JP3291923B2 - Magnetic sensor device - Google Patents
Magnetic sensor deviceInfo
- Publication number
- JP3291923B2 JP3291923B2 JP16994194A JP16994194A JP3291923B2 JP 3291923 B2 JP3291923 B2 JP 3291923B2 JP 16994194 A JP16994194 A JP 16994194A JP 16994194 A JP16994194 A JP 16994194A JP 3291923 B2 JP3291923 B2 JP 3291923B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- magnetic field
- detected
- sensor device
- information
- 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 - Fee Related
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- Measuring Magnetic Variables (AREA)
- Inspection Of Paper Currency And Valuable Securities (AREA)
- Magnetic Heads (AREA)
- Hall/Mr Elements (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、紙幣上に設置された紙
幣識別用の微小磁性体や、ＩＤカード等の紙葉状媒体に
設置された磁気コードや、ガスボンベ等のタグに設置さ
れる磁性情報を検出する高分解能型の磁気センサ装置に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic material installed on a banknote, a micromagnetic material for identifying a banknote, a magnetic code installed on a sheet-like medium such as an ID card, and a magnetic tag installed on a tag such as a gas cylinder. The present invention relates to a high-resolution magnetic sensor device for detecting information.
【０００２】[0002]
【従来の技術】紙幣や磁気カード等に磁性体によって設
置されている情報を検出する磁気センサ装置が情報処理
装置の分野やその類似分野に広く用いられている。この
種の磁気センサ装置は、図７の（ａ）に示すように、永
久磁石（磁気バイアス用マグネット）１の上面に１対の
磁気抵抗素子２ａ，２ｂを装着したもので、この磁気抵
抗素子２ａ，２ｂは図８に示すように直列に接続され、
この直列回路の一方側を電源ラインに接続し、他端側を
グランドラインに接続して、分圧回路とし、磁気抵抗素
子２ａ，２ｂの直列接続部から信号取り出し部を引き出
したものである。2. Description of the Related Art A magnetic sensor device for detecting information provided on a bill, a magnetic card, or the like by a magnetic material is widely used in the field of information processing apparatuses and similar fields. This type of magnetic sensor device has a pair of magnetoresistive elements 2a and 2b mounted on the upper surface of a permanent magnet (magnet for magnetic bias) 1 as shown in FIG. 2a and 2b are connected in series as shown in FIG.
One end of this series circuit is connected to a power supply line, and the other end is connected to a ground line to form a voltage dividing circuit, and a signal extraction section is drawn from a series connection of the magnetoresistive elements 2a and 2b.
【０００３】この磁気センサ装置は被検出体３の走行経
路上（走行空間）に設置され、磁性体が設置されている
被検出体３が磁気抵抗素子２ａの上側を対向して通過す
るときに、永久磁石１のバイアス磁界が磁気抵抗素子２
ａを集中して通過する結果、磁気抵抗素子２ａの磁気抵
抗が大きく変化し、磁気センサ装置から図７の（ｂ）に
示すように上側に凸となる出力波形の信号が得られ、次
に、被検出体３が磁気抵抗素子２ｂに対向する位置に来
たときに、今度は、永久磁石１のバイアス磁界が磁気抵
抗素子２ｂ側を集中して通過する結果、磁気抵抗素子２
ｂの磁気抵抗が大きく変化し、これにより、磁気センサ
装置から下に凸となる出力波形の時系列信号が得られ
る。この磁気センサ装置の出力信号を解析することによ
り、紙幣や磁気カード等の紙葉状媒体に設置されている
磁性体の情報が読み取られる。[0003] This magnetic sensor device is installed on the traveling path (traveling space) of the object 3 to be detected, and when the object 3 on which the magnetic material is installed passes over the magnetoresistive element 2a in opposition. The bias magnetic field of the permanent magnet 1 is
As a result, the magnetic resistance of the magnetoresistive element 2a greatly changes, and a signal having an output waveform that is upwardly convex as shown in FIG. 7B is obtained from the magnetic sensor device. When the detection target 3 comes to a position facing the magnetoresistive element 2b, the bias magnetic field of the permanent magnet 1 passes through the magnetoresistive element 2b in a concentrated manner.
The magnetic resistance of b greatly changes, whereby a time-series signal having an output waveform protruding downward from the magnetic sensor device is obtained. By analyzing the output signal of the magnetic sensor device, information on a magnetic material installed on a paper-like medium such as a bill or a magnetic card is read.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、この種
の磁気センサ装置の如く、被検出体３を走行経路に沿っ
て搬送する方式のものは、被検出体３と磁気抵抗素子２
ａ，２ｂとの隙間間隔を一定に保持するのが非常に困難
である。周知のように、永久磁石１から発せられるバイ
アス磁界は分散形となるため、前記隙間間隔が変動する
と、被検出体３を横切るバイアス磁界の幅が変動する結
果、被検出体が連続して走行すると、磁気センサ装置の
出力波形が乱れ、分解能が低下し、検出の信頼性が損な
われるという問題が生じる。However, such a type of magnetic sensor device that transports the object 3 along a traveling path, such as a magnetic sensor device of this type, uses the object 3 and the magnetoresistive element 2
It is very difficult to maintain a constant gap between a and 2b. As is well known, since the bias magnetic field generated from the permanent magnet 1 is of a dispersed type, if the gap interval fluctuates, the width of the bias magnetic field crossing the detection target 3 fluctuates, so that the detection target continuously travels. Then, there arises a problem that the output waveform of the magnetic sensor device is disturbed, the resolution is reduced, and the reliability of detection is impaired.
【０００５】本出願人は、前記隙間間隔の変動に起因す
る分解能の低下を防止するものとして、図５に示すよう
な磁気センサ装置を特許出願によって提案している。こ
の提案装置は、筐体４の上下中間部に被検出体３の走行
空間５を設け、この走行空間の下側の筐体４内には、永
久磁石１を配設し、この永久磁石１の上面には必要に応
じサブストレート（図示せず）を介して分圧回路を形成
している磁気抵抗素子２ａ，２ｂを配置し、磁気抵抗素
子２ａ，２ｂの上面を走行空間５に臨ませている。The present applicant has proposed a magnetic sensor device as shown in FIG. 5 by applying for a patent as a device for preventing a decrease in resolution due to the fluctuation of the gap. In the proposed device, a traveling space 5 for the detection target 3 is provided in the upper and lower middle portions of a housing 4, and a permanent magnet 1 is disposed in the housing 4 below the traveling space. The magnetoresistive elements 2a and 2b forming a voltage dividing circuit are disposed on the upper surface of the device as necessary through a substrate (not shown), and the upper surfaces of the magnetoresistive elements 2a and 2b face the traveling space 5. ing.
【０００６】走行空間５の上側の筐体４内には、形状磁
気異方性板６を立設状に配置し、形状磁気異方性板６の
底面を磁気抵抗素子２ａ，２ｂ間に対向させている。In the housing 4 above the traveling space 5, a shaped magnetic anisotropic plate 6 is arranged upright, and the bottom surface of the shaped magnetic anisotropic plate 6 is opposed between the magnetoresistive elements 2a and 2b. Let me.
【０００７】このように、形状磁気異方性板６を配置す
ることにより、永久磁石１から出るバイアス磁界は形状
磁気異方性板６に集中して、磁気抵抗素子２ａ，２ｂ間
に、永久磁石１から形状磁気異方性板６に向かう磁界に
よって磁気障壁を作り出し、走行空間５を通る被検出体
３と磁気抵抗素子２ａ，２ｂとの隙間間隔の変動が生じ
ても、被検出体３を横切る磁界の幅が変動しないように
して分解能の低下を来さないようにしようとするもので
ある。By arranging the shape magnetic anisotropic plate 6 in this manner, the bias magnetic field emitted from the permanent magnet 1 is concentrated on the shape magnetic anisotropic plate 6 and is permanently located between the magnetoresistive elements 2a and 2b. A magnetic barrier is created by the magnetic field directed from the magnet 1 to the shape magnetic anisotropic plate 6, and even if the gap between the detection target 3 passing through the traveling space 5 and the magnetoresistive elements 2a and 2b fluctuates, the detection target 3 In this case, the width of the magnetic field crossing the line does not fluctuate so that the resolution does not decrease.
【０００８】しかしながら、図６に示すように、永久磁
石１から形状磁気異方性板６に向かう磁界は、必ずしも
形状磁気異方性板６の底面に集中するとは限らず、永久
磁石１から出た磁界が外側に膨らんで分散形（発散形）
になった後、形状磁気異方性板６の両側面Ｇ，Ｈに入り
込むものが生じ、このときの分解能は、被検出体３の走
行通路７を磁界８，９が横切るＥＦの幅によって定ま
る。この形状磁気異方性板６の両側面に入り込む分散形
の磁界が生じると、分解能を定めるＥＦの幅が大きくな
り、期待したほど分解能の改善が図れないという問題が
ある。However, as shown in FIG. 6, the magnetic field traveling from the permanent magnet 1 to the shape magnetic anisotropic plate 6 is not always concentrated on the bottom surface of the shape magnetic anisotropic plate 6, and Magnetic field expands outward and disperses (diverges)
After that, a part of the magnetic anisotropic plate 6 penetrates both sides G and H, and the resolution at this time is determined by the width of the EF that the magnetic fields 8 and 9 cross the traveling passage 7 of the detection target 3. . When a dispersive magnetic field that enters both side surfaces of the shape magnetic anisotropic plate 6 occurs, the width of the EF that determines the resolution increases, and there is a problem that the resolution cannot be improved as expected.
【０００９】また、最近においては、被検出体３の高速
走行化が図られており、このような被検出体の高速走行
を行うためには、被検出体３と磁気抵抗素子２ａ，２ｂ
間の間隙を大きくしなければならない。例えば、被検出
体３の低速走行においては、被検出体３と磁気抵抗素子
２ａ，２ｂ間の間隙を、例えば0.1 mmと小さくできる
が、高速走行を行う場合には、例えば４mmという如く、
被検出体３と磁気抵抗素子２ａ，２ｂ間の目詰まり等を
防ぐために、間隙を大きく取らなければならず、そうす
ると、必然的に永久磁石１から形状磁気異方性板６に向
かう磁界は分散形となるために、外側に膨らむこととな
り、分解能が低下するという問題が生じる。Recently, the speed of the detected object 3 has been increased. In order to perform such high-speed running of the detected object, the detected object 3 and the magnetoresistive elements 2a, 2b are required.
The gap between them must be large. For example, when the detected object 3 runs at a low speed, the gap between the detected object 3 and the magnetoresistive elements 2a and 2b can be reduced to, for example, 0.1 mm.
In order to prevent clogging or the like between the detection target 3 and the magnetoresistive elements 2a and 2b, a large gap must be provided, so that the magnetic field from the permanent magnet 1 to the shaped magnetic anisotropic plate 6 is inevitably dispersed. Due to the shape, it swells outward, which causes a problem that the resolution is reduced.
【００１０】さらに、ガスボンベ等のタグに設置された
磁性コードを読み取るような場合には、前記図５に示し
た構造の磁気センサ装置では、走行空間５の下面側に磁
気抵抗素子２ａ，２ｂを配置する構成であるため、ガス
ボンベ等のタグに磁気抵抗素子２ａ，２ｂの検出面をあ
てがうことができず、タグ等の露出表面の磁性コードを
読み取ることが困難となる。この点、図７に示したタイ
プの磁気センサ装置では磁気抵抗素子２ａ，２ｂの検出
面側をタグに対向させて磁性コードを読み取ることはで
きるが、前記したように、永久磁石１から磁気抵抗素子
２ａ，２ｂを通る磁界は分散形となるために、分解能が
落ち、コード読み取りの信頼性の上で問題がある。In the case of reading a magnetic code installed on a tag such as a gas cylinder, the magnetic sensor device having the structure shown in FIG. Because of the arrangement, the detection surfaces of the magnetoresistive elements 2a and 2b cannot be applied to a tag such as a gas cylinder or the like, and it becomes difficult to read a magnetic code on an exposed surface of the tag or the like. In this respect, in the magnetic sensor device of the type shown in FIG. 7, the magnetic code can be read with the detection surfaces of the magnetoresistive elements 2a and 2b facing the tag. Since the magnetic field passing through the elements 2a and 2b is of a dispersed type, the resolution is reduced and there is a problem in the reliability of code reading.
【００１１】本発明は上記従来の課題を解決するために
なされたものであり、その目的は、被検出体と磁気検出
面との間隙を大きくしても、分解能の高い磁気情報の検
出が可能であり、さらに、タグ等の表面に形成されてい
る磁性情報の読み取り検出も容易、かつ、正確に行うこ
とができる磁気センサ装置を提供することにある。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to enable high-resolution detection of magnetic information even when a gap between a detection object and a magnetic detection surface is increased. Another object of the present invention is to provide a magnetic sensor device capable of easily and accurately reading and detecting magnetic information formed on the surface of a tag or the like.
【００１２】[0012]
【課題を解決するための手段】本発明は上記目的を達成
するために、次のように構成されている。すなわち、第
１の発明は、マグネットと、該マグネットによって磁気
バイアスされた分圧回路を形成する１対以上の感磁性素
子と、で構成され、該感磁性素子に対向する被検出体に
よって変化する磁気バイアス変化量を検出する磁気セン
サにおいて、前記対をなす各感磁性素子の境界部と被検
出体間に該マグネットの磁束経路を区画する磁界分離ヨ
ークが設けられていることを特徴として構成されてい
る。The present invention is configured as follows to achieve the above object. That is, the first invention includes a magnet and one or more pairs of magnetically sensitive elements forming a voltage dividing circuit magnetically biased by the magnet, and is changed by an object to be detected facing the magnetically sensitive element. In the magnetic sensor for detecting the amount of change in magnetic bias, a magnetic field separating yoke for defining a magnetic flux path of the magnet is provided between a boundary between the pair of magnetically sensitive elements and the object to be detected. ing.
【００１３】また、第２の発明は、前記第１の発明にお
ける被検出体の磁気情報を検出する感磁性素子対が複数
配列配置され、この磁気情報を検出する各感磁性素子対
の検出信号を順次切り替えて取り出す情報検出手段が設
けられていることを特徴として構成されている。According to a second aspect of the present invention, in the first aspect, a plurality of magnetic sensitive element pairs for detecting magnetic information of the object to be detected are arranged and a detection signal of each magnetic sensitive element pair for detecting the magnetic information is provided. Are sequentially switched to extract information.
【００１４】さらに、第３の発明は、前記第１の発明又
は第２の発明の構成において、感磁性素子は磁気抵抗素
子によって構成されていることを特徴として構成されて
いる。Further, a third invention is characterized in that, in the configuration of the first invention or the second invention, the magnetic sensitive element is constituted by a magnetoresistive element.
【００１５】[0015]
【作用】上記構成の第１の発明において、例えば、セン
サ検出面に間隙を介して被検出体が通過するような場
合、被検出体の磁気情報が磁性材料によって与えられて
いる場合には、対を成す感磁性素子の一方側に磁気情報
が対向したときには、バイアスマグネットからその一方
側の感磁性素子を通る磁界は対向する磁気情報に注ぎ込
み、バイアスマグネットから他方側の感磁性素子を通る
磁界は磁界ヨークによって遮られ、この磁界が被検出体
の磁気情報側に入り込むことによって生じるクロストー
クが防止される。In the first aspect of the present invention, for example, when the object to be detected passes through the sensor detection surface via a gap, when the magnetic information of the object to be detected is given by a magnetic material, When magnetic information opposes one side of a pair of magnetic elements, the magnetic field passing from the bias magnet to the magnetic element on one side is poured into the opposing magnetic information, and the magnetic field passing from the bias magnet to the magnetic element on the other side. Is blocked by the magnetic field yoke, and crosstalk caused by the magnetic field entering the magnetic information side of the object to be detected is prevented.
【００１６】被検出体が移動して他方側の感磁性素子に
対向すると、今度は、その他方側の感磁性素子を通る磁
界が磁気情報に注ぎ込み、一方側の感磁性素子を通る磁
界は磁界ヨークに遮られることでクロストークが防止さ
れる。このように、被検出体の磁気情報が一方側の感磁
性素子に対向する位置から他方側の感磁性素子に対向す
る位置へ移動する毎に、磁気情報に注ぎ込まれる磁界は
一方側の感磁性素子を通る磁界から他方側の感磁性素子
を通る磁界にシャープに切り替えられる。When the object to be detected moves and faces the magnetic element on the other side, the magnetic field passing through the magnetic element on the other side is poured into the magnetic information, and the magnetic field passing through the magnetic element on one side is the magnetic field. Crosstalk is prevented by being blocked by the yoke. As described above, each time the magnetic information of the detected object moves from the position facing the magnetic sensing element on one side to the position facing the magnetic sensing element on the other side, the magnetic field poured into the magnetic information changes the magnetic sensitivity of the one side. The magnetic field passing through the element can be sharply switched to the magnetic field passing through the magnetically sensitive element on the other side.
【００１７】被検出体の磁気情報を検出する感磁性素子
対が複数配列配置されている第２の発明にあっては、各
感磁性素子対の磁気検出信号を情報検出手段により順次
切り替えて取り出すことで、多チャンネルの磁気検出信
号の処理が行われる。In the second invention, in which a plurality of magnetic sensitive element pairs for detecting magnetic information of the object to be detected are arranged, a magnetic detection signal of each magnetic sensitive element pair is sequentially switched and extracted by the information detecting means. Thus, multi-channel magnetic detection signal processing is performed.
【００１８】[0018]
【実施例】以下、本発明の実施例を図面に基づいて説明
する。なお、本実施例の説明において、従来例および提
案例と同一の名称部分には同一符号を付し、その重複説
明は省略する。図１には本発明に係る磁気センサ装置の
第１の実施例が示されている。この実施例も、前記提案
例と同様に、筐体４の内部にバイアスマグネットとして
の永久磁石１を収容固定し、この永久磁石１の磁極表面
に直接、あるいは微小間隙を介して１対の感磁性素子と
しての磁気抵抗素子２ａ，２ｂを隣接して並置固定し、
図８に示すような磁気抵抗素子２ａ，２ｂの分圧回路を
形成している。Embodiments of the present invention will be described below with reference to the drawings. In the description of the present embodiment, the same reference numerals are assigned to the same names as those in the conventional example and the proposal example, and the duplicate description thereof will be omitted. FIG. 1 shows a first embodiment of the magnetic sensor device according to the present invention. In this embodiment, similarly to the above-described proposal, a permanent magnet 1 as a bias magnet is housed and fixed inside a housing 4, and a pair of senses is directly provided on the magnetic pole surface of the permanent magnet 1 or through a minute gap. Magnetoresistance elements 2a and 2b as magnetic elements are fixed side by side adjacently,
A voltage dividing circuit of the magnetoresistive elements 2a and 2b is formed as shown in FIG.
【００１９】本実施例が提案例と異なる特徴的なこと
は、筐体４の表面10側を被検出体３の検出面と成し、こ
の検出面と磁気抵抗素子２ａ，２ｂ間に、磁界分離ヨー
ク11が設けられていることである。この磁界分離ヨーク
11は提案例の形状磁気異方性板６と同形状に形成され、
筐体４内に埋設されて１対の磁気抵抗素子２ａ，２ｂの
境界部に立設されている。The present embodiment is different from the proposed embodiment in that the surface 10 of the housing 4 is formed as a detection surface of the object 3 and a magnetic field is applied between the detection surface and the magnetoresistive elements 2a and 2b. That is, a separation yoke 11 is provided. This magnetic field separating yoke
11 is formed in the same shape as the shape magnetic anisotropic plate 6 of the proposed example,
It is buried in the housing 4 and stands upright at the boundary between the pair of magnetoresistive elements 2a and 2b.
【００２０】磁界分離ヨーク11はパーマロイ、純鉄、珪
素鋼板等で代表される一連の軟磁性材料を用いて作製さ
れている。なお、磁気抵抗素子２ａ，２ｂはＩｎＳｂ，
ＩｎＡｓ，ＧａＡｓ等の移動度（モビリティ）の大きな
適宜の半導体材料を用いて構成されている。The magnetic field separating yoke 11 is made of a series of soft magnetic materials represented by permalloy, pure iron, silicon steel plate and the like. Note that the magnetoresistive elements 2a and 2b are InSb,
It is formed using an appropriate semiconductor material having a high mobility (mobility) such as InAs or GaAs.
【００２１】この実施例は上記のように構成されてお
り、次にその作用を説明する。図２に示すように、被検
出体３が矢印方向に移動して、被検出体３が磁気抵抗素
子２ａに対向すると、永久磁石１から磁気抵抗素子２ａ
を通って発せられる磁界（磁束）は、対向する被検出体
３に向けてほぼ真直の経路を辿って被検出体３に入り込
む。一方、磁気抵抗素子２ｂを通る永久磁石１の磁界
は、その対向側に被検出体がない状態では分散形とな
る。This embodiment is constructed as described above, and its operation will now be described. As shown in FIG. 2, when the object 3 moves in the direction of the arrow and the object 3 faces the magnetoresistive element 2a, the permanent magnet 1 moves the magnetoresistive element 2a.
The magnetic field (magnetic flux) emitted through the object 3 enters the object 3 following a substantially straight path toward the object 3 to be detected. On the other hand, the magnetic field of the permanent magnet 1 passing through the magnetoresistive element 2b is of a dispersed type when there is no object to be detected on the opposite side.
【００２２】本実施例では、磁気抵抗素子２ａ，２ｂの
境界部に磁界分離ヨーク11が立設されることで、磁気抵
抗素子２ａの磁界分離ヨーク11寄りを通る磁界は磁界分
離ヨーク11にガイドされて真直方向を向き、被検出体３
に入り込む。一方、磁気抵抗素子２ｂの磁界分離ヨーク
寄りを通る磁界は磁界分離ヨーク11により遮られ、被検
出体３に入り込むのが遮断される結果、磁気抵抗素子２
ｂを通る磁界が被検出体３に入り込むことによって発生
するクロストークを防止できる。In the present embodiment, the magnetic field separating yoke 11 is provided upright at the boundary between the magnetoresistive elements 2a and 2b, so that the magnetic field passing near the magnetic field separating yoke 11 of the magnetoresistive element 2a is guided to the magnetic field separating yoke 11. The object 3
Get into it. On the other hand, the magnetic field passing near the magnetic field separating yoke of the magnetoresistive element 2b is blocked by the magnetic field separating yoke 11 and is blocked from entering the object 3 to be detected.
Crosstalk generated when a magnetic field passing through b enters the detection target 3 can be prevented.
【００２３】図２の状態から、被検出体３がさらに矢印
方向に移動し、被検出体３が磁気抵抗素子２ｂに対向す
る位置になると、今度は磁気抵抗素子２ａと２ｂを通る
磁界の分布パターンが逆になり、磁気抵抗素子２ｂを通
る磁界は被検出体３にほぼ真直な経路を辿って入り込
み、磁気抵抗素子２ａを通る磁界は分散形となり、磁界
分離ヨーク11寄りの磁界は磁界分離ヨーク11によって遮
断されて被検出体３に入り込むことが防止される。From the state shown in FIG. 2, when the object 3 moves further in the direction of the arrow and the object 3 comes to a position facing the magnetoresistive element 2b, the distribution of the magnetic field passing through the magnetoresistive elements 2a and 2b is obtained. The pattern is reversed, the magnetic field passing through the magnetoresistive element 2b enters the detection target 3 along a substantially straight path, the magnetic field passing through the magnetoresistive element 2a is of a dispersed type, and the magnetic field near the magnetic field separating yoke 11 is It is prevented from being blocked by the yoke 11 and entering the detection target 3.
【００２４】このように、本実施例では、磁気抵抗素子
２ａ，２ｂの境界部に形状磁気異方性板と同等な磁界分
離ヨーク11を立設したことで、磁気抵抗素子２ａを通る
磁界と磁気２ｂを通る磁界とが効果的に分離されること
となり、これにより、磁気抵抗素子２ａ, ２ｂ間の所謂
クロストークが防止され、被検出体３の磁気情報が正確
に、かつ、高感度の下で検出することが可能となる。As described above, in this embodiment, the magnetic field separating yoke 11 equivalent to the shape magnetic anisotropic plate is provided upright at the boundary between the magnetoresistive elements 2a and 2b, so that the magnetic field passing through the magnetoresistive element 2a is reduced. The magnetic field passing through the magnet 2b is effectively separated, thereby preventing so-called crosstalk between the magnetoresistive elements 2a and 2b, and the magnetic information of the detection target 3 is accurately and highly sensitive. It can be detected below.
【００２５】また、本実施例では、検出面と磁気抵抗素
子２ａ，２ｂ間に磁界分離ヨーク11を配置する構成とし
たものであるから、検出面から被検出体３に向かう磁界
は分散形ではなく、真直方向に集中する結果、被検出体
３を含む実質的な磁気回路のレラクタンスが被検出体３
が磁気抵抗素子２ａに対向して次に磁気抵抗素子２ｂに
対向するまでの間に変化し、これによって各磁気抵抗素
子２ａ，２ｂを通る磁界がシャープに切り替わり変化
し、しかも、磁気情報の検出面と被検出体との間隙が、
例えば４mmという如く大きくなっても、磁界の集中効果
を保つことができ、これらにより、磁気抵抗素子２ａ,
２ｂ間のクロストークが防止されて、被検出体３の磁気
情報の検出が高精度の下で行われることとなり、最近の
被検出体３の高速走行にも十分応え得るものとなる。In this embodiment, since the magnetic field separating yoke 11 is arranged between the detection surface and the magnetoresistive elements 2a and 2b, the magnetic field from the detection surface to the object 3 is of a distributed type. However, as a result, the reluctance of the substantial magnetic circuit including the object 3 is reduced.
Changes between before and after opposing the magnetoresistive element 2a and next opposing to the magnetoresistive element 2b, whereby the magnetic field passing through each of the magnetoresistive elements 2a and 2b switches sharply and changes. The gap between the surface and the object to be detected is
For example, even if it becomes as large as 4 mm, the effect of concentrating the magnetic field can be maintained.
Crosstalk between 2b is prevented, and the magnetic information of the detected object 3 is detected with high accuracy, which can sufficiently respond to recent high-speed running of the detected object 3.
【００２６】さらに、本実施例によれば、筐体４の表面
10をセンサ検出面としたものであるから、このセンサ検
出面を、例えばガスボンベ等のタグに近接してあてがう
ことにより、タグに設置されている磁気情報を確実に検
出することが可能となり、前記図５に示した提案例のよ
うに、筐体４の中間部に被検出体３の走行通路７を設け
た構成の磁気センサ装置によっては困難であったタグ等
の磁気設置情報の読み取りが非常に容易となる。Further, according to the present embodiment, the surface of the housing 4
Since 10 is a sensor detection surface, by applying this sensor detection surface in close proximity to a tag such as a gas cylinder, it is possible to reliably detect magnetic information installed on the tag, As in the proposal example shown in FIG. 5, it is difficult to read magnetic installation information of a tag or the like, which is difficult with a magnetic sensor device having a configuration in which the traveling path 7 of the detection target 3 is provided in an intermediate portion of the housing 4. Will be easier.
【００２７】図３は、磁気抵抗素子２ａ，２ｂを多チャ
ンネル化して配設した各種例を示したものである。同図
の（ａ）は、前記第１の実施例の構成を備えた磁気セン
サ装置を複数配列配置し、多チャンネル化したものであ
り、同図の（ｂ）は１個の筐体４内に複数の永久磁石１
を配列配置して多チャンネル化したものであり、同図の
（ｃ）は１個の筐体４内に１個の永久磁石１を収容固定
し、この１個の永久磁石１の磁極面に複数対の磁気抵抗
素子２ａ，２ｂを配列して多チャンネル化したものであ
る。FIG. 3 shows various examples in which the magnetoresistive elements 2a and 2b are arranged in multiple channels. FIG. 7A shows a case where a plurality of magnetic sensor devices having the configuration of the first embodiment are arranged and multi-channeled, and FIG. Multiple permanent magnets 1
Are arranged and multi-channeled. FIG. 3C shows a case where one permanent magnet 1 is housed and fixed in one housing 4, and the magnetic pole surface of the one permanent magnet 1 is A plurality of pairs of magnetoresistive elements 2a and 2b are arranged to form a multi-channel.
【００２８】この多チャンネル化した磁気センサ装置に
おいては、例えば図４に示すように、各チャンネルの磁
気情報の検出信号Ａ1 〜Ａ4 は、スイッチ群12のスイッ
チ切り替えにより、順次選択的に取り出され、所望の信
号処理が施されることとなる。各チャンネル信号をねり
出す手段は種々あるが、この実施例では、スイッチ群12
のスイッチ切り替えはスイッチ切り替え制御部13によっ
て行われており、このスイッチ切り替え制御部13からス
イッチ群12に各スイッチのオンオフ切り替えスキャン信
号が加えられ、このスイッチスキャン信号により、スイ
ッチ群12の各スイッチが自動的に切り替えられて各チャ
ンネルの磁気抵抗素子２ａ, ２ｂの磁気情報の検出信号
Ａ1 〜Ａ4 が取り出される。なお、この実施例におい
て、スイッチ群12とスイッチ切り替え制御部13によって
情報検出手段が構成されるが各スイッチに同期して素子
に印加する手段も容易に構成できる。In this multi-channel magnetic sensor device, for example, as shown in FIG. 4, the detection signals A 1 to A 4 of the magnetic information of each channel are sequentially and selectively extracted by switching the switch group 12. As a result, desired signal processing is performed. Although there are various means for projecting each channel signal, in this embodiment, the switch group 12
The switch switching of the switch group is performed by a switch switching control unit 13, and an on / off switching scan signal of each switch is added from the switch switching control unit 13 to the switch group 12, and each switch of the switch group 12 is switched by the switch scan signal. automatically switched to the magnetoresistive element 2a of each channel, the detection signal a 1 to a 4 of the magnetic information 2b is taken out. In this embodiment, the information detecting means is constituted by the switch group 12 and the switch switching control unit 13, but the means for applying the information to the element in synchronization with each switch can be easily constituted.
【００２９】この多チャンネル型の磁気センサ装置にお
いても、磁気検出面と各チャンネルの磁気抵抗素子２
ａ，２ｂ間に前記第１の実施例と同様に、磁界分離ヨー
ク11が配置されることで、各チャンネルにおける磁気抵
抗素子２ａ, ２ｂのクロストークを防止し、被検出体３
の磁気情報を高精度、かつ、高感度の下で検出すること
が可能となる。Also in this multi-channel type magnetic sensor device, the magnetic detection surface and the magnetoresistive element 2 of each channel are provided.
As in the first embodiment, the magnetic field separating yoke 11 is arranged between the a and 2b to prevent crosstalk between the magnetoresistive elements 2a and 2b in each channel.
Magnetic information can be detected with high accuracy and high sensitivity.
【００３０】なお、本発明は上記各実施例に限定される
ことはなく、様々な実施の態様を採り得る。例えば、上
記各実施例では感磁性素子を磁気抵抗素子（磁性薄膜磁
気抵抗素子を含む）によって構成したが、本発明の感磁
性素子は、ホール素子等の他の磁気検出素子を用いて構
成してもよい。It should be noted that the present invention is not limited to the above embodiments, and various embodiments can be adopted. For example, in each of the above embodiments, the magnetic sensitive element is constituted by a magnetoresistive element (including a magnetic thin film magnetoresistive element). However, the magnetic sensitive element of the present invention is constituted by using another magnetic detecting element such as a Hall element. You may.
【００３１】また、多チャンネルの磁気センサ装置を構
成する場合は、感磁性素子（磁気抵抗素子２ａ，２ｂ）
は、一次元状に配列配置してもよく、あるいは、二次元
のマトリックス状に配列配置したものでもよい。When a multi-channel magnetic sensor device is constructed, a magnetic sensitive element (magnetic resistance elements 2a, 2b)
May be arranged one-dimensionally, or may be arranged two-dimensionally in a matrix.
【００３２】さらに、図４の実施例では、信号取り出し
の出力端Ａ1 〜Ａ4 を切り替えたが、他の構成例として
は、出力端Ａ1 〜Ａ4 の信号取り込みに同期させて、電
源ラインから各チャンネルの感磁性素子（磁気抵抗素
子）に加える駆動電圧を切り替え供給するようにしても
よい。Further, in the embodiment shown in FIG. 4, the output terminals A 1 to A 4 for signal extraction are switched. However, as another configuration example, the power supply is synchronized with the signal reception at the output terminals A 1 to A 4. A drive voltage applied to the magnetic sensitive element (magnetic resistance element) of each channel may be switched and supplied from the line.
【００３３】[0033]
【発明の効果】本発明は、センサ検出面と感磁性素子間
であって、対を成す感磁性素子の境界部に磁界分離ヨー
クを設けた構成としたものであるから、バイアスマグネ
ットから対を成す一方の感磁性素子を通る磁界と他方の
感磁性素子を通る磁界とが磁界分離ヨークにより区分さ
れる結果、被検出体の磁気情報を検出する際、対を成す
一方側の感磁性素子と他方側の感磁性素子間のクロスト
ークを効果的に防止でき、被検出体の磁気情報を高精
度、かつ、高感度の下で検出することが可能となる。According to the present invention, since the magnetic field separating yoke is provided between the sensor detecting surface and the magnetic sensitive element and at the boundary between the paired magnetic sensitive elements, the pair is separated from the bias magnet. As a result of the magnetic field passing through one magnetic sensitive element and the magnetic field passing through the other magnetic sensitive element being separated by the magnetic field separating yoke, when detecting the magnetic information of the object to be detected, one magnetic sensitive element forming a pair Crosstalk between the other magnetic sensitive elements can be effectively prevented, and the magnetic information of the object to be detected can be detected with high accuracy and high sensitivity.
【００３４】また、前記の如く、対を成す一方側の感磁
性素子を通るバイアスマグネットの磁界と、他方側の感
磁性素子を通る磁界とが分離され、かつ、被検出体に向
かう磁界は分散形でなく真直状になるため、感磁性素子
と被検出体との間隙が大きくなっても、感磁性素子を通
る磁界は集中的に被検出体の磁気情報に注ぎ込まれるの
で、例えば、被検出体の磁気情報が対を成す一方側の感
磁性素子に対向する位置から他方の感磁性素子に対向す
る位置に移動する過程で、感磁性素子の一方側を通る磁
界と他方側を通る磁界との磁界強度がシャープに切り替
わり、被検出体の磁気情報を含む磁気回路のレラクタン
スの明確な変化により感磁性素子に印加される磁界変化
が極めて明確となり、これにより、磁気情報検出の分解
能を格段に高めることが可能となる。Further, as described above, the magnetic field of the bias magnet passing through the pair of magnetic sensitive elements on one side is separated from the magnetic field passing through the magnetic sensitive element on the other side, and the magnetic field directed to the object to be detected is dispersed. Because it is straight rather than shaped, even if the gap between the magnetic sensitive element and the object to be detected is large, the magnetic field passing through the magnetic element is intensively poured into the magnetic information of the object to be detected. In the process in which the magnetic information of the body moves from the position facing the magnetic sensing element on one side to the position facing the other magnetic sensing element, a magnetic field passing through one side of the magnetic sensing element and a magnetic field passing through the other side The magnetic field strength applied to the magnetic sensitive element becomes extremely clear due to the sharp change in the reluctance of the magnetic circuit containing the magnetic information of the object to be detected, and the resolution of the magnetic information detection is dramatically improved. Enhance Theft is possible.
【００３５】さらに、本発明では、磁界分離ヨークをセ
ンサ検出面の内部側、つまり、感磁性素子側に設けたも
のであるから、センサ検出面の外側を自由空間とするこ
とができ、したがって、この自由空間を被検出体の走行
空間とすることにより、この走行空間を走行する被検出
体の磁気情報の検出が可能となり、また、センサ検出面
を、例えば、ガスボンベ等の磁気情報が設置されている
タグに近接対向することにより、前記タグの磁気設置情
報を正確に読み取り検出することが可能となる。Further, in the present invention, since the magnetic field separating yoke is provided on the inner side of the sensor detection surface, that is, on the side of the magnetic sensitive element, the outside of the sensor detection surface can be made a free space. By setting the free space as the traveling space of the detected object, it becomes possible to detect magnetic information of the detected object traveling in the traveling space, and the sensor detection surface is provided with magnetic information such as a gas cylinder. The magnetic installation information of the tag can be accurately read and detected by facing the tag in close proximity.
【図１】本発明の第１の実施例を示す磁気センサ装置の
構成説明図である。FIG. 1 is a configuration explanatory view of a magnetic sensor device according to a first embodiment of the present invention.
【図２】同実施例の磁気センサ装置の磁気検出作用の説
明図である。FIG. 2 is an explanatory diagram of a magnetic detection operation of the magnetic sensor device of the embodiment.
【図３】本発明における多チャンネル型の磁気センサ装
置の各種構成例の説明図である。FIG. 3 is an explanatory diagram of various configuration examples of a multi-channel magnetic sensor device according to the present invention.
【図４】本実施例における多チャンネル型の磁気センサ
装置の磁気情報検出信号の取り込み例を示す回路説明図
である。FIG. 4 is a circuit diagram illustrating an example of capturing a magnetic information detection signal of the multi-channel magnetic sensor device according to the present embodiment.
【図５】本発明者が先に提案している磁気センサ装置の
説明図である。FIG. 5 is an explanatory diagram of a magnetic sensor device previously proposed by the present inventors.
【図６】図５に示した提案装置の動作状態の説明図であ
る。6 is an explanatory diagram of an operation state of the proposed device shown in FIG.
【図７】従来の一般的な磁気センサ装置の説明図であ
る。FIG. 7 is an explanatory view of a conventional general magnetic sensor device.
【図８】磁気抵抗素子の分圧回路の回路図である。FIG. 8 is a circuit diagram of a voltage dividing circuit of the magnetoresistive element.
１ 永久磁石 ２ａ，２ｂ 磁気抵抗素子 ３ 被検出体 ４ 筐体 11 磁界分離ヨーク 12 スイッチ群 13 スイッチ切り替え制御部 DESCRIPTION OF SYMBOLS 1 Permanent magnet 2a, 2b Magnetic resistance element 3 Detected object 4 Housing 11 Magnetic field separation yoke 12 Switch group 13 Switch switching control part
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平６−111251（ＪＰ，Ａ) 特開 昭63−317915（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) G11B 5/39 G01R 33/09 G06K 7/01 G07D 7/00 H01L 43/08 G01R 33/06 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-111251 (JP, A) JP-A-63-317915 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) G11B 5/39 G01R 33/09 G06K 7/01 G07D 7/00 H01L 43/08 G01R 33/06
Claims (3)
気バイアスされた分圧回路を形成する１対以上の感磁性
素子と、で構成され、該感磁性素子に対向する被検出体
によって変化する磁気バイアス変化量を検出する磁気セ
ンサにおいて、前記対をなす各感磁性素子の境界部と被
検出体間に該マグネットの磁束経路を区画する磁界分離
ヨークが設けられていることを特徴とする磁気センサ装
置。1. A magnetic bias change comprising a magnet and one or more pairs of magnetically sensitive elements forming a voltage dividing circuit magnetically biased by the magnet, wherein the magnetic bias change is caused by an object to be detected facing the magnetically sensitive element. A magnetic sensor device for detecting an amount, wherein a magnetic field separating yoke for partitioning a magnetic flux path of the magnet is provided between a boundary between the pair of magnetically sensitive elements and the object to be detected.
子対が複数配列配置され、この磁気情報を検出する各感
磁性素子対の検出信号を順次切り替えて取り出す情報検
出手段が設けられている請求項１記載の磁気センサ装
置。2. A plurality of magnetic sensing element pairs for detecting magnetic information of an object to be detected are arranged in a plurality, and information detecting means for sequentially extracting and extracting detection signals of each magnetic sensing element pair for detecting the magnetic information is provided. The magnetic sensor device according to claim 1.
されている請求項１又は請求項２記載の磁気センサ装
置。3. The magnetic sensor device according to claim 1, wherein the magnetic sensitive element is constituted by a magnetoresistive element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16994194A JP3291923B2 (en) | 1994-06-29 | 1994-06-29 | Magnetic sensor device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16994194A JP3291923B2 (en) | 1994-06-29 | 1994-06-29 | Magnetic sensor device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0817023A JPH0817023A (en) | 1996-01-19 |
| JP3291923B2 true JP3291923B2 (en) | 2002-06-17 |
Family
ID=15895744
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16994194A Expired - Fee Related JP3291923B2 (en) | 1994-06-29 | 1994-06-29 | Magnetic sensor device |
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| Country | Link |
|---|---|
| JP (1) | JP3291923B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4507585B2 (en) * | 2003-12-16 | 2010-07-21 | 日本電産サンキョー株式会社 | Drive circuit for paper sheet identification sensor and paper sheet identification device |
-
1994
- 1994-06-29 JP JP16994194A patent/JP3291923B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0817023A (en) | 1996-01-19 |
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