JPS59201208A - Core for magnetic head - Google Patents

Abstract

PURPOSE:To eliminate the adverse influence of a magnetic core upon the closed magnetic path of a back gap by forming a recessed part as a brazing material reservoir in some part of the faying surface of a core block. CONSTITUTION:The core block 12 has a cut 14 for forming an window for winding insertion near its upper corner part 13, and its flat abutting part 15 and upper corner part 13 forms a stepped part of size equal to a magnetic gap (g). The upper corner part 17 of a core block 16, on the other hand, faces said upper corner 15 with a nonmagnetic film 18 of SiO2, etc., while leaving a magnetic gap (g), and the flat abutting part 19 is joined tightly to the flat abutting part 15 to form a back gas 20 which is narrow enough to ignore magnetically. Then, V grooves 21 and 22 are formed in the flat joint parts 15 and 19 of the core blocks to form the recessed part 25 as the reservoir for fused Ag brazing material 24 which binds the core blocks 12 and 16 together. Thus, the adverse influence on the closed magnetic path of the back gap is eliminated.

Description

【発明の詳細な説明】 技術分野 この発明は、磁気記録原理に基く磁気ヘッドに関するも
ので、藁記録密度が要求される傾向が顕著なＶＴＲ用磁
気へラドコアの構造改善全図る技術に属する。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a magnetic head based on magnetic recording principles, and belongs to a technology for improving the structure of magnetic helad cores for VTRs, which tend to require a high recording density.

背景技術 従来よりこの種磁気ヘッドは、高透磁率は勿論のこと、
低保磁力、高飽和磁束密度などの優れた磁気特性７備え
た磁性材料コアが用いられている。BACKGROUND ART Conventionally, this type of magnetic head has not only high magnetic permeability but also
A magnetic material core with excellent magnetic properties 7 such as low coercive force and high saturation magnetic flux density is used.

この磁性材料コアは、材質として一般にＭｎＺｎ系フェ
ライトが、上記緒特性が良好な上に、比抵抗が著しく大
で、高周波特性も良いので賞用されて来た。しかし、最
近の磁気ヘッドは、磁気記録媒体の磁性材料が、従来の
針状ゲータイト粒子から得られるγ−Ｆ　＋３２０３で
は飽和磁束密度に限界があり、Ｆｅ−ＣｏやＦｅ−Ｃｏ
−Ｎｉ　ｆ主組成とするメタル磁性粉使用が実現したの
で、これに対応する尚飽和磁束密匿全渦足するＦ　ｅ　
−３ｉ　−Ａ見全主組成とするセンダスト合金コアが実
用化されようとしている。ところが、センダスト合金コ
アは、加工性の点ではフェライトよりも低く、シかもコ
ア製作上次に述べる問題があった。Generally, MnZn-based ferrite is used as the material for this magnetic material core, and has been widely used because it not only has the above-mentioned good properties, but also has extremely high resistivity and good high-frequency properties. However, in recent magnetic heads, the magnetic material of the magnetic recording medium is γ-F + 3203 obtained from conventional acicular goethite particles, which has a limit in saturation magnetic flux density, and Fe-Co or Fe-Co
- Since the use of metal magnetic powder with the main composition of Ni f has been realized, the corresponding saturated magnetic flux-tight total vortex addition Fe
-3i -A Sendust alloy core having the entire main composition is about to be put into practical use. However, the sendust alloy core has lower workability than ferrite, and has the following problems in manufacturing the core.

すなわち１従来のフェライトは、第１図に示すように、
上隅部１の近傍にフィル巻騙挿通用窓全形成するため切
欠凹部２全設けたブロック片３の平坦突き合せ部益と、
上隅部１と対峙する上隅部５全有するブロック片６の平
坦突き合せ部７と全、接Ｎ拐である低融点ガラス８にて
接合・１堆させて組付けしている。ところがセンダスト
合金に材質変更全図ると、低融点ガラスでは濡れ性が悪
く、接層困難となる。そのため接着材としてはろう材が
考えられるが、この場合次に述べる、閉磁路にできるバ
ックギャップによる悪影響がある。すなわち、第２図に
示すようにセンダストコアブロック３’　、　６／　を
準備して、接着材にＡｇろう９を用いて、平坦突き合せ
部４　／　、　７　／を接着させ、上隅部５′の突き合
せ曲に磁気ギャップスペーサとして５ｉｆ２膜１０全被
漸して、バックギャップｈ及び磁気ギャップク全形成し
、破線１１で示す閉磁路見を設けると、短かい記録波長
で動作させる磁気ギャツブク寸法が、数千Ａに設定され
る。そして、バックギャップｂの寸法は、非磁性材であ
るＡｇろう９が、センダストコアブロック３′及び６′
へ拡散したことにより特性のそこなわれたセンダストの
層と残留したろう材の層の合計が実効寸法となり、磁気
ギャップｑと比べて無視できぬ２〜４μｍ程度になる。In other words, 1. Conventional ferrite, as shown in FIG.
A flat abutting portion of the block piece 3 is provided with the entire notch 2 near the upper corner 1 to form the entire window for inserting the fill winding,
The flat abutting part 7 of the block piece 6 having the entire upper corner part 5 facing the upper corner part 1 is joined and assembled by a low melting point glass 8 which is in contact with the entire part. However, if the material is completely changed to Sendust alloy, low melting point glass will have poor wettability, making it difficult to bond. Therefore, a brazing material may be used as the adhesive, but in this case there is an adverse effect due to the back gap formed in the closed magnetic circuit, which will be described below. That is, as shown in FIG. 2, sendust core blocks 3' and 6/ are prepared, and the flat abutting portions 4/ and 7/ are adhered using Ag solder 9 as an adhesive, and the upper corner portions 5' are bonded. When the 5if2 film 10 is completely deposited as a magnetic gap spacer on the butt curve, the back gap h and the magnetic gap are completely formed, and a closed magnetic path shown by the broken line 11 is provided, the dimensions of the magnetic gap spacer for operation at a short recording wavelength can be adjusted. , is set to several thousand A. The dimensions of the back gap b are such that the Ag solder 9, which is a non-magnetic material, is
The effective size is the sum of the sendust layer whose characteristics have been deteriorated due to diffusion into the magnetic field and the remaining brazing material layer, which is about 2 to 4 μm, which is not negligible compared to the magnetic gap q.

したがって閉磁′＃ＪＬの磁気抵抗設定が設計値より大
幅に狂ってしまう危険があった。Therefore, there was a risk that the magnetic resistance setting of the closed magnet '#JL would be significantly deviated from the designed value.

発明の開示 この発明昧・以上の技術的背景があり、磁気コアにおけ
るバックギャップσ）閉磁路への悪影９に解ン肖きせる
こと全日日ワとしたものである。DISCLOSURE OF THE INVENTION This invention is based on the above technical background, and we have been working hard all day to understand the back gap σ in the magnetic core and its negative impact on the closed magnetic circuit.

そこでこの発明は、要するに磁気コアは高透磁率とする
ためり〉グ状の一部労全除去して、磁気ギヤツブ全形成
する形態が多く、分割したコアブロック全接合して製作
され、そのため接合面に・設けられることになるバック
ギャップは接着材かろう拐であると恕影響全受けるとの
見解に基いている。よってこの発明は、コアブロックの
接合面の一部に、接層ろう材溜め用凹部全杉成すること
により、バックギャップには接着ろう材が介入しない接
合全作り著しく好適なコア接合構造とするものである。Therefore, in this invention, in order to achieve high magnetic permeability, the magnetic core is often formed by removing part of the groove-shaped part and forming the entire magnetic gear. This is based on the idea that the back gap that will be provided on the surface will be completely affected if it is made of adhesive or solder. Therefore, this invention provides a core joint structure that is extremely suitable for creating a complete joint without intervening the adhesive brazing material in the back gap by forming a recess for the bonding brazing material in a part of the joining surface of the core block. It is something.

よって、この９６明は、後述する実施例から明確となる
か、バックギャップにおける不要な磁気的損失ｋ　ｔ＋
Ｌ小とすることができ、しかもコア製作時の加工性全も
向上させることができる実用的効果７奏する。Therefore, this 96 light will become clear from the examples described later, or it will be an unnecessary magnetic loss k t+ in the back gap.
7 Practical Effects: L can be made small and workability during core manufacturing can also be improved.

発明全実施するだめの最良の形態 この発明全実施する上で最良となる形態は、つぎに説明
する実施例から明白となる。BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the invention will become clear from the embodiments described below.

第３図は、この発明の一実施例７示す磁気ヘッド用コア
の平面図である。まず１２は、その上隅部１３の近傍に
従来と同様巻線挿通用窓全形成するだめの切欠き１４全
作り、その平坦突き合せ部１５と上隅部１３とは、寸法
が磁気ギャップクに等しい段差全役けたコアブロック、
そして１６は、その上隅部１７が肉厚寸法が２で５ｉＯ
ｚ等の非磁性体膜１８全介して、上隅部１３と対峙し磁
気ギャップ９全形成せしめ、平坦突き合せ部１９が平坦
突き合せ部１５と蕾看接合して磁気的には無視出来る程
度の狭いバックギャップ２０全形成するコアブロックで
ある。さて、２１．２２は、バックギャップ２０全設定
する際に破線２３で示す閉磁路見全含まない平坦接合部
１５．１９上に摺り合せ形成したＶ溝で、これらは要す
るにコアブロック１２　、’１６７接着するＡｇろう２
４’）接着時に溶融状態で溜める四部２５′ｆ！：形成
するものである。FIG. 3 is a plan view of a core for a magnetic head showing a seventh embodiment of the present invention. First, 12 has a notch 14 completely formed in the vicinity of the upper corner 13 to form a window for winding insertion as in the conventional case, and the flat abutting part 15 and the upper corner 13 have dimensions that correspond to the magnetic gap. Core block with equal steps,
16, the upper corner 17 has a wall thickness of 2 and 5iO
The magnetic gap 9 is completely formed facing the upper corner 13 through the non-magnetic film 18 such as z, and the flat abutting part 19 is in close contact with the flat abutting part 15 to the extent that it can be ignored magnetically. It is a core block that completely forms a narrow back gap 20. Now, 21 and 22 are V grooves that are formed by sliding on the flat joint parts 15 and 19 that do not include the closed magnetic circuit shown by the broken line 23 when the back gap 20 is fully set, and these are basically the core block 12, '167 Ag soldering 2
4') Four parts 25'f stored in a molten state during bonding! : It is something that forms.

この磁気ヘッド用コアは、次に示す製作工程？経るもの
で、理想的なコア接合や力目工作業性の向上が図れる。Is this magnetic head core manufactured through the following manufacturing process? This process allows for ideal core joining and improved machining workability.

すなわち、まず第４図に示すようにセンダスト合金製で
肉厚が完成したコアの数十個分のコアブロック１２’、
１６”ｉ用意し、切欠き１４′及びＶ溝２１／　、　２
２’全形成する。つぎに第５図のように、切欠き１４′
内面にメッキ液不溶性のワックス２５全詰めて、平坦突
き合せ部１５’、１９’及びＶ溝２１’、２２’の内面
も厚さ１〜２　ｐｍ程度の薄い下地Ａｕメッキ層２６．
２７全付着させる。その後対向したｌ７研磨して第６図
に示す通りＶ溝２　］、　’　、　２２　’内のみ？残
す。さらに第７図に示すように、コアブロック１６／の
上隅部１７／上にＳｉｇｈ膜１８′？真空スパンタリン
グ法等により被層させる。それから、コアブロック１２
’、１６ゝ′全、挾み付は治具（図示省略）等により密
着させながら＼第８図に示すようにＶ溝２１’　、　２
２’全摺り合せて形成される凹部２５’へＡｇろう丸棒
２４′全嵌入させだまま、真空加熱炉中で加熱して接合
させる。That is, first, as shown in FIG. 4, several dozen core blocks 12' made of Sendust alloy and having a complete wall thickness are prepared.
16"i prepared, notch 14' and V groove 21/, 2
2' fully formed. Next, as shown in Fig. 5, cut out 14'
The inner surfaces are completely filled with wax 25 insoluble in the plating solution, and the inner surfaces of the flat abutting portions 15', 19' and the V-grooves 21', 22' are also coated with a thin base Au plating layer 26 with a thickness of about 1 to 2 pm.
27. Adhere completely. After that, the opposing l7 was polished and only the inside of the V groove 2], ', 22' was polished as shown in Fig. 6. leave. Further, as shown in FIG. 7, a Sigh film 18' is placed on the upper corner 17/ of the core block 16/. It is coated by a vacuum sputtering method or the like. Then core block 12
', 16', and when clamping, make a V-groove 21', 2 as shown in Figure 8 while tightly fitting with a jig (not shown), etc.
While the Ag solder round rod 24' is completely inserted into the recess 25' formed by rubbing the two parts together, the two are heated in a vacuum heating furnace and joined.

したがって、四部２５′は加熱接合時に平坦突き合せ部
１５’、１９’がますます密着し、バックギャップ２０
へは、Ａｇろう２４が介入しない。以上の結果得られた
コアブロック組付体２日全１一点鎖線２つで示すように
、磁気記録媒体との摺動−米は近接面金、湾曲研磨し、
さらに各々のコア肉厚に細＄３０１３０．・・・に沿っ
てスライスすれば第３図に示した磁気ヘッド用コアが得
られる。Therefore, the flat abutting parts 15' and 19' of the four parts 25' are brought into close contact with each other during heating bonding, and the back gap 20
Agrou 24 does not intervene. As shown by the two dot-dash lines for the core block assembly obtained as a result of the above, the sliding surface with the magnetic recording medium was polished with a close surface, curved, and
Furthermore, the thickness of each core is $30,130. By slicing along..., the magnetic head core shown in FIG. 3 can be obtained.

以」二の説明から、この磁気ヘッド用コアは、次に示す
優れた長所がある。From the following explanation, this magnetic head core has the following excellent advantages.

■　コアブロック’　密Ｎ　ＪＭ合でき、そのバックギ
ャップに接層材であるろう材全介在させないから、正確
な磁気回路設定が行え、磁気特性が良好で均一な磁気ヘ
ッド用コアが得られる。(2) Core block' Since dense NJM bonding is possible and no brazing material is interposed in the back gap, accurate magnetic circuit setting can be performed and a magnetic head core with good and uniform magnetic properties can be obtained.

■　ろう材溜め用四ｇｌＳｑ〕形成によりコアブロック
の接層強度は実用的に十分であり、個々のコアへ加工す
る場合でもパックギャップ全面全ろう付け１〜だ場合と
はソ同様に取扱うことができる。■ The contact strength of the core block is practically sufficient due to the formation of 4 glSq for the brazing material reservoir, and even when processing into individual cores, it can be handled in the same way as when the pack gap is fully brazed 1~. can.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図及び第２図は、この発明以前の磁気ヘッド用コア
の平面図、第３図は、この発明の一実施例７示す磁気ヘ
ッド用コアの平面図、第４図〜第８図は、そのコアブロ
ック接着又は組付加工処理全説明するだめの各工程にお
ける平面図又は斜視図である。 １２．１６．１２’、１６’・・・コアブロック、１５
　、１９　、１５’、１９’・・・接合面（平坦突き合
せ部）、２０・拳・バックギャップ′、 ２１．２２、−　、Ｖ溝、 ２４・Φ・ろう拐、 ２５＠１１１１四部、 り１１磁気ギヤツプ、 見φ・・閉磁路。 特許出願人　　　新日本電気株式会社 第３図 第　８　図1 and 2 are plan views of a magnetic head core prior to this invention, FIG. 3 is a plan view of a magnetic head core showing a seventh embodiment of the invention, and FIGS. 4 to 8 are FIG. 2 is a plan view or a perspective view of each step of the core block adhesion or assembly process, but will not be fully explained. 12.16.12', 16'...core block, 15
, 19, 15', 19'...Joint surface (flat abutting part), 20・Fist/back gap', 21.22, -, V groove, 24・Φ・Wasing, 25@1111 4 parts, Ri 11 Magnetic gap, φ...Closed magnetic path. Patent applicant: Nippon Electric Co., Ltd. Figure 3 Figure 8

Claims (1)

【特許請求の範囲】[Claims] 分割したコアブロック全接合して、環状の閉１路と、閉
磁路の−ｇ（５′ｆ！：極めて狭く欠除した磁気ギャッ
プと７有する磁気コア全形成するものにおいて、前記コ
アブロックの接合面の一部に、接着ろう材溜め用四部？
形成して、閉磁路中のバックギャップには接層ろう材が
介入しない接合全杉成すること全特徴とする磁気ヘッド
用コア。In the case where the divided core blocks are all joined to form an annular closed circuit and a closed magnetic circuit of -g (5'f!: extremely narrow magnetic gap and 7 magnetic cores), the joining of the core blocks Is there a part of the surface with four parts for the adhesive brazing filler metal reservoir?
A core for a magnetic head is characterized in that the back gap in the closed magnetic circuit is formed into a full-bond structure with no brazing filler metal intervening.