JPS5969978A - Manufacture of magnetic detector - Google Patents

Abstract

PURPOSE:To contrive to enhance mechanical strength of the whole of a cage body, to enable to prevent also the cage body from invasion of humidity, etc., to enable to form the thin part thin much more, and to enable to enhance also sensitivity of a magnetic detector by a method wherein at the metal cage body to be accommodated with magnetic resistance elements, the wall part of the part to make the magnetic resistance elements to be positioned facing mutually is swelled out to obtain the elemental cage body, and the outside of the swelled part thereof is polished to be thinned to manufacture the metal cage body. CONSTITUTION:The elemental cage body 10 is formed in the condition forming the square tube type of uniform thickness and having the closed upper edge part formed by applying the drawing process to a brass plate, and moreover, having the central part of the upper wall swelled out outside, thereat the magnetic resistance elements 7, 8 are to be faced mutually. Size of the swelled out part 11a to be swelled out outside at the upper wall of the elemental cage body 10 is made slightly smaller than size of thickness of the elemental cage body 10, then the outside wall of the swelled out part 11a is polished up to the position shown with the broken line, and the outside of the swelled out part 11a is finished to a flat surface as to make the same plane with the circumferential surface. Accordingly, the main body part 11 of the magnetic detector is formed having the outside flat surface at the center of the upper part wall, having a concave 11b inside, and being furnished with the thin part 11c of thickness of the degree of 0.1mm..

Description

【発明の詳細な説明】 本発明は磁界の変化に応じて抵抗値が変化する磁気抵抗
素子を用いた磁気検出器の製造方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a magnetic detector using a magnetoresistive element whose resistance value changes in response to changes in a magnetic field.

ＩｎＳｂ、　Ｉｎ５ｂ−ＮｉＳｂ、　ＩｎＡｓ等のキャ
リヤ移動度の高い半導体又／ｄ　Ｎｉ−Ｃｏ　、　Ｎｉ
−Ｆｅ　、　Ｎ１−Ｆｅ−Ｃ。Semiconductors with high carrier mobility such as InSb, In5b-NiSb, InAs or /dNi-Co, Ni
-Fe, N1-Fe-C.

等の強磁性体はこれに作用する磁界の状態に応じて抵抗
値が変化するという性質を有しており、この性質を利用
して磁気の存在、磁性体の存在、移動を検出する磁気検
出器が実用化されている。Ferromagnetic materials, such as The device has been put into practical use.

第１図は従来の磁気検出器を示す正面断面図であり、図
中２１は筐体を示している。筐体２１はプラスチックを
素材として一体成形されており、上面に形成した開口部
２．１ａはべＩＪ　ＩＪクムー銅製のｗｉＭよりなる保
護板２２にて閉鎖されている。保１度板２２ｔ／ｉ筐体
２１に一体にモールドされており、その外面には耐摩耗
性向上のために必要に応じてクロムメッキが施される。FIG. 1 is a front sectional view showing a conventional magnetic detector, and numeral 21 in the figure indicates a housing. The casing 21 is integrally molded from plastic, and an opening 2.1a formed on the top surface is closed with a protection plate 22 made of WiM copper. The protection plate 22t/i is integrally molded with the housing 21, and its outer surface is chrome plated as necessary to improve wear resistance.

筐体２１内にはこの保護板２２と適当なｌ１１隙を隔て
てセンサユニット２３が配設されている。センキュニッ
ト２３はフェライト製の磁性体基板２４上に接着用樹脂
２５を用いて磁気抵Ｕし素子２６゜２７を並設したもの
であり、この磁性体基１２４はプラスチック製のマクン
ト基板２８に穿設した穴に嵌合され、マクント基板２８
下１ｒｒｉのＩＪン青剣１間製の底板２８′を介して、
′その下面をノ（イアス用の永久磁石２９に対向させで
ある。マクレ）Ｍ板２８上にはセンサユニット２３を囲
続する環状スペーサ３０が設けられており、保護板２２
の周縁に８斐スペーサ３０の上面を接触させて保護板２
２と磁気抵抗素子２６．２７との間隔が所定値に々るよ
うにしである。各磁気抵抗素子２６．２７から引き出さ
れたリードはマクント基板２８上のプリント配線を経、
筐体２１の内壁面に設けたターミナル３１に一旦あずけ
た後、底板を通して外部に導出されているリード線３２
に接続されている。A sensor unit 23 is disposed within the housing 21 with an appropriate l11 gap away from the protective plate 22. The Sencunit 23 has magnetic resistive elements 26 and 27 arranged side by side on a magnetic substrate 24 made of ferrite using an adhesive resin 25, and this magnetic substrate 124 is perforated in a Macnto substrate 28 made of plastic. The macanto board 28 is fitted into the provided hole.
Through the bottom plate 28' made of IJn Aoken 1m of the lower 1rri,
'An annular spacer 30 surrounding the sensor unit 23 is provided on the M plate 28 with its lower surface facing the permanent magnet 29 for the ear.
The upper surface of the 8-spacer 30 is in contact with the periphery of the protective plate 2.
2 and the magnetoresistive elements 26 and 27 are set to a predetermined value. The leads drawn out from each magnetoresistive element 26 and 27 pass through the printed wiring on the Macintosh board 28,
The lead wire 32 is once placed in a terminal 31 provided on the inner wall of the housing 21 and then led out through the bottom plate.
It is connected to the.

なお筐体２１内の空間部にはエポキシ樹脂（図示せず）
等が充填せしめられる。Note that the space inside the housing 21 is filled with epoxy resin (not shown).
etc. are filled.

ところでこのような従来の磁気検出器の筐体はプラスチ
ック製としであるが、これは成形性に優ハ、このために
磁気検出器自体の組立及び磁気検出器の装置への取付は
等の作業性９便宜性の向上のための形状面での工夫を講
じ易く、コスト面でも安価であること等による。By the way, the housing of such conventional magnetic detectors is made of plastic, which has excellent moldability, which makes assembly of the magnetic detector itself and attachment of the magnetic detector to the device difficult. Characteristic 9: It is easy to take measures in terms of shape to improve convenience, and it is inexpensive in terms of cost.

通常磁気検出器は保護板２２が被検物移動域に臨み又は
これと摺接するように使用されるのであるが、検出感度
を高めるべくリード線３２に高増幅度の増幅器を接続す
る場合は、磁気抵抗素子２６゜２７、或は筐体内導体部
分が受ける静電誘導の影響により誤検出を招来するとい
う問題点がある。Normally, a magnetic detector is used so that the protection plate 22 faces or comes into sliding contact with the area of movement of the object to be measured, but when connecting a high-amplification amplifier to the lead wire 32 to increase detection sensitivity, There is a problem in that erroneous detection occurs due to the influence of electrostatic induction on the magnetoresistive elements 26 and 27 or the conductor portion within the housing.

また保護板２２表面を摺接させて磁気インクを用いてい
る紙幣の識別に使用する場合には保護板２２周縁のプラ
スチックと紙幣の紙との摩擦により静電気が発生して筐
体が帯電し、これが素子２６゜２７又はこれに連なる′
電気回路に放電して素子又Ｉ／′ｉ前述した如き増幅器
等を破壊するという問題点がある。また摩擦以外の理由
によっても放電が生じることがあるが、この場合の電撃
に対しても素子等は無防備であり破壊の危険に曝されて
いる。In addition, when the surface of the protection plate 22 is used to identify banknotes using magnetic ink by sliding the surface of the protection plate 22, static electricity is generated due to friction between the plastic around the periphery of the protection plate 22 and the paper of the banknote, and the casing is charged. This is element 26゜27 or connected to it'
There is a problem in that it discharges into the electric circuit and destroys the device or the amplifier as mentioned above. Discharge may also occur due to reasons other than friction, but the elements are defenseless against electric shock in this case and are exposed to the risk of destruction.

このため木発明者匈は上述した如き静電誘導、静電気放
電の防止を図り、まだ筐体全体の強度を図るために金属
製筐体を用いることを着想するに至ったが、筐体を金属
製とする場合には次のような問題がある。即ち、検出精
度を向上させるためには、センサユニット２３を構成す
る磁気抵抗素子２６．２７と被検物との離隔寸法はこれ
を小さくするのが望ましいが、そのためには磁気抵抗素
子２６．２７と対向する部分の筐体の肉厚はこれを可及
的に薄く形成する必要があり、一方筐体の他の部分は実
用的強度を維持するだめに、所定の厚さ忙形成する必要
があるが、このような局部的に肉厚の異なる筐体を金属
にて絞り加工するのけ極めて難しい。For this reason, the inventor of wood, Xiong, came up with the idea of using a metal casing to prevent the electrostatic induction and electrostatic discharge as described above, and to increase the overall strength of the casing. There are the following problems when using a manufactured product. That is, in order to improve detection accuracy, it is desirable to reduce the distance between the magnetoresistive elements 26, 27 that constitute the sensor unit 23 and the object to be measured. The wall thickness of the casing at the part facing the casing must be as thin as possible, while the other parts of the casing must be formed to a predetermined thickness in order to maintain practical strength. However, it is extremely difficult to draw metal into such cases where the wall thickness varies locally.

本発明はかかる事情に鑑みなされたものであって、その
目的とするところは磁気抵抗素子を収納すべき金属製筐
体を、磁気抵抗素子を対向位置させるべき部分の壁部を
外方に膨出せしめた筐素体を得、その膨出部の外面を研
厚し、薄肉化することによって製造することにより、厚
肉部分と薄肉部分とを有する筐体を容易に製造すること
が出来て筐体全体の機械的強度が大きく、外部からの湿
気等の侵入も防止出来、まだ薄肉部分はより蒔く成形出
来て感度の向上も図れるようにした磁気検出器の製造方
法を提供するにある。The present invention has been made in view of the above circumstances, and an object of the present invention is to expand a metal casing in which a magnetoresistive element is to be housed so that the wall portion of the portion where the magnetoresistive element is to be positioned facing the part is expanded outwardly. By obtaining a protruding casing body, grinding the outer surface of the protruding portion, and making the wall thinner, it is possible to easily manufacture a casing having a thick portion and a thin portion. To provide a method for manufacturing a magnetic detector in which the mechanical strength of the entire casing is high, the intrusion of moisture etc. from the outside can be prevented, thin parts can be molded more tightly, and sensitivity can be improved.

以下本発明方法をその実施状態を示す図面に基いて具体
的に説明する。第２図は本発明方法に係る磁気検出器の
製造方法により得た磁気検出器の正面断面図、第３図は
同じく部分破砕側面図、第４図（イ）、（ロ）は本発明
方法による筐体の製造工程を示す説明図であり、図中１
は筐体、１１は筐体１を構成する本体部分、１２は底板
部分を示している。Hereinafter, the method of the present invention will be specifically explained based on the drawings showing its implementation state. Fig. 2 is a front sectional view of a magnetic detector obtained by the method of manufacturing a magnetic detector according to the method of the present invention, Fig. 3 is a partially fragmented side view of the same, and Figs. 4 (a) and (b) are the method of the present invention. 1 is an explanatory diagram showing the manufacturing process of the casing by
11 is a main body portion of the housing 1, and 12 is a bottom plate portion.

本体部分１１は黄が１１を素祠にして上端部を閉鎖され
、四隅部に若干の丸味を与えた四角筒状に形成され、下
端部は底板）１１ｚ分１２にて閉鎖され、内部にはマク
ント基板２、センサユニット３、永久磁石４等が配設さ
九、センサユニット３のスペーサ５で囲われた部分を除
く他の空間部には合成樹脂が充填せ°しめられている。The main body part 11 is formed into a rectangular tube shape with a yellow color 11 as a base plate, the upper end is closed, and the four corners are slightly rounded, and the lower end is closed with a bottom plate) 11z min 12, and the inside is The Macintosh board 2, the sensor unit 3, the permanent magnet 4, etc. are arranged, and the other space except the part surrounded by the spacer 5 of the sensor unit 3 is filled with synthetic resin.

この本体部分１１は先ず、第４図（イ）に示す如く黄銅
板に絞り加工を施して上端部が閉鎖された肉厚が一様（
０，５ａｍ程度）な四角筒形を々し、且つ、磁気抵抗素
子７．８を対向させるべき上部壁の中央部を゛外方に膨
出せしめた状態の筐素体１０を成形する。筐素体１０の
上部壁における膨出部１１ａの外方への）膨出寸法は筐
素体１０の肉厚寸法よりも僅かに小さくしておき、次い
で第４図（ロ）に示す如く１膨出部１１ａの外壁を破線
で示す位置迄研摩し、膨出部１１ａ外面をその周囲の面
と面一となるよう平坦面に仕上げる。This main body part 11 is first made by drawing a brass plate, as shown in FIG.
A casing body 10 is formed into a rectangular cylindrical shape with a diameter of about 0.5 am), and in which the center portion of the upper wall where the magnetoresistive element 7.8 is to be opposed is bulged outward. The outward bulging dimension of the bulging portion 11a on the upper wall of the housing body 10 is made slightly smaller than the wall thickness dimension of the housing body 10, and then, as shown in FIG. The outer wall of the bulge 11a is polished to the position shown by the broken line, and the outer surface of the bulge 11a is finished to be flat so that it is flush with the surrounding surface.

これによって上部壁の中央に外面が平坦面であって内面
に凹みｌｌｂを有し、肉厚が０．１　ｔｍ程度の薄肉部
分１１ｃを備えた本体部分１１が形成される。As a result, a main body portion 11 having a flat outer surface, a recess llb on the inner surface, and a thin portion 11c having a wall thickness of approximately 0.1 tm is formed at the center of the upper wall.

なお、本体部分１１の形成態様については特に上述した
態様にのみ限定するものではなく、例えば第５図（イ）
に示す如く、絞り加工によって形成される筐素体１０′
の上部量における膨出部１１’ａの周縁部からのＩＦｒ
出寸法を肉厚以上とし、次いで膨出部１１′ａ外面を破
線で示す如＜　０．１　ｍｍ程度のｊ９．さに迄研摩し
て第５図（ロ）に示す如く内面に凹み１１′ｂを有し、
薄肉部分１１′ｃを備えた本体部分１１’を形成しても
よい。Note that the form of the main body portion 11 is not limited to the above-mentioned form, for example, as shown in FIG.
As shown in the figure, a housing body 10' formed by drawing process
IFr from the peripheral edge of the bulge 11'a at the upper amount of
The protrusion dimension is set to be greater than the wall thickness, and then the outer surface of the bulged portion 11'a is approximately <0.1 mm j9. as shown by the broken line. It is polished to the point where it has a recess 11'b on the inner surface as shown in Figure 5 (b).
The body portion 11' may be formed with a thinned portion 11'c.

底板部分１２は例えばプラスチック成形品であって本体
部分１１の下端開口部に底合固定されている。The bottom plate portion 12 is, for example, a plastic molded product, and is fixed to the lower end opening of the main body portion 11 at the bottom.

マクント基板２は前記した各部材によって形成される筐
体１内に本体部分１１の薄肉部分１１ｃ（１１’ｃ　）
に而して位置し、薄肉部分１１Ｃ（１１’Ｃ）の下面に
上端部を突き当てたスペーサ５によりこれと所要の間隔
を隔てて配設され、上面には凹み１ｌｂ（１１’ｂ　）
内に位置してセンサユニット３が、また下面には円柱状
の永久磁石４の一磁極端面が固定されでいる。センサユ
ニット３はマクント基板２上簡の磁性体基板６上に接着
用樹脂６ａを用いて２個の磁気抵抗素子７，８を並列固
定して形成され、各磁気抵抗素子７，８から引き出した
リードはマクント基板２に穿った孔を通してその下面に
導か九、ここでリード板９ａ、９ｂ、９ｃの各一端に接
続されており、その各他喘ｐまｌＬ′ｃ板８１板針１５
分１２た孔を通してその下方に夫々所製長にわたって延
在されている。９ｄｌ″ｉ、筐体１の本体部分１１内面
に一端を接続されたアース用のリード板であってその他
＠は同じく底板８ｆ≦分１２に穿った孔を通してその下
方に延在せしめられている゛。The Macintosh board 2 has a thin wall portion 11c (11'c) of the main body portion 11 inside the casing 1 formed by the above-mentioned members.
A spacer 5 whose upper end abuts against the lower surface of the thin-walled portion 11C (11'C) is placed at a required distance from the lower surface of the thin-walled portion 11C (11'C).
A sensor unit 3 is located inside, and one pole end face of a cylindrical permanent magnet 4 is fixed to the bottom surface. The sensor unit 3 is formed by fixing two magnetoresistive elements 7 and 8 in parallel on a magnetic substrate 6 on the top of the Makunto board 2 using an adhesive resin 6a, and a sensor unit 3 is formed by fixing two magnetoresistive elements 7 and 8 in parallel on a magnetic substrate 6 on the top panel of the Makunto board 2. The leads are guided to the bottom surface of the Macintosh board 2 through holes drilled in it, where they are connected to one end of each of the lead plates 9a, 9b, and 9c, and are connected to the other ends of the lead plates 81 and 15.
The holes extend downwardly for a given length through the rounded holes. 9dl''i is a grounding lead plate whose one end is connected to the inner surface of the main body part 11 of the casing 1, and the other part is similarly extended downward through a hole bored in the bottom plate 8f≦min12. .

本発明にあっては筐体１を金１１似製とし、磁気抵抗素
子７，８を対向させるべき部分の壁部を外方に膨出せし
めた筐素体１０．１０’を得、この筐素体１０．１０’
における膨出部１１ａ、ｌｌ’ａを研摩し、薄肉化して
製造することとしているから、表面が平滑であって、従
来の如く筐体と保護板との間における如き段差が形成さ
れず、被検物が係止する等の不都合がなく、またｔＩ肉
化部分１１ｃ、ｌｌ’ｃけ周縁部が厚内部分に一体的に
連らなっているため、強度が大きく、より薄肉化するこ
とも可能で、検出感度の大Ｉｌｖ、ｔな向上も図れる。In the present invention, the casing 1 is made of gold 11 imitation, and a casing body 10.10' is obtained in which the wall portion of the portion where the magnetoresistive elements 7 and 8 are to face bulges outward. Prime body 10.10'
Since the protrusions 11a and ll'a are polished and manufactured to have a thinner wall, the surface is smooth and there is no difference in level between the casing and the protective plate as in the conventional case. There is no inconvenience such as the specimen getting stuck, and since the tI thickened portion 11c and the ll'c peripheral edge are integrally connected to the thick inner portion, the strength is high and the thickness can be made even thinner. It is possible to achieve a significant improvement in detection sensitivity.

更に被検物との摩擦によってＷ擦電気が生じてもアース
用リード板９ｄを通じて放電されることとなり、静電＠
導、電撃等からも磁気抵抗素子７．８を保護することが
出来る。しかも筐体ｌは底板部分１２を除いて一体的に
形成されるため、気密性が高く、湿気の　゛侵入による
磁気抵抗素子７．８の特性劣化も生じない。Furthermore, even if W frictional electricity is generated due to friction with the test object, it will be discharged through the grounding lead plate 9d, and static electricity@
The magnetoresistive element 7.8 can also be protected from conduction, electric shock, and the like. Moreover, since the casing 1 is integrally formed except for the bottom plate portion 12, it is highly airtight, and the characteristics of the magnetoresistive elements 7.8 do not deteriorate due to the intrusion of moisture.

以上の如く本発明方法にあっては筐体を金ＪＦＡ製であ
ってしかも部分的に肉厚を異ならせる必要のある筐体を
一体成形することが出来て筐体全体としての機械的強度
が大きく、また静電誘導、電撃から磁気抵抗素子を保護
することが出来、更に筐体内部の気密性が高く、湿気等
の侵入を確実に防止でき、更に痩肉化部分を一層薄く形
成出来るため被検物と磁気抵抗素子との離隔寸法をｇｒ
ｊ縮出米゛゛て検出精度を大幅に向上し得・る橙ど木発
ＦＪＡは優れた効果を奏するものである。As described above, in the method of the present invention, the casing is made of gold JFA, and the casing, which needs to have different wall thicknesses in parts, can be integrally molded, and the mechanical strength of the casing as a whole is improved. It is large and can protect the magnetoresistive element from electrostatic induction and electric shock, and the inside of the housing is highly airtight, reliably preventing moisture from entering.Furthermore, the thinned part can be made even thinner. The distance between the test object and the magnetoresistive element is gr
FJA made from orange wood can greatly improve the detection accuracy by shrinking rice, and has an excellent effect.

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

第１図は従来の磁気検出器の正面断面図、第２図は本発
明方法により製造した磁気検出器の正面断面図、第３図
は同じく部分破砕側面図、第４図（イ）、（ロ）は本発
明方法による筐体の製進態様を示す説明図、第５図（イ
）、（ロ）は同じく筺体の他の製造態様を示す説明図で
ある。 ｌ・・・筐体、２・・・マクント２（１＆　　３・、セ
ンサユニット　４・・・永久磁石　５・・・スペーサ　
６・・・イ庭性体基板　６ａ・・・接着剤　７，８・・
・磁気４］Ｕ抗素子９ａ、９Ｊ　　９ｃ、９ｄ−−−リ
ード板　　１０．　１０’　・・・筺素体１１、１１’
・＝本体部分　１１　ａ　、　１１’ａ”・、ｌｊｉ出
部１１ｂ、　ｌｌ’ｂ　−凹所　１１ｃ、　ｌｌ’ｃ　
＝Ｊ＃肉１１１３分　１２・・底板部分 特許出願人　　三洋′改機株式会社 外１名 代理人　弁理士　　河　野　登　夫 第３図 第４図　　　　　　１５１FIG. 1 is a front sectional view of a conventional magnetic detector, FIG. 2 is a front sectional view of a magnetic detector manufactured by the method of the present invention, FIG. 3 is a partially fragmented side view, and FIGS. B) is an explanatory view showing a manufacturing process of the casing according to the method of the present invention, and FIGS. 5A and 5B are explanatory views showing another manufacturing process of the casing. l... Housing, 2... Macunto 2 (1 & 3), sensor unit 4... Permanent magnet 5... Spacer
6... Inner body substrate 6a... Adhesive 7,8...
・Magnetic 4] U anti-element 9a, 9J 9c, 9d---Lead plate 10. 10' ... Housing body 11, 11'
・=Body part 11a, 11'a"・, lji Extrusion part 11b, ll'b - Recess 11c, ll'c
= J # Meat 1113 minutes 12... Bottom plate portion Patent applicant Sanyo' Kaiki Co., Ltd. and one other agent Patent attorney Noboru Kono Figure 3 Figure 4 151

Claims (1)

【特許請求の範囲】[Claims] １、磁気抵抗素子を収納すべき金属製筐体を、磁気抵抗
素子を対向位置させるべき部分の壁部を外方に膨出せし
めた筐素体を得、その膨出部の外面を研摩し、薄肉化す
ることによって製造することを特徴とする磁気検出器の
製造方法。1. Obtain a metal casing in which the magnetoresistive element is to be housed, in which the wall portion of the part where the magnetoresistive element is to be positioned opposite to each other is bulged outward, and the outer surface of the bulge is polished. , a method for manufacturing a magnetic detector, characterized in that the magnetic detector is manufactured by thinning.