JPH06174471A - Electronic azimuth meter - Google Patents
Electronic azimuth meterInfo
- Publication number
- JPH06174471A JPH06174471A JP35215792A JP35215792A JPH06174471A JP H06174471 A JPH06174471 A JP H06174471A JP 35215792 A JP35215792 A JP 35215792A JP 35215792 A JP35215792 A JP 35215792A JP H06174471 A JPH06174471 A JP H06174471A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- bias magnetic
- bias
- azimuth
- field 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.)
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- Geophysics And Detection Of Objects (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、電子式方位計に係り、
特に地磁気を検出する素子が強磁性体からなり、そのヒ
ステリシス現象に基づく検出方位データの誤差が無視で
きないものとなる電子式方位計に好適なものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic compass,
In particular, it is suitable for an electronic azimuth meter in which the element for detecting the earth's magnetism is made of a ferromagnetic material and the error of the detected azimuth data based on the hysteresis phenomenon cannot be ignored.
【0002】[0002]
【従来の技術】従来、パーマロイ等の強磁性体で形成さ
れた磁気抵抗素子を利用する小型で携帯に便利な電子式
方位計が実用に供されている。2. Description of the Related Art Conventionally, a small-sized and portable electronic azimuth meter utilizing a magnetoresistive element formed of a ferromagnetic material such as permalloy has been put to practical use.
【0003】図3は、上記の如き電子式方位計の典型的
な回路構成を示したものである。磁気センサ部1は、図
示しないガラス等の基板上に形成された4個の磁気抵抗
素子MR1〜MR4およびこれらを接続してブリッジ回
路を形成する接続部K1〜K4からなり、上記磁気抵抗
素子MR1〜MR4はパーマロイ等の強磁性体を真空蒸
着することにより形成されており、また接続部K1〜K
4は通常の配線用材料を真空蒸着することにより形成さ
れている。そして、上記磁気抵抗素子MR1〜MR4
は、それぞれ相隣接する他の磁気抵抗素子との間で磁気
検出方向が直交するように配設されている。そして、接
続部K1とK3の間には電源Eにより直流電圧が印加さ
れており、接続部K2、K4の電位差は増幅回路3に与
えられるようになっている。また、磁気センサ部1に
は、互いに直交し、磁気抵抗素子MR1〜MR4の磁気
検出方向と45°をなす方向のバイアス磁界を発生する
バイアス磁界用コイルL1、L2が巻回されており、こ
れらには、それぞれ制御部2の制御の下で一定電流を供
給する電源Px、Pyが接線されている。なお、図2の
右上に示すようにバイアス磁界用コイルL1が発生する
バイアス磁界の方向をX軸方向とし、正の向きを同図の
右側の向きとし、バイアス磁界用コイルL2が発生する
バイアス磁界の方向をY軸方向とし、正の向きを同図の
上側の向きとする(すなわち、X軸、Y軸は磁気センサ
部1に固定されたものとなっている)。FIG. 3 shows a typical circuit configuration of the electronic azimuth meter as described above. The magnetic sensor unit 1 is composed of four magnetoresistive elements MR1 to MR4 formed on a substrate such as glass (not shown) and connecting portions K1 to K4 connecting these to form a bridge circuit. ~ MR4 is formed by vacuum-depositing a ferromagnetic material such as permalloy, and the connecting portions K1 to K
4 is formed by vacuum-depositing an ordinary wiring material. Then, the magnetoresistive elements MR1 to MR4.
Are arranged so that their magnetic detection directions are orthogonal to each other between the adjacent magnetoresistive elements. A direct-current voltage is applied between the connecting portions K1 and K3 by the power source E, and the potential difference between the connecting portions K2 and K4 is applied to the amplifier circuit 3. Further, the magnetic sensor unit 1 is wound with bias magnetic field coils L1 and L2 that are orthogonal to each other and generate a bias magnetic field in a direction forming 45 ° with the magnetic detection directions of the magnetoresistive elements MR1 to MR4. Power sources Px and Py for supplying a constant current under the control of the control unit 2 are tangentially connected to each other. Note that, as shown in the upper right of FIG. 2, the direction of the bias magnetic field generated by the bias magnetic field coil L1 is the X-axis direction, and the positive direction is the right direction in the figure, and the bias magnetic field generated by the bias magnetic field coil L2 is the same. Is the Y-axis direction and the positive direction is the upper direction in the figure (that is, the X-axis and the Y-axis are fixed to the magnetic sensor unit 1).
【0004】制御部2は、電源Px、Py、増幅回路3
等の各回路に制御信号を送り、それらを制御する回路で
ある。すなわち、制御部2は電源Px、Pyを交互に起
動せしめ、磁気センサ部1にX軸の正の向き又はY軸の
正の向きのバイアス磁界を交互に印加し、この両状態に
おける接続部K2、K4の電位差を処理すべく増幅回路
3、A/D変換回路4等に制御信号を送る回路である。
増幅回路3は、上記制御部2の制御の下に磁気センサ部
1の接続部K2、K4間の電位差を入力して、これを増
幅してA/D変換回路4に送出する回路である。A/D
変換回路4は制御部2の制御の下に増幅回路3の出力を
デジタル信号化して記憶部5に送出する回路である。ま
た、演算部6は、制御部2の制御の下に、記憶部5に記
憶されているデータ、すなわちバイアス磁界用コイルL
1によるバイアス磁界が印加されているときの接続部K
2、K4の電位差を増幅回路3で増幅し、A/D変換回
路4でデジタル化したデータ(地磁気のX軸方向成分に
対応するものとなっている)と、バイアス磁界用コイル
L2によるバイアス磁界が印加されているときの接続部
K2、K4の電位差を増幅回路3で増幅し、A/D変換
回路4でデジタル化したデータ(地磁気のY軸方向成分
に対応するものとなっている)とを取込んで方位(地磁
気の向きとY軸の正の向きとのなす角度)を算出する。The control unit 2 includes power supplies Px, Py and an amplifier circuit 3.
It is a circuit that sends a control signal to each circuit such as and controls them. That is, the control unit 2 alternately activates the power supplies Px and Py, alternately applies the bias magnetic field in the positive direction of the X axis or the positive direction of the Y axis to the magnetic sensor unit 1, and the connecting portion K2 in both states. , K4 is a circuit that sends a control signal to the amplifier circuit 3, the A / D conversion circuit 4 and the like in order to process the potential difference.
The amplifier circuit 3 is a circuit that inputs the potential difference between the connection portions K2 and K4 of the magnetic sensor unit 1 under the control of the control unit 2, amplifies the potential difference, and outputs the amplified potential difference to the A / D conversion circuit 4. A / D
The conversion circuit 4 is a circuit for converting the output of the amplification circuit 3 into a digital signal and sending it to the storage unit 5 under the control of the control unit 2. Under the control of the control unit 2, the calculation unit 6 also stores the data stored in the storage unit 5, that is, the bias magnetic field coil L.
Connection part K when a bias magnetic field of 1 is applied
2, the potential difference between K4 is amplified by the amplifier circuit 3 and is digitized by the A / D converter circuit 4 (corresponding to the X-axis direction component of the geomagnetism), and the bias magnetic field by the bias magnetic field coil L2. The potential difference between the connection portions K2 and K4 when the voltage is applied is amplified by the amplifier circuit 3 and digitized by the A / D converter circuit 4 (corresponding to the Y-axis direction component of the earth's magnetism). Then, the azimuth (the angle between the direction of the earth's magnetism and the positive direction of the Y axis) is calculated by taking in.
【0005】ところで、上記の如く、バイアス磁界用コ
イルL1、L2により、磁気抵抗素子MR1〜MR4に
バイアス磁界を印加しているのは以下の理由による。す
なわち、磁気抵抗素子の抵抗値は、図4に示すように印
加磁界の向きに拘らず印加磁界が強くなるほど低下する
(なお、同図では、縦軸を印加磁界の強さが0のときの
抵抗値で規格化した抵抗値すなわち規格化抵抗値として
いる)。このため、バイアス磁界を印加しないと、地磁
気の方向を判別できたとしてもその向き(北向き、南向
き)を判別できなくなるのである。また、印加磁界が弱
いと(地磁気レベルであると)同図に示すように抵抗の
変化が少なく測定誤差が大きくなるのである。そこで、
同図に示すように、印加磁界に対する抵抗の変化が最も
大きいところまでバイアス磁界を印加し、これに地磁気
を重畳して地磁気の向きにより抵抗値が変わるようにす
ると共に地磁気成分の僅かな変化でも大きな抵抗変化が
得られるようにしているのである。By the way, the reason why the bias magnetic field is applied to the magnetoresistive elements MR1 to MR4 by the bias magnetic field coils L1 and L2 as described above is as follows. That is, the resistance value of the magnetoresistive element decreases as the applied magnetic field becomes stronger irrespective of the direction of the applied magnetic field, as shown in FIG. The resistance value is standardized by the resistance value, that is, the standardized resistance value). Therefore, if the bias magnetic field is not applied, even if the direction of the geomagnetism can be discriminated, the direction (north facing or south facing) cannot be distinguished. Further, when the applied magnetic field is weak (at the geomagnetic level), the change in resistance is small and the measurement error is large as shown in FIG. Therefore,
As shown in the figure, a bias magnetic field is applied up to the point where the change in resistance to the applied magnetic field is the largest, and the geomagnetism is superimposed on this so that the resistance value changes depending on the direction of the geomagnetism, and even a slight change in the geomagnetic component It is designed so that a large resistance change can be obtained.
【0006】[0006]
【発明が解決しようとする課題】しかし、上記の如き電
子式方位計に利用される強磁性体の磁気抵抗素子には、
ヒステリシス現象があり、印加磁界の履歴によっては、
同一印加磁界の下でも異なった抵抗値を示す(図5参
照)。これに起因する計測方位の誤差は、比較的大き
く、無視できない。本発明は、上述の如き事情に鑑みて
なされたものであり、磁気抵抗素子のヒステリシス現象
に伴なう、計測方位の誤差を回避できる電子式方位計の
提供を目的とする。However, the ferromagnetic magnetoresistive element used in the electronic azimuth meter as described above has the following problems.
There is a hysteresis phenomenon, and depending on the history of the applied magnetic field,
Even under the same applied magnetic field, different resistance values are shown (see FIG. 5). The error in the measurement direction resulting from this is relatively large and cannot be ignored. The present invention has been made in view of the above circumstances, and an object thereof is to provide an electronic azimuth meter capable of avoiding an error in a measurement azimuth caused by a hysteresis phenomenon of a magnetoresistive element.
【0007】[0007]
【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、地磁気の検出にあたっては、磁気抵抗素
子の磁気的履歴を一定にすべく、先ず、磁気抵抗素子
に、一旦、定められた向きの大きな磁界を印加して、こ
れを磁気的に飽和させ、その後、当該磁界の印加を停止
して地磁気の検出を行なうようにした。SUMMARY OF THE INVENTION In order to achieve the above object, the present invention first determines the magnetic resistance of a magnetoresistive element in order to make the magnetic history of the magnetoresistive element constant when detecting geomagnetism. A large magnetic field in a given direction was applied to magnetically saturate the magnetic field, and then the magnetic field was stopped to detect the geomagnetism.
【0008】[0008]
【実施例】以下、図面に示す一実施例により、本発明を
具体的に説明する。図1は、本実施例の回路構成を示す
ものである。すなわちこの図1に示す回路構成は、概
ね、図3に示した従来例のものと同様になっているが
(なお、図1においては、図3における回路部と同一作
用、機能を持つ回路部については、図3における回路部
の符号と同一の符号を付している)、新たにコンデンサ
7と、充電用電源Ecと、制御部2の制御の下にオン・
オフ状態となり充電用電源Ecからコンデンサ7への充
電を断続するスイッチS1、S2と、制御部2の制御の
下にオン・オフ状態となりコンデンサ7の両極をバイア
ス磁界用コイルL1又はL2の両端に接続するスイッチ
S3、S4、S5とが追加されている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment shown in the drawings. FIG. 1 shows the circuit configuration of this embodiment. That is, the circuit configuration shown in FIG. 1 is substantially the same as that of the conventional example shown in FIG. 3 (note that in FIG. 1, a circuit unit having the same operation and function as the circuit unit in FIG. 3). 3 are attached with the same reference numerals as those of the circuit section in FIG. 3), a new capacitor 7, a charging power source Ec, and an on-state under the control of the control section 2.
Switches S1 and S2 which are in an off state and which intermittently charge the capacitor 7 from the charging power source Ec, and an on / off state which is under the control of the control unit 2 have both poles of the capacitor 7 at both ends of the bias magnetic field coil L1 or L2. Switches S3, S4 and S5 to be connected are added.
【0009】この様に構成された本実施例においては、
方位の計測に際し以下の如き動作が行なわれる。すなわ
ち、前記Y軸の正の向きを、方位を計測せんとする向き
に向けて、図示しないスイッチを操作したときは、先
ず、制御部2からスイッチS1、S2に制御信号が送ら
れて、これらのスイッチが図2に示す如くオン状態とな
り、充電用電源Ecによるコンデンサ7の充電が開始さ
れる。続いて、制御部2から電源Pxに制御信号が送ら
れて、図2に示す如くこの電源Pxからバイアス磁界用
コイルL1に電流が流されて磁気センサ部1にX軸の正
の向きに一定の強さのバイアス磁界が印加される(な
お、この場合、磁気センサ部1の個々の磁気抵抗素子に
印加される実際のバイアス磁界は、磁気抵抗素子の磁気
検出方向が上記X軸の方向から45°だけ傾いているの
で、バイアス磁界用コイルL1による上記バイアス磁界
を√2で除したものとなる)。In the present embodiment having such a configuration,
The following operations are performed when measuring the azimuth. That is, when the switch (not shown) is operated with the positive direction of the Y-axis directed toward the direction for measuring the azimuth, first, the control signal is sent from the control unit 2 to the switches S1 and S2, 2, the switch is turned on, and the charging of the capacitor 7 by the charging power source Ec is started. Subsequently, a control signal is sent from the control unit 2 to the power supply Px, and as shown in FIG. 2, a current is made to flow from the power supply Px to the bias magnetic field coil L1 so that the magnetic sensor unit 1 is fixed in the positive direction of the X axis. (In this case, the actual bias magnetic field applied to each magnetoresistive element of the magnetic sensor unit 1 is such that the magnetic detection direction of the magnetoresistive element is from the X-axis direction). Since it is inclined by 45 °, the bias magnetic field generated by the bias magnetic field coil L1 is divided by √2).
【0010】次いで、制御部2からスイッチS1、S2
に制御信号が送られて、これらのスイッチがオフ状態と
なり(図2参照)、上述の充電が停止し、更に制御部2
からスイッチS4、S5に制御信号が送られて、これら
のスイッチが図2に示すようにオン状態となり、これに
より既に十分充電されているコンデンサ7からバイアス
磁界用コイルL1に瞬間的に大きな電流が流れる。この
場合、バイアス磁界用コイルL1に流れる上記の大きな
電流は、電源Pxからバイアス磁界用コイルL1に流れ
ている電流と同一向きとなり、磁気センサ部1にはX軸
の正の向きの大きな磁界が印加され、各磁気抵抗素子
は、磁気的に飽和する(なお、この場合も、個々の磁気
抵抗素子に印加される磁界は上記磁界を√2で除したも
のになるが、これも極めて強い磁界となり、磁気抵抗素
子を磁気的に飽和状態にするのに十分な磁界となる)。Next, the control unit 2 switches the switches S1 and S2.
A control signal is sent to the switch, these switches are turned off (see FIG. 2), the above charging is stopped, and the control unit 2
2 sends a control signal to the switches S4 and S5 to turn them on, as shown in FIG. 2, whereby a large current is momentarily applied from the already fully charged capacitor 7 to the bias magnetic field coil L1. Flowing. In this case, the large current flowing in the bias magnetic field coil L1 has the same direction as the current flowing from the power supply Px to the bias magnetic field coil L1, and the magnetic sensor unit 1 receives a large magnetic field in the positive direction of the X axis. When applied, each magnetoresistive element is magnetically saturated (in this case also, the magnetic field applied to each magnetoresistive element is the above magnetic field divided by √2, but this is also an extremely strong magnetic field. And a magnetic field sufficient to magnetically saturate the magnetoresistive element).
【0011】然る後、スイッチS4、S5に制御部2か
ら制御信号が送られて、図2に示すように、これらのス
イッチがオフ状態となりコンデンサ7からの大電流の流
出は停止し、バイアス磁界用コイルL1には電源Pxか
らの電流だけが流れ、これにより、磁気抵抗素子MR1
〜MR4には通常のバイアス磁界と地磁気による磁界と
が印加される。そして、この時点において制御部2から
増幅回路3、A/D変換回路4等に制御信号t(図2参
照)が送られて接続部K2、K3の電位差が増幅回路3
に入力して増幅され、更にA/D変換回路4でデジタル
データ化され、これは地磁気のX軸方向成分に対応する
データとして記憶部5に記憶される。After that, a control signal is sent from the control unit 2 to the switches S4 and S5, and these switches are turned off, as shown in FIG. Only the current from the power source Px flows through the magnetic field coil L1, and this causes the magnetoresistive element MR1.
A normal bias magnetic field and a magnetic field due to geomagnetism are applied to MR4. Then, at this time point, the control signal t (see FIG. 2) is sent from the control unit 2 to the amplification circuit 3, the A / D conversion circuit 4 and the like, and the potential difference between the connection portions K2 and K3 changes.
Is input to and amplified by the A / D conversion circuit 4 and stored in the storage unit 5 as data corresponding to the X-axis direction component of the geomagnetism.
【0012】以上の如くして、地磁気のX軸方向成分に
対応するデータを記憶部5に記憶した後には、制御部2
からの制御信号により電源Pxからバイアス磁界用コイ
ルL1への電流の流出は停止され(図2参照)、X軸の
正の向きのバイアス磁界の印加も停止される。As described above, after the data corresponding to the X-axis direction component of the geomagnetism is stored in the storage unit 5, the control unit 2
The control signal from the power supply Px stops the outflow of current from the power supply Px to the bias magnetic field coil L1 (see FIG. 2), and also stops the application of the bias magnetic field in the positive direction of the X axis.
【0013】然る後、制御部2から、スイッチS1、S
2に制御信号が送られて、これらのスイッチがオン状態
となり(図2参照)、充電用電源Ecによるコンデンサ
7の充電が、再度、開始される。続いて、制御部2から
電源Pyに制御信号が送られて、図2に示す如く、この
電源Pyからバイアス磁界用コイルL2に電流が流され
て磁気センサ部1にY軸の正の向きに一定の強さのバイ
アス磁界が印加される(なお、この場合も、磁気センサ
部1の個々の磁気抵抗素子に印加される実際のバイアス
磁界は、前記同様にバイアス磁界用コイルL2による上
記バイアス磁界を√2で除したものとなる)。After that, the control unit 2 sends switches S1 and S
A control signal is sent to 2 to turn on these switches (see FIG. 2), and the charging of the capacitor 7 by the charging power source Ec is started again. Subsequently, a control signal is sent from the control unit 2 to the power supply Py, and as shown in FIG. 2, a current is made to flow from the power supply Py to the bias magnetic field coil L2 to cause the magnetic sensor unit 1 to move in the positive direction of the Y axis. A bias magnetic field having a constant strength is applied (in this case, the actual bias magnetic field applied to each magnetoresistive element of the magnetic sensor unit 1 is the same as described above by the bias magnetic field coil L2. Divided by √2).
【0014】次いで、制御部2からスイッチS1、S2
に制御信号が送られて、これらのスイッチがオフ状態と
なり(図2参照)、上述の充電が停止し、更に制御部2
からスイッチS3、S5に制御信号が送られて、これら
のスイッチが図2に示すようにオン状態となり、これに
より、既に十分に充電されているコンデンサ7からバイ
アス磁界用コイルL2に瞬間的に大きな電流が流れる。
この場合、バイアス磁界用コイルL2に流れる上記の大
きな電流は、電源Pyからバイアス磁界用コイルL2に
流れている電流と同一向きとなり磁気センサ部1にはY
軸の正の向きの大きな磁界が印加され、各磁気抵抗素子
は、磁気的に飽和する(なお、この場合も、個々の磁気
抵抗素子に実際に印加される磁界は、上記磁界を√2で
除したものになるが、それでも極めて強い磁界となり、
磁気抵抗素子は十分に磁気的に飽和する)。Next, the control unit 2 switches the switches S1 and S2.
A control signal is sent to the switch, these switches are turned off (see FIG. 2), the above charging is stopped, and the control unit 2
Sends a control signal to the switches S3 and S5, and these switches are turned on as shown in FIG. 2, so that the capacitor 7 which is already sufficiently charged momentarily becomes large in the bias magnetic field coil L2. An electric current flows.
In this case, the large current flowing through the bias magnetic field coil L2 is in the same direction as the current flowing from the power source Py into the bias magnetic field coil L2, and the magnetic sensor unit 1 has Y.
A large magnetic field in the positive direction of the axis is applied, and each magnetoresistive element is magnetically saturated (in this case, the magnetic field actually applied to each magnetoresistive element is the above magnetic field at √2). However, the magnetic field is still extremely strong,
Magnetoresistive elements are sufficiently magnetically saturated).
【0015】然る後、スイッチS3、S5に制御部2か
ら制御信号が送られて、図2に示すように、これらのス
イッチがオフ状態になり、コンデンサ7からバイアス磁
界用コイルL2への大電流の流出は停止し、バイアス磁
界用コイルL2には電源Pyからの電流だけが流れ、こ
れにより磁気抵抗素子MR1〜MR4には通常のバイア
ス磁界と地磁気による磁界とが印加される。そして、こ
の時点において制御部2から、増幅回路3、A/D変換
回路4等に再度、制御信号t(図2参照)が送られて接
続部K2、K3の電位差が増幅回路3で増幅され、更
に、A/D変換回路4でデジタルデータ化されて、これ
は、地磁気のY軸方向成分に対応するデータとして記憶
部5に記憶される。After that, a control signal is sent from the control unit 2 to the switches S3 and S5, these switches are turned off as shown in FIG. 2, and a large voltage is sent from the capacitor 7 to the bias magnetic field coil L2. The outflow of the current is stopped, and only the current from the power source Py flows in the bias magnetic field coil L2, whereby the normal bias magnetic field and the magnetic field due to the geomagnetism are applied to the magnetoresistive elements MR1 to MR4. Then, at this time, the control signal t (see FIG. 2) is sent again from the control unit 2 to the amplification circuit 3, the A / D conversion circuit 4, etc., and the potential difference between the connection portions K2, K3 is amplified by the amplification circuit 3. Further, it is converted into digital data by the A / D conversion circuit 4, and this is stored in the storage unit 5 as data corresponding to the Y-axis direction component of the geomagnetism.
【0016】以上の如くして、記憶部5に、地磁気のX
軸方向成分に対応するデータと地磁気のY軸方向成分に
対応するデータとが記憶された後には、演算部6は、上
記両データを取込み、これらのデータに基づいた演算を
実行して、上記Y軸が指す向きの方位を得るが、これ
は、制御部2により制御される図示しない表示部にデジ
タル表示されることになる。As described above, the storage unit 5 stores the geomagnetic X
After the data corresponding to the axial component and the data corresponding to the Y-axis component of the earth's magnetism are stored, the arithmetic unit 6 takes in both of the above-mentioned data, executes the arithmetic operation based on these data, and The azimuth of the direction pointed by the Y axis is obtained, which is digitally displayed on a display unit (not shown) controlled by the control unit 2.
【0017】以上の如く、本実施例では、地磁気のX軸
方向成分に係るデータを得るときは、その直前に、一
旦、上記X軸の正の向きに極めて強い磁界を印加し、磁
気抵抗素子MR1〜MR4を磁気的に飽和せしめ、その
後、この強い磁界の印加を停止した上で上記データを得
て、他方、地磁気のY軸方向成分に係るデータを得ると
きは、その直前に、一旦、上記Y軸の正の向きに極めて
強い磁界を印加し、磁気抵抗素子MR1〜MR4を磁気
的に飽和せしめ、その後、この強い磁界の印加を停止し
た上で、上記データを得るようにしたので、X軸又はY
軸方向成分に係るデータを得るときは、磁気抵抗素子M
R1〜MR4の磁気的履歴が一定になっていることにな
り、履歴の違いによる計測方位データの誤差を回避でき
ることになる。As described above, in the present embodiment, when data relating to the X-axis direction component of the earth's magnetism is obtained, immediately before that, an extremely strong magnetic field is applied once in the positive direction of the X-axis, and the magnetoresistive element. When MR1 to MR4 are magnetically saturated and then the application of this strong magnetic field is stopped to obtain the above-mentioned data, while the data relating to the Y-axis direction component of the geomagnetism is obtained, immediately before that, Since an extremely strong magnetic field is applied in the positive direction of the Y-axis to magnetically saturate the magnetoresistive elements MR1 to MR4, and then the application of the strong magnetic field is stopped, the above data is obtained. X axis or Y
When obtaining data relating to the axial component, the magnetoresistive element M
Since the magnetic histories of R1 to MR4 are constant, it is possible to avoid the error of the measurement direction data due to the difference of the histories.
【0018】[0018]
【発明の効果】本発明は、以上詳述したように、地磁気
の検出にあたっては、磁気抵抗素子の磁気的履歴を一定
にすべく、先ず、磁気抵抗素子に、一旦、定められた向
きの大きな磁界を印加して、これを地磁気に飽和させ、
その後、当該磁界の印加を停止して地磁気の検出を行な
うようにした電子式方位計に係るものであるから、磁気
抵抗素子のヒステリシス現象に伴なう、計測方位の誤差
を回避できる電子式方位計の提供を可能とする。As described above in detail, according to the present invention, in detecting the geomagnetism, in order to make the magnetic history of the magnetoresistive element constant, first, the magnetoresistive element is temporarily moved in a predetermined direction. Apply a magnetic field to saturate it with geomagnetism,
After that, since it relates to the electronic azimuth meter which stops the application of the magnetic field and detects the geomagnetism, the electronic azimuth that can avoid the error in the measurement azimuth associated with the hysteresis phenomenon of the magnetoresistive element. It is possible to provide the total.
【図1】本発明の一実施例の回路構成を示す図である。FIG. 1 is a diagram showing a circuit configuration of an embodiment of the present invention.
【図2】上記図1に示すスイッチのオン・オフ等を示す
タイムチャートである。FIG. 2 is a time chart showing ON / OFF of the switches shown in FIG.
【図3】従来例の回路構成を示す図である。FIG. 3 is a diagram showing a circuit configuration of a conventional example.
【図4】磁気抵抗素子の特性を示す図である。FIG. 4 is a diagram showing characteristics of a magnetoresistive element.
【図5】磁気抵抗素子におけるヒステリシス現象を説明
するための図である。FIG. 5 is a diagram for explaining a hysteresis phenomenon in a magnetoresistive element.
1 磁気センサ部 2 制御部 7 コンデンサ MR1〜MR4 磁気抵抗素子 L1、L2 バイアス磁界用コイル Px、Py、E 電源 Ec 充電用電源 DESCRIPTION OF SYMBOLS 1 Magnetic sensor part 2 Control part 7 Capacitor MR1-MR4 Magnetoresistive element L1, L2 Bias magnetic field coil Px, Py, E power supply Ec Charging power supply
Claims (2)
ス磁界発生手段と、 このバイアス磁界発生手段により複数の方向のバイアス
磁界が印加された時の前記磁気検出手段の出力から方位
を算出する方位算出手段と、 前記磁気検出手段を磁気飽和させる磁気飽和手段とを備
えることを特徴とする電子式方位計。1. A magnetic detection means, a bias magnetic field generation means for applying a plurality of bias magnetic fields in different directions, and a magnetic field detection means for applying a bias magnetic field in a plurality of directions by the bias magnetic field generation means. An electronic azimuth meter comprising: an azimuth calculation means for calculating an azimuth from an output; and a magnetic saturation means for magnetically saturating the magnetic detection means.
互に直交する状態でブリッジ状に結合された4個の磁気
抵抗素子と、 互に直交する状態で前記磁気抵抗素子に巻回された少な
くとも2個のバイアス磁界用コイルと、 前記4つの磁気抵抗素子の結合部のうち相対向する2つ
の結合部間に定電圧を印加する電圧印加手段と、 前記2個のバイアス磁界用コイルに交互にバイアス磁界
を発生させるための第1のバイアス磁界用コイル駆動手
段と、 この第1のバイアス磁界用コイル駆動手段で前記バイア
ス磁界用コイルにバイアス磁界が発生されている時の前
記4つの磁気抵抗素子の結合部のうち前記定電圧が印加
されている2つの結合部以外の2つの相対向する結合部
間の電位差を検出する検出手段と、 この検出手段が検出した2つの電位差から方位を算出す
る演算手段と、 前記バイアス磁界用コイルに前記磁気抵抗素子が磁気飽
和を起こす磁界を発生させるための第2のバイアス磁界
用コイル駆動手段とを備えることを特徴とする電子式方
位計。2. Four magnetoresistive elements that are coupled in a bridge shape so that the magnetic detection directions of adjacent magnetoresistive elements are orthogonal to each other, and are wound around the magnetoresistive elements in a mutually orthogonal state. At least two bias magnetic field coils, voltage applying means for applying a constant voltage between two opposing coupling parts of the four magnetoresistive element coupling parts, and the two bias magnetic field coils alternately. First bias magnetic field coil driving means for generating a bias magnetic field in the magnetic field, and the four magnetic resistances when a bias magnetic field is generated in the bias magnetic field coil by the first bias magnetic field coil driving means. Detecting means for detecting a potential difference between two opposing coupling portions other than the two coupling portions to which the constant voltage is applied among the coupling portions of the element, and two potential differences detected by the detecting means. An electronic azimuth, comprising: an arithmetic means for calculating the azimuth from the second bias magnetic field coil; and a second bias magnetic field coil driving means for causing the bias magnetic field coil to generate a magnetic field in which the magnetoresistive element causes magnetic saturation. Total.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP35215792A JPH06174471A (en) | 1992-12-10 | 1992-12-10 | Electronic azimuth meter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP35215792A JPH06174471A (en) | 1992-12-10 | 1992-12-10 | Electronic azimuth meter |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH06174471A true JPH06174471A (en) | 1994-06-24 |
Family
ID=18422172
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP35215792A Pending JPH06174471A (en) | 1992-12-10 | 1992-12-10 | Electronic azimuth meter |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH06174471A (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002095330A1 (en) * | 2001-05-22 | 2002-11-28 | Hitachi Metals, Ltd. | Azimuth meter |
WO2006101050A1 (en) * | 2005-03-24 | 2006-09-28 | Alps Electric Co., Ltd. | Magnetic field detecting apparatus and electronic compass using the same |
KR100800279B1 (en) * | 2004-07-14 | 2008-02-05 | 히타치 긴조쿠 가부시키가이샤 | Azimuth meter having spin-valve giant magneto-resistive elements |
US7868613B2 (en) | 2006-10-31 | 2011-01-11 | Tdk Corporation | Magnetic sensor and manufacturing method thereof |
US7969149B2 (en) | 2007-02-27 | 2011-06-28 | Tdk Corporation | Magnetic sensor, magnetic direction sensor, method of detecting magnetic field and method of detecting magnetic direction |
WO2014111976A1 (en) * | 2013-01-18 | 2014-07-24 | 株式会社村田製作所 | Magnetic sensor and production method therefor |
-
1992
- 1992-12-10 JP JP35215792A patent/JPH06174471A/en active Pending
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002095330A1 (en) * | 2001-05-22 | 2002-11-28 | Hitachi Metals, Ltd. | Azimuth meter |
US6826842B2 (en) | 2001-05-22 | 2004-12-07 | Hitachi Metals, Ltd. | Azimuth meter |
KR100846078B1 (en) * | 2001-05-22 | 2008-07-14 | 히타치 긴조쿠 가부시키가이샤 | Azimuth meter |
KR100800279B1 (en) * | 2004-07-14 | 2008-02-05 | 히타치 긴조쿠 가부시키가이샤 | Azimuth meter having spin-valve giant magneto-resistive elements |
WO2006101050A1 (en) * | 2005-03-24 | 2006-09-28 | Alps Electric Co., Ltd. | Magnetic field detecting apparatus and electronic compass using the same |
KR100852268B1 (en) * | 2005-03-24 | 2008-08-14 | 알프스 덴키 가부시키가이샤 | Magnetic field detecting apparatus and electronic compass using the same |
US7868613B2 (en) | 2006-10-31 | 2011-01-11 | Tdk Corporation | Magnetic sensor and manufacturing method thereof |
US7969149B2 (en) | 2007-02-27 | 2011-06-28 | Tdk Corporation | Magnetic sensor, magnetic direction sensor, method of detecting magnetic field and method of detecting magnetic direction |
WO2014111976A1 (en) * | 2013-01-18 | 2014-07-24 | 株式会社村田製作所 | Magnetic sensor and production method therefor |
CN104919328A (en) * | 2013-01-18 | 2015-09-16 | 株式会社村田制作所 | Magnetic sensor and production method therefor |
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