JPH0726856B2 - Sensor device - Google Patents
Sensor deviceInfo
- Publication number
- JPH0726856B2 JPH0726856B2 JP1078475A JP7847589A JPH0726856B2 JP H0726856 B2 JPH0726856 B2 JP H0726856B2 JP 1078475 A JP1078475 A JP 1078475A JP 7847589 A JP7847589 A JP 7847589A JP H0726856 B2 JPH0726856 B2 JP H0726856B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic core
- coil
- detected
- amount
- magnetic
- 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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- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、所定の被検出量に応じて移動される磁芯を有
し、該磁芯の移動により被検出量に応じた信号を出力す
るセンサ装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention has a magnetic core that is moved according to a predetermined amount of detection, and outputs a signal according to the amount of detection by the movement of the magnetic core. The present invention relates to a sensor device.
従来この種のセンサ装置として、第５図（ａ）及び
（ｂ）の如く構成された差動トランスが使用されてい
る。同図において、１次コイルL3には交流電圧が供給さ
れ、該１次コイルL3と電磁的に２つの差動２次コイルL
4a，L4bが結合されている。また、１次コイルL3が発生
する磁界中には直線移動する磁芯１が設けられている。Conventionally, as this type of sensor device, a differential transformer configured as shown in FIGS. 5A and 5B is used. In the figure, the primary coil L 3 is supplied AC voltage, the primary coil L 3 and electromagnetically two differential secondary coil L
4a and L 4b are combined. Further, a magnetic core 1 that moves linearly is provided in the magnetic field generated by the primary coil L 3 .
上記磁芯１は動力伝達手段（図示せず）により被検出部
に連結され、ジーゼルエンジンの噴射ポンプのスロット
ル量、アクセルペダルの角度、燃料レベル量等の所定の
被検出量に応じたストローク（移動距離）で移動され
る。なお、各コイルL3，L4a，L4bはボビン２に巻装され
ている。The magnetic core 1 is connected to a detected portion by a power transmission means (not shown), and a stroke (according to a predetermined detected amount such as a throttle amount of an injection pump of a diesel engine, an accelerator pedal angle, a fuel level amount, etc.) It is moved by the moving distance). The coils L 3 , L 4a and L 4b are wound around the bobbin 2.
以上の構成において、１次コイルL3と差動２次コイルL
4a，L4bとは電磁的に結合しているが、このとき１次コ
イルL3が発生する磁界中に磁芯１が配置されると、その
相互インダクタンスが変化し、２次コイルL4a，L4bより
出力される各誘起電圧が変化する。該相互インダクタン
スは前記磁界中に磁芯１が配置される長さ、すなわち磁
芯１のストロークに応じて変化するので、結局前記２次
コイルL4a，L4bよりの各誘起電圧は磁芯１のストローク
に応じて変化する。上記差動２次コイルL4a，L4bより得
られる２つの誘起電圧は差動アンプ（図示せず）に入力
され、両者の電圧の差の電圧を増幅することにより、磁
芯１のストロークに応じた差動アンプの出力にて表示部
（図示せず）を駆動して被検出量を表示することができ
るようになる。In the above configuration, the primary coil L 3 and the differential secondary coil L
4a and L 4b are electromagnetically coupled, but when the magnetic core 1 is placed in the magnetic field generated by the primary coil L 3 at this time, the mutual inductance changes and the secondary coil L 4a , Each induced voltage output from L 4b changes. Since the mutual inductance changes according to the length of the magnetic core 1 arranged in the magnetic field, that is, the stroke of the magnetic core 1, each induced voltage from the secondary coils L 4a and L 4b is eventually the magnetic core 1. Changes according to the stroke. The two induced voltages obtained from the differential secondary coils L 4a and L 4b are input to a differential amplifier (not shown), and the stroke of the magnetic core 1 is changed by amplifying the difference voltage between the two voltages. A display unit (not shown) can be driven by the output of the corresponding differential amplifier to display the detected amount.
上述した従来のセンサ装置にあっては、高精度の検出出
力が得られるものの、磁芯１のストロークを精度よく検
出できるには、磁芯１の有効ストロークに対して、１次
コイルL3及び２次コイルL4a，L4bの磁芯１方向の長さは
約３倍必要である。すなわち、第５図（ｂ）のボビン２
の長さｌ′は有効ストロークの３倍必要である。従っ
て、コイル及びコイルボビンが大きくなり小型化するこ
とができない。また、ストロークに対する検出出力（誘
起電圧）の調整が難しいため、コストを安くすることも
難しい。In the above-described conventional sensor device, although a highly accurate detection output can be obtained, in order to detect the stroke of the magnetic core 1 with high accuracy, the primary coil L 3 and The length of the secondary coils L 4a and L 4b in the direction of the magnetic core 1 is required to be about three times as long. That is, the bobbin 2 of FIG. 5 (b)
The length l'of is required to be three times the effective stroke. Therefore, the coil and the coil bobbin are increased in size, and the size cannot be reduced. Further, it is difficult to reduce the cost because it is difficult to adjust the detection output (induced voltage) with respect to the stroke.
よって本発明は、所定の被検出量に応じて移動される磁
芯を有し、該磁芯の移動により被検出量に応じた信号を
出力する高精度でかつ小型化できるセンサ装置を提供す
ることを課題としている。Therefore, the present invention provides a sensor device that has a magnetic core that is moved according to a predetermined amount to be detected, and that outputs a signal according to the amount to be detected due to the movement of the magnetic core, which is highly accurate and can be downsized. That is the issue.
上記課題を解決するため本発明により成されたセンサ装
置は、所定の被検出量に応じて移動される磁芯を有し、
該磁芯の移動により被検出量に応じた信号を出力するセ
ンサ装置において、交流電圧が供給される励磁コイル
と、該励磁コイルと交差して巻回された検出コイルとを
備え、互いに交差して巻回した前記励磁コイル及び前記
検出コイルに共通する中空部の略中央を通るように前記
磁芯を移動させて両コイル間の磁気結合を変化させ、前
記磁芯の移動に応じて前記磁芯の移動量に応じた誘起電
圧を前記検出コイルに誘起させ、該誘起電圧により所定
の被検出量を検知するようにしたことを特徴としてい
る。To solve the above problems, the sensor device according to the present invention has a magnetic core that is moved according to a predetermined amount to be detected,
A sensor device that outputs a signal according to a detected amount by moving the magnetic core includes an exciting coil to which an AC voltage is supplied, and a detecting coil wound so as to intersect with the exciting coil and to intersect with each other. The magnetic core is moved so as to pass through substantially the center of the hollow portion common to the exciting coil and the detection coil wound around the coil, and the magnetic coupling between the two coils is changed, and the magnetic core is moved according to the movement of the magnetic core. It is characterized in that an induced voltage according to the amount of movement of the core is induced in the detection coil, and a predetermined amount to be detected is detected by the induced voltage.
上記構成において、励磁コイルと検出コイルが互いに交
差して巻回されているので、励磁コイルが発生する磁界
による磁束は検出コイルと殆ど鎖交することがなく、磁
芯が励磁コイルと検出コイルとを磁気結合させるのに寄
与しない位置にあるときには、検出コイルには誘起電圧
は殆ど出力されない。これに対し、磁芯が励磁コイルと
検出コイルとの磁気結合に寄与する位置に存在するとき
には、その位置に応じて磁気結合の大きさが変化され、
磁芯の位置に応じた大きさの誘起電圧が検出コイルに誘
起されるので、この誘起電圧の大きさによって、所定の
被検出量を検知することができる。In the above configuration, since the exciting coil and the detecting coil are wound so as to intersect with each other, the magnetic flux generated by the magnetic field generated by the exciting coil hardly intersects with the detecting coil, and the magnetic core has the exciting coil and the detecting coil. When it is in a position that does not contribute to the magnetic coupling of, the induced voltage is hardly output to the detection coil. On the other hand, when the magnetic core exists at the position that contributes to the magnetic coupling between the exciting coil and the detection coil, the magnitude of the magnetic coupling is changed according to the position,
Since the induced voltage having a magnitude corresponding to the position of the magnetic core is induced in the detection coil, a predetermined amount to be detected can be detected by the magnitude of the induced voltage.
また、励磁コイルと検出コイルが互いに交差して巻回さ
れ、磁芯が両コイルに共通する中空部の略中央を通るよ
うに移動されるようになっているので、両コイルは磁芯
の移動方向に対して傾斜されて配されるようになり、磁
芯が両コイル間の磁気結合に変化させる範囲が各コイル
の巻回幅に比べて大幅に広がって磁芯の有効ストローク
が大きくなっている。Further, since the exciting coil and the detecting coil are wound so as to intersect with each other and the magnetic core is moved so as to pass through substantially the center of the hollow portion common to both coils, both coils move the magnetic core. The magnetic core is changed to the magnetic coupling between the two coils, and the effective range of the magnetic core is increased. There is.
以下、本発明の実施例を図面に基づいて説明する。 Embodiments of the present invention will be described below with reference to the drawings.
第１図（ａ）及び（ｂ）は本発明によるセンサ装置の一
実施例をそれぞれ示す外観図及び断面図であり、同図に
おいて、励磁コイルL1はそれに所定の交流電圧が供給さ
れ磁界を発生する。また、該励磁コイルL1と略直交する
ように検出コイルL2が巻回される。更に、磁芯１は互い
に交差して巻回した励磁コイルL1及び検出コイルL2に共
通する中空部の略中央を通るように直線移動可能に配置
され、磁芯１は図示しない動力伝達機構を介して被検出
部に連結されその移動量が被検出量に対応するようにさ
れる。なお、各コイルL1，L2は、中心部に磁芯案内部2a
を有するボビン２に巻回されている。1 (a) and 1 (b) are an external view and a sectional view, respectively, showing an embodiment of a sensor device according to the present invention, in which an exciting coil L 1 is supplied with a predetermined alternating voltage to generate a magnetic field. Occur. Further, the detection coil L 2 is wound so as to be substantially orthogonal to the exciting coil L 1 . Further, the magnetic core 1 is arranged so as to be linearly movable so as to pass through substantially the center of a hollow portion common to the exciting coil L 1 and the detecting coil L 2 wound so as to cross each other, and the magnetic core 1 is not shown in the power transmission mechanism. It is connected to the detected part through the so that the movement amount corresponds to the detected amount. Each coil L 1 and L 2 has a magnetic core guide 2a at the center.
Is wound on a bobbin 2 having
以上の構成において、その動作を第３図と共に説明す
る。The operation of the above configuration will be described with reference to FIG.
まず、磁芯１が励磁コイルL1が発生する磁界中にないと
きには、この磁界による磁束φ0は図示のように検出コ
イルL2の巻装方向と略同一の方向に発生するため、励磁
コイルL1と検出コイルL2との電磁結合は粗となり、検出
コイルL2には誘起電圧は殆ど出力されない。First, when the magnetic core 1 is not in the magnetic field generated by the exciting coil L 1 , the magnetic flux φ 0 due to this magnetic field is generated in substantially the same direction as the winding direction of the detection coil L 2 as shown in the figure, so the exciting coil The electromagnetic coupling between L 1 and the detection coil L 2 becomes coarse, and the induced voltage is hardly output to the detection coil L 2 .
一方、磁芯１が磁界中にあると、検出コイルL2は、 で表される誘起電圧E2を出力する。On the other hand, when the magnetic core 1 is in the magnetic field, the detection coil L 2 is The induced voltage E 2 represented by is output.
ここで、E1は励磁コイルL1に供給される交流電圧、n1及
びn2はそれぞれ励磁コイルL1及び検出コイルL2の巻数で
ある。また、Ｋは励磁コイルL1と検出コイルL2との結合
度合を示す結合係数である。この結合係数Ｋは磁芯１が
磁界中に存在するストロークに比例して変化し、E1／
（n1，n2）は一定であるので、（１）式より誘起電圧E2
は磁芯１のストロークに比例して変化する。従って、該
誘起電圧E2より磁芯１の移動量すなわちストークを検出
することができ、このストロークは被検出量に対応して
いるので、結局誘起電圧E2より被検出量を求めることが
できる。Here, E 1 is the AC voltage supplied to the exciting coil L 1 , and n 1 and n 2 are the numbers of turns of the exciting coil L 1 and the detecting coil L 2 , respectively. Further, K is a coupling coefficient indicating the degree of coupling between the exciting coil L 1 and the detecting coil L 2 . This coupling coefficient K changes in proportion to the stroke in which the magnetic core 1 exists in the magnetic field, and E 1 /
Since (n 1 , n 2 ) is constant, the induced voltage E 2 can be calculated from the equation (1).
Changes in proportion to the stroke of the magnetic core 1. Therefore, it is possible to detect the movement amount i.e. stalk of the magnetic core 1 from the induced voltage E 2, the stroke so corresponds to the detected amount, eventually it is possible to obtain the detected amount than the induced voltage E 2 .
ここで、磁芯１の有効ストローク長は励磁コイルが発生
している磁界中に配置される長さであるから、第１図
（ｂ）に示すように交差して配置された２つのコイル
L1，L2の巻幅ｌとなる。従って磁芯１のストロークに対
する誘起電圧特性は、例えば第３図中の特性曲線のよ
うに略比例した特性となる。Here, since the effective stroke length of the magnetic core 1 is the length arranged in the magnetic field generated by the exciting coil, the two coils arranged to intersect each other as shown in FIG. 1 (b).
It becomes the winding width l of L 1 and L 2 . Therefore, the induced voltage characteristic with respect to the stroke of the magnetic core 1 is substantially proportional to the characteristic curve shown in FIG. 3, for example.
また、第２図は本発明の他の実施例を示し、磁芯１の形
状をその断面積が先端方向に向かって徐々に小さくなる
ようにたニードル形状としたものである。Further, FIG. 2 shows another embodiment of the present invention, in which the shape of the magnetic core 1 is a needle shape whose cross-sectional area is gradually reduced toward the tip.
この構成によれば、磁芯１の有効ストローク、すなわち
励磁コイルL1が発生する磁界中に配置されている磁芯１
の長さに応じて電磁結合の結合係数Ｋが２次的に変化す
る。従って、該結合係数Ｋは有効ストロークの略２乗に
比例するので、（１）式より誘起電圧E2も有効ストロー
クの略２乗に比例して、その特性は第３図中の特性曲線
に示すものなる。According to this configuration, the magnetic core 1 effective stroke of the magnetic core 1, i.e. the exciting coil L 1 is disposed in a magnetic field generated
The coupling coefficient K of the electromagnetic coupling secondarily changes according to the length of the. Therefore, since the coupling coefficient K is proportional to the square of the effective stroke, the induced voltage E 2 is also proportional to the square of the effective stroke according to the equation (1), and its characteristic is shown by the characteristic curve in FIG. It becomes what is shown.
上述した２つの実施例において、つのコイルL1，L2の巻
数n1，n2が等しいとき、（１）式よりＫ＝１の場合には
誘起電圧E2としては、略励磁コイルL1の交流電圧E1あで
の大きなものが得られる。従って、第５図に示す２つの
誘起電圧の差の電圧よりストロークを検出する従来の構
成に対して、本発明では誘起電圧E2より直接ゲージ等の
表示部を駆動できるので、差動アンプ等が不要となる。In the two embodiments described above, one when coil L 1, the number of turns n 1 of L 2, n 2 are equal, (1) The induced voltage E 2 in the case of K = 1 from the equation, substantially the exciting coil L 1 A large AC voltage E 1 is obtained. Therefore, in the present invention, the display unit such as a gauge can be directly driven by the induced voltage E 2 as compared with the conventional configuration in which the stroke is detected from the voltage of the difference between the two induced voltages shown in FIG. Is unnecessary.
また、励磁コイルL1に供給する交流電圧は、発振回路等
の出力を用い、その出力レベルや周波数は、コイルを巻
回するボビンの大きさ等により設定するが、例えばその
周波数は1KHz〜5KHz程度に設定することができる。Further, the AC voltage supplied to the exciting coil L 1 uses the output of the oscillation circuit or the like, and its output level and frequency are set by the size of the bobbin around which the coil is wound, etc., but the frequency is, for example, 1 KHz to 5 KHz. It can be set to a degree.
なお、第２図の実施例では磁芯１を先端方向に徐々に断
面積が小さくなる形状にしているが、逆に先端方向に向
かって徐々に断面積が大きくなるような形状にした場合
には、第３図中の特性曲線に示す特性のものを得るこ
とができる。In the embodiment of FIG. 2, the magnetic core 1 has a shape in which the cross-sectional area gradually decreases in the tip direction, but conversely, when the magnetic core 1 has a shape in which the cross-sectional area gradually increases in the tip direction. Can obtain the characteristic shown by the characteristic curve in FIG.
また第３図中の特性曲線及びに示す特性は磁芯１の
断面積に変化を持たせず、その代わりに励磁コイルL1と
検出コイルL2との交差角度を90゜からずらすことによっ
ても得ることができる。The characteristic curve and the characteristic shown in FIG. 3 do not change in the cross-sectional area of the magnetic core 1, but instead, the crossing angle between the exciting coil L 1 and the detecting coil L 2 is deviated from 90 °. Obtainable.
更にまた、上述の実施例では、磁芯１を直線移動させる
ようにしているが、被検出量の検出を一度回転に変換し
てから行うことが好ましい場合や被検出量が回転角度で
ある場合には、第４図に示すように、回動支点3aについ
て回動自在の回動部材３の一端に円弧状の磁芯１の一端
を直接固着し、回動部材３の回動角度θに応じた移動量
だけ磁芯１を円弧移動させることによって、回動角度θ
の変化に応じた大きさの電圧信号を検出コイルL2の出力
に得ることができ、この電圧信号によって回動角度θに
対応する被検出量或いは被検出量である回動角度θその
ものを検出することができる。Furthermore, in the above-mentioned embodiment, the magnetic core 1 is linearly moved, but it is preferable that the detection of the detected amount is performed after being converted into rotation once, or the detected amount is a rotation angle. As shown in FIG. 4, one end of the arc-shaped magnetic core 1 is directly fixed to one end of the rotating member 3 which is rotatable about the rotating fulcrum 3a, and the rotation angle θ of the rotating member 3 is set. By rotating the magnetic core 1 in an arc by a corresponding movement amount, the rotation angle θ
A voltage signal having a magnitude corresponding to the change of the detection coil L 2 can be obtained at the output of the detection coil L 2 , and the detected voltage corresponding to the rotation angle θ or the rotation angle θ itself which is the detection amount can be detected by this voltage signal. can do.
以上説明したように本発明によれば、励磁コイルと検出
コイルが互いに交差して巻回され、磁芯が両コイルに共
通する中空部の略中央を通るように移動されるようにな
っているので、検出コイルには磁芯の移動量すなわちス
トロークに応じた誘起電圧が誘起され、この誘起電圧の
大きさによって所定の被検出量を高精度に検知すること
ができ、しかも両コイルは磁芯の移動方向に対して傾斜
されて配されるようになり、磁芯が両コイル間の磁気結
合に変化させる範囲が各コイルの巻回幅に比べて大幅に
広がって磁芯の有効ストロークが大きくなっているの
で、形状も小型化することができる他、非接触式なの
で、信頼性も向上し、従ってアクセルペダルセンサや燃
料レベルセンサ等の各種センサに好適である。As described above, according to the present invention, the exciting coil and the detecting coil are wound so as to intersect with each other, and the magnetic core is moved so as to pass through substantially the center of the hollow portion common to both coils. Therefore, an induced voltage is induced in the detection coil according to the amount of movement of the magnetic core, that is, the stroke, and the magnitude of this induced voltage can detect a predetermined amount to be detected with high accuracy. The magnetic core is changed to the magnetic coupling between both coils, and the range in which the magnetic core changes to the magnetic coupling is greatly expanded compared to the winding width of each coil, and the effective stroke of the magnetic core is large. Therefore, the shape can be reduced, and since it is a non-contact type, the reliability is improved, and therefore it is suitable for various sensors such as an accelerator pedal sensor and a fuel level sensor.
第１図（ａ）及び（ｂ）は本発明によるセンサ装置の一
実施例をそれぞれ示す外観図及び断面図、 第２図は本発明によるセンサ装置の他の実施例を示す断
面図、 第３図は本発明によるセンサ装置の出力電圧特性例を示
すグラフ、 第４図は本発明によるセンサ装置の更に他の実施例を示
す断面図、 第５図（ａ）及び（ｂ）は従来のセンサ装置をそれぞれ
示す側面図及び断面図である。 L1…励磁コイル、L2…検出コイル、１…磁芯。1 (a) and 1 (b) are an external view and a sectional view showing an embodiment of the sensor device according to the present invention, respectively, and FIG. 2 is a sectional view showing another embodiment of the sensor device according to the present invention. FIG. 4 is a graph showing an output voltage characteristic example of the sensor device according to the present invention, FIG. 4 is a sectional view showing still another embodiment of the sensor device according to the present invention, and FIGS. 5 (a) and 5 (b) are conventional sensors. It is the side view and sectional drawing which respectively show an apparatus. L 1 ... Excitation coil, L 2 ... Detection coil, 1 ... Magnetic core.
Claims (1)
有し、該磁芯の移動により被検出量に応じた信号を出力
するセンサ装置において、 交流電圧が供給される励磁コイルと、 該励磁コイルと交差して巻回された検出コイルとを備
え、 互いに交差して巻回した前記励磁コイル及び前記検出コ
イルに共通する中空部の略中央を通るように前記磁芯を
移動させて両コイル間の磁気結合を変化させ、 前記磁芯の移動に応じて前記磁芯の移動量に応じた誘起
電圧を前記検出コイルに誘起させ、該誘起電圧により所
定の被検出量を検知するようにした ことを特徴とするセンサ装置。1. A sensor device having a magnetic core that moves according to a predetermined amount to be detected, and outputting a signal according to the amount to be detected by the movement of the magnetic core. An exciting coil to which an AC voltage is supplied. And a detection coil wound so as to intersect with the exciting coil, and the magnetic core is moved so as to pass through substantially the center of a hollow portion common to the exciting coil and the detecting coil wound so as to intersect with each other. The magnetic coupling between the coils is changed to induce an induced voltage in the detection coil according to the movement amount of the magnetic core according to the movement of the magnetic core, and the predetermined detected amount is detected by the induced voltage. The sensor device is characterized in that
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1078475A JPH0726856B2 (en) | 1989-03-31 | 1989-03-31 | Sensor device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1078475A JPH0726856B2 (en) | 1989-03-31 | 1989-03-31 | Sensor device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02259416A JPH02259416A (en) | 1990-10-22 |
| JPH0726856B2 true JPH0726856B2 (en) | 1995-03-29 |
Family
ID=13663040
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1078475A Expired - Fee Related JPH0726856B2 (en) | 1989-03-31 | 1989-03-31 | Sensor device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0726856B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100849971B1 (en) * | 2006-12-28 | 2008-08-01 | 태창엔이티 주식회사 | Terrestrial magnetism rotation sensor |
-
1989
- 1989-03-31 JP JP1078475A patent/JPH0726856B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02259416A (en) | 1990-10-22 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |