JPH0572005B2 - - Google Patents
Info
- Publication number
- JPH0572005B2 JPH0572005B2 JP57060878A JP6087882A JPH0572005B2 JP H0572005 B2 JPH0572005 B2 JP H0572005B2 JP 57060878 A JP57060878 A JP 57060878A JP 6087882 A JP6087882 A JP 6087882A JP H0572005 B2 JPH0572005 B2 JP H0572005B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- head
- substrate
- magnetic layer
- track width
- 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.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/187—Structure or manufacture of the surface of the head in physical contact with, or immediately adjacent to the recording medium; Pole pieces; Gap features
- G11B5/1871—Shaping or contouring of the transducing or guiding surface
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Magnetic Heads (AREA)
Description
【発明の詳細な説明】
本発明は、高抗磁力記録媒体に対して充分な記
録能力を有する磁気ヘツドの製造方法に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a magnetic head having sufficient recording ability for high coercive force recording media.
従来より、VTRあるいは磁気デイスク用のヘ
ツドコアにはフエライト材料が多く用いられてき
た。これは数ＭHz以上の高い周波数領域における
透磁率の高さと耐摩耗性の良好なことによるもの
である。 Traditionally, ferrite materials have often been used for head cores for VTRs or magnetic disks. This is due to the high magnetic permeability and good wear resistance in the high frequency range of several MHz or more.
ところが、近年、記録密度の向上を図るため合
金粉末、メツキあるいは蒸着等による高抗磁力記
録媒体が使われる傾向にある。 However, in recent years, there has been a tendency to use high coercive force recording media made of alloy powder, plating, vapor deposition, etc. in order to improve recording density.
しかし、従来のフエライト材料によるヘツドコ
アでは飽和磁束密度が低いため、抗磁力が1000
（Oe）を超えるような記録媒体に対する記録能力
が不充分である。 However, because the saturation magnetic flux density of the head core made of conventional ferrite material is low, the coercive force is 1000
The recording capacity for recording media exceeding (Oe) is insufficient.
そこで、従来より特殊な用途として放送用
VTRのヘツドとして使われてきた飽和磁束密度
の高いセンダストヘツドが見直されている。 Therefore, it has been used for broadcasting as a special purpose than before.
Sendust heads, which have a high saturation magnetic flux density and have been used as heads for VTRs, are being reconsidered.
本発明は、上記事情に鑑みてなされたもので、
トラツク幅を精度よく出すことができ、かつ容易
に任意のトラツク幅とすることのできる磁気ヘツ
ドの製造方法を提供するものである。 The present invention was made in view of the above circumstances, and
The present invention provides a method for manufacturing a magnetic head that can accurately determine the track width and can easily provide any desired track width.
以下、本発明の実施例を図面を参照して説明す
る。 Embodiments of the present invention will be described below with reference to the drawings.
第１図ａ，ｂは本発明の第一実施例で製造した
磁気ヘツドを示している。 Figures 1a and 1b show a magnetic head manufactured in accordance with a first embodiment of the present invention.
第１図において、１ａはフエライト材料からな
るヘツドコア半体、２ａはガラス、セラミツクス
等の非磁性基板上に高飽和磁束密度の金属磁性層
３が形成されたヘツドコア半体である。 In FIG. 1, 1a is a half head core made of a ferrite material, and 2a is a half head core in which a metal magnetic layer 3 having a high saturation magnetic flux density is formed on a nonmagnetic substrate such as glass or ceramics.
このヘツドコア半体１ａ，２ａの間には、
SiO2，Ａ2O3等からなる非磁性層７が介在され
ている。 Between these head core halves 1a and 2a,
A nonmagnetic layer 7 made of SiO 2 , A 2 O 3 or the like is interposed.
なお、非磁性層７は、ヘツドギヤツプを形成す
るもので、ヘツドギヤツプ長に相当する厚味を有
している。 The nonmagnetic layer 7 forms a head gap and has a thickness corresponding to the head gap length.
そして、ヘツドコア半体２ａは、矢印Ａの記録
媒体走行方向に対してヘツドギヤツプの後縁側に
設けられている。 The head core half 2a is provided on the rear edge side of the head gap with respect to the recording medium traveling direction of arrow A.
さらに、金属磁性層３の厚さは、使用する周波
数帯域での表皮効果によるスキンデプスの２倍程
度に設定するのが好ましい。 Furthermore, the thickness of the metal magnetic layer 3 is preferably set to about twice the skin depth due to the skin effect in the frequency band used.
しかし、長波長での形状効果によるレスポンス
のうねりが問題となる場合にはより厚くしてもよ
い。 However, if response waviness due to shape effects at long wavelengths becomes a problem, it may be made thicker.
一方、フエライト材料からなるヘツドコア半体
１ａのギヤツプ突合わせ面１a′には、巻線溝（巻
線用窓）４が形成されていて、この巻線溝４を介
してヘツドコア半体１ａ，２ａに巻線（図示せ
ず）がそれぞれ捲回される。 On the other hand, a winding groove (winding window) 4 is formed in the gap abutting surface 1a' of the head core half 1a made of ferrite material, and the head core halves 1a, 2a are connected through this winding groove 4. A winding (not shown) is wound around each of the windings (not shown).
なお、図中、２a′はヘツドコア半体２ａのギヤ
ツプ突合わせ面、５はヘツドコア半体１ａ，２ａ
のテープ当接面側に形成されたトラツク幅規制用
溝、６はこのトラツク幅規制用溝５に埋込まれた
ガラスである。 In the figure, 2a' is the gap abutting surface of the head core half 2a, and 5 is the head core half 1a, 2a.
The track width regulating groove 6 formed on the tape contacting surface side is glass embedded in the track width regulating groove 5.
第２図ａ〜ｅは上記第一実施例の磁気ヘツドの
製造方法を示している。 FIGS. 2a to 2e show a method of manufacturing the magnetic head of the first embodiment.
これによれば、まず第２図ａに示すように、ア
モルフアス、センダスト等を短冊状に加工する
か、あるいはバルクの金属磁性材料から短冊状に
加工してなる厚さ20μm〜150μm程度の高飽和磁
束密度の金属磁性層３を得る。 According to this, first, as shown in Figure 2a, a high saturation material with a thickness of about 20 μm to 150 μm is formed by processing amorphous amorphous, sendust, etc. into a strip shape, or by processing a bulk metal magnetic material into a strip shape. A metal magnetic layer 3 having a magnetic flux density is obtained.
次いで、この金属磁性層３をガラス、セラミツ
ク等からなる非磁性基板２にガラス溶着する（同
図ｂ参照）。この際、金属磁性層３の接合面（裏
面）に予めSiO2，Ａ2O3等をスパツタリング、
蒸着等の手段で付着させておくと良好な接合強度
が得られる。 Next, this metal magnetic layer 3 is glass-welded to a non-magnetic substrate 2 made of glass, ceramic, etc. (see figure b). At this time, SiO 2 , A 2 O 3 or the like is sputtered on the bonding surface (back surface) of the metal magnetic layer 3 in advance.
If it is attached by means such as vapor deposition, good bonding strength can be obtained.
そして、金属磁性層３の表面を鏡面仕上げす
る。 Then, the surface of the metal magnetic layer 3 is mirror-finished.
一方、第２図ｃに示すように、表面をダイアポ
リツシユ等で鏡面仕上げ、かつ巻線溝４を加工し
たフエライト材料からなる磁性基板１を用意す
る。 On the other hand, as shown in FIG. 2c, a magnetic substrate 1 made of a ferrite material whose surface is mirror-finished by diapolishing or the like and has winding grooves 4 formed therein is prepared.
次いで、同図ｄに示すように、磁性基板１と非
磁性基板２、金属磁性層３にブレードあるいはワ
イアーソーによりトラツク加工を施し、トラツク
幅規制用溝５を形成する。 Next, as shown in FIG. 4D, track processing is performed on the magnetic substrate 1, nonmagnetic substrate 2, and metal magnetic layer 3 using a blade or a wire saw to form track width regulating grooves 5.
この後、磁性基板１のトラツク幅規制用溝５が
形成された面と、非磁性基板２の金属磁性層３が
形成された面（トラツク幅規制用溝５が形成され
ている）との間に非磁性層７を介在させて磁性基
板１と非磁性基板２とをガラス溶着する。このと
きガラス溶着の作業温度は金属磁性層３を非磁性
基板２にガラス溶着する際の温度よりも低くす
る。 Thereafter, a gap is formed between the surface of the magnetic substrate 1 on which the track width regulating grooves 5 are formed and the surface of the nonmagnetic substrate 2 on which the metal magnetic layer 3 is formed (on which the track width regulating grooves 5 are formed). A magnetic substrate 1 and a nonmagnetic substrate 2 are glass-welded with a nonmagnetic layer 7 interposed therebetween. At this time, the working temperature for glass welding is set lower than the temperature for glass welding the metal magnetic layer 3 to the nonmagnetic substrate 2.
そして、磁性基板１と非磁性基板２とに形成さ
れたトラツク幅規制用溝５にガラス６を埋込む。 Then, glass 6 is embedded in the track width regulating grooves 5 formed in the magnetic substrate 1 and the nonmagnetic substrate 2.
さらに、第２図ｅに示すように、ヘツドコアブ
ロツク１０のフロントギヤツプブロツク（テープ
当接面）を円研磨した後、同図に示す一点鎖線に
沿つてブレード、ワイアーソーを使用して切断す
ると、第１図ａ，ｂに示すヘツドコアが得られ
る。 Furthermore, as shown in FIG. 2e, the front gear block (tape contact surface) of the head core block 10 is circularly polished, and then cut using a blade and a wire saw along the dashed line shown in the same figure. Then, the head core shown in FIGS. 1a and 1b is obtained.
第３図ａ，ｂは本発明の第二実施例で製造した
磁気ヘツドを示している。 Figures 3a and 3b show a magnetic head manufactured in accordance with a second embodiment of the present invention.
なお、図中第１図ａ，ｂに示す部分と同一部分
には同一符号を付してその説明を省略する。 In the figure, the same parts as those shown in FIGS. 1a and 1b are designated by the same reference numerals, and the explanation thereof will be omitted.
この第二実施例で製造した磁気ヘツドにあつて
は、金属磁性層３が蒸着、スパツタリング等の手
段で形成されて厚さが2μm〜20μm程度に薄く設
定され、かつ非磁性材料からなるヘツドコア半体
２ａにはトラツク幅規制用溝５が形成されていな
い点が前述した第一実施例と相違している。 In the magnetic head manufactured in this second embodiment, the metal magnetic layer 3 is formed by means such as vapor deposition or sputtering, and the thickness is set to be as thin as 2 μm to 20 μm, and the head core half is made of a nonmagnetic material. This embodiment differs from the first embodiment in that the track width regulating groove 5 is not formed in the body 2a.
また、ヘツドコアのテープ当接面と反対側の面
にはガラス溜めの切欠き１１が形成されている。 Further, a glass reservoir notch 11 is formed on the surface of the head core opposite to the tape contact surface.
第４図ａ〜ｉは上記第二実施例の磁気ヘツドの
製造方法を示している。 4a to 4i show a method of manufacturing the magnetic head of the second embodiment.
これによれば、まず第４図ａ，ｂに示すよう
に、フエライト材料からなる磁性基板１とガラ
ス、セラミツク等からなる非磁性基板２を用意
し、それぞれの表面をダイアポリツシユ等で鏡面
仕上げを行なう。 According to this, as shown in FIGS. 4a and 4b, first, a magnetic substrate 1 made of ferrite material and a non-magnetic substrate 2 made of glass, ceramic, etc. are prepared, and the surfaces of each are polished to a mirror finish by diapolishing or the like. Do the following.
次いで、同図ｃに示すように、磁性基板１の表
面にはトラツク幅規制用溝５と巻線溝４とガラス
溜めの切欠き１１とをブレードかあるいはワイア
ーソーにより加工する。 Next, as shown in FIG. 1C, track width regulating grooves 5, winding grooves 4, and glass reservoir notches 11 are formed on the surface of the magnetic substrate 1 using a blade or a wire saw.
一方、非磁性基板２の表面には、第４図ｄに示
すように、センダスト、パーマロイ等の高飽和磁
束密度の金属磁性層３を蒸着、スパツタリング等
の手段で2μm〜20μm程度の厚さに形成する。 On the other hand, as shown in FIG. 4d, on the surface of the non-magnetic substrate 2, a metal magnetic layer 3 having a high saturation magnetic flux density such as sendust or permalloy is deposited to a thickness of about 2 μm to 20 μm by means such as vapor deposition or sputtering. Form.
なお、始めに蒸着、スパツタリング等の手段で
薄い金属磁性層３を形成した後、さらにメツキに
より2μm〜20μm程度の厚さにしてもよい。 Note that after first forming the thin metal magnetic layer 3 by means such as vapor deposition or sputtering, it may be further plated to a thickness of about 2 μm to 20 μm.
そして、この後必要ならばダイアポリッシュ等
の鏡面仕上げをしてもよい。 After that, if necessary, mirror finishing such as dia polishing may be applied.
次いで、第４図ｅに示すように、エツチング加
工により磁性基板１のトラツクに対応する寸法の
トラツク幅Ｔ；トラツクピツチTpに金属磁性層
３を加工する。 Next, as shown in FIG. 4e, the metal magnetic layer 3 is etched to have a track width T and a track pitch Tp of dimensions corresponding to the tracks of the magnetic substrate 1.
なお、磁極３ａの後部ギヤツプ部はコア飽和し
ないようにトラツク幅よりも広く設定されてい
る。 Note that the rear gap portion of the magnetic pole 3a is set wider than the track width so as not to saturate the core.
そして、第４図ｆに示すように、磁性基板１の
トラツク幅規制用溝５等が形成された面と、非磁
性基板２の磁極３ａが形成された面との間に非磁
性層７を介在させ、磁性基板１と非磁性基板２を
巻線溝４と切欠き１１とに挿入したガラス棒１２
を溶融してガラス溶着することにより、ヘツドコ
アブロツク１０が得られる。 Then, as shown in FIG. 4f, a nonmagnetic layer 7 is placed between the surface of the magnetic substrate 1 on which the track width regulating grooves 5 and the like are formed and the surface of the nonmagnetic substrate 2 on which the magnetic poles 3a are formed. A glass rod 12 with a magnetic substrate 1 and a non-magnetic substrate 2 inserted into a winding groove 4 and a notch 11
The head core block 10 is obtained by melting and glass welding.
次いで、第４図ｇに示すように、このヘツドコ
アブロツク１０のテープ当接面を円研磨し、その
後同図ｈに示す一点鎖線に沿つてブレードあるい
はワイアーソーにより切断すると、第３図ａ，ｂ
に示すヘツドコアが得られる。 Next, as shown in FIG. 4g, the tape abutting surface of the head core block 10 is circularly polished, and then cut with a blade or wire saw along the dashed line shown in FIG.
The head core shown in is obtained.
なお、第４図ｅに示すようにエツチングする代
わりに、第４図ｉに示すようにブレードあるいは
ワイアーソーで金属磁性層３と、非磁性基板２と
に磁性基板１で行なつたトラツク加工と同じトラ
ツク幅、同じトラツクピツチでトラツク加工を施
してトラツク幅規制用溝５を形成してもよい。こ
の場合、ブレードで行なつたときにはバリが生じ
る問題があるが、ワイアーソーで行なつたときに
はバリの問題がなくブレード加工よりも加工歪が
少ない。このようにすると、第１図ａ，ｂで示す
ものと同じ形状となる。 Note that instead of etching as shown in FIG. 4e, the same track processing as that performed on the magnetic substrate 1 is performed on the metal magnetic layer 3 and the non-magnetic substrate 2 using a blade or wire saw as shown in FIG. 4i. The track width regulating groove 5 may be formed by performing track processing with the same track width and track pitch. In this case, there is a problem in that burrs occur when processing is performed with a blade, but when processing is performed with a wire saw, there is no problem with burrs and processing distortion is less than when processing with a blade. This results in the same shape as shown in FIGS. 1a and 1b.
第５図は上記第二実施例で製造した磁気ヘツド
と従来のフエライト磁気ヘツドのヘツド特性図で
ある。 FIG. 5 is a head characteristic diagram of the magnetic head manufactured in the second embodiment and a conventional ferrite magnetic head.
抗磁力Hc1400（Oe）の700（Oe）のテープに対
する出力は、従来のフエライト磁気ヘツドでは点
線に示すように＋3dB〜＋6dB程度であるのに対
し、本発明の第二実施例で製造した磁気ヘツドで
は実線で示すように＋10dB〜＋12dBに向上し
た。すなわち、本発明の第二実施例で製造した磁
気ヘツドでは、抗磁力１４00（Oe）程度の高抗磁
力テープに充分記録することができる。 The output for a tape with a coercive force Hc of 1400 (Oe) of 700 (Oe) is approximately +3 dB to +6 dB as shown by the dotted line in the conventional ferrite magnetic head, whereas the output of the magnetic head manufactured in the second embodiment of the present invention As shown by the solid line, the improvement was between +10dB and +12dB. That is, the magnetic head manufactured according to the second embodiment of the present invention can sufficiently record on a high coercive force tape having a coercive force of about 1400 (Oe).
以上説明したように、本発明によれば、金属磁
性層を形成した後にトラツク加工を施しているの
で、トラツク幅を精度よく出すことができる。 As explained above, according to the present invention, since the track processing is performed after forming the metal magnetic layer, the track width can be determined with high precision.
また、トラツク加工を施すことにより、任意の
トラツク幅を有する磁気ヘツドを容易に製造する
ことができる。 Further, by performing track processing, a magnetic head having an arbitrary track width can be easily manufactured.
第１図ａ，ｂは本発明の第一実施例で製造した
磁気ヘツドを示し、第１図ａはヘツドコアの平面
図、第１図ｂは正面図、第２図ａ〜ｅは本発明の
第一実施例の磁気ヘツドの製造方法を説明する説
明図、第３図ａ，ｂは本発明の第二実施例で製造
した磁気ヘツドを示し、第３図ａはヘツドコアの
平面図、第３図ｂは正面図、第４図ａ〜ｉは本発
明の第二実施例の磁気ヘツドの製造方法を説明す
る説明図、第５図はヘツド特性図である。
１……磁性基板、２……非磁性基板、１ａ，２
ａ……ヘツドコア半体、３……金属磁性層、５…
…トラツク幅規制用溝、６……ガラス、７……非
磁性層、１２……ガラス棒。
1a and 1b show a magnetic head manufactured according to the first embodiment of the present invention, FIG. 1a is a plan view of the head core, FIG. 1b is a front view, and FIGS. FIGS. 3a and 3b are explanatory diagrams explaining the manufacturing method of the magnetic head of the first embodiment, and FIGS. 3a and 3b show the magnetic head manufactured in the second embodiment of the present invention. FIG. FIG. 4b is a front view, FIGS. 4a to 4i are explanatory diagrams illustrating a method of manufacturing a magnetic head according to a second embodiment of the present invention, and FIG. 5 is a head characteristic diagram. 1...Magnetic substrate, 2...Nonmagnetic substrate, 1a, 2
a... Head core half, 3... Metal magnetic layer, 5...
...Track width regulating groove, 6...Glass, 7...Nonmagnetic layer, 12...Glass rod.
Claims (1)
属磁性層を形成し、 この金属磁性層あるいは前記金属磁性層と前記
非磁性基板にトラツク加工を施すことにより所定
間隔で並んだ複数のトラツク幅規制用溝を形成
し、 次いでフエライト材料からなる磁性基板のトラ
ツク加工が施された面と前記非磁性基板の金属磁
性層が形成された面との間にヘツドギヤツプを形
成する非磁性体層を介在させて前記磁性基板と前
記非磁性基板とを一体に接合してヘツドコアブロ
ツクを形成し、 その後このヘツドコアブロツクを前記所定間隔
で並んだ各トラツク幅規制用溝の中央位置で切断
することによりヘツドコア単体に切り分けること を特徴とする磁気ヘツドの製造方法。[Claims] 1. A metal magnetic layer having a high saturation magnetic flux density is formed on a non-magnetic substrate such as glass, and the metal magnetic layer or the metal magnetic layer and the non-magnetic substrate are tracked at predetermined intervals. A plurality of lined up track width regulating grooves are formed, and then a head gap is formed between the track-processed surface of the magnetic substrate made of ferrite material and the surface of the non-magnetic substrate on which the metal magnetic layer is formed. A head core block is formed by bonding the magnetic substrate and the non-magnetic substrate together with a non-magnetic layer interposed therebetween, and then the head core block is inserted into the center of each of the track width regulating grooves lined up at the predetermined intervals. A method for manufacturing a magnetic head, characterized in that the head core is separated into individual head cores by cutting at positions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6087882A JPS58179920A (en) | 1982-04-14 | 1982-04-14 | Magnetic head and its production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6087882A JPS58179920A (en) | 1982-04-14 | 1982-04-14 | Magnetic head and its production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58179920A JPS58179920A (en) | 1983-10-21 |
| JPH0572005B2 true JPH0572005B2 (en) | 1993-10-08 |
Family
ID=13155070
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6087882A Granted JPS58179920A (en) | 1982-04-14 | 1982-04-14 | Magnetic head and its production |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58179920A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0770018B2 (en) * | 1985-12-20 | 1995-07-31 | 株式会社日立製作所 | Magnetic erase head |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53116810A (en) * | 1977-03-22 | 1978-10-12 | Hitachi Ltd | Magnetic head core |
| JPS5514550A (en) * | 1978-07-19 | 1980-02-01 | Hitachi Ltd | Manufacture for magnetic head |
| JPS55117723A (en) * | 1979-02-28 | 1980-09-10 | Sony Corp | Magnetic head |
| JPS55157121A (en) * | 1979-05-19 | 1980-12-06 | Nippon Telegr & Teleph Corp <Ntt> | Magnetic head core |
-
1982
- 1982-04-14 JP JP6087882A patent/JPS58179920A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58179920A (en) | 1983-10-21 |
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