JPS587891A - Magnetic sensor device - Google Patents

Abstract

PURPOSE:To improve the magnetic sensitivity by driving a magnetoelectric transducer made of an IbSb semiconductor material at a temperature lower than the ambient temperature by using Peltier effect semiconductor means. CONSTITUTION:Magnetoelectric transducers 6, 7 made of indium antimony (InSb) semiconductor material are bonded to a base 4 made of a magnetic material, a heat transfer block 5 is formed around the base, an electronic cooler 10 for cooling the block 5 and the base 4 to the prescribed temperature lower than the ambient temperature by means of Peltier effect semiconductor is prepared, and is contained in a constant-temperature housing 1. The cooler 10 cools metallic plate 8, and a heat radiating plate 9 is reversely heated. Accordingly, heat is radiated from a radiator 11, and the cooled plate 8 is operated to cool at the temperature lower than the ambient temperature a permanent magnet 4, the block 5 and the transducers 6, 7, which are thus operated at the lower tempature, thereby largely improving the output sensitivity of the base 4.

Description

【発明の詳細な説明】 本発明はＩｎ８ｔ：を用いた磁気センサ装置に関する。[Detailed description of the invention] The present invention relates to a magnetic sensor device using In8t:.

金属間化合物半導体であるインジウムアンチモン（Ｉｎ
８ｂ　）で作った磁電変換素子は、磁界の存在下で、磁
気感度が温度の影響な大きく受ける特徴を示す。即ち、
常温より高温側では磁気感度が次第に小さくなり、逆に
常温より低温側では磁気感度が次第に大きくなる。Indium antimony (In
The magnetoelectric transducer fabricated in 8b) exhibits the characteristic that its magnetic sensitivity is greatly influenced by temperature in the presence of a magnetic field. That is,
Magnetic sensitivity gradually decreases at temperatures higher than room temperature, and conversely, magnetic sensitivity gradually increases at temperatures lower than room temperature.

通常、此の様な磁電変換素子は、常温を中心とした所定
の温度範囲で使用されるので、磁気感度の改善は素子形
状に重点が置かれて来た。Generally, such magnetoelectric transducers are used in a predetermined temperature range centered around room temperature, and therefore, emphasis has been placed on the shape of the element in order to improve magnetic sensitivity.

所で、上述の様に、磁電変換素子は、低温度の領域で高
い磁気感度を示す。此の事に鑑み、永久磁石の磁極表面
にＩｎ８ｂ磁気抵抗素子を貼着して構成した磁気センサ
を液体窒素を入れた容器の中に封管する実験が行われた
。しかし、此の方法では、素子の磁気感度を改善する事
は出来るが、実用的見地からは液体窒素中に磁気センサ
を封管する技術が難しく、磁気七ンづとして高価になる
と共に、絶対零度に近い為永久磁石の特性に変化を生ず
る場合がある等の問題がある事がわかった。By the way, as mentioned above, the magnetoelectric transducer exhibits high magnetic sensitivity in a low temperature region. In view of this, an experiment was conducted in which a magnetic sensor constructed by pasting an In8b magnetoresistive element on the magnetic pole surface of a permanent magnet was sealed in a container containing liquid nitrogen. However, although this method can improve the magnetic sensitivity of the element, from a practical standpoint, the technology of sealing the magnetic sensor in liquid nitrogen is difficult, the magnetic tube is expensive, and the temperature is low at absolute zero. It was found that there are problems such as changes in the characteristics of the permanent magnet because it is close to .

本発明は常温より低い温度で磁電変換素子を駆動して磁
気感度を改善すると共に実用に供する磁気センサ装置を
提供するものである。The present invention provides a magnetic sensor device that improves magnetic sensitivity by driving a magnetoelectric transducer at a temperature lower than room temperature and that can be put to practical use.

以下添付図面を用いて本発明の実施例を詳細に説明する
。第１図に於て、筐体１は一端が開放され反対端には開
孔２が設けられ、比較的断熱効果のある樹脂、例えば、
エボキン樹脂、シリコン樹脂等で輪形に成型される。筺
体１の開孔２の部分は、筐体１の外表面に沿ってガラス
板やアスベスト板等の断熱板３で密封される。筐体１の
内部には、永久磁石４を其の磁極（Ｎ極）を開孔２に向
けて配置し、磁石４の回りには非磁性で且熱伝導性の良
い金属で作った伝熱ブロック５・例えばアル１ニウムや
銅を配設する。Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1, a housing 1 is open at one end and has an opening 2 at the opposite end, and is made of a resin having a relatively heat insulating effect, for example.
It is molded into a ring shape using Evokin resin, silicone resin, etc. The opening 2 of the housing 1 is sealed along the outer surface of the housing 1 with a heat insulating plate 3 such as a glass plate or an asbestos plate. Inside the housing 1, a permanent magnet 4 is arranged with its magnetic pole (N pole) facing the opening 2, and around the magnet 4 is a heat transfer magnet made of a non-magnetic and highly thermally conductive metal. Block 5: Place aluminum or copper, for example.

永久磁石４の開孔２側の磁極表面には、Ｌｎ８ｂを使用
して作られた一対の磁気抵抗素子６，７が並列に貼着さ
れている。此等の素子６，７は、従来同権直列に接続さ
れて制御電流、例えば直流電流が流され、画素子６と７
の間から出力電圧を取出す方法で使用される。此は素子
６．７が３端子の素子として作られても同様である。A pair of magnetoresistive elements 6 and 7 made of Ln8b are attached in parallel to the magnetic pole surface of the permanent magnet 4 on the aperture 2 side. Conventionally, these elements 6 and 7 are connected in series with the same power, and a control current, for example, a direct current, is passed through the pixels 6 and 7.
It is used in a method to extract the output voltage from between. The same applies even if the elements 6 and 7 are made as three-terminal elements.

永久磁石４の他方の磁極（Ｓ極）側には、硼性体で且熱
伝導性の良い金属板８、例えば軟鉄の板が、磁石４や伝
熱ブロック５と熱伝導良く密着している。On the other magnetic pole (S pole) side of the permanent magnet 4, a metal plate 8 made of boron and having good thermal conductivity, such as a soft iron plate, is in close contact with the magnet 4 and the heat transfer block 5 with good heat conduction. .

筐体１の開放端は、熱的電気的伝導が良い金属、例えば
アルミニウムや銅等から作られた放熱板９で密封される
。此の放熱板９と磁性金属板８の間には、ペルチェ効果
を有する半導体を用いた電子冷却部１０が配設されてい
る。ベルチェ効果半導体トシテハ、ＢｉｔＴｏ、、８ｂ
ｔＴｅｓ、Ｂ１．ａ＠ｓ。The open end of the housing 1 is sealed with a heat sink 9 made of a metal with good thermal and electrical conductivity, such as aluminum or copper. Between the heat dissipation plate 9 and the magnetic metal plate 8, an electronic cooling unit 10 using a semiconductor having a Peltier effect is disposed. Beltier effect semiconductor, BitTo, 8b
tTes, B1. a@s.

Ｂ　ｉ　＊　Ｔ　６　ｓ　　８　ｂ　ｔ　Ｔ　８　ｍ、
　Ｂ　ｉ　＊　Ｔ　＠　＠　−８ｂ　＊　８　ｓ　１等
電子冷却素子として使用される半導体材料の中から選ば
れる。B i * T 6 s 8 b t T 8 m,
B i * T @ -8b * 8 s 1 is selected from semiconductor materials used as electronic cooling elements.

電子冷却部１０は、図示しないリード線を介して低電圧
直流電源に接続される。そして、電流を流した時、金属
板８側が冷却され、放熱板９側が発熱となる様に構成さ
れている。The electronic cooling unit 10 is connected to a low voltage DC power source via a lead wire (not shown). The structure is such that when a current is applied, the metal plate 8 side is cooled and the heat sink 9 side generates heat.

尚、上記構成は、被検出体、例えば磁性片、磁性インキ
等を用いた印刷物、磁石片等が断熱板６に接触しない場
合の例であるが、接触移動する場合は非磁性金属板、例
えばタングステン板や燐青銅板塾で補強する。又、筐体
１の断熱効果が低い場合には、コルク、アスベスＦ１ウ
レタンホーム、シリカ等の断熱材で所定の厚さの内張を
施す。更に又、磁性板８と電子冷却部１０の間を電気的
に絶縁する必要がある場合には、熱伝導の良いセラミッ
クやマイカ等を介在させる。The above configuration is an example in which the object to be detected, such as a magnetic piece, a printed matter using magnetic ink, a magnet piece, etc., does not come into contact with the heat insulating plate 6; Reinforce with tungsten plate or phosphor bronze plate. If the heat insulating effect of the casing 1 is low, it is lined with a predetermined thickness of a heat insulating material such as cork, asbeth F1 urethane foam, or silica. Furthermore, if it is necessary to electrically insulate between the magnetic plate 8 and the electronic cooling unit 10, ceramic, mica, or the like having good thermal conductivity is interposed.

本発明装置の動作について説明する。The operation of the device of the present invention will be explained.

磁気センサ装置は、被検出体に対し、被検出体の移動に
伴って磁気抵抗素子６と７を通る磁束の磁束密度が交互
に変化する様に配置される。従って、被検出体が移動す
れば、磁気抵抗素子６と７は交互に其の内部抵抗値を変
化させ、図示しない画素子の間から引出した出力電圧端
子の電圧を変化させる。此の電圧変化は、被検出体の移
動信号として既知の回路で処理される。The magnetic sensor device is arranged with respect to the object to be detected so that the magnetic flux density of the magnetic flux passing through the magnetoresistive elements 6 and 7 changes alternately as the object moves. Therefore, when the object to be detected moves, the magnetoresistive elements 6 and 7 alternately change their internal resistance values, thereby changing the voltage at the output voltage terminal drawn out from between the pixel elements (not shown). This voltage change is processed by a known circuit as a movement signal of the detected object.

一方、ペルチェ効果半導体を用いた電子冷却部１０には
、直流電・流が流され、金属板８゛が冷却され、逆に放
熱板９が発熱される。放熱板９の熱は、山形に形成した
放熱部１１から大気中に放熱される。放熱を促進する為
に空冷扇風機等を併設或は併用しても良い。On the other hand, a direct current is passed through the electronic cooling unit 10 using a Peltier effect semiconductor, thereby cooling the metal plate 8' and, conversely, generating heat from the heat dissipation plate 9. The heat from the heat radiating plate 9 is radiated into the atmosphere from the heat radiating portion 11 formed in a chevron shape. In order to promote heat dissipation, an air-cooling fan or the like may be installed or used in combination.

冷却された金属板８は、永久磁石４及び伝熱ブロック５
を次々と冷却し、結果的に磁気抵抗素子６．７が冷却さ
れる。伝熱ブロック５は、磁気抵抗素子６．７の冷却を
促進し且冷却温度を維持する為のものである。磁気抵抗
素子６．７の冷却温度は、磁気センサ装置の回りの大気
温度及び大りに対する磁気センサ装置の断熱の程度に依
って左右されるが、動作の基準となる温度はペルチェ効
果半導体に流す電流の電流値を調整する事により常温（
２５℃）より低い温度に定められる。而して、磁気抵抗
素子６．７は、基準温度を中心に使用時の大気温度に影
響された温度で動作する事になる。The cooled metal plate 8 is connected to the permanent magnet 4 and the heat transfer block 5.
are successively cooled, and as a result, the magnetoresistive element 6.7 is cooled down. The heat transfer block 5 is for promoting cooling of the magnetoresistive element 6.7 and maintaining the cooling temperature. The cooling temperature of the magnetoresistive element 6.7 depends on the atmospheric temperature around the magnetic sensor device and the degree of insulation of the magnetic sensor device against large forces, but the temperature that serves as the reference for operation is the temperature that is passed through the Peltier effect semiconductor. By adjusting the current value of the current, the temperature at room temperature (
25°C). Thus, the magnetoresistive elements 6.7 operate at a temperature influenced by the atmospheric temperature during use, with the reference temperature being the center.

磁気抵抗素子６，７が冷却されて常温より低い温度、例
えば０℃とか零下１０”Ｃに其の基準温度が定められる
と、上述した如く、磁気抵抗素子６７は磁界の影響下に
於ける抵抗変化率の大きい位置で動作するから、其の出
力感度は大幅に改善される。When the magnetoresistive elements 6 and 7 are cooled and their reference temperature is set to a temperature lower than room temperature, for example 0°C or minus 10"C, the magnetoresistive element 67 changes its resistance under the influence of the magnetic field, as described above. Since it operates at a position where the rate of change is large, its output sensitivity is greatly improved.

又、−気抵抗素子６と７を通る磁束の磁束密度が等しい
場合、其の出力電圧（中性点電圧）は大気温度が変化し
ても不変である事が要求される。Further, when the magnetic flux densities of the magnetic fluxes passing through the negative resistance elements 6 and 7 are equal, the output voltage (neutral point voltage) is required to remain unchanged even if the atmospheric temperature changes.

しかし、同じウェハから注童深く作った２つの磁気抵抗
素子を使用しても、大気温度の常温より高い高温領域で
其の温度係数に差が生じ、中性点電圧が大気温度を変数
として変動する所磨申性点ド昇に帰因して格子振動によ
る熱擾乱を生じる為と考えられている。此に射しても本
発明は有効に作用し、基準温度を０℃以下に設定すれば
、中性点ドリフトは殆ど生じなくなる。However, even if two magnetoresistive elements made from the same wafer are used, their temperature coefficients will differ in the high temperature range above normal atmospheric temperature, and the neutral point voltage will fluctuate with atmospheric temperature as a variable. This is thought to be due to the thermal disturbance caused by lattice vibration due to the mechanical point de-ascent. The present invention works effectively even in this case, and if the reference temperature is set to 0° C. or lower, neutral point drift will hardly occur.

実験例を述べると、２５℃の大気濃度に於て、’　２．
２　Ｋガウスの磁界中で２つの磁気抵抗素子は其抗素子
を直列にｔＩ！続して５■の直流電麺にＩ！！続しな磁
気センサ装置のペルチェ効果半導体片に６Ｖで１００ｍ
Ａの直流電流を流し磁気抵抗素子を０℃に冷却した処、
抵抗値は其れ其れ１７９にΩとなり、磁気抵抗直線感度
Ｋ（％）は２５℃の時の１２２９倍に、又抵抗変化率△
Ｒ（＆）は２５℃の時の１．６４０倍になった。此の結
果磁気抵抗索子に２５℃の時流りた電流と同じ電流値の
電流を流すと出力感度は２５℃の時の２．０２倍になる
。To describe an experimental example, at an atmospheric concentration of 25°C, '2.
Two magnetoresistive elements are connected in series with each other in a magnetic field of 2 K Gauss at tI! Next, I went to 5■ DC Denmen! ! 100m at 6V to a Peltier effect semiconductor piece of a continuous magnetic sensor device
When a direct current of A is applied and the magnetoresistive element is cooled to 0°C,
The resistance value is 179Ω, the magnetic resistance linear sensitivity K (%) is 1229 times that at 25°C, and the resistance change rate is △
R(&) was 1.640 times that at 25°C. As a result, if a current with the same current value as the current flowing at 25°C is passed through the magnetoresistive cable, the output sensitivity will be 2.02 times that at 25°C.

第２図は第１図の電子冷却部の構成を示す。伝熱良好な
電気的絶縁材、例えばガラス、マイカ等から作られた板
１５．１４の間に、銅板で作られた電極１５，１６．１
７，１８．１９を介して４Ｅに対し図示の如く麹続した
時、絶縁板１３が発熱側になり、絶縁板１４が冷却側に
なる様に、半導体片２０．２２は１３１１！、又半導体
片２１．２３はＮｌｌを使用する。半導体片の数は、冷
却温度及び電源条件に依って増減出来る事は言うまでも
ない。FIG. 2 shows the configuration of the electronic cooling section of FIG. 1. Electrodes 15, 16.1 made of copper plates are placed between plates 15.14 made of an electrically insulating material with good heat transfer, such as glass, mica, etc.
7, 18, and 19 to 4E as shown in the figure, the semiconductor pieces 20.22 are 1311! so that the insulating plate 13 becomes the heat generating side and the insulating plate 14 becomes the cooling side. , and the semiconductor pieces 21 and 23 use Nll. It goes without saying that the number of semiconductor pieces can be increased or decreased depending on the cooling temperature and power supply conditions.

上記実施例では、永久磁石４の上にＩｎ８ｂ磁気抵抗素
子６，７を貼着した例について説明したが、此に限定さ
れるものではない。被検出体が発磁作用を有する場合に
は、Ｉｌ！１ＷＪの磁石４を磁性体に代える事が出来る
。又、磁石４を磁性体とした時は、磁気抵抗素子６．７
をＬｎ８ｂホール素子に代えて磁気センサ装置を構成す
る事が出来る。此の場合は、１１１図の装置と用達は相
違し、磁界の存在検知とか磁界強度の検出の為に使用さ
れるが、磁気感度が向上する為に微弱な磁界にも反応す
る。In the above embodiment, an example was described in which the In8b magnetoresistive elements 6 and 7 were stuck on the permanent magnet 4, but the present invention is not limited to this. When the object to be detected has a magnetizing effect, Il! The 1WJ magnet 4 can be replaced with a magnetic material. In addition, when the magnet 4 is made of a magnetic material, the magnetic resistance element 6.7
A magnetic sensor device can be constructed by replacing the Ln8b Hall element with the Ln8b Hall element. In this case, the purpose is different from that of the device shown in FIG. 111, and it is used to detect the presence of a magnetic field or the strength of a magnetic field, but because the magnetic sensitivity is improved, it responds even to weak magnetic fields.

本発明の磁気セン賃装置は、上述の様に、磁電変換素子
を負の温度係数を持つインジウム・アンチモン（Ｉｎ８
ｂ）で作り、此の素子をペルチェ効果牛専体を用いた冷
却手段で常温より低い温度迄其の動作の基準となる温度
を下げて駆動するものであるから、磁気センサ装置の出
力感度が大幅に改善され、大気温度の変化があっても大
きな出力が得られる外、微弱な磁界の変化も精度良く検
出出来る利点がある。As described above, the magnetic sensor device of the present invention uses indium antimony (In8), which has a negative temperature coefficient, as a magnetoelectric conversion element.
b), and this element is driven by lowering the reference temperature of its operation to a temperature lower than room temperature using a cooling means exclusively using Peltier effect, so the output sensitivity of the magnetic sensor device is This has been greatly improved, and has the advantage of not only providing a large output even when there are changes in atmospheric temperature, but also being able to accurately detect changes in weak magnetic fields.

又、出力電圧に於ける中性点温度ドリフトが除去される
か或は殆どなくなるので、微小な出力であっても８／Ｎ
を大きくシ、使用機器を正確に動作させる事が出来る。In addition, the neutral point temperature drift in the output voltage is eliminated or almost eliminated, so even if the output is small, the 8/N
This allows the equipment to operate more accurately.

更に、液体窒素等の冷却体を使用しない為、過度の冷却
もなく、又封管技術も使用としないので、実用的且安価
に作れる利点がある。Furthermore, since a cooling medium such as liquid nitrogen is not used, there is no excessive cooling, and no sealing tube technology is used, so there is an advantage that it can be manufactured practically and at low cost.

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

第１図は本発明磁気センサ装置の概略構成断面図、第２
図は第１図の装置に使用の電子冷却手段の一例を示す構
成図である。 図中の１は筐体、４．は磁石、５は金属プマツク、６．
７は磁電変換素子、８は磁性金属板、９は放熱板、１０
は電子冷却部である。 特許出願人 電気音響株式会社FIG. 1 is a schematic cross-sectional view of the magnetic sensor device of the present invention, and FIG.
This figure is a block diagram showing an example of an electronic cooling means used in the apparatus of FIG. 1. 1 in the figure is the housing, 4. is a magnet, 5 is a metal mask, 6.
7 is a magnetoelectric conversion element, 8 is a magnetic metal plate, 9 is a heat sink, 10
is the electronic cooling section. Patent applicant Electric Acoustic Co., Ltd.

Claims (1)

【特許請求の範囲】 ｔインジウム・アンチモン半導体材料から作った磁電変
換素子を、ペルチェ効果半導体手段を用いて常温より低
い温度迄冷却しつつ駆動する如く構成した事を特徴とす
る磁気センサ装置。 ２、インジウム・アンチモン半導体材料から作った磁電
変換素子を磁性材料からなる基台に貼着し、該基台の回
りに伝熱ブロックを設け、ペルチェ効果半導体を用いて
前記ブロックと前記基台を常温より低い所定の温度迄冷
却する電子冷却部を備え、上記各構成要素を放熱部分を
除いて保温筐体内に収容する如く構成し、前記半導体に
直流電源から調整可能な直流電流を流し、前記磁電変換
素子の出力感度を向上する構成を特徴とする磁気センサ
装置。 ３、前記基台は着磁され、前記磁電変換素子は磁気抵抗
素子として構成され、該素子は前記着磁された基台の一
方の磁極面に貼着される様構成した特許請求の範囲第２
項記載の磁気センサ装置。[Scope of Claims] A magnetic sensor device characterized in that it is configured to drive a magnetoelectric conversion element made of an indium antimony semiconductor material while being cooled to a temperature lower than room temperature using Peltier effect semiconductor means. 2. A magnetoelectric conversion element made from an indium antimony semiconductor material is adhered to a base made of a magnetic material, a heat transfer block is provided around the base, and the block and the base are connected using a Peltier effect semiconductor. It is equipped with an electronic cooling unit that cools the semiconductor to a predetermined temperature lower than room temperature, and is configured such that each of the above components is housed in a heat-insulating housing except for a heat dissipation part, and an adjustable DC current is passed through the semiconductor from a DC power supply, and the A magnetic sensor device characterized by a configuration that improves the output sensitivity of a magnetoelectric conversion element. 3. The base is magnetized, the magnetoelectric conversion element is configured as a magnetoresistive element, and the element is configured to be attached to one magnetic pole surface of the magnetized base. 2
The magnetic sensor device described in .