JPH01198261A - Composite outer rotor for loading magnetic disk - Google Patents
Composite outer rotor for loading magnetic diskInfo
- Publication number
- JPH01198261A JPH01198261A JP63020289A JP2028988A JPH01198261A JP H01198261 A JPH01198261 A JP H01198261A JP 63020289 A JP63020289 A JP 63020289A JP 2028988 A JP2028988 A JP 2028988A JP H01198261 A JPH01198261 A JP H01198261A
- Authority
- JP
- Japan
- Prior art keywords
- outer rotor
- magnetic
- magnetic disk
- cylinder
- shielding cylinder
- 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.)
- Pending
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 18
- 239000007769 metal material Substances 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims abstract description 7
- 238000000465 moulding Methods 0.000 claims description 14
- 230000002093 peripheral effect Effects 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 2
- 230000008878 coupling Effects 0.000 abstract 1
- 238000010168 coupling process Methods 0.000 abstract 1
- 238000005859 coupling reaction Methods 0.000 abstract 1
- 230000008602 contraction Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- -1 1.5 iOz Chemical compound 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Landscapes
- Permanent Field Magnets Of Synchronous Machinery (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、磁気ディスク装置に内蔵される磁気ディスク
回転駆動モータに係り、磁気ディスク装着用ハブを兼用
したアウタロータに関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic disk rotation drive motor built into a magnetic disk device, and relates to an outer rotor that also serves as a hub for mounting a magnetic disk.
（従来の技術）
近年、磁気ディスク装置の小形化および大容量化が要請
されるに伴って、磁気ディスク回転駆動用モータとして
、例えば実開昭６１−４７６号公報に開示されているよ
うに、小形化が可能なアウタロータ形のブラシレスＤＣ
モータの普及が著しい。(Prior Art) In recent years, with the demand for smaller size and larger capacity magnetic disk drives, motors for driving rotation of magnetic disks have been developed, for example, as disclosed in Japanese Utility Model Application No. 61-476. Outer rotor type brushless DC that can be made smaller
Motors are becoming increasingly popular.
該アウタロータ形のＤＣモータは、第２図に示すように
、モータ基板３１上に固定軸３２を立設し、該固定軸３
２の回りに固定子３３を設け、該固定子３３を取り囲む
ようにアウタロータ３４が軸受３５．３５を介して固定
軸３２に回転自在に支持されている。該アウタロータ３
４は、磁気ディスク３６装着用のハブを兼用しており、
磁性ステンレス鋼等の磁性金属材料で形成され、その内
周面に永久磁石３７が装着されている。アウタロータ３
４を磁性金属材で形成するのは、永久磁石３７からの漏
洩磁束の発生を防止し、該ロータ３４に装着された磁気
ディスク３６に影響を与えないようにするためである。As shown in FIG. 2, the outer rotor type DC motor has a fixed shaft 32 erected on a motor board 31.
A stator 33 is provided around the rotor 2, and an outer rotor 34 is rotatably supported on the fixed shaft 32 via bearings 35, 35 so as to surround the stator 33. The outer rotor 3
4 also serves as a hub for mounting the magnetic disk 36,
It is made of a magnetic metal material such as magnetic stainless steel, and a permanent magnet 37 is attached to its inner peripheral surface. Outer rotor 3
4 is made of a magnetic metal material in order to prevent leakage magnetic flux from the permanent magnet 37 from occurring and to prevent it from affecting the magnetic disk 36 mounted on the rotor 34 .
３８はアウタロータ３４の底面部材であり、磁気ディス
ク３６が載置される。尚、磁気ディスク３６は、図示し
ないスペーサを介して積層、装着されて大容量化が図ら
れる。38 is a bottom member of the outer rotor 34, on which the magnetic disk 36 is placed. The magnetic disks 36 are stacked and attached via spacers (not shown) to increase the capacity.
上記アウタロータ形のＤＣモータによれば、固定子３３
をアウタロータ３４の内部に収納することができ小形化
を図ることができる。しかし、アウタロータ３４を形成
する材料として磁性金属材を使用しているため軽量化を
図ることができず、モータトルクがアウタロータ３４自
体の回転に相当取られ、固定子３３や永久磁石３７の小
形化延いてはモータ自体の小形化を阻害する要因となっ
ていた。According to the above outer rotor type DC motor, the stator 33
can be stored inside the outer rotor 34, making it possible to reduce the size. However, since a magnetic metal material is used as the material forming the outer rotor 34, it is not possible to reduce the weight, and the motor torque is equivalent to the rotation of the outer rotor 34 itself. In turn, this has become a factor that hinders miniaturization of the motor itself.
そこで、実開昭６１−１９２６６９号公報に開示され、
第３図に示すように、アルミニウム合金等の非磁性軽量
金属材で形成したアウタロータ本体４１の内面に磁性金
属材で形成した磁気遮蔽用筒体４２を嵌合により被着し
たアウタロータ３４ａが使用されるに及んでいる。Therefore, it was disclosed in Japanese Utility Model Application Publication No. 192669/1983,
As shown in FIG. 3, an outer rotor 34a is used in which a magnetic shielding cylinder 42 made of a magnetic metal material is fitted onto the inner surface of an outer rotor main body 41 made of a non-magnetic lightweight metal material such as an aluminum alloy. It extends to all
（発明が解決しようとする課題）
しかしながら、かかる複合構造のアウタロータ３４ａに
おいては、アウタロータ本体４１及び磁気遮蔽用筒体４
２を高精度に加工しなければならない。(Problem to be Solved by the Invention) However, in the outer rotor 34a having such a composite structure, the outer rotor main body 41 and the magnetic shielding cylinder 4
2 must be processed with high precision.
特に、この種のモータは小形化が要請されているため、
磁気遮蔽用筒体４２及びアウタロータ本体４１の磁気デ
ィスク装着面を形成する側壁部の厚さを１ ｍｍ程度あ
るいはそれ以下にすることが望まれており、加工が極め
て困難である。また、アウタロータ本体４１と磁気遮蔽
用筒体４２との嵌合に当っても慎重を要し、専用治具や
組立装置を必要とし、生産性の低下、加工コストの上昇
を余儀なくされていた。In particular, this type of motor is required to be smaller.
It is desired that the thickness of the side wall portion forming the magnetic disk mounting surface of the magnetic shielding cylinder 42 and the outer rotor main body 41 be approximately 1 mm or less, which is extremely difficult to process. Further, fitting the outer rotor main body 41 and the magnetic shielding cylinder 42 requires care, and requires special jigs and assembly equipment, which inevitably lowers productivity and increases processing costs.
本発明はかかる問題点に鑑みなされたもので、アウタロ
ータ本体の側壁部の厚さの大小に拘わらず、製作容易な
磁気ディスク装着用複合アウタロータを提供することを
目的とする。The present invention has been made in view of such problems, and an object of the present invention is to provide a composite outer rotor for mounting a magnetic disk that is easy to manufacture regardless of the thickness of the side wall portion of the outer rotor main body.
（課題を解決するための手段）
上記目的を達成するためになされた本発明の複合アウタ
ロータは、磁気ディスク回転駆動モークのアウタロータ
であって、磁気ディスクが装着される円筒状アウタロー
タ本体の内周面に磁気遮蔽用筒体が被着された複合アウ
タロータにおいて、前記アウタロータ本体は非磁性軽量
金属材により熱間成形されると共に成形後の冷却に伴う
収縮によって磁気遮蔽用筒体にしまり嵌め結合しており
、前記筒体とアウタロータ本体との間にアウタロータ本
体の収縮が前記筒体によって過度に拘束されるのを緩和
するための拘束緩和層が介装されていることを発明の構
成とするものである。(Means for Solving the Problems) A composite outer rotor of the present invention, which has been made to achieve the above object, is an outer rotor of a magnetic disk rotation drive moke, and the inner circumferential surface of a cylindrical outer rotor body to which a magnetic disk is mounted. In a composite outer rotor in which a magnetic shielding cylinder is attached to the outer rotor, the outer rotor main body is hot-formed from a non-magnetic lightweight metal material and is tightly fitted and coupled to the magnetic shielding cylinder by shrinkage due to cooling after molding. The present invention is characterized in that a restraint relieving layer is interposed between the cylindrical body and the outer rotor body to relieve the shrinkage of the outer rotor body from being excessively restrained by the cylindrical body. be.
（′実施例）
以下、本発明の磁気ディスク装着用複合アウタロータを
その製造方法と共に説明する。('Example) Hereinafter, the composite outer rotor for mounting a magnetic disk of the present invention will be described together with its manufacturing method.
第１図は本発明に係る複合アウタロータ１であり、円筒
状アウタロータ本体２の内周面に磁気遮蔽用筒体３が被
着されている。FIG. 1 shows a composite outer rotor 1 according to the present invention, in which a magnetic shielding cylinder 3 is attached to the inner peripheral surface of a cylindrical outer rotor main body 2. As shown in FIG.
前記アウタロータ本体２は磁気遮蔽用筒体３よりも熱膨
張率の大きいｉｌ：磁性軽量金属材（例えば、Ａ３０５
６． Ａ６０６Ｌ’ Ａ Ｄ ＣＩＯ，Ａ Ｄ Ｃ１２
等のアルミニウム合金、チタン合金）が熱開成形により
一体成形されたものである。The outer rotor main body 2 is made of a magnetic lightweight metal material (for example, A305
6. A606L' A D CIO, A D C12
Aluminum alloys, titanium alloys, etc.) are integrally formed by thermal open molding.
一方、磁気遮蔽用筒体３は磁性ステンレス（例えば５Ｕ
Ｓ４１６）等の磁性金属材で形成されており、アウタロ
ータ本体２の成形後の冷却に伴う収縮によってアウタロ
ータ本体２にしまり嵌め結合されている。On the other hand, the magnetic shielding cylinder 3 is made of magnetic stainless steel (for example, 5U
It is made of a magnetic metal material such as S416), and is tightly fitted and coupled to the outer rotor body 2 by contraction as the outer rotor body 2 cools after molding.
また、アウタロータ本体２と磁気遮蔽用筒体３との間に
は、アウタロータ本体２の成形後の収縮が前記筒体３に
よって過度に拘束されるのを緩和し、アウタロータ本体
２の側壁部にクランクが入るのを防止するための拘束緩
和層４が介装されている。該拘束緩和Ｎ４は、例えばＡ
Ａｚ Ｏ：１．５ｉＯｚ等のセラミックス粉末や黒鉛粉
末で形成されており、その厚さはクランクの発生防止の
見地から適宜設定すればよいが、通常０．１〜０．３
ｍｍで十分である。Further, between the outer rotor body 2 and the magnetic shielding cylinder 3, a crank is provided on the side wall of the outer rotor body 2 to relieve the shrinkage of the outer rotor body 2 after molding from being excessively restrained by the cylinder 3. A restraint relaxation layer 4 is interposed to prevent the intrusion of particles. The constraint relaxation N4 is, for example, A
Az O: It is made of ceramic powder or graphite powder such as 1.5 iOz, and its thickness may be set as appropriate from the viewpoint of preventing the occurrence of cranks, but it is usually 0.1 to 0.3
mm is sufficient.
上記複合アウタロータ１を製造するに当り、まず拘束緩
和層４を磁気遮蔽用筒体３の外周面に形成する。形成方
法としては、セラミックス粉末と無機粘結剤（例えば、
水ガラス）°との混合物を前記筒体３のスプレー等によ
り塗布する方法、セラミンク製テープを前記筒体３に巻
き付ける方法等がある。In manufacturing the above composite outer rotor 1, the restraint relaxation layer 4 is first formed on the outer peripheral surface of the magnetic shielding cylinder 3. As for the formation method, ceramic powder and inorganic binder (for example,
There are a method of applying a mixture with water glass) to the cylinder 3 by spraying, a method of wrapping a ceramic tape around the cylinder 3, and the like.
次に、拘束緩和層４が形成された磁気遮蔽用筒体３の回
りに粗加工したアウタロータ本体素材を組み合せてＷＩ
Ｐ （温間乃至熱間等方加圧）やホットプレス等により
、熱間でアウタロータ本体２を磁気遮蔽用筒体３に拘束
緩和層４を介して一体的に成形する。Next, the roughly processed outer rotor main body material is combined around the magnetic shielding cylinder 3 on which the constraint relaxation layer 4 is formed, and the WI
The outer rotor main body 2 is integrally formed with the magnetic shielding cylindrical body 3 via the constraint relaxation layer 4 in a hot manner by P (warm to hot isostatic pressing) or hot pressing.
また、拘束緩和層４が形成された磁気遮蔽用筒体３を内
有した非磁性軽量金属急冷凝固粉末のアウタロータ複合
圧縮成形体を作成し、これをＷＩＰ等により過熱、加圧
状態で粉末の焼結を行うと共に一体成形してもよい。In addition, an outer rotor composite compression molded body of rapidly solidified non-magnetic lightweight metal powder containing a magnetic shielding cylinder 3 in which a restraint relaxation layer 4 is formed is prepared, and this is heated by WIP or the like, and the powder is heated under pressure. It may be sintered and integrally molded.
成形後、成形品を無加圧−状態のまま冷却すれば、アウ
タロータ本体２が磁気遮蔽用筒体３に成形後の冷却に伴
う収縮によってしまり嵌め結合される。After molding, if the molded product is cooled in a non-pressurized state, the outer rotor main body 2 is tightly fitted and coupled to the magnetic shielding cylinder 3 by contraction accompanying cooling after molding.
その後成形製品に適宜精整加工を施し、最終製品とする
。The molded product is then subjected to appropriate refinement processing to produce the final product.
本発明の複合アウタロータ１においては、熱間成形温度
は高温まで自由に設定することができる。In the composite outer rotor 1 of the present invention, the hot forming temperature can be freely set up to a high temperature.
成形後、アウタロータ本体２は冷却により収縮するが、
成形温度からの冷却温度差が大きく、収縮量が大きくて
も、前記筒体３に形成された拘束緩和層４によって、収
縮が前記筒体３によって過大に拘束されず、アウタロー
タ本体２の側壁部にクランクが発生することがないから
である。それ故、アウタロータ本体２の側壁部肉厚を極
めて薄くすることが可能となる。After molding, the outer rotor main body 2 contracts due to cooling.
Even if the cooling temperature difference from the molding temperature is large and the amount of shrinkage is large, the contraction is not excessively restrained by the constraint relaxation layer 4 formed on the cylindrical body 3, and the side wall portion of the outer rotor main body 2 This is because no crank occurs. Therefore, it is possible to make the side wall thickness of the outer rotor main body 2 extremely thin.
また、本発明の複合アウタロータは、成形温度を自由に
選択できることから、拘束緩和層４が形成された磁気遮
蔽用筒体を内有したアウタロータ本体成形型に非磁性軟
質金属溶湯を射出成形し、両者を一体的に成形してもよ
い。In addition, since the composite outer rotor of the present invention can freely select the molding temperature, a non-magnetic soft metal molten metal is injection molded into an outer rotor body mold that includes a magnetic shielding cylinder in which a restraint relaxation layer 4 is formed. Both may be integrally molded.
（発明の効果）
本発明の複合アウタロータは、以上説明した通り、アウ
タロータ本体２を予め製作しておく必要はなく、成形と
同時に磁気遮蔽用筒体３に一体結合することができる。(Effects of the Invention) As explained above, in the composite outer rotor of the present invention, there is no need to manufacture the outer rotor main body 2 in advance, and it can be integrally connected to the magnetic shielding cylinder 3 at the same time as molding.
しかも、アウタロータ本体２側壁部の肉厚に拘らず成形
が容易であって、生産性、経済性に優れる。Furthermore, molding is easy regardless of the wall thickness of the side wall portion of the outer rotor main body 2, resulting in excellent productivity and economical efficiency.
特に、前記筒体３には拘束緩和層４が形成されており、
成形後、冷却に伴うアウタロータ本体２の収縮の拘束に
よって生じる応力が緩和されるので、成形温度を自由に
選択できる。従って、生産性に優れた射出成形手段の適
用が可能となり、またアウタロータ本体２の側壁部肉厚
が極めて薄いものであっても、確実容易に製造すること
ができる利点がある。In particular, a restraint relaxation layer 4 is formed on the cylinder 3,
After molding, the stress caused by the restraint of contraction of the outer rotor main body 2 due to cooling is relaxed, so the molding temperature can be freely selected. Therefore, it is possible to apply injection molding means with excellent productivity, and there is an advantage that even if the side wall of the outer rotor main body 2 is extremely thin, it can be manufactured reliably and easily.
第１図は実施例に係る複合アウタロータの断面図、第２
図はアウタロータ型ＤＣモータの断面説明図、第３図は
従来の複合アウタロータの断面図である。
ｌ・・・複合アウタロータ、２・・・アウタロータ本体
、３・・・磁気遮蔽用筒体、４・・・拘束緩和層。
特 許 出 願 人 久保田鉄工株式会社第１図
第２図
？６FIG. 1 is a sectional view of a composite outer rotor according to an embodiment, and FIG.
The figure is an explanatory cross-sectional view of an outer rotor type DC motor, and FIG. 3 is a cross-sectional view of a conventional composite outer rotor. 1...Composite outer rotor, 2...Outer rotor main body, 3...Magnetic shielding cylinder, 4...Restriction relaxation layer. Patent applicant Kubota Iron Works Co., Ltd. Figure 1 Figure 2? 6
Claims (1)
って、磁気ディスクが装着される円筒状アウタロータ本
体の内周面に磁気遮蔽用筒体が被着された複合アウタロ
ータにおいて、 前記アウタロータ本体は非磁性軽量金属材により熱間成
形されると共に成形後の冷却に伴う収縮によって前記筒
体にしまり嵌め結合しており、前記筒体とアウタロータ
本体との間にアウタロータ本体の収縮が前記筒体によっ
て過度に拘束されるのを緩和するための拘束緩和層が介
装されていることを特徴とする磁気ディスク装着用複合
アウタロータ。(1) An outer rotor of a magnetic disk rotation drive motor, which is a composite outer rotor in which a magnetic shielding cylinder is adhered to the inner peripheral surface of a cylindrical outer rotor body to which a magnetic disk is attached, wherein the outer rotor body is non-magnetic and lightweight. The outer rotor body is hot-formed from a metal material and tightly fitted into the cylindrical body due to shrinkage due to cooling after molding, and the shrinkage of the outer rotor body is excessively restrained by the cylindrical body between the cylindrical body and the outer rotor body. What is claimed is: 1. A composite outer rotor for mounting a magnetic disk, characterized in that a restraint relaxation layer is interposed therein to relieve the stress caused by the magnetic disk.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63020289A JPH01198261A (en) | 1988-01-29 | 1988-01-29 | Composite outer rotor for loading magnetic disk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63020289A JPH01198261A (en) | 1988-01-29 | 1988-01-29 | Composite outer rotor for loading magnetic disk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01198261A true JPH01198261A (en) | 1989-08-09 |
Family
ID=12023010
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63020289A Pending JPH01198261A (en) | 1988-01-29 | 1988-01-29 | Composite outer rotor for loading magnetic disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01198261A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0854558A2 (en) * | 1997-01-21 | 1998-07-22 | Isuzu Ceramics Research Institute Co., Ltd. | Structure of a rotor for generators and method of manufacturing the same rotor |
-
1988
- 1988-01-29 JP JP63020289A patent/JPH01198261A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0854558A2 (en) * | 1997-01-21 | 1998-07-22 | Isuzu Ceramics Research Institute Co., Ltd. | Structure of a rotor for generators and method of manufacturing the same rotor |
| EP0854558A3 (en) * | 1997-01-21 | 2000-07-12 | Isuzu Ceramics Research Institute Co., Ltd. | Structure of a rotor for generators and method of manufacturing the same rotor |
| US6144130A (en) * | 1997-01-21 | 2000-11-07 | Isuzu Ceramics Research Institute Co., Ltd. | Structure of rotor for generators and method of manufacturing the same rotor |
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