portion, a sleeve portion provided on an inner periphery of the housing, a shaft member having a shaft portion and a flange portion, and an inner peripheral surface of the sleeve portion and an outer peripheral surface of the shaft portion. The hydrodynamic bearing device includes a radial bearing gap and two thrust bearing gaps facing both end faces of the flange portion, and supports the shaft member in the radial direction and the thrust direction by the dynamic pressure action of the lubricating fluid generated in each bearing gap. In
A hydrodynamic bearing device in which both thrust bearing gaps are formed by plastic deformation in the axial direction of the housing. ハウジングの側部外周面を加圧してハウジングを塑性変形させ、塑性変形で形成された凹部を接着剤溜りとした請求項５記載の動圧軸受装置。   6. The hydrodynamic bearing device according to claim 5, wherein the housing is plastically deformed by pressurizing a side outer peripheral surface of the housing, and a concave portion formed by the plastic deformation is used as an adhesive reservoir.
JP2007177553A 2007-07-05 2007-07-05 Dynamic pressure bearing device and its manufacturing method Withdrawn JP2009014121A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2007177553A JP2009014121A (en) 2007-07-05 2007-07-05 Dynamic pressure bearing device and its manufacturing method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2007177553A JP2009014121A (en) 2007-07-05 2007-07-05 Dynamic pressure bearing device and its manufacturing method

Publications (1)

Publication Number Publication Date
JP2009014121A true JP2009014121A (en) 2009-01-22

Family

ID=40355258

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2007177553A Withdrawn JP2009014121A (en) 2007-07-05 2007-07-05 Dynamic pressure bearing device and its manufacturing method

Country Status (1)

Country Link
JP (1) JP2009014121A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015172384A (en) * 2014-03-11 2015-10-01 Ntn株式会社 Sintered bearing, fluid dynamic-pressure bearing device and motor having the bearing, and sintered bearing manufacturing method
CN111609033A (en) * 2020-06-08 2020-09-01 哈尔滨电气动力装备有限公司 Water-lubricated asymmetric self-adjusting bidirectional working thrust bearing for shielded motor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015172384A (en) * 2014-03-11 2015-10-01 Ntn株式会社 Sintered bearing, fluid dynamic-pressure bearing device and motor having the bearing, and sintered bearing manufacturing method
CN111609033A (en) * 2020-06-08 2020-09-01 哈尔滨电气动力装备有限公司 Water-lubricated asymmetric self-adjusting bidirectional working thrust bearing for shielded motor
CN111609033B (en) * 2020-06-08 2021-08-13 哈尔滨电气动力装备有限公司 Water-lubricated asymmetric self-adjusting bidirectional working thrust bearing for shielded motor

Similar Documents

Publication Publication Date Title
JP5207657B2 (en) Method for manufacturing hydrodynamic bearing device
JP6502068B2 (en) Method of manufacturing fluid dynamic bearing device
JP2009014121A (en) Dynamic pressure bearing device and its manufacturing method
JP2009168147A (en) Dynamic pressure bearing device and its manufacturing method
JP2008190711A (en) Manufacturing process for hydrodynamic bearing unit
JP4172944B2 (en) Hydrodynamic bearing device and manufacturing method thereof
JP2009228873A (en) Fluid bearing device
JP2008298235A (en) Fluid bearing device and its assembling method
WO2005088143A1 (en) Hydrodynamic bearing device
JP5143435B2 (en) Manufacturing method of shaft member for hydrodynamic bearing device, and shaft member manufactured by the method
JP5064083B2 (en) Method for manufacturing hydrodynamic bearing device
JP5901979B2 (en) Method for manufacturing fluid dynamic bearing device
JP4588561B2 (en) Hydrodynamic bearing device
JP5606831B2 (en) Bearing member and manufacturing method thereof
JP6981900B2 (en) Fluid dynamic bearing device and motor equipped with it
JP4554324B2 (en) Hydrodynamic bearing device
JP2005265180A (en) Dynamic pressure bearing device
JP2008075687A (en) Fluid bearing device
JP4233771B2 (en) Hydrodynamic bearing unit
JP4498932B2 (en) Hydrodynamic bearing device
JP5172213B2 (en) Hydrodynamic bearing device and method for manufacturing shaft member thereof
JP2007170574A (en) Fluid bearing device
JP4675880B2 (en) Method for manufacturing fluid dynamic bearing device
JP2013053692A (en) Fluid dynamic pressure bearing device and method of manufacturing the same
JP2008275132A (en) Fluid bearing device

Legal Events

Date Code Title Description
RD04 Notification of resignation of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7424

Effective date: 20091104

A300 Withdrawal of application because of no request for examination

Free format text: JAPANESE INTERMEDIATE CODE: A300

Effective date: 20100907