JPH0334104A - Auxiliary magnetic field applying device - Google Patents
Auxiliary magnetic field applying deviceInfo
- Publication number
- JPH0334104A JPH0334104A JP16683289A JP16683289A JPH0334104A JP H0334104 A JPH0334104 A JP H0334104A JP 16683289 A JP16683289 A JP 16683289A JP 16683289 A JP16683289 A JP 16683289A JP H0334104 A JPH0334104 A JP H0334104A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- magnetic
- coil
- plate
- auxiliary
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 178
- 230000004907 flux Effects 0.000 claims abstract description 39
- 239000003302 ferromagnetic material Substances 0.000 claims description 6
- 230000017525 heat dissipation Effects 0.000 claims description 2
- 230000003287 optical effect Effects 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- 238000004804 winding Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
［産業上の利用分野］
本発明は光ビームと連係して補助磁界を与え、光磁気記
録媒体上へ情報を記録或は記録された情報を消去する補
助磁界印加装置に関し、特に電磁石を用いる補助磁界印
加装置のヨーク部の形態に特徴を有する補助磁界印加装
置に関するものである。
［従来の技術］
従来、消去可能な光デイスク装置の一種である光磁気方
式では、磁性膜をレーザスポットで過熱し、ここへ数百
エルステッドの磁界を加え、過熱を取り除いた際に磁性
膜が外部磁界の方向に磁化されるという原理を用いて記
録及び消去を行っている。つまり、磁化の所定の方向が
記録とすれば、その反対方向は消去となる。
第４図は上記光磁気方式を実施するための従来の外部磁
界発生装置の第１の構成例を示す図である。同図におい
て、外部磁界発生装置３０は、記録用光磁気ディスク４
１上に配置される永久磁石４２と、ここでは図示されて
いないが永久磁石４２の長手方向（ディスクｌに対して
垂直方向）の軸４３を中心として永久磁石４２を回転さ
せるアクチュエータ（例えば、マグネット等を用いた構
成）とを具備している。永久磁石４２はディスク４１の
半径方向に延びる棒状に形成され、巾方向にＮ、Ｓと磁
化されている。この磁石の磁界のディスクに垂直な成分
が、ディスク４１の磁性膜の磁極反転に寄与する。即ち
、図示するようにディスク４１に対して垂直方向に磁極
Ｓ、Ｎを配列した永久磁石２をアクチュエータによって
、軸４３を中心に１８０°回転させることにより磁界の
向きを選択して磁気記録または消去が行われる。
第５図は従来の外部磁界発生装置の第２の構成例を示す
図である。この外部磁界発生装置３２は、同図に示すよ
うに、主として電磁石４４から構成されるものである。
電磁石４４は細長い形状をしており、記録用光磁気ディ
スク４１の半径方向に配置されている。電磁石４４の下
端部には突起状の歯４５，４６ａ、４６ｂが形成されて
いる。中央の歯４５には、コイル４７が巻かれており、
このコイル４７に電流を流すことにより磁界を発生させ
る。発生した磁界は、中央の歯４５の先端から両側の歯
４６ａ、４６ｂへと入り、この磁界のディスク４１に垂
直な成分が外部磁界となって磁性膜経の記録または消去
を行う。この構成の場合は、磁界の反転は電画の流す方
向を反転させることにより行なわれるので、磁界の反転
速度が早い利点がある。
［発明が解決しようとしている課題］
しかしながら、上記従来の第１及び第２の外部磁界発生
装置では、それぞれ次のような問題点があった。
第１の構成例による外部磁界発生装置においては、磁界
の極性を反転させるためには、何らかの外部の力、即ち
、アクチュエータにより永久磁石４２を機械的に回転さ
せなければならず、大きな慣性のある磁石を回転させる
ための動作時間は約十〜数百（ｍｓｅｃ）を要し、高速
駆動が難しく、そのため使用上、種々の制限があった。
また、第２の構成では、ディスク４１に必要とする磁界
強度を与えるために第５図のコイル４７を必要回数巻く
ときに、歯４５が長いため、銅損を考慮して高さ方向（
ディスク４１の垂直方向）に巻きあげるしかなく、外部
磁界発生装置全体が大きくなるという欠点があった。そ
してこの欠点が、光磁気ディスク装置の小型化、薄型化
に障害をもたらしていた。
また、従来コイルの銅損により発生した熱を放出させる
ための放熱板は通常、外部磁界発生装置高さ方向に設け
られ、これも装置の小型化を妨げる要因となっていた。[Industrial Application Field] The present invention relates to an auxiliary magnetic field application device that applies an auxiliary magnetic field in conjunction with a light beam to record information on a magneto-optical recording medium or erase recorded information, and particularly relates to an auxiliary magnetic field application device that applies an auxiliary magnetic field in conjunction with a light beam, and records information on a magneto-optical recording medium or erases recorded information. The present invention relates to an auxiliary magnetic field applying device characterized by the shape of a yoke portion of the magnetic field applying device. [Prior Art] Conventionally, in the magneto-optical method, which is a type of erasable optical disk device, a magnetic film is heated with a laser spot, a magnetic field of several hundred oersted is applied thereto, and when the overheating is removed, the magnetic film changes. Recording and erasing is performed using the principle that magnetization occurs in the direction of an external magnetic field. That is, if a predetermined direction of magnetization is used for recording, the opposite direction is used for erasing. FIG. 4 is a diagram showing a first configuration example of a conventional external magnetic field generating device for implementing the above magneto-optical method. In the same figure, the external magnetic field generator 30 is connected to a recording magneto-optical disk 4.
1 and an actuator (for example, a magnet etc.). The permanent magnet 42 is formed into a bar shape extending in the radial direction of the disk 41, and is magnetized in N and S directions in the width direction. The component of the magnetic field of this magnet perpendicular to the disk contributes to the magnetic pole reversal of the magnetic film of the disk 41. That is, as shown in the figure, the direction of the magnetic field is selected by rotating the permanent magnet 2, which has magnetic poles S and N arranged perpendicularly to the disk 41, by 180 degrees around the shaft 43 using an actuator, thereby performing magnetic recording or erasing. will be held. FIG. 5 is a diagram showing a second configuration example of a conventional external magnetic field generator. As shown in the figure, this external magnetic field generator 32 is mainly composed of an electromagnet 44. The electromagnet 44 has an elongated shape and is arranged in the radial direction of the magneto-optical recording disk 41. Protruding teeth 45, 46a, and 46b are formed at the lower end of the electromagnet 44. A coil 47 is wound around the central tooth 45.
A magnetic field is generated by passing a current through this coil 47. The generated magnetic field enters the teeth 46a and 46b on both sides from the tip of the central tooth 45, and the component of this magnetic field perpendicular to the disk 41 becomes an external magnetic field to record or erase the magnetic film length. In this configuration, since the magnetic field is reversed by reversing the direction in which the electric picture flows, there is an advantage that the magnetic field can be reversed quickly. [Problems to be Solved by the Invention] However, the first and second conventional external magnetic field generating devices described above each have the following problems. In the external magnetic field generating device according to the first configuration example, in order to reverse the polarity of the magnetic field, the permanent magnet 42 must be mechanically rotated by some external force, that is, an actuator, and a large inertia is required. The operation time required to rotate the magnet is about ten to several hundred milliseconds (msec), making it difficult to drive at high speed, and as a result, there are various limitations in use. In addition, in the second configuration, when winding the coil 47 shown in FIG. 5 the necessary number of times in order to provide the required magnetic field strength to the disk 41, since the teeth 45 are long, the height direction (
The only way to do this is to wind the magnetic field in the perpendicular direction of the disk 41, which has the disadvantage that the entire external magnetic field generator becomes large. This drawback poses an obstacle to miniaturization and thinning of magneto-optical disk devices. Further, conventionally, a heat sink for dissipating heat generated by copper loss in the coil is usually provided in the height direction of the external magnetic field generator, and this has also been a factor preventing miniaturization of the device.
本発明の目的は、磁界の印加が効率的に行え、かつ薄型
の光磁気ディスク装置とすることができる補助磁界印加
装置を提供することにある。
本発明の目的は、磁極及びコイルの磁性板への取付け、
組立が容易である補助磁界印加装置を提供することにあ
る。
以上のような目的の達成のため、第１図〜第３図に示す
ように本発明の請求項１記載の補助磁界印加装置は、情
報記録媒体６の記録領域の巾方向に延在され、記録領域
に対向される磁界放出面１ａを備えた強磁性体で作られ
た磁心部ｌと、この磁心部（１ｂ〉に扁平状に巻回され
たコイル３と、
強磁性体で作られ、前記磁界放出面１ａと磁気的に連結
されれたヨーク部とを有し、
前記ヨーク部が下記イ）、口）の特徴を有する磁束帰還
プレート４と前記磁心部ｌと前記コイル３を覆う磁性板
２とから構成されることを特徴とする特
イ）前記磁界放出面１ａに磁気的に対応し、且つ近接し
て配された磁束帰還部４ａを有すること口）当該補助磁
界印加装置の保持部材及びコイルで発生する熱の放熱板
として機能することまた、請求項２記載の補助磁界印加
装置は前記磁束帰還プレート４と磁性板２とが、所定時
に分離される構成であることを特徴としている。
また、請求項３記載の補助磁界印加装置は前記磁心部１
が前記磁界放出面１ａと前記コイル３を巻く部分ｔｂか
ら構成され、全体が丁字形であることを特徴とする
［作用］
上記補助磁界印加装置によれば、以下のような作用を有
する。
磁心部１の磁界放出面１ａから放出された磁界は、ヨー
ク部として機能し、かつ補助磁界印加装置の支持板とし
て機能する１ｉｆ１束帰還プレート４の磁束帰還部４ａ
に吸収され、前記磁界放出面１ａと磁束帰還部４ａの近
傍に配置される記録媒体に対して、効率良く且つ均一な
磁界を印加させる。
また、コイル３で発生した熱は、薄く作られた磁性板２
及び同じく薄く作られた磁束帰還プレート４全体におよ
び、無理なく放熱される。
また、請求項３記載の補助磁界印加装置においては、通
電時にコイルを巻く部分１ｂに発生した磁界は磁界放出
面１ａからディスク半径方向において略均等に放出され
る。
［実施例］
以下、本発明の補助磁界印加装置について具体的な実施
例に基づき詳細に説明する。
第１図は本発明の補助磁界印加装置を示す分解立体図で
ある。同図において、２は強磁性体からなる磁性板であ
り、磁心部とコイルを覆う凸状部２ａを有し、該凸状部
２ａを保持する保持部２ｂを有している。該保持部２ｂ
には、後述する磁束帰還プレートへの取付は用穴２ｃが
設けられている。
１は磁極として機能する磁心部であり、磁心部１、扁平
状に旋回されたコイル３が巻きつけられている。磁心部
１は本実施例においては、丁字形であり、Ｔの一部が磁
界印加用の磁界放出面１ａとなっている。該磁界放出面
１ａは記録媒体の記録領域延在方向に延びる面となって
おり、記録媒体がディスク状ならば、半径方向に棒状に
配置される。磁心部ｌはまた、磁界放出面１ａに直交す
るＴの１部に相当する部分１ｂを有しており、該部分１
ｂを中心としてコイル３が扁平状に巻かれている。
４は同じく強磁性体で作られた磁束帰還プレートであり
、記録媒体の記録領域面に平行な薄い板状に作られ、大
面積を有している。該磁束帰還プレート４には記録媒体
６の配置方向にＬ状に折れ曲がった２つの磁束帰還部４
ａを有しており、その磁束帰還部４ａの間は開口とされ
、前記磁界放出面１ａが中心に対向した状態で配置され
る。また磁束帰還プレート４には前記取付は用穴２ｃと
対応する取付は用穴４ｂが設けられている。また、開口
と反対側の端部には、磁束帰還プレート４を光デイスク
装置本体の所定部に回動自在に支持する不図示の軸を通
す支持穴４ｃが設けられている。
通電により磁心部１の磁界放出面１ａにより放出される
磁界は磁束帰還部４ａの存在によりより効率的に記録媒
体に向けられる。この様子を第３図ｆａ） 、 （ｂ）
、 （ｃ）に示す。（ａ） 、 （ｂ） 、 （ｃ）
はそれぞれ磁束帰還部４ａのＬ状の折れ曲がりの大きさ
によって、磁力線がどのように変化するかを示した図で
ある。第３図（ｃ）は磁束帰還部４ａが形成されていな
い場合の図である。折れ曲がり長さβの一番大きな第３
図（ａ）が最も安定した磁界を記録媒体方向に形成する
ことが分かる。
また、第１図に示すように電磁石の高さをきわめて低く
しようとした場合、磁束帰還プレート４自体を支持体と
することにより、装置の高さ方向に新たなる取付は部材
を付加することなく支持が可能となる。また、通常なら
、コイルを扁平に巻回することによる銅損で発生する熱
を放熱する放熱板を取り付けなければならないのに対し
、本構成では、磁束帰還プレート４自体が広いので、放
熱効果が大きくなり、温度上昇による銅損が抑えらえる
。また、前記磁束帰還プレート４と磁性板２とが分離す
る構成であるため、磁心部ｌ及びコイル３の磁性板２へ
の取付け、組立が容易になる。さらに磁束帰還部４ａへ
の取付けが装置の巾方向の移動で行えるため、薄型の光
磁気記録装置の実現が可能となる利点が生じる。
なお、第１図及び第２図において、６は記録媒体として
の光磁気ディスク、５はカートリッジ、５ａはカートリ
ッジ窓である。
【他の実施例Ｊ
本発明は前記実施例に限らず種々の変形、応用が可能で
ある。・
第１図実施例では、磁性板２の磁束帰還プレート４への
取付けは、ネジにより行われるが、平板間のスポット溶
接により行ってもよい。これは、磁性板２と磁束帰還プ
レート４の分離が可能である構成は主に巻線不良、断線
等の際に交換が可能であり、また、コアの取付は位置調
整も可能にできることに関係するからである。
また、第１図実施例では、磁束帰還プレート４はディス
クの脱着に対して、ディスク挿入方向に直交する不図示
の支軸で回動可能である構成を示しているが、これ以外
にもスライドさせる構成等の各種の構成を取ることが可
能である。
また、磁心部ｌの磁界放出面１ａの数は単数に限られず
、複数であってもよく、磁束帰還プレート４の磁束帰還
部４ａの形状、数、構成も第１１１の実施例に限定され
るものではない。
また、前述の記載においては、光磁気記録装置に適用す
る補助磁界印加装置について説明したが、本発明の特徴
がコンパクトで薄型な構成で効率よく磁界を印加すると
いう点にある以上、本発明は上記光磁気記録装置以外の
磁界印加装置としても適用することができるのは明らか
である。
［発明の効果］
以上、詳細に説明したように、本発明の補助磁界印加装
置によれば、以下のような効果を有する。
請求項１記載の補助磁界印加装置によれば、補助磁界印
加装置の支持板を磁束帰還プレート４とし、さらに前記
磁界放出面に近接して配された磁束帰還部４ａを設ける
ことにより磁界が効率的に記録媒体に印加される効果を
有する。
また、磁束帰還プレート４自体が当該補助磁界印加装置
の保持部材及びコイルで発生する熱の放熱板として機能
することにより、新たなる保持部材及び放熱板（一般的
にこれらは光磁気記録装置の高さ方向に設けられること
が多い）を設ける必要がなくなり、薄型の光磁気記録装
置を提供できる。
また、請求項２記載の補助磁界印加装置によれば、磁心
部ｌとコイル３の取付け、組立が容易に行うことができ
る効果がある。
また、請求項３記載の補助磁界印加装置によれば、磁心
部１が磁界放出面と前記コイルを巻く部分から構成され
、全体が丁字形で長方形状の磁心部にコイルを巻く構成
なので、体積を少なくでき装置の薄型化に寄与し、且つ
銅損を少なくできることにより、前記磁束帰還プレート
４自体が放熱板として機能する効果を助けることができ
る。An object of the present invention is to provide an auxiliary magnetic field applying device that can efficiently apply a magnetic field and can provide a thin magneto-optical disk device. The object of the present invention is to attach a magnetic pole and a coil to a magnetic plate,
An object of the present invention is to provide an auxiliary magnetic field applying device that is easy to assemble. To achieve the above object, as shown in FIGS. 1 to 3, the auxiliary magnetic field applying device according to claim 1 of the present invention extends in the width direction of the recording area of the information recording medium 6, A magnetic core part l made of a ferromagnetic material and having a magnetic field emitting surface 1a facing the recording area, a coil 3 wound in a flat shape around this magnetic core part (1b), and a coil 3 made of a ferromagnetic material, It has a yoke part magnetically connected to the magnetic field emitting surface 1a, and the yoke part has a magnetic flux return plate 4 having the following characteristics (a) and (a), a magnetic core part l, and a magnetic material covering the coil 3. A) A magnetic flux return portion 4a that magnetically corresponds to the magnetic field emitting surface 1a and is disposed close to the plate 2. A) Holding of the auxiliary magnetic field applying device. Further, the auxiliary magnetic field applying device according to claim 2 is characterized in that the magnetic flux return plate 4 and the magnetic plate 2 are separated at a predetermined time. There is. Further, the auxiliary magnetic field applying device according to claim 3 is characterized in that the magnetic core portion 1
is composed of the magnetic field emitting surface 1a and the portion tb around which the coil 3 is wound, and is characterized in that the whole has a T-shape. [Function] The auxiliary magnetic field application device has the following effects. The magnetic field emitted from the magnetic field emitting surface 1a of the magnetic core portion 1 is transmitted to the magnetic flux return portion 4a of the 1if1 flux return plate 4, which functions as a yoke portion and also serves as a support plate of the auxiliary magnetic field application device.
A uniform magnetic field is efficiently applied to the recording medium disposed near the magnetic field emitting surface 1a and the magnetic flux return section 4a. In addition, the heat generated by the coil 3 is transferred to the thin magnetic plate 2.
The heat is radiated easily throughout the magnetic flux return plate 4, which is also made thin. Further, in the auxiliary magnetic field applying device according to the third aspect, the magnetic field generated in the coiled portion 1b when energized is emitted substantially uniformly in the disk radial direction from the magnetic field emitting surface 1a. [Examples] Hereinafter, the auxiliary magnetic field applying device of the present invention will be described in detail based on specific examples. FIG. 1 is an exploded three-dimensional view showing the auxiliary magnetic field applying device of the present invention. In the figure, reference numeral 2 denotes a magnetic plate made of ferromagnetic material, which has a convex portion 2a that covers the magnetic core and the coil, and a holding portion 2b that holds the convex portion 2a. The holding part 2b
A hole 2c is provided for attachment to a magnetic flux return plate, which will be described later. Reference numeral 1 denotes a magnetic core portion that functions as a magnetic pole, around which the magnetic core portion 1 and a flattened coil 3 are wound. In this embodiment, the magnetic core portion 1 is T-shaped, and a portion of the T serves as a magnetic field emitting surface 1a for applying a magnetic field. The magnetic field emitting surface 1a is a surface extending in the direction in which the recording area of the recording medium extends, and if the recording medium is disk-shaped, it is arranged like a bar in the radial direction. The magnetic core part l also has a part 1b corresponding to a part of T perpendicular to the magnetic field emission surface 1a, and the part 1
The coil 3 is wound in a flat shape around b. A magnetic flux return plate 4 is also made of ferromagnetic material, is made in the shape of a thin plate parallel to the recording area surface of the recording medium, and has a large area. The magnetic flux return plate 4 has two magnetic flux return portions 4 bent in an L shape in the direction in which the recording medium 6 is arranged.
a, an opening is formed between the magnetic flux return portions 4a, and the magnetic field emitting surface 1a is arranged facing the center. Further, the magnetic flux return plate 4 is provided with a mounting hole 4b corresponding to the mounting hole 2c. Further, at the end opposite to the opening, a support hole 4c is provided through which a shaft (not shown) that rotatably supports the magnetic flux return plate 4 at a predetermined portion of the optical disk device main body is passed. The magnetic field emitted by the magnetic field emitting surface 1a of the magnetic core portion 1 when energized is directed toward the recording medium more efficiently due to the presence of the magnetic flux return portion 4a. This situation is shown in Figure 3 fa) and (b).
, shown in (c). (a), (b), (c)
These are diagrams each showing how the lines of magnetic force change depending on the size of the L-shaped bend of the magnetic flux return section 4a. FIG. 3(c) is a diagram when the magnetic flux return portion 4a is not formed. The third with the largest bending length β
It can be seen that the most stable magnetic field is formed in the direction of the recording medium in Figure (a). Furthermore, when trying to make the height of the electromagnet extremely low as shown in Figure 1, by using the magnetic flux return plate 4 itself as a support, new installation in the height direction of the device can be done without adding any additional members. support is possible. In addition, normally, a heat sink must be attached to dissipate heat generated by copper loss due to flat winding of the coil, but in this configuration, the magnetic flux return plate 4 itself is wide, so the heat dissipation effect is reduced. copper loss due to temperature rise can be suppressed. Further, since the magnetic flux return plate 4 and the magnetic plate 2 are configured to be separated, attachment and assembly of the magnetic core portion l and the coil 3 to the magnetic plate 2 is facilitated. Furthermore, since attachment to the magnetic flux return section 4a can be performed by moving the device in the width direction, there is an advantage that a thin magneto-optical recording device can be realized. In FIGS. 1 and 2, 6 is a magneto-optical disk as a recording medium, 5 is a cartridge, and 5a is a cartridge window. [Other Embodiments J The present invention is not limited to the embodiments described above, and various modifications and applications are possible. - In the embodiment shown in FIG. 1, the magnetic plate 2 is attached to the magnetic flux return plate 4 using screws, but it may also be done by spot welding between the flat plates. This is because the configuration in which the magnetic plate 2 and the magnetic flux return plate 4 can be separated allows replacement mainly in the event of a winding failure or wire breakage, and the core installation also allows for position adjustment. Because it does. In addition, in the embodiment shown in FIG. 1, the magnetic flux return plate 4 is configured to be rotatable on a support shaft (not shown) that is orthogonal to the disk insertion direction in order to attach and detach the disk. It is possible to take various configurations such as a configuration in which the Further, the number of magnetic field emitting surfaces 1a of the magnetic core portion l is not limited to one, but may be plural, and the shape, number, and configuration of the magnetic flux return portions 4a of the magnetic flux return plate 4 are also limited to the 111th embodiment. It's not a thing. Further, in the above description, an auxiliary magnetic field applying device applied to a magneto-optical recording device has been described, but since the feature of the present invention is that it efficiently applies a magnetic field with a compact and thin structure, the present invention It is obvious that the present invention can also be applied as a magnetic field application device other than the above-mentioned magneto-optical recording device. [Effects of the Invention] As described above in detail, the auxiliary magnetic field applying device of the present invention has the following effects. According to the auxiliary magnetic field application device according to claim 1, the magnetic flux return plate 4 is used as the support plate of the auxiliary magnetic field application device, and the magnetic flux return portion 4a is provided close to the magnetic field emission surface, so that the magnetic field can be efficiently applied. It has the effect of being applied to the recording medium. In addition, the magnetic flux return plate 4 itself functions as a heat sink for the heat generated by the holding member and coil of the auxiliary magnetic field applying device, thereby creating a new holding member and heat sink (generally, these are This eliminates the need to provide a magneto-optical recording device (which is often provided in the horizontal direction), making it possible to provide a thin magneto-optical recording device. Further, according to the auxiliary magnetic field applying device according to the second aspect, there is an effect that the attachment and assembly of the magnetic core portion l and the coil 3 can be easily performed. Further, according to the auxiliary magnetic field applying device according to claim 3, the magnetic core portion 1 is composed of a magnetic field emitting surface and a portion around which the coil is wound, and the coil is wound around the rectangular magnetic core portion having a T-shape as a whole. This contributes to making the device thinner and reduces copper loss, which helps the magnetic flux return plate 4 itself function as a heat sink.
第１図は本発明の補助磁界印加装置を示す分解立体図で
ある。
第２図は本発明の補助磁界印加装置の断面図である。
第３図は（ａ） 、 （ｂ） 、 （ｃ）それぞれ磁心
部１の磁界放出面１ａにより放出される磁界が磁束帰還
部４ａの長さによりどのように変化するかを示す図であ
る。
第４図及び第５図は従来の補助磁界印加装置の概略構成
図である。
１：磁心部、１ａ：磁界放出面、１ｂ＝コイルを巻く部
分、２：Ｍｉ性板、３：コイル、４：磁束帰還プレート
、４ａ：磁束帰還部FIG. 1 is an exploded three-dimensional view showing the auxiliary magnetic field applying device of the present invention. FIG. 2 is a sectional view of the auxiliary magnetic field applying device of the present invention. FIGS. 3A, 3B, and 3C are diagrams each showing how the magnetic field emitted by the magnetic field emitting surface 1a of the magnetic core portion 1 changes depending on the length of the magnetic flux return portion 4a. 4 and 5 are schematic configuration diagrams of a conventional auxiliary magnetic field applying device. 1: Magnetic core part, 1a: Magnetic field emission surface, 1b = Coil winding part, 2: Mi plate, 3: Coil, 4: Magnetic flux return plate, 4a: Magnetic flux return part
Claims (1)
媒体上へ情報を記録或は記録された情報を消去する補助
磁界印加装置において、 情報記録媒体の記録領域の巾方向に延在され、記録領域
に対向される磁界放出面を備えた強磁性体で作られた磁
心部と、 この磁心部に扁平状に巻回されたコイルと、強磁性体で
作られ、前記磁界放出面と磁気的に連結されれたヨーク
部とを有し、 前記ヨーク部が下記イ）、ロ）の特徴を有する磁束帰還
プレート４と前記磁心部と前記コイルを覆う磁性板２と
から構成されることを特徴とする補助磁界印加装置。 イ）前記磁界放出面に磁気的に対応し、且つ近接して配
された磁束帰還部４ａを有することロ）当該補助磁界印
加装置の保持部材及びコイルで発生する熱の放熱板とし
て機能すること（２）前記磁束帰還プレート４と磁性板
２とが、所定時に分離される構成であることを特徴とす
る請求項１記載の補助磁界印加装置。 （３）前記磁心部が前記磁界放出面と前記コイルを巻く
部分から構成され、全体がＴ字形であることを特徴とす
る請求項１記載の補助磁界印加装置。[Scope of Claims] (1) In an auxiliary magnetic field application device that applies an auxiliary magnetic field in conjunction with a light beam to record information on a magneto-optical recording medium or erase recorded information, the recording area of the information recording medium A magnetic core part made of a ferromagnetic material and having a magnetic field emitting surface extending in the width direction of the recording area and facing the recording area, a coil wound flatly around this magnetic core part, and a coil made of a ferromagnetic material. and a yoke portion magnetically connected to the magnetic field emitting surface, the yoke portion having the following characteristics a) and b), a magnetic plate covering the magnetic core portion and the coil. An auxiliary magnetic field applying device comprising: 2. b) It has a magnetic flux return part 4a that magnetically corresponds to the magnetic field emitting surface and is arranged close to it.b) It functions as a heat dissipation plate for the heat generated by the holding member and coil of the auxiliary magnetic field application device. (2) The auxiliary magnetic field applying device according to claim 1, wherein the magnetic flux return plate 4 and the magnetic plate 2 are configured to be separated at a predetermined time. (3) The auxiliary magnetic field applying device according to claim 1, wherein the magnetic core portion is composed of the magnetic field emitting surface and a portion around which the coil is wound, and has a T-shape as a whole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16683289A JPH0334104A (en) | 1989-06-30 | 1989-06-30 | Auxiliary magnetic field applying device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16683289A JPH0334104A (en) | 1989-06-30 | 1989-06-30 | Auxiliary magnetic field applying device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0334104A true JPH0334104A (en) | 1991-02-14 |
Family
ID=15838486
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16683289A Pending JPH0334104A (en) | 1989-06-30 | 1989-06-30 | Auxiliary magnetic field applying device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0334104A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0736866A2 (en) * | 1995-04-07 | 1996-10-09 | Discovision Associates | Bias coil for magneto-optical drive |
-
1989
- 1989-06-30 JP JP16683289A patent/JPH0334104A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0736866A2 (en) * | 1995-04-07 | 1996-10-09 | Discovision Associates | Bias coil for magneto-optical drive |
| EP0736866A3 (en) * | 1995-04-07 | 1997-12-17 | Discovision Associates | Bias coil for magneto-optical drive |
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