JPH0870549A - Magnetic disk driver - Google Patents

Magnetic disk driver

Info

Publication number
JPH0870549A
JPH0870549A JP20386994A JP20386994A JPH0870549A JP H0870549 A JPH0870549 A JP H0870549A JP 20386994 A JP20386994 A JP 20386994A JP 20386994 A JP20386994 A JP 20386994A JP H0870549 A JPH0870549 A JP H0870549A
Authority
JP
Japan
Prior art keywords
hub
rotor yoke
magnetic disk
disk drive
sections
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Withdrawn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
JP20386994A
Other languages
Japanese (ja)
Inventor
Yutaka Ishizuka
豊 石塚
Shinji Ota
真司 太田
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.)
Nidec Sankyo Corp
Original Assignee
Nidec Sankyo Corp
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 Nidec Sankyo Corp filed Critical Nidec Sankyo Corp
Priority to JP20386994A priority Critical patent/JPH0870549A/en
Publication of JPH0870549A publication Critical patent/JPH0870549A/en
Withdrawn legal-status Critical Current

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  • Brushless Motors (AREA)
  • Motor Or Generator Frames (AREA)

Abstract

PURPOSE: To remove cutting oil, etc., remaining on an abutting face between a hub and a rotor yoke by washing under the condition that the hub and the rotor yoke is fixed to each other tightly by forming projecting and recessed sections on the abutting face. CONSTITUTION: A rotor yoke 2 abuts against radial projecting sections 9 of a hub 1 and is fixed by caulking at caulking sections for the hub 1 which are formed on the inner circumference of the rotor yoke 2. Therefore, the projecting sections 9 of the hub 1 which form an abutting face E against the rotor yoke abut against the rotor yoke 2 and thereby cavities 11 which are surrounded by side faces of the recessed sections 8 of the hub 1 and an upper face of the rotor yoke 2 are formed in the hub 1. After the rotor yoke 2 is tightly fixed to the hub 1, an inner part of the rotor yoke is chucked by a jig and necessary parts of the hub 1 are finished. The recessed and projecting sections 8, 9 are not given a finishing work by a lathe, etc. By this method, cutting coil, etc., which is remaining on the abutting face between the hub 1 and the rotor yoke 2 can be nearly completely removed by washing.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、磁気ディスク駆動装置
に関するもので、特に磁気ディスクを搭載して回転駆動
するためのハブに関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive device, and more particularly to a hub for mounting and rotating a magnetic disk.

【0002】[0002]

【従来の技術】従来、この種の磁気ディスク駆動装置と
しては、図4及び図5に示すようなものがあった。即
ち、図4に示すように(特開平5−49223号公報記
載)、図示しない磁気ディスクが搭載されるハブ1と、
このハブ1に固着されたロータヨーク2と、このロータ
ヨーク2に装着された駆動マグネット3と、この駆動マ
グネット3に対向配置されたステータ7とを備え、上記
駆動マグネット3と上記ステータ7との相対回転により
上記ハブ1が回転駆動されてなる磁気ディスク駆動装置
Aがあった。
2. Description of the Related Art Conventionally, as magnetic disk drive devices of this type, there have been those shown in FIGS. That is, as shown in FIG. 4 (described in JP-A-5-49223), a hub 1 on which a magnetic disk (not shown) is mounted,
A rotor yoke 2 fixed to the hub 1, a drive magnet 3 attached to the rotor yoke 2, and a stator 7 arranged to face the drive magnet 3 are provided, and the drive magnet 3 and the stator 7 rotate relative to each other. Thus, there is a magnetic disk drive device A in which the hub 1 is driven to rotate.

【0003】上記、磁気ディスク駆動装置Aにおいて、
ハブ1におけるロータヨーク2との当接面Eは、ロータ
ヨーク2と平面同士で当接し、固着されていた。このた
め、その状態で切削油を用いて仕上げ加工をすると、上
記ハブ1とロータヨーク2の当接面Eに残留した切削油
等は、洗浄しても完全に除去できず、その油がモータ駆
動中にしみ出して、ダストの原因となる等、磁気ディス
ク駆動装置の信頼性を低下させる要因となっていた。
In the above magnetic disk drive A,
The contact surface E of the hub 1 with the rotor yoke 2 is in contact with and fixed to the rotor yoke 2 in a plane-to-plane relationship. For this reason, if a finishing process is performed using cutting oil in that state, the cutting oil and the like remaining on the contact surface E between the hub 1 and the rotor yoke 2 cannot be completely removed by washing, and the oil is driven by the motor. It has been a factor that reduces the reliability of the magnetic disk drive device, such as exuding inside and causing dust.

【0004】そこで、これを避けるため、ハブ1とロー
タヨーク2は別々に完成体まで加工を施した後、精密洗
浄を行い、そして両者を固着する方法もある。しかし、
この方法によれば、図5に示すように、ハブ1とロータ
ヨーク2に嵌合隙間Cがあるため、回転軸に対するロー
タヨーク内径Dの振れが大きくなり、ハブ1とロータヨ
ーク2と駆動マグネット3で構成されるロータのダイナ
ミックバランスが悪化して磁気ディスク駆動装置に悪影
響を及ぼしていた。
Therefore, in order to avoid this, there is also a method in which the hub 1 and the rotor yoke 2 are separately processed to a finished product, then precision cleaning is performed, and then both are fixed. But,
According to this method, as shown in FIG. 5, since there is a fitting gap C between the hub 1 and the rotor yoke 2, the swing of the rotor yoke inner diameter D with respect to the rotating shaft becomes large, and the hub 1, the rotor yoke 2 and the drive magnet 3 are formed. The dynamic balance of the rotor is deteriorated and the magnetic disk drive is adversely affected.

【0005】また、従来のようにハブ1とロータヨーク
2が平面同士で当接していると、ハブ1を鋳造や焼結の
中間体(ブランク)で製作しても、ロータヨーク当接面
Eの平面度や回転軸6に対する直角度Bの精度が劣悪で
あり、どうしても上記ハブ1のロータヨーク当接面Eを
旋盤により加工せざるを得ず、生産性が低下しコスト高
の原因となっていた。
Further, when the hub 1 and the rotor yoke 2 are in contact with each other in a flat surface as in the conventional case, even if the hub 1 is manufactured by a casting or sintering intermediate body (blank), the flat surface of the rotor yoke contact surface E is obtained. The degree of accuracy and the accuracy of the squareness B with respect to the rotary shaft 6 are poor, and the rotor yoke contact surface E of the hub 1 is inevitably processed by a lathe, resulting in a decrease in productivity and an increase in cost.

【0006】[0006]

【発明が解決しようとする課題】したがって、上記従来
技術では、ハブとロータヨークが平面同士で当接し、固
着されていたため、仕上げ加工するときの切削油等が完
全には除去されず、磁気ディスク駆動装置の信頼性を低
下させていた。また、ハブとロータヨークを別々に完成
体まで加工し、精密洗浄を行い、両者を固着する方法に
よっても、ハブとロータヨークの嵌合隙間により、ロー
タのダイナミックバランスが悪化して磁気ディスク駆動
装置に悪影響を及ぼしていた。
Therefore, in the above-mentioned prior art, since the hub and the rotor yoke are in contact with each other and are fixed to each other, the cutting oil and the like at the time of finishing are not completely removed, and the magnetic disk drive. It reduced the reliability of the device. Also, by separately processing the hub and rotor yoke to a finished product, performing precision cleaning, and fixing them together, the fitting gap between the hub and rotor yoke deteriorates the dynamic balance of the rotor and adversely affects the magnetic disk drive. Was affecting.

【0007】本発明は、以上述べたような問題に対処し
てなされたものであり、ハブとロータヨークが固着され
た状態で仕上げ加工をしても、切削油等がほぼ完全に除
去できるようなハブの形状について提案し、もって信頼
性の高い磁気ディスク駆動装置を提供することを目的と
する。
The present invention has been made to solve the above-mentioned problems, and the cutting oil and the like can be almost completely removed even when finishing is performed with the hub and the rotor yoke fixed to each other. It is an object of the present invention to propose a hub shape and to provide a highly reliable magnetic disk drive device.

【0008】[0008]

【課題を解決するための手段】上記目的を達成するため
に、本発明は、磁気ディスクが搭載されるハブと、この
ハブに固着された磁性材からなるロータヨークと、この
ロータヨークに装着された駆動マグネットと、この駆動
マグネットに対向配置されたステータとを備え、駆動マ
グネットとステータとの相対回転により上記ハブが回転
駆動されてなる磁気ディスク駆動装置において、上記ハ
ブは上記ロータヨークと軸方向に対向する部位に略放射
状に形成された複数の凹凸部を有し、この凸部と上記ハ
ブとが当接していることを特徴とする。また、ハブに形
成された複数の凹凸部は、仕上げ加工が施されていない
ことを特徴とする。
In order to achieve the above object, the present invention provides a hub on which a magnetic disk is mounted, a rotor yoke made of a magnetic material fixed to the hub, and a drive mounted on the rotor yoke. In a magnetic disk drive device comprising a magnet and a stator arranged to face the drive magnet, and the hub is rotationally driven by relative rotation of the drive magnet and the stator, the hub opposes the rotor yoke in the axial direction. It is characterized in that it has a plurality of concavo-convex portions formed in a substantially radial shape at the portion, and the convex portions are in contact with the hub. Further, the plurality of uneven portions formed on the hub are not subjected to finishing processing.

【0009】[0009]

【作用】本発明の構成によれば、ハブとロータヨークの
当接面に凹凸部を設けることにより、ハブとロータヨー
クが固着された状態で上記当接面に切削油等が残留して
いても、洗浄によりほぼ完全に除去できるため、ハブの
中間体にロータヨークをカシメ固着した後、仕上げ切削
加工が可能となる。このため、電動機の回転体のダイナ
ミックバランスがきわめて向上する。
According to the structure of the present invention, by providing the concavo-convex portion on the contact surface between the hub and the rotor yoke, even if cutting oil or the like remains on the contact surface with the hub and the rotor yoke fixed to each other, Since the rotor yoke can be almost completely removed by cleaning, the rotor yoke can be caulked and fixed to the intermediate body of the hub, and then finish cutting can be performed. Therefore, the dynamic balance of the rotating body of the electric motor is significantly improved.

【0010】また、切削油等、磁気ディスク駆動装置に
有害な物質の残留がなくなるため、信頼性の高い磁気デ
ィスク駆動装置を得ることができる。更に、ハブのロー
タヨーク当接面は切削加工が不要となるので、工程が簡
略化され、生産性が大幅に向上し、安価大量に電動機を
供給することができる。
Further, since a substance harmful to the magnetic disk drive device such as cutting oil does not remain, a highly reliable magnetic disk drive device can be obtained. Further, since the rotor yoke contact surface of the hub does not need to be cut, the process is simplified, the productivity is greatly improved, and it is possible to supply a large amount of electric motors at low cost.

【0011】[0011]

【実施例】図1〜図3は本発明の実施例を示すものであ
る。従来技術である図4及び図5と同じ機能、作用を有
するものについては、同一符号を付けて説明する。以
下、図面を参照して本発明の実施例を詳細に説明する。
1 to 3 show an embodiment of the present invention. Components having the same functions and actions as those of the conventional arts shown in FIGS. 4 and 5 are described with the same reference numerals. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

【0012】図1に示される、本発明に係わる磁気ディ
スク駆動装置Aは、図示しない磁気ディスクが搭載され
るハブ1と、このハブ1に固着された磁性材からなるロ
ータヨーク2と、このロータヨーク2に装着された駆動
マグネット3と、この駆動マグネット3に対向配置され
たステータ7とを備え、駆動マグネット3とステータ7
との相対回転により上記ハブ1が回転駆動されて構成さ
れている。なお、駆動マグネット3はハブ1のロータヨ
ーク2の内周面に固着されており、ハブ1と回転軸6の
間にはボールベアリング5a,5bの如く、軸受手段が
介在されている。また、ステータ7はフレーム4に保持
される。
A magnetic disk drive A according to the present invention shown in FIG. 1 has a hub 1 on which a magnetic disk (not shown) is mounted, a rotor yoke 2 made of a magnetic material fixed to the hub 1, and a rotor yoke 2 The drive magnet 3 mounted on the drive magnet 3 and the stator 7 arranged to face the drive magnet 3.
The hub 1 is rotationally driven by relative rotation with respect to. The drive magnet 3 is fixed to the inner peripheral surface of the rotor yoke 2 of the hub 1, and bearing means such as ball bearings 5a and 5b is interposed between the hub 1 and the rotary shaft 6. The stator 7 is held by the frame 4.

【0013】上記、磁気ディスク駆動装置Aにおいて、
ハブ1のロータヨーク当接面Eには、図2に示すよう
に、ロータヨーク2と軸方向に対向する部位に、放射状
に複数の凹凸部8,9を形成し、上記凹部8凸部9間に
は、段差を設ける。上記ハブ1は焼結或いは鍛造で中間
体を製作するが、この中間体形成時に、上記凹凸部8,
9を形成する。上記ハブ1のロータヨーク当接面Eは複
数の凸部9のみを上記中間体において、面打ちと呼ばれ
る平面度を改善する塑性加工を施す。ロータヨーク2は
上記ハブ1に、ハブ1の上記放射状の凸部9に当接し、
ロータヨーク2の内周部分に形成されているハブ1のカ
シメ部10で、カシメにより固着される。よって、図3
に示すように、上記ハブ1のロータヨーク当接面Eであ
る凸部9がロータヨーク2に当接し、上記ハブ1の凹部
8は、ハブ1の凸部9側面とロータヨーク2上面に囲ま
れた空洞11が形成される。ハブ1にロータヨーク2が
固着された後、ロータヨーク内径Dを治具でチャック
し、ハブ1の必要部分が仕上げ切削加工される。また、
上記、凹凸部8,9は旋盤等による仕上げ加工が施され
ていない。なお、上記、凹部8凸部間9の段差は0.2
mm〜1mmとする。
In the above magnetic disk drive A,
As shown in FIG. 2, on the rotor yoke contact surface E of the hub 1, a plurality of uneven portions 8 and 9 are radially formed at a portion facing the rotor yoke 2 in the axial direction, and between the concave portions 8 and the convex portions 9. Provides a step. The hub 1 is manufactured by sintering or forging to form an intermediate body. When the intermediate body is formed, the uneven portion 8,
9 is formed. The rotor yoke abutting surface E of the hub 1 is subjected to plastic working called flattening in order to improve the flatness in the intermediate body only with the plurality of convex portions 9. The rotor yoke 2 is brought into contact with the hub 1 and the radial projection 9 of the hub 1,
At the caulking portion 10 of the hub 1 formed on the inner peripheral portion of the rotor yoke 2, the hub 1 is fixed by caulking. Therefore, FIG.
As shown in FIG. 3, the convex portion 9 which is the rotor yoke contact surface E of the hub 1 abuts the rotor yoke 2, and the concave portion 8 of the hub 1 is a cavity surrounded by the side surface of the convex portion 9 of the hub 1 and the upper surface of the rotor yoke 2. 11 is formed. After the rotor yoke 2 is fixed to the hub 1, the inner diameter D of the rotor yoke is chucked with a jig, and a necessary portion of the hub 1 is finish-cut. Also,
The uneven portions 8 and 9 are not finished by a lathe or the like. In addition, the step difference between the concave portion 8 and the convex portion 9 is 0.2
mm to 1 mm.

【0014】上記のように、ハブ1とロータヨーク2の
当接面に凹凸部8,9を設けることにより、ハブ1とロ
ータヨーク2が固着された状態で、上記当接面に切削油
等が残留していても、洗浄によりほぼ完全に除去できる
ため、ハブ1の中間体にロータヨーク2をカシメ部10
でカシメ固着した後、仕上げ切削加工が可能となる。こ
の際、ロータヨーク内径Dを治具によりチャックし、ハ
ブ1の必要部分を加工することにより、回転軸6に対す
るロータヨーク内径Dの振れが極小となる。また、ハブ
1のロータヨーク当接面Eは複数の凸部9のみを中間体
において、面打ちと呼ばれる平面度を改善する塑性加工
を施すことになるので、ロータヨーク2が当接するハブ
1の凸部9の包絡線における平面度が極めて改善され
る。
As described above, by providing the concavo-convex portions 8 and 9 on the contact surface between the hub 1 and the rotor yoke 2, cutting oil or the like remains on the contact surface while the hub 1 and the rotor yoke 2 are fixed. However, since the rotor yoke 2 can be almost completely removed by washing, the rotor yoke 2 is attached to the intermediate body of the hub 1 by the caulking portion 10.
After caulking and fixing, it is possible to finish cutting. At this time, the inner diameter D of the rotor yoke is chucked by a jig, and the necessary portion of the hub 1 is machined to minimize the swing of the inner diameter D of the rotor yoke with respect to the rotating shaft 6. Further, since the rotor yoke contact surface E of the hub 1 is subjected to plastic working called flattening for improving the flatness only with the plurality of protrusions 9 in the intermediate body, the protrusions of the hub 1 with which the rotor yoke 2 abuts. The flatness at the envelope of 9 is significantly improved.

【0015】[0015]

【発明の効果】以上述べたように本発明によれば、ハブ
とロータヨークの当接面に凹凸部を設けることにより、
上記当接面の切削油等を、洗浄により、ほぼ完全に除去
でき、よって、ハブにロータヨーク固着後、仕上げ切削
加工が可能となるため、電動機の回転体のダイナミック
バランスがきわめて向上し、信頼性の高い磁気ディスク
駆動装置を得ることができる。また、切削油等、磁気デ
ィスク駆動装置に有害な物質の残留がなくなるため、信
頼性の高い磁気ディスク駆動装置を得ることができる。
更に、ハブのロータヨーク当接面は切削加工が不要とな
るので、工程が簡略化され、生産性が大幅に向上し、安
価大量に電動機を供給することができる。
As described above, according to the present invention, by providing the uneven portion on the contact surface between the hub and the rotor yoke,
The cutting oil on the abutment surface can be almost completely removed by washing, and therefore, finish cutting can be performed after the rotor yoke is fixed to the hub, so that the dynamic balance of the rotating body of the electric motor is significantly improved and the reliability is improved. It is possible to obtain a high-performance magnetic disk drive device. Further, since a substance harmful to the magnetic disk drive device such as cutting oil does not remain, a highly reliable magnetic disk drive device can be obtained.
Further, since the rotor yoke contact surface of the hub does not need to be cut, the process is simplified, the productivity is greatly improved, and it is possible to supply a large amount of electric motors at low cost.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の実施例を示す磁気ディスク駆動装置の
要部断面図である。
FIG. 1 is a cross-sectional view of essential parts of a magnetic disk drive device showing an embodiment of the present invention.

【図2】本発明の実施例を示す磁気ディスク駆動装置の
ハブの底面図である。
FIG. 2 is a bottom view of the hub of the magnetic disk drive according to the embodiment of the present invention.

【図3】本発明の実施例を示す磁気ディスク駆動装置の
側面図である。
FIG. 3 is a side view of a magnetic disk drive device showing an embodiment of the present invention.

【図4】従来の実施例を示す磁気ディスク駆動装置の要
部断面図である。
FIG. 4 is a cross-sectional view of a main part of a magnetic disk drive device showing a conventional embodiment.

【図5】従来の実施例を示す磁気ディスク駆動装置のハ
ブとロータヨークの要部断面図である。
FIG. 5 is a cross-sectional view of essential parts of a hub and a rotor yoke of a magnetic disk drive device showing a conventional embodiment.

【符号の説明】[Explanation of symbols]

1 ハブ 2 ロータヨーク 3 駆動マグネット 7 ステータ 8 凹部 9 凸部 A 磁気ディスク駆動装置 1 Hub 2 Rotor Yoke 3 Drive Magnet 7 Stator 8 Recess 9 Recess 9 A Magnetic Disk Drive

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 磁気ディスクが搭載されるハブと、この
ハブに固着された磁性材からなるロータヨークと、この
ロータヨークに装着された駆動マグネットと、この駆動
マグネットに対向配置されたステータとを備え、駆動マ
グネットとステータとの相対回転により上記ハブが回転
駆動されてなる磁気ディスク駆動装置において、上記ハ
ブは上記ロータヨークと軸方向に対向する部位に略放射
状に形成された複数の凹凸部を有し、この凸部と上記ハ
ブとが当接していることを特徴とする磁気ディスク駆動
装置。
1. A hub on which a magnetic disk is mounted, a rotor yoke made of a magnetic material fixed to the hub, a drive magnet mounted on the rotor yoke, and a stator arranged to face the drive magnet. In a magnetic disk drive device in which the hub is rotationally driven by relative rotation of a drive magnet and a stator, the hub has a plurality of uneven portions formed in a substantially radial shape at a portion facing the rotor yoke in the axial direction, A magnetic disk drive device characterized in that the convex portion and the hub are in contact with each other.
【請求項2】 ハブに形成された複数の凹凸部は、仕上
げ加工が施されていないことを特徴とする請求項1記載
の磁気ディスク駆動装置。
2. The magnetic disk drive device according to claim 1, wherein the plurality of concave and convex portions formed on the hub are not finished.
JP20386994A 1994-08-29 1994-08-29 Magnetic disk driver Withdrawn JPH0870549A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP20386994A JPH0870549A (en) 1994-08-29 1994-08-29 Magnetic disk driver

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP20386994A JPH0870549A (en) 1994-08-29 1994-08-29 Magnetic disk driver

Publications (1)

Publication Number Publication Date
JPH0870549A true JPH0870549A (en) 1996-03-12

Family

ID=16481062

Family Applications (1)

Application Number Title Priority Date Filing Date
JP20386994A Withdrawn JPH0870549A (en) 1994-08-29 1994-08-29 Magnetic disk driver

Country Status (1)

Country Link
JP (1) JPH0870549A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8223455B2 (en) 2006-03-10 2012-07-17 Nidec Corporation Rotor hub, motor, and disk driving device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8223455B2 (en) 2006-03-10 2012-07-17 Nidec Corporation Rotor hub, motor, and disk driving device

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