JPH0810799Y2 - Current sensor - Google Patents
Current sensorInfo
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- JPH0810799Y2 JPH0810799Y2 JP14289189U JP14289189U JPH0810799Y2 JP H0810799 Y2 JPH0810799 Y2 JP H0810799Y2 JP 14289189 U JP14289189 U JP 14289189U JP 14289189 U JP14289189 U JP 14289189U JP H0810799 Y2 JPH0810799 Y2 JP H0810799Y2
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- Japan
- Prior art keywords
- detected
- current
- coil
- detection
- signal
- Prior art date
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- Expired - Lifetime
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- Measurement Of Current Or Voltage (AREA)
Description
【考案の詳細な説明】 〔産業上の利用分野〕 本考案は、変流形センサーに係り、特にバイアス電流
に重畳された被検出電流を検出するのに好適な変流形セ
ンサーに関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a current-changing sensor, and more particularly to a current-changing sensor suitable for detecting a current to be detected which is superimposed on a bias current.
従来、バイアス電流に重畳された被検出電流を検出す
る変流形センサーとしては、第2図に示す如きものが使
用されていた。該センサーは、バイアス電流に被検出電
流を重畳させて供与される被検出コイル1をコア2に巻
回させておき、該コア2には互いに逆巻きにした検出コ
イル3a,3bを巻装させてある。該検出コイル3a,3bの共通
端子にはバイパスコンデンサC1を介して(−)端子GND
に接続し、一方の検出コイル3aの他端は比較器IC1の
(−)端子に、又検出コイル3bの他端は比較器IC1の
(+)端子にそれぞれ接続する。比較器IC1の出力端子
は抵抗R6を介してバッファーアンプIC2に接続させてあ
り、該バッファーアンプIC2から検出信号を出力するよ
うになっている。尚、第1図において、C2はノイズ除
去用コンデンサー、C3は平滑用コンデンサ、R1〜
R5、R7〜R9は抵抗、VCCは直流電源である。Conventionally, as a current-changing type sensor for detecting a current to be detected which is superimposed on a bias current, a current sensor as shown in FIG. 2 has been used. In this sensor, a coil to be detected 1 provided by superimposing a current to be detected on a bias current is wound around a core 2, and detection coils 3a and 3b wound in opposite directions are wound around the core 2. is there. Detection coils 3a, the common terminal of 3b via the bypass capacitor C 1 (-) terminal GND
Connected to the other end of one of the detection coils 3a is a comparator IC 1 (-) terminal, and the other end of the detection coil 3b are connected to the (+) terminal the comparator IC 1. The output terminal of the comparator IC 1 is connected to the buffer amplifier IC 2 via the resistor R 6 , and the detection signal is output from the buffer amplifier IC 2 . In FIG. 1, C 2 is a noise removing capacitor, C 3 is a smoothing capacitor, and R 1 to
R 5, R 7 ~R 9 resistance, VCC is a DC power source.
そして、上記従来のセンサーは、被検出コイル1に、
バイアス電流が重畳されて被検出電流I1が流れると、
検出コイル3a,3bが逆巻きにしてあることから、該検出
コイル3a,3bには互いに逆向きの正負の検出信号が誘起
され、又該検出コイル3a,3bの共通端子が第1図に示す
如くバイパスコンデンサーC1により交流的に接地さ
れ、検出信号P1,P2として比較器IC1の(−)端子及び
(+)端子にそれぞれ入力される。一方、検出コイル3
a,3bから比較器IC1に至るライン中にノイズが誘起され
た場合、該ノイズは比較器IC1の(−)端子及び(+)
端子の両者に共に同相で入力されるので、比較器IC1か
らは出力信号が出力されず、ノイズによる誤動作はな
い。比較器IC1に第1図に示す検出信号P1,P2が入力さ
れると出力信号が出力され、更にバッファーアンプIC2
を介して計数装置に供与し、又は計数装置の他に非検出
信号I1に基づき機械装置の動作を制御するための制御
装置に出力信号を供与するものである。And, the above-mentioned conventional sensor, in the detected coil 1,
When the bias current is superimposed and the detected current I 1 flows,
Since the detection coils 3a and 3b are wound in reverse, positive and negative detection signals in opposite directions are induced in the detection coils 3a and 3b, and the common terminals of the detection coils 3a and 3b are as shown in FIG. It is AC-grounded by the bypass capacitor C 1 and is input to the (−) terminal and (+) terminal of the comparator IC 1 as detection signals P 1 and P 2 , respectively. Meanwhile, the detection coil 3
When noise is induced in the line from a, 3b to the comparator IC 1 , the noise is generated by the (−) terminal and (+) terminal of the comparator IC 1.
Since both terminals are input in the same phase, no output signal is output from the comparator IC 1 and there is no malfunction due to noise. When the detection signals P 1 and P 2 shown in FIG. 1 are input to the comparator IC 1 , an output signal is output, and further the buffer amplifier IC 2
To the counting device or to the control device for controlling the operation of the mechanical device based on the non-detection signal I 1 in addition to the counting device.
しかしながら、上記従来のセンサーは、被検出信号I
1の立上り変位時間が長くなると、誘起される検出信号
P1,P2の電圧レベルが小さくなるので、立上り時間が所
定値以上小さいパルス状態の被検出信号I1でなければ
検出ができない。又検出コイル3a,3bと比較器IC1との間
のライン中に混入するノイズは、同相で比較器IC1の
(−)端子と(+)端子とにそれぞれ供与されることに
なるために、該ノイズが(−)端子と(+)端子との相
互間で相殺されてノイズにより比較器IC1が誤動作をし
て出力信号が出力されるといったことはないが、被検出
コイル1若しくは被検出コイル3a,3bにノイズが混入す
ると、比較器IC1の(−)端子及び(+)端子にそれぞ
れ正負の逆相ノイズとして入力されるために誤動作をす
ることがあり、これを防止するとしても、検出コイル3
a,3bの検出信号を互いに反転する信号として比較器IC1
の(−)端子及び(+)端子に入力させる回路形式では
容易なことではない。更に、上記センサーは、検出コイ
ル3a,3bの両起電力を比較器IC1に加えるものであるか
ら、仮に比較器IC1として入力レベルに応じて出力信号
のレベルが変化するリニア形のものを用いて、被検出コ
イル1に流れる電流値を計測することはできず、利用範
囲が狭いといった問題があった。しかも、上記被検出コ
イル1に供与されるバイアス電流は、使用状態等に応じ
て相違し、又被検出信号I1の最大レベルも種々であ
り、これに伴い比較器IC1の出力信号の最大レベル等も
最適な値になるように調整する必要があるが、上記の如
く検出コイル3a,3bからそれぞれ逆位相の検出信号P1,P
2を比較器IC1に供与する形式では、各検出信号P1,P2の
相互間に関連性を持たせて調整しなければならないため
に、簡易にかつ高精度に行うことは容易なことではな
い。従って、上記センサーを組み込むべき被検出コイル
1の定格値等の条件に応じて抵抗R3〜R4の値、及び比
較器IC1の定格値を予め定めておき、その被検出コイル
1専用として使用しなければならない。上記の如く調整
機構を有していないことから、広範囲な利用が期待でき
ず、例えば検出コイル3a,3bのコア2にその都度各種被
検出コイル1を随意に巻回させて使用することはできな
い。However, the above-mentioned conventional sensor has the detected signal I
When the rising displacement time of 1 becomes long, the voltage levels of the induced detection signals P 1 and P 2 become small, so that detection is possible only with the detected signal I 1 in a pulse state in which the rising time is smaller than a predetermined value. Further, noise mixed in the line between the detection coils 3a and 3b and the comparator IC 1 is supplied to the (−) terminal and the (+) terminal of the comparator IC 1 in the same phase. , The noise is not canceled between the (−) terminal and the (+) terminal and the noise does not cause the comparator IC 1 to malfunction and output the output signal. If noise is mixed in the detection coils 3a and 3b, it may be input as positive and negative negative phase noise to the (-) terminal and (+) terminal of the comparator IC 1 , which may cause malfunction. Well, detection coil 3
Comparator IC 1 as a signal that inverts the detection signals of a and 3b.
It is not easy to use the circuit form in which the (-) terminal and the (+) terminal are input. Further, since the above-mentioned sensor applies both electromotive forces of the detection coils 3a and 3b to the comparator IC 1 , it is assumed that the comparator IC 1 is a linear type whose output signal level changes according to the input level. The current value flowing through the coil to be detected 1 cannot be measured by using this, and there is a problem that the range of use is narrow. Moreover, the bias current supplied to the coil to be detected 1 differs depending on the use condition and the like, and the maximum level of the signal to be detected I 1 also varies, so that the maximum output signal of the comparator IC 1 is increased accordingly. levels, etc. also need to be adjusted to the optimum value, the detection signal P 1 of the opposite phase respectively above as detecting coils 3a, from 3b, P
In the case where 2 is supplied to the comparator IC 1 , it is necessary to adjust the detection signals P 1 and P 2 so that they are related to each other, and therefore it is easy and easy to perform with high accuracy. is not. Therefore, the values of the resistors R 3 to R 4 and the rated value of the comparator IC 1 are determined in advance according to the conditions such as the rated value of the detected coil 1 in which the above sensor is to be incorporated, and the detected coil 1 is dedicated to the detected coil 1. Must be used. Since it does not have an adjusting mechanism as described above, it cannot be expected to be used in a wide range. For example, it is not possible to freely use various detected coils 1 around the core 2 of the detection coils 3a and 3b each time. .
そこで、本考案は上記事情に鑑み、被検出信号やバイ
アス電流の状態等条件に応じて検出信号のレベルを随意
に調整できて、又被検出信号としてのパルスの個数を計
数する場合はもとより、被検出信号のアナログレベルの
計測も可能で利用範囲が広い変流形センサーを提供する
ことを目的とする。Therefore, in view of the above circumstances, the present invention is capable of arbitrarily adjusting the level of the detection signal according to conditions such as the state of the detected signal and the bias current, and in addition to counting the number of pulses as the detected signal, It is an object of the present invention to provide a current-flow sensor that can measure an analog level of a detected signal and has a wide range of use.
本考案は、上記目的を達成すべくなされたもので、被
検出コイルにバイアス電流の重畳された被検出電流が供
与されると、被検出コイル、検出コイル及びコア相互間
の磁気透磁率μが変化をして検出コイルとトランジスタ
とによる発振回路の発振レベルが変動する。この時、温
度の変化で発振レベルが所定以上の値に上昇した時に温
度補償用ダイオードで抑制し、又上記バイアス電流や被
検出信号のレベル等条件に応じてレベル調整用可変抵抗
を調整して、後段装置での処理が容易なように発振レベ
ルを調整するようにしたものである。The present invention has been made to achieve the above-mentioned object, and when a detected current having a bias current superimposed thereon is supplied to the detected coil, the magnetic permeability μ between the detected coil, the detection coil and the core is increased. As a result, the oscillation level of the oscillation circuit including the detection coil and the transistor changes. At this time, when the oscillation level rises above a predetermined value due to temperature change, it is suppressed by the temperature compensation diode, and the level adjustment variable resistor is adjusted according to the conditions such as the bias current and the level of the detected signal. The oscillation level is adjusted so that the processing in the subsequent device is easy.
以下に、本考案に係る変流形センサーの一実施例を図
面に基づき説明する。An embodiment of the current-changing sensor according to the present invention will be described below with reference to the drawings.
第1図において、11はバイアス電流に重畳させて被検
出電流が供与される被検出コイルである。該被検出コイ
ル11はコア12に被検コイル13a,13bと共に巻回されてい
る。検出コイル13a,13bは、コンデンサC11、及びトラ
ンジスタQ1と共にハートレー形発振回路を形成してい
る。該トランジスタQ1のベースと検出コイル13a,13bと
の間には温度保償用ダイオードD1を挿入し、又トラン
ジスタQ1のエミッタと検出コイル13a,13bとの間には抵
抗R13及び発振レベル調整用可変抵抗VR1を挿入する。
トランジスタQ1のコレクタには、抵抗R12とコンデン
サC12とから成るミラー積分回路を経て比較器IC11の
(−)端子に接続する。比較器IC11の(+)端子には電
源+Vとアースとの間に接続された抵抗R14,R15の分圧
による基準電圧を供与するようになっている。比較器IC
11の出力端子には抵抗R18を介してバッファーアンプIC
12を接続すると共に、電源+DCとの間に電流制限用抵抗
R17と検知動作用発光ダイオードD2を挿入する。上記
バッファーアンプIC12からは計数器等の装置に出力信号
を供与するようになっている。尚、第1図において
R11,R16,R18は抵抗、C13はノイズ除去用コンデンサ、
C14は平滑用コンデンサである。In FIG. 1, reference numeral 11 is a detected coil to which a detected current is supplied by being superposed on a bias current. The detected coil 11 is wound around a core 12 together with the detected coils 13a and 13b. The detection coils 13a and 13b form a Hartley oscillator circuit together with the capacitor C 11 and the transistor Q 1 . Based detection coil 13a of the transistor Q 1, and insert the temperature coercive償用diode D 1 is between 13b, also the emitter and the detection coil 13a of the transistor Q 1, resistors R 13 and oscillation between the 13b Insert level adjustment variable resistor VR 1 .
The collector of the transistor Q 1 is connected to the (−) terminal of the comparator IC 11 via a Miller integrating circuit including a resistor R 12 and a capacitor C 12 . A reference voltage is supplied to the (+) terminal of the comparator IC 11 by dividing the resistors R 14 and R 15 connected between the power source + V and the ground. Comparator IC
A buffer amplifier IC is connected to the output terminal of 11 through a resistor R 18.
12 is connected, and a current limiting resistor R 17 and a detection operation light emitting diode D 2 are inserted between the power source and DC. The buffer amplifier IC 12 supplies an output signal to a device such as a counter. In FIG. 1, R 11 , R 16 and R 18 are resistors, C 13 is a noise removing capacitor,
C 14 is a smoothing capacitor.
次に、上記構成の変流形センサーの動作について説明
すれば、被検出コイル11に、バイアス電流と重畳されて
被検出信号I2が流れると、その被検出信号I2のレベル
に応じて被検出コイル11、コア12、及び検出コイル13a,
13bの相互間の磁気透磁率μが変化する。上記バイアス
電流は通常交流を用いるが直流であってもよい。上記磁
気透磁率μが変化すると、検出コイル13a,13b、コンデ
ンサC11及びトランジスタQ1から成るハートレー形発
振回路の発振定数が変化をして、上記被検出信号I2の
レベルに応じて発振レベルが低下する。このため、トラ
ンジスタQ1のコレクタ電圧が発振レベルの減少した分
だけ上昇して、第1図に示す検出信号P3が得られる。
該検出信号P3は抵抗R12とコンデンサC12とのミラー
積分回路で直流電圧の検出信号に変換された後に、比較
器IC11(−)端子に入力される。比較器IC11では検出信
号の入力に伴い被検出信号I2の入力に応動した個数の
計数信号としてバッファーアンプIC12を介して計数器等
に出力する。比較器IC11からの出力信号の出力時には、
該比較器IC11の出力端子がローレベルになって、直流電
源+DCから抵抗R19,R17を介して発光ダイオードD2が
通電されて点灯し、これにより検出中であることを表示
する。該計数器等ではバッファーアンプIC2からの出力
数を計数し、更にはその計数値に基づいて制御対象であ
る機械や装置の動作を制御する。上記被検出コイル11に
は、被検出パルスI2が供与されていない状態であって
も常時一定値のバイアス電流(特に交流の場合)が流れ
ていて、これに伴い被検出コイル11、コア12及び検出コ
イル13a,13b相互間の磁気透磁率μが一定値を示し、こ
れに伴いハートレー形発振回路も一定の発振周波数及び
発振レベルで発振動作をしている。従って、被検出コイ
ル11に供与されるバイアス電流の値の如何によって発振
レベル、延いてはトランジスタQ1のコレクタ電圧の値
が変わり、このコレクタ電圧の値が予め所望する値に設
定できるように発振レベル調整用可変抵抗VR1で調整す
る。被検出コイル11に供与される被検出信号I2のレベ
ルに対するトランジスタQ1のコレクタ電圧の値が最適
値になるように調整する場合も、発振レベル調整用可変
抵抗VR1で行う。このため、ミラー積分回路以降の後段
の回路装置にあっては、上記の如く発振レベル調整用可
変抵抗VR1を調整することで、被検出コイル11に供与さ
れるバイアス電流や被検出信号I2の値等の条件が相違
するものであっても、そのまま共用できる。温度補償用
ダイオードD1は温度変化によるハートレー形発振回路
の発振定数が変化した場合、温度変化によるダイオード
特性の変化で補償して常時一定の発振条件が得られるよ
うな機能を有する。ノイズはコンデンサC13で除去が可
能である。Next, the operation of the current-changing sensor having the above structure will be described. When the detected signal I 2 flows through the detected coil 11 while being superposed on the bias current, the detected signal I 2 is detected according to the level of the detected signal I 2. Detection coil 11, core 12, and detection coil 13a,
The magnetic permeability μ between 13b changes. The bias current is normally alternating current, but may be direct current. When the magnetic permeability μ changes, the oscillation constant of the Hartley oscillator circuit including the detection coils 13a and 13b, the capacitor C 11 and the transistor Q 1 changes, and the oscillation level changes according to the level of the detected signal I 2. Is reduced. Therefore, the collector voltage of the transistor Q 1 rises by the decrease in the oscillation level, and the detection signal P 3 shown in FIG. 1 is obtained.
The detection signal P 3 is converted into a DC voltage detection signal by a Miller integrating circuit including a resistor R 12 and a capacitor C 12, and then input to the comparator IC 11 (−) terminal. The comparator IC 11 outputs the count signal corresponding to the input of the detected signal I 2 in response to the input of the detection signal to the counter or the like via the buffer amplifier IC 12 . When outputting the output signal from the comparator IC 11 ,
The output terminal of the comparator IC 11 becomes low level, and the light emitting diode D 2 is energized and turned on from the DC power source + DC through the resistors R 19 and R 17 , thereby indicating that detection is in progress. The counter or the like counts the number of outputs from the buffer amplifier IC 2 , and further controls the operation of the machine or device to be controlled based on the counted value. A bias current of a constant value (especially in the case of alternating current) always flows through the detected coil 11 even when the detected pulse I 2 is not supplied, and accordingly, the detected coil 11 and the core 12 Also, the magnetic permeability μ between the detection coils 13a and 13b shows a constant value, and accordingly, the Hartley oscillator circuit also oscillates at a constant oscillation frequency and oscillation level. Therefore, the oscillation level, and consequently the value of the collector voltage of the transistor Q 1 , changes depending on the value of the bias current supplied to the detected coil 11, and the value of this collector voltage oscillates so that it can be set to a desired value in advance. Adjust with the level adjustment variable resistor VR 1 . When adjusting the collector voltage value of the transistor Q 1 to the optimum value with respect to the level of the detected signal I 2 supplied to the detected coil 11, the oscillation level adjusting variable resistor VR 1 is also used. Therefore, in the circuit device in the subsequent stage after the Miller integrating circuit, the bias current supplied to the detected coil 11 and the detected signal I 2 are adjusted by adjusting the oscillation level adjusting variable resistor VR 1 as described above. Even if the conditions such as the value of are different, they can be shared as they are. When the oscillation constant of the Hartley oscillator circuit changes due to a temperature change, the temperature compensating diode D 1 has a function of compensating for a change in diode characteristic due to a temperature change so that a constant oscillation condition can always be obtained. Noise can be removed by the capacitor C 13 .
又、上記被検出コイル11にレベルが変化するアナログ
信号を被検出信号として加えた場合には、このアナログ
信号のレベル値に応じて被検出コイル11、コア12及び検
出コイル13a,13b相互間の磁気透磁率μが変化して、ハ
ートレー形発振回路の発振レベルも変化する。このため
トランジスタQ1のコレクタ電圧は、アナログ信号のレ
ベル値に応じて値が変動することから、リニアアンプ等
を介して計測器に供与すれば、被検出コイル11に供与さ
れるアナログ信号のレベルを計測できる。When an analog signal whose level changes is added to the detected coil 11 as a detected signal, the detected coil 11, the core 12, and the detection coils 13a, 13b are connected to each other in accordance with the level value of the analog signal. As the magnetic permeability μ changes, the oscillation level of the Hartley oscillator circuit also changes. Therefore, the collector voltage of the transistor Q 1 varies depending on the level value of the analog signal. Therefore, if the collector voltage of the transistor Q 1 is supplied to the measuring instrument via a linear amplifier or the like, the level of the analog signal supplied to the detected coil 11 is increased. Can be measured.
以上の如く、本考案に係る変流形センサーによれば、
立上リ変位時間が長い被検出信号であっても良好に検出
でき、しかも被検出信号やバイアス電流の状態等の条件
に応じて検出信号のレベル、つまり発振回路の発振レベ
ルを随意に調整でき、又被検出信号としてのパルスの個
数を計数する場合はもとより、被検出信号のアナログレ
ベルの計測も可能で利用範囲が広く使用上頗る便利であ
る。As described above, according to the current sensor of the present invention,
Even a detected signal with a long startup displacement time can be satisfactorily detected, and the level of the detected signal, that is, the oscillation level of the oscillation circuit, can be adjusted arbitrarily according to conditions such as the detected signal and the state of bias current. Moreover, not only when counting the number of pulses as the detected signal, but also the analog level of the detected signal can be measured, which is convenient and has a wide range of use.
第1図は本考案に係る変流形センサーの回路図、第2図
は従来の変流形センサーの回路図である。 11……被検出コイル、12……コア、13a,13b……コイ
ル、C11……コンデンサ、Q1……トランジスタ、D1…
…温度補償用ダイオード、VR1……発振レベル調整用可
変抵抗FIG. 1 is a circuit diagram of a current-changing sensor according to the present invention, and FIG. 2 is a circuit diagram of a conventional current-changing sensor. 11 ...... be detected coil, 12 ...... core, 13a, 13b ...... coil, C 11 ...... capacitor, Q 1 ...... transistor, D 1 ...
… Temperature compensation diode, VR 1 … Variable resistor for adjusting oscillation level
Claims (1)
せて検出されるべき電流が供与される被検出コイルに磁
気的結合させた検出コイルを有し、該検出コイルと共に
発振回路を形成するトランジスタのバイアス回路に発振
レベル調整用可変抵抗を挿入し、かつ上記発振回路には
温度補償用ダイオードを挿入したことを特徴とする変流
形センサー。1. A transistor having a detection coil magnetically coupled to a bias current and a coil to be detected to which a current to be detected by being superposed on the bias current is magnetically coupled, the transistor forming an oscillation circuit together with the detection coil. A current-changing type sensor characterized in that a variable resistance for oscillation level adjustment is inserted in a bias circuit, and a temperature compensating diode is inserted in the oscillation circuit.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14289189U JPH0810799Y2 (en) | 1989-12-11 | 1989-12-11 | Current sensor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14289189U JPH0810799Y2 (en) | 1989-12-11 | 1989-12-11 | Current sensor |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0381566U JPH0381566U (en) | 1991-08-20 |
JPH0810799Y2 true JPH0810799Y2 (en) | 1996-03-29 |
Family
ID=31689698
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP14289189U Expired - Lifetime JPH0810799Y2 (en) | 1989-12-11 | 1989-12-11 | Current sensor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0810799Y2 (en) |
-
1989
- 1989-12-11 JP JP14289189U patent/JPH0810799Y2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH0381566U (en) | 1991-08-20 |
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