JPH01320602A - Magneto-optical disk erazing device - Google Patents
Magneto-optical disk erazing deviceInfo
- Publication number
- JPH01320602A JPH01320602A JP15416188A JP15416188A JPH01320602A JP H01320602 A JPH01320602 A JP H01320602A JP 15416188 A JP15416188 A JP 15416188A JP 15416188 A JP15416188 A JP 15416188A JP H01320602 A JPH01320602 A JP H01320602A
- Authority
- JP
- Japan
- Prior art keywords
- magneto
- optical disk
- magnet
- magnetic flux
- iron
- 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
- 230000004907 flux Effects 0.000 claims abstract description 10
- 229910052796 boron Inorganic materials 0.000 claims abstract description 7
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 abstract description 5
- 238000005266 casting Methods 0.000 abstract description 2
- 238000005096 rolling process Methods 0.000 abstract description 2
- NPPQSCRMBWNHMW-UHFFFAOYSA-N Meprobamate Chemical compound NC(=O)OCC(C)(CCC)COC(N)=O NPPQSCRMBWNHMW-UHFFFAOYSA-N 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000010365 information processing Effects 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- KZUNJOHGWZRPMI-UHFFFAOYSA-N samarium atom Chemical compound [Sm] KZUNJOHGWZRPMI-UHFFFAOYSA-N 0.000 description 1
- 229910000938 samarium–cobalt magnet Inorganic materials 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は情報の記録、再生に用いられる書換え可能型光
磁気ディスクの消去装置に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an erasing device for a rewritable magneto-optical disk used for recording and reproducing information.
(従来の技術)
従来、書換え可能型光磁気ディスクはそのディスクに記
録された全情報が不用になった場合、書き込み時と同様
にレーザー光で局部的に加熱しつつ1方向磁界をかけな
からを全トラックを走査して消去を行なっていた。(Prior art) Conventionally, when all of the information recorded on a rewritable magneto-optical disk is no longer needed, a rewritable magneto-optical disk is heated locally with a laser beam and no unidirectional magnetic field is applied, just as when writing. All tracks were scanned and erased.
(発明が解決しようとする課題)
しかし、従来の書換え可能型光磁気ディスクの消去方法
では、全トラックを走査する必要があるため、例えばデ
ィスク回転数90Orpm、トラックピッチ1.6μm
、全記録領域幅30mmの光磁気ディスク装置の場合、
消去に要する時間は20分以上におよび、高速性が要求
される情報処理分野においては大きな問題点となってい
た。(Problem to be Solved by the Invention) However, in the conventional erasing method for a rewritable magneto-optical disk, it is necessary to scan all tracks.
, in the case of a magneto-optical disk device with a total recording area width of 30 mm,
The time required for erasing is 20 minutes or more, which has been a major problem in the field of information processing where high speed is required.
また、従来の消去方法において全情報を消去した光磁気
ディスクに再度新情報の記録を行なう場合、記録情報の
誤り率が非常に大きくなるという情報記録媒体として致
命的とも言える欠点があった。これは磁化方向の反転が
レーザー光の走査した部分にしか起こらないため、書き
込み時と消去時におけるレーザー光の走査位置のズレに
よって消去が完全に行なわれない為である。Furthermore, when new information is recorded again on a magneto-optical disk from which all information has been erased using the conventional erasing method, the error rate of the recorded information becomes extremely high, which is a fatal drawback for an information recording medium. This is because the reversal of the magnetization direction occurs only in the area scanned by the laser beam, and erasing cannot be completed completely due to a shift in the scanning position of the laser beam during writing and erasing.
(課題を解決するための手段)
上記課題を解決するために本発明の光磁気ディスクの消
去装置は、1方向に着磁されたR−鉄一・ぢロン系磁石
(ただしRはYを含む希土類元素のうち少なくとも1種
)と、先端部において前記磁石の断面積の1/2以下の
断面積に磁束を集束するポールピースを有することを特
徴とする。(Means for Solving the Problems) In order to solve the above problems, the magneto-optical disk erasing device of the present invention uses an R-iron diron magnet magnetized in one direction (where R includes Y). at least one rare earth element) and a pole piece that focuses magnetic flux on a cross-sectional area of 1/2 or less of the cross-sectional area of the magnet at the tip.
(実施例) 本発明の一実施例を図面に基づいて説明する。(Example) An embodiment of the present invention will be described based on the drawings.
第1図において1はR−鉄−ボロン系磁石で、2はポー
ルピースで先端部では磁石1の断面積の1/3に磁束を
集束している。2個のポールピース間には光磁気ディス
ク4が収納されているジャケット5より広い空隙がある
ため、磁気回路を閉じるためのヨーク3に設けられた案
内溝にジャケット5の突起部が案内された状態でジャケ
ット5を通過させることができる。In FIG. 1, 1 is an R-iron-boron magnet, and 2 is a pole piece whose tip focuses magnetic flux on 1/3 of the cross-sectional area of the magnet 1. Since there is a gap between the two pole pieces that is wider than the jacket 5 in which the magneto-optical disk 4 is housed, the protrusion of the jacket 5 is guided to the guide groove provided in the yoke 3 for closing the magnetic circuit. The jacket 5 can be passed through in this state.
本実施例の磁石は特公昭62−276803に記載され
る製造方法によった。すなわちその組成がN d +s
F e 77B 8である合金を銹導炉で溶解し、鋳型
に鋳造する。次に磁石に異方性を付与するために圧延加
工し板状磁石を得た。本実施例の光磁気ディスク消去装
置の空隙部における磁束密度は、15000ガウスであ
り、光磁気ディスクの記録膜の常温時の保磁力は800
0ガウス程度であるから光磁気ディスクをジャケットに
入れたままの状態で空隙部を通過させることによって内
部の光磁気ディスクには書き込まれた情報の消去に充分
な磁界をかけることができる。フェライト磁石の残留磁
束密度は、おおむね3.5KOeであるから、本実施例
と同一構造で光磁気ディスク消去装置を構成した場合空
隙部で15000ガウスを得るためには非常に断面積の
大きい磁石が必要になり現実的には装置の構成が非常に
困難で使用しにくいものとなってしまう。またサマーリ
ウムコバルト系磁石を用いた場合においてはサマリウム
が高価であることから同一性能を得るためには本発明の
2倍から3倍のコストがかかつてしまう。一方、鋳造、
圧延を主工程としたR−鉄−ボロン系1磁石は原料コス
トと製造コストの両者を低く抑えたまま、高い残留磁束
密度を持つ磁石の提供することが可能となっている。The magnet of this example was manufactured by the method described in Japanese Patent Publication No. 62-276803. That is, its composition is N d +s
The alloy, F e 77B 8, is melted in a melting furnace and cast into molds. Next, in order to impart anisotropy to the magnet, it was rolled to obtain a plate-shaped magnet. The magnetic flux density in the gap of the magneto-optical disk erasing device of this embodiment is 15,000 Gauss, and the coercive force of the recording film of the magneto-optical disk at room temperature is 800 Gauss.
Since the magnetic field is about 0 Gauss, by passing the magneto-optical disk inside the jacket through the gap, a magnetic field sufficient to erase written information can be applied to the magneto-optical disk inside. The residual magnetic flux density of a ferrite magnet is approximately 3.5 KOe, so if a magneto-optical disk erasing device is configured with the same structure as this example, a magnet with a very large cross-sectional area will be required to obtain 15,000 Gauss in the gap. In reality, this would make the configuration of the device extremely difficult and difficult to use. Furthermore, in the case of using a samarium cobalt magnet, since samarium is expensive, the cost will be two to three times higher than that of the present invention in order to obtain the same performance. On the other hand, casting
The R-iron-boron type 1 magnet, whose main process is rolling, makes it possible to provide a magnet with a high residual magnetic flux density while keeping both raw material cost and manufacturing cost low.
(発明の効果)
本発明は、以上説明したように、光磁気ディスク消去装
置において、1方向に着磁されたR−鉄−ボロン系磁石
と、先端部において前記磁石の断面積の1/2以下の断
面積に磁束を集束するポールピースを有することによっ
て小型でかつ低コストでありながら短時間で光磁気ディ
スクの前記録情報の消去かできる。また装置に光磁気デ
ィスクの回転手段を付与することによって磁石の使用量
をほぼ1/3にすることも可能とした。(Effects of the Invention) As described above, the present invention provides a magneto-optical disk erasing device that includes an R-iron-boron magnet magnetized in one direction, and a tip portion that is 1/2 of the cross-sectional area of the magnet. By having a pole piece that focuses magnetic flux on the following cross-sectional area, the previously recorded information on the magneto-optical disk can be erased in a short time while being small and at low cost. Furthermore, by providing the device with a means for rotating the magneto-optical disk, it has become possible to reduce the amount of magnets used by approximately one-third.
第1図は本発明にかかる光磁気ディスク消去装置の断面
斜視図、第2図は本発明にかかる光磁気ディスク消去装
置の正面図である。
1・・・磁石
2・・・ポールピース
3・・・ヨーク
4・・・光磁気ディスク
5・・・ジャケット
以上
出願人 セイコーエプソン株式会社
代理人弁理士 上柳雅誉 他1名FIG. 1 is a sectional perspective view of a magneto-optical disk erasing device according to the present invention, and FIG. 2 is a front view of the magneto-optical disk erasing device according to the present invention. 1... Magnet 2... Pole piece 3... Yoke 4... Magneto-optical disk 5... Jacket and above Applicant Seiko Epson Corporation Representative Patent Attorney Masayoshi Kamiyanagi and 1 other person
Claims (1)
しRはYを含む希土類元素のうち少なくとも1種)と、
先端部において前記磁石の断面積の1/2以下の断面積
に磁束を集束するポールピースを有することを特徴とす
る光磁気ディスク消去装置。(1) R-iron-boron magnet magnetized in one direction (where R is at least one rare earth element including Y);
A magneto-optical disk erasing device comprising a pole piece that focuses magnetic flux on a cross-sectional area of 1/2 or less of the cross-sectional area of the magnet at its tip.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15416188A JPH01320602A (en) | 1988-06-22 | 1988-06-22 | Magneto-optical disk erazing device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15416188A JPH01320602A (en) | 1988-06-22 | 1988-06-22 | Magneto-optical disk erazing device |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH01320602A true JPH01320602A (en) | 1989-12-26 |
Family
ID=15578166
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP15416188A Pending JPH01320602A (en) | 1988-06-22 | 1988-06-22 | Magneto-optical disk erazing device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH01320602A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1484748A1 (en) * | 2002-03-14 | 2004-12-08 | Orient Instrument Computer Co., Ltd | Recorded data deleting device for hard disk |
-
1988
- 1988-06-22 JP JP15416188A patent/JPH01320602A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1484748A1 (en) * | 2002-03-14 | 2004-12-08 | Orient Instrument Computer Co., Ltd | Recorded data deleting device for hard disk |
EP1484748A4 (en) * | 2002-03-14 | 2005-12-14 | Orient Instr Comp Co Ltd | Recorded data deleting device for hard disk |
US7265925B2 (en) | 2002-03-14 | 2007-09-04 | Orient Instrument Computer Co. Ltd. | Recorded data deleting device for hard disk |
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