JPH0634251B2 - Magnetic recording detector - Google Patents
Magnetic recording detectorInfo
- Publication number
- JPH0634251B2 JPH0634251B2 JP60092650A JP9265085A JPH0634251B2 JP H0634251 B2 JPH0634251 B2 JP H0634251B2 JP 60092650 A JP60092650 A JP 60092650A JP 9265085 A JP9265085 A JP 9265085A JP H0634251 B2 JPH0634251 B2 JP H0634251B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- coil
- magnetic recording
- head
- saturable coil
- 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
- 238000001514 detection method Methods 0.000 claims description 23
- 238000004804 winding Methods 0.000 claims description 7
- 230000004907 flux Effects 0.000 claims 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 229920006395 saturated elastomer Polymers 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 238000012790 confirmation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910000889 permalloy Inorganic materials 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
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
- G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Digital Magnetic Recording (AREA)
- Recording Or Reproducing By Magnetic Means (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、磁気記録媒体に記録された磁気信号を検出す
る磁気記録検出装置に関するものである。The present invention relates to a magnetic recording detection device for detecting a magnetic signal recorded on a magnetic recording medium.
本発明は、磁気記録検出ヘッドに可飽和コイルを用い、
この可飽和コイルに直流電流を流してバイアス磁界を与
えることにより、磁気記録検出装置の製造・調整を容易
としたものである。The present invention uses a saturable coil for a magnetic recording detection head,
By supplying a bias magnetic field by passing a direct current through this saturable coil, the manufacture and adjustment of the magnetic recording detection device are facilitated.
従来の磁気記録検出装置として、本件出願人の考案にか
かる実公昭５３−４６０１２号公報に記載のようなもの
がある。この装置の磁気記録検出ヘッドは、第６図に示
すように、記録コイル巻線(1)を施した棒状磁芯(2)の尖
端に小さい穴又は溝(3)を設け、この中に検出用の可飽
和コイル(4)を配置し、この可飽和コイル(4)に永久磁石
(5)によってバイアス磁界を加えるものである。この検
出ヘッドに正方向の磁界が加わつたとき、可飽和コイル
(4)が飽和してオン信号を生じ、負方向の磁界が加わつ
たときは飽和せずオフ信号を生じるようになつており、
バイアス磁界を加えるため、可飽和コイル(4)に近接し
て小さい永久磁石(5)を配置してある。なお、(6)はヨー
クを示す。As a conventional magnetic recording detection device, there is a device described in Japanese Utility Model Publication No. 53-46012, which was devised by the present applicant. As shown in FIG. 6, the magnetic recording detection head of this device is provided with a small hole or groove (3) at the tip of a rod-shaped magnetic core (2) provided with a recording coil winding (1), and the detection is performed in this. A saturable coil (4) for the permanent magnet is placed in this saturable coil (4).
The bias magnetic field is applied by (5). When a positive magnetic field is applied to this detection head, the saturable coil
(4) is saturated to generate an ON signal, and when a negative magnetic field is applied, it is not saturated and an OFF signal is generated.
A small permanent magnet (5) is placed close to the saturable coil (4) to apply a bias field. In addition, (6) shows a yoke.
従来の磁気記録検出装置は、上述のように永久磁石によ
りバイアス磁界を加える磁気記録検出ヘツドを使用して
いたため、製造及び調整が困難で扱いにくく実用化が進
まない欠点があつた。Since the conventional magnetic recording detecting device uses the magnetic recording detecting head for applying the bias magnetic field by the permanent magnet as described above, it has a drawback that it is difficult to manufacture and adjust, it is difficult to handle, and it cannot be put into practical use.
本発明は、永久磁石を用いるのではなく、可飽和コイル
の巻線に直流電流を流すことにより、必要なバイアス磁
界を加えるようにした。The present invention does not use a permanent magnet, but applies a required bias magnetic field by passing a direct current through the winding of the saturable coil.
磁芯の尖端部の穴又は溝の中に挿入固定された可飽和コ
イルに近接して小さい永久磁石を配置する作業が不要の
ため、磁気記録検出ヘツドの製造が容易となる。また、
バイアス磁界の大きさは直流電流により決められるの
で、調整が容易となる。Since the work of disposing a small permanent magnet in the vicinity of the saturable coil inserted and fixed in the hole or groove of the tip of the magnetic core is unnecessary, the magnetic recording detection head can be easily manufactured. Also,
Since the magnitude of the bias magnetic field is determined by the direct current, adjustment becomes easy.
以下、図面により本発明の好適な実施例を説明する。 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
第１図は本発明に用いる回路要部の例を示す図、第２図
は本発明に用いる磁気記録検出ヘッドの構造及び使用状
態の例を示す部分的断面図である。FIG. 1 is a diagram showing an example of a circuit main part used in the present invention, and FIG. 2 is a partial sectional view showing an example of the structure and usage state of a magnetic recording detection head used in the present invention.
これらの図において、第６図と対応する部分には同一の
符号を付して重視説明を省略する。検出用可飽和コイル
(4)としては、例えばＩ形のパーマロイ薄板よりなる可
飽和コアに巻線を施したものを用いる。第２図におい
て、(15)は磁気記録検出ヘツドを全体として示す。同図
に示すように、本発明は、構造的には第６図のものと殆
ど同じであり永久磁石(5)がない点が異なる。(7)は、磁
気記録検出ヘッド(15)に対接させて使用するタグ板で、
鉄板(71)の上に例えばプラスチツク磁石板(72)を貼り付
けたものである。In these figures, the parts corresponding to those in FIG. Saturable coil for detection
As (4), for example, a saturable core made of an I-shaped permalloy thin plate with a winding is used. In FIG. 2, (15) shows the magnetic recording detection head as a whole. As shown in the figure, the present invention is structurally almost the same as that of FIG. 6 except that the permanent magnet (5) is not provided. (7) is a tag plate used by contacting the magnetic recording detection head (15),
For example, a plastic magnet plate (7 2 ) is attached on the iron plate (7 1 ).
第１図において、高周波発振器(8)より抵抗(9)を介して
可飽和コイル(4)に高周波電圧を加え、その両端に一定
の電圧を発生させる。可飽和コイル(4)には、直流電源
(+E)より抵抗(11)及びチョーク・コイル(12)を介して適
当な直流電流を流す。これが、従来の回路構成と異なる
点である。チョーク・コイル(12)は、高周波電流が抵抗
(11)を通つて流れるのを阻止するためのものである。可
飽和コイル(4)に加わる磁界によつて可飽和コイル(4)が
飽和するまでは、その両端電圧は変化しない。磁界が変
化して可飽和コイル(4)が飽和すると、その両端電圧は
急激に減少する。検波回路(10)は、可飽和コイル(4)両
端の電圧を検波し、電圧の変化を検知してそれに対応す
る信号（直流出力電圧）を発生する。In FIG. 1, a high frequency voltage is applied to a saturable coil (4) from a high frequency oscillator (8) via a resistor (9), and a constant voltage is generated across the high frequency voltage. DC power supply for saturable coil (4)
Appropriate DC current from (+ E) through resistor (11) and choke coil (12). This is the difference from the conventional circuit configuration. The choke coil (12) is resistant to high frequency currents.
It is intended to prevent flow through (11). The voltage across the saturable coil (4) does not change until the saturable coil (4) is saturated by the magnetic field applied to the saturable coil (4). When the magnetic field changes and the saturable coil (4) is saturated, the voltage across it saturates. The detection circuit (10) detects the voltage across the saturable coil (4), detects a change in the voltage, and generates a signal (DC output voltage) corresponding thereto.
第３図は可飽和コイル(4)の動作を示す特性曲線図で、
Ｖは可飽和コイル両端の電圧、Ｈは磁界を示す。この図
に示すように、可飽和コイルは正負の磁界について同じ
値Ｈｓで飽和する。可飽和コイルに外部からバイアス磁
界Ｈｂを加えた場合には、正磁界に対してはＨｓ−Ｈｂ
の磁界で飽和し、負磁界に対してはＨｓ＋Ｈｂの磁界で
飽和する。FIG. 3 is a characteristic curve diagram showing the operation of the saturable coil (4),
V indicates the voltage across the saturable coil, and H indicates the magnetic field. As shown in this figure, the saturable coil saturates at the same value H s for positive and negative magnetic fields. When the addition of the bias magnetic field H b from the outside to the saturable coils, for positive magnetic field H s -H b
Is saturated with a magnetic field of H s + H b with respect to a negative magnetic field.
第２図において、タグ板(7)に磁気記録検出ヘツド（以
下W/Rヘツドと略す。）(15)を対接させて記録(w)コイル
(1)に正の電流を流すと、タグ板(7)の磁石板(72)が正に
磁化され、負の電流を流すと、負に磁化される。このよ
うにタグ板(7)とW/Rヘツド(15)を対接させた状態で、可
飽和コイル(4)に適当なバイアス磁界が加えてあれば、
第３図の特性を利用することにより、正の記録に対して
は検波回路(10)がオン信号を生じ、負の記録に対しては
オフ信号を生じるように構成しうる。したがつて、W/R
ヘツド(15)は、正又は負の記録をした直後に同じ状態で
記録された信号を可飽和(R)コイル(4)により読出すこと
ができる。この場合、タグ板(7)とW/Rヘツド(15)の間隔
が変わると可飽和コイル(4)の受ける磁界の大きさが変
化するので、安定に動作させるには、適当なバイアス磁
界Ｈｂを加えることによりＨｓ＋ＨｂとＨｓ−Ｈｂの比
を大きく取ることが望ましい。In FIG. 2, a magnetic recording detection head (hereinafter abbreviated as W / R head) (15) is contacted with a tag plate (7) to record (w) a coil.
(1) in the flow positive current, magnetic plate tag plate (7) (7 2) is positively magnetized, the flow a negative current, it is magnetized in the negative. In this way, with the tag plate (7) and the W / R head (15) in contact with each other, if an appropriate bias magnetic field is applied to the saturable coil (4),
By utilizing the characteristics of FIG. 3, the detection circuit (10) can generate an ON signal for positive recording and an OFF signal for negative recording. Therefore, W / R
The head (15) can read the signal recorded in the same state immediately after positive or negative recording by the saturable (R) coil (4). In this case, since the magnitude of the magnetic field received by the saturable coil (4) changes when the distance between the tag plate (7) and the W / R head (15) changes, an appropriate bias magnetic field H is required for stable operation. adding b by H s + H b and H s -H b ratio greatly it is desirable to take.
本発明においては、可飽和コイル(4)にバイアス磁界を
加えるのに、従来のように永久磁石によつて外部から加
えるのではなく、可飽和コイル(4)自体に直流電流を流
すことにより、外部からバイアス磁界を加えたと同等の
効果を得るものである。第１図はそのバイアス回路を示
すもので、各素子の具体例を示すと次のとおりである。
高周波発振器(8)は４００kHzで出力電圧１２ppボルト、
抵抗(9)は３kΩ、可飽和コイル(4)は２４０回巻線、チ
ヨーク・コイル(12)は２mHで、抵抗(11)はバイアス電流
に対応して選定する。実施例のW/Rヘツドでは、抵抗(1
1)を通してバイアス電流を±２８mA流したとき、オン・
オフ動作点に達した。すなわち、磁界Ｈｓ（第３図）に
相当するバイアス電流が２８mAであつた。W/Rヘツドを
安定に且つ感度よく動作させるには、15〜20mAのバイア
ス電流が適当である。第１図のような方法でバイアス磁
界を加えることにより、W/Rヘツドの製作・調整が非常
に容易となつた。In the present invention, in order to apply a bias magnetic field to the saturable coil (4), instead of externally applying it with a permanent magnet as in the conventional case, by flowing a direct current in the saturable coil (4) itself, The same effect as when a bias magnetic field is applied from the outside is obtained. FIG. 1 shows the bias circuit, and specific examples of each element are as follows.
The high frequency oscillator (8) has an output voltage of 12ppV at 400kHz,
The resistance (9) is 3 kΩ, the saturable coil (4) is wound 240 times, the chioke coil (12) is 2 mH, and the resistance (11) is selected according to the bias current. In the W / R head of the example, the resistance (1
When a bias current of ± 28 mA is passed through 1), it turns on.
The off operating point has been reached. That is, the bias current corresponding to the magnetic field H s (FIG. 3) was 28 mA. A bias current of 15 to 20 mA is suitable for stable and sensitive operation of the W / R head. By applying a bias magnetic field as shown in Fig. 1, the production and adjustment of the W / R head became extremely easy.
次に、本発明の応用例について述べる。 Next, application examples of the present invention will be described.
(イ) エスコート・メモリへの応用 第４図は、自動化の進んだ工場の組立・検査を行なうラ
インにおけるエスコート・メモリに応用した例を示す平
面図である。エスコート・メモリは、コンベヤ(13)の上
を移動するパレツト(14)に情報を記録検出するためのも
のである。パレツト(14)に品物を載せ、多数のステーシ
ヨンで組立・検査を行なう場合、パレツト(14)の側面
（又は底面）にタグ板(7)を取付けておく。タグ板(7)
は、第２図ものと同様に鉄板の上に例えばゴム磁石の薄
板を貼り付けたもので、エスコート・メモリの媒体とな
るものである。各ステーシヨンでパレツト(14)が停止し
たとき、タグ板(7)に一定位置で対接するようにW/Rヘツ
ド(15)を設ける。W/Rヘツドは、必要に応じて複数個並
べる。(A) Application to escort memory Fig. 4 is a plan view showing an example of application to an escort memory in a line for assembly / inspection of a factory that is highly automated. The escort memory is for recording and detecting information on the pallet (14) moving on the conveyor (13). When placing an article on the pallet (14) and assembling / inspecting with many stations, the tag plate (7) is attached to the side surface (or bottom surface) of the pallet (14). Tag board (7)
Like in FIG. 2, is a thin plate of, for example, a rubber magnet attached on an iron plate and serves as a medium for an escort memory. A W / R head (15) is provided so as to contact the tag plate (7) at a fixed position when the pallet (14) stops at each station. Multiple W / R heads should be lined up as necessary.
パレツト(14)がステーシヨンで停止すると、W/Rヘツド
(15)がまずタグ板(7)に記録された信号を読取る。その
ステーシヨンで記録を変更する必要があるときは、同じ
状態でW/Rヘツドの記録コイル（第２図(1)）に電流を流
して信号の書替えができる。更に、書替えが終つた直後
に信号を読出して書替えの確認（チエツク）ができる。
このように信号の読出し、書込み及び確認読出しを同じ
場所で短時間に続けて行ないうることは、W/Rヘツドを
エスコート・メモリに利用するとき大きな利点となる。When the pallet (14) stops at the station, the W / R head
(15) first reads the signal recorded on the tag plate (7). When it is necessary to change the recording at that station, the signal can be rewritten by passing an electric current through the recording coil (Fig. 2 (1)) of the W / R head in the same state. Further, the signal can be read out immediately after the rewriting is finished to confirm (check) the rewriting.
The ability to read, write, and verify read signals at the same location in a short time in this manner is a great advantage when the W / R head is used as an escort memory.
(ロ) 磁気カード（又は磁気タグ）リーダへの応用磁気
カード・リーダは、ゴム磁石板又はプラスチツク磁石板
を使つた磁気カードに記録された信号の静止読取りに使
用されるもので、特に屋外や悪環境の場所で使用される
ことが多い。(B) Application to magnetic card (or magnetic tag) reader A magnetic card reader is used for static reading of signals recorded on a magnetic card using a rubber magnet plate or a plastic magnet plate, and is especially useful for outdoor use. It is often used in bad environment.
磁気カードを磁気カード・リーダに挿入して読取りの状
態で記録の書替えができれば、読取りだけの磁気カード
・リーダと違つて応用範囲が広がり、種々の新しい使い
方ができる。これまでも、磁気カードに対接して読取り
ヘツドの反対側に記録コイルを設ける方法などを試みた
が、実用化できなかつた。If a magnetic card can be inserted into a magnetic card reader to rewrite a record in a read state, unlike magnetic card readers that only read, the range of applications will expand and various new uses will be possible. Until now, a method of providing a recording coil on the opposite side of the reading head so as to be in contact with the magnetic card has been tried, but it has not been practically used.
しかるに、本発明のW/Rヘツドを使用すると、上述のエ
スコート・メモリの場場合と同様に信号の書替え読取り
が容易にできる。第５図は、磁気カード・リーダの構成
を示す一部断面図である。W/Rヘツド(15)を鉄板(16)の
上にこれと一定の間隙をおいて配列し、その間隙に磁気
カード(17)を出し入れする構造である。この場合は、W/
Rヘツド(15)と磁気カード(17)の間隔が小さくて一定で
あるため、エスコート・メモリの場合より更に記録読取
りが安定して容易である。However, by using the W / R head of the present invention, rewriting and reading of signals can be easily performed as in the case of the escort memory described above. FIG. 5 is a partial cross-sectional view showing the structure of the magnetic card reader. The structure is such that the W / R head (15) is arranged on the iron plate (16) with a certain gap therebetween, and the magnetic card (17) is taken in and out of the gap. In this case, W /
Since the distance between the R head (15) and the magnetic card (17) is small and constant, recording and reading are more stable and easier than in the case of the escort memory.
以上説明したとおり、本発明によれば、製造及び調整が
容易で扱いやすく実用化の容易な磁気記録検出装置を得
ることができる。しかも、信号の読出し、書込み及び確
認読出しを同じ場所で短時間に続けて行なうことが可能
であるため、この種の磁気記録検出装置の応用範囲を著
しく拡大することができる。As described above, according to the present invention, it is possible to obtain a magnetic recording detection device which is easy to manufacture and adjust, easy to handle, and easy to put into practical use. Moreover, since the signal reading, writing and confirmation reading can be continuously performed at the same place in a short time, the application range of this type of magnetic recording detection device can be remarkably expanded.
第１図は本発明に用いる回路要部の例を示す図、第２図
は本発明に用いる磁気記録検出(W/R)ヘツドの製造及び
使用状態の例を示す部分的断面図、第３図は可飽和コイ
ルの動作特性曲線図、第４図は本発明のエスコート・メ
モリへの応用例を示す平面図、第５図は本発明の磁気カ
ード（又は磁気タグ）リーダへの応用例を示す一部断面
図、第６図は従来の磁気記録検出ヘツドの例を示す部分
的断面図である。 (1)……巻線、(2)……棒状磁芯、(3)……穴又は溝、(4)
……可飽和コイル、(15)……磁気記録検出ヘツド、(+E,
11,12)……直流電流を流す手段、（８，９）……高周波
電圧を加える手段、(10)……可飽和コイル両端電圧を検
知する手段。FIG. 1 is a diagram showing an example of a main part of a circuit used in the present invention, and FIG. 2 is a partial sectional view showing an example of manufacturing and use states of a magnetic recording detection (W / R) head used in the present invention. FIG. 4 is an operating characteristic curve diagram of a saturable coil, FIG. 4 is a plan view showing an application example of the present invention to an escort memory, and FIG. 5 is an application example of a magnetic card (or magnetic tag) reader of the present invention. FIG. 6 is a partial cross-sectional view, and FIG. 6 is a partial cross-sectional view showing an example of a conventional magnetic recording detection head. (1) …… winding, (2) …… rod-shaped magnetic core, (3) …… hole or groove, (4)
…… Saturable coil, (15) …… Magnetic recording detection head, (+ E,
11,12) ... Means for passing DC current, (8,9) ... Means for applying high frequency voltage, (10) ... Means for detecting voltage across saturable coil.
Claims (1)
に穴または溝(3)を設け、この穴または溝の中に棒状磁
芯の軸方向に並行な磁束を検出するための可飽和コイル
(4)を挿入固定した磁気記録検出ヘッド(15)と、上記可
飽和コイルの巻線に高周波電圧を加える手段(8)と、上
記可飽和コイル両端の電圧の変化を検知する手段(10)と
を備えた磁気記録検出装置において、 上記可飽和コイルの巻線にバイアス磁界用直流電流を流
す手段（＋Ｅ）を備えたことを特徴とする磁気記録検出
装置。1. A hole or groove (3) is provided at the tip of a rod-shaped magnetic core (2) having a recording winding (1), and magnetic flux parallel to the axial direction of the rod-shaped magnetic core is provided in the hole or groove. Saturable coil for detecting
Magnetic recording detection head (15) with (4) inserted and fixed, means (8) for applying a high frequency voltage to the winding of the saturable coil, and means (10) for detecting a change in voltage across the saturable coil A magnetic recording detection device including: a magnetic recording detection device including means (+ E) for supplying a bias magnetic field direct current to the winding of the saturable coil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60092650A JPH0634251B2 (en) | 1985-04-30 | 1985-04-30 | Magnetic recording detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60092650A JPH0634251B2 (en) | 1985-04-30 | 1985-04-30 | Magnetic recording detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61250804A JPS61250804A (en) | 1986-11-07 |
| JPH0634251B2 true JPH0634251B2 (en) | 1994-05-02 |
Family
ID=14060332
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60092650A Expired - Lifetime JPH0634251B2 (en) | 1985-04-30 | 1985-04-30 | Magnetic recording detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0634251B2 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5346012U (en) * | 1976-09-24 | 1978-04-19 | ||
| JPS5437643A (en) * | 1977-08-31 | 1979-03-20 | Fujitsu Ltd | Magnetic discrimination device for paper |
-
1985
- 1985-04-30 JP JP60092650A patent/JPH0634251B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61250804A (en) | 1986-11-07 |
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| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
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| EXPY | Cancellation because of completion of term |