JP4515151B2 - Hydrodynamic bearing device - Google Patents
Hydrodynamic bearing device Download PDFInfo
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- JP4515151B2 JP4515151B2 JP2004149632A JP2004149632A JP4515151B2 JP 4515151 B2 JP4515151 B2 JP 4515151B2 JP 2004149632 A JP2004149632 A JP 2004149632A JP 2004149632 A JP2004149632 A JP 2004149632A JP 4515151 B2 JP4515151 B2 JP 4515151B2
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- rotating member
- thrust bearing
- dynamic pressure
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- 239000011347 resin Substances 0.000 claims description 33
- 229920005989 resin Polymers 0.000 claims description 33
- 239000002184 metal Substances 0.000 claims description 32
- 229910052751 metal Inorganic materials 0.000 claims description 32
- 239000000463 material Substances 0.000 claims description 15
- 239000007769 metal material Substances 0.000 claims description 15
- 230000002093 peripheral effect Effects 0.000 claims description 15
- 239000010687 lubricating oil Substances 0.000 claims description 12
- 239000000853 adhesive Substances 0.000 claims description 10
- 230000001070 adhesive effect Effects 0.000 claims description 10
- 238000007789 sealing Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 description 7
- BGPVFRJUHWVFKM-UHFFFAOYSA-N N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] Chemical compound N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] BGPVFRJUHWVFKM-UHFFFAOYSA-N 0.000 description 4
- 239000012530 fluid Substances 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000004381 surface treatment Methods 0.000 description 4
- 238000003466 welding Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 229920000106 Liquid crystal polymer Polymers 0.000 description 2
- 239000004977 Liquid-crystal polymers (LCPs) Substances 0.000 description 2
- 238000001746 injection moulding Methods 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229910001369 Brass Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Landscapes
- Sliding-Contact Bearings (AREA)
- Motor Or Generator Frames (AREA)
Description
本発明は、軸受隙間に生じる潤滑油の動圧作用によって回転部材を回転自在に非接触支持する動圧軸受装置（流体動圧軸受装置）に関するものである。この軸受装置は、情報機器、例えばＨＤＤ等の磁気ディスク装置、ＣＤ−ＲＯＭ、ＣＤ−Ｒ／ＲＷ、ＤＶＤ−ＲＯＭ／ＲＡＭ等の光ディスク装置、ＭＤ、ＭＯ等の光磁気ディスク装置等のスピンドルモータ用として好適である。 The present invention relates to a hydrodynamic bearing device (fluid hydrodynamic bearing device) that rotatably supports a rotating member in a non-contact manner by the hydrodynamic action of lubricating oil generated in a bearing gap. This bearing device is used for spindle motors of information equipment, for example, magnetic disk devices such as HDD, optical disk devices such as CD-ROM, CD-R / RW, DVD-ROM / RAM, and magneto-optical disk devices such as MD and MO. It is suitable as.
上記各種モータには、高回転精度の他、高速化、低コスト化、低騒音化等が求められている。これらの要求性能を決定づける構成要素の１つに当該モータのスピンドルを支持する軸受があり、近年では、上記要求性能に優れた特性を有する動圧軸受の使用が検討され、あるいは実際に使用されている。 In addition to high rotational accuracy, the various motors are required to have high speed, low cost, low noise, and the like. One of the components that determine the required performance is a bearing that supports the spindle of the motor. In recent years, the use of a hydrodynamic bearing having characteristics excellent in the required performance has been studied or actually used. Yes.
例えば、ＨＤＤ等のディスク駆動装置のスピンドルモータには、軸部を備えた回転部材をラジアル方向に非接触支持するラジアル軸受部と、回転部材をスラスト方向に非接触支持するスラスト軸受部とを備えた動圧軸受装置が用いられる。この種の動圧軸受装置において、ラジアル軸受部を構成する軸受スリーブの内周面または軸部の外周面に動圧発生手段としての動圧溝が設けられる。また、スラスト軸受部を構成する軸部のフランジ部の両端面、あるいは、これに対向する面（例えば軸受スリーブの端面や、ハウジング底部の端面あるいはハウジングに固定されるスラストプレートの端面等）に動圧溝が設けられる（例えば、特許文献１参照）。
上記構成の動圧軸受装置は、ハウジング、軸受スリーブ、回転部材といった部品で構成され、情報機器の益々の高性能化に伴って必要とされる高い回転性能を確保すべく、各部品の加工精度や組立て精度を高める努力がなされている。その一方で、情報機器の低価格化の傾向に伴い、この種の動圧軸受装置に対するコスト低減の要求も益々厳しくなっている。 The hydrodynamic bearing device configured as described above is composed of components such as a housing, a bearing sleeve, and a rotating member, and processing accuracy of each component is ensured to ensure high rotational performance required as information devices increase in performance. Efforts have been made to improve assembly accuracy. On the other hand, along with the trend of price reduction of information equipment, the demand for cost reduction for this type of hydrodynamic bearing device has become increasingly severe.
ところで最近では、ハウジングの軽量化および製造コストの低減を目的として、ハウジングを樹脂材料で成形することが検討されている。その場合には、樹脂製のハウジングと、このハウジングを保持するモータブラケット等の金属製部材とを確実に固定する必要が生じる。特に、携帯型の情報機器に用いられる動圧軸受装置には、高い耐衝撃特性が要求されるので、さらなる固定力の向上が望まれる。 Recently, for the purpose of reducing the weight of the housing and reducing the manufacturing cost, it has been studied to mold the housing with a resin material. In that case, it is necessary to securely fix the resin housing and a metal member such as a motor bracket holding the housing. In particular, a hydrodynamic bearing device used in a portable information device is required to have high impact resistance, and thus further improvement in fixing force is desired.
高い固定力を得るための方法として、例えば接着を挙げることができる。その場合には金属材料と樹脂材料との間の接着力を高める手段として、例えばアルカリエッチングやプラズマエッチング、あるいはＵＶ処理等の表面処理を樹脂成形面に施す方法が知られている。ところが、この方法では、ハウジングを樹脂材料で型成形した後、さらに接着固定面に表面処理を別途行う必要が生じるため加工工程が増加し、製造コストの増加につながる。 As a method for obtaining a high fixing force, for example, adhesion can be mentioned. In that case, as a means for increasing the adhesive force between the metal material and the resin material, for example, a method of performing surface treatment such as alkali etching, plasma etching, or UV treatment on the resin molding surface is known. However, in this method, after the housing is molded with a resin material, it is necessary to separately perform a surface treatment on the adhesive fixing surface, which increases processing steps and leads to an increase in manufacturing cost.
そこで、本発明は、この種の動圧軸受装置におけるハウジングの製造コストを低減するとともに、ハウジングと他の金属製部材との間の固定強度を高めることを目的とする。 Accordingly, an object of the present invention is to reduce the manufacturing cost of the housing in this type of fluid dynamic bearing device and to increase the fixing strength between the housing and another metal member.
前記課題を解決するため、本発明に係る動圧軸受装置は、ハウジングと、ハウジングの内部に固定された軸受スリーブと、軸受スリーブ及びハウジングに対して相対回転する回転部材と、回転部材と軸受スリーブとの間のラジアル軸受隙間に生じる潤滑油の動圧作用で回転部材をラジアル方向に非接触支持するラジアル軸受部と、回転部材とハウジングとの間のスラスト軸受隙間に生じる潤滑油の動圧作用で回転部材をスラスト方向に非接触支持するスラスト軸受部とを備えたものにおいて、ハウジングは、円筒状の側部と、側部の一端側に位置する開口部と、側部の他端側に位置する底部とを備えるもので、スラスト軸受部を構成し、かつ動圧溝が形成されたスラスト軸受面と、他の金属製部材が接着で固定される接着固定面、および回転部材との間に潤滑油のシール空間を形成するテーパ状の外壁を有し、スラスト軸受面は、側部の開口部側の端面に形成され、接着固定面は、側部の底部側の外周面に形成され、テーパ状の外壁は、側部の開口部側の外周面に形成され、側部の、スラスト軸受面を含む部分を樹脂材料で形成し、接着固定面を含む部分を金属材料で形成したことを特徴とする。ここで「他の金属製部材」は、動圧軸受装置の構成部品に限るものではなく、ハウジングに固定するものを全て含む。例えば、軸受スリーブを金属材料で形成し、ハウジングの内周面に固定する場合には、該軸受スリーブがここでいう他の金属製部材に該当し、また、動圧軸受装置のハウジングの外周面が固定される金属製のモータブラケットがここでいう他の金属製部材に該当する。 In order to solve the above problems, a hydrodynamic bearing device according to the present invention includes a housing, a bearing sleeve fixed inside the housing, a bearing sleeve and a rotating member that rotates relative to the housing, and the rotating member and the bearing sleeve. The dynamic pressure action of the lubricating oil generated in the radial bearing gap between the rotating member and the housing, and the radial bearing portion that supports the rotating member in the radial direction by the dynamic pressure action of the lubricating oil generated in the radial bearing gap between the rotating member and the housing The housing is provided with a thrust bearing portion that supports the rotating member in the thrust direction in a non-contact manner , and the housing has a cylindrical side portion, an opening located at one end side of the side portion, and the other end side of the side portion. as it has a bottom part located, adhesion fixing face and the thrust bearing surface constitutes the thrust bearing portion, and dynamic pressure grooves are formed, the other metallic member is fixed with an adhesive, and rotation Has a tapered outer wall which forms a seal space of the lubricating oil between the wood, the thrust bearing surface is formed on the end face of the opening side of the side, bonded surface, the outer periphery of the bottom side of the side The tapered outer wall is formed on the outer peripheral surface of the opening on the side, the portion including the thrust bearing surface of the side is formed of a resin material, and the portion including the adhesive fixing surface is a metal material It is formed by. Here, the “other metal members” are not limited to the components of the hydrodynamic bearing device, but include all those fixed to the housing. For example, when the bearing sleeve is formed of a metal material and is fixed to the inner peripheral surface of the housing, the bearing sleeve corresponds to the other metal member here, and the outer peripheral surface of the housing of the hydrodynamic bearing device The metal motor bracket to which is fixed corresponds to the other metal member here.
一般に、金属材料同士を固定すれば、両者間で高い固定力を得やすい。本発明では、このことを利用して、他の金属製部材が固定される固定面を含む部分を金属材料で形成したので、ハウジングと他の金属製部材とを確実に固定することができる。特に、他の金属製部材との固定を接着により行う場合には、固定面におけるハウジングと他の金属製部材との間の接着強度を高めることができる。また、ハウジングの固定面を含む部分を樹脂材料で型成形した後、成形した固定面に別途表面処理を施す工程を省略でき、製造コストの低減化が図られる。 Generally, if metal materials are fixed, it is easy to obtain a high fixing force between them. In the present invention, by utilizing this, the portion including the fixing surface to which the other metal member is fixed is formed of the metal material, so that the housing and the other metal member can be reliably fixed. In particular, when the other metal member is fixed by bonding, the bonding strength between the housing and the other metal member on the fixing surface can be increased. In addition, after the portion including the fixed surface of the housing is molded with a resin material, a step of separately subjecting the molded fixed surface to a surface treatment can be omitted, and the manufacturing cost can be reduced.
また、本発明では、ハウジングのスラスト軸受面を含む部分を樹脂材料で形成したので、動圧溝を、スラスト軸受面を含む部分と同時に樹脂材料で型成形することができ、スラスト軸受面を含む部分を金属材料で形成した場合と比べて、動圧溝を別途加工する手間を省くことができる。これにより、動圧溝の加工工程が簡略化され、より一層の低コスト化が図られる。 Further, in the present invention, since the portion including the thrust bearing surface of the housing is formed of the resin material, the dynamic pressure groove can be molded with the resin material simultaneously with the portion including the thrust bearing surface, and includes the thrust bearing surface. Compared to the case where the portion is made of a metal material, it is possible to save the trouble of separately processing the dynamic pressure groove. Thereby, the machining process of the dynamic pressure groove is simplified, and the cost can be further reduced.
本発明の動圧軸受装置は、ハウジングが、上記のような金属部分と樹脂部分とのハイブリッド構造を有するので、ハウジングの軽量化および製造コストの低減を図りつつ、他の金属製部材との接着力を充分に確保することが可能となる。 In the hydrodynamic bearing device of the present invention, since the housing has the hybrid structure of the metal part and the resin part as described above, the housing can be reduced in weight and the manufacturing cost can be reduced, and can be bonded to another metal member. It is possible to secure sufficient force.
上記構成のハウジングの側部は、金属材料で形成された接着固定面を含む部分をインサート部品として樹脂材料で射出成形することにより、容易に製造することができる。 The side part of the housing having the above-described structure can be easily manufactured by injection-molding a resin material as a part including an adhesive fixing surface formed of a metal material.
ハウジングは、例えば、円筒状の側部と、側部の一端側に位置する開口部と、側部の他端側に位置する底部とを備え、開口部の側にスラスト軸受面を有する構造とすることができる。 The housing includes, for example, a cylindrical side portion, an opening portion located on one end side of the side portion, and a bottom portion located on the other end side of the side portion, and a structure having a thrust bearing surface on the opening portion side. can do.
あるいは、ハウジングは、円筒状の側部と、側部の一端側に位置する開口部と、側部の他端側に位置する底部とを備え、底部の側にスラスト軸受面を有する構造とすることもできる。 Alternatively, the housing includes a cylindrical side portion, an opening located on one end side of the side portion, and a bottom portion located on the other end side of the side portion, and has a thrust bearing surface on the bottom side. You can also.
以上のように、本発明によれば、この種の動圧軸受装置におけるハウジングの軽量化と製造コストの低減を図りつつ、ハウジングと他の金属製部材との間の固定強度を高めて、例えば携帯型情報機器の使用にも耐え得る高い耐衝撃特性を付与することができる。 As described above, according to the present invention, while reducing the weight of the housing and reducing the manufacturing cost in this type of hydrodynamic bearing device, the fixing strength between the housing and another metal member can be increased, for example, High impact resistance that can withstand the use of portable information equipment can be imparted.
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、本発明の一実施形態に係る動圧軸受装置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。この情報機器用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、軸部２を備えた回転部材３を回転自在に非接触支持する動圧軸受装置１と、例えば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、金属製のモータブラケット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の外周に取り付けられ、ロータマグネット５は回転部材３の外周に取り付けられている。動圧軸受装置１のハウジング７は、モータブラケット６の内周に例えば接着等の手段により固定される。回転部材３には、磁気ディスク等のディスク状情報記録媒体が一又は複数枚保持される。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、それによって回転部材３および軸部２が一体となって回転する。 FIG. 1 conceptually shows a configuration example of a spindle motor for information equipment incorporating a fluid dynamic bearing device 1 according to an embodiment of the present invention. This spindle motor for information equipment is used in a disk drive device such as an HDD, and has a hydrodynamic bearing device 1 that rotatably supports a rotating member 3 having a shaft portion 2 in a non-contact manner, for example, a radial gap. The stator coil 4 and the rotor magnet 5 that are opposed to each other, and a metal 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 outer periphery of the rotating member 3. The housing 7 of the hydrodynamic bearing device 1 is fixed to the inner periphery of the motor bracket 6 by means such as adhesion. The rotating member 3 holds one or more disk-shaped information recording media such as a magnetic disk. When the stator coil 4 is energized, the rotor magnet 5 is rotated by electromagnetic force generated between the stator coil 4 and the rotor magnet 5, thereby rotating the rotating member 3 and the shaft portion 2 together.
動圧軸受装置１は、例えば図２に示すように、一端側に開口部７ｂ、他端側に底部７ｃを有するハウジング７と、ハウジング７の内部に固定された軸受スリーブ８と、ハウジング７及び軸受スリーブ８に対して相対回転する回転部材３とを備えている。なお、説明の便宜上、ハウジング７の開口部７ｂ側を上方向、ハウジング７の底部７ｃ側を下方向として以下説明する。 For example, as shown in FIG. 2, the hydrodynamic bearing device 1 includes a housing 7 having an opening 7b on one end side and a bottom 7c on the other end side, a bearing sleeve 8 fixed inside the housing 7, a housing 7 and And a rotating member 3 that rotates relative to the bearing sleeve 8. For convenience of explanation, the following description will be made with the opening 7b side of the housing 7 as the upward direction and the bottom 7c side of the housing 7 as the downward direction.
回転部材３は、例えばハウジング７の開口部７ｂの側に被冠状に装着されるハブ部９と、軸受スリーブ８の内周に挿入される軸部２とで構成される。 The rotating member 3 includes a hub portion 9 that is mounted in a crowned manner on the opening 7 b side of the housing 7 and a shaft portion 2 that is inserted into the inner periphery of the bearing sleeve 8, for example.
ハブ部９は、ハウジング７の開口部７ｂの側を覆う円盤状の主部９ａと、主部９ａの外周部から軸方向下方に延びた筒状部９ｂと、筒状部９ｂの外周に設けられたディスク搭載面９ｃおよび鍔部９ｄとを備えている。図示されていないディスク状情報記録媒体は、主部９ａの外周に外嵌され、ディスク搭載面９ｃに載置される。そして、図示しない適当な保持手段によってディスク状情報記録媒体がハブ部９に保持される。 The hub portion 9 is provided on a disc-shaped main portion 9a covering the opening 7b side of the housing 7, a cylindrical portion 9b extending downward in the axial direction from the outer peripheral portion of the main portion 9a, and an outer periphery of the cylindrical portion 9b. The disc mounting surface 9c and the flange portion 9d are provided. A disc-shaped information recording medium (not shown) is fitted around the outer periphery of the main portion 9a and placed on the disc mounting surface 9c. The disc-shaped information recording medium is held on the hub portion 9 by an appropriate holding means (not shown).
軸部２は、この実施形態ではハブ部９と一体に形成され、その下端にフランジ部１０を別体に備えている。フランジ部１０は、例えばねじ結合等の手段により軸部２に固定される。 The shaft portion 2 is formed integrally with the hub portion 9 in this embodiment, and includes a flange portion 10 at a lower end thereof. The flange portion 10 is fixed to the shaft portion 2 by means such as screw connection.
軸受スリーブ８は、例えば、焼結金属からなる多孔質体、特に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。 The bearing sleeve 8 is formed in a cylindrical shape, for example, with a porous body made of sintered metal, in particular, a sintered metal porous body mainly composed of copper.
軸受スリーブ８の内周面８ａには、図２に示すように、第１ラジアル軸受部Ｒ１と第２ラジアル軸受部Ｒ２のラジアル軸受面となる上下２つの領域が軸方向に離隔して設けられている。上記２つの領域には、例えば、図３（ａ）に示すようなへリングボーン形状の動圧溝８ａ１、８ａ２がそれぞれ形成されている。上側の動圧溝８ａ１は、軸方向中心ｍ（上下の傾斜溝間領域の軸方向中央）に対して軸方向非対称に形成されており、軸方向中心ｍより上側領域の軸方向寸法Ｘ１が下側領域の軸方向寸法Ｘ２よりも大きくなっている。また、軸受スリーブ８の外周面８ｂには、１本又は複数本の軸方向溝８ｂ１が軸方向全長に亘って形成されている。この実施形態では、３本の軸方向溝８ｂ１を円周方向等間隔に形成している。 On the inner peripheral surface 8a of the bearing sleeve 8, as shown in FIG. 2, two upper and lower regions serving as radial bearing surfaces of the first radial bearing portion R1 and the second radial bearing portion R2 are provided apart in the axial direction. ing. For example, herringbone-shaped dynamic pressure grooves 8a1 and 8a2 as shown in FIG. 3A are formed in the two regions. The upper dynamic pressure groove 8a1 is formed axially asymmetric with respect to the axial center m (the axial center of the upper and lower inclined groove regions), and the axial dimension X1 of the upper region is lower than the axial center m. It is larger than the axial dimension X2 of the side region. Further, one or a plurality of axial grooves 8b1 are formed on the outer peripheral surface 8b of the bearing sleeve 8 over the entire axial length. In this embodiment, three axial grooves 8b1 are formed at equal intervals in the circumferential direction.
軸受スリーブ８の下側端面８ｃの、スラスト軸受部Ｔ２のスラスト軸受面となる領域には、例えば、図３（ｂ）に示すような動圧溝８ｃ１が形成される。 For example, a dynamic pressure groove 8c1 as shown in FIG. 3B is formed in a region of the lower end surface 8c of the bearing sleeve 8 that becomes the thrust bearing surface of the thrust bearing portion T2.
ハウジング７は、側部７ａと、側部７ａの一端側に位置する開口部７ｂと、側部７ａの他端側に位置する底部７ｃとを備えている。側部７ａは、円筒状の金属部７ａ１と、金属部７ａ１の外周上部に設けられた樹脂部７ａ２とで構成される。金属部７ａ１の外周下部は、図１に示すモータブラケット６の内周面６ａに例えば接着等の手段により固定される固定面７ｄ１となる。また、金属部７ａ１の内周面は、この実施形態では、金属製の軸受スリーブ８が例えば接着等の手段により固定される固定面７ｄ２となる。樹脂部７ａ２の上端は、金属部７ａ１の上端と伴にハウジング７の開口部７ｂを構成している。樹脂部７ａ２の上側端面７ｂ１の、スラスト軸受部Ｔ１のスラスト軸受面となる領域には、例えば図４に示すような動圧溝７ｂ１１が形成される。 The housing 7 includes a side part 7a, an opening part 7b located on one end side of the side part 7a, and a bottom part 7c located on the other end side of the side part 7a. The side portion 7a includes a cylindrical metal portion 7a1 and a resin portion 7a2 provided on the outer periphery of the metal portion 7a1. An outer peripheral lower portion of the metal portion 7a1 serves as a fixed surface 7d1 fixed to the inner peripheral surface 6a of the motor bracket 6 shown in FIG. Further, in this embodiment, the inner peripheral surface of the metal portion 7a1 serves as a fixed surface 7d2 to which the metal bearing sleeve 8 is fixed by means such as adhesion. The upper end of the resin portion 7a2 constitutes an opening 7b of the housing 7 together with the upper end of the metal portion 7a1. For example, a dynamic pressure groove 7b11 as shown in FIG. 4 is formed in a region of the upper end surface 7b1 of the resin portion 7a2 that becomes the thrust bearing surface of the thrust bearing portion T1.
金属部７ａ１は、例えば真ちゅう等の軟質金属材料、またはその他の金属材料で形成され、樹脂部７ａ２は、例えばＬＣＰ（液晶ポリマー）やＰＰＳ等の樹脂材料で形成される。これら金属部７ａ１と樹脂部７ａ２は、この実施形態では、金属部７ａ１をインサート部品として樹脂材料の射出成形により一体に形成される。その際、樹脂部７ａ２の動圧溝７ｂ１１は、樹脂部７ａ２を成形する金型の表面に動圧溝７ｂ１１の成形型を形成しておき、樹脂部７ａ２の成形時に前記成形型の形状を樹脂部７ａ２の上側端面７ｂ１に転写することによって、樹脂部７ａ２の成形と同時に成形される。 The metal part 7a1 is formed of a soft metal material such as brass, for example, or other metal material, and the resin part 7a2 is formed of a resin material such as LCP (liquid crystal polymer) or PPS, for example. In this embodiment, the metal part 7a1 and the resin part 7a2 are integrally formed by injection molding of a resin material using the metal part 7a1 as an insert part. At that time, the dynamic pressure groove 7b11 of the resin portion 7a2 is formed with a molding die of the dynamic pressure groove 7b11 on the surface of the mold for molding the resin portion 7a2, and the shape of the molding die is changed to the resin when the resin portion 7a2 is molded. By being transferred to the upper end surface 7b1 of the portion 7a2, the resin portion 7a2 is molded at the same time.
側部７ａの下部には、側部７ａと別体に形成された底部７ｃが後付けで取り付けられる。底部７ｃは、金属材料または樹脂材料で形成される。前者の場合、底部７ｃは接着等の手段で側部７ａに固定され、後者の場合、底部７ｃは超音波溶着等の手段で側部７ａに固定される。 A bottom portion 7c formed separately from the side portion 7a is attached to the lower portion of the side portion 7a as a retrofit. The bottom 7c is made of a metal material or a resin material. In the former case, the bottom portion 7c is fixed to the side portion 7a by means such as adhesion, and in the latter case, the bottom portion 7c is fixed to the side portion 7a by means such as ultrasonic welding.
また、樹脂部７ａ２の外周には、上方に向かって漸次拡径するテーパ状の外壁７ｅが形成されている。このテーパ状の外壁７ｅは、筒状部９ｂの内周面９ｂ１との間に、ハウジング７の底部７ｃ側から上方に向けて半径方向寸法が漸次縮小した環状のシール空間Ｓを形成する。このシール空間Ｓは、軸部２およびハブ部９の回転時、スラスト軸受部Ｔ１のスラスト軸受隙間の外径側と連通している。 In addition, a tapered outer wall 7e that gradually increases in diameter upward is formed on the outer periphery of the resin portion 7a2. The tapered outer wall 7e forms an annular seal space S whose radial dimension is gradually reduced from the bottom 7c side of the housing 7 to the upper surface 9b1 of the cylindrical portion 9b. The seal space S communicates with the outer diameter side of the thrust bearing gap of the thrust bearing portion T1 when the shaft portion 2 and the hub portion 9 are rotated.
動圧軸受装置１の内部には、軸受スリーブ８の内部気孔（多孔質体組織の気孔）を含め、潤滑油が充填される。潤滑油の油面は常にシール空間Ｓ内に維持される。 The hydrodynamic bearing device 1 is filled with lubricating oil including the internal pores of the bearing sleeve 8 (pores of the porous body tissue). The oil level of the lubricating oil is always maintained in the seal space S.
動圧軸受装置１の回転部材３（軸部２）が回転すると、軸受スリーブ８の内周面８ａのラジアル軸受面となる上下２つの領域は、それぞれ軸部２の外周面２ａとラジアル軸受隙間を介して対向する。そして、軸部２の回転に伴い、上記ラジアル軸受隙間に満たされた潤滑油が動圧作用を発生し、その圧力によって軸部２がラジアル方向に回転自在に非接触支持される。これにより、回転部材３をラジアル方向に回転自在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。また、ハウジング７の樹脂部７ａ２の上側端面７ｂ１と、軸部２と一体に成形されたハブ部９の下側端面９ａ１との間にはスラスト軸受隙間が形成されており、回転部材３の回転に伴い、上記スラスト軸受隙間に満たされた潤滑油が動圧作用を発生し、その圧力によって回転部材３がスラスト方向に回転自在に非接触支持される。これにより、回転部材３をスラスト方向に回転自在に非接触支持するスラスト軸受部Ｔ１が構成される。同様に、軸受スリーブ８の下側端面８ｃと軸部２のフランジ部１０の上側端面１０ａとの間にスラスト軸受隙間が形成され、このスラスト軸受隙間に潤滑油の動圧作用が生じて回転部材３をスラスト方向に非接触支持する第２スラスト軸受部Ｔ２が形成される。 When the rotating member 3 (shaft portion 2) of the hydrodynamic bearing device 1 is rotated, the upper and lower two regions that become the radial bearing surface of the inner peripheral surface 8a of the bearing sleeve 8 are respectively separated from the outer peripheral surface 2a of the shaft portion 2 and the radial bearing gap. Opposite through. As the shaft portion 2 rotates, the lubricating oil filled in the radial bearing gap generates a dynamic pressure action, and the shaft portion 2 is supported in a non-contact manner in the radial direction by the pressure. Thereby, the first radial bearing portion R1 and the second radial bearing portion R2 that support the rotating member 3 in a non-contact manner so as to be rotatable in the radial direction are configured. A thrust bearing gap is formed between the upper end surface 7 b 1 of the resin portion 7 a 2 of the housing 7 and the lower end surface 9 a 1 of the hub portion 9 formed integrally with the shaft portion 2, and the rotation of the rotating member 3. Accordingly, the lubricating oil filled in the thrust bearing gap generates a dynamic pressure action, and the rotating member 3 is supported in a non-contact manner so as to be rotatable in the thrust direction by the pressure. As a result, a thrust bearing portion T1 that supports the rotating member 3 in a non-contact manner so as to be rotatable in the thrust direction is configured. Similarly, a thrust bearing gap is formed between the lower end face 8c of the bearing sleeve 8 and the upper end face 10a of the flange portion 10 of the shaft portion 2, and the dynamic pressure action of the lubricating oil is generated in the thrust bearing gap, so that the rotating member A second thrust bearing portion T2 is formed to support 3 in the thrust direction in a non-contact manner.
このように、本実施形態では、ハウジング７の、モータブラケット６や軸受スリーブ８等の金属製部材が固定される固定面７ｄ１、７ｄ２を含む部分を金属部７ａ１で構成するとともに、動圧溝７ｂ１１を形成したスラスト軸受面を含む部分を樹脂部７ａ２で構成した。これにより、ハウジング７と金属製の軸受スリーブ８やモータブラケット６との固定強度を高め、例えば携帯型情報機器等に要求される高い耐衝撃特性を動圧軸受装置１に付与することができる。もちろん、両者を接着により固定する場合には、高い接着強度が得られると共に、接着力確保のための固定面７ｄ１、７ｄ２の表面処理や動圧溝７ｂ１１の電解加工などの後加工を省略して、ハウジング７の製造コストを大幅に低減できる。 As described above, in this embodiment, the portion of the housing 7 including the fixing surfaces 7d1 and 7d2 to which the metal members such as the motor bracket 6 and the bearing sleeve 8 are fixed is configured by the metal portion 7a1 and the dynamic pressure groove 7b11. The portion including the thrust bearing surface on which the is formed is constituted by the resin portion 7a2. Thereby, the fixing strength between the housing 7 and the metal bearing sleeve 8 or the motor bracket 6 can be increased, and high impact resistance characteristics required for, for example, a portable information device can be imparted to the dynamic pressure bearing device 1. Of course, when both are fixed by bonding, high adhesive strength is obtained, and post-processing such as surface treatment of the fixing surfaces 7d1 and 7d2 and electrolytic processing of the dynamic pressure groove 7b11 for securing the adhesive force is omitted. The manufacturing cost of the housing 7 can be greatly reduced.
以上、本発明の第１の実施形態を説明したが、本発明は、この実施形態に限定されるものではない。 The first embodiment of the present invention has been described above, but the present invention is not limited to this embodiment.
上記第１の実施形態では、ハウジング７の開口部７ｂを構成する樹脂部７ａ２の上側端面７ｂ１に動圧溝７ｂ１１を有するスラスト軸受面を設けるとともに（スラスト軸受部Ｔ１）、軸受スリーブ８の下側端面８ｃに動圧溝８ｃ１を有するスラスト軸受面を設けるようにしていたが（スラスト軸受部Ｔ２）、本発明は、スラスト軸受部Ｔ１のみを設けた動圧軸受装置にも同様に適用することができる。この場合、軸部２は、フランジ部１０を有しないストレートな形状になる。したがって、ハウジング７は、底部７ｃを側部７ａと一体に形成した有底円筒形の形態にすることができる。 In the first embodiment, a thrust bearing surface having a dynamic pressure groove 7b11 is provided on the upper end surface 7b1 of the resin portion 7a2 constituting the opening 7b of the housing 7 (thrust bearing portion T1), and the lower side of the bearing sleeve 8 Although the thrust bearing surface having the dynamic pressure groove 8c1 is provided on the end surface 8c (thrust bearing portion T2), the present invention can be similarly applied to a dynamic pressure bearing device provided with only the thrust bearing portion T1. it can. In this case, the shaft portion 2 has a straight shape without the flange portion 10. Therefore, the housing 7 can have a bottomed cylindrical shape in which the bottom portion 7c is formed integrally with the side portion 7a.
また、上記第１の実施形態では、軸受スリーブ８を、接着により、ハウジング７の側部７ａの固定面７ｄ２に固定するようにしていたが、例えば圧入や、超音波溶着など、接着以外の固定手段による固定で、軸受スリーブ８とハウジング７の間に充分な固定力が得られる場合には、特にハウジング７の固定面７ｄ２を含む部分を金属材料で形成する必要はない。 In the first embodiment, the bearing sleeve 8 is fixed to the fixing surface 7d2 of the side portion 7a of the housing 7 by bonding. However, for example, press-fitting or ultrasonic welding or the like is used for fixing other than bonding. When a sufficient fixing force is obtained between the bearing sleeve 8 and the housing 7 by fixing by means, it is not necessary to form a portion including the fixing surface 7d2 of the housing 7 with a metal material.
図５は、第２の実施形態に係る動圧軸受装置１１を示している。この実施形態において、軸部（回転部材）１２は、その下端に一体または別体に設けられたフランジ部２０を備えている。また、ハウジング１７は、円筒状の側部１７ａと、側部１７ａの下端部に固定された底部材１７ｃとを備えている。ハウジング１７の側部１７ａの上端部内周にはシール部材１３が固定される。ハウジング１７の底部材１７ｃの内底面１７ｃ１には、図示は省略するが、例えばスパイラル形状の動圧溝が形成されるとともに、軸受スリーブ１８の下側端面１８ｃにも、同様の形状の動圧溝が形成される。そして、軸受スリーブ１８の下側端面１８ｃと軸部１２のフランジ部２０の上側端面２０ａとの間にスラスト軸受部Ｔ１１が形成され、ハウジング１７の底部材１７ｃの内底面１７ｃ１とフランジ部２０の下側端面２０ｂとの間にスラスト軸受部Ｔ１２が形成される。 FIG. 5 shows a hydrodynamic bearing device 11 according to the second embodiment. In this embodiment, the shaft portion (rotating member) 12 includes a flange portion 20 provided integrally or separately at the lower end thereof. The housing 17 includes a cylindrical side portion 17a and a bottom member 17c fixed to the lower end portion of the side portion 17a. A seal member 13 is fixed to the inner periphery of the upper end portion of the side portion 17a of the housing 17. Although not shown in the drawings, the inner bottom surface 17c1 of the bottom member 17c of the housing 17 is formed with, for example, a spiral-shaped dynamic pressure groove, and the lower end surface 18c of the bearing sleeve 18 has a similar shape. Is formed. A thrust bearing portion T11 is formed between the lower end surface 18c of the bearing sleeve 18 and the upper end surface 20a of the flange portion 20 of the shaft portion 12, and the bottom surface 17c1 of the bottom member 17c of the housing 17 and the flange portion 20 A thrust bearing portion T12 is formed between the side end surface 20b.
この実施形態において、ハウジング１７の側部１７ａは、金属材料で円筒状に形成されており、該側部１７ａの外周および内周にそれぞれ固定面１７ｄ１および固定面１７ｄ２が形成されている。固定面１７ｄ１には、図示は省略するが、金属製のモータブラケットが例えば接着や圧入等の手段で固定され、固定面１７ｄ２には、金属製の軸受スリーブ１８が例えば接着等の手段で固定される。動圧溝を有する底部材１７ｃは、樹脂材料で型成形され、例えば超音波溶着等の手段で側部１７ａの下端部に固定される。また、シール部材１３は、金属材料又は樹脂材料で形成される。前者の場合、シール部材１３は接着等の手段で側部１７ａに固定され、後者の場合、シール部材１３は超音波溶着等の手段で側部１７ａに固定される。なお、これ以外の事項については、前記第１の実施形態に準じるので、以下重複説明を省略する。 In this embodiment, the side portion 17a of the housing 17 is formed of a metal material in a cylindrical shape, and a fixed surface 17d1 and a fixed surface 17d2 are formed on the outer periphery and the inner periphery of the side portion 17a, respectively. Although not shown in the drawings, the metal motor bracket is fixed to the fixed surface 17d1 by means of, for example, adhesion or press fitting, and the metal bearing sleeve 18 is fixed to the fixed surface 17d2, for example, by means of adhesion or the like. The The bottom member 17c having a dynamic pressure groove is molded with a resin material and fixed to the lower end portion of the side portion 17a by means such as ultrasonic welding. Further, the seal member 13 is formed of a metal material or a resin material. In the former case, the seal member 13 is fixed to the side portion 17a by means such as adhesion, and in the latter case, the seal member 13 is fixed to the side portion 17a by means such as ultrasonic welding. Since matters other than this are the same as those in the first embodiment, redundant description will be omitted.
１、１１ 動圧軸受装置
２、１２ 軸部
３ 回転部材
４ ステータコイル
５ ロータマグネット
６ モータブラケット
７、１７ ハウジング
７ａ、１７ａ 側部
７ａ１ 金属部
７ａ２ 樹脂部
７ｂ 開口部
７ｂ１ 上側端面
７ｂ１１ 動圧溝
７ｃ 底部
７ｄ１、７ｄ２、１７ｄ１、１７ｄ２ 固定面
８、１８ 軸受スリーブ
８ａ１ 動圧溝
８ｃ 下側端面
８ｃ１ 動圧溝
９ ハブ部
９ａ 主部
９ｂ 筒状部
９ｃ ディスク搭載面
９ｄ 鍔部
１０、２０ フランジ部
１７ｃ 底部材
１７ｃ１ 内底面
Ｒ１、Ｒ２ ラジアル軸受部
Ｔ１、Ｔ２、Ｔ１１、Ｔ１２ スラスト軸受部
DESCRIPTION OF SYMBOLS 1, 11 Dynamic pressure bearing apparatus 2, 12 Shaft part 3 Rotating member 4 Stator coil 5 Rotor magnet 6 Motor bracket 7, 17 Housing 7a, 17a Side part 7a1 Metal part 7a2 Resin part 7b Opening part 7b1 Upper end surface 7b11 Dynamic pressure groove 7c Bottom portion 7d1, 7d2, 17d1, 17d2 Fixed surface 8, 18 Bearing sleeve 8a1 Dynamic pressure groove 8c Lower end surface 8c1 Dynamic pressure groove 9 Hub portion 9a Main portion 9b Cylindrical portion 9c Disk mounting surface 9d Gutter portion 10, 20 Flange portion 17c Bottom member 17c1 Inner bottom surface R1, R2 Radial bearing portion T1, T2, T11, T12 Thrust bearing portion
Claims (2)
前記ハウジングは、円筒状の側部と、該側部の一端側に位置する開口部と、前記側部の他端側に位置する底部とを備えるもので、前記スラスト軸受部を構成し、かつ動圧溝が形成されたスラスト軸受面と、他の金属製部材が接着で固定される接着固定面、および前記回転部材との間に前記潤滑油のシール空間を形成するテーパ状の外壁を有し、
前記スラスト軸受面は、前記側部の前記開口部側の端面に形成され、前記接着固定面は、前記側部の前記底部側の外周面に形成され、前記テーパ状の外壁は、前記側部の前記開口部側の外周面に形成され、
前記側部の、前記スラスト軸受面を含む部分を樹脂材料で形成し、前記接着固定面を含む部分を金属材料で形成したことを特徴とする動圧軸受装置。 A housing, a bearing sleeve fixed inside the housing, a rotating member that rotates relative to the bearing sleeve and the housing, and a lubricating oil generated in a radial bearing gap between the rotating member and the bearing sleeve. A radial bearing portion that supports the rotating member in a radial direction in a non-contact manner by a dynamic pressure action, and a dynamic pressure action of lubricating oil generated in a thrust bearing gap between the rotating member and the housing prevents the rotating member from being moved in a thrust direction. In the hydrodynamic bearing device provided with a thrust bearing portion for contact and support,
The housing includes a cylindrical side portion, an opening portion located on one end side of the side portion, and a bottom portion located on the other end side of the side portion, constituting the thrust bearing portion, and A thrust bearing surface in which a dynamic pressure groove is formed, an adhesive fixing surface to which another metal member is fixed by adhesion , and a tapered outer wall that forms a sealing space for the lubricating oil are provided between the rotating member and the thrust bearing surface. And
The thrust bearing surface is formed on an end surface of the side portion on the opening portion side, the adhesive fixing surface is formed on an outer peripheral surface of the side portion on the bottom side, and the tapered outer wall is formed on the side portion. Formed on the outer peripheral surface of the opening side of
The hydrodynamic bearing device, wherein a portion of the side portion including the thrust bearing surface is formed of a resin material, and a portion including the adhesive fixing surface is formed of a metal material.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004149632A JP4515151B2 (en) | 2004-05-19 | 2004-05-19 | Hydrodynamic bearing device |
| CN2005800100668A CN1957184B (en) | 2004-03-30 | 2005-03-17 | Fluid dynamic pressure bearing device |
| PCT/JP2005/004822 WO2005098251A1 (en) | 2004-03-30 | 2005-03-17 | Dynamic pressure bearing device |
| US10/591,802 US7798721B2 (en) | 2004-03-30 | 2005-03-17 | Fluid dynamic bearing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004149632A JP4515151B2 (en) | 2004-05-19 | 2004-05-19 | Hydrodynamic bearing device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2005331034A JP2005331034A (en) | 2005-12-02 |
| JP4515151B2 true JP4515151B2 (en) | 2010-07-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004149632A Expired - Fee Related JP4515151B2 (en) | 2004-03-30 | 2004-05-19 | Hydrodynamic bearing device |
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| Country | Link |
|---|---|
| JP (1) | JP4515151B2 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001065552A (en) * | 1999-08-26 | 2001-03-16 | Sankyo Seiki Mfg Co Ltd | Dynamic pressure bearing device |
| JP2003262217A (en) * | 2002-03-07 | 2003-09-19 | Nippon Densan Corp | Spindle motor and disk drive device equipped with the same |
| JP2003314537A (en) * | 2002-04-23 | 2003-11-06 | Sony Corp | Bearing unit, motor therewith, and electronic device |
| JP2004028165A (en) * | 2002-06-24 | 2004-01-29 | Ntn Corp | Fluid bearing device |
| JP2004245248A (en) * | 2003-02-10 | 2004-09-02 | Nippon Densan Corp | Bearing mechanism, motor, and disk driving device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08207790A (en) * | 1995-01-31 | 1996-08-13 | Jidosha Kiki Co Ltd | Rack supporting structure in steering system |
-
2004
- 2004-05-19 JP JP2004149632A patent/JP4515151B2/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001065552A (en) * | 1999-08-26 | 2001-03-16 | Sankyo Seiki Mfg Co Ltd | Dynamic pressure bearing device |
| JP2003262217A (en) * | 2002-03-07 | 2003-09-19 | Nippon Densan Corp | Spindle motor and disk drive device equipped with the same |
| JP2003314537A (en) * | 2002-04-23 | 2003-11-06 | Sony Corp | Bearing unit, motor therewith, and electronic device |
| JP2004028165A (en) * | 2002-06-24 | 2004-01-29 | Ntn Corp | Fluid bearing device |
| JP2004245248A (en) * | 2003-02-10 | 2004-09-02 | Nippon Densan Corp | Bearing mechanism, motor, and disk driving device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2005331034A (en) | 2005-12-02 |
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